Sample records for axis marine current

  1. The Development of Duct for a Horizontal Axis Turbine Using CFD

    NASA Astrophysics Data System (ADS)

    Ghani, Mohamad Pauzi Abdul; Yaacob, Omar; Aziz, Azliza Abdul

    2010-06-01

    Malaysia is heavily dependent on the fossil fuels to satisfy its energy demand. Nowadays, renewable energy which has attracted great interest is marine current energy, which extracted by a device called a device called marine current turbine. This energy resource has agreat potential to be exploited on a large scale because of its predictability and intensity. This paper will focus on developing a Horizontal Axis Marine Current Turbine (HAMCT) rotor to extract marine current energy suitable for Malaysian sea conditions. This work incorporates the characteristic of Malaysia's ocean of shallow water and low speed current in developing the turbines. The HAMCT rotor will be developed and simulated using CAD and CFD software for various combination of inlet and oulet duct design. The computer simulation results of the HAMCT being developed will be presented.

  2. Experiments on the magnetic coupling in a small scale counter rotating marine current turbine

    NASA Astrophysics Data System (ADS)

    Kim, I. C.; Lee, N. J.; Wata, J.; Hyun, B. S.; Lee, Y. H.

    2016-05-01

    Modern economies are dependent on energy consumption to ensure growth or sustainable development. Renewable energy sources provide a source of energy that can provide energy security and is renewable. Tidal energy is more predictable than other sources or renewable energy like the sun or wind. Horizontal axis marine current turbines are currently the most advanced and commercially feasible option for tidal current convertors. A dual rotor turbine is theoretically able to produce more power than a single rotor turbine at the same fluid velocity. Previous experiments for a counter rotating dual rotor horizontal axis marine current turbine used a mechanical oil seal coupling that caused mechanical losses when water entered through small gaps at the shaft. A new magnetic coupling assembly eliminates the need for a shaft to connect physically with the internal mechanisms and is water tight. This reduces mechanical losses in the system and the effect on the dual rotor performance is presented in this paper.

  3. State of the art in protection of erosion-corrosion on vertical axis tidal current turbine

    NASA Astrophysics Data System (ADS)

    Musabikha, Siti; Utama, I. Ketut Aria Pria; Mukhtasor

    2018-05-01

    Vertical axis tidal current turbine is main part of ocean energy devices which converts the tidal current energy into electricity. Its development is arising too due to increased interest research topic concerning climate change mitigation. Due to its rotating movement, it will be induced mechanical forces, such as shear stress and/or particle impact. Because of its natural operations, vertical axis turbine is also being exposed to harsh and corroding marine environment itself. In order to secure the vertical tidal turbine devices from mechanical wear and corrosion effects which is lead to a material loss, an appropriate erosion-corrosion protection needs to be defined. Its protection actionscan be derived such as design factors, material selections, inhibitors usage, cathodic protections, and coatings. This paper aims to analyze protection method which is necessary to control erosion-corrosion phenomenon that appears to the vertical axis tidal current turbine.

  4. Coherent Structure Dynamics and Turbulent Effects of Horizontal Axis Marine Energy Devices

    NASA Astrophysics Data System (ADS)

    Gajardo, D. I.; Escauriaza, C. R.; Ingram, D.

    2016-12-01

    Harnessing the energy available in the oceans constitutes one of the most promising alternatives for generating clean electricity. There are vast amounts of energy present both in waves and tidal currents so it is anticipated that marine energy will have a major role in non-conventional renewable energy generation in the near to mid future. Nevertheless, before marine hydrokinetic (MHK) devices can be installed in large numbers a better understanding of the physical, social and environmental implications of their operation is needed. This includes understanding the: hydrodynamic processes, interaction with bathymetry, and the local flow characteristics. This study is focused on the effects horizontal axis MHK devices have on flow turbulence and coherent structures. This is especially relevant considering that sites with favourable conditions for MHK devices are tidal channels where a delicate balance exists between the strong tidal currents and the ecosystems. Understanding how MHK devices influence flow conditions, turbulence and energy flux is essential for predicting and assessing the environmental implications of deploying MHK technologies. We couple a Blade Element Momentum Actuator Disk (BEM-AD) model to a Detached Eddy Simulation (DES) flow solver in order to study flow conditions for different configurations of horizontal axis MHK turbines. In this study, we contribute to the understanding of the hydrodynamic behaviour of MHK technologies, and give insights into the effects devices will have on their environment, with emphasis in ambient turbulence and flow characteristics, while keeping in mind that these effects can alter electricity quality and device performance. Work supported by CONICYT grant 80160084, Fondecyt grant 1130940, Chile's Marine Energy Research & Innovation Center (MERIC) CORFO project 14CEI2-28228, and the collaboration between the Pontificia Universidad Católica de Chile and the University of Edinburgh, UK, partially supported by the RC UK Energy Programme's UK Centre for Marine Energy Research (EP/I027912/1).

  5. Wake Survey of a Marine Current Turbine Under Steady Conditions

    NASA Astrophysics Data System (ADS)

    Lust, Ethan; Luznik, Luksa; Flack, Karen

    2016-11-01

    A submersible particle image velocimetry (PIV) system was used to study the wake of a horizontal axis marine current turbine. The turbine was tested in a large tow tank facility at the United States Naval Academy. The turbine is a 1/25th scale model of the U.S. National Renewable Energy Laboratory's Reference Model 1 (RM1) tidal turbine. It is a two-bladed turbine measuring 0.8 m in diameter and featuring a NACA 63-618 airfoil cross section. Separate wind tunnel testing has shown the foil section used on the turbine to be Reynolds number independent with respect to lift at the experimental parameters of tow carriage speed (Utow = 1 . 68 m/s) and tip speed ratio (TSR = 7). The wake survey was conducted over an area extending 0.25D forward of the turbine tip path to 2.0D aft, and to a depth of 1.0D beneath the turbine output shaft in the streamwise plane. Each field of view was approximately 30 cm by 30 cm, and each overlapped the adjacent fields of view by 5 cm. The entire flow field was then reconstructed into a single field of investigation. Results include streamwise and vertical ensemble average velocity fields averaged over approximately 1,000 realizations, as well as higher-order statistics. Turbine tip vortex centers were identified and plotted showing increasing aperiodicity with wake age. keywords: horizontal axis marine current turbine, particle image velocimetry, towing tank, wake survey

  6. The Influence of Surface Gravity Waves on Marine Current Turbine Performance

    NASA Astrophysics Data System (ADS)

    Lust, E.; Luznik, L.; Flack, K. A.; Walker, J.; Van Benthem, M.

    2013-12-01

    Surface gravity waves can significantly impact operating conditions for a marine current turbine, imparting unsteady velocities several orders of magnitude larger than the ambient turbulence. The influence of surface waves on the performance characteristics of a two-bladed horizontal axis marine current turbine was investigated experimentally in a large towing tank facility at the United States Naval Academy. The turbine model had a 0.8 m diameter (D) rotor with a NACA 63-618 cross section, which is Reynolds number independent with respect to lift coefficient in the operating range of Rec ≈ 4 x 105. The torque, thrust and rotational speed were measured at a range of tip speed ratios (TSR) from 5 < TSR < 11. Tests were performed at two rotor depths (1.3D and 2.25D) with and without waves. The average turbine performance characteristics were largely unchanged by depth or the presence of waves. However, tests with waves indicate large variations in thrust, rotational speed, and torque occurred with the passage of the wave. These results demonstrate the impact of surface gravity waves on power production and structural loading and suggest that turbines should be positioned vertically within the water column at a depth which maximizes power output while minimizing material fatigue. Keywords-- marine current turbine, tidal turbine, towing-tank experiments, surface gravity waves, fatigue loading, phase averaging

  7. Unidirectional Core-Shell Hybrids for Concrete Reinforcement - A preliminary Study

    DTIC Science & Technology

    1994-02-01

    angle with respect to the rebar longitudinal axis. 14. SUBJECT TERMS 115. WNUMER OF PAGES FRP, rebar , concrete , fibers, carbon fibers, glass fibers...structures. The main cause of deterioration is concrete cracking and corrosion of steel reinforcement exposed to the marine environment and aggressive...agents such as deicing salts for bridges and pavements . To prevent this corrosion , galvanized and epoxy-coated steel reinforcing bars are currently being

  8. The Impact of Blade Roughness and Biofouling on the Performance of a Horizontal Axis Marine Current Turbine

    NASA Astrophysics Data System (ADS)

    Flack, Karen; Walker, Jessica; Schultz, Michael; Lust, Ethan

    2013-11-01

    The impact of blade roughness and biofouling on the performance of a two-bladed horizontal axis marine current turbine was investigated experimentally and numerically. A 0.8 m diameter rotor (1/25th scale) with a NACA 63-618 cross section was tested in a towing tank. The torque, thrust and rotational speed were measured in the range 5 < λ <11 (λ = tip speed ratio). Three different cases were tested: clean blades, artificially fouled blades and roughened blades. The performance of the turbine was predicted using Blade Element Momentum theory and validated using the experimental results. The lift and drag curves necessary for the numerical model were obtained by testing a 2D NACA 63-618 airfoil in a wind tunnel under clean and roughened conditions. The numerical model predicts the trends that were observed in the experimental data for roughened blades. The artificially fouled blades did not adversely affect turbine performance, as the vast majority of the fouling sheared off. For the case of roughened blades, the power coefficient (CP) versus λ curve was significantly offset below that for the clean case. The maximum CP for this condition was 0.34, compared to 0.42 for the clean condition. Work supported by Australian Fulbright Association and ONR.

  9. Torsionally rigid support apparatus for marine seismic transducer

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

    Myers, W.J.; Cole, J.H.

    1989-11-14

    This patent describes apparatus for supporting a marine seismic transducer from a vessel. It comprises: an elongated substantially rigid towing arm; a connector means for connecting the transducer to a lower end of the towing arm; a swivel member which is secured to the vessel and is pivotable about a generally horizontal first axis transverse to a length of the vessel; and a support means for pivotally connecting an upper end of the towing arm to the swivel member. The support means being pivotal relative to the swivel member about a second axis transverse to a longitudinal axis of themore » towing arm. The support means being substantially rigid so as to prevent any substantial rotation of the towing arm about its the longitudinal axis.« less

  10. Current Research Activities of the Department of Oceanography.

    DTIC Science & Technology

    1981-04-01

    being analyzed in terms of the structure of the East Pacific A multi-institutional investi- Rise at 12* N and the change in crus- gation on the abundance...seismic experiment at the axis of the East Pacific Rise . Marine Geology 35: 147-169. No. 1090 McDaniel, N . and K. Banse (1979) A novel method of...proceeded eastward from Tahiti ducted off the Oregon and Washington to the East Pacific Rise area, then coasts. In late August a return back to Tahiti. On

  11. Numerical Modeling and Experimental Analysis of Scale Horizontal Axis Marine Hydrokinetic (MHK) Turbines

    NASA Astrophysics Data System (ADS)

    Javaherchi, Teymour; Stelzenmuller, Nick; Seydel, Joseph; Aliseda, Alberto

    2013-11-01

    We investigate, through a combination of scale model experiments and numerical simulations, the evolution of the flow field around the rotor and in the wake of Marine Hydrokinetic (MHK) turbines. Understanding the dynamics of this flow field is the key to optimizing the energy conversion of single devices and the arrangement of turbines in commercially viable arrays. This work presents a comparison between numerical and experimental results from two different case studies of scaled horizontal axis MHK turbines (45:1 scale). In the first case study, we investigate the effect of Reynolds number (Re = 40,000 to 100,000) and Tip Speed Ratio (TSR = 5 to 12) variation on the performance and wake structure of a single turbine. In the second case, we study the effect of the turbine downstream spacing (5d to 14d) on the performance and wake development in a coaxial configuration of two turbines. These results provide insights into the dynamics of Horizontal Axis Hydrokinetic Turbines, and by extension to Horizontal Axis Wind Turbines in close proximity to each other, and highlight the capabilities and limitations of the numerical models. Once validated at laboratory scale, the numerical model can be used to address other aspects of MHK turbines at full scale. Supported by DOE through the National Northwest Marine Renewable Energy Center.

  12. Design, experimental analysis, and unsteady Reynolds-averaged Navier-Stokes simulation of laboratory-scale counter-rotating vertical-axis turbines in marine environment

    NASA Astrophysics Data System (ADS)

    Doan, Minh; Padricelli, Claudrio; Obi, Shinnosuke; Totsuka, Yoshitaka

    2017-11-01

    We present the torque and power measurement of laboratory-scale counter-rotating vertical-axis hydrokinetic turbines, built around a magnetic hysteresis brake as the speed controller and a Hall-effect sensor as the rotational speed transducer. A couple of straight-three-bladed turbines were linked through a transmission of spur gears and timing pulleys and coupled to the electronic instrumentation via flexible shaft couplers. A total of 8 experiments in 2 configurations were conducted in the water channel facility (4-m long, 0.3-m wide, and 0.15-m deep). Power generation of the turbines (0.06-m rotor diameter) was measured and compared with that of single turbines of the same size. The wakes generated by these experiments were also measured by particle image velocimetry (PIV) and numerically simulated by unsteady Reynolds-averaged Navier-Stokes (URANS) simulation using OpenFOAM. Preliminary results from wake measurement indicated the mechanism of enhanced power production behind the counter-rotating configuration of vertical-axis turbines. Current address: Politecnico di Milano.

  13. Influence of surface gravity waves on near wake development behind a towed model horizontal axis marine current turbine

    NASA Astrophysics Data System (ADS)

    Luznik, Luksa; Flack, Karen; Lust, Ethan

    2016-11-01

    2D PIV measurements in the near wake flow field (x/D<2) are presented for a 1/25 scale, 0.8 m diameter (D) two bladed horizontal axis tidal turbine. All measurements were obtained in the USNA 380 ft tow tank with turbine towed at a constant carriage speed (Utow = 1.68 m/s), at the nominal tip speed ratio (TSR) of 7 and incoming regular waves with a period of 2.3 seconds and 0.18 m wave height. Near wake mapping is accomplished by "tiling" phase locked individual 2D PIV fields of view (nominally 30x30 cm2) with approximately 5 cm overlap. The discussion will focus on the downstream evolution of coherent tip vortices shed by the rotor blades and their vertical/horizontal displacements by the wave induced fluctuations. This observed phenomena ultimately results in significantly increased downstream wake expansion in comparison with the same conditions without waves. Office of Naval Research.

  14. Near-surface Density Currents Observed in the Southeast Pacific Stratocumulus-topped Marine Boundary Layer

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

    Wilbanks, Matt C.; Yuter, S. E.; de Szoeke, S.

    2015-09-01

    Density currents (i.e. cold pools or outflows) beneath marine stratocumulus clouds are characterized using a 30-d data set of ship-based observations obtained during the 2008 Variability of American Monsoon Systems (VAMOS) Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) in the southeast Pacific. An objective method identifies 71 density current fronts using an air density criterion and isolates each density current’s core (peak density) and tail (dissipating) zone. Compared to front and core zones, most density current tails exhibited weaker density gradients and wind anomalies elongated about the axis of the mean wind. The mean cloud-level advection relative to the surface layer windmore » (1.9 m s-1) nearly matches the mean density current propagation speed (1.8 m s-1). The similarity in speeds allows drizzle cells to deposit tails in their wakes. Based on high-resolution scanning Doppler lidar data, prefrontal updrafts had a mean intensity of 0.91 m s-1, reached an average altitude of 800 m, and were often surmounted by low-lying shelf clouds not connected to the overlying stratocumulus cloud. Nearly 90% of density currents were identified when C-band radar estimated 30-km diameter areal average rain rates exceeded 1 mm d-1. Rather than peaking when rain rates are highest overnight, density current occurrence peaks between 0600 and 0800 local solar time when enhanced local drizzle co-occurs with shallow subcloud dry and stable layers. The dry layers may contribute to density current formation by enhancing subcloud evaporation of drizzle. Density currents preferentially occur in regions of open cells but also occur in regions of closed cells.« less

  15. Adaptive PI control strategy for flat permanent magnet linear synchronous motor vibration suppression

    NASA Astrophysics Data System (ADS)

    Meng, Fanwei; Liu, Chengying; Li, Zhijun; Wang, Liping

    2013-01-01

    Due to low damping ratio, flat permanent magnet linear synchronous motor's vibration is difficult to be damped and the accuracy is limited. The vibration suppressing results are not good enough in the existing research because only the longitudinal direction vibration is considered while the normal direction vibration is neglected. The parameters of the direct-axis current controller are set to be the same as those of the quadrature-axis current controller commonly. This causes contradiction between signal noise and response. To suppress the vibration, the electromagnetic force model of the flat permanent magnet synchronous linear motor is formulated first. Through the analysis of the effect that direct-axis current noise and quadrature-axis current noise have on both direction vibration, it can be declared that the conclusion that longitudinal direction vibration is only related to the quadrature-axis current noise while the normal direction vibration is related to both the quadrature-axis current noise and direct-axis current noise. Then, the simulation test on current loop with a low-pass filter is conducted and the results show that the low-pass filter can not suppress the vibration but makes the vibration more severe. So a vibration suppressing strategy that the proportional gain of direct-axis current controller adapted according to quadrature-axis reference current is proposed. This control strategy can suppress motor vibration by suppressing direct-axis current noise. The experiments results about the effect of K p and T i on normal direction vibration, longitudinal vibration and the position step response show that this strategy suppresses vibration effectively while the motor's motion performance is not affected. The maximum reduction of vibration can be up to 40%. In addition, current test under rated load condition is also conducted and the results show that the control strategy can avoid the conflict between the direct-axis current and the quadrature-axis current under typical load. Adaptive PI control strategy can effectively suppress the flat permanent magnet linear synchronous motor's vibration without affecting the motor's performance.

  16. Numerical Simulations of Marine Hydrokinetic (MHK) Turbines Using the Blade Element Momentum Theory

    NASA Astrophysics Data System (ADS)

    Javaherchi, Teymour; Thulin, Oskar; Aliseda, Alberto

    2011-11-01

    Energy extraction from the available kinetic energy in tidal currents via Marine Hydrokinetic (MHK) turbines has recently attracted scientists' attention as a highly predictable source of renewable energy. The strongest tidal resources have a concentrated nature that require close turbine spacing in a farm of MHK turbines. This tight spacing, however, will lead to interaction of the downstream turbines with the turbulent wake generated by upstream turbines. This interaction can significantly reduce the power generated and possibly result in structural failure before the expected service life is completed. Development of a numerical methodology to study the turbine-wake interaction can provide a tool for optimization of turbine spacing to maximize the power generated in turbine arrays. In this work, we will present numerical simulations of the flow field in a farm of horizontal axis MHK turbines using the Blade Element Momentum Theory (BEMT). We compare the value of integral variables (i.e. efficiency, power, torque and etc.) calculated for each turbine in the farm for different arrangements with varying streamwise and lateral offsets between turbines. We find that BEMT provides accurate estimates of turbine efficiency under uniform flow conditions, but overpredicts the efficiency of downstream turbines when they are strongly affected by the wakes. Supported by DOE through the National Northwest Marine Renewable Energy Center.

  17. Development of a towing tank PIV system and a wake survey of a marine current turbine under steady conditions

    NASA Astrophysics Data System (ADS)

    Lust, Ethan; Luznik, Luksa; Flack, Karen

    2015-11-01

    A submersible particle image velocimetry (PIV) system was designed and built at the U.S. Naval Academy. The system was used to study the wake of a scale-independent horizontal axis marine current turbine. The turbine is a 1/25th scale model of the U.S. National Renewable Energy Laboratory's Reference Model 1 (RM1) tidal turbine. It is a two-bladed turbine measuring 0.8 m in diameter and featuring a NACA 63-618 airfoil cross-section. The wake survey was conducted over an area extending 0.25D forward of the turbine tip path to 2.0D aft to a depth of 1.0D beneath the turbine output shaft in the streamwise plane. Each field of view was approximately 30 cm by 30 cm, and each overlapped the adjacent fields of view by 5 cm. The entire flow field was then reconstructed by registering the resultant vector fields together into a single field of investigation. Results include the field of investigation from a representative case, for the mean velocity field averaged over approximately 1,000 realizations, and turbulent statistics including turbulence intensities, Reynolds shear stresses, and turbulent kinetic energy. This research was funded by the Office of Naval Research.

  18. Device for passive flow control around vertical axis marine turbine

    NASA Astrophysics Data System (ADS)

    Coşoiu, C. I.; Georgescu, A. M.; Degeratu, M.; Haşegan, L.; Hlevca, D.

    2012-11-01

    The power supplied by a turbine with the rotor placed in a free stream flow may be increased by augmenting the velocity in the rotor area. The energy of the free flow is dispersed and it may be concentrated by placing a profiled structure around the bare turbine in order to concentrate more energy in the rotor zone. At the Aerodynamic and Wind Engineering Laboratory (LAIV) of the Technical University of Civil Engineering of Bucharest (UTCB) it was developed a concentrating housing to be used for hydro or aeolian horizontal axis wind turbines, in order to increase the available energy in the active section of turbine rotor. The shape of the concentrating housing results by superposing several aero/hydro dynamic effects, the most important being the one generated by the passive flow control devices that were included in the housing structure. Those concentrating housings may be also adapted for hydro or aeolian turbines with vertical axis. The present paper details the numerical research effectuated at the LAIV to determine the performances of a vertical axis marine turbine equipped with such a concentrating device, in order to increase the energy quantity extracted from the main flow. The turbine is a Darrieus type one with three vertical straight blades, symmetric with respect to the axis of rotation, generated using a NACA4518 airfoil. The global performances of the turbine equipped with the concentrating housing were compared to the same characteristics of the bare turbine. In order to validate the numerical approach used in this paper, test cases from the literature resulting from experimental and numerical simulations for similar situations, were used.

  19. A 20-KW Wind Energy Conversion System (WECS) at the Marine Corps Air Station, Kaneohe, Hawaii.

    DTIC Science & Technology

    1983-01-01

    of propellers and that vertical-axis wind turbines would be more efficient. Several turbines such as the Darrieus and gyro-mill, of this type are... wind turbines , wind systems siting, alternate energy systems, remote site power generation. 20 ABSTRACT (Con!,,u,. - r r... .. do I(3 lI - d #,d e...Corps Air Station (MCAS) Kaneohe Bay, Hawaii. The wind turbine generator chosen for the evaluation was a horizontal-axis-propeller- downwind rotor

  20. Multi-model Ensemble of Ocean Data Assimilation Products in The Northwestern Pacific and Their Quality Assessment

    NASA Astrophysics Data System (ADS)

    Isoguchi, O.; Matsui, K.; Kamachi, M.; Usui, N.; Miyazawa, Y.; Ishikawa, Y.; Hirose, N.

    2017-12-01

    Several operational ocean assimilation models are currently available for the Northwestern Pacific and surrounding marginal seas. One of the main targets is predicting the Kuroshio/Kuroshio Extension, which have an impact not only on social activities, such as fishery and ship routing, but also on local weather. There is a demand to assess their quality comprehensively and make the best out the available products. In the present study, several ocean data assimilation products and their multi-ensemble product were assessed by comparing with satellite-derived sea surface temperature (SST), sea surface height (SSH), and in-situ hydrographic sections. The Kuroshio axes were also computed from the surface currents of these products and were compared with the Kuroshio Axis data produced analyzing satellite-SST, SSH, and in-situ observations by Marine Information Research Center (MIRC). The multi-model ensemble products generally showed the best accuracy in terms of the comparisons with the satellite-derived SST and SSH. On the other hand, the ensemble products didn't result in the best one in the comparison with the hydrographic sections. It is thus suggested that the multi-model ensemble works efficiently for the horizontally 2D parameters for which each assimilation product tends to have random errors while it does not work well for the vertical 2D comparisons for which it tends to have bias errors with respect to in-situ data. In the assessment with the Kuroshio Axis Data, some products showed more energetic behavior than the Kuroshio Axis data, resulting in the large path errors which are defined as a ratio between an area surrounded by the reference and model-derived ones and a path length. It is however not determined which are real, because in-situ observations are still lacking to resolve energetic Kuroshio behavior even though the Kuroshio is one of the strongest current.

  1. Chronic Exposure of Marine Medaka (Oryzias melastigma) to 4,5-Dichloro-2-n-octyl-4-isothiazolin-3-one (DCOIT) Reveals Its Mechanism of Action in Endocrine Disruption via the Hypothalamus-Pituitary-Gonadal-Liver (HPGL) Axis.

    PubMed

    Chen, Lianguo; Zhang, Weipeng; Ye, Rui; Hu, Chenyan; Wang, Qiangwei; Seemann, Frauke; Au, Doris W T; Zhou, Bingsheng; Giesy, John P; Qian, Pei-Yuan

    2016-04-19

    In this study, marine medaka (Oryzias melastigma) were chronically exposed for 28 days to environmentally realistic concentrations of 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (DCOIT) (0, 0.76, 2.45, and 9.86 μg/L), the active ingredient in commercial antifouling agent SeaNine 211. Alterations of the hypothalamus-pituitary-gonadal-liver (HPGL) axis were investigated across diverse levels of biological organization to reveal the underlying mechanisms of its endocrine disruptive effects. Gene transcription analysis showed that DCOIT had positive regulatory effects mainly in male HPGL axis with lesser extent in females. The stimulated steroidogenic activities resulted in increased concentrations of steroid hormones, including estradiol (E2), testosterone (T), and 11-KT-testosterone (11-KT), in the plasma of both sexes, leading to an imbalance in hormone homeostasis and increased E2/T ratio. The relatively estrogenic intracellular environment in both sexes induced the hepatic synthesis and increased the liver and plasma content of vitellogenin (VTG) or choriogenin. Furthermore, parental exposure to DCOIT transgenerationally impaired the viability of offspring, as supported by a decrease in hatching and swimming activity. Overall, the present results elucidated the estrogenic mechanisms along HPGL axis for the endocrine disruptive effects of DCOIT. The reproductive impairments of DCOIT at environmentally realistic concentrations highlights the need for more comprehensive investigations of its potential ecological risks.

  2. Numerical simulation of a cross flow Marine Hydrokinetic turbine.

    NASA Astrophysics Data System (ADS)

    Hall, Taylor; Aliseda, Alberto

    2011-11-01

    In the search for alternative sources of energy, the kinetic energy of water currents in oceans, rivers and estuaries is being explored as predictable and environmentally benign. We are investigating the flow past a cross flow turbine in which a helical blade under hydrodynamic forces turns around a shaft perpendicular to the free stream. This type of turbine, while very different from the classical horizontal axis turbine commonly used in the wind energy field, presents advantages for stacking in very narrow constricted channels where the water currents are consistently high and therefore turbine installation may be economically feasible. We use a model of a helical four-bladed turbine in cross flow to investigate the efficiency of the energy capture and the dynamics of the turbulent wake. Scale model experiments in a flume are used to validate the numerical results on a stationary configuration as an initial step towards creating an accurate numerical model of the turbine. The simulation of the rotating turbine provides a full perspective on the effect of angular position on flow detachment and vortex shedding from the blade, as well as on the fluctuations of the shaft torque produced (a problematic feature of this type of turbine). The results are analyzed in terms of hydrodynamic optimization of the blade and its structural loading. Supported by DOE through the Northwest National Marine Renewable Energy Center.

  3. Three-dimensional Numerical Analysis on Blade Response of Vertical Axis Tidal Current Turbine Under Operational Condition

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

    Li, Ye; Karri, Naveen K.; Wang, Qi

    Tidal power as a large-scale renewable source of energy has been receiving significant attention recently because of its advantages over the wind and other renewal energy sources. The technology used to harvest energy from tidal current is called a tidal current turbine. Though some of the principles of wind turbine design are applicable to tidal current turbines, the design of latter ones need additional considerations like cavitation damage, corrosion etc. for the long-term reliability of such turbines. Depending up on the orientation of axis, tidal current turbines can be classified as vertical axis turbines or horizontal axis turbines. Existing studiesmore » on the vertical axis tidal current turbine focus more on the hydrodynamic aspects of the turbine rather than the structural aspects. This paper summarizes our recent efforts to study the integrated hydrodynamic and structural aspects of the vertical axis tidal current turbines. After reviewing existing methods in modeling tidal current turbines, we developed a hybrid approach that combines discrete vortex method -finite element method that can simulate the integrated hydrodynamic and structural response of a vertical axis turbine. This hybrid method was initially employed to analyze a typical three-blade vertical axis turbine. The power coefficient was used to evaluate the hydrodynamic performance, and critical deflection was considered to evaluate the structural reliability. A sensitivity analysis was also conducted with various turbine height-to-radius ratios. The results indicate that both the power output and failure probability increase with the turbine height, suggesting a necessity for optimal design. An attempt to optimize a 3-blade vertical axis turbine design with hybrid method yielded a ratio of turbine height to radius (H/R) about 3.0 for reliable maximum power output.« less

  4. From monsoon to marine productivity in the Arabian Sea: insights from glacial and interglacial climates

    NASA Astrophysics Data System (ADS)

    Le Mézo, Priscilla; Beaufort, Luc; Bopp, Laurent; Braconnot, Pascale; Kageyama, Masa

    2017-07-01

    The current-climate Indian monsoon is known to boost biological productivity in the Arabian Sea. This paradigm has been extensively used to reconstruct past monsoon variability from palaeo-proxies indicative of changes in surface productivity. Here, we test this paradigm by simulating changes in marine primary productivity for eight contrasted climates from the last glacial-interglacial cycle. We show that there is no straightforward correlation between boreal summer productivity of the Arabian Sea and summer monsoon strength across the different simulated climates. Locally, productivity is fuelled by nutrient supply driven by Ekman dynamics. Upward transport of nutrients is modulated by a combination of alongshore wind stress intensity, which drives coastal upwelling, and by a positive wind stress curl to the west of the jet axis resulting in upward Ekman pumping. To the east of the jet axis there is however a strong downward Ekman pumping due to a negative wind stress curl. Consequently, changes in coastal alongshore stress and/or curl depend on both the jet intensity and position. The jet position is constrained by the Indian summer monsoon pattern, which in turn is influenced by the astronomical parameters and the ice sheet cover. The astronomical parameters are indeed shown to impact wind stress intensity in the Arabian Sea through large-scale changes in the meridional gradient of upper-tropospheric temperature. However, both the astronomical parameters and the ice sheets affect the pattern of wind stress curl through the position of the sea level depression barycentre over the monsoon region (20-150° W, 30° S-60° N). The combined changes in monsoon intensity and pattern lead to some higher glacial productivity during the summer season, in agreement with some palaeo-productivity reconstructions.

  5. The effect of active control on the performance and wake characteristics of an axial-flow Marine Hydrokinetic turbine

    NASA Astrophysics Data System (ADS)

    Hill, Craig; Vanness, Katherine; Stewart, Andy; Polagye, Brian; Aliseda, Alberto

    2016-11-01

    Turbulence-induced unsteady forcing on turbines extracting power from river, tidal, or ocean currents will affect performance, wake characteristics, and structural integrity. A laboratory-scale axial-flow turbine, 0 . 45 m in diameter, incorporating rotor speed sensing and independent blade pitch control has been designed and tested with the goal of increasing efficiency and/or decreasing structural loading. Laboratory experiments were completed in a 1 m wide, 0.75 m deep open-channel flume at moderate Reynolds number (Rec =6104 -2105) and turbulence intensity (T . I . = 2 - 10 %). A load cell connecting the hub to the shaft provided instantaneous forces and moments on the device, quantifying turbine performance under unsteady inflow and for different controls. To mitigate loads, blade pitch angles were controlled via individual stepper motors, while a six-axis load cell mounted at the root of one blade measured instantaneous blade forces and moments, providing insights into variable loading due to turbulent inflow and blade-tower interactions. Wake characteristics with active pitch control were compared to fixed blade pitch and rotor speed operation. Results are discussed in the context of optimization of design for axial-flow Marine Hydrokinetic turbines.

  6. Cavitation Characteristics of a NACA 63-424 Hydrofoil and Performance Comparison with a Bidirectional Version of the Foil

    NASA Astrophysics Data System (ADS)

    Nedyalkov, Ivaylo; Wosnik, Martin

    2012-11-01

    A NACA 63-424 hydrofoil with a 75 mm chord and a 152 mm span was tested in the recently renovated 6-inch high-speed water tunnel at the University of New Hampshire. The NACA 63-424 foil is being considered for use on rotors of marine hydrokinetic turbines, including the US Department of Energy Reference Horizontal Axis Turbine (RHAT) for tidal and ocean current applications. For various angles of attack, the foil was tested at speeds ranging from 2 m/s to 12 m/s. Pressure in the test section was varied independently. For each angle, speed and pressure setting, high speed videos were recorded (at 3600 frames per second and above). Cavitation inception and desinance were obtained. Lift and drag were measured using a new 2-component force balance. In tidal turbines applications, bidirectional foils do not require pitch control, hence the experiments were repeated for a bidirectional version of the NACA 63-424 foil and the characteristics of the two foils were compared. The results can be used to predict cavitation inception and performance of marine hydrokinetic turbines, for a given site, deployment depth and and tip speed ratio.

  7. Science aspects of 1980 ballistic missions to comet Encke, using Mariner and Pioneer spacecraft

    NASA Technical Reports Server (NTRS)

    Jaffe, L. D.; Elachi, C.; Giffin, C. E.; Huntress, W.; Newburn, R. L., Jr.; Parker, R. H.; Taylor, F. W.; Thorpe, T. E.

    1976-01-01

    Science aspects of a 1980 spacecraft reconnaissance of Comet Encke are considered. The mission discussed is a ballistic flyby (more exactly, a fly-through) of P/Encke, using either a spin stabilized spacecraft, without despin of instruments, or a 3-axis stabilized spacecraft.

  8. Surface response of blind thrust shown from high resolution topographic data and updated geochronology at Wheeler Ridge, CA

    NASA Astrophysics Data System (ADS)

    Kleber, E.; Arrowsmith, R.; DeVecchio, D. E.; Johnstone, S. A.; Rittenour, T. M.

    2015-12-01

    Wheeler Ridge is an asymmetric east-propagating anticline (10km axis, 330m relief) above a north-vergent blind thrust deforming Quaternary alluvial fan and shallow marine rocks at the northern front of the Transverse Ranges, San Joaquin Valley, CA. This area was a research foci in the 1990's when the soils, u-series soil carbonate dating, and subsurface structure of deformed strata identified from oil wells were used to create a kinematic model of deformation, and estimates of fault slip, uplift, and lateral propagation rates. A recent collection of light detection and ranging (lidar) topographic data and optically stimulated luminescence (OSL) data allow us to complete meter scale topographic analyses of the fluvial networks and hillslopes and correlate geomorphic response to tectonics. We interpret these results using a detailed morphological map and observe drainage network and hillslope process transitions both along and across the fold axis. With lidar topography, we extract common morphometrics (e.g., channel steepness-- ksn, eroded volume, hillslope relief) to illustrate how the landscape is responding to variations in uplift rate along the fold axis and show asymmetry of surface response on the forelimb and backlimb. The forelimb is dominated by large drainages with landslides initiating in the marine units at the core of the fold. Our topographic analysis shows that the stream channel indices values on the forelimb increase along the fold axis, away from the propagation tip. The backlimb drainages are dominantly long and linear with broad ridgelines. Using lidar and fieldwork, we see that uplifted backlimb surfaces preserve the deformed fan surface. The preliminary OSL results from alluvial fan units improve age control of previously defined surfaces, refining our understanding of the deposition and uplift of alluvial fan units on preserved on backlimb.

  9. Predicting Cavitation on Marine and Hydrokinetic Turbine Blades with AeroDyn V15.04

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

    Murray, Robynne

    Cavitation is an important consideration in the design of marine and hydrokinetic (MHK) turbines. The National Renewable Energy Laboratory's AeroDyn performance code was originally developed for horizontal-axis wind turbines and did not have the capability to predict cavitation inception. Therefore, AeroDyn has been updated to include the ability to predict cavitation on MHK turbines based on user-specified vapor pressure and submerged depth. This report outlines a verification of the AeroDyn V15.04 performance code for MHK turbines through a comparison to publicly available performance data.

  10. A Jupiter Orbiter mother/daughter spacecraft concept

    NASA Technical Reports Server (NTRS)

    Duxbury, J. H.

    1975-01-01

    The feasibility of a tandem launch of a mother/daughter spacecraft pair with a single launch vehicle for a 1981 Mariner Jupiter Orbiter mission is described. The mother is a close derivative of the three-axis stabilized Mariner Jupiter Saturn 1977 spacecraft with the addition of a Viking-type propulsion module for orbit capture; it concentrates on the planetology and satellite science objectives. The daughter is a small, simple spin-stabilized spacecraft taking advantage of the mother's transit and delivery capabilities; it obtains in-situ measurements of the surrounding planetary environment. A conceptual design of the daughter spacecraft is presented.

  11. Comparison of current meters used for stream gaging

    USGS Publications Warehouse

    Fulford, Janice M.; Thibodeaux, Kirk G.; Kaehrle, William R.

    1994-01-01

    The U.S. Geological Survey (USGS) is field and laboratory testing the performance of several current meters used throughout the world for stream gaging. Meters tested include horizontal-axis current meters from Germany, the United Kingdom, and the People's Republic of China, and vertical-axis and electromagnetic current meters from the United States. Summarized are laboratory test results for meter repeatability, linearity, and response to oblique flow angles and preliminary field testing results. All current meters tested were found to under- and over-register velocities; errors usually increased as the velocity and angle of the flow increased. Repeatability and linearity of all meters tested were good. In the field tests, horizontal-axis meters, except for the two meters from the People's Republic of China, registered higher velocity than did the vertical-axis meters.

  12. Marine Magnetic Anomalies and the Reconstruction of the World

    NASA Technical Reports Server (NTRS)

    Heirtzler, James R.; Smith, David E. (Technical Monitor)

    2000-01-01

    Until the middle of the 20th century little was known about magnetic anomalies in the oceans. Then it was discovered that there are relatively large anomalies in most of the oceans and they were unrelated to any geological structure known at that time. In the early 1950's large anomalies had been found over the Mid-Atlantic Ridge, and linear anomalies over the eastern continental shelf of North America and, shortly after that, off the west coast. A survey of the ridge south of Iceland showed that the anomalies were linear, parallel to the ridge axis, and symmetrical about the axis. Using the theory that the anomalies were caused by geomagnetic field reversals and seafloor spreading it was possible to greatly extend the time scale of geomagnetic reversals, to determine the velocity of seafloor spreading and estimate the time of opening of the North Atlantic. Lamont had a world-wide collection of marine magnetic profiles. These were used, systematically, to determine the positions of most of the land masses of the world since the beginnings of the world's present oceans.

  13. Compact, Lightweight Electromagnetic Pump for Liquid Metal

    NASA Technical Reports Server (NTRS)

    Godfroy, Thomas; Palzin, Kurt

    2010-01-01

    A proposed direct-current electromagnetic pump for circulating a molten alkali metal alloy would be smaller and lighter and would demand less input power, relative to currently available pumps of this type. (Molten alkali metals are used as heat-transfer fluids in high-temperature stages of some nuclear reactors.) The principle of operation of this or any such pump involves exploitation of the electrical conductivity of the molten metal: An electric current is made to pass through the liquid metal along an axis perpendicular to the longitudinal axis of the flow channel, and a magnetic field perpendicular to both the longitudinal axis and the electric current is superimposed on the flowchannel region containing the electric current. The interaction between the electric current and the magnetic field produces the pumping force along the longitudinal axis. The advantages of the proposed pump over other such pumps would accrue from design features that address overlapping thermal and magnetic issues.

  14. Repeatability and oblique flow response characteristics of current meters

    USGS Publications Warehouse

    Fulford, Janice M.; Thibodeaux, Kirk G.; Kaehrle, William R.; ,

    1993-01-01

    Laboratory investigation into the precision and accuracy of various mechanical-current meters are presented. Horizontal-axis and vertical-axis meters that are used for the measurement of point velocities in streams and rivers were tested. Meters were tested for repeatability and response to oblique flows. Both horizontal- and vertical-axis meters were found to under- and over-register oblique flows with errors generally increasing as the velocity and angle of flow increased. For the oblique flow tests, magnitude of errors were smallest for horizontal-axis meters. Repeatability of all meters tested was good, with the horizontal- and vertical-axis meters performing similarly.

  15. Flow structure in the near wake of a horizontal axis marine current turbine under steady and unsteady inflow conditions

    NASA Astrophysics Data System (ADS)

    Luznik, Luksa; Lust, Ethan; Flack, Karen

    2015-11-01

    Near wake flow field results are presented for a 1/25 scale, 0.8 m diameter (D) two bladed horizontal axis tidal turbine. The 2D PIV measurements were obtained in the USNA 380 ft tow tank for two inflow conditions. The first case had steady inflow conditions, i.e. the turbine was towed at a constant carriage speed (Utow = 1.68 m/s) and the second case had a constant carriage speed and incoming regular waves with a period of 2.3 seconds and 0.18 m wave height. The underwater PIV system is comprised of two submersible housings with forward looking submersible containing laser sheet forming optics, and the side looking submersible includes a camera and remote focus/aperture electronics. The resulting individual field of view for this experiment was nominally 30x30 cm2. Near wake mapping is accomplished by ``tiling'' individual fields of view with approximately 5 cm overlap. All measurements were performed at the nominal tip speed ratio (TSR) of 7. The mapping is accomplished in a vertical streamwise plane (x-z plane) centered on the turbine nacelle and the image pair captures were phase locked to two phases: reference blade horizontal and reference blade vertical. Results presented include distribution of mean velocities, Reynolds stresses, 2D turbulent kinetic energy. The discussion will focus on comparisons between steady and unsteady case. Further discussion will include comparisons between the current high resolution PIV measurements and the previous point measurements with the same turbine at different lateral planes in the same flow conditions.

  16. A Numerical Model of Seawater Volume and Velocity Dynamic for Marine Currents Power Plant in the Bangka Strait, North Sulawesi, Indonesia

    NASA Astrophysics Data System (ADS)

    Rompas, P. T. D.; Taunaumang, H.; Sangari, F. J.

    2017-03-01

    One of equipment as prime movers in the marine current power plant is turbine. Marine current turbines require a data of marine currents velocity in its design. The objective of this study was to get the velocities distribution of marine currents in the Bangka strait. The method used survey, observation, and measurement in the Bangka strait. The data of seawater density conducted measurement in the Bangka strait. The data of width and depth of the strait collected from the map of Bangka strait and its depth of the sea. Problem solving of the study used a numerical model. The velocities distribution of marine current obtained from a numerical model in the form of numerical program. The results showed that the velocities distribution at seawater column when low and high tide currents which the maximum happened at 0.1 Sv were 0-0.9 and 0-1.0 m/s respectively, while at 0.3 Sv were 0-2.7 and 0-3.0 m/s respectively. The results will be a product in analyzing the potential kinetic energy that used to design profile of the turbines as prime mover for marine currents power plant in the Bangka strait, North Sulawesi, Indonesia.

  17. Performance and Near-Wake Flow field of A Marine Hydrokinetic Turbine Operating in Free surface Proximity

    NASA Astrophysics Data System (ADS)

    Banerjee, Arindam; Kolekar, Nitin

    2015-11-01

    The current experimental investigation aims at understanding the effect of free surface proximity and associated blockage on near-wake flow-field and performance of a three bladed horizontal axis marine hydrokinetic turbine. Experiments were conducted on a 0.14m radius, three bladed constant chord turbine in a 0.61m ×0.61m test section water channel. The turbine was subjected to various rotational speeds, flow speeds and depths of immersion. Experimental data was acquired through a submerged in-line thrust-torque sensor that was corrected to an unblocked dataset with a blockage correction using measured thrust data. A detailed comparison is presented between blocked and unblocked datasets to identify influence of Reynolds number and free surface proximity on blockage effects. The percent change in Cp was found to be dependent on flow velocity, rotational speed and free surface to blade tip clearance. Further, flow visualization using a stereoscopic particle image velocimetry was carried out in the near-wake region of turbine to understand the mechanism responsible for variation of Cp with rotational speed and free surface proximity. Results revealed presence of slower wake at higher rotational velocities and increased asymmetry in the wake at high free surface proximity.

  18. Environmental Data Collection Using Autonomous Wave Gliders

    DTIC Science & Technology

    2014-12-01

    Observing System IMU Inertial Measurement Unit LRI Liquid Robotics, Inc. MASFlux Marine-Air-Sea-Flux METOC meteorological and oceanographic...position, velocity, heading, pitch, roll , and six-axis acceleration rates (Figure 11). A separate temperature probe also provides sea surface...Position, Velocity, and Magnetic declination True North Revolution Technologies GS Gyro Stabilized Electronic Compass Heading, Pitch, and Roll

  19. A polar-region-adaptable systematic bias collaborative measurement method for shipboard redundant rotational inertial navigation systems

    NASA Astrophysics Data System (ADS)

    Wang, Lin; Wu, Wenqi; Wei, Guo; Lian, Junxiang; Yu, Ruihang

    2018-05-01

    The shipboard redundant rotational inertial navigation system (RINS) configuration, including a dual-axis RINS and a single-axis RINS, can satisfy the demand of marine INSs of especially high reliability as well as achieving trade-off between position accuracy and cost. Generally, the dual-axis RINS is the master INS, and the single-axis RINS is the hot backup INS for high reliability purposes. An integrity monitoring system performs a fault detection function to ensure sailing safety. However, improving the accuracy of the backup INS in case of master INS failure has not been given enough attention. Without the aid of any external information, a systematic bias collaborative measurement method based on an augmented Kalman filter is proposed for the redundant RINSs. Estimates of inertial sensor biases can be used by the built-in integrity monitoring system to monitor the RINS running condition. On the other hand, a position error prediction model is designed for the single-axis RINS to estimate the systematic error caused by its azimuth gyro bias. After position error compensation, the position information provided by the single-axis RINS still remains highly accurate, even if the integrity monitoring system detects a dual-axis RINS fault. Moreover, use of a grid frame as a navigation frame makes the proposed method applicable in any area, including the polar regions. Semi-physical simulation and experiments including sea trials verify the validity of the method.

  20. 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

  1. The normalization of solar X-ray data from many experiments.

    NASA Technical Reports Server (NTRS)

    Wende, C. D.

    1972-01-01

    A conversion factor is used to convert Geiger (GM) tube count rates or ion chamber currents into units of the incident X-ray energy flux in a specified passband. A method is described which varies the passband to optimize these conversion factors such that they are relatively independent of the spectrum of the incident photons. This method was applied to GM tubes flown on Explorers 33 and 35 and Mariner 5 and to ion chambers flown on OSO 3 and OGO 4. Revised conversion factors and passbands are presented, and the resulting absolute solar X-ray fluxes based on these are shown to improve the agreement between the various experiments. Calculations have shown that, although the GM tubes on Explorer 33 viewed the Sun off-axis, the effective passband did not change appreciably, and the simple normalization of the count rates to the count rates of a similar GM tube on Explorer 35 was justified.

  2. The influence of surface waves on tidal turbine performance characteristics

    NASA Astrophysics Data System (ADS)

    Van Benthem, M.; Luznik, L.; Flack, K.; Lust, E.

    2012-12-01

    Performance characteristics are presented for a 1/25th scale horizontal axis marine current turbine operating in calm conditions and in the presence of intermediate and deep water waves. The two-bladed turbine has radius of 0.4 m and a maximum blade pitch of 17°. The hydrofoil is a NACA63-618 which was selected to be Reynolds number independent in the operational range (ReC = 2 - 4 x 105). The experiments were performed in the 116 m towing tank at the United States Naval Academy at two depths 0.8D and 1.6D measured from the blade tip to the mean free surface. The performance characteristics without waves match expected results from blade-element-momentum theory. Results show that the average power coefficient is unaffected by the presence of waves, however, the phase averaged results indicate significant variation with wave phase.

  3. Divergences between clinical and research methods for assessing personality disorders: implications for research and the evolution of axis II.

    PubMed

    Westen, D

    1997-07-01

    The purpose of this study was to examine the extent to which instruments for assessing axis II diverge from clinical diagnostic processes. Subjects in the first study were 52 clinicians with experience in assessment and treatment of patients with personality disorders, who were surveyed about the methods they use in clinical practice to make diagnoses and other aspects of the diagnostic process. A second study replicated the major findings with a random national sample of 1,901 experienced psychiatrists and psychologists. Whereas current instruments rely primarily on direct questions derived from DSM-IV, clinicians of every theoretical persuasion found direct questions useful for assessing axis I disorders but only marginally so for axis II. They made axis II diagnoses, instead, by listening to patients describe interpersonal interactions and observing their behavior with the interviewer. In contrast to findings with current research instruments, most patients with personality disorders in clinical practice receive only one axis II diagnosis, and if they receive more than one, one is considered primary. Clinicians reported treating a substantial number of patients for enduring personality patterns that current axis II instruments do not assess, many of which meet neither axis I nor axis II criteria, notably problems with relatedness, work, self-esteem, and chronic subclinical depressive traits. Measurements of axis II were constructed by using a model derived from axis I instruments that diverges from clinical diagnostic procedures in a way that may be problematic for the assessment of personality disorders and the development of a more clinically and empirically sound taxonomy.

  4. Constraining the Spatial Extent of Marine Oil Snow Sedimentation and Flocculent Accumulation Following the Deepwater Horizon Event Using an Excess 210Pb Flux Approach.

    PubMed

    Schwing, P T; Brooks, G R; Larson, R A; Holmes, C W; O'Malley, B J; Hollander, D J

    2017-06-06

    Following the Deepwater Horizon (DWH) event in 2010, there were several lines of evidence indicating the presence of marine oil snow sedimentation and flocculent accumulation (MOSSFA). A significant amount of marine oil snow formed in the water column of the northern Gulf of Mexico (nGoM), settled rapidly, and ultimately accumulated in the sediments of the nGoM. This study utilized a commonly used radioisotope tracer (excess 210 Pb, 210 Pb xs ) from 32 sediment cores collected from 2010 to 2013 to characterize the spatial extent of MOSSFA on the seafloor. Relative to pre-DWH conditions, an increase in 210 Pb xs flux occurred in two distinct regions: (1) in the western portion of the study area on an east-northeast to west-southwest axis, stretching 230 km southwest and 140 km northeast of the DWH wellhead, and (2) in the eastern portion of the study area on a 70 km northeast to southwest axis near the DeSoto Canyon. The total sedimentary spatial extent of MOSSFA, as calculated by increased 210 Pb xs flux after 2010, ranged from 12 805 to 35 425 km 2 . 210 Pb xs flux provides a valuable tool for documenting the spatial extent of MOSSFA following DWH and will continue to aid in the determination of advective transport and ultimate depocenters of MOSSFA material.

  5. Influence of marine current on vertical migration of Pb in marine bay

    NASA Astrophysics Data System (ADS)

    Yu, Chen; Hong, Ai; Danfeng, Yang; Huijuan, Zhao; Dongfang, Yang

    2018-02-01

    This paper analyzed that vertical migration of Pb contents waters in Jiaozhou Bay, and revealed the influence of marine current on vertical migration process. Results showed that Pb contents in bottom waters of Jiaozhou Bay in April and July 1988 were 1.49-18.53 μg L-1 and 12.68/-27.64 μg L-1, respectively. The pollution level of Pb in bottom waters was moderate to heavy, and were showing temporal variations and spatial heterogeneity. The vertical migration process of Pb in April 1988 included a drifting process from the southwest to the north by means of the marine current was rapid in this region. The vertical migration process of Pb in July 1988 in the open waters included no drifting process since the flow rate of marine current was relative low in this region. The vertical migration process of Pb was jointly determined by vertical water’s effect, source input and water exchange, and the influence of marine current on the vertical migration of Pb in marine bay was significant.

  6. Off-axis current drive and real-time control of current profile in JT-60U

    NASA Astrophysics Data System (ADS)

    Suzuki, T.; Ide, S.; Oikawa, T.; Fujita, T.; Ishikawa, M.; Seki, M.; Matsunaga, G.; Hatae, T.; Naito, O.; Hamamatsu, K.; Sueoka, M.; Hosoyama, H.; Nakazato, M.; JT-60 Team

    2008-04-01

    Aiming at optimization of current profile in high-β plasmas for higher confinement and stability, a real-time control system of the minimum of the safety factor (qmin) using the off-axis current drive has been developed. The off-axis current drive can raise the safety factor in the centre and help to avoid instability that limits the performance of the plasma. The system controls the injection power of lower-hybrid waves, and hence its off-axis driven current in order to control qmin. The real-time control of qmin is demonstrated in a high-β plasma, where qmin follows the temporally changing reference qmin,ref from 1.3 to 1.7. Applying the control to another high-β discharge (βN = 1.7, βp = 1.5) with m/n = 2/1 neo-classical tearing mode (NTM), qmin was raised above 2 and the NTM was suppressed. The stored energy increased by 16% with the NTM suppressed, since the resonant rational surface was eliminated. For the future use for current profile control, current density profile for off-axis neutral beam current drive (NBCD) is for the first time measured, using the motional Stark effect diagnostic. Spatially localized NBCD profile was clearly observed at the normalized minor radius ρ of about 0.6-0.8. The location was also confirmed by multi-chordal neutron emission profile measurement. The total amount of the measured beam driven current was consistent with the theoretical calculation using the ACCOME code. The CD location in the calculation was inward shifted than the measurement.

  7. Flat-topped beam transmittance in anisotropic non-Kolmogorov turbulent marine atmosphere

    NASA Astrophysics Data System (ADS)

    Ata, Yalçın; Baykal, Yahya

    2017-10-01

    Turbulence affects optical propagation, and, as a result, the intensity is attenuated along the path of propagation. The attenuation becomes significant when the turbulence becomes stronger. Transmittance is a measure indicating how much power is collected at the receiver after the optical wave propagates in the turbulent medium. The on-axis transmittance is formulated when a flat-topped optical beam propagates in a marine atmosphere experiencing anisotropic non-Kolmogorov turbulence. Variations in the transmittance are evaluated versus the beam source size, beam number, link distance, power law exponent, anisotropy factor, and structure constant. It is found that larger beam source sizes and beam numbers yield higher transmittance values; however, as the link distance, power law exponent, anisotropy factor, or structure constant increase, transmittance values are lowered. Our results will help in the performance evaluations of optical wireless communication and optical imaging systems operating in a marine atmosphere.

  8. Mariner 6 and 7 picture analysis

    NASA Technical Reports Server (NTRS)

    Leighton, R. B.

    1975-01-01

    Analysis of Mariner 6 and 7 far-encounter (FE) pictures is discussed. The purpose of the studies was to devise ways to combine digital data from the full set of FE pictures so as to improve surface resolution, distinguish clouds and haze patches from permanent surface topographic markings, deduce improved values for radius, oblateness, and spin-axis orientation, and produce a composite photographic map of Mars. Attempts to measure and correct camera distortions, locate each image in the frame, and convert image coordinates to martian surface coordinates were highly successful; residual uncertainties in location were considerably less than one pixel. However, analysis of the data to improve the radius, figure, and axial tilt and to produce a composite map was curtailed because of the superior data provided by Mariner 9. The data, programs, and intermediate results are still available (1976), and the project could be resumed with little difficulty.

  9. The magnetic orientation of the Antarctic amphipod Gondogeneia antarctica is cancelled by very weak radiofrequency fields.

    PubMed

    Tomanova, K; Vacha, M

    2016-06-01

    Studies on weak man-made radiofrequency (RF) electromagnetic fields affecting animal magnetoreception aim for a better understanding of the reception mechanism and also point to a new phenomenon having possible consequences in ecology and environmental protection. RF impacts on magnetic compasses have recently been demonstrated in migratory birds and other vertebrates. We set out to investigate the effect of RF on the magnetic orientation of the Antarctic krill species Gondogeneia antarctica, a small marine crustacean widespread along the Antarctic littoral line. Here, we show that upon release, G. antarctica (held under laboratory conditions) escaped in the magnetically seaward direction along the magnetic sea-land axis (y-axis) of the home beach. However, the animals were disoriented after being exposed to RF. Orientation was lost not only in an RF field with a magnetic flux density of 20 nT, as expected according to the literature, but even under the 2 nT originally intended as a control. Our results extend recent findings of the extraordinary sensitivity of animal magnetoreception to weak RF fields in marine invertebrates. © 2016. Published by The Company of Biologists Ltd.

  10. Pleading for the use of biodegradable polymers in favor of marine environments and to avoid an asbestos-like problem for the future.

    PubMed

    Kubota, Masahisa; Takayama, Katsumi; Namimoto, Daisuke

    2005-06-01

    Research results about the movement and accumulation of floating marine debris drifting throughout the world's oceans are reviewed in this paper. A mechanism for this accumulation and movement is strongly associated with surface currents consisting of the Ekman drift and the geostrophic current, because all floating marine debris is passive to surface currents. The basic published mechanism for the North Pacific is common across the world's ocean. After marine debris accumulates in the narrow Ekman convergence zone, it is moved to the east by geostrophic currents. The most important thing is that floating marine debris concentrates in some specific regions, independent of the initial quantity of marine debris. In order to resolve this problem and to avoid an asbestos-like problem, the use of biodegradable polymers is important in our daily life.

  11. Attenuation and image noise level based online z-axis tube current modulation for CT scans independent with localizer radiograph: simulation study and results

    NASA Astrophysics Data System (ADS)

    Tian, Yi; Chen, Mahao; Kong, Jun

    2009-02-01

    With the online z-axis tube current modulation (OZTCM) technique proposed by this work, full automatic exposure control (AEC) for CT systems could be realized with online feedback not only for angular tube current modulation (TCM) but also for z-axis TCM either. Then the localizer radiograph was not required for TCM any more. OZTCM could be implemented with 2 schemes as attenuation based μ-OZTCM and image noise level based μ-OZTCM. Respectively the maximum attenuation of projection readings and standard deviation of reconstructed images can be used to modulate the tube current level in z-axis adaptively for each half (180 degree) or full (360 degree) rotation. Simulation results showed that OZTCM achieved better noise level than constant tube current scan case by using same total dose in mAs. The OZTCM can provide optimized base tube current level for angular TCM to realize an effective auto exposure control when localizer radiograph is not available or need to be skipped for simplified scan protocol in case of emergency procedure or children scan, etc.

  12. Sensor Buoy System for Monitoring Renewable Marine Energy Resources.

    PubMed

    García, Emilio; Quiles, Eduardo; Correcher, Antonio; Morant, Francisco

    2018-03-22

    In this paper we present a multi-sensor floating system designed to monitor marine energy parameters, in order to sample wind, wave, and marine current energy resources. For this purpose, a set of dedicated sensors to measure the height and period of the waves, wind, and marine current intensity and direction have been selected and installed in the system. The floating device incorporates wind and marine current turbines for renewable energy self-consumption and to carry out complementary studies on the stability of such a system. The feasibility, safety, sensor communications, and buoy stability of the floating device have been successfully checked in real operating conditions.

  13. Sensor Buoy System for Monitoring Renewable Marine Energy Resources

    PubMed Central

    García, Emilio; Morant, Francisco

    2018-01-01

    In this paper we present a multi-sensor floating system designed to monitor marine energy parameters, in order to sample wind, wave, and marine current energy resources. For this purpose, a set of dedicated sensors to measure the height and period of the waves, wind, and marine current intensity and direction have been selected and installed in the system. The floating device incorporates wind and marine current turbines for renewable energy self-consumption and to carry out complementary studies on the stability of such a system. The feasibility, safety, sensor communications, and buoy stability of the floating device have been successfully checked in real operating conditions. PMID:29565823

  14. The stability of steady motion of magnetic domain wall: Role of higher-order spin-orbit torques

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

    He, Peng-Bin, E-mail: hepengbin@hnu.edu.cn; Yan, Han; Cai, Meng-Qiu

    The steady motion of magnetic domain wall driven by spin-orbit torques is investigated analytically in the heavy/ferromagnetic metal nanowires for three cases with a current transverse to the in-plane and perpendicular easy axis, and along the in-plane easy axis. By the stability analysis of Walker wall profile, we find that if including the higher-order spin-orbit torques, the Walker breakdown can be avoided in some parameter regions of spin-orbit torques with a current transverse to or along the in-plane easy axis. However, in the case of perpendicular anisotropy, even considering the higher-order spin-orbit torques, the velocity of domain wall cannot bemore » efficiently enhanced by the current. Furthermore, the direction of wall motion is dependent on the configuration and chirality of domain wall with a current along the in-plane easy axis or transverse to the perpendicular one. Especially, the direction of motion can be controlled by the initial chirality of domain wall. So, if only involving the spin-orbit mechanism, it is preferable to adopt the scheme of a current along the in-plane easy axis for enhancing the velocity and controlling the direction of domain wall.« less

  15. Enhanced spin transfer torque effect for transverse domain walls in cylindrical nanowires

    NASA Astrophysics Data System (ADS)

    Franchin, Matteo; Knittel, Andreas; Albert, Maximilian; Chernyshenko, Dmitri S.; Fischbacher, Thomas; Prabhakar, Anil; Fangohr, Hans

    2011-09-01

    Recent studies have predicted extraordinary properties for transverse domain walls in cylindrical nanowires: zero depinning current, the absence of the Walker breakdown, and applications as domain wall oscillators. In order to reliably control the domain wall motion, it is important to understand how they interact with pinning centers, which may be engineered, for example, through modulations in the nanowire geometry (such as notches or extrusions) or in the magnetic properties of the material. In this paper we study the motion and depinning of transverse domain walls through pinning centers in ferromagnetic cylindrical nanowires. We use (i) magnetic fields and (ii) spin-polarized currents to drive the domain walls along the wire. The pinning centers are modelled as a section of the nanowire which exhibits a uniaxial crystal anisotropy where the anisotropy easy axis and the wire axis enclose a variable angle θP. Using (i) magnetic fields, we find that the minimum and the maximum fields required to push the domain wall through the pinning center differ by 30%. On the contrary, using (ii) spin-polarized currents, we find variations of a factor 130 between the minimum value of the depinning current density (observed for θP=0∘, i.e., anisotropy axis pointing parallel to the wire axis) and the maximum value (for θP=90∘, i.e., anisotropy axis perpendicular to the wire axis). We study the depinning current density as a function of the height of the energy barrier of the pinning center using numerical and analytical methods. We find that for an industry standard energy barrier of 40kBT, a depinning current of about 5μA (corresponding to a current density of 6×1010A/m2 in a nanowire of 10nm diameter) is sufficient to depin the domain wall. We reveal and explain the mechanism that leads to these unusually low depinning currents. One requirement for this depinning mechanism is for the domain wall to be able to rotate around its own axis. With the right barrier design, the spin torque transfer term is acting exactly against the damping in the micromagnetic system, and thus the low current density is sufficient to accumulate enough energy quickly. These key insights may be crucial in furthering the development of novel memory technologies, such as the racetrack memory, that can be controlled through low current densities.

  16. Muscle transcriptome response to ACTH administration in a free-ranging marine mammal

    PubMed Central

    Champagne, Cory D.; Preeyanon, Likit; Ortiz, Rudy M.; Crocker, Daniel E.

    2015-01-01

    While much of our understanding of stress physiology is derived from biomedical studies, little is known about the downstream molecular consequences of adaptive stress responses in free-living animals. We examined molecular effectors of the stress hormones cortisol and aldosterone in the northern elephant seal, a free-ranging study system in which extreme physiological challenges and cortisol fluctuations are a routine part of life history. We stimulated the neuroendocrine stress axis by administering exogenous adrenocorticotropic hormone (ACTH) and examined the resultant effects by measuring corticosteroid hormones, metabolites, and gene expression before, during, and following administration. ACTH induced an elevation in cortisol, aldosterone, glucose, and fatty acids within 2 h, with complete recovery observed within 24 h of administration. The global transcriptional response of elephant seal muscle tissue to ACTH was evaluated by transcriptomics and involved upregulation of a highly coordinated network of conserved glucocorticoid (GC) target genes predicted to promote metabolic substrate availability without causing deleterious effects seen in laboratory animals. Transcriptional recovery from ACTH was characterized by downregulation of GC target genes and restoration of cell proliferation, metabolism, and tissue maintenance pathways within 24 h. Differentially expressed genes included several adipokines not previously described in muscle, reflecting unique metabolic physiology in fasting-adapted animals. This study represents one of the first transcriptome analyses of cellular responses to hypothalamic-pituitary-adrenal axis stimulation in a free-living marine mammal and suggests that compensatory, tissue-sparing mechanisms may enable marine mammals to maintain cortisol and aldosterone sensitivity while avoiding deleterious long-term consequences of stress. PMID:26038394

  17. Autonomous & Adaptive Oceanographic Feature Tracking on Board Autonomous Underwater Vehicles

    DTIC Science & Technology

    2015-02-01

    44 3.6 Tracking the Marine ermocline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 3.6.1 ermocline Definition ...intelligent autonomy algorithms to adapt the vehicle’s motion to changes in the environment, effectively seeking out and tracking an oceanographic...interface, H is the mean water depth, and f is the Coriolis parameter (twice the earth’s angular velocity about its vertical axis) [38]. at is, the

  18. The Bottlenose Dolphin (Tursiops truncatus) as a Model to Understand Variation in Stress and Reproductive Hormone Measures in Relation to Sampling Matrix, Demographics, and Environmental Factors

    DTIC Science & Technology

    2011-09-30

    support the existence of these same stress response pathways in marine mammals. While the HPA axis and physiological processes driven by the GCs are...cortisol, aldosterone , thyroid and reproductive hormones) have been routinely measured in blood as part of the health assessment which also includes a

  19. The Management of New Ideas: An Entrepreneur’s Perspective

    DTIC Science & Technology

    2017-06-01

    MARCIMS Marine Civil Information Management System MARCORSYSCOM Marine Corps Systems Command MARFORPAC Marine Forces Pacific Command MCCDC Marine Corp...any personally identifying information . While this work aims to generate theory related to the management of new ideas and their meanings during the...currently deployed civil information management system as the current system in use was antiquated and frustrating to use. While we were enthusiastic

  20. The role of a-axis grains in the transition to the normal state of YBa{sub 2}Cu{sub 3}O{sub 7−δ} films and of 2G-coated conductors when induced by high electrical current densities

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

    Bernstein, P., E-mail: pierre.bernstein@ensicaen.fr; Harnois, C.; Mc Loughlin, C.

    The influence of surface defects, in particular of a-axis grains, on the transition to the normal state induced by high current densities in YBa{sub 2}Cu{sub 3}O{sub 7−δ} (YBCO) thin films and in a commercial 2G-coated conductor is investigated. For that purpose, the surface of the samples is observed by scanning electron microscopy and isothermal current-voltage curves are measured at different temperatures with pulsed currents up to the quenching value I*. The results show that the ratio of I* to the critical current is large if a-axis grains are not visible at the surface of the YBCO films, while it ismore » much lower if the surface includes a-axis grains as this is the case for the coated conductor. The connection between the transition onset and the vortex dynamics, as well as the role of the a-axis grains in this process are discussed. The relation between the I* values obtained from thermal calculations and those resulting from vortex dynamics considerations is also discussed, as well as the possible consequences suggested by this work for the different applications of the coated conductors.« less

  1. Two-point motional Stark effect diagnostic for Madison Symmetric Torus

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

    Ko, J.; Den Hartog, D. J.; Caspary, K. J.

    2010-10-15

    A high-precision spectral motional Stark effect (MSE) diagnostic provides internal magnetic field measurements for Madison Symmetric Torus (MST) plasmas. Currently, MST uses two spatial views - on the magnetic axis and on the midminor (off-axis) radius, the latter added recently. A new analysis scheme has been developed to infer both the pitch angle and the magnitude of the magnetic field from MSE spectra. Systematic errors are reduced by using atomic data from atomic data and analysis structure in the fit. Reconstructed current density and safety factor profiles are more strongly and globally constrained with the addition of the off-axis radiusmore » measurement than with the on-axis one only.« less

  2. High Risk Behaviors in Marine Mammals: Linking Behavioral Responses to Anthropogenic Disturbance to Biological Consequences

    DTIC Science & Technology

    2014-09-30

    98) Prescribed by ANSI Std Z39-18 2 injury via cardiovascular performance during submergence. Neuro -protection through globin deposition and...relationships for stroking costs, aerobic dive limits, types of neuro -protection (globin deposition, capillarity), and cardiac risk factors that will be mapped...Greenland. A custom built ECG recorder with 3- axis accelerometer recorder and pressure transducer was combined with retrieval transmitters (Argos

  3. Simulating wind and marine hydrokinetic turbines with actuator lines in RANS and LES

    NASA Astrophysics Data System (ADS)

    Bachant, Peter; Wosnik, Martin

    2015-11-01

    As wind and marine hydrokinetic (MHK) turbine designs mature, focus is shifting towards improving turbine array layouts for maximizing overall power output, i.e., minimizing wake interference for axial-flow or horizontal-axis turbines, or taking advantage of constructive wake interaction for cross-flow or vertical-axis turbines. Towards this goal, an actuator line model (ALM) was developed to provide a computationally feasible method for simulating full turbine arrays inside Navier-Stokes models. The ALM predicts turbine loading with the blade element method combined with sub-models for dynamic stall and flow curvature. The open-source software is written as an extension library for the OpenFOAM CFD package, which allows the ALM body force to be applied to their standard RANS and LES solvers. Turbine forcing is also applied to volume of fluid (VOF) models, e.g., for predicting free surface effects on submerged MHK devices. An additional sub-model is considered for injecting turbulence model scalar quantities based on actuator line element loading. Results are presented for the simulation of performance and wake dynamics of axial- and cross-flow turbines and compared with moderate Reynolds number experiments and body-fitted mesh, blade-resolving CFD. Work supported by NSF-CBET grant 1150797.

  4. Summary of Research 1998, Department of Meteorology.

    DTIC Science & Technology

    1999-08-01

    Marine Education, Vol. 15, No. 3, p. 28,1998. Murphree, X, "Hot and Cold Glasses: Activities on the Global Water Cycle ," Current: The Journal of...Marine Education, Vol. 15, No. 3, p. 28,1998. Murphree, T, "Hot and Cold Glasses: Activities on the Global Water Cycle ," Current: The Journal of Marine

  5. Freshwater savings from marine protein consumption

    NASA Astrophysics Data System (ADS)

    Gephart, Jessica A.; Pace, Michael L.; D'Odorico, Paolo

    2014-01-01

    Marine fisheries provide an essential source of protein for many people around the world. Unlike alternative terrestrial sources of protein, marine fish production requires little to no freshwater inputs. Consuming marine fish protein instead of terrestrial protein therefore represents freshwater savings (equivalent to an avoided water cost) and contributes to a low water footprint diet. These water savings are realized by the producers of alternative protein sources, rather than the consumers of marine protein. This study quantifies freshwater savings from marine fish consumption around the world by estimating the water footprint of replacing marine fish with terrestrial protein based on current consumption patterns. An estimated 7 600 km3 yr-1 of water is used for human food production. Replacing marine protein with terrestrial protein would require an additional 350 km3 yr-1 of water, meaning that marine protein provides current water savings of 4.6%. The importance of these freshwater savings is highly uneven around the globe, with savings ranging from as little as 0 to as much as 50%. The largest savings as a per cent of current water footprints occur in Asia, Oceania, and several coastal African nations. The greatest national water savings from marine fish protein occur in Southeast Asia and the United States. As the human population increases, future water savings from marine fish consumption will be increasingly important to food and water security and depend on sustainable harvest of capture fisheries and low water footprint growth of marine aquaculture.

  6. Progress in the development of shallow-water mapping systems

    USGS Publications Warehouse

    Bergeron, E.; Worley, C.R.; O'Brien, T.

    2007-01-01

    The USGS (US Geological Survey) Coastal and Marine Geology has deployed an advance autonomous shallow-draft robotic vehicle, Iris, for shallow-water mapping in Apalachicola Bay, Florida. The vehicle incorporates a side scan sonar system, seismic-reflection profiler, single-beam echosounder, and global positioning system (GPS) navigation. It is equipped with an onboard microprocessor-based motor controller, delivering signals for speed and steering to hull-mounted brushless direct-current thrusters. An onboard motion sensor in the Sea Robotics vehicle control system enclosure has been integrated in the vehicle to measure the vehicle heave, pitch, roll, and heading. Three water-tight enclosures are mounted along the vehicle axis for the Edgetech computer and electronics system including the Sea Robotics computer, a control and wireless communications system, and a Thales ZXW real-time kinematic (RTK) GPS receiver. The vehicle has resulted in producing high-quality seismic reflection and side scan sonar data, which will help in developing the baseline oyster habitat maps.

  7. Offshore Hydrokinetic Energy Conversion for Onshore Power Generation

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.; Chao, Yi

    2009-01-01

    Design comparisons have been performed for a number of different tidal energy systems, including a fully submerged, horizontal-axis electro-turbine system, similar to Verdant Tidal Turbines in New York's East River, a platform-based Marine Current Turbine, now operating in Northern Ireland's Strangford Narrows, and the Rotech Lunar Energy system, to be installed off the South Korean Coast. A fourth type of tidal energy system studied is a novel JPL/Caltech hydraulic energy transfer system that uses submerged turbine blades which are mechanically attached to adjacent high-pressure pumps, instead of to adjacent electrical turbines. The generated highpressure water streams are combined and transferred to an onshore hydroelectric plant by means of a closed-cycle pipeline. The hydraulic energy transfer system was found to be cost competitive, and it allows all electronics to be placed onshore, thus greatly reducing maintenance costs and corrosion problems. It also eliminates the expenses of conditioning and transferring multiple offshore power lines and of building offshore platforms embedded in the sea floor.

  8. Coordinated Control of Cross-Flow Turbines

    NASA Astrophysics Data System (ADS)

    Strom, Benjamin; Brunton, Steven; Polagye, Brian

    2016-11-01

    Cross-flow turbines, also known as vertical-axis turbines, have several advantages over axial-flow turbines for a number of applications including urban wind power, high-density arrays, and marine or fluvial currents. By controlling the angular velocity applied to the turbine as a function of angular blade position, we have demonstrated a 79 percent increase in cross-flow turbine efficiency over constant-velocity control. This strategy uses the downhill simplex method to optimize control parameter profiles during operation of a model turbine in a recirculating water flume. This optimization method is extended to a set of two turbines, where the blade motions and position of the downstream turbine are optimized to beneficially interact with the coherent structures in the wake of the upstream turbine. This control scheme has the potential to enable high-density arrays of cross-flow turbines to operate at cost-effective efficiency. Turbine wake and force measurements are analyzed for insight into the effect of a coordinated control strategy.

  9. An electromagnetic/electrostatic dual cathode system for electron beam instruments

    NASA Technical Reports Server (NTRS)

    Bradley, J. G.; Conley, J. M.; Wittry, D. B.; Albee, A. L.

    1986-01-01

    A method of providing cathode redundancy which consists of two fixed cathodes and uses electromagnetic and/or electrostatic fields to direct the electron beam to the electron optical axis is presented, with application to the cathode system of the Scanning Electron Microscope and Particle Analyzer proposed for NASA's Mariner Mark II Comet Rendezvous/Asteroid Flyby projected for the 1990s. The symmetric double deflection system chosen has the optical property that the image of the effective electron source is formed above the magnet assembly near the apparent position of the effective source, and it makes the transverse positions of the electron sources independent of the electron beam energy. Good performance of the system is found, with the sample imaging resolution being the same as for the single-axis cathode.

  10. Utilization of Copper Alloys for Marine Applications

    NASA Astrophysics Data System (ADS)

    Drach, Andrew

    Utilization of copper alloy components in systems deployed in marine environment presents potential improvements by reducing maintenance costs, prolonging service life, and increasing reliability. However, integration of these materials faces technological challenges, which are discussed and addressed in this work, including characterization of material performance in seawater environment, hydrodynamics of copper alloy components, and design procedures for systems with copper alloys. To characterize the hydrodynamic behavior of copper alloy nets, mesh geometry of the major types of copper nets currently used in the marine aquaculture are analyzed and formulae for the solidity and strand length are proposed. Experimental studies of drag forces on copper alloy net panels are described. Based on these studies, empirical values for normal drag coefficients are proposed for various types of copper netting. These findings are compared to the previously published data on polymer nets. It is shown that copper nets exhibit significantly lower resistance to normal currents, which corresponds to lower values of normal drag coefficient. The seawater performance (corrosion and biofouling) of copper alloys is studied through the field trials of tensioned and untensioned specimens in a one-year deployment in the North Atlantic Ocean. The corrosion behavior is characterized by weight loss, optical microscopy, and SEM/EDX analyses. The biofouling performance is quantified in terms of the biomass accumulation. To estimate the effects of stray electrical currents on the seawater corrosion measurements, a low cost three-axis stray electric current monitoring device is designed and tested both in the lab and in the 30-day field deployment. The system consists of a remotely operated PC with a set of pseudo-electrodes and a digital compass. The collected data is processed to determine magnitudes of AC and DC components of electric field and dominant AC frequencies. Mechanical behavior of copper alloys is investigated through a series of uniaxial tension tests on virgin and weathered (after one-year deployment in the ocean) specimens. The changes in mechanical properties are quantified in terms of differences in Young's modulus, Poisson's ratio, ultimate strength, and ultimate strain. The obtained stress-strain data is used for numerical modeling of the mechanical behavior of chain-link nets. The simulations are compared with the experimental data on stiffness and strength of the nets. The available information on seawater performance of copper alloys (corrosion, biofouling, mechanics) and copper alloy nets (hydrodynamics) is used to develop engineering procedures for marine aquaculture fish cage systems with copper alloy netting. The design, analysis, and fabrication procedures are illustrated on a commercial size gravity-type offshore fish cage deployed in the Pacific Ocean near Isla Italia (Patagonia, Chile). The funding for this work was provided by the International Copper Association. This work was also supported through two UNH Fellowships: CEPS UNH Graduate Fellowship to Outstanding PhD Program Applicants and Dissertation Year Fellowship.

  11. The prediction of the hydrodynamic performance of tidal current turbines

    NASA Astrophysics Data System (ADS)

    Y Xiao, B.; Zhou, L. J.; Xiao, Y. X.; Wang, Z. W.

    2013-12-01

    Nowadays tidal current energy is considered to be one of the most promising alternative green energy resources and tidal current turbines are used for power generation. Prediction of the open water performance around tidal turbines is important for the reason that it can give some advice on installation and array of tidal current turbines. This paper presents numerical computations of tidal current turbines by using a numerical model which is constructed to simulate an isolated turbine. This paper aims at studying the installation of marine current turbine of which the hydro-environmental impacts influence by means of numerical simulation. Such impacts include free-stream velocity magnitude, seabed and inflow direction of velocity. The results of the open water performance prediction show that the power output and efficiency of marine current turbine varies from different marine environments. The velocity distribution should be clearly and the suitable unit installation depth and direction be clearly chosen, which can ensure the most effective strategy for energy capture before installing the marine current turbine. The findings of this paper are expected to be beneficial in developing tidal current turbines and array in the future.

  12. Charcterization of the Hypothalamic-Pituitary-Adrenal Axis Response to Atrazine and Metabolites in the Female Rat

    EPA Science Inventory

    Atrazine (ATR) has recently been shown to activate the hypothalamic-pituitary-adrenal (HPA) axis in rodents. The current study investigated the effect of ATR and two of its chlorinated metabolites, desisopropylatrazine (DIA) and diamino-s-chlorotriazine (DACT), on the HPA axis in...

  13. Purification of Proteins From Cell-Culture Medium or Cell-Lysate by High-Speed Counter-Current Chromatography Using Cross-Axis Coil Planet Centrifuge

    PubMed Central

    Shibusawa, Yoichi; Ito, Yoichiro

    2014-01-01

    This review describes protein purifications from cell culture medium or cell-lysate by high speed counter-current chromatography using the cross-axis coil planet centrifuge. Purifications were performed using aqueous two phase systems composed of polyethylene glycols and dextrans. PMID:25360182

  14. Endocannabinoid Signaling, Glucocorticoid-Mediated Negative Feedback and Regulation of the HPA Axis

    PubMed Central

    Hill, M. N.; Tasker, J. G.

    2012-01-01

    The hypothalamic-pituitary-adrenal (HPA) axis regulates the outflow of glucocorticoid hormones under basal conditions and in response to stress. Within the last decade, a large body of evidence has mounted indicating that the endocannabinoid system is involved in the central regulation of the stress response; however, the specific role endocannabinoid signalling plays in phases of HPA axis regulation, or the neural sites of action mediating this regulation, was not mapped out until recently. This review aims to collapse the current state of knowledge regarding the role of the endocannabinoid system in the regulation of the HPA axis to put together a working model of how and where endocannabinoids act within the brain to regulate outflow of the HPA axis. Specifically, we discuss the role of the endocannabinoid system in the regulation of the HPA axis under basal conditions, activation in response to acute stress and glucocorticoid-mediated negative feedback. Interestingly, there appears to be some anatomical specificity to the role of the endocannabinoid system in each phase of HPA axis regulation, as well as distinct roles of both anandamide and 2-arachidonoylglycerol in these phases. Ultimately, the current level of information indicates that endocannabinoid signalling acts to suppress HPA axis activity through concerted actions within the prefrontal cortex, amygdala and hypothalamus. PMID:22214537

  15. Marine Corps Drawdown, Force Structure Initiatives, and Roles and Missions: Background and Issues for Congress

    DTIC Science & Technology

    2014-01-09

    force of 150,000 Marines—a strength level Marine Corps leadership has characterized as unviable to execute our current defense strategy. The Marines...have instituted a number of force shaping programs to reach the 174,000 endstrength. They believe this force level can be achieved through natural...8 Current Planned Drawdown Levels

  16. Predicting Human Mobility Patterns in Marine Ecosystems: Entropy and Home Range Calculations Based on High-Resolution Fishing Vessel Tracking Data

    NASA Astrophysics Data System (ADS)

    Murawski, S. A.

    2016-02-01

    A number of recent studies have developed metrics of human mobility patterns based on georeferenced cell phone records. The studies generally indicate a high degree of predictability in human location and relatively narrow home ranges for most people. In marine ecosystems there are a number of important uses for such calculations including marine spatial planning and predicting the impacts of marine management options such as establishing marine protected areas (MPAs). In this study we use individual fishing vessel satellite tracking (VMS) records ( 30 million records) obtained from commercial reef fish fishing vessels in the Gulf of Mexico during 2006-2014. This period witnessed the establishment of a variety of new regulations including individual fishing quotas (IFQs) for snapper, grouper, and tilefish, establishment of spatial-area closures, and the temporary closure of as much as 85,000 nautical miles of productive fishing grounds associated with the Deepwater Horizon oil spill accident. Vessel positions were obtained, with a location frequency of one hour. From these VMS data we calculated three measures of entropy (degree of repeatability in spatial use), as well as calculated the axis of gyration (home range) for each vessel in the data set. These calculations were related to a variety of descriptor variables including vessel size, distance from home port to predominant fishing grounds, revenue generated on fishing trips, and fishing regulations. The applicability of these calculations to marine resource management applications is discussed.

  17. Corrigendum to "Characteristics of equatorial electrojet derived from Swarm satellites" [Adv. Space Res. 59 (2017) 1526-1538

    NASA Astrophysics Data System (ADS)

    Thomas, Neethal; Vichare, Geeta; Sinha, A. K.

    2018-02-01

    The authors regret that a typographical error in Abstract and Section 5 should be corrected. Figure 7b of Thomas et al. [2017] presents the variation of total westward return current (y-axis) with total eastward forward current (x-axis). The slopes vary between 1 and 0.1. This indicates that ratio of total westward return currents to total eastward forward current vary between 0.1 to 1. However in Abstract and Section 5, the authors have erroneously written the ratio as between "total eastward forward current to total westward return current".

  18. Os Odontoideum: Rare Cervical Lesion

    DTIC Science & Technology

    2011-11-01

    abnormality of the second cervical vertebrae in which the odontoid process is separated from the body of the axis by a transverse gap.1 This lesion... cervical region of his posterior neck. The patient was an active duty Marine Corps Private First Class with no significant medical history or history of head...within normal limits. His head was atraumatic. Patient had palpable midline posterior cervical spinal tenderness along C1 to C2 with no step-offs noted

  19. Current profile redistribution driven by neutral beam injection in a reversed-field pinch

    NASA Astrophysics Data System (ADS)

    Parke, E.; Anderson, J. K.; Brower, D. L.; Den Hartog, D. J.; Ding, W. X.; Johnson, C. A.; Lin, L.

    2016-05-01

    Neutral beam injection in reversed-field pinch (RFP) plasmas on the Madison Symmetric Torus [Dexter et al., Fusion Sci. Technol. 19, 131 (1991)] drives current redistribution with increased on-axis current density but negligible net current drive. Internal fluctuations correlated with tearing modes are observed on multiple diagnostics; the behavior of tearing mode correlated structures is consistent with flattening of the safety factor profile. The first application of a parametrized model for island flattening to temperature fluctuations in an RFP allows inferrence of rational surface locations for multiple tearing modes. The m = 1, n = 6 mode is observed to shift inward by 1.1 ± 0.6 cm with neutral beam injection. Tearing mode rational surface measurements provide a strong constraint for equilibrium reconstruction, with an estimated reduction of q0 by 5% and an increase in on-axis current density of 8% ± 5%. The inferred on-axis current drive is consistent with estimates of fast ion density using TRANSP [Goldston et al., J. Comput. Phys. 43, 61 (1981)].

  20. Polar solar wind and interstellar wind properties from interplanetary Lyman-alpha radiation measurements

    NASA Technical Reports Server (NTRS)

    Witt, N.; Blum, P. W.; Ajello, J. M.

    1981-01-01

    The analysis of Mariner 10 observations of Lyman-alpha resonance radiation shows an increase of interplanetary neutral hydrogen densities above the solar poles. This increase is caused by a latitudinal variation of the solar wind velocity and/or flux. Using both the Mariner 10 results and other solar wind observations, the values of the solar wind flux and velocity with latitude are determined for several cases of interest. The latitudinal variation of interplanetary hydrogen gas, arising from the solar wind latitudinal variation, is shown to be most pronounced in the inner solar system. From this result it is shown that spacecraft Lyman-alpha observations are more sensitive to the latitudinal anisotropy for a spacecraft location in the inner solar system near the downwind axis.

  1. Out of sight, out of mind: threats to the marine biodiversity of the Canary Islands (NE Atlantic Ocean).

    PubMed

    Riera, Rodrigo; Becerro, Mikel A; Stuart-Smith, Rick D; Delgado, Juan D; Edgar, Graham J

    2014-09-15

    Lack of knowledge of the marine realm may bias our perception of the current status and threats to marine biodiversity. Less than 10% of all ecological literature is related to the ocean, and the information we have on marine species that are threatened or on the verge of extinction is scarce. This lack of information is particularly critical for isolated areas such as oceanic archipelagos. Here we review published and grey literature on the current status of marine organisms in the Canary Islands as a case description of the consequences that current out-of-sight out-of-mind attitudes may have on this unique environment. Global change, as represented by coastal development, pollution, exotic species and climate change, are currently affecting the distribution and abundance of Canarian marine organisms, and pose multiple threats to local species and communities. Environmental risks are significant at community and species levels, particularly for threatened species. Failure to address these trends will result in shifts in local biodiversity with important ecological, social, and economic consequences. Scientists, policy makers, educators, and relevant societal groups need to collaborate to reverse deleterious coastal biodiversity trends. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Psychiatric Comorbidities among Female Adolescents with Anorexia Nervosa

    ERIC Educational Resources Information Center

    Salbach-Andrae, Harriet; Lenz, Klaus; Simmendinger, Nicole; Klinkowski, Nora; Lehmkuhl, Ulrike; Pfeiffer, Ernst

    2008-01-01

    This study investigated current comorbid Axis I diagnoses associated with Anorexia Nervosa (AN) in adolescents. The sample included 101 female adolescents treated at a psychiatric unit for primary DSM-IV diagnoses of AN. 73.3% of the AN patients were diagnosed as having a current comorbidity of at least one comorbid Axis I diagnosis, with no…

  3. Numerical investigation of flow motion and performance of a horizontal axis tidal turbine subjected to a steady current

    NASA Astrophysics Data System (ADS)

    Li, Lin-juan; Zheng, Jin-hai; Peng, Yu-xuan; Zhang, Ji-sheng; Wu, Xiu-guang

    2015-04-01

    Horizontal axis tidal turbines have attracted more and more attentions nowadays, because of their convenience and low expense in construction and high efficiency in extracting tidal energy. The present study numerically investigates the flow motion and performance of a horizontal axis tidal turbine with a supporting vertical cylinder under steady current. In the numerical model, the continuous equation and incompressible Reynolds-averaged Navier-Stokes equations are solved, and the volume of fluid method is employed to track free surface motion. The RNG k- ɛ model is adopted to calculate turbulence transport while the fractional area/volume obstacle representation method is used to describe turbine characteristics and movement. The effects of installation elevation of tidal turbine and inlet velocity on the water elevation, and current velocity, rotating speed and resultant force on turbine are discussed. Based on the comparison of the numerical results, a better understanding of flow structure around horizontal axis tidal turbine and turbine performance is achieved.

  4. Effects of currents and tides on fine-scale use of marine bird habitats in a Southeast Alaska hotspot

    USGS Publications Warehouse

    Drew, Gary S.; Piatt, John F.; Hill, David J.

    2013-01-01

    Areas with high species richness have become focal points in the establishment of marine protected areas, but an understanding of the factors that support this diversity is still incomplete. In coastal areas, tidal currents—modulated by bathymetry and manifested in variable speeds—are a dominant physical feature of the environment. However, difficulties resolving tidally affected currents and depths at fine spatial-temporal scales have limited our ability to understand their influence the distribution of marine birds. We used a hydrographic model of the water mass in Glacier Bay, Alaska to link depths and current velocities with the locations of 15 common marine bird species observed during fine-scale boat-based surveys of the bay conducted during June of four consecutive years (2000-2003). Marine birds that forage on the bottom tended to occupy shallow habitats with slow-moving currents; mid-water foragers used habitats with intermediate depths and current speeds; and surface-foraging species tended to use habitats with fast-moving, deep waters. Within foraging groups there was variability among species in their use of habitats. While species obligated to foraging near bottom were constrained to use similar types of habitat, species in the mid-water foraging group were associated with a wider range of marine habitat characteristics. Species also showed varying levels of site use depending on tide stage. The dramatic variability in bottom topography—especially the presence of numerous sills, islands, headlands and channels—and large tidal ranges in Glacier Bay create a wide range of current-affected fine-scale foraging habitats that may contribute to the high diversity of marine bird species found there.

  5. Petroleum system and production characteristics of the Muddy (J) Sandstone (Lower Cretaceous) Wattenberg continuous gas field, Denver basin, Colorado

    USGS Publications Warehouse

    Higley, D.K.; Cox, D.O.; Weimer, R.J.

    2003-01-01

    Wattenberg field is a continuous-type gas accumulation. Estimated ultimate recovery from current wells is 1.27 tcf of gas from the Lower Cretaceous Muddy (J) Sandstone. Mean gas resources that have the potential to be added to these reserves in the next 30 yr are 1.09 tcf; this will be primarily through infill drilling to recover a greater percentage of gas in place and to drain areas that are isolated because of geologic compartmentalization. Greatest gas production from the Muddy (J) Sandstone in Wattenberg field occurs (1) from within the most permeable and thickest intervals of Fort Collins Member delta-front and nearshore-marine sandstones, (2) to a lesser extent from the Horsetooth Member valley-fill channel sandstones, (3) in association with a large thermal anomaly that is delineated by measured temperatures in wells and by vitrinite reflectance contours of 0.9% and greater, (4) in proximity to the bounding Mowry, Graneros, and Skull Creek shales that are the hydrocarbon source rocks and reservoir seals, and (5) between the Lafayette and Longmont right-lateral wrench fault zones (WFZs) with secondary faults that act as conduits in areas of the field. The axis of greatest gas production is north 25 to 35?? northeast, which parallels the basin axis. Recurrent movement along five right-lateral WFZs that crosscut Wattenberg field shifted the Denver basin axis to the northeast and influenced depositional and erosional patterns of the reservoir and seal intervals. Levels of thermal maturity within the Wattenberg field are anomalously high compared to other areas of the Denver basin. The Wattenberg field thermal anomaly may be due to upward movement of fluids along faults associated with probable igneous intrusions. Areas of anomalous high heat flow within the field correlate with an increased and variable gas-oil ratio.

  6. Numerical performance analysis of acoustic Doppler velocity profilers in the wake of an axial-flow marine hydrokinetic turbine

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

    Richmond, Marshall C.; Harding, Samuel F.; Romero Gomez, Pedro DJ

    The use of acoustic Doppler current profilers (ADCPs) for the characterization of flow conditions in the vicinity of both experimental and full scale marine hydrokinetic (MHK) turbines is becoming increasingly prevalent. The computation of a three dimensional velocity measurement from divergent acoustic beams requires the assumption that the flow conditions are homogeneous between all beams at a particular axial distance from the instrument. In the near wake of MHK devices, the mean fluid motion is observed to be highly spatially dependent as a result of torque generation and energy extraction. This paper examines the performance of ADCP measurements in suchmore » scenarios through the modelling of a virtual ADCP (VADCP) instrument in the velocity field in the wake of an MHK turbine resolved using unsteady computational fluid dynamics (CFD). This is achieved by sampling the CFD velocity field at equivalent locations to the sample bins of an ADCP and performing the coordinate transformation from beam coordinates to instrument coordinates and finally to global coordinates. The error in the mean velocity calculated by the VADCP relative to the reference velocity along the instrument axis is calculated for a range of instrument locations and orientations. The stream-wise velocity deficit and tangential swirl velocity caused by the rotor rotation lead to significant misrepresentation of the true flow velocity profiles by the VADCP, with the most significant errors in the transverse (cross-flow) velocity direction.« less

  7. Development of 3-axis precise positioning seismic physical modeling system in the simulation of marine seismic exploration

    NASA Astrophysics Data System (ADS)

    Kim, D.; Shin, S.; Ha, J.; Lee, D.; Lim, Y.; Chung, W.

    2017-12-01

    Seismic physical modeling is a laboratory-scale experiment that deals with the actual and physical phenomena that may occur in the field. In seismic physical modeling, field conditions are downscaled and used. For this reason, even a small error may lead to a big error in an actual field. Accordingly, the positions of the source and the receiver must be precisely controlled in scale modeling. In this study, we have developed a seismic physical modeling system capable of precisely controlling the 3-axis position. For automatic and precise position control of an ultrasonic transducer(source and receiver) in the directions of the three axes(x, y, and z), a motor was mounted on each of the three axes. The motor can automatically and precisely control the positions with positional precision of 2''; for the x and y axes and 0.05 mm for the z axis. As it can automatically and precisely control the positions in the directions of the three axes, it has an advantage in that simulations can be carried out using the latest exploration techniques, such as OBS and Broadband Seismic. For the signal generation section, a waveform generator that can produce a maximum of two sources was used, and for the data acquisition section, which receives and stores reflected signals, an A/D converter that can receive a maximum of four signals was used. As multiple sources and receivers could be used at the same time, the system was set up in such a way that diverse exploration methods, such as single channel, multichannel, and 3-D exploration, could be realized. A computer control program based on LabVIEW was created, so that it could control the position of the transducer, determine the data acquisition parameters, and check the exploration data and progress in real time. A marine environment was simulated using a water tank 1 m wide, 1 m long, and 0.9 m high. To evaluate the performance and applicability of the seismic physical modeling system developed in this study, single channel and multichannel explorations were carried out in the marine environment and the accuracy of the modeling system was verified by comparatively analyzing the exploration data and the numerical modeling data acquired.

  8. Method and apparatus for maintaining equilibrium in a helical axis stellarator

    DOEpatents

    Reiman, Allan; Boozer, Allen

    1987-01-01

    Apparatus for maintaining three-dimensional MHD equilibrium in a plasma contained in a helical axis stellerator includes a resonant coil system, having a configuration such that current therethrough generates a magnetic field cancelling the resonant magnetic field produced by currents driven by the plasma pressure on any given flux surface resonating with the rotational transform of another flux surface in the plasma. Current through the resonant coil system is adjusted as a function of plasma beta.

  9. Method and apparatus for maintaining equilibrium in a helical axis stellarator

    DOEpatents

    Reiman, A.; Boozer, A.

    1984-10-31

    Apparatus for maintaining three-dimensional MHD equilibrium in a plasma contained in a helical axis stellarator includes a resonant coil system, having a configuration such that current therethrough generates a magnetic field cancelling the resonant magnetic field produced by currents driven by the plasma pressure on any given flux surface resonating with the rotational transform of another flux surface in the plasma. Current through the resonant coil system is adjusted as a function of plasma beta.

  10. Are greenhouse gas emissions from international shipping a type of marine pollution?

    PubMed

    Shi, Yubing

    2016-12-15

    Whether greenhouse gas emissions from international shipping are a type of marine pollution is a controversial issue and is currently open to debate. This article examines the current treaty definitions of marine pollution, and applies them to greenhouse gas emissions from ships. Based on the legal analysis of treaty definitions and relevant international and national regulation on this issue, this article asserts that greenhouse gas emissions from international shipping are a type of 'conditional' marine pollution. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Alabama 4-H Marine Pilot Manual.

    ERIC Educational Resources Information Center

    Rawson, Mac; Trussell, Gale

    Brief descriptions and eight activities related to zooplankton, sharks, dune ecology, ocean currents, and sea products comprise this manual. Among the activities are harvesting seafood, making Japanese fish prints, and tracing marine currents with drift bottles. (WB)

  12. Global mismatch between fishing dependency and larval supply from marine reserves

    NASA Astrophysics Data System (ADS)

    Andrello, Marco; Guilhaumon, François; Albouy, Camille; Parravicini, Valeriano; Scholtens, Joeri; Verley, Philippe; Barange, Manuel; Sumaila, U. Rashid; Manel, Stéphanie; Mouillot, David

    2017-07-01

    Marine reserves are viewed as flagship tools to protect exploited species and to contribute to the effective management of coastal fisheries. Yet, the extent to which marine reserves are globally interconnected and able to effectively seed areas, where fisheries are most critical for food and livelihood security is largely unknown. Using a hydrodynamic model of larval dispersal, we predict that most marine reserves are not interconnected by currents and that their potential benefits to fishing areas are presently limited, since countries with high dependency on coastal fisheries receive very little larval supply from marine reserves. This global mismatch could be reversed, however, by placing new marine reserves in areas sufficiently remote to minimize social and economic costs but sufficiently connected through sea currents to seed the most exploited fisheries and endangered ecosystems.

  13. Power-Factor and Torque Calculation under Consideration of Cross Saturation of the Interior Permanent Magnet Synchronous Motor with Brushless Field Excitation

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

    Lee, Seong T; Burress, Timothy A; Tolbert, Leon M

    2009-01-01

    This paper introduces a new method for calculating the power factor and output torque by considering the cross saturation between direct-axis (d-axis) and quadrature-axis (q-axis) of an interior permanent magnet synchronous motor (IPMSM). The conventional two-axis IPMSM model is modified to include the cross saturation effect by adding the cross-coupled inductance terms. This paper also contains the new method of calculating the cross-coupled inductance values as well as self-inductance values in d- and q-axes. The analyzed motor is a high-speed brushless field excitation machine that offers high torque per ampere per core length at low speed and weakened flux atmore » high speed, which was developed for the traction motor of a hybrid electric vehicle. The conventional two-axis IPMSM model was modified to include the cross-saturation effect by adding the cross-coupled inductance terms Ldq and Lqd. By the advantage of the excited structure of the experimental IPMSM, the analyzing works were performed under two conditions, the highest and lowest excited conditions. Therefore, it is possible to investigate the cross-saturation effect when a machine has higher magnetic flux from its rotor. The following is a summary of conclusions that may be drawn from this work: (1) Considering cross saturation of an IPMSM offers more accurate expected values of motor parameters in output torque calculation, especially when negative d-axis current is high; (2) A less saturated synchronous machine could be more affected by the cross-coupled saturation effect; (3) Both cross-coupled inductances, L{sub qd} and L{sub dq}, are mainly governed by d-axis current rather than q-axis current; (4) The modified torque equation, can be used for the dynamic model of an IPMSM for developing a better control model or control strategy; and (5) It is possible that the brushless field excitation structure has a common magnetic flux path on both d- and q-axis, and as a result, the reluctance torque of the machine could be reduced.« less

  14. The Bottlenose Dolphin (Tursiops truncatus) as a Model to Understand Variation in Stress and Reproductive Hormone Measures in Relation to Sampling Matrix, Demographics, and Environmental Factors

    DTIC Science & Technology

    2015-09-30

    ranging individuals support the existence of these same stress response pathways in marine mammals. 2 While the HPA axis and physiological processes...relying upon methods which include capture-release health assessments. Stress and reproductive hormones (cortisol, aldosterone , thyroid, testosterone...Analyses Hormone concentrations (cortisol, aldosterone , reproductive and thyroid hormones) in serum samples were analyzed by Cornell’s Animal Health

  15. The Marine Geochemistry of Iron and Iron Isotopes

    DTIC Science & Technology

    2004-09-01

    suspension of sediments, and hydrothermal vents. A schematic of the Fe cycle in the open ocean is shown in Figure 1.1. Fe concentrations are highest near...than 2% of their coastal values 100 km from the California continental margin (JOHNSON et al., 1997). Hydrothermal input of Fe is believed to be...important only near its sources (mostly in the deep ocean) because most of the Fe from hydrothermal vents precipitates near the vents and ridge axis (DE

  16. Mars synthetic topographic mapping

    USGS Publications Warehouse

    Wu, S.S.C.

    1978-01-01

    Topographic contour maps of Mars are compiled by the synthesis of data acquired from various scientific experiments of the Mariner 9 mission, including S-band radio-occulation, the ultraviolet spectrometer (UVS), the infrared radiometer (IRR), the infrared interferometer spectrometer (IRIS) and television imagery, as well as Earth-based radar information collected at Goldstone, Haystack, and Arecibo Observatories. The entire planet is mapped at scales of 1:25,000,000 and 1:25,000,000 using Mercator, Lambert, and polar stereographic map projections. For the computation of map projections, a biaxial spheroid figure is adopted. The semimajor and semiminor axes are 3393.4 and 3375.7 km, respectively, with a polar flattening of 0.0052. For the computation of elevations, a topographic datum is defined by a gravity field described in terms of spherical harmonics of fourth order and fourth degree combined with a 6.1-mbar occulation pressure surface. This areoid can be approximated by a triaxial ellipsoid with semimajor axes of A = 3394.6 km and B = 3393.3 km and a semiminor axis of C = 3376.3 km. The semimajor axis A intersects the Martian surface at longitude 105??W. The dynamic flattening of Mars is 0.00525. The contour intercal of the maps is 1 km. For some prominent features where overlapping pictures from Mariner 9 are available, local contour maps at relatively larger scales were also compiled by photogrammetric methods on stereo plotters. ?? 1978.

  17. Analysis of off-axis solenoid fields using the magnetic scalar potential: An application to a Zeeman-slower for cold atoms

    NASA Astrophysics Data System (ADS)

    Muniz, Sérgio R.; Bagnato, Vanderlei S.; Bhattacharya, M.

    2015-06-01

    In a region free of currents, magnetostatics can be described by the Laplace equation of a scalar magnetic potential, and one can apply the same methods commonly used in electrostatics. Here, we show how to calculate the general vector field inside a real (finite) solenoid, using only the magnitude of the field along the symmetry axis. Our method does not require integration or knowledge of the current distribution and is presented through practical examples, including a nonuniform finite solenoid used to produce cold atomic beams via laser cooling. These examples allow educators to discuss the nontrivial calculation of fields off-axis using concepts familiar to most students, while offering the opportunity to introduce themes of current modern research.

  18. Biological Significance of Acoustic Impacts on Marine Mammals: Examples Using an Acoustic Recording tag to Define Acoustic Exposure of Sperm Whales, Physeter catodon, Exposed to Airgun Sounds in Controlled Exposure Experiments

    NASA Astrophysics Data System (ADS)

    Tyack, P. L.; Johnson, M. P.; Madsen, P. T.; Miller, P. J.; Lynch, J.

    2006-05-01

    There has been considerable debate about how to regulate behavioral disruption in marine mammals. The U.S. Marine Mammal Protection Act prohibits "taking" marine mammals, including harassment, which is defined as injury or disruption of behavioral patterns. A 2005 report by the National Academy of Sciences focuses on the need to analyze acoustic impacts on marine mammal behavior in terms of biological significance. The report develops a model for predicting population consequences of acoustic impacts. One of the key data gaps involves methods to estimate the impact of disruption on an animal's ability to complete life functions critical for growth, survival, and reproduction. One of the few areas where theory and data are available involves foraging energetics. Patrick Miller in the next talk and I will discuss an example study designed to evaluate the impact of exposure to seismic survey on the foraging energetics of sperm whales. As petroleum exploration moves offshore to deep water, there is increasing overlap between seismic exploration and deep diving toothed whales such as the sperm whale which is listed by the US as an endangered species. With support from the US Minerals Management Service and the Industry Research Funding Coalition, we tagged sperm whales with tags that can record sound, orientation, acceleration, temperature and depth. Eight whales tagged in the Gulf of Mexico during 2002-2003 were subjects in 5 controlled experiments involving exposure to sounds of an airgun array. One critical component of evaluating effects involves quantifying exposure at the animal. While the on-axis signature of airgun arrays has been well quantified, there are few broadband calibrated measurements in the water column displaced horizontally away from the downward-directed beam. The acoustic recording tags provide direct data on sounds as received at the animals. Due to multipath propagation, multiple sound pulses were recorded on the tagged whales for each firing of the array with received levels of analyzed pulses falling between 131-167 dB re. 1μPa (pp) [111-147 dB re. 1μPa (rms) & 100-135 dB re. 1μPa2s]. The acoustic energy produced by airguns centers in the 50-250 Hz band, with spectral levels about 40 dB lower at 1 kHz for the on-axis signature. However, some arrivals recorded near the surface in 2002 had energy predominantly above 500Hz. A surface duct in the 2002 sound speed profile had a cutoff frequency calculated at 250 Hz. Poor propagation below this cutoff and efficient propagation above it helps to explain this effect. Our empirical measurements demonstrate that airguns expose animals to significant sound energy above 500Hz, which increases concern about the potential impact on toothed whales with poor low frequency hearing. The measurements are consistent with ray trace and parabolic equation propagation models, which can predict the relative timing of the multipath arrivals. The results indicate that on-axis source levels and simple spreading assumptions alone cannot predict airgun pulse propagation and the extent of exposure zones.

  19. Comorbidity in adults with attention-deficit hyperactivity disorder.

    PubMed

    Cumyn, Lucy; French, Lisa; Hechtman, Lily

    2009-10-01

    To examine the prevalence of comorbid Axis I (current and lifetime) and II disorders in adult men and women with attention-deficit hyperactivity disorder (ADHD). Adult patients (n = 447; 266 men, 181 women) received comprehensive assessments for ADHD and Axis I and II disorders. Adults were aged between 17 and 74 years. Among the patients diagnosed with ADHD (n = 335), there were those with ADHD inattentive subtype (ADHD-I) (n = 199), hyperactive-impulsive subtype (ADHD-H) (n = 24), or combined ADHD subtype (ADHD-C) (n = 112). Chi-square and logistic regression analyses were performed to examine associations between adults with and without ADHD on Axis I and II disorders. Adults with ADHD, compared with those without ADHD, had higher rates of Axis I (46.9% and 27.31%) and Axis II (50.7% and 38.2%) disorders. Adults with ADHD-C were more likely to have mood disorder, anxiety, conduct disorder, and substance use disorder as well as obsessive-compulsive personality disorder, passive-aggressive personality disorder, depressive personality disorder, narcissistic personality disorder, and borderline personality disorder (BPD). Men with ADHD were more likely to have antisocial personality disorder and had higher rates of current drug abuse than women with ADHD. Women with ADHD had higher rates of past and current panic disorder, and past anorexia and bulimia. Women with ADHD were more likely to have BPD than men with ADHD. Adults with ADHD have very high rates of comorbid Axis I and II disorders, with differences found between men and women on certain comorbid disorders.

  20. Current profile redistribution driven by neutral beam injection in a reversed-field pinch

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

    Parke, E.; Department of Physics, University of Wisconsin-Madison 1150 University Ave., Madison, Wisconsin 53706; Anderson, J. K.

    2016-05-15

    Neutral beam injection in reversed-field pinch (RFP) plasmas on the Madison Symmetric Torus [Dexter et al., Fusion Sci. Technol. 19, 131 (1991)] drives current redistribution with increased on-axis current density but negligible net current drive. Internal fluctuations correlated with tearing modes are observed on multiple diagnostics; the behavior of tearing mode correlated structures is consistent with flattening of the safety factor profile. The first application of a parametrized model for island flattening to temperature fluctuations in an RFP allows inferrence of rational surface locations for multiple tearing modes. The m = 1, n = 6 mode is observed to shift inward by 1.1 ± 0.6 cm withmore » neutral beam injection. Tearing mode rational surface measurements provide a strong constraint for equilibrium reconstruction, with an estimated reduction of q{sub 0} by 5% and an increase in on-axis current density of 8% ± 5%. The inferred on-axis current drive is consistent with estimates of fast ion density using TRANSP [Goldston et al., J. Comput. Phys. 43, 61 (1981)].« less

  1. The subject-fixated coaxially sighted corneal light reflex: a clinical marker for centration of refractive treatments and devices.

    PubMed

    Chang, Daniel H; Waring, George O

    2014-11-01

    To describe the inconsistencies in definition, application, and usage of the ocular reference axes (optical axis, visual axis, line of sight, pupillary axis, and topographic axis) and angles (angle kappa, lambda, and alpha) and to propose a precise, reproducible, clinically defined reference marker and axis for centration of refractive treatments and devices. Perspective. Literature review of papers dealing with ocular reference axes, angles, and centration. The inconsistent definitions and usage of the current ocular axes, as derived from eye models, limit their clinical utility. With a clear understanding of Purkinje images and a defined alignment of the observer, light source/fixation target, and subject eye, the subject-fixated coaxially sighted corneal light reflex can be a clinically useful reference marker. The axis formed by connecting the subject-fixated coaxially sighted corneal light reflex and the fixation point, the subject-fixated coaxially sighted corneal light reflex axis, is independent of pupillary dilation and phakic status of the eye. The relationship of the subject-fixated coaxially sighted corneal light reflex axis to a refined definition of the visual axis without reference to nodal points, the foveal-fixation axis, is discussed. The displacement between the subject-fixated coaxially sighted corneal light reflex and pupil center is described not by an angle, but by a chord, here termed chord mu. The application of the subject-fixated coaxially sighted corneal light reflex to the surgical centration of refractive treatments and devices is discussed. As a clinically defined reference marker, the subject-fixated coaxially sighted corneal light reflex avoids the shortcomings of current ocular axes for clinical application and may contribute to better consensus in the literature and improved patient outcomes. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Marine Resources and Legal-Political Arrangements for Their Development; Volume 3, Panel Reports of the Commission on Marine Science, Engineering and Resources.

    ERIC Educational Resources Information Center

    Commission on Marine Science, Engineering and Resources, Washington, DC.

    The Marine Resources Panel addressed itself to three tasks: describing the current rate of exploration and exploitation of marine resources and the physical, economic, and legal conditions under which they are produced; identifying deterrents to development and efficient utilization of marine resources; and recommending programs that will remove…

  3. HIGH CURRENT RADIO FREQUENCY ION SOURCE

    DOEpatents

    Abdelaziz, M.E.

    1963-04-01

    This patent relates to a high current radio frequency ion source. A cylindrical plasma container has a coil disposed around the exterior surface thereof along the longitudinal axis. Means are provided for the injection of an unionized gas into the container and for applying a radio frequency signal to the coil whereby a radio frequency field is generated within the container parallel to the longitudinal axis thereof to ionize the injected gas. Cathode and anode means are provided for extracting transverse to the radio frequency field from an area midway between the ends of the container along the longitudinal axis thereof the ions created by said radio frequency field. (AEC)

  4. Global mismatch between fishing dependency and larval supply from marine reserves

    PubMed Central

    Andrello, Marco; Guilhaumon, François; Albouy, Camille; Parravicini, Valeriano; Scholtens, Joeri; Verley, Philippe; Barange, Manuel; Sumaila, U. Rashid; Manel, Stéphanie; Mouillot, David

    2017-01-01

    Marine reserves are viewed as flagship tools to protect exploited species and to contribute to the effective management of coastal fisheries. Yet, the extent to which marine reserves are globally interconnected and able to effectively seed areas, where fisheries are most critical for food and livelihood security is largely unknown. Using a hydrodynamic model of larval dispersal, we predict that most marine reserves are not interconnected by currents and that their potential benefits to fishing areas are presently limited, since countries with high dependency on coastal fisheries receive very little larval supply from marine reserves. This global mismatch could be reversed, however, by placing new marine reserves in areas sufficiently remote to minimize social and economic costs but sufficiently connected through sea currents to seed the most exploited fisheries and endangered ecosystems. PMID:28691710

  5. Transverse-displacement stabilizer for passive magnetic bearing systems

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

    Post, Richard F

    The invention provides a way re-center a rotor's central longitudinal rotational axis with a desired system longitudinal axis. A pair of planar semicircular permanent magnets are pieced together to form a circle. The flux from each magnet is pointed in in opposite directions that are both parallel with the rotational axis. A stationary shorted circular winding the plane of which is perpendicular to the system longitudinal axis and the center of curvature of the circular winding is positioned on the system longitudinal axis. Upon rotation of the rotor, when a transverse displacement of the rotational axis occurs relative to themore » system longitudinal axis, the winding will experience a time-varying magnetic flux such that an alternating current that is proportional to the displacement will flow in the winding. Such time-varying magnetic flux will provide a force that will bring the rotor back to its centered position about the desired axis.« less

  6. Large submarine sand waves and gravel lag substrates on Georges Bank off Atlantic Canada

    USGS Publications Warehouse

    Todd, B.J.; Valentine, Page C.; Harris, Peter T; Baker, E.K.

    2012-01-01

    Georges Bank is a large, shallow, continental shelf feature offshore of New England and Atlantic Canada. The bank is mantled with a veneer of glacial debris transported during the late Pleistocene from continental areas lying to the north. These sediments were reworked by marine processes during postglacial sea-level transgression and continue to be modified by the modern oceanic regime. The surficial geology of the Canadian portion of the bank is a widespread gravel lag overlain in places by well sorted sand occurring as bedforms. The most widespread bedforms are large, mobile, asymmetrical sand waves up to 19 m in height formed through sediment transport by strong tidal-driven and possibly storm-driven currents. Well-defined curvilinear bedform crests up to 15 km long form a complex bifurcating pattern having an overall southwest–northeast strike, which is normal to the direction of the major axis of the semidiurnal tidal current ellipse. Minor fields of immobile, symmetrical sand waves are situated in bathymetric lows. Rare mobile, asymmetrical barchan dunes are lying on the gravel lag in areas of low sand supply. On Georges Bank, the management of resources and habitats requires an understanding of the distribution of substrate types, their surface dynamics and susceptibility to movement, and their associated fauna.

  7. Department of Energy WindSentinel Loan Program Description

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

    Shaw, William J.; Sturges, Mark H.

    The U.S. Department of Energy (DOE) currently owns two AXYS WindSentinel buoys that collect a comprehensive set of meteorological and oceanographic data to support resource characterization for wind energy offshore. The two buoys were delivered to DOE’s Pacific Northwest National Laboratory (PNNL) in September, 2014. After acceptance testing and initial performance testing and evaluation at PNNL’s Marine Sciences Laboratory in Sequim, Washington, the buoys have been deployed off the U.S. East Coast. One buoy was deployed approximately 42 km east of Virginia Beach, Virginia from December, 2014 through June, 2016. The second buoy was deployed approximately 5 km off Atlanticmore » City, New Jersey in November, 2015. Data from the buoys are available to the public. Interested parties can create an account and log in to http://offshoreweb.pnnl.gov. In response to a number of inquiries and unsolicited proposals, DOE’s Wind Energy Technologies Office is implementing a program, to be managed by PNNL, to lend the buoys to qualified parties for the purpose of acquiring wind resource characterization data in areas of interest for offshore wind energy development. This document describes the buoys, the scope of the loans, the process of how borrowers will be selected, and the schedule for implementation of this program, including completing current deployments.« less

  8. The Source Book of Marine Sciences.

    ERIC Educational Resources Information Center

    Beakley, John C.; And Others

    Included is a teachers resource collection of 42 marine science activities for high school students. Both the biological and the physical factors of the marine environment are investigated, including the study of tides, local currents, microscope measuring, beaches, turbidity, sea water solids, pH, and salinity, marine bacteriology, microbiology,…

  9. A comprehensive Two-Fluid Model for Cavitation and Primary Atomization Modelling of liquid jets - Application to a large marine Diesel injector

    NASA Astrophysics Data System (ADS)

    Habchi, Chawki; Bohbot, Julien; Schmid, Andreas; Herrmann, Kai

    2015-12-01

    In this paper, a comprehensive two-fluid model is suggested in order to compute the in-nozzle cavitating flow and the primary atomization of liquid jets, simultaneously. This model has been applied to the computation of a typical large marine Diesel injector. The numerical results have shown a strong correlation between the in-nozzle cavitating flow and the ensuing spray orientation and atomization. Indeed, the results have confirmed the existence of an off-axis liquid core. This asymmetry is likely to be at the origin of the spray deviation observed experimentally. In addition, the primary atomization begins very close to the orifice exit as in the experiments, and the smallest droplets are generated due to cavitation pocket shape oscillations located at the same side, inside the orifice.

  10. C-axis orientated AlN films deposited using deep oscillation magnetron sputtering

    NASA Astrophysics Data System (ADS)

    Lin, Jianliang; Chistyakov, Roman

    2017-02-01

    Highly <0001> c-axis orientated aluminum nitride (AlN) films were deposited on silicon (100) substrates by reactive deep oscillation magnetron sputtering (DOMS). No epitaxial favored bond layer and substrate heating were applied for assisting texture growth. The effects of the peak target current density (varied from 0.39 to 0.8 Acm-2) and film thickness (varied from 0.25 to 3.3 μm) on the c-axis orientation, microstructure, residual stress and mechanical properties of the AlN films were investigated by means of X-ray diffraction rocking curve methodology, transmission electron microscopy, optical profilometry, and nanoindentation. All AlN films exhibited a <0001> preferred orientation and compressive residual stresses. At similar film thicknesses, an increase in the peak target current density to 0.53 Acm-2 improved the <0001> orientation. Further increasing the peak target current density to above 0.53 Acm-2 showed limited contribution to the texture development. The study also showed that an increase in the thickness of the AlN films deposited by DOMS improved the c-axis alignment accompanied with a reduction in the residual stress.

  11. Crystal alignments in the Fast ice of arctic Alaska

    NASA Astrophysics Data System (ADS)

    Weeks, W. F.; Gow, A. J.

    1980-02-01

    Field observations at 60 sites located in the fast or near-fast ice along a 1200-km stretch of the north coast of Alaska between the Bering Strait and Barter Island have shown that the great majority of the ice samples (95%) exhibit striking c axis alignments within the horizontal plane. In all cases the degree of preferred orientation increased with depth in the ice. Representative standard deviations around a mean direction in the horizontal plane are commonly less than ±10° for samples collected near the bottom of the ice. At a given site the mean c axis direction ?0 may vary as much as 20° with vertical location in the ice sheet. The c axis allignments in the nearshore region generally parallel the coast, with strong alignments occurring in the lagoon systems between the barrier islands and the coast and seaward of the barrier islands. In passes between islands and in entrances such as the opening to Kotzebue Sound the alignment is parallel to the channel. Only limited observations are available farther seaward over the inner (10- to 50-m isobaths) and outer (50-m isobath to shelf break) shelf regions. These indicate NE-SW and E-W alignments, respectively, in the Beaufort Sea north of Prudhoe Bay. The general patterns of the alignments support the correlation between the preferred c axis direction and the current direction at the ice/water interface suggested by Weeks and Gow (1978). A comparison between c axis alignments and instantaneous current measurements made at 42 locations shows that the most frequent current direction coincides with ?0. At the one site where we were able to determine the current direction (52°T) over a longer period (7 hours), the agreement with ?0. (48°T) was excellent. Similarly, if only ?0. values determined in the nearshore region are considered, the most frequent deviation is 10° or less between ?0. and the trend of the adjacent shoreline, which is presumably parallel to the prevailing longshore currents. The c axis alignments are believed to be the result of geometric selection, with the most favored orientation being that in which the current flows normal to the (0001) plates of ice that comprise the dendritic sea ice/seawater interface. The instantaneous current observations suggest SW nearshore currents along the Chukchi coast between SW of Point Lay and SW of the Rogers-Post Monument. In the vicinity of Barrow all currents measured along the Chukchi coast were toward the NE. Current directions along the Beaufort coast in the nearshore region were generally parallel to the coast, with 45% of the observations indicating currents toward the E and 55% currents toward the W.

  12. The multi-axis vibration environment and man.

    PubMed

    Lovesey, E J

    1970-12-01

    Many investigations into the effects of vibration on man have been performed since Mallock's first study of London Underground vibrations in 1902. The vibration research has tended to be confined to the vertical (heave) axis, yet recent experiments have indicated that low frequency vibration along the lateral (sway) axis has a greater adverse effect upon comfort and performance. Measurements of the vibration environments in current forms of transport including motor vehicles, hovercraft and aircraft etc have shown that appreciable quantities of vibration along all three axes exist. Further vibration research should consider the effects of multi-axis vibrations upon man rather than limit tests to single axis vibration.

  13. Detecting defects in marine structures by using eddy current infrared thermography.

    PubMed

    Swiderski, W

    2016-12-01

    Eddy current infrared (IR) thermography is a new nondestructive testing (NDT) technique used for the detection of cracks in electroconductive materials. By combining the well-established inspection methods of eddy current NDT and IR thermography, this technique uses induced eddy currents to heat test samples. In this way, IR thermography allows the visualization of eddy current distribution that is distorted in defect sites. This paper discusses the results of numerical modeling of eddy current IR thermography procedures in application to marine structures.

  14. Targeting the IL-33/IL-13 Axis for Respiratory Viral Infections.

    PubMed

    Donovan, Chantal; Bourke, Jane E; Vlahos, Ross

    2016-04-01

    Lung diseases, such as asthma and chronic obstructive pulmonary disease (COPD), are highly prevalent worldwide. One of the major factors that limits the efficacy of current medication in these patients are viral infections, leading to exacerbations of symptoms and decreased quality of life. Current pharmacological strategies targeting virus-induced lung disease are problematic due to antiviral resistance and the requirement for strain-specific vaccination. Thus, new therapeutic strategies are urgently required. In this Opinion article, we provide state-of-the-art evidence from humans and preclinical animal models implicating the interleukin (IL)-33/IL-13 axis in virus-induced lung disease. Thus, targeting the IL-33/IL-13 axis may be a feasible way to overcome the limitations of current therapy used to treat virus-induced exacerbations of lung disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. The Bottlenose Dolphin (Tursiops truncatus) as a Model to Understand Variation in Stress and Reproductive Hormone Measures in Relation to Sampling Matrix, Demographics, and Environmental Factors

    DTIC Science & Technology

    2012-09-30

    and free- ranging individuals support the existence of these same stress response pathways in marine mammals. While the HPA axis and physiological ... aldosterone , thyroid and reproductive hormones) have been routinely measured in blood as part of the health assessment which also includes a complete...was developed during the workshop held in late-August. For all stress-related hormones (cortisol, aldosterone , T3, T4, and Free T4), correlational

  16. The Bottlenose Dolphin (Tursiops truncatus) as a Model to Understand Variation in Stress and Reproductive Hormone Measures in Relation to Sampling Matrix, Demographics, and Environmental Factors

    DTIC Science & Technology

    2012-09-30

    support the existence of these same stress response pathways in marine mammals. While the HPA axis and physiological processes driven by the GCs are...characterization of stress and stressors, provides unique opportunities to address questions related to stress. Serum hormones (cortisol, aldosterone , thyroid...during the workshop held in late-August. For all stress-related hormones (cortisol, aldosterone , T3, T4, and Free T4), correlational tests and

  17. Structural Acoustic UXO Detection and Identification in Marine Environments - Interim Report for SERDP MR-2103 Follow-On

    DTIC Science & Technology

    2015-07-30

    into the image processing algorithm the AUV position data available from the Doppler Velocity Log (DVL) and Inertial Measurement Unit ( IMU ) systems...uncertainty due to unknown sensor z coordinates. We considered both AUV altitude and roll but not pitch which we assumed to have a small effect on the...buried target. Taken together, the images suggest that the block is buried horizontally but rolled along its long axis ~80° such that the exposed large

  18. Application of a New Grain-Based Reconstruction Algorithm to Microtomography Images for Quantitative Characterization and Flow Modeling

    DTIC Science & Technology

    2008-06-01

    mapping the X-ray absorption through the sample. The amount of absorption depends on the chemical composition and structure of the material and the X...obtained by measuring the X-ray attenua- tion coefficients of the sample at different angles as the sample is rotated about the vertical axis. These... McMaster University, Hamilton, Ontario, Canada. Allen H. Reed is a geologist with the Naval Research Laboratory. His research interests are in marine

  19. ITAG: A fine-scale measurement platform to inform organismal response to a changing ocean

    NASA Astrophysics Data System (ADS)

    Katija, K.; Shorter, K. A.; Mooney, T. A.; Mann, D.; Wang, A. Z.; Sonnichsen, F. N.

    2016-02-01

    Soft-bodied marine invertebrates comprise a keystone component of ocean ecosystems, however we know little of their behaviors and physiological responses within their natural habitat. Quantifying ocean conditions and measuring an organisms' response to the physical environment is vital to understanding organismal responses to a changing ocean. However, we face technological limitations when attempting to quantify the physical and environmental conditions that organisms encounter at spatial and temporal scales of an individual organism. Here we describe a novel, eco-sensor tag (the ITAG) that has 3-axis accelerometer, 3-axis magnetometer, pressure, temperature, and light sensors. Current and future efforts involve miniaturizing and integrating O2 and salinity sensors to the ITAG. The tagging package is designed to be neutrally buoyant, and after a prescribed time, the electronics separate from a weighted base and floats to the surface. Tags were deployed on five jellyfish (Aurelia aurita) and eight squid (Loligo forbesi) in laboratory conditions for up to 24 hr. Using concurrent video and tag data, movement signatures for specific behaviors were identified. Based on these laboratory trials, we found that squid activity level changed in response to ambient light conditions, which can inform trade-offs between behavior and energy expenditure in captive and wild animals. The ITAG opens the door for lab and field-based measurements of behavior, physiology, and concurrent environmental parameters that not only inform interactions in a changing ocean, but also provides a novel platform by which characterization of the environment can be conducted at fine spatial and temporal scales.

  20. Variable-frequency synchronous motor drives for electric vehicles

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

    Chalmers, B.J.; Musaba, L.; Gosden, D.F.

    1996-07-01

    The performance capability envelope of a variable-frequency, permanent-magnet synchronous motor drive with field weakening is dependent upon the product of maximum current and direct-axis inductance. To obtain a performance characteristic suitable for a typical electric vehicle drive, in which short-term increase of current is applied, it is necessary to design an optimum value of direct-axis inductance. The paper presents an analysis of a hybrid motor design which uses a two-part rotor construction comprising a surface-magnet part and an axially laminated reluctance part. This arrangement combines the properties of all other types of synchronous motor and offers a greater choice ofmore » design variables. It is shown that the desired form of performance may be achieved when the high-inductance axis of the reluctance part is arranged to lead the magnet axis by 90{degree} (elec.).« less

  1. Variable-frequency synchronous motor drives for electric vehicles

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

    Chalmers, B.J.; Musaba, L.; Gosden, D.F.

    1995-12-31

    The performance capability envelope of a variable-frequency, permanent-magnet synchronous motor drive with field weakening is dependent upon the product of maximum current and direct-axis inductance. To obtain a performance characteristic suitable for a typical electric vehicle drive, in which short-term increase of current is applied, it is necessary to design an optimum value of direct-axis inductance. The paper presents an analysis of a hybrid motor design which uses a two-part rotor construction comprising a surface-magnet part and an axially-laminated reluctance part. This arrangement combines the properties of all other types of synchronous motor and offers a greater choice of designmore » variables. It is shown that the desired form of performance may be achieved when the high-inductance axis of the reluctance part is arranged to lead the magnet axis by 90{degree} (elec.).« less

  2. Ocean Data Interoperability Platform (ODIP): using regional data systems for global ocean research

    NASA Astrophysics Data System (ADS)

    Schaap, D.; Thijsse, P.; Glaves, H.

    2017-12-01

    Ocean acidification, loss of coral reefs, sustainable exploitation of the marine environment are just a few of the challenges researchers around the world are currently attempting to understand and address. However, studies of these ecosystem level challenges are impossible unless researchers can discover and re-use the large volumes of interoperable multidisciplinary data that are currently only accessible through regional and global data systems that serve discreet, and often discipline specific, user communities. The plethora of marine data systems currently in existence are also using different standards, technologies and best practices making re-use of the data problematic for those engaged in interdisciplinary marine research. The Ocean Data Interoperability Platform (ODIP) is responding to this growing demand for discoverable, accessible and reusable data by establishing the foundations for a common global framework for marine data management. But creation of such an infrastructure is a major undertaking, and one that needs to be achieved in part by establishing different levels of interoperability across existing regional and global marine e-infrastructures. Workshops organised by ODIP II facilitate dialogue between selected regional and global marine data systems in an effort to identify potential solutions that integrate these marine e-infrastructures. The outcomes of these discussions have formed the basis for a number of prototype development tasks that aim to demonstrate effective sharing of data across multiple data systems, and allow users to access data from more than one system through a single access point. The ODIP II project is currently developing four prototype solutions that are establishing interoperability between selected regional marine data management infrastructures in Europe, the USA, Canada and Australia, and with the global POGO, IODE Ocean Data Portal (ODP) and GEOSS systems. The potential impact of implementing these solutions for the individual marine data infrastructures is also being evaluated to determine both the technical and financial implications of their integration within existing systems. These impact assessments form part of the strategy to encourage wider adoption of the ODIP solutions and approach beyond the current scope of the project.

  3. A local-circulation model for Darrieus vertical-axis wind turbines

    NASA Astrophysics Data System (ADS)

    Masse, B.

    1986-04-01

    A new computational model for the aerodynamics of the vertical-axis wind turbine is presented. Based on the local-circulation method generalized for curved blades, combined with a wake model for the vertical-axis wind turbine, it differs markedly from current models based on variations in the streamtube momentum and vortex models using the lifting-line theory. A computer code has been developed to calculate the loads and performance of the Darrieus vertical-axis wind turbine. The results show good agreement with experimental data and compare well with other methods.

  4. From Discovery to Production: Biotechnology of Marine Fungi for the Production of New Antibiotics.

    PubMed

    Silber, Johanna; Kramer, Annemarie; Labes, Antje; Tasdemir, Deniz

    2016-07-21

    Filamentous fungi are well known for their capability of producing antibiotic natural products. Recent studies have demonstrated the potential of antimicrobials with vast chemodiversity from marine fungi. Development of such natural products into lead compounds requires sustainable supply. Marine biotechnology can significantly contribute to the production of new antibiotics at various levels of the process chain including discovery, production, downstream processing, and lead development. However, the number of biotechnological processes described for large-scale production from marine fungi is far from the sum of the newly-discovered natural antibiotics. Methods and technologies applied in marine fungal biotechnology largely derive from analogous terrestrial processes and rarely reflect the specific demands of the marine fungi. The current developments in metabolic engineering and marine microbiology are not yet transferred into processes, but offer numerous options for improvement of production processes and establishment of new process chains. This review summarises the current state in biotechnological production of marine fungal antibiotics and points out the enormous potential of biotechnology in all stages of the discovery-to-development pipeline. At the same time, the literature survey reveals that more biotechnology transfer and method developments are needed for a sustainable and innovative production of marine fungal antibiotics.

  5. Effects of pharmaceuticals and personal care products on marine organisms: from single-species studies to an ecosystem-based approach.

    PubMed

    Prichard, Emma; Granek, Elise F

    2016-11-01

    Pharmaceuticals and personal care products (PPCPs) are contaminants of emerging concern that are increasing in use and have demonstrated negative effects on aquatic organisms. There is a growing body of literature reporting the effects of PPCPs on freshwater organisms, but studies on the effects of PPCPs to marine and estuarine organisms are limited. Among effect studies, the vast majority examines subcellular or cellular effects, with far fewer studies examining organismal- and community-level effects. We reviewed the current published literature on marine and estuarine algae, invertebrates, fish, and mammals exposed to PPCPs, in order to expand upon current reviews. This paper builds on previous reviews of PPCP contamination in marine environments, filling prior literature gaps and adding consideration of ecosystem function and level of knowledge across marine habitat types. Finally, we reviewed and compiled data gaps suggested by current researchers and reviewers and propose a multi-level model to expand the focus of current PPCP research beyond laboratory studies. This model includes examination of direct ecological effects including food web and disease dynamics, biodiversity, community composition, and other ecosystem-level indicators of contaminant-driven change.

  6. Healthy and unhealthy dependence: implications for major depression.

    PubMed

    Schulte, Fiona S; Mongrain, Myriam; Flora, David B

    2008-09-01

    To examine the contribution of varying levels of dependency to Axis I and Axis II disorders, and to the recurrence of major depression in a graduate student sample diagnosed with a history of the disorder. At Time 1, participants were interviewed to confirm a current or past episode of major depression along with the presence of Axis II and other current or past Axis I disorders. Various measures of dependency were administered including the Depressive Experiences Questionnaire (DEQ; Blatt, D'Afflitti, & Quinlan, 1976), the 3-Vector Dependency Inventory (3VDI; Pincus & Gurtman, 1995), and the Personal Style Inventory (PSI; Robins et al., 1994). Participants were interviewed 20 months later to determine the recurrence of a depressive episode. A factor analysis conducted on scale scores for each dependency measure resulted in three factors labelled 'unhealthy', 'intermediate', and 'healthy' dependence. Controlling for history of major depression, structural equation modelling found 'unhealthy' dependence to be the only predictor of recurrences of major depression and Axis II disorders, while 'healthy' dependence was related to fewer depressive symptoms. These results have important implications for the conceptualization of the dependency construct.

  7. Molar axis estimation from computed tomography images.

    PubMed

    Dongxia Zhang; Yangzhou Gan; Zeyang Xia; Xinwen Zhou; Shoubin Liu; Jing Xiong; Guanglin Li

    2016-08-01

    Estimation of tooth axis is needed for some clinical dental treatment. Existing methods require to segment the tooth volume from Computed Tomography (CT) images, and then estimate the axis from the tooth volume. However, they may fail during estimating molar axis due to that the tooth segmentation from CT images is challenging and current segmentation methods may get poor segmentation results especially for these molars with angle which will result in the failure of axis estimation. To resolve this problem, this paper proposes a new method for molar axis estimation from CT images. The key innovation point is that: instead of estimating the 3D axis of each molar from the segmented volume, the method estimates the 3D axis from two projection images. The method includes three steps. (1) The 3D images of each molar are projected to two 2D image planes. (2) The molar contour are segmented and the contour's 2D axis are extracted in each 2D projection image. Principal Component Analysis (PCA) and a modified symmetry axis detection algorithm are employed to extract the 2D axis from the segmented molar contour. (3) A 3D molar axis is obtained by combining the two 2D axes. Experimental results verified that the proposed method was effective to estimate the axis of molar from CT images.

  8. Design and flight performance evaluation of the Mariners 6, 7, and 9 short-circuit current, open-circuit voltage transducers

    NASA Technical Reports Server (NTRS)

    Patterson, R. E.

    1973-01-01

    The purpose of the short-circuit voltage transducer is to provide engineering data to aid the evaluation of array performance during flight. The design, fabrication, calibration, and in-flight performance of the transducers onboard the Mariner 6, 7 and 9 spacecrafts are described. No significant differences were observed in the in-flight electrical performance of the three transducers. The transducers did experience significant losses due to coverslides or adhesive darkening, increased surface reflection, or spectral shifts within coverslide assembly. Mariner 6, 7 and 9 transducers showed non-cell current degradations of 3-1/2%, 3%, and 4%, respectively at Mars encounter and 6%, 3%, and 4-12%, respectively at end of mission. Mariner 9 solar Array Test 2 showed 3-12% current degradation while the transducer showed 4-12% degradation.

  9. ’Marine’ Character of the United States Marine Band

    DTIC Science & Technology

    2008-04-01

    Classical Music Hall ofFame on May 24, 1998.14 In celebration of 200 years of service to our country and the Corps, the Marine Band was received as the guest...Saxophones LJ Cellos iH Guitar i Y Bassoons H Harp y Vocalists 1 31 AppendixE Current U.S. Marine Band Fitness Report « z o t3 ill en U.S. Marine Band FITNESS

  10. Specimen banking of marine organisms in the United States: Current status and long-term prospective

    USGS Publications Warehouse

    Becker, P.R.; Wise, S.A.; Thorsteinson, L.; Koster, B.J.; Rowles, T.

    1997-01-01

    A major part of the activities conducted over the last decade by the National Biomonitoring Specimen Bank (NBSB) has involved the archival of marine specimens collected by ongoing environmental monitoring programs. These archived specimens include bivalves, marine sediments, and fish tissues collected by the National Status and Trends and the Exxon Valdez Oil Spill Damage Assessment programs, and marine mammal tissues collected by the Marine Mammal Health and Stranding Response Program and the Alaska Marine Mammal Tissue Archival Project. In addition to supporting these programs, the specimens have been used to investigate circumpolar patterns of chlorinated hydrocarbon concentrations, genetic separation of marine animal stocks, baseline levels of essential and nonessential elements in marine mammals, and the potential risk to human consumers in the Arctic from anthropogenic contaminants found in local subsistence foods. The NBSB specimens represent a resource that has the potential for addressing future issues of marine environmental quality and ecosystem changes through retrospective analysis; however, an ecosystem-based food web approach would maximize this potential. The current status of the NBSB activities related to the banking of marine organisms is presented and discussed, the long-term prospective of these activities is presented, and the importance of an ecosystem-based food web monitoring approach to the value of specimen banking is discussed.

  11. Marine Biomedicine

    ERIC Educational Resources Information Center

    Bang, Frederik B.

    1977-01-01

    Describes early scientific research involving marine invertebrate pathologic processes that may have led to new insights into human disease. Discussed are inquiries of Metchnikoff, Loeb, and Cantacuzene (immunolgic responses in sea stars, horseshoe crabs, and marine worms, respectively). Describes current research stemming from these early…

  12. Mariner 9 Solar Array Design, Manufacture, and Performance

    NASA Technical Reports Server (NTRS)

    Sequeira, E. A.

    1973-01-01

    The mission of Mariner 9, the first spacecraft to orbit another planet, was to make scientific observations of the surface of Mars. Throughout this unique mission, the Mariner 9 solar array successfully supported the power requirements of the spacecraft without experiencing anomalies. Basically, the design of the solar array was similar to those of Mariners 6 and 7; however, Mariner 9 had the additional flight operational requirement to perform in a Mars orbit environment mode. The array special tests provided information on the current-voltage characteristics and array space degradation. Tests indicated that total solar array current degradation was 3.5 percent, which could probably be attributed to the gradual degradation of the cover glass and/or the RTV 602 adhesive employed to cement the cover glass to the solar cell.

  13. Control System for Bearingless Motor-generator

    NASA Technical Reports Server (NTRS)

    Kascak, Peter E. (Inventor); Jansen, Ralph H. (Inventor); Dever, Timothy P. (Inventor)

    2008-01-01

    A control system for an electromagnetic rotary drive for bearingless motor-generators comprises a winding configuration comprising a plurality of individual pole pairs through which phase current flows, each phase current producing both a lateral force and a torque. A motor-generator comprises a stator, a rotor supported for movement relative to the stator, and a control system. The motor-generator comprises a winding configuration supported by the stator. The winding configuration comprises at least three pole pairs through which phase current flows resulting in three three-phase systems. Each phase system has a first rotor reference frame axis current that produces a levitating force with no average torque and a second rotor reference frame axis current that produces torque.

  14. RF current profile control studies in the alcator C-mod tokamak

    NASA Astrophysics Data System (ADS)

    Bonoli, P. T.; Porkolab, M.; Wukitch, S. J.; Bernabei, S.; Kaita, R.; Mikkelsen, D.; Phillips, C. K.; Schilling, G.

    1999-09-01

    Time dependent calculations of lower hybrid (LH) current profile control in Alcator C-Mod have been done using the TRANSP [1], FPPRF [2], and LSC [3] codes. Up to 3 MW of LH current drive power was applied in plasmas with high power ICRF minority heating (PICH=1.8-3 MW) and fast current ramp up. Using the experimentally measured temperature profiles, off-axis current generation resulted in nonmonotonic q-profiles with qmin~=1.6. Self-consistent effects of off-axis electron heating by the LH power were also included in the analysis and significant broadening of the electron temperature profile was found with qmin>~2 and a larger shear reversal radius.

  15. Control system for bearingless motor-generator

    NASA Technical Reports Server (NTRS)

    Jansen, Ralph H. (Inventor); Dever, Timothy P. (Inventor); Kascak, Peter E. (Inventor)

    2010-01-01

    A control system for an electromagnetic rotary drive for bearingless motor-generators comprises a winding configuration comprising a plurality of individual pole pairs through which phase current flows, each phase current producing both a lateral force and a torque. A motor-generator comprises a stator, a rotor supported for movement relative to the stator, and a control system. The motor-generator comprises a winding configuration supported by the stator. The winding configuration comprises at least three pole pairs through which phase current flows resulting in three three-phase systems. Each phase system has a first rotor reference frame axis current that produces a levitating force with no average torque and a second rotor reference frame axis current that produces torque.

  16. Effect of Relative Marker Movement on the Calculation of the Foot Torsion Axis Using a Combined Cardan Angle and Helical Axis Approach

    PubMed Central

    Graf, Eveline S.; Wright, Ian C.; Stefanyshyn, Darren J.

    2012-01-01

    The two main movements occurring between the forefoot and rearfoot segment of a human foot are flexion at the metatarsophalangeal joints and torsion in the midfoot. The location of the torsion axis within the foot is currently unknown. The purpose of this study was to develop a method based on Cardan angles and the finite helical axis approach to calculate the torsion axis without the effect of flexion. As the finite helical axis method is susceptible to error due to noise with small helical rotations, a minimal amount of rotation was defined in order to accurately determine the torsion axis location. Using simulation, the location of the axis based on data containing noise was compared to the axis location of data without noise with a one-sample t-test and Fisher's combined probability score. When using only data with helical rotation of seven degrees or more, the location of the torsion axis based on the data with noise was within 0.2 mm of the reference location. Therefore, the proposed method allowed an accurate calculation of the foot torsion axis location. PMID:22666303

  17. A Perspective on Pre-University and College Marine and Aquatic Education in Canada.

    ERIC Educational Resources Information Center

    Graham, Robert; And Others

    This paper: (1) reviews the goals and directions of United States marine education; (2) reports the findings of three surveys which were designed to provide a perspective on current Canadian efforts in marine education; and (3) presents a set of proposed goals and future directions for marine education in Canada. Federal agencies with a…

  18. Seismic anisotropy in the Earth's innermost inner core: Testing structural models against mineral physics predictions

    DOE PAGES

    Romanowicz, Barbara; Cao, Aimin; Godwal, Budhiram; ...

    2016-01-06

    Using an updated data set of ballistic PKIKP travel time data at antipodal distances, we test different models of anisotropy in the Earth's innermost inner core (IMIC) and obtain significantly better fits for a fast axis aligned with Earth's rotation axis, rather than a quasi-equatorial direction, as proposed recently. Reviewing recent results on the single crystal structure and elasticity of iron at core conditions, we find that an hcp structure with the fast c axis parallel to Earth's rotation is more likely but a body-centered cubic structure with the [111] axis aligned in that direction results in very similar predictionsmore » for seismic anisotropy. These models are therefore not distinguishable based on current seismological data. In addition, to match the seismological observations, the inferred strength of anisotropy in the IMIC (6–7%) implies almost perfect alignment of iron crystals, an intriguing, albeit unlikely situation, especially in the presence of heterogeneity, which calls for further studies. Fast axis of anisotropy in the central part of the inner core aligned with Earth's axis of rotation Lastly, the structure of iron in the inner core is most likely hcp, not bcc Not currently possible to distinguish between hcp and bcc structures from seismic observations« less

  19. Design and test of 1/5th scale horizontal axis tidal current turbine

    NASA Astrophysics Data System (ADS)

    Liu, Hong-wei; Zhou, Hong-bin; Lin, Yong-gang; Li, Wei; Gu, Hai-gang

    2016-06-01

    Tidal current energy is prominent and renewable. Great progress has been made in the exploitation technology of tidal current energy all over the world in recent years, and the large scale device has become the trend of tidal current turbine (TCT) for its economies. Instead of the similarity to the wind turbine, the tidal turbine has the characteristics of high hydrodynamic efficiency, big thrust, reliable sealing system, tight power transmission structure, etc. In this paper, a 1/5th scale horizontal axis tidal current turbine has been designed, manufactured and tested before the full scale device design. Firstly, the three-blade horizontal axis rotor was designed based on traditional blade element momentum theory and its hydrodynamic performance was predicted in numerical model. Then the power train system and stand-alone electrical control unit of tidal current turbine, whose performances were accessed through the bench test carried out in workshop, were designed and presented. Finally, offshore tests were carried out and the power performance of the rotor was obtained and compared with the published literatures, and the results showed that the power coefficient was satisfactory, which agrees with the theoretical predictions.

  20. Diatom assemblages as guides to flow conditions during the 2004 Indian Ocean tsunami at Phra Thong Island, Thailand

    NASA Astrophysics Data System (ADS)

    Sawai, Y.; Jankaew, K.; Martin, M. E.; Choowong, M.; Charoentitirat, T.; Prendergast, A.

    2008-12-01

    Diatom assemblages in the 2004 tsunami deposits of Phra Thong Island, Thailand represent flow conditions during the tsunami. The tsunami deposit consists of single or multiple graded beds. Diatom assemblages in the lowermost part of the deposit predominantly comprise beach and subtidal species. In the middle part of the deposit, the assemblages are dominated by marine plankton with increasing finer fractions. A mixed assemblage of freshwater, brackish, and marine species occupies the uppermost part of the deposit. Changes in flow conditions during the tsunami can explain these diatom assemblage variations. During fast current velocities, medium sand is deposited; only beach and subtidal diatoms that live attached to the sand can be incorporated into the tsunami deposit under these flow conditions. It is difficult for diatoms in suspension to settle out under fast current velocities. With decreasing current velocities, marine plankton can settle out of the water column .Finally, during the suspension stage (calm currents) between tsunami waves, the entrained freshwater, brackish, and marine species settle out with mud and plant trash. Fewer broken valves in the lowermost part of the deposit is probably a results of rapid entrainment, whilst selective breakage of marine plankton (Thalassionema nitzschioides, and Thalassiosira and Coscinodiscus spp.) in the middle part of the deposit probably results from abrasion by turbulent current before their deposition.

  1. The Evaluation and Utilization of Marine-derived Bioactive Compounds with Anti-obesity Effect.

    PubMed

    Jin, Qiu; Yu, Huahua; Li, Pengcheng

    2018-01-01

    Obesity is a global epidemic throughout the world. There is thus increasing interest in searching for natural bioactive compounds with anti-obesity effect. A number of marine compounds have been regarded as potential sources of bioactive compounds and are associated with an anti-obesity effect. Marine-derived compounds with anti-obesity effect and their current applications, methods and indicators for the evaluation of anti-obesity activity are summarized in this review. in order to make contributions to the development of marine-derived functional food against obesity. In this review, an overview of marine-derived compounds with anti-obesity effect, including marine polysaccharides, marine lipid, marine peptides, marine carotenoids is intensively made with an emphasis on their efficacy and mechanism of action. Meanwhile, methods and indicators for the evaluation of anti-obesity activity are discussed. We summarize these methods into three categories: in vitro assay (including adsorption experiments and enzyme inhibitory assay), cell line study, animal experiments and clinical experiments. In addition, a brief introduction of the current applications of marine bioactive compounds with anti-obesity activity is discussed. Marine environment is a rich source of both biological and chemical diversity. In the past decades, numerous novel compounds with anti-obesity activity have been obtained from marine organisms, and many of them have been applied to industrial production such as functional foods and pharmaceuticals. Further studies are needed to explore the above-mentioned facts. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  2. Motility of magnetotactic bacteria/MTB to Geomagnetic fields

    NASA Astrophysics Data System (ADS)

    Hidajatullah-Maksoed, Fatahillah

    2016-03-01

    Bacteria with motility directed by a local geomagnetic fields have been observed in marine sediments'' discussed by R. Blakemore, 1975. Magnetotactic bacteria/MTB discovered in 1963 by Salvatore Bellini. For ``off-axis electron holography in the transmission electron microscope was used to correlates the physical & magnetic microstructure of magnetite nanocrystals in magnetotactic bacteria'' sought ``single-domain magnetite in hemopelagic sediments'' from JF Stolz. Otherwise, for potential source of bioproducts- product meant from result to multiplier -of magnetotactic bacteria[ACV Araujo, et.al, 2014 ] of marine drugs retrieved the `measurement of cellular chemotaxis with ECIS/Taxis, from KM Pietrosimone, 2012, whereas after ``earth magnetic field role on small living models'' are other interpretation of ``taxis'' as a movement of a cell instead usual ``tax'' for yew's taxus cuspidate, hired car & taxes in financial realms. Acknowledgements to HE. Mr. H. TUK SETYOHADI, Jl. Sriwijaya Raya 3, South-Jakarta, INDONESIA.

  3. In situ measurements of wind and current speed and relationship between output power and turbulence

    NASA Astrophysics Data System (ADS)

    Duran Medina, Olmo; Schmitt, François G.; Sentchev, Alexei; Calif, Rudy

    2015-04-01

    In a context of energy transition, wind and tidal energy are sources of clean energy with the potential of partially satisfying the growing demand. The main problem of this type of energy, and other types of renewable energy remains the discontinuity of the electric power produced in different scales, inducing large fluctuations also called intermittency. This intermittency of wind and tidal energy is inherent to the turbulent nature of wind and marine currents. We consider this intermittent power production in strong relation with the turbulent intermittency of the resource. The turbulence theory is multifractal energy cascades models, a classic in physics of turbulence. From earlier studies in atmospheric sciences, we learn that wind speed and the aggregate power output are intermittent and multifractal over a wide range of scales [Calif and Schmitt 2014]. We want to extend this study to a marine current turbine and compare the scaling properties for those renewable energy sources. We consider here coupling between simultaneous velocity time series and output power from a wind turbine and a marine current turbine. Wind turbine data were obtained from Denmark and marine current data from Western Scheldt, Belgium where a prototype of a vertical and horizontal marine current turbines are tested. After an estimation of their Fourier density power spectra, we study their scaling properties in Kolmogorov's theory and the framework of fully developed turbulence. Hence, we employ a Hilbert-based methodology, namely arbitrary-order Hilbert spectral analysis [Calif et al. 2013a, 2013b] to characterize the intermittent property of the wind and marine current velocity in order to characterize the intermittent nature of the fluid. This method is used in order to obtain the spectrum and the corresponding power law for non-linear and non-stationary time series. The goal is to study the non-linear transfer characteristics in a multi-scale and multi-intensity framework.

  4. The Effect of Sn Orientation on Intermetallic Compound Growth in Idealized Sn-Cu-Ag Interconnects

    NASA Astrophysics Data System (ADS)

    Kinney, Chris; Linares, Xioranny; Lee, Kyu-Oh; Morris, J. W.

    2013-04-01

    The work reported here explores the influence of crystal orientation on the growth of the interfacial intermetallic layer during electromigration in Cu||Sn||Cu solder joints. The samples were thin, planar Sn-Ag-Cu (SAC) solder layers between Cu bars subject to a uniaxial current. Electron backscatter diffraction (EBSD) was used to characterize the microstructure before and after testing. The most useful representation of the EBSD data identifies the Sn grain orientation by the angle between the Sn c-axis and the current direction. The tested samples included single-crystal joints with c-axis nearly parallel to the current ("green" samples) and with c-axis perpendicular to the current ("red" samples). At current density of 104 A/cm2 (steady-state temperature of ~150°C), an intermetallic layer grew at an observable rate in the "green" samples, but not in the "red" ones. A current density of 1.15 × 104 A/cm2 (temperature ~160°C) led to measurable intermetallic growth in both samples. The growth fronts were nearly planar and the growth rates constant (after an initial incubation period); the growth rates in the "green" samples were about 10× those in the "red" samples. The Cu concentrations were constant within the joints, showing that the intermetallic growth is dominated by the electromigration flux. The measured growth rates and literature values for the diffusion of Cu in Sn were used to extract values for the effective charge, z *, that governs the electromigration of Cu. The calculated value of z * is significantly larger for current perpendicular to the c-axis than along it.

  5. Psychiatric morbidity in murder and attempted murder crime convicts: a Turkey study.

    PubMed

    Kugu, N; Akyuz, G; Dogan, O

    2008-03-05

    In the present, the morbidity of psychiatric disorders of homicide/attempted homicide crime convicts imprisoned in Turkey, Sivas maximum security prison was investigated. Seventy imprisoned homicide/attempted homicide crime convicts included in this study. Sociodemographic information form, structured clinical interview for DSM-IV Axis-I disorders and structured clinical interview for DSM-III-R personality disorders applied to the participants. Most commonly diagnosed disorders among those convicts were current Axis-I disorders, depressive disorders (7.1%) and anxiety disorders (5.7%). Among Axis-I disorders, the most diagnosed one was the substance use disorders (45.7%). The most diagnosed Axis-II disorder was found as to be antisocial personality disorder (48.6%). The rate of convicts who were diagnosed as having both Axis-I and Axis-II disorders was 51.4%. The most prevalently accompanying lifetime Axis-I disorders to antisocial personality disorder with respect to Axis-I, and Axis-II comorbidity was substance use disorders. As a result, it was thought that the substance use disorders and antisocial personality disorder among the homicide/attempted homicide crime convicts were the most prevalent lifetime psychiatric disorders.

  6. Marine mammal harvests and other interactions with humans.

    PubMed

    Hovelsrud, Grete K; McKenna, Meghan; Huntington, Henry P

    2008-03-01

    The Arctic is currently undergoing rapid social and environmental changes, and while the peoples of the north have a long history of adapting, the current changes in climate pose unprecedented challenges to the marine mammal-human interactions in the Arctic regions. Arctic marine mammals have been and remain an important resource for many of the indigenous and nonindigenous people of the north. Changes in climate are likely to bring about profound changes to the environment in which these animals live and subsequently to the hunting practices and livelihoods of the people who hunt them. Climate change will lead to reduction in the sea ice extent and thickness and will likely increase shipping through the Northern Sea Route and the Northwest Passage and oil and gas activities in Arctic areas previously inaccessible. Such activities will lead to more frequent interactions between humans and marine mammals. These activities may also change the distribution of marine mammals, affecting the hunters. This paper has three parts. First, an overview of marine mammal harvesting activities in the different circumpolar regions provides a snapshot of current practices and conditions. Second, case studies of selected Arctic regions, indigenous groups, and species provide insight into the manner in which climate change is already impacting marine mammal harvesting activities in the Arctic. Third, we describe how climate change is likely to affect shipping and oil and gas exploration and production activities in the Arctic and describe the possible implications of these changes for the marine mammal populations. We conclude that many of the consequences of climate change are likely to be negative for marine mammal hunters and for marine mammals. Lack of adequate baseline data, however, makes it difficult to identify specific causal mechanisms and thus to develop appropriate conservation measures. Nonetheless, the future of Arctic marine mammals and human uses of them depends on addressing this challenge successfully.

  7. THE VERTICAL PLANAR MOTION MECHANISM; A DYNAMIC TEST APPARATUS FOR EVALUATING CURRENT METERS AND OTHER MARINE INSTRUMENTATION

    EPA Science Inventory

    The overall objective was to provide a dynamic test apparatus that can produce known, controlled high frequency dynamics for the evaluation of current meters and other marine instrumentation. Of primary interest is the establishment of flow sensor measurement capabilities, and he...

  8. A Statistically Based Training Diagnostic Tool for Marine Aviation

    DTIC Science & Technology

    2014-06-01

    mission essential task list MDG maneuver description guide MOS military occupational specialty MSHARP Marine Sierra Hotel Aviation Reporting Program...include the Defense Readiness Reporting System (DRRS) Marine Corps, the Current Readiness Program (CRP), and the Marine Sierra Hotel Aviation...Beuschel, 2008). Many of these systems focus on business decisions regarding how companies can increase their bottom line, by appealing to customers more

  9. A proposal for a new multiaxial model of psychiatric diagnosis. A continuum-based patient model derived from evolutionary developmental gene-environment interaction.

    PubMed

    Leigh, Hoyle

    2009-01-01

    To review recent genetic and neuroscientific research on psychiatric syndromes based on the current diagnostic scheme, and develop a better-fitting multiaxial patient-oriented diagnostic model. DSM I, published in 1952, considered psychiatric illnesses as reactions or extremes of adaptations of the patient's personality to stressful environmental demands. Personality itself was determined by constitution and psychodynamic development. In 1980, this continuum model gave way to an atheoretical categorical diagnostic scheme (DSM III), based on research diagnostic criteria for obtaining 'pure cultures' of patients for biological research. Subsequent research using the 'pure cultures' suggests that psychiatric syndromes represent a phenotypic continuum determined by genes, childhood traumas, and recent stress, mitigated by childhood nurturance, education, and current social support. Specific gene x childhood abuse x recent stress interactions have been discovered, which may serve as a model of how interacting vulnerability genes may or may not result in a psychiatric syndrome, depending on the individual's developmental history and current stress. A continuum model is proposed, with genes interacting with early experiences of stress or nurturance resulting in brain states that may evince minor but persistent symptoms (neurosis) or maladaptive patterns of behavior (personality disorder). The addition of recent or current stress may precipitate a major psychiatric syndrome. While a severe genetic predisposition, such as a mutation, may be sufficient to cause a major syndrome, major psychiatric syndromes are best conceptualized as dysregulation of evolutionarily adaptive brain functions, such as anxiety and vigilance. A new multiaxial model of psychiatric diagnosis is proposed based on this model: axis I for phenomenological diagnoses that include major psychiatric syndromes (e.g. depressive syndrome, psychosis), neuroses, personality disorders, and isolated symptoms; axis II for geno-neuroscience diagnoses, some of which may represent biological conditions associated with axis I, i.e. genes, specific brain morphology, and the functional state of specific brain areas based on laboratory and imaging studies; axis III for medical diseases and conditions; axis IV for stress (childhood, recent, and current); axis V for psychosocial assets (intelligence, education, school/work, social support, and global assessment of functioning) over past 5 years and current. (c) 2008 S. Karger AG, Basel.

  10. Teaching marine science to the next generation: Innovative programs for 6th”8th Graders gain momentum

    NASA Astrophysics Data System (ADS)

    Tebbens, S. F.; Coble, P. G.; Greely, T.

    Three educational outreach programs designed for middle school students (grades 6, 7, and 8) by faculty at the University of South Florida (USF) Department of Marine Science are turning kids onto science. The programs are bringing marine science research and its various technologies into the classroom, where students follow up with hands-on activities. Project Oceanography (PO) is an interactive broadcast that exposes students to the concepts and tools of current marine science research. The Oceanography Camp for Girls (OCG) boosts girls' curiosity and interest in science and nature. And teachers become better equipped to present current marine science topics and technology to their students at the Teachers Oceanography Workshop (TOW). All of the programs created by USF are provided at no cost to students or their institutions.

  11. The high-βN hybrid scenario for ITER and FNSF steady-state missions

    DOE PAGES

    Turco, Francesca; Petty, Clinton C.; Luce, Timothy C.; ...

    2015-05-15

    New experiments on DIII-D have demonstrated the steady-state potential of the hybrid scenario, with 1 MA of plasma current driven fully non-inductively and βN up to 3.7 sustained for ~3 s (~1.5 current diffusion time, τ R, in DIII-D), providing the basis for an attractive option for steady-state operation in ITER and FNSF. Excellent confinement is achieved (H 98y2~1.6) without performance limiting tearing modes. Furthermore, the hybrid regime overcomes the need for off-axis current drive efficiency, taking advantage of poloidal magnetic flux pumping that is believed to be the result of a saturated 3/2 tearing mode. This allows for efficientmore » current drive close to the axis, without deleterious sawtooth instabilities. In these experiments, the edge surface loop voltage is driven down to zero for >1 τ R when the poloidal β is increased above 1.9 at a plasma current of 1.0 MA and the ECH power is increased to 3.2 MW. Stationary operation of hybrid plasmas with all on-axis current drive is sustained at pressures slightly above the ideal no-wall limit, while the calculated ideal with-wall MHD limit is β N~4-4.5. Off-axis NBI power has been used to broaden the pressure and current profiles in this scenario, seeking to take advantage of higher predicted kink stability limits and lower values of the tearing stability index Δ', as calculated by the DCON and PEST3 codes. Our results are based on measured profiles that predict ideal limits at βN>4.5, 10% higher than the cases with on-axis NBI. A 0-D model, based on the present confinement, βN and shape values of the DIII-D hybrid scenario, shows that these plasmas are consistent with the ITER 9 MA, Q=5 mission and the FNSF 6.7 MA scenario with Q=3.5. With collisionality and edge safety factor values comparable to those envisioned for ITER and FNSF, the high-βN hybrid represents an attractive high performance option for the steady-state missions of these devices.« less

  12. From Discovery to Production: Biotechnology of Marine Fungi for the Production of New Antibiotics

    PubMed Central

    Silber, Johanna; Kramer, Annemarie; Labes, Antje; Tasdemir, Deniz

    2016-01-01

    Filamentous fungi are well known for their capability of producing antibiotic natural products. Recent studies have demonstrated the potential of antimicrobials with vast chemodiversity from marine fungi. Development of such natural products into lead compounds requires sustainable supply. Marine biotechnology can significantly contribute to the production of new antibiotics at various levels of the process chain including discovery, production, downstream processing, and lead development. However, the number of biotechnological processes described for large-scale production from marine fungi is far from the sum of the newly-discovered natural antibiotics. Methods and technologies applied in marine fungal biotechnology largely derive from analogous terrestrial processes and rarely reflect the specific demands of the marine fungi. The current developments in metabolic engineering and marine microbiology are not yet transferred into processes, but offer numerous options for improvement of production processes and establishment of new process chains. This review summarises the current state in biotechnological production of marine fungal antibiotics and points out the enormous potential of biotechnology in all stages of the discovery-to-development pipeline. At the same time, the literature survey reveals that more biotechnology transfer and method developments are needed for a sustainable and innovative production of marine fungal antibiotics. PMID:27455283

  13. Integrating Climate Change Resilience Features into the Incremental Refinement of an Existing Marine Park

    PubMed Central

    Beckley, Lynnath E.; Kobryn, Halina T.; Lombard, Amanda T.; Radford, Ben; Heyward, Andrew

    2016-01-01

    Marine protected area (MPA) designs are likely to require iterative refinement as new knowledge is gained. In particular, there is an increasing need to consider the effects of climate change, especially the ability of ecosystems to resist and/or recover from climate-related disturbances, within the MPA planning process. However, there has been limited research addressing the incorporation of climate change resilience into MPA design. This study used Marxan conservation planning software with fine-scale shallow water (<20 m) bathymetry and habitat maps, models of major benthic communities for deeper water, and comprehensive human use information from Ningaloo Marine Park in Western Australia to identify climate change resilience features to integrate into the incremental refinement of the marine park. The study assessed the representation of benthic habitats within the current marine park zones, identified priority areas of high resilience for inclusion within no-take zones and examined if any iterative refinements to the current no-take zones are necessary. Of the 65 habitat classes, 16 did not meet representation targets within the current no-take zones, most of which were in deeper offshore waters. These deeper areas also demonstrated the highest resilience values and, as such, Marxan outputs suggested minor increases to the current no-take zones in the deeper offshore areas. This work demonstrates that inclusion of fine-scale climate change resilience features within the design process for MPAs is feasible, and can be applied to future marine spatial planning practices globally. PMID:27529820

  14. Acquisition of Ice-Tethered Profilers with Velocity (ITP-V) Instruments for Future Arctic Studies

    DTIC Science & Technology

    2016-11-15

    instrument that measures sea water temperature and salinity versus depth, the ITP-V adds a multi-axis acoustic -travel-time current meter and...housing capped by an ultra-high-molecular-weight polyethylene dome. The electronics case sits within a foam body designed to provide buoyancy for...then transmits them by satellite to a logger computer at WHO I. The ITP-V instruments add a multi-axis acoustic -travel-time current meter and

  15. 75 FR 20032 - Information Collection Available for Public Comments and Recommendations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-16

    ... Underwriters of Marine Hull Insurance. Type of Request: Extension of currently approved information collection... collection of information involves the approval of marine hull underwriters to insure Maritime Administration... suitability for providing marine hull insurance on Maritime Administration vessels. Description of Respondents...

  16. 77 FR 14348 - Proposed Information Collection; Comment Request; Marine Recreational Information Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-09

    ... Collection; Comment Request; Marine Recreational Information Program AGENCY: National Oceanic and Atmospheric... for revision of a current information collection. Marine recreational anglers are surveyed to collect catch and effort data, fish biology data, and angler socioeconomic characteristics. These data are...

  17. The Source Book of Marine Sciences.

    ERIC Educational Resources Information Center

    Bergen, Bob; And Others

    Intended primarily for the secondary level, this manual presents 35 laboratory and field activities in marine science. Also included are chapters which cover field trip logistics, marine science centers, films, and reference materials. Typical amonq the lessons are "Charting Local Current Systems,""Salinity,""Living World Within a…

  18. THE EVOLUTION OF THE ELECTRIC CURRENT DURING THE FORMATION AND ERUPTION OF ACTIVE-REGION FILAMENTS

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

    Wang, Jincheng; Yan, Xiaoli; Qu, Zhongquan

    We present a comprehensive study of the electric current related to the formation and eruption of active region filaments in NOAA AR 11884. The vertical current on the solar surface was investigated by using vector magnetograms (VMs) observed by HMI on board the Solar Dynamics Observatory. To obtain the electric current along the filament's axis, we reconstructed the magnetic fields above the photosphere by using nonlinear force-free field extrapolation based on photospheric VMs. Spatio-temporal evolutions of the vertical current on the photospheric surface and the horizontal current along the filament's axis were studied during the long-term evolution and eruption-related period,more » respectively. The results show that the vertical currents of the entire active region behaved with a decreasing trend and the magnetic fields also kept decreasing during the long-term evolution. For the eruption-related evolution, the mean transverse field strengths decreased before two eruptions and increased sharply after two eruptions in the vicinity of the polarity inversion lines underneath the filament. The related vertical current showed different behaviors in two of the eruptions. On the other hand, a very interesting feature was found: opposite horizontal currents with respect to the current of the filament's axis appeared and increased under the filament before the eruptions and disappeared after the eruptions. We suggest that these opposite currents were carried by the new flux emerging from the photosphere bottom and might be the trigger mechanism for these filament eruptions.« less

  19. Combination induction plasma tube and current concentrator for introducing a sample into a plasma

    DOEpatents

    Hull, Donald E.; Bieniewski, Thomas M.

    1988-01-01

    An induction plasma tube in combination with a current concentrator. The rent concentrator has a substantially cylindrical body having an open end and a partially closed end which defines an aperture. A first slot extends the longitudinal length of the cylindrical body and a second slot extends radially outward from the aperture. Together the first and second slots form a single L-shaped slot. The current concentrator is disposed within a volume bounded by an induction coil substantially along the axis thereof, and when power is applied to the induction coil a concentrated current is induced within the current concentrator aperture. The concentrator is moveable relative to the coil along the longitudinal axis of the coil to control the amount of current which is concentrated at the aperture.

  20. Study on off-axis detection of pulsed laser in atmosphere

    NASA Astrophysics Data System (ADS)

    Liang, Weiwei

    2018-02-01

    Laser communication, designation, and ranging are point to point and have a high degree of specificity, current laser detection, such as laser warning receiver system, could detect the scattering laser from the off-axis distance by scattering track on natural aerosols, which is helpful to locate the laser source. However, the intensity of the scattering laser is extremely weak and affected by many factors, in order to evaluate the detection characteristic, a simplified model of off-axis detection for scattering laser in the lower atmosphere based on the Mie scattering theory is presented in this paper, the performances of the off-axis laser detection in different conditions such as off-axis distance, visibility, incidence angle, and delay time are investigated.

  1. Marine current energy conversion: the dawn of a new era in electricity production.

    PubMed

    Bahaj, AbuBakr S

    2013-02-28

    Marine currents can carry large amounts of energy, largely driven by the tides, which are a consequence of the gravitational effects of the planetary motion of the Earth, the Moon and the Sun. Augmented flow velocities can be found where the underwater topography (bathymetry) in straits between islands and the mainland or in shallows around headlands plays a major role in enhancing the flow velocities, resulting in appreciable kinetic energy. At some of these sites where practical flows are more than 1 m s(-1), marine current energy conversion is considered to be economically viable. This study describes the salient issues related to the exploitation of marine currents for electricity production, resource assessment, the conversion technologies and the status of leading projects in the field. This study also summarizes important issues related to site development and some of the approaches currently being undertaken to inform device and array development. This study concludes that, given the highlighted commitments to establish favourable regulatory and incentive regimes as well as the aspiration for energy independence and combating climate change, the progress to multi-megawatt arrays will be much faster than that achieved for wind energy development.

  2. Three axis velocity probe system

    DOEpatents

    Fasching, George E.; Smith, Jr., Nelson S.; Utt, Carroll E.

    1992-01-01

    A three-axis velocity probe system for determining three-axis positional velocities of small particles in fluidized bed systems and similar applications. This system has a sensor head containing four closely-spaced sensing electrodes of small wires that have flat ends to establish a two axis plane, e.g. a X-Y plane. Two of the sensing electrodes are positioned along one of the axes and the other two are along the second axis. These four sensing electrodes are surrounded by a guard electrode, and the outer surface is a ground electrode and support member for the sensing head. The electrodes are excited by, for example, sinusoidal voltage having a peak-to-peak voltage of up to 500 volts at a frequency of 2 MHz. Capacitive currents flowing between the four sensing electrodes and the ground electrode are influenced by the presence and position of a particle passing the sensing head. Any changes in these currents due to the particle are amplified and synchronously detected to produce positional signal values that are converted to digital form. Using these digital forms and two values of time permit generation of values of the three components of the particle vector and thus the total velocity vector.

  3. Transverse beam motion on the second axis of the dual axis radiographic hydrodynamic test facility

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

    Caporaso, G J; Chen, Y J; Fawley, W M

    1999-03-23

    The accelerator on the second-axis of the Dual-Axis Radiographic Hydrodynamic Test (DARHT-II) facility will generate a 20 MeV, 2-4 kA, 2 µs long electron beam with an energy variation {<=} ± 0.5%. Four short current pulses with various lengths will be selected out of this 2 µs long current pulse and delivered to an x-ray converter target. The DARHT-II radiographic resolution requires these electron pulses to be focused to sub-millimeter spots on Bremsstrahlung targets with peak-to-peak transverse beam motion less than a few hundred microns. We have modeled the transverse beam motion, including the beam breakup instability, corkscrew motion, transversemore » resistive wall instability and beam induced transverse deflection in the kicker system, from the DARHT-II injector exit to the x-ray converter target. Simulations show that the transverse motion at the x-ray converters satisfies the DARHT-II radiographic requirements.« less

  4. Acoustically-equipped Ocean Gliders for Environmental and Oceanographic Research

    DTIC Science & Technology

    2014-09-30

    mammal occurrence and behavior. The instruments purchased with this grant will significantly enhance our DoD-funded work, including both currently...funded research and proposed research. OBJECTIVES The Navy observes and studies marine mammals , both to better understand marine mammal ...occurrence and behavior and also to mitigate the deleterious effects of its operations on marine mammals . To facilitate acquisition of marine mammal data, we

  5. Superconducting magnetic coil

    DOEpatents

    Aized, Dawood; Schwall, Robert E.

    1999-06-22

    A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil.

  6. Superconducting magnetic coil

    DOEpatents

    Aized, Dawood; Schwall, Robert E.

    1996-06-11

    A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil.

  7. Florida Marine Education Resources Bibliography. Report Number 51, Florida Sea Grant College.

    ERIC Educational Resources Information Center

    Gordon, Marjorie R.; Bane, Leni L.

    This multidisciplinary, annotated bibliography is offered to K-12 teachers, other educators, librarians, concerned parents, and community leaders to simplify locating and acquiring marine education materials and infusing marine subjects into existing curricula. Included are printed materials currently available from commercial publishers,…

  8. The algorithm of central axis in surface reconstruction

    NASA Astrophysics Data System (ADS)

    Zhao, Bao Ping; Zhang, Zheng Mei; Cai Li, Ji; Sun, Da Ming; Cao, Hui Ying; Xing, Bao Liang

    2017-09-01

    Reverse engineering is an important technique means of product imitation and new product development. Its core technology -- surface reconstruction is the current research for scholars. In the various algorithms of surface reconstruction, using axis reconstruction is a kind of important method. For the various reconstruction, using medial axis algorithm was summarized, pointed out the problems existed in various methods, as well as the place needs to be improved. Also discussed the later surface reconstruction and development of axial direction.

  9. Battelle's Marine Research Laboratory, Sequim

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

    Becker, C.D.; Strand, J.A.

    Scientists at Battelle's Marine Research Laboratory (MRL) in Sequim, Washington study the effect of human activities on marine ecosystems, with emphasis on near shore and estuarine environments. The laboratory provides research and development assistance to industry and government agencies engaged in management of marine technologies, operation of coastal power utilities, protection of the marine environment, and related areas. This paper outlines and discusses the functions of Battelle's MRL, it's history, it's unique features, it's areas of expertise, it's current programs, and it's cooperating agencies.

  10. Power Projection: The Current and Future Relevance of the M1A1Tank to Marine Corps Capabilities

    DTIC Science & Technology

    2002-01-01

    Kenneth W. Estes, Marines under Armor : The Marine Corps and the Armored Fighting Vehicle, 1916-2000 (Annapolis, MD: Naval institute Press, 2000), 183...is the M2 heavy barrel machine gun that has been in the U.S. inventory for decades. It can be fired from under armor and has a range of 1800 meters...Accessed 9 January 2002. Estes, Kenneth W. Marines under Armor : The Marine Corps and the Armored Fighting Vehicle, 1916-2000. Annapolis, MD

  11. Microfabricated teeter-totter resonator

    DOEpatents

    Adkins, Douglas Ray; Heller, Edwin J.; Shul, Randy J.

    2004-11-23

    A microfabricated teeter-totter resonator comprises a frame, a paddle pivotably anchored to the frame by pivot arms that define an axis of rotation, a current conductor line on a surface of the paddle, means for applying a static magnetic field substantially perpendicular to the rotational axis and in the plane of the paddle, and means for energizing the current conductor line with an alternating current. A Lorentz force is generated by the interaction of the magnetic field with the current flowing in the conductor line, causing the paddle to oscillate about the axis of rotation. The teeter-totter resonator can be fabricated with micromachining techniques with materials used in the integrated circuits manufacturing industry. The microfabricated teeter-totter resonator has many varied applications, both as an actuation device and as a sensor. When used as a chemical sensor, a chemically sensitive coating can be disposed on one or both surfaces of the paddle to enhance the absorption of chemical analytes from a fluid stream. The resulting mass change can be detected as a change in the resonant frequency or phase of the oscillatory motion of the paddle.

  12. Quaternary uplift and tilting of Amorgos Island (southern Aegean) and the 1956 earthquake

    NASA Astrophysics Data System (ADS)

    Stiros, Stathis C.; Marangou, Lila; Arnold, Maurice

    1994-12-01

    Uplifted Pleistocene marine sediments, submerged ancient ruins and raised beaches confirm earlier views that the asymmetry of the relief of Amorgos Island (southern Aegean) testifies to a fault-bounded block uplifted and tilted along a SW-NE trending horizontal axis; the uplifted coast corresponds to a high-gradient slope controlled by an oblique master normal fault. Furthermore, geomorphic and biological evidence, radiometric data and comparison of aerial photographs indicates that the 1956 earthquake (Ms = 7.4) uplifted the footwall of this normal fault by about 30 cm.

  13. Glycobiology of Reproductive Processes in Marine Animals: The State of the Art

    PubMed Central

    Gallo, Alessandra; Costantini, Maria

    2012-01-01

    Glycobiology is the study of complex carbohydrates in biological systems and represents a developing field of science that has made huge advances in the last half century. In fact, it combines all branches of biomedical research, revealing the vast and diverse forms of carbohydrate structures that exist in nature. Advances in structure determination have enabled scientists to study the function of complex carbohydrates in more depth and to determine the role that they play in a wide range of biological processes. Glycobiology research in marine systems has primarily focused on reproduction, in particular for what concern the chemical communication between the gametes. The current status of marine glycobiology is primarily descriptive, devoted to characterizing marine glycoconjugates with potential biomedical and biotechnological applications. In this review, we describe the current status of the glycobiology in the reproductive processes from gametogenesis to fertilization and embryo development of marine animals. PMID:23247316

  14. Public health assessment for El Toro Marine Corps Air Station, Santa Ana, Orange County, California, Region 9. CERCLIS No. CA6170023208. Final report

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

    Not Available

    El Toro Marine Corps Air Station is in Orange County, California, near the city of Irvine. The Marine Corps established El Toro in 1943, and it currently serves as the center for marine aviation operations on the Pacific Coast. El Toro Marine Corps Air Station was proposed for listing on EPA's National Priorities List (NPL) in 1989 because past operations and disposal practices contaminated local groundwater. Agricultural farm workers and well operators are exposed to contaminants in groundwater through unintentional ingestion of contaminated groundwater, dermal contact with contaminated groundwater, and inhalation of aerosolized groundwater contaminants. Future exposure could occur throughmore » two potable water wells that are located 10 miles downgradient of the contaminant plume. At the current rate of contaminant migration, those wells will be affected in one and a half to five years.« less

  15. Improved multi-directional eddy current inspection test apparatus for detecting flaws in metal articles

    DOEpatents

    Nance, Roy A.; Hartley, William H.; Caffarel, Alfred J.

    1984-01-01

    Apparatus is described for detecting flaws in a tubular workpiece in a single scan. The coils of a dual coil bobbin eddy current inspection probe are wound at a 45.degree. angle to the transverse axis of the probe, one coil having an angular position about the axis about 90.degree. relative to the angular position of the other coil, and the angle of intersection of the planes containing the coils being about 60.degree..

  16. Three-axis orthogonal transceiver coil for eddy current sounding

    NASA Astrophysics Data System (ADS)

    Sukhanov, D.; Zavyalova, K.; Goncharik, M.

    2017-08-01

    We propose the new structure of three-axis transceiver magnetic-induction coil for eddy current probing. Due to the orientation of the coils, the direct signal from the transmitting coil to the receiving coil is minimized, which provided a high dynamic range. Sensitivity in all directions is provided by combining coils of different orientations. Numerical simulation and experimental studies of such a system have been carried out and confirmed the applicability of the proposed method and the mathematical model.

  17. THE LIMITED EFFECT OF COINCIDENT ORIENTATION ON THE CHOICE OF INTRINSIC AXIS (.).

    PubMed

    Li, Jing; Su, Wei

    2015-06-01

    The allocentric system computes and represents general object-to-object spatial relationships to provide a spatial frame of reference other than the egocentric system. The intrinsic frame-of-reference system theory, which suggests people learn the locations of objects based upon an intrinsic axis, is important in research about the allocentric system. The purpose of the current study was to determine whether the effect of coincident orientation on the choice of intrinsic axis was limited. Two groups of participants (24 men, 24 women; M age = 24 yr., SD = 2) encoded different spatial layouts in which the objects shared the coincident orientation of 315° and 225° separately at learning perspective (0°). The response pattern of partial-scene-recognition task following learning reflected different strategies for choosing the intrinsic axis under different conditions. Under the 315° object-orientation condition, the objects' coincident orientation was as important as the symmetric axis in the choice of the intrinsic axis. However, participants were more likely to choose the symmetric axis as the intrinsic axis under the 225° object-orientation condition. The results suggest the effect of coincident orientation on the choice of intrinsic axis is limited.

  18. Measurement of νμ and νe Events in an Off-Axis Horn-Focused Neutrino Beam

    NASA Astrophysics Data System (ADS)

    Adamson, P.; Aguilar-Arevalo, A. A.; Anderson, C. E.; Bazarko, A. O.; Bishai, M.; Brice, S. J.; Brown, B. C.; Bugel, L.; Cao, J.; Choudhary, B. C.; Coney, L.; Conrad, J. M.; Cox, D. C.; Curioni, A.; Djurcic, Z.; Finley, D. A.; Fleming, B. T.; Ford, R.; Gallagher, H. R.; Garcia, F. G.; Garvey, G. T.; Green, C.; Green, J. A.; Harris, D.; Hart, T. L.; Hawker, E.; Hylen, J.; Imlay, R.; Johnson, R. A.; Karagiorgi, G.; Kasper, P.; Katori, T.; Kobilarcik, T.; Kopp, S.; Kourbanis, I.; Koutsoliotas, S.; Laird, E. M.; Linden, S. K.; Link, J. M.; Liu, Y.; Liu, Y.; Loiacono, L.; Louis, W. C.; Marchionni, A.; Mahn, K. B. M.; Marsh, W.; McGregor, G.; Messier, M. D.; Metcalf, W.; Meyers, P. D.; Mills, F.; Mills, G. B.; Monroe, J.; Moore, C. D.; Nelson, J. K.; Nelson, R. H.; Nguyen, V. T.; Nienaber, P.; Nowak, J. A.; Ouedraogo, S.; Patterson, R. B.; Pavlovic, Z.; Perevalov, D.; Polly, C. C.; Prebys, E.; Raaf, J. L.; Ray, H.; Roe, B. P.; Russell, A. D.; Sandberg, V.; Schirato, R.; Schmitz, D.; Shaevitz, M. H.; Shoemaker, F. C.; Smart, W.; Smith, D.; Sodeberg, M.; Sorel, M.; Spentzouris, P.; Stancu, I.; Stefanski, R. J.; Sung, M.; Tanaka, H. A.; Tayloe, R.; Tzanov, M.; Vahle, P.; van de Water, R.; Viren, B.; Wascko, M. O.; White, D. H.; Wilking, M. J.; Yang, H. J.; Yumiceva, F. X.; Zeller, G. P.; Zimmerman, E. D.; Zwaska, R.

    2009-05-01

    We report the first observation of off-axis neutrino interactions in the MiniBooNE detector from the NuMI beam line at Fermilab. The MiniBooNE detector is located 745 m from the NuMI production target, at 110 mrad angle (6.3°) with respect to the NuMI beam axis. Samples of charged-current quasielastic νμ and νe interactions are analyzed and found to be in agreement with expectation. This provides a direct verification of the expected pion and kaon contributions to the neutrino flux and validates the modeling of the NuMI off-axis beam.

  19. Interplay between low threshold voltage-gated K+ channels and synaptic inhibition in neurons of the chicken nucleus laminaris along its frequency axis

    PubMed Central

    Hamlet, William R.; Liu, Yu-Wei; Tang, Zheng-Quan; Lu, Yong

    2014-01-01

    Central auditory neurons that localize sound in horizontal space have specialized intrinsic and synaptic cellular mechanisms to tightly control the threshold and timing for action potential generation. However, the critical interplay between intrinsic voltage-gated conductances and extrinsic synaptic conductances in determining neuronal output are not well understood. In chicken, neurons in the nucleus laminaris (NL) encode sound location using interaural time difference (ITD) as a cue. Along the tonotopic axis of NL, there exist robust differences among low, middle, and high frequency (LF, MF, and HF, respectively) neurons in a variety of neuronal properties such as low threshold voltage-gated K+ (LTK) channels and depolarizing inhibition. This establishes NL as an ideal model to examine the interactions between LTK currents and synaptic inhibition across the tonotopic axis. Using whole-cell patch clamp recordings prepared from chicken embryos (E17–E18), we found that LTK currents were larger in MF and HF neurons than in LF neurons. Kinetic analysis revealed that LTK currents in MF neurons activated at lower voltages than in LF and HF neurons, whereas the inactivation of the currents was similar across the tonotopic axis. Surprisingly, blockade of LTK currents using dendrotoxin-I (DTX) tended to broaden the duration and increase the amplitude of the depolarizing inhibitory postsynaptic potentials (IPSPs) in NL neurons without dependence on coding frequency regions. Analyses of the effects of DTX on inhibitory postsynaptic currents led us to interpret this unexpected observation as a result of primarily postsynaptic effects of LTK currents on MF and HF neurons, and combined presynaptic and postsynaptic effects in LF neurons. Furthermore, DTX transferred subthreshold IPSPs to spikes. Taken together, the results suggest a critical role for LTK currents in regulating inhibitory synaptic strength in ITD-coding neurons at various frequencies. PMID:24904297

  20. Interplay between low threshold voltage-gated K(+) channels and synaptic inhibition in neurons of the chicken nucleus laminaris along its frequency axis.

    PubMed

    Hamlet, William R; Liu, Yu-Wei; Tang, Zheng-Quan; Lu, Yong

    2014-01-01

    Central auditory neurons that localize sound in horizontal space have specialized intrinsic and synaptic cellular mechanisms to tightly control the threshold and timing for action potential generation. However, the critical interplay between intrinsic voltage-gated conductances and extrinsic synaptic conductances in determining neuronal output are not well understood. In chicken, neurons in the nucleus laminaris (NL) encode sound location using interaural time difference (ITD) as a cue. Along the tonotopic axis of NL, there exist robust differences among low, middle, and high frequency (LF, MF, and HF, respectively) neurons in a variety of neuronal properties such as low threshold voltage-gated K(+) (LTK) channels and depolarizing inhibition. This establishes NL as an ideal model to examine the interactions between LTK currents and synaptic inhibition across the tonotopic axis. Using whole-cell patch clamp recordings prepared from chicken embryos (E17-E18), we found that LTK currents were larger in MF and HF neurons than in LF neurons. Kinetic analysis revealed that LTK currents in MF neurons activated at lower voltages than in LF and HF neurons, whereas the inactivation of the currents was similar across the tonotopic axis. Surprisingly, blockade of LTK currents using dendrotoxin-I (DTX) tended to broaden the duration and increase the amplitude of the depolarizing inhibitory postsynaptic potentials (IPSPs) in NL neurons without dependence on coding frequency regions. Analyses of the effects of DTX on inhibitory postsynaptic currents led us to interpret this unexpected observation as a result of primarily postsynaptic effects of LTK currents on MF and HF neurons, and combined presynaptic and postsynaptic effects in LF neurons. Furthermore, DTX transferred subthreshold IPSPs to spikes. Taken together, the results suggest a critical role for LTK currents in regulating inhibitory synaptic strength in ITD-coding neurons at various frequencies.

  1. The location of Airy-0, the Mars prime meridian reference, from stereo photogrammetric processing of THEMIS IR imaging and digital elevation data

    NASA Astrophysics Data System (ADS)

    Duxbury, T. C.; Christensen, P.; Smith, D. E.; Neumann, G. A.; Kirk, R. L.; Caplinger, M. A.; Albee, A. A.; Seregina, N. V.; Neukum, G.; Archinal, B. A.

    2014-12-01

    The small crater Airy-0 was selected from Mariner 9 images to be the reference for the Mars prime meridian. Initial analyses in the year 2000 tied Viking Orbiter and Mars Orbiter Camera images of Airy-0 to the evolving Mars Orbiter Laser Altimeter global digital terrain model to update the location of Airy-0. Based upon this tie and radiometric tracking of landers/rovers from Earth, new expressions for the Mars spin axis direction, spin rate, and prime meridian epoch value were produced to define the orientation of the Martian surface in inertial space over time. Since the Mars Global Surveyor mission and Mars Orbiter Laser Altimeter global digital terrain model were completed some time ago, a more exhaustive study has been performed to determine the accuracy of the Airy-0 location and orientation of Mars at the standard epoch. Thermal Emission Imaging System (THEMIS) IR image cubes of the Airy and Gale crater regions were tied to the global terrain grid using precision stereo photogrammetric image processing techniques. The Airy-0 location was determined to be about 0.001° east of its predicted location using the currently defined International Astronomical Union (IAU) prime meridian location. Information on this new location and how it was derived will be provided to the NASA Mars Exploration Program Geodesy and Cartography Working Group for their assessment. This NASA group will make a recommendation to the IAU Working Group on Cartographic Coordinates and Rotational Elements to update the expression for the Mars spin axis direction, spin rate, and prime meridian location.

  2. Tow tank measurements of turbulent flow in the near wake of a horizontal axis marine current turbine under steady and unsteady inflow conditions

    NASA Astrophysics Data System (ADS)

    Luznik, Luksa; van Benthem, Max; Flack, Karen; Lust, Ethan

    2013-11-01

    Near wake measurements are presented for a 0.8 m diameter (D) two bladed horizontal axis tidal turbine model for two inflow conditions. The first case had steady inflow conditions, i.e. turbine was towed at a constant carriage speed and the second case had a constant carriage speed and incoming regular waves with a period of 1.6 seconds and 0.09 m wave height. The test matrix in the wake covered four radial positions from r/D = 0.3 to 0.5 and five axial positions from x/D = 0.19 to 0.95. All measurements were performed at the nominal tip speed ratio (TSR) of 7.4. The distribution of mean velocities for the steady inflow case exhibit significant spatial variability in the wake region. Normalized mean streamwise velocity show a decrease in magnitude with the axial direction for all radial locations ranging from U/Utow = 0.55 at r/D = 0.49 to 0.35 at r/D = 0.3. Vertical and lateral mean velocities are small but consistent with counterclockwise fluid angular momentum for a clockwise rotor rotation. The Reynolds shear stresses consistently show elevated levels for measurements near the rotor tip (r/D = 0.49) and are significantly reduced by x/D = 0.6 downstream. This suggests low turbulence levels in the wake which is consistent with very low free stream turbulence. For the case with waves, evidence of enhanced turbulence intensities and shear stresses within spatial coverage of the experiment suggest increased in localized turbulence production in the blade tip region over the entire near wake region.

  3. Molecular profiling of marine fauna: integration of omics with environmental assessment of the world's oceans.

    PubMed

    Veldhoen, Nik; Ikonomou, Michael G; Helbing, Caren C

    2012-02-01

    Many species that contribute to the commercial and ecological richness of our marine ecosystems are harbingers of environmental change. The ability of organisms to rapidly detect and respond to changes in the surrounding environment represents the foundation for application of molecular profiling technologies towards marine sentinel species in an attempt to identify signature profiles that may reside within the transcriptome, proteome, or metabolome and that are indicative of a particular environmental exposure event. The current review highlights recent examples of the biological information obtained for marine sentinel teleosts, mammals, and invertebrates. While in its infancy, such basal information can provide a systems biology framework in the detection and evaluation of environmental chemical contaminant effects on marine fauna. Repeated evaluation across different seasons and local marine environs will lead to discrimination between signature profiles representing normal variation within the complex milieu of environmental factors that trigger biological response in a given sentinel species and permit a greater understanding of normal versus anthropogenic-associated modulation of biological pathways, which prove detrimental to marine fauna. It is anticipated that incorporation of contaminant-specific molecular signatures into current risk assessment paradigms will lead to enhanced wildlife management strategies that minimize the impacts of our industrialized society on marine ecosystems. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. Current and potential uses of bioactive molecules from marine processing waste.

    PubMed

    Suleria, Hafiz Ansar Rasul; Masci, Paul; Gobe, Glenda; Osborne, Simone

    2016-03-15

    Food industries produce huge amounts of processing waste that are often disposed of incurring expenses and impacting upon the environment. For these and other reasons, food processing waste streams, in particular marine processing waste streams, are gaining popularity amongst pharmaceutical, cosmetic and nutraceutical industries as sources of bioactive molecules. In the last 30 years, there has been a gradual increase in processed marine products with a concomitant increase in waste streams that include viscera, heads, skins, fins, bones, trimmings and shellfish waste. In 2010, these waste streams equated to approximately 24 million tonnes of mostly unused resources. Marine processing waste streams not only represent an abundant resource, they are also enriched with structurally diverse molecules that possess a broad panel of bioactivities including anti-oxidant, anti-coagulant, anti-thrombotic, anti-cancer and immune-stimulatory activities. Retrieval and characterisation of bioactive molecules from marine processing waste also contributes valuable information to the vast field of marine natural product discovery. This review summarises the current use of bioactive molecules from marine processing waste in different products and industries. Moreover, this review summarises new research into processing waste streams and the potential for adoption by industries in the creation of new products containing marine processing waste bioactives. © 2015 Society of Chemical Industry.

  5. Saturn Ring

    NASA Image and Video Library

    2007-12-12

    Like Earth, Saturn has an invisible ring of energetic ions trapped in its magnetic field. This feature is known as a "ring current." This ring current has been imaged with a special camera on Cassini sensitive to energetic neutral atoms. This is a false color map of the intensity of the energetic neutral atoms emitted from the ring current through a processed called charged exchange. In this process a trapped energetic ion steals and electron from cold gas atoms and becomes neutral and escapes the magnetic field. The Cassini Magnetospheric Imaging Instrument's ion and neutral camera records the intensity of the escaping particles, which provides a map of the ring current. In this image, the colors represent the intensity of the neutral emission, which is a reflection of the trapped ions. This "ring" is much farther from Saturn (roughly five times farther) than Saturn's famous icy rings. Red in the image represents the higher intensity of the particles, while blue is less intense. Saturn's ring current had not been mapped before on a global scale, only "snippets" or areas were mapped previously but not in this detail. This instrument allows scientists to produce movies (see PIA10083) that show how this ring changes over time. These movies reveal a dynamic system, which is usually not as uniform as depicted in this image. The ring current is doughnut shaped but in some instances it appears as if someone took a bite out of it. This image was obtained on March 19, 2007, at a latitude of about 54.5 degrees and radial distance 1.5 million kilometres (920,000 miles). Saturn is at the center, and the dotted circles represent the orbits of the moon's Rhea and Titan. The Z axis points parallel to Saturn's spin axis, the X axis points roughly sunward in the sun-spin axis plane, and the Y axis completes the system, pointing roughly toward dusk. The ion and neutral camera's field of view is marked by the white line and accounts for the cut-off of the image on the left. The image is an average of the activity over a (roughly) 3-hour period. http://photojournal.jpl.nasa.gov/catalog/PIA10094

  6. Rapid fabrication of miniature lens arrays by four-axis single point diamond machining

    PubMed Central

    McCall, Brian; Tkaczyk, Tomasz S.

    2013-01-01

    A novel method for fabricating lens arrays and other non-rotationally symmetric free-form optics is presented. This is a diamond machining technique using 4 controlled axes of motion – X, Y, Z, and C. As in 3-axis diamond micro-milling, a diamond ball endmill is mounted to the work spindle of a 4-axis ultra-precision computer numerical control (CNC) machine. Unlike 3-axis micro-milling, the C-axis is used to hold the cutting edge of the tool in contact with the lens surface for the entire cut. This allows the feed rates to be doubled compared to the current state of the art of micro-milling while producing an optically smooth surface with very low surface form error and exceptionally low radius error. PMID:23481813

  7. Field Balancing of Magnetically Levitated Rotors without Trial Weights

    PubMed Central

    Fang, Jiancheng; Wang, Yingguang; Han, Bangcheng; Zheng, Shiqiang

    2013-01-01

    Unbalance in magnetically levitated rotor (MLR) can cause undesirable synchronous vibrations and lead to the saturation of the magnetic actuator. Dynamic balancing is an important way to solve these problems. However, the traditional balancing methods, using rotor displacement to estimate a rotor's unbalance, requiring several trial-runs, are neither precise nor efficient. This paper presents a new balancing method for an MLR without trial weights. In this method, the rotor is forced to rotate around its geometric axis. The coil currents of magnetic bearing, rather than rotor displacement, are employed to calculate the correction masses. This method provides two benefits when the MLR's rotation axis coincides with the geometric axis: one is that unbalanced centrifugal force/torque equals the synchronous magnetic force/torque, and the other is that the magnetic force is proportional to the control current. These make calculation of the correction masses by measuring coil current with only a single start-up precise. An unbalance compensation control (UCC) method, using a general band-pass filter (GPF) to make the MLR spin around its geometric axis is also discussed. Experimental results show that the novel balancing method can remove more than 92.7% of the rotor unbalance and a balancing accuracy of 0.024 g mm kg−1 is achieved.

  8. Trak Investigation of Focusing Electrode Geometries for the DARHT Axis-I Diode

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

    Kallas, Nicholas Dimitrious

    2017-05-15

    An investigation was carried out on the effects of different cathode shroud geometries of the DARHT Axis-1 diode using the Trak ray tracing software. Pierce angles of 20, 30, 45, 60, and 67.5 degrees were investigated. For each geometry the current density with respect to radial position will be presented as it evolves in the longitudinal direction. In addition the emittances for each geometry are compared and this information is used to determine the optimal geometry from the selected angles. These results are compared to the baseline geometry currently employed at DARHT of a simple 2.5mm recessed velvet cathode. Ofmore » the selected angles it was found that 45 degrees produced the lowest normalized emittance value, whereas 60 degrees produced the most uniform current density profile at 1cm away from the emission surface. For the purpose of this investigation the effects of the bucking coil and solenoid around the hollow anode of the DARHT Axis I injector are neglected.« less

  9. Measurement of the inclusive νμ charged current cross section on iron and hydrocarbon in the T2K on-axis neutrino beam

    NASA Astrophysics Data System (ADS)

    Abe, K.; Adam, J.; Aihara, H.; Akiri, T.; Andreopoulos, C.; Aoki, S.; Ariga, A.; Assylbekov, S.; Autiero, D.; Barbi, M.; Barker, G. J.; Barr, G.; Bass, M.; Batkiewicz, M.; Bay, F.; Berardi, V.; Berger, B. E.; Berkman, S.; Bhadra, S.; Blaszczyk, F. d. M.; Blondel, A.; Bojechko, C.; Bordoni, S.; Boyd, S. B.; Brailsford, D.; Bravar, A.; Bronner, C.; Buchanan, N.; Calland, R. G.; Caravaca Rodríguez, J.; Cartwright, S. L.; Castillo, R.; Catanesi, M. G.; Cervera, A.; Cherdack, D.; Christodoulou, G.; Clifton, A.; Coleman, J.; Coleman, S. J.; Collazuol, G.; Connolly, K.; Cremonesi, L.; Dabrowska, A.; Danko, I.; Das, R.; Davis, S.; de Perio, P.; De Rosa, G.; Dealtry, T.; Dennis, S. R.; Densham, C.; Dewhurst, D.; Di Lodovico, F.; Di Luise, S.; Drapier, O.; Duboyski, T.; Duffy, K.; Dumarchez, J.; Dytman, S.; Dziewiecki, M.; Emery-Schrenk, S.; Ereditato, A.; Escudero, L.; Finch, A. J.; Friend, M.; Fujii, Y.; Fukuda, Y.; Furmanski, A. P.; Galymov, V.; Giffin, S.; Giganti, C.; Gilje, K.; Goeldi, D.; Golan, T.; Gonin, M.; Grant, N.; Gudin, D.; Hadley, D. R.; Haesler, A.; Haigh, M. D.; Hamilton, P.; Hansen, D.; Hara, T.; Hartz, M.; Hasegawa, T.; Hastings, N. C.; Hayato, Y.; Hearty, C.; Helmer, R. L.; Hierholzer, M.; Hignight, J.; Hillairet, A.; Himmel, A.; Hiraki, T.; Hirota, S.; Holeczek, J.; Horikawa, S.; Huang, K.; Ichikawa, A. K.; Ieki, K.; Ieva, M.; Ikeda, M.; Imber, J.; Insler, J.; Irvine, T. J.; Ishida, T.; Ishii, T.; Iwai, E.; Iwamoto, K.; Iyogi, K.; Izmaylov, A.; Jacob, A.; Jamieson, B.; Johnson, R. A.; Jo, J. H.; Jonsson, P.; Jung, C. K.; Kabirnezhad, M.; Kaboth, A. C.; Kajita, T.; Kakuno, H.; Kameda, J.; Kanazawa, Y.; Karlen, D.; Karpikov, I.; Katori, T.; Kearns, E.; Khabibullin, M.; Khotjantsev, A.; Kielczewska, D.; Kikawa, T.; Kilinski, A.; Kim, J.; Kisiel, J.; Kitching, P.; Kobayashi, T.; Koch, L.; Kolaceke, A.; Konaka, A.; Kormos, L. L.; Korzenev, A.; Koseki, K.; Koshio, Y.; Kreslo, I.; Kropp, W.; Kubo, H.; Kudenko, Y.; Kurjata, R.; Kutter, T.; Lagoda, J.; Laihem, K.; Lamont, I.; Larkin, E.; Laveder, M.; Lawe, M.; Lazos, M.; Lindner, T.; Lister, C.; Litchfield, R. P.; Longhin, A.; Ludovici, L.; Magaletti, L.; Mahn, K.; Malek, M.; Manly, S.; Marino, A. D.; Marteau, J.; Martin, J. F.; Martynenko, S.; Maruyama, T.; Matveev, V.; Mavrokoridis, K.; Mazzucato, E.; McCarthy, M.; McCauley, N.; McFarland, K. S.; McGrew, C.; Metelko, C.; Mijakowski, P.; Miller, C. A.; Minamino, A.; Mineev, O.; Missert, A.; Miura, M.; Moriyama, S.; Mueller, Th. A.; Murakami, A.; Murdoch, M.; Murphy, S.; Myslik, J.; Nakadaira, T.; Nakahata, M.; Nakamura, K.; Nakayama, S.; Nakaya, T.; Nakayoshi, K.; Nielsen, C.; Nirkko, M.; Nishikawa, K.; Nishimura, Y.; O'Keeffe, H. M.; Ohta, R.; Okumura, K.; Okusawa, T.; Oryszczak, W.; Oser, S. M.; Otani, M.; Owen, R. A.; Oyama, Y.; Palladino, V.; Palomino, J. L.; Paolone, V.; Payne, D.; Perevozchikov, O.; Perkin, J. D.; Petrov, Y.; Pickard, L.; Pinzon Guerra, E. S.; Pistillo, C.; Plonski, P.; Poplawska, E.; Popov, B.; Posiadala, M.; Poutissou, J.-M.; Poutissou, R.; Przewlocki, P.; Quilain, B.; Radicioni, E.; Ratoff, P. N.; Ravonel, M.; Rayner, M. A. M.; Redij, A.; Reeves, M.; Reinherz-Aronis, E.; Retiere, F.; Rodrigues, P. A.; Rojas, P.; Rondio, E.; Roth, S.; Rubbia, A.; Ruterbories, D.; Sacco, R.; Sakashita, K.; Sánchez, F.; Sato, F.; Scantamburlo, E.; Scholberg, K.; Schoppmann, S.; Schwehr, J.; Scott, M.; Seiya, Y.; Sekiguchi, T.; Sekiya, H.; Sgalaberna, D.; Shiozawa, M.; Short, S.; Shustrov, Y.; Sinclair, P.; Smith, B.; Smy, M.; Sobczyk, J. T.; Sobel, H.; Sorel, M.; Southwell, L.; Stamoulis, P.; Steinmann, J.; Still, B.; Suda, Y.; Suzuki, A.; Suzuki, K.; Suzuki, S. Y.; Suzuki, Y.; Szeglowski, T.; Tacik, R.; Tada, M.; Takahashi, S.; Takeda, A.; Takeuchi, Y.; Tanaka, H. K.; Tanaka, H. A.; Tanaka, M. M.; Terhorst, D.; Terri, R.; Thompson, L. F.; Thorley, A.; Tobayama, S.; Toki, W.; Tomura, T.; Totsuka, Y.; Touramanis, C.; Tsukamoto, T.; Tzanov, M.; Uchida, Y.; Vacheret, A.; Vagins, M.; Vasseur, G.; Wachala, T.; Waldron, A. V.; Walter, C. W.; Wark, D.; Wascko, M. O.; Weber, A.; Wendell, R.; Wilkes, R. J.; Wilking, M. J.; Wilkinson, C.; Williamson, Z.; Wilson, J. R.; Wilson, R. J.; Wongjirad, T.; Yamada, Y.; Yamamoto, K.; Yanagisawa, C.; Yano, T.; Yen, S.; Yershov, N.; Yokoyama, M.; Yuan, T.; Yu, M.; Zalewska, A.; Zalipska, J.; Zambelli, L.; Zaremba, K.; Ziembicki, M.; Zimmerman, E. D.; Zito, M.; Żmuda, J.; T2K Collaboration

    2014-09-01

    We report a measurement of the νμ inclusive charged current cross sections on iron and hydrocarbon in the Tokai-to-Kamioka (T2K) on-axis neutrino beam. The measured inclusive charged current cross sections on iron and hydrocarbon averaged over the T2K on-axis flux with a mean neutrino energy of 1.51 GeV are (1.444±0.002(stat)-0.157+0.189(syst))×10-38 cm2/nucleon and (1.379±0.009(stat)-0.147+0.178(syst))×10-38 cm2/nucleon, respectively, and their cross-section ratio is 1.047±0.007(stat)±0.035(syst). These results agree well with the predictions of the neutrino interaction model, and thus we checked the correct treatment of the nuclear effect for iron and hydrocarbon targets in the model within the measurement precisions.

  10. Current scaling of radiated power for 40-mm diameter single wire arrays on Z

    NASA Astrophysics Data System (ADS)

    Nash, T. J.; Cuneo, M. E.; Spielman, R. B.; Chandler, G. A.; Leeper, R. J.; Seaman, J. F.; McGurn, J.; Lazier, S.; Torres, J.; Jobe, D.; Gilliland, T.; Nielsen, D.; Hawn, R.; Bailey, J. E.; Lake, P.; Carlson, A. L.; Seamen, H.; Moore, T.; Smelser, R.; Pyle, J.; Wagoner, T. C.; LePell, P. D.; Deeney, C.; Douglas, M. R.; McDaniel, D.; Struve, K.; Mazarakis, M.; Stygar, W. A.

    2004-11-01

    In order to estimate the radiated power that can be expected from the next-generation Z-pinch driver such as ZR at 28 MA, current-scaling experiments have been conducted on the 20 MA driver Z. We report on the current scaling of single 40 mm diameter tungsten 240 wire arrays with a fixed 110 ns implosion time. The wire diameter is decreased in proportion to the load current. Reducing the charge voltage on the Marx banks reduces the load current. On one shot, firing only three of the four levels of the Z machine further reduced the load current. The radiated energy scaled as the current squared as expected but the radiated power scaled as the current to the 3.52±0.42 power due to increased x-ray pulse width at lower current. As the current is reduced, the rise time of the x-ray pulse increases and at the lowest current value of 10.4 MA, a shoulder appears on the leading edge of the x-ray pulse. In order to determine the nature of the plasma producing the leading edge of the x-ray pulse at low currents further shots were taken with an on-axis aperture to view on-axis precursor plasma. This aperture appeared to perturb the pinch in a favorable manner such that with the aperture in place there was no leading edge to the x-ray pulses at lower currents and the radiated power scaled as the current squared ±0.75. For a full-current shot we will present x-ray images that show precursor plasma emitting on-axis 77 ns before the main x-ray burst.

  11. Reliability of frames of reference used for tibial component rotation in total knee arthroplasty.

    PubMed

    Page, Stephen R; Deakin, Angela H; Payne, Anthony P; Picard, Frederic

    2011-01-01

    This study evaluated seven different frames of reference used for tibial component rotation in total knee arthroplasty (TKA) to determine which ones showed good reliability between bone specimens. An optoelectronic system based around a computer-assisted surgical navigation system was used to measure and locate 34 individual anatomical landmarks on 40 tibias. Each particular frame of reference was reconstructed from a group of data points taken from the surface of each bone. The transverse axis was used as the baseline to which the other axes were compared, and the differences in angular rotation between the other six reference frames and the transverse axis were calculated. There was high variability in the tibial rotational alignment associated with all frames of reference. Of the references widely used in current TKA procedures, the tibial tuberosity axis and the anterior condylar axis had lower standard deviations (6.1° and 7.3°, respectively) than the transmalleolar axis and the posterior condylar axis (9.3° for both). In conclusion, we found high variability in the frames of reference used for tibial rotation alignment. However, the anterior condylar axis and transverse axis may warrant further tests with the use of navigation. Combining different frames of reference such as the tibial tuberosity axis, anterior condylar axis and transverse axis may reduce the range of errors found in all of these measurements.

  12. Marine products with anti-protozoal activity: a review.

    PubMed

    García, Marley; Monzote, Lianet

    2014-01-01

    The marine organisms are a rich source of varied natural products with unique functionality. A variety of natural products of new molecular structures with diverse biological activities have been reported from marine flora and fauna for treatment and/or prevention of human diseases. The present review briefly illustrates current status of marine products as antiprotozoal agents. The in vitro and in vivo studies of marine algae, invertebrates and micro-organism against different protozoa parasites are included. The marine products studied, according to international criterions for selection of more promisory products in the different models reported, demonstrated their potentialities as antiprozoal agents. Herein, the interest of scientific community to search new alternatives from marine environment has been demonstrated.

  13. Superconducting magnetic coil

    DOEpatents

    Aized, D.; Schwall, R.E.

    1999-06-22

    A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil. 15 figs.

  14. 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.

  15. Suicide Attempts and Suicide among Marines: A Decade of Follow-Up

    ERIC Educational Resources Information Center

    Gradus, Jaimie L.; Shipherd, Jillian C.; Suvak, Michael K.; Giasson, Hannah L.; Miller, Matthew

    2013-01-01

    Suicidal behavior among military personnel is of paramount public health importance because of the increased risk of death from suicide in this population. Pre- and post-Marine recruit training risk factors for suicide attempts among current and former Marines were examined in 10 years following recruit training. The characteristics of the…

  16. Complete braided adsorbent for marine testing to demonstrate 3g-U/kg-adsorbent

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

    Janke, Chris; Yatsandra, Oyola; Mayes, Richard

    ORNL has manufactured four braided adsorbents that successfully demonstrated uranium adsorption capacities ranging from 3.0-3.6 g-U/kg-adsorbent in marine testing at PNNL. Four new braided and leno woven fabric adsorbents have also been prepared by ORNL and are currently undergoing marine testing at PNNL.

  17. Impacts of changing ocean circulation on the distribution of marine microplastic litter.

    PubMed

    Welden, Natalie Ac; Lusher, Amy L

    2017-05-01

    Marine plastic pollution is currently a major scientific focus, with attention paid to its distribution and impacts within ecosystems. With recent estimates indicating that the mass of plastic released to the marine environment may reach 250 million metric tons by 2025, the effects of plastic on our oceans are set to increase. Distribution of microplastics, those plastics measuring less than 5 mm, are of increasing concern because they represent an increasing proportion of marine litter and are known to interact with species in a range of marine habitats. The local abundance of microplastic is dependent on a complex interaction between the scale of local plastic sources and prevailing environmental conditions; as a result, microplastic distribution is highly heterogeneous. Circulation models have been used to predict plastic distribution; however, current models do not consider future variation in circulation patterns and weather systems caused by a changing climate. In this study, we discuss the potential impacts of global climate change on the abundance and distribution of marine plastic pollution. Integr Environ Assess Manag 2017;13:483-487. © 2017 SETAC. © 2017 SETAC.

  18. Biosensors for marine applications. We all need the sea, but does the sea need biosensors?

    PubMed

    Kröger, Silke; Law, Robin J

    2005-04-15

    The aim of the paper is to explain the rationale behind marine biosensor applications, give an overview of measurement strategies currently employed, summarise some of the relevant available biosensor technology as well as instrumentation requirements for marine sensors and attempt a forward look at what the future might hold in terms of needs and developments. Application areas considered are eutrophication, organism detection, food safety, pollutants, trace metals and ecotoxicology. The drivers for many of these studies are discussed and the policy environment for current and future measurements is outlined.

  19. Cultural Competency Training in the United States Marine Corps: A Prescription for Success in the Long War

    DTIC Science & Technology

    2008-06-13

    CULTURAL COMPETENCY TRAINING IN THE UNITED STATES MARINE CORPS: A PRESCRIPTION FOR SUCCESS IN THE LONG WAR A thesis presented to the...of military units that demonstrated cultural awareness while conducting operations in a foreign land. After presenting a review of the current...Marine Corps Center for Advanced Operational Cultural Learning (CAOCL), advocates teaching Marines enough of a language to do the things they need to

  20. An efficient and economical way to enhance the performance of present HTS Maglev systems by utilizing the anisotropy property of bulk superconductors

    NASA Astrophysics Data System (ADS)

    Deng, Zigang; Wang, Jiasu; Zheng, Jun; Zhang, Ya; Wang, Suyu

    2013-02-01

    We report a simple, efficient and economical way to enhance the levitation or guidance performance of present high-temperature superconducting (HTS) Maglev systems by exploring the anisotropic properties of the critical current density in the a-b plane and along the c-axis of bulk superconductors. In the method, the bulk laying mode with different c-axis directions is designed to match with the magnetic field configuration of the applied permanent magnet guideway (PMG). Experimental results indicate that more than a factor of two improvement in the levitation force or guidance force is achieved when changing the laying mode of bulk superconductors from the traditional fashion of keeping the c-axis vertical to the PMG surface to the studied one of keeping the c-axis parallel to the PMG surface, at the maximum horizontal and vertical magnetic field positions of the PMG, respectively. These phenomena resulted from the physical nature of the generated levitation force and guidance force (electromagnetic forces) and the fact that there are different critical current densities in the a-b plane and along the c axis. Based on the experimental results, new HTS Maglev systems can be designed to meet the requirements of practical heavy-load or curved-route applications.

  1. Prospects for Off-axis Current Drive via High Field Side Lower Hybrid Current Drive in DIII-D

    NASA Astrophysics Data System (ADS)

    Wukitch, S. J.; Shiraiwa, S.; Wallace, G. M.; Bonoli, P. T.; Holcomb, C.; Park, J. M.; Pinsker, R. I.

    2017-10-01

    An outstanding challenge for an economical, steady state tokamak is efficient off-axis current drive scalable to reactors. Previous studies have focused on high field side (HFS) launch of lower hybrid waves for current drive (LHCD) in double null configurations in reactor grade plasmas. The goal of this work is to find a HFS LHCD scenario for DIII-D that balances coupling, power penetration and damping. The higher magnetic field on the HFS improves wave accessibility, which allows for lower n||waves to be launched. These waves penetrate farther into the plasma core before damping at higher Te yielding a higher current drive efficiency. Utilizing advanced ray tracing and Fokker Planck simulation tools (GENRAY+CQL3D), wave penetration, absorption and drive current profiles in high performance DIII-D H-Mode plasmas were investigated. We found LH scenarios with single pass absorption, excellent wave penetration to r/a 0.6-0.8, FWHM r/a=0.2 and driven current up to 0.37 MA/MW coupled. These simulations indicate that HFS LHCD has potential to achieve efficient off-axis current drive in DIII-D and the latest results will be presented. Work supported by U.S. Dept. of Energy, Office of Science, Office of Fusion Energy Sciences, using User Facility DIII-D, under Award No. DE-FC02-04ER54698 and Contract No. DE-FC02-01ER54648 under Scientific Discovery through Advanced Computing Initiative.

  2. Influence of turbulence on the wake of a marine current turbine simulator.

    PubMed

    Blackmore, T; Batten, W M J; Bahaj, A S

    2014-10-08

    Marine current turbine commercial prototypes have now been deployed and arrays of multiple turbines under design. The tidal flows in which they operate are highly turbulent, but the characteristics of the inflow turbulence have not being considered in present design methods. This work considers the effects of inflow turbulence on the wake behind an actuator disc representation of a marine current turbine. Different turbulence intensities and integral length scales were generated in a large eddy simulation using a gridInlet, which produces turbulence from a grid pattern on the inlet boundary. The results highlight the significance of turbulence on the wake profile, with a different flow regime occurring for the zero turbulence case. Increasing the turbulence intensity reduced the velocity deficit and shifted the maximum deficit closer to the turbine. Increasing the integral length scale increased the velocity deficit close to the turbine due to an increased production of turbulent energy. However, the wake recovery was increased due to the higher rate of turbulent mixing causing the wake to expand. The implication of this work is that marine current turbine arrays could be further optimized, increasing the energy yield of the array when the site-specific turbulence characteristics are considered.

  3. Influence of turbulence on the wake of a marine current turbine simulator

    PubMed Central

    Blackmore, T.; Batten, W. M. J.; Bahaj, A. S.

    2014-01-01

    Marine current turbine commercial prototypes have now been deployed and arrays of multiple turbines under design. The tidal flows in which they operate are highly turbulent, but the characteristics of the inflow turbulence have not being considered in present design methods. This work considers the effects of inflow turbulence on the wake behind an actuator disc representation of a marine current turbine. Different turbulence intensities and integral length scales were generated in a large eddy simulation using a gridInlet, which produces turbulence from a grid pattern on the inlet boundary. The results highlight the significance of turbulence on the wake profile, with a different flow regime occurring for the zero turbulence case. Increasing the turbulence intensity reduced the velocity deficit and shifted the maximum deficit closer to the turbine. Increasing the integral length scale increased the velocity deficit close to the turbine due to an increased production of turbulent energy. However, the wake recovery was increased due to the higher rate of turbulent mixing causing the wake to expand. The implication of this work is that marine current turbine arrays could be further optimized, increasing the energy yield of the array when the site-specific turbulence characteristics are considered. PMID:25294966

  4. Mechanical Extraction of Power From Ocean Currents and Tides

    NASA Technical Reports Server (NTRS)

    Jones, Jack; Chao, Yi

    2010-01-01

    A proposed scheme for generating electric power from rivers and from ocean currents, tides, and waves is intended to offer economic and environmental advantages over prior such schemes, some of which are at various stages of implementation, others of which have not yet advanced beyond the concept stage. This scheme would be less environmentally objectionable than are prior schemes that involve the use of dams to block rivers and tidal flows. This scheme would also not entail the high maintenance costs of other proposed schemes that call for submerged electric generators and cables, which would be subject to degradation by marine growth and corrosion. A basic power-generation system according to the scheme now proposed would not include any submerged electrical equipment. The submerged portion of the system would include an all-mechanical turbine/pump unit that would superficially resemble a large land-based wind turbine (see figure). The turbine axis would turn slowly as it captured energy from the local river flow, ocean current, tidal flow, or flow from an ocean-wave device. The turbine axis would drive a pump through a gearbox to generate an enclosed flow of water, hydraulic fluid, or other suitable fluid at a relatively high pressure [typically approx.500 psi (approx.3.4 MPa)]. The pressurized fluid could be piped to an onshore or offshore facility, above the ocean surface, where it would be used to drive a turbine that, in turn, would drive an electric generator. The fluid could be recirculated between the submerged unit and the power-generation facility in a closed flow system; alternatively, if the fluid were seawater, it could be taken in from the ocean at the submerged turbine/pump unit and discharged back into the ocean from the power-generation facility. Another alternative would be to use the pressurized flow to charge an elevated reservoir or other pumped-storage facility, from whence fluid could later be released to drive a turbine/generator unit at a time of high power demand. Multiple submerged turbine/pump units could be positioned across a channel to extract more power than could be extracted by a single unit. In that case, the pressurized flows in their output pipes would be combined, via check valves, into a wider pipe that would deliver the combined flow to a power-generating or pumped-storage facility.

  5. Methods of fabricating a conductor assembly having a curvilinear arcuate shape

    DOEpatents

    Meinke, Rainer [Melbourne, FL

    2011-08-23

    A method for manufacture of a conductor assembly along a curvilinear axis. The assembly may be of the type which, when conducting current, generates a magnetic field or in which, in the presence of a changing magnetic field, a voltage is induced. In one example, the assembly includes a structure having a curved shape extending along the axis. A surface of the structure is positioned for formation of a channel along the curved shape. The structure is rotated about a second axis. While rotating the structure, a channel is formed in the surface that results in a helical shape in the structure. The channel extends both around and along the first axis.

  6. The Relationship Between Stressful Life Events and Axis I Diagnoses Among Adolescent Offspring of Probands With Bipolar and Non-Bipolar Psychiatric Disorders and Healthy Controls: The Pittsburgh Bipolar Offspring Study (BIOS).

    PubMed

    Pan, Lisa A; Goldstein, Tina R; Rooks, Brian T; Hickey, Mary; Fan, Jie Yu; Merranko, John; Monk, Kelly; Diler, Rasim S; Sakolsky, Dara J; Hafeman, Danella; Iyengar, Satish; Goldstein, Benjamin; Kupfer, David J; Axelson, David A; Brent, David A; Birmaher, Boris

    2017-03-01

    Previous studies have explored the role of stressful life events in the development of mood disorders. We examined the frequency and nature of stressful life events as measured by the Stressful Life Events Schedule (SLES) among 3 groups of adolescent offspring of probands with bipolar (BD), with non-BD psychiatric disorders, and healthy controls. Furthermore, we examined the relationship between stressful life events and the presence of DSM-IV Axis I disorders in these offspring. Stressful life events were characterized as dependent, independent, or uncertain (neither dependent nor independent) and positive, negative, or neutral (neither positive nor negative). Offspring of probands with BD aged 13-18 years (n = 269), demographically matched offspring of probands with non-BD Axis I disorders (n = 88), and offspring of healthy controls (n = 81) from the Pittsburgh Bipolar Offspring Study were assessed from 2002 to 2007 with standardized instruments at intake. Probands completed the SLES for their offspring for life events within the prior year. Life events were evaluated with regard to current Axis I diagnoses in offspring after adjusting for confounds. After adjusting for demographic and clinical between-group differences (in probands and offspring), offspring of probands with BD had greater independent (χ² = 11.96, P < .04) and neutral (χ² = 17.99, P < .003) life events compared with offspring of healthy controls and greater number of more severe stressful life events than offspring of healthy controls, but not offspring of probands with non-BD. Offspring of BD probands with comorbid substance use disorder reported more independent stressful life events compared to those without comorbid substance use disorder (P = .024). Greater frequency and severity of stressful life events were associated with current Axis I disorder in offspring of both probands with BD and probands with other Axis I disorders regardless of dependency or valence. Greater frequency and severity of stressful life events were associated with greater current Axis I disorder in all offspring. Offspring of probands with BD have greater exposure to independent and neutral life events than offspring of healthy controls. Greater frequency and severity of stressful life events were associated with Axis I disorder in offspring of both BD and non-BD affected probands. © Copyright 2017 Physicians Postgraduate Press, Inc.

  7. Study of morphological variation of northern Neotropical Ariidae reveals conservatism despite macrohabitat transitions.

    PubMed

    Stange, Madlen; Aguirre-Fernández, Gabriel; Salzburger, Walter; Sánchez-Villagra, Marcelo R

    2018-03-27

    Morphological convergence triggered by trophic adaptations is a common pattern in adaptive radiations. The study of shape variation in an evolutionary context is usually restricted to well-studied fish models. We take advantage of the recently revised systematics of New World Ariidae and investigate skull shape evolution in six genera of northern Neotropical Ariidae. They constitute a lineage that diversified in the marine habitat but repeatedly adapted to freshwater habitats. 3D geometric morphometrics was applied for the first time in catfish skulls and phylogenetically informed statistical analyses were performed to test for the impact of habitat on skull diversification after habitat transition in this lineage. We found that skull shape is conserved throughout phylogeny. A morphospace analysis revealed that freshwater and marine species occupy extreme ends of the first principal component axis and that they exhibit similar Procrustes variances. Yet freshwater species occupy the smallest shape space compared to marine and brackish species (based on partial disparity), and marine and freshwater species have the largest Procrustes distance to each other. We observed a single case of shape convergence as derived from 'C-metrics', which cannot be explained by the occupation of the same habitat. Although Ariidae occupy such a broad spectrum of different habitats from sea to freshwater, the morphospace analysis and analyses of shape and co-variation with habitat in a phylogenetic context shows that conservatism dominates skull shape evolution among ariid genera.

  8. The HGF/c-MET Axis as a Critical Driver of Resistance to Androgen Suppression in Metastatic Castrate-Resistant Prostate Cancer

    DTIC Science & Technology

    2016-10-01

    c-MET axis in metastatic castration-resistant prostate cancer. During the current funding period, we have confirmed an inverse relationship between...resistant prostate cancer. Neoplasia 18:1-9, 2016. PMCID: 26806347. In this manuscript, we provided mechanistic evidence establishing the inverse

  9. Terahertz electron cyclotron maser interactions with an axis-encircling electron beam

    NASA Astrophysics Data System (ADS)

    Li, G. D.; Kao, S. H.; Chang, P. C.; Chu, K. R.

    2015-04-01

    To generate terahertz radiation via the electron cyclotron maser instability, harmonic interactions are essential in order to reduce the required magnetic field to a practical value. Also, high-order mode operation is required to avoid excessive Ohmic losses. The weaker harmonic interaction and mode competition associated with an over-moded structure present challenging problems to overcome. The axis-encircling electron beam is a well-known recipe for both problems. It strengthens the harmonic interaction, as well as minimizing the competing modes. Here, we examine these advantages through a broad data base obtained for a low-power, step-tunable, gyrotron oscillator. Linear results indicate far more higher-harmonic modes can be excited with an axis-encircling electron beam than with an off-axis electron beam. However, multi-mode, time-dependent simulations reveal an intrinsic tendency for a higher-harmonic mode to switch over to a lower-harmonic mode at a high beam current or upon a rapid current rise. Methods are presented to identify the narrow windows in the parameter space for stable harmonic interactions.

  10. The relationship between stressful life events and Axis I diagnoses among adolescent offspring of probands with bipolar and non-bipolar psychiatric disorders and healthy controls

    PubMed Central

    Pan, Lisa A.; Goldstein, Tina R.; Rooks, Brian T.; Hickey, Mary; Fan, Jie Yu; Merranko, John; Monk, Kelly; Diler, Rasim S.; Sakolsky, Dara J.; Hafeman, Daniella; Iyengar, Satish; Goldstein, Benjamin; Kupfer, David J.; Axelson, David; Brent, David A.; Birmaher, Boris

    2018-01-01

    Background Previous studies have explored the role of stressful life events in the development of mood disorders. We examined the frequency and nature of stressful life events as measured by the Stressful Life Events Scale(SLES) among three groups of adolescent offspring of probands: with bipolar(BD), with non-BD psychiatric disorders, and healthy control(HC). Furthermore, we examined the relationship between stressful life events and presence of DSM-IV Axis I disorders in these offspring. Stressful life events were characterized as dependent, independent, or uncertain (neither dependent or independent), and positive, negative, and neutral (neither positive or negative). Method Offspring of probands with BD aged 13–18 years(N=269), demographically-matched offspring of probands with non-BD Axis I disorders(N=88), and HC probands(N=81) from the Pittsburgh Bipolar Offspring Study were assessed from 2002–2007 with standardized instruments at intake. Probands completed the SLES for their offspring for life events within the prior year. Life events were evaluated with regard to current offspring Axis I diagnoses after adjusting for confounds. Results After adjusting for demographic and clinical between-group differences(in probands and offspring), offspring of BD probands had greater independent and neutral life events compared with HC offspring and greater number of more severe stressful life events than HC offspring, but not non-BD offspring. Offspring of BD probands with comorbid substance use disorder reported more independent stressful life events. Greater frequency and severity of stressful life events were associated with current Axis I disorder in offspring of both BD and non-BD affected probands regardless of dependency or valence. Greater frequency and severity of stressful life events were associated with greater current Axis I disorder in all offspring. Conclusions Offspring of BD probands have greater exposure to independent and neutral life events than HC offspring. Greater frequency and severity of stressful life events was associated with Axis I disorder in offspring of both BD and non-BD affected probands. PMID:28199068

  11. Evaluation, development, and characterization of superconducting materials for space applications

    NASA Technical Reports Server (NTRS)

    Thorpe, Arthur N.

    1990-01-01

    The anisotropic electromagnetic features of a grain-aligned YBa2Cu3O(x) bulk sample derived from a process of long-time partial melt growth were investigated by the measurements of direct current magnetization (at 77 K) and alternating current susceptibility as a function of temperature, with the fields applied parallel and perpendicular to the c axis, respectively. The extended Bean model was further studied and applied to explain the experimental results. Upon comparison of the grain-aligned sample with pure single crystal materials, it is concluded that because of the existence of more effective pinning sites in the grain-aligned sample, not only its critical current density perpendicular to the c axis is improved, but the one parallel to the c axis is improved even more significantly. The anisotropy in the critical current densities in the grain-aligned sample at 77 K is at least one to two orders of magnitude smaller than in the pure single crystal. The measurement of anisotropy of alternating current susceptibility as a function of temperature, especially its imaginary part, shows that there are still some residues of interlayer weak links in the grain-aligned samples, but they are quite different from and far less serious than the weak links in the sintered sample.

  12. Application of External Axis in Robot-Assisted Thermal Spraying

    NASA Astrophysics Data System (ADS)

    Deng, Sihao; Fang, Dandan; Cai, Zhenhua; Liao, Hanlin; Montavon, Ghislain

    2012-12-01

    Currently, industrial robots are widely used in the process of thermal spraying because of their high efficiency, security, and repeatability. Although robots are found suitable for use in industrial productions, they have some natural disadvantages because of their six-axis mechanical linkages. When a robot performs a series of stages of production, it could be hard to move from one to another because a few axes reach their limit value. For this reason, an external axis should be added to the robot system to extend the reachable space of the robots. This article concerns the application of external axis on ABB robots in thermal spraying and the different methods of off-line programming with external axis in the virtual environment. The developed software toolkit was applied to coat real workpiece with a complex geometry in atmospheric plasma spraying).

  13. Psychiatric comorbidity may not predict suicide during and after hospitalization. A nested case-control study with blinded raters.

    PubMed

    Walby, Fredrik A; Odegaard, Erik; Mehlum, Lars

    2006-06-01

    To investigate the differential impact of DSM-IV axis-I and axis-II disorders on completed suicide and to study if psychiatric comorbidity increases the risk of suicide in currently and previously hospitalized psychiatric patients. A nested case-control design based on case notes from 136 suicides and 166 matched controls. All cases and controls were rediagnosed using the SCID-CV for axis-I and the DSM-IV criteria for axis-II disorders and the inter-rater reliability was satisfactory. Raters were blind to the case and control status and the original hospital diagnoses. Depressive disorders and bipolar disorders were associated with an increased risk of suicide. No such effect was found for comorbidity between axis-I disorders and for comorbidity between axis-I and axis-II disorders. Psychiatric diagnoses, although made using a structured and criteria-based approach, was based on information recorded in case notes. Axis-II comorbidity could only be investigated at an aggregated level. Psychiatric comorbidity did not predict suicide in this sample. Mood disorders did, however, increase the risk significantly independent of history of previous suicide attempts. Both findings can inform identification and treatment of patients at high risk for completed suicide.

  14. Electric field induced spin-polarized current

    DOEpatents

    Murakami, Shuichi; Nagaosa, Naoto; Zhang, Shoucheng

    2006-05-02

    A device and a method for generating an electric-field-induced spin current are disclosed. A highly spin-polarized electric current is generated using a semiconductor structure and an applied electric field across the semiconductor structure. The semiconductor structure can be a hole-doped semiconductor having finite or zero bandgap or an undoped semiconductor of zero bandgap. In one embodiment, a device for injecting spin-polarized current into a current output terminal includes a semiconductor structure including first and second electrodes, along a first axis, receiving an applied electric field and a third electrode, along a direction perpendicular to the first axis, providing the spin-polarized current. The semiconductor structure includes a semiconductor material whose spin orbit coupling energy is greater than room temperature (300 Kelvin) times the Boltzmann constant. In one embodiment, the semiconductor structure is a hole-doped semiconductor structure, such as a p-type GaAs semiconductor layer.

  15. Passive magnetic bearing for a motor-generator

    DOEpatents

    Post, Richard F [Walnut Creek, CA

    2006-07-18

    Conductive lap windings are interleaved with conventional loops in the stator of a motor-generator. The rotor provides magnetic induction lines that, when rotated, cut across the lap windings and the loops. When the rotor is laterally displaced from its equilibrium axis of rotation, its magnetic lines of induction induce a current in the interleaved lap windings. The induced current interacts with the magnetic lines of induction of the rotor in accordance with Lenz's law to generate a radial force that returns the rotor to its equilibrium axis of rotation.

  16. Single-mode VCSEL operation via photocurrent feedback

    NASA Astrophysics Data System (ADS)

    Riyopoulos, Spilios

    1999-04-01

    On-axis channeling through the use of photoactive layers in VCSEL cavities is proposed to counteract hole burning and mode switching. The photoactive layers act as variable resistivity screens whose radial `aperture' is controlled by the light itself. It is numerically demonstrated that absorption of a small fraction of the light intensity suffices for significant on axis current peaking and single mode operation at currents many times threshold, with minimum efficiency loss and optical mode distortion. Fabrication is implemented during the molecular beam epitaxy phase without wafer post processing, as for oxide apertures.

  17. Strong Orientation-Dependent Spin-Orbit Torque in Thin Films of the Antiferromagnet Mn2Au

    NASA Astrophysics Data System (ADS)

    Zhou, X. F.; Zhang, J.; Li, F.; Chen, X. Z.; Shi, G. Y.; Tan, Y. Z.; Gu, Y. D.; Saleem, M. S.; Wu, H. Q.; Pan, F.; Song, C.

    2018-05-01

    Antiferromagnets with zero net magnetic moment, strong anti-interference, and ultrafast switching speed are potentially competitive in high-density information storage. The body-centered tetragonal antiferromagnet Mn2Au with opposite-spin sublattices is a unique metallic material for Néel-order spin-orbit-torque (SOT) switching. We investigate the SOT switching in quasiepitaxial (103), (101) and (204) Mn2Au films prepared by a simple magnetron sputtering method. We demonstrate current-induced antiferromagnetic moment switching in all of the prepared Mn2Au films by using a short current pulse at room temperature, whereas differently oriented films exhibit distinguished switching characters. A direction-independent reversible switching is attained in Mn2Au (103) films due to negligible magnetocrystalline anisotropy energy, while for Mn2Au (101) and (204) films, the switching is invertible with the current applied along the in-plane easy axis and its vertical axis, but it becomes attenuated seriously during initial switching circles when the current is applied along the hard axis because of the existence of magnetocrystalline anisotropy energy. Besides the fundamental significance, the strong orientation-dependent SOT switching, which is not realized, irrespective of ferromagnet and antiferromagnet, provides versatility for spintronics.

  18. Shipping, Ships and Waterways: A Marine Education Infusion Unit. Northern New England Marine Education Project.

    ERIC Educational Resources Information Center

    Maine Univ., Orono. Coll. of Education.

    This multidisciplinary unit is designed to increase familiarity with various types of ships and purposes for different varieties of marine vessels. It seeks to increase familiarity with routes of ocean shipping and the effect of ocean conditions such as currents upon shipping route patterns. A discussion treats the uses of various navigation…

  19. Chapter 21: Oceanographic Processes and Marine Productivity in Waters Offshore of Marbled Murrelet Breeding Habitat

    Treesearch

    Jr. Hunt

    1995-01-01

    Marbled Murrelets (Brachyramphus marmoratus) occupy nearshore waters in the eastern North Pacific Ocean from central California to the Aleutian Islands. The offshore marine ecology of these waters is dominated by a series of currents roughly parallel to the coast that determine marine productivity of shelf waters by influencing the rate of nutrient...

  20. Population genetic signatures of a climate change driven marine range extension.

    PubMed

    Ramos, Jorge E; Pecl, Gretta T; Moltschaniwskyj, Natalie A; Semmens, Jayson M; Souza, Carla A; Strugnell, Jan M

    2018-06-22

    Shifts in species distribution, or 'range shifts', are one of the most commonly documented responses to ocean warming, with important consequences for the function and structure of ecosystems, and for socio-economic activities. Understanding the genetic signatures of range shifts can help build our knowledge of the capacity of species to establish and persist in colonised areas. Here, seven microsatellite loci were used to examine the population connectivity, genetic structure and diversity of Octopus tetricus, which has extended its distribution several hundred kilometres polewards associated with the southwards extension of the warm East Australian Current along south-eastern Australia. The historical distribution and the range extension zones had significant genetic differences but levels of genetic diversity were comparable. The population in the range extension zone was sub-structured, contained relatively high levels of self-recruitment and was sourced by migrants from along the entire geographic distribution. Genetic bottlenecks and changes in population size were detected throughout the range extension axis. Persistent gene flow from throughout the historical zone and moderate genetic diversity may buffer the genetic bottlenecks and favour the range extension of O. tetricus. These characteristics may aid adaptation, establishment, and long-term persistence of the population in the range extension zone.

  1. Design of multi-mission chemical propulsion modules for planetary orbiters. Volume 1: Summary report

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Results are presented of a conceptual design and feasibility study of chemical propulsion stages that can serve as modular propulsion units, with little or no modification, on a variety of planetary orbit missions, including orbiters of Mercury, Saturn, and Uranus. Planetary spacecraft of existing design or currently under development, viz., spacecraft of the Pioneer and Mariner families, are assumed as payload vehicles. Thus, operating requirements of spin-stabilized and 3-axis stabilized spacecraft have to be met by the respective propulsion module designs. As launch vehicle for these missions the Shuttle orbiter and interplanetary injection stage, or Tug, plus solid-propellant kick motor was assumed. Accommodation constraints and interfaces involving the payloads and the launch vehicle are considered in the propulsion module design. The applicability and performance advantages were evaluated of the space-storable high-energy bipropellants. The incentive for using this advanced propulsion technology on planetary missions is the much greater performance potential when orbit insertion velocities in excess of 4 km/sec are required, as in the Mercury orbiter. Design analyses and performance tradeoffs regarding earth-storable versus space-storable propulsion systems are included. Cost and development schedules of multi-mission versus custom-designed propulsion modules are examined.

  2. On LAM's and SAM's for Halley's rotation

    NASA Technical Reports Server (NTRS)

    Peale, Stanton J.

    1992-01-01

    Non principal axis rotation for comet Halley is inferred from dual periodicities evident in the observations. The modes where the spin axis precesses around the axis of minimum moment of inertia (long axis mode or LAM) and where it precesses around the axis of maximum moment of inertia (short axis mode or SAM) are described from an inertial point of view. The currently favored LAM model for Halley's rotation state satisfies observational and dynamical constraints that apparently no SAM can satisfy. But it cannot reproduce the observed post perihelion brightening through seasonal illumination of localized sources on the nucleus, whereas a SAM can easily produce post or pre perihelion brightening by this mechanism. However, the likelihood of a LAM rotation for elongated nuclei of periodic comets such as Halley together with Halley's extreme post perihelion behavior far from the Sun suggest that Halley's post perihelion brightening may be due to effects other than seasonal illumination of localized sources, and therefore such brightening may not constrain its rotation state.

  3. Physical and Numerical Model Studies of Cross-flow Turbines Towards Accurate Parameterization in Array Simulations

    NASA Astrophysics Data System (ADS)

    Wosnik, M.; Bachant, P.

    2014-12-01

    Cross-flow turbines, often referred to as vertical-axis turbines, show potential for success in marine hydrokinetic (MHK) and wind energy applications, ranging from small- to utility-scale installations in tidal/ocean currents and offshore wind. As turbine designs mature, the research focus is shifting from individual devices to the optimization of turbine arrays. It would be expensive and time-consuming to conduct physical model studies of large arrays at large model scales (to achieve sufficiently high Reynolds numbers), and hence numerical techniques are generally better suited to explore the array design parameter space. However, since the computing power available today is not sufficient to conduct simulations of the flow in and around large arrays of turbines with fully resolved turbine geometries (e.g., grid resolution into the viscous sublayer on turbine blades), the turbines' interaction with the energy resource (water current or wind) needs to be parameterized, or modeled. Models used today--a common model is the actuator disk concept--are not able to predict the unique wake structure generated by cross-flow turbines. This wake structure has been shown to create "constructive" interference in some cases, improving turbine performance in array configurations, in contrast with axial-flow, or horizontal axis devices. Towards a more accurate parameterization of cross-flow turbines, an extensive experimental study was carried out using a high-resolution turbine test bed with wake measurement capability in a large cross-section tow tank. The experimental results were then "interpolated" using high-fidelity Navier--Stokes simulations, to gain insight into the turbine's near-wake. The study was designed to achieve sufficiently high Reynolds numbers for the results to be Reynolds number independent with respect to turbine performance and wake statistics, such that they can be reliably extrapolated to full scale and used for model validation. The end product of this work will be a cross-flow turbine actuator line model to be used as an extension to the OpenFOAM computational fluid dynamics (CFD) software framework, which will likely require modifications to commonly-used dynamic stall models, in consideration of the turbines' high angle of attack excursions during normal operation.

  4. Blade design and performance analysis on the horizontal axis tidal current turbine for low water level channel

    NASA Astrophysics Data System (ADS)

    Chen, C. C.; Choi, Y. D.; Y Yoon, H.

    2013-12-01

    Most tidal current turbine design are focused on middle and large scale for deep sea, less attention was paid in low water level channel, such as the region around the islands, coastal seas and rivers. This study aims to develop a horizontal axis tidal current turbine rotor blade which is applicable to low water level island region in southwest of Korea. The blade design is made by using BEMT(blade element momentum theory). The section airfoil profile of NACA63-415 is used, which shows good performance of lift coefficient and drag coefficient. Power coefficient, pressure and velocity distributions are investigated according to TSR by CFD analysis.

  5. Evolved to fail: Bacteria induce flagellar buckling to reorient

    NASA Astrophysics Data System (ADS)

    Son, Kwangmin; Guasto, Jeffrey S.; Stocker, Roman

    2012-11-01

    Many marine bacteria swim with a single helical flagellum connected to a rotary motor via a 100 nm long universal joint called the ``hook.'' While these bacteria have seemingly just one degree of freedom, allowing them to swim only back and forth, they in fact exhibit large angular reorientations mediated by off-axis ``flicks'' of their flagellum. High-speed video microscopy revealed the mechanism underpinning this turning behavior: the buckling of the hook during the exceedingly brief (10 ms) forward run that follows a reversal. Direct measurements of the hook's mechanical properties corroborated this result, as the hook's structural stability is governed by the Sperm number, which compares the compressive load from propulsion to the elastic restoring force of the hook. Upon decreasing the Sperm number below a critical value by reducing the swimming speed, the frequency of flicks diminishes sharply, consistent with the criticality of buckling. This elegant, under-actuated turning mechanism appears widespread among marine bacteria and may provide a novel design concept in micro-robotics.

  6. Defense.gov Special Report: California Wildfires

    Science.gov Websites

    Fight California Wildfires U.S. Marines and aircraft with 3rd Marine Aircraft Wing and fire crews on Wildfires CDC Emergency Preparedness - Wildfires Current California Fire Information (CA.gov) Official Camp

  7. NOAA MF/HF VOICE - 4125 kHz

    Science.gov Websites

    current weather conditions in their operating area. All NWS marine forecasts rely heavily on the Voluntary weather conditions in their operating area. Home, Parent Office, Marine, Tropical, and Tsunami Services

  8. Strain partitioning in southeastern Alaska: Is the Chatham Strait Fault active?

    USGS Publications Warehouse

    Brothers, Daniel; Elliott, Julie L.; Conrad, James E.; Haeussler, Peter J.; Kluesner, Jared

    2018-01-01

    A 1200 km-long transform plate boundary passes through southeastern Alaska and northwestern British Columbia and represents one of the most seismically active, but poorly understood continental margins of North America. Although most of the plate motion is accommodated by the right-lateral Queen Charlotte–Fairweather Fault (QCFF) System, which has produced at least six M > 7 earthquakes since 1920, seismic hazard assessments also include the Chatham Strait Fault (CSF) as a potentially active, 400 km-long strike slip fault that cuts northward through southeastern Alaska, connecting with the Eastern Denali Fault. Nearly the entire length of the CSF is submerged beneath Chatham Strait and Lynn Canal and has never been systematically imaged using high-resolution marine geophysical approaches. In this study we present an integrated analysis of new marine seismic reflectiondata acquired across Lynn Canal and tectonic block modeling constrained by data from continuous and campaign GPS sites. Seismic profiles cross the CSF at twelve locations spanning ∼50 km of fault length; they reveal thick (up to 300 m) packages of glaciomarine sedimentary facies emplaced on an unconformity surface that formed during the Last Glacial Maximum (LGM). Localized warping of post-LGM stratigraphy (∼13.9 kyr B.P. to present) appears to correlate with sediment drape on basement topography and current-controlled deposition. There is no evidence for an active fault along the axis of Lynn Canal in the seismic reflection data. Crustal block models constrained by GPS data allow, but do not require, a maximum slip rate of 2–3 mm/yr along the CSF; higher slip rates on the CSF result in significant misfit to GPS data in the surrounding region. Based on the combined marine geophysical and GPS observations, it is plausible that the CSF has not generated resolvable coseismic deformation in the last ∼13 ka and that the modern slip-rate is <1 mm/yr. We propose that models for strain transfer between the QCFF and the Denali Fault, and seismic hazard maps in general, may need to be reevaluated.

  9. Strain partitioning in Southeastern Alaska: Is the Chatham Strait Fault active?

    NASA Astrophysics Data System (ADS)

    Brothers, Daniel S.; Elliott, Julie L.; Conrad, James E.; Haeussler, Peter J.; Kluesner, Jared W.

    2018-01-01

    A 1200 km-long transform plate boundary passes through southeastern Alaska and northwestern British Columbia and represents one of the most seismically active, but poorly understood continental margins of North America. Although most of the plate motion is accommodated by the right-lateral Queen Charlotte-Fairweather Fault (QCFF) System, which has produced at least six M > 7 earthquakes since 1920, seismic hazard assessments also include the Chatham Strait Fault (CSF) as a potentially active, 400 km-long strike slip fault that cuts northward through southeastern Alaska, connecting with the Eastern Denali Fault. Nearly the entire length of the CSF is submerged beneath Chatham Strait and Lynn Canal and has never been systematically imaged using high-resolution marine geophysical approaches. In this study we present an integrated analysis of new marine seismic reflection data acquired across Lynn Canal and tectonic block modeling constrained by data from continuous and campaign GPS sites. Seismic profiles cross the CSF at twelve locations spanning ∼50 km of fault length; they reveal thick (up to 300 m) packages of glaciomarine sedimentary facies emplaced on an unconformity surface that formed during the Last Glacial Maximum (LGM). Localized warping of post-LGM stratigraphy (∼13.9 kyr B.P. to present) appears to correlate with sediment drape on basement topography and current-controlled deposition. There is no evidence for an active fault along the axis of Lynn Canal in the seismic reflection data. Crustal block models constrained by GPS data allow, but do not require, a maximum slip rate of 2-3 mm/yr along the CSF; higher slip rates on the CSF result in significant misfit to GPS data in the surrounding region. Based on the combined marine geophysical and GPS observations, it is plausible that the CSF has not generated resolvable coseismic deformation in the last ∼13 ka and that the modern slip-rate is <1 mm/yr. We propose that models for strain transfer between the QCFF and the Denali Fault, and seismic hazard maps in general, may need to be reevaluated.

  10. The European Marine Strategy: Noise Monitoring in European Marine Waters from 2014.

    PubMed

    Dekeling, René; Tasker, Mark; Ainslie, Michael; Andersson, Mathias; André, Michel; Borsani, Fabrizio; Brensing, Karsten; Castellote, Manuel; Dalen, John; Folegot, Thomas; van der Graaf, Sandra; Leaper, Russell; Liebschner, Alexander; Pajala, Jukka; Robinson, Stephen; Sigray, Peter; Sutton, Gerry; Thomsen, Frank; Werner, Stefanie; Wittekind, Dietrich; Young, John V

    2016-01-01

    The European Marine Strategy Framework Directive requires European member states to develop strategies for their marine waters leading to programs of measures that achieve or maintain good environmental status (GES) in all European seas by 2020. An essential step toward reaching GES is the establishment of monitoring programs, enabling the state of marine waters to be assessed on a regular basis. A register for impulsive noise-generating activities would enable assessment of their cumulative impacts on wide temporal and spatial scales; monitoring of ambient noise would provide essential insight into current levels and any trend in European waters.

  11. Understanding the potential risk to marine mammals from collision with tidal turbines

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

    Copping, Andrea; Grear, Molly; Jepsen, Richard

    The advent of the marine renewable energy industry has raised questions, particularly for tidal turbines, about potential threats to populations of marine mammals. This research examines the sequence of behavioral events that lead up to a potential collision of a marine mammal with a tidal turbine, within the context of the physical environment, the attributes of the tidal device, and the biomechanical properties of a marine mammal that may resist injury from a tidal blade collision. There are currently no data available to determine the risk of collision to a marine mammal, and obtaining those data would be extremely difficult.more » The surrogate data examined in this research (likelihood of a marine mammal being in close proximity to a tidal turbine, biomechanics of marine mammal tissues, and engineering models) provide insight into the interaction.« less

  12. Possible impact of global warming and ocean acidification on underwater sound in northern oceans: another perfect storm

    NASA Astrophysics Data System (ADS)

    Browning, David

    2011-04-01

    The greatest ocean pH change, which will result in lower low frequency sound attenuation, is predicted for higher latitudes. Here shallow sound channel axies exist, allowing the impact on sound to be seen sooner and also more extensively since the principal propagation paths will be near the surface. However, at the same time, higher wind speeds and greater ice breakup,as well as increased ship traffic, could result in higher noise levels. Marine mammals in this environment may have, on one hand, improving communication conditions but also the possibility of increased background noise.

  13. Changing Hydrozoan Bauplans by Silencing Hox-Like Genes

    PubMed Central

    Jakob, Wolfgang; Schierwater, Bernd

    2007-01-01

    Regulatory genes of the Antp class have been a major factor for the invention and radiation of animal bauplans. One of the most diverse animal phyla are the Cnidaria, which are close to the root of metazoan life and which often appear in two distinct generations and a remarkable variety of body forms. Hox-like genes have been known to be involved in axial patterning in the Cnidaria and have been suspected to play roles in the genetic control of many of the observed bauplan changes. Unfortunately RNAi mediated gene silencing studies have not been satisfactory for marine invertebrate organisms thus far. No direct evidence supporting Hox-like gene induced bauplan changes in cnidarians have been documented as of yet. Herein, we report a protocol for RNAi transfection of marine invertebrates and demonstrate that knock downs of Hox-like genes in Cnidaria create substantial bauplan alterations, including the formation of multiple oral poles (“heads”) by Cnox-2 and Cnox-3 inhibition, deformation of the main body axis by Cnox-5 inhibition and duplication of tentacles by Cnox-1 inhibition. All phenotypes observed in the course of the RNAi studies were identical to those obtained by morpholino antisense oligo experiments and are reminiscent of macroevolutionary bauplan changes. The reported protocol will allow routine RNAi studies in marine invertebrates to be established. PMID:17668071

  14. Latest Miocene transtensional rifting of northeast Isla Tiburón, eastern margin of the Gulf of California

    NASA Astrophysics Data System (ADS)

    Bennett, Scott E. K.; Oskin, Michael E.; Iriondo, Alexander

    2017-11-01

    Details about the timing and kinematics of rifting are crucial to understand the conditions that led to strain localization, continental rupture, and formation of the Gulf of California ocean basin. We integrate detailed geologic and structural mapping, basin analysis, and geochronology to characterize transtensional rifting on northeastern Isla Tiburón, a proximal onshore exposure of the rifted North America margin, adjacent to the axis of the Gulf of California. Slip on the Kunkaak normal fault tilted its hanging wall down-to-the-east 70° and formed the non-marine Tecomate basin, deposited across a 20° angular unconformity. From 7.1-6.4 Ma, the hanging wall tilted at 35 ± 5°/Myr, while non-marine sandstone and conglomerate accumulated at 1.4 ± 0.2 mm/yr. At least 1.8 ± 0.1 km of sediments and pyroclastic deposits accumulated in the Tecomate basin concurrent with clockwise vertical-axis block rotation and 2.8 km of total dip-slip motion on the Kunkaak fault. Linear extrapolation of tilting and sedimentation rates suggests that faulting and basin deposition initiated 7.6-7.4 Ma, but an older history involving initially slower rates is permissible. The Kunkaak fault and Tecomate basin are truncated by NW-striking, dextral-oblique structures, including the Yawassag fault, which accrued > 8 km of post-6.4 Ma dextral displacement. The Coastal Sonora fault zone on mainland Sonora, which accrued several tens of kilometers of late Miocene dextral offset, continues to the northwest, across northeastern Isla Tiburón and offshore into the Gulf of California. The establishment of rapid, latest Miocene transtension in the Coastal Sonora fault zone was synchronous with the 8-7 Ma onset of transform faulting and basin formation along the nascent Pacific-North America plate boundary throughout northwestern Mexico and southern California. Plate boundary strain localized into this Gulf of California shear zone, a narrow transtensional belt that subsequently hosted the marine incursion and continental rupture in the Gulf of California.

  15. The environmental contaminant tributyltin leads to abnormalities in different levels of the hypothalamus-pituitary-thyroid axis in female rats.

    PubMed

    Andrade, Marcelle Novaes; Santos-Silva, Ana Paula; Rodrigues-Pereira, Paula; Paiva-Melo, Francisca Diana; de Lima Junior, Niedson Correa; Teixeira, Mariana Pires; Soares, Paula; Dias, Glaecir Roseni Munstock; Graceli, Jones Bernardes; de Carvalho, Denise Pires; Ferreira, Andrea Claudia Freitas; Miranda-Alves, Leandro

    2018-06-11

    Tributyltin is a biocide used in nautical paints, aiming to reduce fouling of barnacles in ships. Despite the fact that many effects of TBT on marine species are known, studies in mammals have been limited, especially those evaluating its effect on the function of the hypothalamus-pituitary-thyroid (HPT) axis. The aim of this study was to investigate the effects of subchronic exposure to TBT on the HPT axis in female rats. Female Wistar rats received vehicle, TBT 200 ng kg -1 BW d -1 or 1000 ng kg -1 BW d -1 orally by gavage for 40 d. Hypothalamus, pituitary, thyroid, liver and blood samples were collected. TBT200 and TBT1000 thyroids showed vacuolated follicular cells, with follicular hypertrophy and hyperplasia. An increase in epithelial height and a decrease in the thyroid follicle and colloid area were observed in TBT1000 rats. Moreover, an increase in the epithelium/colloid area ratio was observed in both TBT groups. Lower TRH mRNA expression was observed in the hypothalami of TBT200 and TBT1000 rats. An increase in Dio1 mRNA levels was observed in the hypothalamus and thyroid in TBT1000 rats only. TSH serum levels were increased in TBT200 rats. In TBT1000 rats, there was a decrease in total T4 serum levels compared to control rats, whereas T3 serum levels did not show significant alterations. We conclude that TBT exposure can promote critical abnormalities in the HPT axis, including changes in TRH mRNA expression and serum TSH and T4 levels, in addition to affecting thyroid morphology. These findings demonstrate that TBT disrupts the HPT axis. Additionally, the changes found in thyroid hormones suggest that TBT may interfere with the peripheral metabolism of these hormones, an idea corroborated by the observed changes in Dio1 mRNA levels. Therefore, TBT exposition might interfere not only with the thyroid axis but also with thyroid hormone metabolism. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Marines in the Boxer Rebellion as a Model for Current Marine Corps Operations

    DTIC Science & Technology

    2016-06-10

    several days traveling with me and helping me get around in China. Additionally, the leadership and instructors at Staff Group 7 have been very...Security Group ....................................................................... 45 Marine Corps Operations during the Cold War...and removing the foreigners.33 The Boxers were a loosely organized group with no single leader. Although the Chinese Imperial Army would usually

  17. Marine Renewable Energy: Resource Characterization and Physical Effects

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

    Yang, Zhaoqing; Copping, Andrea E.

    This complete reference to marine renewable energy covers aspects of resource characterization and physical effects of harvesting the ocean’s vast and powerful resources—from wave and tidal stream to ocean current energy. Experts in each of these areas contribute their insights to provide a cohesive overview of the marine renewable energy spectrum based on theoretical, numerical modeling, and field-measurement approaches.

  18. Marine Biology and Oceanography, Grades Nine to Twelve. Part I.

    ERIC Educational Resources Information Center

    Kolb, James A.

    This unit, one of a series designed to develop and foster an understanding of the marine environment, presents marine science activities for students in grades 9-12. The unit, focusing on physical factors influencing life in the sea, is divided into sections dealing with: (1) the ocean floor; (2) tides; (3) ocean waves; (4) ocean currents; (5)…

  19. Cumulative Human Impacts on Mediterranean and Black Sea Marine Ecosystems: Assessing Current Pressures and Opportunities

    PubMed Central

    Micheli, Fiorenza; Halpern, Benjamin S.; Walbridge, Shaun; Ciriaco, Saul; Ferretti, Francesco; Fraschetti, Simonetta; Lewison, Rebecca; Nykjaer, Leo; Rosenberg, Andrew A.

    2013-01-01

    Management of marine ecosystems requires spatial information on current impacts. In several marine regions, including the Mediterranean and Black Sea, legal mandates and agreements to implement ecosystem-based management and spatial plans provide new opportunities to balance uses and protection of marine ecosystems. Analyses of the intensity and distribution of cumulative impacts of human activities directly connected to the ecological goals of these policy efforts are critically needed. Quantification and mapping of the cumulative impact of 22 drivers to 17 marine ecosystems reveals that 20% of the entire basin and 60–99% of the territorial waters of EU member states are heavily impacted, with high human impact occurring in all ecoregions and territorial waters. Less than 1% of these regions are relatively unaffected. This high impact results from multiple drivers, rather than one individual use or stressor, with climatic drivers (increasing temperature and UV, and acidification), demersal fishing, ship traffic, and, in coastal areas, pollution from land accounting for a majority of cumulative impacts. These results show that coordinated management of key areas and activities could significantly improve the condition of these marine ecosystems. PMID:24324585

  20. Investigation of heavy current discharges with high initial gas density

    NASA Astrophysics Data System (ADS)

    Budin, A.; Bogomaz, A.; Kolikov, V.; Kuprin, A.; Leontiev, V.; Rutberg, Ph.; Shirokov, N.

    1996-05-01

    Piezoelectric pressure transducers, with noise immunity and time resolution of 0,5 μs were used to measure pulse pressures of 430 MPa along the axis of an electrical discharge channel. Initial concentration of He was 2,7ṡ1021cm-3, dI/dt=6ṡ1011 A/s, and Imax=560 kA. Shock waves with amplitudes exceeding the pressure along the axis, were detected by a pressure transducer on the wall of the discharge chamber. Typical shock velocities were 2ṡ4 km/s. Average pressure measurements along the discharge axis at different radii were used to estimate the current density distribution along the canal radius. The presence of the shock waves, promoting the additional hydrogen heating in the discharge chamber, has been registered during the discharge in hydrogen for Imax˜1 MA and an initial concentration of 1021cm-3.

  1. Sexual orientation disparities in mental health: the moderating role of educational attainment.

    PubMed

    Barnes, David M; Hatzenbuehler, Mark L; Hamilton, Ava D; Keyes, Katherine M

    2014-09-01

    Mental health disparities between sexual minorities and heterosexuals remain inadequately understood, especially across levels of educational attainment. The purpose of the present study was to test whether education modifies the association between sexual orientation and mental disorder. We compared the odds of past 12-month and lifetime psychiatric disorder prevalence (any Axis-I, any mood, any anxiety, any substance use, and comorbidity) between lesbian, gay, and bisexual (LGB) and heterosexual individuals by educational attainment (those with and without a bachelor's degree), adjusting for covariates, and tested for interaction between sexual orientation and educational attainment. Data are drawn from the National Epidemiologic Survey on Alcohol and Related Conditions, a nationally representative survey of non-institutionalized US adults (N = 34,653; 577 LGB). Sexual orientation disparities in mental health are smaller among those with a college education. Specifically, the disparity in those with versus those without a bachelor's degree was attenuated by 100 % for any current mood disorder, 82 % for any current Axis-I disorder, 76 % for any current anxiety disorder, and 67 % for both any current substance use disorder and any current comorbidity. Further, the interaction between sexual orientation and education was statistically significant for any current Axis-I disorder, any current mood disorder, and any current anxiety disorder. Our findings for lifetime outcomes were similar. The attenuated mental health disparity at higher education levels underscores the particular risk for disorder among LGBs with less education. Future studies should consider selection versus causal factors to explain the attenuated disparity we found at higher education levels.

  2. Bioindicators for monitoring marine litter ingestion and its impacts on Mediterranean biodiversity.

    PubMed

    Fossi, Maria Cristina; Pedà, Cristina; Compa, Montserrat; Tsangaris, Catherine; Alomar, Carme; Claro, Francoise; Ioakeimidis, Christos; Galgani, Francois; Hema, Tatjana; Deudero, Salud; Romeo, Teresa; Battaglia, Pietro; Andaloro, Franco; Caliani, Ilaria; Casini, Silvia; Panti, Cristina; Baini, Matteo

    2018-06-01

    The Mediterranean Sea has been described as one of the most affected areas by marine litter in the world. Although effects on organisms from marine plastic litter ingestion have been investigated in several oceanic areas, there is still a lack of information from the Mediterranean Sea. The main objectives of this paper are to review current knowledge on the impact of marine litter on Mediterranean biodiversity, to define selection criteria for choosing marine organisms suitable for use as bioindicator species, and to propose a methodological approach to assessing the harm related to marine litter ingestion in several Mediterranean habitats and sub-regions. A new integrated monitoring tool that would provide the information necessary to design and implement future mitigation actions in the Mediterranean basin is proposed. According to bibliographic research and statistical analysis on current knowledge of marine litter ingestion, the area of the Mediterranean most studied, in terms of number of species and papers in the Mediterranean Sea is the western sub-area as well as demersal (32.9%) and pelagic (27.7%) amongst habitats. Applying ecological and biological criteria to the most threatened species obtained by statistical analysis, bioindicator species for different habitats and monitoring scale were selected. A threefold approach, simultaneously measuring the presence and effects of plastic, can provide the actual harm and sub-lethal effects to organisms caused by marine litter ingestion. The research revealed gaps in knowledge, and this paper suggests measures to close the gap. This and the selection of appropriate bioindicator species would represent a step forward for marine litter risk assessment, and the implementation of future actions and mitigation measures for specific Mediterranean areas, habitats and species affected by marine litter ingestion. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Towards a meaningful assessment of marine ecological impacts in life cycle assessment (LCA).

    PubMed

    Woods, John S; Veltman, Karin; Huijbregts, Mark A J; Verones, Francesca; Hertwich, Edgar G

    2016-01-01

    Human demands on marine resources and space are currently unprecedented and concerns are rising over observed declines in marine biodiversity. A quantitative understanding of the impact of industrial activities on the marine environment is thus essential. Life cycle assessment (LCA) is a widely applied method for quantifying the environmental impact of products and processes. LCA was originally developed to assess the impacts of land-based industries on mainly terrestrial and freshwater ecosystems. As such, impact indicators for major drivers of marine biodiversity loss are currently lacking. We review quantitative approaches for cause-effect assessment of seven major drivers of marine biodiversity loss: climate change, ocean acidification, eutrophication-induced hypoxia, seabed damage, overexploitation of biotic resources, invasive species and marine plastic debris. Our review shows that impact indicators can be developed for all identified drivers, albeit at different levels of coverage of cause-effect pathways and variable levels of uncertainty and spatial coverage. Modeling approaches to predict the spatial distribution and intensity of human-driven interventions in the marine environment are relatively well-established and can be employed to develop spatially-explicit LCA fate factors. Modeling approaches to quantify the effects of these interventions on marine biodiversity are less well-developed. We highlight specific research challenges to facilitate a coherent incorporation of marine biodiversity loss in LCA, thereby making LCA a more comprehensive and robust environmental impact assessment tool. Research challenges of particular importance include i) incorporation of the non-linear behavior of global circulation models (GCMs) within an LCA framework and ii) improving spatial differentiation, especially the representation of coastal regions in GCMs and ocean-carbon cycle models. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. The high-β{sub N} hybrid scenario for ITER and FNSF steady-state missions

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

    Turco, F.; Petty, C. C.; Luce, T. C.

    2015-05-15

    New experiments on DIII-D have demonstrated the steady-state potential of the hybrid scenario, with 1 MA of plasma current driven fully non-inductively and β{sub N} up to 3.7 sustained for ∼3 s (∼1.5 current diffusion time, τ{sub R}, in DIII-D), providing the basis for an attractive option for steady-state operation in ITER and FNSF. Excellent confinement is achieved (H{sub 98y2} ∼ 1.6) without performance limiting tearing modes. The hybrid regime overcomes the need for off-axis current drive efficiency, taking advantage of poloidal magnetic flux pumping that is believed to be the result of a saturated 3/2 tearing mode. This allows for efficient currentmore » drive close to the axis, without deleterious sawtooth instabilities. In these experiments, the edge surface loop voltage is driven down to zero for >1 τ{sub R} when the poloidal β is increased above 1.9 at a plasma current of 1.0 MA and the ECH power is increased to 3.2 MW. Stationary operation of hybrid plasmas with all on-axis current drive is sustained at pressures slightly above the ideal no-wall limit, while the calculated ideal with-wall MHD limit is β{sub N} ∼ 4–4.5. Off-axis Neutral Beam Injection (NBI) power has been used to broaden the pressure and current profiles in this scenario, seeking to take advantage of higher predicted kink stability limits and lower values of the tearing stability index Δ′, as calculated by the DCON and PEST3 codes. Results based on measured profiles predict ideal limits at β{sub N} > 4.5, 10% higher than the cases with on-axis NBI. A 0-D model, based on the present confinement, β{sub N} and shape values of the DIII-D hybrid scenario, shows that these plasmas are consistent with the ITER 9 MA, Q = 5 mission and the FNSF 6.7 MA scenario with Q = 3.5. With collisionality and edge safety factor values comparable to those envisioned for ITER and FNSF, the high-β{sub N} hybrid represents an attractive high performance option for the steady-state missions of these devices.« less

  5. Determination of crack depth in aluminum using eddy currents and GMR sensors

    NASA Astrophysics Data System (ADS)

    Lopes Ribeiro, A.; Pasadas, D.; Ramos, H. G.; Rocha, T.

    2015-03-01

    In this paper we use eddy currents to determine the depth of linear cracks in aluminum plates. A constant field probe is used to generate the spatially uniform excitation field and a single axis giant magneto-resistor (GMR) sensor is used to measure the eddy currents magnetic field. Different depths were machined in one aluminum plate with 4 mm of thickness. By scanning those cracks the magnetic field components parallel and perpendicular to the crack's line were measured when the eddy currents were launched perpendicularly to the crack's line. To characterize one crack in a plate of a given thickness and material, the experimental procedure was defined. The plate surface is scanned to detect and locate one crack. The acquired data enables the determination of the crack's length and orientation. A second scanning is performed with the excitation current perpendicular to the crack and the GMR sensing axis perpendicular and parallel to the crack's line.

  6. Database documentation of marine mammal stranding and mortality: current status review and future prospects.

    PubMed

    Chan, Derek K P; Tsui, Henry C L; Kot, Brian C W

    2017-11-21

    Databases are systematic tools to archive and manage information related to marine mammal stranding and mortality events. Stranding response networks, governmental authorities and non-governmental organizations have established regional or national stranding networks and have developed unique standard stranding response and necropsy protocols to document and track stranded marine mammal demographics, signalment and health data. The objectives of this study were to (1) describe and review the current status of marine mammal stranding and mortality databases worldwide, including the year established, types of database and their goals; and (2) summarize the geographic range included in the database, the number of cases recorded, accessibility, filter and display methods. Peer-reviewed literature was searched, focussing on published databases of live and dead marine mammal strandings and mortality and information released from stranding response organizations (i.e. online updates, journal articles and annual stranding reports). Databases that were not published in the primary literature or recognized by government agencies were excluded. Based on these criteria, 10 marine mammal stranding and mortality databases were identified, and strandings and necropsy data found in these databases were evaluated. We discuss the results, limitations and future prospects of database development. Future prospects include the development and application of virtopsy, a new necropsy investigation tool. A centralized web-accessed database of all available postmortem multimedia from stranded marine mammals may eventually support marine conservation and policy decisions, which will allow the use of marine animals as sentinels of ecosystem health, working towards a 'One Ocean-One Health' ideal.

  7. Marine Planning for Potential Wave Energy Facility Placement Amongst a Crowded Sea of Existing Resource Uses

    NASA Astrophysics Data System (ADS)

    Feist, B. E.; Fuller, E.; Plummer, M. L.

    2016-12-01

    Conversion to renewable energy sources is a logical response to increasing pressure to reduce greenhouse gas emissions. Ocean wave energy is the least developed renewable energy source, despite having the highest energy per unit area. While many hurdles remain in developing wave energy, assessing potential conflicts and evaluating tradeoffs with existing uses is essential. Marine planning encompasses a broad array of activities that take place in and affect large marine ecosystems, making it an ideal tool for evaluating wave energy resource use conflicts. In this study, we focus on the potential conflicts between wave energy conversion (WEC) facilities and existing marine uses in the context of marine planning, within the California Current Large Marine Ecosystem. First, we evaluated wave energy facility development using the Wave Energy Model (WEM) of the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) toolkit. Second, we ran spatial analyses on model output to identify conflicts with existing marine uses including AIS based vessel traffic, VMS and observer based measures of commercial fishing effort, and marine conservation areas. We found that regions with the highest wave energy potential were distant from major cities and that infrastructure limitations (cable landing sites) restrict integration with existing power grids. We identified multiple spatial conflicts with existing marine uses; especially shipping vessels and various commercial fishing fleets, and overlap with marine conservation areas varied by conservation designation. While wave energy generation facilities may be economically viable in the California Current, this viability must be considered within the context of the costs associated with conflicts that arise with existing marine uses. Our analyses can be used to better inform placement of WEC devices (as well as other types of renewable energy facilities) in the context of marine planning by accounting for economic tradeoffs and providing spatially explicit site prioritization.

  8. Designing connected marine reserves in the face of global warming.

    PubMed

    Álvarez-Romero, Jorge G; Munguía-Vega, Adrián; Beger, Maria; Del Mar Mancha-Cisneros, Maria; Suárez-Castillo, Alvin N; Gurney, Georgina G; Pressey, Robert L; Gerber, Leah R; Morzaria-Luna, Hem Nalini; Reyes-Bonilla, Héctor; Adams, Vanessa M; Kolb, Melanie; Graham, Erin M; VanDerWal, Jeremy; Castillo-López, Alejandro; Hinojosa-Arango, Gustavo; Petatán-Ramírez, David; Moreno-Baez, Marcia; Godínez-Reyes, Carlos R; Torre, Jorge

    2018-02-01

    Marine reserves are widely used to protect species important for conservation and fisheries and to help maintain ecological processes that sustain their populations, including recruitment and dispersal. Achieving these goals requires well-connected networks of marine reserves that maximize larval connectivity, thus allowing exchanges between populations and recolonization after local disturbances. However, global warming can disrupt connectivity by shortening potential dispersal pathways through changes in larval physiology. These changes can compromise the performance of marine reserve networks, thus requiring adjusting their design to account for ocean warming. To date, empirical approaches to marine prioritization have not considered larval connectivity as affected by global warming. Here, we develop a framework for designing marine reserve networks that integrates graph theory and changes in larval connectivity due to potential reductions in planktonic larval duration (PLD) associated with ocean warming, given current socioeconomic constraints. Using the Gulf of California as case study, we assess the benefits and costs of adjusting networks to account for connectivity, with and without ocean warming. We compare reserve networks designed to achieve representation of species and ecosystems with networks designed to also maximize connectivity under current and future ocean-warming scenarios. Our results indicate that current larval connectivity could be reduced significantly under ocean warming because of shortened PLDs. Given the potential changes in connectivity, we show that our graph-theoretical approach based on centrality (eigenvector and distance-weighted fragmentation) of habitat patches can help design better-connected marine reserve networks for the future with equivalent costs. We found that maintaining dispersal connectivity incidentally through representation-only reserve design is unlikely, particularly in regions with strong asymmetric patterns of dispersal connectivity. Our results support previous studies suggesting that, given potential reductions in PLD due to ocean warming, future marine reserve networks would require more and/or larger reserves in closer proximity to maintain larval connectivity. © 2017 John Wiley & Sons Ltd.

  9. New agents modulating the renin-angiotensin-aldosterone system—Will there be a new therapeutic option?

    PubMed Central

    Szoka, Piotr; Kolodziejczyk, Patrycjusz; Kramkowski, Karol; Wojewodzka-Zelezniakowicz, Marzena; Chabielska, Ewa

    2016-01-01

    The renin-angiotensin-aldosterone system (RAAS) is more complex than it was originally regarded. According to the current subject knowledge, there are two main axes of the RAAS: (1) angiotensin-converting enzyme (ACE)-angiotensin II-AT1 receptor axis and (2) ACE2-angiotensin-(1-7)-Mas receptor axis. The activation of the first axis leads to deleterious effects, including vasoconstriction, endothelial dysfunction, thrombosis, inflammation, and fibrosis; therefore, blocking the components of this axis is a highly rational and commonly used therapeutic procedure. The ACE2-Ang-(1-7)-Mas receptor axis has a different role, since it often opposes the effects induced by the classical ACE-Ang II-AT1 axis. Once the positive effects of the ACE2-Ang-(1-7)-Mas axis were discovered, the alternative ways of pharmacotherapy activating this axis of RAAS appeared. This article briefly describes new molecules affecting the RAAS, namely: recombinant human ACE2, ACE2 activators, angiotensin-(1-7) peptide and non-peptide analogs, aldosterone synthase inhibitors, and the third and fourth generation of mineralocorticoid receptor antagonists. The results of the experimental and clinical studies are encouraging, which leads us to believe that these new molecules can support the treatment of cardiovascular diseases as well as cardiometabolic disorders. PMID:27439538

  10. Mine-hunting dolphins of the Navy

    NASA Astrophysics Data System (ADS)

    Moore, Patrick W.

    1997-07-01

    Current counter-mine and obstacle avoidance technology is inadequate, and limits the Navy's capability to conduct shallow water (SW) and very shallow water (VSW) MCM in support of beach assaults by Marine Corps forces. Without information as to the location or density of mined beach areas, it must be assumed that if mines are present in one area then they are present in all areas. Marine mammal systems (MMS) are an unusual, effective and unique solution to current problems of mine and obstacle hunting. In the US Navy Mine Warfare Plan for 1994-1995 Marine Mammal Systems are explicitly identified as the Navy's only means of countering buried mines and the best means for dealing with close-tethered mines. The dolphins in these systems possess a biological sonar specifically adapted for their shallow and very shallow water habitat. Research has demonstrated that the dolphin biosonar outperforms any current hardware system available for SW and VSW applications. This presentation will cover current Fleet MCM systems and future technology application to the littoral region.

  11. Steady-state configuration and tension calculations of marine cables under complex currents via separated particle swarm optimization

    NASA Astrophysics Data System (ADS)

    Xu, Xue-song

    2014-12-01

    Under complex currents, the motion governing equations of marine cables are complex and nonlinear, and the calculations of cable configuration and tension become difficult compared with those under the uniform or simple currents. To obtain the numerical results, the usual Newton-Raphson iteration is often adopted, but its stability depends on the initial guessed solution to the governing equations. To improve the stability of numerical calculation, this paper proposed separated the particle swarm optimization, in which the variables are separated into several groups, and the dimension of search space is reduced to facilitate the particle swarm optimization. Via the separated particle swarm optimization, these governing nonlinear equations can be solved successfully with any initial solution, and the process of numerical calculation is very stable. For the calculations of cable configuration and tension of marine cables under complex currents, the proposed separated swarm particle optimization is more effective than the other particle swarm optimizations.

  12. An evaluation of improved structural materials in marine piling.

    DOT National Transportation Integrated Search

    1980-11-01

    A study to evaluate the production and field performance of marine piling fabricated with improved structural materials is currently being performed by the Oregon State Highway Division under the sponsorship of the Federal Highway Administration. In ...

  13. Developments in Marine Current Turbine Research at the United States Naval Academy (Invited)

    NASA Astrophysics Data System (ADS)

    Flack, K. A.; Luznik, L.

    2013-12-01

    A series of tests have been performed on a 1/25th scale model of a two bladed horizontal axis marine current turbine. The tests were conducted in a large tow tank facility at the United States Naval Academy. The turbine model has a 0.8 m diameter (D) rotor with a NACA 63-618 cross section, which is Reynolds number independent with respect to the lift coefficient in the operating range of Rec ≈ 4 x 105. Baseline test were conducted to obtain torque, thrust and rotational speed at a range of tip speed ratios (TSR) from 5 < TSR < 11. The power and thrust coefficients for the model turbine match expected results from blade-element-momentum theory. The lift and drag curves for the numerical model were obtained by testing a 2D NACA 63-618 airfoil in a wind tunnel. Additional tests were performed at two rotor depths (1.3D and 2.25D) in the presence of intermediate and deep water waves. The average values for power and thrust coefficient are weakly dependent on turbine depth. The waves yield a small increase in turbine performance which can be explained by Stokes drift velocity. Phase averaged results indicate that the oscillatory wave velocity results in significant variations in measured turbine torque and rotational speed as a function of wave phase. The turbine rotation speed, power, and thrust reach a maximum with the passing of the wave crest and a minimum with the passing of the wave trough. The torque appears dependent on vertical velocity, which lags the horizontal velocity by 90° of wave phase. Variations of the performance parameters are of the same order of magnitude as the average value, especially when the turbine is near the mean free surface and in the presence of high energy waves. These results demonstrate the impact of surface gravity waves on power production and structural loading. Future tests will focus on measuring and modeling the wake of the turbine for unsteady flow conditions. Model Turbine Power Coefficient vs, Tip Speed Ratio

  14. Institutional Mapping Towards Developing a Framework for Sustainable Marine Spatial Planning

    NASA Astrophysics Data System (ADS)

    Yatim, M. H. M.; Omar, A. H.; Abdullah, N. M.; Hashim, N. M.

    2016-09-01

    Within few years before, the urge to implement the marine spatial planning is due to increasing numbers of marine activities that will lead into uncertainties of rights, restrictions and responsibilities of the maritime nations. Marine authorities in this situation that deal with national rights and legislations are the government institutions that engage with marine spatial information. There are several elements to be considered when dealing with the marine spatial planning; which is institutional sustainability governance. Providing the importance of marine spatial planning towards sustainable marine spatial governance, the focus should highlight the role marine institutions towards sustainable marine plan. The iterative process of marine spatial planning among marine institutions is important as the spatial information governance is scattered from reflected rights, restrictions and responsibilities of marine government institutions. Malaysia is one of the maritime nations that conjures the initial step towards establishing the sustainable marine spatial planning. In order to have sustainable institutions in marine spatial planning process, it involves four main stages; planning phase, plan evaluation phase, implementation phase and post implementation phase. Current situation has witnessed the unclear direction and role of marine government institutions to manage the marine spatial information. This review paper is focusing on the institutional sustainability upon interaction of marine government institutions in the marine spatial planning process based on Institutional Analysis Framework. The outcome of the integration of institutional sustainability and marine spatial planning process will propose a framework of marine institutional sustainable plan.

  15. Seabird diversity hotspot linked to ocean productivity in the Canary Current Large Marine Ecosystem

    PubMed Central

    Attrill, Martin J.; Becker, Peter H.; Egevang, Carsten; Furness, Robert W.; Grémillet, David; Kopp, Matthias; Lescroël, Amélie; Matthiopoulos, Jason; Peter, Hans-Ulrich; Phillips, Richard A.

    2016-01-01

    Upwelling regions are highly productive habitats targeted by wide-ranging marine predators and industrial fisheries. In this study, we track the migratory movements of eight seabird species from across the Atlantic; quantify overlap with the Canary Current Large Marine Ecosystem (CCLME) and determine the habitat characteristics that drive this association. Our results indicate the CCLME is a biodiversity hotspot for migratory seabirds; all tracked species and more than 70% of individuals used this upwelling region. Relative species richness peaked in areas where sea surface temperature averaged between 15 and 20°C, and correlated positively with chlorophyll a, revealing the optimum conditions driving bottom-up trophic effects for seabirds. Marine vertebrates are not confined by international boundaries, making conservation challenging. However, by linking diversity to ocean productivity, our research reveals the significance of the CCLME for seabird populations from across the Atlantic, making it a priority for conservation action. PMID:27531154

  16. Seabird diversity hotspot linked to ocean productivity in the Canary Current Large Marine Ecosystem.

    PubMed

    Grecian, W James; Witt, Matthew J; Attrill, Martin J; Bearhop, Stuart; Becker, Peter H; Egevang, Carsten; Furness, Robert W; Godley, Brendan J; González-Solís, Jacob; Grémillet, David; Kopp, Matthias; Lescroël, Amélie; Matthiopoulos, Jason; Patrick, Samantha C; Peter, Hans-Ulrich; Phillips, Richard A; Stenhouse, Iain J; Votier, Stephen C

    2016-08-01

    Upwelling regions are highly productive habitats targeted by wide-ranging marine predators and industrial fisheries. In this study, we track the migratory movements of eight seabird species from across the Atlantic; quantify overlap with the Canary Current Large Marine Ecosystem (CCLME) and determine the habitat characteristics that drive this association. Our results indicate the CCLME is a biodiversity hotspot for migratory seabirds; all tracked species and more than 70% of individuals used this upwelling region. Relative species richness peaked in areas where sea surface temperature averaged between 15 and 20°C, and correlated positively with chlorophyll a, revealing the optimum conditions driving bottom-up trophic effects for seabirds. Marine vertebrates are not confined by international boundaries, making conservation challenging. However, by linking diversity to ocean productivity, our research reveals the significance of the CCLME for seabird populations from across the Atlantic, making it a priority for conservation action. © 2016 The Authors.

  17. The Emperor’s New Clothes -- SF Force Structure and EAF Force Protection

    DTIC Science & Technology

    2002-07-01

    Competencies.129 USAF Major Commands and Wings should develop supporting Mission Essential Task Lists tailored to their specific situation. Outsourcing ...United States Marine Corps Command and Staff College Marine Corps University 2076 South Street Marine Corps Combat Development Command Quantico...Within current resource constraints, some present SF functions must be outsourced or reassigned, other present functions must be expanded, and some

  18. Drugs and Cosmetics from the Sea

    PubMed Central

    Kijjoa, Anake; Sawangwong, Pichan

    2004-01-01

    The marine environment is a rich source of both biological and chemical diversity. This diversity has been the source of unique chemical compounds with the potential for industrial development as pharmaceuticals, cosmetics, nutritional supplements, molecular probes, fine chemicals and agrochemicals. In recent years, a significant number of novel metabolites with potent pharmacological properties has been discovered from the marine organisms. Although there are only a few marine-derived products currently on the market, several robust new compounds derived from marine natural products are now in the clinical pipeline, with more clinical development. While the marine world offers an extremely rich resource for novel compounds, it also represents a great challenge that requires inputs from various scientific areas to bring the marine chemical diversity up to its therapeutic potential.

  19. Measurement of the νμ charged current quasielastic cross section on carbon with the T2K on-axis neutrino beam

    NASA Astrophysics Data System (ADS)

    Abe, K.; Adam, J.; Aihara, H.; Andreopoulos, C.; Aoki, S.; Ariga, A.; Assylbekov, S.; Autiero, D.; Barbi, M.; Barker, G. J.; Barr, G.; Bartet-Friburg, P.; Bass, M.; Batkiewicz, M.; Bay, F.; Berardi, V.; Berger, B. E.; Berkman, S.; Bhadra, S.; Blaszczyk, F. d. M.; Blondel, A.; Bolognesi, S.; Bordoni, S.; Boyd, S. B.; Brailsford, D.; Bravar, A.; Bronner, C.; Buchanan, N.; Calland, R. G.; Caravaca Rodríguez, J.; Cartwright, S. L.; Castillo, R.; Catanesi, M. G.; Cervera, A.; Cherdack, D.; Chikuma, N.; Christodoulou, G.; Clifton, A.; Coleman, J.; Coleman, S. J.; Collazuol, G.; Connolly, K.; Cremonesi, L.; Dabrowska, A.; Danko, I.; Das, R.; Davis, S.; de Perio, P.; De Rosa, G.; Dealtry, T.; Dennis, S. R.; Densham, C.; Dewhurst, D.; Di Lodovico, F.; Di Luise, S.; Dolan, S.; Drapier, O.; Duffy, K.; Dumarchez, J.; Dytman, S.; Dziewiecki, M.; Emery-Schrenk, S.; Ereditato, A.; Escudero, L.; Ferchichi, C.; Feusels, T.; Finch, A. J.; Fiorentini, G. A.; Friend, M.; Fujii, Y.; Fukuda, Y.; Furmanski, A. P.; Galymov, V.; Garcia, A.; Giffin, S.; Giganti, C.; Gilje, K.; Goeldi, D.; Golan, T.; Gonin, M.; Grant, N.; Gudin, D.; Hadley, D. R.; Haegel, L.; Haesler, A.; Haigh, M. D.; Hamilton, P.; Hansen, D.; Hara, T.; Hartz, M.; Hasegawa, T.; Hastings, N. C.; Hayashino, T.; Hayato, Y.; Hearty, C.; Helmer, R. L.; Hierholzer, M.; Hignight, J.; Hillairet, A.; Himmel, A.; Hiraki, T.; Hirota, S.; Holeczek, J.; Horikawa, S.; Hosomi, F.; Huang, K.; Ichikawa, A. K.; Ieki, K.; Ieva, M.; Ikeda, M.; Imber, J.; Insler, J.; Irvine, T. J.; Ishida, T.; Ishii, T.; Iwai, E.; Iwamoto, K.; Iyogi, K.; Izmaylov, A.; Jacob, A.; Jamieson, B.; Jiang, M.; Johnson, S.; Jo, J. H.; Jonsson, P.; Jung, C. K.; Kabirnezhad, M.; Kaboth, A. C.; Kajita, T.; Kakuno, H.; Kameda, J.; Kanazawa, Y.; Karlen, D.; Karpikov, I.; Katori, T.; Kearns, E.; Khabibullin, M.; Khotjantsev, A.; Kielczewska, D.; Kikawa, T.; Kilinski, A.; Kim, J.; King, S.; Kisiel, J.; Kitching, P.; Kobayashi, T.; Koch, L.; Koga, T.; Kolaceke, A.; Konaka, A.; Kopylov, A.; Kormos, L. L.; Korzenev, A.; Koshio, Y.; Kropp, W.; Kubo, H.; Kudenko, Y.; Kurjata, R.; Kutter, T.; Lagoda, J.; Lamont, I.; Larkin, E.; Laveder, M.; Lawe, M.; Lazos, M.; Lindner, T.; Lister, C.; Litchfield, R. P.; Longhin, A.; Lopez, J. P.; Ludovici, L.; Magaletti, L.; Mahn, K.; Malek, M.; Manly, S.; Marino, A. D.; Marteau, J.; Martin, J. F.; Martins, P.; Martynenko, S.; Maruyama, T.; Matveev, V.; Mavrokoridis, K.; Mazzucato, E.; McCarthy, M.; McCauley, N.; McFarland, K. S.; McGrew, C.; Mefodiev, A.; Metelko, C.; Mezzetto, M.; Mijakowski, P.; Miller, C. A.; Minamino, A.; Mineev, O.; Missert, A.; Miura, M.; Moriyama, S.; Mueller, Th. A.; Murakami, A.; Murdoch, M.; Murphy, S.; Myslik, J.; Nakadaira, T.; Nakahata, M.; Nakamura, K. G.; Nakamura, K.; Nakayama, S.; Nakaya, T.; Nakayoshi, K.; Nantais, C.; Nielsen, C.; Nirkko, M.; Nishikawa, K.; Nishimura, Y.; Nowak, J.; O'Keeffe, H. M.; Ohta, R.; Okumura, K.; Okusawa, T.; Oryszczak, W.; Oser, S. M.; Ovsyannikova, T.; Owen, R. A.; Oyama, Y.; Palladino, V.; Palomino, J. L.; Paolone, V.; Payne, D.; Perevozchikov, O.; Perkin, J. D.; Petrov, Y.; Pickard, L.; Pinzon Guerra, E. S.; Pistillo, C.; Plonski, P.; Poplawska, E.; Popov, B.; Posiadala-Zezula, M.; Poutissou, J.-M.; Poutissou, R.; Przewlocki, P.; Quilain, B.; Radicioni, E.; Ratoff, P. N.; Ravonel, M.; Rayner, M. A. M.; Redij, A.; Reeves, M.; Reinherz-Aronis, E.; Riccio, C.; Rodrigues, P. A.; Rojas, P.; Rondio, E.; Roth, S.; Rubbia, A.; Ruterbories, D.; Rychter, A.; Sacco, R.; Sakashita, K.; Sánchez, F.; Sato, F.; Scantamburlo, E.; Scholberg, K.; Schoppmann, S.; Schwehr, J.; Scott, M.; Seiya, Y.; Sekiguchi, T.; Sekiya, H.; Sgalaberna, D.; Shah, R.; Shaker, F.; Shaw, D.; Shiozawa, M.; Short, S.; Shustrov, Y.; Sinclair, P.; Smith, B.; Smy, M.; Sobczyk, J. T.; Sobel, H.; Sorel, M.; Southwell, L.; Stamoulis, P.; Steinmann, J.; Still, B.; Suda, Y.; Suzuki, A.; Suzuki, K.; Suzuki, S. Y.; Suzuki, Y.; Tacik, R.; Tada, M.; Takahashi, S.; Takeda, A.; Takeuchi, Y.; Tanaka, H. K.; Tanaka, H. A.; Tanaka, M. M.; Terhorst, D.; Terri, R.; Thompson, L. F.; Thorley, A.; Tobayama, S.; Toki, W.; Tomura, T.; Totsuka, Y.; Touramanis, C.; Tsukamoto, T.; Tzanov, M.; Uchida, Y.; Vacheret, A.; Vagins, M.; Vasseur, G.; Wachala, T.; Wakamatsu, K.; Walter, C. W.; Wark, D.; Warzycha, W.; Wascko, M. O.; Weber, A.; Wendell, R.; Wilkes, R. J.; Wilking, M. J.; Wilkinson, C.; Williamson, Z.; Wilson, J. R.; Wilson, R. J.; Wongjirad, T.; Yamada, Y.; Yamamoto, K.; Yanagisawa, C.; Yano, T.; Yen, S.; Yershov, N.; Yokoyama, M.; Yoo, J.; Yoshida, K.; Yuan, T.; Yu, M.; Zalewska, A.; Zalipska, J.; Zambelli, L.; Zaremba, K.; Ziembicki, M.; Zimmerman, E. D.; Zito, M.; Żmuda, J.; T2K Collaboration

    2015-06-01

    We report a measurement of the νμ charged current quasielastic cross-sections on carbon in the T2K on-axis neutrino beam. The measured charged current quasielastic cross-sections on carbon at mean neutrino energies of 1.94 GeV and 0.93 GeV are (11.95 ±0.19 (stat)-1.47+1.82(syst))×1 0-39 cm2/neutron , and (10.64 ±0.37 (stat)-1.65+2.03(syst))×1 0-39 cm2/neutron , respectively. These results agree well with the predictions of neutrino interaction models. In addition, we investigated the effects of the nuclear model and the multi-nucleon interaction.

  20. Marine neurotoxins: state of the art, bottlenecks, and perspectives for mode of action based methods of detection in seafood.

    PubMed

    Nicolas, Jonathan; Hendriksen, Peter J M; Gerssen, Arjen; Bovee, Toine F H; Rietjens, Ivonne M C M

    2014-01-01

    Marine biotoxins can accumulate in fish and shellfish, representing a possible threat for consumers. Many marine biotoxins affect neuronal function essentially through their interaction with ion channels or receptors, leading to different symptoms including paralysis and even death. The detection of marine biotoxins in seafood products is therefore a priority. Official methods for control are often still using in vivo assays, such as the mouse bioassay. This test is considered unethical and the development of alternative assays is urgently required. Chemical analyses as well as in vitro assays have been developed to detect marine biotoxins in seafood. However, most of the current in vitro alternatives to animal testing present disadvantages: low throughput and lack of sensitivity resulting in a high number of false-negative results. Thus, there is an urgent need for the development of new in vitro tests that would allow the detection of marine biotoxins in seafood products at a low cost, with high throughput combined with high sensitivity, reproducibility, and predictivity. Mode of action based in vitro bioassays may provide tools that fulfil these requirements. This review covers the current state of the art of such mode of action based alternative assays to detect neurotoxic marine biotoxins in seafood. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. C:N:P Molar Ratios, Sources and 14C Dating of Surficial Sediments from the NW Slope of Cuba.

    PubMed

    de la Lanza Espino, Guadalupe; Soto, Luis A

    2015-01-01

    The surficial sediments recovered from 12 sites located near the channel axis of the Florida Straits and the lower slope off NW Cuba were analyzed for total organic carbon (TOC), nitrogen (TN), phosphorus (TP), elemental C:N:P ratios, C and N isotopic values, and 14C dating. The depth profiles of TOC, TN, and TP (0-18 cm) displayed a downcore trend and a significant variation. The TOC values were low (0.15 to 0.62%; 66 to 516 µmol g(-1)). Sites near the island's lower slope had lower TOC average concentrations (158-333 µmol g(-1)) than those closer to the channel axis (averaging 341-516 µmol g(-1); p <0.05). The TN concentrations near the lower slope attained 0.11% (80 µmol g(-1)), whereas, towards the channel axis, they decreased to 0.07% (55 µmol g(-1); p<0.05). The C:N ratios ranged from 1.9 to 10.2. The mean molar C:N ratio (5.4) indicated a marine hemipelagic deposition. The TP was lower at sites near the lower slope (38.4 to 50.0 µmol gv; 0.12% to 0.16%) than those near the channel axis (50.0 to 66 µmol g(-1); 0.15 to 0.21%). C:P fluctuated from 7.7 to 14.1 in the surficial sediment layer. The bulk organic δ13Corg and δ15N values confirmed pelagic organic sources, and the 14C dating revealed that the sediments were deposited during the Holocene (1000-5000 yr BP). We suggest that the hydrodynamic conditions in the Straits influence vertical and advective fluxes of particulate organic material trapped in the mixed-layer, which reduces the particulate matter flux to the seabed.

  2. Crustal magnetization and accretion at the Southwest Indian Ridge near the Atlantis II fracture zone, 0-25 Ma

    USGS Publications Warehouse

    Hosford, A.; Tivey, M.; Matsumoto, T.; Dick, H.; Schouten, Hans; Kinoshita, H.

    2003-01-01

    We analyze geophysical data that extend from 0 to 25-Myr-old seafloor on both flanks of the Southwest Indian Ridge (SWIR). Lineated marine magnetic anomalies are consistent and identifiable within the study area, even over seafloor lacking a basaltic upper crust. The full spreading rate of 14 km/Myr has remained nearly constant since at least 20 Ma, but crustal accretion has been highly asymmetric, with half rates of 8.5 and 5.5 km/Myr on the Antarctic and African flanks, respectively. This asymmetry may be unique to a ???400 km wide corridor between large-offset fracture zones of the SWIR. In contrast to the Mid-Atlantic Ridge, crustal magnetization amplitudes correlate directly with seafloor topography along the present-day rift valleys. This pattern appears to be primarily a function of along-axis variations in crustal thickness, rather than magnetic mineralogy. Off-axis, magnetization amplitudes at paleo-segment ends are more positive than at paleo-segment midpoints, suggesting the presence of an induced component of magnetization within the lower crust or serpentinized upper mantle. Alteration of the magnetic source layer at paleo-segment midpoints reduces magnetization amplitudes by 70-80% within 20 Myr of accretion. Magnetic and Ocean Drilling Program (ODP) Hole 735B data suggest that the lower crust cooled quickly enough to lock in a primary thermoremanent magnetization that is in phase with that of the overlying upper crust. Thus magnetic polarity boundaries within the intrusive lower crust may be steeper than envisioned in prior models of ocean crustal magnetization. As the crust ages, the lower crust becomes increasingly important in preserving marine magnetic stripes.

  3. Research on the unsteady hydrodynamic characteristics of vertical axis tidal turbine

    NASA Astrophysics Data System (ADS)

    Zhang, Xue-wei; Zhang, Liang; Wang, Feng; Zhao, Dong-ya; Pang, Cheng-yan

    2014-03-01

    The unsteady hydrodynamic characteristics of vertical axis tidal turbine are investigated by numerical simulation based on viscous CFD method. The starting mechanism of the turbine is revealed through analyzing the interaction of its motion and dynamics during starting process. The operating hydrodynamic characteristics of the turbine in wave-current condition are also explored by combining with the linear wave theory. According to possible magnification of the cyclic loads in the maximum power tracking control of vertical axis turbine, a novel torque control strategy is put forward, which can improve the structural characteristics significantly without effecting energy efficiency.

  4. Analysis of a novel autonomous marine hybrid power generation/energy storage system with a high-voltage direct current link

    NASA Astrophysics Data System (ADS)

    Wang, Li; Lee, Dong-Jing; Lee, Wei-Jen; Chen, Zhe

    This paper presents both time-domain and frequency-domain simulated results of a novel marine hybrid renewable-energy power generation/energy storage system (PG/ESS) feeding isolated loads through an high-voltage direct current (HVDC) link. The studied marine PG subsystems comprise both offshore wind turbines and Wells turbines to respectively capture wind energy and wave energy from marine wind and ocean wave. In addition to wind-turbine generators (WTGs) and wave-energy turbine generators (WETGs) employed in the studied system, diesel-engine generators (DEGs) and an aqua electrolyzer (AE) absorbing a part of generated energy from WTGs and WETGs to generate available hydrogen for fuel cells (FCs) are also included in the PG subsystems. The ES subsystems consist of a flywheel energy storage system (FESS) and a compressed air energy storage (CAES) system to balance the required energy in the hybrid PG/ESS. It can be concluded from the simulation results that the proposed hybrid marine PG/ESS feeding isolated loads can stably operate to achieve system power-frequency balance condition.

  5. Marine Algae as Source of Novel Antileishmanial Drugs: A Review.

    PubMed

    Tchokouaha Yamthe, Lauve Rachel; Appiah-Opong, Regina; Tsouh Fokou, Patrick Valere; Tsabang, Nole; Fekam Boyom, Fabrice; Nyarko, Alexander Kwadwo; Wilson, Michael David

    2017-10-29

    Leishmaniasis is a vector-borne neglected tropical disease caused by protozoan parasites of the Leishmania genus and transmitted by the female Phlebotomus and Lutzomyia sand flies. The currently prescribed therapies still rely on pentavalent antimonials, pentamidine, paromomycin, liposomal amphotericin B, and miltefosine. However, their low efficacy, long-course treatment regimen, high toxicity, adverse side effects, induction of parasite resistance and high cost require the need for better drugs given that antileishmanial vaccines may not be available in the near future. Although most drugs are still derived from terrestrial sources, the interest in marine organisms as a potential source of promising novel bioactive natural agents has increased in recent years. About 28,000 compounds of marine origin have been isolated with hundreds of new chemical entities. Recent trends in drug research from natural resources indicated the high interest of aquatic eukaryotic photosynthetic organisms, marine algae in the search for new chemical entities given their broad spectrum and high bioactivities including antileishmanial potential. This current review describes prepared extracts and compounds from marine macroalgae along with their antileishmanial activity and provides prospective insights for antileishmanial drug discovery.

  6. Marine Algae as Source of Novel Antileishmanial Drugs: A Review

    PubMed Central

    Tchokouaha Yamthe, Lauve Rachel; Appiah-Opong, Regina; Tsabang, Nole; Nyarko, Alexander Kwadwo

    2017-01-01

    Leishmaniasis is a vector-borne neglected tropical disease caused by protozoan parasites of the Leishmania genus and transmitted by the female Phlebotomus and Lutzomyia sand flies. The currently prescribed therapies still rely on pentavalent antimonials, pentamidine, paromomycin, liposomal amphotericin B, and miltefosine. However, their low efficacy, long-course treatment regimen, high toxicity, adverse side effects, induction of parasite resistance and high cost require the need for better drugs given that antileishmanial vaccines may not be available in the near future. Although most drugs are still derived from terrestrial sources, the interest in marine organisms as a potential source of promising novel bioactive natural agents has increased in recent years. About 28,000 compounds of marine origin have been isolated with hundreds of new chemical entities. Recent trends in drug research from natural resources indicated the high interest of aquatic eukaryotic photosynthetic organisms, marine algae in the search for new chemical entities given their broad spectrum and high bioactivities including antileishmanial potential. This current review describes prepared extracts and compounds from marine macroalgae along with their antileishmanial activity and provides prospective insights for antileishmanial drug discovery. PMID:29109372

  7. Exploring local adaptation and the ocean acidification seascape - studies in the California Current Large Marine Ecosystem

    NASA Astrophysics Data System (ADS)

    Hofmann, G. E.; Evans, T. G.; Kelly, M. W.; Padilla-Gamiño, J. L.; Blanchette, C. A.; Washburn, L.; Chan, F.; McManus, M. A.; Menge, B. A.; Gaylord, B.; Hill, T. M.; Sanford, E.; LaVigne, M.; Rose, J. M.; Kapsenberg, L.; Dutton, J. M.

    2013-07-01

    The California Current Large Marine Ecosystem (CCLME), a temperate marine region dominated by episodic upwelling, is predicted to experience rapid environmental change in the future due to ocean acidification. Aragonite saturation state within the California Current System is predicted to decrease in the future, with near-permanent undersaturation conditions expected by the year 2050. Thus, the CCLME is a critical region to study due to the rapid rate of environmental change that resident organisms will experience and because of the economic and societal value of this coastal region. Recent efforts by a research consortium - the Ocean Margin Ecosystems Group for Acidification Studies (OMEGAS) - has begun to characterize a portion of the CCLME; both describing the mosaic of pH in coastal waters and examining the responses of key calcification-dependent benthic marine organisms to natural variation in pH and to changes in carbonate chemistry that are expected in the coming decades. In this review, we present the OMEGAS strategy of co-locating sensors and oceanographic observations with biological studies on benthic marine invertebrates, specifically measurements of functional traits such as calcification-related processes and genetic variation in populations that are locally adapted to conditions in a particular region of the coast. Highlighted in this contribution are (1) the OMEGAS sensor network that spans the west coast of the US from central Oregon to southern California, (2) initial findings of the carbonate chemistry amongst the OMEGAS study sites, (3) an overview of the biological data that describes the acclimatization and the adaptation capacity of key benthic marine invertebrates within the CCLME.

  8. The impact of debris on marine life.

    PubMed

    Gall, S C; Thompson, R C

    2015-03-15

    Marine debris is listed among the major perceived threats to biodiversity, and is cause for particular concern due to its abundance, durability and persistence in the marine environment. An extensive literature search reviewed the current state of knowledge on the effects of marine debris on marine organisms. 340 original publications reported encounters between organisms and marine debris and 693 species. Plastic debris accounted for 92% of encounters between debris and individuals. Numerous direct and indirect consequences were recorded, with the potential for sublethal effects of ingestion an area of considerable uncertainty and concern. Comparison to the IUCN Red List highlighted that at least 17% of species affected by entanglement and ingestion were listed as threatened or near threatened. Hence where marine debris combines with other anthropogenic stressors it may affect populations, trophic interactions and assemblages. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Marine defaunation: animal loss in the global ocean.

    PubMed

    McCauley, Douglas J; Pinsky, Malin L; Palumbi, Stephen R; Estes, James A; Joyce, Francis H; Warner, Robert R

    2015-01-16

    Marine defaunation, or human-caused animal loss in the oceans, emerged forcefully only hundreds of years ago, whereas terrestrial defaunation has been occurring far longer. Though humans have caused few global marine extinctions, we have profoundly affected marine wildlife, altering the functioning and provisioning of services in every ocean. Current ocean trends, coupled with terrestrial defaunation lessons, suggest that marine defaunation rates will rapidly intensify as human use of the oceans industrializes. Though protected areas are a powerful tool to harness ocean productivity, especially when designed with future climate in mind, additional management strategies will be required. Overall, habitat degradation is likely to intensify as a major driver of marine wildlife loss. Proactive intervention can avert a marine defaunation disaster of the magnitude observed on land. Copyright © 2015, American Association for the Advancement of Science.

  10. Flame retardants (PBDEs) in marine turtles, dugongs and seafood from Queensland, Australia.

    PubMed

    Hermanussen, S; Matthews, V; Päpke, O; Limpus, C J; Gaus, C

    2008-01-01

    Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in numerous products. These compounds have been found to enter the marine environment where they have the potential to bioaccumulate in biota. Limited information is currently available concerning the levels of PBDEs in Australian marine wildlife. This study presents baseline information on PBDE levels in a variety of marine species from Queensland, Australia and considers the influence of species-specific factors on contaminant levels and tissue distribution in marine turtles. Overall, the PBDE levels measured in this study are relatively low compared to marine biota from the northern hemisphere, indicating low level input into the marine system of Queensland. This is in general agreement with global estimates which suggest low PBDE usage in Australia. Previous studies, however, have found relatively high PBDE levels in Australian human milk and sera. This discrepancy in contamination trends between terrestrial and marine biota suggests that future transport of PBDEs may occur to the marine system in Australia.

  11. Management of the marine environment: integrating ecosystem services and societal benefits with the DPSIR framework in a systems approach.

    PubMed

    Atkins, Jonathan P; Burdon, Daryl; Elliott, Mike; Gregory, Amanda J

    2011-02-01

    Ever increasing and diverse use of the marine environment is leading to human-induced changes in marine life, habitats and landscapes, making necessary the development of marine policy that considers all members of the user community and addresses current, multiple, interacting uses. Taking a systems approach incorporating an understanding of The Ecosystem Approach, we integrate the DPSIR framework with ecosystem services and societal benefits, and the focus this gives allows us to create a specific framework for supporting decision making in the marine environment. Based on a linking of these three concepts, we present a set of basic postulates for the management of the marine environment and emphasise that these postulates should hold for marine management to be achieved. We illustrate these concepts using two case studies: the management of marine aggregates extraction in UK waters and the management of marine biodiversity at Flamborough Head, UK. Copyright © 2010 Elsevier Ltd. All rights reserved.

  12. Marine Tactical Command and Control System (MTACCS) Field Development System-1 (FDS-1) assessment: Final report

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

    Avery, L.W.; Hunt, S.T.; Savage, S.F.

    1992-04-01

    The United State Marine Corps (USMC) is continuing the development and fielding of the Marine Corps Tactical Command and Control System (MTACCS), a system which exists in varying states of development, fielding, or modernization. MTACCS is currently composed of the following components: Tactical Combat Operations System (TCO) for ground command and control (C2), Intelligence Analysis System (IAS) with a Genser terminal connected to a TCO workstation for intelligence C2, Marine Integrated Personnel System (MIPS) and a TCO workstation using the Marine Combat Personnel System (MCPERS) software for personnel C2, Marine Integrated Logistics System (MILOGS) which is composed of the Landingmore » Force Asset Distribution System (LFADS), the Marine Air-Ground Task Force (MAGTF) II, and a TCO terminal using the Marine Combat Logistics System (MCLOG) for logistics C2, Marine Corps Fire Support System (MCFSS) for fire support C2, and Advanced Tactical Air Command Central (ATACC) and the Improved Direct Air Support Central for aviation C2.« less

  13. Variable energy constant current accelerator structure

    DOEpatents

    Anderson, Oscar A.

    1990-01-01

    A variable energy, constant current ion beam accelerator structure is disclosed comprising an ion source capable of providing the desired ions, a pre-accelerator for establishing an initial energy level, a matching/pumping module having means for focusing means for maintaining the beam current, and at least one main accelerator module for continuing beam focus, with means capable of variably imparting acceleration to the beam so that a constant beam output current is maintained independent of the variable output energy. In a preferred embodiment, quadrupole electrodes are provided in both the matching/pumping module and the one or more accelerator modules, and are formed using four opposing cylinder electrodes which extend parallel to the beam axis and are spaced around the beam at 90.degree. intervals with opposing electrodes maintained at the same potential. Adjacent cylinder electrodes of the quadrupole structure are maintained at different potentials to thereby reshape the cross section of the charged particle beam to an ellipse in cross section at the mid point along each quadrupole electrode unit in the accelerator modules. The beam is maintained in focus by alternating the major axis of the ellipse along the x and y axis respectively at adjacent quadrupoles. In another embodiment, electrostatic ring electrodes may be utilized instead of the quadrupole electrodes.

  14. Application of very high harmonic fast waves for off-axis current drive in the DIII-D and FNSF-AT tokamaks

    DOE PAGES

    Prater, Ronald; Moeller, Charles P.; Pinsker, Robert I.; ...

    2014-06-26

    Fast waves at frequencies far above the ion cyclotron frequency and approaching the lower hybrid frequency (also called “helicons” or “whistlers”) have application to off-axis current drive in tokamaks with high electron beta. The high frequency causes the whistler-like behavior of the wave power nearly following field lines, but with a small radial component, so the waves spiral slowly toward the plasma center. The high frequency also contributes to strong damping. Modeling predicts robust off-axis current drive with good efficiency compared to alternatives in high performance discharges in DIII-D and Fusion Nuclear Science Facility (FNSF) when the electron beta ismore » above about 1.8%. Detailed analysis of ray behavior shows that ray trajectories and damping are deterministic (that is, not strongly affected by plasma profiles or initial ray conditions), unlike the chaotic ray behavior in lower frequency fast wave experiments. Current drive was found to not be sensitive to the launched value of the parallel index of refraction n||, so wave accessibility issues can be reduced. Finally, use of a traveling wave antenna provides a very narrow n|| spectrum, which also helps avoid accessibility problems.« less

  15. Marine Debris: An Opportunity for Marine Education.

    ERIC Educational Resources Information Center

    Heneman, Burr

    1989-01-01

    Provides awareness information on the sources, types, and serious effects on wildlife of nondegradable materials which are causing local as well as global problems. Discusses current ways the problem is being attacked and educational implications for environmental programs. (RT)

  16. Association between Mastication, the Hippocampus, and the HPA Axis: A Comprehensive Review.

    PubMed

    Azuma, Kagaku; Zhou, Qian; Niwa, Masami; Kubo, Kin-Ya

    2017-08-03

    Mastication is mainly involved in food intake and nutrient digestion with the aid of teeth. Mastication is also important for preserving and promoting general health, including hippocampus-dependent cognition. Both animal and human studies indicate that mastication influences hippocampal functions through the end product of the hypothalamic-pituitary-adrenal (HPA) axis, glucocorticoid (GC). Epidemiologic studies suggest that masticatory dysfunction in aged individuals, such as that resulting from tooth loss and periodontitis, acting as a source of chronic stress, activates the HPA axis, leading to increases in circulating GCs and eventually inducing various physical and psychological diseases, such as cognitive impairment, cardiovascular disorders, and osteoporosis. Recent studies demonstrated that masticatory stimulation or chewing during stressful conditions suppresses the hyperactivity of the HPA axis via GCs and GC receptors within the hippocampus, and ameliorates chronic stress-induced hippocampus-dependent cognitive deficits. Here, we provide a comprehensive overview of current research regarding the association between mastication, the hippocampus, and HPA axis activity. We also discuss several potential molecular mechanisms involved in the interactions between mastication, hippocampal function, and HPA axis activity.

  17. Association between Mastication, the Hippocampus, and the HPA Axis: A Comprehensive Review

    PubMed Central

    Azuma, Kagaku; Zhou, Qian; Niwa, Masami; Kubo, Kin-ya

    2017-01-01

    Mastication is mainly involved in food intake and nutrient digestion with the aid of teeth. Mastication is also important for preserving and promoting general health, including hippocampus-dependent cognition. Both animal and human studies indicate that mastication influences hippocampal functions through the end product of the hypothalamic-pituitary-adrenal (HPA) axis, glucocorticoid (GC). Epidemiologic studies suggest that masticatory dysfunction in aged individuals, such as that resulting from tooth loss and periodontitis, acting as a source of chronic stress, activates the HPA axis, leading to increases in circulating GCs and eventually inducing various physical and psychological diseases, such as cognitive impairment, cardiovascular disorders, and osteoporosis. Recent studies demonstrated that masticatory stimulation or chewing during stressful conditions suppresses the hyperactivity of the HPA axis via GCs and GC receptors within the hippocampus, and ameliorates chronic stress-induced hippocampus-dependent cognitive deficits. Here, we provide a comprehensive overview of current research regarding the association between mastication, the hippocampus, and HPA axis activity. We also discuss several potential molecular mechanisms involved in the interactions between mastication, hippocampal function, and HPA axis activity. PMID:28771175

  18. The Marine Corps’ Warrior Ethos: Practicality for Today’s Operating Environment

    DTIC Science & Technology

    2013-03-01

    warrior ethos if that ethos does not place value on all human life, adhere to core values and recognize the importance of leaders, at all levels ...Adherence to the warrior ethos is critical because in the current environment, small unit tactical actions have strategic level impacts. The current...entry- level training. Violations of the Marine Corps warrior ethos have occurred in recent conflicts. Exploration of these violations is vital to

  19. Predicting Trophic Interactions and Habitat Utilization in the California Current Ecosystem

    DTIC Science & Technology

    2013-09-30

    in the California Current Ecosystem Jerome Fiechter UC Santa Cruz Institute of Marine Sciences 1156 High Street Santa Cruz, CA 95064 phone... Ecosystem (CCLME), the long-term goal of our modeling approach is to better understand and characterize biological “hotspots” (i.e., the aggregation of...multiple marine organisms over multiple trophic levels) off the U.S. west coast and in other regions where similar fully-coupled ecosystem models may

  20. Observations of Near-Surface Current Shear Help Describe Oceanic Oil and Plastic Transport

    NASA Astrophysics Data System (ADS)

    Laxague, Nathan J. M.; Ö-zgökmen, Tamay M.; Haus, Brian K.; Novelli, Guillaume; Shcherbina, Andrey; Sutherland, Peter; Guigand, Cédric M.; Lund, Björn; Mehta, Sanchit; Alday, Matias; Molemaker, Jeroen

    2018-01-01

    Plastics and spilled oil pose a critical threat to marine life and human health. As a result of wind forcing and wave motions, theoretical and laboratory studies predict very strong velocity variation with depth over the upper few centimeters of the water column, an observational blind spot in the real ocean. Here we present the first-ever ocean measurements of the current vector profile defined to within 1 cm of the free surface. In our illustrative example, the current magnitude averaged over the upper 1 cm of the ocean is shown to be nearly four times the average over the upper 10 m, even for mild forcing. Our findings indicate that this shear will rapidly separate pieces of marine debris which vary in size or buoyancy, making consideration of these dynamics essential to an improved understanding of the pathways along which marine plastics and oil are transported.

  1. HST Observations Reveal the Curious Geometry of Circumgalactic Gas

    NASA Astrophysics Data System (ADS)

    Kacprzak, Glenn G.; Muzahid, Sowgat; Churchill, Christopher W.; Nielsen, Nikole M.; Charlton, Jane C.

    2016-06-01

    We have discovered that warm gas flows along galaxy major and minor axes detected out to 200 kpc. Our results are derived from a sample of HST-imaged isolated galaxies with nearby background quasars used to probe their 105K CGM detected in HST/COS UV spectra (traced by OVI absorption). We constrain the geometry of the gas to reside between 20-40 degrees of the projected major axis and within 60 degrees of the projected minor axis, with little-to-no gas found in between. Furthermore, strong absorption systems tend to be found along the minor axes of star-forming galaxies. All of our results are consistent with the current view of the CGM originating from major axis-fed inflows/recycled gas and from minor axis-driven outflows.

  2. HST Observations Reveal the Curious Geometry of Circumgalactic Gas

    NASA Astrophysics Data System (ADS)

    Kacprzak, Glenn G.; Muzahid, Sowgat; Churchill, Christopher W.; Nielsen, Nikole M.; Charlton, Jane C.

    2017-03-01

    We have discovered that warm gas flows along galaxy major and minor axes detected out to 200 kpc. Our results are derived from a sample of HST-imaged isolated galaxies with nearby background quasars used to probe their 105K CGM detected in HST/COS UV spectra (traced by Ovi absorption). We constrain the geometry of the gas to reside between 20-40 degrees of the projected major axis and within 60 degrees of the projected minor axis, with little-to-no gas found in between. Furthermore, strong absorption systems tend to be found along the minor axes of star-forming galaxies. All of our results are consistent with the current view of the CGM originating from major axis-fed inflows/recycled gas and from minor axis-driven outflows.

  3. Supercritical bedforms and sedimentary structures from field and core studies, Middle Eocene deep-marine base-of-slope environment, Ainsa Basin, Spanish Pyrenees

    NASA Astrophysics Data System (ADS)

    Cornard, Pauline; Pickering, Kevin

    2017-04-01

    In recent years, many researchers have focussed on supercritical- and subcritical-flow deposits using flume-tank experiments (e.g., Cartigny el al., 2011; Postma et al., 2014; Postma and Cartigny, 2014), or from direct observations on presently active deep-water systems (e.g., Hughes et al., 2012). Using outcrop and core examples from a base-of-slope environment in the Middle Eocene Ainsa Basin, Spanish Pyrenees, and with published experimental work, a range of deposits are interpreted as upper-flow regime sedimentary structures. This contribution focusses on the interpretation of several supercritical bedforms (antidunes and chutes-and-pools) observed on the field and upper-flow regime sedimentary structures recognized in cores. The spatial distribution of supercritical-flow deposits obtained from an analysis of field outcrops and core sedimentary logs are evaluated in relation to the depositional environment (channel axis, off-axis, margin and interfan). The frequency distributions of the bed thicknesses are also analysed in relation to supercritical versus subcritical bed-thickness distributions.

  4. Sequencing rare marine actinomycete genomes reveals high density of unique natural product biosynthetic gene clusters.

    PubMed

    Schorn, Michelle A; Alanjary, Mohammad M; Aguinaldo, Kristen; Korobeynikov, Anton; Podell, Sheila; Patin, Nastassia; Lincecum, Tommie; Jensen, Paul R; Ziemert, Nadine; Moore, Bradley S

    2016-12-01

    Traditional natural product discovery methods have nearly exhausted the accessible diversity of microbial chemicals, making new sources and techniques paramount in the search for new molecules. Marine actinomycete bacteria have recently come into the spotlight as fruitful producers of structurally diverse secondary metabolites, and remain relatively untapped. In this study, we sequenced 21 marine-derived actinomycete strains, rarely studied for their secondary metabolite potential and under-represented in current genomic databases. We found that genome size and phylogeny were good predictors of biosynthetic gene cluster diversity, with larger genomes rivalling the well-known marine producers in the Streptomyces and Salinispora genera. Genomes in the Micrococcineae suborder, however, had consistently the lowest number of biosynthetic gene clusters. By networking individual gene clusters into gene cluster families, we were able to computationally estimate the degree of novelty each genus contributed to the current sequence databases. Based on the similarity measures between all actinobacteria in the Joint Genome Institute's Atlas of Biosynthetic gene Clusters database, rare marine genera show a high degree of novelty and diversity, with Corynebacterium, Gordonia, Nocardiopsis, Saccharomonospora and Pseudonocardia genera representing the highest gene cluster diversity. This research validates that rare marine actinomycetes are important candidates for exploration, as they are relatively unstudied, and their relatives are historically rich in secondary metabolites.

  5. Sequencing rare marine actinomycete genomes reveals high density of unique natural product biosynthetic gene clusters

    PubMed Central

    Schorn, Michelle A.; Alanjary, Mohammad M.; Aguinaldo, Kristen; Korobeynikov, Anton; Podell, Sheila; Patin, Nastassia; Lincecum, Tommie; Jensen, Paul R.; Ziemert, Nadine

    2016-01-01

    Traditional natural product discovery methods have nearly exhausted the accessible diversity of microbial chemicals, making new sources and techniques paramount in the search for new molecules. Marine actinomycete bacteria have recently come into the spotlight as fruitful producers of structurally diverse secondary metabolites, and remain relatively untapped. In this study, we sequenced 21 marine-derived actinomycete strains, rarely studied for their secondary metabolite potential and under-represented in current genomic databases. We found that genome size and phylogeny were good predictors of biosynthetic gene cluster diversity, with larger genomes rivalling the well-known marine producers in the Streptomyces and Salinispora genera. Genomes in the Micrococcineae suborder, however, had consistently the lowest number of biosynthetic gene clusters. By networking individual gene clusters into gene cluster families, we were able to computationally estimate the degree of novelty each genus contributed to the current sequence databases. Based on the similarity measures between all actinobacteria in the Joint Genome Institute's Atlas of Biosynthetic gene Clusters database, rare marine genera show a high degree of novelty and diversity, with Corynebacterium, Gordonia, Nocardiopsis, Saccharomonospora and Pseudonocardia genera representing the highest gene cluster diversity. This research validates that rare marine actinomycetes are important candidates for exploration, as they are relatively unstudied, and their relatives are historically rich in secondary metabolites. PMID:27902408

  6. Underwater noise reduction of marine pile driving using a double pile.

    DOT National Transportation Integrated Search

    2015-12-01

    Impact pile driving of steel piles in marine environments produces extremely high sound levels in the water. : It has been shown that current pile driving noise attenuation techniques, such as bubble curtains and : cofferdams, provide limited noise r...

  7. The Physics of Marine Biology.

    ERIC Educational Resources Information Center

    Conn, Kathleen

    1992-01-01

    Discusses ways in which marine biology can be integrated into the physics classroom. Topics suggested for incorporation include the harmonic motion of ocean waves, ocean currents, the interaction of visible light with ocean water, pressure, light absorption, and sound transfer in water. (MDH)

  8. 76 FR 59657 - Submission for OMB Review; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-27

    ...: National Oceanic and Atmospheric Administration (NOAA). Title: Marine Recreational Information Program. OMB... a revision of a current information collection. Marine recreational anglers are surveyed for catch and effort data, fish biology data, and angler socioeconomic characteristics. These data are required...

  9. Regularized Biot-Savart Laws for Modeling Magnetic Configurations with Flux Ropes

    NASA Astrophysics Data System (ADS)

    Titov, V. S.; Downs, C.; Mikic, Z.; Torok, T.; Linker, J.

    2017-12-01

    Many existing models assume that magnetic flux ropes play a key role in solar flares and coronal mass ejections (CMEs). It is therefore important to develop efficient methods for constructing flux-rope configurations constrained by observed magnetic data and the initial morphology of CMEs. For this purpose, we have derived and implemented a compact analytical form that represents the magnetic field of a thin flux rope with an axis of arbitrary shape and a circular cross-section. This form implies that the flux rope carries axial current I and axial flux F, so that the respective magnetic field is the curl of the sum of toroidal and poloidal vector potentials proportional to I and F, respectively. We expressed the vector potentials in terms of modified Biot-Savart laws whose kernels are regularized at the axis in such a way that these laws define a cylindrical force-free flux rope with a parabolic profile of the axial current density, when the axis is straight. For the cases we have studied so far, we determined the shape of the rope axis by following the polarity inversion line of the eruptions' source region, using observed magnetograms. The height variation along the axis and other flux-rope parameters are estimated by means of potential field extrapolations. Using this heuristic approach, we were able to construct pre-eruption configurations for the 2009 February13 and 2011 October 1 CME events. These applications demonstrate the flexibility and efficiency of our new method for energizing pre-eruptive configurations in MHD simulations of CMEs. We discuss possible ways of optimizing the axis paths and other extensions of the method in order to make it more useful and robust. Research supported by NSF, NASA's HSR and LWS Programs, and AFOSR.

  10. Hyper- and hypocortisolism in bipolar disorder - A beneficial influence of lithium on the HPA-axis?

    PubMed

    Maripuu, Martin; Wikgren, Mikael; Karling, Pontus; Adolfsson, Rolf; Norrback, Karl-Fredrik

    2017-04-15

    A hyperactive hypothalamic-pituitary-adrenal axis (HPA-axis) is a well-known phenomenon in bipolar disorder (BD). However, hypocortisolism has also been described and found associated with depression, low quality of life and cardiovascular risk factors in BD patients. Although the pathophysiology related to hypocortisolism in BD is largely unknown, hypocortisolism is associated with chronic stress exposure and after inducing an initial rise in cortisol long-term stress may result in a transition to hypocortisolism. BD patients are throughout life often exposed to chronic stress. We therefore hypothesized that higher age would be associated with lower HPA-axis activity especially among patients without previous mood stabilizing treatment. This cross-sectional study consisted of 159 bipolar outpatients and 258 controls. A low-dose-dexamethasone-suppression-test (DST) was used to measure HPA-axis activity. Patients with BD showed a negative association between post DST cortisol and age (-3.0 nmol/l per year; p=0.007). This association gradually increased in subgroups that were naïve to lithium (-7.7 nmol/l per year; p=0.001) and "all mood stabilizers" (-11.4 nmol/l per year; p=0.004). Patients exhibiting hypercortisolism were characterized by younger age and female gender, whereas patients exhibiting hypocortisolism were characterized by long disease duration without prophylactic lithium treatment as well as absence of current lithium medication. Cross sectional study design. There was a negative association between HPA-axis activity and age in BD, rendering BD patients at risk for developing hypocortisolism. This association was most pronounced among patients without previous or current lithium prophylaxis. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. DARHT Axis-I Diode Simulations II: Geometrical Scaling

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

    Ekdahl, Carl A. Jr.

    2012-06-14

    Flash radiography of large hydrodynamic experiments driven by high explosives is a venerable diagnostic technique in use at many laboratories. Many of the largest hydrodynamic experiments study mockups of nuclear weapons, and are often called hydrotests for short. The dual-axis radiography for hydrodynamic testing (DARHT) facility uses two electron linear-induction accelerators (LIA) to produce the radiographic source spots for perpendicular views of a hydrotest. The first of these LIAs produces a single pulse, with a fixed {approx}60-ns pulsewidth. The second axis LIA produces as many as four pulses within 1.6-{micro}s, with variable pulsewidths and separation. There are a wide varietymore » of hydrotest geometries, each with a unique radiographic requirement, so there is a need to adjust the radiographic dose for the best images. This can be accomplished on the second axis by simply adjusting the pulsewidths, but is more problematic on the first axis. Changing the beam energy or introducing radiation attenuation also changes the spectrum, which is undesirable. Moreover, using radiation attenuation introduces significant blur, increasing the effective spot size. The dose can also be adjusted by changing the beam kinetic energy. This is a very sensitive method, because the dose scales as the {approx}2.8 power of the energy, but it would require retuning the accelerator. This leaves manipulating the beam current as the best means for adjusting the dose, and one way to do this is to change the size of the cathode. This method has been proposed, and is being tested. This article describes simulations undertaken to develop scaling laws for use as design tools in changing the Axis-1 beam current by changing the cathode size.« less

  12. The role of BDNF and HPA axis in the neurobiology of burnout syndrome.

    PubMed

    Onen Sertoz, Ozen; Tolga Binbay, Ibrahim; Koylu, Ersin; Noyan, Aysin; Yildirim, Emre; Elbi Mete, Hayriye

    2008-08-01

    Chronic stress is known to affect the HPA axis. The few clinical studies which have been conducted on HPA-axis function in burnout have produced inconsistent results. The etiological relationship between sBDNF and burnout has not yet been studied. The aim of the current study was to investigate the role of BDNF and HPA axis in the neurobiology of burnout. In the current study 37 clinically diagnosed burnout participants were compared with 35 healthy controls in terms of BDNF, HPA axis, burnout symptoms, depression, anxiety and psychosomatic complaints. Basal serum cortisol, sBDNF and cortisol level after 1 mg DST was sampled. We found no significant differences in terms of HPA-axis function (for basal serum cortisol, p=0.592; for cortisol level after 1 mg DST, p=0.921), but we did find lowered sBDNF levels in burnout group (88.66+/-18.15 pg/ml) as compared to healthy controls (102.18+/-20.92 pg/ml) and the difference was statistically significant (p=0.005). Logistic Regression Analysis revealed that emotional exhaustion (p=0.05), depersonalization (p=0.005) and depression (p=0.025) were significantly associated with burnout. sBDNF levels correlated negatively with emotional exhaustion (r=-,268, p=0.026), depersonalization (r=-,333, p=0.005) and correlated positively with competence (r=0.293, p=0.015) sub-scales of burnout inventory. However, there were no significant relationships between cortisol levels and sBDNF levels (r=0.80, p=0.51), depression, anxiety, psychosomatic complaints and burnout inventory. Our results suggest that low BDNF might contribute to the neurobiology of burnout syndrome and it seems to be associated with burnout symptoms including altered mood and cognitive functions.

  13. Cumulative human impacts on marine predators.

    PubMed

    Maxwell, Sara M; Hazen, Elliott L; Bograd, Steven J; Halpern, Benjamin S; Breed, Greg A; Nickel, Barry; Teutschel, Nicole M; Crowder, Larry B; Benson, Scott; Dutton, Peter H; Bailey, Helen; Kappes, Michelle A; Kuhn, Carey E; Weise, Michael J; Mate, Bruce; Shaffer, Scott A; Hassrick, Jason L; Henry, Robert W; Irvine, Ladd; McDonald, Birgitte I; Robinson, Patrick W; Block, Barbara A; Costa, Daniel P

    2013-01-01

    Stressors associated with human activities interact in complex ways to affect marine ecosystems, yet we lack spatially explicit assessments of cumulative impacts on ecologically and economically key components such as marine predators. Here we develop a metric of cumulative utilization and impact (CUI) on marine predators by combining electronic tracking data of eight protected predator species (n=685 individuals) in the California Current Ecosystem with data on 24 anthropogenic stressors. We show significant variation in CUI with some of the highest impacts within US National Marine Sanctuaries. High variation in underlying species and cumulative impact distributions means that neither alone is sufficient for effective spatial management. Instead, comprehensive management approaches accounting for both cumulative human impacts and trade-offs among multiple stressors must be applied in planning the use of marine resources.

  14. Chapter D: With or Without Salt-a Comparison of Marine and Continental-Lacustrine Diatomite Deposits

    USGS Publications Warehouse

    Moyle, Phillip R.; Dolley, Thomas P.

    2003-01-01

    Diatoms in sedimentary deposits of marine and continental, especially lacustrine, origin have similar nutrient (for example, phosphate, nitrate, and silica) and light requirements; however, their geologic ranges and physiographic environments vary. Marine diatoms range in age from Early Cretaceous to Holocene, and continental diatoms range in age from Eocene to Holocene; however, most commercial diatomites, both marine and lacustrine, were deposited during the Miocene. Marine deposits of commercial value generally accumulated along continental margins with submerged coastal basins and shelves where wind-driven boundary currents provided the nutrient-rich upwelling conditions capable of supporting a productive diatom habitat. Commercial freshwater diatomite deposits occur in volcanic terrains associated with events that formed sediment-starved drainage basins, such as the Basin and Range Province, particularly in Nevada. Marine habitats generally are characterized by stable conditions of temperature, salinity, pH, nutrients, and water currents, in contrast to lacustrine habitats, which are characterized by wide variations in these conditions. Marine deposits generally are of higher quality and contain larger resources, owing to their greater areal extent and thickness, whereas most of the world's known diatomites are of lacustrine origin. Both types of deposit are commonly mined by open-pit methods and subjected to processing designed to remove organic matter, CO2, pore water, and inorganic contaminants in order to produce purified products. The highest quality diatomites, predominantly from marine sources, are used in filtration, although both types of deposit produce filter grades, and additional end uses include fillers, additives, absorbents, and abrasives.

  15. Climate change influences on marine infectious diseases: implications for management and society

    USGS Publications Warehouse

    Burge, Colleen A.; Eakin, C. Mark; Friedman, Carolyn S.; Froelich, Brett; Hershberger, Paul K.; Hofmann, Eileen E.; Petes, Laura E.; Prager, Katherine C.; Weil, Ernesto; Willis, Bette L.; Ford, Susan E.; Harvell, C. Drew

    2014-01-01

    Infectious diseases are common in marine environments, but the effects of a changing climate on marine pathogens are not well understood. Here, we focus on reviewing current knowledge about how the climate drives hostpathogen interactions and infectious disease outbreaks. Climate-related impacts on marine diseases are being documented in corals, shellfish, finfish, and humans; these impacts are less clearly linked to other organisms. Oceans and people are inextricably linked, and marine diseases can both directly and indirectly affect human health, livelihoods, and well-being. We recommend an adaptive management approach to better increase the resilience of ocean systems vulnerable to marine diseases in a changing climate. Land-based management methods of quarantining, culling, and vaccinating are not successful in the ocean; therefore, forecasting conditions that lead to outbreaks and designing tools/approaches to influence these conditions may be the best way to manage marine disease.

  16. The high-efficiency laundry metering and marketing analysis (THELMA) project: Volume 2 -- Laboratory testing of clothes washers. Final report

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

    NONE

    1997-10-01

    Horizontal axis (H-axis) clothes washers use less water and energy than conventional top-loading vertical axis (V-axis) clothes washers, yet sales in the US are insignificant. In the High Efficiency Laundry Metering and Market Analysis (THELMA) project, EPRI and a group of utilities have pooled their resources to develop the basis for successful DSM programs to accelerate the acceptance of this technology in the US market. This report covers the laboratory test phase of the THELMA project. The objective of this effort was to measure the performance of a representative sample of currently manufactured H-axis washers and to compare this performancemore » to that of a typical V-axis washer. Several aspects of performance were measured, with the emphasis on measures of energy consumption and water consumption: DOE washer capacity; hot and cold water consumption; energy consumption by the washer mechanical drive; DOE energy factor; water extraction effectiveness; effect of water extraction effectiveness on dryer energy; soil removal effectiveness; rinsing effectiveness; and gentleness of action. Eight H-axis washers, provided by US or European manufacturers, were tested. Test results varied over a range for these eight machines, but on average, the H-axis washers used 40% less energy (normalized to basket volume) and 25% less water (normalized to basket volume) when measured according to the DOE test procedure.« less

  17. Laboratory testing of clothes washers. Final report

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

    Dieckmann, J.; Murphy, W.

    1995-12-01

    Horizontal axis (H-axis) clothes washers use less water and energy than conventional top-loading vertical axis (V-axis) clothes washers, yet sales in the US are insignificant. In the High Efficiency Laundry Metering and Market Analysis (THELMA) project, EPRI and a group of utilities have pooled their resources to develop the basis for successful DSM programs to accelerate the acceptance of this technology in the US market. This report covers the laboratory test phase of the THELMA project. The objective of this effort was to measure the performance of a representative sample of currently manufactured H-axis washers and to compare this performancemore » to that of a typical V-axis washer. Several aspects of performance were measured, with the emphasis on measures of energy consumption and water consumption: DOE washer capacity; Hot and cold water consumption; Energy consumption by the washer mechanical drive; DOE energy factor; Water extraction effectiveness; Effect of water extraction effectiveness on dryer energy; Soil removal effectiveness; Rinsing effectiveness and Gentleness of action. Six H-axis washers, provided by US or European manufacturers, were tested. Test results varied over a range for these six machines, but on average, the H-axis washers used 40% less energy (normalized to basket volume) and 25% less water (normalized to basket volume) when measured according to the DOE test procedure.« less

  18. Investigating the effect of acute sleep deprivation on hypothalamic-pituitary-adrenal-axis response to a psychosocial stressor.

    PubMed

    Vargas, Ivan; Lopez-Duran, Nestor

    2017-05-01

    The hypothalamic-pituitary-adrenal (HPA) axis has been previously identified as one potential mechanism that may explain the link between sleep deprivation and negative health outcomes. However, few studies have examined the direct association between sleep deprivation and HPA-axis functioning, particularly in the context of stress. Therefore, the aim of the current study was to investigate the relationship between acute sleep deprivation and HPA-axis reactivity to a psychosocial stressor. Participants included 40 healthy, young adults between the ages of 18-29. The current protocol included spending two nights in the laboratory. After an adaptation night (night 1), participants were randomized into either a sleep deprivation condition (29 consecutive hours awake) or a control condition (night 2). Following the second night, all participants completed the Trier Social Stress Test (TSST). Salivary cortisol was collected before, during, and after the TSST. Results indicated that there were significant group differences in cortisol stress reactivity. Specifically, compared to participants in the control condition, participants in the sleep deprivation condition had greater baseline (i.e., pre-stress) cortisol, yet a blunted cortisol response to the TSST. Taken together, a combination of elevated baseline cortisol (and its subsequent effect on HPA-axis regulatory processes) and a relative 'ceiling' on the amount of cortisol a laboratory stressor can produce may explain why participants in the sleep deprivation condition demonstrated blunted cortisol responses. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Multi-Axis Thrust Measurements of the EO-1 Pulsed Plasma Thruster

    NASA Technical Reports Server (NTRS)

    Arrington, Lynn A.; Haag, Thomas W.

    1999-01-01

    Pulsed plasma thrusters are low thrust propulsive devices which have a high specific impulse at low power. A pulsed plasma thruster is currently scheduled to fly as an experiment on NASA's Earth Observing-1 satellite mission. The pulsed plasma thruster will be used to replace one of the reaction wheels. As part of the qualification testing of the thruster it is necessary to determine the nominal thrust as a function of charge energy. These data will be used to determine control algorithms. Testing was first completed on a breadboard pulsed plasma thruster to determine nominal or primary axis thrust and associated propellant mass consumption as a function of energy and then later to determine if any significant off-axis thrust component existed. On conclusion that there was a significant off-axis thrust component with the bread-board in the direction of the anode electrode, the test matrix was expanded on the flight hardware to include thrust measurements along all three orthogonal axes. Similar off-axis components were found with the flight unit.

  20. The role of sex and autonomy-connectedness in internalizing and externalizing personality pathology, coping and axis-I pathology: among psychiatric and healthy elderly.

    PubMed

    Bachrach, Nathan; Croon, Marcel; Bekker, Marrie

    2017-06-01

    In the current study we investigated the relationship of sex and autonomy-connectedness with internalizing and externalizing personality disorder symptoms (PDS), coping and axis-I pathology in older age. A path model was tested which was based on neo-analytical object relation, attachment- and primary-personality theory, among 100 clinical and 106 non-clinical elderly. In line with our model, autonomy-connectedness (self-awareness and capacity of managing new situations) was strongly associated to internalizing PDS in both groups. In both groups, neither sex nor autonomy-connectedness predicted externalizing PDS. Sex, internalizing as well as externalizing PDS and reactive defensive coping were associated to axis-I psychopathology. We conclude that sex and autonomy-connectedness were, similarly as in adult populations, associated to internalizing PDS and axis-I pathology. Treatment of elderly with internalizing PDS and axis-I psychopathology should therefore focus on enhancing autonomy-connectedness.

  1. The vibration discomfort of standing people: evaluation of multi-axis vibration.

    PubMed

    Thuong, Olivier; Griffin, Michael J

    2015-01-01

    Few studies have investigated discomfort caused by multi-axis vibration and none has explored methods of predicting the discomfort of standing people from simultaneous fore-and-aft, lateral and vertical vibration of a floor. Using the method of magnitude estimation, 16 subjects estimated their discomfort caused by dual-axis and tri-axial motions (octave-bands centred on either 1 or 4 Hz with various magnitudes in the fore-and-aft, lateral and vertical directions) and the discomfort caused by single-axis motions. The method of predicting discomfort assumed in current standards (square-root of the sums of squares of the three components weighted according to their individual contributions to discomfort) provided reasonable predictions of the discomfort caused by multi-axis vibration. Improved predictions can be obtained for specific stimuli, but no single simple method will provide accurate predictions for all stimuli because the rate of growth of discomfort with increasing magnitude of vibration depends on the frequency and direction of vibration.

  2. The c-axis charge traveling wave in a coupled system of Josephson junctions

    NASA Astrophysics Data System (ADS)

    Shukrinov, Yu. M.; Hamdipour, M.

    2012-05-01

    We demonstrate a manifestation of the charge traveling wave along the c axis (TW) in current voltage characteristics of coupled Josephson junctions in high- T c superconductors. The branches related to the TW with different wavelengths are found for the stacks with different number of Josephson junctions at different values of system's parameters. Transitions between the TW branches and the outermost branch are observed. The electric charge in the superconducting layers and charge-charge correlation functions for TW and outermost branches show different behavior with bias current. We propose an experimental testing of the TW branching by microwave irradiation.

  3. A Review of Phage Therapy against Bacterial Pathogens of Aquatic and Terrestrial Organisms.

    PubMed

    Doss, Janis; Culbertson, Kayla; Hahn, Delilah; Camacho, Joanna; Barekzi, Nazir

    2017-03-18

    Since the discovery of bacteriophage in the early 1900s, there have been numerous attempts to exploit their innate ability to kill bacteria. The purpose of this report is to review current findings and new developments in phage therapy with an emphasis on bacterial diseases of marine organisms, humans, and plants. The body of evidence includes data from studies investigating bacteriophage in marine and land environments as modern antimicrobial agents against harmful bacteria. The goal of this paper is to present an overview of the topic of phage therapy, the use of phage-derived protein therapy, and the hosts that bacteriophage are currently being used against, with an emphasis on the uses of bacteriophage against marine, human, animal and plant pathogens.

  4. Electron dynamics in a plasma focus. [electron acceleration

    NASA Technical Reports Server (NTRS)

    Hohl, F.; Gary, S. P.; Winters, P. A.

    1977-01-01

    Results are presented of a numerical integration of the three-dimensional relativistic equations of motion of electrons subject to given electric and magnetic fields deduced from experiments. Fields due to two different models are investigated. For the first model, the fields are those due to a circular distribution of axial current filaments. As the current filaments collapse toward the axis, large azimuthal magnetic and axial electric fields are induced. These fields effectively heat the electrons to a temperature of approximately 8 keV and accelerate electrons within the radius of the filaments to high axial velocities. Similar results are obtained for the current-reduction phase of focus formation. For the second model, the fields are those due to a uniform current distribution. Both the current-reduction and the compression phases were studied. These is little heating or acceleration of electrons during the compression phase because the electrons are tied to the magnetic field. However, during the current-reduction phase, electrons near the axis are accelerated toward the center electrode and reach energies of 100 keV. A criterion is obtained which limits the runaway electron current to about 400 A.

  5. Spaceborne Sensors Track Marine Debris Circulation in the Gulf of Mexico

    NASA Technical Reports Server (NTRS)

    Reahard, Ross; Mitchell, Brandie; Lee, Lucas; Pezold, Blaise; Brook, Chris; Mallett, Candis; Barrett, Shelby; Albin, Aaron

    2011-01-01

    Marine debris is a problem for coastal areas throughout the world, including the Gulf of Mexico. To aid the NOAA Marine Debris Program in monitoring marine debris dispersal and regulating marine debris practices, sea surface height and height anomaly data provided by the Colorado Center for Astrodynamics Research at the University of Colorado, Boulder, were utilized to help assess trash and other discarded items that routinely wash ashore in southeastern Texas, at Padre Island National Seashore. These data were generated from the NASA radar altimeter satellites TOPEX/Poseidon, Jason 1, and Jason 2, as well as the European altimeter satellites ERS-1, ERS-2 (European Remote Sensing Satellite), and ENVISAT (Environmental Satellite). Sea surface temperature data from MODIS were used to study of the dynamics of the Loop Current. Sea surface height and MODIS data analysis were used to show that warm water in the core of eddies, which periodically separate from the Loop Current, can be as high as 30 cm above the surrounding water. These eddies are known to directly transfer marine debris to the western continental shelf and the elevated area of water can be tracked using satellite radar altimeter data. Additionally, using sea surface height, geostrophic velocity, and particle path data, foretracking and backtracking simulations were created. These simulation runs demonstrated that marine debris on Padre Island National Seashore may arise from a variety of sources, such as commercial fishing/shrimping, the oil and gas industry, recreational boaters, and from rivers that empty into the Gulf of Mexico.

  6. Exploring local adaptation and the ocean acidification seascape - studies in the California Current Large Marine Ecosystem

    NASA Astrophysics Data System (ADS)

    Hofmann, G. E.; Evans, T. G.; Kelly, M. W.; Padilla-Gamiño, J. L.; Blanchette, C. A.; Washburn, L.; Chan, F.; McManus, M. A.; Menge, B. A.; Gaylord, B.; Hill, T. M.; Sanford, E.; LaVigne, M.; Rose, J. M.; Kapsenberg, L.; Dutton, J. M.

    2014-02-01

    The California Current Large Marine Ecosystem (CCLME), a temperate marine region dominated by episodic upwelling, is predicted to experience rapid environmental change in the future due to ocean acidification. The aragonite saturation state within the California Current System is predicted to decrease in the future with near-permanent undersaturation conditions expected by the year 2050. Thus, the CCLME is a critical region to study due to the rapid rate of environmental change that resident organisms will experience and because of the economic and societal value of this coastal region. Recent efforts by a research consortium - the Ocean Margin Ecosystems Group for Acidification Studies (OMEGAS) - has begun to characterize a portion of the CCLME; both describing the spatial mosaic of pH in coastal waters and examining the responses of key calcification-dependent benthic marine organisms to natural variation in pH and to changes in carbonate chemistry that are expected in the coming decades. In this review, we present the OMEGAS strategy of co-locating sensors and oceanographic observations with biological studies on benthic marine invertebrates, specifically measurements of functional traits such as calcification-related processes and genetic variation in populations that are locally adapted to conditions in a particular region of the coast. Highlighted in this contribution are (1) the OMEGAS sensor network that spans the west coast of the US from central Oregon to southern California, (2) initial findings of the carbonate chemistry amongst the OMEGAS study sites, and (3) an overview of the biological data that describes the acclimatization and the adaptation capacity of key benthic marine invertebrates within the CCLME.

  7. Mariner Jupiter/Saturn infrared instrument study

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The Mariner Jupiter/Saturn infrared instrumentation conceptual design study was conducted to determine the physical and operational characteristics of the instruments needed to satisfy the experiment science requirements. The design of the instruments is based on using as many proven concepts as possible. Many design features are taken from current developments such as the Mariner, Pioneer 10, Viking Orbiter radiometers, and Nimbus D spectrometer. Calibration techniques and error analysis for the instrument system are discussed.

  8. Dominating Duffer’s Domain: Lessons for the U.S. Marine corps Information Operations Practitioner

    DTIC Science & Technology

    2017-01-01

    an IO working group session, the public affairs officer pointed out that we had more latitude for broadcasts that were not MISO influence products ...this Duffer’s Drift–inspired text does for information operations ( IO ) what the original did for defensive tactics: effectively communicate timeless...fiction are Marines with current or future IO responsibilities and at least some understanding of Marine Expeditionary Unit (MEU) staffing processes

  9. Vitamin D Axis in Inflammatory Bowel Diseases: Role, Current Uses and Future Perspectives

    PubMed Central

    Del Pinto, Rita; Ferri, Claudio; Cominelli, Fabio

    2017-01-01

    Increasing evidence supports the concept that the vitamin D axis possesses immunoregulatory functions, with vitamin D receptor (VDR) status representing the major determinant of vitamin D’s pleiotropic effects. Vitamin D promotes the production of anti-microbial peptides, including β-defensins and cathelicidins, the shift towards Th2 immune responses, and regulates autophagy and epithelial barrier integrity. Impairment of vitamin D-mediated pathways are associated with chronic inflammatory conditions, including inflammatory bowel diseases (IBD). Interestingly, inhibition of vitamin D pathways results in dysbiosis of the gut microbiome, which has mechanistically been implicated in the development of IBD. Herein, we explore the role of the vitamin D axis in immune-mediated diseases, with particular emphasis on its interplay with the gut microbiome in the pathogenesis of IBD. The potential clinical implications and therapeutic relevance of this interaction will also be discussed, including optimizing VDR function, both with vitamin D analogues and probiotics, which may represent a complementary approach to current IBD treatments. PMID:29112157

  10. Plastics in the Marine Environment

    NASA Astrophysics Data System (ADS)

    Law, Kara Lavender

    2017-01-01

    Plastics contamination in the marine environment was first reported nearly 50 years ago, less than two decades after the rise of commercial plastics production, when less than 50 million metric tons were produced per year. In 2014, global plastics production surpassed 300 million metric tons per year. Plastic debris has been detected worldwide in all major marine habitats, in sizes from microns to meters. In response, concerns about risks to marine wildlife upon exposure to the varied forms of plastic debris have increased, stimulating new research into the extent and consequences of plastics contamination in the marine environment. Here, I present a framework to evaluate the current understanding of the sources, distribution, fate, and impacts of marine plastics. Despite remaining knowledge gaps in mass budgeting and challenges in investigating ecological impacts, the increasing evidence of the ubiquity of plastics contamination in the marine environment, the continued rapid growth in plastics production, and the evidence—albeit limited—of demonstrated impacts to marine wildlife support immediate implementation of source-reducing measures to decrease the potential risks of plastics in the marine ecosystem.

  11. Marine Fish Proteins and Peptides for Cosmeceuticals: A Review

    PubMed Central

    Venkatesan, Jayachandran; Anil, Sukumaran; Kim, Se-Kwon; Shim, Min Suk

    2017-01-01

    Marine fish provide a rich source of bioactive compounds such as proteins and peptides. The bioactive proteins and peptides derived from marine fish have gained enormous interest in nutraceutical, pharmaceutical, and cosmeceutical industries due to their broad spectrum of bioactivities, including antioxidant, antimicrobial, and anti-aging activities. Recently, the development of cosmeceuticals using marine fish-derived proteins and peptides obtained from chemical or enzymatical hydrolysis of fish processing by-products has increased rapidly owing to their activities in antioxidation and tissue regeneration. Marine fish-derived collagen has been utilized for the development of cosmeceutical products due to its abilities in skin repair and tissue regeneration. Marine fish-derived peptides have also been utilized for various cosmeceutical applications due to their antioxidant, antimicrobial, and matrix metalloproteinase inhibitory activities. In addition, marine fish-derived proteins and hydrolysates demonstrated efficient anti-photoaging activity. The present review highlights and presents an overview of the current status of the isolation and applications of marine fish-derived proteins and peptides. This review also demonstrates that marine fish-derived proteins and peptides have high potential for biocompatible and effective cosmeceuticals. PMID:28524092

  12. Plastics in the Marine Environment.

    PubMed

    Law, Kara Lavender

    2017-01-03

    Plastics contamination in the marine environment was first reported nearly 50 years ago, less than two decades after the rise of commercial plastics production, when less than 50 million metric tons were produced per year. In 2014, global plastics production surpassed 300 million metric tons per year. Plastic debris has been detected worldwide in all major marine habitats, in sizes from microns to meters. In response, concerns about risks to marine wildlife upon exposure to the varied forms of plastic debris have increased, stimulating new research into the extent and consequences of plastics contamination in the marine environment. Here, I present a framework to evaluate the current understanding of the sources, distribution, fate, and impacts of marine plastics. Despite remaining knowledge gaps in mass budgeting and challenges in investigating ecological impacts, the increasing evidence of the ubiquity of plastics contamination in the marine environment, the continued rapid growth in plastics production, and the evidence-albeit limited-of demonstrated impacts to marine wildlife support immediate implementation of source-reducing measures to decrease the potential risks of plastics in the marine ecosystem.

  13. Design of a coil satellite centrifuge and its performance on counter-current chromatographic separation of 4-methylumbelliferyl sugar derivatives with polar organic-aqueous two-phase solvent systems.

    PubMed

    Shinomiya, Kazufusa; Tokura, Koji; Kimura, Emiru; Takai, Midori; Harikai, Naoki; Yoshida, Kazunori; Yanagidaira, Kazuhiro; Ito, Yoichiro

    2015-05-01

    A new high-speed counter-current chromatograph, named coil satellite centrifuge (CSC), was designed and fabricated in our laboratory. The CSC apparatus produces the satellite motion such that the coiled column simultaneously rotates around the sun axis (the angular velocity, ω1), the planet axis (ω2) and the satellite axis (the central axis of the column) (ω3). In order to achieve this triplicate rotary motion without twisting of the flow tube, the rotation of each axis was determined by the following formula: ω1=ω2+ω3. This relation enabled to lay out the flow tube without twisting by the simultaneous rotation of three axes. The flow tube was introduced from the bottom side of the apparatus into the sun axis of the first rotary frame reaching the upper side of the planet axis and connected to the column in the satellite axis. The performance of the apparatus was examined on separation of 4-methylumbelliferyl (MU) sugar derivatives as test samples with organic-aqueous two-phase solvent systems composed of ethyl acetate/1-butanol/water (3:2:5, v/v) for lower phase mobile and (1:4:5, v/v) for upper phase mobile. With lower phase mobile, five 4-MU sugar derivatives including β-D-cellobioside (Cel), β-D-glucopyranoside, α-D-mannopyranoside, β-D-fucopyranoside and α-L-fucopyranoside (α-L-Fuc) were separated with the combined rotation around each axis at counterclockwise (CCW) (ω1) - CCW (ω2) - CCW (ω3) by the flow tube distribution. With upper phase mobile, three 4-MU sugar derivatives including α-L-Fuc, β-D-galactopyranoside and Cel were separated with the combined rotation around each axis at clockwise (CW) (ω1) - CW (ω2) - CW (ω3) by the flow tube distribution. A series of experiments on peak resolution and stationary phase retention revealed that better partition efficiencies were obtained at the flow rate of 0.5 mL/min (column 1) and 0.8 mL/min (column 2) for lower phase mobile and 0.2 mL/min (column 1) and 0.4 mL/min (column 2) for upper phase mobile when using the left-handed multilayer coil (total capacity: 57.0 mL for column 1 and 75.0 mL for column 2) under the rotation speeds of approximately ω1=300 rpm, ω2=150 rpm and ω3=150 rpm. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Coastal Warning Display Program

    Science.gov Websites

    ! Boating Safety Beach Hazards Rip Currents Hypothermia Hurricanes Thunderstorms Lightning Coastal Flooding Tsunamis 406 EPIRB's National Weather Service Marine Forecasts COASTAL WARNING DISPLAY PROGRAM Marine COASTAL WARNING DISPLAY PROGRAM As of February 15, 1989, the National Weather Service retired its Coastal

  15. Suitability Analysis For Scuba Diving To Develop Marine Tourism At Saebus Island, East Java, Indonesia

    NASA Astrophysics Data System (ADS)

    Wijaya, Putranto; Putra, Tri; Hidayat, Fatra; Levraeni, Chandra; Rizmaadi, Mada; Ambariyanto, Ambariyanto

    2018-02-01

    Indonesian government currently has policies to improve the performance of the tourism sector, including marine tourism. One of the attractions of marine tourism is the coral ecosystem especially through scuba diving activities. The purpose of this study was to determine the suitability of the coral ecosystem on Saebus Island, East Java, to find appropriate locations for scuba diving activities. Purposive samplings were done around the island to determine four stations which will be assessed through suitability analysis. Tourism Suitability Index was used to assess all stations for scuba diving activities. The result showed that all four stations were categorized as very suitable with the score: 85%, 85%, 85% and 83%, respectively. Several aspects that need to be improved and anticipated for diving at all stations are coral coverage and water current. These results suggest that there are several spots around Saebus Island that are suitable for diving site, and can be promoted as marine tourism destination.

  16. Origin of marine debris is related to disposable packs of ultra-processed food.

    PubMed

    Andrades, Ryan; Martins, Agnaldo S; Fardim, Lorena M; Ferreira, Juliana S; Santos, Robson G

    2016-08-15

    Marine debris is currently distributed worldwide, and the discard and contamination pose hazards to human and wildlife health. One of the gaps in debris science is tracking the source of debris to better evaluate and avoid the pathway of debris from the source to marine environment. For this, we evaluated three beaches of different urbanization levels and environmental influences; a low urbanized beach, a highly urbanized beach and a non-urbanized estuary-associated beach, in order to determine the sources and original use of debris. Plastic was the major material found on beaches, and the urbanized beach recorded the highest debris densities. Marine debris was primarily from land-based sources, and the debris recorded in all beaches was mainly assigned as food-related items. Our results highlight the major presence of disposable and short-lived products comprising the majority of debris that enters the ocean and draw attention to the unsustainable lifestyle of current society. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Current Status and Future Prospects of Marine Natural Products (MNPs) as Antimicrobials.

    PubMed

    Choudhary, Alka; Naughton, Lynn M; Montánchez, Itxaso; Dobson, Alan D W; Rai, Dilip K

    2017-08-28

    The marine environment is a rich source of chemically diverse, biologically active natural products, and serves as an invaluable resource in the ongoing search for novel antimicrobial compounds. Recent advances in extraction and isolation techniques, and in state-of-the-art technologies involved in organic synthesis and chemical structure elucidation, have accelerated the numbers of antimicrobial molecules originating from the ocean moving into clinical trials. The chemical diversity associated with these marine-derived molecules is immense, varying from simple linear peptides and fatty acids to complex alkaloids, terpenes and polyketides, etc. Such an array of structurally distinct molecules performs functionally diverse biological activities against many pathogenic bacteria and fungi, making marine-derived natural products valuable commodities, particularly in the current age of antimicrobial resistance. In this review, we have highlighted several marine-derived natural products (and their synthetic derivatives), which have gained recognition as effective antimicrobial agents over the past five years (2012-2017). These natural products have been categorized based on their chemical structures and the structure-activity mediated relationships of some of these bioactive molecules have been discussed. Finally, we have provided an insight into how genome mining efforts are likely to expedite the discovery of novel antimicrobial compounds.

  18. Pathway Ranking for In-place Sediment Management (CU1209). Site 2 Report - Pearl Harbor

    DTIC Science & Technology

    2006-04-01

    type resistance cell. The probe is configured with two pairs of stainless steel electrodes, the outer pair through which a known current is imposed...the “bioinhibited” (no oxygen control) deployment at BPA . Vertical axis is dissolved oxygen concentration, and horizontal axis is sample record at 6...99 Table 5-7. BFSD results from site BPA . Numbers in the Flux Rate Confidence column indicate the

  19. Finding Lagrangian Structures via the Application of Braid Theory

    DTIC Science & Technology

    2010-10-16

    the horizontal plane is the physical domain and the vertical axis is time. These three dimensional...three dimensional strands are projected onto the plane containing the x-axis and time then Figure 2a becomes Figure 2b. The collection of strands make...trajectories shown in the physical plane . An “x” represents the initial condition of the trajectory and a dot represents the current position. (b) The

  20. Dispersal barriers and isolation among deep-sea mussel populations (Mytilidae: Bathymodiolus) from eastern Pacific hydrothermal vents.

    PubMed

    Won, Y; Young, C R; Lutz, R A; Vrijenhoek, R C

    2003-01-01

    Deep-sea hydrothermal vent species are widely dispersed among habitat islands found along the global mid-ocean ridge system. We examine factors that affect population structure, gene flow and isolation in vent-endemic mussels of the genus Bathymodiolus from the eastern Pacific Ocean. Mussels were sampled from localities including the Galapagos Rift (GAR, 0 degrees 48' N; 86 degrees 10' W) and the East Pacific Rise (EPR, 13 degrees N to 32 degrees S latitude) across a maximum distance of 4900 km. The sampled range crossed a series of topographical features that interrupt linear aspects of the ridge system, and it encompassed regions of strong cross-axis currents that could impede along-axis dispersal of mussel larvae. Examinations of mitochondrial DNA sequences and allozyme variation revealed significant barriers to gene flow along the ridge axis. All populations from the GAR and EPR from 13 degrees N to 11 degrees S were homogeneous genetically and appeared to experience unimpeded high levels of interpopulational gene flow. In contrast, mussels from north and south of the Easter Microplate were highly divergent (4.4%), possibly comprising sister-species that diverged after formation of the microplate approximately 4.5 Ma. Strong cross-axis currents associated with inflated bathymetry of the microplate region may reinforce isolation across this region.

  1. Rotational properties of planetary satellites

    NASA Technical Reports Server (NTRS)

    Peale, S. J.

    1991-01-01

    Properties of satellite rotation that are observable in principle, include the rotation period, the orientation of the spin axis relative to the orbit plane, precession of the spin axis due to gravitational torques, nonprincipal axis rotation or wobble, and deviations from uniform principle axis rotation or libration. Considerable order is observed in current satellite rotation states, and it is of interest to ascertain how this order came about and why some satellites do not conform to the dominant norm. There is a strong coupling between the spin and orbital motions that is primarily responsible for maintaining the ordered rotation states in most cases, but this coupling is equally responsible for destroying any chance of orderly rotation for Saturn's satellite Hyperion. Understanding the processes which constrain current rotation states as well as those of an evolutionary nature which could have brought the individual satellites to their observed rotation and orbit states allows us to sometimes infer interior properties of some satellite or even of its primary planet, although, attempts to deduce primordial rotation states are usually frustrated. The observed rotational properties of the planetary satellites are summarized, and the understanding of the processes maintaining and those leading to the observed states are outlined. Some of the inferences that can be drawn about intrinsic properties of the bodies themselves are indicated.

  2. Deposition and properties of Fe(Se,Te) thin films on vicinal CaF2 substrates

    NASA Astrophysics Data System (ADS)

    Bryja, Hagen; Hühne, Ruben; Iida, Kazumasa; Molatta, Sebastian; Sala, Alberto; Putti, Marina; Schultz, Ludwig; Nielsch, Kornelius; Hänisch, Jens

    2017-11-01

    We report on the growth of epitaxial Fe1+δ Se0.5Te0.5 thin films on 0°, 5°, 10°, 15° and 20° vicinal cut CaF2 single crystals by pulsed laser deposition. In situ electron and ex situ x-ray diffraction studies reveal a tilted growth of the Fe1+δ Se0.5Te0.5 films, whereby under optimized deposition conditions the c-axis alignment coincides with the substrate [001] tilted axis up to a vicinal angle of 10°. Atomic force microscopy shows a flat island growth for all films. From resistivity measurements in longitudinal and transversal directions, the ab- and c-axis components of resistivity are derived and the mass anisotropy parameter is determined. Analysis of the critical current density indicates that no effective c-axis correlated defects are generated by vicinal growth, and pinning by normal point core defects dominates. However, for H∣∣ab the effective pinning centers change from surface defects to point core defects near the superconducting transition due to the vicinal cut. Furthermore, we show in angular-dependent critical current density data a shift of the ab-planes maxima position with the magnetic field strength.

  3. The development of control and monitoring system on marine current renewable energy Case study: strait of Toyapakeh - Nusa Penida, Bali

    NASA Astrophysics Data System (ADS)

    Arief, I. S.; Suherman, I. H.; Wardani, A. Y.; Baidowi, A.

    2017-05-01

    Control and monitoring system is a continuous process of securing the asset in the Marine Current Renewable Energy. A control and monitoring system is existed each critical components which is embedded in Failure Mode Effect Analysis (FMEA) method. As the result, the process in this paper developed through a matrix sensor. The matrix correlated to critical components and monitoring system which supported by sensors to conduct decision-making.

  4. Search for Trapped Electrons and a Magnetic Moment at Mars by Mariner IV.

    PubMed

    O'gallagher, J J; Simpson, J A

    1965-09-10

    The Mariner IV spacecraft on 14-15 July 1965 passed within 9850 kilometers of Mars, carrying a solid-state charged-particle telescope which could detect electrons greater than 40 kiloelectron volts and protons greater than 1 million electron volts. The trajectory could have passed through a bow shock, a transition region, and a magnetospheric boundary where particles could be stably trapped for a wide range of Martian magnetic moments. No evidence of charged-particle radiation was found in any of these regions. In view of these results, an upper limit is established for the Martian magnetic moment provided it is assumed that the same physical processes leading to acceleration and trapping of electrons in Earth's magnetic field would be found in a Martian magnetic field. On this basis, the upper limit for the Martian magnetic moment is 0.1 percent that of Earth for a wide range of postulated orientations with respect to the rotational axis of Mars. The implications of these results for the physical and biological environment of Mars are briefly discussed.

  5. Numerical and experimental study of the 3D effect on connecting arm of vertical axis tidal current turbine

    NASA Astrophysics Data System (ADS)

    Guo, Wei; Kang, Hai-gui; Chen, Bing; Xie, Yu; Wang, Yin

    2016-03-01

    Vertical axis tidal current turbine is a promising device to extract energy from ocean current. One of the important components of the turbine is the connecting arm, which can bring about a significant effect on the pressure distribution along the span of the turbine blade, herein we call it 3D effect. However, so far the effect is rarely reported in the research, moreover, in numerical simulation. In the present study, a 3D numerical model of the turbine with the connecting arm was developed by using FLUENT software compiling the UDF (User Defined Function) command. The simulation results show that the pressure distribution along the span of blade with the connecting arm model is significantly different from those without the connecting arm. To facilitate the validation of numerical model, the laboratory experiment has been carried out by using three different types of NACA aerofoil connecting arm and circle section connecting arm. And results show that the turbine with NACA0012 connecting arm has the best start-up performance which is 0.346 m/s and the peak point of power conversion coefficient is around 0.33. A further study has been performed and a conclusion is drawn that the aerofoil and thickness of connecting arm are the most important factors on the power conversion coefficient of the vertical axis tidal current turbine.

  6. Anisotropic charge transport in large single crystals of π-conjugated organic molecules.

    PubMed

    Hourani, Wael; Rahimi, Khosrow; Botiz, Ioan; Koch, Felix Peter Vinzenz; Reiter, Günter; Lienerth, Peter; Heiser, Thomas; Bubendorff, Jean-Luc; Simon, Laurent

    2014-05-07

    The electronic properties of organic semiconductors depend strongly on the nature of the molecules, their conjugation and conformation, their mutual distance and the orientation between adjacent molecules. Variations of intramolecular distances and conformation disturb the conjugation and perturb the delocalization of charges. As a result, the mobility considerably decreases compared to that of a covalently well-organized crystal. Here, we present electrical characterization of large single crystals made of the regioregular octamer of 3-hexyl-thiophene (3HT)8 using a conductive-atomic force microscope (C-AFM) in air. We find a large anisotropy in the conduction with charge mobility values depending on the crystallographic orientation of the single crystal. The smaller conduction is in the direction of π-π stacking (along the long axis of the single crystal) with a mobility value in the order of 10(-3) cm(2) V(-1) s(-1), and the larger one is along the molecular axis (in the direction normal to the single crystal surface) with a mobility value in the order of 0.5 cm(2) V(-1) s(-1). The measured current-voltage (I-V) curves showed that along the molecular axis, the current followed an exponential dependence corresponding to an injection mode. In the π-π stacking direction, the current exhibits a space charge limited current (SCLC) behavior, which allows us to estimate the charge carrier mobility.

  7. Adversity-driven changes in hypothalamic-pituitary-adrenal axis functioning during adolescence. The trails study.

    PubMed

    Laceulle, Odilia M; Nederhof, Esther; van Aken, Marcel A G; Ormel, Johan

    2017-11-01

    The hypothalamic-pituitary-adrenal (HPA) axis has been proposed to be a key mechanism underlying the link between adversity and mental health, but longitudinal studies on adversity and HPA-axis functioning are scarce. Here, we studied adversity-driven changes in HPA-axis functioning during adolescence (N=141). HPA-axis functioning (basal cortisol, cortisol awakening response, anticipation of, reaction to and recovery after a stress task) was measured twice, at age 16 and 19. Adversity (i.e., social defeat and loss/illness) since age 16 was measured extensively with the Life Stress Interview at age 19. Adolescents who reported being exposed to social defeat showed increases in basal cortisol (ɳ 2 =0.029) and decreases in reaction to the stress task (ɳ 2 =0.030) from age 16-19, compared to their peers in the loss/illness and no stress group. The current study provides unique longitudinal data on the role of adversity in HPA-axis functioning. Evidence is provided that adversity can affect the body's neuroendocrine response to stress, dependent on the nature of both the HPA-measures and adverse events under study. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Camber Angle Inspection for Vehicle Wheel Alignments

    PubMed Central

    Young, Jieh-Shian; Hsu, Hong-Yi; Chuang, Chih-Yuan

    2017-01-01

    This paper introduces an alternative approach to the camber angle measurement for vehicle wheel alignment. Instead of current commercial approaches that apply computation vision techniques, this study aims at realizing a micro-control-unit (MCU)-based camber inspection system with a 3-axis accelerometer. We analyze the precision of the inspection system for the axis misalignments of the accelerometer. The results show that the axes of the accelerometer can be aligned to the axes of the camber inspection system imperfectly. The calibrations that can amend these axis misalignments between the camber inspection system and the accelerometer are also originally proposed since misalignments will usually happen in fabrications of the inspection systems. During camber angle measurements, the x-axis or z-axis of the camber inspection system and the wheel need not be perfectly aligned in the proposed approach. We accomplished two typical authentic camber angle measurements. The results show that the proposed approach is applicable with a precision of ±0.015∘ and therefore facilitates the camber measurement process without downgrading the precision by employing an appropriate 3-axis accelerometer. In addition, the measured results of camber angles can be transmitted via the medium such as RS232, Bluetooth, and Wi-Fi. PMID:28165365

  9. Metabotropic glutamate receptor-mediated signaling dampens the HPA axis response to restraint stress

    PubMed Central

    Evanson, Nathan K.; Herman, James P.

    2015-01-01

    Glutamate is an important neurotransmitter in regulation of the neural portion of hypothalamus-pituitary-adrenal (HPA) axis activity, and signals through ionotropic and metabotropic receptors. In the current studies we investigated the role of hypothalamic paraventricular group I metabotropic glutamate receptors in regulation of the HPA axis response to restraint stress in rats. Direct injection of the group I metabotropic glutamate receptor agonist 3,5-dihydroxyphenylglycine (DHPG) into the PVN prior to restraint leads to blunting of the HPA axis response in awake animals. Consistent with this result, infusion of the group I receptor antagonist hexyl-homoibotenic acid (HIBO) potentiates the HPA axis response to restraint. The excitatory effect of blocking paraventricular group I metabotropic glutamate signaling is blocked by co-administration of dexamethasone into the PVN. However, the inhibitory effect of DHPG is not affected by co-administration of the cannabinoid CB1 receptor antagonist AM-251 into the PVN. Together, these results suggest that paraventricular group I metabotropic glutamate receptor signaling acts to dampen HPA axis reactivity. This effect appears to be similar to the rapid inhibitory effect of glucocorticoids at the PVN, but is not mediated by endocannabinoid signaling. PMID:25701594

  10. Metabotropic glutamate receptor-mediated signaling dampens the HPA axis response to restraint stress.

    PubMed

    Evanson, Nathan K; Herman, James P

    2015-10-15

    Glutamate is an important neurotransmitter in the regulation of the neural portion of hypothalamus-pituitary-adrenal (HPA) axis activity, and signals through ionotropic and metabotropic receptors. In the current studies we investigated the role of hypothalamic paraventricular group I metabotropic glutamate receptors in the regulation of the HPA axis response to restraint stress in rats. Direct injection of the group I metabotropic glutamate receptor agonist 3,5-dihydroxyphenylglycine (DHPG) into the PVN prior to restraint leads to blunting of the HPA axis response in awake animals. Consistent with this result, infusion of the group I receptor antagonist hexyl-homoibotenic acid (HIBO) potentiates the HPA axis response to restraint. The excitatory effect of blocking paraventricular group I metabotropic glutamate signaling is blocked by co-administration of dexamethasone into the PVN. However, the inhibitory effect of DHPG is not affected by co-administration of the cannabinoid CB1 receptor antagonist AM-251 into the PVN. Together, these results suggest that paraventricular group I metabotropic glutamate receptor signaling acts to dampen HPA axis reactivity. This effect appears to be similar to the rapid inhibitory effect of glucocorticoids at the PVN, but is not mediated by endocannabinoid signaling. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Marine-derived angiogenesis inhibitors for cancer therapy.

    PubMed

    Wang, Ying-Qing; Miao, Ze-Hong

    2013-03-15

    Angiogenesis inhibitors have been successfully used for cancer therapy in the clinic. Many marine-derived natural products and their analogues have been reported to show antiangiogenic activities. Compared with the drugs in the clinic, these agents display interesting characteristics, including diverse sources, unique chemical structures, special modes of action, and distinct activity and toxicity profiles. This review will first provide an overview of the current marine-derived angiogenesis inhibitors based on their primary targets and/or mechanisms of action. Then, the marine-derived antiangiogenic protein kinase inhibitors will be focused on. And finally, the clinical trials of the marine-derived antiangiogenic agents will be discussed, with special emphasis on their application potentials, problems and possible coping strategies in their future development as anticancer drugs.

  12. Influence of fishing activity over the marine debris composition close to coastal jetty.

    PubMed

    Farias, Eduardo G G; Preichardt, Paulo R; Dantas, David V

    2018-04-23

    Worldwide, the marine debris emissions have been provoking impacts in ecosystems, generating massive mortality of different species with commercial interest. In South America, we have a lack of studies to verify the marine debris composition in transitional environments such as adjacent regions of coastal jetties. These are hydraulic engineering constructions used to maintain the navigation channel access between the sea-estuarine interface and are also used by teleost fishes, crustaceans, and mollusks like artificial shelters (reefs), being excellent fishing grounds. Therefore, the present study was devoted to qualitatively evaluate the composition of marine debris in an internal jetty portion of a Laguna Estuarine System (LES) located in South America (Brazil). Six hundred freediving were conducted to collect marine debris in the study region. The in situ campaigns were performed in 2016 during all spring season (sand substrata) in four distinct zones with 26,400 m 2 each one covering almost all adjacent jetty extension, to evaluate possible spatial changes in the marine debris composition. All material obtained was identified, measured, weighed, and ordered in eight groups, with six groups being related to the fishing activity and two groups related to the tourism/community in the study region. So, it was possible to observe possible relations between the marine debris distribution to artisanal and recreational local fishing. After 600 freediving sampling efforts, 2142 marine debris items were obtained, totaling close to 100 kg of solid waste removed from the inner portion of the coastal jetty. Notably, 1752 units (50 kg) of fishing leads were collected being this item the main marine debris residue found in the four sampled areas, corresponding to nearly 50% of the total weight of the collected waste. Ninety-eight percent of marine debris were derived from the local fishing activities, and just 2% were derived from tourism/community. Considering the total contribution related to fishing, 83% of the marine debris were composed by lead (sinkers) adopted by recreational and artisanal fishing. Notably, the catch activity in this region has a close influence over the marine debris composition. Reductions of marine debris emissions derived from the fishing activities have been a global challenge, once this problem is occurring in practically all marine and estuarine environments under the anthropic action. The presence of marine debris changes the local landscape and can provoke serious environmental problems, such as ghost fishing that affects a wide variability of marine mammals, birds, and fishes. Most of marine debris collected came from recreational and artisanal fishing, being the fishing leads the most prominent material, especially in sector 4. This fact is possibly related to the intense mullet fishing using cast nets, usual in this sample area. In the other sectors, there was a great predominance of grapnel fishing leads, widely adopted by recreational fishermen in open water environments. The "fingernails" present in these fishing leads ensure the sinking of the line for a specific location independently of possible flow oscillations of the tidal current and/or currents generated by winds. The massive quantity of fishing leads into the sectors is a dangerous fact. Notably, lead is a heavy, non-biodegradable, and extremely toxic metal that, due to the anthropogenic activities, has been increasing around the world. Future efforts in our study region should evaluate the seasonal marine debris composition to observe possible changes along the different seasons of the year. In this way, it would be possible to infer quantitatively the emission of marine debris derived from the fishing activity, assessing its impacts and enabling the adoption of environmental management strategies. This effort adopted a qualitative analysis, serving to show the current situation of this region that we now know to be vulnerable to the presence of marine debris derived from the fishing activity.

  13. How Connecting Sediment Transport Between Environments Solves First-Order Questions Regarding Construction of the Land- and Seascape Recorded by the Permian Brushy Canyon Fm., West Texas, USA

    NASA Astrophysics Data System (ADS)

    Mohrig, D. C.; Ustipak, K.

    2016-12-01

    Exposures in the Guadalupe and Delaware mountains together with well logs and core from the Delaware Basin capture a system-wide picture of the stratigraphy defining the terrestrial, shallow marine, basin slope and basin floor environments associated with the Permian Brushy Canyon Formation. Patterns of erosion and styles of deposition characterizing any one of these environments cannot be fully understood without explicit consideration of sediment transport in the adjacent environments. Properties of an inherited basin margin and slope are particularly important to unraveling the transport histories in the linked terrestrial - to - deep marine environments defining the Brushy Canyon Fm. A one-dimensional turbidity current model will be used to show that the inherited submarine slope of about six degrees is steep enough that all sand-transporting currents are erosional down its length. This slope segment detaches the terrestrial and shallow marine environments from the deeper marine environments and decreases the potential for sediment accumulation in the former. All sediment transported to the brink of the basin slope is efficiently moved to deeper water, promoting a tendency for very little sediment to be preserved in the terrestrial environment; a property of the Brushy Canyon system that has spurred on considerable debate and speculation amongst geoscientists studying the formation. The steep inherited slope and its ability to generate erosional sandy turbidity currents also provides an explanation for the high relative fraction of thin-bedded, mud-rich deposits that are present in the most proximal deep marine setting. Again, a one-dimensional turbidity current model is used to show that only very dilute, muddy currents are expected to accumulate in significant quantity at this position in the long profile of the system. Coarser sediment load is confined to and efficiently transported through erosionally based channels onto the basin floor. Finally, the observed spatial trends in sediment erosion over the proximal 20 - 30 km of the basin floor and net sedimentation out to distances approaching 160 km from the shelf edge will be explored and further quantified using the one-dimensional numerical model for turbidity currents.

  14. Commercial Mobile Device Technology Implementation Implications in United States Marine Corps Processes: A Case Study Approach

    DTIC Science & Technology

    2016-09-01

    innovative solutions to current problems. One such innovation that could potentially save the Marine Corps money , while increasing its ability to prepare...the Marine Corps money , while increasing its ability to prepare for and conduct its mission, is the use of commercial mobile devices. This research...problems. One such innovation that could potentially save the USMC money , while increasing the ability to prepare for and conduct its mission is the

  15. DOD Financial Management: Actions Are Needed on Audit Issues Related to the Marine Corps 2012 Schedule of Budgetary Activity

    DTIC Science & Technology

    2015-07-01

    Requisitioning and Issue Procedures OIG Office of Inspector General OMB Office of Management and Budget QMD Quantitative Methods Division SABRS ...Reporting System ( SABRS )—and transactions recorded in the current year may be improperly recorded to appropriations not included in the Marine Corps...Accountability System (DCAS)55 to the Marine Corps’ SABRS general ledger system and through the Defense Departmental Reporting Systems (DDRS) to financial

  16. FINAL TECHNICAL REPORT: Underwater Active Acoustic Monitoring Network For Marine And Hydrokinetic Energy Projects

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

    Stein, Peter J.; Edson, Patrick L.

    2013-12-20

    This project saw the completion of the design and development of a second generation, high frequency (90-120 kHz) Subsurface-Threat Detection Sonar Network (SDSN). The system was deployed, operated, and tested in Cobscook Bay, Maine near the site the Ocean Renewable Power Company TidGen™ power unit. This effort resulted in a very successful demonstration of the SDSN detection, tracking, localization, and classification capabilities in a high current, MHK environment as measured by results from the detection and tracking trials in Cobscook Bay. The new high frequency node, designed to operate outside the hearing range of a subset of marine mammals, wasmore » shown to detect and track objects of marine mammal-like target strength to ranges of approximately 500 meters. This performance range results in the SDSN system tracking objects for a significant duration - on the order of minutes - even in a tidal flow of 5-7 knots, potentially allowing time for MHK system or operator decision-making if marine mammals are present. Having demonstrated detection and tracking of synthetic targets with target strengths similar to some marine mammals, the primary hurdle to eventual automated monitoring is a dataset of actual marine mammal kinematic behavior and modifying the tracking algorithms and parameters which are currently tuned to human diver kinematics and classification.« less

  17. A decade of the World Register of Marine Species – General insights and experiences from the Data Management Team: Where are we, what have we learned and how can we continue?

    PubMed Central

    Vanhoorne, Bart; Decock, Wim; Vranken, Sofie; Lanssens, Thomas; Dekeyzer, Stefanie; Verfaille, Kevin; Horton, Tammy; Kroh, Andreas; Hernandez, Francisco; Mees, Jan

    2018-01-01

    The World Register of Marine Species (WoRMS) celebrated its 10th anniversary in 2017. WoRMS is a unique database: there is no comparable global database for marine species, which is driven by a large, global expert community, is supported by a Data Management Team and can rely on a permanent host institute, dedicated to keeping WoRMS online. Over the past ten years, the content of WoRMS has grown steadily, and the system currently contains more than 242,000 accepted marine species. WoRMS has not yet reached completeness: approximately 2,000 newly described species per year are added, and editors also enter the remaining missing older names–both accepted and unaccepted–an effort amounting to approximately 20,000 taxon name additions per year. WoRMS is used extensively, through different channels, indicating that it is recognized as a high-quality database on marine species information. It is updated on a daily basis by its Editorial Board, which currently consists of 490 taxonomic and thematic experts located around the world. Owing to its unique qualities, WoRMS has become a partner in many large-scale initiatives including OBIS, LifeWatch and the Catalogue of Life, where it is recognized as a high-quality and reliable source of information for marine taxonomy. PMID:29624577

  18. Pharmaceutically active secondary metabolites of marine actinobacteria.

    PubMed

    Manivasagan, Panchanathan; Venkatesan, Jayachandran; Sivakumar, Kannan; Kim, Se-Kwon

    2014-04-01

    Marine actinobacteria are one of the most efficient groups of secondary metabolite producers and are very important from an industrial point of view. Many representatives of the order Actinomycetales are prolific producers of thousands of biologically active secondary metabolites. Actinobacteria from terrestrial sources have been studied and screened since the 1950s, for many important antibiotics, anticancer, antitumor and immunosuppressive agents. However, frequent rediscovery of the same compounds from the terrestrial actinobacteria has made them less attractive for screening programs in the recent years. At the same time, actinobacteria isolated from the marine environment have currently received considerable attention due to the structural diversity and unique biological activities of their secondary metabolites. They are efficient producers of new secondary metabolites that show a range of biological activities including antibacterial, antifungal, anticancer, antitumor, cytotoxic, cytostatic, anti-inflammatory, anti-parasitic, anti-malaria, antiviral, antioxidant, anti-angiogenesis, etc. In this review, an evaluation is made on the current status of research on marine actinobacteria yielding pharmaceutically active secondary metabolites. Bioactive compounds from marine actinobacteria possess distinct chemical structures that may form the basis for synthesis of new drugs that could be used to combat resistant pathogens. With the increasing advancement in science and technology, there would be a greater demand for new bioactive compounds synthesized by actinobacteria from various marine sources in future. Copyright © 2013 Elsevier GmbH. All rights reserved.

  19. Law and Marine Science

    ERIC Educational Resources Information Center

    Bockrath, Joseph

    1976-01-01

    The University of Delaware Marine Studies has implemented courses in coastal zone law and policy and maritime law. The courses attempt to integrate the scientist's or engineer's work with public policy formation. The program emphasizes historical and current issues and the economic, cultural, and political forces operating in decision-making…

  20. 40 CFR 112.2 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... appropriate), ice conditions, temperatures, weather-related visibility, and currents within the area in which... the container. Animal fat means a non-petroleum oil, fat, or grease of animal, fish, or marine mammal...-based, including but not limited to: Fats, oils, and greases of animal, fish, or marine mammal origin...

  1. 76 FR 42116 - National Policy for Distinguishing Serious From Non-Serious Injuries of Marine Mammals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-18

    ... transparent process for effective conservation of marine mammal stocks and management of human activities... performance under existing processes, and gather the best available and current scientific information... The draft Procedural Directive describes the annual process for making and documenting injury...

  2. PROSPECTS ON BEHAVIORAL STUDIES OF MARINE AND FRESHWATER TOXINS.

    EPA Science Inventory

    This manuscript is based in large part on an invited presentation. The manuscript provides a brief overview of the growing issue of the human-health and environmental impact of a variety of toxins of marine and freshwater origin, the current (generally crude) state of behavioral...

  3. Ocean Data Interoperability Platform (ODIP): developing a common framework for marine data management on a global scale

    NASA Astrophysics Data System (ADS)

    Glaves, Helen; Schaap, Dick

    2016-04-01

    The increasingly ocean basin level approach to marine research has led to a corresponding rise in the demand for large quantities of high quality interoperable data. This requirement for easily discoverable and readily available marine data is currently being addressed by initiatives such as SeaDataNet in Europe, Rolling Deck to Repository (R2R) in the USA and the Australian Ocean Data Network (AODN) with each having implemented an e-infrastructure to facilitate the discovery and re-use of standardised multidisciplinary marine datasets available from a network of distributed repositories, data centres etc. within their own region. However, these regional data systems have been developed in response to the specific requirements of their users and in line with the priorities of the funding agency. They have also been created independently of the marine data infrastructures in other regions often using different standards, data formats, technologies etc. that make integration of marine data from these regional systems for the purposes of basin level research difficult. Marine research at the ocean basin level requires a common global framework for marine data management which is based on existing regional marine data systems but provides an integrated solution for delivering interoperable marine data to the user. The Ocean Data Interoperability Platform (ODIP/ODIP II) project brings together those responsible for the management of the selected marine data systems and other relevant technical experts with the objective of developing interoperability across the regional e-infrastructures. The commonalities and incompatibilities between the individual data infrastructures are identified and then used as the foundation for the specification of prototype interoperability solutions which demonstrate the feasibility of sharing marine data across the regional systems and also with relevant larger global data services such as GEO, COPERNICUS, IODE, POGO etc. The potential impact for the individual regional data infrastructures of implementing these prototype interoperability solutions is also being evaluated to determine both the technical and financial implications of their integration within existing systems. These impact assessments form part of the strategy to encourage wider adoption of the ODIP solutions and approach beyond the current scope of the project which is focussed on regional marine data systems in Europe, Australia, the USA and, more recently, Canada.

  4. Locomotion and the Cost of Hunting in Large, Stealthy Marine Carnivores.

    PubMed

    Williams, Terrie M; Fuiman, Lee A; Davis, Randall W

    2015-10-01

    Foraging by large (>25 kg), mammalian carnivores often entails cryptic tactics to surreptitiously locate and overcome highly mobile prey. Many forms of intermittent locomotion from stroke-and-glide maneuvers by marine mammals to sneak-and-pounce behaviors by terrestrial canids, ursids, and felids are involved. While affording proximity to vigilant prey, these tactics are also associated with unique energetic costs and benefits to the predator. We examined the energetic consequences of intermittent locomotion in mammalian carnivores and assessed the role of these behaviors in overall foraging efficiency. Behaviorally-linked, three-axis accelerometers were calibrated to provide instantaneous locomotor behaviors and associated energetic costs for wild adult Weddell seals (Leptonychotes weddellii) diving beneath the Antarctic ice. The results were compared with previously published values for other marine and terrestrial carnivores. We found that intermittent locomotion in the form of extended glides, burst-and-glide swimming, and rollercoaster maneuvers while hunting silverfish (Pleuragramma antarcticum) resulted in a marked energetic savings for the diving seals relative to continuously stroking. The cost of a foraging dive by the seals decreased by 9.2-59.6%, depending on the proportion of time gliding. These energetic savings translated into exceptionally low transport costs during hunting (COTHUNT) for diving mammals. COTHUNT for Weddell seals was nearly six times lower than predicted for large terrestrial carnivores, and demonstrates the importance of turning off the propulsive machinery to facilitate cost-efficient foraging in highly active, air-breathing marine predators. © The Author 2015. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

  5. Marine self potential and CSEM measurements using an autonomous underwater vehicle

    NASA Astrophysics Data System (ADS)

    Constable, S.; Kowalczyk, P.; Bloomer, S.

    2017-12-01

    Marine self potential (SP) and controlled source EM (CSEM) measurements are commonly made using instruments towed close to the seafloor, which requires dedicated ship time, is limited to slow speeds, and is subject to navigation errors of 5 to 10 m. An alternative is to mount SP and CSEM sensors on an autonomous underwater vehicle (AUV). We tested this with a pilot study in the Iheya area of the Okinawa Trough, off Japan, using an ISE Explorer-class AUV operated by Fukada Salvage and Marine Works and equipped with a Scripps CSEM receiver system. Parts of this prospect have documented hydrothermal venting and seafloor massive sulfide (SMS) deposits. CSEM signals were generated by deploying battery-powered seafloor transmitters, which emitted 20 amps, alternately every 30 seconds on orthogonal, 10 m antennas. CSEM signals were recorded by 3-axis AC-coupled sensors on the AUV as it flew a pattern 70 m above the seafloor around the transmitters. By transmitting two slightly different frequencies, two or more transmitters can broadcast simultaneously. Measurements were made at the same time using DC-coupled electric field amplifiers, from which self potentials were estimated using regularized inversion, yielding negative anomalies of 10 to 25 mV. Modeling suggests that the anomalies are localized and close to the seafloor. Apparent conductivities as high as 30 S/m were fit to the CSEM data, which strongly suggests that SMS mineralization is associated with the SP anomalies, although it is possible the causative mechanism is at least partly due to hydrothermal venting. In either case, we have demonstrated that AUV-mounted instrument systems are an efficient, effective, and low noise means of collecting marine CSEM and SP data. The entire data set was collected in a single day on station with a 10-hour AUV deployment.

  6. Mariner Jupiter/Saturn 1977 preliminary mission design.

    NASA Technical Reports Server (NTRS)

    Bourke, R. D.; Miles, R. F.; Penzo, P. A.; Van Dillen, S. L.; Wallace, R. A.

    1972-01-01

    Current plans of NASA are to take advantage of the 1977 launch opportunity by sending a Mariner class spacecraft on a gravity assisted flyby of Jupiter which will then continue on to Saturn. The background of this Mariner Jupiter-Saturn 77 Project is reviewed and science objectives for this mission as currently adapted are given. This paper illustrates properties of the Jupiter-Saturn opportunities between 1976 and 1980 to give context to the 1977 opportunity. Details of the possibilities for the 1977 launch are shown along with constraints and example candidate trajectories. Options include close flybys and/or occultations of the satellites at Jupiter and Saturn, penetration of Saturn's rings, and various occultations of the planets. A short discussion of other factors, such as navigation and planetary quarantine (documented elsewhere) are included.

  7. A data acquisition system for marine and ecological research.

    NASA Technical Reports Server (NTRS)

    Johnson, R. A.

    1971-01-01

    Description of a self-contained portable data acquisition system for use in marine and ecological research. The compact lightweight data acquisition system is capable of recording 14 variables in its present configuration and is suitable for use in either a boat, pickup truck, or light aircraft. This system will provide the acquisition of reliable data on the structure of the environment and the effect of man-made and natural activities on the observed phenomenon. Utilizing both self-contained analog recording and a telemetry transmitter for real-time digital readout and recording, the prototype system has undergone extensive testing. Currently undergoing component performance upgrading, the prototype system has been utilized in several environmental science investigations associated with air pollution investigations and weather modification and is currently being used for marine data acquisition.

  8. The Foraging Ecology of the Endangered Cape Verde Shearwater, a Sentinel Species for Marine Conservation off West Africa.

    PubMed

    Paiva, Vitor H; Geraldes, Pedro; Rodrigues, Isabel; Melo, Tommy; Melo, José; Ramos, Jaime A

    2015-01-01

    Large Marine Ecosystems such as the Canary Current system off West Africa sustains high abundance of small pelagic prey, which attracts marine predators. Seabirds are top predators often used as biodiversity surrogates and sentinel species of the marine ecosystem health, thus frequently informing marine conservation planning. This study presents the first data on the spatial (GPS-loggers) and trophic (stable isotope analysis) ecology of a tropical seabird-the endangered Cape Verde shearwater Calonectris edwardsii-during both the incubation and the chick-rearing periods of two consecutive years. This information was related with marine environmental predictors (species distribution models), existent areas of conservation concern for seabirds (i.e. marine Important Bird Areas; marine IBAs) and threats to the marine environment in the West African areas heavily used by the shearwaters. There was an apparent inter-annual consistency on the spatial, foraging and trophic ecology of Cape Verde shearwater, but a strong alteration on the foraging strategies of adult breeders among breeding phases (i.e. from incubation to chick-rearing). During incubation, birds mostly targeted a discrete region off West Africa, known by its enhanced productivity profile and thus also highly exploited by international industrial fishery fleets. When chick-rearing, adults exploited the comparatively less productive tropical environment within the islands of Cape Verde, at relatively close distance from their breeding colony. The species enlarged its trophic niche and increased the trophic level of their prey from incubation to chick-rearing, likely to provision their chicks with a more diversified and better quality diet. There was a high overlap between the Cape Verde shearwaters foraging areas with those of European shearwater species that overwinter in this area and known areas of megafauna bycatch off West Africa, but very little overlap with existing Marine Important Bird Areas. Further investigation on the potential nefarious effects of fisheries on seabird communities exploiting the Canary Current system off West Africa is needed. Such negative effects could be alleviated or even dissipated if the 'fisheries-conservation hotspots' identified for the region, would be legislated as Marine Protected Areas.

  9. The Foraging Ecology of the Endangered Cape Verde Shearwater, a Sentinel Species for Marine Conservation off West Africa

    PubMed Central

    Paiva, Vitor H.; Geraldes, Pedro; Rodrigues, Isabel; Melo, Tommy; Melo, José; Ramos, Jaime A.

    2015-01-01

    Large Marine Ecosystems such as the Canary Current system off West Africa sustains high abundance of small pelagic prey, which attracts marine predators. Seabirds are top predators often used as biodiversity surrogates and sentinel species of the marine ecosystem health, thus frequently informing marine conservation planning. This study presents the first data on the spatial (GPS-loggers) and trophic (stable isotope analysis) ecology of a tropical seabird—the endangered Cape Verde shearwater Calonectris edwardsii–during both the incubation and the chick-rearing periods of two consecutive years. This information was related with marine environmental predictors (species distribution models), existent areas of conservation concern for seabirds (i.e. marine Important Bird Areas; marine IBAs) and threats to the marine environment in the West African areas heavily used by the shearwaters. There was an apparent inter-annual consistency on the spatial, foraging and trophic ecology of Cape Verde shearwater, but a strong alteration on the foraging strategies of adult breeders among breeding phases (i.e. from incubation to chick-rearing). During incubation, birds mostly targeted a discrete region off West Africa, known by its enhanced productivity profile and thus also highly exploited by international industrial fishery fleets. When chick-rearing, adults exploited the comparatively less productive tropical environment within the islands of Cape Verde, at relatively close distance from their breeding colony. The species enlarged its trophic niche and increased the trophic level of their prey from incubation to chick-rearing, likely to provision their chicks with a more diversified and better quality diet. There was a high overlap between the Cape Verde shearwaters foraging areas with those of European shearwater species that overwinter in this area and known areas of megafauna bycatch off West Africa, but very little overlap with existing Marine Important Bird Areas. Further investigation on the potential nefarious effects of fisheries on seabird communities exploiting the Canary Current system off West Africa is needed. Such negative effects could be alleviated or even dissipated if the ‘fisheries-conservation hotspots’ identified for the region, would be legislated as Marine Protected Areas. PMID:26436804

  10. Climate impacts on global hot spots of marine biodiversity.

    PubMed

    Ramírez, Francisco; Afán, Isabel; Davis, Lloyd S; Chiaradia, André

    2017-02-01

    Human activities drive environmental changes at scales that could potentially cause ecosystem collapses in the marine environment. We combined information on marine biodiversity with spatial assessments of the impacts of climate change to identify the key areas to prioritize for the conservation of global marine biodiversity. This process identified six marine regions of exceptional biodiversity based on global distributions of 1729 species of fish, 124 marine mammals, and 330 seabirds. Overall, these hot spots of marine biodiversity coincide with areas most severely affected by global warming. In particular, these marine biodiversity hot spots have undergone local to regional increasing water temperatures, slowing current circulation, and decreasing primary productivity. Furthermore, when we overlapped these hot spots with available industrial fishery data, albeit coarser than our estimates of climate impacts, they suggest a worrying coincidence whereby the world's richest areas for marine biodiversity are also those areas mostly affected by both climate change and industrial fishing. In light of these findings, we offer an adaptable framework for determining local to regional areas of special concern for the conservation of marine biodiversity. This has exposed the need for finer-scaled fishery data to assist in the management of global fisheries if the accumulative, but potentially preventable, effect of fishing on climate change impacts is to be minimized within areas prioritized for marine biodiversity conservation.

  11. Seasonal Variation in Sea Turtle Density and Abundance in the Southeast Florida Current and Surrounding Waters.

    PubMed

    Bovery, Caitlin M; Wyneken, Jeanette

    2015-01-01

    Assessment and management of sea turtle populations is often limited by a lack of available data pertaining to at-sea distributions at appropriate spatial and temporal resolutions. Assessing the spatial and temporal distributions of marine turtles in an open system poses both observational and analytical challenges due to the turtles' highly migratory nature. Surface counts of marine turtles in waters along the southern part of Florida's east coast were made in and adjacent to the southeast portion of the Florida Current using standard aerial surveys during 2011 and 2012 to assess their seasonal presence. This area is of particular concern for sea turtles as interest increases in offshore energy developments, specifically harnessing the power of the Florida Current. While it is understood that marine turtles use these waters, here we evaluate seasonal variation in sea turtle abundance and density over two years. Density of sea turtles observed within the study area ranged from 0.003 turtles km-2 in the winter of 2011 to 0.064 turtles km-2 in the spring of 2012. This assessment of marine turtles in the waters off southeast Florida quantifies their in-water abundance across seasons in this area to establish baselines and inform future management strategies of these protected species.

  12. Regularized Biot–Savart Laws for Modeling Magnetic Flux Ropes

    NASA Astrophysics Data System (ADS)

    Titov, Viacheslav S.; Downs, Cooper; Mikić, Zoran; Török, Tibor; Linker, Jon A.; Caplan, Ronald M.

    2018-01-01

    Many existing models assume that magnetic flux ropes play a key role in solar flares and coronal mass ejections (CMEs). It is therefore important to develop efficient methods for constructing flux-rope configurations constrained by observed magnetic data and the morphology of the pre-eruptive source region. For this purpose, we have derived and implemented a compact analytical form that represents the magnetic field of a thin flux rope with an axis of arbitrary shape and circular cross-sections. This form implies that the flux rope carries axial current I and axial flux F, so that the respective magnetic field is the curl of the sum of axial and azimuthal vector potentials proportional to I and F, respectively. We expressed the vector potentials in terms of modified Biot–Savart laws, whose kernels are regularized at the axis in such a way that, when the axis is straight, these laws define a cylindrical force-free flux rope with a parabolic profile for the axial current density. For the cases we have studied so far, we determined the shape of the rope axis by following the polarity inversion line of the eruptions’ source region, using observed magnetograms. The height variation along the axis and other flux-rope parameters are estimated by means of potential-field extrapolations. Using this heuristic approach, we were able to construct pre-eruption configurations for the 2009 February 13 and 2011 October 1 CME events. These applications demonstrate the flexibility and efficiency of our new method for energizing pre-eruptive configurations in simulations of CMEs.

  13. Eddy current position indicating apparatus for measuring displacements of core components of a liquid metal nuclear reactor

    DOEpatents

    Day, Clifford K.; Stringer, James L.

    1977-01-01

    Apparatus for measuring displacements of core components of a liquid metal fast breeder reactor by means of an eddy current probe. The active portion of the probe is located within a dry thimble which is supported on a stationary portion of the reactor core support structure. Split rings of metal, having a resistivity significantly different than sodium, are fixedly mounted on the core component to be monitored. The split rings are slidably positioned around, concentric with the probe and symmetrically situated along the axis of the probe so that motion of the ring along the axis of the probe produces a proportional change in the probes electrical output.

  14. Characterisation of impacts on the environment of an idealised offshore wind farm foundation, under waves and the combination of waves and currents

    NASA Astrophysics Data System (ADS)

    García-Hermosa, Isabel; Abcha, Nizar; Brossard, Jérôme; Bennis, Anne-Claire; Ezersky, Alexander; Gross, Marcus; Iglesias, Gregorio; Magar, Vanesa; Miles, Jon; Mouazé, Dominique; Perret, Gaële; Pinon, Grégory; Rivier, Aurélie; Rogan, Charlie; Simmonds, David

    2015-04-01

    Offshore wind technology is currently the most widespread and advanced source of marine renewable energy. Offshore wind farms populate waters through the North Sea and the English Channel. The UK and French governments devised deadlines to achieve percentages of electricity from renewable sources by 2020, these deadlines and the direct translation of land based wind farm technology to the offshore environment resulted in the rapid expansion of the offshore wind energy. New wind farms have been designed with a larger number of masts and are moving from shallow offshore banks to deeper waters and in order to produce more power the diameters of monopoles masts are becoming larger to support larger turbines. The three-partner EU INTERREG funded project OFELIA (http://www.interreg-ofelia.eu/) aims to establish a cross-channel (between the UK and France) research collaboration to improve understanding of the environmental impacts of offshore wind farm foundations. The objective of the present study is to characterise changes in the hydrodynamics and sea bed in the vicinity of an offshore wind farm mast and in the wake area under wave and wave-current conditions corresponding to events in the French wind farm site of Courseulles-sur-mer (offshore of Lower Normandy, in the English Channel). Experiments were carried out in two laboratory facilities: a wave flume of 35 m long, 0.9 m wide and 1.2 m in depth with regular and irregular waves (García-Hermosa et al., 2014); and a wave and current flume of 17 m long, 0.5 m wide and 0.4 m depth with regular waves, currents from 180° to the waves and a mobile bed (Gunnoo et al., 2014). Flow velocity measurements were taken with an Acoustic Dopple Velocimeter (ADV) at various points around the cylinder and Particle Image Velocitmetry (PIV) techniques were applied to larger areas upstream and downstream of the cylinder. During the assessment of waves and currents' effects on the bed evolution were assessed using a laser and camera system photographing the bed (Marin & Ezersky, 2007, and Jarno-Druaux et al., 2004). Velocity fields, and flow structures around the cylinder at low KC numbers (KC~1) were characterised and parameters such as vorticity, turbulent kinetic energy and bed shear stresses derived where possible. During the experiments vortex structures with a horizontal axis were observed in the vicinity of the cylinder and the bed even at low KC. The Keulegan-Carpenter number (KC) is defined as: KC = UmT- D, where Um is the bottom orbital velocity, T the peak period and D the pile diameter. As part of the project, the findings from the experiments fed into a regional numerical modelling (Rivier et al., 2014) to improve parametrisation of the representation of the within-cell processes (local to the mast). References García-Hermosa, M. I., Brossard, J., Cohen, Z., Perret, G. (2014). Experimental characterisation of wave induced flow fields due to an offshore wind farm mast. First International Conference on Renewable Energies Offshore (RENEW) Lisbon, Portugal. November 2014. Gunnoo, H., Abcha, N., Mouazé, D., Ezersky, A., García-Hermosa, M. I. (2014). Laboratory simulation of resonance amplification of the hydrodynamic fields in the vicinity of wind farm masts. Proceedings of the First International Conference on Renewable Energies Offshore (RENEW) Lisbon, Portugal. November 2014. Jarno-Druaux, A., Brossard, J., Marin, F. (2004). Dynamical evolution of ripples in a wave channel, European Journal of Mechanics B/Fluids 23: 695-708. Marin, F. and Ezersky, A. B. (2007). Formation dynamics of sand bedforms under solitons and bound states of solitons in a wave flume used in resonant mode. European Journal of Mechanics - B/Fluids, Elsevier, 2008, 27 (3), pp.251-267. Rivier, A., Bennis, A.-C., Pinon, G., Gross, M., Magar, V. (2014). Regional numerical modelling of offshore monopile wind turbine impacts on hydrodynamics and sediment transport. Proceeding of the 1st International Conference on Renewable Energies Offshore (RENEW) Lisbon, Portugal. November 2014.

  15. Distribution of Hydrothermal Activity at the Lau ISS: Possible Controlling Parameters

    NASA Astrophysics Data System (ADS)

    Martinez, F.; Baker, E. T.; Resing, J. A.; Edwards, M. H.; Walker, S. L.; Buck, N.

    2008-12-01

    Seismic tomographic studies of intermediate to fast spreading rate mid-ocean ridges (MORs) interpret zones of rapid crustal cooling a few (3-4) km off axis surrounding the axial seismic low velocity zone (LVZ). These zones of rapid cooling also broadly correlate with the initiation and growth of large abyssal hill faults. The close association of both high thermal gradients and development of fault permeability at crustal scales suggests the hypothesis that these areas may be favorable locations for off-axis high temperature hydrothermal activity. In March-May 2008 on R/V Kilo Moana we conducted a near-bottom sidescan sonar and oceanographic survey along the Eastern Lau Spreading Center (ELSC) and Valu Fa Ridge (VFR) in the Lau back-arc basin to map the distribution of hydrothermal activity within this region. The survey utilized the deep-towed DSL120A (IMI120) sonar, an array of miniature autonomous plume recorders (MAPRs) attached to the tow cable and tethered beneath the sonar's depressor weight, an in situ chemical scanner (VISA) and 23 CTD hydrocasts (see Baker et al., this session). At the ELSC the survey spanned ~100 x 10 km area encompassing the ABE, Tow Cam and Kilo Moana vent fields with ~ 1 km spaced lines overall and ~500 m spaced lines in the area of the ABE vent field. On the VFR the survey spanned a distance of ~100 km along axis by ~5 km across axis with 700 m spaced lines encompassing the Vai Lili, Mariner and Tui Malila vent sites. Initial results identified particle plumes, indicative of high temperature venting, only within about a km of the ridge axis at the ELSC and VFR with possible diffuse venting indicated by MAPR oxidation-reduction potential (ORP) measurements at flank sites at VFR. The expanded sonar coverage better defines the volcano-tectonic context of the hydrothermal signals and previously mapped vent sites. Initial results suggest, however, no high-T venting more than about 1 km from the ridge axis, an apparently negative test of the above hypothesis. This may suggest that hydrothermal fluids are efficiently channeled to the axis even if cooling off-axis crustal regions. Alternatively, at the back-arc VFR/ELSC subduction controls on magmatic productivity may play an important role in modifying the usual relationships observed at MORs among spreading rate, seismic low velocity zone width, faulting, sedimentation and hydrothermal activity. For example, the fast spreading ELSC is magmatically deficient for its spreading rate, forms a deep faulted axial floor and has no continuous axial magma lens seismic reflector. This may lead to a narrower LVZ at the ELSC relative to MORs spreading at the same rate. At the intermediate rate and arc- proximal VFR excess magmatic productivity and volatile-rich volcanics form a peaked shallow axis, few flanking faults and a sediment drape of volcaniclastics from the ridge axis (and nearby arc volcanoes). These effects may act to suppress fault-related permeability on ridge flanks or may rapidly blanket ridge-flanking hydrothermal systems. Some of these issues may be further clarified when planned seismic tomographic and moored hydrophone studies are carried out beginning next year at the ELSC/VFR.

  16. Role of the Hypothalamic-Pituitary-Adrenal Axis in Developmental Programming of Health and Disease

    PubMed Central

    Xiong, Fuxia; Zhang, Lubo

    2012-01-01

    Adverse environments during the fetal and neonatal development period may permanently program physiology and metabolism, and lead to increased risk of diseases in later life. Programming of the hypothalamic-pituitary-adrenal (HPA) axis is one of the key mechanisms that contribute to altered metabolism and response to stress. Programming of the HPA axis often involves epigenetic modification of the glucocorticoid receptor (GR) gene promoter, which influences tissue-specific GR expression patterns and response to stimuli. This review summarizes the current state of research on the HPA axis and programming of health and disease in the adult, focusing on the epigenetic regulation of GR gene expression patterns in response to fetal and neonatal stress. Aberrant GR gene expression patterns in the developing brain may have a significant negative impact on protection of the immature brain against hypoxic-ischemic encephalopathy in the critical period of development during and immediately after birth. PMID:23200813

  17. Education in Marine Science and Technology--Historical and Current Issues.

    ERIC Educational Resources Information Center

    Abel, Robert B.

    This review of marine science and technology education and related issues was presented to the American Association for the Advancement of Science, December 27, 1967. Areas reviewed include manpower supply and demand, oceanography education history, oceanography and the social sciences, training of technicians, the ocean engineer, education for…

  18. Mazama ash in the Northeastern Pacific

    USGS Publications Warehouse

    Nelson, C.H.; Kulm, L.D.; Carlson, P.R.; Duncan, J.R.

    1968-01-01

    Volcanic glass in marine sediments off Oregon and Washington correlates with continental deposits of Mount Mazama ash by stratigraphic position, refractive index, and radiocarbon dating. Ash deposited in the abyssal regions by turbidity currents is used for tracing of the dispersal routes of postglacial sediments and for evaluation of marine sedimentary processes.

  19. NATIONAL WEATHER SERVICE MARINE PRODUCTS VIA INTERNET

    Science.gov Websites

    ! Boating Safety Beach Hazards Rip Currents Hypothermia Hurricanes Thunderstorms Lightning Coastal Flooding Text Forecasts and Products. For convenience, High Seas, Offshore and Coastal marine forecasts are available via the Internet for most U.S. coastal areas. Gridded forecast data for offshore and high seas

  20. NOAA TELEPHONE RECORDINGS

    Science.gov Websites

    ! Boating Safety Beach Hazards Rip Currents Hypothermia Hurricanes Thunderstorms Lightning Coastal Flooding . Mariners can now hear the latest coastal and offshore weather observations using Dial-A-Buoy. Dial-A-Buoy wind and wave measurements taken within the last hour at 65 buoy and 54 Coastal-Marine Automated

  1. National Weather Service Marine Forecasts - FAQ

    Science.gov Websites

    ! Boating Safety Beach Hazards Rip Currents Hypothermia Hurricanes Thunderstorms Lightning Coastal Flooding marine coastal areas may be found in Appendix B of the National Ocean Service's Coast Pilot's, volumes 1 Advisory (SCA): An advisory issued by coastal and Great Lakes Weather Forecast Offices (WFO) for areas

  2. NATIONAL WEATHER SERVICE MARINE PRODUCTS VIA NOAA WEATHER RADIO

    Science.gov Websites

    ! Boating Safety Beach Hazards Rip Currents Hypothermia Hurricanes Thunderstorms Lightning Coastal Flooding Radio network provides voice broadcasts of local and coastal marine forecasts on a continuous cycle. The forecasts are produced by local National Weather Service Forecast Offices. Coastal stations also broadcast

  3. Marine and Hydrokinetic Data | Geospatial Data Science | NREL

    Science.gov Websites

    . wave energy resource using a 51-month Wavewatch III hindcast database developed by the National Database The U.S. Department of Energy's Marine and Hydrokinetic Technology Database provides information database includes wave, tidal, current, and ocean thermal energy and contains information about energy

  4. Recent updates of marine antimicrobial peptides.

    PubMed

    Semreen, Mohammad H; El-Gamal, Mohammed I; Abdin, Shifaa; Alkhazraji, Hajar; Kamal, Leena; Hammad, Saba; El-Awady, Faten; Waleed, Dima; Kourbaj, Layal

    2018-03-01

    Antimicrobial peptides are group of proteins showing broad-spectrum antimicrobial activity that have been known to be powerful agents against a variety of pathogens. This class of compounds contributed to solving the microbial resistance dilemma that limited the use of many potent antimicrobial agents. The marine environment is known to be one of the richest sources for antimicrobial peptides, yet this environment is not fully explored. Hence, the scientific research attention should be directed toward the marine ecosystem as enormous amount of useful discoveries could be brought to the forefront. In the current article, the marine antimicrobial peptides reported from mid 2012 to 2017 have been reviewed.

  5. Can We "Future-Proof" Marine Conservation Planning?

    NASA Astrophysics Data System (ADS)

    Pinsky, M. L.; Rogers, L. A.

    2016-02-01

    Marine conservation and marine spatial planning strategies worldwide are designed around biogeographic patterns, often under the assumption that these patterns are relatively stable. With climate change, however, distributions are shifting rapidly as species seek more suitable conditions. Here, we use distribution projections from 2006-2100 for 360 marine species in North America to evaluate the effectiveness of the current marine protected area (MPA) network and to test climate-ready planning approaches. We consider both expected community changes and the uncertainty in those projections. We find that existing MPAs are likely to lose more species over the coming century than other locations on the continental shelf. We also find substantial shifts in the location of high- and low-value regions, which can complicate conservation planning. However, planning portfolios can be developed that perform much better in the face of changes expected over the coming century. The theory and practice of marine spatial planning and marine conservation can be substantially more responsive to our dynamic ocean.

  6. The role of sustained observations in tracking impacts of environmental change on marine biodiversity and ecosystems

    PubMed Central

    Mieszkowska, N.; Sugden, H.; Firth, L. B.; Hawkins, S. J.

    2014-01-01

    Marine biodiversity currently faces unprecedented threats from multiple pressures arising from human activities. Global drivers such as climate change and ocean acidification interact with regional eutrophication, exploitation of commercial fish stocks and localized pressures including pollution, coastal development and the extraction of aggregates and fuel, causing alteration and degradation of habitats and communities. Segregating natural from anthropogenically induced change in marine ecosystems requires long-term, sustained observations of marine biota. In this review, we outline the history of biological recording in the coastal and shelf seas of the UK and Ireland and highlight where sustained observations have contributed new understanding of how anthropogenic activities have impacted on marine biodiversity. The contributions of sustained observations, from those collected at observatories, single station platforms and multiple-site programmes to the emergent field of multiple stressor impacts research, are discussed, along with implications for management and sustainable governance of marine resources in an era of unprecedented use of the marine environment. PMID:25157190

  7. Marine-Based Nutraceuticals: An Innovative Trend in the Food and Supplement Industries.

    PubMed

    Suleria, Hafiz Ansar Rasul; Osborne, Simone; Masci, Paul; Gobe, Glenda

    2015-10-14

    Recent trends in functional foods and supplements have demonstrated that bioactive molecules play a major therapeutic role in human disease. Nutritionists and biomedical and food scientists are working together to discover new bioactive molecules that have increased potency and therapeutic benefits. Marine life constitutes almost 80% of the world biota with thousands of bioactive compounds and secondary metabolites derived from marine invertebrates such as tunicates, sponges, molluscs, bryozoans, sea slugs and many other marine organisms. These bioactive molecules and secondary metabolites possess antibiotic, antiparasitic, antiviral, anti-inflammatory, antifibrotic and anticancer activities. They are also inhibitors or activators of critical enzymes and transcription factors, competitors of transporters and sequestrants that modulate various physiological pathways. The current review summaries the widely available marine-based nutraceuticals and recent research carried out for the purposes of isolation, identification and characterization of marine-derived bioactive compounds with various therapeutic potentials.

  8. Marine-Based Nutraceuticals: An Innovative Trend in the Food and Supplement Industries

    PubMed Central

    Suleria, Hafiz Ansar Rasul; Osborne, Simone; Masci, Paul; Gobe, Glenda

    2015-01-01

    Recent trends in functional foods and supplements have demonstrated that bioactive molecules play a major therapeutic role in human disease. Nutritionists and biomedical and food scientists are working together to discover new bioactive molecules that have increased potency and therapeutic benefits. Marine life constitutes almost 80% of the world biota with thousands of bioactive compounds and secondary metabolites derived from marine invertebrates such as tunicates, sponges, molluscs, bryozoans, sea slugs and many other marine organisms. These bioactive molecules and secondary metabolites possess antibiotic, antiparasitic, antiviral, anti-inflammatory, antifibrotic and anticancer activities. They are also inhibitors or activators of critical enzymes and transcription factors, competitors of transporters and sequestrants that modulate various physiological pathways. The current review summaries the widely available marine-based nutraceuticals and recent research carried out for the purposes of isolation, identification and characterization of marine-derived bioactive compounds with various therapeutic potentials. PMID:26473889

  9. Structural diversity of marine cyclic peptides and their molecular mechanisms for anticancer, antibacterial, antifungal, and other clinical applications.

    PubMed

    Lee, Yeji; Phat, Chanvorleak; Hong, Soon-Cheol

    2017-09-01

    Many cyclic peptides and analogues derived from marine sources are known to possess biological properties, including anticancer, antitumor, antibacterial, antifungal, antiparasitic, anti-inflammation, anti-proliferative, anti-hypertensive, cytotoxic, and antibiotic properties. These compounds demonstrate different activities and modes of action according to their structure such as cyclic oligopeptide, cyclic lipopeptide, cyclic glycopeptide and cyclic depsipeptide. The recent advances in application of the above-mentioned cyclic peptides were reported in dolastatins, soblidotin, didemnin B, aplidine, salinosporamide A, kahalalide F and bryostatin 1 and they are currently in clinical trials. These cyclic peptides are possible novel drugs discovered and developed from marine origin. Literature data concerning the potential properties of marine cyclic peptides were reviewed here, and the structural diversity and biological activities of marine cyclic peptides are discussed in relation to the molecular mechanisms of these marine cyclic peptides. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Template-based synthesis and magnetic properties of Mn-Zn ferrite nanotube and nanowire arrays

    NASA Astrophysics Data System (ADS)

    Guo, Limin; Wang, Xiaohui; Zhong, Caifu; Li, Longtu

    2012-01-01

    Template-based electrophoretic deposition of Mn-Zn ferrite nanotubes (NTs) and nanowires (NWs) were achieved using anodic alumina oxide (AAO) membranes. The effect of electrophoretic current and deposition time on the morphology of the tubes was investigated. The samples show cubic spinel structure with no preferred orientation. Room-temperature magnetic properties of the Mn-Zn ferrite NT/NW arrays were studied. The magnetic easy axis parallels the NT/NW's channel axis attributing to the large shape anisotropy in this direction, especially for the NTs with a small wall thickness. Magnetocrystalline anisotropy and magnetostatic interactions were found dominant in the samples when applied field was perpendicular to the channel axis.

  11. The Spatial and Temporal Distribution of SST in the Yellow Sea and the Evolution of the Yellow Sea Warm Current During the Holocene

    NASA Astrophysics Data System (ADS)

    Jia, Y.; Xiao, X.; Yu, M.; Yuan, Z. N.; Zhang, H.; Zhao, M.

    2017-12-01

    The Yellow Sea (YS) environment is influenced by both continental and oceanic forcing. The Yellow Sea Warm Current (YSWC) is the most significantly hydrological characteristics of the YS in winter, which is a conduit by which the deep Pacific Ocean influences the YS. Paleo-environmental records are essential for understanding the evolution of the YS environment, especially the spatial distribution of the sea surface temperature (SST) records which can be used to interpret the controlling factors of the YSWC. Previous studies mostly focused on the temporal variation but studies on both temporal and spatial environmental evolution are rather sparse. We used Uk37 temperature records in 9 cores located the north of 35°N in YS to reconstruct the spatial/temporal variations of the SST during the Holocene and further to understand the main natural factors that influenced the evolution of the YS environment and current system. All the SST records in 9 sediment cores displayed the similar trend during the Holocene, showing a regional response to marine environmental variability in the east China Seas influenced by the YSWC. To reconstruct the historical westward shift of the YSWC relative to the bathymetric trough of the YS, we compared SST records of the cores located in the west and east side of the axis of the modern YSWC. The obvious westward shift of the YSWC was observed during the periods of 4500-5000aBP, 2800-3400aBP and 1600-0aBP, especially 1000-0aBP, indicating by the distinctly gradual temperature gradients. The comparison of the East Asian Winter Monsoon(EAWM) and the Kuroshio current intensity records with the SST records revealed that the westward shift of the YSWC might be controlled by the Kuroshio intensity. Our findings have important implications for understanding the mechanisms of the variability of the YSWC.

  12. Prepositioned Stocks: Marine Corps Needs to Improve Cost Estimate Reliability and Oversight of Inventory Systems for Equipment in Norway

    DTIC Science & Technology

    2015-09-01

    HMMWV), M1A1 Main Battle Tanks, Tank Retrievers, Armored Breeching Vehicles, Amphibious Assault Vehicles, and several variants of the Medium...MCPP-N equipment stored in the Norwegian caves. As noted earlier, Marine Corps equipment is distributed among six caves. While the current version of...according to Marine Corps Business System Integration Team officials, the initial plan was for the first version of the Global Combat Support System

  13. Management Plan Report. Unconfined Open-Water Disposal of Dredged Material. Phase 2. (North and South Puget Sound)

    DTIC Science & Technology

    1989-09-01

    depth of 442’ at the center of the disposal zone. The area is subject to weak currents. In general, commercially important marine invertebrate ...Fish and Wildlife Service " Charles Dunn U.S. Fish and Wildlife Service * Rob Jones National Marine Fisheries Service * Dr. Herb Curl National Oceanic...environmental impacts. In the future, for many projects, disposal in deep and relatively deep marine waters is expected to be a preferred option for envirc

  14. Use of Electronic Tag Data and Associated Analytical Tools to Identify and Predict Habitat Utilization of Marine Predators

    DTIC Science & Technology

    2013-09-30

    fin, sperm and humpback whales). RESULTS The tracking data reveal that the California Current Large Marine Ecosystem (CCLME; Supplementary...within 1u31u grid cells. b, Density of large marine predators within the CCLME at a 0.25 º 30.25º resolution. The CCLME is a highly retentive area...sooty shearwaters). The retention with and attraction to the CCLME is consistent with the high productivity of this region that supports large

  15. Field trial of a diagnostic axis for defense mechanisms for DSM-IV.

    PubMed

    Perry, J C; Hoglend, P; Shear, K; Vaillant, G E; Horowitz, M; Kardos, M E; Bille, H; Kagan, D

    1998-01-01

    Following critiques that the DSM multiaxial system lacks psychodynamic information useful for treatment, an axis for defense mechanisms was developed for DSM-IV, including up to 7 individual defenses from a glossary of 27, and 3 predominant defense levels from a list of 7. We tested the feasibility, reliability, and discriminability of the proposed axis. Clinician and psychiatric resident volunteers were trained at two U.S. and one Norwegian sites. After conducting initial interviews on 107 patients, they rated the DSM-III-R and defense axes, as did a second blind rater. Median kappa reliabilities were .42 (individual defenses), and .47 (defense levels). A summary measure, Overall Defensive Functioning (ODF), had similar reliability to current GAF (IR .68 vs. .62), similar 1-month stability (.75 vs. .78), but greater 6-month stability (.51 vs. .17). Independent of Axis III, ODF had small to moderate associations with other Axes and symptoms. Our findings indicate that the defense axis is a feasible, acceptably reliable, and nonredundant addition to DSM-IV, which may prove useful for planning and conducting treatment.

  16. Development and calibration of an air-floating six-axis force measurement platform using self-calibration

    NASA Astrophysics Data System (ADS)

    Huang, Bin; Wang, Xiaomeng; Li, Chengwei; Yi, Jiajing; Lu, Rongsheng; Tao, Jiayue

    2016-09-01

    This paper describes the design, working principle, as well as calibration of an air-floating six-axis force measurement platform, where the floating plate and nozzles were connected without contact, preventing inter-dimensional coupling and increasing precision significantly. The measurement repeatability error of the force size in the platform is less than 0.2% full scale (FS), which is significantly better than the precision of 1% FS in the six-axis force sensors on the current market. We overcame the difficulties of weight loading device in high-precision calibration by proposing a self-calibration method based on the floating plate gravity and met the calibration precision requirement of 0.02% FS. This study has general implications for the development and calibration of high-precision multi-axis force sensors. In particular, the air-floating six-axis force measurement platform could be applied to the calibration of some special sensors such as flexible tactile sensors and may be used as a micro-nano mechanical assembly platform for real-time assembly force testing.

  17. Cytokines and neuro-immune-endocrine interactions: a role for the hypothalamic-pituitary-adrenal revolving axis.

    PubMed

    Haddad, John J; Saadé, Nayef E; Safieh-Garabedian, Bared

    2002-12-01

    Cytokines, peptide hormones and neurotransmitters, as well as their receptors/ligands, are endogenous to the brain, endocrine and immune systems. These shared ligands and receptors are used as a common chemical language for communication within and between the immune and neuroendocrine systems. Such communication suggests an immunoregulatory role for the brain and a sensory function for the immune system. Interplay between the immune, nervous and endocrine systems is most commonly associated with the pronounced effects of stress on immunity. The hypothalamic-pituitary-adrenal (HPA) axis is the key player in stress responses; it is well established that both external and internal stressors activate the HPA axis. Cytokines are chemical messengers that stimulate the HPA axis when the body is under stress or experiencing an infection. This review discusses current knowledge of cytokine signaling pathways in neuro-immune-endocrine interactions as viewed through the triplet HPA axis. In addition, we elaborate on HPA/cytokine interactions in oxidative stress within the context of nuclear factor-kappaB transcriptional regulation and the role of oxidative markers and related gaseous transmitters.

  18. Phytochemicals for taming agitated immune-endocrine-neural axis.

    PubMed

    Patel, Seema

    2017-07-01

    Homeostasis of immune-endocrine-neural axis is paramount for human health. If this axis gets agitated due to age, genetic variations, environmental exposures or lifestyle assaults, a cascade of adverse reactions occurs in human body. Cytokines, hormones and neurotransmitters, the effector molecules of this axis behave erratically, leading to a gamut of neural, endocrine, autoimmune, and metabolic diseases. Current panel of drugs can tackle some of them but not in a sustainable, benign way as a myriad of side effects, causal of them have been documented. In this context, phytochemicals, the secondary metabolites of plants seem beneficial. These bioactive constituents encompassing polyphenols, alkaloids, flavonoids, terpenoids, tannins, lignans, stilbenoids (resveratrol), saponins, polysaccharides, glycosides, and lectins etc. have been proven to exert antioxidant, anti-inflammatory, hypolipidemic, hypotensive, antidiabetic, anticancer, immunomodulatory, anti-allergic, analgesic, hepatoprotective, neuroprotective, dermatoprotective, and antimicrobial properties, among a litany of other biological effects. This review presents a holistic perspective of common afflictions resultant of immune-endocrine-neural axis disruption, and the phytochemicals capable of restoring their normalcy and mitigating the ailments. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  19. Marine Pharmacology in 2000: Marine Compounds with Antibacterial, Anticoagulant, Antifungal, Anti-inflammatory, Antimalarial, Antiplatelet, Antituberculosis, and Antiviral Activities; Affecting the Cardiovascular, Immune, and Nervous Systems and Other Miscellaneous Mechanisms of Action

    PubMed Central

    Mayer, Alejandro M. S.; Hamann, Mark T.

    2016-01-01

    During 2000 research on the pharmacology of marine chemicals involved investigators from Australia, Brazil, Canada, Egypt, France, Germany, India, Indonesia, Israel, Italy, Japan, the Netherlands, New Zealand, Phillipines, Singapore, Slovenia, South Korea, Spain, Sweden, Switzerland, United Kingdom, and the United States. This current review, a sequel to the authors’ 1998 and 1999 reviews, classifies 68 peer-reviewed articles on the basis of the reported preclinical pharmacologic properties of marine chemicals derived from a diverse group of marine animals, algae, fungi, and bacteria. Antibacterial, anticoagulant, antifungal, antimalarial, antiplatelet, antituberculosis, or antiviral activity was reported for 35 marine chemicals. An additional 20 marine compounds were shown to have significant effects on the cardiovascular and nervous system, and to possess anti-inflammatory or immunosuppressant properties. Finally, 23 marine compounds were reported to act on a variety of molecular targets and thus could potentially contribute to several pharmacologic classes. Thus, as in 1998 and 1999, during 2000 pharmacologic research with marine chemicals continued to contribute potentially novel chemical leads to the ongoing global search for therapeutic agents in the treatment of multiple disease categories. PMID:14583811

  20. Marine pharmacology in 2003-4: marine compounds with anthelmintic antibacterial, anticoagulant, antifungal, anti-inflammatory, antimalarial, antiplatelet, antiprotozoal, antituberculosis, and antiviral activities; affecting the cardiovascular, immune and nervous systems, and other miscellaneous mechanisms of action.

    PubMed

    Mayer, Alejandro M S; Rodríguez, Abimael D; Berlinck, Roberto G S; Hamann, Mark T

    2007-05-01

    The current marine pharmacology review that covers the peer-reviewed literature during 2003 and 2004 is a sequel to the authors' 1998-2002 reviews, and highlights the preclinical pharmacology of 166 marine chemicals derived from a diverse group of marine animals, algae, fungi and bacteria. Anthelmintic, antibacterial, anticoagulant, antifungal, antimalarial, antiplatelet, antiprotozoal, antituberculosis or antiviral activities were reported for 67 marine chemicals. Additionally 45 marine compounds were shown to have significant effects on the cardiovascular, immune and nervous system as well as possessing anti-inflammatory effects. Finally, 54 marine compounds were reported to act on a variety of molecular targets and thus may potentially contribute to several pharmacological classes. Thus, during 2003-2004, research on the pharmacology of marine natural products which involved investigators from Argentina, Australia, Brazil, Belgium, Canada, China, France, Germany, India, Indonesia, Israel, Italy, Japan, Mexico, Morocco, the Netherlands, New Zealand, Norway, Panama, the Philippines, Portugal, Russia, Slovenia, South Korea, Spain, Thailand, Turkey, United Kingdom, and the United States, contributed numerous chemical leads for the continued global search for novel therapeutic agents with broad spectrum activity.

  1. Marine pharmacology in 2003-4: Marine Compounds with Anthelminthic, Antibacterial, Anticoagulant, Antifungal, Anti-inflammatory, Antimalarial, Antiplatelet, Antiprotozoal, Antituberculosis, and Antiviral Activities; affecting the Cardiovascular, Immune and Nervous Systems, and other Miscellaneous Mechanisms of Action

    PubMed Central

    Mayer, Alejandro M.S.; Rodriguez, Abimael D.; Berlinck, Roberto G.S.; Hamann, Mark T.

    2007-01-01

    The current marine pharmacology review that covers the peer-reviewed literature during 2003 and 2004 is a sequel to the authors' 1998-2002 reviews, and highlights the preclinical pharmacology of 166 marine chemicals derived from a diverse group of marine animals, algae, fungi and bacteria. Anthelminthic, antibacterial, anticoagulant, antifungal, antimalarial, antiplatelet, antiprotozoal, antituberculosis or antiviral activities were reported for 67 marine chemicals. Additionally 45 marine compounds were shown to have significant effects on the cardiovascular, immune and nervous system as well as possessing anti-inflammatory effects. Finally, 54 marine compounds were reported to act on a variety of molecular targets and thus may potentially contribute to several pharmacological classes. Thus, during 2003-2004, research on the pharmacology of marine natural products which involved investigators from Argentina, Australia, Brazil, Belgium, Canada, China, France, Germany, India, Indonesia, Israel, Italy, Japan, Mexico, Morocco, the Netherlands, New Zealand, Norway, Panama, the Philippines, Portugal, Russia, Slovenia, South Korea, Spain, Thailand, Turkey, United Kingdom, and the United States, contributed numerous chemical leads for the continued global search for novel therapeutic agents with broad spectrum activity. PMID:17392033

  2. Omics of the marine medaka (Oryzias melastigma) and its relevance to marine environmental research.

    PubMed

    Kim, Bo-Mi; Kim, Jaebum; Choi, Ik-Young; Raisuddin, Sheikh; Au, Doris W T; Leung, Kenneth M Y; Wu, Rudolf S S; Rhee, Jae-Sung; Lee, Jae-Seong

    2016-02-01

    In recent years, the marine medaka (Oryzias melastigma), also known as the Indian medaka or brackish medaka, has been recognized as a model fish species for ecotoxicology and environmental research in the Asian region. O. melastigma has several promising features for research, which include a short generation period (3-4 months), daily spawning, small size (3-4 cm), transparent embryos, sexual dimorphism, and ease of mass culture in the laboratory. There have been extensive transcriptome and genome studies on the marine medaka in the past decade. Such omics data can be useful in understanding the signal transduction pathways of small teleosts in response to environmental stressors. An omics-integrated approach in the study of the marine medaka is important for strengthening its role as a small fish model for marine environmental studies. In this review, we present current omics information about the marine medaka and discuss its potential applications in the study of various molecular pathways that can be targets of marine environmental stressors, such as chemical pollutants. We believe that this review will encourage the use of this small fish as a model species in marine environmental research. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. New perspectives on sea use management: initial findings from European experience with marine spatial planning.

    PubMed

    Douvere, Fanny; Ehler, Charles N

    2009-01-01

    Increased development pressures on the marine environment and the potential for multiple use conflicts, arising as a result of the current expansion of offshore wind energy, fishing and aquaculture, dredging, mineral extraction, shipping, and the need to meet international and national commitments to biodiversity conservation, have led to increased interest in sea use planning with particular emphasis on marine spatial planning. Several European countries, on their own initiative or driven by the European Union's Marine Strategy and Maritime Policy, the Bergen Declaration of the North Sea Conference, and the EU Recommendation on Integrated Coastal Zone Management, have taken global leadership in implementing marine spatial planning. Belgium, The Netherlands, and Germany in the North Sea, and the United Kingdom in the Irish Sea, have already completed preliminary sea use plans and zoning proposals for marine areas within their national jurisdictions. This paper discusses the nature and context of marine spatial planning, the international legal and policy framework, and the increasing need for marine spatial planning in Europe. In addition, the authors review briefly three marine spatial planning initiatives in the North Sea and conclude with some initial lessons learned from these experiences.

  4. Biosurfactant-induced remediation of contaminated marine sediments: Current knowledge and future perspectives.

    PubMed

    Dell'Anno, F; Sansone, C; Ianora, A; Dell'Anno, A

    2018-06-01

    The contamination of marine sediments is widespread in coastal regions of the world and represents a major concern for the potential detrimental consequences on ecosystems' health and provision of goods and services for human wellbeing. Thus, there is an urgent need to find sustainable and eco-compatible solutions for the remediation of contaminated sediments. Bioremediation is a low cost and environmental-friendly strategy with a high potential for the remediation of contaminated marine sediments. Here we review the potential application of biosurfactants produced by microbial taxa for the remediation of contaminated marine sediments and we discuss future research needs to develop efficient and eco-sustainable biosurfactant-based strategies for the recovery of contaminated marine sediments, in view of large-scale applications. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Marine Polysaccharides in Pharmaceutical Applications: An Overview

    PubMed Central

    Laurienzo, Paola

    2010-01-01

    The enormous variety of polysaccharides that can be extracted from marine plants and animal organisms or produced by marine bacteria means that the field of marine polysaccharides is constantly evolving. Recent advances in biological techniques allow high levels of polysaccharides of interest to be produced in vitro. Biotechnology is a powerful tool to obtain polysaccharides from a variety of micro-organisms, by controlling the growth conditions in a bioreactor while tailoring the production of biologically active compounds. Following an overview of the current knowledge on marine polysaccharides, with special attention to potential pharmaceutical applications and to more recent progress on the discovering of new polysaccharides with biological appealing characteristics, this review will focus on possible strategies for chemical or physical modification aimed to tailor the final properties of interest. PMID:20948899

  6. Combining Classical and Molecular Approaches Elaborates on the Complexity of Mechanisms Underpinning Anterior Regeneration

    PubMed Central

    Evans, Deborah J.; Owlarn, Suthira; Tejada Romero, Belen; Chen, Chen; Aboobaker, A. Aziz

    2011-01-01

    The current model of planarian anterior regeneration evokes the establishment of low levels of Wnt signalling at anterior wounds, promoting anterior polarity and subsequent elaboration of anterior fate through the action of the TALE class homeodomain PREP. The classical observation that decapitations positioned anteriorly will regenerate heads more rapidly than posteriorly positioned decapitations was among the first to lead to the proposal of gradients along an anteroposterior (AP) axis in a developmental context. An explicit understanding of this phenomenon is not included in the current model of anterior regeneration. This raises the question what the underlying molecular and cellular basis of this temporal gradient is, whether it can be explained by current models and whether understanding the gradient will shed light on regenerative events. Differences in anterior regeneration rate are established very early after amputation and this gradient is dependent on the activity of Hedgehog (Hh) signalling. Animals induced to produce two tails by either Smed-APC-1(RNAi) or Smed-ptc(RNAi) lose anterior fate but form previously described ectopic anterior brain structures. Later these animals form peri-pharyngeal brain structures, which in Smed-ptc(RNAi) grow out of the body establishing a new A/P axis. Combining double amputation and hydroxyurea treatment with RNAi experiments indicates that early ectopic brain structures are formed by uncommitted stem cells that have progressed through S-phase of the cell cycle at the time of amputation. Our results elaborate on the current simplistic model of both AP axis and brain regeneration. We find evidence of a gradient of hedgehog signalling that promotes posterior fate and temporarily inhibits anterior regeneration. Our data supports a model for anterior brain regeneration with distinct early and later phases of regeneration. Together these insights start to delineate the interplay between discrete existing, new, and then later homeostatic signals in AP axis regeneration. PMID:22125640

  7. Combining classical and molecular approaches elaborates on the complexity of mechanisms underpinning anterior regeneration.

    PubMed

    Evans, Deborah J; Owlarn, Suthira; Tejada Romero, Belen; Chen, Chen; Aboobaker, A Aziz

    2011-01-01

    The current model of planarian anterior regeneration evokes the establishment of low levels of Wnt signalling at anterior wounds, promoting anterior polarity and subsequent elaboration of anterior fate through the action of the TALE class homeodomain PREP. The classical observation that decapitations positioned anteriorly will regenerate heads more rapidly than posteriorly positioned decapitations was among the first to lead to the proposal of gradients along an anteroposterior (AP) axis in a developmental context. An explicit understanding of this phenomenon is not included in the current model of anterior regeneration. This raises the question what the underlying molecular and cellular basis of this temporal gradient is, whether it can be explained by current models and whether understanding the gradient will shed light on regenerative events. Differences in anterior regeneration rate are established very early after amputation and this gradient is dependent on the activity of Hedgehog (Hh) signalling. Animals induced to produce two tails by either Smed-APC-1(RNAi) or Smed-ptc(RNAi) lose anterior fate but form previously described ectopic anterior brain structures. Later these animals form peri-pharyngeal brain structures, which in Smed-ptc(RNAi) grow out of the body establishing a new A/P axis. Combining double amputation and hydroxyurea treatment with RNAi experiments indicates that early ectopic brain structures are formed by uncommitted stem cells that have progressed through S-phase of the cell cycle at the time of amputation. Our results elaborate on the current simplistic model of both AP axis and brain regeneration. We find evidence of a gradient of hedgehog signalling that promotes posterior fate and temporarily inhibits anterior regeneration. Our data supports a model for anterior brain regeneration with distinct early and later phases of regeneration. Together these insights start to delineate the interplay between discrete existing, new, and then later homeostatic signals in AP axis regeneration.

  8. The Framework for an Information Technology Strategic Roadmap for the United States Marine Corps: How Current Acquisitions Align to the Current Strategic Direction of the Department of Defense, Department of the Navy, and United States Marine Corps

    DTIC Science & Technology

    2008-06-01

    PAGE INTENTIONALLY LEFT BLANK xv ACKNOWLEDGMENTS We would like to thank Mr. Clint Swett (Director, Technology Services Organization, DFAS- KC ) and...Major Jeffrey Thiry (Deputy Director, Technology Services Organization, DFAS- KC ) for their help and support. Their guidance proved invaluable in... Teo (1996) define alignment as the “coordination between the business and IS planning functions and activities”. Luftman, Papp and Brier (1999

  9. The influence of anode position and structure on cusped field thruster

    NASA Astrophysics Data System (ADS)

    Niu, Xiang; Liu, Hui; Yang, Chiyu; Jiang, Wenjia; Yu, Daren; Ning, Zhongxi

    2018-04-01

    A cusped field thruster is a kind of electric propulsion device using multi-stage cusped fields to realize plasma discharges and produce thrust. A previous study showed that plasma discharges in this thruster are non-uniform. In this work, a multi-annulus anode is used to measure the radial distribution of anode current density at different anode positions. The experimental results reveal that some electrons may reach the anode along the axis after they accelerate from the final cusp regardless of the anode positions. To further validate this idea and find out the mechanism of this central path along the axis, the central part of the anode is replaced with ceramics. This results in an increase in the total current with larger contributions at larger radii. The current oscillations also get larger. This brief letter is helpful to further understand the movement of electrons in cusped field thrusters and provide guidance on reducing the non-uniform degree of current density.

  10. Electron Cyclotron Current Drive Efficiency in General Tokamak Geometry and Its Application to Advanced Tokamak Plasmas

    NASA Astrophysics Data System (ADS)

    Lin-Liu, Y. R.; Chan, V. S.; Luce, T. C.; Prater, R.

    1998-11-01

    Owing to relativistic mass shift in the cyclotron resonance condition, a simple and accurate interpolation formula for estimating the current drive efficiency, such as those(S.C. Chiu et al.), Nucl. Fusion 29, 2175 (1989).^,(D.A. Ehst and C.F.F. Karney, Nucl. Fusion 31), 1933 (1991). commonly used in FWCD, is not available in the case of ECCD. In this work, we model ECCD using the adjoint techniques. A semi-analytic adjoint function appropriate for general tokamak geometry is obtained using Fisch's relativistic collision model. Predictions of off-axis ECCD qualitatively and semi-quantitatively agrees with those of Cohen,(R.H. Cohen, Phys. Fluids 30), 2442 (1987). currently implemented in the raytracing code TORAY. The dependences of the current drive efficiency on the wave launch configuration and the plasma parameters will be presented. Strong absorption of the wave away from the resonance layer is shown to be an important factor in optimizing the off-axis ECCD for application to advanced tokamak operations.

  11. Current Status and Future Prospects of Marine Natural Products (MNPs) as Antimicrobials

    PubMed Central

    Choudhary, Alka; Naughton, Lynn M.; Montánchez, Itxaso

    2017-01-01

    The marine environment is a rich source of chemically diverse, biologically active natural products, and serves as an invaluable resource in the ongoing search for novel antimicrobial compounds. Recent advances in extraction and isolation techniques, and in state-of-the-art technologies involved in organic synthesis and chemical structure elucidation, have accelerated the numbers of antimicrobial molecules originating from the ocean moving into clinical trials. The chemical diversity associated with these marine-derived molecules is immense, varying from simple linear peptides and fatty acids to complex alkaloids, terpenes and polyketides, etc. Such an array of structurally distinct molecules performs functionally diverse biological activities against many pathogenic bacteria and fungi, making marine-derived natural products valuable commodities, particularly in the current age of antimicrobial resistance. In this review, we have highlighted several marine-derived natural products (and their synthetic derivatives), which have gained recognition as effective antimicrobial agents over the past five years (2012–2017). These natural products have been categorized based on their chemical structures and the structure-activity mediated relationships of some of these bioactive molecules have been discussed. Finally, we have provided an insight into how genome mining efforts are likely to expedite the discovery of novel antimicrobial compounds. PMID:28846659

  12. Participatory Sensing Marine Debris: Current Trends and Future Opportunities

    NASA Astrophysics Data System (ADS)

    Jambeck, J.; Johnsen, K.

    2016-02-01

    The monitoring of litter and debris is challenging at the global scale because of spatial and temporal variability, disconnected local organizations and the use of paper and pen for documentation. The Marine Debris Tracker mobile app and citizen science program allows for the collection of global standardized data at a scale, speed and efficiency that was not previously possible. The app itself also serves as an outreach and education tool, creating an engaged participatory sensing instrument. This instrument is characterized by several aspects including range and frequency, accuracy and precision, accessibility, measurement dimensions, participant performance, and statistical analysis. Also, important to Marine Debris Tracker is open data and transparency. A web portal provides data that users have logged allowing immediate feedback to users and additional education opportunities. The engagement of users through a top tracker competition and social media keeps participants interested in the Marine Debris Tracker community. Over half a million items have been tracked globally, and maps provide both global and local distribution of data. The Marine Debris Tracker community and dataset continues to grow daily. We will present current usage and engagement, participatory sensing data distributions, choropleth maps of areas of active tracking, and discuss future technologies and platforms to expand data collection and conduct statistical analysis.

  13. Climate change. Six centuries of variability and extremes in a coupled marine-terrestrial ecosystem.

    PubMed

    Black, Bryan A; Sydeman, William J; Frank, David C; Griffin, Daniel; Stahle, David W; García-Reyes, Marisol; Rykaczewski, Ryan R; Bograd, Steven J; Peterson, William T

    2014-09-19

    Reported trends in the mean and variability of coastal upwelling in eastern boundary currents have raised concerns about the future of these highly productive and biodiverse marine ecosystems. However, the instrumental records on which these estimates are based are insufficiently long to determine whether such trends exceed preindustrial limits. In the California Current, a 576-year reconstruction of climate variables associated with winter upwelling indicates that variability increased over the latter 20th century to levels equaled only twice during the past 600 years. This modern trend in variance may be unique, because it appears to be driven by an unprecedented succession of extreme, downwelling-favorable, winter climate conditions that profoundly reduce productivity for marine predators of commercial and conservation interest. Copyright © 2014, American Association for the Advancement of Science.

  14. Developing a Knowledge Management Framework to Assist With Current USMC Information Management Practices

    DTIC Science & Technology

    2010-09-01

    OF CONTENTS I. INTRODUCTION ........................................................................................................1 II. LITERATURE...LEFT BLANK 1 I. INTRODUCTION Marine Corps Information Management is performed in accordance with Marine Corps Warfighting Publication (MCWP) 3...November 13). Air Force Center of Excellence for Knowledge Mangement Briefing. Washington, D.C. Alavi, M., & Leidner, D. E. (2001). Review: Knowledge

  15. Toward an Improved U.S. Merchant Marine: A Recommended Program of Studies.

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC.

    This report describes the development and current status of the U.S. Merchant Marine with special emphasis on the influences of government, management, labor, and users. The report describes a wide spectrum of maritime activities, including the roles of various government agencies, the organization and effectiveness of U.S. Merchant Marine…

  16. 78 FR 25703 - Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Fisheries Research

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-02

    ... research surveys in the California Current Research Area (off the U.S. west coast), the Eastern Tropical...-independent research onboard NOAA-owned and operated vessels or on chartered vessels. A few surveys are... surveys also use active acoustic devices. A more detailed description of the fisheries research conducted...

  17. The Gellyfish: an in-situ equilibrium-based sampler for determining multiple free metal ion concentrations in marine ecosystems

    EPA Science Inventory

    Free metal ions are usually the most bioavailable and toxic metal species to aquatic organisms, but they are difficult to measure because of their extremely low concentrations in the marine environment. Many of the current methods for determining free metal ions are complicated a...

  18. The Rorschach: projective technique or psychometric test?

    PubMed

    Aronow, E; Reznikoff, M; Moreland, K L

    1995-04-01

    Various approaches to the Rorschach Technique are described in terms of the idiographic-nomothetic axis and the perceptual-content axis. It is suggested that it is most productive to view the Rorschach as a projective tool, with perceptual scoring a secondary factor. Current efforts at objectification of the Rorschach are not seen as useful as efforts to enhance its projective qualities. Some possible ways are discussed in which the projective value of the instrument can be maximized.

  19. Fast steering and quick positioning of large field-of-regard, two-axis, four-gimbaled sight

    NASA Astrophysics Data System (ADS)

    Ansari, Zahir Ahmed; Nigam, Madhav Ji; Kumar, Avnish

    2017-07-01

    Fast steering and quick positioning are prime requirements of the current electro-optical tracking system to achieve quick target acquisition. A scheme has been proposed for realizing these features using two-axis, four-gimbaled sight. For steering the line of sight in the stabilization mode, outer gimbal is slaved to the gyro stabilized inner gimbal. Typically, the inner gimbals have direct drives and outer gimbals have geared drives, which result in a mismatch in the acceleration capability of their servo loops. This limits the allowable control bandwidth for the inner gimbal. However, to achieve high stabilization accuracy, high bandwidth control loops are essential. This contradictory requirement has been addressed by designing a suitable command conditioning module for the inner gimbals. Also, large line-of-sight freedom in pitch axis is required to provide a wide area surveillance capacity for airborne application. This leads to a loss of freedom along the yaw axis as the pitch angle goes beyond 70 deg or so. This is addressed by making the outer gimbal master after certain pitch angle. Moreover, a mounting scheme for gyro has been proposed to accomplish yaw axis stabilization for 110-deg pitch angle movement with a single two-axis gyro.

  20. A Wavelet Bicoherence-Based Quadratic Nonlinearity Feature for Translational Axis Condition Monitoring

    PubMed Central

    Li, Yong; Wang, Xiufeng; Lin, Jing; Shi, Shengyu

    2014-01-01

    The translational axis is one of the most important subsystems in modern machine tools, as its degradation may result in the loss of the product qualification and lower the control precision. Condition-based maintenance (CBM) has been considered as one of the advanced maintenance schemes to achieve effective, reliable and cost-effective operation of machine systems, however, current vibration-based maintenance schemes cannot be employed directly in the translational axis system, due to its complex structure and the inefficiency of commonly used condition monitoring features. In this paper, a wavelet bicoherence-based quadratic nonlinearity feature is proposed for translational axis condition monitoring by using the torque signature of the drive servomotor. Firstly, the quadratic nonlinearity of the servomotor torque signature is discussed, and then, a biphase randomization wavelet bicoherence is introduced for its quadratic nonlinear detection. On this basis, a quadratic nonlinearity feature is proposed for condition monitoring of the translational axis. The properties of the proposed quadratic nonlinearity feature are investigated by simulations. Subsequently, this feature is applied to the real-world servomotor torque data collected from the X-axis on a high precision vertical machining centre. All the results show that the performance of the proposed feature is much better than that of original condition monitoring features. PMID:24473281

  1. Perioperative corticosteroid management for patients with inflammatory bowel disease.

    PubMed

    Hicks, Caitlin W; Wick, Elizabeth C; Salvatori, Roberto; Ha, Christina Y

    2015-01-01

    Guidelines on the appropriate use of perioperative steroids in patients with inflammatory bowel disease (IBD) are lacking. As a result, corticosteroid supplementation during and after colorectal surgery procedures has been shown to be highly variable. A clearer understanding of the indications for perioperative corticosteroid administration relative to preoperative corticosteroid dosing and duration of therapy is essential. In this review, we outline the basic tenets of the hypothalamic-pituitary-adrenal (HPA) axis and its normal response to stress, describe how corticosteroid use is thought to affect this system, and provide an overview of the currently available data on perioperative corticosteroid supplementation including the limited evidence pertaining to patients with inflammatory bowel disease. Based on currently existing data, we define "adrenal suppression," and propose a patient-based approach to perioperative corticosteroid management in the inflammatory bowel disease population based on an individual's historical use of corticosteroids, the type of surgery they are undergoing, and HPA axis testing when applicable. Patients without adrenal suppression (<5 mg prednisone per day) do not require extra corticosteroid supplementation in the perioperative period; patients with adrenal suppression (>20 mg prednisone per day) should be treated with additional perioperative corticosteroid coverage above their baseline home regimen; and patients with unclear HPA axis function (>5 and <20 mg prednisone per day) should undergo preoperative HPA axis testing to determine the best management practices. The proposed management algorithm attempts to balance the risks of adrenal insufficiency and immunosuppression.

  2. Scope of wind energy in Bangladesh and simulation analysis of three different horizontal axis wind turbine blade shapes

    NASA Astrophysics Data System (ADS)

    Khan, Md. Arif-Ul Islam; Das, Swapnil; Dey, Saikat

    2017-12-01

    : Economic growth and energy demand are intertwined. Therefore, one of the most important concerns of the government and in the world is the need for energy security. Currently, the world relies on coal, crude oil and natural gas for energy generati on. However, the energy crisis together with climate change and depletion of oil have become major concerns to all countries. Therefore, alternative energy resources such as wind energy attracted interest from both public and private sectors to invest in energy generation from this source extensively. Both Vertical and Horizontal axis wind turbine can be used for this purpose. But, Horizontal axis is the most promising between them due to its efficiency and low expense. Bangladesh being a tropical country does have a lot of wind flow at different seasons of the year. However, there are some windy locations in which wind energy projects could be feasible. In this project a detailed review of the current st ate-of-art for wind turbine blade design is presented including theoretical maximum efficiency, Horizontal Axis Wind Turbine (HAWT) blade design, simulation power and COP values for different blade material. By studying previously collected data on the wind resources available in B angladesh at present and by analyzing this data, this paper will discuss the scope of wind energy in Bangladesh.

  3. 2000W high beam quality diode laser for direct materials processing

    NASA Astrophysics Data System (ADS)

    Qin, Wen-bin; Liu, You-qiang; Cao, Yin-hua; Gao, Jing; Pan, Fei; Wang, Zhi-yong

    2011-11-01

    This article describes high beam quality and kilowatt-class diode laser system for direct materials processing, using optical design software ZEMAX® to simulate the diode laser optical path, including the beam shaping, collimation, coupling, focus, etc.. In the experiment, the diode laser stack of 808nm and the diode laser stack of 915nm were used for the wavelength coupling, which were built vertical stacks up to 16 bars. The threshold current of the stack is 6.4A, the operating current is 85A and the output power is 1280W. Through experiments, after collimating the diode laser beam with micro-lenses, the fast axis BPP of the stack is less than 60mm.mrad, and the slow-axis BPP of the stack is less than 75mm.mrad. After shaping the laser beam and improving the beam quality, the fast axis BPP of the stack is still 60mm.mrad, and the slow-axis BPP of the stack is less than 19mm.mrad. After wavelength coupling and focusing, ultimately the power of 2150W was obtained, focal spot size of 1.5mm * 1.2mm with focal length 300mm. The laser power density is 1.2×105W/cm2, and that can be used for metal remelting, alloying, cladding and welding. The total optical coupling conversion efficiency is 84%, and the total electrical - optical conversion efficiency is 50%.

  4. Destabilization of counter-propagating TAEs by off-axis, co-current Neutral Beam Injection

    NASA Astrophysics Data System (ADS)

    Podesta', M.; Fredrickson, E.; Gorelenkova, M.

    2017-10-01

    Neutral Beam injection (NBI) is a common tool to heat the plasma and drive current non-inductively in fusion devices. Energetic particles (EP) resulting from NBI can drive instabilities that are detrimental for the performance and the predictability of plasma discharges. A broad NBI deposition profile, e.g. by off-axis injection aiming near the plasma mid-radius, is often assumed to limit those undesired effects by reducing the radial gradient of the EP density, thus reducing the ``universal'' drive for instabilities. However, this work presents new evidence that off-axis NBI can also lead to undesired effects such as the destabilization of Alfvénic instabilities, as observed in NSTX-U plasmas. Experimental observations indicate that counter propagating toroidal AEs are destabilized as the radial EP density profile becomes hollow as a result of off-axis NBI. Time-dependent analysis with the TRANSP code, augmented by a reduced fast ion transport model (known as kick model), indicates that instabilities are driven by a combination of radial and energy gradients in the EP distribution. Understanding the mechanisms for wave-particle interaction, revealed by the phase space resolved analysis, is the basis to identify strategies to mitigate or suppress the observed instabilities. Work supported by the U.S. Department of Energy, Office of Science, Office of Fusion Energy Sciences under Contract Number DE-AC02-09CH11466.

  5. 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.

  6. Climate impacts on global hot spots of marine biodiversity

    PubMed Central

    Ramírez, Francisco; Afán, Isabel; Davis, Lloyd S.; Chiaradia, André

    2017-01-01

    Human activities drive environmental changes at scales that could potentially cause ecosystem collapses in the marine environment. We combined information on marine biodiversity with spatial assessments of the impacts of climate change to identify the key areas to prioritize for the conservation of global marine biodiversity. This process identified six marine regions of exceptional biodiversity based on global distributions of 1729 species of fish, 124 marine mammals, and 330 seabirds. Overall, these hot spots of marine biodiversity coincide with areas most severely affected by global warming. In particular, these marine biodiversity hot spots have undergone local to regional increasing water temperatures, slowing current circulation, and decreasing primary productivity. Furthermore, when we overlapped these hot spots with available industrial fishery data, albeit coarser than our estimates of climate impacts, they suggest a worrying coincidence whereby the world’s richest areas for marine biodiversity are also those areas mostly affected by both climate change and industrial fishing. In light of these findings, we offer an adaptable framework for determining local to regional areas of special concern for the conservation of marine biodiversity. This has exposed the need for finer-scaled fishery data to assist in the management of global fisheries if the accumulative, but potentially preventable, effect of fishing on climate change impacts is to be minimized within areas prioritized for marine biodiversity conservation. PMID:28261659

  7. SU-F-I-34: How Does Longitudinal Dose Profile Change with Tube Current Distribution in CT?

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

    Li, X; Yang, K; Liu, B

    Purpose: To investigate how longitudinal dose profile D{sub L}(z) in 30 cm-diameter water cylinder change with tube current (mA) distribution and scan length. Methods: A constant and four variable mA distributions from two previous papers [Dixon et al., Med. Phys. 40, 111920 (14pp.) (2013); Zhang et al., Med. Phys. 41, 091911 (9pp.) (2014)] were adopted in three scan lengths of 10, 28.6, and 50 cm, and all mA distributions had the same average mA over scan ranges. Using the symmetry based dose calculation algorithms and the previously published CT dose equilibration data [Li et al., Med. Phys. 40, 031903 (10pp.)more » (2013); 41, 111910 (5pp.) (2014)], the authors calculated DL(z) on the phantom central and peripheral axes. Kolmogorov-Smirnov (K-S) test was used to compare the lineshapes of two arbitrary distributions. Results: In constant mA scans, D{sub L}(z) was “bell-shaped”. In variable mA scans, D{sub L}(z) approximately followed the mA lineshape, and the K-S distance generally changed with mA distribution. The distance decreased with scan length, and was larger on the central axis than on the peripheral axis. However, the opposite trends were found in the K-S distance between the D{sub L}(z) distributions of constant and variable mA distributions. Conclusion: Radiation dose from TCM scan is best evaluated using the specific tube current distribution. A constant mA based evaluation may lead to inconsistent longitudinal dose profile with that of TCM scan. Their difference in lineshape is larger on the phantom peripheral axis than on the central axis and increases with scan length. This work confirms that radiation dose in CT depends on not only local mA but also the overall mA distribution and scan length. On the other hand, the concept of regional tube current may be useful when scan length is large, tube current peaks near scan range edge, or the target site is superficial.« less

  8. Study on the parameters of the scanning system for the 300 keV electron accelerator

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

    Leo, K. W.; Chulan, R. M., E-mail: leo@nm.gov.my; Hashim, S. A.

    2016-01-22

    This paper describes the method to identify the magnetic coil parameters of the scanning system. This locally designed low energy electron accelerator with the present energy of 140 keV will be upgraded to 300 keV. In this accelerator, scanning system is required to deflect the energetic electron beam across a titanium foil in vertical and horizontal direction. The excitation current of the magnetic coil is determined by the energy of the electron beam. Therefore, the magnetic coil parameters must be identified to ensure the matching of the beam energy and excitation coil current. As the result, the essential parameters ofmore » the effective lengths for X-axis and Y-axis have been found as 0.1198 m and 0.1134 m and the required excitation coil currents which is dependenton the electron beam energies have be identified.« less

  9. Method and apparatus for the formation of a spheromak plasma

    DOEpatents

    Jardin, Stephen C.; Yamada, Masaaki; Furth, Harold P.; Okabayashi, Mitcheo

    1984-01-01

    An inductive method and apparatus for forming detached spheromak plasma using a thin-walled metal toroidal ring, with external current leads and internal poloidal and toroidal field coils located inside a vacuum chamber filled with low density hydrogen gas and an external axial field generating coil. The presence of a current in the poloidal field coils, and an externally generated axial field sets up the initial poloidal field configuration in which the field is strongest toward the major axis of the toroid. The internal toroidal-field-generating coil is then pulsed on, ionizing the gas and inducing poloidal current and toroidal magnetic field into the plasma region in the sleeve exterior to and adjacent to the ring and causing the plasma to expand away from the ring and toward the major axis. Next the current in the poloidal field coils in the ring is reversed. This induces toroidal current into the plasma and causes the poloidal magnetic field lines to reconnect. The reconnection continues until substantially all of the plasma is formed in a separated spheromak configuration held in equilibrium by the initial external field.

  10. Robust Diagnosis Method Based on Parameter Estimation for an Interturn Short-Circuit Fault in Multipole PMSM under High-Speed Operation.

    PubMed

    Lee, Jewon; Moon, Seokbae; Jeong, Hyeyun; Kim, Sang Woo

    2015-11-20

    This paper proposes a diagnosis method for a multipole permanent magnet synchronous motor (PMSM) under an interturn short circuit fault. Previous works in this area have suffered from the uncertainties of the PMSM parameters, which can lead to misdiagnosis. The proposed method estimates the q-axis inductance (Lq) of the faulty PMSM to solve this problem. The proposed method also estimates the faulty phase and the value of G, which serves as an index of the severity of the fault. The q-axis current is used to estimate the faulty phase, the values of G and Lq. For this reason, two open-loop observers and an optimization method based on a particle-swarm are implemented. The q-axis current of a healthy PMSM is estimated by the open-loop observer with the parameters of a healthy PMSM. The Lq estimation significantly compensates for the estimation errors in high-speed operation. The experimental results demonstrate that the proposed method can estimate the faulty phase, G, and Lq besides exhibiting robustness against parameter uncertainties.

  11. Effect of anode position on the performance characteristics of a low-power cylindrical Hall thruster

    NASA Astrophysics Data System (ADS)

    Gao, Yuanyuan; Liu, Hui; Hu, Peng; Huang, Hongyan; Yu, Daren

    2017-06-01

    In this paper, the design of a new cylindrical Hall thruster (CHT) is presented. Its anode is separated from the gas distributor, which is made of ceramic. The effect of the anode position on the performance characteristics of the CHT was investigated by mounting a series of anodes with different radii inside the CHT. It is found that progressively positioning the anode away from the axis along the radial direction increases the ion current and reduces the electron current. Meanwhile, the peak energy in the ion energy distribution function increases, and the shape of the ion energy distribution function noticeably narrows; the ion beam in the plume converges. It is suggested that moving the anode away from the axis may strengthen the electron confinement, thus optimizing the ionization efficiency. Additionally, the electric field near the anode appears to deflect toward the axis, which may promote the collimation of the ion beam in the plume. As a result, the overall performance of the CHT is significantly enhanced in our proposed design.

  12. Performance investigation of an innovative Vertical Axis Hydrokinetic Turbine – Straight Blade Cascaded (VAHT-SBC) for low current speed

    NASA Astrophysics Data System (ADS)

    Hantoro, R.; Prananda, J.; Mahmashani, A. W.; Septyaningru, E.; Imanuddin, F.

    2018-05-01

    Research on the development and innovation of Vertical Axis Hydrokinetic Turbine (VAHT) to improve performance has been done. One of the important indicator that affects VAHT’s performance is Coefficient of Performance (Cp). Theoretical Cp value for the VAT (Darrieus) turbine is 0.45. This paper presents the results of a performance investigation for an innovative Vertical Axis Hydrokinetic Turbine – Straight Blade Cascaded (VAHT-SBC) by modifying the number and the arrangement of blades using CFD simulation. Symmetrical NACA 0018 is used for this study, each model is simulated with current speed variation (U - m/s) of 0.5, 1 and 1.5. An increase in Cp value is shown in variation of 9 blades (3 blades cascaded in each arm) with Cp value of 0.396 at TSR of 2.27 which is reach 88% of the theoretical value. Furthermore, the streamline velocity of the pressure contour, velocity streamline and torque fluctuations are also presented in this paper to gain in deep information.

  13. Design of a novel coil satellite centrifuge and its performance on counter-current chromatographic separation of 4-methylumbelliferyl sugar derivatives with organic-aqueous two-phase solvent systems

    PubMed Central

    Shinomiya, Kazufusa; Tokura, Koji; Kimura, Emiru; Takai, Midori; Harikai, Naoki; Yoshida, Kazunori; Yanagidaira, Kazuhiro; Ito, Yoichiro

    2015-01-01

    A new high-speed counter-current chromatograph, named coil satellite centrifuge (CSC), was designed and fabricated in our laboratory. The CSC apparatus produces the satellite motion such that the coiled column simultaneously rotates around the sun axis (the angular velocity, ω1), the planet axis (ω2) and the satellite axis (the central axis of the column) (ω3). In order to achieve this triplicate rotary motion without twisting of the flow tube, the rotation of each axis was determined by the following formula: ω1 = ω2 + ω3. This relation enabled to lay out the flow tube by two different ways, the SS type and the JS type. In the SS type, the flow tube was introduced from the upper side of the apparatus into the sun axis of the first rotary frame and connected to the planet axis of the second rotary frame like a double letter SS. In the JS type, the flow tube was introduced from the bottom of the apparatus into the sun axis reaching the upper side of the planet axis an inversed letter J, followed by distribution as in the SS type. The performance of the apparatus was examined on separation of 4-methylumbelliferyl (MU) sugar derivatives as test samples with organic-aqueous two-phase solvent systems composed of ethyl acetate/1-butanol/water (3 : 2 : 5, v/v) for lower phase mobile and (1 : 4 : 5, v/v) for upper phase mobile. With lower phase mobile, five 4-MU sugar derivatives including β-D-cellobioside (Cel), β-D-glucopyranoside, α-D-mannopyranoside, β-D-fucopyranoside and α-L-fucopyranoside (α-L-Fuc) were separated with the combined rotation around each axis at counterclockwise (CCW) (ω1) – CCW (ω2) – CCW (ω3) by the JS type flow tube distribution. With upper phase mobile, three 4-MU sugar derivatives including α-L-Fuc, β-D-galactopyranoside and Cel were separated with the combined rotation around each axis at clockwise (CW) (ω1) – CW (ω2) – CW (ω3) by the JS type flow tube distribution. A series of experiments on peak resolution and stationary phase retention revealed that better partition efficiencies were obtained at the flow rate of 0.5 mL/min (column 1) and 0.8 mL/min (column 2) for lower phase mobile and 0.2 mL/min (column 1) and 0.4 mL/min (column 2) for upper phase mobile when using the left-handed multilayer coil (total capacity: 57.0 mL for column 1 and 75.0 mL for column 2) under the rotation speeds of approximately ω1 = 300 rpm, ω2 = 150 rpm and ω3 = 150 rpm. PMID:25805719

  14. Samuel Booth | NREL

    Science.gov Websites

    on renewable energy and microgrid projects. He is currently leading work to support the Power Africa also currently helping Marine Corps installation Miramar to build the most advanced installation scale

  15. Long-term Studies of Marine Halogen Release

    NASA Astrophysics Data System (ADS)

    Tschritter, J.; Holla, R.; Frieß, U.; Platt, U.

    2009-04-01

    Institute of Enviromental Physics, Heidelberg, Germany. Long term measurements of atmospheric trace gases using multi-axis DOAS instruments are pursued at the new SOLAS observatory on the island of Sao Vicente, (Cape Verde). This research is part of the SOPRAN (Surface Ocean Processes in the ANthropocene) project (Fördernummer:03F0462F). Reactive halogen species (RHS) such as bromine- and iodine- containing species play major roles in the chemistry of ozone in both the troposphere and lower stratosphere and thus possibly influence the ozone budget on a global scale. In addition iodine-species emitted from the ocean surface have been shown to be responsible for the production of new atmospheric particles in the marine boundary layer. This may have an effect on cloud formation and radiation transfer on local and global scales. Long term measurements of RHS abundances will help to identify their key regions and processes for formation. A new long term Multi-MAX-DOAS instrument has been installed at the SOLAS observatory on the island of Sao Vicente, (Cape Verde). The main focus of these unique measurements is the investigation of reactive halogen chemistry in the subtropical marine boundary layer based on measurements of BrO, IO, and possibly OIO. Because of its wide spectral range also the use for O4-retrievals to gain aerosol profiles is possible. IO has been detected with mixing ratios up to 1.3 ppt. For BrO an upper limit of 2 ppt could be determined.

  16. Research on the fundamental principles of China's marine invasive species prevention legislation.

    PubMed

    Bai, Jiayu

    2014-12-15

    China's coastal area is severely damaged by marine invasive species. Traditional tort theory resolves issues relevant to property damage or personal injuries, through which plaintiffs cannot cope with the ecological damage caused by marine invasive species. Several defects exist within the current legal regimes, such as imperfect management systems, insufficient unified technical standards, and unsound legal responsibility systems. It is necessary to pass legislation to prevent the ecological damage caused by marine invasive species. This investigation probes the fundamental principles needed for the administration and legislation of an improved legal framework to combat the problem of invasive species within China's coastal waters. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Characterization, Preparation, and Purification of Marine Bioactive Peptides

    PubMed Central

    Wang, Xueqin; Yu, Huahua; Xing, Ronge

    2017-01-01

    Marine bioactive peptides, as a source of unique bioactive compounds, are the focus of current research. They exert various biological roles, some of the most crucial of which are antioxidant activity, antimicrobial activity, anticancer activity, antihypertensive activity, anti-inflammatory activity, and so forth, and specific characteristics of the bioactivities are described. This review also describes various manufacturing techniques for marine bioactive peptides using organic synthesis, microwave assisted extraction, chemical hydrolysis, and enzymes hydrolysis. Finally, purification of marine bioactive peptides is described, including gel or size exclusion chromatography, ion-exchange column chromatography, and reversed-phase high-performance liquid chromatography, which are aimed at finding a fast, simple, and effective method to obtain the target peptides. PMID:28761878

  18. A review of parasite studies of commercially important marine fishes in sub-Saharan Africa.

    PubMed

    Reed, Cecile C

    2015-01-01

    Scattered records of parasitic species infecting commercially important marine fishes in sub-Saharan Africa are known from just a few countries where concerted efforts have been made by local parasitologists (e.g. Senegal, Nigeria, South Africa). Most of these consist of taxonomic records or general surveys of parasite faunas associated with marine hosts, which may or may not have been of commercial value. Little to no multi-disciplinary research is conducted in most parts of sub-Saharan Africa and hence parasitological data are not commonly used to advise fisheries management procedures. This review summarizes current knowledge on all parasitological research associated with commercially important marine fish species in sub-Saharan Africa.

  19. Recent off-axis volcanism in the eastern Gulf of Aden: Implications for plume-ridge interaction

    NASA Astrophysics Data System (ADS)

    Leroy, Sylvie; d'Acremont, Elia; Tiberi, Christel; Basuyau, Clémence; Autin, Julia; Lucazeau, Francis; Sloan, Heather

    2010-04-01

    Evidence of anomalous volcanism is readily observed in the Gulf of Aden, although, much of this oceanic basin remains as yet unmapped. In this paper, we investigate the possible connection of the Afar hotspot with a major off-axis volcanic structure and its interpretation as a consequence of a the anomalous presence of melt by integrating several data sets, both published and unpublished, from the Encens-Sheba cruise, the Aden New Century (ANC) cruise and several other onshore and marine surveys. These include bathymetric, gravity, magnetic, magneto-telluric data, and rock samples. Based upon these observations, interpretations were made of seafloor morphology, gravity and magnetic models, seafloor age, geochemical analyses and tectonic setting. We discuss the possible existence of a regional melting anomaly in the Gulf of Aden area and of the probability of its connection to the Afar plume. Several models that might explain the anomalous volcanism are taken into account, such as a local melting anomaly unrelated to the Afar plume, an anomalously large volume of melt associated with seafloor spreading, and interaction of the ridge with the Afar plume. A local melting anomaly and atypical seafloor spreading prove inconsistent with our observations. Two previously proposed models of plume-ridge interactions are examined: the diffuse plume dispersion called pancaked flow and channelized along-axis flow. We conclude that the configuration and structure of this young ocean basin may have the effect of channeling material away from the Afar plume along the Aden and Sheba Ridges to produce the off-axis volcanism observed on the ridge flanks. This interpretation implies that the influence of the Afar hotspot may extend much farther eastwards into the Gulf of Aden than previously believed. The segmentation of the Gulf of Aden and the configuration of the Aden-Sheba system may provide a potential opportunity to study channeled flow of solid plume mantle from the plume along a segmented ridge and nearby continental margins.

  20. C:N:P Molar Ratios, Sources and 14C Dating of Surficial Sediments from the NW Slope of Cuba

    PubMed Central

    de la Lanza Espino, Guadalupe; Soto, Luis A.

    2015-01-01

    The surficial sediments recovered from 12 sites located near the channel axis of the Florida Straits and the lower slope off NW Cuba were analyzed for total organic carbon (TOC), nitrogen (TN), phosphorus (TP), elemental C:N:P ratios, C and N isotopic values, and 14C dating. The depth profiles of TOC, TN, and TP (0-18 cm) displayed a downcore trend and a significant variation. The TOC values were low (0.15 to 0.62%; 66 to 516 µmol g-1). Sites near the island’s lower slope had lower TOC average concentrations (158-333 µmol g-1) than those closer to the channel axis (averaging 341-516 µmol g-1; p <0.05). The TN concentrations near the lower slope attained 0.11% (80 µmol g-1), whereas, towards the channel axis, they decreased to 0.07% (55 µmol g-1; p<0.05). The C:N ratios ranged from 1.9 to 10.2. The mean molar C:N ratio (5.4) indicated a marine hemipelagic deposition. The TP was lower at sites near the lower slope (38.4 to 50.0 µmol g-1; 0.12% to 0.16%) than those near the channel axis (50.0 to 66 µmol g-1; 0.15 to 0.21%). C:P fluctuated from 7.7 to 14.1 in the surficial sediment layer. The bulk organic δ13Corg and δ15N values confirmed pelagic organic sources, and the 14C dating revealed that the sediments were deposited during the Holocene (1000-5000 yr BP). We suggest that the hydrodynamic conditions in the Straits influence vertical and advective fluxes of particulate organic material trapped in the mixed-layer, which reduces the particulate matter flux to the seabed. PMID:26110791

  1. Characterization and differential expression of three GnRH forms during reproductive development in cultured turbot Schophthalmus maximus

    NASA Astrophysics Data System (ADS)

    Zhao, Chunyan; Xu, Shihong; Feng, Chengcheng; Liu, Yifan; Yang, Yang; Wang, Yanfeng; Xiao, Yongshuang; Song, Zongcheng; Liu, Qinghua; Li, Jun

    2017-10-01

    Turbots (Schophthalmus maximus), one of the most important economic marine flatfish species, fail to undergo final spawning and spermiation naturally under artificial farming conditions. In vertebrates, reproduction is regulated by the brain-pituitary-gonadal axis (BPG-axis), and gonadotropin releasing hormone (GnRH) is one of its key components. Therefore, to better understand the physiology of reproduction in the turbot, three of the genes encoding GnRH subtypes—sbGnRH, cGnRH-II and sGnRH—were cloned and sequenced by isolating the cDNA sequences. The localizations and patterns of expression of their mRNAs were also evaluated during seasonal gonadal development. All three mRNAs were expressed abundantly in the brain; sbGnRH and sGnRH mRNAs were also detected in the gonads and pituitary gland, and sbGnRH expression was much higher than that of sGnRH, indicating the critical role of sbGnRH in regulating the BPG-axis. Moreover, the brain expression patterns of sbGnRH and sGnRH mRNAs showed an increased trend during gonadal development, peaking in mature stages. This indicated the direct regulation of gonadal development by the GnRH system. In addition, cGnRH-II mRNA expression showed no significant variations, suggesting that cGnRH-II is not critically involved in the control of reproduction. Further, the mRNA abundances of the three GnRH forms in the breeding season were significantly higher than those in immature and post-breeding stages in all analyzed brain areas. Therefore, we propose that sbGnRH is the most important hormone for the regulation of reproduction in turbot via the BPG-axis. These results will help in better understanding the reproductive endocrine mechanisms of turbots and lay the groundwork for additional studies aimed at comparing the reproductive physiology of wild individuals with those raised under artificial conditions.

  2. Acceleration feedback of a current-following synchronized control algorithm for telescope elevation axis

    NASA Astrophysics Data System (ADS)

    Tang, Tao; Zhang, Tong; Du, Jun-Feng; Ren, Ge; Tian, Jing

    2016-11-01

    This paper proposes a dual-motor configuration to enhance closed-loop performance of a telescope control system. Two identical motors are mounted on each side of a U-type frame to drive the telescope elevation axis instead of a single motor drive, which is usually used in a classical design. This new configuration and mechanism can reduce the motor to half the size used in the former design, and it also provides some other advantages. A master-slave current control mode is employed to synchronize the two motors. Acceleration feedback control is utilized to further enhance the servo performance. Extensive experiments are used to validate the effectiveness of the proposed control algorithm in synchronization, disturbance attenuation and low-velocity tracking.

  3. Stability analysis of offshore wind farm and marine current farm

    NASA Astrophysics Data System (ADS)

    Shawon, Mohammad Hasanuzzaman

    Renewable energy has been playing an important role to meet power demand and 'Green Energy' market is getting bigger platform all over the world in the last few years. Due to massive increase in the prices of fossil fuels along with global warming issues, energy harvesting from renewable energy sources has received considerable interest, nowadays, where extensive researches are going on to ensure optimum use of renewable sources. In order to meet the increasing demand of electricity and power, integration of renewable energy is getting highest priorities around the world. Wind is one of the most top growing renewable energy resources and wind power market penetration is expected to reach 3.35 percent by 2013 from its present market of about 240 GW. A wind energy system is the most environmental friendly, cost effective and safe among all renewable energy resources available. Another promising form of renewable energy is ocean energy which covers 70 % of the earth. Ocean energy can be tapped from waves, tides and thermal elements. Offshore Wind farm (OWF) has already become very popular for large scale wind power integration with the onshore grid. Recently, marine current farm (MCF) is also showing good potential to become mainstream energy sources and already successfully commissioned in United Kingdom. However, squirrel cage induction generator (SCIG) has the stability problem similar to synchronous generator especially during fault location to restore the electromagnetic torque. Series dynamic braking resistor (SDBR) has been known as a useful mean to stabilize fixed speed wind generator system. On the other hand, doubly fed induction generator (DFIG) has the capability of coupling the control of active and reactive power and to provide necessary reactive power demand during grid fault conditions. Series dynamic braking resistor (SDBR) can also be employed with DFIG to limit the rotor over current. An integration of wind and tidal energy represents a new-trend for large electric energy production using offshore wind generators and marine current generators, respectively. Thus DFIG based offshore wind farm can be an economic solution to stabilize squirrel cage induction generator based marine current farm without installing any addition FACTS devices. This thesis first focuses on the stabilization of fixed speed IG based marine current farm using SDBR. Also stabilization of DFIG based variable speed wind farm utilizing SDBR is studied in this work. Finally a co-operative control strategy is proposed where DFIG is controlled in such a way that it can even provide necessary reactive power demand of induction generator, so that additional cost of FACTS devices can be avoided. In that way, the DFIGs of the offshore wind farm (OWF) will actively compensate the reactive power demand of adjacent IGs of the marine current farm (MCF) during grid fault. Detailed modeling and control scheme for the proposed system are demonstrated considering some realistic scenarios. The power system small signal stability analysis is also carried out by eigenvalue analysis for marine current generator topology, wind turbine generator topology and integrated topology. The relation between the modes and state variables are discussed in light of modal and sensitivity analyses. The results of theoretical analyses are verified by MATLAB/SIMULINK and laboratory standard power system simulator PSCAD/EMTDC.

  4. Regularized Biot-Savart Laws for Modeling Magnetic Flux Ropes

    NASA Astrophysics Data System (ADS)

    Titov, Viacheslav; Downs, Cooper; Mikic, Zoran; Torok, Tibor; Linker, Jon A.

    2017-08-01

    Many existing models assume that magnetic flux ropes play a key role in solar flares and coronal mass ejections (CMEs). It is therefore important to develop efficient methods for constructing flux-rope configurations constrained by observed magnetic data and the initial morphology of CMEs. As our new step in this direction, we have derived and implemented a compact analytical form that represents the magnetic field of a thin flux rope with an axis of arbitrary shape and a circular cross-section. This form implies that the flux rope carries axial current I and axial flux F, so that the respective magnetic field is a curl of the sum of toroidal and poloidal vector potentials proportional to I and F, respectively. The vector potentials are expressed in terms of Biot-Savart laws whose kernels are regularized at the rope axis. We regularized them in such a way that for a straight-line axis the form provides a cylindrical force-free flux rope with a parabolic profile of the axial current density. So far, we set the shape of the rope axis by tracking the polarity inversion lines of observed magnetograms and estimating its height and other parameters of the rope from a calculated potential field above these lines. In spite of this heuristic approach, we were able to successfully construct pre-eruption configurations for the 2009 February13 and 2011 October 1 CME events. These applications demonstrate that our regularized Biot-Savart laws are indeed a very flexible and efficient method for energizing initial configurations in MHD simulations of CMEs. We discuss possible ways of optimizing the axis paths and other extensions of the method in order to make it more useful and robust.Research supported by NSF, NASA's HSR and LWS Programs, and AFOSR.

  5. Seasonal variation in sea turtle density and abundance in the southeast Florida current and surrounding waters

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

    Bovery, Caitlin M.; Wyneken, Jeanette

    Assessment and management of sea turtle populations is often limited by a lack of available data pertaining to at-sea distributions at appropriate spatial and temporal resolutions. Assessing the spatial and temporal distributions of marine turtles in an open system poses both observational and analytical challenges due to the turtles’ highly migratory nature. Surface counts of marine turtles in waters along the southern part of Florida’s east coast were made in and adjacent to the southeast portion of the Florida Current using standard aerial surveys during 2011 and 2012 to assess their seasonal presence. This area is of particular concern formore » sea turtles as interest increases in offshore energy developments, specifically harnessing the power of the Florida Current. While it is understood that marine turtles use these waters, here we evaluate seasonal variation in sea turtle abundance and density over two years. Density of sea turtles observed within the study area ranged from 0.003 turtles km-2 in the winter of 2011 to 0.064 turtles km-2 in the spring of 2012. As a result, this assessment of marine turtles in the waters off southeast Florida quantifies their in-water abundance across seasons in this area to establish baselines and inform future management strategies of these protected species.« less

  6. Seasonal variation in sea turtle density and abundance in the southeast Florida current and surrounding waters

    DOE PAGES

    Bovery, Caitlin M.; Wyneken, Jeanette

    2015-12-30

    Assessment and management of sea turtle populations is often limited by a lack of available data pertaining to at-sea distributions at appropriate spatial and temporal resolutions. Assessing the spatial and temporal distributions of marine turtles in an open system poses both observational and analytical challenges due to the turtles’ highly migratory nature. Surface counts of marine turtles in waters along the southern part of Florida’s east coast were made in and adjacent to the southeast portion of the Florida Current using standard aerial surveys during 2011 and 2012 to assess their seasonal presence. This area is of particular concern formore » sea turtles as interest increases in offshore energy developments, specifically harnessing the power of the Florida Current. While it is understood that marine turtles use these waters, here we evaluate seasonal variation in sea turtle abundance and density over two years. Density of sea turtles observed within the study area ranged from 0.003 turtles km-2 in the winter of 2011 to 0.064 turtles km-2 in the spring of 2012. As a result, this assessment of marine turtles in the waters off southeast Florida quantifies their in-water abundance across seasons in this area to establish baselines and inform future management strategies of these protected species.« less

  7. Evaluation of the prototype dual-axis wall attitude measurement sensor

    NASA Technical Reports Server (NTRS)

    Wong, Douglas T.

    1994-01-01

    A prototype dual-axis electrolytic tilt sensor package for angular position measurements was built and evaluated in a laboratory environment. The objective was to investigate the use of this package for making wind tunnel wall attitude measurements for the National Transonic Facility (NTF) at NASA Langley Research Center (LaRC). The instrumentation may replace an existing, more costly, and less rugged servo accelerometer package (angle-of-attack package) currently in use. The dual-axis electrolytic tilt sensor package contains two commercial electrolytic tilt sensors thermally insulated with NTF foam, all housed within a stainless steel package. The package is actively heated and maintained at 160 F using foil heating elements. The laboratory evaluation consisted of a series of tests to characterize the linearity, repeatability, cross-axis interaction, lead wire effect, step response, thermal time constant, and rectification errors. Tests revealed that the total RMS errors for the x-axis sensor is 0.084 degree, and 0.182 degree for the y-axis sensor. The RMS errors are greater than the 0.01 degree specification required for NTF wall attitude measurements. It is therefore not a viable replacement for the angle-of-attack package in the NTF application. However, with some physical modifications, it can be used as an inexpensive 5-degree range dual-axis inclinometer with overall accuracy approaching 0.01 degree under less harsh environments. Also, the data obtained from the tests can be valuable for wind tunnel applications of most types of electrolytic tilt sensors.

  8. Late Tertiary Motion of the Hawaiian Hot Spot Relative to the Spin Axis and Implications for True Polar Wander

    NASA Astrophysics Data System (ADS)

    Gaastra, K.; Gordon, R. G.

    2017-12-01

    Recent work on Pacific plate paleomagnetic poles, when combined with analyses of equatorial sediment facies [Suárez and Molnar, 1980; Gordon and Cape, 1981; Parés and Moore, 2005], demonstrates that the Hawaiian hotspot lay 3° to 4° north of its present latitude during formation of most of the Hawaiian chain [Woodworth et al., this meeting]. Available Pacific plate paleomagnetic and equatorial sediment facies data constrain the hotspot to this latitude from 44 Ma until 12 Ma, with the hotspot shifting to its present latitude since 12 Ma. Comparison with the apparent polar wander of the Indo-Atlantic hotspots inferred from continental paleomagnetic poles combined with plate reconstructions indicates that global hotspots have moved in unison relative to the spin axis since 12 Ma, indicating the occurrence of an episode of true polar wander, but the timing is not well constrained from available data. The direction of the indicated true polar wander is similar to that observed over the past few decades from space geodetic data [Argus and Gross, 2004], which suggests that the same episode of true polar wander may be occurring today.For these reasons we present a skewness analysis of marine magnetic anomaly 3r ( 5.5 Ma) with the goal of limiting the timing and rate of the shift of the Hawaiian hotspot (and other hotspots) relative to the spin axis. We will determine whether the shift occurred partly or entirely in the past 5.5 Ma, which has implications for the hotspot and paleomagnetic reference frames.

  9. Starfish (Asteroidea, Echinodermata) from the Faroe Islands; spatial distribution and abundance

    NASA Astrophysics Data System (ADS)

    Ringvold, H.; Andersen, T.

    2016-01-01

    "Marine benthic fauna of the Faroe Islands" (BIOFAR) is a large programme with a focus on collecting invertebrate fauna from the Faroes (62°N and 7°W). Cruises were undertaken from 1987 to 1990, and starfish (Asteroidea, Echinodermata) collected during this time were analysed. Asteroidea were sampled at ~50% of all BIOFAR stations. A Detritus sledge and a Triangular dredge proved to be the most efficient equipment, collecting over 60% of the specimens. In total 2473 specimens were collected from 20 to 1500 m depth, including 41 species from 17 families and 31 genera. Henricia pertusa (O. F. Müller, 1776) group, Pontaster tenuispinus (Düben & Koren, 1846), and Leptychaster arcticus (M. Sars, 1851) showed highest relative abundance. Maximum species diversity was found at 500-700 m depth, which coincides with the transition zone of water masses (North Icelandic Winter Water and Arctic Intermediate Water (NI/AI)) at approximately 400-600 m depth. 63% of the species were recorded at an average-weighted depth above 600 m. Two different ordination methods (detrended correspondence analysis (DCA) and nonmetric multidimensional scaling (NMDS)) gave highly consistent representations of the community structure gradients. The first ordination axis scores did not show significant relationships with any environmental variable. Biological covariates like the presence of Lophelia corals were not significantly related to ordination scores on any axis. The second ordination axis scores were significantly correlated with depth. Temperature and salinity were highly correlated (r=0.90), and both negatively correlated with depth (r=-0.69 and r=-0.57, respectively).

  10. Identification of Cu’s sources in Jiaozhou Bay

    NASA Astrophysics Data System (ADS)

    Yang, Dongfang; Li, Haixia; Ding, Jun; Zhang, Longlei; Li, Jiangmin

    2017-12-01

    Many marine bays have been polluted by Cu along with the rapid development of industry, economy and population size, and identification the sources of Cu is essential to environmental protection. This paper identified the sources of Cu in according to the horizontal distribution in Jiaozhou Bay during 1982-1986. Results showed that there were five Cu sources during study years including marine current, stream flow, island top, overland runoff and marine traffic, respectively. These findings were helpful information in decision-making of pollution control and environmental remediation practice.

  11. Characterization of bioactive peptides obtained from marine invertebrates.

    PubMed

    Lee, Jung Kwon; Jeon, Joong-Kyun; Kim, Se-Kwon; Byun, Hee-Guk

    2012-01-01

    Bioactive peptides as products of hydrolysis of diverse marine invertebrate (shellfish, crustacean, rotifer, etc.) proteins are the focus of current research. After much research on these muscles and by-products, some biologically active peptides were identified and applied to useful compounds for human utilization. This chapter reviews bioactive peptides from marine invertebrates in regarding to their bioactivities. Additionally, specific characteristics of antihypertensive, anti-Alzheimer, antioxidant, antimicrobial peptide enzymatic production, methods to evaluate bioactivity capacity, bioavailability, and safety concerns of peptides are reviewed. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Limb-use by foraging marine turtles, an evolutionary perspective

    PubMed Central

    McLeish, Don; Brooks, Andrew J.; Gaskell, John; Van Houtan, Kyle S.

    2018-01-01

    The use of limbs for foraging is documented in both marine and terrestrial tetrapods. These behaviors were once believed to be less likely in marine tetrapods due to the physical constraints of body plans adapted to locomotion in a fluid environment. Despite these obstacles, ten distinct types of limb-use while foraging have been previously reported in nine marine tetrapod families. Here, we expand the types of limb-use documented in marine turtles and put it in context with the diversity of marine tetrapods currently known to use limbs for foraging. Additionally, we suggest that such behaviors could have occurred in ancestral turtles, and thus, possibly extend the evolutionary timeline of limb-use behavior in marine tetrapods back approximately 70 million years. Through direct observation in situ and crowd-sourcing, we document the range of behaviors across habitats and prey types, suggesting its widespread occurrence. We argue the presence of these behaviors among marine tetrapods may be limited by limb mobility and evolutionary history, rather than foraging ecology or social learning. These behaviors may also be remnant of ancestral forelimb-use that have been maintained due to a semi-aquatic life history. PMID:29610708

  13. An overview of polybrominated diphenyl ethers (PBDEs) in the marine environment

    NASA Astrophysics Data System (ADS)

    Lee, Hyo Jin; Kim, Gi Beum

    2015-06-01

    Polybrominated diphenyl ethers (PBDEs), which are used extensively as brominated flame retardants, are found ubiquitously in marine environments worldwide. In this paper, we review all available data on the occurrence and trends of PBDEs in marine environments. PBDE levels in different marine environmental compartments vary from nanograms per gram to micrograms per gram, and differ widely, depending on the exposed species and the collection site. The PBDE congener profiles in biota, which are dominated by the lower brominated congeners, such as BDE-47 and BDE-99, are different from those in sediments, where BDE-209 is dominant. Temporal trends in PBDE levels in sediment cores vary considerably, depending on the region or country studied, with possible correlations with the historic and current use of PBDEs. Low brominated BDE congeners have the potential for bioaccumulation in marine organisms, but BDE- 209 has a very low potential for bioaccumulating within the marine food web. The toxicological effects of PBDEs on marine organisms are largely unknown. However, PBDE isomers may be sufficient to elicit adverse effects in some marine organisms. Here, we discuss naturally occurring brominated diphenyl ethers and recommend further research to improve future monitoring.

  14. Ocean noise and marine mammals: A tutorial lecture

    NASA Astrophysics Data System (ADS)

    D'Spain, Gerald; Wartzok, Douglas

    2004-10-01

    The effect of man-made sound on marine mammals has been surrounded by controversy over the past decade. Much of this controversy stems from our lack of knowledge of the effects of noise on marine life. Ocean sound is produced during activities of great benefit to humans: commerce, exploration for energy reserves, national defense, and the study of the ocean environment itself. However, some recent strandings of marine mammals have been associated with the occurrence of human-generated sound. The documented increase of man-made sound in the ocean suggests the potential for more extensive though subtler effects than those observed in the mass strandings. The purpose of this tutorial is to present the scientific issues pertaining to ocean noise and marine mammals. Basic physics of sound in the ocean and long term trends of ocean sound will be presented. The biology of marine mammals, particularly their production, reception and use of sound in monitoring their environment, social interactions, and echolocation, will be reviewed. This background information sets the stage for understanding the effects of man-made sound on marine mammals. The extensive gaps in current knowledge with respect to marine mammal distribution and behavioral and physiological responses to sound will highlight research needs.

  15. Limb-use by foraging marine turtles, an evolutionary perspective.

    PubMed

    Fujii, Jessica A; McLeish, Don; Brooks, Andrew J; Gaskell, John; Van Houtan, Kyle S

    2018-01-01

    The use of limbs for foraging is documented in both marine and terrestrial tetrapods. These behaviors were once believed to be less likely in marine tetrapods due to the physical constraints of body plans adapted to locomotion in a fluid environment. Despite these obstacles, ten distinct types of limb-use while foraging have been previously reported in nine marine tetrapod families. Here, we expand the types of limb-use documented in marine turtles and put it in context with the diversity of marine tetrapods currently known to use limbs for foraging. Additionally, we suggest that such behaviors could have occurred in ancestral turtles, and thus, possibly extend the evolutionary timeline of limb-use behavior in marine tetrapods back approximately 70 million years. Through direct observation in situ and crowd-sourcing, we document the range of behaviors across habitats and prey types, suggesting its widespread occurrence. We argue the presence of these behaviors among marine tetrapods may be limited by limb mobility and evolutionary history, rather than foraging ecology or social learning. These behaviors may also be remnant of ancestral forelimb-use that have been maintained due to a semi-aquatic life history.

  16. The role of sustained observations in tracking impacts of environmental change on marine biodiversity and ecosystems.

    PubMed

    Mieszkowska, N; Sugden, H; Firth, L B; Hawkins, S J

    2014-09-28

    Marine biodiversity currently faces unprecedented threats from multiple pressures arising from human activities. Global drivers such as climate change and ocean acidification interact with regional eutrophication, exploitation of commercial fish stocks and localized pressures including pollution, coastal development and the extraction of aggregates and fuel, causing alteration and degradation of habitats and communities. Segregating natural from anthropogenically induced change in marine ecosystems requires long-term, sustained observations of marine biota. In this review, we outline the history of biological recording in the coastal and shelf seas of the UK and Ireland and highlight where sustained observations have contributed new understanding of how anthropogenic activities have impacted on marine biodiversity. The contributions of sustained observations, from those collected at observatories, single station platforms and multiple-site programmes to the emergent field of multiple stressor impacts research, are discussed, along with implications for management and sustainable governance of marine resources in an era of unprecedented use of the marine environment. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  17. Enzyme-Assisted Discovery of Antioxidant Peptides from Edible Marine Invertebrates: A Review

    PubMed Central

    Chai, Tsun-Thai; Law, Yew-Chye; Wong, Fai-Chu; Kim, Se-Kwon

    2017-01-01

    Marine invertebrates, such as oysters, mussels, clams, scallop, jellyfishes, squids, prawns, sea cucumbers and sea squirts, are consumed as foods. These edible marine invertebrates are sources of potent bioactive peptides. The last two decades have seen a surge of interest in the discovery of antioxidant peptides from edible marine invertebrates. Enzymatic hydrolysis is an efficient strategy commonly used for releasing antioxidant peptides from food proteins. A growing number of antioxidant peptide sequences have been identified from the enzymatic hydrolysates of edible marine invertebrates. Antioxidant peptides have potential applications in food, pharmaceuticals and cosmetics. In this review, we first give a brief overview of the current state of progress of antioxidant peptide research, with special attention to marine antioxidant peptides. We then focus on 22 investigations which identified 32 antioxidant peptides from enzymatic hydrolysates of edible marine invertebrates. Strategies adopted by various research groups in the purification and identification of the antioxidant peptides will be summarized. Structural characteristic of the peptide sequences in relation to their antioxidant activities will be reviewed. Potential applications of the peptide sequences and future research prospects will also be discussed. PMID:28212329

  18. Enzyme-Assisted Discovery of Antioxidant Peptides from Edible Marine Invertebrates: A Review.

    PubMed

    Chai, Tsun-Thai; Law, Yew-Chye; Wong, Fai-Chu; Kim, Se-Kwon

    2017-02-16

    Marine invertebrates, such as oysters, mussels, clams, scallop, jellyfishes, squids, prawns, sea cucumbers and sea squirts, are consumed as foods. These edible marine invertebrates are sources of potent bioactive peptides. The last two decades have seen a surge of interest in the discovery of antioxidant peptides from edible marine invertebrates. Enzymatic hydrolysis is an efficient strategy commonly used for releasing antioxidant peptides from food proteins. A growing number of antioxidant peptide sequences have been identified from the enzymatic hydrolysates of edible marine invertebrates. Antioxidant peptides have potential applications in food, pharmaceuticals and cosmetics. In this review, we first give a brief overview of the current state of progress of antioxidant peptide research, with special attention to marine antioxidant peptides. We then focus on 22 investigations which identified 32 antioxidant peptides from enzymatic hydrolysates of edible marine invertebrates. Strategies adopted by various research groups in the purification and identification of the antioxidant peptides will be summarized. Structural characteristic of the peptide sequences in relation to their antioxidant activities will be reviewed. Potential applications of the peptide sequences and future research prospects will also be discussed.

  19. A single axis electrostatic beam deflection system for a 5-cm diameter ion thruster

    NASA Technical Reports Server (NTRS)

    Lathem, W. C.

    1972-01-01

    A single-axis electrostatic beam deflection system has been tested on a 5-cm diameter mercury ion thruster at a thrust level of about 0.43 mlb (25 mA beam current at 1400 volts). The accelerator voltage was 500 volts. Beam deflection capability of plus or minus 10 deg was demonstrated. A life test of 1367 hours was run at the above conditions. Results of the test indicated that the system could possibly perform for upwards of 10,000 hours.

  20. Electric power from vertical-axis wind turbines

    NASA Astrophysics Data System (ADS)

    Touryan, K. J.; Strickland, J. H.; Berg, D. E.

    1987-12-01

    Significant advancements have occurred in vertical axis wind turbine (VAWT) technology for electrical power generation over the last decade; in particular, well-proven aerodynamic and structural analysis codes have been developed for Darrieus-principle wind turbines. Machines of this type have been built by at least three companies, and about 550 units of various designs are currently in service in California wind farms. Attention is presently given to the aerodynamic characteristics, structural dynamics, systems engineering, and energy market-penetration aspects of VAWTs.

  1. Tokamak with liquid metal toroidal field coil

    DOEpatents

    Ohkawa, Tihiro; Schaffer, Michael J.

    1981-01-01

    Tokamak apparatus includes a pressure vessel for defining a reservoir and confining liquid therein. A toroidal liner disposed within the pressure vessel defines a toroidal space within the liner. Liquid metal fills the reservoir outside said liner. Electric current is passed through the liquid metal over a conductive path linking the toroidal space to produce a toroidal magnetic field within the toroidal space about the major axis thereof. Toroidal plasma is developed within the toroidal space about the major axis thereof.

  2. The Writhe of Helical Structures in the Solar Corona

    DTIC Science & Technology

    2010-04-23

    1997). Coronal currents store the energy required to power eruptions (Forbes 2000). Indeed, it has been shown that active regions exhibiting a...the twist of the field lines about the magnetic axis of the rope into writhe of the axis. In doing so, it lowers the magnetic energy by reduc- ing the...NNH06AD58I and NNX08AG44G. Financial sup- port by the European Comission through the SOLAIRE network (MTRM-CT- 2006-035484) is gratefully acknowledged. The

  3. Pleistocene reduction of polar ice caps: Evidence from Cariaco Basin marine sediments

    USGS Publications Warehouse

    Poore, R.Z.; Dowsett, H.J.

    2001-01-01

    Sea level is projected to rise between 13 and 94 cm over the next 100 yr due to continued climate warming. The sea-level projections assume that polar ice sheets will remain stable or even increase on time scales of centuries, but controversial geologic evidence suggests that current polar ice sheets have been eliminated or greatly reduced during previous Pleistocene interglacials indicating that modern polar ice sheets have become unstable within the natural range of interglacial climates. Sea level may have been more than 20 m higher than today during a presumably very warm interglacial about 400 ka during marine isotope stage 11. Because of the implications for future sea level rise, additional study of the conflicting evidence for warmer conditions and higher sea level during marine isotope stage 11 is needed. Here we present microfossil and isotopic data from marine sediments of the Cariaco Basin supporting the interpretation that global sea level was 10-20 m higher than today during marine isotope stage 11. The increased sea level requires reduction in modern polar ice sheets and is consistent with the interpretation that the West Antarctic ice sheet and the Greenland ice sheet were absent or greatly reduced during marine isotope stage 11. Our results show a warm marine isotope stage 11 interglacial climate with sea level as high as or above modern sea level that lasted for 25 to 30 k.y. Variations in Earth's orbit around the sun (Milankovitch cycles) are considered to be a primary external force driving glacial-interglacial cycles. Current and marine isotope stage 11 Milankovitch forcing are very similar, suggesting that the present interglacial (Holocene) that began ca. 10 ka will continue for another 15 to 20 k.y. Therefore any anthropogenic climate warming will accelerate the natural process toward reduction in polar ice sheets. The potential for increased rates of sea level rise related to polar ice sheet decay should be considered as a potential natural hazard on centennial time scales.

  4. Reliability, Maintenance and Risk Assessment in Naval Architecture and Marine Engineering Education in the US.

    ERIC Educational Resources Information Center

    Inozu, Bahadir; Ayyub, Bilal A.

    1999-01-01

    Examines the current status of existing curricula, accreditation requirements, and new developments in Naval Architecture and Marine Engineering education in the United States. Discusses the emerging needs of the maritime industry in light of advances in information technology and movement toward risk-based, reliability-centered rule making in the…

  5. 77 FR 41168 - Marine Mammals; Subsistence Taking of Northern Fur Seals; St. Paul Island

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-12

    ... Mammals; Subsistence Taking of Northern Fur Seals; St. Paul Island AGENCY: National Marine Fisheries... taking of northern fur seals on St. Paul Island. St. Paul's petition requests that NMFS revise the... seals; take a total of up to 3,000 fur seals annually compared to 2,000 currently allowed, including up...

  6. 77 FR 45268 - Taking of Marine Mammals Incidental to Commercial Fishing Operations; Bottlenose Dolphin Take...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-31

    ... proposed rule via mail, fax, or www.regulations.gov . Comments were received from The Humane Society of the United States and the Whale and Dolphin Conservation Society, the Marine Mammal Commission, the United... currently described in two BDTRP definitions. NMFS proposed to modify the border latitude from 33[deg]52' N...

  7. The influence of ocean halogen and sulfur emissions in the air quality of a coastal megacity: The case of Los Angeles

    EPA Science Inventory

    The oceans are the main source of natural halogen and sulfur compounds, which have a significant influence on the oxidizing capacity of the marine atmosphere; however, their impact on the air quality of coastal cities is currently unknown. We explore the effect of marine halogens...

  8. 78 FR 43165 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to a...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-19

    ... subsistence uses (where relevant), and if the permissible methods of taking and requirements pertaining to the... application of that technology. CSDS-5 currently moors and operates a research barge at the Service Pier on NBKB and plans to install mooring for a new larger research barge equipped with upgraded technology...

  9. Assessment of Current and Future Air Pollutant Emission Reduction Technologies for Marine Diesel Engines

    DTIC Science & Technology

    2014-02-01

    33 6.3.1 Biodiesel ...6.3 Alternative Fuels There is some consideration of alternatives to liquid fossil oil fuels for the marine industry. Three of these are biodiesel ...Liquefied Natural Gas and Methanol – Dimethyl Ether. 6.3.1 Biodiesel An extensive review across many transportation sectors of the emissions of

  10. Polysaccharides from the Marine Environment with Pharmacological, Cosmeceutical and Nutraceutical Potential.

    PubMed

    Ruocco, Nadia; Costantini, Susan; Guariniello, Stefano; Costantini, Maria

    2016-04-27

    Carbohydrates, also called saccharides, are molecules composed of carbon, hydrogen, and oxygen. They are the most abundant biomolecules and essential components of many natural products and have attracted the attention of researchers because of their numerous human health benefits. Among carbohydrates the polysaccharides represent some of the most abundant bioactive substances in marine organisms. In fact, many marine macro- and microorganisms are good resources of carbohydrates with diverse applications due to their biofunctional properties. By acting on cell proliferation and cycle, and by modulating different metabolic pathways, marine polysaccharides (including mainly chitin, chitosan, fucoidan, carrageenan and alginate) also have numerous pharmaceutical activities, such as antioxidative, antibacterial, antiviral, immuno-stimulatory, anticoagulant and anticancer effects. Moreover, these polysaccharides have many general beneficial effects for human health, and have therefore been developed into potential cosmeceuticals and nutraceuticals. In this review we describe current advances in the development of marine polysaccharides for nutraceutical, cosmeceutical and pharmacological applications. Research in this field is opening new doors for harnessing the potential of marine natural products.

  11. The development of marine renewable energy in China: prospects, challenges and recommendations

    NASA Astrophysics Data System (ADS)

    Wang, Ji; Wang, Haifeng; Liu, Yuxin; Chen, Libo; Tang, Jiuting

    2018-02-01

    In this paper, resources distribution and technology status of tidal energy, wave energy, tidal current energy, ocean thermal energy and salinity gradient energy in China is reviewed, and assessment and advices are given for each category. By analysis, we believe that marine renewable energy is a necessary addition to existent renewable energy to meet the energy demand of the areas and islands where traditional forms of energy are not applicable and it is of great importance in adjusting energy structure of China. This paper describes the potential of marine renewable energy in China, and explores the possible role in future energy systems. As the paper discusses, building on these initiatives, and “realizing” the accelerated development of marine energy, presents a number of challenges. This paper describes a scenario for the accelerated development of marine renewable energy in China from now to 2030. Finally, this paper provides recommendations for future development of marine renewable energy in China.

  12. Marine viruses discovered via metagenomics shed light on viral strategies throughout the oceans

    NASA Astrophysics Data System (ADS)

    Coutinho, Felipe H.; Silveira, Cynthia B.; Gregoracci, Gustavo B.; Thompson, Cristiane C.; Edwards, Robert A.; Brussaard, Corina P. D.; Dutilh, Bas E.; Thompson, Fabiano L.

    2017-07-01

    Marine viruses are key drivers of host diversity, population dynamics and biogeochemical cycling and contribute to the daily flux of billions of tons of organic matter. Despite recent advancements in metagenomics, much of their biodiversity remains uncharacterized. Here we report a data set of 27,346 marine virome contigs that includes 44 complete genomes. These outnumber all currently known phage genomes in marine habitats and include members of previously uncharacterized lineages. We designed a new method for host prediction based on co-occurrence associations that reveals these viruses infect dominant members of the marine microbiome such as Prochlorococcus and Pelagibacter. A negative association between host abundance and the virus-to-host ratio supports the recently proposed Piggyback-the-Winner model of reduced phage lysis at higher host densities. An analysis of the abundance patterns of viruses throughout the oceans revealed how marine viral communities adapt to various seasonal, temperature and photic regimes according to targeted hosts and the diversity of auxiliary metabolic genes.

  13. Marine Invertebrate Metabolites with Anticancer Activities: Solutions to the “Supply Problem”

    PubMed Central

    Gomes, Nelson G. M.; Dasari, Ramesh; Chandra, Sunena; Kiss, Robert; Kornienko, Alexander

    2016-01-01

    Marine invertebrates provide a rich source of metabolites with anticancer activities and several marine-derived agents have been approved for the treatment of cancer. However, the limited supply of promising anticancer metabolites from their natural sources is a major hurdle to their preclinical and clinical development. Thus, the lack of a sustainable large-scale supply has been an important challenge facing chemists and biologists involved in marine-based drug discovery. In the current review we describe the main strategies aimed to overcome the supply problem. These include: marine invertebrate aquaculture, invertebrate and symbiont cell culture, culture-independent strategies, total chemical synthesis, semi-synthesis, and a number of hybrid strategies. We provide examples illustrating the application of these strategies for the supply of marine invertebrate-derived anticancer agents. Finally, we encourage the scientific community to develop scalable methods to obtain selected metabolites, which in the authors’ opinion should be pursued due to their most promising anticancer activities. PMID:27213412

  14. Vanadium pentoxide nanoparticles mimic vanadium haloperoxidases and thwart biofilm formation

    NASA Astrophysics Data System (ADS)

    Natalio, Filipe; André, Rute; Hartog, Aloysius F.; Stoll, Brigitte; Jochum, Klaus Peter; Wever, Ron; Tremel, Wolfgang

    2012-08-01

    Marine biofouling--the colonization of small marine microorganisms on surfaces that are directly exposed to seawater, such as ships' hulls--is an expensive problem that is currently without an environmentally compatible solution. Biofouling leads to increased hydrodynamic drag, which, in turn, causes increased fuel consumption and greenhouse gas emissions. Tributyltin-free antifouling coatings and paints based on metal complexes or biocides have been shown to efficiently prevent marine biofouling. However, these materials can damage the environment through metal leaching (for example, of copper and zinc) and bacteria resistance. Here, we show that vanadium pentoxide nanowires act like naturally occurring vanadium haloperoxidases to prevent marine biofouling. In the presence of bromide ions and hydrogen peroxide, the nanowires catalyse the oxidation of bromide ions to hypobromous acid (HOBr). Singlet molecular oxygen (1O2) is formed and this exerts strong antibacterial activity, which prevents marine biofouling without being toxic to marine biota. Vanadium pentoxide nanowires have the potential to be an alternative approach to conventional anti-biofouling agents.

  15. Marine pharmacology in 2001–2002: Marine compounds with anthelmintic, antibacterial, anticoagulant, antidiabetic, antifungal, anti-inflammatory, antimalarial, antiplatelet, antiprotozoal, antituberculosis, and antiviral activities; affecting the cardiovascular, immune and nervous systems and other miscellaneous mechanisms of action

    PubMed Central

    Mayer, Alejandro M.S.; Hamann, Mark T.

    2016-01-01

    During 2001–2002, research on the pharmacology of marine chemicals continued to be global in nature involving investigators from Argentina, Australia, Brazil, Canada, China, Denmark, France, Germany, India, Indonesia, Israel, Italy, Japan, Mexico, Netherlands, New Zealand, Pakistan, the Philippines, Russia, Singapore, Slovenia, South Africa, South Korea, Spain, Sweden, Switzerland, Thailand, United Kingdom, and the United States. This current article, a sequel to the authors’ 1998, 1999 and 2000 marine pharmacology reviews, classifies 106 marine chemicals derived from a diverse group of marine animals, algae, fungi and bacteria, on the basis of peer-reviewed preclinical pharmacology. Anthelmintic, antibacterial, anticoagulant, antifungal, antimalarial, antiplatelet, antiprotozoal, antituberculosis or antiviral activities were reported for 56 marine chemicals. An additional 19 marine compounds were shown to have significant effects on the cardiovascular, immune and nervous system as well as to possess anti-inflammatory and antidiabetic effects. Finally, 31 marine compounds were reported to act on a variety of molecular targets and thus may potentially contribute to several pharmacological classes. Thus, during 2001–2002 pharmacological research with marine chemicals continued to contribute potentially novel chemical leads for the ongoing global search for therapeutic agents for the treatment of multiple disease categories. PMID:15919242

  16. Marine heatwaves off eastern Tasmania: Trends, interannual variability, and predictability

    NASA Astrophysics Data System (ADS)

    Oliver, Eric C. J.; Lago, Véronique; Hobday, Alistair J.; Holbrook, Neil J.; Ling, Scott D.; Mundy, Craig N.

    2018-02-01

    Surface waters off eastern Tasmania are a global warming hotspot. Here, mean temperatures have been rising over several decades at nearly four times the global average rate, with concomitant changes in extreme temperatures - marine heatwaves. These changes have recently caused the marine biodiversity, fisheries and aquaculture industries off Tasmania's east coast to come under stress. In this study we quantify the long-term trends, variability and predictability of marine heatwaves off eastern Tasmania. We use a high-resolution ocean model for Tasmania's eastern continental shelf. The ocean state over the 1993-2015 period is hindcast, providing daily estimates of the three-dimensional temperature and circulation fields. Marine heatwaves are identified at the surface and subsurface from ocean temperature time series using a consistent definition. Trends in marine heatwave frequency are positive nearly everywhere and annual marine heatwave days and penetration depths indicate significant positive changes, particularly off southeastern Tasmania. A decomposition into modes of variability indicates that the East Australian Current is the dominant driver of marine heatwaves across the domain. Self-organising maps are used to identify 12 marine heatwave types, each with its own regionality, seasonality, and associated large-scale oceanic and atmospheric circulation patterns. The implications of this work for marine ecosystems and their management were revealed through review of past impacts and stakeholder discussions regarding use of these data.

  17. Numerical simulations of current generation and dynamo excitation in a mechanically forced turbulent flow.

    PubMed

    Bayliss, R A; Forest, C B; Nornberg, M D; Spence, E J; Terry, P W

    2007-02-01

    The role of turbulence in current generation and self-excitation of magnetic fields has been studied in the geometry of a mechanically driven, spherical dynamo experiment, using a three-dimensional numerical computation. A simple impeller model drives a flow that can generate a growing magnetic field, depending on the magnetic Reynolds number Rm=micro0sigmaVa and the fluid Reynolds number Re=Vanu of the flow. For Re<420, the flow is laminar and the dynamo transition is governed by a threshold of Rmcrit=100, above which a growing magnetic eigenmode is observed that is primarily a dipole field transverse to the axis of symmetry of the flow. In saturation, the Lorentz force slows the flow such that the magnetic eigenmode becomes marginally stable. For Re>420 and Rm approximately 100 the flow becomes turbulent and the dynamo eigenmode is suppressed. The mechanism of suppression is a combination of a time varying large-scale field and the presence of fluctuation driven currents (such as those predicted by the mean-field theory), which effectively enhance the magnetic diffusivity. For higher Rm, a dynamo reappears; however, the structure of the magnetic field is often different from the laminar dynamo. It is dominated by a dipolar magnetic field aligned with the axis of symmetry of the mean-flow, which is apparently generated by fluctuation-driven currents. The magnitude and structure of the fluctuation-driven currents have been studied by applying a weak, axisymmetric seed magnetic field to laminar and turbulent flows. An Ohm's law analysis of the axisymmetric currents allows the fluctuation-driven currents to be identified. The magnetic fields generated by the fluctuations are significant: a dipole moment aligned with the symmetry axis of the mean-flow is generated similar to those observed in the experiment, and both toroidal and poloidal flux expulsion are observed.

  18. Ocean acidification changes the male fitness landscape.

    PubMed

    Campbell, Anna L; Levitan, Don R; Hosken, David J; Lewis, Ceri

    2016-08-17

    Sperm competition is extremely common in many ecologically important marine taxa. Ocean acidification (OA) is driving rapid changes to the marine environments in which freely spawned sperm operate, yet the consequences of OA on sperm performance are poorly understood in the context of sperm competition. Here, we investigated the impacts of OA (+1000 μatm pCO2) on sperm competitiveness for the sea urchin Paracentrotus lividus. Males with faster sperm had greater competitive fertilisation success in both seawater conditions. Similarly, males with more motile sperm had greater sperm competitiveness, but only under current pCO2 levels. Under OA the strength of this association was significantly reduced and there were male sperm performance rank changes under OA, such that the best males in current conditions are not necessarily best under OA. Therefore OA will likely change the male fitness landscape, providing a mechanism by which environmental change alters the genetic landscape of marine species.

  19. Ocean acidification changes the male fitness landscape

    NASA Astrophysics Data System (ADS)

    Campbell, Anna L.; Levitan, Don R.; Hosken, David J.; Lewis, Ceri

    2016-08-01

    Sperm competition is extremely common in many ecologically important marine taxa. Ocean acidification (OA) is driving rapid changes to the marine environments in which freely spawned sperm operate, yet the consequences of OA on sperm performance are poorly understood in the context of sperm competition. Here, we investigated the impacts of OA (+1000 μatm pCO2) on sperm competitiveness for the sea urchin Paracentrotus lividus. Males with faster sperm had greater competitive fertilisation success in both seawater conditions. Similarly, males with more motile sperm had greater sperm competitiveness, but only under current pCO2 levels. Under OA the strength of this association was significantly reduced and there were male sperm performance rank changes under OA, such that the best males in current conditions are not necessarily best under OA. Therefore OA will likely change the male fitness landscape, providing a mechanism by which environmental change alters the genetic landscape of marine species.

  20. Anticancer drug discovery from the marine environment.

    PubMed

    Nastrucci, Candida; Cesario, Alfredo; Russo, Patrizia

    2012-05-01

    Discovery, isolation, biochemical/pharmacological characterization, pre-clinical and clinical trials of drugs derived from the marine environment are continuously developing and increasing. One of the most promising area is cancer therapy. Currently, there are two drugs approved by the Food and Drug Administration (FDA) and European Agency for the Evaluation of Medicinal Products (EMA) in cancer treatment, namely Cytarabine (Cytosar-U1®) and Eribulin (E7389 or Halaven®). Trabectedin (ET-743 or Yondelis1®), approved by EMA, is completing key Phase III studies in the U.S. for final approval. It was estimated that 118 marine natural products (MNPs) are currently in preclinical trials, 22 MNPs in clinical trials and 3 MNPs on the market. The characteristics and selectivity profiles of new drugs for cancer therapy, as well as drugs disclosed in related patent applications, will be the focus of this review, providing a brief and ready to use reference.

  1. The JPL Mars gravity field, Mars50c, based upon Viking and Mariner 9 Doppler tracking data

    NASA Technical Reports Server (NTRS)

    Konopliv, Alexander S.; Sjogren, William L.

    1995-01-01

    This report summarizes the current JPL efforts of generating a Mars gravity field from Viking 1 and 2 and Mariner 9 Doppler tracking data. The Mars 50c solution is a complete gravity field to degree and order 50 with solutions as well for the gravitational mass of Mars, Phobos, and Deimos. The constants and models used to obtain the solution are given and the method for determining the gravity field is presented. The gravity field is compared to the best current gravity GMM1 of Goddard Space Flight Center.

  2. Status of marine biomedical research.

    PubMed Central

    Bessey, O

    1976-01-01

    A meeting on Marine Biomedical Research, sponsored by the National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health and the Smithsonian Institution Museum of Natural History, was attended by approximately 125 scientists, directors and representatives from many of the country's marine biological laboratories, and government agencies whose interests and responsibilites are in the marine biology and health areas. The purpose of the meeting was to explore the undeveloped research opportunities in the area of marine biology for the advancement of our understanding of human health problems and to provide information on the current status of marine biology laboratories. The meeting was devoted to presentations and discussions in four general areas: (1)Marine Species as Models for Human Disease; (2)Environmental Carcinogenesis and Mutagenesis; (3)Human Health and the Marine Environment--infectious agents and naturally occurring and foreign toxins; and (4)Drugs from the seas. Representatives from twelve of the country's approximatley 40 marine laboratories discussed their organization, developmental history, scientific programs, facilities, and present status of their support. The presentations served as a background and stimulated very lively analytical and constructive discussions of the undeveloped research and education potential residing in the marine environment and biological laboratories for a better understanding of many human health problems; some scientific areas that should be developed to realize this potential; and the needs and problems of marine laboratories that require attention and support if they are to survive and realize their possibilities. PMID:944630

  3. Do freshwater fishes diversify faster than marine fishes? A test using state-dependent diversification analyses and molecular phylogenetics of new world silversides (atherinopsidae).

    PubMed

    Bloom, Devin D; Weir, Jason T; Piller, Kyle R; Lovejoy, Nathan R

    2013-07-01

    Freshwater habitats make up only ∼0.01% of available aquatic habitat and yet harbor 40% of all fish species, whereas marine habitats comprise >99% of available aquatic habitat and have only 60% of fish species. One possible explanation for this pattern is that diversification rates are higher in freshwater habitats than in marine habitats. We investigated diversification in marine and freshwater lineages in the New World silverside fish clade Menidiinae (Teleostei, Atherinopsidae). Using a time-calibrated phylogeny and a state-dependent speciation-extinction framework, we determined the frequency and timing of habitat transitions in Menidiinae and tested for differences in diversification parameters between marine and freshwater lineages. We found that Menidiinae is an ancestrally marine lineage that independently colonized freshwater habitats four times followed by three reversals to the marine environment. Our state-dependent diversification analyses showed that freshwater lineages have higher speciation and extinction rates than marine lineages. Net diversification rates were higher (but not significant) in freshwater than marine environments. The marine lineage-through time (LTT) plot shows constant accumulation, suggesting that ecological limits to clade growth have not slowed diversification in marine lineages. Freshwater lineages exhibited an upturn near the recent in their LTT plot, which is consistent with our estimates of high background extinction rates. All sequence data are currently being archived on Genbank and phylogenetic trees archived on Treebase. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  4. Renin-angiotensin system: an old player with novel functions in skeletal muscle.

    PubMed

    Cabello-Verrugio, Claudio; Morales, María Gabriela; Rivera, Juan Carlos; Cabrera, Daniel; Simon, Felipe

    2015-05-01

    Skeletal muscle is a tissue that shows the most plasticity in the body; it can change in response to physiological and pathological stimuli. Among the diseases that affect skeletal muscle are myopathy-associated fibrosis, insulin resistance, and muscle atrophy. A common factor in these pathologies is the participation of the renin-angiotensin system (RAS). This system can be functionally separated into the classical and nonclassical RAS axis. The main components of the classical RAS pathway are angiotensin-converting enzyme (ACE), angiotensin II (Ang-II), and Ang-II receptors (AT receptors), whereas the nonclassical axis is composed of ACE2, angiotensin 1-7 [Ang (1-7)], and the Mas receptor. Hyperactivity of the classical axis in skeletal muscle has been associated with insulin resistance, atrophy, and fibrosis. In contrast, current evidence supports the action of the nonclassical RAS as a counter-regulator axis of the classical RAS pathway in skeletal muscle. In this review, we describe the mechanisms involved in the pathological effects of the classical RAS, advances in the use of pharmacological molecules to inhibit this axis, and the beneficial effects of stimulation of the nonclassical RAS pathway on insulin resistance, atrophy, and fibrosis in skeletal muscle. © 2015 Wiley Periodicals, Inc.

  5. Unusual calcite cementing of quartz grains on Chandeleur Island Beach, offshore Louisiana

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

    Mitchell-Tapping, H.J.

    1983-09-01

    A very unusual calcite cement was found in some beachchips from an unconsolidated beach surface of Chandeleur Island offshore approximately 35 nmi (65 km) south of Mississippi in the Gulf of Mexico. The beachchips are irregularly shaped and are well cemented by this unusual calcite. This calcite crystal structure has not been reported previously as existing in a marine environment. A similar cement has been found in freshwater lake beachrock and in some travertine samples. The calcite crystals are elongate parallel to the c-optic axis, and are composed of bunches of crystallite blades. The crystallite blades of each crystal bunchmore » are pointed and are more bladed than freshwater cement crystals. The intercrystallite pore space contains no fine calcite silt as was observed in the lake samples. Fresh water provided by rainfall may be held in the pore spaces and bounded to the quartz-grain surfaces by ionic attraction. Marine spray above and saline water concentrated underneath from a sandwich effect at the micropore level, allowing rapid growth and precipitation of these very unusual calcite crystals in a single-phase low-salinity fluid.« less

  6. Differences in boldness are repeatable and heritable in a long-lived marine predator

    PubMed Central

    Patrick, Samantha C; Charmantier, Anne; Weimerskirch, Henri

    2013-01-01

    Animal personalities, composed of axes of consistent individual behaviors, are widely reported and can have important fitness consequences. However, despite theoretical predictions that life-history trade-offs may cause and maintain personality differences, our understanding of the evolutionary ecology of personality remains poor, especially in long-lived species where trade-offs and senescence have been shown to be stronger. Furthermore, although much theoretical and empirical work assumes selection shapes variation in personalities, studies exploring the genetic underpinnings of personality traits are rare. Here we study one standard axis of personality, the shy–bold continuum, in a long-lived marine species, the wandering albatross from Possession Island, Crozet, by measuring the behavioral response to a human approach. Using generalized linear mixed models in a Bayesian framework, we show that boldness is highly repeatable and heritable. We also find strong differences in boldness between breeding colonies, which vary in size and density, suggesting birds are shyer in more dense colonies. These results demonstrate that in this seabird population, boldness is both heritable and repeatable and highlights the potential for ecological and evolutionary processes to shape personality traits in species with varying life-history strategies. PMID:24340172

  7. Differences in boldness are repeatable and heritable in a long-lived marine predator.

    PubMed

    Patrick, Samantha C; Charmantier, Anne; Weimerskirch, Henri

    2013-11-01

    Animal personalities, composed of axes of consistent individual behaviors, are widely reported and can have important fitness consequences. However, despite theoretical predictions that life-history trade-offs may cause and maintain personality differences, our understanding of the evolutionary ecology of personality remains poor, especially in long-lived species where trade-offs and senescence have been shown to be stronger. Furthermore, although much theoretical and empirical work assumes selection shapes variation in personalities, studies exploring the genetic underpinnings of personality traits are rare. Here we study one standard axis of personality, the shy-bold continuum, in a long-lived marine species, the wandering albatross from Possession Island, Crozet, by measuring the behavioral response to a human approach. Using generalized linear mixed models in a Bayesian framework, we show that boldness is highly repeatable and heritable. We also find strong differences in boldness between breeding colonies, which vary in size and density, suggesting birds are shyer in more dense colonies. These results demonstrate that in this seabird population, boldness is both heritable and repeatable and highlights the potential for ecological and evolutionary processes to shape personality traits in species with varying life-history strategies.

  8. Geomorphic reconstructions in the environs of ancient troy.

    PubMed

    Kraft, J C; Kayan, I; Erol, O

    1980-08-15

    Sea level rise, deltaic progradation, and floodplain aggradation have changed the landscape in the vicinity of ancient Troy during the past 10,000 years. With the waning of the last major world glaciation and resultant sea level rise and fluctuation, a marine embayment protruded nearly 10 kilometers south of the site of Troy at Hisarlik in the Troad of northwest Turkey. As the sea approached its present level approximately 6000 years ago, fluvial and marine deposition caused a northerly migration of the delta and floodplain of the Scamander and Simois Rivers past the site of Troy toward the present-day coast about 6 kilometers north of the site. In view of these major changes in morphology, interpretations of ancient geographies related to historical or historical-mythological settings must be changed. A number of paleogeographic maps have been reconstructed with the use of subsurface data that records the continuing landscape change since the first occupancy of the site at Troy 5000 years ago. These show that ancient Troy was located on an embayment of the sea. If the Trojan War occurred, then the axis of the battlefield and associated events must be relocated to the south and west of Troy.

  9. Signal Acquisition Using AXIe

    NASA Astrophysics Data System (ADS)

    Narciso, Steven J.

    2011-08-01

    An emerging test and measurement standard called AXIe, AdvancedTCA extensions for Instrumentation, is expected to find wide acceptance within the Physics community as it offers many benefits to applications including shock, plasma, particle and nuclear physics. It is expected that many COTS (commercial off-the-shelf) signal conditioning, acquisition and processing modules will become available from a range of different suppliers. AXIe uses AdvancedTCA® as its basis, but then levers test and measurement industry standards such as PXI, IVI, and LXI to facilitate cooperation and plug-and-play interoperability between COTS instrument suppliers. AXIe's large board footprint and power allows high density in a 19" rack, enabling the development of high-performance signal conditioning, analog-to-digital conversion, and data processing, while offering channel count scalability inherent in modular systems. Synchronization between modules is flexible and provided by two triggering structures: a parallel trigger bus, and radially-distributed, time-matched point-to-point trigger lines. Inter-module communication is also provided with an adjacent module local bus allowing data transfer to 600 Gbits/s in each direction, for example between a front-end digitizer and DSP. AXIe allows embedding high performance computing and a range of COTS AdvancedTCA® computer blades are currently available that provide low cost alternatives to the development of custom signal processing modules. The availability of both LAN and PCI Express allow interconnection between modules, as well as industry-standard high-performance data paths to external host computer systems. AXIe delivers a powerful environment for custom module devel opment. As in the case of VXIbus and PXI before it, commercial development kits are expected to be available. This paper will give an overview of the architectural elements of AXIe 1.0, the compatibility model with AdvancedTCA, and signal acquisition performance of many of the AXIe structures.

  10. When everything is not everywhere but species evolve: an alternative method to model adaptive properties of marine ecosystems

    PubMed Central

    Sauterey, Boris; Ward, Ben A.; Follows, Michael J.; Bowler, Chris; Claessen, David

    2015-01-01

    The functional and taxonomic biogeography of marine microbial systems reflects the current state of an evolving system. Current models of marine microbial systems and biogeochemical cycles do not reflect this fundamental organizing principle. Here, we investigate the evolutionary adaptive potential of marine microbial systems under environmental change and introduce explicit Darwinian adaptation into an ocean modelling framework, simulating evolving phytoplankton communities in space and time. To this end, we adopt tools from adaptive dynamics theory, evaluating the fitness of invading mutants over annual timescales, replacing the resident if a fitter mutant arises. Using the evolutionary framework, we examine how community assembly, specifically the emergence of phytoplankton cell size diversity, reflects the combined effects of bottom-up and top-down controls. When compared with a species-selection approach, based on the paradigm that “Everything is everywhere, but the environment selects”, we show that (i) the selected optimal trait values are similar; (ii) the patterns emerging from the adaptive model are more robust, but (iii) the two methods lead to different predictions in terms of emergent diversity. We demonstrate that explicitly evolutionary approaches to modelling marine microbial populations and functionality are feasible and practical in time-varying, space-resolving settings and provide a new tool for exploring evolutionary interactions on a range of timescales in the ocean. PMID:25852217

  11. When everything is not everywhere but species evolve: an alternative method to model adaptive properties of marine ecosystems.

    PubMed

    Sauterey, Boris; Ward, Ben A; Follows, Michael J; Bowler, Chris; Claessen, David

    2015-01-01

    The functional and taxonomic biogeography of marine microbial systems reflects the current state of an evolving system. Current models of marine microbial systems and biogeochemical cycles do not reflect this fundamental organizing principle. Here, we investigate the evolutionary adaptive potential of marine microbial systems under environmental change and introduce explicit Darwinian adaptation into an ocean modelling framework, simulating evolving phytoplankton communities in space and time. To this end, we adopt tools from adaptive dynamics theory, evaluating the fitness of invading mutants over annual timescales, replacing the resident if a fitter mutant arises. Using the evolutionary framework, we examine how community assembly, specifically the emergence of phytoplankton cell size diversity, reflects the combined effects of bottom-up and top-down controls. When compared with a species-selection approach, based on the paradigm that "Everything is everywhere, but the environment selects", we show that (i) the selected optimal trait values are similar; (ii) the patterns emerging from the adaptive model are more robust, but (iii) the two methods lead to different predictions in terms of emergent diversity. We demonstrate that explicitly evolutionary approaches to modelling marine microbial populations and functionality are feasible and practical in time-varying, space-resolving settings and provide a new tool for exploring evolutionary interactions on a range of timescales in the ocean.

  12. Acoustic Observation of Living Organisms Reveals the Upper Limit of the Oxygen Minimum Zone

    PubMed Central

    Bertrand, Arnaud; Ballón, Michael; Chaigneau, Alexis

    2010-01-01

    Background Oxygen minimum zones (OMZs) are expanding in the World Ocean as a result of climate change and direct anthropogenic influence. OMZ expansion greatly affects biogeochemical processes and marine life, especially by constraining the vertical habitat of most marine organisms. Currently, monitoring the variability of the upper limit of the OMZs relies on time intensive sampling protocols, causing poor spatial resolution. Methodology/Principal Findings Using routine underwater acoustic observations of the vertical distribution of marine organisms, we propose a new method that allows determination of the upper limit of the OMZ with a high precision. Applied in the eastern South-Pacific, this original sampling technique provides high-resolution information on the depth of the upper OMZ allowing documentation of mesoscale and submesoscale features (e.g., eddies and filaments) that structure the upper ocean and the marine ecosystems. We also use this information to estimate the habitable volume for the world's most exploited fish, the Peruvian anchovy (Engraulis ringens). Conclusions/Significance This opportunistic method could be implemented on any vessel geared with multi-frequency echosounders to perform comprehensive high-resolution monitoring of the upper limit of the OMZ. Our approach is a novel way of studying the impact of physical processes on marine life and extracting valid information about the pelagic habitat and its spatial structure, a crucial aspect of Ecosystem-based Fisheries Management in the current context of climate change. PMID:20442791

  13. Phosphorus physiological ecology and molecular mechanisms in marine phytoplankton.

    PubMed

    Lin, Senjie; Litaker, Richard Wayne; Sunda, William G

    2016-02-01

    Phosphorus (P) is an essential nutrient for marine phytoplankton and indeed all life forms. Current data show that P availability is growth-limiting in certain marine systems and can impact algal species composition. Available P occurs in marine waters as dissolved inorganic phosphate (primarily orthophosphate [Pi]) or as a myriad of dissolved organic phosphorus (DOP) compounds. Despite numerous studies on P physiology and ecology and increasing research on genomics in marine phytoplankton, there have been few attempts to synthesize information from these different disciplines. This paper is aimed to integrate the physiological and molecular information on the acquisition, utilization, and storage of P in marine phytoplankton and the strategies used by these organisms to acclimate and adapt to variations in P availability. Where applicable, we attempt to identify gaps in our current knowledge that warrant further research and examine possible metabolic pathways that might occur in phytoplankton from well-studied bacterial models. Physical and chemical limitations governing cellular P uptake are explored along with physiological and molecular mechanisms to adapt and acclimate to temporally and spatially varying P nutrient regimes. Topics covered include cellular Pi uptake and feedback regulation of uptake systems, enzymatic utilization of DOP, P acquisition by phagotrophy, P-limitation of phytoplankton growth in oceanic and coastal waters, and the role of P-limitation in regulating cell size and toxin levels in phytoplankton. Finally, we examine the role of P and other nutrients in the transition of phytoplankton communities from early succession species (diatoms) to late succession ones (e.g., dinoflagellates and haptophytes). © 2015 Phycological Society of America.

  14. Analysis of Successful Strategy to Develop Sustainable Marine Ecotourism in Gili Bawean Island, Gresik, East Java

    NASA Astrophysics Data System (ADS)

    Wardani, M. P.; Fahrudin, A.; Yulianda, F.

    2017-10-01

    The sustainability of resources and marine ecotourism in Gili Bawean Island is still developing to the current day. The management is conducted individualistically and is currently far away from being integrated and sustainable. It is important that stakeholders understand the island’s condition and the urgency of coastal resources, to determine collective action, which leads to sustainable ecotourism on the island. This research aimed to discover stakeholders’ involvement in determining key variables and formulate a strategy of marine ecotourism development based on possible future scenarios in Gili Bawean Island, Gresik Regency, East Java. The field study was done through an expert meeting of stakeholder representatives on March-April 2017. The data was analyzed using Participatory Prospective Analysis (PPA), a comprehensive and quick framework, which was designed to demand requests in structural anticipation and exploration and also to focus on interaction and consensus among stakeholders. The results of this research show that five main variables should be emphasized in developing marine ecotourism on the island, including tourist activities, institutions, and economic activities, as well as the quality of human and natural resources. Counting heavily on those variables, it is hoped to create an integrated marine ecotourism development. Coordination among stakeholders can be declared successful when the tourist objects are managed better, and the quality of tourist destinations and the number of tourist visits increase noticeably. Good governance of marine ecotourism contributes to increments in tourist amenities, boosts the welfare of local communities, and secures sustainability of local natural resources.

  15. Evidence of Late Pliocene-Early Pleistocene marine environments in the deep subsurface of the Lihue Basin, Kauai, Hawaii

    USGS Publications Warehouse

    Izuka, S.K.; Resig, J.M.

    2008-01-01

    Cuttings recovered from two deep exploratory wells in the Lihue Basin, Kauai, Hawaii, include fossiliferous marine deposits that offer an uncommon opportunity to study paleoenvironments from the deep subsurface in Hawaii and interpret the paleogeography and geologic history of Kauai. These deposits indicate that two marine incursions gave rise to protected shallow-water, low-energy embayments in the southern part of the Lihue Basin in the late Pliocene-early Pleistocene. During the first marine incursion, the embayment was initially zoned, with a variable-salinity environment nearshore and a normal-marine reef environment offshore. The offshore reef environment eventually evolved to a nearshore, variable-salinity environment as the outer part of the embayment shallowed. During the second marine incursion, the embayment had normal-marine to hypersaline conditions, which constitute a significant departure from the variable-salinity environment present during the first marine incursion. Large streams draining the southern Lihue Basin are a likely source of the freshwater that caused the salinity fluctuations evident in the fossils from the first marine incursion. Subsequent volcanic eruptions produced lava flows that buried the embayment and probably diverted much of the stream flow in the southern Lihue Basin northward, to its present point of discharge north of Kalepa Ridge. As a result, the embayment that formed during the second marine incursion received less freshwater, and a normal-marine to hypersaline environment developed. The shallow-water marine deposits, currently buried between 86 m and 185 m below present sea level, have implications for regional tectonics and global eustasy. Copyright ?? 2008, SEPM (Society for Sedimentary Geology).

  16. Marine medicinal glycomics

    PubMed Central

    Pomin, Vitor H.

    2014-01-01

    Glycomics is an international initiative aimed to understand the structure and function of the glycans from a given type of cell, tissue, organism, kingdom or even environment, as found under certain conditions. Glycomics is one of the latest areas of intense biological research. Glycans of marine sources are unique in terms of structure and function. They differ considerably from those of terrestrial origin. This review discusses the most known marine glycans of potential therapeutic properties. They are chitin, chitosan, and sulfated polysaccharides named glycosaminoglycans, sulfated fucans, and sulfated galactans. Their medical actions are very broad. When certain structural requirements are found, these glycans can exhibit beneficial effects in inflammation, coagulation, thrombosis, cancer growth/metastasis, and vascular biology. Both structure and therapeutic mechanisms of action of these marine glycans are discussed here in straight context with the current glycomic age through a project suggestively named marine medicinal glycomics. PMID:24524028

  17. Upgrading Marine Ecosystem Restoration Using Ecological-Social Concepts.

    PubMed

    Abelson, Avigdor; Halpern, Benjamin S; Reed, Daniel C; Orth, Robert J; Kendrick, Gary A; Beck, Michael W; Belmaker, Jonathan; Krause, Gesche; Edgar, Graham J; Airoldi, Laura; Brokovich, Eran; France, Robert; Shashar, Nadav; de Blaeij, Arianne; Stambler, Noga; Salameh, Pierre; Shechter, Mordechai; Nelson, Peter A

    2016-02-01

    Conservation and environmental management are principal countermeasures to the degradation of marine ecosystems and their services. However, in many cases, current practices are insufficient to reverse ecosystem declines. We suggest that restoration ecology , the science underlying the concepts and tools needed to restore ecosystems, must be recognized as an integral element for marine conservation and environmental management. Marine restoration ecology is a young scientific discipline, often with gaps between its application and the supporting science. Bridging these gaps is essential to using restoration as an effective management tool and reversing the decline of marine ecosystems and their services. Ecological restoration should address objectives that include improved ecosystem services, and it therefore should encompass social-ecological elements rather than focusing solely on ecological parameters. We recommend using existing management frameworks to identify clear restoration targets, to apply quantitative tools for assessment, and to make the re-establishment of ecosystem services a criterion for success.

  18. Marine Aerosols and Clouds.

    PubMed

    Brooks, Sarah D; Thornton, Daniel C O

    2018-01-03

    The role of marine bioaerosols in cloud formation and climate is currently so uncertain that even the sign of the climate forcing is unclear. Marine aerosols form through direct emissions and through the conversion of gas-phase emissions to aerosols in the atmosphere. The composition and size of aerosols determine how effective they are in catalyzing the formation of water droplets and ice crystals in clouds by acting as cloud condensation nuclei and ice nucleating particles, respectively. Marine organic aerosols may be sourced both from recent regional phytoplankton blooms that add labile organic matter to the surface ocean and from long-term global processes, such as the upwelling of old refractory dissolved organic matter from the deep ocean. Understanding the formation of marine aerosols and their propensity to catalyze cloud formation processes are challenges that must be addressed given the major uncertainties associated with aerosols in climate models.

  19. Plate tectonics drive tropical reef biodiversity dynamics

    PubMed Central

    Leprieur, Fabien; Descombes, Patrice; Gaboriau, Théo; Cowman, Peter F.; Parravicini, Valeriano; Kulbicki, Michel; Melián, Carlos J.; de Santana, Charles N.; Heine, Christian; Mouillot, David; Bellwood, David R.; Pellissier, Loïc

    2016-01-01

    The Cretaceous breakup of Gondwana strongly modified the global distribution of shallow tropical seas reshaping the geographic configuration of marine basins. However, the links between tropical reef availability, plate tectonic processes and marine biodiversity distribution patterns are still unknown. Here, we show that a spatial diversification model constrained by absolute plate motions for the past 140 million years predicts the emergence and movement of diversity hotspots on tropical reefs. The spatial dynamics of tropical reefs explains marine fauna diversification in the Tethyan Ocean during the Cretaceous and early Cenozoic, and identifies an eastward movement of ancestral marine lineages towards the Indo-Australian Archipelago in the Miocene. A mechanistic model based only on habitat-driven diversification and dispersal yields realistic predictions of current biodiversity patterns for both corals and fishes. As in terrestrial systems, we demonstrate that plate tectonics played a major role in driving tropical marine shallow reef biodiversity dynamics. PMID:27151103

  20. Plate tectonics drive tropical reef biodiversity dynamics.

    PubMed

    Leprieur, Fabien; Descombes, Patrice; Gaboriau, Théo; Cowman, Peter F; Parravicini, Valeriano; Kulbicki, Michel; Melián, Carlos J; de Santana, Charles N; Heine, Christian; Mouillot, David; Bellwood, David R; Pellissier, Loïc

    2016-05-06

    The Cretaceous breakup of Gondwana strongly modified the global distribution of shallow tropical seas reshaping the geographic configuration of marine basins. However, the links between tropical reef availability, plate tectonic processes and marine biodiversity distribution patterns are still unknown. Here, we show that a spatial diversification model constrained by absolute plate motions for the past 140 million years predicts the emergence and movement of diversity hotspots on tropical reefs. The spatial dynamics of tropical reefs explains marine fauna diversification in the Tethyan Ocean during the Cretaceous and early Cenozoic, and identifies an eastward movement of ancestral marine lineages towards the Indo-Australian Archipelago in the Miocene. A mechanistic model based only on habitat-driven diversification and dispersal yields realistic predictions of current biodiversity patterns for both corals and fishes. As in terrestrial systems, we demonstrate that plate tectonics played a major role in driving tropical marine shallow reef biodiversity dynamics.

  1. Upgrading Marine Ecosystem Restoration Using Ecological‐Social Concepts

    PubMed Central

    Abelson, Avigdor; Halpern, Benjamin S.; Reed, Daniel C.; Orth, Robert J.; Kendrick, Gary A.; Beck, Michael W.; Belmaker, Jonathan; Krause, Gesche; Edgar, Graham J.; Airoldi, Laura; Brokovich, Eran; France, Robert; Shashar, Nadav; de Blaeij, Arianne; Stambler, Noga; Salameh, Pierre; Shechter, Mordechai; Nelson, Peter A.

    2015-01-01

    Conservation and environmental management are principal countermeasures to the degradation of marine ecosystems and their services. However, in many cases, current practices are insufficient to reverse ecosystem declines. We suggest that restoration ecology, the science underlying the concepts and tools needed to restore ecosystems, must be recognized as an integral element for marine conservation and environmental management. Marine restoration ecology is a young scientific discipline, often with gaps between its application and the supporting science. Bridging these gaps is essential to using restoration as an effective management tool and reversing the decline of marine ecosystems and their services. Ecological restoration should address objectives that include improved ecosystem services, and it therefore should encompass social–ecological elements rather than focusing solely on ecological parameters. We recommend using existing management frameworks to identify clear restoration targets, to apply quantitative tools for assessment, and to make the re-establishment of ecosystem services a criterion for success. PMID:26977115

  2. Submarine paleoseismology based on turbidite records.

    PubMed

    Goldfinger, Chris

    2011-01-01

    Many of the largest earthquakes are generated at subduction zones or other plate boundary fault systems near enough to the coast that marine environments may record evidence of them. During and shortly after large earthquakes in the coastal and marine environments, a spectrum of evidence may be left behind, mirroring onshore paleoseismic evidence. Shaking or displacement of the seafloor can trigger processes such as turbidity currents, submarine landslides, tsunami (which may be recorded both onshore and offshore), and soft-sediment deformation. Marine sites may also share evidence of fault scarps, colluvial wedges, offset features, and liquefaction or fluid expulsion with their onshore counterparts. This article reviews the use of submarine turbidite deposits for paleoseismology, focuses on the dating and correlation techniques used to establish stratigraphic continuity of marine deposits, and outlines criteria for distinguishing earthquake deposits and the strategies used to acquire suitable samples and data for marine paleoseismology.

  3. Visualization of Microfloral Metabolism for Marine Waste Recycling

    PubMed Central

    Ogura, Tatsuki; Hoshino, Reona; Date, Yasuhiro; Kikuchi, Jun

    2016-01-01

    Marine biomass including fishery products are precious protein resources for human foods and are an alternative to livestock animals in order to reduce the virtual water problem. However, a large amount of marine waste can be generated from fishery products and it is not currently recycled. We evaluated the metabolism of digested marine waste using integrated analytical methods, under anaerobic conditions and the fertilization of abandoned agricultural soils. Dynamics of fish waste digestion revealed that samples of meat and bony parts had similar dynamics under anaerobic conditions in spite of large chemical variations in input marine wastes. Abandoned agricultural soils fertilized with fish waste accumulated some amino acids derived from fish waste, and accumulation of l-arginine and l-glutamine were higher in plant seedlings. Therefore, we have proposed an analytical method to visualize metabolic dynamics for recycling of fishery waste processes. PMID:26828528

  4. Inhibition of biofouling by marine microorganisms and their metabolites.

    PubMed

    Dobretsov, Sergey; Dahms, Hans-Uwe; Qian, Peri-Yuan

    2006-01-01

    Development of microbial biofilms and the recruitment of propagules on the surfaces of man-made structures in the marine environment cause serious problems for the navies and for marine industries around the world. Current antifouling technology is based on the application of toxic substances that can be harmful to the natural environment. For this reason and the global ban of tributyl tin (TBT), there is a need for the development of "environmentally-friendly" antifoulants. Marine microbes are promising potential sources of non-toxic or less-toxic antifouling compounds as they can produce substances that inhibit not only the attachment and/or growth of microorganisms but also the settlement of invertebrate larvae and macroalgal spores. However, so far only few antilarval settlement compounds have been isolated and identified from bacteria. In this review knowledge about antifouling compounds produced by marine bacteria and diatoms are summarised and evaluated and future research directions are highlighted.

  5. Sulfur oxidation to sulfate coupled with electron transfer to electrodes by Desulfuromonas strain TZ1

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

    Zhang, T; Bain, TS; Barlett, MA

    2014-01-02

    Microbial oxidation of elemental sulfur with an electrode serving as the electron acceptor is of interest because this may play an important role in the recovery of electrons from sulfidic wastes and for current production in marine benthic microbial fuel cells. Enrichments initiated with a marine sediment inoculum, with elemental sulfur as the electron donor and a positively poised (+300 mV versus Ag/AgCl) anode as the electron acceptor, yielded an anode biofilm with a diversity of micro-organisms, including Thiobacillus, Sulfurimonas, Pseudomonas, Clostridium and Desulfuromonas species. Further enrichment of the anode biofilm inoculum in medium with elemental sulfur as the electronmore » donor and Fe(III) oxide as the electron acceptor, followed by isolation in solidified sulfur/Fe(III) medium yielded a strain of Desulfuromonas, designated strain TZ1. Strain TZ1 effectively oxidized elemental sulfur to sulfate with an anode serving as the sole electron acceptor, at rates faster than Desulfobulbus propionicus, the only other organism in pure culture previously shown to oxidize S with current production. The abundance of Desulfuromonas species enriched on the anodes of marine benthic fuel cells has previously been interpreted as acetate oxidation driving current production, but the results presented here suggest that sulfur-driven current production is a likely alternative.« less

  6. Nitric oxide in the stress axis.

    PubMed

    López-Figueroa, M O; Day, H E; Akil, H; Watson, S J

    1998-10-01

    In recent years nitric oxide (NO) has emerged as a unique biological messenger. NO is a highly diffusible gas, synthesized from L-arginine by the enzyme nitric oxide synthase (NOS). Three unique subtypes of NOS have been described, each with a specific distribution profile in the brain and periphery. NOS subtype I is present, among other areas, in the hippocampus, hypothalamus, pituitary and adrenal gland. Together these structures form the limbic-hypothalamic-pituitary-adrenal (LHPA) or stress axis, activation of which is one of the defining features of a stress response. Evidence suggests that NO may modulate the release of the stress hormones ACTH and corticosterone, and NOS activity and transcription is increased in the LHPA axis following various stressful stimuli. Furthermore, following activation of the stress axis, glucocorticoids are thought to down-regulate the transcription and activity of NOS via a feedback mechanism. Taken together, current data indicate a role for NO in the regulation of the LHPA axis, although at present this role is not well defined. It has been suggested that NO may act as a cellular communicator in plasticity and development, to facilitate the activation or the release of other neurotransmitters, to mediate immune responses, and/or as a vasodilator in the regulation of blood flow. In the following review we summarize some of the latest insights into the function of NO, with special attention to its relationship with the LHPA axis.

  7. Electron transport fluxes in potato plateau regime

    NASA Astrophysics Data System (ADS)

    Shaing, K. C.; Hazeltine, R. D.

    1997-12-01

    Electron transport fluxes in the potato plateau regime are calculated from the solutions of the drift kinetic equation and fluid equations. It is found that the bootstrap current density remains finite in the region close to the magnetic axis, although it decreases with increasing collision frequency. This finite amount of the bootstrap current in the relatively collisional regime is important in modeling tokamak startup with 100% bootstrap current.

  8. 46 CFR 185.304 - Navigation underway.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... in order to prevent a casualty. Special attention should be paid to: (1) The current(s) velocity and...) Density of marine traffic; (5) Potential damage caused by own wake; (6) The danger of each closing visual...

  9. Posttraumatic stress mediates the relationship between childhood victimization and current mental health burden in newly incarcerated adults.

    PubMed

    Greene, Carolyn A; Ford, Julian D; Wakefield, Dorothy B; Barry, Lisa C

    2014-10-01

    The purpose of this study was to evaluate the interrelationship among childhood abuse and traumatic loss, posttraumatic stress symptoms (PTSS), and Axis I psychiatric disorders other than PTSD among newly incarcerated adults, and to test a proposed model in which the severity of PTSS mediates the relationship between childhood abuse/loss and adult psychiatric disorders. Four hundred sixty-five male and female inmates participated in a structured clinical research interview. Four types of interpersonal potentially traumatic experiences (physical abuse, sexual abuse, emotional abuse, and traumatic loss) were assessed for occurrence prior to the age of 18 years old. Current psychiatric disorders and PTSS were also assessed by structured interview. Negative binomial regression was used to evaluate the association between the cumulative number of types of childhood abuse/loss experienced and number of current Axis I disorders, and to test the mediation model. Approximately half of the sample (51%) experienced 1 or more types of childhood abuse/loss, and 30% of the sample had at least one psychiatric disorder other than PTSD. For both men and women, childhood physical abuse and childhood sexual abuse were independently associated with psychiatric morbidity, and an increasing number of types of childhood trauma experienced was associated with an increase in the number of current Axis I diagnoses. However, these associations were no longer statistically significant when severity of PTSS was added to the model, providing support for the proposed mediation model. Implications for secondary prevention services for at-risk inmates are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Operations and support cost modeling of conceptual space vehicles

    NASA Technical Reports Server (NTRS)

    Ebeling, Charles

    1994-01-01

    The University of Dayton is pleased to submit this annual report to the National Aeronautics and Space Administration (NASA) Langley Research Center which documents the development of an operations and support (O&S) cost model as part of a larger life cycle cost (LCC) structure. It is intended for use during the conceptual design of new launch vehicles and spacecraft. This research is being conducted under NASA Research Grant NAG-1-1327. This research effort changes the focus from that of the first two years in which a reliability and maintainability model was developed to the initial development of an operations and support life cycle cost model. Cost categories were initially patterned after NASA's three axis work breakdown structure consisting of a configuration axis (vehicle), a function axis, and a cost axis. A revised cost element structure (CES), which is currently under study by NASA, was used to established the basic cost elements used in the model. While the focus of the effort was on operations and maintenance costs and other recurring costs, the computerized model allowed for other cost categories such as RDT&E and production costs to be addressed. Secondary tasks performed concurrent with the development of the costing model included support and upgrades to the reliability and maintainability (R&M) model. The primary result of the current research has been a methodology and a computer implementation of the methodology to provide for timely operations and support cost analysis during the conceptual design activities.

  11. Phase dynamics of oscillating magnetizations coupled via spin pumping

    NASA Astrophysics Data System (ADS)

    Taniguchi, Tomohiro

    2018-05-01

    A theoretical formalism is developed to simultaneously solve equation of motion of the magnetizations in two ferromagnets and the spin-pumping induced spin transport equation. Based on the formalism, a coupled motion of the magnetizations in a self-oscillation state is studied. The spin pumping is found to induce an in-phase synchronization of the magnetizations for the oscillation around the easy axis. For an out-of-plane self-oscillation around the hard axis, on the other hand, the spin pumping leads to an in-phase synchronization in a small current region, whereas an antiphase synchronization is excited in a large current region. An analytical theory based on the phase equation reveals that the phase difference between the magnetizations in a steady state depends on the oscillation direction, clockwise or counterclockwise, of the magnetizations.

  12. Influence of the spatially inhomogeneous gap distribution on the quasiparticle current in c-axis junctions involving d-wave superconductors with charge density waves.

    PubMed

    Ekino, T; Gabovich, A M; Suan Li, Mai; Szymczak, H; Voitenko, A I

    2016-11-09

    The quasiparticle tunnel current J(V) between the superconducting ab-planes along the c-axis and the corresponding conductance [Formula: see text] were calculated for symmetric junctions composed of disordered d-wave layered superconductors partially gapped by charge density waves (CDWs). Here, V is the voltage. Both the checkerboard and unidirectional CDWs were considered. It was shown that the spatial spread of the CDW-pairing strength substantially smears the peculiarities of G(V) appropriate to uniform superconductors. The resulting curves G(V) become very similar to those observed for a number of cuprates in intrinsic junctions, e.g. mesas. In particular, the influence of CDWs may explain the peak-dip-hump structures frequently found for high-T c oxides.

  13. Development of a two-dimensional skin friction balance nulling circuit using multivariable control theory

    NASA Technical Reports Server (NTRS)

    Tripp, John S.; Patek, Stephen D.

    1988-01-01

    Measurement of planar skin friction forces in aerodynamic testing currently requires installation of two perpendicularly mounted, single-axis balances; consequently, force components must be sensed at two distinct locations. A two-axis instrument developed at the Langley Research Center to overcome this disadvantage allows measurement of a two-dimensional force at one location. This paper describes a feedback-controlled nulling circuit developed for the NASA two-axis balance which, without external compensation, is inherently unstable because of its low friction mechanical design. Linear multivariable control theory is applied to an experimentally validated mathematical model of the balance to synthesize a state-variable feedback control law. Pole placement techniques and computer simulation studies are employed to select eigenvalues which provide ideal transient response with decoupled sensing dynamics.

  14. 75 FR 20344 - Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Rocket Launches from...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-19

    ... (LOA) has been issued to the Alaska Aerospace Corporation (AAC, formerly known as the Alaska Aerospace... scheduled prior to expiration of the current LOA. As such, the most recent reports concerning activity and... ambient levels for one minute thirty three seconds with an SEL of 89.6 dBA. The one-second broadband peak...

  15. Directory of Personnel in Research, Technology, Education, Administration and Management. Development Activities in the Marine Environment of the Coastal Plains Region.

    ERIC Educational Resources Information Center

    Mecca, Christyna E.

    Listed in this directory are individuals concerned currently with marine activities on the coasts of North Carolina, South Carolina, and Georgia, and the adjacent offshore area, known administratively as the Coastal Plains Region. The categories for the listings include educational institutions, state and county agencies, and federal agencies. The…

  16. 78 FR 8111 - Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Space Vehicle and Test...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-05

    ... hereby given that a letter of authorization (LOA) has been issued to the 30th Space Wing, U.S. Air Force...). Currently, six space launch vehicle programs use VAFB to launch satellites into polar orbit: Delta II; Taurus; Atlas V; Delta IV; Falcon; and Minotaur. Also a variety of small missiles, several types of...

  17. 77 FR 6086 - Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Space Vehicle and Test...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-07

    ... hereby given that a letter of authorization (LOA) has been issued to the 30th Space Wing, U.S. Air Force...). Currently, six space launch vehicle programs use VAFB to launch satellites into polar orbit: Delta II; Taurus; Atlas V; Delta IV; Falcon; and Minotaur. Also a variety of small missiles, several types of...

  18. Use of Nanoscale Emulsified Zero-valent Iron to Treat a Chlorinated Solvent Source Zone at Site 45, Marine Corp Recruit Depot, Parris Island, South Carolina

    EPA Science Inventory

    This document summarizes the research activities currently underway at the Solid Waste Management Unit 45 (Site 45), Marine Corps Recruit Depot, Parris Island, South Carolina. A pilot field test was initiated in 2005 at this site to evaluate the effectiveness of nanoscale emulsif...

  19. Cadherin Domains in the Polysaccharide-Degrading Marine Bacterium Saccharophagus degradans 2-40 Are Carbohydrate-Binding Modules▿

    PubMed Central

    Fraiberg, Milana; Borovok, Ilya; Bayer, Edward A.; Weiner, Ronald M.; Lamed, Raphael

    2011-01-01

    The complex polysaccharide-degrading marine bacterium Saccharophagus degradans strain 2-40 produces putative proteins that contain numerous cadherin and cadherin-like domains involved in intercellular contact interactions. The current study reveals that both domain types exhibit reversible calcium-dependent binding to different complex polysaccharides which serve as growth substrates for the bacterium. PMID:21036994

  20. Seabird Conservation Planning in the Pacific Region

    Treesearch

    Kyra L. Mills; Maura Naughton; Gregg Elliott

    2005-01-01

    The North Pacific is a highly productive marine area, sustaining millions of resident and migratory marine birds. These birds are faced with a variety of threats, both on land, where they breed and roost, and at sea, where they forage for food. Several seabird conservation plans are currently underway in this region. The U. S. Fish and Wildlife Service (USFWS) Pacific...

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