77 FR 20295 - United States Navy Restricted Area, Menominee River, Marinette Marine Corporation Shipyard...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-04

... to the point of origin. The restricted area will be marked by a lighted and signed floating buoy line... a signed floating buoy line without permission from the Supervisor of Shipbuilding, Conversion and...

Fatigue analysis of assembled marine floating platform for special purposes under complex water environments

NASA Astrophysics Data System (ADS)

Ma, Guang-ying; Yao, Yun-long

2018-03-01

In this paper, the fatigue lives of a new type of assembled marine floating platform for special purposes were studied. Firstly, by using ANSYS AQWA software, the hydrodynamic model of the platform was established. Secondly, the structural stresses under alternating change loads were calculated under complex water environments, such as wind, wave, current and ice. The minimum fatigue lives were obtained under different working conditions. The analysis results showed that the fatigue life of the platform structure can meet the requirements

On the classification of mixed floating pollutants on the Yellow Sea of China by using a quad-polarized SAR image

NASA Astrophysics Data System (ADS)

Wang, Xiaochen; Shao, Yun; Tian, Wei; Li, Kun

2018-06-01

This study explored different methodologies using a C-band RADARSAT-2 quad-polarized Synthetic Aperture Radar (SAR) image located over China's Yellow Sea to investigate polarization decomposition parameters for identifying mixed floating pollutants from a complex ocean background. It was found that solitary polarization decomposition did not meet the demand for detecting and classifying multiple floating pollutants, even after applying a polarized SAR image. Furthermore, considering that Yamaguchi decomposition is sensitive to vegetation and the algal variety Enteromorpha prolifera, while H/A/alpha decomposition is sensitive to oil spills, a combination of parameters which was deduced from these two decompositions was proposed for marine environmental monitoring of mixed floating sea surface pollutants. A combination of volume scattering, surface scattering, and scattering entropy was the best indicator for classifying mixed floating pollutants from a complex ocean background. The Kappa coefficients for Enteromorpha prolifera and oil spills were 0.7514 and 0.8470, respectively, evidence that the composite polarized parameters based on quad-polarized SAR imagery proposed in this research is an effective monitoring method for complex marine pollution.

Selection of preservatives for marine structural timbers in herring spawning areas.

DOT National Transportation Integrated Search

2012-12-01

Alaska marine harbors use wood for many structures that come in contact with saltwater, including piles, floats, and docks, because it is economical to buy and maintain. : However, wood immersed in saltwater is prone to attack by marine borers, vario...

Marine debris ingestion and Thayer's law - The importance of plastic color.

PubMed

Santos, Robson G; Andrades, Ryan; Fardim, Lorena M; Martins, Agnaldo Silva

2016-07-01

In recent years marine plastic pollution has gained considerable attention as a significant threat to marine animals. Despite the abundant literature related to marine debris ingestion, only a few studies attempted to understand the factors involved in debris ingestion. Plastic ingestion is commonly attributed to visual similarities of plastic fragments to animal's prey items, such as plastic bags and jellyfish. However, this simple explanation is not always coherent with the variety of debris items ingested and with the species' main prey items. We assess differences in the conspicuousness of plastic debris related to their color using Thayer's law to infer the likelihood that visual foragers detect plastic fragments. We hypothesize that marine animals that perceive floating plastic from below should preferentially ingest dark plastic fragments, whereas animals that perceive floating plastic from above should select for paler plastic fragments. Copyright © 2016 Elsevier Ltd. All rights reserved.

Floating Marine Debris in waters of the Mexican Central Pacific.

PubMed

Díaz-Torres, Evelyn R; Ortega-Ortiz, Christian D; Silva-Iñiguez, Lidia; Nene-Preciado, Alejandro; Orozco, Ernesto Torres

2017-02-15

The presence of marine debris has been reported recently in several oceans basins; there is very little information available for Mexican Pacific coasts, however. This research examined the composition, possible sources, distribution, and density of Floating Marine Debris (FMD) during nine research surveys conducted during 2010-2012 in the Mexican Central Pacific (MCP). Of 1820 floating objects recorded, 80% were plastic items. Sources of FMD were determined using key objects, which indicated that the most were related to the presence of the industrial harbor and of a growing fishing industry in the study area. Densities were relatively high, ranging from 40 to 2440objects/km 2 ; the highest densities were recorded in autumn. FMD were distributed near coastal regions, mainly in Jalisco, influenced by river outflow and surface currents. Our results seem to follow worldwide trends and highlight the need for further studies on potential ecological impacts within coastal waters of the MCP. Copyright © 2016 Elsevier Ltd. All rights reserved.

Irregular-regular mode oscillations inside plasma bubble and its fractal analysis in glow discharge magnetized plasma

NASA Astrophysics Data System (ADS)

Megalingam, Mariammal; Hari Prakash, N.; Solomon, Infant; Sarma, Arun; Sarma, Bornali

2017-04-01

Experimental evidence of different kinds of oscillations in floating potential fluctuations of glow discharge magnetized plasma is being reported. A spherical gridded cage is inserted into the ambient plasma volume for creating plasma bubbles. Plasma is produced between a spherical mesh grid and chamber. The spherical mesh grid of 80% optical transparency is connected to the positive terminal of power supply and considered as anode. Two Langmuir probes are kept in the ambient plasma to measure the floating potential fluctuations in different positions within the system, viz., inside and outside the spherical mesh grid. At certain conditions of discharge voltage (Vd) and magnetic field, irregular to regular mode appears, and it shows chronological changes with respect to magnetic field. Further various nonlinear analyses such as Recurrence Plot, Hurst exponent, and Lyapunov exponent have been carried out to investigate the dynamics of oscillation at a range of discharge voltages and external magnetic fields. Determinism, entropy, and Lmax are important measures of Recurrence Quantification Analysis which indicate an irregular to regular transition in the dynamics of the fluctuations. Furthermore, behavior of the plasma oscillation is characterized by the technique called multifractal detrended fluctuation analysis to explore the nature of the fluctuations. It reveals that it has a multifractal nature and behaves as a long range correlated process.

33 CFR 143.120 - Floating OCS facilities.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) OUTER CONTINENTAL SHELF ACTIVITIES DESIGN AND EQUIPMENT OCS Facilities § 143.120 Floating OCS facilities... (Marine Engineering) and J (Electrical Engineering) of 46 CFR chapter I and 46 CFR part 108 (Design and Equipment). Where unusual design or equipment needs make compliance impracticable, alternative proposals...

Photobleaching Kinetics of Chromophoric Dissolved Organic Matter Derived from Mangrove Leaf Litter and Floating Sargassum Colonies

EPA Science Inventory

We examined the photoreactivity of chromophoric dissolved organic matter (CDOM) derived from Rhizophora mangle (red mangrove) leaf litter and floating Sargassum colonies as these marine plants can be important contributors to coastal and open ocean CDOM pools, respectively. Mangr...

33 CFR 159.125 - Visible floating solids: Type I devices.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Visible floating solids: Type I devices. 159.125 Section 159.125 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.125...

Profile measurements in the plasma edge of mega amp spherical tokamak using a ball pen probe

NASA Astrophysics Data System (ADS)

Walkden, N. R.; Adamek, J.; Allan, S.; Dudson, B. D.; Elmore, S.; Fishpool, G.; Harrison, J.; Kirk, A.; Komm, M.

2015-02-01

The ball pen probe (BPP) technique is used successfully to make profile measurements of plasma potential, electron temperature, and radial electric field on the Mega Amp Spherical Tokamak. The potential profile measured by the BPP is shown to significantly differ from the floating potential both in polarity and profile shape. By combining the BPP potential and the floating potential, the electron temperature can be measured, which is compared with the Thomson scattering (TS) diagnostic. Excellent agreement between the two diagnostics is obtained when secondary electron emission is accounted for in the floating potential. From the BPP profile, an estimate of the radial electric field is extracted which is shown to be of the order ˜1 kV/m and increases with plasma current. Corrections to the BPP measurement, constrained by the TS comparison, introduce uncertainty into the ER measurements. The uncertainty is most significant in the electric field well inside the separatrix. The electric field is used to estimate toroidal and poloidal rotation velocities from E × B motion. This paper further demonstrates the ability of the ball pen probe to make valuable and important measurements in the boundary plasma of a tokamak.

Formulation and statistical optimization of gastric floating alginate/oil/chitosan capsules loading procyanidins: in vitro and in vivo evaluations.

PubMed

Chen, Rencai; Guo, Xiaomin; Liu, Xuecong; Cui, Haiming; Wang, Rui; Han, Jing

2018-03-01

The aim of the present work was to develop gastric floating capsules containing oil-entrapped beads loading procyanidins. The floating beads were prepared by ionotropic gelation method using sodium alginate, CaCl 2 and chitosan. The effect of three independent parameters (concentration of sodium alginate, CaCl 2 and chitosan) on entrapment efficiency were analyzed by Box-Behnken design. The floating beads were evaluated for surface morphology, particle size, density, entrapment efficiency, buoyancy, release behavior in vitro and floating ability in vivo. The prepared beads were grossly spherical in shape and the mean size was approximately 1.54±0.17mm. The density was 0.97g/cm 3 . And the optimal conditions were as follows: concentration of sodium alginate, CaCl 2 and chitosan were 33.75mg/mL, 9.84mg/mL and 9.05mg/mL, respectively. The optimized formulation showed entrapment efficiency of 88.84±1.04% within small error-value (0.65). The release mechanism of floating capsules followed Korsmeyer-Peppas model (r 2 =0.9902) with non-Fickian release. The gastric floating capsules exhibited 100% floating percentage in vitro and they could float on the top of gastric juice for 5h in vivo. Therefore, the floating capsules are able to prolong the gastroretentive delivery of procyanidins. Copyright © 2017 Elsevier B.V. All rights reserved.

78 FR 48180 - Consolidation of Officer in Charge, Marine Inspection For Outer Continental Shelf Activities...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-07

... for all Mobile Offshore Drilling Units and Floating Outer Continental Shelf Facilities (as defined in... Commander. Vessels requiring Coast Guard inspection include Mobile Offshore Drilling Units (MODUs), Floating... engage directly in oil and gas exploration or production in the offshore waters of the Eighth Coast Guard...

Marine ice sheet model performance depends on basal sliding physics and sub-shelf melting

NASA Astrophysics Data System (ADS)

Gladstone, Rupert Michael; Warner, Roland Charles; Galton-Fenzi, Benjamin Keith; Gagliardini, Olivier; Zwinger, Thomas; Greve, Ralf

2017-01-01

Computer models are necessary for understanding and predicting marine ice sheet behaviour. However, there is uncertainty over implementation of physical processes at the ice base, both for grounded and floating glacial ice. Here we implement several sliding relations in a marine ice sheet flow-line model accounting for all stress components and demonstrate that model resolution requirements are strongly dependent on both the choice of basal sliding relation and the spatial distribution of ice shelf basal melting.Sliding relations that reduce the magnitude of the step change in basal drag from grounded ice to floating ice (where basal drag is set to zero) show reduced dependence on resolution compared to a commonly used relation, in which basal drag is purely a power law function of basal ice velocity. Sliding relations in which basal drag goes smoothly to zero as the grounding line is approached from inland (due to a physically motivated incorporation of effective pressure at the bed) provide further reduction in resolution dependence.A similar issue is found with the imposition of basal melt under the floating part of the ice shelf: melt parameterisations that reduce the abruptness of change in basal melting from grounded ice (where basal melt is set to zero) to floating ice provide improved convergence with resolution compared to parameterisations in which high melt occurs adjacent to the grounding line.Thus physical processes, such as sub-glacial outflow (which could cause high melt near the grounding line), impact on capability to simulate marine ice sheets. If there exists an abrupt change across the grounding line in either basal drag or basal melting, then high resolution will be required to solve the problem. However, the plausible combination of a physical dependency of basal drag on effective pressure, and the possibility of low ice shelf basal melt rates next to the grounding line, may mean that some marine ice sheet systems can be reliably simulated at a coarser resolution than currently thought necessary.

Investigating Passively Floating and Weakly Swimming Organisms: An Activity for Beginning Marine Education Students.

ERIC Educational Resources Information Center

Schlenker, Richard M.

This document presents the outline of a marine biology science unit designed to introduce students to the study and collection of plankton. Extensive details on plankton collections and a seven-item quiz are included. (SL)

Seabirds, gyres and global trends in plastic pollution.

PubMed

van Franeker, Jan A; Law, Kara Lavender

2015-08-01

Fulmars are effective biological indicators of the abundance of floating plastic marine debris. Long-term data reveal high plastic abundance in the southern North Sea, gradually decreasing to the north at increasing distance from population centres, with lowest levels in high-arctic waters. Since the 1980s, pre-production plastic pellets in North Sea fulmars have decreased by ∼75%, while user plastics varied without a strong overall change. Similar trends were found in net-collected floating plastic debris in the North Atlantic subtropical gyre, with a ∼75% decrease in plastic pellets and no obvious trend in user plastic. The decreases in pellets suggest that changes in litter input are rapidly visible in the environment not only close to presumed sources, but also far from land. Floating plastic debris is rapidly "lost" from the ocean surface to other as-yet undetermined sinks in the marine environment. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Floating potential in electronegative plasmas for non-zero ion temperatures

NASA Astrophysics Data System (ADS)

Regodón, Guillermo Fernando; Fernández Palop, José Ignacio; Tejero-del-Caz, Antonio; Díaz-Cabrera, Juan Manuel; Carmona-Cabezas, Rafael; Ballesteros, Jerónimo

2018-02-01

The floating potential of a Langmuir probe immersed in an electronegative plasma is studied theoretically under the assumption of radial positive ion fluid movement for non-zero positive ion temperature: both cylindrical and spherical geometries are studied. The model is solvable exactly. The special characteristics of the electronegative pre-sheath are found and the influence of the stratified electronegative pre-sheath is shown to be very small in practical applications. It is suggested that the use of the floating potential in the measurement of negative ions population density is convenient, in view of the numerical results obtained. The differences between the two radial geometries, which become very important for small probe radii of the order of magnitude of the Debye length, are studied.

Profile measurements in the plasma edge of mega amp spherical tokamak using a ball pen probe

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

Walkden, N. R., E-mail: nrw504@york.ac.uk; Department of Physics, York Plasma Institute, University of York, Heslington, York YO10 5DD; Adamek, J.

The ball pen probe (BPP) technique is used successfully to make profile measurements of plasma potential, electron temperature, and radial electric field on the Mega Amp Spherical Tokamak. The potential profile measured by the BPP is shown to significantly differ from the floating potential both in polarity and profile shape. By combining the BPP potential and the floating potential, the electron temperature can be measured, which is compared with the Thomson scattering (TS) diagnostic. Excellent agreement between the two diagnostics is obtained when secondary electron emission is accounted for in the floating potential. From the BPP profile, an estimate ofmore » the radial electric field is extracted which is shown to be of the order ∼1 kV/m and increases with plasma current. Corrections to the BPP measurement, constrained by the TS comparison, introduce uncertainty into the E{sub R} measurements. The uncertainty is most significant in the electric field well inside the separatrix. The electric field is used to estimate toroidal and poloidal rotation velocities from E × B motion. This paper further demonstrates the ability of the ball pen probe to make valuable and important measurements in the boundary plasma of a tokamak.« less

Gastroretentive extended-release floating granules prepared using a novel fluidized hot melt granulation (FHMG) technique.

PubMed

Zhai, H; Jones, D S; McCoy, C P; Madi, A M; Tian, Y; Andrews, G P

2014-10-06

The objective of this work was to investigate the feasibility of using a novel granulation technique, namely, fluidized hot melt granulation (FHMG), to prepare gastroretentive extended-release floating granules. In this study we have utilized FHMG, a solvent free process in which granulation is achieved with the aid of low melting point materials, using Compritol 888 ATO and Gelucire 50/13 as meltable binders, in place of conventional liquid binders. The physicochemical properties, morphology, floating properties, and drug release of the manufactured granules were investigated. Granules prepared by this method were spherical in shape and showed good flowability. The floating granules exhibited sustained release exceeding 10 h. Granule buoyancy (floating time and strength) and drug release properties were significantly influenced by formulation variables such as excipient type and concentration, and the physical characteristics (particle size, hydrophilicity) of the excipients. Drug release rate was increased by increasing the concentration of hydroxypropyl cellulose (HPC) and Gelucire 50/13, or by decreasing the particle size of HPC. Floating strength was improved through the incorporation of sodium bicarbonate and citric acid. Furthermore, floating strength was influenced by the concentration of HPC within the formulation. Granules prepared in this way show good physical characteristics, floating ability, and drug release properties when placed in simulated gastric fluid. Moreover, the drug release and floating properties can be controlled by modification of the ratio or physical characteristics of the excipients used in the formulation.

76 FR 71322 - Taking and Importing Marine Mammals; U.S. Navy Training in the Hawaii Range Complex

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-17

..., most operationally sound method of initiating a demolition charge on a floating mine or mine at depth...; require building/ deploying an improvised, bulky, floating system for the receiver; and add another 180 ft... charge initiating device are taken to the detonation point. Military forms of C-4 are used as the...

Biofouling community composition across a range of environmental conditions and geographical locations suitable for floating marine renewable energy generation.

PubMed

Macleod, Adrian K; Stanley, Michele S; Day, John G; Cook, Elizabeth J

2016-01-01

Knowledge of biofouling typical of marine structures is essential for engineers to define appropriate loading criteria in addition to informing other stakeholders about the ecological implications of creating novel artificial environments. There is a lack of information regarding biofouling community composition (including weight and density characteristics) on floating structures associated with future marine renewable energy generation technologies. A network of navigation buoys were identified across a range of geographical areas, environmental conditions (tidal flow speed, temperature and salinity), and deployment durations suitable for future developments. Despite the perceived importance of environmental and temporal factors, geographical location explained the greatest proportion of the observed variation in community composition, emphasising the importance of considering geography when assessing the impact of biofouling on device functioning and associated ecology. The principal taxa associated with variation in biofouling community composition were mussels (Mytilus edulis), which were also important when determining loading criteria.

Marine floating microbial fuel cell involving aerobic biofilm on stainless steel cathodes.

PubMed

Erable, B; Lacroix, R; Etcheverry, L; Féron, D; Delia, M L; Bergel, A

2013-08-01

Here is presented a new design of a floating marine MFC in which the inter-electrode space is constant. This design allows the generation of stable current for applications in environments where the water column is large or subject to fluctuations such as tidal effects. The operation of the first prototype was validated by running a continuous test campaign for 6months. Performance in terms of electricity generation was already equivalent to what is conventionally reported in the literature with basic benthic MFCs despite the identification of a large internal resistance in the proposed design of the floating system. This high internal resistance is mainly explained by poor positioning of the membrane separating the anode compartment from the open seawater. The future objectives are to achieve more consistent performance and a second-generation prototype is now being developed, mainly incorporating a modification of the separator position and a stainless steel biocathode with a large bioavailable surface. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of polarization forces on carbon deposition on a non-spherical nanoparticle. Monte Carlo simulations [Effect of polarization forces on atom deposition on a non-spherical nanoparticle. Monte Carlo simulations

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

Nemchinsky, V.; Khrabry, A.

Trajectories of a polarizable species (atoms or molecules) in the vicinity of a negatively charged nanoparticle (at a floating potential) are considered. The atoms are pulled into regions of strong electric field by polarization forces. The polarization increases the deposition rate of the atoms and molecules at the nanoparticle. The effect of the non-spherical shape of the nanoparticle is investigated by the Monte Carlo method. The shape of the non-spherical nanoparticle is approximated by an ellipsoid. The total deposition rate and its flux density distribution along the nanoparticle surface are calculated. As a result, it is shown that the fluxmore » density is not uniform along the surface. It is maximal at the nanoparticle tips.« less

Effect of polarization forces on carbon deposition on a non-spherical nanoparticle. Monte Carlo simulations [Effect of polarization forces on atom deposition on a non-spherical nanoparticle. Monte Carlo simulations

DOE PAGES

Nemchinsky, V.; Khrabry, A.

2018-02-01

Trajectories of a polarizable species (atoms or molecules) in the vicinity of a negatively charged nanoparticle (at a floating potential) are considered. The atoms are pulled into regions of strong electric field by polarization forces. The polarization increases the deposition rate of the atoms and molecules at the nanoparticle. The effect of the non-spherical shape of the nanoparticle is investigated by the Monte Carlo method. The shape of the non-spherical nanoparticle is approximated by an ellipsoid. The total deposition rate and its flux density distribution along the nanoparticle surface are calculated. As a result, it is shown that the fluxmore » density is not uniform along the surface. It is maximal at the nanoparticle tips.« less

Floating Ocean Platform

DTIC Science & Technology

2003-08-15

floating structures create novel habitats for subtidal epibiota?, MARINE ECOLOGY -PROGRESS SERIES, 43-52 Mar. Ecol.- Prog. Ser., 2002 Vegueria, SFJ Godoy... ECOLOGICAL APPLICATIONS, 350-366 Ecol. Appl., 2000 Niedzwecki, JM van de Lindt, JW Gage, JH Teigen, PS, Design estimates of surface wave interaction with...The ecological effects beyond the offshore platform, Coastal Zone: Proceedings of the Symposium on Coastal and Ocean Management, v 2, n pt2, 1989, p

Balls and Spheres

ERIC Educational Resources Information Center

Szekely, George

2011-01-01

This article describes an art lesson that allows students to set up and collect sphere canvases. Spheres move art away from a rectangular canvas into a dimension that requires new planning and painting. From balls to many other spherical canvases that bounce, roll, float and fly, art experiences are envisioned by students. Even if adults recognize…

The Arctic Ocean as a dead end for floating plastics in the North Atlantic branch of the Thermohaline Circulation

PubMed Central

Cózar, Andrés; Martí, Elisa; Duarte, Carlos M.; García-de-Lomas, Juan; van Sebille, Erik; Ballatore, Thomas J.; Eguíluz, Victor M.; González-Gordillo, J. Ignacio; Pedrotti, Maria L.; Echevarría, Fidel; Troublè, Romain; Irigoien, Xabier

2017-01-01

The subtropical ocean gyres are recognized as great marine accummulation zones of floating plastic debris; however, the possibility of plastic accumulation at polar latitudes has been overlooked because of the lack of nearby pollution sources. In the present study, the Arctic Ocean was extensively sampled for floating plastic debris from the Tara Oceans circumpolar expedition. Although plastic debris was scarce or absent in most of the Arctic waters, it reached high concentrations (hundreds of thousands of pieces per square kilometer) in the northernmost and easternmost areas of the Greenland and Barents seas. The fragmentation and typology of the plastic suggested an abundant presence of aged debris that originated from distant sources. This hypothesis was corroborated by the relatively high ratios of marine surface plastic to local pollution sources. Surface circulation models and field data showed that the poleward branch of the Thermohaline Circulation transfers floating debris from the North Atlantic to the Greenland and Barents seas, which would be a dead end for this plastic conveyor belt. Given the limited surface transport of the plastic that accumulated here and the mechanisms acting for the downward transport, the seafloor beneath this Arctic sector is hypothesized as an important sink of plastic debris. PMID:28439534

The Arctic Ocean as a dead end for floating plastics in the North Atlantic branch of the Thermohaline Circulation.

PubMed

Cózar, Andrés; Martí, Elisa; Duarte, Carlos M; García-de-Lomas, Juan; van Sebille, Erik; Ballatore, Thomas J; Eguíluz, Victor M; González-Gordillo, J Ignacio; Pedrotti, Maria L; Echevarría, Fidel; Troublè, Romain; Irigoien, Xabier

2017-04-01

The subtropical ocean gyres are recognized as great marine accummulation zones of floating plastic debris; however, the possibility of plastic accumulation at polar latitudes has been overlooked because of the lack of nearby pollution sources. In the present study, the Arctic Ocean was extensively sampled for floating plastic debris from the Tara Oceans circumpolar expedition. Although plastic debris was scarce or absent in most of the Arctic waters, it reached high concentrations (hundreds of thousands of pieces per square kilometer) in the northernmost and easternmost areas of the Greenland and Barents seas. The fragmentation and typology of the plastic suggested an abundant presence of aged debris that originated from distant sources. This hypothesis was corroborated by the relatively high ratios of marine surface plastic to local pollution sources. Surface circulation models and field data showed that the poleward branch of the Thermohaline Circulation transfers floating debris from the North Atlantic to the Greenland and Barents seas, which would be a dead end for this plastic conveyor belt. Given the limited surface transport of the plastic that accumulated here and the mechanisms acting for the downward transport, the seafloor beneath this Arctic sector is hypothesized as an important sink of plastic debris.

1:50 Scale Testing of Three Floating Wind Turbines at MARIN and Numerical Model Validation Against Test Data

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

Dagher, Habib; Viselli, Anthony; Goupee, Andrew

The primary goal of the basin model test program discussed herein is to properly scale and accurately capture physical data of the rigid body motions, accelerations and loads for different floating wind turbine platform technologies. The intended use for this data is for performing comparisons with predictions from various aero-hydro-servo-elastic floating wind turbine simulators for calibration and validation. Of particular interest is validating the floating offshore wind turbine simulation capabilities of NREL’s FAST open-source simulation tool. Once the validation process is complete, coupled simulators such as FAST can be used with a much greater degree of confidence in design processesmore » for commercial development of floating offshore wind turbines. The test program subsequently described in this report was performed at MARIN (Maritime Research Institute Netherlands) in Wageningen, the Netherlands. The models considered consisted of the horizontal axis, NREL 5 MW Reference Wind Turbine (Jonkman et al., 2009) with a flexible tower affixed atop three distinct platforms: a tension leg platform (TLP), a spar-buoy modeled after the OC3 Hywind (Jonkman, 2010) and a semi-submersible. The three generic platform designs were intended to cover the spectrum of currently investigated concepts, each based on proven floating offshore structure technology. The models were tested under Froude scale wind and wave loads. The high-quality wind environments, unique to these tests, were realized in the offshore basin via a novel wind machine which exhibits negligible swirl and low turbulence intensity in the flow field. Recorded data from the floating wind turbine models included rotor torque and position, tower top and base forces and moments, mooring line tensions, six-axis platform motions and accelerations at key locations on the nacelle, tower, and platform. A large number of tests were performed ranging from simple free-decay tests to complex operating conditions with irregular sea states and dynamic winds.« less

Selection and optimization of mooring cables on floating platform for special purposes

NASA Astrophysics Data System (ADS)

Ma, Guang-ying; Yao, Yun-long; Zhao, Chen-yao

2017-08-01

This paper studied a new type of assembled marine floating platform for special purposes. The selection and optimization of mooring cables on the floating platform are studied. By using ANSYS AQWA software, the hydrodynamic model of the platform was established to calculate the time history response of the platform motion under complex water environments, such as wind, wave, current and mooring. On this basis, motion response and cable tension were calculated with different cable mooring states under the designed environmental load. Finally, the best mooring scheme to meet the cable strength requirements was proposed, which can lower the motion amplitude of the platform effectively.

Effect of Gravity on the Mammalian Cell Deformation

NASA Technical Reports Server (NTRS)

Hung, R. J.; Tsao, Y.; Gonda, Steven

1995-01-01

The effect of human cell immersed in culture liquid under a micro-gravity environment has been investigated. The study is based on the numerical simulation of the configuration of human cell affected by the time dependent variation of gravity acceleration ranging from 10(exp -3) to 2 g(sub o) (g(sub o) = 9.81 m/s(exp 2)) in 15 seconds. Both the free floating cell and the cell contacted to the upper and lower inclined walls imposed by the time-dependent reduced gravity acceleration are considered in this study. The results show that the cell configuration changes from spherical to horizontally elongated ellipsoid for both the free floating cell and the cell sitting on the lower inclined wall while the cell configuration varies from spherical to vertically elongated ellipsoid for the cell hanging to the upper inclined wall when the gravity acceleration increases. Experimental observations, carried out of human cells exposed to the variation of gravity levels, show that the results of experimental observations agree exactly with the theoretical model computation described in this paper. These results sre significant for humans exposed to the micro-gravity environment.

VLF Source Localization with a Freely Drifting Sensor Array

DTIC Science & Technology

1992-09-01

Simultaneous Measurement of Infra - sonic Acoustic Particle Velocity and Acoustic Pressure in the Ocean by F-ely Drifting Swallow Floats," IEEEJ. Ocean. Eng., vol...Pacific. Marine Physical Laboratory’s set of nine freely drifting, infrasonic sensors, capable of recording ocean ambient noise in the 1- to 25-Hz range...Terms. 15. Number of Pages, Swallow float, matched-field processing, infrasonic sensor, vlf source localization 153 16. Price Code. 17. Seorlity

BIO ARGO floats: tools for operational monitoring of the Black Sea

NASA Astrophysics Data System (ADS)

Palazov, Atanas; Slabakova, Violeta; Peneva, Elisaveta; Stanev, Emil

2014-05-01

The assessment of ecological status in the context of the Water Framework Directive (WFD) and Marine Strategy Framework Directive (MSFD) requires comprehensive knowledge and understanding of the physical and biogeochemical processes that determine the functioning of marine ecosystems. One of the main challenges however is the need of data with frequency relevant to the spatial and temporal scales of the ecological processes. The majority of in situ observations that are commonly used for ecological monitoring of the Black Sea are generally based on near-shore monitoring programs or irregular oceanographic cruises that provide either non-synoptic, coarse resolution realizations of large scale processes or detailed, but time and site specific snapshots of local features. These gaps can be filled by two independent sources: satellite observation and profiling floats. In fact satellite ocean color sensors allows for determination at synoptic scale of water quality parameters through its absorption properties. However the satellite ocean color methods have a number of limitations such as: measurements can only be made during daylight hours; require cloud-free conditions and are sensitive to atmospheric aerosols; provide information only for the upper layer of the ocean (approximately the depth of 10% incident light); algorithms developed for global applications are a source of large uncertainties in the marginal seas and costal areas. These constrains of the optical remote sensing observations can be avoided by using miniature biogeochemical sensors and autonomous platforms that offer remarkable perspectives for observing the "biological" ocean, notably at critical spatiotemporal scales which have been out of reach until recently (Claustre et al., 2010). In the frame of "E-AIMS: Euro-Argo Improvements for the GMES marine Service" 7 EC FP project two Bio Argo floats were deployed in the Black Sea. Beside the traditionally CTD the floats were equipped with biogeochemical sensors (oxygen, irradiance, chl-a and backscattering). The selection of the deployment locations was limited only to the Bulgarian Black Sea waters, so that the optimal deployment strategy that has been chosen was the floats to be deployed in the maximum distant positions from each other along the Black Sea geostrophic current at depth ~ 1800 m. Coincident biogeochemical and in-water radiometric measurements were collected at the time of each float deployment to ensure intercalibration of the instruments mounted on the floats and as well as to find empirical relationship between optical data and biogeochemical variables. The data obtained form Bio floats will be used to: investigate the seasonal evolution of oxygen in the upper layers, including the subsurface oxygen maximum; study the seasonal and inter annual dynamics of phytoplankton blooms in the deeper Black Sea; cross validation of satellite derived Chl-a and backscattering. References: Claustre et al. (2010). Bio-optical profiling floats as new observational tools for biogeochemical and ecosystem studies: potential synergies with ocean color remote sensing. Proceedings of the "OceanObs'09: Sustained Ocean Observations and Information for Society" Conference, Venice/Italy.

Indicators: Phytoplankton

EPA Pesticide Factsheets

Phytoplankton are free-floating, microscopic algae that inhabit the sunlit, upper layer of most freshwater and marine environments. They are usually responsible for the color and clarity of lakes, wetlands, rivers, streams and estuaries.

33 CFR 143.120 - Floating OCS facilities.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (Marine Engineering) and J (Electrical Engineering) of 46 CFR chapter I and 46 CFR part 108 (Design and... that provide an equivalent level of safety may be accepted. These requirements do not apply to...

33 CFR 143.120 - Floating OCS facilities.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (Marine Engineering) and J (Electrical Engineering) of 46 CFR chapter I and 46 CFR part 108 (Design and... that provide an equivalent level of safety may be accepted. These requirements do not apply to...

33 CFR 143.120 - Floating OCS facilities.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (Marine Engineering) and J (Electrical Engineering) of 46 CFR chapter I and 46 CFR part 108 (Design and... that provide an equivalent level of safety may be accepted. These requirements do not apply to...

Catamaran or semi-submersible for floating platform - selection of a better design

NASA Astrophysics Data System (ADS)

Qasim, Idrees; Gao, Liangtian; Peng, Duojin; Liu, Bo

2018-02-01

With nonstop advancement in marine engineering, more and more new structures are being designed and explored for tidal current energy. There are three different kinds of support structures for tidal current power station mostly in use, which are sea-bed mounted/gravity based system, pile mounted system and floating moored platform. Comparing all of them, the floating mooring system is most suitable for deep water systems and the application of this arrangement is widely usable. In this paper, a semi-submersible and a catamaran as floating platforms for tidal current power stations are studied are compared on the basis of its economics, efficiency of turbine and stability of the station. Based on basic ship theory and using software MAXSURF, the stability of Catamaran tidal current power station is also calculated. It is found that the catamaran design is optimal choice.

Seismic monitoring in the oceans by autonomous floats.

PubMed

Sukhovich, Alexey; Bonnieux, Sébastien; Hello, Yann; Irisson, Jean-Olivier; Simons, Frederik J; Nolet, Guust

2015-08-20

Our understanding of the internal dynamics of the Earth is largely based on images of seismic velocity variations in the mantle obtained with global tomography. However, our ability to image the mantle is severely hampered by a lack of seismic data collected in marine areas. Here we report observations made under different noise conditions (in the Mediterranean Sea, the Indian and Pacific Oceans) by a submarine floating seismograph, and show that such floats are able to fill the oceanic data gap. Depending on the ambient noise level, the floats can record between 35 and 63% of distant earthquakes with a moment magnitude M≥6.5. Even magnitudes <6.0 can be successfully observed under favourable noise conditions. The serendipitous recording of an earthquake swarm near the Indian Ocean triple junction enabled us to establish a threshold magnitude between 2.7 and 3.4 for local earthquakes in the noisiest of the three environments.

Seismic monitoring in the oceans by autonomous floats

PubMed Central

Sukhovich, Alexey; Bonnieux, Sébastien; Hello, Yann; Irisson, Jean-Olivier; Simons, Frederik J.; Nolet, Guust

2015-01-01

Our understanding of the internal dynamics of the Earth is largely based on images of seismic velocity variations in the mantle obtained with global tomography. However, our ability to image the mantle is severely hampered by a lack of seismic data collected in marine areas. Here we report observations made under different noise conditions (in the Mediterranean Sea, the Indian and Pacific Oceans) by a submarine floating seismograph, and show that such floats are able to fill the oceanic data gap. Depending on the ambient noise level, the floats can record between 35 and 63% of distant earthquakes with a moment magnitude M≥6.5. Even magnitudes <6.0 can be successfully observed under favourable noise conditions. The serendipitous recording of an earthquake swarm near the Indian Ocean triple junction enabled us to establish a threshold magnitude between 2.7 and 3.4 for local earthquakes in the noisiest of the three environments. PMID:26289598

Biofouling on buoyant marine plastics: An experimental study into the effect of size on surface longevity.

PubMed

Fazey, Francesca M C; Ryan, Peter G

2016-03-01

Recent estimates suggest that roughly 100 times more plastic litter enters the sea than is found floating at the sea surface, despite the buoyancy and durability of many plastic polymers. Biofouling by marine biota is one possible mechanism responsible for this discrepancy. Microplastics (<5 mm in diameter) are more scarce than larger size classes, which makes sense because fouling is a function of surface area whereas buoyancy is a function of volume; the smaller an object, the greater its relative surface area. We tested whether plastic items with high surface area to volume ratios sank more rapidly by submerging 15 different sizes of polyethylene samples in False Bay, South Africa, for 12 weeks to determine the time required for samples to sink. All samples became sufficiently fouled to sink within the study period, but small samples lost buoyancy much faster than larger ones. There was a direct relationship between sample volume (buoyancy) and the time to attain a 50% probability of sinking, which ranged from 17 to 66 days of exposure. Our results provide the first estimates of the longevity of different sizes of plastic debris at the ocean surface. Further research is required to determine how fouling rates differ on free floating debris in different regions and in different types of marine environments. Such estimates could be used to improve model predictions of the distribution and abundance of floating plastic debris globally. Copyright © 2016 Elsevier Ltd. All rights reserved.

Borofloat and Starphire Float Glasses: A Comparison

DOE PAGES

Wereszczak, Andrew A.; Anderson Jr., Charles E.

2014-10-28

Borofloat ® borosilicate float glass and Starphire ® soda-lime silicate float glass are used in transparent protective systems. They are known to respond differently in some ballistic and triaxial loading conditions, and efforts are underway to understand the causes of those differences. Toward that, a suite of test and material characterizations were completed in the present study on both glasses so to identify what differences exist among them. Compositional, physical properties, elastic properties, flaw size distributions and concentrations, tensile/flexure strength, fracture toughness, spherical indentation and hardness, transmission electron microscopy, striae, high pressure responses via diamond anvil cell testing, laser shockmore » differences, and internal porosity were examined. Differences between these two float glasses were identified for many of these properties and characteristics, and the role of three (striae, high pressures where permanent densification can initiate, and sub-micron-sized porosity) lack understanding and deserve further attention. Lastly, the contributing roles of any of those properties or characteristics to triaxial or ballistic loading responses are not definitive; however, they provide potential correlations that may lead to improved understanding and management of loading responses in glasses used in transparent protective systems.« less

Application of ethyl cellulose, microcrystalline cellulose and octadecanol for wax based floating solid dispersion pellets.

PubMed

Yan, Hong-Xiang; Zhang, Shuang-Shuang; He, Jian-Hua; Liu, Jian-Ping

2016-09-05

The present study aimed to develop and optimize the wax based floating sustained-release dispersion pellets for a weakly acidic hydrophilic drug protocatechuic acid to achieve prolonged gastric residence time and improved bioavailability. This low-density drug delivery system consisted of octadecanol/microcrystalline cellulose mixture matrix pellet cores prepared by extrusion-spheronization technique, coated with drug/ethyl cellulose 100cp solid dispersion using single-step fluid-bed coating method. The formulation-optimized pellets could maintain excellent floating state without lag time and sustain the drug release efficiently for 12h based on non-Fickian transport mechanism. Observed by SEM, the optimized pellet was the dispersion-layered spherical structure containing a compact inner core. DSC, XRD and FTIR analysis revealed drug was uniformly dispersed in the amorphous molecule form and had no significant physicochemical interactions with the polymer dispersion carrier. The stability study of the resultant pellets further proved the rationality and integrity of the developed formulation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Data Analysis of the Floating Potential Measurement Unit aboard the International Space Station

NASA Technical Reports Server (NTRS)

Barjatya, Aroh; Swenson, Charles M.; Thompson, Donald C.; Wright, Kenneth H., Jr.

2009-01-01

We present data from the Floating Potential Measurement Unit (FPMU), that is deployed on the starboard (S1) truss of the International Space Station. The FPMU is a suite of instruments capable of redundant measurements of various plasma parameters. The instrument suite consists of: a Floating Potential Probe, a Wide-sweeping spherical Langmuir probe, a Narrow-sweeping cylindrical Langmuir Probe, and a Plasma Impedance Probe. This paper gives a brief overview of the instrumentation and the received data quality, and then presents the algorithm used to reduce I-V curves to plasma parameters. Several hours of data is presented from August 5th, 2006 and March 3rd, 2007. The FPMU derived plasma density and temperatures are compared with the International Reference Ionosphere (IRI) and USU-Global Assimilation of Ionospheric Measurement (USU-GAIM) models. Our results show that the derived in-situ density matches the USU-GAIM model better than the IRI, and the derived in-situ temperatures are comparable to the average temperatures given by the IRI.

U.S. Senate examines concerns about marine debris from 2011 Japan tsunami

NASA Astrophysics Data System (ADS)

Showstack, Randy

2012-05-01

Approximately 5 million tons of debris washed into the Pacific Ocean from Japan following the 11 March 2011 tsunami, and the Japanese government estimates that 1.5 million tons may still be floating on or below the ocean surface. However, it is not known how much debris may reach U.S. shores, an official from the National Oceanic and Atmospheric Administration (NOAA) testified at a 17 May Senate hearing. "If you've got 1.5 [million tons] that's floating and you leave it in there for a year, how much of that is still going be floating and available to come ashore? We don't have a clue," David Kennedy, NOAA assistant administrator for ocean services and coastal zone management, testified before a subcommittee of the Senate Committee on Commerce, Science, and Transportation. He said that some materials pushed by the wind could be expected to float but that materials pushed by currents under the surface are difficult to find. "A whole bunch of the 1.5 million is construction debris, and do [wooden] two-by-fours still float after a year? We're not sure."

Modelling the global distribution and risk of small floating plastic debris

NASA Astrophysics Data System (ADS)

van Sebille, E.; Wilcox, C.; Lebreton, L.; Maximenko, N. A.; Sherman, P.; Hardesty, B. D.; van Franeker, J. A.; Eriksen, M.; Siegel, D.; Galgani, F.; Lavender Law, K. L.

2016-02-01

Microplastic debris floating at the ocean surface can harm marine life. Understanding the severity of this harm requires knowledge of plastic abundance and distributions. Dozens of expeditions measuring microplastics have been carried out since the 1970s, but they have primarily focused on the North Pacific and North Atlantic accumulation zones, with much sparser coverage elsewhere. Here, we use the largest dataset of microplastic measurements collated to date to assess the confidence we can have in global estimates of microplastic abundance and mass. We use a rigorous statistical framework to standardize a global dataset of plastic marine debris measured using surface-trawling plankton nets and coupled this with three different ocean circulation models to spatially interpolate the observations. Our estimates show that the accumulated number of microplastic particles in 2014 ranges from 15 to 51 trillion particles, weighing between 93 and 236 thousand metric tons, which is only approximately 1% of global plastic waste available to enter the ocean in the year 2010. These estimates are larger than previous global estimates, but vary widely because the scarcity of data in most of the world ocean, differences in model formulations, and fundamental knowledge gaps in the sources, transformations and fates of microplastics in the ocean. We then use this global distribution of small floating plastic debris to (i) map out where in the ocean the risk to marine life (seabirds, plankton growth) is greatest and to (ii) show that mitigation of the plastic problem can most aptly be done near coastlines, particularly in Asia, rather than in the centres of the gyres.

76 FR 30309 - Marine Mammals and Endangered Species; File Nos. 14245, 1596-03, and 14726-01

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-25

..., condition, diet, and potential Mississippi Canyon 252 oil exposure of pelagic sea turtles associated with floating Sargassum as part of the post-spill Natural Resources Damage Assessment of the BP Deepwater...

Dragging a floating horizontal cylinder

NASA Astrophysics Data System (ADS)

Lee, Duck-Gyu; Kim, Ho-Young

2010-11-01

A cylinder immersed in a fluid stream experiences a drag, and it is well known that the drag coefficient is a function of the Reynolds number only. Here we study the force exerted on a long horizontal cylinder that is dragged perpendicular to its axis while floating on an air-water interface with a high Reynolds number. In addition to the flow-induced drag, the floating body is subjected to capillary forces along the contact line where the three phases of liquid/solid/gas meet. We first theoretically predict the meniscus profile around the horizontally moving cylinder assuming the potential flow, and show that the profile is in good agreement with that obtained experimentally. Then we compare our theoretical predictions and experimental measurement results for the drag coefficient of a floating horizontal cylinder that is given by a function of the Weber number and the Bond number. This study can help us to understand the horizontal motion of partially submerged objects at air-liquid interface, such as semi-aquatic insects and marine plants.

Study on design method and vibration reduction characteristic of floating raft with periodic structure

NASA Astrophysics Data System (ADS)

Fang, Yuanyuan; Zuo, Yanyan; Xia, Zhaowang

2018-03-01

The noise level is getting higher with the development of high-power marine power plant. Mechanical noise is one of the most obvious noise sources which not only affect equipment reliability, riding comfort and working environment, but also enlarge underwater noise. The periodic truss type device which is commonly applied in fields of aerospace and architectural is introduced to floating raft construction in ship. Four different raft frame structure are designed in the paper. The vibration transmissibility is taken as an evaluation index to measure vibration isolation effect. A design scheme with the best vibration isolation effect is found by numerical method. Plate type and the optimized periodic truss type raft frame structure are processed to experimental verify vibration isolation effect of the structure of the periodic raft. The experimental results demonstrate that the same quality of the periodic truss floating raft has better isolation effect than that of the plate type floating raft.

Dynamics and early post-tsunami evolution of floating marine debris near Fukushima Daiichi

NASA Astrophysics Data System (ADS)

Matthews, John Philip; Ostrovsky, Lev; Yoshikawa, Yutaka; Komori, Satoru; Tamura, Hitoshi

2017-08-01

The devastating tsunami triggered by the Tōhoku-Oki earthquake of 11 March 2011 caused a crisis at the Fukushima Daiichi nuclear power station where it overtopped the seawall defences. On retreating, the tsunami carried loose debris and wreckage seaward and marshalled buoyant material into extensive plumes. Widespread concern over the fate of these and numerous other Tōhoku tsunami depositions prompted attempts to simulate debris dispersion throughout the wider Pacific. However, the effects of locally perturbed wind and wave fields, active Langmuir circulation and current-induced attrition determine a complex and poorly understood morphology for large floating agglomerations. Here we show that the early post-tsunami evolution of marine-debris plumes near Fukushima Daiichi was also shaped by near-surface wind modifications that took place above relatively calm (lower surface roughness) waters covered by surface films derived from oil and other contaminants. High-spatial-resolution satellite tracking reveals faster-than-expected floating-debris motions and invigorated plume evolution within these regions, while numerical modelling of turbulent air flow over the low-drag, film-covered surface predicts typically metre-per-second wind strengthening at centimetric heights, sufficient to explain the observed debris-speed increases. Wind restructuring probably stimulates the dispersion of flotsam from both biological and anthropogenic sources throughout a global ocean of highly variable surface roughness.

Calibrated Blade-Element/Momentum Theory Aerodynamic Model of the MARIN Stock Wind Turbine: Preprint

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

Goupee, A.; Kimball, R.; de Ridder, E. J.

2015-04-02

In this paper, a calibrated blade-element/momentum theory aerodynamic model of the MARIN stock wind turbine is developed and documented. The model is created using open-source software and calibrated to closely emulate experimental data obtained by the DeepCwind Consortium using a genetic algorithm optimization routine. The provided model will be useful for those interested in validating interested in validating floating wind turbine numerical simulators that rely on experiments utilizing the MARIN stock wind turbine—for example, the International Energy Agency Wind Task 30’s Offshore Code Comparison Collaboration Continued, with Correlation project.

Buttressing and stability of marine Ice sheets

NASA Astrophysics Data System (ADS)

Goldberg, D.; Holland, D. M.; Schoof, C.

2009-04-01

The West Antarctic Ice Sheet is marine in nature, meaning most of its base is below sea level. At the grounding line (where it becomes thin enough to float), its outlet streams flow into large ice shelves. Gravitational stress in the shelf is transmitted back to the grounding line, and largely balanced by basal friction in the transition zone. The details of this force balance control the evolution of both the thickness and grounded extent of the ice sheet, and can lead to Weertman's (1974) Marine Instability for a foredeepened bedrock (one that deepens inland). However, the presence of rigid sidewalls and locally grounded regions in the shelf can reduce the longitudinal stresses felt at the grounding line (a phenomenon called buttressing). Thomas (1979) and others pointed out that Marine Instability may be lessened or reversed by ice shelf buttressing. When modelling marine ice sheets numerically, the physics of the grounded-to-floating transition must be represented and the associated small length scales must be resolved (Schoof, 2007). Failing to do so can result in nonphysical or numerically inconsistent behavior (Vieli and Payne, 2005). While several methods have been developed to treat these issues (Vieli and Payne, 2005; Pattyn et al, 2006; Schoof, 2007) they are limited to flowline models. We present a model that represents the physics of the grounded-to-floating transition in a time-dependent three-dimensional marine ice sheet, using mesh adaption to resolve the transition zone. We show that in the special case of a two-dimensional sheet our model reproduces the theoretical results of the MISMIP experiments, and that it produces robust results when both horizontal dimensions are resolved. In idealized experiments in a channel with rigid sidewalls and a foredeepened bed, we narrow the channel to determine whether buttressing is sufficient to reverse instability. We find that for strong beds (high friction coefficients), while the timescales and dynamics are affected greatly by buttressing, true stability reversal is still not seen even as the channel becomes quite narrow. However, for weaker beds, stability is seen, though it can be shown that sufficient ocean melting can still cause collapse. Experiments with more complicated bed topography show that locally grounded areas (ice rises) have similar dynamic effects to rigid sidewalls.

Unusual fast-growing ovarian cystic teratoma during pregnancy presenting with intracystic fat "floating balls" appearance.

PubMed

Donnadieu, Anne Claire; Deffieux, Xavier; Le Ray, Camille; Mordefroid, Marie; Frydman, René; Fernandez, Hervé

2006-12-01

A large ovarian cyst was diagnosed at 22 weeks' of gestation in a 32-year-old woman. The ultrasonographic appearance of the ovarian cyst was unusual with multiple mobile, spherical echogenic structures floating in the cystic mass, called intracystic "fat balls." Right adnexectomy was performed by laparotomy at 28 weeks' of gestation, because of rapid growth and overall size exceeding 20 cm. Pathological examination confirmed ovarian cystic teratoma. Usually, dermoid cysts are slow-growing, even in premenopausal women. The exact mechanism related to the fast growth during pregnancy is unknown. It could be related to an unusual pattern of estrogen (E)/P receptors expression in the cystic teratoma. This case shows that a fast-growing, mature ovarian cystic teratoma may occur during pregnancy.

The boundary current role on the transport and stranding of floating marine litter: The French Riviera case

NASA Astrophysics Data System (ADS)

Ourmieres, Yann; Mansui, Jérémy; Molcard, Anne; Galgani, François; Poitou, Isabelle

2018-03-01

The aim of the present study is to evidence the role of a boundary current and meteorological conditions in the transport and stranding of floating marine debris. The used data are from a beach survey and an inter-annual unique effort of marine debris sightings along the French Riviera in the North-Western Mediterranean region. Offshore data have been collected during oceanic cruises while beach surveys were performed around Antibes city. Debris were found on 97% of the ocean transects, with a large spatial and temporal variability, showing contrasted areas of low ( 1 item/km2) and of high (> 10 items/km2) debris densities. Results suggest that the debris spatio-temporal distribution is related to the Northern current (NC) dynamics, the regional boundary current, with accumulation patterns in its core and external edge. By playing a role in the alongshore transport, such a boundary current can form a cross-shore transport barrier. Stranding events can then occur after strong on-shore wind bursts modifying the sea surface dynamics and breaking this transport barrier. It is also shown that episodic enhancement of the stranding rate can be explained by combining the NC dynamics with the wind forcing and the rainfall effect via the local river run-off. Conversely, off-shore wind bursts could also free the marine litter from the boundary current and export them towards the open sea.

Floating Classroom Outreach as an Introduction to Ocean Studies

NASA Astrophysics Data System (ADS)

McFadden, M.

2016-02-01

Many children and young adults living within only one hour of the coast never have the opportunity to explore a beach or go out on a boat because of financial challenges or lack of transportation.These types of experiences are the spark that helped many ocean scientists become fascinated with the ocean and later pursue a career related to the ocean. This presentation will discuss a variety of outreach projects and the efficacy of each. Projects vary in age, complexity and cost. These projects include a Beach Clean-Up open to students and their families at a community college organized by a campus volunteer group with a focus on social issues, a Marine Biology and Physical Oceanography class joint floating classroom trip open to college students to introduce non-STEM students to marine science in an exciting setting, and an education outreach trip for 8-12 years old children from the Boys and Girls Club in Newport, RI in collaboration with The International SeaKeepers Society, a non-profit that facilitates ocean research and education by working closely with the yachting community. Emphasis on environmental education in the U.S. has grown considerably over recent years, and the development of unique and innovative approaches to hands-on marine science education are needed to excite students to explore the marine environment and care about environmental stewardship.

Analysis of Skylab IV fluid mechanic science demonstration

NASA Technical Reports Server (NTRS)

Klett, M. G.; Bourgeois, S. V.

1975-01-01

Several science demonstrations performed on Skylab III and IV were concerned with the behavior of fluid drops free floating in microgravity. These demonstrations, with large liquid drops, included the oscillation, rotation, impact and coalescence, and air injection into the drops. Rayleigh's analysis of the oscillation of spherical drops of a liquid predicts accurately the effect of size and surface tension on the frequency of vibrated water globules in the Skylab demonstration. However, damping occurred much faster than predicted by Lamb's or Scriven's analyses of the damping time for spherical drops. The impact demonstrations indicated that a minimum velocity is necessary to overcome surface forces and effect a coalescence, but a precise criterion for the coalescence of liquids in low g could not be determined.

Teachers Guide.

ERIC Educational Resources Information Center

Linsky, Ronald B.; Schnitger, Ronald L.

This guide provides teachers with copies of the materials given to students participating in the oceanography program of the Orange County Floating Laboratory Program and provides information concerning colleges and universities offering courses in oceanography and marine science, source of films, and sources of publications concerning the Navy's…

Using the Data From Accidents and Natural Disasters to Improve Marine Debris Modeling

NASA Astrophysics Data System (ADS)

Maximenko, N. A.; Hafner, J.; MacFadyen, A.; Kamachi, M.; Murray, C. C.

2016-02-01

In the absence of satisfactory marine debris observing system, drift models provide a unique tool that can be used to identify main pathways and accumulation areas of the natural and anthropogenic debris, including the plastic pollution having increasing impact on the environment and raising concern of the society. Main problems, limiting the utility of model simulations, include the lack of accurate information on distribution, timing, strength and composition of sources of marine debris and the complexity of the hydrodynamics of an object, floating on the surface of a rough sea. To calculate the drift, commonly, models estimate surface currents first and then add the object motion relative to the water. Importantly, ocean surface velocity can't be measured with the existing instruments. For various applications it is derived from subsurface (such as 15-meter drifter trajectories) and satellite (altimetry, scatterometry) data using simple theories (geostrophy, Ekman spiral, etc.). Similarly, even the best ocean general circulation models (OGCM's), utilizing different parameterizations of the mixed layer, significantly disagree on the ocean surface velocities. Understanding debris motion under the direct wind force and in interaction with the breaking wind waves seems to be a task of even greater complexity. In this presentation, we demonstrate how the data of documented natural disasters (such as tsunamis, hurricanes and floods) and other accidents generating marine debris with known times and coordinates of start and/or end points of the trajectories, can be used to calibrate drift models and obtain meaningful quantitative results that can be generalized for other sources of debris and used to plan the future marine debris observing system. On these examples we also demonstrate how the oceanic and atmospheric circulations couple together to determine the pathways and destination areas of different types of the floating marine debris.

Morphology, seasonality and phylogeny of Zschokkella trachini n. sp. (Myxozoa, Myxosporea) infecting the gallbladder of greater weever Trachinus draco (L.) from Tunisian waters.

PubMed

Azizi, Ramla; Rangel, Luis F; Castro, Ricardo; Santos, Maria J; Bahri, Sihem

2016-11-01

We describe a new myxosporean species, Zschokkella trachini n. sp., infecting the gallbladder of greater weever Trachinus draco Linnaeus 1758 from Tunisia. This is the first record of Zschokkella species in T. draco. Plasmodia were polysporic producing six to eight mature spores; they were attached to the gallbladder epithelium or free floating in the bile. Mature spores were sub-ovoid in the frontal view, measured 15.2 ± 0.6 (14.4-16.0) μm in length and 9.8 ± 0.7 (9.0-10.8) μm in width. Two equal spherical polar capsules 4.0 ± 0.4 (3.6-4.5) μm in diameter, were located separately at the spore's extremities. The prevalence of infection ranged from 23.5 to 87.7 %. Morphological data and molecular analysis of the small subunit rDNA gene identified this parasite as a new species of Zschokkella. Neighbour joining clustered the parasite in a sub-clade containing other Zschokkella species parasiting the gallbladder of marine fish hosts, located within the coelozoic clade of the major freshwater clade. This is the second Zschokkella species reported from Tunisia.

33 CFR 159.3 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... centerline. Bow sprits, bumpkins, rudders, outboard motor brackets, and similar fittings or attachments are... milliliters and no visible floating solids. Type II marine sanitation device means a device that, under the... bacteria count not greater than 200 per 100 milliliters and suspended solids not greater than 150...

33 CFR 159.3 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... centerline. Bow sprits, bumpkins, rudders, outboard motor brackets, and similar fittings or attachments are... milliliters and no visible floating solids. Type II marine sanitation device means a device that, under the... bacteria count not greater than 200 per 100 milliliters and suspended solids not greater than 150...

33 CFR 159.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... centerline. Bow sprits, bumpkins, rudders, outboard motor brackets, and similar fittings or attachments are... milliliters and no visible floating solids. Type II marine sanitation device means a device that, under the... bacteria count not greater than 200 per 100 milliliters and suspended solids not greater than 150...

Benthic assemblages, biodiversity and invasiveness in marinas and commercial harbours: an investigation using a bioindicator group.

PubMed

Megina, Cesar; González-Duarte, Manuel M; López-González, Pablo J

2016-01-01

Fouling communities on artificial marine structures are generally different from benthic communities in natural rocky habitats. However, they may also differ among different types of artificial structures. Two artificial structures in direct contact with arriving vessels were compared: floating pontoons within recreational marinas, and sea-walls within commercial harbours. Natural rocky habitats were used as a reference, and the genus Eudendrium (Cnidaria, Hydrozoa) was chosen as a bioindicator. The assemblages were different among the three types of habitat studied, with different species characterising each habitat. The probability of finding an invasive Eudendrium species was significantly higher on pontoons. Diversity was the lowest on pontoons, but it was not significantly different between sea-walls and natural rocks. In general, a barrier to the spread of exotic species exists between harbours and natural rocky habitats. Floating pontoons seem to be a less suitable habitat for native fauna and a key element in marine biological invasions.

Floating marine debris in coastal waters of the SE-Pacific (Chile).

PubMed

Thiel, M; Hinojosa, I; Vásquez, N; Macaya, E

2003-02-01

Herein we report on the abundance and composition of floating marine debris (FMD) in coastal waters of the SE-Pacific (off the Chilean coast) during the austral summer 2002. The observed FMD consisted mainly of plastic material (86.9%). Densities of FMD were highest between 20 degrees S and 40 degrees S, corresponding to the main concentrations of human population and activities. Low densities of FMD were found in the south between 40 degrees S and 50 degrees S (<1 item km(-2)). Generally, the highest densities were recorded in nearshore waters of major port cities (>20 items km(-2)), but occasionally high concentrations of debris were also found 50 km offshore. Densities of FMD in coastal waters of the SE-Pacific are of similar magnitudes as those found in coastal waters or inland seas of highly populated regions in the northern hemisphere, indicating the need for improved regulation and legislation in the countries of the SE-Pacific.

Physical measurements of breaking wave impact on a floating wave energy converter

NASA Astrophysics Data System (ADS)

Hann, Martyn R.; Greaves, Deborah M.; Raby, Alison

2013-04-01

Marine energy converter must both efficiently extract energy in small to moderate seas and also successfully survive storms and potential collisions. Extreme loads on devices are therefore an important consideration in their design process. X-MED is a SuperGen UKCMER project and is a collaboration between the Universities of Manchester, Edinburgh and Plymouth and the Scottish Association for Marine Sciences. Its objective is to extend the knowledge of extreme loads due to waves, currents, flotsam and mammal impacts. Plymouth Universities contribution to the X-MED project involves measuring the loading and response of a taut moored floating body due to steep and breaking wave impacts, in both long crested and directional sea states. These measurements are then to be reproduced in STAR-CCM+, a commercial volume of fluid CFD solver, so as to develop techniques to predict the wave loading on wave energy converters. The measurements presented here were conducted in Plymouth Universities newly opened COAST laboratories 35m long, 15.5m wide and 3m deep ocean basin. A 0.5m diameter taut moored hemispherical buoy was used to represent a floating wave energy device or support structure. The changes in the buoys 6 degree of freedom motion and mooring loads are presented due to focused breaking wave impacts, with the breaking point of the wave changed relative to the buoy.

An inexpensive instrument for measuring wave exposure and water velocity

USGS Publications Warehouse

Figurski, J.D.; Malone, D.; Lacy, J.R.; Denny, M.

2011-01-01

Ocean waves drive a wide variety of nearshore physical processes, structuring entire ecosystems through their direct and indirect effects on the settlement, behavior, and survivorship of marine organisms. However, wave exposure remains difficult and expensive to measure. Here, we report on an inexpensive and easily constructed instrument for measuring wave-induced water velocities. The underwater relative swell kinetics instrument (URSKI) is a subsurface float tethered by a short (<1 m) line to the seafloor. Contained within the float is an accelerometer that records the tilt of the float in response to passing waves. During two field trials totaling 358 h, we confirmed the accuracy and precision of URSKI measurements through comparison to velocities measured by an in situ acoustic Doppler velocimeter and those predicted by a standard swell model, and we evaluated how the dimensions of the devices, its buoyancy, and sampling frequency can be modified for use in a variety of environments.

Genetic variation of Sargassum horneri populations detected by inter-simple sequence repeats.

PubMed

Ren, J R; Yang, R; He, Y Y; Sun, Q H

2015-01-30

The seaweed Sargassum horneri is an important brown alga in the marine environment, and it is an important raw material in the alginate industry. Unfortunately, the fixed resource that was originally reported is now reduced or disappeared, and increased floating populations have been reported in recent years. We sampled a floating population and 4 fixed cultivated populations of S. horneri along the coast of Zhejiang, China. Inter-simple sequence repeat (ISSR) markers were applied in this research to analyze the genetic variation between floating populations and fixed cultivated populations of S. horneri. In total, 220 loci were amplified with 23 ISSR primers. The percentage of polymorphic loci within each population ranged from 53.64 to 95.45%. The highest diversity was observed in population 3, which was the local species that was suspension cultured in the lab and then fixed cultivated in the Nanji Islands before sampling. The lowest diversity was obtained in the floating population 4. The genetic distances among the 5 S. horneri populations ranged from 0.0819 to 0.2889, and the distance tendency confirmed the genetic diversity. The results suggest that the floating population had the lowest genetic diversity and could not be joined into the cluster branch of the fixed cultivated populations.

46 CFR 108.530 - Stowage of survival craft.

Code of Federal Regulations, 2013 CFR

2013-10-01

... craft required to be served by a launching appliance or marine evacuation system must be stowed as.... (5) Each rigid container for an inflatable liferaft to be launched by a launching appliance must be... arranged for float-free launching. The arrangement must ensure that the liferaft or liferafts when released...

Support mechanism for a mirrored surface or other arrangement and method

DOEpatents

Cutburth, R.W.

1985-11-08

An adjustment mechanism such as a three point spherical mount for adjustably supporting a planer mirror or other type of arrangement relative to a plane defined by a given pair of perpendicular axes is described in this disclosure. This mechanism provides for positioning within the plane defined by the given pair of intersecting perpendicular axes. Limited positioning is possible about either of these axes and provides for a ''non-floating'' center of adjustment.

Toxicological effects of irregularly shaped and spherical microplastics in a marine teleost, the sheepshead minnow (Cyprinodon variegatus).

PubMed

Choi, Jin Soo; Jung, Youn-Joo; Hong, Nam-Hui; Hong, Sang Hee; Park, June-Woo

2018-04-01

The increasing global contamination of plastics in marine environments is raising public concerns about the potential hazards of microplastics to environmental and human health. Microplastics formed by the breakdown of larger plastics are typically irregular in shape. The objective of this study was to compare the effects of spherical or irregular shapes of microplastics on changes in organ distribution, swimming behaviors, gene expression, and enzyme activities in sheepshead minnow (Cyprinodon variegatus). Both types of microplastics accumulated in the digestive system, causing intestinal distention. However, when compared to spherical microplastics, irregular microplastics decreased swimming behavior (i.e., total distance travelled and maximum velocity) of sheepshead minnow. Both microplastics generated cellular reactive oxygen species (ROS), while ROS-related molecular changes (i.e., transcriptional and enzymatic characteristics) differed. This study provides toxicological insights into the impacts of environmentally relevant (fragmented) microplastics on fish and improves our understanding of the environmental effects of microplastics in the ecosystem. Copyright © 2018 Elsevier Ltd. All rights reserved.

Mediterranean marine biodiversity under threat: Reviewing influence of marine litter on species.

PubMed

Deudero, Salud; Alomar, Carme

2015-09-15

The Mediterranean Sea is one of the most polluted seas worldwide, especially with regard to plastics. The presence of this emerging man made contaminant in marine environments precludes large effects and interactions with species exposed to massive litter quantities. In this review, available data of floating and seafloor litter around Mediterranean sub-basins are reported. A review of scientific literature on the interaction of plastic with marine biota resulted in the identification of 134 species, several taxa and feeding strategies affected from 1986 to 2014. Data from 17,334 individuals showed different levels of ingestion and effects on catalogued IUCN species (marine mammals and sea turtles) in addition to several pelagic fish and elasmobranchs. Biodiversity is certainly under threat, and knowledge of the extent of taxa affected is of concern considering the increasing plastic loads in the Mediterranean Sea and worldwide. Copyright © 2015 Elsevier Ltd. All rights reserved.

Generalized fluid impulse functions for oscillating marine structures

NASA Astrophysics Data System (ADS)

Janardhanan, K.; Price, W. G.; Wu, Y.

1992-03-01

A selection of generalized impulse response functions is presented for a variety of rigid and flexible marine structures (i.e. mono-hull, SWATH, floating drydock and twin dock, fixed flexible pile). These functions are determined from calculated and experimental frequency-dependent hydrodynamic data, and the characteristics of these data depend on the type of structure considered. This information is reflected in the shape and duration of the generalized impulse response functions which are pre-requisites for a generalized integro-differential mathematical model describing the dynamic behaviour of the structures to seaway excitation.

Floating dosage forms to prolong gastro-retention--the characterisation of calcium alginate beads.

PubMed

Stops, Frances; Fell, John T; Collett, John H; Martini, Luigi G

2008-02-28

Floating calcium alginate beads, designed to improve drug bioavailability from oral preparations compared with that from many commercially available and modified release products, have been investigated as a possible gastro-retentive dosage form. A model drug, riboflavin, was also incorporated into the formula. The aims of the current work were (a) to obtain information regarding the structure, floating ability and changes that occurred when the dosage form was placed in aqueous media, (b) to investigate riboflavin release from the calcium alginate beads in physiologically relevant media prior to in vivo investigations. Physical properties of the calcium alginate beads were investigated. Using SEM and ESEM, externally the calcium alginate beads were spherical in shape, and internally, air filled cavities were present thereby enabling floatation of the beads. The calcium alginate beads remained buoyant for times in excess of 13h, and the density of the calcium alginate beads was <1.000gcm(-3). Riboflavin release from the calcium alginate beads showed that riboflavin release was slow in acidic media, whilst in more alkali media, riboflavin release was more rapid. The characterisation studies showed that the calcium alginate beads could be considered as a potential gastro-retentive dosage form.

76 FR 6406 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to a...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-04

... be present during the project's timeline may be exposed to sound pressure levels associated with... of the wharf's existing piling sub-structure. Under the proposed action, ninety-six 24-in (0.6 m... loss formulas (the practical spreading loss equation for underwater sounds and the spherical spreading...

Ultra-high Q terahertz whispering-gallery modes in a silicon resonator

NASA Astrophysics Data System (ADS)

Vogt, Dominik Walter; Leonhardt, Rainer

2018-05-01

We report on the first experimental demonstration of terahertz (THz) whispering-gallery modes (WGMs) with an ultra-high quality factor of 1.5 × 104 at 0.62 THz. The WGMs are observed in a high resistivity float zone silicon spherical resonator coupled to a sub-wavelength silica waveguide. A detailed analysis of the coherent continuous wave THz spectroscopy measurements combined with a numerical model based on Mie-Debye-Aden-Kerker theory allows us to unambiguously identify the observed higher order radial THz WGMs.

A measurement of the energy spectra of cosmic rays from 20 to 1000 GeV per AMU

NASA Technical Reports Server (NTRS)

Gregory, John C.; Smith, Arthur

1994-01-01

During the report period the BUGS-4 instrument was completed, and the maiden voyage took place on 29 September from Fort Sumner, New Mexico. The successful flight of a large spherical drift chamber is a unique first for the sub-orbital balloon program. Unfortunately the instrument was consumed by fire after striking a power line during landing. However, while at float altitude, circa 24 hours of data were telemetered. The pre-flight preparations, and flight operations are described.

Marine Exposure of Preservative-Treated Small Wood Panels.

DTIC Science & Technology

1981-04-01

southern noria attack and that creosote impedes teredine attack, pine sapwood , 0.24 to 0.39 growth rings per mm (6-8/in.), a study was initiated in 1969...whereas in piling, wave action and abrasion from The column showing "months exposure to index below floating debris must break away surface areas to

Small Flux Buoy for Characterizing Marine Surface Layers

DTIC Science & Technology

2013-06-01

platform for air-sea interaction study since early 1960s (Fisher and Spiess 1963). It was designed to be a stable platform for mounting various types of...COARE algorithm. J. of Climate, 16, 571–591. Fisher F. H., and F. N. Spiess , 1963: FLIP-floating instrument platform. J. Acoust. Soc. Am., 35, 1633

The Quasi-Eulerian Hydrophone: A New Approach for Ocean Acoustics

NASA Astrophysics Data System (ADS)

Matsumoto, H.; Dziak, R. P.; Fowler, M. J.; Hammond, S. R.; Meinig, C.

2005-12-01

For the last 10 years Oregon State University and NOAA/Pacific Marine Environmental Laboratory have successfully operated and maintained autonomous hydrophone arrays to monitor low frequency acoustic energy of earthquakes and marine mammal calls in remote ocean areas where no historical record existed. These hydrophones are moored at mid-water depth and require a routine servicing cruise to retrieve the stored data. The system is robust, but it is not real-time and it takes up to a year before acoustic events can be identified from the raw acoustic data. As a result, we frequently miss opportunities to observe ocean acoustic events as they occur. A new type of autonomous hydrophone called a Quasi-Eulerian hydrophone (QUEphone) is under development at OSU/PMEL. This instrument allows near-real-time monitoring of a selected study area. It is a tether-free float with a built-in hydrophone monitoring system and a buoyancy controller. It is capable of repeat ascent/descent cycles in up to 2000 m of water. In contrast to the conventional Lagrangean float, the QUEphone float stays in the same area by maintaining negative buoyancy and remaining on the seafloor for most of its life span. While on the seafloor the QUEphone runs an intelligent event detection algorithm, and upon detection of a significant number of events will surface to transmit a small data file to shore. We have conducted brief test deployments of the QUEphone in both a fresh-water lake and marine waters off Oregon coast, and the results of these tests will be discussed and compared with other hydrophone data. Once fully developed the QUEphone is expected to provide near real-time analysis capability of earthquakes that affect seafloor hydrothermal vents and their associated ecosystems. Such fast reaction will allow for a rapid response to seismic events, enabling researchers to examine how changes in hydrothermal activity affect deep-ocean vent ecosystems.

Modelling global distribution, risk and mitigation strategies of floating plastic pollution

NASA Astrophysics Data System (ADS)

van Sebille, Erik; Wilcox, Chris; Sherman, Peter; Hardesty, Britta Denise; Lavender Law, Kara

2016-04-01

Microplastic debris floating at the ocean surface can harm marine life. Understanding the severity of this harm requires knowledge of plastic abundance and distributions. Dozens of expeditions measuring microplastics have been carried out since the 1970s, but they have primarily focused on the North Pacific and North Atlantic accumulation zones, with much sparser coverage elsewhere. Here, we use the largest dataset of microplastic measurements assembled to date to assess the confidence we can have in global estimates of microplastic abundance and mass. We use a rigorous statistical framework to standardise a global dataset of plastic marine debris measured using surface-trawling plankton nets and couple this with three different ocean circulation models to spatially interpolate the observations. Our estimates show that the accumulated number of microplastic particles in 2014 ranges from 15 to 51 trillion particles, weighing between 93 and 236 thousand metric tons. A large fraction of the uncertainty in these estimates comes from sparse sampling in coastal and Southern Hemisphere regions. We then use this global distribution of small floating plastic debris to map out where in the ocean the risk to marine life (in particular seabirds and plankton growth) is greatest, using a quantitative risk framework. We show that the largest risk occurs not necessarily in regions of high plastic concentration, but rather in regions of extensive foraging with medium-high plastic concentrations such as coastal upwelling regions and the Southern Ocean. Finally, we use the estimates of distribution to investigate where in the ocean plastic can most optimally be removed, assuming hypothetical clean-up booms following the ideas from The Ocean Cleanup project. We show that mitigation of the plastic problem can most aptly be done near coastlines, particularly in Asia, rather than in the centres of the gyres. Based on these results, we propose more focus on the coastal zones when considering future efforts in sampling, risk management and mitigation.

Early post-mortem formation of carbonate concretions around tusk-shells over week-month timescales

NASA Astrophysics Data System (ADS)

Yoshida, Hidekazu; Ujihara, Atsushi; Minami, Masayo; Asahara, Yoshihiro; Katsuta, Nagayoshi; Yamamoto, Koshi; Sirono, Sin-Iti; Maruyama, Ippei; Nishimoto, Shoji; Metcalfe, Richard

2015-09-01

Carbonate concretions occur in sedimentary rocks of widely varying geological ages throughout the world. Many of these concretions are isolated spheres, centered on fossils. The formation of such concretions has been variously explained by diffusion of inorganic carbon and organic matter in buried marine sediments. However, details of the syn-depositional chemical processes by which the isolated spherical shape developed and the associated carbon sources are little known. Here we present evidence that spherical carbonate concretions (diameters φ : 14 ~ 37 mm) around tusk-shells (Fissidentalium spp.) were formed within weeks or months following death of the organism by the seepage of fatty acid from decaying soft body tissues. Characteristic concentrations of carbonate around the mouth of a tusk-shell reveal very rapid formation during the decay of organic matter from the tusk-shell. Available observations and geochemical evidence have enabled us to construct a ‘Diffusion-growth rate cross-plot’ that can be used to estimate the growth rate of all kinds of isolated spherical carbonate concretions identified in marine formations. Results shown here suggest that isolated spherical concretions that are not associated with fossils might also be formed from carbon sourced in the decaying soft body tissues of non-skeletal organisms with otherwise low preservation potential.

Capture, swallowing, and egestion of microplastics by a planktivorous juvenile fish.

PubMed

Ory, Nicolas Christian; Gallardo, Camila; Lenz, Mark; Thiel, Martin

2018-09-01

Microplastics (<5 mm) have been found in many fish species, from most marine environments. However, the mechanisms underlying microplastic ingestion by fish are still unclear, although they are important to determine the pathway of microplastics along marine food webs. Here we conducted experiments in the laboratory to examine microplastic ingestion (capture and swallowing) and egestion by juveniles of the planktivorous palm ruff, Seriolella violacea (Centrolophidae). As expected, fish captured preferentially black microplastics, similar to food pellets, whereas microplastics of other colours (blue, translucent, and yellow) were mostly co-captured when floating close to food pellets. Microplastics captured without food were almost always spit out, and were only swallowed when they were mixed with food in the fish's mouth. Food probably produced a 'gustatory trap' that impeded the fish to discriminate and reject the microplastics. Most fish (93% of total) egested all the microplastics after 7 days, on average, and 49 days at most, substantially longer than food pellets (<2 days). No acute detrimental effects of microplastics on fish were observable, but potential sublethal effects of microplastics on the fish physiological and behavioural responses still need to be tested. This study highlights that visually-oriented planktivorous fish, many species of which are of commercial value and ecological importance within marine food webs, are susceptible to ingest microplastics resembling or floating close to their planktonic prey. Copyright © 2018 Elsevier Ltd. All rights reserved.

Investigating the potential of floating mires as record of palaeoenvironmental changes

NASA Astrophysics Data System (ADS)

Zaccone, C.; Adamo, P.; Giordano, S.; Miano, T. M.

2012-04-01

Peat-forming floating mires could provide an exceptional resource for palaeoenvironmental and environmental monitoring studies, as much of their own history, as well as the history of their surrounds, is recorded in their peat deposits. In his Naturalis historia (AD 77-79), Pliny the Elder described floating islands on Lake Vadimonis (now Posta Fibreno Lake, Italy). Actually, a small floating island (ca. 35 m of diameter and 3 m of submerged thickness) still occurs on this calcareous lake fed by karstic springs at the base of the Apennine Mountains. Here the southernmost Italian populations of Sphagnum palustre occur on the small surface of this floating mire known as "La Rota", i.e., a cup-formed core of Sphagnum peat and rhizomes of Helophytes, erratically floating on the water-body of a submerged doline, annexed to the easternmost edge of the lake, characterised by the extension of a large reed bed. Geological evidence point out the existence in the area of a large lacustrine basin since Late Pleistocene. The progressive filling of the lake caused by changing in climatic conditions and neotectonic events, brought about the formation of peat deposits in the area, following different depositional cycles in a swampy environment. Then, a round-shaped portion of fen, originated around lake margins in waterlogged areas, was somehow isolated from the bank and started to float. Coupling data about concentrations and fluxes of several major and trace elements of different origin (i.e., dust particles, volcanic emissions, cosmogenic dusts and marine aerosols), with climate records (plant micro- and macrofossils, pollens, isotopic ratios), biomolecular records (e.g., lipids), detailed age-depth modelling (i.e., 210Pb, 137Cs, 14C), and humification indexes, the present work is hoped to identify and better understand the reliability of this particular "archive", and thus possible relationships between biogeochemical processes occurring in this floating bog and environmental changes.

Electrical Components for Marine Renewable Energy Arrays: A Techno-Economic Review

DOE PAGES

Collin, Adam J.; Nambiar, Anup J.; Bould, David; ...

2017-11-27

This paper presents a review of the main electrical components that are expected to be present in marine renewable energy arrays. The review is put in context by appraising the current needs of the industry and identifying the key components required in both device and array-scale developments. For each component, electrical, mechanical and cost considerations are discussed; with quantitative data collected during the review made freely available for use by the community via an open access online repository. Here, this data collection updates previous research and addresses gaps specific to emerging offshore technologies, such as marine and floating wind, andmore » provides a comprehensive resource for the techno-economic assessment of offshore energy arrays.« less

Electrical Components for Marine Renewable Energy Arrays: A Techno-Economic Review

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

Collin, Adam J.; Nambiar, Anup J.; Bould, David

This paper presents a review of the main electrical components that are expected to be present in marine renewable energy arrays. The review is put in context by appraising the current needs of the industry and identifying the key components required in both device and array-scale developments. For each component, electrical, mechanical and cost considerations are discussed; with quantitative data collected during the review made freely available for use by the community via an open access online repository. Here, this data collection updates previous research and addresses gaps specific to emerging offshore technologies, such as marine and floating wind, andmore » provides a comprehensive resource for the techno-economic assessment of offshore energy arrays.« less

Modelling the transport and accumulation of floating marine debris in the Mediterranean basin.

PubMed

Mansui, J; Molcard, A; Ourmières, Y

2015-02-15

In the era of plastic and global environmental issues, when large garbage patches have been observed in the main oceanic basins, this work is the first attempt to explore the possibility that similar permanent accumulation structures may exist in the Mediterranean Sea. The questions addressed in this work are: can the general circulation, with its sub-basins scale gyres and mesoscale instabilities, foster the concentration of floating items in some regions? Where are the more likely coastal zones impacted from open ocean sources? Multi-annual simulations of advected surface passive debris depict the Tyrrhenian Sea, the north-western Mediterranean sub-basin and the Gulf of Sirte as possible retention areas. The western Mediterranean coasts present very low coastal impact, while the coastal strip from Tunisia to Syria appears as the favourite destination. No permanent structure able to retain floating items in the long-term were found, as the basin circulation variability brings sufficient anomalies. Copyright © 2014 Elsevier Ltd. All rights reserved.

Floating marine debris surface drift: convergence and accumulation toward the South Pacific subtropical gyre.

PubMed

Martinez, Elodie; Maamaatuaiahutapu, Keitapu; Taillandier, Vincent

2009-09-01

Whatever its origin is, a floating particle at the sea surface is advected by ocean currents. Surface currents could be derived from in situ observations or combined with satellite data. For a better resolution in time and space, we use satellite-derived sea-surface height and wind stress fields with a 1/3 degrees grid from 1993 to 2001 to determine the surface circulation of the South Pacific Ocean. Surface currents are then used to compute the Lagrangian trajectories of floating debris. Results show an accumulation of the debris in the eastern-centre region of the South Pacific subtropical gyre ([120 degrees W; 80 degrees W]-[20 degrees S; 40 degrees S]), resulting from a three-step process: in the first two years, mostly forced by Ekman drift, the debris drift towards the tropical convergence zone ( approximately 30 degrees S). Then they are advected eastward mostly forced by geostrophic currents. They finally reach the eastern-centre region of the South Pacific subtropical gyre from where they could not escape.

Boring crustaceans damage polystyrene floats under docks polluting marine waters with microplastic.

PubMed

Davidson, Timothy M

2012-09-01

Boring isopods damage expanded polystyrene floats under docks and, in the process, expel copious numbers of microplastic particles. This paper describes the impacts of boring isopods in aquaculture facilities and docks, quantifies and discusses the implications of these microplastics, and tests if an alternate foam type prevents boring. Floats from aquaculture facilities and docks were heavily damaged by thousands of isopods and their burrows. Multiple sites in Asia, Australia, Panama, and the USA exhibited evidence of isopod damage. One isopod creates thousands of microplastic particles when excavating a burrow; colonies can expel millions of particles. Microplastics similar in size to these particles may facilitate the spread of non-native species or be ingested by organisms causing physical or toxicological harm. Extruded polystyrene inhibited boring, suggesting this foam may prevent damage in the field. These results reveal boring isopods cause widespread damage to docks and are a novel source of microplastic pollution. Copyright © 2012 Elsevier Ltd. All rights reserved.

Euro-Argo: The European contribution to the global Argo ocean observations network

NASA Astrophysics Data System (ADS)

Gourcuff, Claire

2017-04-01

The international Argo programme is a major element of the global in-situ ocean observing system. More than 3900 floats are now globally measuring temperature and salinity throughout the global oceans, down to 2,000 meters depth and delivering data both in real time for operational users and after careful scientific quality control for climate change research and monitoring. Argo is the single most important in-situ observing system for the Copernicus Marine Service. The Euro-Argo research infrastructure organizes and federates European contribution to Argo. A legal and governance framework (Euro-Argo ERIC) was set up in May 2014; it allows European countries to consolidate and improve their contribution to Argo international. We will provide an overview of the development of Euro-Argo over the past years and present the now agreed Euro-Argo long term organization. The capability of the Euro-Argo infrastructure to organize Argo floats procurement, deployment and processing at European level and to conduct R&D driven by Copernicus needs will be highlighted. During the recent years, within the H2020 E-AIMS project, Euro-Argo carried R&D activities on new Argo floats, equipped with biogeochemical sensors or able to dive up to 4000m, from the floats design up to the analysis of their measurements. European Argo data centers were adapted so that they can handle the new data. Observing System Evaluations and Simulation Experiments were also conducted to provide robust recommendations for the next phase of Argo. One of the main challenges for Euro-Argo is now to implement the next phase of Argo with an extension towards biogeochemistry (e.g. oxygen, biology), the polar oceans, the marginal seas and the deep ocean. Meeting such challenges is essential for the long term sustainability and evolution of the Copernicus Marine Service. We will present Euro-Argo strategy and provide some highlights on the implementation-plan for the years to come and the Argo extensions for the next decade.

Dissolved organic carbon leaching from plastics stimulates microbial activity in the ocean.

PubMed

Romera-Castillo, Cristina; Pinto, Maria; Langer, Teresa M; Álvarez-Salgado, Xosé Antón; Herndl, Gerhard J

2018-04-12

Approximately 5.25 trillion plastic pieces are floating at the sea surface. The impact of plastic pollution on the lowest trophic levels of the food web, however, remains unknown. Here we show that plastics release dissolved organic carbon (DOC) into the ambient seawater stimulating the activity of heterotrophic microbes. Our estimates indicate that globally up to 23,600 metric tons of DOC are leaching from marine plastics annually. About 60% of it is available to microbial utilization in less than 5 days. If exposed to solar radiation, however, this DOC becomes less labile. Thus, plastic pollution of marine surface waters likely alters the composition and activity of the base of the marine food webs. It is predicted that plastic waste entering the ocean will increase by a factor of ten within the next decade, resulting in an increase in plastic-derived DOC that might have unaccounted consequences for marine microbes and for the ocean system.

Marine debris from the Oregon Dungeness crab fishery recovered in the Northwestern Hawaiian Islands: identification and oceanic drift paths.

PubMed

Ebbesmeyer, Curtis C; Ingraham, W J; Jones, Jason A; Donohue, Mary J

2012-01-01

Two Dungeness crab trap tags and floats lost off the State of Oregon, USA during the 2006-2007 fishing season were recovered 4years later in the Northwestern Hawaiian Islands (NWHI): on Lisianski Island on July 15, 2010; and on Kure Atoll on December 10, 2010. This is the first documented recovery of marine debris from Oregon fisheries in the NWHI. We simulate the oceanic drift tracks of the derelict fishing gear with the Ocean Surface Current Simulator (OSCURS) model using estimated loss dates in Oregon based on interviews with the crab trap owners and known recovery sites and dates in the NWHI. These data confirm the US Pacific Northwest as a source of marine debris deposited in the NWHI and provide enhanced understanding of the oceanic drift pathways of marine debris in the North Pacific Ocean. Copyright © 2011 Elsevier Ltd. All rights reserved.

Triple-wavelength lidar observations of the linear depolarization ratio of dried marine particles

NASA Astrophysics Data System (ADS)

Haarig, Moritz; Ansmann, Albert; Baars, Holger; Engelmann, Ronny; Althausen, Dietrich; Bohlmann, Stephanie; Gasteiger, Josef; Farrell, David

2018-04-01

For aerosol typing with lidar, sea salt particles are usually assumed to be spherical with a consequently low depolarization ratio. Evidence of dried marine particles at the top of the humid marine aerosol layer with a depolarization ratio up to 0.1 has been found at predominately maritime locations on Barbados and in the Southern Atlantic. The depolarization ratio for these probably cubic sea salt particles has been measured at three wavelengths (355, 532 and 1064 nm) simultaneously for the first time and compared to model simulations.

Spring bloom onset in the Nordic Seas

NASA Astrophysics Data System (ADS)

Mignot, Alexandre; Ferrari, Raffaele; Mork, Kjell Arne

2016-06-01

The North Atlantic spring bloom is a massive annual growth event of marine phytoplankton, tiny free-floating algae that form the base of the ocean's food web and generates a large fraction of the global primary production of organic matter. The conditions that trigger the onset of the spring bloom in the Nordic Seas, at the northern edge of the North Atlantic, are studied using in situ data from six bio-optical floats released north of the Arctic Circle. It is often assumed that spring blooms start as soon as phytoplankton cells daily irradiance is sufficiently abundant that division rates exceed losses. The bio-optical float data instead suggest the tantalizing hypothesis that Nordic Seas blooms start when the photoperiod, the number of daily light hours experienced by phytoplankton, exceeds a critical value, independently of division rates. The photoperiod trigger may have developed at high latitudes where photosynthesis is impossible during polar nights and phytoplankton enters into a dormant stage in winter. While the first accumulation of biomass recorded by the bio-optical floats is consistent with the photoperiod hypothesis, it is possible that some biomass accumulation started before the critical photoperiod but at levels too low to be detected by the fluorometers. More precise observations are needed to test the photoperiod hypothesis.

Marine pollution: an overview

NASA Astrophysics Data System (ADS)

Valentukevičienė, Marina; Brannvall, Evelina

2008-01-01

This overview of marine pollution follows the methodology as proposed below. Firstly, well-known databases (Science Direct, GeoRef, SpringerLINK, etc.) on technological research were studied. All collected references were divided into 27 sections following the key words associated with marine pollution, oil spills, alien species migration, etc. The most commercially promising research and development (R & D) activities seem to be market-oriented sections: detection of oil spills at sea, containment and recovery of floating oil at sea, detection of oil spills on land, disposal of oil and debris on land, alien species migration prevention from ballast water and underwater hull cleaning in water, NOx and SOx emissions, pollutions from ship-building and repair, and biogeochemical modelling. Great market demands for commercially patented innovations are very attractive for initiating new R & D projects.

Study of the effects of oil on marine turtles. Volume 3. Appendices. Final report, 30 September 1983-1 October 1985

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

Vargo, S.; Lutz, P.; Odell, D.

1986-09-15

The objective of the study was to determine the effects of oil on marine turtles. An experimental program was carried out on 3-20 month old loggerhead and 3-16 month old green turtles to determine behavioral and physiological effects of oil using South Louisiana Crude Oil (SLCO) preweathered for 48 hrs. The behavioral experiments indicated that both species of marine turtles had a limited ability to avoid oil slicks, but experiments to determine avoidance/attraction to floating tar balls were inconclusive. The physiological experiments showed that the respiration, skin, some aspects of blood chemistry and composition, and salt gland function of 15-18more » month old loggerhead sea turtles were significantly affected.« less

Study of the effects of oil on marine turtles. Volume 1. Executive summary. Final report, 30 September 1983-1 October 1985

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

Vargo, S.; Lutz, P.; Odell, D.

1986-09-15

The objective of the study was to determine the effects of oil on marine turtles. An experimental program was carried out on 3-20 month old loggerhead and 3-16 month old green turtles to determine behavioral and physiological effects of oil using South Louisiana Crude Oil (SLCO) preweathered for 48 hrs. The behavioral experiments indicated that both species of marine turtles had a limited ability to avoid oil slicks, but experiments to determine avoidance/attraction to floating tar balls were inconclusive. The physiological experiments showed that the respiration, skin, some aspects of blood chemistry and composition, and salt gland function of 15-18more » month old loggerhead sea turtles were significantly affected.« less

Quantification and Analysis of Icebergs in a Tidewater Glacier Fjord Using an Object-Based Approach.

PubMed

McNabb, Robert W; Womble, Jamie N; Prakash, Anupma; Gens, Rudiger; Haselwimmer, Christian E

2016-01-01

Tidewater glaciers are glaciers that terminate in, and calve icebergs into, the ocean. In addition to the influence that tidewater glaciers have on physical and chemical oceanography, floating icebergs serve as habitat for marine animals such as harbor seals (Phoca vitulina richardii). The availability and spatial distribution of glacier ice in the fjords is likely a key environmental variable that influences the abundance and distribution of selected marine mammals; however, the amount of ice and the fine-scale characteristics of ice in fjords have not been systematically quantified. Given the predicted changes in glacier habitat, there is a need for the development of methods that could be broadly applied to quantify changes in available ice habitat in tidewater glacier fjords. We present a case study to describe a novel method that uses object-based image analysis (OBIA) to classify floating glacier ice in a tidewater glacier fjord from high-resolution aerial digital imagery. Our objectives were to (i) develop workflows and rule sets to classify high spatial resolution airborne imagery of floating glacier ice; (ii) quantify the amount and fine-scale characteristics of floating glacier ice; (iii) and develop processes for automating the object-based analysis of floating glacier ice for large number of images from a representative survey day during June 2007 in Johns Hopkins Inlet (JHI), a tidewater glacier fjord in Glacier Bay National Park, southeastern Alaska. On 18 June 2007, JHI was comprised of brash ice ([Formula: see text] = 45.2%, SD = 41.5%), water ([Formula: see text] = 52.7%, SD = 42.3%), and icebergs ([Formula: see text] = 2.1%, SD = 1.4%). Average iceberg size per scene was 5.7 m2 (SD = 2.6 m2). We estimate the total area (± uncertainty) of iceberg habitat in the fjord to be 455,400 ± 123,000 m2. The method works well for classifying icebergs across scenes (classification accuracy of 75.6%); the largest classification errors occur in areas with densely-packed ice, low contrast between neighboring ice cover, or dark or sediment-covered ice, where icebergs may be misclassified as brash ice about 20% of the time. OBIA is a powerful image classification tool, and the method we present could be adapted and applied to other ice habitats, such as sea ice, to assess changes in ice characteristics and availability.

Quantification and Analysis of Icebergs in a Tidewater Glacier Fjord Using an Object-Based Approach

PubMed Central

McNabb, Robert W.; Womble, Jamie N.; Prakash, Anupma; Gens, Rudiger; Haselwimmer, Christian E.

2016-01-01

Tidewater glaciers are glaciers that terminate in, and calve icebergs into, the ocean. In addition to the influence that tidewater glaciers have on physical and chemical oceanography, floating icebergs serve as habitat for marine animals such as harbor seals (Phoca vitulina richardii). The availability and spatial distribution of glacier ice in the fjords is likely a key environmental variable that influences the abundance and distribution of selected marine mammals; however, the amount of ice and the fine-scale characteristics of ice in fjords have not been systematically quantified. Given the predicted changes in glacier habitat, there is a need for the development of methods that could be broadly applied to quantify changes in available ice habitat in tidewater glacier fjords. We present a case study to describe a novel method that uses object-based image analysis (OBIA) to classify floating glacier ice in a tidewater glacier fjord from high-resolution aerial digital imagery. Our objectives were to (i) develop workflows and rule sets to classify high spatial resolution airborne imagery of floating glacier ice; (ii) quantify the amount and fine-scale characteristics of floating glacier ice; (iii) and develop processes for automating the object-based analysis of floating glacier ice for large number of images from a representative survey day during June 2007 in Johns Hopkins Inlet (JHI), a tidewater glacier fjord in Glacier Bay National Park, southeastern Alaska. On 18 June 2007, JHI was comprised of brash ice (x¯ = 45.2%, SD = 41.5%), water (x¯ = 52.7%, SD = 42.3%), and icebergs (x¯ = 2.1%, SD = 1.4%). Average iceberg size per scene was 5.7 m2 (SD = 2.6 m2). We estimate the total area (± uncertainty) of iceberg habitat in the fjord to be 455,400 ± 123,000 m2. The method works well for classifying icebergs across scenes (classification accuracy of 75.6%); the largest classification errors occur in areas with densely-packed ice, low contrast between neighboring ice cover, or dark or sediment-covered ice, where icebergs may be misclassified as brash ice about 20% of the time. OBIA is a powerful image classification tool, and the method we present could be adapted and applied to other ice habitats, such as sea ice, to assess changes in ice characteristics and availability. PMID:27828967

Underwater Sound Scattering by Marine Organisms. A Review,

DTIC Science & Technology

1979-08-01

play the dominant scattering role in different seasons . 2.2 Correlation of Acoustic Reverberation Measurements with the Geographic Distribution of...to scattering beneath a floating ice station on the Beaufort Sea. Plankton net hauls indicated that accumulations of the thecostomatous pteropod ...and in the combined upper layer at night. Of these, the siphonophore, Ablyopsis tetragona, pteropod Cymbulia sp.,euphausiids, Thysanopoda sp. and

Survey of Experience Using Reinforced Concrete in Floating Marine Structures.

DTIC Science & Technology

1983-01-01

organizations involved in materials research and testing . The second largest group consists of those involved in design, consulting, and construction...This distribution is consistent with the open literature where the majority of articles are concerned with materials research, testing , and design. Only...example, organizations involved in materials research, design, testing , and certification were visited in the Netherlands, France, Norway, Scotland, and

A global inventory of small floating plastic debris

NASA Astrophysics Data System (ADS)

van Sebille, Erik; Wilcox, Chris; Lebreton, Laurent; Maximenko, Nikolai; Hardesty, Britta Denise; van Franeker, Jan A.; Eriksen, Marcus; Siegel, David; Galgani, Francois; Lavender Law, Kara

2015-12-01

Microplastic debris floating at the ocean surface can harm marine life. Understanding the severity of this harm requires knowledge of plastic abundance and distributions. Dozens of expeditions measuring microplastics have been carried out since the 1970s, but they have primarily focused on the North Atlantic and North Pacific accumulation zones, with much sparser coverage elsewhere. Here, we use the largest dataset of microplastic measurements assembled to date to assess the confidence we can have in global estimates of microplastic abundance and mass. We use a rigorous statistical framework to standardize a global dataset of plastic marine debris measured using surface-trawling plankton nets and coupled this with three different ocean circulation models to spatially interpolate the observations. Our estimates show that the accumulated number of microplastic particles in 2014 ranges from 15 to 51 trillion particles, weighing between 93 and 236 thousand metric tons, which is only approximately 1% of global plastic waste estimated to enter the ocean in the year 2010. These estimates are larger than previous global estimates, but vary widely because the scarcity of data in most of the world ocean, differences in model formulations, and fundamental knowledge gaps in the sources, transformations and fates of microplastics in the ocean.

Petrology of Mississippian carbonate eolianites and associated facies: Ste. Genevieve Limestone of Indiana

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

Dodd, J.R.; Brown, T.W.; Harris, C.D.

1990-05-01

Descriptions of carbonate eolianites of pre-Pleistocene age are rare. Based largely on sedimentary structures and facies associations, Hunter has recently identified eolian deposits in the middle Mississippian Ste. Genevieve Limestone near Corydon, Indiana. Eolianite grainstones contain a diverse assemblage of allochems, including a variety of skeletal grains, ooids (some broken and abraded), peloids, intraclasts, and abundant quartz silt. Carbonate grains, which rarely exceed 0.5 mm are usually more spherical than grains from associated marine unit. Eolian units contain cross-laminations that sometimes coarsen upward. No evidence for vadose cement was found in the eolianite units; the extensive solution packing suggest thatmore » cementation did not occur until burial to considerable depth. Marine grainstones, which probably formed on shallow shoals or an open platform, are common in the section. They contain a diverse assemblage of skeletal grain types as well as ooids, peloids, and intraclasts; however, one grain type (such as ooids) frequently dominates an individual unit. Detrital quartz grains are rare. Rounding of grains is usually good, but sphericity of skeletal grains which were not originally spherical is low. Fine laminations are uncommon, and no systematic grading is found on a thin-section scale. Grains and fossils in excess of 10 mm are common in the marine unit. Carbonate mud-rich rocks that probably formed in a shallow lagoonal setting also occur in the Ste. Genevieve section as do poorly developed exposure surfaces with pedogenic features.« less

From viscous to elastic sheets: Dynamics of smectic freely floating films

NASA Astrophysics Data System (ADS)

Harth, Kirsten; May, Kathrin; Trittel, Torsten; Stannarius, Ralf

2015-03-01

Oscillations and rupture of bubbles, composed of an inner fluid separated from an outer fluid by a membrane, represent an old but still immensely active field of research. Membrane properties except surface tension are often neglected for simple fluid films (e.g. soap bubbles), whereas they govern the dynamics in systems with more complex membranes (e.g. vesicles). Due to their layered phase structure, smectic liquid crystals can form stable, uniform and easy-to handle fluid films of immense aspect ratios. Recently, freely floating bubbles detached from a support were prepared. We analyze the relaxation from strongly non-spherical shapes and the rupture dynamics of such bubbles using high-speed video recordings. Peculiar dynamics intermediate between those of simple viscous fluid films and an elastic response emerge: Oscillations, slowed relaxation and even the formation of wrinkles and extrusions. We characterize these phenomena and propose explanations. We acknowledge funding by the German Aerospace Center DLR within Project OASIS-CO and German Science Foundation Project STA 425-28.

The Euro-Argo education web site: using Argo data to teach data analysis and marine science

NASA Astrophysics Data System (ADS)

Byfield, Valborg; Scheurle, Carolyn; Gould, John; Macama, Emina; King, Brian

2013-04-01

The Euro-Argo education website (www.euroargo-edu.org) aims to make Argo and its data accessible to a non-specialist audience. The site is centred on a selection of floats, which have been chosen because of the insight they provide into key oceanographic processes, the physical and biogeochemical characteristics of different ocean regions around the world, and the role of the ocean in the global climate system. The float selection is a vehicle for teaching data analysis skills, linking these to current topics in the ocean and climate sciences. Each float in the selection has its own page, which provides access to the float data, data plots, background information on the ocean region in which the float can be found, and questions to guide data interpretation. Hidden 'model answers' allow users to check their understanding by comparing their own answers to those provided. The interactive component of the site also includes a series of quizzes, designed to teach data interpretation skills. These start at a basic level and take the students step by step through the most common ways to plot oceanographic data in space and time. More general background information covers the main aspects of the Argo programme, its history and applications, and basic technical information about the floats and sensors. 'World Tour' pages linked to the float selection provide information about the main ocean regions and link information from the Argo programme to oceanographic information from other sources such as satellite observations. The site is primarily aimed at young people between 11 and 18 years of age. However experience from using selected material from the site during science open days shows that children as young as 8-9 and adults of all ages also enjoy the challenge of using and interpreting the Argo data in different contexts.

Marine and Other Aquatic Dermatoses

PubMed Central

Sridhar, Surg Capt. Jandhyala; Deo, Surg Cdr. Rajeev

2017-01-01

Occupational and recreational aquatic activity predisposes our population to a wide variety of dermatoses. Sunburn, urticaria, jellyfish stings, and contact dermatitis to rubber equipment are common allergies that are encountered in the aquatic environment. Among the infections, tinea versicolor, intertrigo, and verruca vulgaris are widespread. Swimmer's itch may occur due to skin penetration by schistosome cercariae, while free-floating nematocysts of marine coelenterates may precipitate seabather's eruption. “Suit squeeze” due to cutaneous barotrauma and lymphoedematous peau d’orange due to decompression are rare, described entities. This review serves as a ready reckoner for Indian dermatologists and medical practitioners to identify and manage these conditions. PMID:28216728

Understanding sources, sinks, and transport of marine debris

NASA Astrophysics Data System (ADS)

Law, Kara Lavender; Maximenko, Nikolai

2011-07-01

Fifth International Marine Debris Conference: Hydrodynamics of Marine Debris; Honolulu, Hawaii, 20 March 2011; Ocean pollution in the form of marine debris, especially plastic debris, has received increasing public and media attention in recent years through striking but frequently inaccurate descriptions of “garbage patches.” Marine debris is composed of all manufactured materials, including glass, metal, paper, fibers, and plastic, that have been deliberately dumped or that accidentally entered the marine environment. Marine debris is most visible on beaches, but it has been observed in all oceans and in such remote locations as on the deep seabed and floating in the middle of subtropical ocean gyres. While many initiatives have been developed to solve this pollution problem through prevention and cleanup efforts, there is relatively little scientific information available to assess the current status of the problem or to provide metrics to gauge the success of remediation measures. With this in mind, a full-day workshop entitled “Hydrodynamics of Marine Debris” was convened at the Fifth International Marine Debris Conference in Hawaii, bringing together observational scientists and oceanographic modelers to outline the steps necessary to quantify the major sources and sinks of marine debris and the pathways between them. The ultimate goal in integrating the two approaches of study is to quantify the basinscale and global inventory of marine debris by closing the associated mass budgets.

Plastic Pollution in the World's Oceans: More than 5 Trillion Plastic Pieces Weighing over 250,000 Tons Afloat at Sea.

PubMed

Eriksen, Marcus; Lebreton, Laurent C M; Carson, Henry S; Thiel, Martin; Moore, Charles J; Borerro, Jose C; Galgani, Francois; Ryan, Peter G; Reisser, Julia

2014-01-01

Plastic pollution is ubiquitous throughout the marine environment, yet estimates of the global abundance and weight of floating plastics have lacked data, particularly from the Southern Hemisphere and remote regions. Here we report an estimate of the total number of plastic particles and their weight floating in the world's oceans from 24 expeditions (2007-2013) across all five sub-tropical gyres, costal Australia, Bay of Bengal and the Mediterranean Sea conducting surface net tows (N = 680) and visual survey transects of large plastic debris (N = 891). Using an oceanographic model of floating debris dispersal calibrated by our data, and correcting for wind-driven vertical mixing, we estimate a minimum of 5.25 trillion particles weighing 268,940 tons. When comparing between four size classes, two microplastic <4.75 mm and meso- and macroplastic >4.75 mm, a tremendous loss of microplastics is observed from the sea surface compared to expected rates of fragmentation, suggesting there are mechanisms at play that remove <4.75 mm plastic particles from the ocean surface.

Plastic Pollution in the World's Oceans: More than 5 Trillion Plastic Pieces Weighing over 250,000 Tons Afloat at Sea

PubMed Central

Eriksen, Marcus; Lebreton, Laurent C. M.; Carson, Henry S.; Thiel, Martin; Moore, Charles J.; Borerro, Jose C.; Galgani, Francois; Ryan, Peter G.; Reisser, Julia

2014-01-01

Plastic pollution is ubiquitous throughout the marine environment, yet estimates of the global abundance and weight of floating plastics have lacked data, particularly from the Southern Hemisphere and remote regions. Here we report an estimate of the total number of plastic particles and their weight floating in the world's oceans from 24 expeditions (2007–2013) across all five sub-tropical gyres, costal Australia, Bay of Bengal and the Mediterranean Sea conducting surface net tows (N = 680) and visual survey transects of large plastic debris (N = 891). Using an oceanographic model of floating debris dispersal calibrated by our data, and correcting for wind-driven vertical mixing, we estimate a minimum of 5.25 trillion particles weighing 268,940 tons. When comparing between four size classes, two microplastic <4.75 mm and meso- and macroplastic >4.75 mm, a tremendous loss of microplastics is observed from the sea surface compared to expected rates of fragmentation, suggesting there are mechanisms at play that remove <4.75 mm plastic particles from the ocean surface. PMID:25494041

Floating macro-litter along the Mediterranean French coast: Composition, density, distribution and overlap with cetacean range.

PubMed

Di-Méglio, Nathalie; Campana, Ilaria

2017-05-15

This study investigated the composition, density and distribution of floating macro-litter along the Liguro-Provençal basin with respect to cetaceans presence. Survey transects were performed in summer between 2006 and 2015 from sailing vessels with simultaneous cetaceans observations. During 5171km travelled, 1993 floating items were recorded, widespread in the whole study area. Plastics was the predominant category, with bags/packaging always representing >45% of total items. Overall mean density (14.98 items/km 2 ) was stable with significant increase reported only in 2010-2011; monthly analysis showed lower litter densities in July-September, suggesting possible seasonal patterns. Kernel density estimation for plastics revealed ubiquitous distribution rather than high accumulation areas, mainly due to the circulation dynamics of this area. The presence range of cetaceans (259 sightings, 6 species) corresponded by ~50% with plastic distribution, indicating high potential of interaction, especially in the eastern part of the area, but effective risks for marine species might be underrepresented. Copyright © 2017 Elsevier Ltd. All rights reserved.

Nuclear Security for Floating Nuclear Power Plants

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

Skiba, James M.; Scherer, Carolynn P.

2015-10-13

Recently there has been a lot of interest in small modular reactors. A specific type of these small modular reactors (SMR,) are marine based power plants called floating nuclear power plants (FNPP). These FNPPs are typically built by countries with extensive knowledge of nuclear energy, such as Russia, France, China and the US. These FNPPs are built in one country and then sent to countries in need of power and/or seawater desalination. Fifteen countries have expressed interest in acquiring such power stations. Some designs for such power stations are briefly summarized. Several different avenues for cooperation in FNPP technology aremore » proposed, including IAEA nuclear security (i.e. safeguards), multilateral or bilateral agreements, and working with Russian design that incorporates nuclear safeguards for IAEA inspections in non-nuclear weapons states« less

Modeling the drift of plastics in the Adriatic Basin

NASA Astrophysics Data System (ADS)

Liubartseva, Svitlana; Coppini, Giovanni; Lecci, Rita; Creti, Sergio

2016-04-01

Recently, plastic pollution at sea has become widely recognized as an acute environmental problem. Distribution of plastics in the marine environment is controlled by (1) locations and time-varying intensity of inputs; (2) the dynamics of the upper mixed layer of the ocean, where the majority of plastics float; and (3) the sinks of plastics. In the present work, we calculate the plastic concentrations at the sea surface and fluxes onto the coastline (2009-2015) that originated from terrestrial and maritime inputs. We construct a Markov chain model based on coupling the MEDSLIK-II model (De Dominicis et al., 2013) with the daily Adriatic Forecasting System (AFS) ocean currents simulations (1/45° horizontal resolution) (Guarneri et al., 2010) and ECMWF surface wind analyses (0.25° horizontal and 6-h temporal resolutions). We assume that the coastline is the main sink of plastics in the Adriatic Sea (Liubartseva et al., 2015). Our calculations have shown that the mean particle half-life in the basin approximately equals 43.7 days, which allows us to define the Adriatic Sea as a highly dissipative system with respect to floating plastics. On long-term time-mean scales, the most polluted sea surface area (more than 10 g/km2 floating plastics) is represented by an elongated band shifted to the Italian coastline and narrowed from northwest to southeast. That corresponds to the spatial distributions of plastic inputs, and indicates a tight connection with patterns of the general Adriatic circulation, including the Western Adriatic Coastal Current and the South Adriatic gyre. On seasonal time-mean scales, we indicate the winter plastics' expansion into the basin's interior, spring trapping in the northern Adriatic, summer cleansing the middle and southern Adriatic and autumn spreading into the southeastern Adriatic. Distinctive coastal "hot spot" is found on the Po Delta coastline that receives a plastic flux of 70 kg/(kmṡday). Complex source-receptor relationships among the Adriatic subregions are quantified in terms of impact matrices. The results obtained can be used to monitor the floating debris, plan cleanups, and make policy-relevant decisions. The methodology could be further improved by including consideration of plastic particles sinking, breaking into microplastics, and being ingested by biota. Furthermore, we believe that in the future, higher resolution current data will enhance the Lagrangian representation of floating plastic transport. This work has been supported by the DeFishGear (Derelict Fishing Gear Management System in the Adriatic Region (http://www.defishgear.net/) IPA Adriatic strategic project 1° str/00010 implemented with co-funding by the European Union, Instrument for Pre-Accession Assistance (IPA). References De Dominicis, M., Pinardi, N., Zodiatis, G., Lardner, R., 2013. MEDSLIK-II, a Lagrangian marine surface oil spill model for short term forecasting - Part 1: Theory. Geosci. Model Dev. 6, 1851-1869. Guarnieri, A., Oddo, P., Pastore, M., Pinardi, N., 2010. The Adriatic Basin Forecasting System new model and system development, in: Coastal to Global Operational Oceanography: Achievements and Challenges, 184-190. Liubartseva, S., Coppini, G., Lecci, R., Creti, S., Regional approach to modeling the transport of floating plastic debris in the Adriatic Sea. Marine Pollution Bulletin (2015) http://dx.doi.org/10.1016/j.marpolbul.2015.12.031.

A Method for Measuring Fishing Effort by Small-Scale Fish Aggregating Device (FAD) Fishers from the Commonwealth of Dominica

ERIC Educational Resources Information Center

Alvard, Michael; McGaffey, Ethan; Carlson, David

2015-01-01

We used global positioning system (GPS) technology and tracking analysis to measure fishing effort by marine, small-scale, fish aggregating device (FAD) fishers of the Commonwealth of Dominica. FADs are human-made structures designed to float on the surface of the water and attract fish. They are also prone to common pool resource problems. To…

The Petermann Glacier Experiment, NW Greenland

NASA Astrophysics Data System (ADS)

Mix, A. C.; Jakobsson, M.; Andrews, J. T.; Jennings, A. E.; Mayer, L. A.; Marcott, S. A.; Muenchow, A.; Stoner, J. S.; Andresen, C. S.; Nicholls, K. W.; Anderson, S. T.; Brook, E.; Ceperley, E. G.; Cheseby, M.; Clark, J.; Dalerum, F.; Dyke, L. M.; Einarsson, D.; Eriksson, B.; Frojd, C.; Glueder, A.; Hedman, U.; Heirman, K.; Heuzé, C.; Hogan, K.; Holden, R.; Holm, C.; Jerram, K.; Krutzfeldt, J.; Nicolas, L.; Par, L.; Lomac-MacNair, K.; Madlener, S.; McKay, J. L.; Meijer, T.; Meiton, A.; Brian, M.; Mohammed, R.; Molin, M.; Moser, C.; Normark, E.; Padman, J.; Pecnerova, P.; Reilly, B.; Reusche, M.; Ross, A.; Stranne, C.; Trinhammer, P.; Walczak, M. H.; Walczak, P.; Washam, P.; Karasti, M.; Anker, P.

2016-12-01

The Petermann Glacier Experiment is a comprehensive study on land, ocean, and ice in Northwest Greenland, staged from Swedish Icebreaker Oden in 2015 as a collaboration between the US, Sweden, UK, and Denmark. This talk introduces the strategic goals of the experiment and connects the various scientific results. Petermann Glacier drains a significant marine-based sector of the northern Greenland Ice Sheet and terminates in a floating ice tongue, one of the largest remaining systems of its kind in the northern hemisphere. Records of the modern state of Petermann Glacier and its past variations are of interest to understand the sensitivity of marine terminating outlet glaciers to change, and to constrain the rates and extent of changes that have actually occurred. With this case study we are learning the rules of large scale dynamics that cannot be understood from modern observations alone. Although past behavior is not an simple analog for the future, and no single system captures all possible behaviors, insights from these case studies can be applied through models to better project how similar systems may change in the future. The Petermann Expedition developed the first comprehensive bathymetric maps of the region, drilled through the floating ice tongue to obtain sub-shelf sediment cores near the grounding line and to monitor sub-ice conditions, recovered a broad array of sediment cores documenting changing oceanic conditions in Petermann Fjord, Hall Basin, and Nares Strait, measured watercolumn properties to trace subsurface watermasses that bring heat from the Arctic Ocean into deep Petermann Fjord to melt the base of the floating ice tongue, developed a detailed record of relative sealevel change on land to constrain past ice loads, and recovered pristine boulders for cosmogenic exposure dating of areal ice retreat on land. Together, these studies are shedding new light on the dynamics of past glaciation in Northwest Greenland, and contributing to fundamental understanding of large marine-terminating outlet glacier systems, which are threatened by global warming and poised to contribute to global sealevel rise in the future. Further information in the Petermann Glacier Experiment is available at https://petermannsglacialhistory.wordpress.com

A 70-year record of outlet glacier retreat in northern Greenland

NASA Astrophysics Data System (ADS)

Hill, Emily; Carr, Rachel; Stokes, Chris; Gudmundsson, Hilmar

2017-04-01

Over the past two decades, the Greenland Ice Sheet (GrIS) has undergone accelerated mass loss increasing its contribution to sea level rise. This is partly attributed to increased mass loss from dynamic marine-terminating outlet glaciers. Despite marine-terminating outlet glaciers in northern Greenland draining 40% of the ice sheet by area, they are comparatively less well-studied than other regions of the ice sheet (e.g. central west or south-east). This region could be susceptible to marine-ice sheet instability due to large proportions of the bedrock rested below sea level and is also unique in the presence of large floating ice tongues. Here, we use a range of satellite imagery sources, accompanied by historical maps, to examine multi-decadal front position changes at 21 outlet glaciers in northern Greenland between 1948 and 2016. We accompany these terminus changes, with annual records of ice velocity, climate-ocean forcing data, and glacier-specific factors (e.g. fjord-width and basal topography) to understand the dominant forcing on glacier dynamics in the region. Over the last 70 years, there has been a clear pattern of glacier retreat in northern Greenland. This is particularly notable during the last two decades, where 62% of our study glaciers showed accelerated retreat. This was most notable at Humboldt, Tracy, Hagen Brae, C. H. Ostenfeld and Petermann Glaciers, and in the case of the latter three glaciers, this involved substantial retreat of their floating ice tongues (> 10 km). Alongside retreat, several study glaciers underwent simultaneous velocity increases. However, the collapse of floating ice tongues did not always result in increased velocity. Similar to other regions of the ice sheet, recent glacier retreat in the northern regions of the Greenland Ice Sheet could be linked to climatic-oceanic forcing, but at this stage this remains largely unknown. This response to external forcing is further complicated by the presence of glacier-surging recorded at several of our study glaciers. As northern Greenland is predicted to undergo greater warming due to Arctic amplification during the 21st century, we conclude that the region could become an increasingly important source of mass loss.

Study of the effects of oil on marine turtles. Volume 2. Technical report. Final report, 30 September 1983-1 October 1985

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

Vargo, S.; Lutz, P.; Odell, D.

1986-09-15

The objective of the study was to determine the effects of oil on marine turtles. An experimental program was carried out on 3-20 month old loggerhead and 3-16 month old green turtles to determine behavioral and physiological effects of oil using South Louisiana Crude Oil (SLCO) preweathered for 48 hrs. The behavioral experiments indicated that both species of marine turtles had a limited ability to avoid oil slicks, but experiments to determine avoidance/attraction to floating tar balls were inconclusive. The physiological experiments showed that the respiration, skin, some aspects of blood chemistry and composition, and salt gland function of 15-18more » month old loggerhead sea turtles were significantly affected. Spills in the vicinity of nesting beaches are of special concern.« less

Morphological description and phylogeny of Ceratomyxa scorpaeni n. sp. (Myxosporea: Ceratomyxidae) infecting the gallbladder of Scorpaena porcus (L.) (Scorpaeniformes: Scorpaenidae) from the bay of Bizerte in Tunisia.

PubMed

Garbouj, Myriam; Rangel, Luís F; Castro, Ricardo; Hmissi, Jihene; Santos, Maria J; Bahri, Sihem

2016-12-01

A new marine myxosporean species Ceratomyxa scorpaeni n. sp. is described using morphological characteristics and small subunit ribosomal DNA (rDNA) sequence data. The parasite was found infecting the gallbladder of Scorpaena porcus Linnaeus, 1758 collected from the Bay of Bizerte. Mature plasmodia were disporous free floating in the bile. Spores were transversely elongated and crescent-shaped with unequal shell valves and measured 7.6 ± 0.2 (7.2-8.0) μm in length and 32.8 ± 0.3 (21.6-44.0) μm in thickness. Two sub-spherical polar capsules equal in size, situated at the same level and measured 3.0 ± 0.2 (3.0-3.2) μm in length and 2.4 ± 0.3 (2.3-3.3) μm in width. The infection with C. scorpaeni n. sp. was prevalent throughout the year with a maximum prevalence of infection during spring and summer. Molecular analysis of the SSU rRNA gene confirmed the parasite as a new member of the genus Ceratomyxa and showed close relationship with the species of Ceratomyxa infecting the gallbladders of Sparidae from the Mediterranean Sea. This is the first report of Ceratomyxa species from the gallbladder of S. porcus in Tunisian coastal waters.

Concept for a hyperspectral remote sensing algorithm for floating marine macro plastics.

PubMed

Goddijn-Murphy, Lonneke; Peters, Steef; van Sebille, Erik; James, Neil A; Gibb, Stuart

2018-01-01

There is growing global concern over the chemical, biological and ecological impact of plastics in the ocean. Remote sensing has the potential to provide long-term, global monitoring but for marine plastics it is still in its early stages. Some progress has been made in hyperspectral remote sensing of marine macroplastics in the visible (VIS) to short wave infrared (SWIR) spectrum. We present a reflectance model of sunlight interacting with a sea surface littered with macro plastics, based on geometrical optics and the spectral signatures of plastic and seawater. This is a first step towards the development of a remote sensing algorithm for marine plastic using light reflectance measurements in air. Our model takes the colour, transparency, reflectivity and shape of plastic litter into account. This concept model can aid the design of laboratory, field and Earth observation measurements in the VIS-SWIR spectrum and explain the results. Copyright © 2017 Elsevier Ltd. All rights reserved.

Modelling accumulation of marine plastics in the coastal zone; what are the dominant physical processes?

NASA Astrophysics Data System (ADS)

Critchell, Kay; Lambrechts, Jonathan

2016-03-01

Anthropogenic marine debris, mainly of plastic origin, is accumulating in estuarine and coastal environments around the world causing damage to fauna, flora and habitats. Plastics also have the potential to accumulate in the food web, as well as causing economic losses to tourism and sea-going industries. If we are to manage this increasing threat, we must first understand where debris is accumulating and why these locations are different to others that do not accumulate large amounts of marine debris. This paper demonstrates an advection-diffusion model that includes beaching, settling, resuspension/re-floating, degradation and topographic effects on the wind in nearshore waters to quantify the relative importance of these physical processes governing plastic debris accumulation. The aim of this paper is to prioritise research that will improve modelling outputs in the future. We have found that the physical characteristic of the source location has by far the largest effect on the fate of the debris. The diffusivity, used to parameterise the sub-grid scale movements, and the relationship between debris resuspension/re-floating from beaches and the wind shadow created by high islands also has a dramatic impact on the modelling results. The rate of degradation of macroplastics into microplastics also have a large influence in the result of the modelling. The other processes presented (settling, wind drift velocity) also help determine the fate of debris, but to a lesser degree. These findings may help prioritise research on physical processes that affect plastic accumulation, leading to more accurate modelling, and subsequently management in the future.

Population assessment of tropical tuna based on their associative behavior around floating objects.

PubMed

Capello, M; Deneubourg, J L; Robert, M; Holland, K N; Schaefer, K M; Dagorn, L

2016-11-03

Estimating the abundance of pelagic fish species is a challenging task, due to their vast and remote habitat. Despite the development of satellite, archival and acoustic tagging techniques that allow the tracking of marine animals in their natural environments, these technologies have so far been underutilized in developing abundance estimations. We developed a new method for estimating the abundance of tropical tuna that employs these technologies and exploits the aggregative behavior of tuna around floating objects (FADs). We provided estimates of abundance indices based on a simulated set of tagged fish and studied the sensitivity of our method to different association dynamics, FAD numbers, population sizes and heterogeneities of the FAD-array. Taking the case study of yellowfin tuna (Thunnus albacares) acoustically-tagged in Hawaii, we implemented our approach on field data and derived for the first time the ratio between the associated and the total population. With more extensive and long-term monitoring of FAD-associated tunas and good estimates of the numbers of fish at FADs, our method could provide fisheries-independent estimates of populations of tropical tuna. The same approach can be applied to obtain population assessments for any marine and terrestrial species that display associative behavior and from which behavioral data have been acquired using acoustic, archival or satellite tags.

Spatial and temporal patterns of stranded intertidal marine debris: is there a picture of global change?

PubMed

Browne, Mark Anthony; Chapman, M Gee; Thompson, Richard C; Amaral Zettler, Linda A; Jambeck, Jenna; Mallos, Nicholas J

2015-06-16

Floating and stranded marine debris is widespread. Increasing sea levels and altered rainfall, solar radiation, wind speed, waves, and oceanic currents associated with climatic change are likely to transfer more debris from coastal cities into marine and coastal habitats. Marine debris causes economic and ecological impacts, but understanding the scope of these requires quantitative information on spatial patterns and trends in the amounts and types of debris at a global scale. There are very few large-scale programs to measure debris, but many peer-reviewed and published scientific studies of marine debris describe local patterns. Unfortunately, methods of defining debris, sampling, and interpreting patterns in space or time vary considerably among studies, yet if data could be synthesized across studies, a global picture of the problem may be avaliable. We analyzed 104 published scientific papers on marine debris in order to determine how to evaluate this. Although many studies were well designed to answer specific questions, definitions of what constitutes marine debris, the methods used to measure, and the scale of the scope of the studies means that no general picture can emerge from this wealth of data. These problems are detailed to guide future studies and guidelines provided to enable the collection of more comparable data to better manage this growing problem.

Impacts of Modification of Alloying Method on Inclusion Evolution in RH Refining of Silicon Steel.

PubMed

Li, Fangjie; Li, Huigai; Zheng, Shaobo; You, Jinglin; Han, Ke; Zhai, Qijie

2017-10-19

This study explores the effect of introducing additional alloy elements not only in a different order but also at different stages of the Ruhrstahl-Heraeus (RH) process of low-carbon silicon steel production. A more economical method, described as "pre-alloying", has been introduced. The evolution of MnO-FeO inclusions produced by pre-alloying was investigated. Results show that spherical 3FeO·MnO inclusions form first, then shelled FeO·zMnO (z = 0.7-4) inclusions nucleate on the surface of pre-existing 3FeO·MnO. Spherical FeO·zMnO (z = 3-5) is further evolved from shelled 3FeO·MnO by diffusion. Because these MnO-FeO inclusions float up into the slag before degassing, the pre-alloying process does not affect the quality of the melt in the end. Both carbon content and inclusion size conform to industry standards.

Impacts of Modification of Alloying Method on Inclusion Evolution in RH Refining of Silicon Steel

PubMed Central

Li, Huigai; Zheng, Shaobo; You, Jinglin; Han, Ke; Zhai, Qijie

2017-01-01

This study explores the effect of introducing additional alloy elements not only in a different order but also at different stages of the Ruhrstahl-Heraeus (RH) process of low-carbon silicon steel production. A more economical method, described as “pre-alloying”, has been introduced. The evolution of MnO-FeO inclusions produced by pre-alloying was investigated. Results show that spherical 3FeO·MnO inclusions form first, then shelled FeO·zMnO (z = 0.7–4) inclusions nucleate on the surface of pre-existing 3FeO·MnO. Spherical FeO·zMnO (z = 3–5) is further evolved from shelled 3FeO·MnO by diffusion. Because these MnO-FeO inclusions float up into the slag before degassing, the pre-alloying process does not affect the quality of the melt in the end. Both carbon content and inclusion size conform to industry standards. PMID:29048379

Libpsht - algorithms for efficient spherical harmonic transforms

NASA Astrophysics Data System (ADS)

Reinecke, M.

2011-02-01

Libpsht (or "library for performant spherical harmonic transforms") is a collection of algorithms for efficient conversion between spatial-domain and spectral-domain representations of data defined on the sphere. The package supports both transforms of scalars and spin-1 and spin-2 quantities, and can be used for a wide range of pixelisations (including HEALPix, GLESP, and ECP). It will take advantage of hardware features such as multiple processor cores and floating-point vector operations, if available. Even without this additional acceleration, the employed algorithms are among the most efficient (in terms of CPU time, as well as memory consumption) currently being used in the astronomical community. The library is written in strictly standard-conforming C90, ensuring portability to many different hard- and software platforms, and allowing straightforward integration with codes written in various programming languages like C, C++, Fortran, Python etc. Libpsht is distributed under the terms of the GNU General Public License (GPL) version 2 and can be downloaded from .

Libpsht: Algorithms for Efficient Spherical Harmonic Transforms

NASA Astrophysics Data System (ADS)

Reinecke, Martin

2010-10-01

Libpsht (or "library for Performing Spherical Harmonic Transforms") is a collection of algorithms for efficient conversion between spatial-domain and spectral-domain representations of data defined on the sphere. The package supports transforms of scalars as well as spin-1 and spin-2 quantities, and can be used for a wide range of pixelisations (including HEALPix, GLESP and ECP). It will take advantage of hardware features like multiple processor cores and floating-point vector operations, if available. Even without this additional acceleration, the employed algorithms are among the most efficient (in terms of CPU time as well as memory consumption) currently being used in the astronomical community. The library is written in strictly standard-conforming C90, ensuring portability to many different hard- and software platforms, and allowing straightforward integration with codes written in various programming languages like C, C++, Fortran, Python etc. Libpsht is distributed under the terms of the GNU General Public License (GPL) version 2. Development on this project has ended; its successor is libsharp (ascl:1402.033).

A Comparative Study of Production of Glass Microspheres by using Thermal Process

NASA Astrophysics Data System (ADS)

Lee, May Yan; Tan, Jully; Heng, Jerry YY; Cheeseman, Christopher

2017-06-01

Microspheres are spherical particles that can be distinguished into two categories; solid or hollow. Microspheres typical ranges from 1 to 200 μm in diameter. Microsphere are made from glass, ceramic, carbon or plastic depending on applications. Solid glass microsphere is manufactured by direct burning of glass powders while hollow glass microspheres is produced by adding blowing agent to glass powder. This paper presented the production of glass microspheres by using the vertical thermal flame (VTF) process. Pre-treated soda lime glass powder with particle sized range from 90 to 125μm was used in this work. The results showed that glass microspheres produced by two passes through the flame have a more spherical shape as compared with the single pass. Under the Scanning Electron Microscope (SEM), it is observed that there is a morphology changed from uneven surface of glass powders to smooth spherical surface particles. Qualitative analysis for density of the pre-burned and burned particles was performed. Burned particles floats in water while pre-burned particles sank indicated the change of density of the particles. Further improvements of the VTF process in terms of the VTF set-up are required to increase the transformation of glass powders to glass microspheres.

Further Studies of the Inhomgeneous Sheath as the Source of Collisionless Resistance in Plasmas in Spherical Geometry*

NASA Astrophysics Data System (ADS)

Walker, D. N.; Fernsler, R. F.; Blackwell, D. D.; Amatucci, W. E.; Messer, S. J.

2006-05-01

In a recently published work1 we use a simpler derivation of collisionless resistance in spherical geometry than previous authors, relying primarily on Gauss' law along with the continuity and cold fluid equations. The accompanying experimental work is based on measurements of the rf impedance characteristics of a small spherical probe immersed in a laboratory plasma. The data taken are from network analyzer measurements of the reflection coefficient obtained when applying a low level rf signal to the probe which is either near floating potential or negatively dc-biased in a low pressure plasma. The reduced density in the sheath alters the plasma impedance which becomes resistive, in spite of collisionless conditions, and hence the characterization of energy absorption as collisionless arises. Consistent with earlier work, the solutions obtained indicate that the plasma resistance is inversely proportional to the plasma density gradient evaluated at the location where the plasma frequency is equal to the applied frequency. Significant energy absorption is predicted and observed at frequencies generally near one-half the plasma frequency. *Work supported by ONR 1 Walker, D.N., R.F. Fernsler, D.D. Blackwell, W.A. Amatucci, S.J. Messer, Phys of Plasmas, To Appear 3/2006

Effect of Trapped Ions on Shielding and Floating Potential of a Dust Grain in a Plasma

NASA Astrophysics Data System (ADS)

Lampe, Martin; Ganguli, Gurudas; Joyce, Glenn; Gavrishchaka, Valeriy

2001-10-01

The problem of electrostatic shielding around a small spherical collector immersed in plasma, and the related problem of electron and ion flow to the collector, date to the origins of plasma physics. Beginning with Mott-Smith and Langmuir (1926), calculations have typically neglected collisions, on the grounds that the mean free path is long compared to shielding length scales, i.e. the Debye length. However, investigators beginning with Bernstein and Rabinowitz (1959) have known that negative-energy trapped ions, created by occasional collisions, might be important. We present an analytic calculation of the density of trapped and untrapped ions, self-consistent with the potential. Under typical conditions for dust grains immersed in a discharge plasma, trapped ions dominate the shielding cloud in steady state, even in the limit of very long mean free path. As a result the shielded potential is different from the results of orbital motion limited theory. Collisions also greatly increase the ion current to the collector, thereby decreasing the floating potential and the grain charge by a factor as large as two to three.

The OMEGA system for marine bioenergy, wastewater treatment, environmental enhancement, and aquaculture

NASA Astrophysics Data System (ADS)

Trent, J. D.

2013-12-01

OMEGA is an acronym for Offshore Membrane Enclosure for Growing Algae. The OMEGA system consists of photobioreactors (PBRs) made of flexible, inexpensive clear plastic tubes attached to floating docks, anchored offshore in naturally or artificially protected bays [1]. The system uses domestic wastewater and CO2 from coastal facilities to provide water, nutrients, and carbon for algae cultivation [2]. The surrounding seawater maintains the temperature inside the PBRs and prevents the cultivated (freshwater) algae from becoming invasive species in the marine environment (i.e., if a PBR module accidentally leaks, the freshwater algae that grow in wastewater cannot survive in the marine environment). The salt gradient between seawater and wastewater is used for forward osmosis (FO) to concentrate nutrients and facilitate algae harvesting [3]. Both the algae and FO clean the wastewater, removing nutrients as well as pharmaceuticals and personal-care products [4]. The offshore infrastructure provides a large surface area for solar-photovoltaic arrays and access to offshore wind or wave generators. The infrastructure can also support shellfish, finfish, or seaweed aquaculture. The economics of the OMEGA system are supported by a combination of biofuels production, wastewater treatment, alternative energy generation, and aquaculture. By using wastewater and operating offshore from coastal cities, OMEGA can be located close to wastewater and CO2 sources and it can avoid competing with agriculture for water, fertilizer, and land [5]. By combining biofuels production with wastewater treatment and aquaculture, the OMEGA system provides both products and services, which increase its economic feasibility. While the offshore location has engineering challenges and concerns about the impact and control of biofouling [6], large OMEGA structure will be floating marine habitats and will create protected 'no-fishing' zones that could increase local biodiversity and fishery productivity. Potential test sites for the next phase of OMEGA (1-hectare integrated system) will be discussed.

An improved understanding of the natural resonances of moonpools contained within floating rigid-bodies: Theory and application to oscillating water column devices

DOE PAGES

Bull, Diana L.

2015-09-23

The fundamental interactions between waves, a floating rigid-body, and a moonpool that is selectively open to atmosphere or enclosed to purposefully induce pressure fluctuations are investigated. The moonpool hydrodynamic characteristics and the hydrodynamic coupling to the rigid-body are derived implicitly through reciprocity relations on an array of field points. By modeling the free surface of the moonpool in this manner, an explicit hydrodynamic coupling term is included in the equations of motion. This coupling results in the migration of the moonpool's natural resonance frequency from the piston frequency to a new frequency when enclosed in a floating rigid-body. Two geometriesmore » that highlight distinct aspects of marine vessels and oscillating water column (OWC) renewable energy devices are analyzed to reveal the coupled natural resonance migration. The power performance of these two OWCs in regular waves is also investigated. The air chamber is enclosed and a three-dimensional, linear, frequency domain performance model that links the rigid-body to the moonpool through a linear resistive control strategy is detailed. Furthermore, an analytic expression for the optimal linear resistive control values in regular waves is presented.« less

An improved understanding of the natural resonances of moonpools contained within floating rigid-bodies: Theory and application to oscillating water column devices

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

Bull, Diana L.

The fundamental interactions between waves, a floating rigid-body, and a moonpool that is selectively open to atmosphere or enclosed to purposefully induce pressure fluctuations are investigated. The moonpool hydrodynamic characteristics and the hydrodynamic coupling to the rigid-body are derived implicitly through reciprocity relations on an array of field points. By modeling the free surface of the moonpool in this manner, an explicit hydrodynamic coupling term is included in the equations of motion. This coupling results in the migration of the moonpool's natural resonance frequency from the piston frequency to a new frequency when enclosed in a floating rigid-body. Two geometriesmore » that highlight distinct aspects of marine vessels and oscillating water column (OWC) renewable energy devices are analyzed to reveal the coupled natural resonance migration. The power performance of these two OWCs in regular waves is also investigated. The air chamber is enclosed and a three-dimensional, linear, frequency domain performance model that links the rigid-body to the moonpool through a linear resistive control strategy is detailed. Furthermore, an analytic expression for the optimal linear resistive control values in regular waves is presented.« less

Storm Water Toxicity Evaluation Conducted at Naval Station San Diego, Naval Submarine Base San Diego, Naval Amphibious Base Coronado, and Naval Air Station North Island

DTIC Science & Technology

2006-05-01

Polycyclic Aromatic Hydrocarbons and Petroleum to Marine Invertebrate Larvae and Juveniles,” Environ. Toxicol. Chem., vol. 16, pp. 2190–2199...aromatic hydrocarbons , polychlorinated biphenyls, and chlorinated pesticides. Seventeen plume mapping surveys, including an on-site floating bioassay...Non-point Source NS&T National Status and Trends PAH Polynuclear Aromatic Hydrocarbon PCB Polychlorinated Biphenyl PMSD Percent

Environmental implications of plastic debris in marine settings—entanglement, ingestion, smothering, hangers-on, hitch-hiking and alien invasions

PubMed Central

Gregory, Murray R.

2009-01-01

Over the past five or six decades, contamination and pollution of the world’s enclosed seas, coastal waters and the wider open oceans by plastics and other synthetic, non-biodegradable materials (generally known as ‘marine debris’) has been an ever-increasing phenomenon. The sources of these polluting materials are both land- and marine-based, their origins may be local or distant, and the environmental consequences are many and varied. The more widely recognized problems are typically associated with entanglement, ingestion, suffocation and general debilitation, and are often related to stranding events and public perception. Among the less frequently recognized and recorded problems are global hazards to shipping, fisheries and other maritime activities. Today, there are rapidly developing research interests in the biota attracted to freely floating (i.e. pelagic) marine debris, commonly known as ‘hangers-on and hitch-hikers’ as well as material sinking to the sea floor despite being buoyant. Dispersal of aggressive alien and invasive species by these mechanisms leads one to reflect on the possibilities that ensuing invasions could endanger sensitive, or at-risk coastal environments (both marine and terrestrial) far from their native habitats. PMID:19528053

Life in the "plastisphere": microbial communities on plastic marine debris.

PubMed

Zettler, Erik R; Mincer, Tracy J; Amaral-Zettler, Linda A

2013-07-02

Plastics are the most abundant form of marine debris, with global production rising and documented impacts in some marine environments, but the influence of plastic on open ocean ecosystems is poorly understood, particularly for microbial communities. Plastic marine debris (PMD) collected at multiple locations in the North Atlantic was analyzed with scanning electron microscopy (SEM) and next-generation sequencing to characterize the attached microbial communities. We unveiled a diverse microbial community of heterotrophs, autotrophs, predators, and symbionts, a community we refer to as the "Plastisphere". Pits visualized in the PMD surface conformed to bacterial shapes suggesting active hydrolysis of the hydrocarbon polymer. Small-subunit rRNA gene surveys identified several hydrocarbon-degrading bacteria, supporting the possibility that microbes play a role in degrading PMD. Some Plastisphere members may be opportunistic pathogens (the authors, unpublished data) such as specific members of the genus Vibrio that dominated one of our plastic samples. Plastisphere communities are distinct from surrounding surface water, implying that plastic serves as a novel ecological habitat in the open ocean. Plastic has a longer half-life than most natural floating marine substrates, and a hydrophobic surface that promotes microbial colonization and biofilm formation, differing from autochthonous substrates in the upper layers of the ocean.

Millimeter-sized marine plastics: a new pelagic habitat for microorganisms and invertebrates.

PubMed

Reisser, Julia; Shaw, Jeremy; Hallegraeff, Gustaaf; Proietti, Maira; Barnes, David K A; Thums, Michele; Wilcox, Chris; Hardesty, Britta Denise; Pattiaratchi, Charitha

2014-01-01

Millimeter-sized plastics are abundant in most marine surface waters, and known to carry fouling organisms that potentially play key roles in the fate and ecological impacts of plastic pollution. In this study we used scanning electron microscopy to characterize biodiversity of organisms on the surface of 68 small floating plastics (length range = 1.7-24.3 mm, median = 3.2 mm) from Australia-wide coastal and oceanic, tropical to temperate sample collections. Diatoms were the most diverse group of plastic colonizers, represented by 14 genera. We also recorded 'epiplastic' coccolithophores (7 genera), bryozoans, barnacles (Lepas spp.), a dinoflagellate (Ceratium), an isopod (Asellota), a marine worm, marine insect eggs (Halobates sp.), as well as rounded, elongated, and spiral cells putatively identified as bacteria, cyanobacteria, and fungi. Furthermore, we observed a variety of plastic surface microtextures, including pits and grooves conforming to the shape of microorganisms, suggesting that biota may play an important role in plastic degradation. This study highlights how anthropogenic millimeter-sized polymers have created a new pelagic habitat for microorganisms and invertebrates. The ecological ramifications of this phenomenon for marine organism dispersal, ocean productivity, and biotransfer of plastic-associated pollutants, remains to be elucidated.

Millimeter-Sized Marine Plastics: A New Pelagic Habitat for Microorganisms and Invertebrates

PubMed Central

Reisser, Julia; Shaw, Jeremy; Hallegraeff, Gustaaf; Proietti, Maira; Barnes, David K. A.; Thums, Michele; Wilcox, Chris; Hardesty, Britta Denise; Pattiaratchi, Charitha

2014-01-01

Millimeter-sized plastics are abundant in most marine surface waters, and known to carry fouling organisms that potentially play key roles in the fate and ecological impacts of plastic pollution. In this study we used scanning electron microscopy to characterize biodiversity of organisms on the surface of 68 small floating plastics (length range = 1.7–24.3 mm, median = 3.2 mm) from Australia-wide coastal and oceanic, tropical to temperate sample collections. Diatoms were the most diverse group of plastic colonizers, represented by 14 genera. We also recorded ‘epiplastic’ coccolithophores (7 genera), bryozoans, barnacles (Lepas spp.), a dinoflagellate (Ceratium), an isopod (Asellota), a marine worm, marine insect eggs (Halobates sp.), as well as rounded, elongated, and spiral cells putatively identified as bacteria, cyanobacteria, and fungi. Furthermore, we observed a variety of plastic surface microtextures, including pits and grooves conforming to the shape of microorganisms, suggesting that biota may play an important role in plastic degradation. This study highlights how anthropogenic millimeter-sized polymers have created a new pelagic habitat for microorganisms and invertebrates. The ecological ramifications of this phenomenon for marine organism dispersal, ocean productivity, and biotransfer of plastic-associated pollutants, remains to be elucidated. PMID:24941218

Environmental implications of plastic debris in marine settings--entanglement, ingestion, smothering, hangers-on, hitch-hiking and alien invasions.

PubMed

Gregory, Murray R

2009-07-27

Over the past five or six decades, contamination and pollution of the world's enclosed seas, coastal waters and the wider open oceans by plastics and other synthetic, non-biodegradable materials (generally known as 'marine debris') has been an ever-increasing phenomenon. The sources of these polluting materials are both land- and marine-based, their origins may be local or distant, and the environmental consequences are many and varied. The more widely recognized problems are typically associated with entanglement, ingestion, suffocation and general debilitation, and are often related to stranding events and public perception. Among the less frequently recognized and recorded problems are global hazards to shipping, fisheries and other maritime activities. Today, there are rapidly developing research interests in the biota attracted to freely floating (i.e. pelagic) marine debris, commonly known as 'hangers-on and hitch-hikers' as well as material sinking to the sea floor despite being buoyant. Dispersal of aggressive alien and invasive species by these mechanisms leads one to reflect on the possibilities that ensuing invasions could endanger sensitive, or at-risk coastal environments (both marine and terrestrial) far from their native habitats.

General circulation of the South Atlantic between 5 deg N and 35 deg S

NASA Technical Reports Server (NTRS)

Ollitrault, Michel; Mercier, H.; Blanc, F.; Letraon, L. Y.

1991-01-01

The TOPEX/POSEIDON altimeter will provide the temporal mean seal level. So, secondly, we propose to compute the difference between these two surfaces (mean sea level minus general circulation dynamic topography). The result will be an estimate of the marine geoid, which is time invariant for the 5-year period under consideration. If this geoid is precise enough, it will permit a description of seasonal variability of the large-scale surface circulation. If there happens to be enough float data, it may be possible to infer the first vertical modes of this variability. Thus the main goal of our investigation is to determine the 3-D general circulation of the South Atlantic and the large-scale seasonal fluctuations. This last objective, however, may be restricted to the western part of the South Atlantic because float deployments have been scheduled only in the Brasil basin.

Microgravity

NASA Image and Video Library

1985-08-08

The lack of normal convection in microgravity is demonstrated by a carbonated soft drink floating in the middeck of the Space Shuttle. While the droplet is oscillating slightly and starting to assume a spherical shape, it is filled with carbon dioxide bubbles in a range of sizes. On Earth, the bubbles would quickly foat up to form a head. In space, they are suspended. They may drift with time and eventually the surface tension between individual bubbles breaks, allowing larger bubbles to form. This image was taken during STS-51F mission (Spacelab 2) which carried test models of dispensers from two pupular soft drink manufacturers. Photo credit: NASA/Johnson Space Center (JSC)

Interfacial Bubble Deformations

NASA Astrophysics Data System (ADS)

Seymour, Brian; Shabane, Parvis; Cypull, Olivia; Cheng, Shengfeng; Feitosa, Klebert

Soap bubbles floating at an air-water experience deformations as a result of surface tension and hydrostatic forces. In this experiment, we investigate the nature of such deformations by taking cross-sectional images of bubbles of different volumes. The results show that as their volume increases, bubbles transition from spherical to hemispherical shape. The deformation of the interface also changes with bubble volume with the capillary rise converging to the capillary length as volume increases. The profile of the top and bottom of the bubble and the capillary rise are completely determined by the volume and pressure differences. James Madison University Department of Physics and Astronomy, 4VA Consortium, Research Corporation for Advancement of Science.

Total petroleum systems of the Bonaparte Gulf Basin area, Australia; Jurassic, Early Cretaceous-Mesozoic; Keyling, Hyland Bay-Permian; Milligans-Carboniferous, Permian

USGS Publications Warehouse

Bishop, M.G.

1999-01-01

The Bonaparte Gulf Basin Province (USGS #3910) of northern Australia contains three important hydrocarbon source-rock intervals. The oldest source-rock interval and associated reservoir rocks is the Milligans-Carboniferous, Permian petroleum system. This petroleum system is located at the southern end of Joseph Bonaparte Gulf and includes both onshore and offshore areas within a northwest to southeast trending Paleozoic rift that was initiated in the Devonian. The Milligans Formation is a Carboniferous marine shale that sources accumulations of both oil and gas in Carboniferous and Permian deltaic, marine shelf carbonate, and shallow to deep marine sandstones. The second petroleum system in the Paleozoic rift is the Keyling, Hyland Bay-Permian. Source rocks include Lower Permian Keyling Formation delta-plain coals and marginal marine shales combined with Upper Permian Hyland Bay Formation prodelta shales. These source-rock intervals provide gas and condensate for fluvial, deltaic, and shallow marine sandstone reservoirs primarily within several members of the Hyland Bay Formation. The Keyling, Hyland Bay-Permian petroleum system is located in the Joseph Bonaparte Gulf, north of the Milligans-Carboniferous, Permian petroleum system, and may extend northwest under the Vulcan graben sub-basin. The third and youngest petroleum system is the Jurassic, Early Cretaceous-Mesozoic system that is located seaward of Joseph Bonaparte Gulf on the Australian continental shelf, and trends southwest-northeast. Source-rock intervals in the Vulcan graben sub-basin include deltaic mudstones of the Middle Jurassic Plover Formation and organic-rich marine shales of the Upper Jurassic Vulcan Formation and Lower Cretaceous Echuca Shoals Formation. These intervals produce gas, oil, and condensate that accumulates in, shallow- to deep-marine sandstone reservoirs of the Challis and Vulcan Formations of Jurassic to Cretaceous age. Organic-rich, marginal marine claystones and coals of the Plover Formation (Lower to Upper Jurassic), combined with marine claystones of the Flamingo Group and Darwin Formation (Upper Jurassic to Lower Cretaceous) comprise the source rocks for the remaining area of the system. These claystones and coals source oil, gas, and condensate accumulations in reservoirs of continental to marine sandstones of the Plover Formation and Flamingo Group. Shales of the regionally distributed Lower Cretaceous Bathurst Island Group and intraformational shales act as seals for hydrocarbons trapped in anticlines and fault blocks, which are the major traps of the province. Production in the Bonaparte Gulf Basin Province began in 1986 using floating production facilities, and had been limited to three offshore fields located in the Vulcan graben sub-basin. Cumulative production from these fields totaled more than 124 million barrels of oil before the facilities were removed after production fell substantially in 1995. Production began in 1998 from three offshore wells in the Zone of Cooperation through floating production facilities. After forty years of exploration, a new infrastructure of pipelines and facilities are planned to tap already discovered offshore reserves and to support additional development.

Light Scattering by Marine Particles: Modeling with Non-spherical Shapes

DTIC Science & Technology

2011-09-30

coccoliths detached from Emiliania huxleyi, Limnology and Oceanography, 46, 1438−1454, 2001. Gordon, H.R., T.J. Smyth, W.M. Balch, and G.C. Boynton...Light scattering by coccoliths detached from Emiliania huxleyi, Applied Optics, (2009). PUBLICATIONS H.R. Gordon, Light scattering by randomly

Light Scattering by Marine Particles: Modeling with Non-spherical Shapes

DTIC Science & Technology

2008-01-01

Emiliania huxleyi, Limnology and Oceanography, 46, 1438−1454. Gordon, H.R., 2004, Inverse Radiative Transfer, Coccolith Backscattering, and Light Scattering...16430. Voss, K.J., W.M. Balch, and K.A. Kilpatrick, 1998, Scattering and attenuation properties of Emiliania huxleyi cells and their detached

Standard Practice for the Selection and Application of Marine Deck Coverings

DTIC Science & Technology

1992-07-01

floors to reduce the transmission of noise and vibrations. These typically consist of layers of mineral wool or mineral wool panel sections with a...crew efficiency. Floating deck systems are generally composed of an insulating material such as mineral wool that are laid loose on the structural...Chapter II-2, Part A, Regulation 3(c). Sound Reduction Index - 44 dB Sound Insulation Index (Ia) - 47 dB Density of Mineral Wool - 10 pounds per

Dangerous hitchhikers? Evidence for potentially pathogenic Vibrio spp. on microplastic particles.

PubMed

Kirstein, Inga V; Kirmizi, Sidika; Wichels, Antje; Garin-Fernandez, Alexa; Erler, Rene; Löder, Martin; Gerdts, Gunnar

2016-09-01

The taxonomic composition of biofilms on marine microplastics is widely unknown. Recent sequencing results indicate that potentially pathogenic Vibrio spp. might be present on floating microplastics. Hence, these particles might function as vectors for the dispersal of pathogens. Microplastics and water samples collected in the North and Baltic Sea were subjected to selective enrichment for pathogenic Vibrio species. Bacterial colonies were isolated from CHROMagar™Vibrio and assigned to Vibrio spp. on the species level by MALDI-TOF MS (Matrix Assisted Laser Desorption/Ionisation - Time of Flight Mass Spectrometry). Respective polymers were identified by ATR FT-IR (Attenuated Total Reflectance Fourier Transform - Infrared Spectroscopy). We discovered potentially pathogenic Vibrio parahaemolyticus on a number of microplastic particles, e.g. polyethylene, polypropylene and polystyrene from North/Baltic Sea. This study confirms the indicated occurrence of potentially pathogenic bacteria on marine microplastics and highlights the urgent need for detailed biogeographical analyses of marine microplastics. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mapping coastal marine debris using aerial imagery and spatial analysis.

PubMed

Moy, Kirsten; Neilson, Brian; Chung, Anne; Meadows, Amber; Castrence, Miguel; Ambagis, Stephen; Davidson, Kristine

2017-12-19

This study is the first to systematically quantify, categorize, and map marine macro-debris across the main Hawaiian Islands (MHI), including remote areas (e.g., Niihau, Kahoolawe, and northern Molokai). Aerial surveys were conducted over each island to collect high resolution photos, which were processed into orthorectified imagery and visually analyzed in GIS. The technique provided precise measurements of the quantity, location, type, and size of macro-debris (>0.05m 2 ), identifying 20,658 total debris items. Northeastern (windward) shorelines had the highest density of debris. Plastics, including nets, lines, buoys, floats, and foam, comprised 83% of the total count. In addition, the study located six vessels from the 2011 Tōhoku tsunami. These results created a baseline of the location, distribution, and composition of marine macro-debris across the MHI. Resource managers and communities may target high priority areas, particularly along remote coastlines where macro-debris counts were largely undocumented. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multichannel seismic/oceanographic/biological monitoring of the oceans

NASA Astrophysics Data System (ADS)

Hello, Y.; Leymarie, E.; Ogé, A.; Poteau, A.; Argentino, J.; Sukhovich, A.; Claustre, H.; Nolet, G.

2011-12-01

Delays in seismic P wave are used to make scans or 3D images of the variations in seismic wave speed in the Earth's interior using the techniques of seismic tomography. Observations of such delays are ubiquitous on the continents but rare in oceanic regions. Free-drifting profiling floats that measure the temperature, salinity and current of the upper 2000 m of the ocean are used by physical oceanographers for continuous monitoring in the Argo program. Recently, seismologists developed the idea to use such floats in order to compensate for the lack of seismic delay observations, especially in the southern hemisphere. In project Globalseis, financed by a grant from the European Research Council (ERC), we have developed and tested a prototype of such a seismological sensor using an Apex float from Teledyne Webb Research, a Rafos hydrophone, and electronics developed in collaboration with Osean, a small engineering firm in France. `MERMAID', for `Mobile Earthquake Recorder in Marine Areas by Independent Divers' is approaching its final design and should become available off the shelf in 2012. In the meantime we initiated a collaboration between Globalseis and another ERC project, remOcean, for the acquisition of radiometric, bio-geochemical data and meteorological observations in addition to salinity and temperature (Bio-Argo program). In this collaboration of Geoazur and LOV (Laboratoire d'Océanologie de Villefranche sur mer), two laboratories located at the Observatory of Villefranche, we developed a multichannel acquisition hardware electronics called 'PAYLOAD' that allows commercial floats such as Apex (TWR) and Provor (NKE) to serve multiple observing missions simultaneously. Based on an algorithm using wavelet transforms PAYLOAD continuously analyzes acoustic signals to detect major seismic events and weather phenomena such rain, drizzle, open sea and ice during drift diving phase. The bio-geochemical and other parameters are recorded and analyzed during ascent. All data are transmitted using the Iridum satellite network in Rudics mode when the floats surface. Two-way communication with Iridium allows us to send new parameters to the float for its next mission. Dual project campaigns are envisaged for next year.

Transforming Ocean Observations of the Carbon Budget, Acidification, Hypoxia, Nutrients, and Biological Productivity: a Global Array of Biogeochemical Argo Floats

NASA Astrophysics Data System (ADS)

Talley, L. D.; Johnson, K. S.; Claustre, H.; Boss, E.; Emerson, S. R.; Westberry, T. K.; Sarmiento, J. L.; Mazloff, M. R.; Riser, S.; Russell, J. L.

2017-12-01

Our ability to detect changes in biogeochemical (BGC) processes in the ocean that may be driven by increasing atmospheric CO2, as well as by natural climate variability, is greatly hindered by undersampling in vast areas of the open ocean. Argo is a major international program that measures ocean heat content and salinity with about 4000 floats distributed throughout the ocean, profiling to 2000 m every 10 days. Extending this approach to a global BGC-Argo float array, using recent, proven sensor technology, and in close synergy with satellite systems, will drive a transformative shift in observing and predicting the effects of climate change on ocean metabolism, carbon uptake, acidification, deoxygenation, and living marine resource management. BGC-Argo will add sensors for pH, oxygen, nitrate, chlorophyll, suspended particles, and downwelling irradiance, with sufficient accuracy for climate studies. Observing System Simulation Experiments (OSSEs) using BGC models indicate that 1000 BGC floats would provide sufficient coverage, hence equipping 1/4 of the Argo array. BGC-Argo (http://biogeochemical-argo.org) will enhance current sustained observational programs such as Argo, GO-SHIP, and long-term ocean time series. BGC-Argo will benefit from deployments on GO-SHIP vessels, which provide sensor verification. Empirically derived algorithms that relate the observed BGC float parameters to the carbon system parameters will provide global information on seasonal ocean-atmosphere carbon exchange. BGC Argo measurements could be paired with other emerging technology, such as pCO2 measurements from ships of opportunity and wave gliders, to extend and validate exchange estimates. BGC-Argo prototype programs already show the potential of a global observing system that can measure seasonal to decadal variability. Various countries have developed regional BGC arrays: Southern Ocean (SOCCOM), North Atlantic Subpolar Gyre (remOcean), Mediterranean (NAOS), the Kuroshio (INBOX), and Indian Ocean (IOBioArgo). As examples, bio-optical sensors are identifying regional anomalies in light attenuation/scattering, with implications for ocean productivity and carbon export; SOCCOM floats show high CO2 outgassing in the Antarctic Circumpolar Current, due to previously unmeasured winter fluxes.

Manipulating particles for micro- and nano-fluidics via floating electrodes and diffusiophoresis

NASA Astrophysics Data System (ADS)

Yalcin, Sinan Eren

The ability to accurately control micro- and nano-particles in a liquid is fundamentally useful for many applications in biology, medicine, pharmacology, tissue engineering, and microelectronics. Therefore, first particle manipulations are experimentally studied using electrodes attached to the bottom of a straight microchannel under an imposed DC or AC electric field. In contrast to a dielectric microchannel possessing a nearly-uniform surface charge, a floating electrode is polarized under the imposed electric field. The purpose is to create a non-uniform distribution of the induced surface charge, with a zero-net-surface charge along the floating electrode's surface. Such a field, in turn, generates an induced-charge electro-osmotic (ICED) flow near the metal strip. The demonstrations by using single and multiple floating electrodes at the bottom of a straight microchannel, with induced DC electric field, include particle enrichment, movement, trapping, reversal of motion, separation, and particle focusing. A flexible strategy for the on-demand control of the particle enrichment and positioning is also proposed and demonstrated by using a locally-controlled floating metal electrode. Then, under an externally imposed AC electric field, the particle deposition onto a floating electrode, which is placed in a closed circular cavity, has been experimentally investigated. In the second part of the study, another particle manipulation method was computationally investigated. The diffusiophoretic and electrodiffusiophoretic motion of a charged spherical particle in a nanopore is subjected to an axial electrolyte concentration gradient. The charged particle experiences electrophoresis because of the imposed electric field and the diffusiophoresis is caused solely by the imposed concentration gradient. Depending on the magnitude and direction of the imposed concentration gradient, the particle's electrophoretic motion can be accelerated, decelerated, and even reversed in a nanopore by the superimposed diffusiophoresis. Based on the results demonstrated in the present study, it is entirely conceivable to extend the development to design devices for the following objectives: (1) to enrich the concentration of, say, DNA or RNA, and to increase their concentrations at a desired location. (2) to act as a filtration device, wherin the filtration can be achieved without blocking the microfluidic channel and without any porous material. (3) to act as a microfluidic valve, where the particles can be locally trapped in any desired location and the direction can be switched as desired. (4) to create nanocomposite material formation or even a thin nanocomposite film formation on the floating electrode. (5) to create a continuous concentration-gradient-generator nanofluidic device that may be obtained for nanoparticle translocation process. This may achieve nanometer-scale spatial accuracy sample sequencing by simultaneously controlling the electric field and concentration gradient.

VLF Source Localization with a Freely Drifting Acoustic Sensor Array

DTIC Science & Technology

1992-09-01

A,’. vol. 89, no. 3, pp. 1134-1158, March 1991. D’Spain, G. L., W. S. Hodgkiss, and G. L. Edmonds, "The Simultaneous Measurement of Infra - sonic ...RESULTS Marine Physical Laboratory’s set of nine freely drifting, infrasonic sensors, capable of record- ing ocean ambient noise in the I- to 25-Hz range...provide thc ship’s thrust, are a well-known contributor to the infrasonic sound field [Ross, 1976; D’Spain et. al., 1991]. The Swallow float deployment

Efficient Atomization and Combustion of Emulsified Crude Oil

DTIC Science & Technology

2014-09-18

2.26 Naphthenes , vol % 50.72 Aromatics, vol % 16.82 Freezing Point, °F -49.7 Freezing Point, °C -45.4 Smoke Point, mm (ASTM) 19.2 Acid ...needed by the proposed method for capturing and oil removal , in particular the same vessels and booms used to herd the floating crude oil into a thick...slicks need to be removed more rapidly than they can be transported, in situ burning offers a rapid disposal method that minimizes risk to marine life

Legislation would establish commission to assess marine and coastal resources and develop national ocean policy

NASA Astrophysics Data System (ADS)

Showstack, Randy

During 1998, internationally designated as the year of the ocean, perhaps more people are paying heed to the deep seas now than ever before.Transfixed to the big screen by this year's movie blockbuster, they anticipate when the Titanic will scrape into the iceberg and break apart, shiver when household-name heartthrobs Leonardo DiCaprio and Kate Winslet float on the freezing waters, and hum along to the theme sung by Celine Dion.

Spacecraft charging analysis with the implicit particle-in-cell code iPic3D

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

Deca, J.; Lapenta, G.; Marchand, R.

2013-10-15

We present the first results on the analysis of spacecraft charging with the implicit particle-in-cell code iPic3D, designed for running on massively parallel supercomputers. The numerical algorithm is presented, highlighting the implementation of the electrostatic solver and the immersed boundary algorithm; the latter which creates the possibility to handle complex spacecraft geometries. As a first step in the verification process, a comparison is made between the floating potential obtained with iPic3D and with Orbital Motion Limited theory for a spherical particle in a uniform stationary plasma. Second, the numerical model is verified for a CubeSat benchmark by comparing simulation resultsmore » with those of PTetra for space environment conditions with increasing levels of complexity. In particular, we consider spacecraft charging from plasma particle collection, photoelectron and secondary electron emission. The influence of a background magnetic field on the floating potential profile near the spacecraft is also considered. Although the numerical approaches in iPic3D and PTetra are rather different, good agreement is found between the two models, raising the level of confidence in both codes to predict and evaluate the complex plasma environment around spacecraft.« less

Effects of Second-Order Hydrodynamics on a Semisubmersible Floating Offshore Wind Turbine: Preprint

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

Bayati, I.; Jonkman, J.; Robertson, A.

2014-07-01

The objective of this paper is to assess the second-order hydrodynamic effects on a semisubmersible floating offshore wind turbine. Second-order hydrodynamics induce loads and motions at the sum- and difference-frequencies of the incident waves. These effects have often been ignored in offshore wind analysis, under the assumption that they are significantly smaller than first-order effects. The sum- and difference-frequency loads can, however, excite eigenfrequencies of the system, leading to large oscillations that strain the mooring system or vibrations that cause fatigue damage to the structure. Observations of supposed second-order responses in wave-tank tests performed by the DeepCwind consortium at themore » MARIN offshore basin suggest that these effects might be more important than originally expected. These observations inspired interest in investigating how second-order excitation affects floating offshore wind turbines and whether second-order hydrodynamics should be included in offshore wind simulation tools like FAST in the future. In this work, the effects of second-order hydrodynamics on a floating semisubmersible offshore wind turbine are investigated. Because FAST is currently unable to account for second-order effects, a method to assess these effects was applied in which linearized properties of the floating wind system derived from FAST (including the 6x6 mass and stiffness matrices) are used by WAMIT to solve the first- and second-order hydrodynamics problems in the frequency domain. The method has been applied to the OC4-DeepCwind semisubmersible platform, supporting the NREL 5-MW baseline wind turbine. The loads and response of the system due to the second-order hydrodynamics are analysed and compared to first-order hydrodynamic loads and induced motions in the frequency domain. Further, the second-order loads and induced response data are compared to the loads and motions induced by aerodynamic loading as solved by FAST.« less

Laboratory simulation of the electrodynamic interactions of a tethered satellite with an ionospheric plasma

NASA Technical Reports Server (NTRS)

Bonifazi, C.; Lebreton, J. P.; Vannaroni, G.; Cosmovici, C.; Debrie, R.; Hamelin, M.; Pomathiod, L.; Arends, H.

1986-01-01

An improved experimental set-up in the Orleans Plasma Chamber allowed investigations of the I-V characteristics of a conductive spherical body (10 cm diameter) in a plasma environment. Moreover, the influence of a transversal magnetic field at 0.6 and 1.2 G was investigated, for the first time, both on the sheath potential profile and current collection. Floating potential profiles were measured at 16 different radial distances from the test body up to 9 body radii in 8 different angular positions. The test body potential could be increased in the range from -200 V up to +100 V. Preliminary results are shown and discussed.

Evaluation of anti-GERD activity of gastro retentive drug delivery system of itopride hydrochloride.

PubMed

Satapathy, Trilochan; Panda, Prasana K; Goyal, Amit K; Rath, Goutam

2010-08-01

The present work describes the formulation and evaluation of the gastroretentive system of Itopride hydrochloride. In this research, we have formulated floating hydrogel-based microspheres employing calcium carbonate (CaCO(3)) as a gas forming agent dispersed in alginate matrix. In vitro characterizations such as drug content, particle size, and drug release were carried out. GI motility was determined by administration of charcoal meal to rats. Results demonstrated that prepared microspheres were spherical in shape with smooth surface, good loading efficiency, and excellent buoyancy. The gastro retentive dosage form of itiopride demonstrated significant antacid, anti-ulcer, and anti-GERD activity after 12 hours in comparison with the conventional dosage form.

Prediction of large negative shaded-side spacecraft potentials

NASA Technical Reports Server (NTRS)

Prokopenko, S. M. L.; Laframboise, J. G.

1977-01-01

A calculation by Knott, for the floating potential of a spherically symmetric synchronous-altitude satellite in eclipse, was adapted to provide simple calculations of upper bounds on negative potentials which may be achieved by electrically isolated shaded surfaces on spacecraft in sunlight. Large (approximately 60 percent) increases in predicted negative shaded-side potentials are obtained. To investigate effective potential barrier or angular momentum selection effects due to the presence of less negative sunlit-side or adjacent surface potentials, these expressions were replaced by the ion random current, which is a lower bound for convex surfaces when such effects become very severe. Further large increases in predicted negative potentials were obtained, amounting to a doubling in some cases.

On computing special functions in marine engineering

NASA Astrophysics Data System (ADS)

Constantinescu, E.; Bogdan, M.

2015-11-01

Important modeling applications in marine engineering conduct us to a special class of solutions for difficult differential equations with variable coefficients. In order to be able to solve and implement such models (in wave theory, in acoustics, in hydrodynamics, in electromagnetic waves, but also in many other engineering fields), it is necessary to compute so called special functions: Bessel functions, modified Bessel functions, spherical Bessel functions, Hankel functions. The aim of this paper is to develop numerical solutions in Matlab for the above mentioned special functions. Taking into account the main properties for Bessel and modified Bessel functions, we shortly present analytically solutions (where possible) in the form of series. Especially it is studied the behavior of these special functions using Matlab facilities: numerical solutions and plotting. Finally, it will be compared the behavior of the special functions and point out other directions for investigating properties of Bessel and spherical Bessel functions. The asymptotic forms of Bessel functions and modified Bessel functions allow determination of important properties of these functions. The modified Bessel functions tend to look more like decaying and growing exponentials.

Floating marine debris in fjords, gulfs and channels of southern Chile.

PubMed

Hinojosa, Iván A; Thiel, Martin

2009-08-01

Floating marine debris (FMD) is reported from all oceans. The bulk of FMD are plastics, which due to their longevity cause multiple negative impacts on wildlife and environment. Identifying the origins of FMD (land- or sea-based) is important to take the necessary steps to diminish their abundance. Using ship surveys we examined the abundance, composition and distribution of FMD during the years 2002-2005 in the fjords, gulfs and channels of southern Chile. Abundances of FMD were relatively high compared with other studies, ranging from 1 to 250 items km(-2). The majority (approximately 80%) of FMD was composed of styrofoam (expanded polystyrene), plastic bags and plastic fragments. Styrofoam, which is intensively used as flotation device by mussel farms, was very abundant in the northern region but rarely occurred in the southern region of the study area. Food sacks from salmon farms were also most common in the northern region, where approximately 85% of the total Chilean mussel and salmon harvest is produced. Plastic bags, which could be from land- or sea-based sources, were found throughout the entire study area. Our results indicate that sea-based activities (mussel farming and salmon aquaculture) are responsible for most FMD in the study area. In order to reduce FMDs in the environment, in addition to stronger legislation and identification of potential sources, we suggest environmental education programs and we encourage public participation (e.g. in beach surveys and clean-ups).

Natural attenuation of contaminated marine sediments from an old floating dock Part II: changes of sediment microbial community structure and its relationship with environmental variables.

PubMed

Wang, Ya-Fen; Tam, Nora Fung-Yee

2012-04-15

Changes of microbial community structure and its relationship with various environmental variables in surface marine sediments were examined for a one-year period after the removal of an old floating dock in Hong Kong SAR, South China. Temporal variations in the microbial community structure were clearly revealed by principal component analysis (PCA) of the microbial ester-linked fatty acid methyl ester (EL-FAME) profiles. The most obvious shift in microbial community structure was detected 6 months after the removal of the dock, although no significant decline in the levels of pollutants could be detected. As determined by EL-FAME profiles, the microbial diversity recovered and the predominance of gram-negative bacteria was gradually replaced by gram-positive bacteria and fungi in the impacted stations. With redundancy analysis (RDA), the concentration of total polycyclic aromatic hydrocarbons (PAHs) was found to be the second important determinant of microbial community structure, next to Time. The relative abundance of 18:1ω9c and hydroxyl fatty acids enriched in the PAH hot spots, whereas 16:1ω9 and 18:1ω9t were negatively correlated to total PAH concentration. The significant relationships observed between microbial EL-FAME profiles and pollutants, exampled by PAHs in the present study, suggested the potential of microbial community analysis in the assessment of the natural attenuation process in contaminated environments. Copyright © 2012 Elsevier B.V. All rights reserved.

Numerical investigation of interactions between marine atmospheric boundary layer and offshore wind farm

NASA Astrophysics Data System (ADS)

Lyu, Pin; Chen, Wenli; Li, Hui; Shen, Lian

2017-11-01

In recent studies, Yang, Meneveau & Shen (Physics of Fluids, 2014; Renewable Energy, 2014) developed a hybrid numerical framework for simulation of offshore wind farm. The framework consists of simulation of nonlinear surface waves using a high-order spectral method, large-eddy simulation of wind turbulence on a wave-surface-fitted curvilinear grid, and an actuator disk model for wind turbines. In the present study, several more precise wind turbine models, including the actuator line model, actuator disk model with rotation, and nacelle model, are introduced into the computation. Besides offshore wind turbines on fixed piles, the new computational framework has the capability to investigate the interaction among wind, waves, and floating wind turbines. In this study, onshore, offshore fixed pile, and offshore floating wind farms are compared in terms of flow field statistics and wind turbine power extraction rate. The authors gratefully acknowledge financial support from China Scholarship Council (No. 201606120186) and the Institute on the Environment of University of Minnesota.

Self-assembled diatom substrates with plasmonic functionality

NASA Astrophysics Data System (ADS)

Kwon, Sun Yong; Park, Sehyun; Nichols, William T.

2014-04-01

Marine diatoms have an exquisitely complex exoskeleton that is promising for engineered surfaces such as sensors and catalysts. For such applications, creating uniform arrays of diatom frustules across centimeter scales will be necessary. Here, we present a simple, low-cost floating interface technique to self-assemble the diatom frustules. We show that well-prepared diatoms form floating hexagonal close-packed arrays at the air-water interface that can be transferred directly to a substrate. We functionalize the assembled diatom surfaces with gold and characterize the plasmonic functionality by using surface enhanced Raman scattering (SERS). Thin gold films conform to the complex, hierarchical diatom structure and produce a SERS enhancement factor of 2 × 104. Small gold nanoparticles attached to the diatom's surface produce a higher enhancement of 7 × 104 due to stronger localization of the surface plasmons. Taken together, the large-scale assembly and plasmonic functionalization represent a promising platform to control the energy and the material flows at a complex surface for applications such as sensors and plasmonic enhanced catalysts.

Plastic accumulation in the Mediterranean sea.

PubMed

Cózar, Andrés; Sanz-Martín, Marina; Martí, Elisa; González-Gordillo, J Ignacio; Ubeda, Bárbara; Gálvez, José Á; Irigoien, Xabier; Duarte, Carlos M

2015-01-01

Concentrations of floating plastic were measured throughout the Mediterranean Sea to assess whether this basin can be regarded as a great accumulation region of plastic debris. We found that the average density of plastic (1 item per 4 m2), as well as its frequency of occurrence (100% of the sites sampled), are comparable to the accumulation zones described for the five subtropical ocean gyres. Plastic debris in the Mediterranean surface waters was dominated by millimeter-sized fragments, but showed a higher proportion of large plastic objects than that present in oceanic gyres, reflecting the closer connection with pollution sources. The accumulation of floating plastic in the Mediterranean Sea (between 1,000 and 3,000 tons) is likely related to the high human pressure together with the hydrodynamics of this semi-enclosed basin, with outflow mainly occurring through a deep water layer. Given the biological richness and concentration of economic activities in the Mediterranean Sea, the affects of plastic pollution on marine and human life are expected to be particularly frequent in this plastic accumulation region.

MULTIMERMAID for Mariscope. A dedicated Accoustic Float for Monitoring of the Oceans

NASA Astrophysics Data System (ADS)

Hello, Y.; Bonnieux, S.; Argentino, J. F.; Yegikyan, M.; Nolet, G.

2014-12-01

Delays of seismic P waves are used to make scans or 3D images of the variations in seismic wave speed in the Earth's interior using the techniques of seismic tomography. Observations of such delays are ubiquitous on the continents but rare in oceanic regions, mostly because of the large cost associated with deploying ocean-bottom seismometers. At the same time, several thousand free-drifting profiling floats measure the temperature, salinity and current of the upper 2000 m of the ocean in the Argo program, but are incapable to record and transmit seismic signals. Simons et al. (JGR, 2009) developed the idea to use such floats in order to compensate for the lack of seismic delay observations, especially in the southern hemisphere. We built and tested a prototype of such a seismological sensor using an Apex float from Teledyne Webb Research, a Rafos hydrophone, and electronics developed in collaboration with Osean. Since 2012, these floats have been deployed in the Mediterranean, in the South Indian Ocean, and more recently near the Galapagos islands in the Pacific (see abstract by Nolet et al.). A new prototype " MultiMermaid " spherical is at present in final phase of validation. Using a 37" glass sphere, the lithium battery capacity is greatly superior to that of the Mermaid. It has an instrument compartment that allows for multidisciplinary observations (seismic and kHz acoustics, magnetic field, temperature, bathymetry) and will be programmable. The maximum depth will be 3-4 km. Battery consumption by the pump has been reduced, and the durability depends mostly on CPU usage while drifting, amount of data transmitted but should be five years or more. The Multimermaid can serve biologists by providing a global monitoring of whale and dolphin sounds, seismic tomography by providing worldwide coverage of P wave arrival times, and oceanographers by providing ocean temperature, bathymetry and information on deep currents. Based on an ARM-Cortex M4 microprocessor, Multimermaid can accept any new features such as the possibility of a local rapid response network in which the instruments locate themselves while under water, and provided the possibility for users to modify monitoring software after deployment. In order to extend the life time of Multimermaid we are also investigating to add an optional green renewable power source.

Seasonal variability in ice-front position, glacier speed, and surface elevation at Helheim Glacier, SE Greenland, from 2010-2016

NASA Astrophysics Data System (ADS)

Kehrl, L. M.; Joughin, I. R.; Shean, D. E.

2016-12-01

Marine-terminating glaciers can be very sensitive to changes in ice-front position, depending on their geometry. If a nearly grounded glacier retreats into deeper water, the glacier typically must speed up to produce the additional longitudinal and lateral stress gradients necessary to restore force balance. This speedup often causes thinning, which can increase the glacier's susceptibility to further retreat. In this study, we combine satellite observations and numerical modeling (Elmer/Ice) to investigate how seasonal changes in ice-front position affect glacier speed and surface elevation at Helheim Glacier, SE Greenland, from 2010-2016. Helheim's calving front position fluctuated about a mean position from 2010-2016. During 2010/11, 2013/14, and 2015/16, Helheim seasonally retreated and advanced along a reverse bed slope by > 3 km. During these years, the glacier retreated from winter/spring to late summer and then readvanced until winter/spring. During the retreat, Helheim sped up by 20-30% and thinned by 20 m near its calving front. This thinning caused the calving front to unground, and a floating ice tongue was then able to readvance over the following winter with limited iceberg calving. The advance, which continued until the glacier reached the top of the bathymetric high, caused the glacier to slow and thicken. During years when Helheim likely did not form a floating ice tongue, iceberg calving continued throughout the winter. Consequently, the formation of this floating ice tongue may have helped stabilize Helheim after periods of rapid retreat and dynamic thinning. Helheim's rapid retreat from 2001-2005 also ended when a floating ice tongue formed and readvanced over the 2005/06 winter. These seasonal retreat/advance cycles may therefore be important for understanding Helheim's long-term behavior.

Circulation in the Ecologically Protected Lau Basin

NASA Astrophysics Data System (ADS)

Simons, E.; Speer, K. G.; Weijer, W.

2016-12-01

The Lau Basin, located in the South Pacific, north of New Zealand and East of Fiji, is a back-arc basin with active hydrothermal vents and volcanoes. In September 2015, the New Zealand Ministry for the Environment announced the new Kermadec Ocean Sanctuary in the southern portion of the basin. The sanctuary, which covers more than 620,000 square kilometers, is the world's largest protected marine environment boasting endangered species from turtles, whales, and seabirds to corals, shellfish, and zooplankton. Though protections are in place for the ecological residents of the basin, little is known about the fluid circulation that permits such ecological diversity. Whitworth et al. (1999), explored the water-masses associated with the deep western boundary current (DWBC) in the Tonga-Kermadec Trench and found the trench to be a passageway for Circumpolar Deep Water (CDW) into the South Pacific. In this project, an analysis of Ridge 2000 Program floats and Argo floats show intrusion of water from the trench into the basin, potentially providing another pathway of CDW into the western edge of the South Pacific. Using a simple model developed by Stommel-Arons (1960) and expanded upon by Pedlosky (1989) for abyssal circulation, the bulk of the flow pattern observed from the floats is qualitatively described, including the well-defined DWBC, first observed in this data, along the Lau-Fiji ridge.

Next generation sensing platforms for extended deployments in large-scale, multidisciplinary, adaptive sampling and observational networks

NASA Astrophysics Data System (ADS)

Cross, J. N.; Meinig, C.; Mordy, C. W.; Lawrence-Slavas, N.; Cokelet, E. D.; Jenkins, R.; Tabisola, H. M.; Stabeno, P. J.

2016-12-01

New autonomous sensors have dramatically increased the resolution and accuracy of oceanographic data collection, enabling rapid sampling over extremely fine scales. Innovative new autonomous platofrms like floats, gliders, drones, and crawling moorings leverage the full potential of these new sensors by extending spatiotemporal reach across varied environments. During 2015 and 2016, The Innovative Technology for Arctic Exploration Program at the Pacific Marine Environmental Laboratory tested several new types of fully autonomous platforms with increased speed, durability, and power and payload capacity designed to deliver cutting-edge ecosystem assessment sensors to remote or inaccessible environments. The Expendable Ice-Tracking (EXIT) gloat developed by the NOAA Pacific Marine Environmental Laboratory (PMEL) is moored near bottom during the ice-free season and released on an autonomous timer beneath the ice during the following winter. The float collects a rapid profile during ascent, and continues to collect critical, poorly-accessible under-ice data until melt, when data is transmitted via satellite. The autonomous Oculus sub-surface glider developed by the University of Washington and PMEL has a large power and payload capacity and an enhanced buoyancy engine. This 'coastal truck' is designed for the rapid water column ascent required by optical imaging systems. The Saildrone is a solar and wind powered ocean unmanned surface vessel (USV) developed by Saildrone, Inc. in partnership with PMEL. This large-payload (200 lbs), fast (1-7 kts), durable (46 kts winds) platform was equipped with 15 sensors designed for ecosystem assessment during 2016, including passive and active acoustic systems specially redesigned for autonomous vehicle deployments. The senors deployed on these platforms achieved rigorous accuracy and precision standards. These innovative platforms provide new sampling capabilities and cost efficiencies in high-resolution sensor deployment, including reconnaissance for annual fisheries and marine mammal surveys; better linkages between sustained observing platforms; and adaptive deployments that can easily target anomalies as they arise.

Marine Accident Report -- Ramming of the Poplar Street Bridge by the Towboat M/V City of Greenville and Its Four-Barge Tow, St. Louis, Missouri, April 2, 1983

DTIC Science & Technology

1983-11-29

floated downriver. One barge sank about 1 mile from the bridge, a second barge collided with barges moored at a chemical barge loading facility, and...about 1 mile from the bridge, a second barge collided with barges moored at a Monsanto Chemical Company barge loading facility, and the other barge...Poplar Street bridge along the Illinois side of the river. One or two of the breakaway barges collided with barges moored at a Monsanto Chemical

Isolation and culture of corneal cells and their interactions with dissociated trigeminal neurons.

PubMed

Chan, K Y; Haschke, R H

1982-08-01

The three cell types of rabbit cornea (epithelium, stromal fibroblasts and endothelium) were isolated by an improved method using both microdissection and selective enzyme treatment. This technique reproducibly resulted in an almost total recovery of each cell type from a given cornea. When maintained in culture, the three cell types showed different morphologic characteristics, each resembling the in vivo counterpart. The epithelial culture consisted of both attached and floating cells. The attached cells located at the marginal area of a colony were irregular in shape and possessed pseudopodia, while those in the confluent area were polygonal. Floating cells were typically vacuolated, curve-shaped and joined in groups of 2-4 cells as a spherical body enclosing a lucent interior. Comparison of mitotic rates, ultrastructure, keratin levels and other cytologic evidence suggested that the attached cells may correspond to the basal cells and less differentiated wing cells, while the floating cells may be analogous to the more differentiated wing cells and superficial cells. Neurons dissociated from neonatal rabbit trigeminal (Gasserian) ganglia were plated into multiwells partially covered with a given corneal cell type. The percentages of viable and neurite-bearing neurons were evaluated on the first three days. When neurons were grown in contact with each of the corneal cell types, neurites were extended in every case. However, when neurons were not in contact with the corneal cells in the coculture, only epithelial cells permitted neurite outgrowth. The data suggested two types of cellular interactions between corneal cells and sensory neurons, one of which may be the specific release of a neuronotrophic factor by epithelial cells. This culture system represents the first step towards developing an in vitro model for studying various cornea-trigeminal interactions.

Development of novel gastroretentive floating particulate drug delivery system of gliclazide.

PubMed

Awasthi, Rajendra; Kulkarni, Giriraj T

2012-09-01

The objective of present project was to improve the dissolution profile of gliclazide by developing floating alginate beads using various biodegradable polymers like gelatin, pectin and hydroxypropylmethylcellulose (HPMC). The floating beads were prepared by a simple ionotropic gelatin method using calcium carbonate as gas generating agent. The developed beads were characterized by Fourier transform infrared spectroscopy analysis, differential scanning calorimetry, X-ray diffraction analysis and scanning electron microscopy (SEM). The prepared beads showed good in vitro floatation, which was dependent on the concentration of gas-forming agent. SEM photomicrographs confirmed that the developed beads were spherical in shape and had particle size in the range of 730 to 890 μm. The incorporation efficiency was found to be in the range of 59.96 to 85.1%. The cumulative percent drug release from the beads after 10 h dissolution study at pH 1.2 and pH 5.8 was in the range of 33 to 46% and 82 to 95% respectively. The concentration of the gas generating agent was found to influence the release rate. The mechanism of drug release was Fickian diffusion with swelling. The in vivo sub-acute hypoglycemic study in high fat diet induced diabetic C57BL/6J mice demonstrated significant (p < 0.05) hypoglycemic effect over a period of 12 h and 24 h, respectively, with HPMC and pectin beads. A significant (p & 0.05) reduction in fasting and non-fasting blood glucose levels, reduction in fasting plasma insulin level and a significant improvement in glucose tolerance were observed in animals treated with formulations. The developed beads were suitable carriers for improving the systemic absorption of gliclazide and maintaining reduced blood glucose levels.

Widespread detection of a brominated flame retardant, hexabromocyclododecane, in expanded polystyrene marine debris and microplastics from South Korea and the Asia-Pacific coastal region.

PubMed

Jang, Mi; Shim, Won Joon; Han, Gi Myung; Rani, Manviri; Song, Young Kyoung; Hong, Sang Hee

2017-12-01

The role of marine plastic debris and microplastics as a carrier of hazardous chemicals in the marine environment is an emerging issue. This study investigated expanded polystyrene (EPS, commonly known as styrofoam) debris, which is a common marine debris item worldwide, and its additive chemical, hexabromocyclododecane (HBCD). To obtain a better understanding of chemical dispersion via EPS pollution in the marine environment, intensive monitoring of HBCD levels in EPS debris and microplastics was conducted in South Korea, where EPS is the predominant marine debris originate mainly from fishing and aquaculture buoys. At the same time, EPS debris were collected from 12 other countries in the Asia-Pacific region, and HBCD concentrations were measured. HBCD was detected extensively in EPS buoy debris and EPS microplastics stranded along the Korean coasts, which might be related to the detection of a quantity of HBCD in non-flame-retardant EPS bead (raw material). The wide detection of the flame retardant in sea-floating buoys, and the recycling of high-HBCD-containing EPS waste inside large buoys highlight the need for proper guidelines for the production and use of EPS raw materials, and the recycling of EPS waste. HBCD was also abundantly detected in EPS debris collected from the Asia-Pacific coastal region, indicating that HBCD contamination via EPS debris is a common environmental issue worldwide. Suspected tsunami debris from Alaskan beaches indicated that EPS debris has the potential for long-range transport in the ocean, accompanying the movement of hazardous chemicals. The results of this study indicate that EPS debris can be a source of HBCD in marine environments and marine food web. Copyright © 2017 Elsevier Ltd. All rights reserved.

Formation of a cavitation cluster in the vicinity of a quasi-empty rupture

NASA Astrophysics Data System (ADS)

Bol'shakova, E. S.; Kedrinskiy, V. K.

2017-09-01

The presentation deals with one of the experimental and numerical models of a quasi-empty rupture in the magma melt. This rupture is formed in the liquid layer of a distilled cavitating fluid under shock loading within the framework of the problem formulation with a small electromagnetic hydrodynamic shock tube. It is demonstrated that the rupture is shaped as a spherical segment, which retains its topology during the entire process of its evolution and collapsing. The dynamic behavior of the quasi-empty rupture is analyzed, and the growth of cavitating nuclei in the form of the boundary layer near the entire rupture interface is found. It is shown that rupture implosion is accompanied by the transformation of the bubble boundary layer to a cavitating cluster, which takes the form of a ring-shaped vortex floating upward to the free surface of the liquid layer. A p-κ mathematical model is formulated, and calculations are performed to investigate the implosion of a quasi-empty spherical cavity in the cavitating liquid, generation of a shock wave by this cavity, and dynamics of the bubble density growth in the cavitating cluster by five orders of magnitude.

Research on strategy marine noise map based on i4ocean platform: Constructing flow and key approach

NASA Astrophysics Data System (ADS)

Huang, Baoxiang; Chen, Ge; Han, Yong

2016-02-01

Noise level in a marine environment has raised extensive concern in the scientific community. The research is carried out on i4Ocean platform following the process of ocean noise model integrating, noise data extracting, processing, visualizing, and interpreting, ocean noise map constructing and publishing. For the convenience of numerical computation, based on the characteristics of ocean noise field, a hybrid model related to spatial locations is suggested in the propagation model. The normal mode method K/I model is used for far field and ray method CANARY model is used for near field. Visualizing marine ambient noise data is critical to understanding and predicting marine noise for relevant decision making. Marine noise map can be constructed on virtual ocean scene. The systematic marine noise visualization framework includes preprocessing, coordinate transformation interpolation, and rendering. The simulation of ocean noise depends on realistic surface. Then the dynamic water simulation gird was improved with GPU fusion to achieve seamless combination with the visualization result of ocean noise. At the same time, the profile and spherical visualization include space, and time dimensionality were also provided for the vertical field characteristics of ocean ambient noise. Finally, marine noise map can be published with grid pre-processing and multistage cache technology to better serve the public.

Preparation and optimization of glyceryl behenate-based highly porous pellets containing cilostazol.

PubMed

Hwang, Kyu-Mok; Byun, Woojin; Cho, Cheol-Hee; Park, Eun-Seok

2018-06-01

The aim of this study was to prepare a highly porous multiparticulate dosage form containing cilostazol for gastroretentive drug delivery. The floating pellets were prepared with glyceryl behenate as a matrix former and camphor as a sublimating agent by extrusion/spheronization and sublimation under vacuum. Granules prepared with sublimation at 60 °C displayed a slower dissolution rate and smoother surface morphology than those prepared at lower temperatures. This was unexpected as the reported melting point of glyceryl behenate is higher than 69 °C. The DSC study revealed that melting began at a lower temperature owing to the multicomponent property of glyceryl behenate, which led to a sintering effect. The prepared pellets were spherical with unimodal size distribution. They also had porous structures with increased porosity, which led to immediate buoyancy. As cilostazol is a hydrophobic drug that has an erosion-based release mechanism, drug release profile was highly correlated with the percentage of disintegrated pellets. Various excipients were added to the glyceryl behenate-based formulation to increase the floating duration. When hydroxyethyl cellulose was added to the glyceryl behenate-based pellets, acceptable dissolution rate and buoyancy were acquired. This system could potentially be used for gastroretentive delivery of various hydrophobic drugs, which was generally considered difficult.

On ice rifts and the stability of non-Newtonian extensional flows on a sphere

NASA Astrophysics Data System (ADS)

Sayag, Roiy

2017-11-01

Rifts that form at the fronts of floating ice shelves that spread into the ocean can trigger major calving events in the ice. The deformation of ice can be modeled as a thin viscous film driven by buoyancy. The front of such a viscous film that propagates over a flat surface with no-slip basal conditions is known to have stable axisymmetric solutions. In contrast, when the fluid propagates under free-slip conditions at the substrate, the front can become unstable to small perturbations if the fluid is sufficiently strain-rate softening. Consequently, the front will develop tongues with a characteristic wavelength that coarsens over time, a pattern that is reminiscent of ice rifts. Here we investigate the stability of a spherical sheet of power-law fluids under free-slip basal conditions. The fluid is discharged at constant flux and axisymmetrically with respect to the pole, and propagates towards the equator. The propagating front in such a situation may become unstable due to its failure to sustain large extensional forces, resulting in the formation of rifts. This study has implications to understanding the cause of patterns that are observed on shells of floating ice in a range of planetary objects, and whether open rifts that sustain life were feasible in snowball earth. Israel Science Foundation 1368/16.

Correlation between apical protrusion in the Scheimflug imaging and Corneal Hysteresis and Corneal Resistance factor by Ocular Response Analyzer, among refractive non-keratoconic Egyptian patients.

PubMed

Refai, Tamer Adel

2015-10-01

Apical protrusion in the central 4-mm ring in the Scheimflug imaging (Pentacam), both for the anterior and posterior floats as well as Corneal Hysteresis and Corneal Resistance Factor by Ocular Response Analyzer (ORA), generally are considered important predictors for post-Lasik ectasia. The aim of this work was to find out if there is a statistically significant correlation between these different predictors and their correlation with the central corneal thickness for refractive non-keratoconic Egyptian patients trying to achieve a better decision and avoiding ectasia. This case-control study involved 142 eyes (of 77 patients with various refractive errors) arriving at the refractive surgery unit in the Research Institute of Ophthalmology in Giza (Egypt) in 2014-2015 seeking excimer laser ablation. The flattest, steepest keratometry readings, central corneal thickness as well as the apical protrusion in the central 4-mm ring, both for the anterior and posterior floats, in microns were measured by Scheimflug imaging. The Corneal Hysteresis and Corneal Resistance Factor were measured by the ocular response analyzer. Statistical analysis was performed by SPSS, using the Pearson correlation test. The spherical refractive error ranged from +7.00 to -13.00 diopters (-3.80 ± 2.89). The central pachymetry ranged from 494 to 634 μm (550.35 ± 32.13). For the central 4-mm ring, the apical protrusion ranged from 0 to +15 μ (6.93 ± 2.99) for the anterior float and from -3 to +20 μ (9.33 ± 4.55) for the posterior float. The Corneal Hysterisis (CH) ranged from 7 to 14.8 mmHg (10.18±1.44), while the Corneal Resistance Factor (CRF) ranged from 7.5 to 14.9 mmHg (10.58 ± 1.67). There was a strong positive correlation between the central corneal thickness and both Corneal Hysteresis (CH: r = 0.56, P ≤ 0.01) and Corneal Resistance Factor (r = 0.46, P ≤ 0.01). A significant correlation (P < 0.05, r = 0.15) existed between apical protrusion in the posterior float and the central corneal thickness. Also, significant negative correlation (P < 0.05, r = -0.12) existed between apical protrusion in the anterior float by pentacam and the Corneal Resistance Factor by ocular response analyzer. Our finding of a strong positive correlation between both Corneal Hysteresis and Corneal Resistance Factor and the Central corneal thickness being important for biomechanical corneal stability. The findings of this study also support using both machines preoperatively to decrease the risk of post-Lasik ectasia.

Hydrogen production from salt water by Marine blue green algae and solar radiation

NASA Technical Reports Server (NTRS)

Mitsui, A.; Rosner, D.; Kumazawa, S.; Barciela, S.; Phlips, E.

1985-01-01

Two marine bluegreen algae, Oscillatoria sp. Miami BG 7 and Synechococcus sp Miami 041511 have been selected as the result of over 10 years continuous and intensive effort of isolation, growth examination, and the screening of hydrogen photoproduction capability in this laboratory. Both strains photoproduced hydrogen for several days at high rates and a quantity of hydrogen was accumulated in a closed vessel. Overall hydrogen donor substance of the hydrogen photoproduction was found to be salt water. Using strain Miami BG 7, a two step method of hydrogen photoproduction from salt water was successfully developed and this was recycled several times over a one month period using both free cells and immobilized cells in both indoor and outdoor under natural sunlight. According to these experiments, a prototype floating hydrogen production system was designed for further development of the biosolar hydrogen production system.

Viscous grounding lines

NASA Astrophysics Data System (ADS)

Worster, Grae; Huppert, Herbert; Robison, Rosalyn; Nandkishore, Rahul; Rajah, Luke

2008-11-01

We have used simple laboratory experiments with viscous fluids to explore the dynamics of grounding lines between Antarctic marine ice sheets and the freely floating ice shelves into which they develop. Ice sheets are shear-dominated gravity currents, while ice shelves are extensional gravity currents with zero shear to leading order. Though ice sheets have non-Newtonian rheology, fundamental aspects of their flow can be explored using Newtonian fluid mechanics. We have derived a mathematical model of this flow that incorporates a new dynamic boundary condition for the position of the grounding line, where the gravity current loses contact with the solid base. Good agreement between our theoretical predictions and our experimental measurements, made using gravity currents of syrup flowing down a rigid slope into a deep, dense salt solution, gives confidence in the fundamental assumptions of our model, which can be incorporated into shallow-ice models to make important predictions regarding the dynamical stability of marine ice sheets.

Representing grounding line migration in synchronous coupling between a marine ice sheet model and a z-coordinate ocean model

NASA Astrophysics Data System (ADS)

Goldberg, D. N.; Snow, K.; Holland, P.; Jordan, J. R.; Campin, J.-M.; Heimbach, P.; Arthern, R.; Jenkins, A.

2018-05-01

Synchronous coupling is developed between an ice sheet model and a z-coordinate ocean model (the MITgcm). A previously-developed scheme to allow continuous vertical movement of the ice-ocean interface of a floating ice shelf ("vertical coupling") is built upon to allow continuous movement of the grounding line, or point of floatation of the ice sheet ("horizontal coupling"). Horizontal coupling is implemented through the maintenance of a thin layer of ocean ( ∼ 1 m) under grounded ice, which is inflated into the real ocean as the ice ungrounds. This is accomplished through a modification of the ocean model's nonlinear free surface evolution in a manner akin to a hydrological model in the presence of steep bathymetry. The coupled model is applied to a number of idealized geometries and shown to successfully represent ocean-forced marine ice sheet retreat while maintaining a continuous ocean circulation.

Plastic in the Thames: a river runs through it.

PubMed

Morritt, David; Stefanoudis, Paris V; Pearce, Dave; Crimmen, Oliver A; Clark, Paul F

2014-01-15

Although contamination of the marine ecosystems by plastics is becoming recognised as a serious pollution problem, there are few studies that demonstrate the contribution made by freshwater catchments. Over a three month period from September to December 2012, at seven localities in the upper Thames estuary, 8490 submerged plastic items were intercepted in eel fyke nets anchored to the river bed. Whilst there were significant differences in the numbers of items at these locations, the majority were some type of plastic. Additionally in excess of 20% of the litter items were components of sanitary products. The most contaminated sites were in the vicinity of sewage treatment works. While floating litter is visible, this study also demonstrates that a large unseen volume of submerged plastic is flowing into the marine environment. It is therefore important that this sub-surface component is considered when assessing plastic pollution input into the sea. Copyright © 2013 Elsevier Ltd. All rights reserved.

Magnetic light cloaking control in the marine planktonic copepod Sapphirina

NASA Astrophysics Data System (ADS)

Kashiwagi, H.; Mizukawa, Y.; Iwasaka, M.; Ohtsuka, S.

2017-05-01

We investigated the light cloaking behavior of the marine planktonic copepod Sapphirina under a magnetic field. Optical interferences in the multi-laminated guanine crystal layer beneath the dorsal body surface create a brilliant structural color, which can be almost entirely removed by changing the light reflection. In the investigation, we immersed segments of Sapphirina in seawater contained in an optical chamber. When the derived Sapphirina segments were attached to the container surface, they were inert to magnetic fields up to 300 mT. However, when the back plate segments were attached to the substrate at a point, with most of the plate floating in the seawater, the plate rotated oppositely to the applied magnetic field. In addition, the brilliant parts of the Sapphirina back plate rotated backward and forward by changing the magnetic field directions. Our experiment suggests a new model of an optical micro-electro-mechanical system that is controllable by magnetic fields.

Characterisation of the biofouling community on a floating wave energy device.

PubMed

Nall, Christopher R; Schläppy, Marie-Lise; Guerin, Andrew J

2017-05-01

Wave energy devices are novel structures in the marine environment and, as such, provide a unique habitat for biofouling organisms. In this study, destructive scrape samples and photoquadrats were used to characterise the temperate epibenthic community present on prototypes of the Pelamis wave energy converter. The biofouling observed was extensive and diverse with 115 taxa recorded including four non-native species. Vertical zonation was identified on the sides of the device, with an algae-dominated shallow subtidal area and a deeper area characterised by a high proportion of suspension-feeding invertebrates. Differences in species composition and biomass were also observed between devices, along the length of the device and between sampling dates. This research provides an insight into the variation of biofouling assemblages on a wave energy device as well as the potential technical and ecological implications associated with biofouling on marine renewable energy structures.

Phytoplankton bloom off Iceland

NASA Image and Video Library

2014-08-13

A massive phytoplankton bloom stained the waters of the Atlantic Ocean north of Iceland with brilliant jewel tones in late summer, 2014. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Aqua satellite captured this true-color image on August 2. Huge colonies of the floating, plant-like organisms create swirls of green, teal and turquoise and cover over 80% of the visible ocean off the northeast coast of Iceland. Marine phytoplankton require just the right amount of sunlight, dissolved nutrients and water temperatures which are not too hot, nor too cold to spark explosive reproduction and result in blooms which can cover hundreds of square kilometers. Phytoplankton form the base of the marine food chain, and are a rich food source for zooplankton, fish and other marine species. Some species, however, can deplete the water of oxygen and may become toxic to marine life. Credit: NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team 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

Challenges and potential solutions for European coastal ocean modelling

NASA Astrophysics Data System (ADS)

She, Jun; Stanev, Emil

2017-04-01

Coastal operational oceanography is a science and technological platform to integrate and transform the outcomes in marine monitoring, new knowledge generation and innovative technologies into operational information products and services in the coastal ocean. It has been identified as one of the four research priorities by EuroGOOS (She et al. 2016). Coastal modelling plays a central role in such an integration and transformation. A next generation coastal ocean forecasting system should have following features: i) being able to fully exploit benefits from future observations, ii) generate meaningful products in finer scales e.g., sub-mesoscale and in estuary-coast-sea continuum, iii) efficient parallel computing and model grid structure, iv) provide high quality forecasts as forcing to NWP and coastal climate models, v) resolving correctly inter-basin and inter-sub-basin water exchange, vi) resolving synoptic variability and predictability in marine ecosystems, e.g., for algae bloom, vi) being able to address critical and relevant issues in coastal applications, e.g., marine spatial planning, maritime safety, marine pollution protection, disaster prevention, offshore wind energy, climate change adaptation and mitigation, ICZM (integrated coastal zone management), the WFD (Water Framework Directive), and the MSFD (Marine Strategy Framework Directive), especially on habitat, eutrophication, and hydrographic condition descriptors. This presentation will address above challenges, identify limits of current models and propose correspondent research needed. The proposed roadmap will address an integrated monitoring-modelling approach and developing Unified European Coastal Ocean Models. In the coming years, a few new developments in European Sea observations can expected, e.g., more near real time delivering on profile observations made by research vessels, more shallow water Argo floats and bio-Argo floats deployed, much more high resolution sea level data from SWOT and on-going altimetry missions, contributing to resolving (sub-)mesoscale eddies, more currents measurements from ADCPs and HF radars, geostationary data for suspended sediment and diurnal observations from satellite SST products. These developments will make it possible to generate new knowledge and build up new capacities for modelling and forecasting systems, e.g., improved currents forecast, improved water skin temperature and surface winds forecast, improved modelling and forecast of (sub) mesoscale activities and drift forecast, new forecast capabilities on SPM (Suspended Particle Matter) and algae bloom. There will be much more in-situ and satellite data available for assimilation. The assimilation of sea level, chl-a, ferrybox and profile observations will greatly improves the ocean-ice-ecosystem forecast quality.

Ocean Tide Influences on the Antarctic and Greenland Ice Sheets

NASA Astrophysics Data System (ADS)

Padman, Laurie; Siegfried, Matthew R.; Fricker, Helen A.

2018-03-01

Ocean tides are the main source of high-frequency variability in the vertical and horizontal motion of ice sheets near their marine margins. Floating ice shelves, which occupy about three quarters of the perimeter of Antarctica and the termini of four outlet glaciers in northern Greenland, rise and fall in synchrony with the ocean tide. Lateral motion of floating and grounded portions of ice sheets near their marine margins can also include a tidal component. These tide-induced signals provide insight into the processes by which the oceans can affect ice sheet mass balance and dynamics. In this review, we summarize in situ and satellite-based measurements of the tidal response of ice shelves and grounded ice, and spatial variability of ocean tide heights and currents around the ice sheets. We review sensitivity of tide heights and currents as ocean geometry responds to variations in sea level, ice shelf thickness, and ice sheet mass and extent. We then describe coupled ice-ocean models and analytical glacier models that quantify the effect of ocean tides on lower-frequency ice sheet mass loss and motion. We suggest new observations and model developments to improve the representation of tides in coupled models that are used to predict future ice sheet mass loss and the associated contribution to sea level change. The most critical need is for new data to improve maps of bathymetry, ice shelf draft, spatial variability of the drag coefficient at the ice-ocean interface, and higher-resolution models with improved representation of tidal energy sinks.

A global, high-resolution data set of ice sheet topography, cavity geometry, and ocean bathymetry

NASA Astrophysics Data System (ADS)

Schaffer, Janin; Timmermann, Ralph; Arndt, Jan Erik; Savstrup Kristensen, Steen; Mayer, Christoph; Morlighem, Mathieu; Steinhage, Daniel

2016-10-01

The ocean plays an important role in modulating the mass balance of the polar ice sheets by interacting with the ice shelves in Antarctica and with the marine-terminating outlet glaciers in Greenland. Given that the flux of warm water onto the continental shelf and into the sub-ice cavities is steered by complex bathymetry, a detailed topography data set is an essential ingredient for models that address ice-ocean interaction. We followed the spirit of the global RTopo-1 data set and compiled consistent maps of global ocean bathymetry, upper and lower ice surface topographies, and global surface height on a spherical grid with now 30 arcsec grid spacing. For this new data set, called RTopo-2, we used the General Bathymetric Chart of the Oceans (GEBCO_2014) as the backbone and added the International Bathymetric Chart of the Arctic Ocean version 3 (IBCAOv3) and the International Bathymetric Chart of the Southern Ocean (IBCSO) version 1. While RTopo-1 primarily aimed at a good and consistent representation of the Antarctic ice sheet, ice shelves, and sub-ice cavities, RTopo-2 now also contains ice topographies of the Greenland ice sheet and outlet glaciers. In particular, we aimed at a good representation of the fjord and shelf bathymetry surrounding the Greenland continent. We modified data from earlier gridded products in the areas of Petermann Glacier, Hagen Bræ, and Sermilik Fjord, assuming that sub-ice and fjord bathymetries roughly follow plausible Last Glacial Maximum ice flow patterns. For the continental shelf off Northeast Greenland and the floating ice tongue of Nioghalvfjerdsfjorden Glacier at about 79° N, we incorporated a high-resolution digital bathymetry model considering original multibeam survey data for the region. Radar data for surface topographies of the floating ice tongues of Nioghalvfjerdsfjorden Glacier and Zachariæ Isstrøm have been obtained from the data centres of Technical University of Denmark (DTU), Operation Icebridge (NASA/NSF), and Alfred Wegener Institute (AWI). For the Antarctic ice sheet/ice shelves, RTopo-2 largely relies on the Bedmap-2 product but applies corrections for the geometry of Getz, Abbot, and Fimbul ice shelf cavities. The data set is available in full and in regional subsets in NetCDF format from the PANGAEA database at doi:10.1594/PANGAEA.856844.

Litter survey detects the South Atlantic 'garbage patch'.

PubMed

Ryan, Peter G

2014-02-15

A distance-based technique was used to assess the distribution and abundance of floating marine debris (>1cm) in the southeast Atlantic Ocean between Cape Town and Tristan da Cunha, crossing the southern edge of the South Atlantic 'garbage patch' predicted by surface drift models. Most litter was made of plastic (97%). Detection distances were influenced by the size and buoyancy of litter items. Litter density decreased from coastal waters off Cape Town (>100 items km(-2)) to oceanic waters (<10 items km(-2)), and was consistently higher (6.2 ± 1.3 items km(-2)) from 3 to 8°E than in adjacent oceanic waters (2.7 ± 0.3 items km(-2)) or in the central South Atlantic around Tristan (1.0 ± 0.4 items km(-2)). The area with high litter density had few seaweeds, suggesting that most litter had been drifting for a long time. The results indicate that floating debris is accumulating in the South Atlantic gyre as far south as 34-35°S. Copyright © 2013 Elsevier Ltd. All rights reserved.

Plastic Accumulation in the Mediterranean Sea

PubMed Central

Cózar, Andrés; Sanz-Martín, Marina; Martí, Elisa; González-Gordillo, J. Ignacio; Ubeda, Bárbara; Gálvez, José Á.; Irigoien, Xabier; Duarte, Carlos M.

2015-01-01

Concentrations of floating plastic were measured throughout the Mediterranean Sea to assess whether this basin can be regarded as a great accumulation region of plastic debris. We found that the average density of plastic (1 item per 4 m2), as well as its frequency of occurrence (100% of the sites sampled), are comparable to the accumulation zones described for the five subtropical ocean gyres. Plastic debris in the Mediterranean surface waters was dominated by millimeter-sized fragments, but showed a higher proportion of large plastic objects than that present in oceanic gyres, reflecting the closer connection with pollution sources. The accumulation of floating plastic in the Mediterranean Sea (between 1,000 and 3,000 tons) is likely related to the high human pressure together with the hydrodynamics of this semi-enclosed basin, with outflow mainly occurring through a deep water layer. Given the biological richness and concentration of economic activities in the Mediterranean Sea, the affects of plastic pollution on marine and human life are expected to be particularly frequent in this plastic accumulation region. PMID:25831129

Pollutants in Plastics within the North Pacific Subtropical Gyre.

PubMed

Chen, Qiqing; Reisser, Julia; Cunsolo, Serena; Kwadijk, Christiaan; Kotterman, Michiel; Proietti, Maira; Slat, Boyan; Ferrari, Francesco F; Schwarz, Anna; Levivier, Aurore; Yin, Daqiang; Hollert, Henner; Koelmans, Albert A

2018-01-16

Here we report concentrations of pollutants in floating plastics from the North Pacific accumulation zone (NPAC). We compared chemical concentrations in plastics of different types and sizes, assessed ocean plastic potential risks using sediment quality criteria, and discussed the implications of our findings for bioaccumulation. Our results suggest that at least a fraction of the NPAC plastics is not in equilibrium with the surrounding seawater. For instance, "hard plastic" samples had significantly higher PBDE concentrations than "nets and ropes" samples, and 29% of them had PBDE composition similar to a widely used flame-retardant mixture. Our findings indicate that NPAC plastics may pose a chemical risk to organisms as 84% of the samples had at least one chemical exceeding sediment threshold effect levels. Furthermore, our surface trawls collected more plastic than biomass (180 times on average), indicating that some NPAC organisms feeding upon floating particles may have plastic as a major component of their diets. If gradients for pollutant transfer from NPAC plastic to predators exist (as indicated by our fugacity ratio calculations), plastics may play a role in transferring chemicals to certain marine organisms.

Proteomic characterization of the outer membrane vesicle of the halophilic marine bacterium Novosphingobium pentaromativorans US6-1.

PubMed

Yun, Sung Ho; Lee, Sang-Yeop; Choi, Chi-Won; Lee, Hayoung; Ro, Hyun-Joo; Jun, Sangmi; Kwon, Yong Min; Kwon, Kae Kyoung; Kim, Sang-Jin; Kim, Gun-Hwa; Kim, Seung Il

2017-01-01

Novosphingobium pentaromativorans US6-1 is a Gram-negative halophilic marine bacterium able to utilize several polycyclic aromatic hydrocarbons such as phenanthrene, pyrene, and benzo[a]pyrene. In this study, using transmission electron microscopy, we confirmed that N. pentaromativorans US6-1 produces outer membrane vesicles (OMVs). N. pentaromativorans OMVs (hereafter OMV Novo ) are spherical in shape, and the average diameter of OMV Novo is 25-70 nm. Proteomic analysis revealed that outer membrane proteins and periplasmic proteins of N. pentaromativorans are the major protein components of OMV Novo . Comparative proteomic analysis with the membrane-associated protein fraction and correlation analysis demonstrated that the outer membrane proteins of OMV Novo originated from the membrane- associated protein fraction. To the best of our knowledge, this study is the first to characterize OMV purified from halophilic marine bacteria.

Workshop and Conference on Clay Microstructure: The Microstructure of Fine-Grained Terrigenous Marine Sediments - From Muds to Shale Held in Stennis, Mississippi on October 4-7, 1988

DTIC Science & Technology

1988-10-07

from experiments on wet clay minerals by using the EC technique.(3,4) Layer lattice image of fully hydrated tubular halloysite could be clearly observed...in wet air environment. Tubular and spherical halloysite and their hydrazine complexes were observed both in wet air and in vacuum, and their

U.S. Marine Corps Level-Dependent Hearing Protector Assessment: Objective Measures of Hearing Protection Devices

DTIC Science & Technology

2014-01-01

12 4.2.1 Loudspeaker Array ...Instrumentation 4.2.1 Loudspeaker Array Target stimuli were presented from a spherical loudspeaker array consisting of 57 Meyer Sound MM-4XP miniature... loudspeaker array on a raised platform that placed their ears at the same elevation as the 0° loudspeaker ring. The chair was free to rotate 360° and

Light Scattering by Marine Particles: Modeling with Non-Spherical Shapes

DTIC Science & Technology

2011-04-15

scattering by nonspherical particles: application to coccoliths detached from Emiliania huxleyi. Limnology and Oceanography, 46. 1438— 1454,2001. H.R...application to coccoliths detached from Emiliania huxleyi," Limnol. Oceanogr. 46, 1438-1454 (2001). 5. H.R.Gordon, "Backscattering of light from...by coccoliths detached from Emiliania huxleyi," Applied Optics, 48, 6059-6073 (2009). Light scattering by coccoliths detached from Emiliania

Field Verification Program (Aquatic Disposal). Sister Chromatid Exchange in Marine Polychaetes Exposed to Black Rock Harbor Sediment.

DTIC Science & Technology

1985-07-01

the reservoi r Iones and were connected t - to (-. m capacit t itted wit ’ el on diaphragms. These pumps 4, . fI Stir ear Sigure . i-pended se(ti ret’t...phases served as the control. Each treatment had 15 worms. The worms were fed prawn flakes (ADT-Prime, Aquatic Diet Technology, Brooklyn, N. Y .) in a...counter - -- 4 relay o switch solenoid valve -- ani; seawater mnf~ water wtr trap "- lo -t chamber,t a I mix"n chamber float switch distribution *chamber

Biasing, acquisition, and interpretation of a dense Langmuir probe array in NSTX.

PubMed

Jaworski, M A; Kallman, J; Kaita, R; Kugel, H; LeBlanc, B; Marsala, R; Ruzic, D N

2010-10-01

A dense array of 99 Langmuir probes has been installed in the lower divertor region of the National Spherical Torus Experiment (NSTX). This array is instrumented with a system of electronics that allows flexibility in the choice of probes to bias as well as the type of measurement (including standard swept, single probe, triple probe, and operation as passive floating potential and scrape-off-layer SOL current monitors). The use of flush-mounted probes requires careful interpretation. The time dependent nature of the SOL makes swept-probe traces difficult to interpret. To overcome these challenges, the single- and triple-Langmuir probe signals are used in complementary fashion to determine the temperature and density at the probe location. A comparison to midplane measurements is made.

Sargassum horneri C. Agardh space capacity estimation reveals that thallus surface area varies with wet weight

PubMed Central

Sasa, Shuji; Komatsu, Teruhisa

2018-01-01

Sargassum horneri C. Agardh is an important commercial edible seaweed species in east Asia. Benthic beds and floating rafts in coastal areas make excellent habitats for marine organisms to feed, hide, and spawn. Many commercially important fish species such as Japanese anchovy (Engraulis japonicus), yellowtail (Seriola quinqueradiata), and Japanese horse mackerel (Trachurus japonicus) live in seaweed beds. Chinese and Japanese fisherman rely on S. horneri beds as productive fish harvest areas. The Zhejiang government in China set a total allowable catch standard, to preserve the Ma’an Islands ecosystem, which is a marine protected area. In this study we analysed the association between weight and one-sided surface area of S. horneri beds, and calculated the ratio of one-sided surface area to change in wet weight over time. We collected samples from December 2014 to May 2015. Approximately 1 g of S. horneri biomass provided ~15 cm2 of one-sided surface area available to marine organisms. These calculations can be used as a reference regarding potential space to improve total allowable catch standard management in S. horneri beds, through the estimation of space capacity of seaweed beds. PMID:29920534

Resolution Enhanced Magnetic Sensing System for Wide Coverage Real Time UXO Detection

NASA Astrophysics Data System (ADS)

Zalevsky, Zeev; Bregman, Yuri; Salomonski, Nizan; Zafrir, Hovav

2012-09-01

In this paper we present a new high resolution automatic detection algorithm based upon a Wavelet transform and then validate it in marine related experiments. The proposed approach allows obtaining an automatic detection in a very low signal to noise ratios. The amount of calculations is reduced, the magnetic trend is depressed and the probability of detection/ false alarm rate can easily be controlled. Moreover, the algorithm enables to distinguish between close targets. In the algorithm we use the physical dependence of the magnetic field of a magnetic dipole in order to define a Wavelet mother function that later on can detect magnetic targets modeled as dipoles and embedded in noisy surrounding, at improved resolution. The proposed algorithm was realized on synthesized targets and then validated in field experiments involving a marine surface-floating system for wide coverage real time unexploded ordinance (UXO) detection and mapping. The detection probability achieved in the marine experiment was above 90%. The horizontal radial error of most of the detected targets was only 16 m and two baseline targets that were immersed about 20 m one to another could easily be distinguished.

Three Campaigns to Image the Earth's Interior Using Mermaids (Mobile Earthquake Recorder in Marine Areas by Indepen-dent Divers).

NASA Astrophysics Data System (ADS)

Pazmino, A.; Bonnieux, S.; Joubert, C.; Gonzales, N.; Hello, Y.; Nolet, G.

2014-12-01

Mermaids have been developed to improve seismic data coverage in the oceanic domain for imaging of the Earth's interior. Though housed in conventional Argo-type floats, hardware and software was developed to analyze acoustic signals and determine whether an earthquake has been recorded, and whether the Mermaid should to come up to the surface and transmit to the satellite. In contrast to the passive Argo floats, Mermaids are essentially floating computers that decide for themselves what to do. After testing in the Mediterranean and Indian Ocean and improving the concept for more than a year, we recently started two fully scientific experiments using Mermaids. In cooperation with Inocar, we deployed a fleet of 10 Mermaids in May 2014 around the Galapagos islands from the LAE Sirius to study the suspected mantle plume beneath these islands. We are interested in plumes because we do not understand very well how the mantle has retained an almost constant temperature for three or four billion years, an essential condition for life to develop. The depth of mantle plumes is an important unknown, because it may tell us how well the lower mantle is able to transmit heat into the upper mantle. A second experiment is taking place in the Ligurian Sea. This basin opened with a rifting phase in late Oligocene. The rifting phase of the Ligurian basin is followed by the Corsica - Sardinia block counterclockwise rotation, but the deeper causes of this are still poorly understood. Three Mermaids are deployed, and re-deployed after drifting too far west, to augment the P arrivals observed for 6 months with 5 OBS's during the 2008 Grosmarin campaign. The experience obtained with this first generation of Mermaids has led to the development of a new multidisciplinary float (Multimermaid), which is programmable, able to carry up to 8 sensors to a depth of 3000 m, and with a duration of at least five years.

Light Scattering by Marine Particles: Modeling with Non-spherical Shapes

DTIC Science & Technology

2009-01-01

1491−1499, 1994. Gordon, H.R. and Tao Du, Light scattering by nonspherical particles: application to coccoliths detached from Emiliania huxleyi...from Emiliania huxleyi, Applied Optics, (2009). van de Hulst, H.C., 1957. Light Scattering by Small Particles, Wiley. Xu, Yu-lin, and Bo A.S...G.C. Boynton, Light scattering by coccoliths detached from Emiliania huxleyi, Applied Optics, (2009). [submitted, in revision] 6 m = 1.05

Light Scattering by Marine Particles: Modeling with Non-spherical Shapes

DTIC Science & Technology

2010-09-30

4271—4282 (1996). Gordon, H.R. and Tao Du, Light scattering by nonspherical particles: application to coccoliths detached from Emiliania huxleyi... Emiliania huxleyi, Applied Optics, (2009). PUBLICATIONS H.R. Gordon, T.J. Smyth, W.M. Balch, and G.C. Boynton, Light scattering by coccoliths...detached from Emiliania huxleyi, Applied Optics, 48, 6059–6073 (2009). [published, refereed] 5 H.R. Gordon, Some Reflections on 35 Years of

Light Scattering by Marine Particles: Modeling with Non-spherical Shapes

DTIC Science & Technology

2006-01-01

coccoliths detached from Emiliania huxleyi , Limnology and Oceanography, 46, 1438−1454, 2001. Gordon, H.R., Backscattering of light from disk-like...the backscattering by coccoliths detached from E. huxleyi ; however, they found that, while the resulting spectral variation of the backscattering...Prescribed by ANSI Std Z39-18 APPROACH I use detached coccoliths from the coccolithophorid E. huxleyi (Figure 1) as a case study for applying non

Aspergillus Sydowii Marine Fungal Bloom in Australian Coastal Waters, Its Metabolites and Potential Impact on Symbiodinium Dinoflagellates.

PubMed

Hayashi, Aiko; Crombie, Andrew; Lacey, Ernest; Richardson, Anthony J; Vuong, Daniel; Piggott, Andrew M; Hallegraeff, Gustaaf

2016-03-16

Dust has been widely recognised as an important source of nutrients in the marine environment and as a vector for transporting pathogenic microorganisms. Disturbingly, in the wake of a dust storm event along the eastern Australian coast line in 2009, the Continuous Plankton Recorder collected masses of fungal spores and mycelia (~150,000 spores/m³) forming a floating raft that covered a coastal area equivalent to 25 times the surface of England. Cultured A. sydowii strains exhibited varying metabolite profiles, but all produced sydonic acid, a chemotaxonomic marker for A. sydowii. The Australian marine fungal strains share major metabolites and display comparable metabolic diversity to Australian terrestrial strains and to strains pathogenic to Caribbean coral. Secondary colonisation of the rafts by other fungi, including strains of Cladosporium, Penicillium and other Aspergillus species with distinct secondary metabolite profiles, was also encountered. Our bioassays revealed that the dust-derived marine fungal extracts and known A. sydowii metabolites such as sydowic acid, sydowinol and sydowinin A adversely affect photophysiological performance (Fv/Fm) of the coral reef dinoflagellate endosymbiont Symbiodinium. Different Symbiodinium clades exhibited varying sensitivities, mimicking sensitivity to coral bleaching phenomena. The detection of such large amounts of A. sydowii following this dust storm event has potential implications for the health of coral environments such as the Great Barrier Reef.

Aspergillus Sydowii Marine Fungal Bloom in Australian Coastal Waters, Its Metabolites and Potential Impact on Symbiodinium Dinoflagellates

PubMed Central

Hayashi, Aiko; Crombie, Andrew; Lacey, Ernest; Richardson, Anthony J.; Vuong, Daniel; Piggott, Andrew M.; Hallegraeff, Gustaaf

2016-01-01

Dust has been widely recognised as an important source of nutrients in the marine environment and as a vector for transporting pathogenic microorganisms. Disturbingly, in the wake of a dust storm event along the eastern Australian coast line in 2009, the Continuous Plankton Recorder collected masses of fungal spores and mycelia (~150,000 spores/m3) forming a floating raft that covered a coastal area equivalent to 25 times the surface of England. Cultured A. sydowii strains exhibited varying metabolite profiles, but all produced sydonic acid, a chemotaxonomic marker for A. sydowii. The Australian marine fungal strains share major metabolites and display comparable metabolic diversity to Australian terrestrial strains and to strains pathogenic to Caribbean coral. Secondary colonisation of the rafts by other fungi, including strains of Cladosporium, Penicillium and other Aspergillus species with distinct secondary metabolite profiles, was also encountered. Our bioassays revealed that the dust-derived marine fungal extracts and known A. sydowii metabolites such as sydowic acid, sydowinol and sydowinin A adversely affect photophysiological performance (Fv/Fm) of the coral reef dinoflagellate endosymbiont Symbiodinium. Different Symbiodinium clades exhibited varying sensitivities, mimicking sensitivity to coral bleaching phenomena. The detection of such large amounts of A. sydowii following this dust storm event has potential implications for the health of coral environments such as the Great Barrier Reef. PMID:26999164

Modeling marine surface microplastic transport to assess optimal removal locations

NASA Astrophysics Data System (ADS)

Sherman, Peter; van Sebille, Erik

2016-01-01

Marine plastic pollution is an ever-increasing problem that demands immediate mitigation and reduction plans. Here, a model based on satellite-tracked buoy observations and scaled to a large data set of observations on microplastic from surface trawls was used to simulate the transport of plastics floating on the ocean surface from 2015 to 2025, with the goal to assess the optimal marine microplastic removal locations for two scenarios: removing the most surface microplastic and reducing the impact on ecosystems, using plankton growth as a proxy. The simulations show that the optimal removal locations are primarily located off the coast of China and in the Indonesian Archipelago for both scenarios. Our estimates show that 31% of the modeled microplastic mass can be removed by 2025 using 29 plastic collectors operating at a 45% capture efficiency from these locations, compared to only 17% when the 29 plastic collectors are moored in the North Pacific garbage patch, between Hawaii and California. The overlap of ocean surface microplastics and phytoplankton growth can be reduced by 46% at our proposed locations, while sinks in the North Pacific can only reduce the overlap by 14%. These results are an indication that oceanic plastic removal might be more effective in removing a greater microplastic mass and in reducing potential harm to marine life when closer to shore than inside the plastic accumulation zones in the centers of the gyres.

Assessing the effects of ultraviolet radiation on the photosynthetic potential in Archean marine environments

NASA Astrophysics Data System (ADS)

Avila-Alonso, Dailé; Baetens, Jan M.; Cardenas, Rolando; de Baets, Bernard

2017-07-01

In this work, the photosynthesis model presented by Avila et al. in 2013 is extended and more scenarios inhabited by ancient cyanobacteria are investigated to quantify the effects of ultraviolet (UV) radiation on their photosynthetic potential in marine environments of the Archean eon. We consider ferrous ions as blockers of UV during the Early Archean, while the absorption spectrum of chlorophyll a is used to quantify the fraction of photosynthetically active radiation absorbed by photosynthetic organisms. UV could have induced photoinhibition at the water surface, thereby strongly affecting the species with low light use efficiency. A higher photosynthetic potential in early marine environments was shown than in the Late Archean as a consequence of the attenuation of UVC and UVB by iron ions, which probably played an important role in the protection of ancient free-floating bacteria from high-intensity UV radiation. Photosynthetic organisms in Archean coastal and ocean environments were probably abundant in the first 5 and 25 m of the water column, respectively. However, species with a relatively high efficiency in the use of light could have inhabited ocean waters up to a depth of 200 m and show a Deep Chlorophyll Maximum near 60 m depth. We show that the electromagnetic radiation from the Sun, both UV and visible light, could have determined the vertical distribution of Archean marine photosynthetic organisms.

Extreme Sea Conditions in Shallow Water: Estimation based on in-situ measurements

NASA Astrophysics Data System (ADS)

Le Crom, Izan; Saulnier, Jean-Baptiste

2013-04-01

The design of marine renewable energy devices and components is based, among others, on the assessment of the environmental extreme conditions (winds, currents, waves, and water level) that must be combined together in order to evaluate the maximal loads on a floating/fixed structure, and on the anchoring system over a determined return period. Measuring devices are generally deployed at sea over relatively short durations (a few months to a few years), typically when describing water free surface elevation, and extrapolation methods based on hindcast data (and therefore on wave simulation models) have to be used. How to combine, in a realistic way, the action of the different loads (winds and waves for instance) and which correlation of return periods should be used are highly topical issues. However, the assessment of the extreme condition itself remains a not-fully-solved, crucial, and sensitive task. Above all in shallow water, extreme wave height, Hmax, is the most significant contribution in the dimensioning process of EMR devices. As a case study, existing methodologies for deep water have been applied to SEMREV, the French marine energy test site. The interest of this study, especially at this location, goes beyond the simple application to SEMREV's WEC and floating wind turbines deployment as it could also be extended to the Banc de Guérande offshore wind farm that are planned close by. More generally to pipes and communication cables as it is a redundant problematic. The paper will first present the existing measurements (wave and wind on site), the prediction chain that has been developed via wave models, the extrapolation methods applied to hindcast data, and will try to formulate recommendations for improving this assessment in shallow water.

Pathways for degradation of plastic polymers floating in the marine environment.

PubMed

Gewert, Berit; Plassmann, Merle M; MacLeod, Matthew

2015-09-01

Each year vast amounts of plastic are produced worldwide. When released to the environment, plastics accumulate, and plastic debris in the world's oceans is of particular environmental concern. More than 60% of all floating debris in the oceans is plastic and amounts are increasing each year. Plastic polymers in the marine environment are exposed to sunlight, oxidants and physical stress, and over time they weather and degrade. The degradation processes and products must be understood to detect and evaluate potential environmental hazards. Some attention has been drawn to additives and persistent organic pollutants that sorb to the plastic surface, but so far the chemicals generated by degradation of the plastic polymers themselves have not been well studied from an environmental perspective. In this paper we review available information about the degradation pathways and chemicals that are formed by degradation of the six plastic types that are most widely used in Europe. We extrapolate that information to likely pathways and possible degradation products under environmental conditions found on the oceans' surface. The potential degradation pathways and products depend on the polymer type. UV-radiation and oxygen are the most important factors that initiate degradation of polymers with a carbon-carbon backbone, leading to chain scission. Smaller polymer fragments formed by chain scission are more susceptible to biodegradation and therefore abiotic degradation is expected to precede biodegradation. When heteroatoms are present in the main chain of a polymer, degradation proceeds by photo-oxidation, hydrolysis, and biodegradation. Degradation of plastic polymers can lead to low molecular weight polymer fragments, like monomers and oligomers, and formation of new end groups, especially carboxylic acids.

Oceanographic gradients and seabird prey community dynamics in glacial fjords

USGS Publications Warehouse

Arimitsu, Mayumi L.; Piatt, John F.; Madison, Erica N.; Conaway, Jeffrey S.; Hillgruber, N.

2012-01-01

Glacial fjord habitats are undergoing rapid change as a result of contemporary global warming, yet little is known about how glaciers influence marine ecosystems. These ecosystems provide important feeding, breeding and rearing grounds for a wide variety of marine organisms, including seabirds of management concern. To characterize ocean conditions and marine food webs near tidewater glaciers, we conducted monthly surveys of oceanographic variables, plankton, fish and seabirds in Kenai Fjords, Alaska, from June to August of 2007 and 2008. We also measured tidal current velocities near glacial features. We found high sediment load from glacial river runoff played a major role in structuring the fjord marine ecosystem. Submerged moraines (sills) isolated cool, fresh, stratified and silt-laden inner fjord habitats from oceanic influence. Near tidewater glaciers, surface layers of turbid glacial runoff limited availability of light to phytoplankton, but macrozooplankton were abundant in surface waters, perhaps due to the absence of a photic cue for diel migration. Fish and zooplankton community structure varied along an increasing temperature gradient throughout the summer. Acoustic measurements indicated that low density patches of fish and zooplankton were available in the surface waters near glacial river outflows. This is the foraging habitat occupied most by Kittlitz's murrelet (Brachyramphus brevirostris), a rare seabird that appears to be specialized for life in glacially influenced environments. Kittlitz's murrelets were associated with floating glacial ice, and they were more likely to occur near glaciers, in deeper water, and in areas with high acoustic backscatter. Kittlitz's murrelet at-sea distribution was limited to areas influenced by turbid glacial outflows, and where prey was concentrated near the surface in waters with low light penetration. Tidewater glaciers impart unique hydrographic characteristics that influence marine plankton and fish communities, and this has cascading effects on marine food webs in these ecosystems.

MULTIMERMAID: A dedicated multichannel seismic/weather/zoological float for monitoring of the oceans

NASA Astrophysics Data System (ADS)

Hello, Y. M.; Bonnieux, S.; Joubert, C.; Sukhovich, A.; Argentino, J.; Yegikyan, M.; Nolet, G.

2013-12-01

Delays of seismic P waves are used to make scans or 3D images of the variations in seismic wave speed in the Earth's interior using the techniques of seismic tomography. Observations of such delays are ubiquitous on the continents but rare in oceanic regions, mostly because of the large cost associated with deploying ocean-bottom seismometers. At the same time, several thousand free-drifting profiling floats measure the temperature, salinity and current of the upper 2000 m of the ocean in the Argo program, but are incapable to record and transmit seismic signals. Simons et al. (JGR, 2009) developed the idea to use such floats in order to compensate for the lack of seismic delay observations, especially in the southern hemisphere. We built and tested a prototype of such a seismological sensor using an Apex float from Teledyne Webb Research, a Rafos hydrophone, and electronics developed in collaboration with Osean, a small engineering firm in France. This `MERMAID', for `Mobile Earthquake Recorder in Marine Areas by Independent Divers', has concluded its final design stage and a fleet of 20 units is available for experiments. Since 2012, half of these floats have been deployed in the Mediterranean and in the South Indian Ocean. 10 more will be deployed early in 2014 near the Galapagos islands in the Pacific. Analysis of the first data is allowing us to sharpen the wavelet-based algorithm parameters used to discriminate P-waves from the continuous input signal and adapt it to specific noise conditions. A new multidisciplinary version of Mermaid using a dedicated hydrophone is designed to enlarge the band pass for acoustic signals with much higher frequency than seismic. By combining the same algorithm using wavelet transforms, and by adopting a different monitoring strategy with a dedicated processing, Mermaid is able to continuously analyzes acoustic signals to detect major seismic events, while at the same time regularly checking for weather phenomena such rain, drizzle, open sea and ice, or whale migration. This extension to multi-purpose applications makes the Mermaid very attractive for the Argo program. In fact, Mermaids using passive low cost sensors form a very light and complementary solution that can easily be integrated with an Argo float since CTD data are taken during ascent. Such multidisciplinary approach should allow seismologists to participate in international programs such as Argo and obtain the dense ocean coverage needed to image the deep structure of the Earth. We estimate that about 300 Mermaids, operated over a time span of five years, can provide a ray coverage beneath the oceans comparable to that now available beneath the continents with the Global Seismic Network (GSN). To compensate for the extra energy needed for multidisciplinary applications, Geoazur and Osean are developing a new float, called Multimermaid, that uses the same 17' glass sphere as the Ocean Bottom Seismometers constructed by Geoazur. The Multimermaid can navigate up to a depth of 3000 m and hold 2.5 times more battery power than a conventional float.

Variability in the Composition of Floating Microplastics by Region and in Time

NASA Astrophysics Data System (ADS)

Donohue, J. L.; Pavlekovsky, K.; Collins, T.; Andrady, A. L.; Proskurowski, G. K.; Lavender Law, K. L.

2016-02-01

Floating microplastics have been documented in all the subtropical oceans and in many regional seas, yet their origin and weathering history are largely unknown. To identify potential indicators of sources of microplastic debris and changes in input over time, we analyzed nearly 3,000 plastic particles collected using a surface-towing plankton net between 1991 and 2014, collected in the North Pacific subtropical gyre, in the Mediterranean Sea, and across the western North Atlantic basin including the subtropical gyre and coastal locations near urban areas. For each particle we analyzed particle form, size (longest dimension and 2-D surface area), mass, color characteristics and polymer type. We hypothesize that regional differences in average or median particle mass and size are a relative indicator of age (time of exposure), where accumulation zones that retain particles for long periods of time have statistically smaller fragments compared to regions closer to presumed sources. Differences in particle form (i.e., fragment, pellet, foam, line/fiber, film) might also reflect proximity to sources as well as form-dependent removal mechanisms such as density increase and sinking (Ryan 2015). Finally, changes in particle composition over time in subtropical gyre reservoirs could provide clues about changes in input as well as mechanisms and time scale of removal. Understanding the inputs, reservoirs, and sinks of open ocean microplastics is a necessary first step to evaluating their risks and impacts to marine life. Ryan, P., 2015. Does size and buoyancy affect the long-distance transport of floating debris? Environ. Res. Lett. 10 084019.

Ocean convergence and the dispersion of flotsam.

PubMed

D'Asaro, Eric A; Shcherbina, Andrey Y; Klymak, Jody M; Molemaker, Jeroen; Novelli, Guillaume; Guigand, Cédric M; Haza, Angelique C; Haus, Brian K; Ryan, Edward H; Jacobs, Gregg A; Huntley, Helga S; Laxague, Nathan J M; Chen, Shuyi; Judt, Falco; McWilliams, James C; Barkan, Roy; Kirwan, A D; Poje, Andrew C; Özgökmen, Tamay M

2018-02-06

Floating oil, plastics, and marine organisms are continually redistributed by ocean surface currents. Prediction of their resulting distribution on the surface is a fundamental, long-standing, and practically important problem. The dominant paradigm is dispersion within the dynamical context of a nondivergent flow: objects initially close together will on average spread apart but the area of surface patches of material does not change. Although this paradigm is likely valid at mesoscales, larger than 100 km in horizontal scale, recent theoretical studies of submesoscales (less than ∼10 km) predict strong surface convergences and downwelling associated with horizontal density fronts and cyclonic vortices. Here we show that such structures can dramatically concentrate floating material. More than half of an array of ∼200 surface drifters covering ∼20 × 20 km 2 converged into a 60 × 60 m region within a week, a factor of more than 10 5 decrease in area, before slowly dispersing. As predicted, the convergence occurred at density fronts and with cyclonic vorticity. A zipperlike structure may play an important role. Cyclonic vorticity and vertical velocity reached 0.001 s -1 and 0.01 ms -1 , respectively, which is much larger than usually inferred. This suggests a paradigm in which nearby objects form submesoscale clusters, and these clusters then spread apart. Together, these effects set both the overall extent and the finescale texture of a patch of floating material. Material concentrated at submesoscale convergences can create unique communities of organisms, amplify impacts of toxic material, and create opportunities to more efficiently recover such material. Copyright © 2018 the Author(s). Published by PNAS.

Ocean convergence and the dispersion of flotsam

PubMed Central

Shcherbina, Andrey Y.; Klymak, Jody M.; Molemaker, Jeroen; Guigand, Cédric M.; Haza, Angelique C.; Haus, Brian K.; Ryan, Edward H.; Jacobs, Gregg A.; Huntley, Helga S.; Chen, Shuyi; McWilliams, James C.; Barkan, Roy; Kirwan, A. D.; Poje, Andrew C.; Özgökmen, Tamay M.

2018-01-01

Floating oil, plastics, and marine organisms are continually redistributed by ocean surface currents. Prediction of their resulting distribution on the surface is a fundamental, long-standing, and practically important problem. The dominant paradigm is dispersion within the dynamical context of a nondivergent flow: objects initially close together will on average spread apart but the area of surface patches of material does not change. Although this paradigm is likely valid at mesoscales, larger than 100 km in horizontal scale, recent theoretical studies of submesoscales (less than ∼10 km) predict strong surface convergences and downwelling associated with horizontal density fronts and cyclonic vortices. Here we show that such structures can dramatically concentrate floating material. More than half of an array of ∼200 surface drifters covering ∼20 × 20 km2 converged into a 60 × 60 m region within a week, a factor of more than 105 decrease in area, before slowly dispersing. As predicted, the convergence occurred at density fronts and with cyclonic vorticity. A zipperlike structure may play an important role. Cyclonic vorticity and vertical velocity reached 0.001 s−1 and 0.01 ms−1, respectively, which is much larger than usually inferred. This suggests a paradigm in which nearby objects form submesoscale clusters, and these clusters then spread apart. Together, these effects set both the overall extent and the finescale texture of a patch of floating material. Material concentrated at submesoscale convergences can create unique communities of organisms, amplify impacts of toxic material, and create opportunities to more efficiently recover such material. PMID:29339497

Development of a statistical oil spill model for risk assessment.

PubMed

Guo, Weijun

2017-11-01

To gain a better understanding of the impacts from potential risk sources, we developed an oil spill model using probabilistic method, which simulates numerous oil spill trajectories under varying environmental conditions. The statistical results were quantified from hypothetical oil spills under multiple scenarios, including area affected probability, mean oil slick thickness, and duration of water surface exposed to floating oil. The three sub-indices together with marine area vulnerability are merged to compute the composite index, characterizing the spatial distribution of risk degree. Integral of the index can be used to identify the overall risk from an emission source. The developed model has been successfully applied in comparison to and selection of an appropriate oil port construction location adjacent to a marine protected area for Phoca largha in China. The results highlight the importance of selection of candidates before project construction, since that risk estimation from two adjacent potential sources may turn out to be significantly different regarding hydrodynamic conditions and eco-environmental sensitivity. Copyright © 2017. Published by Elsevier Ltd.

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

Rashid, A.; Nygaard, C.

The use of concrete in marine environment has gained tremendous popularity in the past decade and is continued to be a very popular material for marine industry in the world today. It has a very diversified use from large offshore platforms and floating structures in the North Sea, Canada and South America to offshore loading terminals and junction platforms in shallow waters in the marshes of southern Louisiana in the Gulf of Mexico. Also, precast concrete sections are extensively used all over the world in the construction of marine structures. Because of their large variety of shapes and sizes, theymore » can be tailored to fit multiple applications in marine environment. The added quality control in the fabrication yard and the ease of installation by lifting makes them a very attractive option. The use of precast concrete sections is gaining a lot of popularity in South America. A lot of fabrication yards are manufacturing these sections locally. There are hundreds of offshore concrete platforms utilizing these sections in Lake Maracaibo, Venezuela. The paper discusses the use of concrete for offshore structures including floaters. It describes some general concepts and advantages to be gained by the use of concrete (precast and cast-in-place) in marine environment. It also discusses some general design considerations required for the use of different types of precast concrete sections that can be utilized for oil and gas platforms and loading terminals. Lastly the paper describes some typical examples of concrete platforms built out of concrete piles, precast concrete girders and beam sections and concrete decking.« less

Microgravity

NASA Image and Video Library

1998-01-01

Dr. Lisa E. Freed of the Massachusetts Institute of Technology and her colleagues have reported that initially disc-like specimens of cartilage tend to become spherical in space, demonstrating that tissues can grow and differentiate into distinct structures in microgravity. The Mir Increment 3 (Sept. 16, 1996 - Jan. 22, 1997) samples were smaller, more spherical, and mechanically weaker than Earth-grown control samples. These results demonstrate the feasibility of microgravity tissue engineering and may have implications for long human space voyages and for treating musculoskeletal disorders on earth. Constructs grown on Mir (A) tended to become more spherical, whereas those grown on Earth (B) maintained their initial disc shape. These findings might be related to differences in cultivation conditions, i.e., videotapes showed that constructs floated freely in microgravity but settled and collided with the rotating vessel wall at 1g (Earth's gravity). In particular, on Mir the constructs were exposed to uniform shear and mass transfer at all surfaces such that the tissue grew equally in all directions, whereas on Earth the settling of discoid constructs tended to align their flat circular areas perpendicular to the direction of motion, increasing shear and mass transfer circumferentially such that the tissue grew preferentially in the radial direction. A and B are full cross sections of constructs from Mir and Earth groups shown at 10-power. C and D are representative areas at the construct surfaces enlarged to 200-power. They are stained red with safranin-O. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). Photo credit: Proceedings of the National Academy of Sciences.

Tissue grown in space in NASA Bioreactor

NASA Technical Reports Server (NTRS)

1998-01-01

Dr. Lisa E. Freed of the Massachusetts Institute of Technology and her colleagues have reported that initially disc-like specimens of cartilage tend to become spherical in space, demonstrating that tissues can grow and differentiate into distinct structures in microgravity. The Mir Increment 3 (Sept. 16, 1996 - Jan. 22, 1997) samples were smaller, more spherical, and mechanically weaker than Earth-grown control samples. These results demonstrate the feasibility of microgravity tissue engineering and may have implications for long human space voyages and for treating musculoskeletal disorders on earth. Constructs grown on Mir (A) tended to become more spherical, whereas those grown on Earth (B) maintained their initial disc shape. These findings might be related to differences in cultivation conditions, i.e., videotapes showed that constructs floated freely in microgravity but settled and collided with the rotating vessel wall at 1g (Earth's gravity). In particular, on Mir the constructs were exposed to uniform shear and mass transfer at all surfaces such that the tissue grew equally in all directions, whereas on Earth the settling of discoid constructs tended to align their flat circular areas perpendicular to the direction of motion, increasing shear and mass transfer circumferentially such that the tissue grew preferentially in the radial direction. A and B are full cross sections of constructs from Mir and Earth groups shown at 10-power. C and D are representative areas at the construct surfaces enlarged to 200-power. They are stained red with safranin-O. NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). Photo credit: Proceedings of the National Academy of Sciences.

Scattering of Tone Bursts from Spherical Shells: Computations Based on Fourier Transform Method.

DTIC Science & Technology

1991-08-30

0 SALP =0. 0 N1=0 SUM=0. 0 CALL STVAL(X,X1,X2 ,ALPN, BETN,CBN1, BN1,SNN1,RH,XSN,X2S,XCS) 20 CONTINUE CE-N2= PCB(N+3)/PCB(N+2) Q=FLOAT (N+1) 88 ANUM-(Q...BETN*BETN1)) FAC=XSIGN* (2. 0*Q-1. 0) SALP = SALP +FAC*ALPN SBET=SBET+FAC* BETN ALPN=ALPN1 BETN=BETN1 SUM=SUM+ADD IF ((ABS(ADD/SUM)).LT.1.OE-8) GO TO 90...J=O N=N±1 XSIGN=-XSIGN GO TO 20 90 J=J+1 IF (J.EQ.5) GO TO 100 N=N+1 XSIGN=-XSIGN GO TO 20 100 YP=(-4.0/(X**2))*SUM FAC=-XSIGN* (2. 0*Q+1.0) SALP = SALP

Light Scattering by Marine Particles: Modeling with Non-spherical Shapes

DTIC Science & Technology

2006-01-01

3896. Gordon, H.R. and Tao Du., 2001, Light scattering by nonspherical particles: application to coccoliths detached from Emiliania huxleyi ... huxleyi using disk-like shapes. Gordon and Du [2001] and Gordon [2004] found that the shape of the backscattering spectrum of detached coccoliths...from E. huxleyi could be well reproduced using a shape consisting of two parallel disks (diameter ~ 2.75 μm and thickness 0.05 μm) separated by 0.3

A 5-fluorouracil-loaded floating gastroretentive hollow microsphere: development, pharmacokinetic in rabbits, and biodistribution in tumor-bearing mice

PubMed Central

Huang, Yu; Wei, Yumeng; Yang, Hongru; Pi, Chao; Liu, Hao; Ye, Yun; Zhao, Ling

2016-01-01

5-Fluorouracil (5-FU) was loaded in hollow microspheres to improve its oral bioavailability. 5-FU hollow microspheres were developed by a solvent diffusion–evaporation method. The effect of Span 80 concentration, ether/ethanol volume ratio, and polyvinyl pyrrolidone/ethyl cellulose weight ratio on physicochemical characteristics, floating, and in vitro release behaviors of 5-FU hollow microspheres was investigated and optimized. The formulation and technology composed of Span 80 (1.5%, w/v), ether/ethanol (1.0:10.0, v/v), and polyvinyl pyrrolidone/ethyl cellulose (1.0:10.0, w/w) were employed to develop three batch samples, which showed an excellent reproducibility. The microspheres were spherical with a hollow structure with high drug loading amount (28.4%±0.5%) and production yield (74.2%±0.6%); they exhibited excellent floating and sustained release characteristics in simulated gastric and intestinal fluid. Pharmacokinetic studies demonstrated that 5-FU hollow microspheres significantly enhanced oral bioavailability (area under curve, [AUC](0−t): 12.53±1.65 mg/L*h vs 7.80±0.83 and 5.82±0.83 mg/L*h) with longer elimination half-life (t1/2) (15.43±2.12 hours vs 2.25±0.22 and 1.43±0.18 hours) and mean residence time (7.65±0.97 hours vs 3.61±0.41 and 2.34±0.35 hours), in comparison with its solid microspheres and powder. In vivo distribution results from tumor-bearing nude mice demonstrated that the animals administered with 5-FU hollow microspheres had much higher drug content in tumor, plasma, and stomach at 1 and 8 hours except for 0.5 hours sample collection time point in comparison with those administered with 5-FU solid microspheres and its powder. These results suggested that the hollow microspheres would be a promising controlled drug delivery system for an oral chemotherapy agent like 5-FU. PMID:27042001

A 5-fluorouracil-loaded floating gastroretentive hollow microsphere: development, pharmacokinetic in rabbits, and biodistribution in tumor-bearing mice.

PubMed

Huang, Yu; Wei, Yumeng; Yang, Hongru; Pi, Chao; Liu, Hao; Ye, Yun; Zhao, Ling

2016-01-01

5-Fluorouracil (5-FU) was loaded in hollow microspheres to improve its oral bioavailability. 5-FU hollow microspheres were developed by a solvent diffusion-evaporation method. The effect of Span 80 concentration, ether/ethanol volume ratio, and polyvinyl pyrrolidone/ethyl cellulose weight ratio on physicochemical characteristics, floating, and in vitro release behaviors of 5-FU hollow microspheres was investigated and optimized. The formulation and technology composed of Span 80 (1.5%, w/v), ether/ethanol (1.0:10.0, v/v), and polyvinyl pyrrolidone/ethyl cellulose (1.0:10.0, w/w) were employed to develop three batch samples, which showed an excellent reproducibility. The microspheres were spherical with a hollow structure with high drug loading amount (28.4%±0.5%) and production yield (74.2%±0.6%); they exhibited excellent floating and sustained release characteristics in simulated gastric and intestinal fluid. Pharmacokinetic studies demonstrated that 5-FU hollow microspheres significantly enhanced oral bioavailability (area under curve, [AUC](0-t): 12.53±1.65 mg/L(*)h vs 7.80±0.83 and 5.82±0.83 mg/L(*)h) with longer elimination half-life (t1/2) (15.43±2.12 hours vs 2.25±0.22 and 1.43±0.18 hours) and mean residence time (7.65±0.97 hours vs 3.61±0.41 and 2.34±0.35 hours), in comparison with its solid microspheres and powder. In vivo distribution results from tumor-bearing nude mice demonstrated that the animals administered with 5-FU hollow microspheres had much higher drug content in tumor, plasma, and stomach at 1 and 8 hours except for 0.5 hours sample collection time point in comparison with those administered with 5-FU solid microspheres and its powder. These results suggested that the hollow microspheres would be a promising controlled drug delivery system for an oral chemotherapy agent like 5-FU.

78 FR 27913 - Revision of Crane Regulation Standards for Mobile Offshore Drilling Units (MODUs), Offshore...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-13

...The Coast Guard proposes to revise regulations related to the design, certification, inspection, and testing of cranes. These regulations apply to cranes installed on Mobile Offshore Drilling Units (MODUs), Offshore Supply Vessels (OSVs), and floating Outer Continental Shelf (OCS) facilities. This revision would update industry standards incorporated by reference with more recent versions, which are used by industry and incorporated in Bureau of Safety and Environmental Enforcement regulations. Additionally, the Coast Guard proposes to revise regulations regarding certification, inspection, and testing of cranes by allowing use of additional organizations to act in lieu of Coast Guard marine inspectors.

Multichannel seismic/weather/Zoological monitoring of the oceans

NASA Astrophysics Data System (ADS)

Hello, Yann; Bonnieux, Sebastien; Sukovitch, Alexey; Argentino, Jean-Francois; Nolet, Guust

2013-04-01

Delays of seismic P waves are used to make scans or 3D images of the variations in seismic wave speed in the Earth's interior using the techniques of seismic tomography. Observations of such delays are ubiquitous on the continents but rare in oceanic regions. Free-drifting profiling floats that measure the temperature, salinity and current of the upper 2000 m of the ocean are used by physical oceanographers for continuous monitoring in the Argo program. Recently, seismologists developed the idea to use such floats in order to compensate for the lack of seismic delay observations, especially in the southern hemisphere. In project Globalseis, financed by a grant from the European Research Council (ERC), we have built and tested a prototype of such a seismological sensor using an Apex float from Teledyne Webb Research, a Rafos hydrophone, and electronics developed in collaboration with Osean, a small engineering firm in France. `MERMAID', for `Mobile Earthquake Recorder in Marine Areas by Independent Divers' has concuded its final design stage and a fleet of 20 units is available off the shelf. Two of these floats have been deployed in the Mediterranean sea between Nice and the island of Corsica late 2012, others will be deployed in 2013, in the South Indian Ocean and near Galapagos in the Pacific. Analysis of the first data will allow us to sharpen the wavelet-based algorithm parameters used to discriminate P-waves from the continuous input signal. Ten significant events can be stored in internal memory during an average "parking depth" drift of 10 days at a chosen depth of up to 2 km. Events are classified by interest and when the memory is full, larger events replace minor events. At the end of the preprogrammed mission the float surface and transmit data (health logs and events) in Rudics mode by Iridium satellite network. A major event will force the float to ascent at surface and transmit in a short delay the corresponding recorded data as well as its GPS position. A second, dual channel, prototype version of Mermaid using two dedicated hydrophones is designed to enlarge the band pass for acoustic signals with much higher frequency than seismic. Based on the same algorithm using wavelet transforms, Mermaid continuously analyzes acoustic signals to detect both major seismic events and weather phenomena such rain, drizzle, open sea and ice, or whale migration, during its drift phase. This extension to multi-purpose applications makes the Mermaid very attractive for the Argo program. In fact, Mermaids using passive low cost sensors form a very light and complementary solution that can be integrated with an Argo float; Mermaids listen during the passive drift while CTD data are taken during ascent and descent. Such multidisciplinary approach should allow seismologists to participate in international program such as Argo and obtain the dense ocean coverage needed to image the deep structure of the Earth.

Petermann Glacier, North Greenland: massive calving in 2010 and the past half century

NASA Astrophysics Data System (ADS)

Johannessen, O. M.; Babiker, M.; Miles, M. W.

2011-01-01

Greenland's marine-terminating glaciers drain large amounts of solid ice through calving of icebergs, as well as melting of floating glacial ice. Petermann Glacier, North Greenland, has the Northern Hemisphere's long floating ice shelf. A massive (~270 km2) calving event was observed from satellite sensors in August 2010. In order to understand this in perspective, here we perform a comprehensive retrospective data analysis of Petermann Glacier calving-front variability spanning half a century. Here we establish that there have been at least four massive (100+ km2) calving events over the past 50 years: (1) 1959-1961 (~153 km2), (2) 1991 (~168 km2), (3) 2001 (~71 km2) and (4) 2010 (~270 km2), as well as ~31 km2 calved in 2008. The terminus position in 2010 has retreated ~15 km beyond the envelope of previous observations. Whether the massive calving in 2010 represents natural episodic variability or a response to global and/or ocean warming in the fjord remains speculative, although this event supports the contention that the ice shelf recently has become vulnerable due to extensive fracturing and channelized basal melting.

The next generation Antarctic digital magnetic anomaly map

USGS Publications Warehouse

von Frese, R.R.B; Golynsky, A.V.; Kim, H.R.; Gaya-Piqué, L.; Thébault, E.; Chiappinii, M.; Ghidella, M.; Grunow, A.; ,

2007-01-01

S (Golynsky et al., 2001). This map synthesized over 7.1 million line-kms of survey data available up through 1999 from marine, airborne and Magsat satellite observations. Since the production of the initial map, a large number of new marine and airborne surveys and improved magnetic observations from the Ørsted and CHAMP satellite missions have become available. In addition, an improved core field model for the Antarctic has been developed to better isolate crustal anomalies in these data. The next generation compilation also will likely represent the magnetic survey observations of the region in terms of a high-resolution spherical cap harmonic model. In this paper, we review the progress and problems of developing an improved magnetic anomaly map to facilitate studies of the Antarctic crustal magnetic field

Martian tidal pressure and wind fields obtained from the Mariner 9 infrared spectroscopy experiment

NASA Technical Reports Server (NTRS)

Pirraglia, J. A.; Conrath, B. J.

1973-01-01

Using temperature fields derived from the Mariner 9 infrared spectroscopy experiment, the Martian atmospheric tidal pressure and wind fields are calculated. Temperature as a function of local time, latitude, and atmospheric pressure level is obtained by secular and longitudinal averaging of the data. The resulting temperature field is approximated by a spherical harmonic expansion, retaining one symmetric and one asymmetric term for wavenumber zero and wavenumber one. Vertical averaging of the linearized momentum and continuity equations results in an inhomogeneous tidal equation for surface pressure fluctuations with the driving function related to the temperature field through the geopotential function and the hydrostatic equation. Solutions of the tidal equation show a diurnal fractional pressure amplitude approximately equal to one half of the vertically averaged diurnal fractional temperature amplitude.

Martian tidal pressure and wind fields obtained from the Mariner 9 infrared spectroscopy experiment

NASA Technical Reports Server (NTRS)

Pirraglia, J. A.; Conrath, B. J.

1974-01-01

Using temperature fields derived from the Mariner 9 infrared spectroscopy experiment, the Martian atmospheric tidal pressure and wind fields are calculated. Temperature as a function of local time, latitude, and atmospheric pressure level is obtained by secular and longitudinal averaging of the data. The resulting temperature field is approximated by a spherical harmonic expansion, retaining one symmetric and one asymmetric term each for wavenumber zero and wavenumber one. Vertical averaging of the linearized momentum and continuity equations results in an inhomogeneous tidal equation for surface pressure fluctuations with the driving function related to the temperature field through the geopotential function and the hydrostatic equation. Solutions of the tidal equation show a diurnal fractional pressure amplitude approximately equal to one-half the vertically averaged diurnal fractional temperature amplitude.

Light Scattering by Marine Particles: Modeling with Non-Spherical Shapes

DTIC Science & Technology

2007-09-30

huxleyi using disk-like shapes. Gordon and Du [2001] and Gordon [2004] found that the shape of the backscattering spectrum of detached coccoliths...from E. huxleyi could be well reproduced using a shape consisting of two parallel disks (diameter ~ 2.75 μm and thickness 0.05 μm) separated by 0.3...3886−3896. Gordon, H.R. and Tao Du., 2001, Light scattering by nonspherical particles: application to coccoliths detached from Emiliania

Particle shape impacts export and fate in the ocean through interactions with the globally abundant appendicularian Oikopleura dioica.

PubMed

Conley, Keats R; Sutherland, Kelly R

2017-01-01

Marine microbes exhibit highly varied, often non-spherical shapes that have functional significance for essential processes, including nutrient acquisition and sinking rates. There is a surprising absence of data, however, on how cell shape affects grazing, which is crucial for predicting the fate of oceanic carbon. We used synthetic spherical and prolate spheroid microbeads to isolate the effect of particle length-to-width ratios on grazing and fate in the ocean. Here we show that the shape of microbe-sized particles affects predation by the appendicularian Oikopleura dioica, a globally abundant marine grazer. Using incubation experiments, we demonstrate that shape affects how particles are retained in the house and that the minimum particle diameter is the key variable determining how particles are ingested. High-speed videography revealed the mechanism behind these results: microbe-sized spheroids oriented with the long axis parallel to fluid streamlines, matching the speed and tortuosity of spheres of equivalent width. Our results suggest that the minimum particle diameter determines how elongated prey interact with the feeding-filters of appendicularians, which may help to explain the prevalence of ellipsoidal cells in the ocean, since a cell's increased surface-to-volume ratio does not always increase predation. We provide the first evidence that grazing by appendicularians can cause non-uniform export of different shaped particles, thereby influencing particle fate.

Full-Stokes modeling of grounding line dynamics: some first interplay with measurements

NASA Astrophysics Data System (ADS)

Durand, G.; Gagliardini, O.; Zwinger, T.; Ritz, C.; Le Meur, E.; Rémy, F.

2009-12-01

Movement of the grounding line (i.e, the line between the grounded and the floating part of a marine ice-sheet) is one of the key processes that governs the mass balance of marine ice-sheets. So far, modeling of grounding line migration was inconsistent, leading to poorly reliable forecast of marine ice-sheet evolution. Important theoretical progress has been made these last years to describe the dynamics of the grounding line, and a recently developed full-Stokes model gives consistent results in comparison to this theory. Despite these important breakthroughs, theory as well as the model are restricted to two-dimensional flow line and therefore unable to be applied to a particular three-dimensional glaciological problem. Nevertheless, some first insights can be already drawn from 2D modeling results to improve the adequacy between future modeling and field measurements. We will particularly emphasize on two different aspects. (i) Modeling results have shown the major importance of high grid resolution in the vicinity of the grounding line, questioning strategies for future measurement campaigns of bedrock elevation of coastal glaciers. (ii) An approximately 10 m depression of the surface at the vertical position above the grounding line is a very stable feature produced by the model. Careful investigation of the surface curvature should help to locate grounding line position.

World Gravity Map: a set of global complete spherical Bouguer and isostatic anomaly maps and grids

NASA Astrophysics Data System (ADS)

Bonvalot, S.; Balmino, G.; Briais, A.; Kuhn, M.; Peyrefitte, A.; Vales, N.; Biancale, R.; Gabalda, G.; Reinquin, F.

2012-04-01

We present here a set of digital maps of the Earth's gravity anomalies (surface free air, Bouguer and isostatic), computed at Bureau Gravimetric International (BGI) as a contribution to the Global Geodetic Observing Systems (GGOS) and to the global geophysical maps published by the Commission for the Geological Map of the World (CGMW) with support of UNESCO and other institutions. The Bouguer anomaly concept is extensively used in geophysical interpretation to investigate the density distributions in the Earth's interior. Complete Bouguer anomalies (including terrain effects) are usually computed at regional scales by integrating the gravity attraction of topography elements over and beyond a given area (under planar or spherical approximations). Here, we developed and applied a worldwide spherical approach aimed to provide a set of homogeneous and high resolution gravity anomaly maps and grids computed at the Earth's surface, taking into account a realistic Earth model and reconciling geophysical and geodetic definitions of gravity anomalies. This first version (1.0) has been computed by spherical harmonics analysis / synthesis of the Earth's topography-bathymetry up to degree 10800. The detailed theory of the spherical harmonics approach is given in Balmino et al., (Journal of Geodesy, 2011). The Bouguer and terrain corrections have thus been computed in spherical geometry at 1'x1' resolution using the ETOPO1 topography/bathymetry, ice surface and bedrock models from the NOAA (National Oceanic and Atmospheric Administration) and taking into account precise characteristics (boundaries and densities) of major lakes, inner seas, polar caps and of land areas below sea level. Isostatic corrections have been computed according to the Airy-Heiskanen model in spherical geometry for a constant depth of compensation of 30km. The gravity information given here is provided by the Earth Geopotential Model (EGM2008), developed at degree 2160 by the National Geospatial Intelligence Agency (NGA) (Pavlis et al., 2008) and the DTU10 (Andersen, 2010) who represents the best up-to-date global gravity models (including surface gravity measurements from land, marine and airborne surveys as well as gravity and altimetry satellite measurements). The surface free-air anomaly is computed at the Earth's surface in the context of Molodensky theory and includes corrections from the mass of the atmosphere. The way gravity anomalies are computed on a worldwide basis slightly differs from the classical usage, but meets modern concerns which tend to take into account of the real Earth. The resulting anomaly maps and grids will be distributed for scientific and education purposes by the Commission for the Geological Map of the World (CGMW) (http://ccgm.free.fr) and by the Bureau Gravimetrique International (BGI) (http://bgi.omp.obs-mip.fr). Upgraded versions might be done as soon as new global gravity model will be available (including satellite GOCE data for instance). Institutions who are interested to contribute with new datasets of surface gravity measurements (i.e. ground, marine or airborne gravity data) are also invited to contact BGI bgi@cnes.fr.

Single-camera three-dimensional tracking of natural particulate and zooplankton

NASA Astrophysics Data System (ADS)

Troutman, Valerie A.; Dabiri, John O.

2018-07-01

We develop and characterize an image processing algorithm to adapt single-camera defocusing digital particle image velocimetry (DDPIV) for three-dimensional (3D) particle tracking velocimetry (PTV) of natural particulates, such as those present in the ocean. The conventional DDPIV technique is extended to facilitate tracking of non-uniform, non-spherical particles within a volume depth an order of magnitude larger than current single-camera applications (i.e. 10 cm  ×  10 cm  ×  24 cm depth) by a dynamic template matching method. This 2D cross-correlation method does not rely on precise determination of the centroid of the tracked objects. To accommodate the broad range of particle number densities found in natural marine environments, the performance of the measurement technique at higher particle densities has been improved by utilizing the time-history of tracked objects to inform 3D reconstruction. The developed processing algorithms were analyzed using synthetically generated images of flow induced by Hill’s spherical vortex, and the capabilities of the measurement technique were demonstrated empirically through volumetric reconstructions of the 3D trajectories of particles and highly non-spherical, 5 mm zooplankton.

Vibrio tapetis, the Causative Agent of Brown Ring Disease, Forms Biofilms with Spherical Components.

PubMed

Rodrigues, Sophie; Paillard, Christine; Le Pennec, Gaël; Dufour, Alain; Bazire, Alexis

2015-01-01

Vibrio tapetis is a marine bacterium causing Brown Ring Disease (BRD) in the Manila clam Ruditapes philippinarum. V. tapetis biofilm formation remains unexplored depite the fact that it might be linked to pathogenicity. Our objectives were to characterize the in vitro biofilm formation of V. tapetis and evaluate the effects of culture conditions. Biofilm structure and its matrix composition were examined by confocal laser scanning microscopy and scanning electron microscopy. V. tapetis was able to form biofilms on a glass substratum within 24 h. Polysaccharides and extracellular DNA of the biofilm matrixes were differently distributed depending on the V. tapetis strains. Spherical components of about 1-2 μm diameter were found at the biofilm surface. They contain DNA, proteins, and seemed to be physically linked to bacteria and of cellular nature. Transmission electron microscopy showed that the spherical components were devoid of internal compartments. Temperatures >21°C inhibit BRD whereas low salinity (2%) favor it, none of the both conditions altered V. tapetis' ability to form biofilms in vitro. We suggest therefore that biofilm formation could play a role in the persistence of the pathogen in clam than in BRD symptoms.

Model Scaling of Hydrokinetic Ocean Renewable Energy Systems

NASA Astrophysics Data System (ADS)

von Ellenrieder, Karl; Valentine, William

2013-11-01

Numerical simulations are performed to validate a non-dimensional dynamic scaling procedure that can be applied to subsurface and deeply moored systems, such as hydrokinetic ocean renewable energy devices. The prototype systems are moored in water 400 m deep and include: subsurface spherical buoys moored in a shear current and excited by waves; an ocean current turbine excited by waves; and a deeply submerged spherical buoy in a shear current excited by strong current fluctuations. The corresponding model systems, which are scaled based on relative water depths of 10 m and 40 m, are also studied. For each case examined, the response of the model system closely matches the scaled response of the corresponding full-sized prototype system. The results suggest that laboratory-scale testing of complete ocean current renewable energy systems moored in a current is possible. This work was supported by the U.S. Southeast National Marine Renewable Energy Center (SNMREC).

Realization of hydrodynamic experiments on quasi-2D liquid crystal films in microgravity

NASA Astrophysics Data System (ADS)

Clark, Noel A.; Eremin, Alexey; Glaser, Matthew A.; Hall, Nancy; Harth, Kirsten; Klopp, Christoph; Maclennan, Joseph E.; Park, Cheol S.; Stannarius, Ralf; Tin, Padetha; Thurmes, William N.; Trittel, Torsten

2017-08-01

Freely suspended films of smectic liquid crystals are unique examples of quasi two-dimensional fluids. Mechanically stable and with quantized thickness of the order of only a few molecular layers, smectic films are ideal systems for studying fundamental fluid physics, such as collective molecular ordering, defect and fluctuation phenomena, hydrodynamics, and nonequilibrium behavior in two dimensions (2D), including serving as models of complex biological membranes. Smectic films can be drawn across openings in planar supports resulting in thin, meniscus-bounded membranes, and can also be prepared as bubbles, either supported on an inflation tube or floating freely. The quantized layering renders smectic films uniquely useful in 2D fluid physics. The OASIS team has pursued a variety of ground-based and microgravity applications of thin liquid crystal films to fluid structure and hydrodynamic problems in 2D and quasi-2D systems. Parabolic flights and sounding rocket experiments were carried out in order to explore the shape evolution of free floating smectic bubbles, and to probe Marangoni effects in flat films. The dynamics of emulsions of smectic islands (thicker regions on thin background films) and of microdroplet inclusions in spherical films, as well as thermocapillary effects, were studied over extended periods within the OASIS (Observation and Analysis of Smectic Islands in Space) project on the International Space Station. We summarize the technical details of the OASIS hardware and give preliminary examples of key observations.

A Measurement of the Energy Spectra of Cosmic Rays from 20 to 1000 GeV Per Amu

NASA Technical Reports Server (NTRS)

Gregory, J. C.; Thoburn, C.; Smith, A. E.; Petruzzo, J. J., III; Austin, R. W.; Derrickson, J. H.; Parnell, T. A.; Masheder, M. R. W.; Fowler, P. H.

1997-01-01

The design features and operational performance from the test flight of the fourth generation of spherical geometry cosmic ray detectors developed at Bristol University (Bristol University Gas Scintillator 4 - BUGS-4) are presented. The flight from Ft. Sumner (NM) in Sept. 1993 was the premier flight of a large (1m radius) spherical drift chamber which also gave gas scintillation and Cerenkov signals. The combinations of this chamber with one gas and two solid Cerenkov radiators lead to a large aperture factor (4.5 m2sr), but low (approximately 3.5 g/sq cm) instrument mass over the energy sensitive range 1 to several hundred GeV/a. Moreover, one simple timing measurement determined the impact parameter which provided a trajectory (path length) correction for all detector elements. This innovative and efficient design will be of interest to experimental groups engaged in studies of energetic charged particles. Although there were technical problems on the flight, which were compounded by the total destruction of BUGS-4 by fire while landing in Oklahoma, there was a period of stable operation during which the instrument was exposed at float altitude (approximately 125,000 ft.) to high energy cosmic rays. We present the performance of the instrument as determined from the analysis of these data and an appraisal of its novel design features. Suggestions for design improvements in a future instrument are made.

Don't bet against the natal homing abilities of marine fishes.

PubMed

Bentzen, Paul; Bradbury, Ian R

2016-06-01

Whether marine fishes are capable of homing to their natal areas has long been something of an enigma. For some estuarine species or sharks (which have extended nondispersal juvenile stages or are born as relatively large, fully formed juveniles), the answer is clearly 'yes' (Thorrold et al. ; Feldheim et al. ), but for most marine fishes, the issue is much more mysterious. Many species have free-floating eggs, and most have pelagic, passively dispersing larvae. It is challenging to imagine how adult fish might navigate to a region of the ocean they experienced only as eggs or larvae, and easier to assume that such dispersal leads inexorably to high gene flow, and even panmixia. One way to resolve the conundrum would be to track fish from hatching to reproduction, but for marine fishes with tiny eggs and drifting larvae, this is notoriously difficult to do (Bradbury & Laurel ). In this issue of Molecular Ecology, Bonanomi et al. () use a creative approach to solve this challenge for Atlantic cod (Gadus morhua) populations that mingle in the vicinity of Greenland. They show that cod that disperse more than a 1000 km away from Iceland as eggs and larvae, then spend years growing on the far side of Greenland, while mixing with two local populations, return as adults to spawning areas near Iceland - and further, that this behaviour has remained stable over more than six decades. They manage this feat with a clever use of historical cod tracking data, modern genomic data and genetic analysis of decades-old DNA obtained from archived materials. Their results have important implications for our view of the biocomplexity of marine fish populations, and how we should manage them. © 2016 John Wiley & Sons Ltd.

On the design of a prototype model of the floating wave power device ``Mighty Whale``

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

Hotta, H.; Washio, Y.; Yokozawa, H.

1996-12-31

The Mighty Whale is a floating wave power device to convert the wave energy to other convenient energy for the conservation of the sea, and to create the calm sea area such as a floating breakwater. JAMSTEC (Japan Marine Science and Technology Center) has been promoting the R and D on this Mighty Whale since 1986. Already, the authors have finished fundamental development by theoretical, numerical and experimental study on the basic Mighty Whale. By 1996, they will finish designing the prototype model of the Mighty Whale, will start to construct it, and will carry out the open sea testmore » between 1998 and 1999 at the coastal sea of Japan. The dimensions of the Mighty Whale are 50m in length, 30m in breadth and it has 3 air chambers, 3 units of the air turbines and generators of 50 kW rated power. It will be moored by mooring chains and anchors at the site of about 35m water depth. The mechanism to absorb the wave energy is of the OWC (Oscillating Water Column) type with the Wells Turbine. Its efficiency to absorb the wave energy is about 40--50% on average in regular waves, and it can make in the lee zone the height of incident waves about one half under 8 sec of the significant wave period. Because of such behavior, and from the view point of sustainable development at the coastal zone, the authors recognize the Mighty Whale can be a convenient and beneficial structure for the coastal development. In this paper, they introduce this design, and discuss the utilization of the Mighty Whale for the coastal development.« less

Forward scattering and backscattering of solar radiation by the stratospheric limb after Mount St. Helens eruption

NASA Technical Reports Server (NTRS)

Ackerman, M.; Lippens, C.

1982-01-01

Stratospheric limb radiance profiles versus altitude of closest approach of the line of sight to the Earth's surface have been measured before and after the Mount St. Helens eruptions by means of photographs taken from a Sun-oriented balloon gondola floating above 35 km altitude over France. Preliminary data were reported for flights in October 1979 and in May and June 1980. The radiance integrated along the line of sight as in-situ radiance (R) can be derived taking into account absorption by ozone and air. The onion peeling inversion method was used to derive the vertical radiance (R) profiles respectively. The values of R were determined in the solar azimuth. The solar elevation angles are chosen larger for the backscattering observation than for the forward scattering observation to deal with as similar illumination conditions as possible despite the Earth's sphericity.

Biasing, Acquisition and Interpretation of a Dense Langmuir Probe Array in NSTX

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

Jaworski, M. A.; Kallman, J.; Kaita, R.

2010-09-22

A dense array of 99 Langmuir probes has been installed in the lower divertor region of the National Spherical Torus Experiments (NSTX). This array is instrumented with a system of elec- tronics that allows flexibility in the choice of probes to bias as well as the type of measurement (including standard swept, single probe, triple probe and operation as passive floating potential and scrape-off-layer (SOL) current monitors). The use of flush-mounted probes requires careful inter- pretation. The time dependent nature of the SOL makes swept-probe traces difficult to interpret. To overcome these challenges, the single- and triple-Langmuir probe signals aremore » used in comple- mentary fashion to determine the temperature and density at the probe location. A comparison to mid-plane measurements is made. Work is supported by DOE contracts DE-AC02-09CHI1466 and DE-PS02-07ER07-29.« less

Support mechanism for a mirrored surface or other arrangement

DOEpatents

Cutburth, Ronald W.

1987-01-01

An adjustment mechanism such as a three point spherical mount for adjustably supporting a planer mirror or other type of arrangement relative to a plane defined by a given pair of intersecting perpendicular axes is disclosed herein. This mechanism includes first means for fixedly supporting the mirror or other arrangement such that the latter is positionable within the plane defined by the given pair of intersecting perpendicular axes. This latter means and the mirror or other such arrangement are supported by second means for limited movement back and forth about either of the intersecting axes. Moreover, this second means supports the first means and the mirror or other arrangement such that the latter is not movable in any other way whereby the point on the mirror or other arrangement coinciding with the intersection of the given axes does not move or float, thereby making the ability to adjust the mirror or other such arrangement more precise and accurate.

Exfoliated graphite/titanium dioxide nanocomposites for photodegradation of eosin yellow

NASA Astrophysics Data System (ADS)

Ndlovu, Thabile; Kuvarega, Alex T.; Arotiba, Omotayo A.; Sampath, Srinivasan; Krause, Rui W.; Mamba, Bhekie B.

2014-05-01

An improved photocatalyst consisting of a nanocomposite of exfoliated graphite and titanium dioxide (EG-TiO2) was prepared. SEM and TEM micrographs showed that the spherical TiO2 nanoparticles were evenly distributed on the surface of the EG sheets. A four times photocatalytic enhancement was observed for this floating nanocomposite compared to TiO2 and EG alone for the degradation of eosin yellow. For all the materials, the reactions followed first order kinetics where for EG-TiO2, the rate constant was much higher than for EG and TiO2 under visible light irradiation. The enhanced photocatalytic activity of EG-TiO2 was ascribed to the capability of graphitic layers to accept and transport electrons from the excited TiO2, promoting charge separation. This indicates that carbon, a cheap and abundant material, can be a good candidate as an electron attracting reservoir for photocatalytic organic pollutant degradation.

Research on large-aperture primary mirror supporting way of vehicle-mounted laser communication system

NASA Astrophysics Data System (ADS)

Meng, Lixin; Meng, Lingchen; Zhang, Yiqun; Zhang, Lizhong; Liu, Ming; Li, Xiaoming

2018-01-01

In the satellite to earth laser communication link, large-aperture ground laser communication terminals usually are used in order to realize the requirement of high rate and long distance communication and restrain the power fluctuation by atmospheric scintillation. With the increasing of the laser communication terminal caliber, the primary mirror weight should also be increased, and selfweight, thermal deformation and environment will affect the surface accuracy of the primary mirror surface. A high precision vehicular laser communication telescope unit with an effective aperture of 600mm was considered in this paper. The primary mirror is positioned with center hole, which back is supported by 9 floats and the side is supported by a mercury band. The secondary mirror adopts a spherical adjusting mechanism. Through simulation analysis, the system wave difference is better than λ/20 when the primary mirror is in different dip angle, which meets the requirements of laser communication.

The effects of ferrocene concentration on CNT growth on micron silica gel

NASA Astrophysics Data System (ADS)

Othman, Raja N.; Wilkinson, Arthur N.

2017-12-01

The growth of CNT on micron size spherical silica gel of high porosity was performed in this work. The CNT was grown via floating catalyst chemical vapor deposition method (FCCVD). The reaction temperature and time were kept at 760 °C and 3 hours, respectively. The concentration of the catalyst used, which was ferrocene, was varied from 1 wt. % to 9.6 wt. %, with respect to toluene. Striking difference in the morphology of the synthesized tubes was observed using Field Emission Scanning Electron Microscope (FESEM) and Transmission Electron Microscope (TEM) images. The quality and quantity of the CNT were further characterized via Raman Spectroscopy and Thermogravimetric Analysis. Based on these characterizations, it was found that the ferrocene concentration greatly affects the morphology of the obtained CNT; with 1 wt.% and 9.6 wt.% ferrocene concentrations yield CNT of bigger outer diameters, compared to the CNT obtained from 5 wt.% ferrocene concentrations.

Toward the Autonomous Recording and Transmission of Seismic Data from the Oceans: Testing the Son-O-Mermaid Float in the Sargasso Sea

NASA Astrophysics Data System (ADS)

Simon, J. D.; Simons, F. J.; Vincent, H. T.; Nolet, G.

2015-12-01

We report on the deployment of two new Son-O-Mermaid floats into theSargasso Sea during a cruise aboard the R/V Atlantic Explorer, whichdeparted from Bermuda in May of 2015. Son-O-Mermaid is a freelyfloating and autonomous oceangoing system composed of a surface buoyconnected to a length of cable from which a three-hydrophone array issuspended. The main objective of the Son-O-Mermaid project is torecord signals suitable for global tomography in the deep ocean andprovide the seismic community with an abundance of novel raypaths frompreviously unsampled regions of the Earth. The Son-O-Mermaid float,with its ability to continually record, analyze, and transmit seismicdata from the oceans in near-real time has the potential torevolutionize the field of seismology. We analyze new data returnedfrom this deployment, a previous Son-O-Mermaid test, as well as theongoing MERMAID mission in the time, spectral, and wavelet domains. Afull description of the float and deployment report will be presented.A short-term goal of the project is determining realistic magnitude,distance, and pressure relationships for teleseismic earthquakes thatare recorded in the water column. Our analysis of this question isaided by synthetics created using SPECFEM2D and guided by the data,especially noise records recorded by Son-O-Mermaid and MERMAID fromoceans throughout the world. Synthetics provide an idealized waveformuseful for understanding the often very messy and noisy arrivalscommon in midcolumn acoustic recordings. Notably, synthetics allowthe confirmation or rejection of unlikely phases which are matched toearthquake databases after arrivals are detected by automatic pickingalgorithms. Additionally, marine-acoustic processing techniques willbe improved once the underwater acoustic field is better modeled usingrealistic signal-to-noise ratios and noise spectra returned fromSon-O-Mermaid and MERMAID missions. This analysis, particularly whenimplemented in the wavelet domain, is proving fruitful both forcurrent applications such as automating the picking and recognition ofarriving wave trains, and has broad impacts for terrestrial seismologyand the seismic community as a whole.

Application of MAGSAT to Lithospheric Modeling in South America. Part 2: Synthesis of Geologic and Seismic Data for Development of Integrated Crustal Models

NASA Technical Reports Server (NTRS)

Keller, G. R.; Lidiak, E. G.; Hinze, W. J.; Braile, L. W.; Vonfrese, R. R. B. (Principal Investigator)

1984-01-01

Research activities performed on MAGSAT scalar data over South America, Central America, and the adjacent marine areas are summarized. The geologic utility of magnetic anomalies detected by satellite is demonstrated by focusing on the spherical-Earth interpretation of scalar MAGSAT data in combination with ancillary geological and geophysical data to obtain lithospheric models for these regions related to their contemporary crustal dynamics processes, geologic history, current volcanism seismicity and natural resources.

Description and phylogeny of a new prostomatid, Metacystis similis nov. spec. (Protista, Ciliophora) from the East China Sea.

PubMed

Zhang, Xiumei; Ji, Daode; Zhang, Qianqian; Li, Chenghua

2015-10-27

The living morphology and infraciliature of a new marine prostomatid, Metacystis similis nov. spec., have been observed and investigated. Based on both morphological and molecular biological data, several closely-related and easily confused taxa were compared. The diagnosis for this new taxon: cylindrical marine Metacystis with a slightly blunt anterior end, in vivo 50-70 x 18-23 μm; body not loricate, uniformly cinctured by 16-18 transverse rings of cilia, which are also arranged in 32-36 longitudinal kineties; oral apparatus consisting of one circumoral dikinety and six girdles of densely packed monokinetids; single spherical macronucleus located in the center of the body; caudal region possessing one transparent, protruding hemicycle terminal vacuole. Information concerning the small-subunit rRNA gene sequence of the new species was also provided.

A common bottlenose dolphin (Tursiops truncatus) prey handling technique for marine catfish (Ariidae) in the northern Gulf of Mexico

PubMed Central

Barry, Kevin P.; Sinclair, Carrie; Grace, Mark A.; Allen, Jason; Balmer, Brian; Panike, Anna; Toms, Christina; Mullin, Keith D.; Wells, Randall S.

2017-01-01

Few accounts describe predator-prey interactions between common bottlenose dolphins (Tursiops truncatus Montagu 1821) and marine catfish (Ariopsis felis Linnaeus 1766, Bagre marinus Mitchill 1815). Over the course of 50,167 sightings of bottlenose dolphin groups in Mississippi Sound and along the Florida coast of the Gulf of Mexico, severed catfish heads were found floating and exhibiting movements at the surface in close proximity to 13 dolphin groups that demonstrated feeding behavior. These observations prompted a multi-disciplinary approach to study the predator-prey relationship between bottlenose dolphins and marine catfish. A review was conducted of bottlenose dolphin visual survey data and dorsal fin photographs from sightings where severed catfish heads were observed. Recovered severed catfish heads were preserved and studied, whole marine catfish were collected and examined, and stranding network pathology reports were reviewed for references to injuries related to fish spines. Photographic identification analysis confirms eight dolphins associated with severed catfish heads were present in three such sightings across an approximately 350 km expanse of coast between the Mississippi Sound and Saint Joseph Bay, FL. An examination of the severed catfish heads indicated interaction with dolphins, and fresh-caught whole hardhead catfish (A. felis) were examined to estimate the presumed total length of the catfish before decapitation. Thirty-eight instances of significant trauma or death in dolphins attributed to ingesting whole marine catfish were documented in stranding records collected from the southeastern United States of America. Bottlenose dolphins typically adhere to a ram-feeding strategy for prey capture followed by whole prey ingestion; however, marine catfish skull morphology may pose a consumption hazard due to rigid spines that can puncture and migrate through soft tissue, prompting a prey handling technique for certain dolphins, facilitating consumption of the posterior portion of the fish without the head. PMID:28704486

Quantitation of persistent organic pollutants adsorbed on plastic debris from the Northern Pacific Gyre's "eastern garbage patch".

PubMed

Rios, Lorena M; Jones, Patrick R; Moore, Charles; Narayan, Urja V

2010-12-01

Floating marine plastic debris was found to function as solid-phase extraction media, adsorbing and concentrating pollutants out of the water column. Plastic debris was collected in the North Pacific Gyre, extracted, and analyzed for 36 individual PCB congeners, 17 organochlorine pesticides, and 16 EPA priority PAHs. Over 50% contained PCBs, 40% contained pesticides, and nearly 80% contained PAHs. The PAHs included 2, 3 and 4 ring congeners. The PCBs were primarily CB-11, 28, 44, 52, 66, and 101. The pesticides detected were primarily p,p-DDTs and its metabolite, o,p-DDD, as well as BHC (a,b,g and d). The concentrations of pollutants found ranged from a few ppb to thousands of ppb. The types of PCBs and PAHs found were similar to those found in marine sediments. However, these plastic particles were mostly polyethylene which is resistant to degradation and although functioning similarly to sediments in accumulating pollutants, these had remained on or near the ocean surface. Particles collected included intact plastic items as well as many pieces less than 5 mm in size.

14 CFR 27.753 - Main float design.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float design. 27.753 Section 27.753... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 27.753 Main float design. (a) Bag floats. Each bag float must be designed to withstand— (1) The maximum pressure differential...

14 CFR 29.753 - Main float design.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float design. 29.753 Section 29.753... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 29.753 Main float design. (a) Bag floats. Each bag float must be designed to withstand— (1) The maximum pressure differential...

Patterns in connectivity and retention of simulated Tanner crab (Chionoecetes bairdi) larvae in the eastern Bering Sea

NASA Astrophysics Data System (ADS)

Richar, Jonathan I.; Kruse, Gordon H.; Curchitser, Enrique; Hermann, Albert J.

2015-11-01

The eastern Bering Sea (EBS) population of Tanner crab (Chionoecetes bairdi) has exhibited high variability in recruitment to the commercially exploited stock since the late 1970s. Concurrently, apparent shifts in crab distribution have also been observed. Larval advection patterns and associated local retention offer a potential mechanism for these observations. The Regional Ocean Modeling System (ROMS) was used to simulate larval Tanner crab advection patterns over 1978-2004 based on larval hatching sites inferred from the distributions of reproductive females sampled during annual National Marine Fisheries Service trawl surveys. Connectivity among EBS subregions was examined by comparing start and end float locations after 60 days of simulated drift. High levels of retention (>50% of floats) were observed in the majority of source subregions, and contributed significantly to the total number of endpoints in each region. Patterns in advection and resultant interregional connectivity were variable, with strongest sustained connectivity occurring along shelf, within individual domains. Increased settlement potential in the outer domain and southern middle domain after 1990 is consistent with an observed geographic shift in fishery productivity. Apparent reliance of Bristol Bay on local larval retention validates recent spatial fishery management to conserve this area as a subpopulation.

Impact of Basal Hydrology Near Grounding Lines: Results from the MISMIP-3D and MISMIP+ Experiments Using the Community Ice Sheet Model

NASA Astrophysics Data System (ADS)

Leguy, G.; Lipscomb, W. H.; Asay-Davis, X.

2017-12-01

Ice sheets and ice shelves are linked by the transition zone, the region where the grounded ice lifts off the bedrock and begins to float. Adequate resolution of the transition zone is necessary for numerically accurate ice sheet-ice shelf simulations. In previous work we have shown that by using a simple parameterization of the basal hydrology, a smoother transition in basal water pressure between floating and grounded ice improves the numerical accuracy of a one-dimensional vertically integrated fixed-grid model. We used a set of experiments based on the Marine Ice Sheet Model Intercomparison Project (MISMIP) to show that reliable grounding-line dynamics at resolutions 1 km is achievable. In this presentation we use the Community Ice Sheet Model (CISM) to demonstrate how the representation of basal lubrication impacts three-dimensional models using the MISMIP-3D and MISMIP+ experiments. To this end we will compare three different Stokes approximations: the Shallow Shelf Approximation (SSA), a depth-integrated higher-order approximation, and the Blatter-Pattyn model. The results from our one-dimensional model carry over to the 3-D models; a resolution of 1 km (and in some cases 2 km) remains sufficient to accurately simulate grounding-line dynamics.

Verification of a rapid mooring and foundation design tool

DOE PAGES

Weller, Sam D.; Hardwick, Jon; Gomez, Steven; ...

2018-02-15

Marine renewable energy devices require mooring and foundation systems that suitable in terms of device operation and are also robust and cost effective. In the initial stages of mooring and foundation development a large number of possible configuration permutations exist. Filtering of unsuitable designs is possible using information specific to the deployment site (i.e. bathymetry, environmental conditions) and device (i.e. mooring and/or foundation system role and cable connection requirements). The identification of a final solution requires detailed analysis, which includes load cases based on extreme environmental statistics following certification guidance processes. Static and/or quasi-static modelling of the mooring and/or foundationmore » system serves as an intermediate design filtering stage enabling dynamic time-domain analysis to be focused on a small number of potential configurations. Mooring and foundation design is therefore reliant on logical decision making throughout this stage-gate process. The open-source DTOcean (Optimal Design Tools for Ocean Energy Arrays) Tool includes a mooring and foundation module, which automates the configuration selection process for fixed and floating wave and tidal energy devices. As far as the authors are aware, this is one of the first tools to be developed for the purpose of identifying potential solutions during the initial stages of marine renewable energy design. While the mooring and foundation module does not replace a full design assessment, it provides in addition to suitable configuration solutions, assessments in terms of reliability, economics and environmental impact. This article provides insight into the solution identification approach used by the module and features the verification of both the mooring system calculations and the foundation design using commercial software. Several case studies are investigated: a floating wave energy converter and several anchoring systems. It is demonstrated that the mooring and foundation module is able to provide device and/or site developers with rapid mooring and foundation design solutions to appropriate design criteria.« less

Verification of a rapid mooring and foundation design tool

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

Weller, Sam D.; Hardwick, Jon; Gomez, Steven

Marine renewable energy devices require mooring and foundation systems that suitable in terms of device operation and are also robust and cost effective. In the initial stages of mooring and foundation development a large number of possible configuration permutations exist. Filtering of unsuitable designs is possible using information specific to the deployment site (i.e. bathymetry, environmental conditions) and device (i.e. mooring and/or foundation system role and cable connection requirements). The identification of a final solution requires detailed analysis, which includes load cases based on extreme environmental statistics following certification guidance processes. Static and/or quasi-static modelling of the mooring and/or foundationmore » system serves as an intermediate design filtering stage enabling dynamic time-domain analysis to be focused on a small number of potential configurations. Mooring and foundation design is therefore reliant on logical decision making throughout this stage-gate process. The open-source DTOcean (Optimal Design Tools for Ocean Energy Arrays) Tool includes a mooring and foundation module, which automates the configuration selection process for fixed and floating wave and tidal energy devices. As far as the authors are aware, this is one of the first tools to be developed for the purpose of identifying potential solutions during the initial stages of marine renewable energy design. While the mooring and foundation module does not replace a full design assessment, it provides in addition to suitable configuration solutions, assessments in terms of reliability, economics and environmental impact. This article provides insight into the solution identification approach used by the module and features the verification of both the mooring system calculations and the foundation design using commercial software. Several case studies are investigated: a floating wave energy converter and several anchoring systems. It is demonstrated that the mooring and foundation module is able to provide device and/or site developers with rapid mooring and foundation design solutions to appropriate design criteria.« less

40 CFR 65.45 - External floating roof converted into an internal floating roof.

Code of Federal Regulations, 2010 CFR

2010-07-01

... External floating roof converted into an internal floating roof. The owner or operator who elects to... 40 Protection of Environment 15 2010-07-01 2010-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION...

Polar versus temperate grounding-line sedimentary systems and marine glacier stability during sea level rise by global warming

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

Powell, R.D.; Pyne, A.R.; Hunter, L.E.

1992-01-01

Marine-ending glaciers may retreat with global warming as sea level rises by ocean thermal expansion. If the sea floor rises by sediment accumulation, then glaciers may not feel the effect of sea level rise. A submersible ROV and other techniques have been used to collect data from temperate and polar glaciers to compare sediment production and mass balance of their grounding-line systems. Temperature Alaskan valley glaciers flow at about 0.2--2 km/a and have high volumes of supraglacial, englacial and subglacial debris. However, most sediment contributed to the base of their tidewater cliffs comes from subglacial streams or squeezing out subglacialmore » sediment and pushing it with other marine sediment into a morainal bank. Blue Glacier, a thin, locally fed polar glacier in Antarctica, flows slowly and has minimal glacial debris. The grounding-line system at the tidewater cliff is a morainal bank that forms solely by pushing of marine sediment. An Antarctic polar outlet glacier, Mackay Glacier, terminating as a floating glacier-tongue, has similar volumes of basal debris to Alaskan temperature glaciers and flows at 250 m/a. However, no subglacial streams issued from Mackay's grounding line and all sedimentation was by rockfall and grainfall rainout from seawater undermelt of the tongue. A grounding-line wedge of glacimarine diamicton is deposited over subglacial (lodgement ) till. Although Antarctic grounding-line accumulation rates are three orders of magnitude smaller than Alaskan rates, both are capable of compensating for predicted rises in sea level by thermal heating from global warming.« less

In silico and in vitro methods to optimize the performance of experimental gastroretentive floating mini-tablets.

PubMed

Eberle, Veronika A; Häring, Armella; Schoelkopf, Joachim; Gane, Patrick A C; Huwyler, Jörg; Puchkov, Maxim

2016-01-01

Development of floating drug delivery systems (FDDS) is challenging. To facilitate this task, an evaluation method was proposed, which allows for a combined investigation of drug release and flotation. It was the aim of the study to use functionalized calcium carbonate (FCC)-based lipophilic mini-tablet formulations as a model system to design FDDS with a floating behavior characterized by no floating lag time, prolonged flotation and loss of floating capability after complete drug release. Release of the model drug caffeine from the mini-tablets was assessed in vitro by a custom-built stomach model. A cellular automata-based model was used to simulate tablet dissolution. Based on the in silico data, floating forces were calculated and analyzed as a function of caffeine release. Two floating behaviors were identified for mini-tablets: linear decrease of the floating force and maintaining of the floating capability until complete caffeine release. An optimal mini-tablet formulation with desired drug release time and floating behavior was developed and tested. A classification system for a range of varied floating behavior of FDDS was proposed. The FCC-based mini-tablets had an ideal floating behavior: duration of flotation is defined and floating capability decreases after completion of drug release.

Mermaid floating seismometer : A versatile Oceanographic profiler dedicated to the Earthscope Ocean Program.

NASA Astrophysics Data System (ADS)

Hello, Y.; Nolet, G.; Bonnieux, S.; Yegikyan, M.; Chao, Y.; Chen, J.

2016-12-01

Mermaids have been developed to improve seismic data coverage in the oceanic domain for imaging of the Earth's interior. The first generation of Mermaids was housed in conventional Argo-type floats, while hardware and software was developed to analyze acoustic signals, determine whether an earthquake has been recorded, and whether the Mermaid should to come up to the surface and transmit to the satellite. Since 2012, we have deployed small test networks of Mermaids in the Indian Ocean, and in the Mediterranean sea, and we present at this meeting the result from a main network of 9 Mermaids deployed since mid 2014 in the Galapagos archipelago to image the deep plume structure. Since then, we have moved from typical cylinder container, which equips most of the Argo Floats, to a more suitable spherical design, which allows for a larger power supply and more versatile payload. The life time of the new Mermaids is 6 years if sampling continuously for seismic signals, e.g. for seismic tomography by providing worldwide coverage of P wave arrival times. The passband can be widened to allow for monitoring of whale and dolphin sounds. An interface board allows to connect up to 8 external sensors to serve other goals (bio-Argo, geochemical, meteorological). This year we have started collaboration with Sea-Trec to equip the Mermaids with an optional new green renewable power source to guaranty its 6 years lifetime even with a full payload. The Mermaids monitor continuously during the parking phase when drifting freely at a depth down to 3000m, but also provide Argo profiles during the descent. We are collaborating with Sea-Bird to customize an SBE37 to equip the Mermaid for salinity measurements. The new Mermaid has all the features to answer many scientific goals, and a project to develop a user-friendly, adaptable, software system has begun in collaboration with i3s. The first stage of a global network, EarthScope-Oceans, will be launched in 2017, and is planned to grow to 500 units to image the deep interior of the Earth.

Analysis of surgical smoke produced by various energy-based instruments and effect on laparoscopic visibility.

PubMed

Weld, Kyle J; Dryer, Stephen; Ames, Caroline D; Cho, Kuk; Hogan, Chris; Lee, Myonghwa; Biswas, Pratim; Landman, Jaime

2007-03-01

We analyzed the smoke plume produced by various energy-based laparoscopic instruments and determined its effect on laparoscopic visibility. The Bipolar Macroforceps, Harmonic Scalpel, Floating Ball, and Monopolar Shears were applied in vitro to porcine psoas muscle. An Aerodynamic Particle Sizer and Electrostatic Classifier provided a size distribution of the plume for particles >500 nm and <500 nm, and a geometric mean particle size was calculated. A Condensation Particle Counter provided the total particle-number concentration. Electron microscopy was used to characterize particle size and shape further. Visibility was calculated using the measured-size distribution data and the Rayleigh and Mie light-scattering theories. The real-time instruments were successful in measuring aerosolized particle size distributions in two size ranges. Electron microscopy revealed smaller, homogeneous, spherical particles and larger, irregular particles consistent with cellular components. The aerosol produced by the Bipolar Macroforceps obscured visibility the least (relative visibility 0.887) among the instruments tested. Particles from the Harmonic Scalpel resulted in a relative visibility of 0.801. Monopolar-based instruments produced plumes responsible for the poorest relative visibility (Floating Ball 0.252; Monopolar Shears 0.026). Surgical smoke is composed of two distinct particle populations caused by the nucleation of vapors as they cool (the small particles) and the entrainment of tissue secondary to mechanical aspects (the large particles). High concentrations of small particles are most responsible for the deterioration in laparoscopic vision. Bipolar and ultrasonic instruments generate a surgical plume that causes the least deterioration of visibility among the instruments tested.

Microwave ablation of ex vivo bovine tissues using a dual slot antenna with a floating metallic sleeve.

PubMed

Ibitoye, Ayo Zaccheaus; Nwoye, Ephraim Okeke; Aweda, Adebayo Moses; Oremosu, Ademola A; Anunobi, Chidozie Charles; Akanmu, Nurudeen Olanrewaju

2016-12-01

To study the efficiency of a dual slot antenna with a floating metallic sleeve on the ablation of different ex vivo bovine tissues. COMSOL Multiphysics® version 4.4 (Stockholm, Sweden), which is based on finite element methods (FEM), was used to design and simulate monopole and dual slot with sleeve antennas. Power, specific absorption rate (SAR), temperature and necrosis distributions in the selected tissues were determined using these antennas. Monopole and dual slot with sleeve antennas were designed, simulated, constructed and applied in this study based on a semi-rigid coaxial cable. Ex vivo experiments were performed on liver, lung, muscle and heart of bovine obtained from a public animal slaughter house. The microwave energy was delivered using a 2.45 GHz solid-state microwave generator at 40 W for 3, 5 and 10 min. Aspect ratio, ablation length and ablation diameter were also determined on ablated tissues and compared with simulated results. Student's t-test was used to compare the statistically significant difference between the performance of the two antennas. The dual slot antenna with sleeve produces localised microwave energy better than the monopole antenna in all ablated tissues using simulation and experimental validation methods. There were significant differences in ablation diameter and aspect ratio between the sleeve antenna and monopole antenna. Additionally, there were no significant differences between the simulation and experimental results. This study demonstrated that the dual slot antenna with sleeve produced larger ablation zones and higher sphericity index in ex vivo bovine tissues with minimal backward heating when compared with the monopole antenna.

Simple display system of mechanical properties of cells and their dispersion.

PubMed

Shimizu, Yuji; Kihara, Takanori; Haghparast, Seyed Mohammad Ali; Yuba, Shunsuke; Miyake, Jun

2012-01-01

The mechanical properties of cells are unique indicators of their states and functions. Though, it is difficult to recognize the degrees of mechanical properties, due to small size of the cell and broad distribution of the mechanical properties. Here, we developed a simple virtual reality system for presenting the mechanical properties of cells and their dispersion using a haptic device and a PC. This system simulates atomic force microscopy (AFM) nanoindentation experiments for floating cells in virtual environments. An operator can virtually position the AFM spherical probe over a round cell with the haptic handle on the PC monitor and feel the force interaction. The Young's modulus of mesenchymal stem cells and HEK293 cells in the floating state was measured by AFM. The distribution of the Young's modulus of these cells was broad, and the distribution complied with a log-normal pattern. To represent the mechanical properties together with the cell variance, we used log-normal distribution-dependent random number determined by the mode and variance values of the Young's modulus of these cells. The represented Young's modulus was determined for each touching event of the probe surface and the cell object, and the haptic device-generating force was calculated using a Hertz model corresponding to the indentation depth and the fixed Young's modulus value. Using this system, we can feel the mechanical properties and their dispersion in each cell type in real time. This system will help us not only recognize the degrees of mechanical properties of diverse cells but also share them with others.

Simple Display System of Mechanical Properties of Cells and Their Dispersion

PubMed Central

Shimizu, Yuji; Kihara, Takanori; Haghparast, Seyed Mohammad Ali; Yuba, Shunsuke; Miyake, Jun

2012-01-01

The mechanical properties of cells are unique indicators of their states and functions. Though, it is difficult to recognize the degrees of mechanical properties, due to small size of the cell and broad distribution of the mechanical properties. Here, we developed a simple virtual reality system for presenting the mechanical properties of cells and their dispersion using a haptic device and a PC. This system simulates atomic force microscopy (AFM) nanoindentation experiments for floating cells in virtual environments. An operator can virtually position the AFM spherical probe over a round cell with the haptic handle on the PC monitor and feel the force interaction. The Young's modulus of mesenchymal stem cells and HEK293 cells in the floating state was measured by AFM. The distribution of the Young's modulus of these cells was broad, and the distribution complied with a log-normal pattern. To represent the mechanical properties together with the cell variance, we used log-normal distribution-dependent random number determined by the mode and variance values of the Young's modulus of these cells. The represented Young's modulus was determined for each touching event of the probe surface and the cell object, and the haptic device-generating force was calculated using a Hertz model corresponding to the indentation depth and the fixed Young's modulus value. Using this system, we can feel the mechanical properties and their dispersion in each cell type in real time. This system will help us not only recognize the degrees of mechanical properties of diverse cells but also share them with others. PMID:22479595

Charging and shielding of a non-spherical dust grain in a plasma

NASA Astrophysics Data System (ADS)

Zhao, L.; Delzanno, G.

2013-12-01

The interaction of objects with a plasma is a classic problem of plasma physics. Originally, it was investigated in the framework of probe theory but more recently its interest has grown in connection with space and complex or dusty plasmas. It is customary to assume that the dust grains are spherical, and theories such as the Orbital Motion Limited (OML) theory are usually applied to calculate the dust charge. However, in nature dust grains have a variety of sizes and shapes. It is therefore natural to ask about the influence of the dust shape on the charging and shielding process. In order to answer this question, we study the charging and shielding of a non-spherical dust grain immersed in a Maxwellian plasma at rest. We consider prolate ellipsoids, varying parametrically the aspect ratio while keeping the surface area constant. The study is conducted with CPIC [1], a newly developed Particle-In-Cell code in curvilinear geometry that conforms to objects of arbitrary shape. For a plasma with temperature ratio equal to unity and for a dust grain with characteristic size of the order of the Debye length, it is shown that the floating potential has a very weak dependence on the geometry, while the charge on the grain increases by a factor of three when the aspect ratio changes from one (a sphere) to hundred (a needle-like ellipsoid). These results are consistent with the higher capacitance of ellipsoidal dust grains, but also indicate that the screening length depends on the geometry. Scaling studies of the dependence of the charging time and screening length on the aspect ratio and plasma conditions are presented, including theoretical considerations to support the numerical results. [1] G.L. Delzanno, et al, ';CPIC: a curvilinear Particle-In-Cell code for plasma-material interaction studies', under review.

Marine biomass program: plant breeding and genetics. Annual report, September 1984-December 1985

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

Neushul, M.; Harger, B.W.W.; Lewis, R.J.

1986-03-01

By building on past efforts and adding to the data base that has been assembled, and through collaborative research with others, progress has been made toward the long-term goal of growing macroalgae in the sea as a future source of substitute natural gas. It is encouraging that the authors program is being emulated in Japan and Sweden, and that there is growing interest in using the unique GRI kelp seedstock collection by workers in Germany, Japan, Alaska, Oregon, California, and elsewhere. This annual report discusses progress made in propagating kelps, and the floating gulf-weed, Sargassum. Work on kelp genetics hasmore » revealed high levels of compatability between species and genera, based on 166 hybridization tests.« less

Three dimensional adaptive mesh refinement on a spherical shell for atmospheric models with lagrangian coordinates

NASA Astrophysics Data System (ADS)

Penner, Joyce E.; Andronova, Natalia; Oehmke, Robert C.; Brown, Jonathan; Stout, Quentin F.; Jablonowski, Christiane; van Leer, Bram; Powell, Kenneth G.; Herzog, Michael

2007-07-01

One of the most important advances needed in global climate models is the development of atmospheric General Circulation Models (GCMs) that can reliably treat convection. Such GCMs require high resolution in local convectively active regions, both in the horizontal and vertical directions. During previous research we have developed an Adaptive Mesh Refinement (AMR) dynamical core that can adapt its grid resolution horizontally. Our approach utilizes a finite volume numerical representation of the partial differential equations with floating Lagrangian vertical coordinates and requires resolving dynamical processes on small spatial scales. For the latter it uses a newly developed general-purpose library, which facilitates 3D block-structured AMR on spherical grids. The library manages neighbor information as the blocks adapt, and handles the parallel communication and load balancing, freeing the user to concentrate on the scientific modeling aspects of their code. In particular, this library defines and manages adaptive blocks on the sphere, provides user interfaces for interpolation routines and supports the communication and load-balancing aspects for parallel applications. We have successfully tested the library in a 2-D (longitude-latitude) implementation. During the past year, we have extended the library to treat adaptive mesh refinement in the vertical direction. Preliminary results are discussed. This research project is characterized by an interdisciplinary approach involving atmospheric science, computer science and mathematical/numerical aspects. The work is done in close collaboration between the Atmospheric Science, Computer Science and Aerospace Engineering Departments at the University of Michigan and NOAA GFDL.

33 CFR 144.01-1 - Life floats.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Life floats. 144.01-1 Section 144... CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-1 Life floats. Each manned platform shall be provided with at least two approved life floats. The life floats shall have sufficient...

46 CFR 160.027-3 - Additional requirements for life floats.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 6 2010-10-01 2010-10-01 false Additional requirements for life floats. 160.027-3..., CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Life Floats for Merchant Vessels § 160.027-3 Additional requirements for life floats. (a) Each life float must have a platform designed...

46 CFR 160.027-3 - Additional requirements for life floats.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 6 2011-10-01 2011-10-01 false Additional requirements for life floats. 160.027-3..., CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Life Floats for Merchant Vessels § 160.027-3 Additional requirements for life floats. (a) Each life float must have a platform designed...

33 CFR 144.01-1 - Life floats.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Life floats. 144.01-1 Section 144... CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-1 Life floats. Each manned platform shall be provided with at least two approved life floats. The life floats shall have sufficient...

14 CFR 29.757 - Hull and auxiliary float strength.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hull and auxiliary float strength. 29.757... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 29.757 Hull and auxiliary float strength. The hull, and auxiliary floats if used, must withstand the...

33 CFR 144.01-1 - Life floats.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Life floats. 144.01-1 Section 144... CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-1 Life floats. Each manned platform shall be provided with at least two approved life floats. The life floats shall have sufficient...

33 CFR 144.01-1 - Life floats.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Life floats. 144.01-1 Section 144... CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-1 Life floats. Each manned platform shall be provided with at least two approved life floats. The life floats shall have sufficient...

33 CFR 144.01-1 - Life floats.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Life floats. 144.01-1 Section 144... CONTINENTAL SHELF ACTIVITIES LIFESAVING APPLIANCES Manned Platforms § 144.01-1 Life floats. Each manned platform shall be provided with at least two approved life floats. The life floats shall have sufficient...

46 CFR 160.027-3 - Additional requirements for life floats.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 6 2014-10-01 2014-10-01 false Additional requirements for life floats. 160.027-3..., CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Life Floats for Merchant Vessels § 160.027-3 Additional requirements for life floats. (a) Each life float must have a platform designed...

46 CFR 160.027-3 - Additional requirements for life floats.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 6 2013-10-01 2013-10-01 false Additional requirements for life floats. 160.027-3..., CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Life Floats for Merchant Vessels § 160.027-3 Additional requirements for life floats. (a) Each life float must have a platform designed...

46 CFR 160.027-3 - Additional requirements for life floats.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 6 2012-10-01 2012-10-01 false Additional requirements for life floats. 160.027-3..., CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Life Floats for Merchant Vessels § 160.027-3 Additional requirements for life floats. (a) Each life float must have a platform designed...

Load assumptions for the landing impact of seaplanes

NASA Technical Reports Server (NTRS)

Taub, Josef

1931-01-01

The formula for the impact of floats must include the enlargement factor itself as well as the type of enlargement. The latter is preferably characterized by the change in surface loading. It is shown that the enlargement of a small seaplane generally results in a changed float (or boat) loading as well as wing loading. The conditions of starting stipulate the retention of the float loading when changing from single-float (boat) to twin-float arrangement. This contingency is followed by an increased impact factor in the twin-float type against the otherwise equivalent single-float type.

Vegetation, substrate and hydrology in floating marshes in the Mississippi river delta plain wetlands, USA

USGS Publications Warehouse

Sasser, C.E.; Gosselink, J.G.; Swenson, E.M.; Swarzenski, C.M.; Leibowitz, N.C.

1996-01-01

In the 1940s extensive floating marshes (locally called 'flotant') were reported and mapped in coastal wetlands of the Mississippi River Delta Plain. These floating marshes included large areas of Panicum hemitomon-dominated freshwater marshes, and Spartina patens/Scirpus olneyi brackish marshes. Today these marshes appear to be quite different in extent and type. We describe five floating habitats and one non-floating, quaking habitat based on differences in buoyancy dynamics (timing and degree of floating), substrate characteristics, and dominant vegetation. All floating marshes have low bulk density, organic substrates. Nearly all are fresh marshes. Panicum hemitomon floating marshes presently occur within the general regions that were reported in the 1940's by O'Neil, but are reduced in extent. Some of the former Panicum hemitomon marshes have been replaced by seasonally or variably floating marshes dominated, or co-dominated by Sagittaria lancifolia or Eleocharis baldwinii. ?? 1996 Kluwer Academic Publishers.

Electrically floating, near vertical incidence, skywave antenna

DOEpatents

Anderson, Allen A.; Kaser, Timothy G.; Tremblay, Paul A.; Mays, Belva L.

2014-07-08

An Electrically Floating, Near Vertical Incidence, Skywave (NVIS) Antenna comprising an antenna element, a floating ground element, and a grounding element. At least part of said floating ground element is positioned between said antenna element and said grounding element. The antenna is separated from the floating ground element and the grounding element by one or more electrical insulators. The floating ground element is separated from said antenna and said grounding element by one or more electrical insulators.

New insights on poly(vinyl acetate)-based coated floating tablets: characterisation of hydration and CO2 generation by benchtop MRI and its relation to drug release and floating strength.

PubMed

Strübing, Sandra; Abboud, Tâmara; Contri, Renata Vidor; Metz, Hendrik; Mäder, Karsten

2008-06-01

The purpose of this study was to investigate the mechanism of floating and drug release behaviour of poly(vinyl acetate)-based floating tablets with membrane controlled drug delivery. Propranolol HCl containing tablets with Kollidon SR as an excipient for direct compression and different Kollicoat SR 30 D/Kollicoat IR coats varying from 10 to 20mg polymer/cm2 were investigated regarding drug release in 0.1N HCl. Furthermore, the onset of floating, the floating duration and the floating strength of the device were determined. In addition, benchtop MRI studies of selected samples were performed. Coated tablets with 10mg polymer/cm2 SR/IR, 8.5:1.5 coat exhibited the shortest lag times prior to drug release and floating onset, the fastest increase in and highest maximum values of floating strength. The drug release was delayed efficiently within a time interval of 24 h by showing linear drug release characteristics. Poly(vinyl acetate) proved to be an appropriate excipient to ensure safe and reliable drug release. Floating strength measurements offered the possibility to quantify the floating ability of the developed systems and thus to compare different formulations more efficiently. Benchtop MRI studies allowed a deeper insight into drug release and floating mechanisms noninvasively and continuously.

14 CFR 23.753 - Main float design.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float design. 23.753 Section 23.753... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Floats and Hulls § 23.753 Main float design. Each seaplane main float must meet the requirements of § 23.521. [Doc...

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

Rehder, J.B.

The project focuses on an appropriate technology for small-scale hydro power: floating waterwheels and turbines. For background, relic and existing systems such as early floating mills, traditional Amish waterwheels, and micro-hydro systems are examined. In the design phase of the project, new designs for Floating Hydro Power Systems include: an analysis of floatation materials and systems; a floating undershot waterwheel design; a floating cylinder (fiberglass storage tank) design; a submerged tube design; and a design for a floating platform with submerged propellers. Finally, in the applications phase, stream flow data from East Tennessee streams are used in a discussion ofmore » the potential applications of floating hydro power systems in small streams.« less

Map Projection Induced Variations in Locations of Polygon Geofence Edges

NASA Technical Reports Server (NTRS)

Neeley, Paula; Narkawicz, Anthony

2017-01-01

This Paper under-estimates answers to the following question under various constraints: If a geofencing algorithm uses a map projection to determine whether a position is inside/outside a polygon region, how far outside/inside the polygon can the point be and the algorithm determine that it is inside/outside (the opposite and therefore incorrect answer)? Geofencing systems for unmanned aircraft systems (UAS) often model stay-in and stay-out regions using 2D polygons with minimum and maximum altitudes. The vertices of the polygons are typically input as latitude-longitude pairs, and the edges as paths between adjacent vertices. There are numerous ways to generate these paths, resulting in numerous potential locations for the edges of stay-in and stay-out regions. These paths may be geodesics on a spherical model of the earth or geodesics on the WGS84 reference ellipsoid. In geofencing applications that use map projections, these paths are inverse images of straight lines in the projected plane. This projected plane may be a projection of a spherical earth model onto a tangent plane, called an orthographic projection. Alternatively, it may be a projection where the straight lines in the projected plane correspond to straight lines in the latitudelongitude coordinate system, also called a Plate Carr´ee projection. This paper estimates distances between different edge paths and an oracle path, which is a geodesic on either the spherical earth or the WGS84 ellipsoidal earth. This paper therefore estimates how far apart different edge paths can be rather than comparing their path lengths, which are not considered. Rather, the comparision is between the actual locations of the edges between vertices. For edges drawn using orthographic projections, this maximum distance increases as the distance from the polygon vertices to the projection point increases. For edges drawn using Plate Carr´ee projections, this maximum distance increases as the vertices become further from the equator. Distances between geodesics on a spherical earth and a WGS84 ellipsoidal earth are also analyzed, using the WGS84 ellipsoid as the oracle. Bounds on the 2D distance between a straight line and a great circle path, in an orthographically projected plane rather than on the surface of the earth, have been formally verified in the PVS theorem prover, meaning that they are mathematically correct in the absence of floating point errors.

Displaying Planetary and Geophysical Datasets on NOAAs Science On a Sphere (TM)

NASA Astrophysics Data System (ADS)

Albers, S. C.; MacDonald, A. E.; Himes, D.

2005-12-01

NOAAs Science On a Sphere(TM)(SOS)was developed to educate current and future generations about the changing Earth and its processes. This system presents NOAAs global science through a 3D representation of our planet as if the viewer were looking at the Earth from outer space. In our presentation, we will describe the preparation of various global datasets for display on Science On a Sphere(TM), a 1.7-m diameter spherical projection system developed and patented at the Forecast Systems Laboratory (FSL) in Boulder, Colorado. Four projectors cast rotating images onto a spherical projection screen to create the effect of Earth, planet, or satellite floating in space. A static dataset can be prepared for display using popular image formats such as JPEG, usually sized at 1024x2048 or 2048x4096 pixels. A set of static images in a directory will comprise a movie. Imagery and data for SOS are obtained from a variety of government organizations, sometimes post-processed by various individuals, including the authors. Some datasets are already available in the required cylindrical projection. Readily available planetary maps can often be improved in coverage and/or appearance by reprojecting and combining additional images and mosaics obtained by various spacecraft, such as Voyager, Galileo, and Cassini. A map of Mercury was produced by blending some Mariner 10 photo-mosaics with a USGS shaded-relief map. An improved high-resolution map of Venus was produced by combining several Magellan mosaics, supplied by The Planetary Society, along with other spacecraft data. We now have a full set of Jupiter's Galilean satellite imagery that we can display on Science On a Sphere(TM). Photo-mosaics of several Saturnian satellites were updated by reprojecting and overlaying recently taken Cassini flyby images. Maps of imagery from five Uranian satellites were added, as well as one for Neptune. More image processing was needed to add a high-resolution Voyager mosaic to a pre-existing map of Neptune's moon Triton. A map of the cosmic background radiation was produced that shows the early universe from an external perspective. Full details and credits for these maps may be viewed online at http://laps.fsl.noaa.gov/albers/sos/sos.html. Geophysical imagery recently added to SOS includes a real-time global infrared weather satellite animation of Earth. This is a 15-minute, quality controlled animation spanning the most recent month, which draws on a number of geosynchronous and polar-orbiting weather satellites for data. Other meteorological and oceanographic datasets can be displayed, such as animations depicting the three-dimensional drifting of the ARGO buoy network through the oceans. Oceanic buoy observations were overlaid on the "Blue Marble" Earth imagery displayed on Science On a Sphere(TM). A static image shows locations for five different global buoy networks. We also produced two movies that show the drift of >1000 ARGO buoys over a period of several months. The first movie shows only the horizontal buoy drift, and the second modulates the intensities to represent the timing of each buoy dive cycle. Animations in real time are also being produced for sea surface temperatures (and anomalies). These analyses are obtained from web displays provided by the DOD Fleet Numerical Operations Center. With advanced technologies, the possibilities are limitless for displaying additional global datasets on Science On a Sphere(TM) and other spherical projection screens.

Boundary layer models for calving marine outlet glaciers

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

Schoof, Christian; Davis, Andrew D.; Popa, Tiberiu V.

We consider the flow of marine-terminating outlet glaciers that are laterally confined in a channel of prescribed width. In that case, the drag exerted by the channel side walls on a floating ice shelf can reduce extensional stress at the grounding line. If ice flux through the grounding line increases with both ice thickness and extensional stress, then a longer shelf can reduce ice flux by decreasing extensional stress. Consequently, calving has an effect on flux through the grounding line by regulating the length of the shelf. In the absence of a shelf, it plays a similar role by controllingmore » the above-flotation height of the calving cliff. Using two calving laws, one due to Nick et al. (2010) based on a model for crevasse propagation due to hydrofracture and the other simply asserting that calving occurs where the glacier ice becomes afloat, we pose and analyse a flowline model for a marine-terminating glacier by two methods: direct numerical solution and matched asymptotic expansions. The latter leads to a boundary layer formulation that predicts flux through the grounding line as a function of depth to bedrock, channel width, basal drag coefficient, and a calving parameter. By contrast with unbuttressed marine ice sheets, we find that flux can decrease with increasing depth to bedrock at the grounding line, reversing the usual stability criterion for steady grounding line location. Stable steady states can then have grounding lines located on retrograde slopes. We show how this anomalous behaviour relates to the strength of lateral versus basal drag on the grounded portion of the glacier and to the specifics of the calving law used.« less

Boundary layer models for calving marine outlet glaciers

DOE PAGES

Schoof, Christian; Davis, Andrew D.; Popa, Tiberiu V.

2017-10-05

We consider the flow of marine-terminating outlet glaciers that are laterally confined in a channel of prescribed width. In that case, the drag exerted by the channel side walls on a floating ice shelf can reduce extensional stress at the grounding line. If ice flux through the grounding line increases with both ice thickness and extensional stress, then a longer shelf can reduce ice flux by decreasing extensional stress. Consequently, calving has an effect on flux through the grounding line by regulating the length of the shelf. In the absence of a shelf, it plays a similar role by controllingmore » the above-flotation height of the calving cliff. Using two calving laws, one due to Nick et al. (2010) based on a model for crevasse propagation due to hydrofracture and the other simply asserting that calving occurs where the glacier ice becomes afloat, we pose and analyse a flowline model for a marine-terminating glacier by two methods: direct numerical solution and matched asymptotic expansions. The latter leads to a boundary layer formulation that predicts flux through the grounding line as a function of depth to bedrock, channel width, basal drag coefficient, and a calving parameter. By contrast with unbuttressed marine ice sheets, we find that flux can decrease with increasing depth to bedrock at the grounding line, reversing the usual stability criterion for steady grounding line location. Stable steady states can then have grounding lines located on retrograde slopes. We show how this anomalous behaviour relates to the strength of lateral versus basal drag on the grounded portion of the glacier and to the specifics of the calving law used.« less

Evidence of micro-debris ingestion by Sargassum-associated fishes in the northern Gulf of Mexico

NASA Astrophysics Data System (ADS)

Vick, P.; Hernandez, F., Jr.; Muffelman, S.; Lestrade, O.

2016-02-01

Sargassum natans and S. fluitans collectively form a pelagic macroalgae complex (Sargassum) which is commonly found in surface waters of the Western-Central Atlantic Ocean (including the Gulf of Mexico). Mats and windrows of Sargassum support large and diverse assemblages of marine fishes and invertebrates, including many early life stages which use Sargassum as nursery areas. Sargassum is a near-surface habitat, and therefore is subject to oceanographic processes (e.g., Langmuir cells, frontal zones) that aggregate floating objects, including marine debris. Relatively little is known about the impacts of marine debris (which often gets broken down into "micro-debris") within Sargassum communities, although micro-debris particles may serve as vectors for toxic compounds if consumed by organisms. Here we present preliminary results from a pilot study examining the frequency of micro-debris occurrence in the stomachs of Sargassum-associated fishes. Neuston and plankton purse seine nets were used to collect Sargassum and associated fauna during surveys in the northern Gulf of Mexico (May, June and July 2014). Marine debris was present in all Sargassum collections, and ranged from relatively large items (e.g., soda bottles) to smaller particles (e.g., microplastics, monofilament threads). The associated fish community was dominated by relatively few taxa, including pipefishes, filefishes and the Sargassumfish, which collectively comprised approximately 85% of the total catch. Stomach contents from juvenile fishes contained mostly natural prey items, including copepods, small decapods, hydroids, and fishes. Micro-debris particles were observed in the stomachs of eight fish species, including juvenile Mahi Mahi, Planehead Filefish and Bermuda chub, among others. Overall, our initial observations suggest that there is some ingestion of micro-debris by fishes associated with Sargassum, although the frequency of occurrence is relatively low.

Turbine with radial acting seal

DOEpatents

Eng, Darryl S; Ebert, Todd A

2016-11-22

A floating brush seal in a rim cavity of a turbine in a gas turbine engine, where the floating brush seal includes a seal holder in which the floating brush seal floats, and a expandable seal that fits within two radial extending seal slots that maintains a seal with radial displacement of the floating brush seal and the seal holder.

The Aerodynamic Drag of Five Models of Side Floats N.A.C.A. Models 51-E, 51-F, 51-G, 51-H, 51-J

NASA Technical Reports Server (NTRS)

House, R O

1938-01-01

The drag of five models of side floats was measured in the N.A.C.A. 7- by 10-foot wind tunnel. The most promising method of reducing the drag of floats indicated by these tests is lowering the angle at which the floats are rigged. The addition of a step to a float does not always increase the drag in the flying range, floats with steps sometimes having lower drag than similar floats without steps. Making the bow chine no higher than necessary might result in a reduction in air drag because of the lower angle of pitch of the chines. Since side floats are used formally to obtain lateral stability when the seaplane is operating on the water at slow speeds or at rest, greater consideration can be given to factors affecting aerodynamic drag than is possible for other types of floats and hulls.

Hydrodynamic and Aerodynamic Tests of Models of Floats for Single-float Seaplanes NACA Models 41-D, 41-E, 61-A, 73, and 73-A

NASA Technical Reports Server (NTRS)

Parkinson, J B; HOUSE R O

1938-01-01

Tests were made in the NACA tank and in the NACA 7 by 10 foot wind tunnel on two models of transverse step floats and three models of pointed step floats considered to be suitable for use with single float seaplanes. The object of the program was the reduction of water resistance and spray of single float seaplanes without reducing the angle of dead rise believed to be necessary for the satisfactory absorption of the shock loads. The results indicated that all the models have less resistance and spray than the model of the Mark V float and that the pointed step floats are somewhat superior to the transverse step floats in these respects. Models 41-D, 61-A, and 73 were tested by the general method over a wide range of loads and speeds. The results are presented in the form of curves and charts for use in design calculations.

The 2008 North Atlantic Spring Bloom Experiment II: Autonomous Platforms and Mixed Layer Evolution

NASA Astrophysics Data System (ADS)

Lee, C. M.; D'Asaro, E. A.; Perry, M.; Fennel, K.; Gray, A.; Rehm, E.; Briggs, N.; Sackmann, B. S.; Gudmundsson, K.

2008-12-01

The 2008 North Atlantic Spring Bloom Experiment (NAB08) employed a system of drifting floats, mobile gliders and ship-based measurements to resolve patch-scale physical and biological variability over the 3- month course of an entire bloom. Although both autonomous and ship-based elements were essential to achieving NAB08 goals, the autonomous system provided a novel perspective by employing long-range gliders to repeatedly survey the volume surrounding a drifting Lagrangian float, thus characterizing patch- scale bloom evolution. Integration of physical and biogeochemical sensors (temperature, conductivity, dissolved oxygen, chlorophyll and CDOM fluorescence, light transmission, optical backscatter, spectral light, and nitrate) and development of in situ calibration techniques were required to support this new autonomous approach. Energetic, small-scale eddy activity at the experiment site (southeast of Iceland, near the Joint Global Ocean Flux Study and Marine Light Mixed Layer sites) produced a swift, heterogeneous velocity field that challenged the gliders" operational abilities and drove refinements to the piloting techniques used to maintain float-following surveys. Although intentionally deployed outside of energetic eddies, floats and gliders were rapidly entrained into these features. Floats circulated within eddies near the start and end of the experiment, drifting generally northwest, across the basin, in-between. An eddy sampled late in the deployment provided particularly interesting signatures, with elevated biological signals manifest consistently in one quadrant. As measurements were collected in a parcel-following Lagrangian frame, this suggests energetic small-scale exchange process (such as vertical or lateral mixing) paired with fast-acting biological processes capable of modifying the newly entrained water as it navigates its path around the eddy. Despite this energetic kilometer-scale heterogeneity, broadly distributed platforms appeared to experience similar broad, long-timescale trends. Initial mixed layer depths exceeded 200 m, with gradual shoaling punctuated by periods of rapid, storm-driven deepening. In mid-April, a period of calm weather, rapid restratification and exponentially growing chlorophyll fluorescence marks the bloom's start. Although one-dimensional processes (e.g. diapycnal mixing and solar warming) clearly play important roles in producing the spring bloom, the rate and vertical extent of upper ocean restratification indicate that lateral mixing, perhaps wind- or eddy-driven exchange or the slumping of lateral density contrasts, play a more important role in restratifying the upper ocean. These important trigger events present a severe observational challenge as they take place at small (kilometers) spatial scales, are fully three-dimensional and episodic in time. The NAB08 efforts demonstrate how mobile, autonomous platforms can be exploited to resolve these events and their impact over the course of an entire bloom cycle.

Investigation into spore coat properties for the rapid identification of endospores in marine sediments

NASA Astrophysics Data System (ADS)

Rattray, J. E.; Chakraborty, A.; Bernard, B. B.; Brooks, J.; Hubert, C. R.

2017-12-01

Understanding the sediment biogeography of dormant marine thermophilic bacterial endospores (thermospores) has the potential to assist locating and characterising working petroleum systems. The presence of thermospores in cold ocean environments suggests that distribution occurs via hydrocarbon seepage from thermally active reservoirs. Low abundance and endospore coat physiology mean nucleic acid based techniques have limited success for in situ detection of thermospores. Alternative rapid analytical methods are needed so we investigated using the Schaeffer-Fulton (malachite green and safranin) and DAPI (4',6-diamidino-2-phenylindole) staining techniques on thermospores from cultures and marine sediments. Sediment samples from 111 locations in the Eastern Gulf of Mexico (100 to 3300 m water depth; 6 to 600 km apart) were incubated at high temperature, followed by construction of 16S rRNA gene amplicon libraries (V3-V4 region; Illumina MiSeq) revealing enrichment of species-level thermospore OTUs. A sulfate reducing bacterium from site EGM080 was purified and classified based on its rRNA gene sequence as Desulfotomaculum geothermicum. Prior to thermospore staining the culture was kept in the death/ decline phase for 16 weeks to promote sporulation. Samples of D. geothermicum and the source marine sediment were fixed, stained then analysed using brightfield, phase contrast or fluorescence microscopy. Thermospores in pure culture were identified using phase contrast but were difficult to observe in the sediment sample due to particle aggregation. The Schaeffer-Fulton technique aided thermospore identification in a complex sediment sample matrix as thermospores were stained bright green, and also revealed that there were only spores and no (red stained) vegetative cells in the culture. Treatment with DAPI gave dull fluorescing cells but also provided insight into the behaviour of thermospores in sediment suspensions. Spores in the culture medium were free floating but in the sediment suspension they were only attached to aggregated fluorescing material. Further investigation into thermospore association with bioparticles could further our understanding of the passive dispersal of spores in marine environments.

One-dimensional array of gold nanoparticles fabricated using biotemplate and its application to fine FET

NASA Astrophysics Data System (ADS)

Ban, Takahiko; Uenuma, Mutsunori; Migita, Shinji; Okamoto, Naofumi; Ishikawa, Yasuaki; Uraoka, Yukiharu; Yamashita, Ichiro; Yamamoto, Shin-ichi

2018-06-01

By synthesizing AuS nanoparticles (NPs) with spherical shell protein (ferritin) and using a V-groove, a one-dimensional array of NPs was formed at the bottom of the V-groove. It has been reported that AuS NPs are converted to Au NPs by UV/ozone treatment. Floating gate memory (FGM) was fabricated by applying this one-dimensional array to V-grooved junctionless (JL) FETs, V-grooved nin-like-type FETs, and pip-like-type FETs, which are fine FETs. In JL-FETs, it is considered that conversion occurred because of good charge storage efficiency, and operation in the opposite direction to normal FGM operation was seen. In the nin-like and pip-like types devices, the same operation as in conventional FGM was shown, and the width of the memory window was about the same size as when one electron entered one NP. The one-dimensional arrangement of the metal NPs used in this study is considered to be applicable to various fields of nanotechnology.

Temperature-triggered micellization of block copolymers on an ionic liquid surface.

PubMed

Lu, Haiyun; Akgun, Bulent; Wei, Xinyu; Li, Le; Satija, Sushil K; Russell, Thomas P

2011-10-18

In situ neutron reflectivity was used to study thermally induced structural changes of the lamellae-forming polystyrene-block-poly(2-vinylpyridine) (PS-b-P2VP) block copolymer thin films floating on the surface of an ionic liquid (IL). The IL, 1-butyl-3-methylimidazolium trifluoromethanesulfonate, is a nonsolvent for PS and a temperature-tunable solvent for P2VP, and, as such, micellization can be induced at the air-IL interface by changing the temperature. Transmission electron microscopy and scanning force microscopy were used to investigate the resultant morphologies of the micellar films. It was found that highly ordered nanostructures consisting of spherical micelles with a PS core surrounded by a P2VP corona were produced. In addition, bilayer films of PS homopolymer on top of a PS-b-P2VP layer also underwent micellization with increasing temperature but the micellization was strongly dependent on the thickness of the PS and PS-b-P2VP layers. © 2011 American Chemical Society

Assessing the size distribution of droplets in a cloud chamber from light extinction data during a transient regime

NASA Astrophysics Data System (ADS)

Vâjâiac, Sorin Nicolae; Filip, Valeriu; Štefan, Sabina; Boscornea, Andreea

2014-03-01

The paper describes a method of assessing the size distribution of fog droplets in a cloud chamber, based on measuring the time variation of the transmission of a light beam during the gravitational settling of droplets. Using a model of light extinction by floating spherical particles, the size distribution of droplets is retrieved, along with characteristic structural parameters of the fog (total droplet concentration, liquid water content and effective radius). Moreover, the time variation of the effective radius can be readily extracted from the model. The errors of the method are also estimated and fall within acceptable limits. The method proves sensitive enough to resolve various modes in the droplet distribution and to point out changes in the distribution due to diverse types of aerosol present in the chamber or to the thermal condition of the fog. It is speculated that the method can be further simplified to reach an in-situ version for real-time field measurements.

Dynamic behavior and deformation analysis of the fish cage system using mass-spring model

NASA Astrophysics Data System (ADS)

Lee, Chun Woo; Lee, Jihoon; Park, Subong

2015-06-01

Fish cage systems are influenced by various oceanic conditions, and the movements and deformation of the system by the external forces can affect the safety of the system itself, as well as the species of fish being cultivated. Structural durability of the system against environmental factors has been major concern for the marine aquaculture system. In this research, a mathematical model and a simulation method were presented for analyzing the performance of the large-scale fish cage system influenced by current and waves. The cage system consisted of netting, mooring ropes, floats, sinkers and floating collar. All the elements were modeled by use of the mass-spring model. The structures were divided into finite elements and mass points were placed at the mid-point of each element, and mass points were connected by springs without mass. Each mass point was applied to external and internal forces, and total force was calculated in every integration step. The computation method was applied to the dynamic simulation of the actual fish cage systems rigged with synthetic fiber and copper wire simultaneously influenced by current and waves. Here, we also tried to find a relevant ratio between buoyancy and sinking force of the fish cages. The simulation results provide improved understanding of the behavior of the structure and valuable information concerning optimum ratio of the buoyancy to sinking force according to current speeds.

Possibility of AABW source originating from meddle size polynyas along the coast of Australian-Antarctic Basin

NASA Astrophysics Data System (ADS)

Kitade, Y.; Keishi, S.; Yuki, O.; Aoki, S.; Kobayashi, T.; Suga, T.; Ohshima, K. I.

2016-12-01

Antarctic Bottom Water (AABW) is the densest water in the ocean and globally significant; its production at the Antarctic margin is a key component of the global overturning circulation [eg. Marshall and Speer, 2012]. AABW originating from a middle size polynya called Vincennes Bay Polynya (VBP) was discovered recently [Kitade et al., 2014]. The fact that a middle size polynya can be a formation site of AABW suggests the possibility that the unknown formation area further exists along the coast of Australian-Antarctic Basin. A deep profiling float, called "Deep NINJA" which is able to observe temperature and salinity at depths up to 4,000 m, was developed by Japan Agency for Marine-Earth Science and Technology and Tsurumi-Seiki Co. [Kobayashi et al., 2015]. Five deep floats were deployed along 110oE in Jan. 2014. One of them drifted west almost along the continental rise and has been observing 40 profiles within two years. However, no signal of newly formed AABW has been observed except in the region off VBP, which is consistent with the BROKE results [eg. Bindoff et al., 2000) and our analysis result of BROKE data. Although these observations do not completely negate the additional formation of AABW originating from middle size polynyas located west of VBP, their formation volume of AABW is suggested to be much smaller than that from VBP.

Program Converts VAX Floating-Point Data To UNIX

NASA Technical Reports Server (NTRS)

Alves, Marcos; Chapman, Bruce; Chu, Eugene

1996-01-01

VAX Floating Point to Host Floating Point Conversion (VAXFC) software converts non-ASCII files to unformatted floating-point representation of UNIX machine. This is done by reading bytes bit by bit, converting them to floating-point numbers, then writing results to another file. Useful when data files created by VAX computer must be used on other machines. Written in C language.

Use of modular amphibious vehicles for conducting research in coastal zone

NASA Astrophysics Data System (ADS)

Zeziulin, Denis; Makarov, Vladimir; Belyaev, Alexander; Beresnev, Pavel; Kurkin, Andrey

2016-04-01

The project aims to create workable running systems of research complexes, moving along the bottom of coastal areas (in shallow waters) for investigation of waves, currents, sediment transport; investigation of ecosystems and biodiversity assessment of organisms; inspection and monitoring environmental conditions and anthropogenic load on nature; bathymetric studies. With all the variety of functional capabilities of modern robotic systems, possibilities of their application in the context of the study of coastal zones are extremely limited. Conducting research using aerial vehicles is limited to safety conditions of flight. Use of floating robotic systems in environmental monitoring and ecosystem research is only possible in conditions of relatively «soft» wave climate of the coastal zone. For these purposes, there are special amphibians such as remote-controlled vehicle Surf Rover [Daily, William R., Mark A. Johnson, and Daniel A. Oslecki. «Initial Development of an Amphibious ROV for Use in Big Surf.» Marine Technology Society 28.1 (1994): 3-10. Print.], mobile system MARC-1 [«The SPROV'er.» Florida Institute of Technology: Department of Marine and. Environmental Systems. Web. 05 May 2010.]. The paper describes methodological approaches to the selection of the design parameters of a new system.

Grounding line dynamics inferred from a 3D full-Stokes model solving the contact problem

NASA Astrophysics Data System (ADS)

Favier, Lionel; Gagliardini, Olivier; Durand, Gael; Zwinger, Thomas

2010-05-01

The mass balance of marine ice-sheets, such as the West Antarctic Ice Sheet, is mostly controlled by their grounding line dynamics. Most numerical models simulating marine ice-sheets involve simplifications and do not include all the stress gradients. First results obtained with a 3D full-Stokes model for the grounded ice-sheet / floating ice-shelf transition, using the finite-element code Elmer/Ice, are presented. The initial geometry, which takes into account a dome and a calving front, has been laterally extruded from a previously investigated 2D flowline geometry. The grounding line migration is computed by solving the contact problem between the ice and the rigid downward sloping bedrock, where a non linear friction law is applied in the two horizontal directions. The evolutions of the sea-air and sea-ice interfaces are determined by the solution of a local transport equation. The consistency between the 3D model and the analogous results of the flowline model is shown by comparing the results in the basic extruded case, with no normal flux through lateral boundaries. Thereafter, spatially non uniform perturbations are introduced, to simulate the grounding line dynamics under fully three-dimensional perturbations.

New Constraints on Post-LGM WAIS Retreat from the Whales Deep Paleo-ice-stream Trough in Eastern Ross Sea

NASA Astrophysics Data System (ADS)

DeCesare, M.; Bart, P. J.; Rosenheim, B. E.

2016-02-01

New multibeam and seismic data acquired during NBP1502 show that a back-stepping cluster containing at least four grounding zone wedges (GZWs) define a bathymetric saddle on the middle shelf of the Whales Deep paleo-ice-stream trough in eastern Ross Sea. Our synthesis of geophysical data with jumbo piston/kasten cores show that we penetrated diamict, sub-ice shelf and open marine sediments associated with four temporally distinct grounding events. A high number of well-preserved benthic and planktonic foraminifera were found in sediments we interpret to have been deposited in sub-ice shelf and open marine environments. A low number of similarly well-preserved benthic foraminifera were recovered from the underlying ice proximal diamict that was deposited on the GZW foreset. We tentatively propose that the pristine foraminifera are in situ and that these specimens provide a unique opportunity to constrain the retreat of grounded and floating ice from the eastern Ross Sea outer continental shelf. Our ongoing synthesis of new radiocarbon dates, stable isotope (δ18O and δ13C) and element/calcium ratios (e.g., Mg/Ca, B/Ca) will be presented.

Macrofouling communities and the degradation of plastic bags in the sea: an in situ experiment.

PubMed

Pauli, Nora-Charlotte; Petermann, Jana S; Lott, Christian; Weber, Miriam

2017-10-01

The increasing amount of plastic littered into the sea may provide a new substratum for benthic organisms. These marine fouling communities on plastic have not received much scientific attention. We present, to our knowledge, the first comprehensive analysis of their macroscopic community composition, their primary production and the polymer degradation comparing conventional polyethylene (PE) and a biodegradable starch-based plastic blend in coastal benthic and pelagic habitats in the Mediterranean Sea. The biomass of the fouling layer increased significantly over time and all samples became heavy enough to sink to the seafloor. The fouling communities, consisting of 21 families, were distinct between habitats, but not between polymer types. Positive primary production was measured in the pelagic, but not in the benthic habitat, suggesting that large accumulations of floating plastic could pose a source of oxygen for local ecosystems, as well as a carbon sink. Contrary to PE, the biodegradable plastic showed a significant loss of tensile strength and disintegrated over time in both habitats. These results indicate that in the marine environment, biodegradable polymers may disintegrate at higher rates than conventional polymers. This should be considered for the development of new materials, environmental risk assessment and waste management strategies.

Marine debris contamination along undeveloped tropical beaches from northeast Brazil.

PubMed

Santos, Isaac R; Friedrich, Ana Cláudia; Ivar do Sul, Juliana Assunção

2009-01-01

We hypothesize that floating debris leaving polluted coastal bays accumulate on nearby pristine beaches. We examined composition, quantities and distribution of marine debris along approximately 150 km of relatively undeveloped, tropical beaches in Costa do Dendê (Bahia, Brazil). The study site is located south of Salvador City, the largest urban settlement from NE Brazil. Strong spatial variations were observed. Plastics accounted for 76% of the sampled items, followed by styrofoam (14%). Small plastic fragments resultant from the breakdown of larger items are ubiquitous all over the area. Because the dominant littoral drift in Bahia is southward, average beach debris densities (9.1 items/m) along Costa do Dendê were threefold higher than densities previously observed north of Salvador City. River-dominated and stable beaches had higher debris quantities than unstable, erosional beaches. Areas immediately south of the major regional embayments (Camamu and Todos os Santos) were the preferential accumulation sites, indicating that rivers draining populous areas are the major source of debris to the study site. Our results provide baseline information for future assessments. Management actions should focus on input prevention at the hydrographic basin level rather than on cleaning services on beaches.

Tracking the sources and sinks of local marine debris in Hawai'i.

PubMed

Carson, Henry S; Lamson, Megan R; Nakashima, Davis; Toloumu, Derek; Hafner, Jan; Maximenko, Nikolai; McDermid, Karla J

2013-03-01

Plastic pollution has biological, chemical, and physical effects on marine environments and economic effects on coastal communities. These effects are acute on southeastern Hawai'i Island, where volunteers remove 16 metric tons of debris annually from a 15 km coastline. Although the majority is foreign-origin, a portion is locally-generated. We used floating debris-retention booms in two urban waterways to measure the input of debris from Hilo, the island's largest community, and released wooden drifters in nearby coastal waters to track the fate of that debris. In 205 days, 30 kilograms of debris (73.6% plastic) were retained from two watersheds comprising 10.2% of Hilo's developed land area. Of 851 wooden drifters released offshore of Hilo in four events, 23.3% were recovered locally, 1.4% at distant locations, and 6.5% on other islands. Comparisons with modeled surface currents and wind were mixed, indicating the importance of nearshore and tidal dynamics not included in the model. This study demonstrated that local pollutants can be retained nearby, contribute to the island's debris-accumulation area, and quickly contaminate other islands. Copyright © 2012 Elsevier Ltd. All rights reserved.

Reconstructing Holocene seasonal hydrographic variability in the eastern North Atlantic using bivalve shells from St Kilda, Scotland

NASA Astrophysics Data System (ADS)

Alexandroff, Stella; Scourse, James; Butler, Paul; Schöne, Bernd; Reimer, Paula

2017-04-01

Bivalve shells like Arctica islandica and Glycymeris glycymeris can be used as highly resolved archives of past marine climate and long-term biomonitors. The annual growth patterns of the shell reflect the environment the animals live in and by cross-matching these growth patterns it is possible to construct multi-centennial, annually resolved chronologies that form a temporal template for isotope sampling. The aim of this study is to detect a signal of Atlantic hydrographic variability in Scottish Shelf Seas that is as far as possible uncontaminated by other influences. In May 2014, we collected dead valves and young live specimens of G. glycymeris from St Kilda, Outer Hebrides, Scotland, and in April 2016, live specimens of A. islandica were collected at the same location. This area is of particular interest as it is close to the Scottish shelf margin, has negligible freshwater input, and is thought to represent open-ocean North Atlantic signals well. We here present two floating chronologies, each spanning >180 years, built from dead-collected G. glycymeris shells from St Kilda. All the shells in these chronologies were assigned radiocarbon ages between 3700-3300 cal yr BP. By combining the radiocarbon dates and the chronological data derived from cross-matching annual bands in the shells, one of the floating chronologies could be further constrained to 3750-3500 cal yr BP (95% range). Sub-annual δ18O data from the floating chronologies and from the modern specimens show a strong seasonal signal and multi-year trends. We calibrate the δ18O results from the modern specimens with instrumental data, which enables us (subject to the assumption that there has been no change in δ18Owater) to compare mean and seasonal seawater temperatures between the present day and the fourth millennium BP.

Characterization of cement float buoyancy in the stalked barnacle Dosima fascicularis (Crustacea, Cirripedia).

PubMed

Zheden, Vanessa; Kovalev, Alexander; Gorb, Stanislav N; Klepal, Waltraud

2015-02-06

Dosima fascicularis is the only barnacle which can drift autonomously at the water surface with a foam-like cement float. The cement secreted by the animal contains numerous gas-filled cells of different size. When several individuals share one float, their size and not their number is crucial for the production of both volume and mass of the float. The gas content within the cells of the foam gives positive static buoyancy to the whole float. The volume of the float, the gas volume and the positive static buoyancy are positively correlated. The density of the cement float without gas is greater than that of seawater. This study shows that the secreted cement consists of more than 90% water and the gas volume is on average 18.5%. Our experiments demonstrate that the intact foam-like cement float is sealed to the surrounding water.

Characterization of cement float buoyancy in the stalked barnacle Dosima fascicularis (Crustacea, Cirripedia)

PubMed Central

Zheden, Vanessa; Kovalev, Alexander; Gorb, Stanislav N.; Klepal, Waltraud

2015-01-01

Dosima fascicularis is the only barnacle which can drift autonomously at the water surface with a foam-like cement float. The cement secreted by the animal contains numerous gas-filled cells of different size. When several individuals share one float, their size and not their number is crucial for the production of both volume and mass of the float. The gas content within the cells of the foam gives positive static buoyancy to the whole float. The volume of the float, the gas volume and the positive static buoyancy are positively correlated. The density of the cement float without gas is greater than that of seawater. This study shows that the secreted cement consists of more than 90% water and the gas volume is on average 18.5%. Our experiments demonstrate that the intact foam-like cement float is sealed to the surrounding water. PMID:25657839

Biocontrol of fouling pests: Effect of diversity, identity and density of control agents.

PubMed

Atalah, Javier; Newcombe, Emma M; Zaiko, Anastasija

2016-04-01

Augmentative biocontrol, using native natural enemies, has been suggested as a promising tool to control marine biofouling pests on artificial structures. However, there are still important knowledge gaps to be addressed before biocontrol can be considered as a management tool. In a field experiment on floating marine structures we examined intra- and interspecific consumer interactions among biocontrol agents on different surface orientations. We tested the effect of identity, density and diversity of three invertebrates (the 11-arm seastar Coscinasterias muricata, the sea urchin Evechinus chloroticus and the gastropod Cook's turban Cookia sulcata) to reduce established biofouling and to prevent fouling growth on defouled surfaces. High densities of biocontrol agents were not more effective at fouling control (cover and biomass) than low densities. Nor did multi-species treatments function more effectively than mono-specific ones. However, biocontrol agent identity was important, with the 11-arm seastar and Cook's turban being the most effective at fouling reduction and prevention, respectively. Surface orientation had a strong effect on the effectiveness of control agents, with the best results obtained on vertical compared to diagonal and underside surfaces. This study confirmed the potential of biocontrol as a management tool for marine pest, indicating that identity is more important than richness and density of control agents. It also highlighted the limitations of this approach on diagonal and underside surfaces, where control agents have limited retention ability. Copyright © 2016 Elsevier Ltd. All rights reserved.

Plastics and microplastics in the oceans: From emerging pollutants to emerged threat.

PubMed

Avio, Carlo Giacomo; Gorbi, Stefania; Regoli, Francesco

2017-07-01

Plastic production has increased dramatically worldwide over the last 60 years and it is nowadays recognized as a serious threat to the marine environment. Plastic pollution is ubiquitous, but quantitative estimates on the global abundance and weight of floating plastics are still limited, particularly for the Southern Hemisphere and the more remote regions. Some large-scale convergence zones of plastic debris have been identified, but there is the urgency to standardize common methodologies to measure and quantify plastics in seawater and sediments. Investigations on temporal trends, geographical distribution and global cycle of plastics have management implications when defining the origin, possible drifting tracks and ecological consequences of such pollution. An elevated number of marine species is known to be affected by plastic contamination, and a more integrated ecological risk assessment of these materials has become a research priority. Beside entanglement and ingestion of macro debris by large vertebrates, microplastics are accumulated by planktonic and invertebrate organisms, being transferred along food chains. Negative consequences include loss of nutritional value of diet, physical damages, exposure to pathogens and transport of alien species. In addition, plastics contain chemical additives and efficiently adsorb several environmental contaminants, thus representing a potential source of exposure to such compounds after ingestion. Complex ecotoxicological effects are increasingly reported, but the fate and impact of microplastics in the marine environment are still far to be fully clarified. Copyright © 2016 Elsevier Ltd. All rights reserved.

Autonomous Microstructure EM-APEX Floats

DTIC Science & Technology

2016-01-01

Autonomous Microstructure_EM-APEX_Float 4/8/16 at 3:21 PM 1 Title: Autonomous Microstructure EM-APEX Floats Authors: Ren-Chieh Lien1,2...Street Seattle, WA 98105 rcl@uw.edu Abstract: Fast responding FP-07 thermistors have been incorporated on profiling EM-APEX floats to measure...storage board. The raw and processed temperature observations are stored on a microSD card. Results from eight microstructure EM-APEX floats

First measurements with Argo flots in the Southern Baltic Sea

NASA Astrophysics Data System (ADS)

Walczowski, Waldemar; Goszczko, Ilona; Wieczorek, Piotr; Merchel, Malgorzata; Rak, Daniel

2017-04-01

The Argo programme is one of the most important elements of the ocean observing system. Currently almost 4000 Argo floats profile global oceans and deliver real time data. Originally Argo floats were developed for open ocean observations. Therefore a standard float can dive up to 2000 m and deep Argo floats are under development. However in the last years the shallow shelf seas become also interesting for Argo users. Institute of Oceanology Polish Academy of Sciences (IOPAN) participates in the Euro-Argo research infrastructure, the European contribution to Argo system. A legal and governance framework (Euro-Argo ERIC) was set up in May 2014. For a few years IOPAN has deployed floats mostly in the Nordic Seas and the European Arctic region. In the end of 2016 the first Polish Argo float was deployed in the Southern Baltic Sea. Building on the successful experience with Argo floats deployed by the Finnish oceanographers in the Bothnian Sea and Gotland Basin, the IOPAN float was launched in the Bornholm Deep during the fall cruise of IOPAN research vessel Oceania. The standard APEX float equipped with 2-way Iridium communication was used and different modes of operation, required for the specific conditions in the shallow and low saline Baltic Sea, were tested. Settings for the Baltic float are different than for the oceanic mode and were frequently changed during the mission to find the optimum solution. Changing the float parking depth during the mission allows for the limited control of the float drift direction. Results of a high resolution numerical forecast model for the Baltic Sea proved to be a valuable tool for determining the parking depth of the float in the different flow regimes. Trajectory and drift velocity of the Argo float deployed in the Southern Baltic depended strongly on the atmospheric forcing (in particular wind speed and direction), what was clearly manifested during the 'Axel' storm passing over the deployment area in January 2017. The first deployment showed clearly that Argo floats can be a useful tool for the Baltic Sea monitoring as the important element of a more complex, multidisciplinary observing system.

Comparison of Bispectral Index™ values during the flotation restricted environmental stimulation technique and results for stage I sleep: a prospective pilot investigation.

PubMed

Dunham, C Michael; McClain, Jesse V; Burger, Amanda

2017-11-29

To determine whether Bispectral Index™ values obtained during flotation-restricted environment stimulation technique have a similar profile in a single observation compared to literature-derived results found during sleep and other relaxation-induction interventions. Bispectral Index™ values were as follows: awake-state, 96.6; float session-1, 84.3; float session-2, 82.3; relaxation-induction, 82.8; stage I sleep, 86.0; stage II sleep, 66.2; and stages III-IV sleep, 45.1. Awake-state values differed from float session-1 (%difference 12.7%; Cohen's d = 3.6) and float session-2 (%difference 14.8%; Cohen's d = 4.6). Relaxation-induction values were similar to float session-1 (%difference 1.8%; Cohen's d = 0.3) and float session-2 (%difference 0.5%; Cohen's d = 0.1). Stage I sleep values were similar to float session-1 (%difference 1.9%; Cohen's d = 0.4) and float session-2 (%difference 4.3%; Cohen's d = 1.0). Stage II sleep values differed from float session-1 (%difference 21.5%; Cohen's d = 4.3) and float session-2 (%difference 19.6%; Cohen's d = 4.0). Stages III-IV sleep values differed from float session-1 (%difference 46.5%; Cohen's d = 5.6) and float session-2 (%difference 45.2%; Cohen's d = 5.4). Bispectral Index™ values during flotation were comparable to those found in stage I sleep and nadir values described with other relaxation-induction techniques.

Ice sheet-ocean interactions and sea level change

NASA Astrophysics Data System (ADS)

Heimbach, Patrick

2014-03-01

Mass loss from the Greenland and Antarctic ice sheets has increased rapidly since the mid-1990s. Their combined loss now accounts for about one-third of global sea level rise. In Greenland, a growing body of evidence points to the marine margins of these glaciers as the region from which this dynamic response originated. Similarly, ice streams in West Antarctica that feed vast floating ice shelves have exhibited large decadal changes. We review observational evidence and present physical mechanisms that might explain the observed changes, in particular in the context of ice sheet-ocean interactions. Processes involve cover 7 orders of magnitudes of scales, ranging from mm boundary-layer processes to basin-scale coupled atmosphere-ocean variability. We discuss observational needs to fill the gap in our mechanistic understanding.

Floating electrode dielectrophoresis.

PubMed

Golan, Saar; Elata, David; Orenstein, Meir; Dinnar, Uri

2006-12-01

In practice, dielectrophoresis (DEP) devices are based on micropatterned electrodes. When subjected to applied voltages, the electrodes generate nonuniform electric fields that are necessary for the DEP manipulation of particles. In this study, electrically floating electrodes are used in DEP devices. It is demonstrated that effective DEP forces can be achieved by using floating electrodes. Additionally, DEP forces generated by floating electrodes are different from DEP forces generated by excited electrodes. The floating electrodes' capabilities are explained theoretically by calculating the electric field gradients and demonstrated experimentally by using test-devices. The test-devices show that floating electrodes can be used to collect erythrocytes (red blood cells). DEP devices which contain many floating electrodes ought to have fewer connections to external signal sources. Therefore, the use of floating electrodes may considerably facilitate the fabrication and operation of DEP devices. It can also reduce device dimensions. However, the key point is that DEP devices can integrate excited electrodes fabricated by microtechnology processes and floating electrodes fabricated by nanotechnology processes. Such integration is expected to promote the use of DEP devices in the manipulation of nanoparticles.

Changing the paradigm for marine data production, dissemination and validation with Collaborative Platforms. The GlobColour webservice, a prime example which leads to the integration of CWE technologies to build-up virtual research centres.

NASA Astrophysics Data System (ADS)

Fanton d'Andon, Odile; Martin-Lauzer, François-Regis; Mangin, Antoine; Barrot, Gilbert; Clouaire, Stephane; Sardou, Olivier; Demaria, Julien; Serra, Romain

2015-04-01

The GlobColour webservice provides a rich dataset of marine bio-geochemical information for research and education purposes. We report on recent evolutions to improve the functionalities of the service to access EO and in-situ data and check information quality. In addition, a new concept, the Collaborative Platform, support the processing of bespoke information for remote users. At the root of the service is an integrated and automated production chain, processing not only EO satellite data but also in-situ measurements from bio-Argo floats. This production chain provides daily updated bio-geochemical data and performs automated data analysis (merging of sensors, temporal and spatial binning). The GlobColour webservice has been recently upgraded to provide improved navigation and selection capabilities. These evolutions were necessary as the catalogue of EO products has been significantly increased, with many new parameters, new spatial resolution (1 km over Europe in addition to 4 km global products) and projections (rectangular grid in addition to sinus grid). The validation and quality control of the information is essential to demonstrate the fitness-for-purpose of the service. Match-ups between in-situ measurements and EO data are a key element to establish the validity of the information. The standard approach is to perform these match-ups off-line using a database of in-situ measurements, and report the results in a validation document. Two innovations are introduced which greatly increase the value for the user: • An interactive navigation tool allows a detailed analysis the results of the match-ups, with temporal and geographical selection capabilities. Background information for each match-up can be easily retrieved, both for in-situ (measurement identification) and for satellite data (context retrieval, providing information such as cloud coverage and spatial variability). This allows users to get a better insight into the validity of the retrieved data for their particular applications. • Match-ups using real-time EO data and data collected from bio-Argo floats are processed automatically on-the-fly. • This is possible because quality control of the bio-Argo float data is also automated. A dedicated interface has been set-up to monitor the whole fleet of Bio-Argo floats, and access detailed information from each acquired profile. Finally, a Collaborative Platform has been developed to support R&D activities in parallel to the standard production chain, enabling users to work remotely within a dedicated production environment in order to develop new algorithms and methods. The Collaborative Platform is based on a Collaborative Working Environment, a secured IT environment mixing hardware and software elements. It provides access to raw data, to processing and storage facilities, to specific applicative software (e.g. visualisation and post-processing tools). In addition, collaborative tools to exchange data, information and ideas between participants (through forums, web-conferencing…) contribute to create a "Virtual Research Centre" preparing future evolutions of the service. Acknowledgements: This research received funding from the following projects: • MCGS project funded by the Fonds Unique Interministériel, French regional funds PACA and Bretagne, the Fonds Européen de Développement Régional • FP7 Copernicus projects OSS2015 (grant n° 282723) and E-AIMS (grant n° 312642). • The French EQUIPEX project NAOS

A novel control process of cyanobacterial bloom using cyanobacteriolytic bacteria immobilized in floating biodegradable plastic carriers.

PubMed

Nakamura, N; Nakano, K; Sugiura, N; Matsumura, M

2003-12-01

A process using a floating carrier for immobilization of cyanobacteriolytic bacteria, B.cereus N-14, was proposed to realize an effective in situ control of natural floating cyanobacterial blooms. The critical concentrations of the cyanobacteriolytic substance and B.cereus N-14 cells required to exhibit cyanobacteriolytic activity were investigated. The results indicated the necessity of cell growth to produce sufficiently high amounts of the cyanobacteriolytic substance to exhibit its activity and also for conditions enabling good contact between high concentrations of the cyanobacteriolytic substance and cyanobacteria. Floating biodegradable plastics made of starch were applied as a carrier material to maintain close contact between the immobilized cyanobacteriolytic bacteria and floating cyanobacteria. The floating starch-carriers could eliminate 99% of floating cyanobacteria in 4 d. Since B.cereus N-14 could produce the cyanobacteriolytic substance under the presence of starch and some amino acids, the cyanobacteriolytic activity could be attributed to carbon source fed from starch carrier and amino acids eluted from lysed cyanobacteria. Therefore, the effect of using a floating starch-carrier was confirmed from both view points as a carrier for immobilization and a nutrient source to stimulate cyanobacteriolytic activity. The new concept to apply a floating carrier immobilizing useful microorganisms for intensive treatment of a nuisance floating target was demonstrated.

40 CFR 426.50 - Applicability; description of the float glass manufacturing subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... float glass manufacturing subcategory. 426.50 Section 426.50 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GLASS MANUFACTURING POINT SOURCE CATEGORY Float Glass Manufacturing Subcategory § 426.50 Applicability; description of the float glass...

40 CFR 426.50 - Applicability; description of the float glass manufacturing subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... float glass manufacturing subcategory. 426.50 Section 426.50 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GLASS MANUFACTURING POINT SOURCE CATEGORY Float Glass Manufacturing Subcategory § 426.50 Applicability; description of the float glass...

Tethered float liquid level sensor

DOEpatents

Daily, III, William Dean

2016-09-06

An apparatus for sensing the level of a liquid includes a float, a tether attached to the float, a pulley attached to the tether, a rotation sensor connected to the pulley that senses vertical movement of said float and senses the level of the liquid.

40 CFR 264.1085 - Standards: Surface impoundments.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the surface impoundment by installing and operating either of the following: (1) A floating membrane... from a surface impoundment using a floating membrane cover shall meet the requirements specified in... floating membrane cover designed to meet the following specifications: (i) The floating membrane cover...

New method for mass transfer across the surface of non-spherical particles in turbulence

NASA Astrophysics Data System (ADS)

Oehmke, T.; Variano, E. A.

2016-12-01

We present a method for making model particles that allow for the interfacial mass transfer rate to be measured. This is similar to traditional use of gypsum plaster used to measure erosion rates on the timescale of weeks to years. Our new method is useful for measuring erosion rates on the timescale of minutes. We use this to measure the manner in which particle shape affects its rate of dissolution in turbulent flow. The related questions are relevant to mass transfer in turbulence, e.g. in cases of marine biology and pollution by microplastics.

Preliminary results from DIMES: Dispersion in the ACC

NASA Astrophysics Data System (ADS)

Balwada, D.; Speer, K.; LaCasce, J. H.; Owens, B.

2012-04-01

The Diapycnal and Isopynal Mixing Experiment in the Southern Ocean (DIMES) is a CLIVAR process study designed to study mixing in the Antarctic Circumpolar Current. The experiment includes tracer release, float, and small-scale turbulence components. This presentation will report on some results of the float component, from floats deployed across the ACC in the Southeast Pacific Ocean. These are the first subsurface Lagrangian trajectories from the ACC. Floats were deployed to follow approximately a constant density surface for a period of 1-3 years. To help aid the experimental results virtual floats were advected using AVISO data and basic statistics were derived from both deployed and virtual float trajectories. Experimental design, initial results, comparison to virtual floats and single particle and relative dispersion calculations will be presented.

Red Sea Outflow Experiment (REDSOX): DLD2 RAFOS Float Data Report February 2001 - March 2003

DTIC Science & Technology

2005-01-01

1 2. Description of the DLD2 Float and Dual-Release System ................................................................... 2 3. Sound Sources...processing are described in detail. 2. Description of the DLD2 Float and Dual-Release System The DLD2 is a second-generation RAFOS (Ranging And Fixing Of...Sound) float with several improvements over the traditional RAFOS float (see Rossby et al., 1986, for a complete description of the RAFOS system ). A

Biofouling of Cr-Nickel Spray Coated Films on Steel Surfaces

NASA Astrophysics Data System (ADS)

Yoshida, Kento; Kanematsu, Hideyuki; Kuroda, Daisuke; Ikigai, Hajime; Kogo, Takeshi; Yokoyama, Seiji

2012-03-01

Nowadays, corrosion of metals brings us serious economic loss and it often reaches several percentage of GNP. Particularly the marine corrosion was serious and the counter measure was very hard to be established, since the number of factors is huge and complicated. One of the complicated factors in marine corrosion is biofouling. Biofouling was classified into two main categories, microfouling and macrofouling. The former is composed of biofilm formation mainly. Marine bacteria are attached to material surfaces, seeking for nutrition in oligotrophic environment and they excrete polysaccharide to form biofilm on metal surfaces. Then larger living matters are attached on the biofilms to develop biofouling on metal surfaces, which often lead loss and failures of metals in marine environments. From the viewpoint of corrosion protection and maintenance of marine structures, biofouling should be mitigated as much as possible. In this study, we applied spray coating to steels and investigated if chromium-nickel spray coating could mitigate the biofouling, being compared with the conventional aluminium-zinc spray coating in marine environments. The specimens used for this investigation are aluminium, zinc, aluminium-zinc, stacked chromium/nickel and those films were formed on carbon steel (JIS SS400). And the pores formed by spray coating were sealed by a commercial reagent for some specimens. All of those specimens were immersed into sea water located at Marina Kawage (854-3, Chisato, Tsu, Mie Prefecture) in Ise Bay for two weeks. The depth of the specimen was two meter from sea water surface and the distance was always kept constant, since they were suspended from the floating pier. The temperature in sea water changed from 10 to 15 degrees Celsius during the immersion test. The biofouling behavior was investigated by low vacuum SEM (Hitachi Miniscope TM1000) and X-ray fluorescent analysis. When the spray coated specimens with and without sealing agents were compared, the former showed higher antifouling properties generally. Aluminium-zinc alloy spray coated films had higher antifouling property. And the anti-property decreased in this order: Al-Zn alloy spray coating > Zinc spray coating > Aluminium spray coating > Stacked chromium/nickel spray coating. Aluminium and zinc spray coating has been evaluated high conventionally for anti-biofouling in marine environment. However, the Cr/Ni spray coating showed pretty high anti-fouling property.

Identification of mothball powder composition by float tests and melting point tests.

PubMed

Tang, Ka Yuen

2018-07-01

The aim of the study was to identify the composition, as either camphor, naphthalene, or paradichlorobenzene, of mothballs in the form of powder or tiny fragments by float tests and melting point tests. Naphthalene, paradichlorobenzene and camphor mothballs were blended into powder and tiny fragments (with sizes <1/10 of the size of an intact mothball). In the float tests, the mothball powder and tiny fragments were placed in water, saturated salt solution and 50% dextrose solution (D50), and the extent to which they floated or sank in the liquids was observed. In the melting point tests, the mothball powder and tiny fragments were placed in hot water with a temperature between 53 and 80 °C, and the extent to which they melted was observed. Both the float and melting point tests were then repeated using intact mothballs. Three emergency physicians blinded to the identities of samples and solutions visually evaluated each sample. In the float tests, paradichlorobenzene powder partially floated and partially sank in all three liquids, while naphthalene powder partially floated and partially sank in water. Naphthalene powder did not sink in D50 or saturated salt solution. Camphor powder floated in all three liquids. Float tests identified the compositions of intact mothball accurately. In the melting point tests, paradichlorobenzene powder melted completely in hot water within 1 min while naphthalene powder and camphor powder did not melt. The melted portions of paradichlorobenzene mothballs were sometimes too small to be observed in 1 min but the mothballs either partially or completely melted in 5 min. Both camphor and naphthalene intact mothballs did not melt in hot water. For mothball powder, the melting point tests were more accurate than the float tests in differentiating between paradichlorobenzene and non-paradichlorobenzene (naphthalene or camphor). For intact mothballs, float tests performed better than melting point tests. Float tests can identify camphor mothballs but melting point tests cannot. We suggest melting point tests for identifying mothball powder and tiny fragments while float tests are recommended for intact mothball and large fragments.

Review on the prevalence of diabetes and risk factors and situation of disease management in floating population in China.

PubMed

Han, Kaiyi; Yao, Jingjing; Yin, Xiao; Zhao, Mei; Sun, Qiang

2017-01-01

To give a comprehensive and basic understanding of diabetes and its risk factors in floating people in China. We use "(diabetes or type 2 diabetes or chronic disease) and (floating population or employed floating population)" as the key words to search in the China academic literature database (CNKI), Wan Fang database, PubMed and Web of Science for relevant literature and extract the data about the prevalence of diabetes, relevant risk factors and disease management of the floating population in China. Twenty-one literatures are entered into analysis finally, one is English and the rest are Chinese. According to the national survey, the prevalence rate of diabetes in floating population in China was 5. 1% (95%CI, 4.9% - 5.3%), which is lower than that of the general population(11.6%,95%CI, 11.3%-11.8%),and is consistent with the results of the local surveys. The comparison result between the prevalence of floating population and that of local population in each region differs in local surveys. In addition, the prevalence of male floating population is lower than that of the female population. Finally, as the age of the population rises, so does the prevalence of diabetes. As for the risk factors of chronical diseases, the overweight rate in every region is similar but the obesity rate differs in different regions (Ningxia,26.0%;Xiangshan,14.0%), and the obesity rate of the floating population is less than half of that of the general people(4.7%,11.9%). The awareness rate, treatment rate and control rate in the floating patients differ in the regional researches, but they all can't meet the goals set by the local health departments. Compared with the general population, the prevalence of diabetes in the floating population are lower. However, Considering the growing population number and the poor disease management of the floating patients, the potential threat brought by the diabetes in floating population is imponderable. The government should establish the national surveillance system of diabetes for the floating population, strengthen the construction of the primary medical institutions, and optimize the existing funding system.

Changing Patterns of the Floating Population in China during 2000-2010*

PubMed Central

Liang, Zai; Li, Zhen; Ma, Zhongdong

2015-01-01

Using data from the 2000 and 2010 Chinese Population Censuses and applying a consistent definition of migration, this paper examines changing patterns of China's floating population during 2000-2010. We find that during the first decade of the 21st century, there have been significant changes in China's floating population, as reflected in continuing rise of interprovincial floating population and the rise of the floating population in China's western and interior regions, geographic diversification of destinations for the floating population, a major increase in interprovincial return migration, and significant improvement in education and occupational profiles among the floating population. We argue that these patterns are driven by a combination of complex domestic and international factors, including the newly released Labor Law, removal of agricultural tax, the western China development program, increased investment in education by the Chinese government, and the global financial crisis. We also discuss several challenges facing the floating population in the coming years, which include equality of educational opportunity for migrant children and adequate housing and social welfare protection for the floating population. Finally, we reflect on the future of migration research in China. PMID:26213427

14 CFR 25.753 - Main float design.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float design. 25.753 Section 25.753 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Floats and Hulls § 25.753 Main float design...

40 CFR 265.1086 - Standards: Surface impoundments.

Code of Federal Regulations, 2010 CFR

2010-07-01

... floating membrane cover in accordance with the provisions specified in paragraph (c) of this section; or (2... emissions from a surface impoundment using a floating membrane cover shall meet the requirements specified... with a floating membrane cover designed to meet the following specifications: (i) The floating membrane...

40 CFR 65.44 - External floating roof (EFR).

Code of Federal Regulations, 2013 CFR

2013-07-01

... external floating roof except for automatic bleeder vents (vacuum breaker vents) and rim space vents does... floating roof shall meet the following specifications: (i) Except for automatic bleeder vents (vacuum breaker vents) and rim space vents, each opening in the noncontact external floating roof shall provide a...

40 CFR 65.44 - External floating roof (EFR).

Code of Federal Regulations, 2014 CFR

2014-07-01

... external floating roof except for automatic bleeder vents (vacuum breaker vents) and rim space vents does... floating roof shall meet the following specifications: (i) Except for automatic bleeder vents (vacuum breaker vents) and rim space vents, each opening in the noncontact external floating roof shall provide a...

40 CFR 65.44 - External floating roof (EFR).

Code of Federal Regulations, 2012 CFR

2012-07-01

... external floating roof except for automatic bleeder vents (vacuum breaker vents) and rim space vents does... floating roof shall meet the following specifications: (i) Except for automatic bleeder vents (vacuum breaker vents) and rim space vents, each opening in the noncontact external floating roof shall provide a...

Formulation and in-vitro evaluation of floating bilayer tablet of lisinopril maleate and metoprolol tartrate.

PubMed

Ijaz, Hira; Qureshi, Junaid; Danish, Zeeshan; Zaman, Muhammad; Abdel-Daim, Mohamed; Hanif, Muhammad; Waheed, Imran; Mohammad, Imran Shair

2015-11-01

The purpose of this study was to introduce the technology for the development of rate-controlled oral drug delivery system to overcome various physiological problems. Several approaches are being used for the purpose of increasing the gastric retentive time, including floating drug delivery system. Gastric floating lisinopril maleate and metoprolol tartrate bilayer tablets were formulated by direct compression method using the sodium starch glycolate, crosscarmellose sodium for IR layer. Eudragit L100, pectin, acacia as sustained release polymers in different ratios for SR metoprolol tartrate layer and sodium bicarbonate, citric acid as gas generating agents for the floating extended release layer. The floating bilayer tablets of lisinopril maleate and metoprolol tartrate were designed to overcome the various problems associated with conventional oral dosage form. Floating tablets were evaluated for floating lag time, drug contents and in-vitro dissolution profile and different kinetic release models were applied. It was clear that the different ratios of polymers affected the drug release and floating time. L2 and M4 showed good drug release profile and floating behavior. The linear regression and model fitting showed that all formulation followed Higuchi model of drug release model except M4 that followed zero order kinetic. From the study it is evident that a promising controlled release by floating bilyer tablets of lisinopril maleate and metoprolol tartrate can be developed successfully.

Memory operations in Au nanoparticle single-electron transistors with floating gate electrodes

NASA Astrophysics Data System (ADS)

Azuma, Yasuo; Sakamoto, Masanori; Teranishi, Toshiharu; Majima, Yutaka

2016-11-01

Floating gate memory operations are demonstrated in a single-electron transistor (SET) fabricated by a chemical assembly using the Au nanogap electrodes and the chemisorbed Au nanoparticles. By applying pulse voltages to the control gate, phase shifts were clearly and stably observed both in the Coulomb oscillations and in the Coulomb diamonds. Writing and erasing operations on the floating gate memory were reproducibly observed, and the charges on the floating gate electrodes were maintained for at least 12 h. By considering the capacitance of the floating gate electrode, the number of electrons in the floating gate electrode was estimated as 260. Owing to the stability of the fabricated SET, these writing and erasing operations on the floating gate memory can be applied to reconfigurable SET circuits fabricated by a chemically assembled technique.

Geophysical monitoring of the submerged area of the Campi Flegrei caldera (Southern Italy): experiences and perspectives

NASA Astrophysics Data System (ADS)

Iannaccone, Giovanni; Guardato, Sergio; De Martino, Prospero; Donnarumma, Gian Paolo; Bobbio, Antonella; Chierici, Francesco; Pignagnoli, Luca; Beranzoli, Laura

2016-04-01

The monitoring system of the Campi Flegrei caldera is made up of a dense geophysical network of seismological and geodetic instruments with data acquired and processed at the Monitoring Center of INGV in Naples. As one third of the caldera is covered by the sea, a marine monitoring system has been operating since 2008 in the center of the gulf of Pozzuoli, where the sea depth is about 100 m at ~2.5 km from the coast. The main component of the monitoring system is CUMAS (Cabled Underwater Multidisciplinary Acquisition System), which consists of a sea floor module equipped with geophysical and oceanographic sensors (broad band seismometer, accelerometer, hydrophone, bottom pressure recorder and single point three component water-current meter) and status and control sensors. CUMAS is connected by cable to the top of an elastic beacon buoy equipped with the power supply and data transmission devices. The buoy consists of a float placed below sea level, surrounding and holding a steel pole that supports a turret structure above sea level. The pole, turret and float system are rigidly connected to the ballast on the sea bottom. Thus a GPS installed on the turret can record the vertical sea floor displacement related to the volcanic activity of the area. The GPS has operated since January 2012 with continuous acquisition lasting more than three years and has recorded a cumulative seafloor uplift of about 7-8 cm. The comparison of the pattern of the GPS buoy data with those of the land stations confirms a quasi-symmetrical vertical displacement field of the caldera area. Measurement of vertical sea floor displacement has also been obtained by the analysis of bottom pressure recorder data. These results, in conjunction with the analysis of seismic and hydrophone data, have encouraged us to extend the marine monitoring system with the deployment in the Gulf of Pozzuoli of three new similar systems. We also present preliminary results of the first few months of activity of these new systems.

40 CFR 65.44 - External floating roof (EFR).

Code of Federal Regulations, 2010 CFR

2010-07-01

... design requirements. The owner or operator who elects to control storage vessel regulated material emissions by using an external floating roof shall comply with the design requirements listed in paragraphs (a)(1) through (3) of this section. (1) The external floating roof shall be designed to float on the...

40 CFR 65.44 - External floating roof (EFR).

Code of Federal Regulations, 2011 CFR

2011-07-01

... design requirements. The owner or operator who elects to control storage vessel regulated material emissions by using an external floating roof shall comply with the design requirements listed in paragraphs (a)(1) through (3) of this section. (1) The external floating roof shall be designed to float on the...

14 CFR 29.757 - Hull and auxiliary float strength.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Hull and auxiliary float strength. 29.757 Section 29.757 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... § 29.757 Hull and auxiliary float strength. The hull, and auxiliary floats if used, must withstand the...

40 CFR 63.1063 - Floating roof requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the point of refloating the floating roof shall be continuous and shall be performed as soon as... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Floating roof requirements. 63.1063...) National Emission Standards for Storage Vessels (Tanks)-Control Level 2 § 63.1063 Floating roof...

50 CFR 679.94 - Economic data report (EDR) for the Amendment 80 sector.

Code of Federal Regulations, 2010 CFR

2010-10-01

...: NMFS, Alaska Fisheries Science Center, Economic Data Reports, 7600 Sand Point Way NE, F/AKC2, Seattle... Operation Description of code Code NMFS Alaska region ADF&G FCP Catcher/processor Floating catcher processor. FLD Mothership Floating domestic mothership. IFP Stationary Floating Processor Inshore floating...

Have Floating Rates Been a Success?

ERIC Educational Resources Information Center

Higham, David

1983-01-01

Floating exchange rates have not lived up to all expectations, but neither have they performed as badly as some critics have suggested. Examined are the impact of floating rates on balance of payments adjustment, domestic economic policy, and inflation and the claim that floating rates have displayed excessive fluctuations. (Author/RM)

Atmospheric and surface properties of Mars obtained by infrared spectroscopy on Mariner 9

NASA Technical Reports Server (NTRS)

Conrath, B.; Curran, R. J.; Hanel, R.; Kunde, V. G.; Marguire, W.; Pearl, J.; Pirraglia, J. A.; Welker, J.; Burke, T.

1972-01-01

During the eleven month operational lifetime of Mariner 9, the infrared spectroscopy experiment obtained data over a large portion of Mars. Recently obtained spectra indicate that strong seasonal variations in the water vapor distribution over both polar regions occurred. The wettest atmospheric conditions observed so far contain 20 to 30 precipitable microns of water over the north polar cap during northern spring. A low resolution pressure map is presented which covers that portion of the planet between latitudes -60 deg and +25 deg. A more detailed study of the Coprates canyon indicates that at its lowest point the canyon floor must be at least 5 km below the rim. Applications of tidal theory to temperature fields derived from the spectra indicate diurnal surface pressure fluctuations of as much as 12 percent during the great dust storm of 1971-72. Qualitative arguments based on radiative transfer calculations for model dust clouds composed of spherical quartz particles suggest that particle radii during the storm were of the order of a few microns.

Biosynthesis of Silver Nanoparticles Using Brown Marine Macroalga, Sargassum Muticum Aqueous Extract.

PubMed

Azizi, Susan; Namvar, Farideh; Mahdavi, Mahnaz; Ahmad, Mansor Bin; Mohamad, Rosfarizan

2013-12-18

Biological synthesis of nanoparticles is a relatively new emerging field of nanotechnology which has economic and eco-friendly benefits over chemical and physical processes of synthesis. In the present work, for the first time, the brown marine algae Sargassum muticum ( S. muticum ) aqueous extract was used as a reducing agent for the synthesis of nanostructure silver particles (Ag-NPs). Structural, morphological and optical properties of the synthesized nanoparticles have been characterized systematically by using FTIR, XRD, TEM and UV-Vis spectroscopy. The formation of Ag-NPs was confirmed through the presence of an intense absorption peak at 420 nm using a UV-visible spectrophotometer. A TEM image showed that the particles are spherical in shape with size ranging from 5 to 15 nm. The nanoparticles were crystalline in nature. This was confirmed by the XRD pattern. From the FTIR results, it can be seen that the reduction has mostly been carried out by sulphated polysaccharides present in S. muticum .

Biosynthesis of Silver Nanoparticles Using Brown Marine Macroalga, Sargassum Muticum Aqueous Extract

PubMed Central

Azizi, Susan; Namvar, Farideh; Mahdavi, Mahnaz; Ahmad, Mansor Bin; Mohamad, Rosfarizan

2013-01-01

Biological synthesis of nanoparticles is a relatively new emerging field of nanotechnology which has economic and eco-friendly benefits over chemical and physical processes of synthesis. In the present work, for the first time, the brown marine algae Sargassum muticum (S. muticum) aqueous extract was used as a reducing agent for the synthesis of nanostructure silver particles (Ag-NPs). Structural, morphological and optical properties of the synthesized nanoparticles have been characterized systematically by using FTIR, XRD, TEM and UV–Vis spectroscopy. The formation of Ag-NPs was confirmed through the presence of an intense absorption peak at 420 nm using a UV–visible spectrophotometer. A TEM image showed that the particles are spherical in shape with size ranging from 5 to 15 nm. The nanoparticles were crystalline in nature. This was confirmed by the XRD pattern. From the FTIR results, it can be seen that the reduction has mostly been carried out by sulphated polysaccharides present in S. muticum. PMID:28788431

Interpretation of sedimentological processes of coarse-grained deposits applying a novel combined cluster and discriminant analysis

NASA Astrophysics Data System (ADS)

Farics, Éva; Farics, Dávid; Kovács, József; Haas, János

2017-10-01

The main aim of this paper is to determine the depositional environments of an Upper-Eocene coarse-grained clastic succession in the Buda Hills, Hungary. First of all, we measured some commonly used parameters of samples (size, amount, roundness and sphericity) in a much more objective overall and faster way than with traditional measurement approaches, using the newly developed Rock Analyst application. For the multivariate data obtained, we applied Combined Cluster and Discriminant Analysis (CCDA) in order to determine homogeneous groups of the sampling locations based on the quantitative composition of the conglomerate as well as the shape parameters (roundness and sphericity). The result is the spatial pattern of these groups, which assists with the interpretation of the depositional processes. According to our concept, those sampling sites which belong to the same homogeneous groups were likely formed under similar geological circumstances and by similar geological processes. In the Buda Hills, we were able to distinguish various sedimentological environments within the area based on the results: fan, intermittent stream or marine.

Are Superplumes a Myth?

NASA Astrophysics Data System (ADS)

Steinberger, Bernhard; Conrad, Clinton

2017-04-01

Two large seismically slow lower mantle regions beneath the Pacific and Africa are sometimes referred to as "superplumes". This names evokes associations of large-scale active upwellings, however it is not clear whether these are real, or rather just regular mantle plumes occur more frequently in these regions. Here we study the implications of new results on dynamic topography, which would be associated with active upwellings, on this question. Recently, Hoggard et al. (2016) developed a detailed model of marine residual topography, after subtracting isostatic crustal topography. Combining this with results from continents, a global model can be expanded in spherical harmonics. Comparison with dynamic topography derived from mantle flow models inferred from seismic tomography (Steinberger, 2016) yields overall good agreement and similar power spectra, except at spherical harmonic degree two where mantle flow models predict about six times as much power as is inferred from observations: Mantle flow models feature two large-scale antipodal upwellings at the seismically slow regions, whereas the actual topography gives only little indication of these. We will discuss here what this discrepancy could possibly mean and how it could be resolved.

Multi-input and binary reproducible, high bandwidth floating point adder in a collective network

DOEpatents

Chen, Dong; Eisley, Noel A.; Heidelberger, Philip; Steinmacher-Burow, Burkhard

2016-11-15

To add floating point numbers in a parallel computing system, a collective logic device receives the floating point numbers from computing nodes. The collective logic devices converts the floating point numbers to integer numbers. The collective logic device adds the integer numbers and generating a summation of the integer numbers. The collective logic device converts the summation to a floating point number. The collective logic device performs the receiving, the converting the floating point numbers, the adding, the generating and the converting the summation in one pass. One pass indicates that the computing nodes send inputs only once to the collective logic device and receive outputs only once from the collective logic device.

Brain anatomy of the marine isopod Saduria entomon Linnaeus, 1758 (Valvifera, Isopoda) with special emphasis on the olfactory pathway.

PubMed

Kenning, Matthes; Harzsch, Steffen

2013-01-01

Representatives of at least six crustacean taxa managed to establish a terrestrial life style during their evolutionary history and the Oniscidea (Isopoda) are currently held as the most successfully terrestrialized malacostracan crustaceans. The brain architecture of terrestrial isopods is fairly well understood and studies on this field suggest that the evolutionary transition from sea to land in isopods coincided with a considerable size reduction and functional loss of their first pair of antennae and associated brain areas. This finding suggests that terrestrial isopods may have no or poor abilities to detect volatile substances but that their chemosensory ecology is most likely restricted to contact chemoreception. In this study, we explored how the brain of a marine isopod and particularly its olfactory system compares to that of terrestrial relatives. Using histochemical and immunohistochemical labeling, brightfield and confocal laser-scan microscopy, we show that in the marine isopod Saduria entomon aesthetascs on the first pair of antennae provide input to a well defined deutocerebrum (DC). The deutocerebral chemosensory lobes (DCL) are divided into spherical neuropil compartments, the olfactory glomeruli (og). Secondary processing areas in the lateral protocerebrum (lPC) are supplied by a thin but distinct projection neuron tract (PNT) with a contralateral connection. Hence, contrary to terrestrial Isopoda, S. entomon has at least the neuronal substrate to perceive and process olfactory stimuli suggesting the originally marine isopod lineage had olfactory abilities comparable to that of other malacostracan crustaceans.

Brain anatomy of the marine isopod Saduria entomon Linnaeus, 1758 (Valvifera, Isopoda) with special emphasis on the olfactory pathway

PubMed Central

Kenning, Matthes; Harzsch, Steffen

2013-01-01

Representatives of at least six crustacean taxa managed to establish a terrestrial life style during their evolutionary history and the Oniscidea (Isopoda) are currently held as the most successfully terrestrialized malacostracan crustaceans. The brain architecture of terrestrial isopods is fairly well understood and studies on this field suggest that the evolutionary transition from sea to land in isopods coincided with a considerable size reduction and functional loss of their first pair of antennae and associated brain areas. This finding suggests that terrestrial isopods may have no or poor abilities to detect volatile substances but that their chemosensory ecology is most likely restricted to contact chemoreception. In this study, we explored how the brain of a marine isopod and particularly its olfactory system compares to that of terrestrial relatives. Using histochemical and immunohistochemical labeling, brightfield and confocal laser-scan microscopy, we show that in the marine isopod Saduria entomon aesthetascs on the first pair of antennae provide input to a well defined deutocerebrum (DC). The deutocerebral chemosensory lobes (DCL) are divided into spherical neuropil compartments, the olfactory glomeruli (og). Secondary processing areas in the lateral protocerebrum (lPC) are supplied by a thin but distinct projection neuron tract (PNT) with a contralateral connection. Hence, contrary to terrestrial Isopoda, S. entomon has at least the neuronal substrate to perceive and process olfactory stimuli suggesting the originally marine isopod lineage had olfactory abilities comparable to that of other malacostracan crustaceans. PMID:24109435

Characterization of poly(vinyl acetate) based floating matrix tablets.

PubMed

Strübing, Sandra; Metz, Hendrik; Mäder, Karsten

2008-03-03

Floating Kollidon SR matrix tablets containing Propranolol HCl were developed and characterized with respect to drug release characteristics and floating strength. Kollidon SR was able to delay Propranolol HCl release efficiently. Drug release kinetics was evaluated using the Korsmeyer-Peppas model and found to be governed by Fickian diffusion. Tablet floating started immediately and continued for 24 h. It was possible to monitor the floating strength of the matrix devices using a simple experimental setup. Floating strength was related to Kollidon SR level with improved floating characteristics for samples with a high polymer/drug ratio. Swelling characteristics of the tablets were analyzed by applying the equation according to Therien-Aubin et al. The influence of the polymer content on swelling characteristics was found to be only marginal. Furthermore, the new method of benchtop MRI was introduced to study the water diffusion and swelling behaviour non-invasively and continuously.

Investigation of Tank 241-AW-104 Composite Floating Layer

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

Meznarich, H. K.; Bolling, S. D.; Lachut, J. S.

Seven grab samples and one field blank were taken from Tank 241-AW-104 (AW-104) on June 2, 2017, and received at 222-S Laboratory on June 5, 2017. A visible layer with brown solids was observed floating on the top of two surface tank waste samples (4AW-17-02 and 4AW 17 02DUP). The floating layer from both samples was collected, composited, and submitted for chemical analyses and solid phase characterization in order to understand the composition of the floating layer. Tributyl phosphate and tridecane were higher in the floating layer than in the aqueous phase. Density in the floating layer was slightly lowermore » than the mean density of all grab samples. Sodium nitrate and sodium carbonate were major components with a trace of gibbsite and very small size agglomerates were present in the solids of the floating layer. The supernate consisted of organics, soluble salt, and particulates.« less

33 CFR 147.815 - ExxonMobil Hoover Floating OCS Facility safety zone.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false ExxonMobil Hoover Floating OCS... HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.815 ExxonMobil Hoover Floating OCS Facility safety zone. (a) Description. The ExxonMobil Hoover Floating OCS Facility, Alaminos...

33 CFR 147.815 - ExxonMobil Hoover Floating OCS Facility safety zone.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false ExxonMobil Hoover Floating OCS... HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.815 ExxonMobil Hoover Floating OCS Facility safety zone. (a) Description. The ExxonMobil Hoover Floating OCS Facility, Alaminos...

33 CFR 147.815 - ExxonMobil Hoover Floating OCS Facility safety zone.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false ExxonMobil Hoover Floating OCS... HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.815 ExxonMobil Hoover Floating OCS Facility safety zone. (a) Description. The ExxonMobil Hoover Floating OCS Facility, Alaminos...

33 CFR 147.815 - ExxonMobil Hoover Floating OCS Facility safety zone.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false ExxonMobil Hoover Floating OCS... HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.815 ExxonMobil Hoover Floating OCS Facility safety zone. (a) Description. The ExxonMobil Hoover Floating OCS Facility, Alaminos...

33 CFR 144.01-15 - Alternates for life floats.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Alternates for life floats. 144... for life floats. (a) Approved lifeboats, approved life rafts or approved inflatable life rafts may be used in lieu of approved life floats for either all or part of the capacity required. When either...

33 CFR 144.01-5 - Location and launching of life floats.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Location and launching of life floats. 144.01-5 Section 144.01-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Location and launching of life floats. The life floats shall be distributed in accessible locations and...

33 CFR 144.01-15 - Alternates for life floats.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Alternates for life floats. 144... for life floats. (a) Approved lifeboats, approved life rafts or approved inflatable life rafts may be used in lieu of approved life floats for either all or part of the capacity required. When either...

14 CFR 23.529 - Hull and main float landing conditions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hull and main float landing conditions. 23... Water Loads § 23.529 Hull and main float landing conditions. (a) Symmetrical step, bow, and stern... directed perpendicularly to the keel line. (b) Unsymmetrical landing for hull and single float seaplanes...

46 CFR 131.870 - Life floats and buoyant apparatus.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Life floats and buoyant apparatus. 131.870 Section 131... OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.870 Life floats and buoyant apparatus. (a) The name of the vessel must be plainly marked or painted on each life float or buoyant apparatus...

33 CFR 144.01-5 - Location and launching of life floats.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Location and launching of life floats. 144.01-5 Section 144.01-5 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Location and launching of life floats. The life floats shall be distributed in accessible locations and...

46 CFR 131.870 - Life floats and buoyant apparatus.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Life floats and buoyant apparatus. 131.870 Section 131... OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.870 Life floats and buoyant apparatus. (a) The name of the vessel must be plainly marked or painted on each life float or buoyant apparatus...

46 CFR 131.870 - Life floats and buoyant apparatus.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Life floats and buoyant apparatus. 131.870 Section 131... OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.870 Life floats and buoyant apparatus. (a) The name of the vessel must be plainly marked or painted on each life float or buoyant apparatus...

46 CFR 131.870 - Life floats and buoyant apparatus.

Code of Federal Regulations, 2011 CFR

2011-10-01

... OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.870 Life floats and buoyant apparatus. (a) The name of the vessel must be plainly marked or painted on each life float or buoyant apparatus... 46 Shipping 4 2011-10-01 2011-10-01 false Life floats and buoyant apparatus. 131.870 Section 131...

46 CFR 131.870 - Life floats and buoyant apparatus.

Code of Federal Regulations, 2010 CFR

2010-10-01

... OPERATIONS Markings for Fire Equipment and Emergency Equipment § 131.870 Life floats and buoyant apparatus. (a) The name of the vessel must be plainly marked or painted on each life float or buoyant apparatus... 46 Shipping 4 2010-10-01 2010-10-01 false Life floats and buoyant apparatus. 131.870 Section 131...

77 FR 44544 - Safety Zone; Gilmerton Bridge Center Span Float-In, Elizabeth River; Norfolk, Portsmouth, and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-30

...-AA00 Safety Zone; Gilmerton Bridge Center Span Float-In, Elizabeth River; Norfolk, Portsmouth, and... withdrawing its proposed rule concerning the Gilmerton Bridge Center Span Float-in and bridge construction of... ``Safety Zone; Gilmerton Bridge Center Span Float-in, Elizabeth River; Norfolk, Portsmouth, and Chesapeake...

Airborne geoid mapping of land and sea areas of East Malaysia

NASA Astrophysics Data System (ADS)

Jamil, H.; Kadir, M.; Forsberg, R.; Olesen, A.; Isa, M. N.; Rasidi, S.; Mohamed, A.; Chihat, Z.; Nielsen, E.; Majid, F.; Talib, K.; Aman, S.

2017-02-01

This paper describes the development of a new geoid-based vertical datum from airborne gravity data, by the Department of Survey and Mapping Malaysia, on land and in the South China Sea out of the coast of East Malaysia region, covering an area of about 610,000 square kilometres. More than 107,000 km flight line of airborne gravity data over land and marine areas of East Malaysia has been combined to provide a seamless land-to-sea gravity field coverage; with an estimated accuracy of better than 2.0 mGal. The iMAR-IMU processed gravity anomaly data has been used during a 2014-2016 airborne survey to extend a composite gravity solution across a number of minor gaps on selected lines, using a draping technique. The geoid computations were all done with the GRAVSOFT suite of programs from DTU-Space. EGM2008 augmented with GOCE spherical harmonic model has been used to spherical harmonic degree N = 720. The gravimetric geoid first was tied at one tide-gauge (in Kota Kinabalu, KK2019) to produce a fitted geoid, my_geoid2017_fit_kk. The fitted geoid was offset from the gravimetric geoid by +0.852 m, based on the comparison at the tide-gauge benchmark KK2019. Consequently, orthometric height at the six other tide gauge stations was computed from HGPS Lev = hGPS - Nmy_geoid2017_.t_kk. Comparison of the conventional (HLev) and GPS-levelling heights (HGPS Lev) at the six tide gauge locations indicate RMS height difference of 2.6 cm. The final gravimetric geoidwas fitted to the seven tide gauge stations and is known as my_geoid2017_fit_east. The accuracy of the gravimetric geoid is estimated to be better than 5 cm across most of East Malaysia land and marine areas

Numerical study on aerodynamic damping of floating vertical axis wind turbines

NASA Astrophysics Data System (ADS)

Cheng, Zhengshun; Aagaard Madsen, Helge; Gao, Zhen; Moan, Torgeir

2016-09-01

Harvesting offshore wind energy resources using floating vertical axis wind turbines (VAWTs) has attracted an increasing interest in recent years. Due to its potential impact on fatigue damage, the aerodynamic damping should be considered in the preliminary design of a floating VAWT based on the frequency domain method. However, currently the study on aerodynamic damping of floating VAWTs is very limited. Due to the essential difference in aerodynamic load characteristics, the aerodynamic damping of a floating VAWT could be different from that of a floating horizontal axis wind turbine (HAWT). In this study, the aerodynamic damping of floating VAWTs was studied in a fully coupled manner, and its influential factors and its effects on the motions, especially the pitch motion, were demonstrated. Three straight-bladed floating VAWTs with identical solidity and with a blade number varying from two to four were considered. The aerodynamic damping under steady and turbulent wind conditions were estimated using fully coupled aero-hydro-servo-elastic time domain simulations. It is found that the aerodynamic damping ratio of the considered floating VAWTs ranges from 1.8% to 5.3%. Moreover, the aerodynamic damping is almost independent of the rotor azimuth angle, and is to some extent sensitive to the blade number.

Impact of anti-tacking agents on properties of gas-entrapped membrane and effervescent floating tablets.

PubMed

Kriangkrai, Worawut; Puttipipatkhachorn, Satit; Sriamornsak, Pornsak; Pongjanyakul, Thaned; Sungthongjeen, Srisagul

2014-12-01

Tackiness caused by the gas-entrapped membrane (Eudragit(®)RL 30D) was usually observed during storage of the effervescent floating tablets, leading to failure in floatation and sustained release. In this work, common anti-tacking agents (glyceryl monostearate (GMS) and talc) were used to solve this tackiness problem. The impact of anti-tacking agent on the properties of free films and corresponding floating tablets was investigated. GMS was more effective than talc in reducing tackiness of the film. Addition and increasing amount of anti-tacking agents lowered the film mechanical strength, but the coating films were still strong and flexible enough to resist the generated gas pressure inside the floating tablet. Wettability and water vapor permeability of the film decreased with increasing level of anti-tacking agents as a result of their hydrophobicity. No interaction between anti-tacking agents and polymer was observed as confirmed by Fourier transform infrared spectroscopy, powder X-ray diffractometry, and differential scanning calorimetry studies. Increasing amount of anti-tacking agents decreased time to float and tended to retard drug release of the floating tablets. Floating properties and drug release were also influenced by type of anti-tacking agents. The obtained floating tablets still possessed good floating properties and controlled drug release even though anti-tacking agent had some effects. The results demonstrated that the tackiness problem of the floating tablets could be solved by incorporating anti-tacking agent into the gas-entrapped membrane.

Characterization of airborne float coal dust emitted during continuous mining, longwall mining and belt transport.

PubMed

Shahan, M R; Seaman, C E; Beck, T W; Colinet, J F; Mischler, S E

2017-09-01

Float coal dust is produced by various mining methods, carried by ventilating air and deposited on the floor, roof and ribs of mine airways. If deposited, float dust is re-entrained during a methane explosion. Without sufficient inert rock dust quantities, this float coal dust can propagate an explosion throughout mining entries. Consequently, controlling float coal dust is of critical interest to mining operations. Rock dusting, which is the adding of inert material to airway surfaces, is the main control technique currently used by the coal mining industry to reduce the float coal dust explosion hazard. To assist the industry in reducing this hazard, the Pittsburgh Mining Research Division of the U.S. National Institute for Occupational Safety and Health initiated a project to investigate methods and technologies to reduce float coal dust in underground coal mines through prevention, capture and suppression prior to deposition. Field characterization studies were performed to determine quantitatively the sources, types and amounts of dust produced during various coal mining processes. The operations chosen for study were a continuous miner section, a longwall section and a coal-handling facility. For each of these operations, the primary dust sources were confirmed to be the continuous mining machine, longwall shearer and conveyor belt transfer points, respectively. Respirable and total airborne float dust samples were collected and analyzed for each operation, and the ratio of total airborne float coal dust to respirable dust was calculated. During the continuous mining process, the ratio of total airborne float coal dust to respirable dust ranged from 10.3 to 13.8. The ratios measured on the longwall face were between 18.5 and 21.5. The total airborne float coal dust to respirable dust ratio observed during belt transport ranged between 7.5 and 21.8.

Long-Term Observations of Ocean Biogeochemistry with Nitrate and Oxygen Sensors in Apex Profiling Floats

NASA Astrophysics Data System (ADS)

Johnson, K. S.; Coletti, L.; Jannasch, H.; Martz, T.; Swift, D.; Riser, S.

2008-12-01

Long-term, autonomous observations of ocean biogeochemical cycles are now feasible with chemical sensors in profiling floats. These sensors will enable decadal-scale observations of trends in global ocean biogeochemical cycles. Here, we focus on measurements on nitrate and dissolved oxygen. The ISUS (In Situ Ultraviolet Spectrophotometer) optical nitrate sensor has been adapted to operate in a Webb Research, Apex profiling float. The Apex float is of the type used in the Argo array and is designed for multi-year, expendable deployments in the ocean. Floats park at 1000 m depth and make 60 nitrate and oxygen measurements at depth intervals ranging from 50 m below 400 m to 5 m in the upper 100 m as they profile to the surface. All data are transmitted to shore using the Iridium telemetry system and they are available on the Internet in near-real time. Floats equipped with ISUS and an Aanderaa oxygen sensor are capable of making 280 vertical profiles from 1000 m. At a 5 day cycle time, the floats should have nearly a four year endurance. Three floats have now been deployed at the Hawaii Ocean Time series station (HOT), Ocean Station Papa (OSP) in the Gulf of Alaska and at 50 South, 30 East in the Southern Ocean. Two additional floats are designated for deployment at the Bermuda Atlantic Time Series station (BATS) and in the Drake Passage. The HOT float has made 56 profiles over 260 days and should continue operating for 3 more years. Nitrate concentrations are in excellent agreement with the long-term mean observed at HOT. No significant long-term drift in sensor response has occurred. A variety of features have been observed in the HOT nitrate data that are linked to contemporaneous changes in oxygen production and mesoscale dynamics. The impacts of these features will be briefly described. The Southern Ocean float has operated for 200 days and is now observing reinjection of nitrate into surface waters as winter mixing occurs(surface nitrate > 24 micromolar). We expect that the OSP and Southern Ocean floats will provide a quantitative measurement of the timing and magnitude of the spring bloom via the drawdown of surface nitrate. We are funded through NSF and NOPP to continue float deployments at HOT, BATS, OSP and the Southern Ocean for the next 3 years and to refine the sensor so it can be offered as a commercial option for all float users. New sensors in development for float deployments include a stable ISFET pH sensor.

33 CFR 144.01-10 - Equipment for life floats.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Equipment for life floats. 144.01... for life floats. (a) Each lifefloat shall be provided with a painter. This painter shall be a manila... 1/2 inch in diameter. (b) Each life float must have a water light of an approved automatic electric...

33 CFR 144.01-10 - Equipment for life floats.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Equipment for life floats. 144.01... for life floats. (a) Each lifefloat shall be provided with a painter. This painter shall be a manila... 1/2 inch in diameter. (b) Each life float must have a water light of an approved automatic electric...

Floating Collection in an Academic Library: An Audacious Experiment That Succeeded

ERIC Educational Resources Information Center

Coopey, Barbara; Eshbach, Barbara; Notartomas, Trish

2016-01-01

Can a floating collection thrive in a large multicampus academic research library? Floating collections have been successful in public libraries for some time, but it is uncommon for academic libraries and unheard of for a large academic library system. This article will discuss the investigation into the feasibility of a floating collection at…

33 CFR 144.01-10 - Equipment for life floats.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Equipment for life floats. 144.01... for life floats. (a) Each lifefloat shall be provided with a painter. This painter shall be a manila... 1/2 inch in diameter. (b) Each life float must have a water light of an approved automatic electric...

33 CFR 144.01-10 - Equipment for life floats.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Equipment for life floats. 144.01... for life floats. (a) Each lifefloat shall be provided with a painter. This painter shall be a manila... 1/2 inch in diameter. (b) Each life float must have a water light of an approved automatic electric...

46 CFR 117.137 - Stowage of life floats and buoyant apparatus.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Stowage of life floats and buoyant apparatus. 117.137... EQUIPMENT AND ARRANGEMENTS Survival Craft Arrangements and Equipment § 117.137 Stowage of life floats and buoyant apparatus. (a) In addition to meeting § 117.130, each life float and buoyant apparatus must be...

33 CFR 144.01-10 - Equipment for life floats.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Equipment for life floats. 144.01... for life floats. (a) Each lifefloat shall be provided with a painter. This painter shall be a manila... 1/2 inch in diameter. (b) Each life float must have a water light of an approved automatic electric...

33 CFR 147.847 - Safety Zone; BW PIONEER Floating Production, Storage, and Offloading System Safety Zone.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety Zone; BW PIONEER Floating... ZONES § 147.847 Safety Zone; BW PIONEER Floating Production, Storage, and Offloading System Safety Zone. (a) Description. The BW PIONEER, a Floating Production, Storage and Offloading (FPSO) system, is in...

33 CFR 147.815 - ExxonMobil Hoover Floating OCS Facility safety zone.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false ExxonMobil Hoover Floating OCS... Floating OCS Facility safety zone. (a) Description. The ExxonMobil Hoover Floating OCS Facility, Alaminos... (1640.4 feet) from each point on the structure's outer edge is a safety zone. (b) Regulation. No vessel...

46 CFR 117.137 - Stowage of life floats and buoyant apparatus.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Stowage of life floats and buoyant apparatus. 117.137... EQUIPMENT AND ARRANGEMENTS Survival Craft Arrangements and Equipment § 117.137 Stowage of life floats and buoyant apparatus. (a) In addition to meeting § 117.130, each life float and buoyant apparatus must be...

46 CFR 117.137 - Stowage of life floats and buoyant apparatus.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Stowage of life floats and buoyant apparatus. 117.137... EQUIPMENT AND ARRANGEMENTS Survival Craft Arrangements and Equipment § 117.137 Stowage of life floats and buoyant apparatus. (a) In addition to meeting § 117.130, each life float and buoyant apparatus must be...

Float Package and the Data Rack aboard the DC-9

NASA Technical Reports Server (NTRS)

1996-01-01

Ted Brunzie and Peter Mason observe the float package and the data rack aboard the DC-9 reduced gravity aircraft. The float package contains a cryostat, a video camera, a pump and accelerometers. The data rack displays and record the video signal from the float package on tape and stores acceleration and temperature measurements on disk.

Multi-input and binary reproducible, high bandwidth floating point adder in a collective network

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

Chen, Dong; Eisley, Noel A; Heidelberger, Philip

To add floating point numbers in a parallel computing system, a collective logic device receives the floating point numbers from computing nodes. The collective logic devices converts the floating point numbers to integer numbers. The collective logic device adds the integer numbers and generating a summation of the integer numbers. The collective logic device converts the summation to a floating point number. The collective logic device performs the receiving, the converting the floating point numbers, the adding, the generating and the converting the summation in one pass. One pass indicates that the computing nodes send inputs only once to themore » collective logic device and receive outputs only once from the collective logic device.« less

Triple acting radial seal

DOEpatents

Ebert, Todd A [West Palm Beach, FL; Carella, John A [Jupiter, FL

2012-03-13

A triple acting radial seal used as an interstage seal assembly in a gas turbine engine, where the seal assembly includes an interstage seal support extending from a stationary inner shroud of a vane ring, the interstage seal support includes a larger annular radial inward facing groove in which an outer annular floating seal assembly is secured for radial displacement, and the outer annular floating seal assembly includes a smaller annular radial inward facing groove in which an inner annular floating seal assembly is secured also for radial displacement. A compliant seal is secured to the inner annular floating seal assembly. The outer annular floating seal assembly encapsulates the inner annular floating seal assembly which is made from a very low alpha material in order to reduce thermal stress.

[Analysis of the distribution of VOCs concentration field with oil static breathing loss in internal floating roof tank].

PubMed

Wu, Hong-Zhang; Huang, Wei-Qiu; Yang, Guang; Zhao, Chen-Lu; Wang, Ying-Xia; Cai, Dao-Fei

2013-12-01

Internal floating roof tank has the advantages of external floating roof tank and fixed roof tank and has its own evaporation loss properties. The influences of volatile organic compounds (VOCs) distribution gradient, molecular diffusion, thermal diffusion and forced convection on the evaporation loss of oil were studied in the space of the homemade platform of an internal floating roof tank. The results showed that thermal diffusion with temperature change was the main cause for the static loss in the internal floating roof tank. On this basis, there were some measures for reduction of the evaporation loss and formulas to calculate the evaporation loss of the internal floating roof tank in this research.

Enhancement of aptamer immobilization using egg shell-derived nano-sized spherical hydroxyapatite for thrombin detection in neuroclinic.

PubMed

Derkus, Burak; Arslan, Yavuz Emre; Emregul, Kaan C; Emregul, Emel

2016-09-01

In the present study, we describe the sonochemical isolation of nano-sized spherical hydroxyapatite (nHA) from egg shell and application towards thrombin aptasensing. In addition to the sonochemical method, two conventional methods present in literature were carried out to perform a comparative study. Various analysis methods including Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Energy-Dispersive Analysis of X-Rays (EDAX), and Thermal Gravimetric Analysis (TGA) have been applied for the characterization of nHA and its nanocomposite with marine-derived collagen isolated from Rhizostoma pulmo jellyfish. TEM micrographs revealed the sonochemically synthesized nHA nanoparticles to have a unique porous spherical shape with a diameter of approximately 60-80nm when compared to hydroxyapatite nanoparticles synthesized using the other two methods which had a typical needle shaped morphology. EDAX, XRD and FTIR results demonstrated that the obtained patterns belonged to hydroxyapatite. Electrochemical impedance spectroscopy (EIS) is the main analyzing technique of the developed thrombin aptasensor. The proposed aptasensor has a detection limit of 0.25nM thrombin. For clinical application of the developed aptasensor, thrombin levels in blood and cerebrospinal fluid (CSF) samples obtained from patients with Multiple Sclerosis, Myastenia Gravis, Epilepsy, Parkinson, polyneuropathy and healthy donors were analyzed using both the aptasensor and commercial ELISA kit. The results showed that the proposed system is a promising candidate for clinical analysis of thrombin. Copyright © 2016 Elsevier B.V. All rights reserved.

Improving mercury flux chamber measurements over water surface.

PubMed

Lanzillotra, E; Ceccarini, C; Ferrara, R

2003-07-01

A modified floating flux chamber was designed and used to measure mercury evasional fluxes in a coastal area of the Mediterranean Sea in different meteo-marine conditions during the hours of maximum insolation (PAR intensity 360-430 W m(-2)) in the summer season. The chamber has been modified providing a flap at the inlet port preventing the back-flow of air from the interior of the chamber. Results demonstrate that the modified flux chamber gives flux values noticeably higher both in rippled sea conditions (mean value 7.88 +/- 1.45 ng m(-2) h(-1)) and in rough sea conditions (mean value 21.71 +/- 2.17 ng m(-2) h(-1)) with respect to those obtained by using the unmodified chamber (respectively 5.23 +/- 0.67 and 14.15 +/- 1.03 ng m(-2) h(-1)).

Decadally resolved Lateglacial radiocarbon evidence from New Zealand kauri

NASA Astrophysics Data System (ADS)

Hogg, Alan; Southon, John; Turney, Chris; Palmer, Jonathan; Bronk Ramsey, Christopher; Fenwick, Pavla; Boswijk, Gretel; Büntgen, Ulf; Friedrich, Michael; Helle, Gerhard; Hughen, Konrad; Jones, Richard; Kromer, Bernd; Noronha, Alexandra; Reinig, Frederick; Reynard, Linda; Staff, Richard; Wacker, Lukas

2017-04-01

The Last Glacial-Interglacial Transition (LGIT; 15,000 - 11,000 cal BP) was characterised by complex spatiotemporal patterns of climate change, with numerous studies requiring accurate chronological control to decipher leads from lags in global palaeoclimatic, -environmental and archaeological records. However, close scrutiny of the few available tree-ring chronologies and radiocarbon-dated sequences composing the IntCal13 radiocarbon (14C) calibration curve, indicates significant weakness in 14C calibration across key periods of the LGIT. Here, we present a decadally-resolved atmospheric 14C record derived from New Zealand kauri spanning Greenland Stadial 1 (GS-1; 12,900 - 11,650 cal BP). Two floating kauri 14C time series, curve-matched to IntCal13, serve as a radiocarbon backbone through GS-1. Floating Northern Hemisphere (NH) 14C datasets are matched against the new kauri data, forming a robust NH 14C time series to 14,200 cal BP. Our results show that IntCal13 is questionable from 12,200 - 11,900 cal BP and the 10,400 BP 14C plateau is approximately five decades too short. By precisely aligning Southern and Northern Hemisphere tree-ring 14C records with marine 14C sequences, we document two relatively short periods of North Atlantic Meridional Overturning Circulation (AMOC) collapse during GS-1. Hence, sustained North Atlantic cooling across GS-1 was not driven by a prolonged AMOC reduction but was probably due to an equatorward migration of the Polar Front.

Experimental investigation on the hydrodynamic performance of a wave energy converter

NASA Astrophysics Data System (ADS)

Zheng, Xiong-bo; Ma, Yong; Zhang, Liang; Jiang, Jin; Liu, Heng-xu

2017-06-01

Wave energy is an important type of marine renewable energy. A wave energy converter (WEC) moored with two floating bodies was developed in the present study. To analyze the dynamic performance of the WEC, an experimental device was designed and tested in a tank. The experiment focused on the factors which impact the motion and energy conversion performance of the WEC. Dynamic performance was evaluated by the relative displacements and velocities of the oscillator and carrier which served as the floating bodies of WEC. Four factors were tested, i.e. wave height, wave period, power take-off (PTO) damping, and mass ratio ( R M) of the oscillator and carrier. Experimental results show that these factors greatly affect the energy conversion performance, especially when the wave period matches R M and PTO damping. According to the results, we conclude that: (a) the maximization of the relative displacements and velocities leads to the maximization of the energy conversion efficiency; (b) the larger the wave height, the higher the energy conversion efficiency will be; (c) the relationships of energy conversion efficiency with wave period, PTO damping, and R M are nonlinear, but the maximum efficiency is obtained when these three factors are optimally matched. Experimental results demonstrated that the energy conversion efficiency reached the peak at 28.62% when the wave height was 120 mm, wave period was 1.0 s, R M was 0.21, and the PTO damping was corresponding to the resistance of 100 Ω.

Attachment strength of the subtidal seaweed Sargassum horneri (Turner) C. Agardh varies among development stages and depths.

PubMed

Xu, Min; Sakamoto, Shingo; Komatsu, Teruhisa

2016-01-01

Sargassum horneri is one of the most important contributors to the rafts of floating seaweed in the waters off the coasts of northeastern Asia. These rafts serve as spawning and nursery grounds for many marine organisms, including Japanese saury and yellowtail. Thus, the details of the attachment/detachment mechanisms of S. horneri are of commercial significance for the aquaculture industry. Here, we describe variations in the attachment strength of S. horneri as it relates to its developmental stage and depth along a bottom gradient. We measured the attachment strength/dislodgement force of S. horneri samples with holdfast detachment in Shidagaura Cove, Shimoda, Japan, from December 2014 to May 2015. After we had determined the dislodgement forces required to detach thalli from the substratum (using a spring scale device) in the field, we transferred released individuals to the laboratory and measured selected morphological traits. Attachment strength was linearly related to the holdfast basal area when thalli were immature (prior to mid-March), but not when they were mature (mid-March to May). Thus, attachment strength was maintained through the reproductive phase and declined thereafter, allowing released thalli to join the drifting raft community. Rafting may be a mechanism by which the species expands its distribution range, as floating thalli continuing to shed germlings that are able to recruit when suitable habitat is encountered. Attachment strengths were greater in the shallows than in deeper water, reflecting the differences in wave forces experienced at different depths.

Coupled ice sheet-ocean modelling to investigate ocean driven melting of marine ice sheets in Antarctica

NASA Astrophysics Data System (ADS)

Jong, Lenneke; Gladstone, Rupert; Galton-Fenzi, Ben

2017-04-01

Ocean induced melting below the ice shelves of marine ice sheets is a major source of uncertainty for predictions of ice mass loss and Antarctica's resultant contribution to future sea level rise. The floating ice shelves provide a buttressing force against the flow of ice across the grounding line into the ocean. Thinning of these ice shelves due to an increase in melting reduces this force and can lead to an increase in the discharge of grounded ice. Fully coupled modelling of ice sheet-ocean interactions is key to improving understanding the influence of the Southern ocean on the evolution of the Antarctic ice sheet, and to predicting its future behaviour under changing climate conditions. Coupling of ocean and ice sheet models is needed to provide more realistic melt rates at the base of ice shelves and hence make better predictions of the behaviour of the grounding line and the shape of the ice-shelf cavity as the ice sheet evolves. The Framework for Ice Sheet - Ocean Coupling (FISOC) has been developed to provide a flexible platform for performing coupled ice sheet - ocean modelling experiments. We present preliminary results using FISOC to couple the Regional Ocean Modelling System (ROMS) with Elmer/Ice in idealised experiments Marine Ice Sheet-Ocean Model Intercomparison Project (MISOMIP). These experiments use an idealised geometry motivated by that of Pine Island glacier and the adjacent Amundsen Sea in West Antarctica, a region which has shown shown signs of thinning ice and grounding line retreat.

Development and Characterization of Novel Floating-Mucoadhesive Tablets Bearing Venlafaxine Hydrochloride.

PubMed

Misra, Raghvendra; Bhardwaj, Peeyush

2016-01-01

The present investigation is concerned about the development of floating bioadhesive drug delivery system of venlafaxine hydrochloride which after oral administration exhibits a unique combination of floating and bioadhesion to prolong gastric residence time and increase drug bioavailability within the stomach. The floating bioadhesive tablets were prepared by the wet granulation method using different ratios of hydroxypropyl methyl cellulose (HPMC K4MCR) and Carbopol 934PNF as polymers. Sodium bicarbonate (NaHCO3) and citric acid were used as gas (CO2) generating agents. Tablets were characterized for floating properties, in vitro drug release, detachment force, and swelling index. The concentration of hydroxypropyl methyl cellulose and Carbopol 934PNF significantly affects the in vitro drug release, floating properties, detachment force, and swelling properties of the tablets. The optimized formulation showed the floating lag time 72 ± 2.49 seconds and duration of floating 24.50 ± 0.74 hr. The in vitro release studies and floating behavior were studied in simulated gastric fluid (SGF) at pH 1.2. Different drug release kinetics models were also applied. The in vitro drug release from tablets was sufficiently sustained (more than 18 hr) and the Fickian transports of the drug from the tablets were confirmed. The radiological evidence suggests that the tablets remained buoyant and altered position in the stomach of albino rabbit and mean gastric residence time was prolonged (more than > 6 hr).

Floating Solar Photovoltaics Gaining Ground | State, Local, and Tribal

Science.gov Websites

Gaining Ground January 24, 2017 by Alison Holm Floating solar photovoltaic (PV) systems, so-called flotovoltaics (a trademarked term) or floating solar, represent an emerging application in which PV panels are sited on bodies of water. The PV panel technology used for floating solar applications is very similar

Impact of floating population on the epidemic of tuberculosis: a spatial analysis

NASA Astrophysics Data System (ADS)

Jia, Zhongwei; He, Xiaoxin; Zhao, Wenjuan; An, Yansheng; Cao, Wuchun; Li, Xiaowen

2007-06-01

According to the report issued by the Health Bureau of Beijing that the number of newly registered active pulmonary tuberculosis cases in floating population exceeded half of that in registered permanent residence in 2006. More attention has been paid to the tuberculosis of floating population. Materials and methods: The population data included in the studied was reported by the Beijing Police Bureau in 2004, and the case source from 2004 to 2006 was provided by Beijing Research Institute for TB Control. Two GIS-based methods have been used to detect the hot spots of tuberculosis in 18 districts of Beijing. Results: The distributions of hot spots of tuberculosis in Beijing are significantly associated with that of floating people. Most likely cluster from all population matches with those from floating population, which is stable from 2004 to 2006. Conclusion: The spatial analytical results indicated that the floating population has a drastic influence on the epidemic of tuberculosis in Beijing. The tuberculosis control measures should incorporate the effect of floating population.

50 CFR 86.13 - What is boating infrastructure?

Code of Federal Regulations, 2011 CFR

2011-10-01

... (CONTINUED) FINANCIAL ASSISTANCE-WILDLIFE SPORT FISH RESTORATION PROGRAM BOATING INFRASTRUCTURE GRANT (BIG...) Floating docks and fixed piers; (g) Floating and fixed breakwaters; (h) Dinghy docks (floating or fixed...

Macrofouling communities and the degradation of plastic bags in the sea: an in situ experiment

PubMed Central

Petermann, Jana S.; Lott, Christian; Weber, Miriam

2017-01-01

The increasing amount of plastic littered into the sea may provide a new substratum for benthic organisms. These marine fouling communities on plastic have not received much scientific attention. We present, to our knowledge, the first comprehensive analysis of their macroscopic community composition, their primary production and the polymer degradation comparing conventional polyethylene (PE) and a biodegradable starch-based plastic blend in coastal benthic and pelagic habitats in the Mediterranean Sea. The biomass of the fouling layer increased significantly over time and all samples became heavy enough to sink to the seafloor. The fouling communities, consisting of 21 families, were distinct between habitats, but not between polymer types. Positive primary production was measured in the pelagic, but not in the benthic habitat, suggesting that large accumulations of floating plastic could pose a source of oxygen for local ecosystems, as well as a carbon sink. Contrary to PE, the biodegradable plastic showed a significant loss of tensile strength and disintegrated over time in both habitats. These results indicate that in the marine environment, biodegradable polymers may disintegrate at higher rates than conventional polymers. This should be considered for the development of new materials, environmental risk assessment and waste management strategies. PMID:29134070

Quantifying dispersal from hydrothermal vent fields in the western Pacific Ocean

PubMed Central

Mitarai, Satoshi; Watanabe, Hiromi; Nakajima, Yuichi; Shchepetkin, Alexander F.; McWilliams, James C.

2016-01-01

Hydrothermal vent fields in the western Pacific Ocean are mostly distributed along spreading centers in submarine basins behind convergent plate boundaries. Larval dispersal resulting from deep-ocean circulations is one of the major factors influencing gene flow, diversity, and distributions of vent animals. By combining a biophysical model and deep-profiling float experiments, we quantify potential larval dispersal of vent species via ocean circulation in the western Pacific Ocean. We demonstrate that vent fields within back-arc basins could be well connected without particular directionality, whereas basin-to-basin dispersal is expected to occur infrequently, once in tens to hundreds of thousands of years, with clear dispersal barriers and directionality associated with ocean currents. The southwest Pacific vent complex, spanning more than 4,000 km, may be connected by the South Equatorial Current for species with a longer-than-average larval development time. Depending on larval dispersal depth, a strong western boundary current, the Kuroshio Current, could bridge vent fields from the Okinawa Trough to the Izu-Bonin Arc, which are 1,200 km apart. Outcomes of this study should help marine ecologists estimate gene flow among vent populations and design optimal marine conservation plans to protect one of the most unusual ecosystems on Earth. PMID:26929376

Control of parasites in cultured marine finfishes in Southeast Asia--an overview.

PubMed

Seng, L T

1997-10-01

Mariculture in Southeast Asia began in the 1970s and expanded rapidly during the 1980s, with the commercial hatchery production of the seabass Lates calcarifer. Other important cultured species were Epinephelus coioides, Epinephelus malabaricus, Lutjanus johni, and Lutjanus argentimaculatus. Intensification in the polyculture of these species and the large-scale international movement of fingerlings or juveniles, as well as the rapid expansion and concentration of fish farms, have caused severe problems resulting from parasitic infections. Infections in maricultured fish are predominantly caused by monoxenous parasites, in particular the capsalid and diplectanid monogeneans. Heteroxenous blood parasites also successfully maintained transmission in the culture system despite their requirement for an intermediate host. Prophylactic chemical treatments helped to reduce parasitic infection but did not eliminate them and once introduced into the floating netcage culture system, these parasites managed to maintain their transmission successfully. Despite the current lack of information regarding the biology of many parasites affecting cultured marine fishes, it nevertheless is possible to develop methodologies to produce an integrated health management system specifically designed to the needs of the mariculture practiced in the Southeast Asian region. This system is important and should include a sequence of prophylaxes, adequate nutrition, sanitation, immunization and an effective system of marketing for farmed fishes.

Quantifying dispersal from hydrothermal vent fields in the western Pacific Ocean.

PubMed

Mitarai, Satoshi; Watanabe, Hiromi; Nakajima, Yuichi; Shchepetkin, Alexander F; McWilliams, James C

2016-03-15

Hydrothermal vent fields in the western Pacific Ocean are mostly distributed along spreading centers in submarine basins behind convergent plate boundaries. Larval dispersal resulting from deep-ocean circulations is one of the major factors influencing gene flow, diversity, and distributions of vent animals. By combining a biophysical model and deep-profiling float experiments, we quantify potential larval dispersal of vent species via ocean circulation in the western Pacific Ocean. We demonstrate that vent fields within back-arc basins could be well connected without particular directionality, whereas basin-to-basin dispersal is expected to occur infrequently, once in tens to hundreds of thousands of years, with clear dispersal barriers and directionality associated with ocean currents. The southwest Pacific vent complex, spanning more than 4,000 km, may be connected by the South Equatorial Current for species with a longer-than-average larval development time. Depending on larval dispersal depth, a strong western boundary current, the Kuroshio Current, could bridge vent fields from the Okinawa Trough to the Izu-Bonin Arc, which are 1,200 km apart. Outcomes of this study should help marine ecologists estimate gene flow among vent populations and design optimal marine conservation plans to protect one of the most unusual ecosystems on Earth.

SAR observation and model tracking of an oil spill event in coastal waters.

PubMed

Cheng, Yongcun; Li, Xiaofeng; Xu, Qing; Garcia-Pineda, Oscar; Andersen, Ole Baltazar; Pichel, William G

2011-02-01

Oil spills are a major contributor to marine pollution. The objective of this work is to simulate the oil spill trajectory of oil released from a pipeline leaking in the Gulf of Mexico with the GNOME (General NOAA Operational Modeling Environment) model. The model was developed by NOAA (National Oceanic and Atmospheric Administration) to investigate the effects of different pollutants and environmental conditions on trajectory results. Also, a Texture-Classifying Neural Network Algorithm (TCNNA) was used to delineate ocean oil slicks from synthetic aperture radar (SAR) observations. During the simulation, ocean currents from NCOM (Navy Coastal Ocean Model) outputs and surface wind data measured by an NDBC (National Data Buoy Center) buoy are used to drive the GNOME model. The results show good agreement between the simulated trajectory of the oil spill and synchronous observations from the European ENVISAT ASAR (Advanced Synthetic Aperture Radar) and the Japanese ALOS (Advanced Land Observing Satellite) PALSAR (Phased Array L-band Synthetic Aperture Radar) images. Based on experience with past marine oil spills, about 63.0% of the oil will float and 18.5% of the oil will evaporate and disperse. In addition, the effects from uncertainty of ocean currents and the diffusion coefficient on the trajectory results are also studied. Copyright © 2010 Elsevier Ltd. All rights reserved.

Study on high power ultraviolet laser oil detection system

NASA Astrophysics Data System (ADS)

Jin, Qi; Cui, Zihao; Bi, Zongjie; Zhang, Yanchao; Tian, Zhaoshuo; Fu, Shiyou

2018-03-01

Laser Induce Fluorescence (LIF) is a widely used new telemetry technology. It obtains information about oil spill and oil film thickness by analyzing the characteristics of stimulated fluorescence and has an important application in the field of rapid analysis of water composition. A set of LIF detection system for marine oil pollution is designed in this paper, which uses 355nm high-energy pulsed laser as the excitation light source. A high-sensitivity image intensifier is used in the detector. The upper machine sends a digital signal through a serial port to achieve nanoseconds range-gated width control for image intensifier. The target fluorescence spectrum image is displayed on the image intensifier by adjusting the delay time and the width of the pulse signal. The spectral image is coupled to CCD by lens imaging to achieve spectral display and data analysis function by computer. The system is used to detect the surface of the floating oil film in the distance of 25m to obtain the fluorescence spectra of different oil products respectively. The fluorescence spectra of oil products are obvious. The experimental results show that the system can realize high-precision long-range fluorescence detection and reflect the fluorescence characteristics of the target accurately, with broad application prospects in marine oil pollution identification and oil film thickness detection.

Bacterial Community Profiling of Plastic Litter in the Belgian Part of the North Sea.

PubMed

De Tender, Caroline A; Devriese, Lisa I; Haegeman, Annelies; Maes, Sara; Ruttink, Tom; Dawyndt, Peter

2015-08-18

Bacterial colonization of marine plastic litter (MPL) is known for over four decades. Still, only a few studies on the plastic colonization process and its influencing factors are reported. In this study, seafloor MPL was sampled at different locations across the Belgian part of the North Sea to study bacterial community structure using 16S metabarcoding. These marine plastic bacterial communities were compared with those of sediment and seawater, and resin pellets sampled on the beach, to investigate the origin and uniqueness of plastic bacterial communities. Plastics display great variation of bacterial community composition, while each showed significant differences from those of sediment and seawater, indicating that plastics represent a distinct environmental niche. Various environmental factors correlate with the diversity of MPL bacterial composition across plastics. In addition, intrinsic plastic-related factors such as pigment content may contribute to the differences in bacterial colonization. Furthermore, the differential abundance of known primary and secondary colonizers across the various plastics may indicate different stages of bacterial colonization, and may confound comparisons of free-floating plastics. Our studies provide insights in the factors that shape plastic bacterial colonization and shed light on the possible role of plastic as transport vehicle for bacteria through the aquatic environment.

Collective Behavior of Camphor Floats Migrating on the Water Surface

NASA Astrophysics Data System (ADS)

Nishimori, Hiraku; Suematsu, Nobuhiko J.; Nakata, Satoshi

2017-10-01

As simple and easily controllable objects among various self-propelled particles, camphor floats on the water surface have been widely recognized. In this paper, we introduce characteristic behaviors and discuss the background mechanism of camphor floats on water, both in isolated and non-isolated conditions. In particular, we focus on: (i) the transition of dynamical characters through bifurcations exhibited by systems with small number of camphor floats and (ii) the emergence of a rich variety of complex dynamics observed in systems with large number camphor floats, and attempt to elucidate these phenomena through mathematical modeling as well as experimental analysis. Finally, we discuss the connection of the dynamics of camphor floats to that of a wider class of complex and sophisticated dynamics exhibited by various types of self-propelled particles.

Modeling International Space Station (ISS) Floating Potentials

NASA Technical Reports Server (NTRS)

Ferguson, Dale C.; Gardner, Barbara

2002-01-01

The floating potential of the International Space Station (ISS) as a function of the electron current collection of its high voltage solar array panels is derived analytically. Based on Floating Potential Probe (FPP) measurements of the ISS potential and ambient plasma characteristics, it is shown that the ISS floating potential is a strong function of the electron temperature of the surrounding plasma. While the ISS floating potential has so far not attained the pre-flight predicted highly negative values, it is shown that for future mission builds, ISS must continue to provide two-fault tolerant arc-hazard protection for astronauts on EVA.

Environment parameters and basic functions for floating-point computation

NASA Technical Reports Server (NTRS)

Brown, W. S.; Feldman, S. I.

1978-01-01

A language-independent proposal for environment parameters and basic functions for floating-point computation is presented. Basic functions are proposed to analyze, synthesize, and scale floating-point numbers. The model provides a small set of parameters and a small set of axioms along with sharp measures of roundoff error. The parameters and functions can be used to write portable and robust codes that deal intimately with the floating-point representation. Subject to underflow and overflow constraints, a number can be scaled by a power of the floating-point radix inexpensively and without loss of precision. A specific representation for FORTRAN is included.

On a new species of Pavlova (Prymnesiophyceae) from China

NASA Astrophysics Data System (ADS)

Tseng, C. K.; Jiaofen, Chen; Zhefu, Zhang

1992-03-01

Pavlova viridis sp. nov. is described on the basis of light and electron microscope observations. The material was collected from the coast of haiyang county of Shandong, China. It is characterized by 1) yellowish green to green chloroplast, 2) rudimentary short flagellum 0.3 μm long and hook-shaped, 3) long flagellum with small spherical knob-scales, 4) absence of pyrenoid and stigma, and 5) marine habitat. This new species and P. salina seem to be most closely related to each other but their colour, the insertion of their three appendages, the shape of their knob scales, and their cell periplasts are quite different from one another.

Enhancements to PCRSM.

DTIC Science & Technology

1991-03-01

the A parameters; yhatf, to calculate the y-hat statistics; ssrf, to calculate the uncorrected SSR; sstof, to calculate the uncorrected SSTO ; matmulmm...DEGREES OF FREEDOM * int sstocdf, ssrcdf, ssecdf; float ssr, ssto , sse; /* SUM OF SQUARES * float ssrc, sstoc, ssec; float insr, insto, inse; float...Y-HAT STATSISTICS * yhatf(x,beta,stats,n,n); /* CALCULATE UNCORRECTED SSR * ssrf(beta, x, y, mn, n, ss); ssr = ss[l][l]; /* CALCULATE UNCORRECTED SSTO

46 CFR 160.077-31 - PFD Marking.

Code of Federal Regulations, 2013 CFR

2013-10-01

... RISK OF DEATH BY DROWNING —YOU MAY HAVE TO INFLATE THIS PFD TO FLOAT. —TRY THIS PFD IN THE WATER EACH SEASON TO SEE IF IT WILL FLOAT YOU WITHOUT INFLATION. —CHOOSE THE RIGHT SIZE PFD AND WEAR IT—FASTEN ALL... TO FLOAT. —TRY THIS PFD IN THE WATER EACH SEASON TO SEE IF IT WILL FLOAT YOU WITHOUT INFLATION. —[For...

46 CFR 160.077-31 - PFD Marking.

Code of Federal Regulations, 2012 CFR

2012-10-01

... RISK OF DEATH BY DROWNING —YOU MAY HAVE TO INFLATE THIS PFD TO FLOAT. —TRY THIS PFD IN THE WATER EACH SEASON TO SEE IF IT WILL FLOAT YOU WITHOUT INFLATION. —CHOOSE THE RIGHT SIZE PFD AND WEAR IT—FASTEN ALL... TO FLOAT. —TRY THIS PFD IN THE WATER EACH SEASON TO SEE IF IT WILL FLOAT YOU WITHOUT INFLATION. —[For...

46 CFR 160.077-31 - PFD Marking.

Code of Federal Regulations, 2014 CFR

2014-10-01

... RISK OF DEATH BY DROWNING —YOU MAY HAVE TO INFLATE THIS PFD TO FLOAT. —TRY THIS PFD IN THE WATER EACH SEASON TO SEE IF IT WILL FLOAT YOU WITHOUT INFLATION. —CHOOSE THE RIGHT SIZE PFD AND WEAR IT—FASTEN ALL... TO FLOAT. —TRY THIS PFD IN THE WATER EACH SEASON TO SEE IF IT WILL FLOAT YOU WITHOUT INFLATION. —[For...

46 CFR 160.077-31 - PFD Marking.

Code of Federal Regulations, 2011 CFR

2011-10-01

... RISK OF DEATH BY DROWNING —YOU MAY HAVE TO INFLATE THIS PFD TO FLOAT. —TRY THIS PFD IN THE WATER EACH SEASON TO SEE IF IT WILL FLOAT YOU WITHOUT INFLATION. —CHOOSE THE RIGHT SIZE PFD AND WEAR IT—FASTEN ALL... TO FLOAT. —TRY THIS PFD IN THE WATER EACH SEASON TO SEE IF IT WILL FLOAT YOU WITHOUT INFLATION. —[For...

The Affect of Mobile Performance Support Devices on Anxiety and Self-Efficacy of Hospital Float Staff

ERIC Educational Resources Information Center

Riley McKee, Megan

2012-01-01

Floating describes the act of staff moving from one unit to another based on the needs of the patients in a hospital. Many staff who float to different units express negative feelings, including anxiety and lack in self-efficacy. However, floating is both an economical and efficient method to use staff across the hospital, especially with current…

Are floating algal mats a refuge from hypoxia for estuarine invertebrates?

PubMed Central

Knysh, Kyle M.; Theriault, Emma F.; Pater, Christina C.; Courtenay, Simon C.; van den Heuvel, Michael R.

2017-01-01

Eutrophic aquatic habitats are characterized by the proliferation of vegetation leading to a large standing biomass that upon decomposition may create hypoxic (low-oxygen) conditions. This is indeed the case in nutrient impacted estuaries of Prince Edward Island, Canada, where macroalgae, from the genus Ulva, form submerged ephemeral mats. Hydrological forces and gases released from photosynthesis and decomposition lead to these mats occasionally floating to the water’s surface, henceforth termed floating mats. Here, we explore the hypothesis that floating mats are refugia during periods of sustained hypoxia/anoxia and examine how the invertebrate community responds to it. Floating mats were not always present, so in the first year (2013) sampling was attempted monthly and limited to when both floating and submerged mats occurred. In the subsequent year sampling was weekly, but at only one estuary due to logistical constraints from increased sampling frequency, and was not limited to when both mat types occurred. Water temperature, salinity, and pH were monitored bi-weekly with dissolved oxygen concentration measured hourly. The floating and submerged assemblages shared many of the same taxa but were statistically distinct communities; submerged mats tended to have a greater proportion of benthic animals and floating mats had more mobile invertebrates and insects. In 2014, sampling happened to occur in the weeks before the onset of anoxia, during 113 consecutive hours of sustained anoxia, and for four weeks after normoxic conditions returned. The invertebrate community on floating mats appeared to be unaffected by anoxia, indicating that these mats may be refugia during times of oxygen stress. Conversely, there was a dramatic decrease in animal abundances that remained depressed on submerged mats for two weeks. Cluster analysis revealed that the submerged mat communities from before the onset of anoxia and four weeks after anoxia were highly similar to each other, indicating recovery. When mobile animals were considered alone, there was an exponential relationship between the percentage of animals on floating mats, relative to the total number on both mat types, and hypoxia. The occupation of floating mats by invertebrates at all times, and their dominance there during hypoxia/anoxia, provides support for the hypothesis that floating mats are refugia. PMID:28348927

Characterization of airborne float coal dust emitted during continuous mining, longwall mining and belt transport

PubMed Central

Shahan, M.R.; Seaman, C.E.; Beck, T.W.; Colinet, J.F.; Mischler, S.E.

2017-01-01

Float coal dust is produced by various mining methods, carried by ventilating air and deposited on the floor, roof and ribs of mine airways. If deposited, float dust is re-entrained during a methane explosion. Without sufficient inert rock dust quantities, this float coal dust can propagate an explosion throughout mining entries. Consequently, controlling float coal dust is of critical interest to mining operations. Rock dusting, which is the adding of inert material to airway surfaces, is the main control technique currently used by the coal mining industry to reduce the float coal dust explosion hazard. To assist the industry in reducing this hazard, the Pittsburgh Mining Research Division of the U.S. National Institute for Occupational Safety and Health initiated a project to investigate methods and technologies to reduce float coal dust in underground coal mines through prevention, capture and suppression prior to deposition. Field characterization studies were performed to determine quantitatively the sources, types and amounts of dust produced during various coal mining processes. The operations chosen for study were a continuous miner section, a longwall section and a coal-handling facility. For each of these operations, the primary dust sources were confirmed to be the continuous mining machine, longwall shearer and conveyor belt transfer points, respectively. Respirable and total airborne float dust samples were collected and analyzed for each operation, and the ratio of total airborne float coal dust to respirable dust was calculated. During the continuous mining process, the ratio of total airborne float coal dust to respirable dust ranged from 10.3 to 13.8. The ratios measured on the longwall face were between 18.5 and 21.5. The total airborne float coal dust to respirable dust ratio observed during belt transport ranged between 7.5 and 21.8. PMID:28936001

SOCCOM Biogeochemical Profiling Floats: Representativeness and Deployment Strategies Utilizing GO-SHIP/Argo Observations and SOSE/Hycom Model Output

NASA Astrophysics Data System (ADS)

Talley, L. D.; Riser, S.; Johnson, K. S.; Wang, J.; Kamenkovich, I. V.; Rosso, I.; Mazloff, M. R.; Ogle, S.; Sarmiento, J. L.

2016-12-01

Biogeochemical profiling floats are being deployed in the Southern Ocean south of 30°S, including within the seasonal sea ice zone, as part of the SOCCOM project. The floats carry oxygen, nitrate, pH, fluorescence and backscatter sensors, in addition to standard T/S measurements that contribute to the Argo program. The total array size over the expected 6 years of deployment will be 180 to 200 floats. At the conclusion of Year 2 (2015-2016), 58 floats had been deployed and 50 were still active (see figure from http://soccom.princeton.edu). In order to calibrate the biogeochemical sensors using shipboard measurements, deployment takes place from research ships. As the ship tracks are dictated by other programs, care is taken prior to deployment to maximize the probability that the floats sample varied oceanographic regimes, and that all important regimes present along a deployment track are seeded with at least one float. Prior GO-SHIP hydrographic sections are used to locate water mass regimes that are targeted for deployments, yielding a background description of the oceanography along each of these sections. Simulations of Argo floats in the Southern Ocean State Estimate (SOSE) and data-assimilating HYCOM model and previous Argo trajectories are used to predict ensemble float trajectories. Trajectories and water mass regimes from floats after deployment have generally agreed well with those projected prior to deployment. The exercise of examining this suite of information prior to the deployment cruises provides valuable regional information for interpreting the actual SOCCOM float profiles and trajectories. Particularly useful are demarcation of the major frontal regimes and their relation to sea ice and topography, regions of upwelling from the deep ocean to the surface, and upper ocean mode water regions associated with both the Subantarctic and Polar Fronts.

Exceptional vertebrate biotas from the Triassic of China, and the expansion of marine ecosystems after the Permo-Triassic mass extinction

NASA Astrophysics Data System (ADS)

Benton, Michael J.; Zhang, Qiyue; Hu, Shixue; Chen, Zhong-Qiang; Wen, Wen; Liu, Jun; Huang, Jinyuan; Zhou, Changyong; Xie, Tao; Tong, Jinnan; Choo, Brian

2013-10-01

The Triassic was a time of turmoil, as life recovered from the most devastating of all mass extinctions, the Permo-Triassic event 252 million years ago. The Triassic marine rock succession of southwest China provides unique documentation of the recovery of marine life through a series of well dated, exceptionally preserved fossil assemblages in the Daye, Guanling, Zhuganpo, and Xiaowa formations. New work shows the richness of the faunas of fishes and reptiles, and that recovery of vertebrate faunas was delayed by harsh environmental conditions and then occurred rapidly in the Anisian. The key faunas of fishes and reptiles come from a limited area in eastern Yunnan and western Guizhou provinces, and these may be dated relative to shared stratigraphic units, and their palaeoenvironments reconstructed. The Luoping and Panxian biotas, both from the Guanling Formation, are dated as Anisian (Pelsonian) on the basis of conodonts and radiometric dates, the former being slightly older than the latter. The Xingyi biota is from the Zhuganpo Formation, and is Ladinian or early Carnian, while the Guanling biota is from the overlying Xiaowa Formation, dated as Carnian. The first three biotas include extensive benthos and burrowing in the sediments, and they were located in restricted basins close to shore. Further, even though the Luoping and Panxian biotas are of similar age, their faunas differ significantly, reflecting perhaps palaeogeographically isolated basins. Between the time of the Xingyi and Guanling biotas, there was a major transgression, and the Guanling biota is entirely different in character from the other three, being dominated by pelagic forms such as large floating crinoids attached to logs, very large ichthyosaurs and thalattosaurs, and pseudoplanktonic bivalves, with no benthos and no burrowing. Phylogenetic study of the fishes and marine reptiles shows apparently explosive diversification among 20 actinopterygian lineages very early in the Early Triassic, but a later expansion of marine reptile groups, in the late Olenekian and early Anisian. This offset in diversification patterns is matched by comparisons of feeding guild categories and body size data. New research tools will shed considerable light on the phylogenetic and ecological implications of recovery of mairne vertebrates in the Triassic.

The European Marine Observing Network and the development of an Integrated European Ocean Observing System. An EuroGOOS perspective

NASA Astrophysics Data System (ADS)

Fernandez, Vicente; Gorringe, Patrick; Nolan, Glenn

2016-04-01

The ocean benefits many sectors of society, being the biggest reservoir of heat, water, carbon and oxygen and playing a fundamental role regulating the earth's climate. We rely on the oceans for food, transport, energy and recreation. Therefore, a sustained marine observation network is crucial to further our understanding of the oceanic environment and to supply scientific data to meet society's need. Marine data and observations in Europe, collected primarily by state governmental agencies, is offered via five Regional Operational Oceanographic Systems (ROOS) within the context of EuroGOOS (http://www.eurogos.eu), an International Non-Profit Association of national governmental agencies and research organizations (40 members from 19 member states) committed to European-scale operational oceanography within the context of the Intergovernmental Global Ocean Observing System (GOOS). Strong cooperation within these regions, enabling the involvement of additional partners and countries, forms the basis of EuroGOOS work. Ocean data collected from different type of sensors (e.g. moored buoys, tide gauges, Ferrybox systems, High Frequency radars, gliders and profiling floats) is accessible to scientist and other end users through data portals and initiatives such as the European Marine Observations and Data Network (EMODnet) (www.emodnet.eu) and the Copernicus Marine Service Copernicus (www.copernicus.eu). Although a relatively mature European ocean observing capability already exists and its well-coordinated at European level, some gaps have been identified, for example the demand for ecosystem products and services, or the case that biogeochemical observations are still relatively sparse particularly in coastal and shelf seas. Assessing gaps based on the capacity of the observing system to answer key societal challenges e.g. site suitability for aquaculture and ocean energy, oil spill response and contextual oceanographic products for fisheries and ecosystems is still required. In this respect, an important effort is being carried out at European level aiming to stablish and consolidate an Integrated and sustained European Ocean Observing System (EOOS). In this paper we present the emerging vision for EOOS with a review of the existing observing networks on which it will be based.

Interactions of marine mammals and birds with offshore membrane enclosures for growing algae (OMEGA).

PubMed

Hughes, Stephanie N; Tozzi, Sasha; Harris, Linden; Harmsen, Shawn; Young, Colleen; Rask, Jon; Toy-Choutka, Sharon; Clark, Kit; Cruickshank, Marilyn; Fennie, Hamilton; Kuo, Julie; Trent, Jonathan D

2014-01-01

OMEGA is an integrated aquatic system to produce biofuels, treat and recycle wastewater, capture CO2, and expand aquaculture production. This system includes floating photobioreactors (PBRs) that will cover hundreds of hectares in marine bays. To assess the interactions of marine mammals and birds with PBRs, 9 × 1.3 m flat panel and 9.5 × 0.2 m tubular PBRs were deployed in a harbor and monitored day and night from October 10, 2011 to Janurary 22, 2012 using infrared video. To observe interactions with pinnipeds, two trained sea lions (Zalophus californianus) and one trained harbor seal (Phoca vitulina richardii) were observed and directed to interact with PBRs in tanks. To determine the forces required to puncture PBR plastic and the effects of weathering, Instron measurements were made with a sea otter (Enhydra lutris) tooth and bird beaks. A total of 1,445 interactions of marine mammals and birds with PBRs were observed in the 2,424 hours of video recorded. The 95 marine mammal interactions, 94 by sea otters and one by a sea lion had average durations of three minutes (max 44 min) and represented about 1% of total recording time. The 1,350 bird interactions, primarily coots (Fulica americana) and gulls (Larus occidentalis and L. californicus) had average durations of six minutes (max. 170) and represented 5% of recording time. Interactive behaviors were characterized as passive (feeding, walking, resting, grooming, and social activity) or proactive (biting, pecking, investigating, and unspecified manipulating). Mammal interactions were predominantly proactive, whereas birds were passive. All interactions occurred primarily during the day. Ninety-six percent of otter interactions occurred in winter, whereas 73% of bird interactions in fall, correlating to their abundance in the harbor. Trained pinnipeds followed most commands to bite, drag, and haul-out onto PBRs, made no overt undirected interactions with the PBRs, but showed avoidance behavior to PBR tethers. Instron measurements indicated that sea-otter teeth and gull beaks can penetrate weathered plastic more easily than new plastic. Otter and bird interactions with experimental PBRs were benign. Large-scale OMEGA systems are predicted to have both positive and negative environmental consequences.

GTSnext: towards a next generation of the geological time scale over the last 100 millions years. (Invited)

NASA Astrophysics Data System (ADS)

Kuiper, K.; Condon, D.; Hilgen, F.; Laskar, J.; Mezger, K.; Pälike, H.; Quidelleur, X.; Schaltegger, U.; Sprovieri, M.; Storey, M.; Wijbrans, J. R.

2009-12-01

The principal scientific objective of the Marie Curie Initial Trainings Network GTSnext is to establish the next generation standard Geological Time Scale with unprecedented accuracy, precision and resolution through integration and intercalibration of state-of-the-art numerical dating techniques. Such time scales underlie all fields in the Earth Sciences and their application will significantly contribute to a much enhanced understanding of Earth System evolution. During the last decade deep marine successions were successfully employed to establish an astronomical tuning for the entire Neogene, as incorporated in the standard Geological Time Scale (ATNTS2004). In GTSnext we aim to fine-tune this Neogene time scale, before it can reliably be used to accurately determine phase relations between astronomical forcing and climate response in the Neogene and possibly also the Oligocene. Radio-isotopic dating of late Neogene ash layers offers excellent opportunities for gaining insight into isotope systematics via their independent dating by astronomical tuning. An example of this synergy is the development of astronomically calibrated standards for 40Ar/39Ar geochronology. The cross-calibration between the different methods might also yield information on the fundamental problem of potential residence times in U/Pb dating. Extension of the astronomical time scale into the Paleogene seems limited to ~40 Ma due to the accuracy of the current astronomical solution. However, the 405 kyr eccentricity component is very stable permitting its use in time scale calibrations back to 250 Ma using only this frequency. This cycle is strong and well developed in Oligocene and even Eocene records. Phase relations between cyclic paleo-climate records and the 405 kyr eccentricity cycle are typically straightforward and unambiguous. Therefore, a first-order tuning to ~405 kyr eccentricity can only be revised by shifting the tuning with (multiples of) ~405 kyr. Isotopic age constraints of both U/Pb and 40Ar/39Ar will be used to anchor floating astronomical tunings, but absolute uncertainties in isotopic ages should be less than ± 200 kyr. The Cretaceous is famous for its remarkable cyclic successions of marine pelagic sediments which bear the unmistakable imprint of astronomical climate forcing. As a consequence floating astrochronologies which are based on number of cycles have been developed for significant portions of the Cretaceous, covering a number of geological stages. Unfortunately, such floating time scales provide us only with the duration of stages but not with their age. However, due to significant improvements in numerical astronomical solutions for the Solar System and in the accuracy of radio-isotopic dating we will try to establish a tuned time scale for the Late Cretaceous. Classical cyclic sections in Europe (e.g. Sopelana, Spain) will be used for the tuning, but lack ash beds. Therefore, radio-isotopic age constraints necessary for the tuning will come from ash beds in the Western Interior Basin in North America. Here we will present the first results of the GTSnext project.

Floating gastroretentive drug delivery systems: Comparison of experimental and simulated dissolution profiles and floatation behavior.

PubMed

Eberle, Veronika A; Schoelkopf, Joachim; Gane, Patrick A C; Alles, Rainer; Huwyler, Jörg; Puchkov, Maxim

2014-07-16

Gastroretentive drug delivery systems (GRDDS) play an important role in the delivery of drug substances to the upper part of the gastrointestinal tract; they offer a possibility to overcome the limited gastric residence time of conventional dosage forms. The aim of the study was to understand drug-release and floatation mechanisms of a floating GRDDS based on functionalized calcium carbonate (FCC). The inherently low apparent density of the excipient (approx. 0.6 g/cm(3)) enabled a mechanism of floatation. The higher specific surface of FCC (approx. 70 m(2)) allowed sufficient hardness of resulting compacts. The floating mechanism of GRDDS was simulated in silico under simulated acidic and neutral conditions, and the results were compared to those obtained in vitro. United States Pharmacopeia (USP) dissolution methods are of limited usefulness for evaluating floating behavior and drug release of floating dosage forms. Therefore, we developed a custom-built stomach model to simultaneously analyze floating characteristics and drug release. In silico dissolution and floatation profiles of the FCC-based tablet were simulated using a three-dimensional cellular automata-based model. In simulated gastric fluid, the FCC-based tablets showed instant floatation. The compacts stayed afloat during the measurement in 0.1 N HCl and eroded completely while releasing the model drug substance. When water was used as dissolution medium, the tablets had no floating lag time and sank down during the measurement, resulting in a change of release kinetics. Floating dosage forms based on FCC appear promising. It was possible to manufacture floating tablets featuring a density of less than unity and sufficient hardness for further processing. In silico dissolution simulation offered a possibility to understand floating behavior and drug-release mechanism. Copyright © 2014 Elsevier B.V. All rights reserved.

50 CFR 86.13 - What is boating infrastructure?

Code of Federal Regulations, 2010 CFR

2010-10-01

..., currents, etc., that provide a temporary safe anchorage point or harbor of refuge during storms); (f) Floating docks and fixed piers; (g) Floating and fixed breakwaters; (h) Dinghy docks (floating or fixed...

Effects of floating gate structures on the two-dimensional electron gas density and electron mobility in AlGaN/AlN/GaN heterostructure field-effect transistors

NASA Astrophysics Data System (ADS)

Zhao, Jingtao; Zhao, Zhenguo; Chen, Zidong; Lin, Zhaojun; Xu, Fukai

2017-12-01

In this study, we have investigated the electrical properties of the AlGaN/AlN/GaN heterostructure field-effect transistors (HFETs) with floating gate structures using the measured capacitancevoltage (C-V) and current-voltage (I-V) characteristics. It is found that the two-dimensional electron gas (2DEG) density under the central gate cannot be changed by the floating gate structures. However, the floating gate structures can cause the strain variation in the barrier layer, which lead to the non-uniform distribution of the polarization charges, then induce a polarization Coulomb field and scatter the 2DEG. More floating gate structures and closer distance between the floating gates and the central gate will result in stronger scattering effect of the 2DEG.

A novel grounded to floating admittance converter with electronic control

NASA Astrophysics Data System (ADS)

Prasad, Dinesh; Ahmad, Javed; Srivastava, Mayank

2018-01-01

This article suggests a new grounded to floating admittance convertor employing only two voltage differencing transconductance amplifiers (VDTAs). The proposed circuit can convert any arbitrary grounded admittance into floating admittance with electronically controllable scaling factor. The presented converter enjoys the following beneficial: (1) no requirement of any additional passive element (2) scaling factor can be tuned electronically through bias currents of VDTAs (3) no matching constraint required (4) low values of active/passive sensitivity indexes and (5) excellent non ideal behavior that indicates no deviation in circuit behavior even under non ideal environment. Application of the proposed configuration in realization of floating resistor and floating capacitor has been presented and the workability of these floating elements has been confirmed by active filter design examples. SPICE simulations have been performed to demonstrate the performance of the proposed circuits.

Extraction of the gate capacitance coupling coefficient in floating gate non-volatile memories: Statistical study of the effect of mismatching between floating gate memory and reference transistor in dummy cell extraction methods

NASA Astrophysics Data System (ADS)

Rafhay, Quentin; Beug, M. Florian; Duane, Russell

2007-04-01

This paper presents an experimental comparison of dummy cell extraction methods of the gate capacitance coupling coefficient for floating gate non-volatile memory structures from different geometries and technologies. These results show the significant influence of mismatching floating gate devices and reference transistors on the extraction of the gate capacitance coupling coefficient. In addition, it demonstrates the accuracy of the new bulk bias dummy cell extraction method and the importance of the β function, introduced recently in [Duane R, Beug F, Mathewson A. Novel capacitance coupling coefficient measurement methodology for floating gate non-volatile memory devices. IEEE Electr Dev Lett 2005;26(7):507-9], to determine matching pairs of floating gate memory and reference transistor.

NPSNET: Dynamic Terrain and Cultured Feature Depiction

DTIC Science & Technology

1992-09-01

defaults. bridge(terrain *ptr, vertex pos, bridge mattype bmat ); This constructor takes only the pointer to the underlying terrain, a placement, and a...material to use for construction. bridge(terrain *ptr, vertex pos, bridge-mattype bmat , float dir); This constructor takes a terrain pointer, a...placement position, a material to use, and a direction to run. bridge(terrain *ptr, vertex pos, bridge-mattype bmat , float dir, float width, float height

Observations of Transient ISS Floating Potential Variations During High Voltage Solar Array Operations

NASA Technical Reports Server (NTRS)

Willis, Emily M.; Minow, Joseph I.; Parker, Linda N.; Pour, Maria Z. A.; Swenson, Charles; Nishikawa, Ken-ichi; Krause, Linda Habash

2016-01-01

The International Space Station (ISS) continues to be a world-class space research laboratory after over 15 years of operations, and it has proven to be a fantastic resource for observing spacecraft floating potential variations related to high voltage solar array operations in Low Earth Orbit (LEO). Measurements of the ionospheric electron density and temperature along the ISS orbit and variations in the ISS floating potential are obtained from the Floating Potential Measurement Unit (FPMU). In particular, rapid variations in ISS floating potential during solar array operations on time scales of tens of milliseconds can be recorded due to the 128 Hz sample rate of the Floating Potential Probe (FPP) pro- viding interesting insight into high voltage solar array interaction with the space plasma environment. Comparing the FPMU data with the ISS operations timeline and solar array data provides a means for correlating some of the more complex and interesting transient floating potential variations with mission operations. These complex variations are not reproduced by current models and require further study to understand the underlying physical processes. In this paper we present some of the floating potential transients observed over the past few years along with the relevant space environment parameters and solar array operations data.

Controlled release floating multiparticulates of metoprolol succinate by hot melt extrusion.

PubMed

Malode, Vilas N; Paradkar, Anant; Devarajan, Padma V

2015-08-01

We present hot melt extrusion (HME) for the design of floating multiparticulates. Metoprolol succinate was selected as the model drug. Our foremost objective was to optimize the components Eudragit(®) RS PO, polyethylene oxide (PEO) and hydroxypropyl methylcellulose (HPMC) to balance both buoyancy and controlled release. Gas generated by sodium bicarbonate in acidic medium was trapped in the polymer matrix to enable floating. Eudragit(®) RS PO and PEO with sodium bicarbonate resulted in multiparticulates which exhibited rapid flotation within 3 min but inadequate total floating time (TFT) of 3h. Addition of HPMC to the matrix did not affect floating lag time (FLT), moreover TFT increased to more than 12h with controlled release of metoprolol succinate. Floating multiparticulates exhibited t50% of 5.24h and t90% of 10.12h. XRD and DSC analysis revealed crystalline state of drug while FTIR suggested nonexistence of chemical interaction between the drug and the other excipients. The assay, FLT, TFT and the drug release of the multiparticulates were unchanged when stored at 40°C/75%RH for 3 months confirming stability. We present floating multiparticulates by HME which could be extrapolated to a range of other drugs. Our approach hence presents platform technology for floating multiparticulates. Copyright © 2015 Elsevier B.V. All rights reserved.

Impact of associated injuries in the Floating knee: A retrospective study

PubMed Central

Rethnam, Ulfin; Yesupalan, Rajam S; Nair, Rajagopalan

2009-01-01

Background Floating knee injuries are usually associated with other significant injuries. Do these injuries have implications on the management of the floating knee and the final outcome of patients? Our study aims to assess the implications of associated injuries in the management and final outcome of floating knee. Methods 29 patients with floating knees were assessed in our institution. A retrospective analysis of medical records and radiographs were done and all associated injuries were identified. The impact of associated injuries on delay in initial surgical management, delay in rehabilitation & final outcome of the floating knee were assessed. Results 38 associated injuries were noted. 7 were associated with ipsilateral knee injuries. Lower limb injuries were most commonly associated with the floating knee. Patients with some associated injuries had a delay in surgical management and others a delay in post-operative rehabilitation. Knee ligament and vascular injuries were associated with poor outcome. Conclusion The associated injuries were quite frequent with the floating knee. Some of the associated injuries caused a delay in surgical management and post-operative rehabilitation. In assessment of the final outcome, patients with associated knee and vascular injuries had a poor prognosis. Majority of the patients with associated injuries had a good or excellent outcome. PMID:19144197

The R/V Folger a Floating Laboratory: Teaching Marine Science Skills on Lake Champlain (Invited)

NASA Astrophysics Data System (ADS)

Manley, P.; Manley, T.

2013-12-01

Undergraduate senior work has been required at Middlebury College as far back as 1960's and hands-on experiential learning was and still is the mode for our geology courses. The history of Middlebury College having a research vessel started in the 1970's when Dave Folger started the marine component of our curriculum and obtained the first Middlebury College's research vessel - a coast guard rescue surf boat (Bruno Schmidt). The second Middlebury College research vessel, the R/V Baldwin was purchased in 1985 and was used exclusively in a river-like setting due to its open cockpit and minimal research equipment. In 1990, Middlebury College received a grant from NSF-MRI to upgrade the vessel, to a then state-of the-art small oceanographic vessel including new equipment (CTD, side-scan sonar, ROV, met station, coring devices, computers and navigation). Middlebury College contributed monies to enclose the wheelhouse, install safer diesel engines, as well as a winch and an A-frame to haul in equipment. Over 600+ students used the Baldwin in a variety of geology courses; mainly Oceanography and Marine Geology. In 2010, Middlebury College received an NSF -ARRA grant (American Recovery and Reinvestment Act) to replace the ailing R/V Baldwin with a floating state-of-the art laboratory with the specific goals of increasing 1) access to lake research for Middlebury faculty and students in the biological, chemical, and environmental sciences, 2) the scope of lake research by reducing transit times over this 100km long lake, 3) stability for broad-lake research, 4) improve and expand research capabilities on Lake Champlain, 5) the carrying capacity (both equipment and people), and 6) instructional capability and overnight capabilities. The newly built R/V Folger is a sophisticated research vessel with advanced capabilities that provides a greater capacity to the research infrastructure on Lake Champlain, enhancing interdisciplinary inquiry not only for Middlebury College, but for other members of the local educational community for the next 30 to 50 years. The R/V Folger hosts significant amount of lab space allowing for on-vessel processing of real time data, enhanced navigational capabilities, smart classroom technology and new instrumentation such as multi-beam and CTD-rosette system. This all aluminum new research vessel, besides providing a new platform for Middlebury College's students, will also be used to enable faculty at other local colleges to provide experiential training in research techniques that would otherwise be unavailable; provide research training to local K-12 teachers; offer outreach to "land-locked" institutions and organizations within our tri-state region (NY, NH and VT); the development of a nautical archaeology program in the Lake Champlain basin; and produce data with environmental benefits to the region.

Paranoia.Ada: A diagnostic program to evaluate Ada floating-point arithmetic

NASA Technical Reports Server (NTRS)

Hjermstad, Chris

1986-01-01

Many essential software functions in the mission critical computer resource application domain depend on floating point arithmetic. Numerically intensive functions associated with the Space Station project, such as emphemeris generation or the implementation of Kalman filters, are likely to employ the floating point facilities of Ada. Paranoia.Ada appears to be a valuabe program to insure that Ada environments and their underlying hardware exhibit the precision and correctness required to satisfy mission computational requirements. As a diagnostic tool, Paranoia.Ada reveals many essential characteristics of an Ada floating point implementation. Equipped with such knowledge, programmers need not tremble before the complex task of floating point computation.

Floating point only SIMD instruction set architecture including compare, select, Boolean, and alignment operations

DOEpatents

Gschwind, Michael K [Chappaqua, NY

2011-03-01

Mechanisms for implementing a floating point only single instruction multiple data instruction set architecture are provided. A processor is provided that comprises an issue unit, an execution unit coupled to the issue unit, and a vector register file coupled to the execution unit. The execution unit has logic that implements a floating point (FP) only single instruction multiple data (SIMD) instruction set architecture (ISA). The floating point vector registers of the vector register file store both scalar and floating point values as vectors having a plurality of vector elements. The processor may be part of a data processing system.

The Floating Upper Limb: Multiple Injuries Involving Ipsilateral, Proximal, Humeral, Supracondylar, and Distal Radial Limb

PubMed Central

Manaan, Qazi; Bashir, Adil; Zahoor, Adnan; Mokhdomi, Taseem A.

2016-01-01

Floating arm injury represents a common yet complicated injury of the childhood severely associated with limb deformation and even morbidity, if not precisely addressed and credibly operated. Here, we report a rare floating upper limb case of a 9-year-old boy with multiple injuries of ipsilateral proximal humeral, supracondylar and distal radial limb. This is the first report to document such a combined floating elbow and floating arm injury in the same limb. In this report, we discuss the surgical procedures used and recovery of the patient monitored to ascertain the effectiveness of the method in limb reorganisation. PMID:27583121

The Floating Upper Limb: Multiple Injuries Involving Ipsilateral, Proximal, Humeral, Supracondylar, and Distal Radial Limb.

PubMed

Manaan, Qazi; Bashir, Adil; Zahoor, Adnan; Mokhdomi, Taseem A; Danish, Qazi

2016-09-01

Floating arm injury represents a common yet complicated injury of the childhood severely associated with limb deformation and even morbidity, if not precisely addressed and credibly operated. Here, we report a rare floating upper limb case of a 9-year-old boy with multiple injuries of ipsilateral proximal humeral, supracondylar and distal radial limb. This is the first report to document such a combined floating elbow and floating arm injury in the same limb. In this report, we discuss the surgical procedures used and recovery of the patient monitored to ascertain the effectiveness of the method in limb reorganisation.

[Treatment of Persistent Somatoform Pain Disorder by Floating Needle Therapy and Duloxetine].

PubMed

Ren, Wan-wen; Zhou, Zhi-ying; Xu, Mi-mi; Long, Sen; Tang, Guang-zheng; Mao, Hong-jing; Chen, Shu-lin

2016-02-01

To evaluate clinical effect and safety of floating needle therapy and duloxetine in treating patients with persistent somatoform pain disorder (PSPD). Totally 108 PSPD patients were randomly assigned to the floating needle treatment group, the duloxetine treatment group, and the placebo treatment group, 36 in each group. Patients in the floating needle treatment group received floating needle therapy and placebo. Those in the duloxetine treatment group received duloxetine and simulated floating needle therapy. Those in the placebo treatment group received the placebo and simulated floating needle therapy. All treatment lasted for six weeks. Efficacy and adverse reactions were evaluated using Simple McGill pain scale (SF-MPQ) and Treatment Emergent Symptom Scale (TESS) before treatment and immediately after treatment, as well as at the end of 1st, 2nd, 4th, and 6th week of treatment, respectively. Hamilton Depression Scale (HAMD, 17 items), Hamilton Anxiety Scale (HAMA) were assessed before treatment and at the end of 1st, 2nd, 4th, and 6th week of treatment, respectively. Patients in the floating needle treatment group and the duloxetine treatment group with the total reducing score rate of SF-MPQ in Pain Rating index (PRI) ≥ 50% after 6 weeks' treatment were involved in the follow-up study. (1) Compared with the same group before treatment, SF-MPQ score, HAMD score and HAMA total scores all decreased in all the three groups at the end of 1st, 2nd, 4th, and 6th week of treatment (P < 0.05, P < 0.01). Besides , each item of SF-MPQ significantly decreased immediately after treatment in the floating needle treatment group (P < 0.01). Compared with the placebo treatment group, SF-MPQ, HAMD, and HAMA total score in the floating needle treatment group significantly decreased after 1, 2, 4, and 6 weeks of treatment (P < 0.05, P < 0.01). SF-MPQ score, HAMD score and HAMA total score in the duloxetine treatment group also significantly decreased after 2, 4, and 6 weeks of treatment (P < 0.05, P < 0.01). (2) There were 3 patients (8.3%) who had adverse reactions in the floating needle treatment group, 17 (50.0%) in the duloxetine treatment group, and 7 (21.2%) in the placebo treatment group. Compared with the placebo treatment group, the incidence of adverse reaction increased in the duloxetine treatment group (χ² = 6.04, P < 0.05). Besides, it was higher in the duloxetine treatment group than in the floating needle treatment group (χ² = 14.9, P < 0.05). (3) There were 19 patients in the floating needle treatment group and 17 patients in the duloxetine treatment group involved in the follow-up study. Compared with 6 weeks after treatment, no significant difference was observed at 3 and 6 months after treatment in the score of SF-MPQ, HAMD, and HAMA in the floating needle treatment group and the duloxetine treatment group. No significant difference was observed between the two groups (P > 0.05). There were 5 patients (29.4%) who had adverse reactions in the duloxetine treatment group, and no adverse reactions were observed in the floating needle treatment group. The adverse reaction rate was significantly different between the two groups (χ² = 4.26, P < 0.05). Floating needle therapy and duloxetine were effective in treatment of patients with PSPD. However, floating needle therapy could relieve pain more rapidly than duloxetine, with obviously less adverse reactions.

Improvements in floating point addition/subtraction operations

DOEpatents

Farmwald, P.M.

1984-02-24

Apparatus is described for decreasing the latency time associated with floating point addition and subtraction in a computer, using a novel bifurcated, pre-normalization/post-normalization approach that distinguishes between differences of floating point exponents.

Differences in evaporation between a floating pan and class a pan on land

USGS Publications Warehouse

Masoner, J.R.; Stannard, D.I.; Christenson, S.C.

2008-01-01

Research was conducted to develop a method for obtaining floating pan evaporation rates in a small (less than 10,000 m2) wetland, lagoon, or pond. Floating pan and land pan evaporation data were collected from March 1 to August 31, 2005, at a small natural wetland located in the alluvium of the Canadian River near Norman, Oklahoma, at the U.S. Geological Survey Norman Landfill Toxic Substances Hydrology Research Site. Floating pan evaporation rates were compared with evaporation rates from a nearby standard Class A evaporation pan on land. Floating pan evaporation rates were significantly less than land pan evaporation rates for the entire period and on a monthly basis. Results indicated that the use of a floating evaporation pan in a small free-water surface better simulates actual physical conditions on the water surface that control evaporation. Floating pan to land pan ratios were 0.82 for March, 0.87 for April, 0.85 for May, 0.85 for June, 0.79 for July, and 0.69 for August. ?? 2008 American Water Resources Association.

Measuring the Coefficient of Friction of a Small Floating Liquid Marble

PubMed Central

Ooi, Chin Hong; Nguyen, Anh Van; Evans, Geoffrey M.; Dao, Dzung Viet; Nguyen, Nam-Trung

2016-01-01

This paper investigates the friction coefficient of a moving liquid marble, a small liquid droplet coated with hydrophobic powder and floating on another liquid surface. A floating marble can easily move across water surface due to the low friction, allowing for the transport of aqueous solutions with minimal energy input. However, the motion of a floating marble has yet to be systematically characterised due to the lack of insight into key parameters such as the coefficient of friction between the floating marble and the carrier liquid. We measured the coefficient of friction of a small floating marble using a novel experimental setup that exploits the non-wetting properties of a liquid marble. A floating liquid marble pair containing a minute amount magnetite particles were immobilised and then released in a controlled manner using permanent magnets. The capillarity-driven motion was analysed to determine the coefficient of friction of the liquid marbles. The “capillary charge” model was used to fit the experimental results. We varied the marble content and carrier liquid to establish a relationship between the friction correction factor and the meniscus angle. PMID:27910916

Enhancement of Biomass and Lipid Productivities of Water Surface-Floating Microalgae by Chemical Mutagenesis

PubMed Central

Nojima, Daisuke; Ishizuka, Yuki; Muto, Masaki; Ujiro, Asuka; Kodama, Fumito; Yoshino, Tomoko; Maeda, Yoshiaki; Matsunaga, Tadashi; Tanaka, Tsuyoshi

2017-01-01

Water surface-floating microalgae have great potential for biofuel applications due to the ease of the harvesting process, which is one of the most problematic steps in conventional microalgal biofuel production. We have collected promising water surface-floating microalgae and characterized their capacity for biomass and lipid production. In this study, we performed chemical mutagenesis of two water surface-floating microalgae to elevate productivity. Floating microalgal strains AVFF007 and FFG039 (tentatively identified as Botryosphaerella sp. and Chlorococcum sp., respectively) were exposed to ethyl methane sulfonate (EMS) or 1-methyl-3-nitro-1-nitrosoguanidine (MNNG), and pale green mutants (PMs) were obtained. The most promising FFG039 PM formed robust biofilms on the surface of the culture medium, similar to those formed by wild type strains, and it exhibited 1.7-fold and 1.9-fold higher biomass and lipid productivities than those of the wild type. This study indicates that the chemical mutation strategy improves the lipid productivity of water surface-floating microalgae without inhibiting biofilm formation and floating ability. PMID:28555001

Enhancement of Biomass and Lipid Productivities of Water Surface-Floating Microalgae by Chemical Mutagenesis.

PubMed

Nojima, Daisuke; Ishizuka, Yuki; Muto, Masaki; Ujiro, Asuka; Kodama, Fumito; Yoshino, Tomoko; Maeda, Yoshiaki; Matsunaga, Tadashi; Tanaka, Tsuyoshi

2017-05-27

Water surface-floating microalgae have great potential for biofuel applications due to the ease of the harvesting process, which is one of the most problematic steps in conventional microalgal biofuel production. We have collected promising water surface-floating microalgae and characterized their capacity for biomass and lipid production. In this study, we performed chemical mutagenesis of two water surface-floating microalgae to elevate productivity. Floating microalgal strains AVFF007 and FFG039 (tentatively identified as Botryosphaerella sp. and Chlorococcum sp., respectively) were exposed to ethyl methane sulfonate (EMS) or 1-methyl-3-nitro-1-nitrosoguanidine (MNNG), and pale green mutants (PMs) were obtained. The most promising FFG039 PM formed robust biofilms on the surface of the culture medium, similar to those formed by wild type strains, and it exhibited 1.7-fold and 1.9-fold higher biomass and lipid productivities than those of the wild type. This study indicates that the chemical mutation strategy improves the lipid productivity of water surface-floating microalgae without inhibiting biofilm formation and floating ability.

Post-LGM grounding line and calving front translations of the West Antarctic Ice Sheet in the Whales Deep paleo-ice-stream trough, eastern Ross Sea, Antarctica

NASA Astrophysics Data System (ADS)

McGlannan, A. J.; Bart, P. J.; Chow, J.

2016-12-01

A large-area (2500 km2) multibeam survey of the Whales Deep paleo-ice-stream trough, eastern Ross Sea, Antarctica was acquired during NBP1502B. This sector of the continental shelf is important as it was covered by grounded and floating ice, which drained the central part of an expanded West Antarctic Ice Sheet (WAIS) during the last glacial cycle. The seafloor geomorphology shows a well-defined cluster of four back stepping grounding zone wedges (GZWs) that were deposited in a partly overlapping fashion on the middle continental shelf during WAIS retreat. These observations permit two end-member possibilities for how the WAIS grounding line and calving front vacated the trough. In the first scenario, each GZW represents successive landward shifts of the grounding line and calving front. In the second scenario, each GZW represents a large-scale retreat and re-advance of grounded and floating ice. To determine which of these two end-member scenarios most accurately describes WAIS retreat from this sector of Ross Sea, we evaluated a grid of kasten and piston cores. The core stations were selected on the basis of backstepping GZWs along the trough axis. Our core data analyses included an integration of visual core descriptions, x-ray images, grain size, water content, total organic carbon, shear strengths, and diatom assemblage data. Core data reveal a single transgressive succession from proximal diamict overlain by sub-ice-shelf and/or open-marine sediments. These data strongly support the first scenario, suggesting that an ice shelf remained continuously intact during the time that the grounding line successively moved from the shelf edge to the middle shelf by small-scale landward translations until the end of the fourth grounding event. Sedimentologic and diatom-assemblage data from the inner shelf show that only the last middle shelf grounding event ended with a long-distance retreat of grounded and then floating ice to south of the modern calving front.

Impact of Preferred Eddy Tracks on Transport and Mixing in the Eastern South Pacific

NASA Astrophysics Data System (ADS)

Belmadani, A.; Donoso, D.; Auger, P. A.; Chaigneau, A.

2017-12-01

Mesoscale eddies, which play a fundamental role in the transport of mass, heat, nutrients, and biota across the oceans, have been suggested to propagate preferently along specific tracks. These preferred pathways, also called eddy trains, are near-zonal due to westward drift of individual vortices, and tend to be polarized (ie alternatively dominated by anticyclonic/cyclonic eddies), coinciding with the recently discovered latent striations (quasi-zonal mesoscale jet-like features). While significant effort has been made to understand the dynamics of striations and their interplay with mesoscale eddies, the impact of repeated eddy tracks on physical (temperature, salinity), biogeochemical (oxygen, carbon, nutrients) and other tracers (e.g. chlorophyll, marine debris) has received little attention. Here we report on the results of numerical modeling experiments that simulate the impact of preferred eddy tracks on the transport and mixing of water particles in the Eastern South Pacific off Chile. A 30-year interannual simulation of the oceanic circulation in this region has been performed over 1984-2013 with the ROMS (Regional Oceanic Modeling System) at an eddy-resolving resolution (10 km). Objective tracking of mesoscale coherent vortices is obtained using automated methods, allowing to compute the contribution of eddies to the ocean circulation. Preferred eddy tracks are further isolated from the more random eddies, by comparing the distances between individual tracks and the striated pattern in long-term mean eddy polarity with a least-squares approach. The remaining non-eddying flow may also be decomposed into time-mean and anomalous circulation, and/or small- and large-scale circulation. Neutrally-buoyant Lagrangian floats are then released uniformly into the various flow components as well as the total flow, and tracked forward in time with the ARIANE software. The dispersion patterns of water particles are used to estimate the respective contributions of organized and random eddies, mean flow, large-scale perturbations etc. to mixing properties and transport pathways. Float release into the full flow inside selected vortices is also used to document the impact of eddy trains on the transformation of water masses inferred from changes in temperature/salinity along float trajectories.

Worldwide complete spherical Bouguer and isostatic anomaly maps

NASA Astrophysics Data System (ADS)

Bonvalot, S.; Balmino, G.; Briais, A.; Peyrefitte, A.; Vales, N.; Biancale, R.; Gabalda, G.; Reinquin, F.

2011-12-01

We present here a set of digital maps of the Earth's gravity anomalies (surface "free air", Bouguer and isostatic), computed at Bureau Gravimetric International (BGI) as a contribution to the Global Geodetic Observing Systems (GGOS) and to the global geophysical maps published by the Commission for the Geological Map of the World (CGMW). The free air and Bouguer anomaly concept is extensively used in geophysical interpretation to investigate the density distributions in the Earth's interior. Complete Bouguer anomalies (including terrain effects) are usually computed at regional scales by integrating the gravity attraction of topography elements over and beyond a given area (under planar or spherical approximations). Here, we developed and applied a worldwide spherical approach aimed to provide a set of homogeneous and high resolution gravity anomaly maps and grids computed at the Earth's surface, taking into account a realistic Earth model and reconciling geophysical and geodetic definitions of gravity anomalies. This first version (1.0) has been computed by spherical harmonics analysis / synthesis of the Earth's topography-bathymetry up to degree 10800. The detailed theory of the spherical harmonics approach is given in Balmino et al., (Journal of Geodesy, submitted). The Bouguer and terrain corrections have thus been computed in spherical geometry at 1'x1' resolution using the ETOPO1 topography/bathymetry, ice surface and bedrock models from the NOAA (National Oceanic and Atmospheric Administration) and taking into account precise characteristics (boundaries and densities) of major lakes, inner seas, polar caps and of land areas below sea level. Isostatic corrections have been computed according to the Airy Heiskanen model in spherical geometry for a constant depth of compensation of 30km. The gravity information given here is provided by the Earth Geopotential Model (EGM2008), developed at degree 2160 by the National Geospatial Intelligence Agency (NGA) (Pavlis et al., 2008), which represents the best up-to-date global gravity model (including surface gravity measurements from land, marine and airborne surveys as well as gravity and altimetry satellite measurements). The surface gravity anomaly (free air) is computed at the Earth's surface in the context of Molodensky theory and includes corrections from the mass of the atmosphere. The way gravity anomalies are computed on a worldwide basis slightly differs from the classical usage, but meets modern concerns which tend to take the real Earth into account. The resulting anomaly maps and grids will be distributed for scientific and education purposes by the Commission for the Geological Map of the World (CGMW) with support of UNESCO and other institutions. Upgraded versions might be done as soon as new global gravity model is available (including satellite GOCE and new surface measurements: ground, airborne). Visit / contact BGI (http://bgi.omp.obs-mip.fr) and CCMW (http://ccgm.free.fr) for more information.

14 CFR 25.525 - Application of loads.

Code of Federal Regulations, 2014 CFR

2014-01-01

... not less than those prescribed in § 25.533(b). (c) For twin float seaplanes, each float must be... twin float seaplane. (d) Except in the takeoff condition of § 25.531, the aerodynamic lift on the...

14 CFR 25.525 - Application of loads.

Code of Federal Regulations, 2011 CFR

2011-01-01

... not less than those prescribed in § 25.533(b). (c) For twin float seaplanes, each float must be... twin float seaplane. (d) Except in the takeoff condition of § 25.531, the aerodynamic lift on the...

14 CFR 25.525 - Application of loads.

Code of Federal Regulations, 2010 CFR

2010-01-01

... not less than those prescribed in § 25.533(b). (c) For twin float seaplanes, each float must be... twin float seaplane. (d) Except in the takeoff condition of § 25.531, the aerodynamic lift on the...

14 CFR 25.525 - Application of loads.

Code of Federal Regulations, 2012 CFR

2012-01-01

... not less than those prescribed in § 25.533(b). (c) For twin float seaplanes, each float must be... twin float seaplane. (d) Except in the takeoff condition of § 25.531, the aerodynamic lift on the...

14 CFR 25.525 - Application of loads.

Code of Federal Regulations, 2013 CFR

2013-01-01

... not less than those prescribed in § 25.533(b). (c) For twin float seaplanes, each float must be... twin float seaplane. (d) Except in the takeoff condition of § 25.531, the aerodynamic lift on the...

Bifurcated method and apparatus for floating point addition with decreased latency time

DOEpatents

Farmwald, Paul M.

1987-01-01

Apparatus for decreasing the latency time associated with floating point addition and subtraction in a computer, using a novel bifurcated, pre-normalization/post-normalization approach that distinguishes between differences of floating point exponents.

An Analysis of the Full-Floating Journal Bearing

NASA Technical Reports Server (NTRS)

Shaw, M C; Nussdorfer, T J , Jr

1947-01-01

An analysis of the operating characteristics of a full-floating journal bearing, a bearing in which a floating sleeve is located between the journal and bearing surfaces, is presented together with charts from which the performance of such bearings may be predicted. Examples are presented to illustrate the use of these charts and a limited number of experiments conducted upon a glass full-floating bearing are reported to verify some results of the analysis.

Electrowetting in a water droplet with a movable floating substrate

NASA Astrophysics Data System (ADS)

Shahzad, Amir; Masud, A. R.; Song, Jang-Kun

2016-05-01

Electrowetting (EW) enables facile manipulation of a liquid droplet on a hydrophobic surface. In this study, manipulation of an electrolyte droplet having a small floating object on it was investigated on a solid hydrophobic substrate under the EW process. Herein, the floating object exhibited a vertical motion under an applied electric field owing to the spreading and contraction of the droplet on its connecting substrates. The field-induced height variation of the floating object was significantly influenced by the thicknesses of the dielectric and hydrophobic materials. A small mass was also placed on the top floating object and its effect on the spreading of the droplet was observed. In this system, the height of the top floating object is precisely controllable under the application of an electric voltage. The proposed system is expected to be highly useful in the design of nano- and micro-oscillatory systems for microengineering.

Electrowetting in a water droplet with a movable floating substrate.

PubMed

Shahzad, Amir; Masud, A R; Song, Jang-Kun

2016-05-01

Electrowetting (EW) enables facile manipulation of a liquid droplet on a hydrophobic surface. In this study, manipulation of an electrolyte droplet having a small floating object on it was investigated on a solid hydrophobic substrate under the EW process. Herein, the floating object exhibited a vertical motion under an applied electric field owing to the spreading and contraction of the droplet on its connecting substrates. The field-induced height variation of the floating object was significantly influenced by the thicknesses of the dielectric and hydrophobic materials. A small mass was also placed on the top floating object and its effect on the spreading of the droplet was observed. In this system, the height of the top floating object is precisely controllable under the application of an electric voltage. The proposed system is expected to be highly useful in the design of nano- and micro-oscillatory systems for microengineering.

Floating plant dominance as a stable state

PubMed Central

Scheffer, Marten; Szabó, Sándor; Gragnani, Alessandra; van Nes, Egbert H.; Rinaldi, Sergio; Kautsky, Nils; Norberg, Jon; Roijackers, Rudi M. M.; Franken, Rob J. M.

2003-01-01

Invasion by mats of free-floating plants is among the most important threats to the functioning and biodiversity of freshwater ecosystems ranging from temperate ponds and ditches to tropical lakes. Dark, anoxic conditions under thick floating-plant cover leave little opportunity for animal or plant life, and they can have large negative impacts on fisheries and navigation in tropical lakes. Here, we demonstrate that floating-plant dominance can be a self-stabilizing ecosystem state, which may explain its notorious persistence in many situations. Our results, based on experiments, field data, and models, represent evidence for alternative domains of attraction in ecosystems. An implication of our findings is that nutrient enrichment reduces the resilience of freshwater systems against a shift to floating-plant dominance. On the other hand, our results also suggest that a single drastic harvest of floating plants can induce a permanent shift to an alternative state dominated by rooted, submerged growth forms. PMID:12634429

Current-Sensitive Path Planning for an Underactuated Free-Floating Ocean Sensorweb

NASA Technical Reports Server (NTRS)

Dahl, Kristen P.; Thompson, David R.; McLaren, David; Chao, Yi; Chien, Steve

2011-01-01

This work investigates multi-agent path planning in strong, dynamic currents using thousands of highly under-actuated vehicles. We address the specific task of path planning for a global network of ocean-observing floats. These submersibles are typified by the Argo global network consisting of over 3000 sensor platforms. They can control their buoyancy to float at depth for data collection or rise to the surface for satellite communications. Currently, floats drift at a constant depth regardless of the local currents. However, accurate current forecasts have become available which present the possibility of intentionally controlling floats' motion by dynamically commanding them to linger at different depths. This project explores the use of these current predictions to direct float networks to some desired final formation or position. It presents multiple algorithms for such path optimization and demonstrates their advantage over the standard approach of constant-depth drifting.

DIFMOS - A floating-gate electrically erasable nonvolatile semiconductor memory technology. [Dual Injector Floating-gate MOS

NASA Technical Reports Server (NTRS)

Gosney, W. M.

1977-01-01

Electrically alterable read-only memories (EAROM's) or reprogrammable read-only memories (RPROM's) can be fabricated using a single-level metal-gate p-channel MOS technology with all conventional processing steps. Given the acronym DIFMOS for dual-injector floating-gate MOS, this technology utilizes the floating-gate technique for nonvolatile storage of data. Avalanche injection of hot electrons through gate oxide from a special injector diode in each bit is used to charge the floating gates. A second injector structure included in each bit permits discharge of the floating gate by avalanche injection of holes through gate oxide. The overall design of the DIFMOS bit is dictated by the physical considerations required for each of the avalanche injector types. The end result is a circuit technology which can provide fully decoded bit-erasable EAROM-type circuits using conventional manufacturing techniques.

Response diversity of free-floating plants to nutrient stoichiometry and temperature: growth and resting body formation.

PubMed

McCann, Michael J

2016-01-01

Free-floating plants, like most groups of aquatic primary producers, can become nuisance vegetation under certain conditions. On the other hand, there is substantial optimism for the applied uses of free-floating plants, such as wastewater treatment, biofuel production, and aquaculture. Therefore, understanding the species-specific responses of floating plants to abiotic conditions will inform both management decisions and the beneficial applications of these plants. I measured the responses of three floating plant species common in the northeast United States (Lemna minor, Spirodela polyrhiza, and Wolffia brasiliensis) to nutrient stoichiometry (nitrogen and phosphorus) and temperature in the laboratory. I also used survey data to determine the pattern of species richness of floating plants in the field and its relationship with the dominance of this group. Floating plant species exhibited unique responses to nutrient stoichiometry and temperature in the laboratory, especially under low temperatures (18 °C) and low nutrient conditions (0.5 mg N L(-1), 0.083 mg P L(-1)). The three species displayed an apparent tradeoff with different strategies of growth or dormancy. In the field, water bodies with three or more species of floating plants were not more frequently dominated by this group. The response diversity observed in the lab may not be associated with the dominance of this group in the field because it is masked by environmental variability, has a weak effect, or is only important during transient circumstances. Future research to develop applied uses of floating plants should examine response diversity across a greater range of species or clones and environmental conditions.

Response diversity of free-floating plants to nutrient stoichiometry and temperature: growth and resting body formation

PubMed Central

2016-01-01

Free-floating plants, like most groups of aquatic primary producers, can become nuisance vegetation under certain conditions. On the other hand, there is substantial optimism for the applied uses of free-floating plants, such as wastewater treatment, biofuel production, and aquaculture. Therefore, understanding the species-specific responses of floating plants to abiotic conditions will inform both management decisions and the beneficial applications of these plants. I measured the responses of three floating plant species common in the northeast United States (Lemna minor, Spirodela polyrhiza, and Wolffia brasiliensis) to nutrient stoichiometry (nitrogen and phosphorus) and temperature in the laboratory. I also used survey data to determine the pattern of species richness of floating plants in the field and its relationship with the dominance of this group. Floating plant species exhibited unique responses to nutrient stoichiometry and temperature in the laboratory, especially under low temperatures (18 °C) and low nutrient conditions (0.5 mg N L−1, 0.083 mg P L−1). The three species displayed an apparent tradeoff with different strategies of growth or dormancy. In the field, water bodies with three or more species of floating plants were not more frequently dominated by this group. The response diversity observed in the lab may not be associated with the dominance of this group in the field because it is masked by environmental variability, has a weak effect, or is only important during transient circumstances. Future research to develop applied uses of floating plants should examine response diversity across a greater range of species or clones and environmental conditions. PMID:26989619

A Self-Powered Fast-Sampling Profiling Float in support of a Mesoscale Ocean Observing System in the Western North Pacific

NASA Astrophysics Data System (ADS)

Valdez, T.; Chao, Y.; Davis, R. E.; Jones, J.

2012-12-01

This talk will describe a new self-powered profiling float that can perform fast sampling over the upper ocean for long durations in support of a mesoscale ocean observing system in the Western North Pacific. The current state-of-the-art profiling floats can provide several hundreds profiles for the upper ocean every ten days. To quantify the role of the upper ocean in modulating the development of Typhoons requires at least an order of magnitude reduction for the sampling interval. With today's profiling float and battery technology, a fast sampling of one day or even a few hours will reduce the typical lifetime of profiling floats from years to months. Interactions between the ocean and typhoons often involves mesoscale eddies and fronts, which require a dense array of floats to reveal the 3-dimensional structure. To measure the mesoscale ocean over a large area like the Western North Pacific therefore requires a new technology that enables fast sampling and long duration at the same time. Harvesting the ocean renewable energy associated with the vertical temperature differentials has the potential to power profiling floats with fast sampling over long durations. Results from the development and deployment of a prototype self-powered profiling float (known as SOLO-TREC) will be presented. With eight hours sampling in the upper 500 meters, the upper ocean temperature and salinity reveal pronounced high frequency variations. Plans to use the SOLO-TREC technology in support of a dense array of fast sampling profiling floats in the Western North Pacific will be discussed.

Apparatus for removing oil and other floating contaminants from a moving body of water

DOEpatents

Strohecker, J.W.

1973-12-18

The patent describes a process in which floating contaminants such as oil and solid debris are removed from a moving body of water by employing a skimming system which uses the natural gravitational flow of the water. A boom diagonally positioned across the body of water diverts the floating contaminants over a floating weir and into a retention pond where an underflow weir is used to return contaminant-free water to the moving body of water. The floating weir is ballasted to maintain the contaminant-receiving opening therein slightly below the surface of the water during fluctuations in the water level for skimming the contaminants with minimal water removal.

NULL Convention Floating Point Multiplier

PubMed Central

Ramachandran, Seshasayanan

2015-01-01

Floating point multiplication is a critical part in high dynamic range and computational intensive digital signal processing applications which require high precision and low power. This paper presents the design of an IEEE 754 single precision floating point multiplier using asynchronous NULL convention logic paradigm. Rounding has not been implemented to suit high precision applications. The novelty of the research is that it is the first ever NULL convention logic multiplier, designed to perform floating point multiplication. The proposed multiplier offers substantial decrease in power consumption when compared with its synchronous version. Performance attributes of the NULL convention logic floating point multiplier, obtained from Xilinx simulation and Cadence, are compared with its equivalent synchronous implementation. PMID:25879069

NULL convention floating point multiplier.

PubMed

Albert, Anitha Juliette; Ramachandran, Seshasayanan

2015-01-01

Floating point multiplication is a critical part in high dynamic range and computational intensive digital signal processing applications which require high precision and low power. This paper presents the design of an IEEE 754 single precision floating point multiplier using asynchronous NULL convention logic paradigm. Rounding has not been implemented to suit high precision applications. The novelty of the research is that it is the first ever NULL convention logic multiplier, designed to perform floating point multiplication. The proposed multiplier offers substantial decrease in power consumption when compared with its synchronous version. Performance attributes of the NULL convention logic floating point multiplier, obtained from Xilinx simulation and Cadence, are compared with its equivalent synchronous implementation.

Evidence for an ice shelf covering the central Arctic Ocean during the penultimate glaciation

USGS Publications Warehouse

Jakobsson, Martin; Nilsson, Johan; Anderson, Leif G.; Backman, Jan; Bjork, Goran; Cronin, Thomas M.; Kirchner, Nina; Koshurnikov, Andrey; Mayer, Larry; Noormets, Riko; O'Regan, Matthew; Stranne, Christian; Ananiev, Roman; Macho, Natalia Barrientos; Cherniykh, Dennis; Coxall, Helen; Eriksson, Bjorn; Floden, Tom; Gemery, Laura; Gustafsson, Orjan; Jerram, Kevin; Johansson, Carina; Khortov, Alexey; Mohammad, Rezwan; Semiletov, Igor

2016-01-01

The hypothesis of a km-thick ice shelf covering the entire Arctic Ocean during peak glacial conditions was proposed nearly half a century ago. Floating ice shelves preserve few direct traces after their disappearance, making reconstructions difficult. Seafloor imprints of ice shelves should, however, exist where ice grounded along their flow paths. Here we present new evidence of ice-shelf groundings on bathymetric highs in the central Arctic Ocean, resurrecting the concept of an ice shelf extending over the entire central Arctic Ocean during at least one previous ice age. New and previously mapped glacial landforms together reveal flow of a spatially coherent, in some regions >1-km thick, central Arctic Ocean ice shelf dated to marine isotope stage 6 (~140 ka). Bathymetric highs were likely critical in the ice-shelf development by acting as pinning points where stabilizing ice rises formed, thereby providing sufficient back stress to allow ice shelf thickening.

Ocean Color Data at the Goddard DAAC

NASA Technical Reports Server (NTRS)

1999-01-01

The apparent color of the ocean is determined by the interactions of incident light with substances or particles present in the water. The most significant constituents are free-floating photosynthetic organisms (phytoplankton) and inorganic particulates. Phytoplankton contain chlorophyll, which absorbs light at blue and red wavelengths and transmits in the green. Particulate matter can reflect and absorb light, which reduces the clarity (light transmission) of the water. Substances dissolved in water can also affect its color. Observations of ocean color from space, utilizing sensors specially designed to detect the small amount of light radiating from the sea surface, provide a global picture of the patterns of biological productivity in the world's oceans. For that reason, ocean color remote sensing data is a vital resource for biological oceanography. Unlike the limited area of the ocean that can be investigated from a research ship, data from a satellite sensor covers a large region and provides a comprehensive view of the marine environment.

A Surface "Superconvergence" Pathway Connecting the South Indian Ocean to the Subtropical South Pacific Gyre

NASA Astrophysics Data System (ADS)

Maes, C.; Grima, N.; Blanke, B.; Martinez, E.; Paviet-Salomon, T.; Huck, T.

2018-02-01

We study the dispersion and convergence of marine floating material by surface currents from a model reanalysis that represents explicitly mesoscale eddy variability. Lagrangian experiments about the long-term evolution (29 years) of an initially homogeneous concentration of particles are performed at global scale with horizontal current at one fourth degree resolution and refreshed daily over the 1985-2013 period. Results not only confirm and document the five known sites of surface convergence at the scale of individual oceanic basins but also reveal a convergent pathway connecting the South Indian subtropical region with the convergence zone of the South Pacific through the Great Australian Bight, the Tasman Sea, and the southwest Pacific Ocean. This "superconvergent" pathway at the ocean surface is robust and permanent over a distance longer than 8,000 km. The current variability is crucial to sustain this pathway.

Apple Snail: a Bio Cleaner of the Water Free Surface.

NASA Astrophysics Data System (ADS)

Bassiri, Golnaz

2005-11-01

Oil spills from tankers represent a threat for shorelines and marine life. Despite continuing research, there has been little change in the fundamental technology for dealing with oil spills. An experimental investigation of the feeding strategy of Apple snails from the water free surface, called surface film feeding, is being studied motivated by the need to develop new techniques to recover oil spills. To feed on floating food (usually a thin layer of microorganisms), the apple snail forms a funnel with its foot and pulls the free surface toward the funnel. High speed imaging and particle image velocimetry were used in the present investigation to measure the free surface motion and to investigate the mechanism used by the apple snails to pull the free surface. The results suggest that the snail pulls the free surface via the wavy motion of the muscles in its funnel.

High performance flight computer developed for deep space applications

NASA Technical Reports Server (NTRS)

Bunker, Robert L.

1993-01-01

The development of an advanced space flight computer for real time embedded deep space applications which embodies the lessons learned on Galileo and modern computer technology is described. The requirements are listed and the design implementation that meets those requirements is described. The development of SPACE-16 (Spaceborne Advanced Computing Engine) (where 16 designates the databus width) was initiated to support the MM2 (Marine Mark 2) project. The computer is based on a radiation hardened emulation of a modern 32 bit microprocessor and its family of support devices including a high performance floating point accelerator. Additional custom devices which include a coprocessor to improve input/output capabilities, a memory interface chip, and an additional support chip that provide management of all fault tolerant features, are described. Detailed supporting analyses and rationale which justifies specific design and architectural decisions are provided. The six chip types were designed and fabricated. Testing and evaluation of a brass/board was initiated.

The impact of the night float system on internal medicine residency programs.

PubMed

Trontell, M C; Carson, J L; Taragin, M I; Duff, A

1991-01-01

To study the design, method of implementation, perceived benefits, and problems associated with a night float system. Self-administered questionnaire completed by program directors, which included both structured and open-ended questions. The answers reflect resident and student opinions as well as those of the program directors, since program directors regularly obtain feedback from these groups. The 442 accredited internal medicine residency programs listed in the 1988-89 Directory of Graduate Medical Education Programs. Of the 442 programs, 79% responded, and 30% had experience with a night float system. The most frequent methods for initiating a night float system included: decreasing elective time (42.3%), hiring more residents (26.9%), creating a non-teaching service (12.5%), and reallocating housestaff time (9.6%). Positive effects cited include decreased fatigue, improved housestaff morale, improved recruiting, and better attitude toward internal medicine training. The quality of medical care was considered the same or better by most programs using it. The most commonly cited problems were decreased continuity of care, inadequate teaching of the night float team, and miscommunication. Residency programs using a night float system usually observe a positive effect on housestaff morale, recruitment, and working hours and no detrimental effect on the quality of patient care. Miscommunication and inadequate learning experience for the night float team are important potential problems. This survey suggests that the night float represents one solution to reducing resident working hours.

Cheerios Effect Controlled by Electrowetting.

PubMed

Yuan, Junqi; Feng, Jian; Cho, Sung Kwon

2015-08-04

The Cheerios effect is a common phenomenon in which small floating objects are either attracted or repelled by the sidewall due to capillary interaction. This attractive or repulsive behavior is highly dependent on the slope angles (angles of the interface on the wall or floating object with respect to a horizontal line) that can be mainly controlled by the wettability of the wall and floating object and the density of the object. In this paper, electrowetting on dielectric (EWOD) is implemented to the wall or floating object in order to actively control the wettability and thus capillary interaction. As such, the capillary force on buoyant and dense floating objects can be easily switched between repulsion and attraction by simply applying an electrical input. In addition, the theoretical prediction for the capillary force is verified experimentally by measuring the motion of floating particle and the critical contact angle on the wall at which the capillary force changes from attraction to repulsion. This successive verification is enabled by the merit of EWOD that allows for continuous change in the contact angle. Finally, the control method is extended to continuously move a floating object along a linear path and to continuously rotate a dumbbell-like floating object in centimeter scales using arrays of EWOD electrodes. A continuous linear motion is also accomplished in a smaller scale where the channel width (3 mm) is comparable to the capillary length.

Preformulation studies and optimization of sodium alginate based floating drug delivery system for eradication of Helicobacter pylori.

PubMed

Diós, Péter; Nagy, Sándor; Pál, Szilárd; Pernecker, Tivadar; Kocsis, Béla; Budán, Ferenc; Horváth, Ildikó; Szigeti, Krisztián; Bölcskei, Kata; Máthé, Domokos; Dévay, Attila

2015-10-01

The aim of this study was to design a local, floating, mucoadhesive drug delivery system containing metronidazole for Helicobacter pylori eradication. Face-centered central composite design (with three factors, in three levels) was used for evaluation and optimization of in vitro floating and dissolution studies. Sodium alginate (X1), low substituted hydroxypropyl cellulose (L-HPC B1, X2) and sodium bicarbonate (X3) concentrations were the independent variables in the development of effervescent floating tablets. All tablets showed acceptable physicochemical properties. Statistical analysis revealed that tablets with 5.00% sodium alginate, 38.63% L-HPC B1 and 8.45% sodium bicarbonate content showed promising in vitro floating and dissolution properties for further examinations. Optimized floating tablets expressed remarkable floating force. Their in vitro dissolution studies were compared with two commercially available non-floating metronidazole products and then microbiologically detected dissolution, ex vivo detachment force, rheological mucoadhesion studies and compatibility studies were carried out. Remarkable similarity (f1, f2) between in vitro spectrophotometrically and microbiologically detected dissolutions was found. Studies revealed significant ex vivo mucoadhesion of optimized tablets, which was considerably increased by L-HPC. In vivo X-ray CT studies of optimized tablets showed 8h gastroretention in rats represented by an animation prepared by special CT technique. Copyright © 2015 Elsevier B.V. All rights reserved.

A comparison of methods for estimating open-water evaporation in small wetlands

USGS Publications Warehouse

Masoner, Jason R.; Stannard, David I.

2010-01-01

We compared evaporation measurements from a floating pan, land pan, chamber, and the Priestley-Taylor (PT) equation. Floating pan, land pan, and meteorological data were collected from June 6 to July 21, 2005, at a small wetland in the Canadian River alluvium in central Oklahoma, USA. Evaporation measured with the floating pan compared favorably to 12 h chamber measurements. Differences between chamber and floating pan rates ranged from −0.2 to 0.3 mm, mean of 0.1 mm. The difference between chamber and land pan rates ranged from 0.8 to 2.0 mm, mean of 1.5 mm. The mean chamber-to-floating pan ratio was 0.97 and the mean chamber-to-land pan ratio was 0.73. The chamber-to-floating pan ratio of 0.97 indicates the use of a floating pan to measure evaporation in small limited-fetch water bodies is an appropriate and accurate method for the site investigated. One-sided Paired t-Tests indicate daily floating pan rates were significantly less than land pan and PT rates. A two-sided Paired t-Test indicated there was no significant difference between land pan and PT values. The PT equation tends to overestimate evaporation during times when the air is of low drying power and tends to underestimate as drying power increases.

Influence of different types of low substituted hydroxypropyl cellulose on tableting, disintegration, and floating behaviour of floating drug delivery systems

PubMed Central

Diós, Péter; Pernecker, Tivadar; Nagy, Sándor; Pál, Szilárd; Dévay, Attila

2014-01-01

The object of the present study is to evaluate the effect of application of low-substituted hydroxypropyl cellulose (L-HPC) 11 and B1 as excipients promoting floating in gastroretentive tablets. Directly compressed tablets were formed based on experimental design. Face-centred central composite design was applied with two factors and 3 levels, where amount of sodium alginate (X1) and L-HPC (X2) were the numerical factors. Applied types of L-HPCs and their 1:1 mixture were included in a categorical factor (X3). Studied parameters were floating lag time, floating time, floating force, swelling behaviour of tablets and dissolution of paracetamol, which was used as a model active substance. Due to their physical character, L-HPCs had different water uptake and flowability. Lower flowability and lower water uptake was observed after 60 min at L-HPC 11 compared to L-HPC B1. Shorter floating times were detected at L-HPC 11 and L-HPC mixtures with 0.5% content of sodium alginate, whereas alginate was the only significant factor. Evaluating results of drug release and swelling studies on floating tablets revealed correlation, which can serve to help to understand the mechanism of action of L-HPCs in the field development of gastroretentive dosage forms. PMID:26702261

Global maps of the magnetic thickness and magnetization of the Earth's lithosphere

NASA Astrophysics Data System (ADS)

Vervelidou, Foteini; Thébault, Erwan

2015-10-01

We have constructed global maps of the large-scale magnetic thickness and magnetization of Earth's lithosphere. Deriving such large-scale maps based on lithospheric magnetic field measurements faces the challenge of the masking effect of the core field. In this study, the maps were obtained through analyses in the spectral domain by means of a new regional spatial power spectrum based on the Revised Spherical Cap Harmonic Analysis (R-SCHA) formalism. A series of regional spectral analyses were conducted covering the entire Earth. The R-SCHA surface power spectrum for each region was estimated using the NGDC-720 spherical harmonic (SH) model of the lithospheric magnetic field, which is based on satellite, aeromagnetic, and marine measurements. These observational regional spectra were fitted to a recently proposed statistical expression of the power spectrum of Earth's lithospheric magnetic field, whose free parameters include the thickness and magnetization of the magnetic sources. The resulting global magnetic thickness map is compared to other crustal and magnetic thickness maps based upon different geophysical data. We conclude that the large-scale magnetic thickness of the lithosphere is on average confined to a layer that does not exceed the Moho.

The response of pile-guided floats subjected to dynamic loading.

DOT National Transportation Integrated Search

2014-08-01

Pile-Guided floats can be a desirable alternative to stationary berthing structures. Both floats and guide piles are subjected to dynamic : forces such as wind generated waves and impacts from vessels. This project developed a rational basis for esti...

On some physical and dynamical properties of microplastic particles in marine environment.

PubMed

Chubarenko, I; Bagaev, A; Zobkov, M; Esiukova, E

2016-07-15

Simplified physical models and geometrical considerations reveal general physical and dynamical properties of microplastic particles (0.5-5mm) of different density, shape and size in marine environment. Windage of extremely light foamed particles, surface area and fouling rate of slightly positively buoyant microplastic spheres, films and fibres and settling velocities of negatively buoyant particles are analysed. For the Baltic Sea dimensions and under the considered idealised external conditions, (i) only one day is required for a foamed polystyrene particle to cross the sea (ca. 250km); (ii) polyethylene fibres should spend about 6-8months in the euphotic zone before sinking due to bio-fouling, whilst spherical particles can be retained on the surface up to 10-15years; (iii) for heavy microplastic particles, the time of settling through the water column in the central Gotland basin (ca. 250m) is less than 18h. Proper physical setting of the problem of microplastics transport and developing of physically-based parameterisations are seen as applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

Reevaluation of microplastics extraction efficiency with the aim of Munich Plastic Sediment Separator.

NASA Astrophysics Data System (ADS)

Zobkov, Mikhail; Esiukova, Elena; Grave, Aleksei; Khatmullina, Liliya

2017-04-01

Invading of microplastics into marine environment is known as a global ecological threat. Specific density of microplastics can vary significantly depending on a polymer type, technological processes of its production, additives, weathering, and biofouling. Plastic particles can sink or float on the sea surface, but with time, most of drifting plastics become negatively buoyant and sink to the sea floor due to biofouling or adherence of denser particles. As a result, the seabed becomes the ultimate repository for microplastic particles and fibres. A study of microplastics content in aquatic sediments is an important source of information about ways of their migration, sink and accumulation zones. The Munich Plastic Sediment Separator (MPSS), proposed by Imhoff et al. (2012), is considered as the most effective tool for microplastic extraction. However, we observed that the numbers of marine microplastics extracted with this tool from different kinds of bottom sediments were significantly underestimated. We examined the extraction efficiency of the MPSS by adding artificial reference particles (ARPs) to marine sediment sample before the extraction procedure. Extraction was performed by two different methods: the modified NOAA method and using the MPSS. The separation solution with specific density 1.5 g/ml was used. Subsequent cleaning, drying and microscope detection procedures were identical. The microplastics content was determined in supernatant fraction, in the bulk of the extraction solution, in spoil dump fraction of MPSS and in instrument wash-out. While the extraction efficiency from natural sediments of ARPs by the MPSS was really high (100% in most cases), the extraction efficiency of marine microplastics was up to 10 times lower than that obtained with modified NOAA method for the same samples. Less than 40% of the total marine microplastics content has been successfully extracted with the MPSS. Large amounts of marine microplastics were found in the spoil dump and in the bulk solution fractions of the MPSS. Changes in stirring and separation periods had weak impact on the extraction efficiency of ARPs and marine microplastics. Until now, we are unable to find effective working procedures for adequate extraction of marine microplastics with the MPSS. The MPSS was found to be a useful tool for microplastics extraction from large sediment samples for qualitative analysis and to obtain examination specimens. Applying the MPSS for quantitative microplastics analysis requires further testing and elaboration of standardized extraction procedures. The research is supported by the Russian Science Foundation, grant number 15-17-10020 (project MARBLE). Imhof, H. K., Schmid, J., Niessner, R., Ivleva, N. P., Laforsch, C. 2012. A novel, highly efficient method for the separation and quantification of plastic particles in sediments of aquatic environments. Limnology and Oceanography: Methods, 10(7), 524-537. DOI 10.4319/lom.2012.10.524

Floating arterial thrombus related stroke treated by intravenous thrombolysis.

PubMed

Vanacker, P; Cordier, M; Janbieh, J; Federau, C; Michel, P

2014-01-01

The effects of intravenous thrombolysis on floating thrombi in cervical and intracranial arteries of acute ischemic stroke patients are unknown. Similarly, the best prevention methods of early recurrences remain controversial. This study aimed to describe the clinical and radiological outcome of thrombolyzed strokes with floating thrombi. We retrospectively analyzed all thrombolyzed stroke patients in our institution between 2003 and 2010 with floating thrombi on acute CT-angiography before the intravenous thrombolysis. The floating thrombus was diagnosed if an elongated thrombus of at least 5 mm length, completely surrounded by contrast on supra-aortic neck or intracerebral arteries, was present on CT-angiography. Demographics, vascular risk factors, and comorbidities were recorded and stroke etiology was determined after a standardized workup. Repeat arterial imaging was performed by CTA at 24 h or before if clinical worsening was noted and then by Doppler and MRA during the first week and at four months. Of 409 thrombolyzed stroke patients undergoing acute CT Angiography, seven (1.7%) had a floating thrombus; of these seven, six had it in the anterior circulation. Demographics, risk factors and stroke severity of these patients were comparable to the other thrombolyzed patients. After intravenous thrombolysis, the floating thrombi resolved completely at 24 h in four of the patients, whereas one had an early recurrent stroke and one developed progressive worsening. One patient developed early occlusion of the carotid artery with floating thrombus and subsequently a TIA. The two patients with a stable floating thrombus had no clinical recurrences. In the literature, only one of four reported cases were found to have a thrombolysis-related early recurrence. Long-term outcome seemed similar in thrombolyzed patients with floating thrombus, despite a possible increase of very early recurrence. It remains to be established whether acute mechanical thrombectomy could be a safer and more effective treatment to prevent early recurrence. However, intravenous thrombolysis should not be withheld in eligible stroke patients. © 2014 S. Karger AG, Basel.

Air-Deployable Profiling Floats for Tropical Cyclone Research

NASA Astrophysics Data System (ADS)

Jayne, S. R.; Robbins, P.; Owens, B.; Ekholm, A.; Dufour, J. E.; Sanabia, E.

2016-02-01

The development of a smaller profiling float that can be launched from Hurricane Hunter aircraft offers the opportunity to monitor the upper-ocean thermal structure over a time span of many months. These Argo-type profiling floats can be deployed in advance of, or during, a tropical cyclone from any aircraft equipped with an A-sized (AXBT) launch tube, or from the stern ramp of a C-130. The floats have the same dimensions as an AXBT and weigh about 8.5 kg. Upon deployment, the floats parachute to the surface, detach and automatically begin their programmed mission. The recorded temperature data is averaged over 1-meter bins that are reported back via the Iridium satellite phone network, which is then automatically processed and posted to the GTS. The floats are also reprogrammable via the 2-way communication afforded by Iridium. We report on the results of deployments during the 2014 and 2015 hurricane seasons. Unique observations of the ocean response from Hurricane Ignacio are particularly noteworthy and will be presented. Further plans for continued development of floats include measuring salinity (from an inductive conductivity sensor) and observations of the surface wave field (measured by an onboard accelerometer) will also be described.

Calculating surface ocean pCO2 from biogeochemical Argo floats equipped with pH: An uncertainty analysis

NASA Astrophysics Data System (ADS)

Williams, N. L.; Juranek, L. W.; Feely, R. A.; Johnson, K. S.; Sarmiento, J. L.; Talley, L. D.; Dickson, A. G.; Gray, A. R.; Wanninkhof, R.; Russell, J. L.; Riser, S. C.; Takeshita, Y.

2017-03-01

More than 74 biogeochemical profiling floats that measure water column pH, oxygen, nitrate, fluorescence, and backscattering at 10 day intervals have been deployed throughout the Southern Ocean. Calculating the surface ocean partial pressure of carbon dioxide (pCO2sw) from float pH has uncertainty contributions from the pH sensor, the alkalinity estimate, and carbonate system equilibrium constants, resulting in a relative standard uncertainty in pCO2sw of 2.7% (or 11 µatm at pCO2sw of 400 µatm). The calculated pCO2sw from several floats spanning a range of oceanographic regimes are compared to existing climatologies. In some locations, such as the subantarctic zone, the float data closely match the climatologies, but in the polar Antarctic zone significantly higher pCO2sw are calculated in the wintertime implying a greater air-sea CO2 efflux estimate. Our results based on four representative floats suggest that despite their uncertainty relative to direct measurements, the float data can be used to improve estimates for air-sea carbon flux, as well as to increase knowledge of spatial, seasonal, and interannual variability in this flux.

Design and in vitro evaluation of multiparticulate floating drug delivery system of zolpidem tartarate.

PubMed

Amrutkar, P P; Chaudhari, P D; Patil, S B

2012-01-01

Zolpidem tartarate is a non-benzodiazepine, sedative-hypnotic, which finds its major use in various types of insomnia. The present work relates to development of multiparticulate floating drug delivery system based on gas generation technique to prolong the gastric residence time and to increase the overall bioavailability. Modified release dosage form of zolpidem tartarate adapted to release over a predetermined time period, according to biphasic profile of dissolution, where the first phase is immediate release phase for inducing the sleep and the second phase is modified release phase for maintaining the sleep up to 10 h. The system consists of zolpidem tartarate layered pellets coated with effervescent layer and polymeric membrane. The floating ability and in vitro drug release of the system were dependent on amount of the effervescent agent (sodium bicarbonate) layered onto the drug layered pellets, and coating level of the polymeric membrane (Eudragit(®) NE 30D). The system could float completely within 5 min and maintain the floating over a period of 10 h. The multiparticulate floating delivery system of zolpidem tartarate with rapid floating and modified drug release was obtained. Copyright © 2011 Elsevier B.V. All rights reserved.

Formulation and evaluation of non-effervescent floating tablets of losartan potassium.

PubMed

Getyala, Anil; Gangadharappa, H V; Prasad, M Sarat Chandra; Reddy, M Praveen Kumar; Kumar, T M Pramod

2013-10-01

The aim of the work is to modify the solubility and bioavailability of Losartan potassium, by employing noneffervescent floating drug delivery (tablet dosage forms). Non-effervescent systems are a type of floating drug delivery systems, that have been used to boost the gastric residence and the floatation time in the gastro intestinal tract. The study included formulation of floating tablets using polymers like Chitosan and Karaya gum as matrix forming agents. Accurel(®) MP 1000 was used as floating agent. The tablets were prepared by direct compression technique. FTIR, DSC studies conformed that there was no incompatibility between the polymer and the drug. Tablet preformulation parameters were within the Pharmacopoeial limit. Tablet showed zero lag time, contisnuance of buoyancy for >12 h. The tablet showed good in vitro release. Drug release was through swelling and abided by the gellation mechanism. In vivo X-ray studies depicted that tablets continued to float in the GIT for 12 h. Accelerated stability showed that, tablets were stable for over 6 month. Thus the prepared non-effervescent floating tablet of Losartan potassium can be used for the treatment of hypertension for more than 12 h with single dose administration.

Advanced ADA Workshop Held in Biloxi, Mississippi on 24-27 January 1989

DTIC Science & Technology

1989-01-27

Software Engineering (Break at 2:30j 6:30-8:00 Keesler AFB Reception Officers’ Club WEDNESDAY - 25 JANIJ1APY 9:00-12:00 Bldc 1002 Generics (Break at 10...TextIO.FileType: -- NO! procedure Wrong; -- problem is FileType is limited private Object Parameters A More Useful Example generic Control -Block : in out... control the precision used Float Type Parameters An Example generic type FloatType is digits <>; function Sqrt(X : FloatType) return FloatType