Science.gov

Sample records for fast plasma shutdowns

  1. The behavior of runaway current in massive gas injection fast shutdown plasmas in J-TEXT

    NASA Astrophysics Data System (ADS)

    Chen, Z. Y.; Huang, D. W.; Luo, Y. H.; Tang, Y.; Dong, Y. B.; Zeng, L.; Tong, R. H.; Wang, S. Y.; Wei, Y. N.; Wang, X. H.; Jian, X.; Li, J. C.; Zhang, X. Q.; Rao, B.; Yan, W.; Ma, T. K.; Hu, Q. M.; Yang, Z. J.; Gao, L.; Ding, Y. H.; Wang, Z. J.; Zhang, M.; Zhuang, G.; Pan, Y.; Jiang, Z. H.; J-TEXT Team

    2016-11-01

    Runaway currents following disruptions have an important effect on the first wall in current tokamaks and will be more severe in next generation tokamaks. The behavior of runaway currents in massive gas injection (MGI) induced disruptions have been investigated in the J-TEXT tokamak. The cold front induced by the gas jet penetrates helically along field lines, preferentially toward the high field side and stops at a location near the q  =  2 surface before the disruption. When the cold front reaches the q  =  2 surface it initiates magnetohydrodynamic activities and results in disruption. It is found that the MGI of He or Ne results in runaway free shutdown in a large range of gas injections. Mixture injection of He and Ar (90% He and 10%Ar) consistently results in runaway free shutdown. A moderate amount of Ar injection could produce significant runaway current. The maximum runaway energy in the runaway plateau is estimated using a simplified model which neglects the drag forces and other energy loss mechanisms. The maximum runaway energy increases with decreasing runaway current. Imaging of the runaway beam using a soft x-ray array during the runaway current plateau indicates that the runaway beam is located in the center of the plasma. Resonant magnetic perturbation (RMP) is applied to reduce the runaway current successfully during the disruption phase in a small scale tokamak, J-TEXT. When the runaway current builds up, the application of RMP cannot decouple the runaway beam due to the lower sensitivity of the energetic runaway electrons to the magnetic perturbation.

  2. Fast Plasma Shutdowns Obtained With Massive Hydrogenic, Noble and Mixed-Gas Injection in DIII-D

    SciTech Connect

    Wesley, J; Hollmann, E; Jernigan, T; Van Zeeland, M; Baylor, L; Boedo, J; Combs, S; Evans, T; Groth, M; Humphreys, D; Hyatt, A; Izzo, V; James, A; Moyer, R; Parks, P; Rudakov, D; Strait, E; Wu, W; Yu, J

    2008-10-14

    Massive gas injection (MGI) experiments with H{sub 2}, D{sub 2}, He, Ne and Ar and 'mixed' (H{sub 2} + Ar and D{sub 2} + Ne) gases injected into 'ITER-similar' 1.3-MA H-mode plasmas are described. Gas species, injected quantity Q, delivery time, t{sub inj}, rate-of-rise and intrinsic and added impurities are found to affect the attributes and 'disruption mitigation' efficacies of the resulting fast plasma shutdowns. With sufficient Q and t{sub inj} < {approx}2 ms, all species provide fast (within {le} {approx}3 ms), more-or-less uniform radiative dissipation of the 0.7-MJ plasma thermal energy and fast but benign current decays with reduced vacuum vessel vertical force impulse. With pure and mixed low-Z gases, free-electron densities up to 2 x 10{sup 21} m{sup -3} are obtained. While these densities are high relative to normal tokamak densities, they are still an order of magnitude smaller than the densities required for unconditional mitigation of the runaway electron avalanche process. Key information relevant to the design of effective MGI systems for larger tokamaks and ITER has been obtained and the collective species and Q-variation data provides a rich basis for validation of emerging 2D + t MHD/transport/radiation models.

  3. Measurements of Impurity and Heat Dynamics During Noble Gas Jet-Initiated Fast Plasma Shutdown for Disruption Mitigation in DIII-D

    SciTech Connect

    Hollmann, E M; Jernigan, T C; Groth, M; Whyte, D G; Gray, D S; Brennan, D P; Brooks, N H; Evans, T E; Humphreys, D A; Lasnier, C J; Moyer, R A; McClean, A; Parks, P B; Rozhansky, V; Rudakov, D L; Strait, E J; West, W P

    2004-12-01

    Impurity deposition and mixing during gas jet-initiated plasma shutdown is studied using a rapid ({approx}2 ms), massive ({approx}10{sup 22} particles) injection of neon or argon into stationary DIII-D H-mode discharges. Fast-gated camera images indicate that the bulk of the jet neutrals do not penetrate far into the plasma pedestal. Nevertheless, high ({approx}90%) thermal quench radiated power fractions are achieved; this appears to be facilitated through a combination of fast ion mixing and fast heat transport, both driven by large-scale MHD activity. Also, runaway electron suppression is achieved for sufficiently high gas jet pressures. These experiments suggest that massive gas injection could be viable for disruption mitigation in future tokamaks even if core penetration of jet neutrals is not achieved.

  4. Fast Thermal Shutdown of Tokamak Discharges Without Runaway Electron Avalanching

    SciTech Connect

    Bakhtiari, M.; Yoshino, R.; Nishida, Y

    2002-03-15

    The possibility of using massive quantities of injected deuterium with and without additional admixture of lesser quantities of higher-Z impurities to effect fast thermal shutdown of a tokamak discharge without causing runaway electron avalanching is systematically studied. It is found that various combinations of deuterium alone and deuterium with impurities (helium, nitrogen, argon, and krypton) can provide acceptable runaway-free thermal shutdown. The admixture of impurities cited reduces the quantity of deuterium needed and also reduces the radiative cooling time needed for the plasma to reach final thermal equilibrium, where radiation losses balance ohmic input. In contrast, the addition of neon does not appreciably reduce deuterium quantity or promote faster cooling. This difference relative to the other impurity studies can be understood from the radiation versus plasma temperature characteristics for neon.

  5. SSME technology test bed fast shutdown assessment

    NASA Technical Reports Server (NTRS)

    Liebman, A.; Vilja, J. O.

    1988-01-01

    The fastest practical shutdown sequence for the Technology Test Bed Engine is developed. A sequence is defined and key issues addressed. The conclusion of the study is that a fastest shutdown sequence within the existing SSME design capability is practical and can cut oxidizer consumption by 50 percent. However, the revised sequence would not have prevented any of the prior experienced SSME incidents and would introduce development risk to the program.

  6. The Fast Flux Test Facility shutdown program plan

    SciTech Connect

    Guttenberg, S.; Jones, D.H.; Midgett, J.C.; Nielsen, D.L.

    1995-01-01

    The Fast Flux Test Facility (FFTF) is a 400 MWt sodium-cooled research reactor owned by the US Department of Energy (DOE) and operated by the Westinghouse Hanford Company (WHC) on the Hanford Site in southeastern Washington State. The decision was made by the DOE in December, 1993, to initiate shutdown of the FFTF. This paper describes the FFTF Transition Project Plan (1) (formerly the FFTF Shutdown Program Plan) which provides the strategy, major elements, and project baseline for transitioning the FFTF to an industrially and radiologically safe shutdown condition. The Plan, and its resource loaded schedule, indicate this transition can be achieved in a period of six to seven years at a cost of approximately $359 million. The transition activities include reactor defueling, fuel offload to dry cask storage, sodium drain and reaction, management of sodium residuals, shutdown of auxiliary systems, and preparation of appropriate environmental and regulatory documentation. Completion of these activities will involve resolution of many challenging and unique issues associated with shutdown of a large sodium reactor facility. At the conclusion of these activities, the FFTF will be in a safe condition for turnover to the Hanford Site Environmental Restoration Contractor for a long term surveillance and maintenance phase and decommissioning.

  7. A fast shutdown system for SRS (Savannah River Site) reactors

    SciTech Connect

    Baumann, N.P.

    1990-01-01

    Power has been sharply reduced at Savannah River Site (SRS) reactors in large part to ensure that no bulk boiling occurs during hypothesized loss of coolant accidents. A fast shutdown system is essential to regain much of this lost power. Computations and experiments indicate that a He-3 injection system will serve this function. Instrumented tests of a full system are planned for early 1991 for one of the SRS reactors. 4 refs., 7 figs., 1 tab.

  8. Impact of the Digital Coil Protection System and Plasma Shutdown Handler on NSTX-U Operations

    NASA Astrophysics Data System (ADS)

    Gerhardt, Stefan; Battaglia, D.; Boyer, M.; Erickson, K.; Mueller, D.; Myers, C.; Mueller, D.; Sabbagh, S. A.

    2016-10-01

    In order to prevent excessive forces on the NSTX-U vessel and coils, a digital coil protection system (DCPS) has been implemented. This system computes approximately 400 different forces/torques/stresses, and terminates the discharge if limits on those quantities are exceeded. It is desirable, however, to prevent these coil system trips from ever happening. Given that many of these limits would be reached during transients associated with disruptions, as ``discharge shutdown handler'' was coded in the plasma control system to automatically control the plasma shutdown. This is a state machine with five states, and a set of rules for transitioning between states. The first use of these systems during plasma operations on NSTX-U will be described, with a focus on operational experiences and directions for future improvements. Work Supported by U.S.D.O.E. Contract No. DE-AC02-09CH11466.

  9. Experimental investigation of a new method for advanced fast reactor shutdown cooling

    NASA Astrophysics Data System (ADS)

    Pakholkov, V. V.; Kandaurov, A. A.; Potseluev, A. I.; Rogozhkin, S. A.; Sergeev, D. A.; Troitskaya, Yu. I.; Shepelev, S. F.

    2017-07-01

    We consider a new method for fast reactor shutdown cooling using a decay heat removal system (DHRS) with a check valve. In this method, a coolant from the decay heat exchanger (DHX) immersed into the reactor upper plenum is supplied to the high-pressure plenum and, then, inside the fuel subassemblies (SAs). A check valve installed at the DHX outlet opens by the force of gravity after primary pumps (PP-1) are shut down. Experimental studies of the new and alternative methods of shutdown cooling were performed at the TISEY test facility at OKBM. The velocity fields in the upper plenum of the reactor model were obtained using the optical particle image velocimetry developed at the Institute of Applied Physics (Russian Academy of Sciences). The study considers the process of development of natural circulation in the reactor and the DHRS models and the corresponding evolution of the temperature and velocity fields. A considerable influence of the valve position in the displacer of the primary pump on the natural circulation of water in the reactor through the DHX was discovered (in some modes, circulation reversal through the DHX was obtained). Alternative DHRS designs without a shell at the DHX outlet with open and closed check valve are also studied. For an open check valve, in spite of the absence of a shell, part of the flow is supplied through the DHX pipeline and then inside the SA simulators. When simulating power modes of the reactor operation, temperature stratification of the liquid was observed, which increased in the cooling mode via the DHRS. These data qualitatively agree with the results of tests at BN-600 and BN-800 reactors.

  10. Fast shut-down protection system for radio frequency breakdown and multipactor testing.

    PubMed

    Graves, T P; Hanson, P; Michaelson, J M; Farkas, A D; Hubble, A A

    2014-02-01

    Radio frequency (RF) breakdown such as multipactor or ionization breakdown is a device-limiting phenomenon for on-orbit spacecraft used for communication, navigation, or other RF payloads. Ground testing is therefore part of the qualification process for all high power components used in these space systems. This paper illustrates a shut-down protection system to be incorporated into multipactor/ionization breakdown ground testing for susceptible RF devices. This 8 channel system allows simultaneous use of different diagnostic classes and different noise floors. With initiation of a breakdown event, diagnostic signals increase above a user-specified level, which then opens an RF switch to eliminate RF power from the high power amplifier. Examples of this system in use are shown for a typical setup, illustrating the reproducibility of breakdown threshold voltages and the lack of multipactor conditioning. This system can also be utilized to prevent excessive damage to RF components in tests with sensitive or flight hardware.

  11. Fast pulse nonthermal plasma reactor

    DOEpatents

    Rosocha, Louis A.

    2005-06-14

    A fast pulsed nonthermal plasma reactor includes a discharge cell and a charging assembly electrically connected thereto. The charging assembly provides plural high voltage pulses to the discharge cell. Each pulse has a rise time between one and ten nanoseconds and a duration of three to twenty nanoseconds. The pulses create nonthermal plasma discharge within the discharge cell. Accordingly, the nonthermal plasma discharge can be used to remove pollutants from gases or break the gases into smaller molecules so that they can be more efficiently combusted.

  12. A study of passive safety features by utilizing intra-subassembly-equipped self-actuated shutdown mechanism for future large fast breeder reactors

    SciTech Connect

    Uto, N.; Niwa, H.; Ieda, Y.; Satoh, K.

    1996-08-01

    Passive prevention of core disruptive accidents (CDAs) is desired in terms of enhancement of safety for future fast breeder reactors. In addition, mitigation of CDA`s consequences should be required because mitigation measures have a potential of applying to all accidents, while prevention measures are prepared for specific accident initiators. In this paper, the Intra-Subassembly-equipped Self-Actuated Shutdown System (IS-SASS) , which is considered effective on passive prevention and mitigation of CDAs, is described. The IS-SASS is introduced in a fuel subassembly and consists of absorber materials at the top of the active core and an inner duct through which molten fuel can be excluded out of the core. The determination of the appropriate number of the IS-SASS units, their arrangement in the core and their suitable structure are found to be suited to prevention and mitigation of CDAs for liquid metal-cooled large fast breeder reactors.

  13. Plasma Acetone Metabolism in the Fasting Human

    PubMed Central

    Reichard, G. A.; Haff, A. C.; Skutches, C. L.; Paul, P.; Holroyde, C. P.; Owen, O. E.

    1979-01-01

    The metabolism of acetone was studied in lean and obese humans during starvation ketosis. Acetone concentrations in plasma, urine, and breath; and rates of endogenous production, elimination in breath and urine, and in vivo metabolism were determined. There was a direct relationship between plasma acetone turnover (20-77 μmol/m2 per min) and concentration (0.19-1.68 mM). Breath and urinary excretion of acetone accounted for a 2-30% of the endogenous production rate, and in vivo metabolism accounted for the remainder. Plasma acetone oxidation accounted for ≅60% of the production rate in 3-d fasted subjects and about 25% of the production rate in 21-d fasted subjects. About 1-2% of the total CO2 production was derived from plasma acetone oxidation and was not related to the plasma concentration or production rate. Radioactivity from [14C]acetone was not detected in plasma free fatty acids, acetoacetate, β-hydroxybutyrate, or other anionic compounds, but was present in plasma glucose, lipids, and proteins. If glucose synthesis from acetone is possible in humans, this process could account for 11% of the glucose production rate and 59% of the acetone production rate in 21-d fasted subjects. During maximum acetonemia, acetone production from acetoacetate could account for 37% of the anticipated acetoacetate production, which implies that a significant fraction of the latter compound does not undergo immediate terminal oxidation. PMID:438326

  14. Investigations on natural circulation in reactor models and shutdown heat removal systems for LMFBRs (liquid metal fast breeder reactors)

    SciTech Connect

    Hoffmann, H.; Weinberg, D.; Marten, K. ); Ieda, Yoshiaki )

    1989-11-01

    For sodium-cooled pool-type reactors, studies have been undertaken to remove the decay heat by natural convection alone, as in the case of failure of all power supplies. For this purpose, four immersion coolers (ICs), two each installed at a 180-deg circumferential position with respect to the others, are arranged within the reactor tank. They are connected with natural-drift air coolers through independent intermediate circuits. The primary sodium in the tank as well as the secondary sodium in the intermediate loop circulate by natural convection. The general functioning of this passive shutdown decay heat removal (DHR) system is demonstrated in 1:20 and 1:5 scale test models using water as a simulant fluid for sodium. The model design is based on the thermohydraulics similarity criteria. In the RAMONA three-dimensional 1:20 scale model, experiments were carried out to clarify the steady-state in-vessel thermohydraulics for different parameter combinations (core power, radial power distribution across the core, DHR by 2 or 4 ICs in operation, above-core structure geometry and position, different IC designs). For all mentioned parameters, temperatures and their fluctuations were measured and used to indicate isotherms and lines of identical temperature fluctuations. The flow patterns were observed visually. The experiments were recalculated by an updated version of the single-phase three-dimensional thermohydraulics code COMMIX.

  15. Fast wave evanescence in filamentary boundary plasmas

    SciTech Connect

    Myra, J. R.

    2014-02-15

    Radio frequency waves for heating and current drive of plasmas in tokamaks and other magnetic confinement devices must first traverse the scrape-off-layer (SOL) before they can be put to their intended use. The SOL plasma is strongly turbulent and intermittent in space and time. These turbulent properties of the SOL, which are not routinely taken into account in wave propagation codes, can have an important effect on the coupling of waves through an evanescent SOL or edge plasma region. The effective scale length for fast wave (FW) evanescence in the presence of short-scale field-aligned filamentary plasma turbulence is addressed in this paper. It is shown that although the FW wavelength or evanescent scale length is long compared with the dimensions of the turbulence, the FW does not simply average over the turbulent density; rather, the average is over the exponentiation rate. Implications for practical situations are discussed.

  16. Fast ion beam-plasma interaction system.

    PubMed

    Breun, R A; Ferron, J R

    1979-07-01

    A device has been constructed for the study of the interaction between a fast ion beam and a target plasma of separately controllable parameters. The beam of either hydrogen or helium ions has an energy of 1-4 keV and a total current of 0.5-2 A. The beam energy and beam current can be varied separately. The ion source plasma is created by a pulsed (0.2-10-ms pulse length) discharge in neutral gas at up to 3 x 10(-3) Torr. The neutrals are pulsed into the source chamber, allowing the neutral pressure in the target region to remain less than 5 x 10(-5) Torr at a 2-Hz repetition rate. The creation of the source plasma can be described by a simple set of equations which predict optimum source design parameters. The target plasma is also produced by a pulsed discharge. Between the target and source chambers the beam is neutralized by electrons drawn from a set of hot filaments. Currently under study is an unstable wave in a field-free plasma excited when the beam velocity is nearly equal to the target electron thermal velocity (v(beam) approximately 3.5 x 10(7) cm/s, Te = 0.5 eV).

  17. Laser–plasma interactions for fast ignition

    SciTech Connect

    Kemp, A. J.; Fiuza, F.; Debayle, A.; Johzaki, T.; Mori, W. B.; Patel, P. K.; Sentoku, Y.; Silva, L. O.

    2014-04-17

    In the electron-driven fast-ignition approach to inertial confinement fusion, petawatt laser pulses are required to generate MeV electrons that deposit several tens of kilojoules in the compressed core of an imploded DT shell. We review recent progress in the understanding of intense laser- plasma interactions (LPI) relevant to fast ignition. Increases in computational and modeling capabilities, as well as algorithmic developments have led to enhancement in our ability to perform multidimensional particle-in-cell (PIC) simulations of LPI at relevant scales. We discuss the physics of the interaction in terms of laser absorption fraction, the laser-generated electron spectra, divergence, and their temporal evolution. Scaling with irradiation conditions such as laser intensity, f-number and wavelength are considered, as well as the dependence on plasma parameters. Different numerical modeling approaches and configurations are addressed, providing an overview of the modeling capabilities and limitations. In addition, we discuss the comparison of simulation results with experimental observables. In particular, we address the question of surrogacy of today's experiments for the full-scale fast ignition problem.

  18. Laser–plasma interactions for fast ignition

    DOE PAGES

    Kemp, A. J.; Fiuza, F.; Debayle, A.; ...

    2014-04-17

    In the electron-driven fast-ignition approach to inertial confinement fusion, petawatt laser pulses are required to generate MeV electrons that deposit several tens of kilojoules in the compressed core of an imploded DT shell. We review recent progress in the understanding of intense laser- plasma interactions (LPI) relevant to fast ignition. Increases in computational and modeling capabilities, as well as algorithmic developments have led to enhancement in our ability to perform multidimensional particle-in-cell (PIC) simulations of LPI at relevant scales. We discuss the physics of the interaction in terms of laser absorption fraction, the laser-generated electron spectra, divergence, and their temporalmore » evolution. Scaling with irradiation conditions such as laser intensity, f-number and wavelength are considered, as well as the dependence on plasma parameters. Different numerical modeling approaches and configurations are addressed, providing an overview of the modeling capabilities and limitations. In addition, we discuss the comparison of simulation results with experimental observables. In particular, we address the question of surrogacy of today's experiments for the full-scale fast ignition problem.« less

  19. Fast temperature relaxation model in dense plasmas

    NASA Astrophysics Data System (ADS)

    Faussurier, Gérald; Blancard, Christophe

    2017-01-01

    We present a fast model to calculate the temperature-relaxation rates in dense plasmas. The electron-ion interaction-potential is calculated by combining a Yukawa approach and a finite-temperature Thomas-Fermi model. We include the internal energy as well as the excess energy of ions using the QEOS model. Comparisons with molecular dynamics simulations and calculations based on an average-atom model are presented. This approach allows the study of the temperature relaxation in a two-temperature electron-ion system in warm and hot dense matter.

  20. Misled by the Morning "Fasting" Plasma Glucose.

    PubMed

    King, Allen B

    2015-05-13

    Because of its ease and simplicity of its measurement, the morning fasting plasma glucose (FPG), has been as used a surrogate marker for the entire basal day when titrating once-nightly basal insulin. Common in obese insulin-treated patients with type 2 diabetes, late and large evening meals elevate the FPG. This has led to dosing of basal insulin well beyond the basal requirements and contributes to hypoglycemia and weight gain seen with this therapy. It is recommended that during basal insulin titration, the evening meal be limited and hypoglycemia be monitored early in the morning, that bewitching time when the "peakless" basal insulin's action is peaking and the predawn phenomenon insulin sensitivity is higher. © 2015 Diabetes Technology Society.

  1. Citrate in plasma and urine during total fasting.

    PubMed

    Nielsen, T T; Sørensen, N S

    1979-01-01

    Plasma citrate was determined in 12 obese subjects who underwent total fasting for 10 days. Mean plasma citrate concentration rose significantly from 128 before to 205 micro mol/1 on the 10th day of fasting. Plasma citrate rose continuously during fasting in seven subjects in whom daily determinations were carried out. The 24-hour urinary citrate excretion was followed in six subjects. A significant decrease was found from 2.91 mmol/24 h in the prefasting state to 0.25 mmol/24 h at the end of the fast. Intravenous glucose tolerance test were performed before and on the 10th day of fasting. Kivgtt decreased significantly and was inversely related to plasma citrate concentration on the 10th day of fasting. The results agree well with the concept that an increased citrate level of tissues is of regulatory importance for the decreased glucose utilization during fasting in man.

  2. Fast Camera Movies of NSTX Plasmas

    DOE Data Explorer

    Maqueda, Ricky; Wurden, Glenn

    The National Spherical Torus Experiment (NSTX) is an innovative magnetic fusion device that is being used to study the physics principles of spherically shaped plasmas -- hot ionized gases in which nuclear fusion will occur under the appropriate conditions of temperature, density, and confinement in a magnetic field. Fusion is the energy source of the Sun and all the stars. Scientists believe it can provide an inexhaustible, safe, and environmentally attractive source. NSTX was constructed by the Princeton Plasma Physics Laboratory (PPPL) in conjunction with Oak Ridge National Laboratory, Columbia University, and the University of Washington Seattle. The original TIF images recorded by the KODAK digital camera (i.e., "raw data") are available, using the contact information given on the same web page that provides access to these fast camera movies. MPEG clips are organized under the following headings: • Gas Puff Imaging (GPI) diagnostic • GPI experiments • H-modes (longer) • H-modes (short) • Coaxial Helicity Injection experiments More than 100 MPEGS dating back to 1999 are available for public access.

  3. Laser-plasma interactions for fast ignition

    NASA Astrophysics Data System (ADS)

    Kemp, A. J.; Fiuza, F.; Debayle, A.; Johzaki, T.; Mori, W. B.; Patel, P. K.; Sentoku, Y.; Silva, L. O.

    2014-05-01

    In the electron-driven fast-ignition (FI) approach to inertial confinement fusion, petawatt laser pulses are required to generate MeV electrons that deposit several tens of kilojoules in the compressed core of an imploded DT shell. We review recent progress in the understanding of intense laser-plasma interactions (LPI) relevant to FI. Increases in computational and modelling capabilities, as well as algorithmic developments have led to enhancement in our ability to perform multi-dimensional particle-in-cell simulations of LPI at relevant scales. We discuss the physics of the interaction in terms of laser absorption fraction, the laser-generated electron spectra, divergence, and their temporal evolution. Scaling with irradiation conditions such as laser intensity are considered, as well as the dependence on plasma parameters. Different numerical modelling approaches and configurations are addressed, providing an overview of the modelling capabilities and limitations. In addition, we discuss the comparison of simulation results with experimental observables. In particular, we address the question of surrogacy of today's experiments for the full-scale FI problem.

  4. Fast Plasma Investigation for Magnetospheric Multiscale

    NASA Technical Reports Server (NTRS)

    Pollock, C.; Moore, T.; Coffey, V.; Dorelli J.; Giles, B.; Adrian, M.; Chandler, M.; Duncan, C.; Figueroa-Vinas, A.; Garcia, K.; hide

    2016-01-01

    The Fast Plasma Investigation (FPI) was developed for flight on the Magnetospheric Multiscale (MMS) mission to measure the differential directional flux of magnetospheric electrons and ions with unprecedented time resolution to resolve kinetic-scale plasma dynamics. This increased resolution has been accomplished by placing four dual 180-degree top hat spectrometers for electrons and four dual 180-degree top hat spectrometers for ions around the periphery of each of four MMS spacecraft. Using electrostatic field-of-view deflection, the eight spectrometers for each species together provide 4pi-sr-field-of-view with, at worst, 11.25-degree sample spacing. Energy/charge sampling is provided by swept electrostatic energy/charge selection over the range from 10 eVq to 30000 eVq. The eight dual spectrometers on each spacecraft are controlled and interrogated by a single block redundant Instrument Data Processing Unit, which in turn interfaces to the observatory's Instrument Suite Central Instrument Data processor. This paper described the design of FPI, its ground and in-flight calibration, its operational concept, and its data products.

  5. Fast Plasma Investigation for Magnetospheric Multiscale

    NASA Astrophysics Data System (ADS)

    Pollock, C.; Moore, T.; Jacques, A.; Burch, J.; Gliese, U.; Saito, Y.; Omoto, T.; Avanov, L.; Barrie, A.; Coffey, V.; Dorelli, J.; Gershman, D.; Giles, B.; Rosnack, T.; Salo, C.; Yokota, S.; Adrian, M.; Aoustin, C.; Auletti, C.; Aung, S.; Bigio, V.; Cao, N.; Chandler, M.; Chornay, D.; Christian, K.; Clark, G.; Collinson, G.; Corris, T.; De Los Santos, A.; Devlin, R.; Diaz, T.; Dickerson, T.; Dickson, C.; Diekmann, A.; Diggs, F.; Duncan, C.; Figueroa-Vinas, A.; Firman, C.; Freeman, M.; Galassi, N.; Garcia, K.; Goodhart, G.; Guererro, D.; Hageman, J.; Hanley, J.; Hemminger, E.; Holland, M.; Hutchins, M.; James, T.; Jones, W.; Kreisler, S.; Kujawski, J.; Lavu, V.; Lobell, J.; LeCompte, E.; Lukemire, A.; MacDonald, E.; Mariano, A.; Mukai, T.; Narayanan, K.; Nguyan, Q.; Onizuka, M.; Paterson, W.; Persyn, S.; Piepgrass, B.; Cheney, F.; Rager, A.; Raghuram, T.; Ramil, A.; Reichenthal, L.; Rodriguez, H.; Rouzaud, J.; Rucker, A.; Saito, Y.; Samara, M.; Sauvaud, J.-A.; Schuster, D.; Shappirio, M.; Shelton, K.; Sher, D.; Smith, D.; Smith, K.; Smith, S.; Steinfeld, D.; Szymkiewicz, R.; Tanimoto, K.; Taylor, J.; Tucker, C.; Tull, K.; Uhl, A.; Vloet, J.; Walpole, P.; Weidner, S.; White, D.; Winkert, G.; Yeh, P.-S.; Zeuch, M.

    2016-03-01

    The Fast Plasma Investigation (FPI) was developed for flight on the Magnetospheric Multiscale (MMS) mission to measure the differential directional flux of magnetospheric electrons and ions with unprecedented time resolution to resolve kinetic-scale plasma dynamics. This increased resolution has been accomplished by placing four dual 180-degree top hat spectrometers for electrons and four dual 180-degree top hat spectrometers for ions around the periphery of each of four MMS spacecraft. Using electrostatic field-of-view deflection, the eight spectrometers for each species together provide 4pi-sr field-of-view with, at worst, 11.25-degree sample spacing. Energy/charge sampling is provided by swept electrostatic energy/charge selection over the range from 10 eV/q to 30000 eV/q. The eight dual spectrometers on each spacecraft are controlled and interrogated by a single block redundant Instrument Data Processing Unit, which in turn interfaces to the observatory's Instrument Suite Central Instrument Data Processor. This paper describes the design of FPI, its ground and in-flight calibration, its operational concept, and its data products.

  6. Fast Plasma Instrument for MMS: Simulation Results

    NASA Technical Reports Server (NTRS)

    Figueroa-Vinas, Adolfo; Adrian, Mark L.; Lobell, James V.; Simpson, David G.; Barrie, Alex; Winkert, George E.; Yeh, Pen-Shu; Moore, Thomas E.

    2008-01-01

    Magnetospheric Multiscale (MMS) mission will study small-scale reconnection structures and their rapid motions from closely spaced platforms using instruments capable of high angular, energy, and time resolution measurements. The Dual Electron Spectrometer (DES) of the Fast Plasma Instrument (FPI) for MMS meets these demanding requirements by acquiring the electron velocity distribution functions (VDFs) for the full sky with high-resolution angular measurements every 30 ms. This will provide unprecedented access to electron scale dynamics within the reconnection diffusion region. The DES consists of eight half-top-hat energy analyzers. Each analyzer has a 6 deg. x 11.25 deg. Full-sky coverage is achieved by electrostatically stepping the FOV of each of the eight sensors through four discrete deflection look directions. Data compression and burst memory management will provide approximately 30 minutes of high time resolution data during each orbit of the four MMS spacecraft. Each spacecraft will intelligently downlink the data sequences that contain the greatest amount of temporal structure. Here we present the results of a simulation of the DES analyzer measurements, data compression and decompression, as well as ground-based analysis using as a seed re-processed Cluster/PEACE electron measurements. The Cluster/PEACE electron measurements have been reprocessed through virtual DES analyzers with their proper geometrical, energy, and timing scale factors and re-mapped via interpolation to the DES angular and energy phase-space sampling measurements. The results of the simulated DES measurements are analyzed and the full moments of the simulated VDFs are compared with those obtained from the Cluster/PEACE spectrometer using a standard quadrature moment, a newly implemented spectral spherical harmonic method, and a singular value decomposition method. Our preliminary moment calculations show a remarkable agreement within the uncertainties of the measurements, with the

  7. Fast Plasma Instrument for MMS: Simulation Results

    NASA Technical Reports Server (NTRS)

    Figueroa-Vinas, Adolfo; Adrian, Mark L.; Lobell, James V.; Simpson, David G.; Barrie, Alex; Winkert, George E.; Yeh, Pen-Shu; Moore, Thomas E.

    2008-01-01

    Magnetospheric Multiscale (MMS) mission will study small-scale reconnection structures and their rapid motions from closely spaced platforms using instruments capable of high angular, energy, and time resolution measurements. The Dual Electron Spectrometer (DES) of the Fast Plasma Instrument (FPI) for MMS meets these demanding requirements by acquiring the electron velocity distribution functions (VDFs) for the full sky with high-resolution angular measurements every 30 ms. This will provide unprecedented access to electron scale dynamics within the reconnection diffusion region. The DES consists of eight half-top-hat energy analyzers. Each analyzer has a 6 deg. x 11.25 deg. Full-sky coverage is achieved by electrostatically stepping the FOV of each of the eight sensors through four discrete deflection look directions. Data compression and burst memory management will provide approximately 30 minutes of high time resolution data during each orbit of the four MMS spacecraft. Each spacecraft will intelligently downlink the data sequences that contain the greatest amount of temporal structure. Here we present the results of a simulation of the DES analyzer measurements, data compression and decompression, as well as ground-based analysis using as a seed re-processed Cluster/PEACE electron measurements. The Cluster/PEACE electron measurements have been reprocessed through virtual DES analyzers with their proper geometrical, energy, and timing scale factors and re-mapped via interpolation to the DES angular and energy phase-space sampling measurements. The results of the simulated DES measurements are analyzed and the full moments of the simulated VDFs are compared with those obtained from the Cluster/PEACE spectrometer using a standard quadrature moment, a newly implemented spectral spherical harmonic method, and a singular value decomposition method. Our preliminary moment calculations show a remarkable agreement within the uncertainties of the measurements, with the

  8. Safety shutdown separators

    DOEpatents

    Carlson, Steven Allen; Anakor, Ifenna Kingsley; Farrell, Greg Robert

    2015-06-30

    The present invention pertains to electrochemical cells which comprise (a) an anode; (b) a cathode; (c) a solid porous separator, such as a polyolefin, xerogel, or inorganic oxide separator; and (d) a nonaqueous electrolyte, wherein the separator comprises a porous membrane having a microporous coating comprising polymer particles which have not coalesced to form a continuous film. This microporous coating on the separator acts as a safety shutdown layer that rapidly increases the internal resistivity and shuts the cell down upon heating to an elevated temperature, such as 110.degree. C. Also provided are methods for increasing the safety of an electrochemical cell by utilizing such separators with a safety shutdown layer.

  9. Fast photography of plasma formed by laser ablation of aluminum

    NASA Astrophysics Data System (ADS)

    Nedanovska, E.; Ivkovic, M.

    2008-07-01

    In this paper we present results of the temporal and spatial analysis of laser induced plasma performed by use of ICCD fast photography. The plasma is formed by excimer laser ablation of aluminum target in vacuum, air or different pressures of argon and helium. It is shown how the plasma luminous intensity and duration depends on gas pressure. The obtained time dependence of wave propagation distance is also compared with predictions given by the blast wave and drag-force theory also.

  10. EVOLUTION OF FAST MAGNETOACOUSTIC PULSES IN RANDOMLY STRUCTURED CORONAL PLASMAS

    SciTech Connect

    Yuan, D.; Li, B.; Pascoe, D. J.; Nakariakov, V. M.; Keppens, R. E-mail: bbl@sdu.edu.cn

    2015-02-01

    We investigate the evolution of fast magnetoacoustic pulses in randomly structured plasmas, in the context of large-scale propagating waves in the solar atmosphere. We perform one-dimensional numerical simulations of fast wave pulses propagating perpendicular to a constant magnetic field in a low-β plasma with a random density profile across the field. Both linear and nonlinear regimes are considered. We study how the evolution of the pulse amplitude and width depends on their initial values and the parameters of the random structuring. Acting as a dispersive medium, a randomly structured plasma causes amplitude attenuation and width broadening of the fast wave pulses. After the passage of the main pulse, secondary propagating and standing fast waves appear. Width evolution of both linear and nonlinear pulses can be well approximated by linear functions; however, narrow pulses may have zero or negative broadening. This arises because narrow pulses are prone to splitting, while broad pulses usually deviate less from their initial Gaussian shape and form ripple structures on top of the main pulse. Linear pulses decay at an almost constant rate, while nonlinear pulses decay exponentially. A pulse interacts most efficiently with a random medium with a correlation length of about half of the initial pulse width. This detailed model of fast wave pulses propagating in highly structured media substantiates the interpretation of EIT waves as fast magnetoacoustic waves. Evolution of a fast pulse provides us with a novel method to diagnose the sub-resolution filamentation of the solar atmosphere.

  11. Fast Magnetic Reconnection: Bridging Laboratory and Space Plasma Physics

    SciTech Connect

    Bhattacharjee, Amitava

    2012-02-16

    Recent developments in experimental and theoretical studies of magnetic reconnection hold promise for providing solutions to outstanding problems in laboratory and space plasma physics. Examples include sawtooth crashes in tokamaks, substorms in the Earth’s Magnetosphere, eruptive solar flares, and more recently, fast reconnection in laser-produced high energy density plasmas. In each of these examples, a common and long-standing challenge has been to explain why fast reconnection proceeds rapidly from a relatively quiescent state. In this talk, we demonstrate the advantages of viewing these problems and their solutions from a common perspective. We focus on some recent, surprising discoveries regarding the role of secondary plasmoid instabilities of thin current sheets. Nonlinearly, these instabilities lead to fast reconnection rates that are very weakly dependent on the Lundquist number of the plasma.

  12. Interaction of fast magnetoacoustic solitons in dense plasmas

    SciTech Connect

    Jahangir, R.; Saleem, Khalid; Masood, W.; Siddiq, M.; Batool, Nazia

    2015-09-15

    One dimensional propagation of fast magnetoacoustic solitary waves in dense plasmas with degenerate electrons is investigated in this paper in the small amplitude limit. In this regard, Korteweg deVries equation is derived and discussed using the plasma parameters that are typically found in white dwarf stars. The interaction of fast magnetoacoustic solitons is explored by using the Hirota bilinear formalism, which admits multi soliton solutions. It is observed that the values of the propagation vectors determine the interaction of solitary waves. It is further noted that the amplitude of the respective solitary waves remain unchanged after the interaction; however, they do experience a phase shift.

  13. High power, fast, microwave components based on beam generated plasmas

    NASA Astrophysics Data System (ADS)

    Manheimer, W. M.; Fernsler, R. F.; Gitlin, M. S.

    1998-10-01

    It is shown that the agile mirror plasma, under development as a device to simply and cheaply give electronic steering to microwave beams, also has application as a fast, electronically controlled, high power reflector, or phase shifter. In a radar system, this can lead to such applications as pulse to pulse polarization agility and electronic control of antenna gain, as well as to innovative approaches to high power millimeter wave circulators. The basic theory of the enhanced glow plasma is also developed.

  14. New Apparatus to Study Fast Atomic Recombination in Ultracold Plasma

    NASA Astrophysics Data System (ADS)

    Lim, Michael; Willis, Lucas

    2006-10-01

    We have constructed an apparatus to study the early evolution (0-1000 ns) of ultracold plasma, produced by photo-ionization of rubidium atoms in a magneto-optical trap. We report on progress toward measuring recombined atomic populations in ultracold plasma using ramped field ionization. The new setup features fast deflector plates to avoid saturation of the multi-channel plate detector, as well as close atmospheric access to the ultra-high vacuum interaction region.

  15. Fast Tunable Microwave Devices Using Self-driven Plasma Instabilities

    NASA Astrophysics Data System (ADS)

    Biggs, David; Cappelli, Mark

    2016-10-01

    Tunable electromagnetic devices using plasmas are of interest for various applications such as high frequency communications and analog signal processing. At microwave frequencies of tens of gigahertz, low-pressure plasmas must be employed in order to avoid high wave damping from collisions. The drawback of low-pressure plasmas is that their diffusion timescales are long, on the order of hundreds of microseconds. Other mechanisms than diffusion must be employed to achieve fast tuning capabilities of these devices. One candidate mechanism is to use a self-driven plasma instability, which may allow for fast tuning of microwave resonant cavities. In this work, a microwave resonant cavity is studied consisting of a rectangular waveguide with two conducting posts spaced along the propagation direction to form a rectangular cavity. The cavity acts as a band pass filter and transmits microwave signals around its resonant frequency. Plasma may be introduced into the cavity between the conducting posts in order to change the refractive index and thus the resonant and transmission frequency of the device. The location of the plasma and its plasma density are important parameters in determining the resonant frequency, and both parameters are capable of being tuned with plasma instabilities. This work is supported by the Air Force Office of Scientific Research.

  16. Progress toward measuring fast atomic recombination in ultracold plasma

    NASA Astrophysics Data System (ADS)

    Lim, Michael; Willis, Lucas

    2007-06-01

    We report on progress toward measuring the time-dependent distribution of atomic energy levels populated by recombination and collisions in ultracold plasma. The plasma is produced by direct photo-ionization of rubidium atoms in a magneto-optical trap. Our primary goal is to measure the changing Rydberg atom distribution in the first microsecond after plasma creation. Although predictions have been made for system behavior in this interval, this type of measurement has been elusive. Our apparatus features fast deflector plates to prevent saturation of the multi-channel plate detector, which is one of the main technical obstacles in this effort.

  17. Physical conditions for fast reconnection evolution in space plasmas

    SciTech Connect

    Ugai, M.

    2012-07-15

    The present paper studies physical conditions for fast reconnection mechanism involving slow shocks to evolve spontaneously in space (high-temperature) plasmas. This is fundamental for onset mechanisms of geomagnetic substorms and solar flares. It is demonstrated that reconnection evolution strongly depends on effective resistivity available in space plasmas as well as on dimensions of initial current sheet. If a current sheet is sufficiently thin, fast reconnection spontaneously evolves only when resistivity is locally enhanced around X reconnection point. This is because in space plasmas reconnection flows cause vital current concentration locally around X point. For current-driven anomalous resistivity, the resulting resistivity is automatically localized around X point, so fast reconnection mechanism can be realized. On the other hand, for uniform or Spitzer resistivity, any fast reconnection cannot grow; in particular, Spitzer resistivity is reduced around X point because of Joule heating. Regarding reconnection simulations (either fluid or particle), unless numerical resistivities are made negligibly small, they seriously mask the effects of physical resistivity, leading to a misleading conclusion that reconnection evolution is little influenced by plasma resistivity.

  18. Measuring Fast Ion Losses in a Reversed Field Pinch Plasma

    NASA Astrophysics Data System (ADS)

    Bonofiglo, P. J.; Anderson, J. K.; Almagri, A. F.; Kim, J.; Clark, J.; Capecchi, W.; Sears, S. H.

    2015-11-01

    The reversed field pinch (RFP) provides a unique environment to study fast ion confinement and transport. The RFP's weak toroidal field, strong magnetic shear, and ability to enter a 3D state provide a wide range of dynamics to study fast ions. Core-localized, 25 keV fast ions are sourced into MST by a tangentially injected hydrogen/deuterium neutral beam. Neutral particle analysis and measured fusion neutron flux indicate enhanced fast ion transport in the plasma core. Past experiments point to a dynamic loss of fast ions associated with the RFP's transition to a 3D state and with beam-driven, bursting magnetic modes. Consequently, fast ion transport and losses in the RFP have garnered recent attention. Valuable information on fast-ion loss, such as energy and pitch distributions, are sought to provide a better understanding of the transport mechanisms at hand. We have constructed and implemented two fast ion loss detectors (FILDs) for use on MST. The FILDs have two, independent, design concepts: collecting particles as a function of v⊥ or with pitch greater than 0.8. In this work, we present our preliminary findings and results from our FILDs on MST. This research is supported by US DOE.

  19. Direct heating of imploded plasma in the fast ignition

    NASA Astrophysics Data System (ADS)

    Sunahara, Atsushi; Johzaki, Tomoyuki; Nagatomo, Hideo; Mima, Kunioki; Shiraga, Hiroyuki; Azechi, Hiroshi; Mori, Yohitaga; Kitagawa, Yoneyoshi

    2016-03-01

    We propose the direct heating of an imploded plasma core by ultra-intense lasers in inertial confinement fusion, to increase the heating coupling efficiency. In this scheme, both fast-electrons and fast-ions heat the plasma core. Experiments using this direct heating scheme has been carried out at GXII and LFEX laser facility at Osaka Univeristy. To model this direct heating scheme, we developed the 1D simulation model and carried out simulations using the experimental conditions. Comparison between results of the simulation and the experimental observations validates the simulation model. We show that even in the unoptimized experimental conditions used in simulations, our calculations show that the maximum temperature, 1.6 keV, of the CD plasma.

  20. Plasma instability in fast spherical discharge induced by a preionization

    NASA Astrophysics Data System (ADS)

    Antsiferov, P. S.; Dorokhin, L. A.

    2015-04-01

    As it was shown earlier, fast discharge (dI/dt ˜ 1012 A/s and Imax ≈ 40 kA) in a spherical cavity (Al2O3, inner diameter 11 mm, 4 mm apertures for the current supply) filled with working gas (Ar and Xe, pressure 80 Pa), results in the formation of a plasma with the form close to spherical. The physical mechanism can be the cumulation of a convergent shock wave, which was originated near the inner surface of the discharge cavity. It was also shown for the cylindrical fast discharge that the preionization influences the dynamics of the cylindrical convergent shock wave, its evolutions becomes faster. The present work is devoted to the study of the influence of the preionization on the plasma formation in the fast discharge with spherical geometry (Ar, 80 Pa). The inductive storage with plasma erosion opening switch was used as a current driver. The spatial structure of the discharge plasma was studied by means of a pin-hole camera with the microchannel plate (MCP) detector with time gate of 5 ns. The extreme ultra violet spectra were studied by means of the grazing incidence spectrometer with the same MCP detector with time gate of 20 ns. Beside the expected effects (reduction of the spherical plasma formation time and some increase of the electron temperature), the preionization of the discharge by the current 500 A results also in the development of the plasma instabilities and destruction of the compact plasma ball in several tens of nanoseconds. Possible mechanism of the instability is discussed.

  1. Plasma instability in fast spherical discharge induced by a preionization

    SciTech Connect

    Antsiferov, P. S.; Dorokhin, L. A.

    2015-04-07

    As it was shown earlier, fast discharge (dI/dt ∼ 10{sup 12 }A/s and I{sub max} ≈ 40 kA) in a spherical cavity (Al{sub 2}O{sub 3}, inner diameter 11 mm, 4 mm apertures for the current supply) filled with working gas (Ar and Xe, pressure 80 Pa), results in the formation of a plasma with the form close to spherical. The physical mechanism can be the cumulation of a convergent shock wave, which was originated near the inner surface of the discharge cavity. It was also shown for the cylindrical fast discharge that the preionization influences the dynamics of the cylindrical convergent shock wave, its evolutions becomes faster. The present work is devoted to the study of the influence of the preionization on the plasma formation in the fast discharge with spherical geometry (Ar, 80 Pa). The inductive storage with plasma erosion opening switch was used as a current driver. The spatial structure of the discharge plasma was studied by means of a pin-hole camera with the microchannel plate (MCP) detector with time gate of 5 ns. The extreme ultra violet spectra were studied by means of the grazing incidence spectrometer with the same MCP detector with time gate of 20 ns. Beside the expected effects (reduction of the spherical plasma formation time and some increase of the electron temperature), the preionization of the discharge by the current 500 A results also in the development of the plasma instabilities and destruction of the compact plasma ball in several tens of nanoseconds. Possible mechanism of the instability is discussed.

  2. Resonance absorption of propagating fast waves in a cold plasma

    NASA Technical Reports Server (NTRS)

    Hollweg, Joseph V.

    1990-01-01

    Absorption of propagating waves impinging on a surface in which the plasma and magnetic field may change is investigated by examining in depth the problem of a combination of cold plasma, uniform magnetic field and a surface density which varies linearly from zero at the left end to some finite value at the right end, beyond which the density is constant. Two cases are considered: one in which the plasma is a vacuum everywhere to the left of the surface (which may correspond to coronal conditions) and one in which the plasma density jumps to a very large value to the left of the surface (which may mimic the magnetosphere with the dense region at the left corresponding to the plasmasphere). A complete discussion of the resonance absorption of propagating fast waves for the case considered by Kiveloson and Southwood (1986) is presented, emphasizing approximate analytical results whenever possible; these results are then compared with exact numerical solutions.

  3. The Fast Plasma Investigation on the Magnetospheric Multiscale Mission

    NASA Astrophysics Data System (ADS)

    Rager, A. C.; Pollock, C. J.; Avanov, L. A.; Barrie, A. C.; Burch, J. L.; Chandler, M. O.; Clark, G. B.; Coffey, V. N.; Dickson, C.; Dorelli, J.; Ergun, R.; Fuselier, S. A.; Gliese, U.; Giles, B. L.; Holland, M. P.; Jacques, A. D.; Kreisler, S.; Lavraud, B.; MacDonald, E.; Mauk, B.; Moore, T. E.; Mukai, T.; Nakamura, R.; Rosnack, T.; Saito, Y.; Salo, C.; Sauvaud, J. A.; Smith, D. L.; Smith, S. E.; Torbert, R. B.; Yokota, S.

    2015-12-01

    Launched in March 2015, the Fast Plasma Investigation (FPI) instrument suite on the Magnetospheric Multiscale Mission (MMS) is producing the highest time and spatial resolution 3D electron and ion particle distribution function measurements to date. During FPI science operations, the four spacecraft maintain a tetrahedral formation such that 3D measurements of the plasma and field gradients are enabled. This allows the spacecraft to better investigate reconnection and to distinguish between spatial and temporal structures. In the first three months, we expect to observe magnetic phenomena such as dipolarization fronts, the plasma sheet boundary layer, magnetopause crossings, ion dispersive signatures of from remote reconnection sites, and magnetic holes. This poster is intended to supplement the invited talk on FPI results by Pollock et al. by providing further detail of the instrumentation and calibration, as well as a sampling of early magnetospheric plasma observations in the evening-side magnetotail, dusk flank, and afternoon magnetopause.

  4. Fusion-fission-fusion fast ignition plasma focus [rapid communication

    NASA Astrophysics Data System (ADS)

    Winterberg, F.

    2005-03-01

    A crucial advancement in the problem for the controlled release of energy by nuclear fusion appears possible by an autocatalytic fusion-fission-fusion microexplosion, where the deuterium-tritium (DT) fusion reaction of a dense magnetized DT plasma placed inside a thin liner made up of U238, Th232 (perhaps B10) releases a sufficient number of 14 MeV fusion neutrons which by fission reactions in the liner implode the liner on the DT plasma. The liner implosion increases the DT plasma density and with it the neutron output accelerating the fast fission reactions. Following the fast fission assisted ignition, a thermonuclear detonation wave can propagate into unburnt DT to reach a high gain. The simplest way for the realization of this concept appears to be the dense plasma focus configuration, amended with a nested high voltage magnetically insulated transmission line for the heating of the DT. The large magnetic field needed for the α-particle entrapment of the DT fusion reaction is here generated by the thermomagnetic Nernst effect, amplifying the magnetic field of the plasma focus current sheet.

  5. Nuclear reactor shutdown system

    DOEpatents

    Bhate, Suresh K.; Cooper, Martin H.; Riffe, Delmar R.; Kinney, Calvin L.

    1981-01-01

    An inherent shutdown system for a nuclear reactor having neutron absorbing rods affixed to an armature which is held in an upper position by a magnetic flux flowing through a Curie temperature material. The Curie temperature material is fixedly positioned about the exterior of an inner duct in an annular region through which reactor coolant flows. Elongated fuel rods extending from within the core upwardly toward the Curie temperature material are preferably disposed within the annular region. Upon abnormal conditions which result in high neutron flux and coolant temperature, the Curie material loses its magnetic permeability, breaking the magnetic flux path and allowing the armature and absorber rods to drop into the core, thus shutting down the fissioning reaction. The armature and absorber rods are retrieved by lowering the housing for the electromagnet forming coils which create a magnetic flux path which includes the inner duct wall. The coil housing then is raised, resetting the armature.

  6. Shutdown- All Hands

    NASA Image and Video Library

    2013-09-30

    Monday, September 30, 2013 - NASA Goddard civil servant and contractor employees were invited to an all hands meeting with Center Director Chris Scolese and members of the senior management team to learn the latest information about a possible partial government shutdown that could happen as early as midnight. Credit: NASA/Goddard/Bill Hrybyk NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  7. Focused beams of fast neutral atoms in glow discharge plasma

    NASA Astrophysics Data System (ADS)

    Grigoriev, S. N.; Melnik, Yu. A.; Metel, A. S.; Volosova, M. A.

    2017-06-01

    Glow discharge with electrostatic confinement of electrons in a vacuum chamber allows plasma processing of conductive products in a wide pressure range of p = 0.01 - 5 Pa. To assist processing of a small dielectric product with a concentrated on its surface beam of fast neutral atoms, which do not cause charge effects, ions from the discharge plasma are accelerated towards the product and transformed into fast atoms. The beam is produced using a negatively biased cylindrical or a spherical grid immersed in the plasma. Ions accelerated by the grid turn into fast neutral atoms at p > 0.1 Pa due to charge exchange collisions with gas atoms in the space charge sheaths adjoining the grid. The atoms form a diverging neutral beam and a converging beam propagating from the grid in opposite directions. The beam propagating from the concave surface of a 0.24-m-wide cylindrical grid is focused on a target within a 10-mm-wide stripe, and the beam from the 0.24-m-diameter spherical grid is focused within a 10-mm-diameter circle. At the bias voltage U = 5 kV and p ˜ 0.1 Pa, the energy of fast argon atoms is distributed continuously from zero to eU ˜ 5 keV. The pressure increase to 1 Pa results in the tenfold growth of their equivalent current and a decrease in the mean energy by an order of magnitude, which substantially raises the efficiency of material etching. Sharpening by the beam of ceramic knife-blades proved that the new method for the generation of concentrated fast atom beams can be effectively used for the processing of dielectric materials in vacuum.

  8. Interaction between high harmonic fast waves and fast ions in NSTX/NSTX-U plasmas

    NASA Astrophysics Data System (ADS)

    Bertelli, N.; Valeo, E. J.; Gorelenkova, M.; Green, D. L.; RF SciDAC Team

    2016-10-01

    Fast wave (FW) heating in the ion cyclotron range of frequency (ICRF) has been successfully used to sustain and control the fusion plasma performance, and it will likely play an important role in the ITER experiment. As demonstrated in the NSTX and DIII-D experiments the interactions between fast waves and fast ions can be so strong to significantly modify the fast ion population from neutral beam injection. In fact, it has been recently found in NSTX that FWs can modify and, under certain conditions, even suppress the energetic particle driven instabilities, such as toroidal Alfvén eigenmodes and global Alfvén eigenmodes and fishbones. This paper examines such interactions in NSTX/NSTX-U plasmas by using the recent extension of the RF full-wave code TORIC to include non-Maxwellian ions distribution functions. Particular attention is given to the evolution of the fast ions distribution function w/ and w/o RF. Tests on the RF kick-operator implemented in the Monte-Carlo particle code NUBEAM is also discussed in order to move towards a self consistent evaluation of the RF wave-field and the ion distribution functions in the TRANSP code. Work supported by US DOE Contract DE-AC02-09CH11466.

  9. Fast plasma heating by anomalous and inertial resistivity effects

    NASA Technical Reports Server (NTRS)

    Duijveman, A.; Hoyng, P.; Ionson, J. A.

    1981-01-01

    Fast plasma heating by anomalous and inertial resistivity effects is described. A small fraction of the plasma contains strong currents that run parallel to the magnetic field and are driven by an exponentiating electric field. The anomalous character of the current dissipation is caused by the excitation of electrostatic ion cyclotron and/or ion acoustic waves. The role of resistivity due to geometrical effects is considered. Through the use of a marginal stability analysis, equations for the average electron and ion temperatures are derived and numerically solved. The evolution of the plasma is described as a path in the drift velocity diagram, in which the drift velocity is plotted as a function of the electron to ion temperature ratio.

  10. Fast discharge in a plasma gun with hemispherical insulator

    NASA Astrophysics Data System (ADS)

    Antsiferov, P. S.; Dorokhin, L. A.; Sidelnikov, Yu. V.; Koshelev, K. N.

    2009-05-01

    A method of creation of hot dense plasma is proposed. It is based on cumulation of a shockwave, which originates on a hemispherical surface of insulator of plasma gun. The results of first experiments are presented. The shock wave is driven by fast electrical discharge (dI /dt>1012 A/s). The inductive storage with semiconductor opening switch is used as a current driver. Time resolved pin-hole images and vacuum ultraviolet (vuv) spectra are studied. Shockwaves from hemispherical insulator with 4 mm radius create plasma with a form of column about 1 mm diameter and 3-4 mm length. vuv spectra contain the lines of Ar ions that corresponds to the electron temperature about 20 eV. Possible practical application is discussed.

  11. Fast Fermi acceleration in the plasma sheet boundary layer

    NASA Technical Reports Server (NTRS)

    Wu, C. S.; Mandt, M. E.; Krauss-Varban, D.; Lui, A. T. Y.

    1989-01-01

    A longstanding question in the field of magnetospheric physics is the source of the energetic particles which are commonly observed along the plasma-sheet boundary layer (PSBL). Several models have been suggested for the acceleration of these particles. Here, a means is suggested by which the fast Fermi acceleration mechanism (Wu, 1984) can accelerate electrons at the plasma sheet and perhaps account for some of the observations. In this scheme, a localized hydromagnetic disturbance propagating through the tail lobe region impinges upon the PSBL, deforming it and displacing it in toward the central plasma sheet. The boundary layer can then act like a moving magnetic mirror. If the disturbance is propagating nearly perpendicular to the layer, then its velocity projected parallel to the layer (and the magnetic field) can be very large, resulting in significant acceleration of reflected particles.

  12. Fast discharge in a plasma gun with hemispherical insulator

    SciTech Connect

    Antsiferov, P. S.; Dorokhin, L. A.; Sidelnikov, Yu. V.; Koshelev, K. N.

    2009-05-15

    A method of creation of hot dense plasma is proposed. It is based on cumulation of a shockwave, which originates on a hemispherical surface of insulator of plasma gun. The results of first experiments are presented. The shock wave is driven by fast electrical discharge (dI/dt>10{sup 12} A/s). The inductive storage with semiconductor opening switch is used as a current driver. Time resolved pin-hole images and vacuum ultraviolet (vuv) spectra are studied. Shockwaves from hemispherical insulator with 4 mm radius create plasma with a form of column about 1 mm diameter and 3-4 mm length. vuv spectra contain the lines of Ar ions that corresponds to the electron temperature about 20 eV. Possible practical application is discussed.

  13. Fast Fermi acceleration in the plasma sheet boundary layer

    NASA Astrophysics Data System (ADS)

    Wu, C. S.; Mandt, M. E.; Krauss-Varban, D.; Lui, A. T. Y.

    1989-10-01

    A longstanding question in the field of magnetospheric physics is the source of the energetic particles which are commonly observed along the plasma-sheet boundary layer (PSBL). Several models have been suggested for the acceleration of these particles. Here, a means is suggested by which the fast Fermi acceleration mechanism (Wu, 1984) can accelerate electrons at the plasma sheet and perhaps account for some of the observations. In this scheme, a localized hydromagnetic disturbance propagating through the tail lobe region impinges upon the PSBL, deforming it and displacing it in toward the central plasma sheet. The boundary layer can then act like a moving magnetic mirror. If the disturbance is propagating nearly perpendicular to the layer, then its velocity projected parallel to the layer (and the magnetic field) can be very large, resulting in significant acceleration of reflected particles.

  14. Study of plasma heating induced by fast electrons

    SciTech Connect

    Morace, A.; Batani, D.; Redaelli, R.; Magunov, A.; Fourment, C.; Santos, J. J.; Malka, G.; Boscheron, A.; Nazarov, W.; Vinci, T.; Okano, Y.; Inubushi, Y.; Nishimura, H.; Flacco, A.; Spindloe, C.; Tolley, M.

    2009-12-15

    We studied the induced plasma heating in three different kinds of targets: mass limited, foam targets, and large mass targets. The experiment was performed at Alise Laser Facility of CEA/CESTA. The laser system emitted a approx1 ps pulse with approx10 J energy at a wavelength of approx1 {mu}m. Mass limited targets had three layers with thicknesses of 10 {mu}m C{sub 8}H{sub 8}, 1 {mu}m C{sub 8}H{sub 7}Cl, and 10 {mu}m C{sub 8}H{sub 8} with size of 100x100 {mu}m{sup 2}. Detailed spectroscopic analysis of x rays emitted from the Cl tracer showed that it was possible to heat up the plasma from mass limited targets to a temperature of approx250 eV with density of approx10{sup 21} cm{sup -3}. The plasma heating is only produced by fast electron transport in the target, being the 10 {mu}m C{sub 8}H{sub 8} overcoating thick enough to prevent any possible direct irradiation of the tracer layer even taking into account mass-ablation due to the prepulse. These results demonstrate that with mass limited targets, it is possible to generate a plasma heated up to several hundreds eV. It is also very important for research concerning high energy density phenomena and for fast ignition (in particular for the study of fast electrons transport and induced heating).

  15. Optimal shutdown management

    NASA Astrophysics Data System (ADS)

    Bottasso, C. L.; Croce, A.; Riboldi, C. E. D.

    2014-06-01

    The paper presents a novel approach for the synthesis of the open-loop pitch profile during emergency shutdowns. The problem is of interest in the design of wind turbines, as such maneuvers often generate design driving loads on some of the machine components. The pitch profile synthesis is formulated as a constrained optimal control problem, solved numerically using a direct single shooting approach. A cost function expressing a compromise between load reduction and rotor overspeed is minimized with respect to the unknown blade pitch profile. Constraints may include a load reduction not-to-exceed the next dominating loads, a not-to-be-exceeded maximum rotor speed, and a maximum achievable blade pitch rate. Cost function and constraints are computed over a possibly large number of operating conditions, defined so as to cover as well as possible the operating situations encountered in the lifetime of the machine. All such conditions are simulated by using a high-fidelity aeroservoelastic model of the wind turbine, ensuring the accuracy of the evaluation of all relevant parameters. The paper demonstrates the capabilities of the novel proposed formulation, by optimizing the pitch profile of a multi-MW wind turbine. Results show that the procedure can reliably identify optimal pitch profiles that reduce design-driving loads, in a fully automated way.

  16. Plasma Distribution in Mercury's Magnetosphere Derived from MESSENGER Magnetometer and Fast Imaging Plasma Spectrometer Observations

    NASA Technical Reports Server (NTRS)

    Korth, Haje; Anderson, Brian J.; Gershman, Daniel J.; Raines, Jim M.; Slavin, James A.; Zurbuchen, Thomas H.; Solomon, Sean C.; McNutt, Ralph L.

    2014-01-01

    We assess the statistical spatial distribution of plasma in Mercury's magnetosphere from observations of magnetic pressure deficits and plasma characteristics by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft. The statistical distributions of proton flux and pressure were derived from 10months of Fast Imaging Plasma Spectrometer (FIPS) observations obtained during the orbital phase of the MESSENGER mission. The Magnetometer-derived pressure distributions compare favorably with those deduced from the FIPS observations at locations where depressions in the magnetic field associated with the presence of enhanced plasma pressures are discernible in the Magnetometer data. The magnitudes of the magnetic pressure deficit and the plasma pressure agree on average, although the two measures of plasma pressure may deviate for individual events by as much as a factor of approximately 3. The FIPS distributions provide better statistics in regions where the plasma is more tenuous and reveal an enhanced plasma population near the magnetopause flanks resulting from direct entry of magnetosheath plasma into the low-latitude boundary layer of the magnetosphere. The plasma observations also exhibit a pronounced north-south asymmetry on the nightside, with markedly lower fluxes at low altitudes in the northern hemisphere than at higher altitudes in the south on the same field line. This asymmetry is consistent with particle loss to the southern hemisphere surface during bounce motion in Mercury's offset dipole magnetic field.

  17. Startup, Shutdown, & Malfunction (SSM) Emissions

    EPA Pesticide Factsheets

    EPA issued a final action to ensure states have plans in place that are fully consistent with the Clean Air Act and recent court decisions concerning startup, shutdown and malfunction (SSM) operations.

  18. Gestational diabetes mellitus: Screening with fasting plasma glucose

    PubMed Central

    Agarwal, Mukesh M

    2016-01-01

    Fasting plasma glucose (FPG) as a screening test for gestational diabetes mellitus (GDM) has had a checkered history. During the last three decades, a few initial anecdotal reports have given way to the recent well-conducted studies. This review: (1) traces the history; (2) weighs the advantages and disadvantages; (3) addresses the significance in early pregnancy; (4) underscores the benefits after delivery; and (5) emphasizes the cost savings of using the FPG in the screening of GDM. It also highlights the utility of fasting capillary glucose and stresses the value of the FPG in circumventing the cumbersome oral glucose tolerance test. An understanding of all the caveats is crucial to be able to use the FPG for investigating glucose intolerance in pregnancy. Thus, all health professionals can use the patient-friendly FPG to simplify the onerous algorithms available for the screening and diagnosis of GDM - thereby helping each and every pregnant woman. PMID:27525055

  19. Interplay between fast ions and turbulence in magnetic fusion plasmas

    NASA Astrophysics Data System (ADS)

    Dumont, R. J.; Zarzoso, D.; Sarazin, Y.; Garbet, X.; Strugarek, A.; Abiteboul, J.; Cartier-Michaud, T.; Dif-Pradalier, G.; Ghendrih, Ph; Girardo, J.-B.; Grandgirard, V.; Latu, G.; Passeron, C.; Thomine, O.

    2013-12-01

    Evidence for the impact of energetic particles (EPs) on turbulence is given in this paper. Firstly, the excitation of electrostatic instabilities in linear gyrokinetic simulations performed with the global GYSELA code by introducing distribution functions typical of fast ions in tokamak plasmas is presented. The obtained mode is unambiguously characterized as an EGAM, i.e. a geodesic acoustic mode (GAM) excited by EPs. The influence of EGAMs on turbulence and associated transport is then analyzed by implementing a source adapted to the inclusion of fast particle populations in non-linear simulations. This source successfully excites EGAMs in the presence of turbulence, which leads to a drastic reduction of the turbulent transport. However, this reduction is only transient; it is followed by an increase of the turbulent activity, characterized by a complex interaction between the EGAMs and the turbulence. In the subsequent steady-state regime, turbulent transport appears to be modulated at the EGAM frequency.

  20. Control rod drive for reactor shutdown

    DOEpatents

    McKeehan, Ernest R.; Shawver, Bruce M.; Schiro, Donald J.; Taft, William E.

    1976-01-20

    A means for rapidly shutting down or scramming a nuclear reactor, such as a liquid metal-cooled fast breeder reactor, and serves as a backup to the primary shutdown system. The control rod drive consists basically of an in-core assembly, a drive shaft and seal assembly, and a control drive mechanism. The control rod is driven into the core region of the reactor by gravity and hydraulic pressure forces supplied by the reactor coolant, thus assuring that common mode failures will not interfere with or prohibit scramming the reactor when necessary.

  1. Modulational instability of fast magnetosonic waves in a solar plasma

    NASA Astrophysics Data System (ADS)

    Sakai, J.-I.

    1983-04-01

    A set of coupled equations describing the modulational instability, including gravity, is derived from the MHD. It is noted that the results obtained here may figure prominently in processes of magnetic field line reconnection caused by nonlinear MHD waves (Sakai et al., 1982), as well as in explanations of the slow motions recently observed in the X-ray pictures during Skylab (Rust and Svestka, 1979). The modulational instability is discussed, and an estimate is made of the growth rate. Attention is also given to the applications of the modulational instability of fast modes to a solar plasma.

  2. Fast moving plasma structures in the distant magnetotail

    NASA Technical Reports Server (NTRS)

    Scholer, M.; Klecker, B.; Hovestadt, D.; Gloeckler, G.; Ipavich, F. M.; Smith, E. J.

    1984-01-01

    The paper reports for the first time the detailed time behavior of the intensities and the angular distributions of energetic protons and electrons in the distant magnetotail of the earth at 220 earth radii and 110 earth radii. The data have been obtained by the Max-Planck-Institut/University of Maryland sensor system on ISEE 3 during the spacecraft's first deep tail passage. Three energetic particle bursts are studied in detail. It is suggested that the satellite encounters detached plasma structures evidenced by the isotropic electrons. These structures, probably plasmoids, move with high velocities (about 800 km/s) down the tail. The energetic electrons and protons stream ahead of these fast tailward moving plasma structures, which leads to the various time dispersion effects. This allows, in principle, a determination of the source distance from the satellite.

  3. Observation of Ion Cyclotron Heating in a Fast-flowing Plasma for an Advanced Plasma Thruster

    NASA Astrophysics Data System (ADS)

    Ando, Akira; Hatanaka, Motoi; Shibata, Masaki; Tobari, Hiroyuki; Hattori, Kunihiko; Inutake, Masaaki

    2004-11-01

    In the Variable Specific Impulse Magnetoplasma Rocket (VASIMR) project in NASA, the combined system of the ion cyclotron heating and the magnetic nozzle is proposed to control a ratio of specific impulse to thrust at constant power. In order to establish the advanced plasma thruster, experiments of an ion heating and plasma acceleration by a magnetic nozzle are performed in a fast-flowing plasma in the HITOP device. A fast-flowing He plasma is produced by Magneto-Plasma-Dynamic Arcjet (MPDA) operated with an externally-applied magnetic field up to 1kG. RF waves with an ion cyclotron range of frequency (f=20-300kHz) is excited by a helically-wound antenna located downstream of the MPDA. Increases of an ion temperature and plasma stored energy measured by a diamagnetic coil clearly observed during the RF pulse. The heating efficiency is compared for various magnetic field configurations and strengths. There appears no indication of cyclotron resonance in a high density plasma where the ratio of ion cyclotron frequency to ion-ion collision one is below unity, because an ion-ion collisional effect is dominant. When the density becomes low and the ratio of ion cyclotron frequency to ion-ion collision one becomes high, features of ion cyclotron resonance are clearly appeared. The optimum magnetic field strength for the ion heating is slightly lower than that of the cyclotron resonance, which is caused by the Doppler effect due to the fast-flowing plasma. An ion energy distribution function is measured at a magnetic nozzle region by an electrostatic analyzer and increase of the parallel velocity is also observed.

  4. Hysteresis and fast timescales in transport relations of toroidal plasmas

    NASA Astrophysics Data System (ADS)

    Itoh, K.; Itoh, S.-I.; Ida, K.; Inagaki, S.; Kamada, Y.; Kamiya, K.; Dong, J. Q.; Hidalgo, C.; Evans, T.; Ko, W. H.; Park, H.; Tokuzawa, T.; Kubo, S.; Kobayashi, T.; Kosuga, Y.; Sasaki, M.; Yun, G. S.; Song, S. D.; Kasuya, N.; Nagashima, Y.; Moon, C.; Yoshinuma, M.; Makino, R.; Tsujimura, T.; Tsuchiya, H.; Stroth, U.

    2017-10-01

    This article assesses current understanding of hysteresis in transport relations, and its impact on the field. The rapid changes of fluxes compared to slow changes of plasma parameters are overviewed for both core and edge plasmas. The modulation ECH experiment is explained, in which the heating power cycles on-and-off periodically, revealing hysteresis and fast changes in the gradient-flux relation. The key finding is that hystereses were observed simultaneously in both the the gradient-flux and gradient-fluctuation relations. Hysteresis with rapid timescale exists in the channels of energy, electron and impurity densities, and plausibly in momentum. Advanced methods of data analysis are explained. Transport hysteresis can be studied by observing the higher harmonics of temperature perturbation δ Tm in heating modulation experiments. The hysteresis introduces the term δ Tm , which depends on the harmonic number m in an algebraic manner (not exponential decay). Next, the causes of hysteresis and its fast timescale are discussed. The nonlocal-in-space coupling works here, but does not suffice. One mechanism for ‘the heating heats turbulence’ is that the external source S in phase space for heating has its fluctuation in turbulent plasma. This coupling can induce the direct input of heating power into fluctuations. The height of the jump in transport hysteresis is smaller for heavier hydrogen isotopes, and could be one of the origins of isotope effects on confinement. Finally, the impacts of transport hysteresis on the control system are assessed. Control systems must be designed so as to protect the system from sudden plasma loss.

  5. Plasma distribution in Mercury's magnetosphere inferred from MESSENGER Magnetometer and Fast Imaging Plasma Spectrometer observations

    NASA Astrophysics Data System (ADS)

    Korth, H.; Anderson, B. J.; Raines, J. M.; Gershman, D. J.; Slavin, J. A.; Zurbuchen, T.; Solomon, S. C.; McNutt, R. L., Jr.

    2013-12-01

    We present average plasma distributions in Mercury's magnetosphere inferred independently from magnetic field and plasma measurements by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft. Plasma distributions were derived from magnetic pressure deficits measured during the first 10 months of MESSENGER orbital operations under the assumption of constant total pressure. Statistical distributions of proton flux and pressure were also derived from Fast Imaging Plasma Spectrometer (FIPS) observations during the same period. The pressures inferred from magnetic pressure deficits and the plasma data agree on average, although they differ by a factor of ~2 for individual events. The spatial distributions of magnetic pressure deficits derived from Magnetometer observations compare favorably with the distribution of proton pressure deduced from the FIPS observations. The FIPS distributions provide better statistics than the magnetic depression data in regions where the plasma is more tenuous and magnetic pressure deficits are difficult to identify definitively. The plasma data reveal features not previously identified in the Magnetometer data, such as an enhanced plasma population near the magnetopause flanks indicating entry of magnetosheath plasma into the low-latitude boundary layer of the magnetosphere. On nightside closed field lines, plasma pressures in the south are much greater than they are in the north. Locations of low plasma pressure in the north correspond to sample altitudes that map to southern conjugate locations below the planetary surface. The asymmetry is attributed to particle loss to the southern hemisphere surface during bounce motion in Mercury's magnetic field. The plasma observations confirm the northward offset in the planetary dipole.

  6. Collimated fast electron beam generation in critical density plasma

    SciTech Connect

    Iwawaki, T. Habara, H.; Morita, K.; Tanaka, K. A.; Baton, S.; Fuchs, J.; Chen, S.; Nakatsutsumi, M.; Rousseaux, C.; Filippi, F.; Nazarov, W.

    2014-11-15

    Significantly collimated fast electron beam with a divergence angle 10° (FWHM) is observed when an ultra-intense laser pulse (I = 10{sup 14 }W/cm{sup 2}, 300 fs) irradiates a uniform critical density plasma. The uniform plasma is created through the ionization of an ultra-low density (5 mg/c.c.) plastic foam by X-ray burst from the interaction of intense laser (I = 10{sup 14 }W/cm{sup 2}, 600 ps) with a thin Cu foil. 2D Particle-In-Cell (PIC) simulation well reproduces the collimated electron beam with a strong magnetic field in the region of the laser pulse propagation. To understand the physical mechanism of the collimation, we calculate energetic electron motion in the magnetic field obtained from the 2D PIC simulation. As the results, the strong magnetic field (300 MG) collimates electrons with energy over a few MeV. This collimation mechanism may attract attention in many applications such as electron acceleration, electron microscope and fast ignition of laser fusion.

  7. Fasting plasma glucose levels and coronary artery calcification in subjects with impaired fasting glucose.

    PubMed

    Eun, Young-Mi; Kang, Sung-Goo; Song, Sang-Wook

    2016-01-01

    Prediabetes is associated with an increased risk of cardiovascular disease (CVD). While the association of impaired glucose tolerance with CVD has been shown in many studies, the relationship between impaired fasting glucose (IFG) and CVD remains unclear. The purpose of this study was to compare the coronary artery calcium (CAC) scores of participants with normal fasting glucose versus those with IFG, according to fasting plasma glucose (FPG) levels, and to assess whether differences in CAC scores were independent of important confounders. Retrospective study. Health Promotion Center of the University Hospital (Gyeonggi-do, South Korea), during the period 2010-2014. Participants were enrolled from the general population who visited for a medical check-up. CAC was assessed in asymptomatic individuals by multidetector computed tomography. Anthropometric parameters and metabolic profiles were also recorded. Subjects were divided into four fasting glucose groups. Participants with a history of CVD or diabetes mellitus were excluded. Correlation between FPG and CAC scores, CAC score categories, and association between CAC score and FPG categories. Of 1112 participants, 346 (34.2%) had a CAC score > 0. FPG values in the IFG patients were positively but weakly correlated with CAC scores (r=0.099, P=.001). The incidence of CAC differed according to FPG level (P < .001) and in Kruskal-Wallis test the mean CAC score differed by FPG group (P < .001). After adjustment for other factors in a multiple logistic regression analysis, those subjects with FPG >=110 mg/dL had a significantly higher risk of CAC than did subjects with normal fasting glucose (110.

  8. Simulation of laser-plasma interactions and fast-electron transport in inhomogeneous plasma

    SciTech Connect

    Cohen, B.I. Kemp, A.J.; Divol, L.

    2010-06-20

    A new framework is introduced for kinetic simulation of laser-plasma interactions in an inhomogeneous plasma motivated by the goal of performing integrated kinetic simulations of fast-ignition laser fusion. The algorithm addresses the propagation and absorption of an intense electromagnetic wave in an ionized plasma leading to the generation and transport of an energetic electron component. The energetic electrons propagate farther into the plasma to much higher densities where Coulomb collisions become important. The high-density plasma supports an energetic electron current, return currents, self-consistent electric fields associated with maintaining quasi-neutrality, and self-consistent magnetic fields due to the currents. Collisions of the electrons and ions are calculated accurately to track the energetic electrons and model their interactions with the background plasma. Up to a density well above critical density, where the laser electromagnetic field is evanescent, Maxwell's equations are solved with a conventional particle-based, finite-difference scheme. In the higher-density plasma, Maxwell's equations are solved using an Ohm's law neglecting the inertia of the background electrons with the option of omitting the displacement current in Ampere's law. Particle equations of motion with binary collisions are solved for all electrons and ions throughout the system using weighted particles to resolve the density gradient efficiently. The algorithm is analyzed and demonstrated in simulation examples. The simulation scheme introduced here achieves significantly improved efficiencies.

  9. Hybrid Simulation of Laser-Plasma Interactions and Fast Electron Transport in Inhomogeneous Plasma

    SciTech Connect

    Cohen, B I; Kemp, A; Divol, L

    2009-05-27

    A new framework is introduced for kinetic simulation of laser-plasma interactions in an inhomogenous plasma motivated by the goal of performing integrated kinetic simulations of fast-ignition laser fusion. The algorithm addresses the propagation and absorption of an intense electromagnetic wave in an ionized plasma leading to the generation and transport of an energetic electron component. The energetic electrons propagate farther into the plasma to much higher densities where Coulomb collisions become important. The high-density plasma supports an energetic electron current, return currents, self-consistent electric fields associated with maintaining quasi-neutrality, and self-consistent magnetic fields due to the currents. Collisions of the electrons and ions are calculated accurately to track the energetic electrons and model their interactions with the background plasma. Up to a density well above critical density, where the laser electromagnetic field is evanescent, Maxwell's equations are solved with a conventional particle-based, finite-difference scheme. In the higher-density plasma, Maxwell's equations are solved using an Ohm's law neglecting the inertia of the background electrons with the option of omitting the displacement current in Ampere's law. Particle equations of motion with binary collisions are solved for all electrons and ions throughout the system using weighted particles to resolve the density gradient efficiently. The algorithm is analyzed and demonstrated in simulation examples. The simulation scheme introduced here achieves significantly improved efficiencies.

  10. The Electron and ion Plasma Experiment for Fast

    NASA Astrophysics Data System (ADS)

    Carlson, C. W.; McFadden, J. P.; Turin, P.; Curtis, D. W.; Magoncelli, A.

    2001-08-01

    The ion and electron plasma experiment on the Fast Auroral Snapshot satellite (FAST) is designed to measure pitch-angle distributions of suprathermal auroral electrons and ions with high sensitivity, wide dynamic range, good energy and angular resolution, and exceptional time resolution. These measurements support the primary scientific goal of the FAST mission to understand the physical processes responsible for auroral particle acceleration and heating, and associated wave-particle interactions. The instrument includes a complement of 8 pairs of `Top Hat' electrostatic analyzer heads with microchannel plate (MCP) electron multipliers and discrete anodes to provide angle resolved measurements. The analyzers are packaged in four instrument stacks, each containing four analyzers. These four stacks are equally spaced around the spacecraft spin plane. Analyzers mounted on opposite sides of the spacecraft operate in pairs such that their individual 180° fields of view combine to give an unobstructed 360° field of view in the spin plane. The earth's magnetic field is within a few degrees of the spin plane during most auroral crossings, so the time resolution for pitch-angle distribution measurements is independent of the spacecraft spin period. Two analyzer pairs serve as electron and ion spectrometers that obtain distributions of 48 energies at 32 angles every 78 ms. Their standard energy ranges are 4 eV to 32 keV for electrons and 3 eV to 24 keV for ions. These sensors also have deflection plates that can track the magnetic field direction within 10° of the spin plane to resolve narrow, magnetic field-aligned beams of electrons and ions. The remaining six analyzer pairs collectively function as an electron spectrograph, resolving distributions with 16 contiguous pitch-angle bins and a selectable trade-off of energy and time resolution. Two examples of possible operating modes are a maximum time resolution mode with 16 angles and 6 energies every 1.63 ms, or a

  11. A distinct metabolic signature predicts development of fasting plasma glucose

    PubMed Central

    2012-01-01

    Background High blood glucose and diabetes are amongst the conditions causing the greatest losses in years of healthy life worldwide. Therefore, numerous studies aim to identify reliable risk markers for development of impaired glucose metabolism and type 2 diabetes. However, the molecular basis of impaired glucose metabolism is so far insufficiently understood. The development of so called 'omics' approaches in the recent years promises to identify molecular markers and to further understand the molecular basis of impaired glucose metabolism and type 2 diabetes. Although univariate statistical approaches are often applied, we demonstrate here that the application of multivariate statistical approaches is highly recommended to fully capture the complexity of data gained using high-throughput methods. Methods We took blood plasma samples from 172 subjects who participated in the prospective Metabolic Syndrome Berlin Potsdam follow-up study (MESY-BEPO Follow-up). We analysed these samples using Gas Chromatography coupled with Mass Spectrometry (GC-MS), and measured 286 metabolites. Furthermore, fasting glucose levels were measured using standard methods at baseline, and after an average of six years. We did correlation analysis and built linear regression models as well as Random Forest regression models to identify metabolites that predict the development of fasting glucose in our cohort. Results We found a metabolic pattern consisting of nine metabolites that predicted fasting glucose development with an accuracy of 0.47 in tenfold cross-validation using Random Forest regression. We also showed that adding established risk markers did not improve the model accuracy. However, external validation is eventually desirable. Although not all metabolites belonging to the final pattern are identified yet, the pattern directs attention to amino acid metabolism, energy metabolism and redox homeostasis. Conclusions We demonstrate that metabolites identified using a high

  12. A distinct metabolic signature predicts development of fasting plasma glucose.

    PubMed

    Hische, Manuela; Larhlimi, Abdelhalim; Schwarz, Franziska; Fischer-Rosinský, Antje; Bobbert, Thomas; Assmann, Anke; Catchpole, Gareth S; Pfeiffer, Andreas Fh; Willmitzer, Lothar; Selbig, Joachim; Spranger, Joachim

    2012-02-02

    High blood glucose and diabetes are amongst the conditions causing the greatest losses in years of healthy life worldwide. Therefore, numerous studies aim to identify reliable risk markers for development of impaired glucose metabolism and type 2 diabetes. However, the molecular basis of impaired glucose metabolism is so far insufficiently understood. The development of so called 'omics' approaches in the recent years promises to identify molecular markers and to further understand the molecular basis of impaired glucose metabolism and type 2 diabetes. Although univariate statistical approaches are often applied, we demonstrate here that the application of multivariate statistical approaches is highly recommended to fully capture the complexity of data gained using high-throughput methods. We took blood plasma samples from 172 subjects who participated in the prospective Metabolic Syndrome Berlin Potsdam follow-up study (MESY-BEPO Follow-up). We analysed these samples using Gas Chromatography coupled with Mass Spectrometry (GC-MS), and measured 286 metabolites. Furthermore, fasting glucose levels were measured using standard methods at baseline, and after an average of six years. We did correlation analysis and built linear regression models as well as Random Forest regression models to identify metabolites that predict the development of fasting glucose in our cohort. We found a metabolic pattern consisting of nine metabolites that predicted fasting glucose development with an accuracy of 0.47 in tenfold cross-validation using Random Forest regression. We also showed that adding established risk markers did not improve the model accuracy. However, external validation is eventually desirable. Although not all metabolites belonging to the final pattern are identified yet, the pattern directs attention to amino acid metabolism, energy metabolism and redox homeostasis. We demonstrate that metabolites identified using a high-throughput method (GC-MS) perform well in

  13. Optimizing Dense Plasma Focus Neutron Yields with Fast Gas Jets

    NASA Astrophysics Data System (ADS)

    McMahon, Matthew; Kueny, Christopher; Stein, Elizabeth; Link, Anthony; Schmidt, Andrea

    2016-10-01

    We report a study using the particle-in-cell code LSP to perform fully kinetic simulations modeling dense plasma focus (DPF) devices with high density gas jets on axis. The high density jet models fast gas puffs which allow for more mass on axis while maintaining the optimal pressure for the DPF. As the density of the jet compared to the background fill increases we find the neutron yield increases, as does the variability in the neutron yield. Introducing perturbations in the jet density allow for consistent seeding of the m =0 instability leading to more consistent ion acceleration and higher neutron yields with less variability. Jets with higher on axis density are found to have the greatest yield. The optimal jet configuration is explored. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  14. Confirmation of shutdown cooling effects

    NASA Astrophysics Data System (ADS)

    Sato, Kotaro; Tabuchi, Masato; Sugimura, Naoki; Tatsumi, Masahiro

    2015-12-01

    After the Fukushima accidents, all nuclear power plants in Japan have gradually stopped their operations and have long periods of shutdown. During those periods, reactivity of fuels continues to change significantly especially for high-burnup UO2 fuels and MOX fuels due to radioactive decays. It is necessary to consider these isotopic changes precisely, to predict neutronics characteristics accurately. In this paper, shutdown cooling (SDC) effects of UO2 and MOX fuels that have unusual operation histories are confirmed by the advanced lattice code, AEGIS. The calculation results show that the effects need to be considered even after nuclear power plants come back to normal operation.

  15. Confirmation of shutdown cooling effects

    SciTech Connect

    Sato, Kotaro Tabuchi, Masato; Sugimura, Naoki; Tatsumi, Masahiro

    2015-12-31

    After the Fukushima accidents, all nuclear power plants in Japan have gradually stopped their operations and have long periods of shutdown. During those periods, reactivity of fuels continues to change significantly especially for high-burnup UO{sub 2} fuels and MOX fuels due to radioactive decays. It is necessary to consider these isotopic changes precisely, to predict neutronics characteristics accurately. In this paper, shutdown cooling (SDC) effects of UO{sub 2} and MOX fuels that have unusual operation histories are confirmed by the advanced lattice code, AEGIS. The calculation results show that the effects need to be considered even after nuclear power plants come back to normal operation.

  16. Dense magnetized plasma associated with a fast radio burst

    NASA Astrophysics Data System (ADS)

    Masui, Kiyoshi; Lin, Hsiu-Hsien; Sievers, Jonathan; Anderson, Christopher J.; Chang, Tzu-Ching; Chen, Xuelei; Ganguly, Apratim; Jarvis, Miranda; Kuo, Cheng-Yu; Li, Yi-Chao; Liao, Yu-Wei; McLaughlin, Maura; Pen, Ue-Li; Peterson, Jeffrey B.; Roman, Alexander; Timbie, Peter T.; Voytek, Tabitha; Yadav, Jaswant K.

    2015-12-01

    Fast radio bursts are bright, unresolved, non-repeating, broadband, millisecond flashes, found primarily at high Galactic latitudes, with dispersion measures much larger than expected for a Galactic source. The inferred all-sky burst rate is comparable to the core-collapse supernova rate out to redshift 0.5. If the observed dispersion measures are assumed to be dominated by the intergalactic medium, the sources are at cosmological distances with redshifts of 0.2 to 1 (refs 10 and 11). These parameters are consistent with a wide range of source models. One fast burst revealed circular polarization of the radio emission, but no linear polarization was detected, and hence no Faraday rotation measure could be determined. Here we report the examination of archival data revealing Faraday rotation in the fast radio burst FRB 110523. Its radio flux and dispersion measure are consistent with values from previously reported bursts and, accounting for a Galactic contribution to the dispersion and using a model of intergalactic electron density, we place the source at a maximum redshift of 0.5. The burst has a much higher rotation measure than expected for this line of sight through the Milky Way and the intergalactic medium, indicating magnetization in the vicinity of the source itself or within a host galaxy. The pulse was scattered by two distinct plasma screens during propagation, which requires either a dense nebula associated with the source or a location within the central region of its host galaxy. The detection in this instance of magnetization and scattering that are both local to the source favours models involving young stellar populations such as magnetars over models involving the mergers of older neutron stars, which are more likely to be located in low-density regions of the host galaxy.

  17. Dense magnetized plasma associated with a fast radio burst.

    PubMed

    Masui, Kiyoshi; Lin, Hsiu-Hsien; Sievers, Jonathan; Anderson, Christopher J; Chang, Tzu-Ching; Chen, Xuelei; Ganguly, Apratim; Jarvis, Miranda; Kuo, Cheng-Yu; Li, Yi-Chao; Liao, Yu-Wei; McLaughlin, Maura; Pen, Ue-Li; Peterson, Jeffrey B; Roman, Alexander; Timbie, Peter T; Voytek, Tabitha; Yadav, Jaswant K

    2015-12-24

    Fast radio bursts are bright, unresolved, non-repeating, broadband, millisecond flashes, found primarily at high Galactic latitudes, with dispersion measures much larger than expected for a Galactic source. The inferred all-sky burst rate is comparable to the core-collapse supernova rate out to redshift 0.5. If the observed dispersion measures are assumed to be dominated by the intergalactic medium, the sources are at cosmological distances with redshifts of 0.2 to 1 (refs 10 and 11). These parameters are consistent with a wide range of source models. One fast burst revealed circular polarization of the radio emission, but no linear polarization was detected, and hence no Faraday rotation measure could be determined. Here we report the examination of archival data revealing Faraday rotation in the fast radio burst FRB 110523. Its radio flux and dispersion measure are consistent with values from previously reported bursts and, accounting for a Galactic contribution to the dispersion and using a model of intergalactic electron density, we place the source at a maximum redshift of 0.5. The burst has a much higher rotation measure than expected for this line of sight through the Milky Way and the intergalactic medium, indicating magnetization in the vicinity of the source itself or within a host galaxy. The pulse was scattered by two distinct plasma screens during propagation, which requires either a dense nebula associated with the source or a location within the central region of its host galaxy. The detection in this instance of magnetization and scattering that are both local to the source favours models involving young stellar populations such as magnetars over models involving the mergers of older neutron stars, which are more likely to be located in low-density regions of the host galaxy.

  18. Fast reconnection in relativistic plasmas: the magnetohydrodynamics tearing instability revisited

    NASA Astrophysics Data System (ADS)

    Del Zanna, L.; Papini, E.; Landi, S.; Bugli, M.; Bucciantini, N.

    2016-08-01

    Fast reconnection operating in magnetically dominated plasmas is often invoked in models for magnetar giant flares, for magnetic dissipation in pulsar winds, or to explain the gamma-ray flares observed in the Crab nebula; hence, its investigation is of paramount importance in high-energy astrophysics. Here we study, by means of two-dimensional numerical simulations, the linear phase and the subsequent non-linear evolution of the tearing instability within the framework of relativistic resistive magnetohydrodynamics (MHD), as appropriate in situations where the Alfvén velocity approaches the speed of light. It is found that the linear phase of the instability closely matches the analysis in classical MHD, where the growth rate scales with the Lundquist number S as S-1/2, with the only exception of an enhanced inertial term due to the thermal and magnetic energy contributions. In addition, when thin current sheets of inverse aspect ratio scaling as S-1/3 are considered, the so-called ideal tearing regime is retrieved, with modes growing independently of S and extremely fast, on only a few light crossing times of the sheet length. The overall growth of fluctuations is seen to solely depend on the value of the background Alfvén velocity. In the fully non-linear stage, we observe an inverse cascade towards the fundamental mode, with Petschek-type supersonic jets propagating at the external Alfvén speed from the X-point, and a fast reconnection rate at the predicted value {R}˜ (ln S)^{-1}.

  19. Fast electron heating of dense plasma relevant to shock ignition

    NASA Astrophysics Data System (ADS)

    Fox, T. E.; Robinson, A. P. L.; Pasley, J.

    2013-10-01

    With an intensity in the range of 1016 W/cm2, the ignitor pulse in shock-ignition inertial confinement fusion is well above the threshold of parametric instabilities. Simulations (e.g. Klimo et al. 2011 Phys. Plasmas 18, 082709) indicate that a significant amount of energy will be deposited in energetic electrons with energies <100 keV and it has been proposed that these may play a beneficial role in enhancing the ignitor shock. Simulations by Gus'kov et al. (Phys. Rev. Lett. 109, 255004 (2012)) show that, under shock-ignition relevant conditions, a mono-energetic electron beam can drive strong shocks in a uniform plasma. We extend this study to the more realistic case of a Maxwellian energy distribution in the fast electron population. Having a distribution of electron mean-free-paths results in a more extended heating profile compared to a mono-energetic beam. However, we show it is still possible to launch strong shocks in this more realistic scenario and achieve equivalent pressures. The peak pressures achieved compare well with analytic scalings. We thank AWE for their financial assistance in support of the doctoral research of T. E. F.

  20. Intense Laser Plasma Interactions on the Road to Fast Ignition

    NASA Astrophysics Data System (ADS)

    van Woerkom, Linn

    2007-11-01

    Successful Fast Ignition (FI) offers the prospect of reduced laser driver energy and greater energy gain, which enhances the possibilities for realistic Inertial Confinement Fusion (ICF) energy power plants. The interaction of high intensity laser pulses with hot dense plasma lies at the core of the FI concept. At the most basic level FI relies on converting high energy, high intensity laser light into a beam of electrons which must propagate for 10's to ˜100 microns and deposit their energy in the compressed fuel. Thus, the process may be divided into two critical processes: 1) the generation of energetic electrons from the laser-matter interaction, and 2) the transport of energetic electrons through hot dense plasma. Experiments to date have only explored part of the FI relevant parameter space concerning laser energy, intensity, pulse duration, and transport of MeV particles. With the approach of first light on OMEGA EP and then NIF ARC, the field is poised to make crucial measurements that will determine the requirements for full scale FI. This talk will present recent results from high intensity laser-cone interactions that help pave the way to the next generation of experiments.

  1. EMERGENCY SHUTDOWN FOR NUCLEAR REACTORS

    DOEpatents

    Paget, J.A.; Koutz, S.L.; Stone, R.S.; Stewart, H.B.

    1963-12-24

    An emergency shutdown or scram apparatus for use in a nuclear reactor that includes a neutron absorber suspended from a temperature responsive substance that is selected to fail at a preselected temperature in excess of the normal reactor operating temperature, whereby the neutron absorber is released and allowed to fall under gravity to a preselected position within the reactor core is presented. (AEC)

  2. Effects of sex, age, and fasting conditions on plasma lipidomic profiles of fasted Sprague-Dawley rats.

    PubMed

    Saito, Kosuke; Ishikawa, Masaki; Murayama, Mayumi; Urata, Masayo; Senoo, Yuya; Toyoshima, Katsuko; Kumagai, Yuji; Maekawa, Keiko; Saito, Yoshiro

    2014-01-01

    Circulating lipid molecules reflect biological processes in the body and, thus, are useful tools for preclinical estimation of the efficacy and safety of newly developed drugs. However, background information on profiles of circulating lipid molecules in preclinical animal models is limited. Therefore, we examined the effects of multiple factors such as sex (fasted male vs. female), age (fasted 10 vs. 30 weeks old), and feeding conditions (feeding vs. fasting, 16 vs. 22 hr fasting, 10 AM vs. 4 PM blood collection), on the global profiles of lipid molecules in plasma from Sprague-Dawley rats by using a lipidomic approach. Our assay platform determined 262 lipid molecules (68 phospholipids, 20 sphingolipids, 138 neutral lipids, and 36 polyunsaturated fatty acids and their metabolites) in rat plasma. Multivariate discriminant analysis (orthogonal partial least squares discriminant analysis) and heat maps of statistically significant lipid molecules revealed that the plasma lipid profiles in rats are predominantly influenced by feeding conditions, followed by sex and age. In addition, the fasting duration (16 vs. 22 hr fasting) or the time of blood collection (10 AM vs. 4 PM blood collection) has limited or no contribution on the profiles of lipid molecules in rat plasma. Our results provide useful, fundamental information for exploring and validating biomarkers in future preclinical studies and may help to establish regulatory standards for such studies.

  3. Effects of Sex, Age, and Fasting Conditions on Plasma Lipidomic Profiles of Fasted Sprague-Dawley Rats

    PubMed Central

    Saito, Kosuke; Ishikawa, Masaki; Murayama, Mayumi; Urata, Masayo; Senoo, Yuya; Toyoshima, Katsuko; Kumagai, Yuji; Maekawa, Keiko; Saito, Yoshiro

    2014-01-01

    Circulating lipid molecules reflect biological processes in the body and, thus, are useful tools for preclinical estimation of the efficacy and safety of newly developed drugs. However, background information on profiles of circulating lipid molecules in preclinical animal models is limited. Therefore, we examined the effects of multiple factors such as sex (fasted male vs. female), age (fasted 10 vs. 30 weeks old), and feeding conditions (feeding vs. fasting, 16 vs. 22 hr fasting, 10 AM vs. 4 PM blood collection), on the global profiles of lipid molecules in plasma from Sprague-Dawley rats by using a lipidomic approach. Our assay platform determined 262 lipid molecules (68 phospholipids, 20 sphingolipids, 138 neutral lipids, and 36 polyunsaturated fatty acids and their metabolites) in rat plasma. Multivariate discriminant analysis (orthogonal partial least squares discriminant analysis) and heat maps of statistically significant lipid molecules revealed that the plasma lipid profiles in rats are predominantly influenced by feeding conditions, followed by sex and age. In addition, the fasting duration (16 vs. 22 hr fasting) or the time of blood collection (10 AM vs. 4 PM blood collection) has limited or no contribution on the profiles of lipid molecules in rat plasma. Our results provide useful, fundamental information for exploring and validating biomarkers in future preclinical studies and may help to establish regulatory standards for such studies. PMID:25375860

  4. Fast molecular tracking maps nanoscale dynamics of plasma membrane lipids

    PubMed Central

    Sahl, Steffen J.; Leutenegger, Marcel; Hilbert, Michael; Hell, Stefan W.; Eggeling, Christian

    2010-01-01

    We describe an optical method capable of tracking a single fluorescent molecule with a flexible choice of high spatial accuracy (∼10–20 nm standard deviation or ∼20–40 nm full-width-at-half-maximum) and temporal resolution (< 1 ms). The fluorescence signal during individual passages of fluorescent molecules through a spot of excitation light allows the sequential localization and thus spatio-temporal tracking of the molecule if its fluorescence is collected on at least three separate point detectors arranged in close proximity. We show two-dimensional trajectories of individual, small organic dye labeled lipids diffusing in the plasma membrane of living cells and directly observe transient events of trapping on < 20 nm spatial scales. The trapping is cholesterol-assisted and much more pronounced for a sphingo- than for a phosphoglycero-lipid, with average trapping times of ∼15 ms and < 4 ms, respectively. The results support previous STED nanoscopy measurements and suggest that, at least for nontreated cells, the transient interaction of a single lipid is confined to macromolecular dimensions. Our experimental approach demonstrates that fast molecular movements can be tracked with minimal invasion, which can reveal new important details of cellular nano-organization. PMID:20351247

  5. Fast Plasma Instrument for MMS: Data Compression Simulation Results

    NASA Astrophysics Data System (ADS)

    Barrie, A.; Adrian, M. L.; Yeh, P.; Winkert, G.; Lobell, J.; Vinas, A. F.; Simpson, D. G.

    2009-12-01

    Magnetospheric Multiscale (MMS) mission will study small-scale reconnection structures and their rapid motions from closely spaced platforms using instruments capable of high angular, energy, and time resolution measurements. To meet these requirements, the Fast Plasma Instrument (FPI) consists of eight (8) identical half top-hat electron sensors and eight (8) identical ion sensors and an Instrument Data Processing Unit (IDPU). The sensors (electron or ion) are grouped into pairs whose 6° x 180° fields-of-view (FOV) are set 90° apart. Each sensor is equipped with electrostatic aperture steering to allow the sensor to scan a 45° x 180° fan about the its nominal viewing (0° deflection) direction. Each pair of sensors, known as the Dual Electron Spectrometer (DES) and the Dual Ion Spectrometer (DIS), occupies a quadrant on the MMS spacecraft and the combination of the eight electron/ion sensors, employing aperture steering, image the full-sky every 30-ms (electrons) and 150-ms (ions), respectively. To probe the diffusion regions of reconnection, the highest temporal/spatial resolution mode of FPI results in the DES complement of a given spacecraft generating 6.5-Mb s-1 of electron data while the DIS generates 1.1-Mb s-1 of ion data yielding an FPI total data rate of 6.6-Mb s-1. The FPI electron/ion data is collected by the IDPU then transmitted to the Central Data Instrument Processor (CIDP) on the spacecraft for science interest ranking. Only data sequences that contain the greatest amount of temporal/spatial structure will be intelligently down-linked by the spacecraft. Currently, the FPI data rate allocation to the CIDP is 1.5-Mb s-1. Consequently, the FPI-IDPU must employ data/image compression to meet this CIDP telemetry allocation. Here, we present updated simulations of the CCSDS 122.0-B-1 algorithm-based compression of the FPI-DES electron data as well as the FPI-DIS ion data. Compression analysis is based upon a seed of re-processed Cluster

  6. Measuring the plasma environment at Mercury: The fast imaging plasma spectrometer

    NASA Astrophysics Data System (ADS)

    Koehn, P. L.; Zurbuchen, T. H.; Gloeckler, G.; Lundgren, R. A.; Fisk, L. A.

    2002-09-01

    The plasma environment at Mercury is a rich laboratory for studying the interaction of the solar wind with a planet. Three primary populations of ions exist at Mercury: solar wind, magnetospheric and pickup ions. These pickup ions are generated through the ionization of Mercury's exosphere or are sputtered particles from the Mercury surface. A comprehensive mission to Mercury, such as MESSENGER, should include a sensor that is able to determine the dynamical properties and composition of all these plasma components. An instrument to measure the composition of these ion populations and their three dimensional velocity distribution functions must be lightweight, fast, and have a very large field of view. The Fast Imaging Plasma Spectrometer (FIPS) is an imaging mass spectrometer, part of NASA's MESSENGER mission, the first Mercury orbiter. This versatile instrument has a very small footprint, and has a mass that is about one order of magnitude less than other comparable systems. It maintains a nearly full-hemisphere field of view, suitable for either spinning or three-axis-stabilized platforms. The major piece of innovation to enable this sensor is a new deflection system geometry that enables a large instantaneous (~1.5() field of view. This novel electrostatic analyzer system is then combined with a position sensitive time-of-flight system. We discuss the design and prototype tests of the FIPS deflection system and show how this system is expected to address one key problem in Mercury science, that of the nature of the radar-bright regions at the Hermean poles.

  7. Plasma turbulence measured with fast frequency swept reflectometry in JET H-mode plasmas

    NASA Astrophysics Data System (ADS)

    Clairet, F.; Sirinelli, A.; Meneses, L.; Contributors, JET

    2016-12-01

    In this work we present recent achievements to provide precise measurements of turbulence on JET H-mode plasmas using frequency sweeping reflectometry diagnostic. The plasma density fluctuations retrieved from swept reflected signals, first initiated with the Tore Supra reflectometry (Heuraux et al 2003 Rev. Sci. Instrum. 74 1501, Vermare et al 2006 Nucl. Fusion 46 S743, Gerbaud et al 2006 Rev. Sci. Instrum. 77 10E928), provides a radial profile of the density fluctuation level and its spectral structure. Using the complete set of the JET X-mode fast sweeping heterodyne reflectometers we have determined the temporal dynamic of the density fluctuation profile from the edge to the center during an H-mode discharge. At the L-H transition, the turbulence reduction seems to occur, at first, simultaneously from the edge to the center then deepens at the edge at ρ ~ 0.95 and this deepening propagates toward the center with a steepening of the wavenumber spectra. During an edge localized mode (ELM) event, a substantial density fluctuations increase has been observed with a localized turbulent wave front propagating toward the center accompanying a particle transport. We also show that type-III ELMs sustain a steady and high level of plasma turbulence compare to type-I.

  8. Reactor shutdown delays medical procedures

    NASA Astrophysics Data System (ADS)

    Gwynne, Peter

    2008-01-01

    A longer-than-expected maintenance shutdown of the Canadian nuclear reactor that produces North America's entire supply of molybdenum-99 - from which the radioactive isotopes technetium-99 and iodine-131 are made - caused delays to the diagnosis and treatment of thousands of seriously ill patients last month. Technetium-99 is a key component of nuclear-medicine scans, while iodine-131 is used to treat cancer and other diseases of the thyroid. Production eventually resumed, but only after the Canadian government had overruled the Canadian Nuclear Safety Commission (CNSC), which was still concerned about the reactor's safety.

  9. Fast Plasma Instrument for MMS: Data Compression Simulation Results

    NASA Technical Reports Server (NTRS)

    Barrie, A.; Adrian, Mark L.; Yeh, P.-S.; Winkert, G. E.; Lobell, J. V.; Vinas, A.F.; Simpson, D. J.; Moore, T. E.

    2008-01-01

    Magnetospheric Multiscale (MMS) mission will study small-scale reconnection structures and their rapid motions from closely spaced platforms using instruments capable of high angular, energy, and time resolution measurements. To meet these requirements, the Fast Plasma Instrument (FPI) consists of eight (8) identical half top-hat electron sensors and eights (8) identical ion sensors and an Instrument Data Processing Unit (IDPU). The sensors (electron or ion) are grouped into pairs whose 6 deg x 180 deg fields-of-view (FOV) are set 90 deg apart. Each sensor is equipped with electrostatic aperture steering to allow the sensor to scan a 45 deg x 180 deg fan about its nominal viewing (0 deg deflection) direction. Each pair of sensors, known as the Dual Electron Spectrometer (DES) and the Dual Ion Spectrometer (DIS), occupies a quadrant on the MMS spacecraft and the combination of the eight electron/ion sensors, employing aperture steering, image the full-sky every 30-ms (electrons) and 150-ms (ions), respectively. To probe the results in the DES complement of a given spacecraft generating 6.5-Mbs(exp -1) of electron data while the DIS generates 1.1-Mbs(exp -1) of ion data yielding an FPI total data rate of 6.6-MBs(exp -1). The FPI electron/ion data is collected by the IDPU then transmitted to the Central Data Instrument Processor (CIDP) on the spacecraft for science interest ranking. Only data sequences that contain the greatest amount of temporal/spatial structure will be intelligently down-linked by the spacecraft. Currently, the FPI data rate allocation to the CIDP is 1.5-Mbs(exp -1). Consequently, the FPI-IDPU must employ data/image compression to meet this CIDP telemetry allocation. Here, we present simulations of the CCSDS 122.0-B-1 algorithm-based compression of the FPI-DES electron data. Compression analysis is based upon a seed of re-processed Cluster/PEACE electron measurements. Topics to be discussed include: review of compression algorithm; data quality

  10. Fast Plasma Instrument for MMS: Data Compression Simulation Results

    NASA Technical Reports Server (NTRS)

    Barrie, A.; Adrian, Mark L.; Yeh, P.-S.; Winkert, G. E.; Lobell, J. V.; Vinas, A.F.; Simpson, D. J.; Moore, T. E.

    2008-01-01

    Magnetospheric Multiscale (MMS) mission will study small-scale reconnection structures and their rapid motions from closely spaced platforms using instruments capable of high angular, energy, and time resolution measurements. To meet these requirements, the Fast Plasma Instrument (FPI) consists of eight (8) identical half top-hat electron sensors and eights (8) identical ion sensors and an Instrument Data Processing Unit (IDPU). The sensors (electron or ion) are grouped into pairs whose 6 deg x 180 deg fields-of-view (FOV) are set 90 deg apart. Each sensor is equipped with electrostatic aperture steering to allow the sensor to scan a 45 deg x 180 deg fan about its nominal viewing (0 deg deflection) direction. Each pair of sensors, known as the Dual Electron Spectrometer (DES) and the Dual Ion Spectrometer (DIS), occupies a quadrant on the MMS spacecraft and the combination of the eight electron/ion sensors, employing aperture steering, image the full-sky every 30-ms (electrons) and 150-ms (ions), respectively. To probe the results in the DES complement of a given spacecraft generating 6.5-Mbs(exp -1) of electron data while the DIS generates 1.1-Mbs(exp -1) of ion data yielding an FPI total data rate of 6.6-MBs(exp -1). The FPI electron/ion data is collected by the IDPU then transmitted to the Central Data Instrument Processor (CIDP) on the spacecraft for science interest ranking. Only data sequences that contain the greatest amount of temporal/spatial structure will be intelligently down-linked by the spacecraft. Currently, the FPI data rate allocation to the CIDP is 1.5-Mbs(exp -1). Consequently, the FPI-IDPU must employ data/image compression to meet this CIDP telemetry allocation. Here, we present simulations of the CCSDS 122.0-B-1 algorithm-based compression of the FPI-DES electron data. Compression analysis is based upon a seed of re-processed Cluster/PEACE electron measurements. Topics to be discussed include: review of compression algorithm; data quality

  11. Fast Plasma Instrument for MMS: Data Compression Simulation Results

    NASA Astrophysics Data System (ADS)

    Barrie, A. C.; Adrian, M. L.; Yeh, P.; Winkert, G. E.; Lobell, J. V.; Viňas, A. F.; Simpson, D. G.; Moore, T. E.

    2008-12-01

    Magnetospheric Multiscale (MMS) mission will study small-scale reconnection structures and their rapid motions from closely spaced platforms using instruments capable of high angular, energy, and time resolution measurements. To meet these requirements, the Fast Plasma Instrument (FPI) consists of eight (8) identical half top-hat electron sensors and eight (8) identical ion sensors and an Instrument Data Processing Unit (IDPU). The sensors (electron or ion) are grouped into pairs whose 6° × 180° fields-of-view (FOV) are set 90° apart. Each sensor is equipped with electrostatic aperture steering to allow the sensor to scan a 45° × 180° fan about the its nominal viewing (0° deflection) direction. Each pair of sensors, known as the Dual Electron Spectrometer (DES) and the Dual Ion Spectrometer (DIS), occupies a quadrant on the MMS spacecraft and the combination of the eight electron/ion sensors, employing aperture steering, image the full-sky every 30-ms (electrons) and 150-ms (ions), respectively. To probe the diffusion regions of reconnection, the highest temporal/spatial resolution mode of FPI results in the DES complement of a given spacecraft generating 6.5-Mb s-1 of electron data while the DIS generates 1.1-Mb s-1 of ion data yielding an FPI total data rate of 7.6-Mb s-1. The FPI electron/ion data is collected by the IDPU then transmitted to the Central Data Instrument Processor (CIDP) on the spacecraft for science interest ranking. Only data sequences that contain the greatest amount of temporal/spatial structure will be intelligently down-linked by the spacecraft. Currently, the FPI data rate allocation to the CIDP is 1.5-Mb s-1. Consequently, the FPI-IDPU must employ data/image compression to meet this CIDP telemetry allocation. Here, we present simulations of the CCSDS 122.0-B-1 algorithm- based compression of the FPI-DES electron data. Compression analysis is based upon a seed of re- processed Cluster/PEACE electron measurements. Topics to be

  12. The FY2014 Government Shutdown: Economic Effects

    DTIC Science & Technology

    2013-11-01

    11 Jeffrey Jones, “U.S. Economic Confidence Continues to Slide Amid Shutdown,” Gallup Economy, October 15... Sachs initially predicted that the shutdown would reduce quarterly growth by 0.2 percentage points per week of its duration. After DOD recalled...furloughed workers, Goldman Sachs reduced its estimate to 0.14 percentage points per week for the remainder of the shutdown.32 They predicted that

  13. Spectroscopic interpretation and velocimetry analysis of fluctuations in a cylindrical plasma recorded by a fast camera

    SciTech Connect

    Oldenbuerger, S.; Brandt, C.; Brochard, F.; Lemoine, N.; Bonhomme, G.

    2010-06-15

    Fast visible imaging is used on a cylindrical magnetized argon plasma produced by thermionic discharge in the Mirabelle device. To link the information collected with the camera to a physical quantity, fast camera movies of plasma structures are compared to Langmuir probe measurements. High correlation is found between light fluctuations and plasma density fluctuations. Contributions from neutral argon and ionized argon to the overall light intensity are separated by using interference filters and a light intensifier. Light emitting transitions are shown to involve a metastable neutral argon state that can be excited by thermal plasma electrons, thus explaining the good correlation between light and density fluctuations. The propagation velocity of plasma structures is calculated by adapting velocimetry methods to the fast camera movies. The resulting estimates of instantaneous propagation velocity are in agreement with former experiments. The computation of mean velocities is discussed.

  14. Fast magnetic field penetration into low resistivity plasma

    NASA Astrophysics Data System (ADS)

    Fruchtman, Amnon

    2017-02-01

    Penetration of a magnetic field into plasma that is faster than resistive diffusion can be induced by the Hall electric field in a non-uniform plasma. This mechanism explained successfully the measured velocity of the magnetic field penetration into pulsed plasmas. Major related issues have not yet been resolved. Such is the theoretically predicted, but so far not verified experimentally, high magnetic energy dissipation, as well as the correlation between the directions of the density gradient and of the field penetration.

  15. Fast ion beta limit measurements by collimated neutron detection in MST plasmas

    NASA Astrophysics Data System (ADS)

    Capecchi, William; Anderson, Jay; Bonofiglo, Phillip; Kim, Jungha; Sears, Stephanie

    2015-11-01

    Fast ion orbits in the reversed field pinch (RFP) are well ordered and classically confined despite magnetic field stochasticity generated by multiple tearing modes. Classical TRANSP modeling of a 1MW tangentially injected hydrogen neutral beam in MST deuterium plasmas predicts a core-localized fast ion density that can be up to 25% of the electron density and a fast ion beta of many times the local thermal beta. However, neutral particle analysis of an NBI-driven mode (presumably driven by a fast ion pressure gradient) shows mode-induced transport of core-localized fast ions and a saturated fast ion density. The TRANSP modeling is presumed valid until the onset of the beam-driven mode and gives an initial estimate of the volume-averaged fast ion beta of 1-2% (local core value up to 10%). A collimated neutron detector for fusion product profile measurements will be used to determine the spatial distribution of fast ions, allowing for a first measurement of the critical fast-ion pressure gradient required for mode destabilization. Testing/calibration data and initial fast-ion profiles will be presented. Characterization of both the local and global fast ion beta will be done for deuterium beam injection into deuterium plasmas for comparison to TRANSP predictions. Work supported by US DOE.

  16. Heating a plasma by a broadband stream of fast electrons: Fast ignition, shock ignition, and Gbar shock wave applications

    SciTech Connect

    Gus’kov, S. Yu.; Nicolai, Ph.; Ribeyre, X.; Tikhonchuk, V. T.

    2015-09-15

    An exact analytic solution is found for the steady-state distribution function of fast electrons with an arbitrary initial spectrum irradiating a planar low-Z plasma with an arbitrary density distribution. The solution is applied to study the heating of a material by fast electrons of different spectra such as a monoenergetic spectrum, a step-like distribution in a given energy range, and a Maxwellian spectrum, which is inherent in laser-produced fast electrons. The heating of shock- and fast-ignited precompressed inertial confinement fusion (ICF) targets as well as the heating of a target designed to generate a Gbar shock wave for equation of state (EOS) experiments by laser-produced fast electrons with a Maxwellian spectrum is investigated. A relation is established between the energies of two groups of Maxwellian fast electrons, which are responsible for generation of a shock wave and heating the upstream material (preheating). The minimum energy of the fast and shock igniting beams as well as of the beam for a Gbar shock wave generation increases with the spectral width of the electron distribution.

  17. Accelerated ions from pulsed-power-driven fast plasma flow in perpendicular magnetic field

    SciTech Connect

    Takezaki, Taichi Takahashi, Kazumasa; Sasaki, Toru Harada, Nob.; Kikuchi, Takashi

    2016-06-15

    To understand the interaction between fast plasma flow and perpendicular magnetic field, we have investigated the behavior of a one-dimensional fast plasma flow in a perpendicular magnetic field by a laboratory-scale experiment using a pulsed-power discharge. The velocity of the plasma flow generated by a tapered cone plasma focus device is about 30 km/s, and the magnetic Reynolds number is estimated to be 8.8. After flow through the perpendicular magnetic field, the accelerated ions are measured by an ion collector. To clarify the behavior of the accelerated ions and the electromagnetic fields, numerical simulations based on an electromagnetic hybrid particle-in-cell method have been carried out. The results show that the behavior of the accelerated ions corresponds qualitatively to the experimental results. Faster ions in the plasma flow are accelerated by the induced electromagnetic fields modulated with the plasma flow.

  18. Gas dynamic theory of flight of fast electron flux in plasma

    NASA Astrophysics Data System (ADS)

    Melnik, V. N.

    The one-dimensional flight of a fast electron flux in plasma is investigated taking into account generation and absorption of plasma waves. The transition from the kinetic description to the gas dynamics is made. The closed set of gas dynamic equations for electrons and plasmons is derived and an automodel solution is obtained in the case of instantaneous injection. This solution represents the beam-plasma formation on natural oscillations in the system electrons+plasmons is considered.

  19. 33 CFR 155.780 - Emergency shutdown.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Emergency shutdown. 155.780..., Procedures, Equipment, and Records § 155.780 Emergency shutdown. (a) A tank vessel with a capacity of 250 or more barrels that is carrying oil or hazardous material as cargo must have on board an emergency means...

  20. 33 CFR 155.780 - Emergency shutdown.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Emergency shutdown. 155.780..., Procedures, Equipment, and Records § 155.780 Emergency shutdown. (a) A tank vessel with a capacity of 250 or more barrels that is carrying oil or hazardous material as cargo must have on board an emergency means...

  1. 33 CFR 155.780 - Emergency shutdown.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Emergency shutdown. 155.780..., Procedures, Equipment, and Records § 155.780 Emergency shutdown. (a) A tank vessel with a capacity of 250 or more barrels that is carrying oil or hazardous material as cargo must have on board an emergency means...

  2. 33 CFR 155.780 - Emergency shutdown.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Emergency shutdown. 155.780..., Procedures, Equipment, and Records § 155.780 Emergency shutdown. (a) A tank vessel with a capacity of 250 or more barrels that is carrying oil or hazardous material as cargo must have on board an emergency means...

  3. Optical emission spectroscopy observations of fast pulsed capillary discharge plasmas

    NASA Astrophysics Data System (ADS)

    Avaria, G.; Ruiz, M.; Guzmán, F.; Favre, M.; Wyndham, E. S.; Chuaqui, H.; Bhuyan, H.

    2014-05-01

    We present time resolved optical emission spectroscopic (OES) observations of a low energy, pulsed capillary discharage (PCD). The optical emission from the capillary plasma and plasma jets emitted from the capillary volume was recorded with with a SpectraPro 275 spectrograph, fitted with a MCP gated OMA system, with 15 ns time resolution. The discharge was operated with different gases, including argon, nitrogen, hydrogen and methane, in a repetitive pulsed discharge mode at 10-50 Hz, with, 10-12 kV pulses applied at the cathode side. The time evolution of the electron density was measured using Stark broadening of the Hβ line. Several features of the capillary plasma dynamics, such as ionization growth, wall effects and plasma jet evolution, are inferred from the time evolution of the optical emission.

  4. Fasting reduces plasma proprotein convertase, subtilisin/kexin type 9 and cholesterol biosynthesis in humans

    PubMed Central

    Browning, Jeffrey D.; Horton, Jay D.

    2010-01-01

    Proprotein convertase, subtilisin/kexin type 9 (PCSK9), a key regulator of plasma LDL-cholesterol (LDL-c) and cardiovascular risk, is produced in liver and secreted into plasma where it binds hepatic LDL receptors (LDLR), leading to their degradation. PCSK9 is transcriptionally activated by sterol response element-binding protein (SREBP)-2, a transcription factor that also activates all genes for cholesterol synthesis as well as the LDLR. Here we investigated the relationship between plasma PCSK9 levels and the lathosterol-to-cholesterol ratio, a marker of cholesterol biosynthesis, in 18 healthy subjects during a 48 h fast. In all individuals, plasma PCSK9 levels declined steadily during the fasting period, reaching a nadir at 36 h that was ∼58% lower than levels measured in the fed state (P < 0.001). Similarly, the lathosterol-to-cholesterol ratio declined in parallel with plasma PCSK9 concentrations during the fast, reaching a nadir at 36 h that was ∼28% lower than that measured in the fed state (P = 0.024). In summary, fasting has a marked effect on plasma PCSK9 concentrations, which is mirrored by measures of cholesterol synthesis in humans. Inasmuch as cholesterol synthesis and PCSK9 are both regulated by SREBP-2, these results suggest that plasma PCSK9 levels may serve as a surrogate marker of hepatic SREBP-2 activity in humans. PMID:20716520

  5. Dynamical programming based turbulence velocimetry for fast visible imaging of tokamak plasma

    NASA Astrophysics Data System (ADS)

    Banerjee, Santanu; Zushi, H.; Nishino, N.; Mishra, K.; Onchi, T.; Kuzmin, A.; Nagashima, Y.; Hanada, K.; Nakamura, K.; Idei, H.; Hasegawa, M.; Fujisawa, A.

    2015-03-01

    An orthogonal dynamic programming (ODP) based particle image velocimetry (PIV) technique is developed to measure the time resolved flow field of the fluctuating structures at the plasma edge and scrape off layer (SOL) of tokamaks. This non-intrusive technique can provide two dimensional velocity fields at high spatial and temporal resolution from a fast framing image sequence and hence can provide better insights into plasma flow as compared to conventional probe measurements. Applicability of the technique is tested with simulated image pairs. Finally, it is applied to tangential fast visible images of QUEST plasma to estimate the SOL flow in inboard poloidal null-natural divertor configuration. This technique is also applied to investigate the intricate features of the core of the run-away dominated phase following the injection of a large amount of neutrals in the target Ohmic plasma. Development of the ODP-PIV code and its applicability on actual plasma images is reported.

  6. Fast electron generation and transport in a turbulent, magnetized plasma

    SciTech Connect

    Stoneking, Matthew Randall

    1994-05-01

    The nature of fast electron generation and transport in the Madison Symmetric Torus (MST) reversed field pinch (RFP) is investigated using two electron energy analyzer (EEA) probes and a thermocouple calorimeter. The parallel velocity distribution of the fast electron population is well fit by a drifted Maxwellian distribution with temperature of about 100 eV and drift velocity of about 2 x 106 m/s. Cross-calibration of the EEA with the calorimeter provides a measurement of the fast electron perpendicular temperature of 30 eV, much lower than the parallel temperature, and is evidence that the kinetic dynamo mechanism (KDT) is not operative in MST. The fast electron current is found to match to the parallel current at the edge, and the fast electron density is about 4 x 1011 cm-3 independent of the ratio of the applied toroidal electric field to the critical electric field for runaways. First time measurements of magnetic fluctuation induced particle transport are reported. By correlating electron current fluctuations with radial magnetic fluctuations the transported flux of electrons is found to be negligible outside r/a~0.9, but rises the level of the expected total particle losses inside r/a~0.85. A comparison of the measured diffusion coefficient is made with the ausilinear stochastic diffusion coefficient. Evidence exists that the reduction of the transport is due to the presence of a radial ambipolar electric field of magnitude 500 V/m, that acts to equilibrate the ion and electron transport rates. The convective energy transport associated with the measured particle transport is large enough to account for the observed magnetic fluctuation induced energy transport in MST.

  7. Emission of fast non-Maxwellian hydrogen atoms in low-density laboratory plasma

    NASA Astrophysics Data System (ADS)

    Brandt, Christian; Marchuk, Oleksandr; Pospieszczyk, Albrecht; Dickheuer, Sven

    2017-03-01

    The source of strong and broad emission of the Balmer-α line in mixed plasmas of hydrogen (or deuterium) and noble gases in front of metallic surfaces is a subject of controversial discussion of many plasma types. In this work the excitation source of the Balmer lines is investigated by means of optical emission spectroscopy in the plasma device PSI-2. Neutral fast non-Maxwellian hydrogen atoms are produced by acceleration of hydrogen ions towards an electrode immersed into the plasma. By variation of the electrode potential the energy of ions and in turn of reflected fast atoms can be varied in the range of 40-300 eV. The fast atoms in front of the electrode are observed simultaneously by an Echelle spectrometer (0.001 nm/channel) and by an imaging spectrometer (0.01 nm/channel) up to few cm in the plasma. Intense excitation channels of the Balmer lines are observed when hydrogen is mixed with argon or with krypton. Especially in Ar-H and Ar-D mixed plasmas the emission of fast hydrogen atoms is very strong. Intermixing hydrogen with other noble gases (He, Ne or Xe) one observes the same effect however the emission is one order of magnitude less compared to Kr-H or Kr-D plasmas. It is shown, that the key process, impacting this emission, is the binary collision between the fast neutral hydrogen atom and the noble gas atom. Two possible sources of excitation are discussed in details: one is the excitation of hydrogen atoms by argon atoms in the ground state and the second one is the process of the so-called excitation transfer between the metastable states of noble gases and hydrogen. In the latter case the atomic data for excitation of Balmer lines are still not available in literature. Further experimental investigations are required to conclude on the source process of fast atom emission.

  8. Communication through a plasma sheet around a fast moving vehicle

    NASA Astrophysics Data System (ADS)

    Sotnikov, V. I.; Mudaliar, S.; Genoni, T.; Rose, D.; Oliver, B. V.; Mehlhorn, T. A.

    2011-10-01

    Investigation of the complicated problem of scattering of electromagnetic waves on turbulent pulsations induced by a sheared flow inside a plasma sheath is important for many applications including communication with hypersonic and re-entry vehicles. Theoretical and computational work aimed at improving the understanding of electromagnetic wave scattering processes in such turbulent plasmas is presented. We analyze excitation of low frequency ion-acoustic type oscillations in a compressible plasma flow with flow velocity shear and influence of such turbulent pulsations on scattering of high frequency electromagnetic waves used for communication purposes. We have appropriately included in our analysis the presence of electron and ion collisions with neutrals as well as electron - ion collisions. Results of numerical solutions for plasma density and electric field perturbations for different velocity profiles have been used in the derived expressions for scattered wave energy and scattering cross section. Work supported by the Air Force Research Laboratory and Air Force Office Of Scientific Research Sandia is a multiprogram laboratory operated by Sandia Corporation, A Lockheed Martin Company, under contract DE-AC04-94AL85000.

  9. Relationship between gestational fasting plasma glucose and neonatal birth weight, prenatal blood pressure and dystocia in pregnant Chinese women.

    PubMed

    Zhu, Min; Cai, Jing; Liu, Shujuan; Huang, Mingwei; Chen, Yao; Lai, Xiaolan; Chen, Yuyu; Zhao, Zhongwen; Wu, Fangzhen; Wu, Dongmei; Miu, Haiyan; Lai, Shenghan; Chen, Gang

    2014-09-01

    Little is known about the optimal cut-off point of fasting plasma glucose for the diagnosis of gestational diabetes mellitus for pregnant Chinese women. This study investigates the relationship between gestational fasting plasma glucose and several variables: neonatal birth weight, prenatal blood pressure and dystocia rate of pregnant women. In this study, we hoped to provide a useful tool to screen gestational diabetes mellitus in pregnant Chinese women. For 1058 pregnant women enrolled in our hospital at pregnancy weeks 22-30, fasting plasma glucose, neonatal birth weight and prenatal blood pressure, as well as dystocia conditions, were examined. We analysed the correlations between the following: gestational fasting plasma glucose and neonatal birth weight; prenatal blood pressure and gestational fasting plasma glucose as well as dystocia rate and gestational fasting plasma glucose group. A modest correlation was observed between gestational fasting plasma glucose and neonatal birth weight (r = 0.093, p = 0.003). The macrosomia rate was smallest when the gestational fasting plasma glucose was in the range 3.51-5.5 mmol/L. Prenatal blood pressure increased linearly with increasing gestational fasting plasma glucose (p = 0.000). There was a significant difference between the dystocia rates in different fasting plasma glucose groups (chi-squared = 13.015, p = 0.043). The results showed that the dystocia rate significantly increased when gestational fasting plasma glucose was >4.9 mmol/L; p = 0.03, OR = 2.156 (95% CI, 1.077-4.318). We suggest that the optimal range of gestational fasting plasma glucose for pregnant Chinese women is in the range 3.5-4.9 mmol/L. Copyright © 2014 John Wiley & Sons, Ltd.

  10. Plasma Concentrations of Digoxin after Oral Administration in the Fasting and Postprandial State

    PubMed Central

    White, R. J.; Chamberlain, D. A.; Howard, M.; Smith, T. W.

    1971-01-01

    After the oral administration of 0·5 mg of digoxin in tablet form to fasting subjects peak plasma levels were reached in 30 to 60 minutes. Levels then fell to reach a plateau at six to eight hours. When the same dose was given after food the peak plasma concentrations were significantly lower, but the concentrations reached in samples obtained from two to eight hours after the dose did not differ appreciably from corresponding samples obtained in the fasting experiments. In a four-week cross-over study of 21 patients on maintenance therapy, digoxin taken regularly in the fasting state produced plasma concentrations similar to those obtained when the drug was taken after meals. The rapid appearance of digoxin in the blood suggests that the oral route of administration is adequate for most patients who require rapid digitalization, and the timing of maintenance dosage in relation to meals is unimportant. PMID:5100372

  11. Fast figuring of large optics by reactive atom plasma

    NASA Astrophysics Data System (ADS)

    Castelli, Marco; Jourdain, Renaud; Morantz, Paul; Shore, Paul

    2012-09-01

    The next generation of ground-based astronomical observatories will require fabrication and maintenance of extremely large segmented mirrors tens of meters in diameter. At present, the large production of segments required by projects like E-ELT and TMT poses time frames and costs feasibility questions. This is principally due to a bottleneck stage in the optical fabrication chain: the final figuring step. State-of-the-art figure correction techniques, so far, have failed to meet the needs of the astronomical community for mass production of large, ultra-precise optical surfaces. In this context, Reactive Atom Plasma (RAP) is proposed as a candidate figuring process that combines nanometer level accuracy with high material removal rates. RAP is a form of plasma enhanced chemical etching at atmospheric pressure based on Inductively Coupled Plasma technology. The rapid figuring capability of the RAP process has already been proven on medium sized optical surfaces made of silicon based materials. In this paper, the figure correction of a 3 meters radius of curvature, 400 mm diameter spherical ULE mirror is presented. This work demonstrates the large scale figuring capability of the Reactive Atom Plasma process. The figuring is carried out by applying an in-house developed procedure that promotes rapid convergence. A 2.3 μm p-v initial figure error is removed within three iterations, for a total processing time of 2.5 hours. The same surface is then re-polished and the residual error corrected again down to λ/20 nm rms. These results highlight the possibility of figuring a metre-class mirror in about ten hours.

  12. Nonlinear m = 1 mode and fast reconnection in collisional plasmas

    SciTech Connect

    Aydemir, A.Y.

    1997-02-01

    Time evolution of the m = 1 resistive kink mode is shown to be compromised of two exponential growth phases separated by a transition period during which the growth becomes temporarily algebraic. A modified Sweet-Parker model that takes into account some of the changes in the geometry of the core plasma and the growing island is offered to explain the departure from the algebraic growth of the early nonlinear phase.

  13. Nonlinear m = 1 Mode and Fast Reconnection in Collisional Plasmas

    NASA Astrophysics Data System (ADS)

    Aydemir, A. Y.

    1997-06-01

    Time evolution of the m = 1 resistive kink mode is shown to be comprised of two exponential growth phases separated by a transition period during which the growth becomes temporarily algebraic. A modified Sweet-Parker model that takes into account some of the changes in the geometry of the core plasma and the growing island is offered to explain the departure from the algebraic growth of the early nonlinear phase.

  14. First experimental demonstration of magnetic-field assisted fast heating of a dense plasma core

    NASA Astrophysics Data System (ADS)

    Fujioka, Shinsuke; Sakata, Shohei; Lee, Seung Ho; Matsuo, Kazuki; Sawada, Hiroshi; Iwasa, Yuki; Law, King Fai Farley; Morita, Hitoki; Kojima, Sadaoki; Abe, Yuki; Yao, Akira; Hata, Masayasu; Johzaki, Tomoyuki; Sunahara, Atsushi; Ozaki, Tetsuo; Sakagami, Hitoshi; Morace, Alessio; Arikawa, Yasunobu; Yogo, Akifumi; Nishimura, Hiroaki; Nakai, Mitsuo; Shiraga, Hiroyuki; Sentoku, Yasuhiko; Nagatomo, Hideo; Azechi, Hiroshi; Firex Project Team

    2016-10-01

    Fast heating of a dense plasma core by an energetic electron beam is being studied on GEKKO-LFEX laser facility. Here, we introduce a laser-driven kilo-tesla external magnetic field to guide the diverging electron beam to the dense plasma core. This involve placing a spherical target in the magnetic field, compressing it with the GEKKO-XII laser beams and then using the LFEX laser beams injected into the dense plasma to generate the electron beam which do the fast heating. Cu-Ka emission is used to visualize transport or heating processes of a dense plasma. X-ray spectrum from a highly ionized Cu ions indicates several keV of the temperature increment induced by the LFEX.

  15. Elevated Fasting Plasma Glucose before Liver Transplantation is Associated with Lower Post-Transplant Survival

    PubMed Central

    Katsura, Emi; Ichikawa, Tatsuki; Taura, Naota; Miyaaki, Hisamitsu; Miuma, Satoshi; Shibata, Hidetaka; Honda, Takuya; Hidaka, Masaaki; Soyama, Akihiko; Takeshima, Fuminao; Eguchi, Susumu; Nakao, Kazuhiko

    2016-01-01

    Background The risk of liver cirrhosis is higher among individuals with diabetes mellitus, and a cirrhotic patient with diabetes may have a poorer prognosis after liver transplantation compared to a patient without diabetes. Thus, we evaluated whether fasting plasma glucose prior to receiving a liver transplant was a prognostic factor for post-transplant survival. Material/Methods Ninety-one patients received a living donor liver transplant between November 2005 and December 2012. Patients were considered diabetic if they were prescribed diabetes medications or had impaired glucose tolerance as measured by an oral glucose tolerance test. Each patient was monitored through December 31, 2013, to evaluate prognosis. Results Fasting plasma glucose of at least 100 mg/dL significantly decreased survival following transplant (52% in the high FPG group compared to 78% in the control group, p=0.04), while postprandial hyperglycemia had no effect on survival. Additionally, overall mortality and the incidence of vascular disease were significantly higher among patients with uncontrolled plasma glucose. Impaired fasting plasma glucose was significantly and inversely associated with overall survival in the univariate and multivariate analyses, while creatinine (at least 1 mg/dL) was inversely associated with survival in the univariate analysis. Conclusions Elevated fasting plasma glucose prior to liver transplantation was inversely associated with post-transplant survival. This effect may be due to underlying microangiopathy as a result of uncontrolled diabetes before transplantation. Our data demonstrated the importance of controlled blood glucose prior to liver transplantation. PMID:27909287

  16. Arbitrary amplitude fast electron-acoustic solitons in three-electron component space plasmas

    SciTech Connect

    Mbuli, L. N.; Maharaj, S. K.; Bharuthram, R.; Singh, S. V.; Lakhina, G. S.

    2016-06-15

    We examine the characteristics of fast electron-acoustic solitons in a four-component unmagnetised plasma model consisting of cool, warm, and hot electrons, and cool ions. We retain the inertia and pressure for all the plasma species by assuming adiabatic fluid behaviour for all the species. By using the Sagdeev pseudo-potential technique, the allowable Mach number ranges for fast electron-acoustic solitary waves are explored and discussed. It is found that the cool and warm electron number densities determine the polarity switch of the fast electron-acoustic solitons which are limited by either the occurrence of fast electron-acoustic double layers or warm and hot electron number density becoming unreal. For the first time in the study of solitons, we report on the coexistence of fast electron-acoustic solitons, in addition to the regular fast electron-acoustic solitons and double layers in our multi-species plasma model. Our results are applied to the generation of broadband electrostatic noise in the dayside auroral region.

  17. ACS SBC Recovery from Anomalous Shutdown

    NASA Astrophysics Data System (ADS)

    Wheeler, Thomas

    2010-09-01

    This proposal is designed to permit recovery of the SBC {FUV MAMA} detector after an anomalous shutdown. Anomalous shutdowns can occur as a result of bright object violations which trigger the Bright Scene Detection or Software Global Monitor. Anomalous shutdowns can also occur as a result of SBC hardware problems. The recovery from anomalous shutdown procedure consists of four tests: a signal processing electronics check, a slow high voltage ramp-up to an intermediate voltage, a slow high-voltage ramp-up to the full operating voltage, and lastly, a Fold Test. During the two high-voltage ramp-ups, dark ACCUM exposures are taken. At high voltage, dark ACCUM exposures and diagnostics are taken. This proposal is based on proposal 11884, visits 1 to 4.

  18. ACS SBC Recovery from Anomalous Shutdown

    NASA Astrophysics Data System (ADS)

    Wheeler, Thomas

    2012-10-01

    This proposal is designed to permit recovery of the SBC {FUV MAMA} detector after an anomalous shutdown. Anomalous shutdowns can occur as a result of bright object violations which trigger the Bright Scene Detection or Software Global Monitor. Anomalous shutdowns can also occur as a result of SBC hardware problems. The recovery from anomalous shutdown procedure consists of four tests: 1} a signal processing electronics check, 2} a slow high voltage ramp-up to an intermediate voltage, 3} a slow high-voltage ramp-up to the full operating voltage, and 4} a Fold Test. During the two high-voltage ramp-ups, dark ACCUM exposures are taken. At high voltage, dark ACCUM exposures and diagnostics are taken. This proposal is based on Proposal 12738 from Cycle 19.

  19. Perspectives on Low Power and Shutdown Risk

    SciTech Connect

    CAMP,ALLEN L.; WHITEHEAD,DONNIE W.; WHEELER,TIMOTHY A.; LEHNER,JOHN; CHU,TSONG-LUN; LOIS,ERASMAI; DROUIN,MARY

    2000-07-06

    This paper presents results from a program sponsored by the US Nuclear Regulatory Commission to examine the risks from low power and shutdown operations. Significant progress has been made by the industry in reducing such risks; however, important operational events continue to occur. Current perceptions of low power and shutdown risks are discussed in the paper along with an assessment of the current methods for understanding important events and quantifying their associated risk.

  20. Evaluation of plasma and buffy coat ascorbic acid concentrations in dogs before and after a 24-hour fast.

    PubMed

    Lee, A H; Spano, J S; Swaim, S F; McGuire, J A; Hughes, K S

    1986-09-01

    Samples of blood were taken from 15 female and 15 male research laboratory Beagles before and after they were fasted for 24 hours. The mean buffy coat ascorbic acid concentration was significantly higher in dogs after they were fasted than that before they were fasted. In contrast, the mean plasma ascorbic acid concentration was significantly lower in dogs after they were fasted than that before they were fasted. The mean buffy coat ascorbic acid concentrations in blood samples of both fasted and nonfasted female Beagles was significantly greater than those of male Beagles, whereas the mean plasma concentrations of both fasted and nonfasted female Beagles was significantly lower than those of male Beagles. It was observed that whenever there was a decrease in plasma ascorbic acid concentration, there was an increase in buffy coat ascorbic acid concentration, regardless of fasting stress or sex difference.

  1. Integrated Kinetic Simulation of Laser-Plasma Interactions, Fast-Electron Generation and Transport in Fast Ignition

    SciTech Connect

    Kemp, A; Cohen, B; Divol, L

    2009-11-16

    We present new results on the physics of short-pulse laser-matter interaction of kilojoule-picosecond pulses at full spatial and temporal scale, using a new approach that combines a 3D collisional electromagnetic Particle-in-Cell code with an MHD-hybrid model of high-density plasma. In the latter, collisions damp out plasma waves, and an Ohm's law with electron inertia effects neglected determines the electric field. In addition to yielding orders of magnitude in speed-up while avoiding numerical instabilities, this allows us to model the whole problem in a single unified framework: the laser-plasma interaction at sub-critical densities, energy deposition at relativistic critical densities, and fast-electron transport in solid densities. Key questions such as the multi-picosecond temporal evolution of the laser energy conversion into hot electrons, the impact of return currents on the laser-plasma interaction, and the effect of self-generated electric and magnetic fields on electron transport will be addressed. We will report applications to current experiments.

  2. Integrated kinetic simulation of laser-plasma interactions, fast-electron generation, and transport in fast ignition

    SciTech Connect

    Kemp, A. J.; Cohen, B. I.; Divol, L.

    2010-05-15

    We present new results on the physics of short-pulse laser-matter interaction of kilojoule-picosecond pulses at full spatial and temporal scale using a new approach that combines a three-dimensional collisional electromagnetic particle-in-cell code with a magnetohydrodynamic-hybrid model of high-density plasma. In the latter, collisions damp out plasma waves, and an Ohm's law with electron inertia effects neglected determines the electric field. In addition to yielding orders of magnitude in speed-up while avoiding numerical instabilities, this allows us to model the whole problem in a single unified framework: the laser-plasma interaction at subcritical densities, energy deposition at relativistic critical densities, and fast- electron transport in solid densities. Key questions such as the multipicosecond temporal evolution of the laser energy conversion into hot electrons, the impact of return currents on the laser-plasma interaction, and the effect of self-generated electric and magnetic fields on electron transport will be addressed. We will report applications to current experiments.

  3. Fast tokamak plasma flux and electron density reconstruction technique

    SciTech Connect

    Chiang, K.L.; Hallock, G.A.; Wootton, A.J.; Wang, L.

    1997-01-01

    Density profiles in TEXT-U are obtained using a vertical viewing far-infrared (FIR) interferometer. To obtain the local (inverted) density, we have developed a simple analytic model of the plasma equilibrium configuration which is faster than EFIT (a flux surface reconstruction program) and can be easily computed between discharges. This analytic solution of the Grad{endash}Shafranov equation is valid as long as the pressure p is a function of poloidal flux {psi}, i.e., p=p({psi}). The procedure incorporates both magnetic and FIR density data to solve the Grad{endash}Shafranov equation, and provides a density profile which is self-consistent with the reconstructed equilibrium flux surfaces. Examples are presented. {copyright} {ital 1997 American Institute of Physics.}

  4. 40 CFR 63.1111 - Startup, shutdown, and malfunction.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Startup, shutdown, and malfunction. 63... Control Technology Standards § 63.1111 Startup, shutdown, and malfunction. (a) Startup, shutdown, and... develop a written startup, shutdown, and malfunction plan that describes, in detail, procedures...

  5. Diagnostic value of the rectal ammonia tolerance test, fasting plasma ammonia and fasting plasma bile acids for canine portosystemic shunting.

    PubMed

    van Straten, G; Spee, B; Rothuizen, J; van Straten, M; Favier, R P

    2015-06-01

    Portosystemic shunting (PSS) often results in hyperammonaemia and, consequently, hepatic encephalopathy. This retrospective study evaluated the sensitivity, specificity, positive and negative predictive values (PPV and NPV, respectively) and other test performance metrics for the ammonia tolerance test (ATT), serum fasting bile acids (FBA), serum fasting ammonia concentration (FA), and combinations of these tests for their association with PSS in dogs. Medical records of 271 dogs suspect for PSS (symptomatic group) and 53 dogs returning for evaluation after surgical closure of a congenital PSS (CPSS post-surgical control group) were analysed. In the symptomatic group, ATT at 40 min (T40), and the FBA had the highest sensitivity (100% and 98%, respectively) and NPV (100% and 96%, respectively) for PSS. The combination of increased FBA and FA had the highest specificity (97%), with a PPV of 97%, and a positive likelihood ratio of 29. In the CPSS post-surgical control group, the specificity and PPV of FA and the combination of increased FBA/FA were both 100%. In purebred populations, the NPV of all tests was 100%. Consequently, PSS would be ruled out in a symptomatic dog with normal FBA or ATT (T40) and would be highly probable when both FBA and FA are increased. Increased FA was conclusive for PSS in dogs evaluated for post-surgical closure of a CPSS. FBA was the most suitable test for screening purposes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. The role of curvature and stretching on the existence of fast dynamo plasma in Riemannian space

    SciTech Connect

    Garcia de Andrade, L. C.

    2008-12-15

    Vishik's anti-dynamo theorem is applied to a nonstretched twisted magnetic flux tube in Riemannian space. Marginal or slow dynamos along curved (folded), torsioned (twisted), and nonstretching flux tubes plasma flows are obtained. Riemannian curvature of the twisted magnetic flux tube is computed in terms of the Frenet curvature in the thin tube limit. It is shown that, for nonstretched filaments, fast dynamo action in the diffusive case cannot be obtained, in agreement with Vishik's argument that fast dynamos cannot be obtained in nonstretched flows. Instead of a fast dynamo, a nonuniform stretching slow dynamo is obtained. An example is given, which generalizes plasma dynamo laminar flows, recently presented by Wang et al. [Phys Plasmas 9, 1491 (2002)], in the case of low magnetic Reynolds number Re{sub m}{>=}210. Curved and twisting Riemannian heliotrons, where nondynamo modes are found even when stretching is present, shows that the simple presence of stretching is not enough for the existence of dynamo action. In this paper, folding plays the role of Riemannian curvature and can be used to cancel magnetic fields, not enhancing the dynamo action. Nondynamo modes are found for certain values of torsion, or Frenet curvature (folding) in the spirit of the anti-dynamo theorem. It is also shown that curvature and stretching are fundamental for the existence of fast dynamos in plasmas.

  7. Fast-acting calorimeter measures heat output of plasma gun accelerator

    NASA Technical Reports Server (NTRS)

    Dethlefson, R.; Larson, A. V.; Liebing, L.

    1967-01-01

    Calorimeter measures the exhaust energy from a shot of a pulsed plasma gun accelerator. It has a fast response time and requires only one measurement to determine the total energy. It uses a long ribbon of copper foil wound around a glass frame to form a reentrant cavity.

  8. Newly developed double neural network concept for reliable fast plasma position control

    NASA Astrophysics Data System (ADS)

    Jeon, Young-Mu; Na, Yong-Su; Kim, Myung-Rak; Hwang, Y. S.

    2001-01-01

    Neural network is considered as a parameter estimation tool in plasma controls for next generation tokamak such as ITER. The neural network has been reported to be so accurate and fast for plasma equilibrium identification that it may be applied to the control of complex tokamak plasmas. For this application, the reliability of the conventional neural network needs to be improved. In this study, a new idea of double neural network is developed to achieve this. The new idea has been applied to simple plasma position identification of KSTAR tokamak for feasibility test. Characteristics of the concept show higher reliability and fault tolerance even in severe faulty conditions, which may make neural network applicable to plasma control reliably and widely in future tokamaks.

  9. Ultra-Fast Pump-Probe Detection Using Plasmas

    SciTech Connect

    Tatchyn, R.; /SLAC

    2006-02-17

    The temporal resolution of pump-flash interactions in the femtosecond-attosecond (fs-as) regime is limited by the characteristic time constants of the excited states in the detector material. If the relaxation time constant is appreciably longer that the time interval between the pump and probe signals the response of the detector material to the probe represents a temporal convolution with the pump and probe responses, setting a lower limit on the resolution to which the interval between the two pulses can be measured. In most of the solid state ultrafast detection schemes that are being considered for the ultrashort pulse x-ray sources under current development at SLAC and elsewhere the characteristic time constants are related to the bound states of the atoms comprising the material or to the relaxation times of phase transitions or charge carrier populations of the lattice, setting a probable lower limit on the attainable resolution on the order of {approx}0.1 ps. In this paper we consider a novel detection principle based on the excitation of specially prepared unbound states in an ionized plasma with high pump and probe fields, and estimate its potential for extending the lower limit of resolution into the attosecond (as) regime.

  10. Fast wave current drive in neutral beam heated plasmas on DIII-D

    SciTech Connect

    Petty, C.C.; Forest, C.B.; Pinsker, R.I.

    1997-04-01

    The physics of non-inductive current drive and current profile control using the fast magnetosonic wave has been demonstrated on the DIII-D tokamak. In non-sawtoothing discharges formed by neutral beam injection (NBI), the radial profile of the fast wave current drive (FWCD) was determined by the response of the loop voltage profile to co, counter, and symmetric antenna phasings, and was found to be in good agreement with theoretical models. The application of counter FWCD increased the magnetic shear reversal of the plasma and delayed the onset of sawteeth, compared to co FWCD. The partial absorption of fast waves by energetic beam ions at high harmonics of the ion cyclotron frequency was also evident from a build up of fast particle pressure near the magnetic axis and a correlated increase in the neutron rate. The anomalous fast particle pressure and neutron rate increased with increasing NBI power and peaked when a harmonic of the deuterium cyclotron frequency passed through the center of the plasma. The experimental FWCD efficiency was highest at 2 T where the interaction between the fast waves and the beam ions was weakest; as the magnetic field strength was lowered, the FWCD efficiency decreased to approximately half of the maximum theoretical value.

  11. Heating efficiency evaluation with mimicking plasma conditions of integrated fast-ignition experiment.

    PubMed

    Fujioka, Shinsuke; Johzaki, Tomoyuki; Arikawa, Yasunobu; Zhang, Zhe; Morace, Alessio; Ikenouchi, Takahito; Ozaki, Tetsuo; Nagai, Takahiro; Abe, Yuki; Kojima, Sadaoki; Sakata, Shohei; Inoue, Hiroaki; Utsugi, Masaru; Hattori, Shoji; Hosoda, Tatsuya; Lee, Seung Ho; Shigemori, Keisuke; Hironaka, Youichiro; Sunahara, Atsushi; Sakagami, Hitoshi; Mima, Kunioki; Fujimoto, Yasushi; Yamanoi, Kohei; Norimatsu, Takayoshi; Tokita, Shigeki; Nakata, Yoshiki; Kawanaka, Junji; Jitsuno, Takahisa; Miyanaga, Noriaki; Nakai, Mitsuo; Nishimura, Hiroaki; Shiraga, Hiroyuki; Nagatomo, Hideo; Azechi, Hiroshi

    2015-06-01

    A series of experiments were carried out to evaluate the energy-coupling efficiency from heating laser to a fuel core in the fast-ignition scheme of laser-driven inertial confinement fusion. Although the efficiency is determined by a wide variety of complex physics, from intense laser plasma interactions to the properties of high-energy density plasmas and the transport of relativistic electron beams (REB), here we simplify the physics by breaking down the efficiency into three measurable parameters: (i) energy conversion ratio from laser to REB, (ii) probability of collision between the REB and the fusion fuel core, and (iii) fraction of energy deposited in the fuel core from the REB. These three parameters were measured with the newly developed experimental platform designed for mimicking the plasma conditions of a realistic integrated fast-ignition experiment. The experimental results indicate that the high-energy tail of REB must be suppressed to heat the fuel core efficiently.

  12. A new equation in two dimensional fast magnetoacoustic shock waves in electron-positron-ion plasmas

    SciTech Connect

    Masood, W.; Jehan, Nusrat; Mirza, Arshad M.

    2010-03-15

    Nonlinear properties of the two dimensional fast magnetoacoustic waves are studied in a three-component plasma comprising of electrons, positrons, and ions. In this regard, Kadomtsev-Petviashvili-Burger (KPB) equation is derived using the small amplitude perturbation expansion method. Under the condition that the electron and positron inertia are ignored, Burger-Kadomtsev-Petviashvili (Burger-KP) for a fast magnetoacoustic wave is derived for the first time, to the best of author's knowledge. The solutions of both KPB and Burger-KP equations are obtained using the tangent hyperbolic method. The effects of positron concentration, kinematic viscosity, and plasma beta are explored both for the KPB and the Burger-KP shock waves and the differences between the two are highlighted. The present investigation may have relevance in the study of nonlinear electromagnetic shock waves both in laboratory and astrophysical plasmas.

  13. Study of dynamical behaviour of the plasma in a dc non-transferred plasma torch using fast imaging

    NASA Astrophysics Data System (ADS)

    Goyal, Vidhi; Ravi, G.; Bandyopadhyay, P.; Banerjee, S.; Yugesh, V.; Mukherjee, S.

    2017-03-01

    The dynamical behaviour of the plasma in a dc non-transferred plasma torch is the result of complex interactions between various forces acting on the plasma column. We have studied this behaviour in a novel experiment comprising a low power (˜25 kW) torch and fast imaging diagnostics. The nitrogen gas plasma torch was operated at atmospheric pressure for a wide range of gas flow rates (20-60 lpm) and currents (70-120 A). A strong axial external magnetic field (100-500 G) was introduced and end-on images of the plasma column were captured using a high speed camera of frame rate ˜117 000 fps. The studies have yielded dominant role of external magnetic on the arc root dynamics. The column is clearly distinguishable in three main parts: central plasma, cathode-anode junction, and radial component of column that attaches to the anode. The dynamics of the column, especially the angular rotational speed of the radial part of the column, is analyzed in detail in terms of the forces that act upon it. The nature of the arc root attachment is observed to vary with variation in main experimental parameters, such as current, magnetic field, and flow. Arguments are invoked to explain the observed phenomena and a model of the physical processes is presented to explain the phenomena.

  14. Plasma obestatin is lower at fasting and not suppressed by insulin in insulin-resistant humans.

    PubMed

    Anderwald-Stadler, Marietta; Krebs, Michael; Promintzer, Miriam; Mandl, Martina; Bischof, Martin G; Nowotny, Peter; Kästenbauer, Thomas; Luger, Anton; Prager, Rudolf; Anderwald, Christian

    2007-11-01

    Obestatin, a recently discovered 23-amino acid peptide, is involved in the regulation of appetite and body weight in antagonistic fashion to ghrelin, both deriving from a common precursor peptide. Ghrelin was shown to be associated with insulin resistance, which may also affect obestatin. We investigated the association between insulin resistance and plasma concentrations of obestatin and ghrelin in nondiabetic individuals with high (IS; n = 18, 13 females and 5 males, age 47 +/- 2 yr, BMI = 25.5 +/- 0.9 kg/m(2)) and low (IR; n = 18, 12 females and 6 males, age 45 +/- 2 yr, P = 0.49, BMI = 27.5 +/- 1.1 kg/m(2), P = 0.17) insulin-stimulated glucose disposal (M), measured by 2-h hyperinsulinemic (40 mU.min(-1).m(-2)) isoglycemic clamp tests. M(100-120 min) was higher in IS (10.7 +/- 0.7) than in IR (4.4 +/- 0.2 mg.min(-1).kg(-1), P < 10(-9)), whereas insulin-dependent suppression of free fatty acids (FFA) in plasma was reduced in IR (71 +/- 6% vs. IS: 82 +/- 5%, P < 0.02). In both groups, plasma ghrelin concentrations were comparable at fasting and similarly reduced by 24-28% during insulin infusion. IR had lower fasting plasma obestatin levels (383 +/- 26 pg/ml vs. IS: 469 +/- 23 pg/ml, P < 0.02). Clamp insulin infusion reduced plasma obestatin to approximately 81% of basal values in IS (P < 0.00002), but not in IR. Fasting plasma obestatin was correlated positively with M (r = 0.34, P = 0.04), HDL cholesterol (r = 0.45, P = 0.01), and plasma ghrelin concentrations (r = 0.80, P < 0.000001) and negatively with measures of adiposity, plasma FFA during clamp (r = -0.42, P < 0.01), and systolic blood pressure (r = -0.33, P < 0.05). In conclusion, fasting plasma concentrations of obestatin, but not of ghrelin, are reduced in insulin resistance and are positively associated with whole body insulin sensitivity in nondiabetic humans. Furthermore, plasma obestatin is reduced by insulin in insulin-sensitive but not in insulin-resistant persons.

  15. Role of Combined NNBI and ICRH Heating in FAST H-mode plasmas

    NASA Astrophysics Data System (ADS)

    Cardinali, A.; Calabrò, G.; Di Troia, C.; Marinucci, M.; Baiocchi, B.; Bilato, R.; Brambilla, M.; Briguglio, S.; Fogaccia, G.; Mantica, P.; Vlad, G.; Zonca, F.

    2011-12-01

    The combination of ICRH+NNBI in FAST allows the generation of fast ion populations with different velocity space anisotropy and radial profiles. These energetic ion populations can excite meso-scale fluctuations with the same characteristics of those expected in reactor conditions and, for this reason, FAST can address a number of important burning plasma physics issues. Numerical simulation and modeling of energetic particle physics are based on the use of transport codes that are iteratively coupled with a bi-dimensional full wave-quasi-linear solver for ICRH, in order to determinate the normalized supra-thermal population pressure ßhot. The value of ßhot. as well the energetic particle distribution functions can be used as initial condition for numerical simulation studies, investigating the destabilization and saturation of fast ion driven Alfvénic modes.

  16. Fast and Slow Mode Solitary Waves in a Five Component Plasma

    NASA Astrophysics Data System (ADS)

    Sebastian, Sijo; Michael, Manesh; Varghese, Anu; Sreekala, G.; Venugopal, Chandu

    2016-07-01

    We have investigated fast and slow mode solitary profiles in a five component plasma consisting of positively and negatively charged pair ions, hydrogen ions and hotter and colder electrons. Of these, the heavier ions and colder photo-electrons are of cometary origin while the other components are of solar origin; the electrons being described by kappa distributions. The Zakharov-Kuznetzov (ZK) equation is derived and solutions for fast and slow mode solitary structures are plotted for parameters relevant to that of comet Halley. From the figures, it is seen that the presence of hydrogen ion determines the polarity of fast and slow mode solitary structures. Also different pair ions like He, C and O have significant effect on the width of the fast and slow mode solitary structures.

  17. Charge exchange fast neutral measurement with natural diamond detectors in neon plasma on LHD

    NASA Astrophysics Data System (ADS)

    Saida, T.; Sasao, M.; Isobe, M.; Krasilnikov, A. V.

    2003-03-01

    Charge exchange (CX) fast neutral spectra produced by ion cyclotron resonance frequency hydrogen minority heating in neon and helium majority plasmas sustained by neutral beam injection were measured with perpendicular Natural Diamond Detectors during the fifth campaign in 2002 on large helical devices (LHDs). It was observed that there were differences between fast neutral spectra shapes in neon plasma and those in helium of the same discharge condition with similar plasma parameters. Dominant CX processes in neon and helium plasmas were studied for ionization components from outside of the last closed flux surface. High-energy proton spectra were obtained by taking account of each charge state distribution and responsible charge exchange cross sections. The high-energy proton tail formations in both plasmas were similar for the same heating regime. The relaxation time tendencies of the effective temperatures of a high-energy proton have also shown no differences, indicating that the acceleration and confinement of energetic ions in LHDs are similar in neon and helium plasmas.

  18. Performance of a space-based wavelet compressor for plasma count data on the MMS Fast Plasma Investigation

    NASA Astrophysics Data System (ADS)

    Barrie, A. C.; Smith, S. E.; Dorelli, J. C.; Gershman, D. J.; Yeh, P.; Schiff, C.; Avanov, L. A.

    2017-01-01

    Data compression has been a staple of imaging instruments for years. Recently, plasma measurements have utilized compression with relatively low compression ratios. The Fast Plasma Investigation (FPI) on board the Magnetospheric Multiscale (MMS) mission generates data roughly 100 times faster than previous plasma instruments, requiring a higher compression ratio to fit within the telemetry allocation. This study investigates the performance of a space-based compression standard employing a Discrete Wavelet Transform and a Bit Plane Encoder (DWT/BPE) in compressing FPI plasma count data. Data from the first 6 months of FPI operation are analyzed to explore the error modes evident in the data and how to adapt to them. While approximately half of the Dual Electron Spectrometer (DES) maps had some level of loss, it was found that there is little effect on the plasma moments and that errors present in individual sky maps are typically minor. The majority of Dual Ion Spectrometer burst sky maps compressed in a lossless fashion, with no error introduced during compression. Because of induced compression error, the size limit for DES burst images has been increased for Phase 1B. Additionally, it was found that the floating point compression mode yielded better results when images have significant compression error, leading to floating point mode being used for the fast survey mode of operation for Phase 1B. Despite the suggested tweaks, it was found that wavelet-based compression, and a DWT/BPE algorithm in particular, is highly suitable to data compression for plasma measurement instruments and can be recommended for future missions.

  19. Fasting plasma glucose test at the first prenatal visit as a screen for gestational diabetes.

    PubMed

    Sacks, David A; Chen, Wansu; Wolde-Tsadik, Girma; Buchanan, Thomas A

    2003-06-01

    To determine whether the fasting plasma glucose test administered at the first prenatal visit could serve as an efficient screen for gestational diabetes. A total of 5557 women not known to have diabetes were offered a fasting plasma glucose test at their first prenatal visit. Results less than 100 mg/dL were blinded. A glucose tolerance test was requested immediately of those whose screening test result was 100-125 mg/dL and of all women not identified as having diabetes by their 23rd gestational week. A total of 4507 women (81%) complied with the protocol. Of the 302 women found to have gestational diabetes, 46 (15%) were detected before 24 weeks. A false-positive rate of 57% was found at a threshold fasting glucose concentration giving a sensitivity of 80% for the detection of gestational diabetes. The fasting plasma glucose screening test at the first prenatal visit has good patient compliance. However, its poor specificity (high false-positive rate) makes it an inefficient screening test for gestational diabetes.

  20. STIS MAMA Recovery from Anomalous Shutdown

    NASA Astrophysics Data System (ADS)

    Wheeler, Thomas

    2013-10-01

    This proposal is designed to permit a safe and orderly recovery of the STIS FUV MAMA or NUV MAMA detector after an anomalous shutdown. This is accomplished by using slower-than-normal MCP high-voltage ramp-ups and diagnostics. Anomalous shutdowns can occur because of bright object violations which trigger the Global Hardware Monitor or the Global Software Monitor. Anomalous shutdowns can also occur because of MAMA hardware anomalies or failures. The cause of the shutdown should be thoroughly investigated and understood prior to recovery. Twenty-four hour wait intervals are required after each test for MCP gas desorption and data analysis. Event flags are used to prevent inadvertent MAMA usage.The recovery procedure consists of three separate tests {i.e. visits} to check the MAMA's health after an anomalous shutdown: 1} signal processing electronics check, 2} slow, intermediate voltage high voltage ramp-up, and 3} ramp-up to full operating voltage followed by a fold analysis test {See STIS ISR 98-02R}. Each must be successfully completed before proceeding onto the next. This proposal executes the same steps as Cycle 20 proposal 13150.

  1. ACS SBC Recovery from Anomalous Shutdown

    NASA Astrophysics Data System (ADS)

    Wheeler, Thomas

    2013-10-01

    This proposal is designed to permit a safe and orderly recovery of the SBC {FUV MAMA} detector after an anomalous shutdown. This is accomplished by using slower-than-normal MCP high-voltage ramp-ups and diagnostics. Anomalous shutdowns can occur because of bright object violations, which trigger the Global Hardware Monitor or the Global Software Monitor. Anomalous shutdowns can also occur because of MAMA hardware anomalies or failures. The cause of the shutdown should be thoroughly investigated and understood prior to recovery. Twenty-four hour wait intervals are required after each test for MCP gas desorption and data analysis. Event flag 2 is used to prevent inadvertent MAMA usage. The recovery procedure consists of four separate tests {i.e. visits} to check the MAMA's health after an anomalous shutdown: 1} signal processing electronics check, 2} slow, high-voltage ramp-up to an intermediate voltage, 3} a slow high-voltage ramp-up to the nominal operating HV, and 4} fold analysis test. Each must be completed successfully before proceeding onto the next. During the two high-voltage ramp-ups, dark ACCUM exposures are taken. At high voltage, dark ACCUM exposures and diagnostics are taken. This proposal is based on Proposal 13163 from Cycle 20. For additional MAMA recovery information, see STIS ISR 98-02R.

  2. COS NUV Detector Recovery after Anomalous Shutdown

    NASA Astrophysics Data System (ADS)

    Wheeler, Thomas

    2013-10-01

    This proposal is designed to permit a safe and orderly recovery of the NUV-MAMA detector after an anomalous shutdown. This is accomplished by using slower-than-normal MCP high-voltage ramp-ups and diagnostics. Anomalous shutdowns can occur because of bright object violations which trigger the Global Hardware Monitor or the Global Software Monitor. Anomalous shutdowns can also occur because of MAMA hardware anomalies or failures. The cause of the shutdown should be thoroughly investigated and understood prior to recovery. Twenty-four hour wait intervals are required after each test for MCP gas desorption and data analysis. Event flag 2 is used to prevent inadvertent MAMA usage.The recovery procedure consists of four separate tests {i.e. visits} to check the MAMA's health after an anomalous shutdown: 1} signal processing electronics check, 2} slow, intermediate voltage high-voltage ramp-up, 3} ramp-up to full operating voltage, and 4} fold analysis test {See COS TIR 2010-01}. Each must be successfully completed before proceeding onto the next. This proposal executes the same steps as Cycle 20 proposal 13129. Adjustments were made the the Software Global Monitor {SGM} to account for an increase in the dark counts due to window glow and to align the SGM to previously obtained Fold Analysis event data.

  3. COS NUV Detector Recovery After Anomalous Shutdown

    NASA Astrophysics Data System (ADS)

    Wheeler, Thomas

    2011-10-01

    This proposal is designed to permit a safe and orderly recovery of the NUV-MAMA detector after an anomalous shutdown. This is accomplished by using slower-than-normal MCP high-voltage ramp-ups and diagnostics. Anomalous shutdowns can occur because of bright object violations, which trigger the Global Hardware Monitor or the Global Software Monitor. Anomalous shutdowns can also occur because of MAMA hardware anomalies or failures. The cause of the shutdown should be thoroughly investigated and understood prior to recovery. Twenty-four hour wait intervals are required after each test for MCP gas desorption and data analysis. Event flag 2 is used to prevent inadvertent MAMA usage.The recovery procedure consists of four separate tests {i.e. visits} to check the MAMAâ??s health after an anomalous shutdown: signal processing electronics check, slow, intermediate voltage high-voltage ramp-up, ramp-up to full operating voltage, and fold analysis test {See COS TIR 2010-01}. Each must be successfully completed before proceeding onto the next. This proposal executes the same steps as Cycle 18 proposal 12430.

  4. STIS MAMA Recovery from Anomalous Shutdown

    NASA Astrophysics Data System (ADS)

    Wheeler, Thomas

    2012-10-01

    This proposal is designed to permit a safe and orderly recovery of the STIS FUV MAMA or NUV MAMA detector after an anomalous shutdown. This is accomplished by using slower-than-normal MCP high-voltage ramp-ups and diagnostics. Anomalous shutdowns can occur because of bright object violations, which trigger the Global Hardware Monitor or the Global Software Monitor. Anomalous shutdowns can also occur because of MAMA hardware anomalies or failures. The cause of the shutdown should be thoroughly investigated and understood prior to recovery. Twenty-four hour wait intervals are required after each test for MCP gas desorption and data analysis. Event flags are used to prevent inadvertent MAMA usage.The recovery procedure consists of three separate tests {i.e. visits} to check the MAMAâ_Ts health after an anomalous shutdown: 1} signal processing electronics check, 2} slow, intermediate voltage high voltage ramp-up, and 3} ramp-up to full operating voltage followed by a fold analysis test {See STIS ISR 98-02R}. Each must be successfully completed before proceeding onto the next. This proposal executes the same steps as Cycle 19 proposal 12779.

  5. COS NUV Detector Recovery After Anomalous Shutdown

    NASA Astrophysics Data System (ADS)

    Wheeler, Thomas

    2012-10-01

    This proposal is designed to permit a safe and orderly recovery of the NUV-MAMA detector after an anomalous shutdown. This is accomplished by using slower-than-normal MCP high-voltage ramp-ups and diagnostics. Anomalous shutdowns can occur because of bright object violations, which trigger the Global Hardware Monitor or the Global Software Monitor. Anomalous shutdowns can also occur because of MAMA hardware anomalies or failures. The cause of the shutdown should be thoroughly investigated and understood prior to recovery. Twenty-four hour wait intervals are required after each test for MCP gas desorption and data analysis. Event flag 2 is used to prevent inadvertent MAMA usage.The recovery procedure consists of four separate tests {i.e. visits} to check the MAMAâ_Ts health after an anomalous shutdown: 1} signal processing electronics check, 2} slow, intermediate voltage high-voltage ramp-up, 3} ramp-up to full operating voltage, and 4} fold analysis test {See COS TIR 2010-01}. Each must be successfully completed before proceeding onto the next. This proposal executes almost the same steps as Cycle 19 proposal 12723. Adjustments were made the the Software Global Monitor {SGM} to account for an increase in the dark counts due to window glow and to align the SGM to previously obtained Fold Analysis event data.

  6. Fast camera studies at an electron cyclotron resonance table plasma generator

    SciTech Connect

    Rácz, R.; Biri, S.

    2014-02-15

    A simple table-size ECR plasma generator operates in the ATOMKI without axial magnetic trap and without any particle extraction tool. Radial plasma confinement is ensured by a NdFeB hexapole. The table-top ECR is a simplified version of the 14 GHz ATOMKI-ECRIS. Plasma diagnostics experiments are planned to be performed at this device before installing the measurement setting at the “big” ECRIS. Recently, the plasma generator has been operated in pulsed RF mode in order to investigate the time evolution of the ECR plasma in two different ways. (1) The visible light radiation emitted by the plasma was investigated by the frames of a fast camera images with 1 ms temporal resolution. Since the visible light photographs are in strong correlation with the two-dimensional spatial distribution of the cold electron components of the plasma it can be important to understand better the transient processes just after the breakdown and just after the glow. (2) The time-resolved ion current on a specially shaped electrode was measured simultaneously in order to compare it with the visible light photographs. The response of the plasma was detected by changing some external setting parameters (gas pressure and microwave power) and was described in this paper.

  7. Development and Benchmarking of a Hybrid PIC Code For Dense Plasmas and Fast Ignition

    SciTech Connect

    Witherspoon, F. Douglas; Welch, Dale R.; Thompson, John R.; MacFarlane, Joeseph J.; Phillips, Michael W.; Bruner, Nicki; Mostrom, Chris; Thoma, Carsten; Clark, R. E.; Bogatu, Nick; Kim, Jin-Soo; Galkin, Sergei; Golovkin, Igor E.; Woodruff, P. R.; Wu, Linchun; Messer, Sarah J.

    2014-05-20

    Radiation processes play an important role in the study of both fast ignition and other inertial confinement schemes, such as plasma jet driven magneto-inertial fusion, both in their effect on energy balance, and in generating diagnostic signals. In the latter case, warm and hot dense matter may be produced by the convergence of a plasma shell formed by the merging of an assembly of high Mach number plasma jets. This innovative approach has the potential advantage of creating matter of high energy densities in voluminous amount compared with high power lasers or particle beams. An important application of this technology is as a plasma liner for the flux compression of magnetized plasma to create ultra-high magnetic fields and burning plasmas. HyperV Technologies Corp. has been developing plasma jet accelerator technology in both coaxial and linear railgun geometries to produce plasma jets of sufficient mass, density, and velocity to create such imploding plasma liners. An enabling tool for the development of this technology is the ability to model the plasma dynamics, not only in the accelerators themselves, but also in the resulting magnetized target plasma and within the merging/interacting plasma jets during transport to the target. Welch pioneered numerical modeling of such plasmas (including for fast ignition) using the LSP simulation code. Lsp is an electromagnetic, parallelized, plasma simulation code under development since 1995. It has a number of innovative features making it uniquely suitable for modeling high energy density plasmas including a hybrid fluid model for electrons that allows electrons in dense plasmas to be modeled with a kinetic or fluid treatment as appropriate. In addition to in-house use at Voss Scientific, several groups carrying out research in Fast Ignition (LLNL, SNL, UCSD, AWE (UK), and Imperial College (UK)) also use LSP. A collaborative team consisting of HyperV Technologies Corp., Voss Scientific LLC, FAR-TECH, Inc., Prism

  8. Comparative interactions between fast-flowing magnetized plasmas and comets, Mars, Venus and Titan

    NASA Astrophysics Data System (ADS)

    Mazelle, C.

    This review will summarize recent progress in the space plasma physics of solar system bodies (planets, planetary satellites and comets) interacting with a collisionless plasma wind such as the solar wind. One well-known class of objects are those possessing an intrinsic dynamo field such as the Earth, Mercury or giant planets. Their atmosphere is protected from the incident flow by the external boundary of their magnetosphere where the incident pressure is balanced by the intrinsic magnetic pressure allowing only impulsive penetration of solar wind plasma. For the second class of objects without measurable large scale magnetic field, the electrodynamical coupling occurs directly with the atmosphere and its upper part, the exosphere. This the case of Mars, and Venus and this makes these planets to also share common physical processes with comets. The interaction of Titan with the fast co-rotating plasma inside the magnetosphere of Saturn is another example of such interaction. Their plasma environment consists of characteristic boundaries separating regions with very different plasma conditions and dynamics (collisionless shock, magnetosheath, "induced" magnetosphere, ionosphere,...). Numerous open issues include atmospheric and ionospheric escapes, plasma boundaries and their dynamics, pickup ions, upstream waves, etc. Numerous open issues include atmospheric and ionospheric escapes, plasma boundaries and their dynamics, pickup ions, upstream waves, etc. Recent results in data analysis, e.g., from Mars Global Surveyor and Mars Express at Mars, from Cassini at Saturn and Titan or from Venus Express will be reported and compared with theoretical results, including numerical simulations.

  9. Beams of fast neutral atoms and molecules in low-pressure gas-discharge plasma

    SciTech Connect

    Metel, A. S.

    2012-03-15

    Fast neutral atom and molecule beams have been studied, the beams being produced in a vacuum chamber at nitrogen, argon, or helium pressure of 0.1-10 Pa due to charge-exchange collisions of ions accelerated in the sheath between the glow discharge plasma and a negative grid immersed therein. From a flat grid, two broad beams of molecules with continuous distribution of their energy from zero up to e(U + U{sub c}) (where U is voltage between the grid and the vacuum chamber and U{sub c} is cathode fall of the discharge) are propagating in opposite directions. The beam propagating from the concave surface of a 0.2-m-diameter grid is focused within a 10-mm-diameter spot on the target surface. When a 0.2-m-diameter 0.2-m-high cylindrical grid covered by end disks and composed of parallel 1.5-mm-diameter knitting needles spaced by 4.5 mm is immersed in the plasma, the accelerated ions pass through the gaps between the needles, turn inside the grid into fast atoms or molecules, and escape from the grid through the gaps on its opposite side. The Doppler shift of spectral lines allows for measuring the fast atom energy, which corresponds to the potential difference between the plasma inside the chamber and the plasma produced as a result of charge-exchange collisions inside the cylindrical grid.

  10. FAST TRACK COMMUNICATION: Plasma agents in bio-decontamination by dc discharges in atmospheric air

    NASA Astrophysics Data System (ADS)

    Machala, Zdenko; Chládeková, Lenka; Pelach, Michal

    2010-06-01

    Bio-decontamination of water and surfaces contaminated by bacteria (Salmonella typhimurium) was investigated in two types of positive dc discharges in atmospheric pressure air, in needle-to-plane geometry: the streamer corona and its transition to a novel regime called transient spark with short high current pulses of limited energy. Both generate a cold non-equilibrium plasma. Electro-spraying of treated water through a needle electrode was applied for the first time and resulted in fast bio-decontamination. Experiments providing separation of various biocidal plasma agents, along with the emission spectra and coupled with oxidation stress measurements in the cell membranes helped to better understand the mechanisms of microbial inactivation. The indirect exposure of contaminated surfaces to neutral active species was almost as efficient as the direct exposure to the plasma, whereas applying only UV radiation from the plasma had no biocidal effects. Radicals and reactive oxygen species were identified as dominant biocidal agents.

  11. Advances in High Harmonic Fast Wave Heating of NSTX H-mode Plasmas

    SciTech Connect

    Ryan, Philip Michael; Ahn, Joonwook; Bell, R. E.; Bonoli, P.; Chen, Guangye; Green, David L; Harvey, R. W.; Hosea, J.; Jaeger, Erwin Frederick; Kaye, S.; LeBlanc, B; Maingi, Rajesh; Phillips, Cynthia; Podesta, M.; Taylor, G.; Wilgen, John B; Wilson, J. R.

    2010-01-01

    High-harmonic fast wave (HHFW) heating and current drive is being developed in NSTX to provide bulk electron heating and q(0) control during non-inductively sustained Hmode plasmas fuelled by deuterium neutral-beam injection (NBI). In addition, it is used to assist the plasma current ramp-up. A major modification to increase the RF power limit was made in 2009; the original end-grounded, single end-powered current straps of the 12- element array were replaced with center-grounded, double end-powered straps. Greater than 3 MW have been coupled into NBI-driven, ELMy H-mode plasmas with this upgraded antenna. Improved core HHFW heating, particularly at longer wavelengths and during low-density start-up and plasma current ramp-up, has been obtained by lowering the edge density with lithium wall conditioning, thereby moving the critical density for fast-wave propagation away from the vessel wall [1]. Significant core electron heating of NBI-fuelled H-modes has been observed for the first time over a range of launched wavelengths and H-modes can be accessed by HHFW alone. Visible and IR camera images of the antenna and divertor indicate that fast wave interactions can deposit considerable RF energy on the outboard divertor plate, especially at longer wavelengths that begin to propagate closer to the vessel walls. Edge power loss can also arise from HHFWgenerated parametric decay instabilities; edge ion heating is observed that is wavelength dependent. During plasmas where HHFW is combined with NBI, there is a significant enhancement in neutron rate, and fast-ion D-alpha (FIDA) emission measurements clearly show broadening of the fast-ion profile in the plasma core. Large edge localized modes (ELMs) have been observed immediately following the termination of RF power, whether the power turn off is programmed or due to antenna arcing. Causality has not been established but new experiments are planned and will be reported. Fast digitization of the reflected power signal

  12. Leptin concentrations in plasma and follicular fluid from prepubertal gilts as influenced by fasting, refeeding and insulin.

    PubMed

    Govoni, N; Galeati, G; Castellani, G; Tamanini, C

    2005-03-01

    This study's aim was to examine whether fasting and refeeding would influence leptin levels in both plasma and follicular fluid from prepubertal gilts, and whether insulin affects leptin levels in fasting gilts. In experiment 1, four gilts were fasted for 72 h and then refed. Blood samples were withdrawn during normoalimentation, at the end of fasting, and for 4 h after refeeding. All samples were assayed for leptin; alternate samples were assayed for insulin, glucose and non-esterified fatty acids (NEFA). Fasting caused a decrease in leptin, glucose and insulin levels in plasma, while NEFA concentrations increased. In experiment 2, four gilts were given insulin as a bolus (0.2 IU/kg body weight) after 68 h of fasting. Blood samples were collected every 15 min around insulin administration and were assayed for leptin, insulin and glucose. This experiment shows that insulin administration increases leptin levels during fasting. In experiment 3, gilts were ovariectomized during normal alimentation (n=4), after 48 h of fasting (n=4), and after 48 h of realimentation following 48 h of fasting (n=4). Leptin levels in both plasma and follicular fluid collected after 48 h of fasting were significantly lower than those observed during normoalimentation or refeeding. In conclusion, a transient increase in insulin during fasting is effective in restoring leptin concentrations; in addition, leptin levels in follicular fluid parallel those in plasma.

  13. The influence of feeding and fasting on plasma metabolites in the dogfish shark (Squalus acanthias).

    PubMed

    Wood, Chris M; Walsh, Patrick J; Kajimura, Makiko; McClelland, Grant B; Chew, Shit F

    2010-04-01

    Dogfish sharks are opportunistic predators, eating large meals at irregular intervals. Here we present a synthesis of data from several previous studies on responses in plasma metabolites after natural feeding and during prolonged fasting (up to 56days), together with new data on changes in plasma concentrations of amino acids and non-esterified fatty acids. Post-prandial and long-term fasting responses were compared to control sharks fasted for 7days, a typical inter-meal interval. A feeding frenzy was created in which dogfish were allowed to feed naturally on dead teleosts at two consumed ration levels, 2.6% and 5.5% of body weight. Most responses were more pronounced at the higher ration level. These included increases in urea and TMAO concentrations at 20h, followed by stability through to 56days of fasting. Ammonia levels were low and exhibited little short-term response to feeding, but declined to very low values during the extended fast. Glucose and beta-hydroxybutyrate both fell after feeding, the latter to a greater and more prolonged extent (up to 60h), whereas acetoacetate did not change. During prolonged fasting, glucose concentrations were well regulated, but beta-hydroxybutyrate increased to 2-3-fold control levels. Total plasma amino acid concentrations increased in a biphasic fashion, with peaks at 6-20h, and 48-60h after the meal, followed by homeostasis during the extended fast. Essential and non-essential amino acids generally followed this same pattern, though some exhibited different trends after feeding: taurine, beta-alanine, and glycine (decreases or stability), alanine and glutamine (modest prolonged increases), and threonine, serine, asparagine, and valine (much larger short-term increases). Plasma non-esterified fatty acid concentrations declined markedly through 48h after the 2.6% meal. These data are interpreted in light of companion studies showing elevations in aerobic metabolic rate, urea production, rectal gland function, metabolic

  14. Moringa Oleifera leaf extract increases plasma antioxidant status associated with reduced plasma malondialdehyde concentration without hypoglycemia in fasting healthy volunteers.

    PubMed

    Ngamukote, Sathaporn; Khannongpho, Teerawat; Siriwatanapaiboon, Marent; Sirikwanpong, Sukrit; Dahlan, Winai; Adisakwattana, Sirichai

    2016-12-29

    To investigate the effect of Moringa Oleifera leaf extract (MOLE) on plasma glucose concentration and antioxidant status in healthy volunteers. A randomized crossover design was used in this study. Healthy volunteers were randomly assigned to receive either 200 mL of warm water (10 cases) or 200 mL of MOLE (500 mg dried extract, 10 cases). Blood samples were drawn at 0, 30, 60, 90, and 120 min for measuring fasting plasma glucose (FPG), ferric reducing ability of plasma (FRAP), Trolox equivalent antioxidant capacity (TEAC) and malondialdehyde (MDA). FPG concentration was not signifificantly different between warm water and MOLE. The consumption of MOLE acutely improved both FRAP and TEAC, with increases after 30 min of 30 μmol/L FeSO4 equivalents and 0.18 μmol/L Trolox equivalents, respectively. The change in MDA level from baseline was signifificantly lowered after the ingestion of MOLE at 30, 60, and 90 min. In addition, FRAP level was negatively correlated with plasma MDA level after an intake of MOLE. MOLE increased plasma antioxidant capacity without hypoglycemia in human. The consumption of MOLE may reduce the risk factors associated with chronic degenerative diseases.

  15. Study of fast capillary discharge plasma columns for soft x-ray amplifiers

    NASA Astrophysics Data System (ADS)

    Rocca, Jorge J. G.; Cortazar, O. D.; Szapiro, Benito T.; Tomasel, Fernando G.; Hartshorn, D.

    1994-02-01

    The efficient generation, by a fast discharge, of capillary plasma channels containing Ne-like and Ni-like ions for collisionally excited soft-x-ray lasers is reported. Rapid pulse excitation of capillary channels 1.5 mm in diameter with currents of less than 70 kA produced Ca and Ti plasmas in which atoms are ionized up to the F-like state. Line emission at the wavelengths corresponding to the 3p - 3s and 3d - 3p transitions of Ne-like Ca has been observed.

  16. Monochromatic x-ray sampling streak imager for fast-ignitor plasma observation

    SciTech Connect

    Tanabe, Minoru; Fujiwara, Takashi; Fujioka, Shinsuke; Nishimura, Hiroaki; Shiraga, Hiroyuki; Azechi, Hiroshi; Mima, Kunioki

    2008-10-15

    Ultrafast two-dimensional (2D) x-ray imaging is required to investigate the dynamics of fast-heated core plasma in inertial confinement fusion research. A novel x-ray imager, consisting of two toroidally bent Bragg crystals and an ultrafast 2D x-ray imaging camera, has been demonstrated. Sequential and 2D monochromatic x-ray images of laser-imploded core plasma were obtained with a temporal resolution of 20 ps, a spatial resolution of 31 {mu}m, and a spectral resolution of over 200, simultaneously.

  17. Solitary fast magnetosonic waves propagating obliquely to the magnetic field in cold collisionless plasma

    SciTech Connect

    Kichigin, G. N.

    2016-01-15

    Solutions describing solitary fast magnetosonic (FMS) waves (FMS solitons) in cold magnetized plasma are obtained by numerically solving two-fluid hydrodynamic equations. The parameter domain within which steady-state solitary waves can propagate is determined. It is established that the Mach number for rarefaction FMS solitons is always less than unity. The restriction on the propagation velocity leads to the limitation on the amplitudes of the magnetic field components of rarefaction solitons. It is shown that, as the soliton propagates in plasma, the transverse component of its magnetic field rotates and makes a complete turn around the axis along which the soliton propagates.

  18. Development of fast steering mirror control system for plasma heating and diagnostics

    SciTech Connect

    Okada, K. Kubo, S.; Shimozuma, T.; Yoshimura, Y.; Igami, H.; Takahashi, H.; Tanaka, K.; Kobayashi, S.; Ito, S.; Mizuno, Y.; Ogasawara, S.; Nishiura, M.

    2014-11-15

    A control system for a fast steering mirror has been newly developed for the electron cyclotron heating (ECH) launchers in the large helical device. This system enables two-dimensional scan during a plasma discharge and provides a simple feedback control function. A board mounted with a field programmable gate array chip has been designed to realize feedback control of the ECH beam position to maintain higher electron temperature by ECH. The heating position is determined by a plasma diagnostic signal related to the electron temperature such as electron cyclotron emission and Thomson scattering.

  19. Self-Consistent Modification of a Fast Tail Distribution by Resonant Fields in Nonuniform Plasmas,

    DTIC Science & Technology

    1987-08-01

    to plasmas having a long density scale length L, i.e., (kDL)J’/>> I, where kJ’ is the Debye wave number of the warm background electrons. A threshold...study consists of a one- dimensional, warm fluid background plasma having a zero order density profile no(z), which can be well approximated in the...particle interaction analyzed here is restricted to a fast tail distribution which is initially spatially uniform while the nonuniform warm background

  20. Fast magnetic field annihilation driven by two laser pulses in underdense plasma

    SciTech Connect

    Gu, Y. J.; Kumar, D.; Weber, S.; Korn, G.; Klimo, O.; Bulanov, S. V.; Esirkepov, T. Zh.

    2015-10-15

    Fast magnetic annihilation is investigated by using 2.5-dimensional particle-in-cell simulations of two parallel ultra-short petawatt laser pulses co-propagating in underdense plasma. The magnetic field generated by the laser pulses annihilates in a current sheet formed between the pulses. Magnetic field energy is converted to an inductive longitudinal electric field, which efficiently accelerates the electrons of the current sheet. This new regime of collisionless relativistic magnetic field annihilation with a timescale of tens of femtoseconds can be extended to near-critical and overdense plasma with the ultra-high intensity femtosecond laser pulses.

  1. Shutdown system for a nuclear reactor

    DOEpatents

    Groh, Edward F.; Olson, Arne P.; Wade, David C.; Robinson, Bryan W.

    1984-01-01

    An ultimate shutdown system is provided for termination of neutronic activity in a nuclear reactor. The shutdown system includes bead chains comprising spherical containers suspended on a flexible cable. The containers are comprised of mating hemispherical shells which provide a ruggedized enclosure for reactor poison material. The bead chains, normally suspended above the reactor core on storage spools, are released for downward travel upon command from an external reactor monitor. The chains are capable of horizontal movement, so as to flow around obstructions in the reactor during their downward motion.

  2. Shutdown system for a nuclear reactor

    DOEpatents

    Groh, E.F.; Olson, A.P.; Wade, D.C.; Robinson, B.W.

    1984-06-05

    An ultimate shutdown system is provided for termination of neutronic activity in a nuclear reactor. The shutdown system includes bead chains comprising spherical containers suspended on a flexible cable. The containers are comprised of mating hemispherical shells which provide a ruggedized enclosure for reactor poison material. The bead chains, normally suspended above the reactor core on storage spools, are released for downward travel upon command from an external reactor monitor. The chains are capable of horizontal movement, so as to flow around obstructions in the reactor during their downward motion. 8 figs.

  3. The effect of exercise intensity on plasma and tissue acyl ghrelin concentrations in fasted rats.

    PubMed

    Fathi, Rozita; Ghanbari-Niaki, Abbass; Kraemer, Robert R; Talebi-Garakani, Elahe; Saghebjoo, Marziyeh

    2010-12-10

    This study was conducted to investigate the effect of exercise training and feeding status on plasma and tissue acyl ghrelin concentrations. Thirty-two, eight-week-old male Wistar rats (185±5g) were randomly assigned to one of four groups: high intensity (HI: 34 m/min ~80-85% VO(2)max), moderate intensity (MI: 28 m/min ~70-75% VO(2)max), low intensity (LI: 20 m/min ~50-55% VO(2)max), and sedentary control (SED) groups. All experimental groups performed a 12-week exercise program consisting of treadmill running on a 0° slope for 1 h/day, 5 days/week at their respective training intensity. Twenty four hours following the last training session the animals completed a 12h fast. Rats were then killed, blood was collected and plasma separated; the fundus and soleus muscle were excised and frozen in liquid nitrogen for later analysis. Fasting levels of circulating acyl ghrelin and acyl ghrelin content in the soleus muscle and fundus, as well as glycogen in the soleus muscle were measured. Data were analyzed using one-way ANOVA. Results demonstrated that 12 weeks of exercise training combined with a 12h fast significantly increased plasma as well as soleus muscle concentrations of acyl ghrelin in the HI and MI groups (p<0.05) and reduced acyl ghrelin concentrations in the fundus (p<0.05). The results of the study indicate that chronic treadmill exercise training enhances fasting plasma acyl ghrelin in an intensity-dependent manner which is accompanied by a significant increase in soleus muscle and reduction in fundus acyl ghrelin levels. Copyright © 2010 Elsevier B.V. All rights reserved.

  4. Effects of peanut processing on body weight and fasting plasma lipids.

    PubMed

    McKiernan, Fiona; Lokko, Phoebe; Kuevi, Anna; Sales, Regiane L; Costa, Neuza M B; Bressan, Josefina; Alfenas, Rita C G; Mattes, Richard D

    2010-08-01

    Peanuts and peanut butter are commonly consumed as a snack, meal component and ingredient in various commercial products. Their consumption is associated with reduced CVD risk and they pose little threat to positive energy balance. However, questions have arisen as to whether product form (e.g. whole nut v. butter) and processing properties (e.g. roasting and adding flavours) may compromise their positive health effects. The present study investigated the effects of peanut form and processing on two CVD risk factors: fasting plasma lipids and body weight. One hundred and eighteen adults (forty-seven males and seventy-one females; age 29.2 (sd 8.4) years; BMI 30.0 (sd 4.5) kg/m2) from Brazil, Ghana and the United States were randomised to consume 56 g of raw unsalted (n 23), roasted unsalted (n 24), roasted salted (n 23) or honey roasted (n 24) peanuts, or peanut butter (n 24) daily for 4 weeks. Peanut form and processing did not differentially affect body weight or fasting plasma lipid responses in the total sample. However, HDL-cholesterol increased significantly at the group level, and total cholesterol, LDL-cholesterol and TAG concentrations decreased significantly in individuals classified as having elevated fasting plasma lipids compared with those with normal fasting plasma lipids. These observations suggest that the processing attributes assessed in this trial do not compromise the lipid-lowering effects of peanuts, and do not negatively impact body weight. Further studies are warranted to determine the effects of form and processing on other health risk factors.

  5. Fast Formation of Magnetic Islands in a Plasma in the Presence of Counterstreaming Electrons

    SciTech Connect

    Califano, F.; Attico, N.; Pegoraro, F.; Bertin, G.; Bulanov, S. V.

    2001-06-04

    With the help of 2D-3V (two dimensional in space and three dimensional in velocity) Vlasov simulations we show that the magnetic field generated by the electromagnetic current filamentation instability develops magnetic islands due to the onset of a fast reconnection process that occurs on the electron dynamical time scale. This process is relevant to magnetic channel coalescence in relativistic laser plasma interactions.

  6. Plasma epinephrine predicts fasting glucose in centrally obese African-American women.

    PubMed

    Surwit, Richard S; Williams, Redford B; Lane, James D; Feinglos, Mark N; Kuhn, Cynthia M; Georgiades, Anastasia

    2010-09-01

    The high prevalence of diabetes in African-American (AA) women has been widely assumed to be related to the greater prevalence of obesity in this group. Catecholamine release acting on central adipose tissue has been proposed to be a contributing factor. The aim of this article was to examine the interaction of plasma catecholamines and central adiposity on fasting and nonfasting glucose levels in two separate samples. In both studies, the women were healthy, nondiabetic of similar age. In addition, both studies assessed plasma epinephrine (EPI) and norepinephrine (NOREPI) levels collected at three time points. In study 1, catecholamines were measured during a standardized laboratory mental stress task and in study 2, they were measured during the initial phase (10 min) of an intravenous glucose tolerance test (IVGTT). Results from both studies revealed significant effects of EPI on fasting glucose in the obese women. In study 1, mean EPI levels were significantly related to fasting glucose in AA women with high trunk fat (beta = 0.60, P < 0.001). Because high BMI was associated with high trunk fat in women, we used BMI >30 as a proxy for high trunk fat (>32%) in study 2. In study 2, EPI response to the glucose bolus was a strong predictor of fasting glucose in AA women with BMI >30 (beta = 0.75, P < 0.003). We conclude that the effect of central adiposity on fasting glucose may be moderated by plasma EPI. This suggests that adrenal medullary activity could play a role in the pathophysiology of type 2 diabetes.

  7. The 2013 US Government Shutdown (#Shutdown) and health: an emerging role for social media.

    PubMed

    Merchant, Raina M; Ha, Yoonhee P; Wong, Charlene A; Schwartz, H Andrew; Sap, Maarten; Ungar, Lyle H; Asch, David A

    2014-12-01

    In October 2013, multiple United States (US) federal health departments and agencies posted on Twitter, "We're sorry, but we will not be tweeting or responding to @replies during the shutdown. We'll be back as soon as possible!" These "last tweets" and the millions of responses they generated revealed social media's role as a forum for sharing and discussing information rapidly. Social media are now among the few dominant communication channels used today. We used social media to characterize the public discourse and sentiment about the shutdown. The 2013 shutdown represented an opportunity to explore the role social media might play in events that could affect health.

  8. Existence domains of slow and fast ion-acoustic solitons in two-ion space plasmas

    SciTech Connect

    Maharaj, S. K.; Bharuthram, R.; Singh, S. V. Lakhina, G. S.

    2015-03-15

    A study of large amplitude ion-acoustic solitons is conducted for a model composed of cool and hot ions and cool and hot electrons. Using the Sagdeev pseudo-potential formalism, the scope of earlier studies is extended to consider why upper Mach number limitations arise for slow and fast ion-acoustic solitons. Treating all plasma constituents as adiabatic fluids, slow ion-acoustic solitons are limited in the order of increasing cool ion concentrations by the number densities of the cool, and then the hot ions becoming complex valued, followed by positive and then negative potential double layer regions. Only positive potentials are found for fast ion-acoustic solitons which are limited only by the hot ion number density having to remain real valued. The effect of neglecting as opposed to including inertial effects of the hot electrons is found to induce only minor quantitative changes in the existence regions of slow and fast ion-acoustic solitons.

  9. Stability properties and fast ion confinement of hybrid tokamak plasma configurations

    NASA Astrophysics Data System (ADS)

    Graves, J. P.; Brunetti, D.; Pfefferle, D.; Faustin, J. M. P.; Cooper, W. A.; Kleiner, A.; Lanthaler, S.; Patten, H. W.; Raghunathan, M.

    2015-11-01

    In hybrid scenarios with flat q just above unity, extremely fast growing tearing modes are born from toroidal sidebands of the near resonant ideal internal kink mode. New scalings of the growth rate with the magnetic Reynolds number arise from two fluid effects and sheared toroidal flow. Non-linear saturated 1/1 dominant modes obtained from initial value stability calculation agree with the amplitude of the 1/1 component of a 3D VMEC equilibrium calculation. Viable and realistic equilibrium representation of such internal kink modes allow fast ion studies to be accurately established. Calculations of MAST neutral beam ion distributions using the VENUS-LEVIS code show very good agreement of observed impaired core fast ion confinement when long lived modes occur. The 3D ICRH code SCENIC also enables the establishment of minority RF distributions in hybrid plasmas susceptible to saturated near resonant internal kink modes.

  10. Numerical studies of fast ion slowing down rates in cool magnetized plasma using LSP

    NASA Astrophysics Data System (ADS)

    Evans, Eugene S.; Kolmes, Elijah; Cohen, Samuel A.; Rognlien, Tom; Cohen, Bruce; Meier, Eric; Welch, Dale R.

    2016-10-01

    In MFE devices, rapid transport of fusion products from the core into the scrape-off layer (SOL) could perform the dual roles of energy and ash removal. The first-orbit trajectories of most fusion products from small field-reversed configuration (FRC) devices will traverse the SOL, allowing those particles to deposit their energy in the SOL and be exhausted along the open field lines. Thus, the fast ion slowing-down time should affect the energy balance of an FRC reactor and its neutron emissions. However, the dynamics of fast ion energy loss processes under the conditions expected in the FRC SOL (with ρe <λDe) are analytically complex, and not yet fully understood. We use LSP, a 3D electromagnetic PIC code, to examine the effects of SOL density and background B-field on the slowing-down time of fast ions in a cool plasma. As we use explicit algorithms, these simulations must spatially resolve both ρe and λDe, as well as temporally resolve both Ωe and ωpe, increasing computation time. Scaling studies of the fast ion charge (Z) and background plasma density are in good agreement with unmagnetized slowing down theory. Notably, Z-scaling represents a viable way to dramatically reduce the required CPU time for each simulation. This work was supported, in part, by DOE Contract Number DE-AC02-09CH11466.

  11. Hollow Cathode and Keeper-region Plasma Measurements Using Ultra-fast Miniature Scanning Probes

    NASA Technical Reports Server (NTRS)

    Goebel, Dan M.; Jameson, Kristina K.; Watkins, Ron M.; Katz, Ira

    2004-01-01

    In order to support the development of comprehensive performance and life models for future deep space missions that will utilize ion thrusters, we have undertaken a study of the plasma structure in hollow cathodes using an new pneumatic scanning probe diagnostic. This device is designed to insert a miniature probe directly into the hollow cathode orifice from either the upstream insert region in the interior of the hollow cathode, or from the downstream keeper-plasma region at the exit of the hollow cathode, to provide complete axial profiles of the discharge plasma parameters. Previous attempts to diagnose this region with probes was Limited by the melting of small probes in the intense discharge near the orifice, or caused significant perturbation of the plasma by probes large enough to survive. Our new probe is extremely compact, and when configured as a single Langmuir probe, the ceramic tube insulator is only 0.5mm in diameter and the current collecting conductor has a total area of 0.002 cm2. A series of current-voltage characteristics are obtained by applying a rapid sawtooth voltage waveform to the probe as it is scanned by the pneumatic actuator into and out of the plasma region, The bellow-sealed pneumatic drive scans the probe 4 cm in the cathode insert region and 10 cm in the anode/keeper plasmas region at average speeds of about 1 mm/msec, and the residence time at the end of the insertion stroke in the densest part of the plasma near the orifice is measured to be only 10 msec. Since the voltage sweep time is fast compared to the motion of the probe, axial profiles of the plasma density, temperature and potential with reasonable spatial resolution are obtained. Measurements of the internal cathode pressures and the axial plasma-parameter profiles for a hollow cathode operating at discharge currents of up to 35 A in xenon will be presented.

  12. 33 CFR 127.1205 - Emergency shutdown.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... piping system used to transfer LHG or its vapors to or from a vessel must have a quick-closing shutoff... controlled closing; and, (4) If the piping system is used to transfer a flammable LHG, either have fusible elements that melt at less than 105 °C (221 °F) and activate the emergency shutdown, or have a sensor that...

  13. 33 CFR 127.205 - Emergency shutdown.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) WATERFRONT FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Natural Gas Equipment § 127.205 Emergency shutdown. Each transfer... automatically when the fixed sensors under § 127.201(b) measure LNG concentrations exceeding 40% of the...

  14. 33 CFR 127.1205 - Emergency shutdown.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) WATERFRONT FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Hazardous Gas Equipment § 127.1205 Emergency shutdown. (a) Each... valve to stop the flow of liquid and vapor from the waterfront facility handling LHG if a transfer...

  15. The Relationship of Ion Beams and Fast Flows in the Plasma Sheet Boundary Layer

    NASA Technical Reports Server (NTRS)

    Parks, G. K.; Reme, H.; Lin, R. P.; Sanderson, T.; Germany, G. A.; Spann, James F., Jr.; Brittnacher, M. J.; McCarthy, M.; Chen, L. J.; Larsen, D.; hide

    1998-01-01

    We report new findings on the behavior of plasmas in the vicinity of the plasma sheet boundary layer (PSBL). A large geometrical factor detector on WIND (3D plasma experiment) has discovered a unidirectional ion beam streaming in the tailward direction missed by previous observations. This tailward beam is as intense as the earthward streaming beam and it is found just inside the outer edge of the PSBL where earthward streaming beams are observed. The region where this tailward beam is observed includes an isotropic plasma component which is absent in the outer edge where earthward streaming beams are found. When these different distributions are convolved to calculate the velocity moments, fast flows (greater than 400 km/s) result in the earthward direction and much slower flows (less than 200 km/s) in the tailward direction. These new findings are substantially different from previous observations. Thus, the interpretation of fast flows and earthward and counterstreaming ion beams in terms of a neutral line model must be reexamined.

  16. Fast-discharge excitation of hot capillary plasmas for soft-x-ray amplifiers

    NASA Astrophysics Data System (ADS)

    Rocca, J. J.; Cortázar, O. D.; Szapiro, B.; Floyd, K.; Tomasel, F. G.

    1993-02-01

    High-temperature (Te>150 eV), small-diameter (~200 μm) plasma columns have been efficiently generated by very fast (13 ns rise time, 28 ns full width at half maximum) pulsed discharge excitation of capillary channels filled with preionized gas. Discharges in argon-filled capillaries at currents between 20 and 60 kA produced plasmas with Ar x-AR xiv line emission, in which the degree of ionization was controlled by the magnitude of the current pulse. The characteristics of these plasmas differ from those created by vacuum discharges in the same capillaries and approach those necessary for soft-x-ray amplification in low-Z elements.

  17. Fast gated imaging of the collisionless interaction of a laser-produced and magnetized ambient plasma

    NASA Astrophysics Data System (ADS)

    Heuer, P. V.; Schaeffer, D. B.; Knall, E. N.; Constantin, C. G.; Hofer, L. R.; Vincena, S.; Tripathi, S.; Niemann, C.

    2017-03-01

    The collisionless interaction between a laser-produced carbon plasma (LPP) and an ambient hydrogen plasma in a background magnetic field was studied in a high shot rate experiment which allowed large planar data sets to be collected. Plasma fluorescence was imaged with a fast-gated camera with and without carbon line filters. The resulting images were compared to high-resolution two dimensional (2D) data planes of measured magnetic field and electric potential. Several features in the fluorescence images coincide with features in the field data. Relative intensity was used to determine the initial angular velocity distribution of the LPP and the growth rate of instabilities. These observations may be applied to understand fluorescence images from similar experiments where 2D planes of field data are not available.

  18. EFFECTS OF LASER RADIATION ON MATTER: Fast holographic cinematography of a laser plasma

    NASA Astrophysics Data System (ADS)

    Barikhin, B. A.; Ivanov, A. Yu; Nedolugov, V. I.

    1990-11-01

    A fast holographic cinematography method was used in an investigation of a laser plasma initiated at the surfaces of metal samples by pulses from a rhodamine laser. The time evolution of the electron densities and heavy-particle concentrations was determined and a study was made of the nature of motion of a shock wave front. A weak dependence of the evolution of the shock wave velocity on the target materials (aluminum, copper, zinc) was observed in the average power density range 10-25 MW/cm2. A faster increase in the dimensions of a refracting plasma region, compared with a luminous region, and strong expulsion of cold air by an erosion plasma were recorded.

  19. Interpretation of fast measurements of plasma potential, temperature and density in SOL of ASDEX Upgrade

    NASA Astrophysics Data System (ADS)

    Horacek, J.; Adamek, J.; Müller, H. W.; Seidl, J.; Nielsen, A. H.; Rohde, V.; Mehlmann, F.; Ionita, C.; Havlíčková, E.; ASDEX Upgrade Team

    2010-10-01

    This paper focuses on interpretation of fast (1 µs) and local (2-4 mm) measurements of plasma density, potential and electron temperature in the edge plasma of tokamak ASDEX Upgrade. Steady-state radial profiles demonstrate the credibility of the ball-pen probe. We demonstrate that floating potential fluctuations measured by a Langmuir probe are dominated by plasma electron temperature rather than potential. Spatial and temporal scales are found consistent with expectations based on interchange-driven turbulence. Conditionally averaged signals found for both potential and density are also consistent; however, those for temperature show an unexpected ~4 mm wide decrease by 10% at the very centre of a blob. In the wall shadow, temperature measured by the swept Langmuir probe yields values ~10 eV, whilst the ball-pen temperature gradient is more steep and credible, dropping down to ~1 eV.

  20. Fast functionalization of multi-walled carbon nanotubes by an atmospheric pressure plasma jet.

    PubMed

    Kolacyak, Daniel; Ihde, Jörg; Merten, Christian; Hartwig, Andreas; Lommatzsch, Uwe

    2011-07-01

    The afterglow of an atmospheric pressure plasma has been used for the fast oxidative functionalization of multi-walled carbon nanotubes (MWCNTs). Scanning electron microscopy and Raman spectroscopy demonstrate that the MWCNT morphology is mostly preserved when the MWCNTs are dispersed in a solvent and injected as a spray into the plasma. Contact angle measurements show that this approach enhances the wettability of MWCNTs and reduces their sedimentation in an aqueous dispersion. X-ray photoelectron spectroscopy, IR spectroscopy, and electrokinetic measurements show that oxygen plasma incorporates about 6.6 at.% of oxygen and creates mainly hydroxyl and carboxyl functional groups on the MWCNT surface. The typical effective treatment time is estimated to be in the range of milliseconds. The approach is ideally suited for combination with the industrial gas phase CVD synthesis of MWCNTs.

  1. Higher fasting plasma glucose is associated with striatal and hippocampal shape differences: the 2sweet project.

    PubMed

    Zhang, Tianqi; Shaw, Marnie; Humphries, Jacob; Sachdev, Perminder; Anstey, Kaarin J; Cherbuin, Nicolas

    2016-01-01

    Previous studies have demonstrated associations between higher normal fasting plasma glucose levels (NFG) (<6.1 mmol/L), type 2 diabetes (T2D) and hippocampal atrophy and other cerebral abnormalities. Little is known about the association between plasma glucose and the striatum despite sensorimotor deficits being implicated in T2D. This study aimed to investigate the relationship between plasma glucose levels and striatal and hippocampal morphology using vertex-based shape analysis. A population-based, cross-sectional study. Canberra and Queanbeyan, Australia. 287 cognitively healthy individuals (mean age 63 years, 132 female, 273 Caucasian) with (n=261) or without T2D (n=26), selected from 2551 participants taking part in the Personality & Total Health (PATH) Through Life study by availability of glucose data, MRI scan, and absence of gross brain abnormalities and cognitive impairment. Fasting plasma glucose was measured at first assessment, and MRI images were collected 8 years later. Shape differences indicating outward and inward deformation at the hippocampus and the striatum were examined with FMRIB Software Library-Integrated Registration and Segmentation Toolbox (FSL-FIRST) after controlling for sociodemographic and health variables. Higher plasma glucose was associated with shape differences indicating inward deformation, particularly at the caudate and putamen, among participants with NFG after controlling for age, sex, body mass index (BMI), hypertension, smoking and depressive symptoms. Those with T2D showed shape differences indicating inward deformation at the right hippocampus and bilateral striatum, but outward deformation at the left hippocampus, compared with participants with NFG. These findings further emphasize the importance of early monitoring and management of plasma glucose levels, even within the normal range, as a risk factor for cerebral atrophy.

  2. Elevations of C14:1 and C14:2 Plasma Acylcarnitines in Fasted Children: A Diagnostic Dilemma

    PubMed Central

    Burrage, Lindsay C.; Miller, Marcus J.; Wong, Lee-Jun; Kennedy, Adam D.; Sutton, V. Reid; Sun, Qin; Elsea, Sarah H.; Graham, Brett H.

    2015-01-01

    Objectives To test whether follow-up testing for VLCAD deficiency uncovers a diagnosis in patients with elevations of C14:1 and C14:2 plasma acylcarnitines after a controlled fasting study performed for clinically-suspected hypoglycemia and to compare the acylcarnitine profiles from fasted patients without VLCAD deficiency vs. patients with known VLCAD deficiency to determine if metabolite testing distinguishes these groups. Study design We performed a retrospective chart review and identified 17 patients with elevated C14:1 and C14:2 plasma acylcarnitine levels after a controlled fast and with testing for VLCAD deficiency (ACADVL sequencing or fibroblast fatty acid oxidation studies). The follow-up testing in all patients was inconsistent with a diagnosis of VLCAD deficiency. We compared the plasma acylcarnitine profiles from these fasted patients vs. patients with VLCAD deficiency. Results C14:1/C12:1 was significantly lower (p<0.001) in fasted patients vs. patients with VLCAD deficiency. Metabolomics analysis performed in two fasted patients and one patient with VLCAD deficiency demonstrated evidence for upregulated lipolysis and β-oxidation in the fasted state. Conclusions Elevations of plasma C14:1 and C14:2 acylcarnitines appear to be a physiologic result of lipolysis that occurs with fasting. Both metabolomics analysis and/or C14:1/C12:1 may distinguish C14:1 elevations from physiologic fasting-induced lipolysis vs. VLCAD deficiency. PMID:26602010

  3. COS FUV Recovery after Anomalous Shutdown

    NASA Astrophysics Data System (ADS)

    Wheeler, Thomas

    2012-10-01

    This proposal consists of the steps for turning on and ramping up the COS FUV high voltage in a conservative manner after a HV anomalous shutdown by executing a "reduced set" of visits from Cycle 19 Proposal 12810. The nature of the shutdown, i.e., over-light, HV current transient {"crackle"}, ion feedback {induced by a high energy particle}, or field emission {possibly caused by dust or other particulate on the QE grid or other close-by structure or hardware}, and the value of the commanded HV at the time of the shutdown will determine what visits are executed. Because of gain sag, commanded HV settings updates may be required. First, prior to execution of this proposal or selected visits from this proposal, all preliminary steps should be exercised to gather the necessary diagnostic data, e.g., science data evaluation {if a science exposure was in progress and the science data is available}, memory dumps {DCE, EXEC RAM, and possibly the CS BUFFER}, engineering telemetry, or other information that might provide insight as to the nature of the shutdown and estimated count rate. The complete step-by-step procedure is detailed in the Observing Description, but in summary, the following is done:Day 01 activities, visits 01-07, contain both QE grid off and on HV ramping to HVLow {100/100} with diagnostics {DCE dumps} and darks to exclude QE grid involvement in the shutdown. Subsequent to day 01, all HV ramping will be with the QE grid on with the same diagnostics and exposures. All days end with the setting of COS event flag 3 to prevent any FUV HV commanding.Time is allotted for cognizant detector and COS instrument scientist and engineers to examine data dumps, science exposures, and engineering telemetry. If all is well, the go-ahead will be given to clear flag 3 for the next day's visits.This proposal is modeled after the Cycle 19 Proposal 12718.

  4. Electron Generation and Transport in Intense Relativistic Laser-Plasma Interactions Relevant to Fast Ignition ICF

    SciTech Connect

    Ma, Tammy Yee Wing

    2010-01-01

    The reentrant cone approach to Fast Ignition, an advanced Inertial Confinement Fusion scheme, remains one of the most attractive because of the potential to efficiently collect and guide the laser light into the cone tip and direct energetic electrons into the high density core of the fuel. However, in the presence of a preformed plasma, the laser energy is largely absorbed before it can reach the cone tip. Full scale fast ignition laser systems are envisioned to have prepulses ranging between 100 mJ to 1 J. A few of the imperative issues facing fast ignition, then, are the conversion efficiency with which the laser light is converted to hot electrons, the subsequent transport characteristics of those electrons, and requirements for maximum allowable prepulse this may put on the laser system. This dissertation examines the laser-to-fast electron conversion efficiency scaling with prepulse for cone-guided fast ignition. Work in developing an extreme ultraviolet imager diagnostic for the temperature measurements of electron-heated targets, as well as the validation of the use of a thin wire for simultaneous determination of electron number density and electron temperature will be discussed.

  5. Fast and Slow Mode Solitary Waves in a Five-Component Plasma

    NASA Astrophysics Data System (ADS)

    Sebastian, Sijo; Michael, Manesh; Sreekala, G.; Varghese, Anu; Venugopal, Chandu

    2017-02-01

    We have investigated fast- and slow-mode solitary profiles in a five-component plasma consisting of positively and negatively charged pair ions, hydrogen ions, and hotter and colder electrons. Of these, the heavier ions and colder photoelectrons are of cometary origin while the other components are of solar origin; the electrons are described by kappa distributions. The Zakharov-Kuznetsov (ZK) equation is derived, and solutions for fast- and slow-mode solitary structures are plotted for parameters relevant to comet Halley. We found that the presence of hydrogen ions determines the polarity of the fast- and slow-mode solitary structures. Also, variations of equilibrium number density of hydrogen ions and charge numbers on the heavier pair ions act differently on the fast- and slow-mode solitary structures. The addition of hydrogen ions significantly affects the amplitude of the solitary structures for the fast mode. Further, the cyclotron frequency of the lighter and heavier ions has a noticeable effect on the width of the solitary waves.

  6. Observation and suppression of a new fast ion driven micro burst instability in a field-reversed configuration plasma

    NASA Astrophysics Data System (ADS)

    Deng, B. H.; Korepanov, S.; Belova, E.; Douglass, J.; Beall, M.; Binderbauer, M.; Clary, R.; Detrick, S.; Garate, E.; Gota, H.; Granstedt, E.; Magee, R.; Necas, A.; Putvinski, S.; Roche, T.; Smirnov, A.; Tajima, T.; Thompson, M.; Tuszewski, M.; van Drie, A.; TAE Team

    2016-10-01

    The C-2U experiment offers a unique plasma environment combining a high beta field reversed configuration (FRC) embedded in a low beta magnetic mirror with high power neutral beam injection. The beams are injected tangentially into a modest magnetic field so that the orbits of the resulting fast ions encircle the entire plasma. The dominant population of large orbit fast ions sustains and stabilizes the FRC, suppresses turbulence, and makes a dramatic beneficial impact on the overall plasma performance. Abundant interesting new physics phenomena are observed in this high performance FRC operation regime, including micro bursts, which are benign, periodic bursting small amplitude down chirping fluctuations seen by several diagnostics. Detailed analysis of the micro bursts measurement data, bulk plasma equilibrium profiles, and fast ion orbit characteristics show that the micro bursts might be driven by a small number of resonant fast ions, and can be suppressed when the number of resonant particles is reduced.

  7. Effects of fasting on plasma glucose and prolonged tracer measurement of hepatic glucose output in NIDDM

    SciTech Connect

    Glauber, H.; Wallace, P.; Brechtel, G.

    1987-10-01

    We studied the measurement of hepatic glucose output (HGO) with prolonged (3-/sup 3/H)glucose infusion in 14 patients with non-insulin-dependent diabetes mellitus (NIDDM). Over the course of 10.5 h, plasma glucose concentration fell with fasting by one-third, from 234 +/- 21 to 152 +/- 12 mg/dl, and HGO fell from 2.35 +/- 0.18 to 1.36 +/- 0.07 mg . kg-1 . min-1 (P less than .001). In the basal state, HGO and glucose were significantly correlated (r = 0.68, P = .03), and in individual patients, HGO and glucose were closely correlated as both fell with fasting (mean r = 0.79, P less than .01). Plasma (3-/sup 3/H)glucose radioactivity approached a steady state only 5-6 h after initiation of the primed continuous infusion, and a 20% overestimate of HGO was demonstrated by not allowing sufficient time for tracer labeling of the glucose pool. Assumption of steady-state instead of non-steady-state kinetics in using Steele's equations to calculate glucose turnover resulted in a 9-24% overestimate of HGO. Stimulation of glycogenolysis by glucagon injection demonstrated no incorporation of (3-/sup 3/H)glucose in hepatic glycogen during the prolonged tracer infusion. In a separate study, plasma glucose was maintained at fasting levels (207 +/- 17 mg/dl) for 8 h with the glucose-clamp technique. Total glucose turnover rates remained constant during this prolonged tracer infusion. However, HGO fell to 30% of the basal value simply by maintaining fasting hyperglycemia in the presence of basal insulin levels.

  8. Fasting plasma total ghrelin concentrations in monozygotic twins discordant for obesity.

    PubMed

    Leskelä, Piia; Ukkola, Olavi; Vartiainen, Johanna; Rönnemaa, Tapani; Kaprio, Jaakko; Bouchard, Claude; Kesäniemi, Y Antero

    2009-02-01

    Ghrelin is a hormone that is involved in the regulation of food intake. Neuronal, endocrine, and genetic factors have been shown to regulate plasma ghrelin levels; but the determinants of fasting ghrelin concentrations are not yet fully understood. The main aim was to explore the roles of adiposity and genetic differences in determining fasting plasma total ghrelin levels. We measured total ghrelin levels in a population of 23 monozygotic twin pairs discordant for obesity. In addition, 2 variants of ghrelin gene, namely, Arg51Gln and Leu72Met, were genotyped in 3 populations of monozygotic twin pairs: 23 obesity-discordant, 43 lean-concordant, and 46 obesity-concordant twin pairs. In discordant twins, lean co-twins had higher fasting plasma total ghrelin levels (950 pg/mL, SD = 328 pg/mL) than obese twins (720 pg/mL, SD = 143 pg/mL; P = .003). Arg51Gln-polymorphism of the ghrelin gene was equally distributed between the twin groups. However, there were significant differences in genotype frequencies at the Leu72Met polymorphism between the discordant and obese-concordant groups (P = .003) and between the discordant and lean-concordant groups (P = .011), but not between the 2 concordant groups. In the discordant group, there were fewer Met carriers (4%) than among the obese (17%) or the lean-concordant groups (15%). Plasma total ghrelin levels are affected by acquired obesity independent of genetic background. The Leu72 allele is particularly common among monozygotic twins discordant for obesity, suggesting that this ghrelin allele is more permissive in the regulation of energy balance. The ghrelin gene may thus play a role in the regulation of variability of body weight, such that Leu72 allele carriers are more prone to weight variability in response to environmental factors.

  9. Fast Sausage Modes in Magnetic Tubes with Continuous Transverse Profiles: Effects of a Finite Plasma Beta

    NASA Astrophysics Data System (ADS)

    Chen, Shao-Xia; Li, Bo; Xiong, Ming; Yu, Hui; Guo, Ming-Zhe

    2016-12-01

    While standing fast sausage modes in flare loops are often invoked to interpret quasi-periodic pulsations (QPPs) in solar flares, it is unclear as to how they are influenced by the combined effects of a continuous transverse structuring and a finite internal plasma beta ({β }{{i}}). We derive a generic dispersion relation governing linear sausage waves in straight magnetic tubes for which plasma pressure is not negligible, and the density and temperature inhomogeneities of essentially arbitrary form take place in a layer of arbitrary width. Focusing on fast modes, we find that {β }{{i}} only weakly influences {k}{{c}}, the critical longitudinal wavenumber separating the leaky from trapped modes. Likewise, for both trapped and leaky modes, the periods P in units of the transverse fast time depend only weakly on {β }{{i}}, which is compatible with the fact that the effective wave vectors of fast sausage modes are largely perpendicular to the background magnetic field. However, a weak {β }{{i}} dependence of the damping times τ is seen only when the length-to-radius ratio L/R is ∼50% larger than some critical value π /({k}{{c}}R), which itself rather sensitively depends on the density contrast, profile steepness, as well as on how the transverse structuring is described. In the context of QPPs, we conclude that the much simpler zero-beta theory can be employed for trapped modes, as long as one sees the deduced internal Alfvén speed as actually being the fast speed. In contrast, effects due to a finite beta in flare loops should be considered when leaky modes are exploited.

  10. EFFECTS OF LASER RADIATION ON MATTER. LASER PLASMA: Conversion of the energy of fast electrons to thermal plasma radiation

    NASA Astrophysics Data System (ADS)

    Vergunova, G. A.; Rozanov, Vladislav B.

    1992-01-01

    An analysis is made of the conversion of the energy of highly energetic fast electrons, generated by the action of CO2 laser radiation on a target, into characteristic radiation emitted by a plasma formed from shell targets which, for instance, may be present inside targets irradiated by the CO2 laser. Analytical formulas are obtained for the temperature of the converted radiation. The results show that it is possible to control this radiation by choosing the parameters of the target and of the fast electron flux. The efficiency of conversion into characteristic thermal radiation is found numerically to be 95%. This method of conversion is more favorable than direct interaction of CO2 laser radiation with a target since the emitting region is localized in the target mass. When a laser interacts with a target the mass of this region increases with time and so the temperature of the emitted radiation is lower than in the case when fast electrons act on the target.

  11. 40 CFR 1037.660 - Automatic engine shutdown systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 34 2013-07-01 2013-07-01 false Automatic engine shutdown systems... § 1037.660 Automatic engine shutdown systems. This section specifies requirements that apply for certified automatic engine shutdown systems (AES) that are modeled under § 1037.520. It does not apply for...

  12. 40 CFR 1037.660 - Automatic engine shutdown systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Automatic engine shutdown systems... § 1037.660 Automatic engine shutdown systems. This section specifies requirements that apply for certified automatic engine shutdown systems (AES) that are modeled under § 1037.520. It does not apply for...

  13. 40 CFR 63.1272 - Startups, shutdowns, and malfunctions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 11 2011-07-01 2011-07-01 false Startups, shutdowns, and malfunctions... Facilities § 63.1272 Startups, shutdowns, and malfunctions. (a) The provisions set forth in this subpart shall apply at all times except during startups or shutdowns, during malfunctions, and during periods...

  14. 40 CFR 63.1272 - Startups, shutdowns, and malfunctions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Startups, shutdowns, and malfunctions... Facilities § 63.1272 Startups, shutdowns, and malfunctions. (a) The provisions set forth in this subpart shall apply at all times except during startups or shutdowns, during malfunctions, and during periods...

  15. 40 CFR 63.762 - Startups, shutdowns, and malfunctions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 10 2011-07-01 2011-07-01 false Startups, shutdowns, and malfunctions... Facilities § 63.762 Startups, shutdowns, and malfunctions. (a) The provisions set forth in this subpart shall apply at all times except during startups or shutdowns, during malfunctions, and during periods of...

  16. 40 CFR 63.762 - Startups, shutdowns, and malfunctions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Startups, shutdowns, and malfunctions... Facilities § 63.762 Startups, shutdowns, and malfunctions. (a) The provisions set forth in this subpart shall apply at all times except during startups or shutdowns, during malfunctions, and during periods of...

  17. Spectroscopic investigation of fast (ns) magnetic field penetration in a plasma

    NASA Astrophysics Data System (ADS)

    Sarfaty, M.; Shpitalnik, R.; Arad, R.; Weingarten, A.; Krasik, Ya. E.; Fruchtman, A.; Maron, Y.

    1995-06-01

    The time-dependent magnetic field spatial distribution in a coaxial positive-polarity plasma opening switch (POS) carrying a current ≂135 kA during ≂100 ns, was investigated by two methods. In the first, ionic line emission was observed simultaneously for two polarizations to yield the Doppler and Zeeman contributions to the line profiles. In the second method, the axial velocity distribution of ions was determined, giving the magnetic field through the ion equation of motion. This method requires knowledge of the electron density, here obtained from the observed particle ionization times. To this end, a lower bound for the electron kinetic energy was determined using various line intensities and time-dependent collisional-radiative calculations. An important necessity for POS studies is the locality of all measurements in r, z, and θ. This was achieved by using laser evaporation to seed the plasma nonperturbingly with the species desired for the various measurements. The Zeeman splitting and the ion motion showed magnetic field penetration through the 3.5 cm long plasma at a velocity ≂108 cm/s. The current density was found to be relatively high at the load-side edge of the switch plasma. It is suggested that this may cause plasma acceleration into the vacuum section toward the load, which is supported by charge-collector measurements. The fast magnetic field penetration agrees with estimates based on the Hall-field mechanism.

  18. Magnetic field measurements for study of fast electron transport in magnetized HED plasma

    NASA Astrophysics Data System (ADS)

    Sawada, Hiroshi; Griffin, Brandon; Presura, Radu; Haque, Showera; Sentoku, Yasuhiko

    2014-10-01

    Interaction of megagauss magnetic fields with high energy density (HED) plasma is of great interest in the field of magnetized plasma. The field changes fundamental properties of the HED plasma such as thermal and magnetic diffusion. A coupled capability utilizing the 1.0 MA Zebra pulsed power generator and the 50 TW Leopard laser at Nevada Terawatt Facility enables to create such a condition for studies of magnetized plasma properties. We have conducted an experiment to measure magnetic fields generated by a 1.0 MA, 100 ns Zebra pulsed current in stainless steel coils. Using a 532 nm continuous laser from a single longitudinal mode laser system, the temporal change in the magnetic field was measured with the Faraday rotation in F2 glass. The probe laser passing through the 1.5 mm in radius and 1.75 mm thick glass placed in the vicinity of the inductive coils was split with a Glan-Taylor prism to measure vertical and horizontal polarization components with photodiodes. We will present the analysis of the experimental result and a design of a coupled experiment for study of fast electron transport in the magnetized plasma.

  19. Nonlinear interaction of fast particles with Alfven waves in toroidal plasmas

    SciTech Connect

    Candy, J.; Borba, D.; Huysmans, G.T.A.; Kerner, W.; Berk, H.L.

    1996-12-17

    A numerical algorithm to study the nonlinear, resonant interaction of fast particles with Alfven waves in tokamak geometry has been developed. The scope of the formalism is wide enough to describe the nonlinear evolution of fishbone modes, toroidicity-induced Alfven eigenmodes and ellipticity-induced Alfven eigenmodes, driven by both passing and trapped fast ions. When the instability is sufficiently weak, it is known that the wave-particle trapping nonlinearity will lead to mode saturation before wave-wave nonlinearities are appreciable. The spectrum of linear modes can thus be calculated using a magnetohydrodynamic normal-mode code, then nonlinearly evolved in time in an efficient way according to a two-time-scale Lagrangian dynamical wave model. The fast particle kinetic equation, including the effect of orbit nonlinearity arising from the mode perturbation, is simultaneously solved of the deviation, {delta}f = f {minus} f{sub 0}, from an initial analytic distribution f{sub 0}. High statistical resolution allows linear growth rates, frequency shifts, resonance broadening effects, and nonlinear saturation to be calculated quickly and precisely. The results have been applied to an ITER instability scenario. Results show that weakly-damped core-localized modes alone cause negligible alpha transport in ITER-like plasmas--even with growth rates one order of magnitude higher than expected values. However, the possibility of significant transport in reactor-type plasmas due to weakly unstable global modes remains an open question.

  20. Neutron Production and Fast Deuteron Characteristics at the Plasma Focus Discharge

    SciTech Connect

    Kubes, P.; Kravarik, J.; Klir, D.; Rezac, K.; Scholz, M.; Paduch, M.; Ivanova-Stanik, I.; Karpinski, L.; Tomaszewski, K.

    2009-01-21

    This paper summarized the results of interferometry, X-ray and neutron diagnostics performed at the plasma focus facility filled with deuterium. The fusion processes are produced mainly in the dense and hot spherical structure of 2 cm diameter 5-8 cm in front of the anode. The electron temperature of this structure is about 750 eV and the density 5x10{sup 24}-5x10{sup 25}. The neutron energy distribution was calculated using time of flight analysis and showed the dominant direction of the fast deuteron velocity downstream. The deuteron energy distribution was estimated supposing isotropy distribution of the sum of opposite orientation. The total number of fast deuterons in the energy range of 10-400 keV is about 10{sup 18} with total energy of 20 kJ. Plasma in the spherical structure is heated dominantly with ion-ion Coulomb collisions of fast deuterons in the energy range below 10 keV.

  1. High Voltage, Fast-Switching Module for Active Control of Magnetic Fields and Edge Plasma Currents

    NASA Astrophysics Data System (ADS)

    Ziemba, Timothy; Miller, Kenneth; Prager, James; Slobodov, Ilia

    2016-10-01

    Fast, reliable, real-time control of plasma is critical to the success of magnetic fusion science. High voltage and current supplies are needed to mitigate instabilities in all experiments as well as disruption events in large scale tokamaks for steady-state operation. Silicon carbide (SiC) MOSFETs offer many advantages over IGBTs including lower drive energy requirements, lower conduction and switching losses, and higher switching frequency capabilities; however, these devices are limited to 1.2-1.7 kV devices. As fusion enters the long-pulse and burning plasma eras, efficiency of power switching will be important. Eagle Harbor Technologies (EHT), Inc. developing a high voltage SiC MOSFET module that operates at 10 kV. This switch module utilizes EHT gate drive technology, which has demonstrated the ability to increase SiC MOSFET switching efficiency. The module will allow more rapid development of high voltage switching power supplies at lower cost necessary for the next generation of fast plasma feedback and control. EHT is partnering with the High Beta Tokamak group at Columbia to develop detailed high voltage module specifications, to ensure that the final product meets the needs of the fusion science community.

  2. Spectral Emission of fast non-Maxwellian Atoms at metallic Surfaces in low density Plasmas

    NASA Astrophysics Data System (ADS)

    Dickheuer, Sven; Marchuk, Oleksandr; Brandt, Christian; Pospieszczyk, Albrecht

    2016-09-01

    We have observed Doppler shifted components of the Balmer-lines emitted by fast non-Maxwellian atoms using different targets in a linear magnetized plasma in the PSI-2 device. In a pure hydrogen plasma the Doppler shifted components of the Balmer emission lines cannot be detected above the signal-to-noise-ratio. However, in a mixed H/Ar plasma with composition of 1:1 the Doppler red- and blue-shifted components can be clearly observed. The Balmer-lines are analyzed by optical emission spectroscopy at observations angles of 35° and 90°. For target materials we use Ag, Pd, Fe and C. An acceleration potential can be applied to the target to change the kinetic energy of the incoming ions between 40 and 200 eV enabling the observation of the Doppler shifted components. The emission mechanism is discussed in details and is probably due to excitation transfer from metastable argon atoms to the fast hydrogen atoms. The Doppler shifted signal can be used to determine the properties of the surfaces, e.g., the energy and angular distribution of reflected atoms. Also the spectral reflectance of the target surface can be obtained and tested against the reference data and measurements with light calibration sources.

  3. Ion pinhole imaging diagnostics on fast ion source in femtosecond laser plasma of cluster targets.

    PubMed

    Makarov, Sergey; Pikuz, Sergey; Faenov, Anatoly; Pikuz, Tatiana; Fukuda, Yuji; Skobelev, Igor; Zhvaniya, Irina; Varzar, Sergey; Kando, Masaki; Kodama, Ryousuke

    2017-07-10

    The spatial configuration of the ion source generated under femtosecond laser interaction with clusters is investigated. While intense laser pulses (36 fs, 60 mJ, intensity of 4 × 10(17) W/cm(2)) propagated in CO2 cluster (~0.22 μm in diameter) media, the shape of the obtained plasma ion source was registered for the first time by means of pinhole imaging method. The remarkable decrease in fast ion yield in the vicinity of the assumed best laser focus near the gas cluster jet axis is observed. Such observed anisotropy of the ion source is suggested to originate from the influence of the laser prepulse destroying clusters in advance to the arrival of the main pulse. The assumption is confirmed by optical shadowgraphy images of the plasma channel and is important for further development of an efficient laser-plasma-based fast ion source. Following the observed geometry of the ion source, the laser intensity limit allowing to accelerate ions to ~100 keV energy range was estimated.

  4. Dietary Sulfur Amino Acid Effects on Fasting Plasma Cysteine/Cystine Redox Potential in Humans

    PubMed Central

    Jones, Dean P.; Park, Youngja; Gletsu-Miller, Nana; Liang, Yongliang; Yu, Tianwei; Accardi, Carolyn Jonas; Ziegler, Thomas R.

    2010-01-01

    Objective Oxidation of plasma cysteine/cystine (Cys/CySS) redox potential (EhCySS) has been associated with risk factors for cardiovascular disease in humans. Cys and CySS are derived from dietary sulfur amino acids (SAA), but the specific effects of SAA depletion and repletion on Cys/CySS redox indices are unknown. The present study examined the effect of dietary SAA intake level on free Cys, free CySS and EhCySS in human plasma under fasting conditions. Research Methods and Procedures Healthy individuals aged 18–36 y (n=13) were equilibrated to foods providing the RDA for SAA and then fed chemically defined diets without SAA (0 mg·kg−1·d−1; n=13) followed by SAA at levels approximating the mean (56 mg·kg−1·d−1; n=8) or 99th percentile (117 mg·kg−1·d−1; n=5) intake levels of Americans. Fasting plasma samples were collected daily during 4-d study periods and analyzed for free Cys, free CySS and the EhCySS. Results The SAA-free diet significantly (p<0.05) decreased plasma free Cys concentrations and oxidized EhCySS values after 4 days of SAA depletion. With SAA repletion at 56 mg·kg−1·d− 1, plasma free Cys increased significantly and values for EhCySS became more reducing. Administration of a diet providing a higher dose of SAA (117 mg·kg−1·d−1) resulted in a significantly higher level of free Cys and a more reducing EhCySS. Conclusions These results show that free Cys and Cys/CySS redox potential (EhCySS) in fasting plasma are affected by dietary SAA intake level in humans. Significant changes occur slowly over 4 days with insufficient SAA intake, but rapidly (after 1 day) with repletion. PMID:20471805

  5. Increased fasting plasma acylation-stimulating protein concentrations in nephrotic syndrome.

    PubMed

    Ozata, Metin; Oktenli, Cagatay; Gulec, Mustafa; Ozgurtas, Taner; Bulucu, Fatih; Caglar, Kayser; Bingol, Necati; Vural, Abdulgaffar; Ozdemir, I Caglayan

    2002-02-01

    Acylation-stimulating protein (ASP) is an adipocyte-derived protein that has recently been suggested to play an important role in the regulation of lipoprotein metabolism and triglyceride (TG) storage. ASP also appears to have a role in the regulation of energy balance. In addition to its role as a hormonal regulator of body weight and energy expenditure, leptin is now implicated as a regulatory molecule in lipid metabolism. However, little is known about the alterations in fasting plasma ASP and leptin concentrations in the nephrotic syndrome. As hyperlipidemia is one of the most striking manifestations of the nephrotic syndrome, we have investigated fasting plasma ASP and leptin levels and their relation to lipid levels in this syndrome. Twenty-five patients with untreated nephrotic syndrome and 25 age-, sex-, and body mass index-matched healthy controls were included in the study. Fasting plasma lipoproteins, TG, total cholesterol, lipoprotein(a), apolipoprotein AI (apoAI), apoB, urinary protein, plasma albumin, third component of complement (C3), ASP, and leptin levels were measured in both groups. Total cholesterol, TG, low and very low density lipoproteins, lipoprotein(a), apoB, and urinary protein levels were increased in the patient group, whereas plasma albumin, high density lipoprotein cholesterol, and apoAI levels were decreased compared with those in the control group (P < 0.001). Plasma ASP levels were significantly higher in the patient group compared with the control subjects (133.72 +/- 65.14 vs. 29.93 +/- 12.68 nmol/liter; P < 0.001), whereas leptin (2.69 +/- 2.06 vs. 3.99 +/- 2.99 ng/ml; P = 0.118) and C3 (1.01 +/- 0.25 vs. 1.06 +/- 0.23 g/liter; P = 0.662) levels were not significantly different between the two groups. Plasma leptin levels were correlated with body mass index in both nephrotic patients (r(s) = 0.86; P < 0.001) and controls (r(s) = 0.98; P < 0.001), but were not correlated with the other parameters. Fasting ASP concentrations

  6. CHARACTERISTICS OF A FAST RISE TIME POWER SUPPLY FOR A PULSED PLASMA REACTOR FOR CHEMICAL VAPOR DESTRUCTION

    EPA Science Inventory

    Rotating spark gap devices for switching high-voltage direct current (dc) into a corona plasma reactor can achieve pulse rise times in the range of tens of nanoseconds. The fast rise times lead to vigorous plasma generation without sparking at instantaneous applied voltages highe...

  7. CHARACTERISTICS OF A FAST RISE TIME POWER SUPPLY FOR A PULSED PLASMA REACTOR FOR CHEMICAL VAPOR DESTRUCTION

    EPA Science Inventory

    Rotating spark gap devices for switching high-voltage direct current (dc) into a corona plasma reactor can achieve pulse rise times in the range of tens of nanoseconds. The fast rise times lead to vigorous plasma generation without sparking at instantaneous applied voltages highe...

  8. Effects of prolonged fasting on plasma cortisol and TH in postweaned northern elephant seal pups

    NASA Technical Reports Server (NTRS)

    Ortiz, R. M.; Wade, C. E.; Ortiz, C. L.

    2001-01-01

    Northern elephant seal (Mirounga angustirostris) pups rely on the oxidation of fat stores as their primary source of energy during their 8- to 12-wk postweaning fast; however, potential endocrine mechanisms involved with this increased fat metabolism have yet to be examined. Therefore, 15 pups were serially blood sampled in the field during the first 7 wk of their postweaning fast to examine the changes in plasma concentrations of cortisol and thyroid hormones (TH), which are involved in fat metabolism in other mammals. Cortisol increased, indicating that it contributed to an increase in lipolysis. Increased total triiodothyronine (tT(3)) and thyroxine (tT(4)) may not reflect increased thyroid gland activity, but rather alterations in hormone metabolism. tT(3)-to-tT(4) ratio decreased, suggesting a decrease in thyroxine (T(4)) deiodination, whereas the negative correlation between total proteins and free T(4) suggests that the increase in free hormone is attributed to a decrease in binding globulins. Changes in TH are most similar to those observed during hibernation than starvation in mammals, suggesting that the metabolic adaptations to natural fasting are more similar to hibernation despite the fact these animals remain active throughout the fasting period.

  9. Effects of prolonged fasting on plasma cortisol and TH in postweaned northern elephant seal pups

    NASA Technical Reports Server (NTRS)

    Ortiz, R. M.; Wade, C. E.; Ortiz, C. L.

    2001-01-01

    Northern elephant seal (Mirounga angustirostris) pups rely on the oxidation of fat stores as their primary source of energy during their 8- to 12-wk postweaning fast; however, potential endocrine mechanisms involved with this increased fat metabolism have yet to be examined. Therefore, 15 pups were serially blood sampled in the field during the first 7 wk of their postweaning fast to examine the changes in plasma concentrations of cortisol and thyroid hormones (TH), which are involved in fat metabolism in other mammals. Cortisol increased, indicating that it contributed to an increase in lipolysis. Increased total triiodothyronine (tT(3)) and thyroxine (tT(4)) may not reflect increased thyroid gland activity, but rather alterations in hormone metabolism. tT(3)-to-tT(4) ratio decreased, suggesting a decrease in thyroxine (T(4)) deiodination, whereas the negative correlation between total proteins and free T(4) suggests that the increase in free hormone is attributed to a decrease in binding globulins. Changes in TH are most similar to those observed during hibernation than starvation in mammals, suggesting that the metabolic adaptations to natural fasting are more similar to hibernation despite the fact these animals remain active throughout the fasting period.

  10. Fast steel-cleanness characterization by means of laser-assisted plasma spectrometric methods.

    PubMed

    Müller, Gregor; Stahnke, Frank; Bleiner, Davide

    2006-12-15

    Laser-assisted plasma spectrometry is a palette of analytical techniques (L-OES, LA-ICP-MS) capable of fast spatially-resolved elemental analysis in the micrometer range. For fast estimation of the occurrence in steel samples of non-metallic inclusions, which degrade the material's technical properties, simultaneous OES detection and sequential ICP-MS detection were compared. Histograms were obtained for the intensity distribution of the acquired signals (laser pulse statistics). The skewness coefficient of the histograms for Al (indicator of non-metallic inclusions) was found to be clearly dependent on the fraction of non-metallic inclusions in the case of scanning L-OES. For LA-ICP-MS less clear dependence was observed, which was influenced by the acquisition characteristics. In fact, less measurement throughput limited for LA-ICP-MS the counting statistics to an extent that overrides the benefit of higher detection power as compared to L-OES.

  11. The sound generated by a fast parton in the quark-gluon plasma is a crescendo

    NASA Astrophysics Data System (ADS)

    Neufeld, R. B.; Müller, B.

    2009-11-01

    The total energy deposited into the medium per unit length by a fast parton traversing a quarkgluon plasma is calculated. We take the medium excitation due to collisions to be given by the well known expression for the collisional drag force. The parton's radiative energy loss contributes to the energy deposition because each radiated gluon acts as an additional source of collisional energy loss in the medium. In our model, this leads to a length dependence on the differential energy loss due to the interactions of radiated gluons with the medium. The final result, which is a sum of the primary and the secondary contributions, is then treated as the coefficient of a local hydrodynamic source term. Results are presented for energy density wave induced by two fast, back-to-back partons created in an initial hard interaction.

  12. Fast, Deep-Record-Length, Fiber-Coupled Photodiode Imaging Array for Plasma Diagnostics

    NASA Astrophysics Data System (ADS)

    Brockington, Samuel; Case, Andrew; Witherspoon, F. Douglas

    2014-10-01

    HyperV Technologies has been developing an imaging diagnostic comprised of an array of fast, low-cost, long-record-length, fiber-optically-coupled photodiode channels to investigate plasma dynamics and other fast, bright events. By coupling an imaging fiber bundle to a bank of amplified photodiode channels, imagers and streak imagers of 100 to 1000 pixels can be constructed. By interfacing analog photodiode systems directly to commercial analog-to-digital converters and modern memory chips, a prototype 100 pixel array with an extremely deep record length (128 k points at 20 Msamples/s) and 10 bit pixel resolution has already been achieved. HyperV now seeks to extend these techniques to construct a prototype 1000 Pixel framing camera with up to 100 Msamples/sec rate and 10 to 12 bit depth. Preliminary experimental results as well as Phase 2 plans will be discussed. Work supported by USDOE Phase 2 SBIR Grant DE-SC0009492.

  13. Fast, Deep-Record-Length, Fiber-Coupled Photodiode Imaging Array for Plasma Diagnostics

    NASA Astrophysics Data System (ADS)

    Brockington, Samuel; Case, Andrew; Witherspoon, F. Douglas

    2015-11-01

    HyperV Technologies has been developing an imaging diagnostic comprised of an array of fast, low-cost, long-record-length, fiber-optically-coupled photodiode channels to investigate plasma dynamics and other fast, bright events. By coupling an imaging fiber bundle to a bank of amplified photodiode channels, imagers and streak imagers can be constructed. By interfacing analog photodiode systems directly to commercial analog-to-digital converters and modern memory chips, a scalable solution for 100 to 1000 pixel systems with 14 bit resolution and record-lengths of 128k frames has been developed. HyperV is applying these techniques to construct a prototype 1000 Pixel framing camera with up to 100 Msamples/sec rate and 10 to 14 bit depth. Preliminary experimental results as well as future plans will be discussed. Work supported by USDOE Phase 2 SBIR Grant DE-SC0009492.

  14. Associations among objectively measured physical activity, fasting plasma homocysteine concentration, and MTHFR C677T genotype.

    PubMed

    Murakami, Haruka; Iemitsu, Motoyuki; Sanada, Kiyoshi; Gando, Yuko; Ohmori, Yumi; Kawakami, Ryoko; Sasaki, Satoshi; Tabata, Izumi; Miyachi, Motohiko

    2011-12-01

    Elevated fasting plasma homocysteine (Hcy) level is a vascular disease risk factor. Plasma Hcy is affected by 5,10-methylenetetrahydofolate reductase (MTHFR) genotype and dietary folate intake. This cross-sectional study in 434 Japanese adults examined the associations among objectively measured physical activity (PA), plasma Hcy adjusting for dietary folate intake, and MTHFR C677T genotype. Daily PA was measured by triaxial accelerometry and all subjects completed a questionnaire about their dietary habits. Plasma Hcy and MTHFR C677T genotype were determined. Plasma Hcy in subjects with the TT genotype was significantly higher than in those with CC or CT genotype (p < 0.001). Plasma Hcy was significantly different between ≥ 200 (7.6 ± 0.2 nmol/mL) and <200 µg/day (8.3 ± 0.3 nmol/mL) folate intake groups (p = 0.003). There were no differences in plasma Hcy adjusting for age, sex, and folate intake between groups according to PA category in all subjects. However, there were significant interactions between time spent in light PA (p = 0.003), vigorous PA (p = 0.001), or inactivity (p = 0.004), and MTHFR genotype. In only the TT genotype, shorter time spent in light PA was associated with higher plasma Hcy than a longer time spent in light PA (11.5 ± 3.3 nmol/mL vs. 8.5 ± 3.3 nmol/mL, p < 0.001), and longer time spent in vigorous PA and inactivity were associated with higher plasma Hcy (11.8 ± 3.3 nmol/mL vs. 8.4 ± 3.2 nmol/mL, 11.6 ± 3.3 nmol/mL vs. 8.4 ± 3.3 nmol/mL, respectively, p < 0.001). In conclusion, light and vigorous PA were associated with plasma Hcy only in the TT genotype, but there were no such associations in all genotypes.

  15. Controlled shutdown of a fuel cell

    DOEpatents

    Clingerman, Bruce J.; Keskula, Donald H.

    2002-01-01

    A method is provided for the shutdown of a fuel cell system to relieve system overpressure while maintaining air compressor operation, and corresponding vent valving and control arrangement. The method and venting arrangement are employed in a fuel cell system, for instance a vehicle propulsion system, comprising, in fluid communication, an air compressor having an outlet for providing air to the system, a combustor operative to provide combustor exhaust to the fuel processor.

  16. A fast model for spreading of neutral particles injected locally into hot plasma

    SciTech Connect

    Tokar, M. Z.

    2014-08-15

    A fast model for calculation of non-stationary 3-D profiles of the density for neutral particles locally released into a hot plasma is elaborated. The approach reduces non-stationary three-dimensional transport equations to a set of one-dimensional ones describing the time evolution of the radial profiles for several parameters characterizing adequately the three-dimensional structure. The method is applied to model the spreading process of carbon atoms released by laser desorption in an experimental device and the local injection of working gas into a fusion reactor. The associated heat loads onto the first wall are assessed.

  17. Dynamics of dust-free cavities behind fast projectiles in a dusty plasma under microgravity conditions

    SciTech Connect

    Caliebe, D.; Arp, O.; Piel, A.

    2011-07-15

    The penetration of a dusty plasma by fast charged projectiles is studied under microgravity conditions. The mass and charge of the projectiles are larger than those of the target particles. A projectile generates a dust-free cavity in its wake, whose shape strongly depends on the projectile velocity. The faster the projectile the more elongated becomes the cavity while its cross-section decreases. The opening time of the cavity is found independent of the projectile velocity. For supersonic projectiles, the dynamics of the cavity can be decomposed into an initial impulse and a subsequent elastic response that can be modeled by a damped harmonic oscillator.

  18. Photoconductive detectors with fast temporal response for laser produced plasma experiments.

    PubMed

    May, M J; Halvorson, C; Perry, T; Weber, F; Young, P; Silbernagel, C

    2008-10-01

    Processes during laser plasma experiments typically have time scales that are less than 100 ps. The measurement of these processes requires x-ray detectors with fast temporal resolution. We have measured the temporal responses and linearity of several different x-ray sensitive photoconductive detectors (PCDs). The active elements of the detectors investigated include both diamond (natural and synthetic) and GaAs crystals. The typical time responses of the GaAs PCDs are approximately 60 ps, respectively. Some characterizations using x-ray radiation from a synchrotron radiation source are presented.

  19. Photoconductive Detectors with Fast Temporal Response for Laser Produced Plasma Experiments

    SciTech Connect

    M. J. May, C. Halvorson, T. Perry, F. Weber, P. Young, C. Silbernagel

    2008-06-01

    Processes during laser plasma experiments typically have time scales that are less than 100 ps. The measurement of these processes requires X-ray detectors with fast temporal resolution. We have measured the temporal responses and linearity of several different Xray sensitive Photoconductive Detectors (PCDs). The active elements of the detectors investigated include both diamond (natural and synthetic) and GaAs crystals. The typical time responses of the GaAs PCDs are approximately 60 ps, respectively. Some characterizations using X-ray light from a synchrotron light source are presented.

  20. Photoconductive Detectors with Fast Temporal Response for Laser Produced Plasma Experiments.

    SciTech Connect

    May, M; Halvorson, C; Perry, T; Weber, F; Young, P; Silbernagel, C

    2008-05-06

    Processes during laser plasma experiments typically have time scales that are less than 100 ps. The measurement of these processes requires X-ray detectors with fast temporal resolution. We have measured the temporal responses and linearity of several different X-ray sensitive Photoconductive Detectors (PCDs). The active elements of the detectors investigated include both diamond (natural and synthetic) and GaAs crystals. The typical time responses of the GaAs PCDs are approximately 60 ps, respectively. Some characterizations using X-ray light from a synchrotron light source are presented.

  1. Fasting plasma glucose as a screening test for gestational diabetes mellitus.

    PubMed

    Agarwal, Mukesh M; Dhatt, Gurdeep S

    2007-02-01

    Although debated, most preeminent expert panels recommend routine screening for gestational diabetes mellitus (GDM). Among the many tests that have been used and evaluated for the screening of GDM, the fasting plasma glucose (FPG) remains very appealing. It is easy to administer, well tolerated, inexpensive, reproducible and patient friendly. However attractive, the FPG has given varied results in different populations and its use as a screening test for GDM remains uncertain. This review will objectively assess the available studies to find the real value of FPG as a screening test for GDM.

  2. Leukocyte telomere length is inversely associated with post-load but not with fasting plasma glucose levels.

    PubMed

    Khalangot, Mykola; Krasnienkov, Dmytro; Vaiserman, Alexander; Avilov, Ivan; Kovtun, Volodymir; Okhrimenko, Nadia; Koliada, Alexander; Kravchenko, Victor

    2017-04-01

    Type 2 diabetes mellitus is characterized by shorter leukocyte telomere length, but the relationship between leukocyte telomere length and type 2 diabetes mellitus development is rather questioned. Fasting and post-load glycaemia associated with different types of insulin resistance and their relation with leukocyte telomere length remains unknown. We compared leukocyte telomere length and fasting or post-load glucose levels in persons who do not receive glucose lowering treatment. For 82 randomly selected rural residents of Ukraine, aged 45+, not previously diagnosed with type 2 diabetes mellitus, the WHO oral glucose tolerance test and anthropometric measurements were performed. Leukocyte telomere length was measured by standardized method of quantitative monochrome multiplex polymerase chain reaction in real time. Spearman's or Pearson's rank correlation was used for correlation analysis between fasting plasma glucose or 2-h post-load plasma glucose levels and leukocyte telomere length. Logistical regression models were used to evaluate risks of finding short or long telomeres associated with fasting plasma glucose or 2-h post-load plasma glucose levels. No association of fasting plasma glucose and leukocyte telomere length was revealed, whereas 2-h post-load plasma glucose levels demonstrated a negative correlation ( P < 0.01) with leukocyte telomere length. Waist circumference and systolic blood pressure were negatively related ( P = 0.03) with leukocyte telomere length in men. Oral glucose tolerance test result-based glycemic categories did not show differences between mean leukocyte telomere length in categories of normal fasting plasma glucose and 2-h post-load plasma glucose (NGT, n = 33); diabetes mellitus (DM), n = 18 and impaired fasting glucose/tolerance (IFG/IGT, n = 31) levels. A correlation relationship between leukocyte telomere length and 2-h post-load plasma glucose level in NGT; IFG/IGT and DM groups ( P = 0.027; 0

  3. The development and testing of the fast imaging plasma spectrometer and its application in the plasma environment at Mercury

    NASA Astrophysics Data System (ADS)

    Koehn, Patrick Leo

    The plasma environment at Mercury is a rich laboratory for studying the interaction of the solar wind with a planet. Three primary populations of ions exist at Mercury: solar wind, magnetospheric particles, and pickup ions. Pickup ions are generated through the ionization of Mercury's exosphere or are sputtered particles from the Mercury surface. A comprehensive mission to Mercury should include a sensor that is able to determine the dynamical properties and composition of all three plasma components. The Fast Imaging Plasma Spectrometer (FIPS) is an instrument to measure the composition of these ion populations and their three-dimensional velocity distribution functions. It is lightweight, fast, and has a very large field of view, and these properties made possible its accommodation within the highly mass- constrained payload of MESSENGER (MErcury: Surface, Space ENvironment, GEochemistry, Ranging) mission, a Mercury orbiter. This work details the development cycle of FIPS, from concept to prototype testing. It begins with science studies of the magnetospheric and pickup ion environments of Mercury, using state-of-the-art computer simulations to produce static and quasi-dynamic magnetospheric systems. Predictions are made of the spatially variable plasma environment at Mercury, and the temporally varying magnetosphere-solar wind interaction is examined. Pickup ion studies provide insights to particle loss mechanisms and the nature of the radar-bright regions at the Hermean poles. These studies produce science requirements for successfully measuring this environment with an orbiting mass spectrometer. With these science requirements in mind, a concept for a new electrostatic analyzer is created. This concept is considered from a theoretical standpoint, and compared with other, similarly performing instruments, both of the past and currently in use. The development cycle continues with instrument simulation, which allows the design to be adjusted to fit within the

  4. Shear flow instability in a partially-ionized plasma sheath around a fast-moving vehicle

    SciTech Connect

    Sotnikov, V. I.; Mudaliar, S.; Genoni, T. C.; Rose, D. V.; Oliver, B. V.; Mehlhorn, T. A.

    2011-06-15

    The stability of ion acoustic waves in a sheared-flow, partially-ionized compressible plasma sheath around a fast-moving vehicle in the upper atmosphere, is described and evaluated for different flow profiles. In a compressible plasma with shear flow, instability occurs for any velocity profile, not just for profiles with an inflection point. A second-order differential equation for the electrostatic potential of excited ion acoustic waves in the presence of electron and ion collisions with neutrals is derived and solved numerically using a shooting method with boundary conditions appropriate for a finite thickness sheath in contact with the vehicle. We consider three different velocity flow profiles and find that in all cases that neutral collisions can completely suppress the instability.

  5. Plasma flow and fast particles in a hypervelocity accelerator - A color presentation. [micrometeoroid simulation

    NASA Technical Reports Server (NTRS)

    Igenbergs, E. B.; Cour-Palais, B.; Fisher, E.; Stehle, O.

    1975-01-01

    A new concept for particle acceleration for micrometeoroid simulation was developed at NASA Marshall Space Flight Center, using a high-density self-luminescent fast plasma flow to accelerate glass beads (with a diameter up to 1.0 mm) to velocities between 15-20 km/sec. After a short introduction to the operation of the hypervelocity range, the eight-converter-camera unit used for the photographs of the plasma flow and the accelerated particles is described. These photographs are obtained with an eight-segment reflecting pyramidal beam splitter. Wratten filters were mounted between the beam splitter and the converter tubes of the cameras. The photographs, which were recorded on black and white film, were used to make the matrices for the dye-color process, which produced the prints shown.

  6. Magnetized Fast ignition (MFI) and Laser Plasma Interactions in Strong Magnetic Field

    NASA Astrophysics Data System (ADS)

    Mima, Kunioki; Johzaki, T.; Honrubia, J.; Nagatomo, H.; Taguchi, T.; Sunahara, A.; Sakagami, H.; Fujioka, S.; Logan, G.

    2016-03-01

    In this paper, magnetized fast ignition (MFI) is proposed for improving the coupling efficiency of a heating laser to a core plasma. In the MFI, the external magnetic field is applied to reduce the hot electron energy and focus the dense hot electron flux to the core. The external magnetic field higher than 100T is generated by the laser driven coil and it is amplified by the implosion. The magnetic field at the tip of the cone is expected to reach higher than 10kT and the laser plasma interaction and the hot electron transport are modified. As the results of applying the external magnetic field, hot electron energy is reduced to less than 5MeV for the laser intensity of 1020W/ cm2 and the Weibel instability is suppressed to collimate the hot electron beam to the core.

  7. Fast ion generation and bulk plasma heating with three-ion ICRF scenarios

    SciTech Connect

    Kazakov, Ye. O. Van Eester, D.; Ongena, J.; Lerche, E.; Messiaen, A.

    2015-12-10

    Launching electromagnetic waves in the ion cyclotron range of frequencies (ICRF) is an efficient method of plasma heating, actively employed in most of fusion machines. ICRF has a number of important supplementary applications, including the generation of high-energy ions. In this paper, we discuss a new set of three-ion ICRF scenarios and the prospect of their use as a dedicated tool for fast ion generation in tokamaks and stellarators. A distinct feature of these scenarios is a strong absorption efficiency possible at very low concentrations of resonant minority ions (∼ 1% or even below). Such concentration levels are typical for impurities contaminating fusion plasmas. An alternative ICRF scenario for maximizing the efficiency of bulk D-T ion heating is suggested for JET and ITER tokamaks, which is based on three-ion ICRF heating of intrinsic Beryllium impurities.

  8. Be Foil "Filter Knee Imaging" NSTX Plasma with Fast Soft X-ray Camera

    SciTech Connect

    B.C. Stratton; S. von Goeler; D. Stutman; K. Tritz; L.E. Zakharov

    2005-08-08

    A fast soft x-ray (SXR) pinhole camera has been implemented on the National Spherical Torus Experiment (NSTX). This paper presents observations and describes the Be foil Filter Knee Imaging (FKI) technique for reconstructions of a m/n=1/1 mode on NSTX. The SXR camera has a wide-angle (28{sup o}) field of view of the plasma. The camera images nearly the entire diameter of the plasma and a comparable region in the vertical direction. SXR photons pass through a beryllium foil and are imaged by a pinhole onto a P47 scintillator deposited on a fiber optic faceplate. An electrostatic image intensifier demagnifies the visible image by 6:1 to match it to the size of the charge-coupled device (CCD) chip. A pair of lenses couples the image to the CCD chip.

  9. Plasma flow and fast particles in a hypervelocity accelerator - A color presentation. [micrometeoroid simulation

    NASA Technical Reports Server (NTRS)

    Igenbergs, E. B.; Cour-Palais, B.; Fisher, E.; Stehle, O.

    1975-01-01

    A new concept for particle acceleration for micrometeoroid simulation was developed at NASA Marshall Space Flight Center, using a high-density self-luminescent fast plasma flow to accelerate glass beads (with a diameter up to 1.0 mm) to velocities between 15-20 km/sec. After a short introduction to the operation of the hypervelocity range, the eight-converter-camera unit used for the photographs of the plasma flow and the accelerated particles is described. These photographs are obtained with an eight-segment reflecting pyramidal beam splitter. Wratten filters were mounted between the beam splitter and the converter tubes of the cameras. The photographs, which were recorded on black and white film, were used to make the matrices for the dye-color process, which produced the prints shown.

  10. Fast electron energy deposition in a magnetized plasma: Kinetic theory and particle-in-cell simulation

    SciTech Connect

    Robiche, J.; Rax, J.-M.; Bonnaud, G.; Gremillet, L.

    2010-03-15

    The collisional dynamics of a relativistic electron jet in a magnetized plasma are investigated within the framework of kinetic theory. The relativistic Fokker-Planck equation describing slowing down, pitch angle scattering, and cyclotron rotation is derived and solved. Based on the solution of this Fokker-Planck equation, an analytical formula for the root mean square spot size transverse to the magnetic field is derived and this result predicts a reduction in radial transport. Some comparisons with particle-in-cell simulation are made and confirm striking agreement between the theory and the simulation. For fast electron with 1 MeV typical kinetic energy interacting with a solid density hydrogen plasma, the energy deposition density in the transverse direction increases by a factor 2 for magnetic field of the order of 1 T. Along the magnetic field, the energy deposition profile is unaltered compared with the field-free case.

  11. Fast ion generation and bulk plasma heating with three-ion ICRF scenarios

    NASA Astrophysics Data System (ADS)

    Kazakov, Ye. O.; Van Eester, D.; Dumont, R.; Ongena, J.; Lerche, E.; Messiaen, A.

    2015-12-01

    Launching electromagnetic waves in the ion cyclotron range of frequencies (ICRF) is an efficient method of plasma heating, actively employed in most of fusion machines. ICRF has a number of important supplementary applications, including the generation of high-energy ions. In this paper, we discuss a new set of three-ion ICRF scenarios and the prospect of their use as a dedicated tool for fast ion generation in tokamaks and stellarators. A distinct feature of these scenarios is a strong absorption efficiency possible at very low concentrations of resonant minority ions (˜ 1% or even below). Such concentration levels are typical for impurities contaminating fusion plasmas. An alternative ICRF scenario for maximizing the efficiency of bulk D-T ion heating is suggested for JET and ITER tokamaks, which is based on three-ion ICRF heating of intrinsic Beryllium impurities.

  12. Plasma-beta dependence of the fast reconnection mechanism in an initially force-free current sheet

    SciTech Connect

    Ugai, M.

    2011-10-15

    The present paper systematically studies the spontaneous fast reconnection mechanism in an initially force-free current sheet in a wide range of plasma beta ({beta}); in our previous work it was studied for a special case of {beta} = 0.15. In each case, the evolution as well as the resulting structure of the fast reconnection is qualitatively similar to the one that was already reported for the case of {beta} = 0.15. Quantitatively, the fast reconnection evolution becomes more rapid and drastic for the lower plasma beta. For the cases of very low plasma beta ({beta} = 0.01 or 0.02), the plasma temperature is extremely enhanced to the value almost 1/{beta} times larger than its initial value in the resulting fast reconnection jet and large-scale plasmoid regions. Once the fast reconnection mechanism is ignited in a local spot-like region, its basic structure eventually established is sustained almost steadily, giving rise to the plasmoid swelling with time and propagating outwards. Accordingly, the characteristic reconnection regions, where plasma thermodynamic quantities are remarkably enhanced, rapidly expand in all (x, y, and z) directions in Alfven time scales, which may be responsible for the explosive expansion of large flares as well as for the distinct plasma heating observed in the solar corona.

  13. Genome-wide linkage analysis replicates susceptibility locus for fasting plasma triglycerides: NHLBI Family Heart Study.

    PubMed

    Arnett, Donna K; Miller, Michael B; Coon, Hilary; Ellison, R Curtis; North, Kari E; Province, Michael; Leppert, Mark; Eckfeldt, John H

    2004-11-01

    Recent reports implicate chromosomal regions linked to inter-individual variation in plasma triglycerides. We conducted genome-wide scans to replicate these linkages and/or identify other loci influencing plasma triglycerides in the NHLBI Family Heart Study (FHS). Data were obtained for 501 three-generational families. Genotyping was done by the Utah Molecular Genetics Laboratory and NHLBI Mammalian Genotyping Service; markers from both were placed on one genetic map. Analysis was done using multipoint variance components linkage. Fasting plasma triglycerides were log-transformed and age-, sex-, and field center-adjusted; suggestive linkage evidence was found on chromosome 8 (LOD=2.80 at 89 cM, marker D8S1141). Further adjustment for waist girth, BMI, diabetes, hypertension, and lipid-lowering drugs suggested linkage regions on chromosomes 6 (LOD=2.29 at 79 cM, marker D6S295) and 15 (LOD=1.85 at 43 cM, marker D15S659). Since HDL is correlated with triglycerides and because it was linked to this region on chromosome 15 in FHS, we created a composite triglyceride-HDL phenotype. The combined phenotype LOD score was 3.0 at the same marker on chromosome 15. Chromosome 15 likely harbors a susceptibility locus with an influence on triglycerides and HDL. Regions on chromosomes 6 and 8 may also contain loci contributing to inter-individual variation in plasma triglycerides.

  14. Generation of plasma rotation in a tokamak by ion-cyclotron absorption of fast Alfven waves

    SciTech Connect

    F.W. Perkins; R.B. White; P. Bonoli

    2000-06-13

    Control of rotation in tokamak plasmas provides a method for suppressing fine-scale turbulent transport by velocity shear and for stabilizing large-scale magnetohydrodynamic instabilities via a close-fitting conducting shell. The experimental discovery of rotation in a plasma heated by the fast-wave minority ion cyclotron process is important both as a potential control method for a fusion reactor and as a fundamental issue, because rotation arises even though this heating process introduces negligible angular momentum. This paper proposes and evaluates a mechanism which resolves this apparent conflict. First, it is assumed that angular momentum transport in a tokamak is governed by a diffusion equation with a no-slip boundary condition at the plasma surface and with a torque-density source that is a function of radius. When the torque density source consists of two separated regions of positive and negative torque density, a non-zero central rotation velocity results, even when the total angular momentum input vanishes. Secondly, the authors show that localized ion-cyclotron heating can generate regions of positive and negative torque density and consequently central plasma rotation.

  15. Laser Channeling in an Inhomogeneous Plasma for Fast-Ignition Laser Fusion

    NASA Astrophysics Data System (ADS)

    Ivancic, S.; Haberberger, D.; Theobald, W.; Anderson, K. S.; Froula, D. H.; Meyerhofer, D. D.; Tanaka, K.; Habara, H.; Iwawaki, T.

    2014-10-01

    The evacuation of a plasma cavity by a high-intensity laser beam is of practical importance to the channeling fast-ignition concept. The channel in the plasma corona of an imploded inertial confinement fusion capsule provides a clear path through the plasma so that the energy from a second high-intensity laser can be deposited close to the dense core of the assembled fuel to achieve ignition. This study reports on experiments that demonstrate the transport of high-intensity (>1017 W/cm2) laser light through an inhomogeneous kilojoule-laser-produced plasma up to overcritical density. The multikilojoule high-intensity light evacuates a cavity inside the focal spot, leaving a parabolic trough that is observed using a novel optical probing technique--angular filter refractometery. The cavity forms in less than 100 ps using a 20-TW laser pulse and bores at a velocity of ~ 2 μm/ps. The experimentally measured depths of the cavity are consistent with a ponderomotive hole-boring model. The experiments show that 100-ps IR pulses with an intensity of ~ 5 ×1017 W/cm2 produced a channel up to the critical density, while 10-ps pulses with the same energy but higher intensity did not propagate as far. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  16. Nonlinear resonant absorption of fast magnetoacoustic waves in strongly anisotropic and dispersive plasmas

    SciTech Connect

    Clack, Christopher T. M.; Ballai, Istvan

    2009-04-15

    The nonlinear theory of driven magnetohydrodynamics (MHD) waves in strongly anisotropic and dispersive plasmas, developed for slow resonance by Clack and Ballai [Phys. Plasmas 15, 2310 (2008)] and Alfven resonance by Clack et al. [Astron. Astrophys. 494, 317 (2009)], is used to study the weakly nonlinear interaction of fast magnetoacoustic (FMA) waves in a one-dimensional planar plasma. The magnetic configuration consists of an inhomogeneous magnetic slab sandwiched between two regions of semi-infinite homogeneous magnetic plasmas. Laterally driven FMA waves penetrate the inhomogeneous slab interacting with the localized slow or Alfven dissipative layer and are partly reflected, dissipated, and transmitted by this region. The nonlinearity parameter defined by Clack and Ballai (2008) is assumed to be small and a regular perturbation method is used to obtain analytical solutions in the slow dissipative layer. The effect of dispersion in the slow dissipative layer is to further decrease the coefficient of energy absorption, compared to its standard weakly nonlinear counterpart, and the generation of higher harmonics in the outgoing wave in addition to the fundamental one. The absorption of external drivers at the Alfven resonance is described within the linear MHD with great accuracy.

  17. COS FUV Recovery after Anomalous Shutdown

    NASA Astrophysics Data System (ADS)

    Wheeler, Thomas

    2013-10-01

    This proposal consists of the steps for turning on and ramping up the COS FUV high voltage in a safe and conservative manner after a HV anomalous shutdown by executing a "reduced set" of visits from Cycle 19 Proposal 12810. The nature of the shutdown, i.e., over-light, HV current transient {"crackle"}, ion feedback {induced by a high energy particle}, or field emission {possibly caused by dust or other particulate on the QE grid or other close-by structure or hardware}, and the value of the commanded HV at the time of the shutdown will determine what visits are executed. Because of gain sag, commanded HV settings updates may be required. First, prior to execution of this proposal or selected visits from this proposal, all preliminary steps should be exercised to gather the necessary diagnostic data, e.g., science data evaluation {if a science exposure was in progress and the science data is available}, memory dumps {DCE, EXEC RAM, and possibly the CS BUFFER}, engineering telemetry, or other information that might provide insight as to the nature of the shutdown and estimated count rate. The complete step-by-step procedure is detailed in the Observing Description, but in summary, the following is done:Day 01 activities, visits 01-07, contain both QE grid off and on HV ramping to HVLow {100/100} with diagnostics {DCE dumps} and darks to exclude QE grid involvement in the shutdown. Subsequent to day 01, all HV ramping will be with the QE grid on with the same diagnostics and exposures. All days end with the setting of COS event flag 3 to prevent any FUV HV commanding.Time is allotted for cognizant detector and COS instrument scientist and engineers to examine data dumps, science exposures, and engineering telemetry. If all is well, the go-ahead will be given to clear flag 3 for the next day's visits.This proposal is modeled after the Cycle 20 Proposal 13129.

  18. Reliability of fasting plasma alkylresorcinol metabolites concentrations measured 4 months apart.

    PubMed

    Montonen, J; Landberg, R; Kamal-Eldin, A; Åman, P; Boeing, H; Steffen, A; Pischon, T

    2012-08-01

    Alkylresorcinols (AR) have been suggested as specific dietary biomarkers of whole-grain wheat and rye intake. AR are metabolised to 3,5-dihydroxybenzoic acid (DHBA) and 3-(3,5-dihydroxyphenyl)-1-propanoic acid (DHPPA), which have longer apparent half-lives and were recently proposed to better reflect long-term whole-grain consumption than the intact AR. The objective of this study was to analyse the reliability--expressed by the intraclass correlation coefficient (ICC)--of AR metabolite concentrations among 100 participants from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam study who provided two fasting plasma samples 4 months apart. DHBA and DHPPA concentrations were not significantly different between the first and second measurement over the 4-month period (P>0.05). The ICC was 0.32 (95% confidence interval (CI)=0.13-0.49) for DHBA and 0.37 (95%CI=0.19-0.53) for DHPPA. These results suggest that AR metabolites cannot be considered to be better biomarkers of whole-grain wheat and rye intake than the intact AR in fasting plasma (ICC=0.42).

  19. Renal responses to plasma volume expansion and hyperosmolality in fasting seal pups

    NASA Technical Reports Server (NTRS)

    Ortiz, Rudy M.; Wade, Charles E.; Costa, Daniel P.; Ortiz, C. Leo

    2002-01-01

    Renal responses were quantified in northern elephant seal (Mirounga angustirostris) pups during their postweaning fast to examine their excretory capabilities. Pups were infused with either isotonic (0.9%; n = 8; Iso) or hypertonic (16.7%; n = 7; Hyper) saline via an indwelling catheter such that each pup received 3 mmol NaCl/kg. Diuresis after the infusions was similar in magnitude between the two treatments. Osmotic clearance increased by 37% in Iso and 252% in Hyper. Free water clearance was reduced 3.4-fold in Hyper but was not significantly altered in Iso. Glomerular filtration rate increased 71% in the 24-h period after Hyper, but no net change occurred during the same time after Iso. Natriuresis increased 3.6-fold in Iso and 5.3-fold in Hyper. Iso decreased plasma arginine vasopressin (AVP) and cortisol acutely, whereas Hyper increased plasma and excreted AVP and cortisol. Iso was accompanied by the retention of water and electrolytes, whereas the Hyper load was excreted within 24 h. Natriuresis is attributed to increased filtration and is independent of an increase in atrial natriuretic peptide and decreases in ANG II and aldosterone. Fasting pups appear to have well-developed kidneys capable of both extreme conservation and excretion of Na(+).

  20. Renal responses to plasma volume expansion and hyperosmolality in fasting seal pups

    NASA Technical Reports Server (NTRS)

    Ortiz, Rudy M.; Wade, Charles E.; Costa, Daniel P.; Ortiz, C. Leo

    2002-01-01

    Renal responses were quantified in northern elephant seal (Mirounga angustirostris) pups during their postweaning fast to examine their excretory capabilities. Pups were infused with either isotonic (0.9%; n = 8; Iso) or hypertonic (16.7%; n = 7; Hyper) saline via an indwelling catheter such that each pup received 3 mmol NaCl/kg. Diuresis after the infusions was similar in magnitude between the two treatments. Osmotic clearance increased by 37% in Iso and 252% in Hyper. Free water clearance was reduced 3.4-fold in Hyper but was not significantly altered in Iso. Glomerular filtration rate increased 71% in the 24-h period after Hyper, but no net change occurred during the same time after Iso. Natriuresis increased 3.6-fold in Iso and 5.3-fold in Hyper. Iso decreased plasma arginine vasopressin (AVP) and cortisol acutely, whereas Hyper increased plasma and excreted AVP and cortisol. Iso was accompanied by the retention of water and electrolytes, whereas the Hyper load was excreted within 24 h. Natriuresis is attributed to increased filtration and is independent of an increase in atrial natriuretic peptide and decreases in ANG II and aldosterone. Fasting pups appear to have well-developed kidneys capable of both extreme conservation and excretion of Na(+).

  1. On-board moments from Magnetospheric Multiscale's Fast Plasma Instrumentation in studies of turbulence

    NASA Astrophysics Data System (ADS)

    Paterson, William R.; Giles, Barbara L.; Avanov, Levon A.; Barrie, Alex C.; Boardsen, Scott A.; Dorelli, John C.; Gershman, Daniel J.; Mackler, David A.; El-Alaoui, Mostafa; Burch, James L.; Russell, Christopher T.; Torbert, Roy B.

    2017-04-01

    The Fast Plasma Instrumentation for the Magnetospheric Multiscale mission measures the velocity distributions of electrons and ions with energies several eV to 30 keV. In its fast survey mode of operation, velocity distributions are acquired every 30 ms for the electrons and every 150 ms for the ions. Due to telemetry limitations, only a small subset of these distributions can be transmitted to the ground. To facilitate selection of intervals with high potential for addressing magnetic reconnection, a compact set of approximate plasma moments is computed onboard the spacecraft and sent to the ground at the full temporal resolution of the instrumentation. Although these moments were not intended for direct use in scientific investigations, they have the advantage of being the only FPI data product that is available at high time resolution across the entire scientific region of interest. In this presentation we report on prospects for using these data to address scientific questions, with emphasis on studies of turbulence.

  2. The 2013 US Government Shutdown (#Shutdown) and Health: An Emerging Role for Social Media

    PubMed Central

    Ha, Yoonhee P.; Wong, Charlene A.; Schwartz, H. Andrew; Sap, Maarten; Ungar, Lyle H.; Asch, David A.

    2014-01-01

    In October 2013, multiple United States (US) federal health departments and agencies posted on Twitter, “We’re sorry, but we will not be tweeting or responding to @replies during the shutdown. We’ll be back as soon as possible!” These “last tweets” and the millions of responses they generated revealed social media’s role as a forum for sharing and discussing information rapidly. Social media are now among the few dominant communication channels used today. We used social media to characterize the public discourse and sentiment about the shutdown. The 2013 shutdown represented an opportunity to explore the role social media might play in events that could affect health. PMID:25322303

  3. Diagnostics of fast formation of distributed plasma discharges using X-band microwaves

    SciTech Connect

    Xiang, X. Kupczyk, B.; Booske, J.; Scharer, J.

    2014-02-14

    We present measurements of high power (25.7 kW), pulsed (800 ns), X-band (9.382 GHz) microwave breakdown plasmas, including reflected power measurements, mixer reflected amplitude and phase measurements, optical emission spectroscopy (OES) measurements, and an analysis that estimates the average electron density and electron temperature. In addition, a six-region, 1-D model was used to determine plasma parameters and compare with the experimental results. The experimental results show that using a 43 Hz repetition rate with an 800 ns pulse, fast (<300 ns) breakdown occurs in neon measured between 50 Torr and 250 Torr, producing plasma that lasts for over 7 μs. It also leads to large microwave reflections (70%) and an on-axis transmission attenuation of −15 dB. Moreover, a comparison between a 1-D model and mixer measurements shows that at 100 Torr, the neon plasma electron density peaked at 2 × 10{sup 12} cm{sup −3}, and the electron temperature peaked at 2.5 eV assuming a Maxwellian distribution. The addition of 2% Ar in Ne reduced the breakdown time and allowed OES measurements to determine the effective electron temperature. OES measurements of mixed (Ne/Ar: 98/2) argon line ratios (420.1 nm/419.8 nm) were used to determine the average effective electron temperature T{sub e(eff)} = 1.2 eV, averaged over the entire 7μs plasma lifetime. They indicate that the electron energy distribution was not Maxwellian but, instead, tended towards a Druyvesteyn character.

  4. Fasting and exercise increase plasma cannabinoid levels in THC pre-treated rats: an examination of behavioural consequences.

    PubMed

    Wong, Alexander; Keats, Kirily; Rooney, Kieron; Hicks, Callum; Allsop, David J; Arnold, Jonathon C; McGregor, Iain S

    2014-10-01

    Δ(9)-Tetrahydrocannabinol (THC), the main psychoactive constituent of cannabis, accumulates in fat tissue where it can remain for prolonged periods. Under conditions of increased fat utilisation, blood cannabinoid concentrations can increase. However, it is unclear whether this has behavioural consequences. Here, we examined whether rats pre-treated with multiple or single doses of THC followed by a washout would show elevated plasma cannabinoids and altered behaviour following fasting or exercise manipulations designed to increase fat utilisation. Behavioural impairment was measured as an inhibition of spontaneous locomotor activity or a failure to successfully complete a treadmill exercise session. Fat utilisation was indexed by plasma free fatty acid (FFA) levels with plasma concentrations of THC and its terminal metabolite (-)-11-nor-9-carboxy-∆(9)-tetrahydrocannabinol (THC-COOH) also measured. Rats given daily THC (10 mg/kg) for 5 days followed by a 4-day washout showed elevated plasma THC-COOH when fasted for 24 h relative to non-fasted controls. Fasted rats showed lower locomotor activity than controls suggesting a behavioural effect of fat-released THC. However, rats fasted for 20 h after a single 5-mg/kg THC injection did not show locomotor suppression, despite modestly elevated plasma THC-COOH. Rats pre-treated with THC (5 mg/kg) and exercised 20 h later also showed elevated plasma THC-COOH but did not differ from controls in their likelihood of completing 30 min of treadmill exercise. These results confirm that fasting and exercise can increase plasma cannabinoid levels. Behavioural consequences are more clearly observed with pre-treatment regimes involving repeated rather than single THC dosing.

  5. Effect of the long-term regular intake of virgin olive oil on the phenolic metabolites in human fasting plasma.

    PubMed

    Valls, Rosa-Maria; Soler, Aranzazu; Girona, Josefa; Heras, Mercedes; Romero, Maria-Paz; Covas, Maria-Isabel; Solà, Rosa; Masana, Lluis; Motilva, Maria-Jose

    2010-09-21

    The effect of repeated consumption of virgin olive oil on endogenous phenolic metabolites of fasting plasma is unknown. For this reason, we hypothesized that regular long-term virgin olive oil intake could have an indirect protection effect on the endogenous phenols. Thus, the aim of the study was to determine the phenolic profile of human plasma in a fasting state of long-term regular virgin olive oil consumers, using the fasting plasma of non-consumers as a natural control. Forty participants living in the area of Reus (Catalonia, Spain) were selected, 20 life-long regular consumers of virgin olive oil and a natural control of 20 non-consumers, the latter being Rumanians who dislike the taste of olive oil. The diet was obtained from 3-day food records. The results showed similar phenolic composition of fasting plasmas of the two volunteer groups. Of special interest is that more of the compounds quantified showed higher concentration in fasting plasma from habitual virgin olive oil consumers. The compounds were semi-quantified using caffeic acid as the calibration standard. The quantification of fasting consumer's plasma showed higher concentration of a hydroxyflavanone type compound (2.90+/-0.04 microM vs 1.5+/-0.04 microM) and a catecholamine derivative (0.70+/-0.03 microM vs 0.56+/-0.03 microM) than the plasma of non-consumers (P<0.05). The results suggest an indirect protective mechanism of long-term regular virgin olive oil consumption related to the protection of the endogenous antioxidant system.

  6. Metabonomic fingerprints of fasting plasma and spot urine reveal human pre-diabetic metabolic traits

    PubMed Central

    Zhao, Xinjie; Fritsche, Jens; Wang, Jiangshan; Chen, Jing; Rittig, Kilian; Schmitt-Kopplin, Philippe; Fritsche, Andreas; Häring, Hans-Ulrich; Schleicher, Erwin D.

    2010-01-01

    Impaired glucose tolerance (IGT) which precedes overt type 2 diabetes (T2DM) for decades is associated with multiple metabolic alterations in insulin sensitive tissues. In an UPLC-qTOF-mass spectrometry-driven non-targeted metabonomics approach we investigated plasma as well as spot urine of 51 non-diabetic, overnight fasted individuals aiming to separate subjects with IGT from controls thereby identify pathways affected by the pre-diabetic metabolic state. We could clearly demonstrate that normal glucose tolerant (NGT) and IGT subjects clustered in two distinct groups independent of the investigated metabonome. These findings reflect considerable differences in individual metabolite fingerprints, both in plasma and urine. Pre-diabetes associated alterations in fatty acid-, tryptophan-, uric acid-, bile acid-, and lysophosphatidylcholine-metabolism, as well as the TCA cycle were identified. Of note, individuals with IGT also showed decreased levels of gut flora-associated metabolites namely hippuric acid, methylxanthine, methyluric acid, and 3-hydroxyhippuric acid. The findings of our non-targeted UPLC-qTOF-MS metabonomics analysis in plasma and spot urine of individuals with IGT vs NGT offers novel insights into the metabolic alterations occurring in the long, asymptomatic period preceding the manifestation of T2DM thereby giving prospects for new intervention targets. Electronic supplementary material The online version of this article (doi:10.1007/s11306-010-0203-1) contains supplementary material, which is available to authorized users. PMID:20676218

  7. Fast magnetic twister and plasma perturbations in a three-dimensional coronal arcade

    SciTech Connect

    Murawski, K.; Srivastava, A. K.; Musielak, Z. E. E-mail: asrivastava.app@iitbhu.ac.in E-mail: musielak@kis.uni-freiburg.de

    2014-06-10

    We present results of three-dimensional (3D) numerical simulations of a fast magnetic twister excited above a foot-point of the potential solar coronal arcade that is embedded in the solar atmosphere with the initial VAL-IIIC temperature profile, which is smoothly extended into the solar corona. With the use of the FLASH code, we solve 3D ideal magnetohydrodynamic equations by specifying a twist in the azimuthal component of magnetic field in the solar chromosphere. The imposed perturbation generates torsional Alfvén waves as well as plasma swirls that reach the other foot-point of the arcade and partially reflect back from the transition region. The two vortex channels are evident in the generated twisted flux-tube with a fragmentation near its apex which results from the initial twist as well as from the morphology of the tube. The numerical results are compared to observational data of plasma motions in a solar prominence. The comparison shows that the numerical results and the data qualitatively agree even though the observed plasma motions occur over comparatively large spatio-temporal scales in the prominence.

  8. Simulation of high-energy proton production by fast magnetosonic shock waves in pinched plasma discharges

    NASA Astrophysics Data System (ADS)

    Mizuguchi, Yusuke; Sakai, Jun-Ichi; Yousefi, Hamid Reza; Haruki, Takayuki; Masugata, Katsumi

    2007-03-01

    High-energy particles of a few hundred keV for electrons and up to MeV for ions were observed in a plasma focus device. Haruki et al. [Phys. Plasmas 13, 082106-1 (2006)] studied the mechanism of high-energy particle production in pinched plasma discharges by use of a 3D relativistic and fully electromagnetic particle-in-cell code. It was found that the pinched current is unstable against a sausage instability, and then becomes unstable against a kink instability. As a result high-energy electrons were observed, but protons with MeV energies were not observed. In this paper the same pinch dynamics as Haruki and co-workers is investigated, focusing on the shock formation and the shock acceleration during the pinched current. It is found that a fast magnetosonic shock wave is produced during the pinching phase which, after the maximum pinch occurs, is strongly enhanced and propagates outwards. Some protons trapped in the electrostatic potential produced near the shock front can be accelerated to a few MeV by the surfatron acceleration mechanism. It is also found that the protons accelerated along the pinched axis have a ring-shaped angular distribution that is observed from numerous experiments.

  9. Quality assurance program plan fuel supply shutdown

    SciTech Connect

    Metcalf, I.L.

    1998-09-21

    This Quality Assurance Program plan (QAPP) describes how the Fuel Supply Shutdown (FSS) project organization implements the quality assurance requirements of HNF-MP-599, Project Hanford Quality Assurance Program Description (QAPD) and the B and W Hanford Company Quality Assurance Program Plan (QAPP), FSP-MP-004. The QAPP applies to facility structures, systems, and components and to activities (e.g., design, procurement, testing, operations, maintenance, etc.) that could affect structures, systems, and components. This QAPP also provides a roadmap of applicable Project Hanford Policies and Procedures (PHPP) which may be utilized by the FSS project organization to implement the requirements of this QAPP.

  10. Experimental area power monitoring during shutdown

    SciTech Connect

    Pathiyil, J.

    1989-03-01

    The power consumption at the site is increasing every year and the power consumption in the fixed target beam lines is constantly changing for each run. Since we do not have an energy monitoring program in effect in the experimental areas; we are not in a position to tell whether we are using the electrical energy efficiently. The purpose of this study is to find the summer and winter base load of the three experimental areas while the beamlines are off and also to identify what kind loads are on. The most important purpose was to find the base loads in each of the big experimental halls during the shutdown.

  11. Rodded shutdown system for a nuclear reactor

    DOEpatents

    Golden, Martin P.; Govi, Aldo R.

    1978-01-01

    A top mounted nuclear reactor diverse rodded shutdown system utilizing gas fed into a pressure bearing bellows region sealed at the upper extremity to an armature. The armature is attached to a neutron absorber assembly by a series of shafts and connecting means. The armature is held in an uppermost position by an electromagnet assembly or by pressurized gas in a second embodiment. Deenergizing the electromagnet assembly, or venting the pressurized gas, causes the armature to fall by the force of gravity, thereby lowering the attached absorber assembly into the reactor core.

  12. Technical Assessment: WRAP 1 HVAC Passive Shutdown

    SciTech Connect

    Ball, D.E.; Nash, C.R.; Stroup, J.L.

    1993-08-12

    As the result of careful interpretation of DOE Order 6430.lA and other DOE Orders, the HVAC system for WRAP 1 has been greatly simplified. The HVAC system is now designed to safely shut down to Passive State if power fails for any reason. The fans cease functioning, allowing the Zone 1 and Zone 2 HVAC Confinement Systems to breathe with respect to atmospheric pressure changes. Simplifying the HVAC system avoided overdesign. Construction costs were reduced by eliminating unnecessary equipment. This report summarizes work that was done to define the criteria, physical concepts, and operational experiences that lead to the passive shutdown design for WRAP 1 confinement HVAC systems.

  13. Radiation asymmetry and MHD activity in gas jet rapid shutdowns on Alcator C-Mod

    NASA Astrophysics Data System (ADS)

    Olynyk, Geoffrey; Granetz, Robert; Whyte, Dennis; Alcator C-Mod Team

    2013-10-01

    Radiative rapid shutdown via massive noble gas injection (MGI) is an integral part of the ITER disruption mitigation system (DMS). However, observations have shown that the radiation during MGI rapid shutdowns may be spatially asymmetric, particularly during the initial phase when the plasma's thermal energy is converted to radiation. ITER requires the radiation peaking factor (PF) to be less than approximately 2.0 to 2.5 in this thermal quench (TQ) phase in order to prevent melting of the beryllium wall even in the case of a successful MGI rapid shutdown. We report on observations of rotating MHD modes in single- and multiple-gas-jet rapid shutdowns on Alcator C-Mod, and discuss the role of mode rotation during the TQ in setting the radiation peaking factor. The implications for the ITER DMS are discussed. This work was supported by the United States Department of Energy under Contract No. DE-FC02-99ER54512 and the Natural Sciences and Engineering Research Council of Canada PGS D program.

  14. Relationships between fasting plasma insulin, anthropometrics, and metabolic parameters in a very old healthy population. Associazione Medica Sabin.

    PubMed

    Carantoni, M; Zuliani, G; Volpato, S; Palmieri, E; Mezzetti, A; Vergnani, L; Fellin, R

    1998-05-01

    Several studies have shown that insulin resistance and hyperinsulinemia are associated with many metabolic disorders predisposing to coronary heart disease (CHD). This syndrome has been termed syndrome X. However, it is not completely known whether these relationships are still present in the elderly, or whether other factors such as age, gender, and body fat distribution modulate them. Therefore, we investigated the relationship between fasting plasma insulin, total and regional adiposity, fasting plasma glucose and lipids, plasma plasminogen activator inhibitor-1 (PAI-1), fibrinogen, and coagulation factor VII in a sample of 100 healthy free-living octogenarians-nonagenarians (52 men and 48 women) who were disability-free according to the Katz index. By univariate analysis, fasting insulin correlated positively with all anthropometric measures except the waist to hip ratio (WHR) in women. There was a positive correlation between fasting insulin and fasting glucose (r=.40, P < .01), plasma triglycerides ([TGs] r=.21, P < .05), and PAI-1 levels (r=.33, P < .01), whereas a negative relation was found with high-density lipoprotein cholesterol (HDL-C) and apolipoprotein, A-I (apo A-I) levels (r=-.22 and =-.24, respectively, P < .05). These relationships were weaker and less significant in women. In pooled data, stepwise multiple regression analysis showed an independent relationship of both the body mass index (BMI) and fasting insulin level with TGs (R2=.14), while gender and fasting insulin were the best predictors of HDL-C variance (R2=.17). Furthermore, fasting insulin was the only variable independently related to PAI-1 (R2=.12). Our findings support the existence of a metabolic syndrome even in very old age by showing that high insulin levels are related to various metabolic and hemostatic disorders.

  15. MHD study of three-dimensional spontaneous fast magnetic reconnection for cross-tail plasma inflows in magnetotail

    NASA Astrophysics Data System (ADS)

    Shimizu, Tohru; Torii, Hiroyuki; Kondoh, Koji

    2016-05-01

    The 3D instability of spontaneous fast magnetic reconnection process is studied with magnetohydrodynamic simulations, where 2D model of the spontaneous fast magnetic reconnection process is destabilized in three dimensions. In this 3D instability, the spontaneous fast magnetic reconnection process is intermittently and randomly caused in 3D. In this paper, as a typical event study, a single 3D fast magnetic reconnection process often observed in the 3D instability is studied in detail. As a remarkable feature, it is reported that, when the 3D fast magnetic reconnection process starts, plasma inflows along the magnetic neutral line are observed, which are driven by plasma static pressure gradient along the neutral line. The plasma inflow speed reaches about 15 in the upstream field region. The unmagnetized inflow tends to prevent the 3D reconnection process; nevertheless, the 3D reconnection process is intermittently maintained. Such high-speed plasma inflows along the neutral line may be observed as dawn-dusk flows in space satellite observations of magnetotail's bursty bulk flows.

  16. 49 CFR 192.167 - Compressor stations: Emergency shutdown.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY... Components § 192.167 Compressor stations: Emergency shutdown. (a) Except for unattended field compressor...

  17. Investigating plasma viscosity with fast framing photography in the ZaP-HD Flow Z-Pinch experiment

    NASA Astrophysics Data System (ADS)

    Weed, Jonathan Robert

    The ZaP-HD Flow Z-Pinch experiment investigates the stabilizing effect of sheared axial flows while scaling toward a high-energy-density laboratory plasma (HEDLP > 100 GPa). Stabilizing flows may persist until viscous forces dissipate a sheared flow profile. Plasma viscosity is investigated by measuring scale lengths in turbulence intentionally introduced in the plasma flow. A boron nitride turbulence-tripping probe excites small scale length turbulence in the plasma, and fast framing optical cameras are used to study time-evolved turbulent structures and viscous dissipation. A Hadland Imacon 790 fast framing camera is modified for digital image capture, but features insufficient resolution to study turbulent structures. A Shimadzu HPV-X camera captures the evolution of turbulent structures with great spatial and temporal resolution, but is unable to resolve the anticipated Kolmogorov scale in ZaP-HD as predicted by a simplified pinch model.

  18. Stable isotope models of sugar intake using hair, red blood cells, and plasma, but not fasting plasma glucose, predict sugar intake in a Yup'ik study population.

    PubMed

    Nash, Sarah H; Kristal, Alan R; Hopkins, Scarlett E; Boyer, Bert B; O'Brien, Diane M

    2014-01-01

    Objectively measured biomarkers will help to resolve the controversial role of sugar intake in the etiology of obesity and related chronic diseases. We recently validated a dual-isotope model based on RBC carbon (δ(13)C) and nitrogen (δ(15)N) isotope ratios that explained a large percentage of the variation in self-reported sugar intake in a Yup'ik study population. Stable isotope ratios can easily be measured from many tissues, including RBCs, plasma, and hair; however, it is not known how isotopic models of sugar intake compare among these tissues. Here, we compared self-reported sugar intake with models based on RBCs, plasma, and hair δ(13)C and δ(15)N in Yup'ik people. We also evaluated associations of sugar intake with fasting plasma glucose δ(13)C. Finally, we evaluated relations between δ(13)C and δ(15)N values in hair, plasma, RBCs, and fasting plasma glucose to allow comparison of isotope ratios across tissue types. Models using RBCs, plasma, or hair isotope ratios explained similar amounts of variance in total sugar, added sugar, and sugar-sweetened beverage intake (∼53%, 48%, and 34%, respectively); however, the association with δ(13)C was strongest for models based on RBCs and hair. There were no associations with fasting plasma glucose δ(13)C (R(2) = 0.03). The δ(13)C and δ(15)N values of RBCs, plasma, and hair showed strong, positive correlations; the slopes of these relations did not differ from 1. This study demonstrates that RBC, plasma, and hair isotope ratios predict sugar intake and provides data that will allow comparison of studies using different sample types.

  19. Fast and accurate quantum molecular dynamics of dense plasmas across temperature regimes

    DOE PAGES

    Sjostrom, Travis; Daligault, Jerome

    2014-10-10

    Here, we develop and implement a new quantum molecular dynamics approximation that allows fast and accurate simulations of dense plasmas from cold to hot conditions. The method is based on a carefully designed orbital-free implementation of density functional theory. The results for hydrogen and aluminum are in very good agreement with Kohn-Sham (orbital-based) density functional theory and path integral Monte Carlo calculations for microscopic features such as the electron density as well as the equation of state. The present approach does not scale with temperature and hence extends to higher temperatures than is accessible in the Kohn-Sham method and lowermore » temperatures than is accessible by path integral Monte Carlo calculations, while being significantly less computationally expensive than either of those two methods.« less

  20. Sound produced by a fast parton in the quark-gluon plasma is a "crescendo".

    PubMed

    Neufeld, R B; Müller, B

    2009-07-24

    We calculate the total energy deposited into the medium per unit length by fast partons traversing a quark-gluon plasma. The medium excitation due to collisions is taken to be given by the well-known expression for the collisional drag force. The radiative energy loss of the parton contributes to the energy deposition because each radiated gluon acts as an additional source of collisional energy loss in the medium. We derive a differential equation which governs how the spectrum of radiated gluons is modified when this energy loss is taken into account. This modified spectrum is then used to calculate the additional energy deposition due to the interactions of radiated gluons with the medium. Numerical results are presented for the medium response for the case of two energetic back-to-back partons created in a hard interaction.

  1. Sound Produced by a Fast Parton in the Quark-Gluon Plasma is a ``Crescendo''

    NASA Astrophysics Data System (ADS)

    Neufeld, R. B.; Müller, B.

    2009-07-01

    We calculate the total energy deposited into the medium per unit length by fast partons traversing a quark-gluon plasma. The medium excitation due to collisions is taken to be given by the well-known expression for the collisional drag force. The radiative energy loss of the parton contributes to the energy deposition because each radiated gluon acts as an additional source of collisional energy loss in the medium. We derive a differential equation which governs how the spectrum of radiated gluons is modified when this energy loss is taken into account. This modified spectrum is then used to calculate the additional energy deposition due to the interactions of radiated gluons with the medium. Numerical results are presented for the medium response for the case of two energetic back-to-back partons created in a hard interaction.

  2. Fast differentiation of SIRS and sepsis from blood plasma of ICU patients using Raman spectroscopy.

    PubMed

    Neugebauer, Ute; Trenkmann, Sabine; Bocklitz, Thomas; Schmerler, Diana; Kiehntopf, Michael; Popp, Jürgen

    2014-04-01

    Currently, there is no biomarker that can reliable distinguish between infectious and non-infectious systemic inflammatory response syndrome (SIRS). However, such a biomarker would be of utmost importance for early identification and stratification of patients at risk to initiate timely and appropriate antibiotic treatment. Within this proof of principle study, the high potential of Raman spectroscopy for the fast differentiation of non-infectious SIRS and sepsis is demonstrated. Blood plasma collected from 70 patients from the intensive care unit (31 patients with sepsis and 39 patients classified with SIRS without infection) was analyzed by means of Raman spectroscopy. A PCA-LDA based classification model was trained with Raman spectra from test samples and yielded for sepsis a sensitivity of 1.0 and specificity of 0.82. These results have been confirmed with an independent dataset (prediction accuracy 80%).

  3. Fast and accurate quantum molecular dynamics of dense plasmas across temperature regimes

    SciTech Connect

    Sjostrom, Travis; Daligault, Jerome

    2014-10-10

    Here, we develop and implement a new quantum molecular dynamics approximation that allows fast and accurate simulations of dense plasmas from cold to hot conditions. The method is based on a carefully designed orbital-free implementation of density functional theory. The results for hydrogen and aluminum are in very good agreement with Kohn-Sham (orbital-based) density functional theory and path integral Monte Carlo calculations for microscopic features such as the electron density as well as the equation of state. The present approach does not scale with temperature and hence extends to higher temperatures than is accessible in the Kohn-Sham method and lower temperatures than is accessible by path integral Monte Carlo calculations, while being significantly less computationally expensive than either of those two methods.

  4. Latinas with Elevated Fasting Plasma Glucose: An Analysis Using NHANES 2009–2010 Data

    PubMed Central

    Strauss, Shiela M.; Vega, Marlena; Clayton-Jeter, Helene D.; Deren, Sherry; Rosedale, Mary; Rindskopf, David M.

    2017-01-01

    For Latinas with fasting plasma glucose (FPG) levels in the pre-diabetes and diabetes ranges, early detection can support steps to optimize their health. Data collected in 2009–2010 indicate that 36.7% of Latinas in the U.S. had elevated FPG levels. Latinas with elevated FPG who were unaware of their diabetes status were significantly less likely than non-Hispanic White and non-Hispanic Black women to have seen a health care provider in the past year (75.8%, 92.9%, and 90.2%, respectively; p = .018). With almost 1 million Latinas in the U.S. with elevated FPG unaware of their diabetes risk, and less likely than other at-risk women to see health care providers, there is an urgent need to establish alternate sites of opportunity for their diabetes screening. PMID:24865436

  5. ISEE-1 and ISEE-2 fast plasma experiment and the ISEE-1 solar wind experiment

    NASA Technical Reports Server (NTRS)

    Bame, S. J.; Asbridge, J. R.; Felthauser, H. E.; Glore, J. P.; Paschmann, G.; Hemmerich, P.; Lehmann, K.; Rosenbauer, H.

    1978-01-01

    Identical fast plasma experiment (FPE) systems were placed on the ISEE-1 and ISEE-2 spacecraft. The FPE consists of three high efficiency 90 deg spherical section electrostatic analyzers using large secondary emitters and discrete dynode multipliers to detect analyzed particles. Two of them, viewing in opposite directions, produce complete 2D velocity distribution measurements of both protons and electrons every spacecraft revolution. A third FPE analyzer with a divided emitter measures 3D distributions at a slower rate. ISEE-1 also carries a solar-wind experiment (SWE) to measure solar-wind ions with high resolution. The SWE is composed of two 150 deg spherical section analyzers using the same set of plates. The two acceptance fans are tilted with respect to each other so that 3D characteristics of the ion distributions can be derived.

  6. Time dependence of fast electron beam divergence in ultraintense laser-plasma interactions.

    PubMed

    Akli, K U; Storm, M J; McMahon, M; Jiang, S; Ovchinnikov, V; Schumacher, D W; Freeman, R R; Dyer, G; Ditmire, T

    2012-08-01

    We report on the measurement and computer simulation of the divergence of fast electrons generated in an ultraintense laser-plasma interaction (LPI) and the subsequent propagation in a nonrefluxing target. We show that, at Iλ(2) of 10(20) Wcm(-2)μm(2), the time-integrated electron beam full divergence angle is (60±5)°. However, our time-resolved 2D particle-in-cell simulations show the initial beam divergence to be much smaller (≤30°). Our simulations show the divergence to monotonically increase with time, reaching a final value of (68±7)° after the passage of the laser pulse, consistent with the experimental time-integrated measurements. By revealing the time-dependent nature of the LPI, we find that a substantial fraction of the laser energy (~7%) is transported up to 100 μm with a divergence of 32°.

  7. The efficiency of fast wave current drive for a weakly relativistic plasma

    NASA Astrophysics Data System (ADS)

    Chiu, S. C.; Lin-Liu, Y. R.; Karney, C. F. F.

    1994-10-01

    Current drive by fast waves (FWCD) is an important candidate for steady-state operation of tokamaks. Major experiments using this scheme are being carried out on DIII-D. There has been considerable study of the theoretical efficiency of FWCD. In Refs. 4 and 5, the nonrelativistic efficiency of FWCD at arbitrary frequencies was studied. For DIII-D parameters, the results can be considerably different from the Landau and Alfvén limits. At the high temperatures of reactors and DIII-D upgrade, relativistic effects become important. In this paper, the relativistic FWCD efficiency for arbitrary frequencies is studied. Assuming that the plasma is weakly relativistic, i.e., Te/mc2 is small, an analytic expression for FWCD is obtained for high resonant energies (uph/uTe≫1). Comparisons with the results from a numerical code ADJ and the nonrelativistic results shall be made and analytical fits in the whole range of velocities shall be presented.

  8. Method for determining fast-alpha-particle confinement in tokamak plasmas using resonant nuclear reactors

    SciTech Connect

    Cecil, F.E.; Zweben, S.J.; Medley, S.S.

    1986-03-01

    The resonant nuclear reactions D(..cap alpha..,..gamma..)/sup 6/Li, /sup 6/Li(..cap alpha..,..gamma..)/sup 10/B, and /sup 7/Li(..cap alpha..,..gamma..)/sup 11/B are examined as diagnostics of fast-alpha-particle confinement in tokamak plasmas. Gamma rays from these resonant reactions with energies from 2.1 MeV to 9.2 MeV may be used to infer the alpha-particle population between energies of 0.4 MeV and 2.6 MeV. The ratio of these alpha-burnup reactions to the reactions T(D,..gamma..)/sup 5/He and /sup 3/He(D,..gamma..)/sup 5/Li provides a technique for the measurement of alpha confinement.

  9. The Geometric Factor of Electrostatic Plasma Analyzers: A Case Study from the Fast Plasma Investigation for the Magnetospheric Multiscale mission

    NASA Technical Reports Server (NTRS)

    Collinson, Glyn A.; Dorelli, John Charles; Avanov, Leon A.; Lewis, Gethyn R.; Moore, Thomas E.; Pollock, Craig; Kataria, Dhiren O.; Bedington, Robert; Arridge, Chris S.; Chornay, Dennis J.; Gliese,Ulrik; Mariano, Al.; Barrie, Alexander C; Tucker, Corey; Owen, Christopher J.; Walsh, Andrew P.; Shappirio, Mark D.; Adrian, Mark L.

    2012-01-01

    We report our findings comparing the geometric factor (GF) as determined from simulations and laboratory measurements of the new Dual Electron Spectrometer (DES) being developed at NASA Goddard Space Flight Center as part of the Fast Plasma Investigation on NASA's Magnetospheric Multiscale mission. Particle simulations are increasingly playing an essential role in the design and calibration of electrostatic analyzers, facilitating the identification and mitigation of the many sources of systematic error present in laboratory calibration. While equations for laboratory measurement of the Geometric Factpr (GF) have been described in the literature, these are not directly applicable to simulation since the two are carried out under substantially different assumptions and conditions, making direct comparison very challenging. Starting from first principles, we derive generalized expressions for the determination of the GF in simulation and laboratory, and discuss how we have estimated errors in both cases. Finally, we apply these equations to the new DES instrument and show that the results agree within errors. Thus we show that the techniques presented here will produce consistent results between laboratory and simulation, and present the first description of the performance of the new DES instrument in the literature.

  10. Dual Ion Spectrometers and Their Calibration for the Fast Plasma Investigation on NASA's Magnetospheric Multiscale Mission

    NASA Technical Reports Server (NTRS)

    Coffey, V. N.; Chandler, M. O.

    2017-01-01

    The scientific target of NASA's Magnetospheric Multiscale (MMS) mission is to study the fundamentally important phenomenon of magnetic reconnection. Theoretical models of this process predict a small size, on the order of hundred kilometers, for the ion diffusion region where ions are demagnetized at the dayside magnetopause. This region may typically sweep over the spacecraft at relatively high speeds of 50 km/s, requiring the fast plasma investigation (FPI) instrument suite to have an extremely high time resolution for measurements of the 3D particle distribution functions. As part of the FPI on MMS, the 16 dual ion spectrometers (DIS) will provide fast (150 ms) 3D ion velocity distributions, from 10 to 30,000 eV/q, by combining the measurements from four dual spectrometers on each of four MMS spacecraft. For any multispacecraft mission, the response uniformity among the spectrometer set assumes an enhanced importance. Due to these demanding instrument requirements and the effort of calibrating more than 32 sensors (16 × 2) within a tight schedule, a highly systematic and precise calibration was required for measurement repeatability. To illustrate how this challenge was met, a brief overview of the FPI DIS was presented with a detailed discussion of the calibration method of approach and implementation. Finally, a discussion of DIS performance results, their unit-to-unit variation, and the lessons learned from this calibration effort are presented.

  11. Understanding ion cyclotron harmonic fast wave heating losses in the scrape off layer of tokamak plasmas

    SciTech Connect

    Bertelli, N; Jaeger, E F; Hosea, J C; Phillips, C K; Berry, L; Bonoli, P T; Gerhardt, S P; Green, D; LeBlanc, B; Perkins, R J; Ryan, P M; Taylor, G; Valeo, E J; Wilso, J R; Wright, J C

    2014-07-01

    Fast waves at harmonics of the ion cyclotron frequency, which have been used successfully on National Spherical Torus Experiment (NSTX), will also play an important role in ITER and are a promising candidate for the Fusion Nuclear Science Facility (FNSF) designs based on spherical torus (ST). Experimental studies of high harmonic fast waves (HHFW) heating on the NSTX have demonstrated that substantial HHFW power loss occurs along the open field lines in the scrape-off layer (SOL), but the mechanism behind the loss is not yet understood. The full wave RF code AORSA, in which the edge plasma beyond the last closed flux surface (LCFS) is included in the solution domain, is applied to specific NSTX discharges in order to predict the effects and possible causes of this power loss. In the studies discussed here, a collisional damping parameter has been implemented in AORSA as a proxy to represent the real, and most likely nonlinear, damping processes. A prediction for the NSTX Upgrade (NSTX-U) experiment, that will begin operation next year, is also presented, indicating a favorable condition for the experiment due to a wider evanescent region in edge density.*Research supported by the U.S. DOE under Contract No. DE-AC02-09CH11466 with Princeton University.

  12. Fast synthesis and consolidation of porous FeAl by pressureless Spark Plasma Sintering

    NASA Astrophysics Data System (ADS)

    Dudina, D. V.; Brester, A. E.; Anisimov, A. G.; Bokhonov, B. B.; Legan, M. A.; Novoselov, A. N.; Skovorodin, I. N.; Uvarov, N. F.

    2017-07-01

    We report one-step fast synthesis and consolidation of iron aluminide FeAl of high open porosity by pressureless reactive Spark Plasma Sintering (SPS). The starting material of the Fe-40at.%Al composition was a mixture of an iron powder with an average particle diameter of 4 μm and an aluminum powder with an average particle diameter of 6 μm. The rationale behind the choice of the SPS as a processing technique and fine and comparable sizes of the two reactants for the synthesis of high-open porosity FeAl was realization of fast full chemical conversion of Fe and Al into single-phase FeAl reducing the time available for the compact shrinkage. According to the XRD phase analysis, single-phase FeAl compacts formed after SPS at 800 and 900°C. These compacts had open porosities of 41 and 46%, respectively. The transverse rupture strength of the compacts sintered at 700-900°C was found to change little with the sintering temperature in the selected range.

  13. Investigation of interaction between fast ions and tearing modes in MST plasmas using full orbit tracing

    NASA Astrophysics Data System (ADS)

    Kim, Jungha; Anderson, Jay; Capecchi, William; Bonofiglo, Phillip; Sears, Stephanie; Tsidulko, Yuri

    2015-11-01

    Under proper conditions, global reconnection events generate an anisotropic runaway ion distribution in MST plasmas. Full orbit tracing with time-dependent fluctuating fields, calculated by the nonlinear resistive MHD code DEBS, is used to inform a refined model of ion heating to explain this phenomenon, where tearing modes and ions interact on two distinct scales. There is anisotropic heating of thermal ions (T⊥>T∥), likely through a stochastic heating mechanism that requires high diffusivity and a tearing mode induced radial electric field with correlation length of a few cm. This process does not, however, continuously energize ions into the runaway regime. At sufficient energy, the ion guiding center deviates from the background magnetic field, which reduces the effective diffusivity to classical levels even in a stochastic magnetic field. These ``fast'' ions are accelerated by a parallel electric field (length scale of meters) induced by the equilibrium change accompanying tearing modes. This process relies on multiple global tearing modes; here we focus on a single tearing mode. This is compared to an experimental state where a transition to a single, dominant tearing mode is observed to accelerate fast ions and alter their confinement properties. Work supported by US DOE.

  14. Fast XUV 16 × 16 Array Hybrid Module for Plasma Imaging Applications

    NASA Astrophysics Data System (ADS)

    Alekseyev, Andrey G.; Belov, Alexandr M.; Zabrodsky, Vladimir V.; Sukhanov, Vladislav L.; Sorokin, Andrey A.; Peterson, Byron J.

    A hybrid matrix array detector is developed for ultra-fast plasma imaging applications with the use of XUV Si photodiodes (SPD diodes) manufactured according to Ioffe Institute original technology. A basic 16 × 16 hybrid module is comprised of eight stacked sub-modules with 2 × 16 linear SPD diode arrays combined with a circuit board with a 32-channel preamplifier and four 8-channel fast multiplexers. Array front size is 31 × 31 mm2 with ˜25 % sensitive area. The module has a “zero-edge” design providing an option of stacking into the larger arrays, if necessary. The data acquisition system (DAS) consists of eight 4-channel synchronous 12-bit ADC modules with 40 MS/s upper sampling rate, thus providing less than 1 μs minimum time for the complete read-out of the array. Each channel has a 64 MB on-board memory limiting the duration of the acquired period to 0.8 sec at the maximum sampling rate. A common TCP/IP Ethernet protocol is used for the data transmission into the main PC operating as a DAS control console, data preview and storage computer.

  15. Nonlinear effects associated with fast magnetosonic waves and turbulent magnetic amplification in laboratory and astrophysical plasmas

    NASA Astrophysics Data System (ADS)

    Tiwary, PremPyari; Sharma, Swati; Sharma, Prachi; Singh, Ram Kishor; Uma, R.; Sharma, R. P.

    2016-12-01

    This paper presents the spatio-temporal evolution of magnetic field due to the nonlinear coupling between fast magnetosonic wave (FMSW) and low frequency slow Alfvén wave (SAW). The dynamical equations of finite frequency FMSW and SAW in the presence of ponderomotive force of FMSW (pump wave) has been presented. Numerical simulation has been carried out for the nonlinear coupled equations of finite frequency FMSW and SAW. A systematic scan of the nonlinear behavior/evolution of the pump FMSW has been done for one of the set of parameters chosen in this paper, using the coupled dynamical equations. Filamentation of fast magnetosonic wave has been considered to be responsible for the magnetic turbulence during the laser plasma interaction. The results show that the formation and growth of localized structures depend on the background magnetic field but the order of amplification does not get affected by the magnitude of the background magnetic field. In this paper, we have shown the relevance of our model for two different parameters used in laboratory and astrophysical phenomenon. We have used one set of parameters pertaining to experimental observations in the study of fast ignition of laser fusion and hence studied the turbulent structures in stellar environment. The other set corresponds to the study of magnetic field amplification in the clumpy medium surrounding the supernova remnant Cassiopeia A. The results indicate considerable randomness in the spatial structure of the magnetic field profile in both the cases and gives a sufficient indication of turbulence. The turbulent spectra have been studied and the break point has been found around k which is consistent with the observations in both the cases. The nonlinear wave-wave interaction presented in this paper may be important in understanding the turbulence in the laboratory as well as the astrophysical phenomenon.

  16. Serum Fibroblast Growth Factor 19 Levels Are Decreased in Chinese Subjects With Impaired Fasting Glucose and Inversely Associated With Fasting Plasma Glucose Levels

    PubMed Central

    Fang, Qichen; Li, Huating; Song, Qianqian; Yang, Wenjing; Hou, Xuhong; Ma, Xiaojing; Lu, Junxi; Xu, Aimin; Jia, Weiping

    2013-01-01

    OBJECTIVE Fibroblast growth factor 19 (FGF19), a hormone secreted from the small intestine, has recently been shown to stimulate glycogen synthesis and inhibit gluconeogenesis through insulin-independent pathways. This study investigated the change of FGF19 in prediabetes and newly diagnosed type 2 diabetes mellitus (T2DM) and explored the association of serum FGF19 levels with parameters of glucose metabolism in Chinese subjects. RESEARCH DESIGN AND METHODS Fasting serum FGF19 levels were determined by ELISA in 81 normal glucose tolerance (NGT), 91 impaired fasting glucose (IFG), 93 impaired glucose tolerance (IGT), and 104 newly diagnosed T2DM subjects, and their association with parameters of glucose metabolism was studied. An ordinal logistic regression analysis was performed in subjects with NGT, IFG, and T2DM. Serum FGF19 levels at 2 h after a 75-g oral glucose tolerance test in the different glucose tolerance categories were studied in a subgroup. RESULTS Fasting serum FGF19 levels in subjects with IFG (210 pg/mL [142–327]) (median [interquartile range]) and T2DM (196 pg/mL [137–280]) were significantly lower than those in NGT subjects (289 pg/mL [224–393]) (both P < 0.001). However, no significant difference in fasting FGF19 levels was observed between IGT (246 pg/mL [138–379]) and NGT subjects. Fasting serum FGF19 levels were negatively associated with fasting plasma glucose and independently associated with the deterioration of glucometabolic status from NGT to IFG and T2DM. CONCLUSIONS Fasting serum FGF19 levels were decreased in Chinese subjects with IFG and inversely associated with fasting glucose levels. PMID:23628619

  17. Impact of fasting and postprandial state on plasma carnitine concentrations during aerobic exercise in type 2 diabetes.

    PubMed

    Ferland, A; Broderick, T L; Nadeau, A; Simard, S; Martin, J; Poirier, P

    2007-09-01

    The effects of metabolic states of fasting and post-absorption on plasma concentrations of free carnitine (FC), acylcarnitine (AC) and total carnitine (TC) were compared during submaximal exercise in subjects with type 2 diabetes mellitus. Ten sedentary men (54+/-5 years) treated with oral hypoglycaemic agents were tested on two separate occasions: following an overnight fast and 2 h after a 395-kcal standardised breakfast. Exercise was performed at 60% of [Formula: see text]O(2peak) on a cycle ergometer for 60 min. Blood samples were drawn at rest for baseline values and following 60 min of exercise and 30 min of recovery. Our results show that: (1) baseline levels of TC, FC and AC were similar in fasted and postprandial groups, (2) TC and AC levels were increased during exercise in the fasted group only, (3) FC levels were decreased during exercise in both fasted and postprandial state and (4) the AC/FC ratio increased during exercise in the fasted group. Our results indicate that the metabolic state of the diabetic patient is associated with a different plasma carnitine status. These patterns may reflect differences in energy metabolism associated with fasting and postprandial hyperglycaemia.

  18. Fast valve and nozzle for gas-puff operation of dense plasma focus

    NASA Astrophysics Data System (ADS)

    Milanese, María M.; Pouzo, Jorge O.; Cortázar, Osvaldo D.; Moroso, Roberto L.

    2006-03-01

    A simple and reliable valve and nozzle system for a very fast injection of gas has been designed and constructed for its use in gas-puff mode of dense plasma focus experiments. It delivers a very quick rise time: 55μs. The pressure measured in our setup at a distance of 15 mm from the nozzle output is about 0.285 mbar, with a plenum pressure of 3 bars (absolute). The time between the valve aperture and pressure front arrival is 360μs. This result comes up as an average of about a hundred measurements. The energy input is 95 J (270 V on a 3000μF capacitor bank). The typical dimensions of the valve are 52 mm in diameter and 80 mm in length. The entire volume of the valve is, then, very small. The relative low pressure and voltage operation are significant advantages of this development. The performance of the valve satisfactorily fulfills the objectives of gas-puff plasma focus operation.

  19. Partial conservation of the sn-2 position of dietary triglycerides in fasting plasma lipids in humans.

    PubMed

    Zock, P L; Gerritsen, J; Katan, M B

    1996-02-01

    The authors investigated the effect of the position of fatty acids within dietary triglycerides on the composition of plasma lipids. Sixty volunteers consumed two diets of equal fatty acid compositions for 3 weeks each. In the palm oil diet 82% of palmitic acid was attached to the sn-1 and sn-3, and 18% to the sn-2 position of glycerol. In the diet rich in a palm oil analogue, Betapol, these figures were 35% and 65% respectively. Oleic and linoleic acid in palm oil were mainly in the sn-2 position, and in Betapol mainly in the sn-1 and sn-3 position. The proportion of palmitic acid in the 2 position of fasting plasma triglycerides was 10·2 g 100 g-1 on palm oil and 12·3 on Betapol; that of oleic acid was 46·dot 9 vs. 43·6 (P < 0·0001). Overall oleic acid content of triglycerides was 1·4 g 100 g-1 lower on Betapol than on palm oil (P = 0·002). Betapol increased palmitic and palmitoleic acid in cholesteryl esters by 1 g 100 g-1 (P < 0·0001) at the expense of oleic and linoleic acid. The positional configuration of dietary fatty acids has small but consistent effects on lipid metabolism that persist beyond fat absorption and chylomicron clearance.

  20. Differential expression of cholesteryl ester transfer protein in the liver and plasma of fasted and fed transgenic mice.

    PubMed

    MacLean, P S; Vadlamudi, S; Hao, E; Barakat, H A

    2000-06-01

    Because cholesteryl ester transfer protein (CETP) is considered a potential target in the treatment of atherosclerosis, several reports have focused on the regulation of this enzyme, and there is evidence that insulin may be a regulatory factor. The present study examines the differential expression of the human CETP gene between physiologic conditions that are accompanied by low (fasted) and high (fed) insulin levels. CETP expression was examined in plasma and tissues of transgenic mice expressing the human CETP minigene after 12 hours of fasting (n = 20) or ad libitum feeding (n = 20) with normal mouse chow. Plasma cholesteryl ester transfer activity (CETA) was 20% higher in fed than in fasted mice, reflecting higher levels of CETP (P < 0.05). This observation was accompanied by higher liver mRNA in fed mice (100%, P < 0.05), as determined by ribonuclease protection assays, as well as by higher CETA (23%, P < 0.05) and CETP mass (29%, P < 0.05) in the particulate fraction of liver homogenates. These parameters of liver CETP expression correlated well with each other, as well as with plasma CETA. CETP in the liver particulate fraction was found as a doublet (approximately 70 and 65 kDa), which resolved to a single band (approximately 60 kDa) upon deglycosylation. No differences in CETP expression were observed in pooled adipose tissue samples from fed and fasted mice. Insulin and glucose were not related to any plasma or tissue parameter of CETP expression. In summary, the concerted, differential expression of CETP in the liver of fed and fasted transgenic mice appears to contribute to higher plasma CETP levels in fed mice, but the precise role of insulin and glucose in regulating CETP expression under fasted and fed conditions needs to be defined.

  1. Ethnicity modifies the relation between fasting plasma glucose and HbA1c in Indians, Malays and Chinese.

    PubMed

    Venkataraman, K; Kao, S L; Thai, A C; Salim, A; Lee, J J M; Heng, D; Tai, E S; Khoo, E Y H

    2012-07-01

    To study whether HbA(1c) , and its relationship with fasting plasma glucose, was significantly different among Chinese, Malays and Indians in Singapore. A sample of 3895 individuals without known diabetes underwent detailed interview and health examination, including anthropometric and biochemical evaluation, between 2004 and 2007. Pearson's correlation, analysis of variance and multiple linear regression analyses were used to examine the influence of ethnicity on HbA(1c) . As fasting plasma glucose increased, HbA(1c) increased more in Malays and Indians compared with Chinese after adjustment for age, gender, waist circumference, serum cholesterol, serum triglyceride and homeostasis model assessment of insulin resistance (P-interaction < 0.001). This translates to an HbA(1c) difference of 1.1 mmol/mol (0.1%, Indians vs. Chinese), and 0.9 mmol/mol (0.08%, Malays vs. Chinese) at fasting plasma glucose 5.6 mmol/l (the American Diabetes Association criterion for impaired fasting glycaemia); and 2.1 mmol/mol (0.19%, Indians vs. Chinese) and 2.6 mmol/mol (0.24%, Malays vs. Chinese) at fasting plasma glucose 7.0 mmol/l, the diagnostic criterion for diabetes mellitus. Using HbA(1c) in place of fasting plasma glucose will reclassify different proportions of the population in different ethnic groups. This may have implications in interpretation of HbA(1c) results across ethnic groups and the use of HbA(1c) for diagnosing diabetes mellitus. © 2012 The Authors. Diabetic Medicine © 2012 Diabetes UK.

  2. Device and method for relativistic electron beam heating of a high-density plasma to drive fast liners

    DOEpatents

    Thode, Lester E.

    1981-01-01

    A device and method for relativistic electron beam heating of a high-density plasma in a small localized region. A relativistic electron beam generator or accelerator produces a high-voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low-density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high-density target plasma which typically comprises DT, DD, hydrogen boron or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target gas is ionized prior to application of the electron beam by means of a laser or other preionization source to form a plasma. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high-density target plasma causing the relativistic electron beam to efficiently deposit its energy and momentum into a small localized region of the high-density plasma target. Fast liners disposed in the high-density target plasma are explosively or ablatively driven to implosion by a heated annular plasma surrounding the fast liner which is generated by an annular relativistic electron beam. An azimuthal magnetic field produced by axial current flow in the annular plasma, causes the energy in the heated annular plasma to converge on the fast liner.

  3. Triglycerides produced in the livers of fasting rabbits are predominantly stored as opposed to secreted into the plasma

    PubMed Central

    Tuvdendorj, Demidmaa; Zhang, Xiao-jun; Chinkes, David L.; Wang, Lijian; Wu, Zhanpin; Rodriguez, Noe A.; Herndon, David N.; Wolfe, Robert R.

    2015-01-01

    Objective The liver plays a central role in regulating fat metabolism; however, it is not clear how the liver distributes the synthesized triglycerides (TGs) to storage and to the plasma. Materials and Methods We have measured the relative distribution of TGs produced in the liver to storage and the plasma by means of U-13C16-palmitate infusion in anesthetized rabbits after an overnight fast. Results The fractional synthesis rates of TGs stored in the liver and secreted into the plasma were not significantly different (Stored vs. Secreted: 31.9 ± 0.8 vs. 27.7 ± 2.6 %•h−1, p > 0.05. However, the absolute synthesis rates of hepatic stored and secreted TGs were 543 ± 158 and 27 ± 7 nmol·kg−1·min−1 respectively, indicating that in fasting rabbits the TGs produced in the liver were predominately stored (92±3%) rather than secreted (8±3%) into the plasma. This large difference was mainly due to the larger pool size of the hepatic TGs which was 21±9-fold that of plasma TGs. Plasma free fatty acids (FFAs) contributed 47±1% of the FA precursor for hepatic TG synthesis, and the remaining 53±1% was derived from hepatic lipid breakdown and possibly plasma TGs depending on the activity of hepatic lipase. Plasma palmitate concentration significantly correlated with hepatic palmitoyl-CoA and TG synthesis. Conclusion In rabbits, after an overnight fast, the absolute synthesis rate of hepatic stored TGs was significantly higher than that of secreted due to the larger pool size of hepatic TGs. The net synthesis rate of TG was approximately half the absolute rate. Plasma FFA is a major determinant of hepatic TG synthesis, and therefore hepatic TG storage. PMID:25682063

  4. Acute fasting in heifers as a model for assessing the relationship between plasma and follicular fluid NEFA concentrations.

    PubMed

    Jorritsma, R; de Groot, M W; Vos, P L A M; Kruip, T A M; Wensing, Th; Noordhuizen, J P T M

    2003-06-01

    It is known from epidemiological studies that negative energy balance in early lactating dairy cows is related to a depression in reproductive performance. Elevated plasma concentrations of non-esterified fatty acids (NEFA) are a typical metabolic characteristic of these animals and are proposed as the possible link. The suggestion is that NEFA might have a direct effect on the ovary, by affecting development of the oocyte or the granulosa cells. However, no data is available concerning the relationship between the concentration of NEFA in follicular fluid and plasma. Therefore, a cross-over study with 10 heifers around 15 months of age was conducted to analyze this relationship and examine the suggested effects of the negative energy balance on follicular growth. Investigation of these effects was performed on fasted heifers. The experimental treatment consisted of feeding hay with a subsequent period of fasting, to induce elevated plasma NEFA concentrations. Sampling of follicular fluid was performed using transvaginal aspiration of follicles, which were standardized using a synchronization protocol. In addition, concentrations of glucose, insulin, NEFA, and estradiol were measured in plasma. Follicular estradiol and progesterone concentrations were also measured to assess the quality of the dominant follicle. Fasting resulted in significantly lower plasma glucose (P=0.0006) and plasma insulin (P<0.0001) concentrations, higher plasma estradiol (P=0.008) and higher NEFA (P<0.001) concentrations, and smaller follicles (P=0.04) with lower estradiol:progesterone (E/P) ratios (P=0.05). Concentrations of NEFA in follicular fluid and plasma were closely related. Given this close relationship, we concluded that the presence of high plasma NEFA concentrations might link energy metabolism in early lactation with fertility.

  5. Lensing of Fast Radio Bursts by Plasma Structures in Host Galaxies

    NASA Astrophysics Data System (ADS)

    Cordes, J. M.; Wasserman, I.; Hessels, J. W. T.; Lazio, T. J. W.; Chatterjee, S.; Wharton, R. S.

    2017-06-01

    The amplitudes of fast radio bursts (FRBs) can be strongly modulated by plasma lenses in their host galaxies, including that of the repeating FRB 121102 at ˜1 Gpc luminosity distance. Caustics require the lens’ dispersion measure depth ({{DM}}{\\ell }), scale size (a), and distance from the source ({d}{sl}) to satisfy {{DM}}{\\ell }{d}{sl}/{a}2≳ 0.65 {{pc}}2 {{au}}-2 {{cm}}-3. Caustics produce strong magnifications (≲ {10}2) on short timescales (≲ hours to days) that appear as narrow spectral peaks (0.1-1 GHz). They also suppress the flux density in longer-duration (˜months) troughs. Multiply imaged bursts will arrive differentially by < 1 μ {{s}} to tens of ms with different apparent dispersion measures, δ {DM}˜ 1 pc cm-3. When differing by less than the burst width, interference effects in dynamic spectra will be seen. Larger arrival time perturbations may mask any underlying periodicity with period ≲ 1 {{s}}. Strong lensing requires sources smaller than {({Fresnel}{scale})}2/a, which includes compact objects such as neutron star magnetospheres but excludes active galactic nuclei. We discuss constraints on densities, magnetic fields, and locations of plasma lenses related to the conditions needed for lensing to occur. Much of the phenomenology of the repeating FRB source FRB 121102 can be accounted for in this picture, which can be tested by obtaining wideband spectra of bursts (from < 1 to 10 GHz and possibly higher) that will also help characterize the plasma environment near FRB sources. A rich variety of phenomena is expected from an ensemble of lenses near an FRB source.

  6. Plasma Dynamics and VUV Emission in a Fast Hollow Cathode Capillary Discharge

    NASA Astrophysics Data System (ADS)

    Soto, Leopoldo; Esaulov, Andrey; Silva, Patricio; Sylvester, Gustavo; Moreno, José; Zambra, Marcelo; Nazarenko, Andrey

    2000-10-01

    Following the world tendency to study the physical mechanisms to obtain laser emission in the VUV to soft X-ray region in table-top device, a fast capillary discharge has been constructed at Comisión Chilena de Energía Nuclear, CCHEN. The device is identical to designed by P. Choi and M. Favre, included an electron beam from the hollow cathode region to provide ionization on the axis (1). The discharge operates in Argon with a cathode pressure of 100-500 mtorr. The system works with differential vacuum, thus the anode pressure is around five times less than the cathode pressure. The radius of capillary is 0.4 mm and the length is 2.5 cm. For an applied voltage of 10 kV a peak current of 5 kA with a rise time of 4.8 ns is obtained (10^12 A/s). MHD simulations in order to study the plasma dynamics an temperature evolution were performed (2). A final radius of 100-200 microns is expected at 8 ns, 2 ns after the peak current with a electron density of 2 x 10^18 cm-3. An electron and ion temperature of 80 and 40 eV respectively are predicted. In addition to usual electrical diagnostics, time-space resolution pinhole images (multipinhole camera with a multichannel plate, four frames, one frame every 4 ns) and time resolved spectra in the region of 10 to 100 nm were performed. Dynamics of plasma compresion was studied from time resolved pinhole images. Detected spectra show that plasma consists of argon ions with ionization potential from ArVI to ArX. This work has been funded by FONDECYT grant 1980187 and a Presidential Chair in Science granted by Chilean government. Authors are thankful to K. Koshelev and P. Antsiferov (ISAN, Troitsk) for fruitful discussions and comments. 1.- P. Choi and M. Favre, Rev. Sci. Instrum. 69, 3118, (1998) 2.- A. Esaulov, P. Sasorov, L. Soto, M. Zambra and J. Sakai, ``Fast Hollow Cathode Capillary Discharge. MHD Simulation''. Submitted for publication.

  7. Letter report seismic shutdown system failure mode and effect analysis

    SciTech Connect

    KECK, R.D.

    1999-09-01

    The Supply Ventilation System Seismic Shutdown ensures that the 234-52 building supply fans, the dry air process fans and vertical development calciner are shutdown following a seismic event. This evaluates the failure modes and determines the effects of the failure modes.

  8. 46 CFR 111.33-7 - Alarms and shutdowns.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Alarms and shutdowns. 111.33-7 Section 111.33-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Power Semiconductor Rectifier Systems § 111.33-7 Alarms and shutdowns. Each power...

  9. 46 CFR 111.33-7 - Alarms and shutdowns.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Alarms and shutdowns. 111.33-7 Section 111.33-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Power Semiconductor Rectifier Systems § 111.33-7 Alarms and shutdowns. Each power...

  10. 46 CFR 111.33-7 - Alarms and shutdowns.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Alarms and shutdowns. 111.33-7 Section 111.33-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Power Semiconductor Rectifier Systems § 111.33-7 Alarms and shutdowns. Each power...

  11. 46 CFR 111.33-7 - Alarms and shutdowns.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Alarms and shutdowns. 111.33-7 Section 111.33-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Power Semiconductor Rectifier Systems § 111.33-7 Alarms and shutdowns. Each power...

  12. 30 CFR 250.603 - Emergency shutdown system.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ....603 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT OF... Well-Workover Operations § 250.603 Emergency shutdown system. When well-workover operations are conducted on a well with the tree removed, an emergency shutdown system (ESD) manually controlled...

  13. 46 CFR 111.33-7 - Alarms and shutdowns.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Alarms and shutdowns. 111.33-7 Section 111.33-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Power Semiconductor Rectifier Systems § 111.33-7 Alarms and shutdowns. Each power semiconductor...

  14. Nuclear reactor shutdown control rod assembly

    DOEpatents

    Bilibin, Konstantin

    1988-01-01

    A temperature responsive, self-actuated nuclear reactor shutdown control rod assembly 10. The upper end 18 of a lower drive line 17 fits within the lower end of an upper drive line 12. The lower end (not shown) of the lower drive line 17 is connected to a neutron absorber. During normal temperature conditions the lower drive line 17 is supported by detent means 22,26. When an overtemperature condition occurs thermal actuation means 34 urges ring 26 upwardly sufficiently to allow balls 22 to move radially outwardly thereby allowing lower drive line 17 to move downwardly toward the core of the nuclear reactor resulting in automatic reduction of the reactor powder.

  15. Self-actuating reactor shutdown system

    DOEpatents

    Barrus, Donald M.; Brummond, Willian A; Peterson, Leslie F.

    1988-01-01

    A control system for the automatic or self-actuated shutdown or "scram" of a nuclear reactor. The system is capable of initiating scram insertion by a signal from the plant protection system or by independent action directly sensing reactor conditions of low-flow or over-power. Self-actuation due to a loss of reactor coolant flow results from a decrease of pressure differential between the upper and lower ends of an absorber element. When the force due to this differential falls below the weight of the element, the element will fall by gravitational force to scram the reactor. Self-actuation due to high neutron flux is accomplished via a valve controlled by an electromagnet and a thermionic diode. In a reactor over-power, the diode will be heated to a change of state causing the electromagnet to be shorted thereby actuating the valve which provides the changed flow and pressure conditions required for scramming the absorber element.

  16. Magnetic latch trigger for inherent shutdown assembly

    DOEpatents

    Sowa, Edmund S.

    1976-01-01

    An inherent shutdown assembly for a nuclear reactor is provided. A neutron absorber is held ready to be inserted into the reactor core by a magnetic latch. The latch includes a magnet whose lines of force are linked by a yoke of material whose Curie point is at the critical temperature of the reactor at which the neutron absorber is to be inserted into the reactor core. The yoke is in contact with the core coolant or fissionable material so that when the coolant or the fissionable material increase in temperature above the Curie point the yoke loses its magnetic susceptibility and the magnetic link is broken, thereby causing the absorber to be released into the reactor core.

  17. The Shutdown Dissociation Scale (Shut-D)

    PubMed Central

    Schalinski, Inga; Schauer, Maggie; Elbert, Thomas

    2015-01-01

    The evolutionary model of the defense cascade by Schauer and Elbert (2010) provides a theoretical frame for a short interview to assess problems underlying and leading to the dissociative subtype of posttraumatic stress disorder. Based on known characteristics of the defense stages “fright,” “flag,” and “faint,” we designed a structured interview to assess the vulnerability for the respective types of dissociation. Most of the scales that assess dissociative phenomena are designed as self-report questionnaires. Their items are usually selected based on more heuristic considerations rather than a theoretical model and thus include anything from minor dissociative experiences to major pathological dissociation. The shutdown dissociation scale (Shut-D) was applied in several studies in patients with a history of multiple traumatic events and different disorders that have been shown previously to be prone to symptoms of dissociation. The goal of the present investigation was to obtain psychometric characteristics of the Shut-D (including factor structure, internal consistency, retest reliability, predictive, convergent and criterion-related concurrent validity). A total population of 225 patients and 68 healthy controls were accessed. Shut-D appears to have sufficient internal reliability, excellent retest reliability, high convergent validity, and satisfactory predictive validity, while the summed score of the scale reliably separates patients with exposure to trauma (in different diagnostic groups) from healthy controls. The Shut-D is a brief structured interview for assessing the vulnerability to dissociate as a consequence of exposure to traumatic stressors. The scale demonstrates high-quality psychometric properties and may be useful for researchers and clinicians in assessing shutdown dissociation as well as in predicting the risk of dissociative responding. PMID:25976478

  18. Development of a radio-frequency ion beam source for fast-ion studies on the large plasma device.

    PubMed

    Tripathi, S K P; Pribyl, P; Gekelman, W

    2011-09-01

    A helium ion beam source (23 kV/2.0 A) has been constructed for studying fast-ion physics in the cylindrical magnetized plasma of the large plasma device (LAPD). An inductive RF source produces a 10(19) m(-3) density plasma in a ceramic dome. A multi-aperture, rectangular (8 cm × 8 cm) three-grid system extracts the ion beam from the RF plasma. The ion beam is injected at a variety of pitch angles with Alfvénic speeds in the LAPD. The beam current is intense enough to excite magnetic perturbations in the ambient plasma. Measurements of the ion beam profile were made to achieve an optimum beam performance and a reliable source operation was demonstrated on the LAPD. © 2011 American Institute of Physics

  19. Determination of collision rates relevant to Weibel-like instability growth rates in classical and non-classical plasmas encountered in fast-ignition experiments

    SciTech Connect

    Hill, J M; Key, M H

    2004-10-18

    Analytical simulations of fast-electron currents induced by high-density laser-plasma interactions require estimation of various plasma and beam parameters, including temperatures, densities, and collision rates. This note describes a technique used to estimate or calculate these parameters for the case of contemporary multi-terawatt experiments using foil targets as well as for anticipated fast-ignition-scale experiments.

  20. Hyperuricemia Is a Risk Factor for the Onset of Impaired Fasting Glucose in Men with a High Plasma Glucose Level: A Community-Based Study

    PubMed Central

    Miyake, Teruki; Kumagi, Teru; Furukawa, Shinya; Hirooka, Masashi; Kawasaki, Keitarou; Koizumi, Mitsuhito; Todo, Yasuhiko; Yamamoto, Shin; Abe, Masanori; Kitai, Kohichiro; Matsuura, Bunzo; Hiasa, Yoichi

    2014-01-01

    Background It is not clear whether elevated uric acid is a risk factor for the onset of impaired fasting glucose after stratifying by baseline fasting plasma glucose levels. We conducted a community-based retrospective longitudinal cohort study to clarify the relationship between uric acid levels and the onset of impaired fasting glucose, according to baseline fasting plasma glucose levels. Methods We enrolled 6,403 persons (3,194 men and 3,209 women), each of whom was 18–80 years old and had >2 annual check-ups during 2003–2010. After excluding persons who had fasting plasma glucose levels ≥6.11 mM and/or were currently taking anti-diabetic agents, the remaining 5,924 subjects were classified into quartiles according to baseline fasting plasma glucose levels. The onset of impaired fasting glucose was defined as fasting plasma glucose ≥6.11 mM during the observation period. Results In the quartile groups, 0.9%, 2.1%, 3.4%, and 20.2% of the men developed impaired fasting glucose, respectively, and 0.1%, 0.3%, 0.5%, and 5.6% of the women developed impaired fasting glucose, respectively (P trend <0.001). After adjusting for age, body mass index, systolic blood pressure, triacylglycerols, high density lipoprotein-cholesterol, creatinine, fatty liver, family history of diabetes, alcohol consumption, and current smoking, uric acid levels were positively associated with onset of impaired fasting glucose in men with highest-quartile fasting plasma glucose levels (adjusted hazard ratio, 1.003; 95% confidence interval, 1.0001–1.005, P = 0.041). Conclusions Among men with high fasting plasma glucose, hyperuricemia may be independently associated with an elevated risk of developing impaired fasting glucose. PMID:25237894

  1. Effects of the fast plasma sheet flow on the geosynchronous magnetic configuration: Geotail and GOES coordinated study

    NASA Astrophysics Data System (ADS)

    Ohtani, S.; Singer, H. J.; Mukai, T.

    2006-01-01

    The present study statistically examines how (or if) the geosynchronous (GOES) magnetic field responds to fast earthward flow observed by the Geotail satellite in the plasma sheet. The change of the GOES H (north-south) component within 15 min of the detection of fast flows, ΔH, is used as a primary measure of the geosynchronous response. It is found that following the detection of fast flows, the geosynchronous magnetic field rarely dipolarizes, but it often becomes more stretched, which is manifested by negative ΔH. This H decrease is not accompanied by any correlated variation of the D (azimuthal) component, suggesting that the associated stretching is not an edge effect of the substorm current wedge formation, but it can be attributed to the intensification of the local tail current. No systematic dependence of ΔH on the satellite separation can be found. On the other hand, the geosynchronous magnetic field tends to dipolarize if it is already stretched significantly, although the associated changes in the H and V (radial) components are not much larger than those in events that are not preconditioned. The flow intensity does not seem to be a controlling factor, either. However, caution needs to be exercised because the present study is not able to address the azimuthal structure of the fast flow. It is concluded that in most events the fast plasma flow does not reach geosynchronous orbit and that the generation of the fast plasma flow in the plasma sheet is not sufficient for causing geosynchronous dipolarization.

  2. Fast-ion measurements with neutron and gamma-ray spectroscopy in thermonuclear plasmas: recent results and future prospects

    NASA Astrophysics Data System (ADS)

    Nocente, M.

    2016-03-01

    A high-performance thermonuclear plasma is a strong source of nuclear radiation, which includes neutron emission from the main fusion reactions and gamma-rays born from the interaction of supra-thermal ions and plasma impurities. Spectroscopic measurements of both types of radiation are an indirect probe of the distribution function of the fast ions leading to nuclear emission. In this paper we present a selection of recent results obtained with neutron and gamma-ray spectroscopy as a means to study the energy distribution of supra-thermal particles in high-performance thermonuclear plasmas. We focus in particular on the advancements made possible by the combination of dedicated instrumentation and detailed models based on the nuclear physics behind the emission. Future developments are finally addressed, especially regarding the availability of compact detectors with spectroscopy capabilities, which open up to a full tomographic reconstruction of the fast-ion velocity space.

  3. Changes of plasma fasting carnitine ester profile in patients with ulcerative colitis

    PubMed Central

    Bene, Judit; Komlósi, Katalin; Havasi, Viktória; Talián, Gábor; Gasztonyi, Beáta; Horváth, Krisztina; Mózsik, Gyula; Hunyady, Béla; Melegh, Béla; Figler, Mária

    2006-01-01

    AIM: To determine the plasma carnitine ester profile in adult patients with ulcerative culitis (UC) and compared with healthy control subjects. METHOD: Using ESI triple quadrupole tandem mass spectrometry, the carnitine ester profile was measured in 44 patients with UC and 44 age- and sex-matched healthy controls. RESULTS: There was no significant difference in the fasting free carnitine level between the patients with UC and the healthy controls. The fasting propionyl- (0.331 ± 0.019 vs 0.392 ± 0.017 μmol/L), butyryl- (0.219 ± 0.014 vs 0.265 ± 0.012), and isovalerylcarnitine (0.111 ± 0.008 vs 0.134 ± 0.008) levels were decreased in the UC patients. By contrast, the level of octanoyl- (0.147 ± 0.009 vs 0.114 ± 0.008), decanoyl- (0.180 ± 0.012 vs 0.137 ± 0.008), myristoyl- (0.048 ± 0.003 vs 0.039 ± 0.003), palmitoyl- (0.128 ± 0.006 vs 0.109 ± 0.004), palmitoleyl- (0.042 ± 0.003 vs 0.031 ± 0.002) and oleylcarnitine (0.183 ± 0.007 vs 0.163 ± 0.007; P < 0.05 in all comparisons) were increased in the patients with UC. CONCLUSION: Our data suggest selective involvement of the carnitine esters in UC patients, probably due to their altered metabolism. PMID:16440427

  4. Experimental study of fast electrons from the interaction of ultra intense laser and solid density plasmas

    NASA Astrophysics Data System (ADS)

    Cho, Byoung-Ick

    A series of experiments have been performed to understand fast electron generation from ultra intense laser-solid interaction, and their transports through a cold material. Using Micro-Electro-Mechanical Systems (MEMS), we contrived various shape of cone and wedge targets. The first set of experiment was for investigating hot electron generations by measuring x-ray production in different energy ranges. Kalpha and hard x-ray yields were compared when the laser was focused into pyramidal shaped cone targets and wedge shaped targets. Hot electron production is highest in the wedge targets irradiated with transverse polarization, though Kalpha is maximized with wedge targets and parallel polarization. These results are explained with particle-in-cell (PIC) simulations utilizing PICLS and OOPIC codes. We also investigate hot electron transport in foil, wedge, and cone targets by observing the transition radiation emitted from the targets rear side along with bremsstrahlung x-ray measurement. Two-dimensional images and spectra of 800 nm coherent transition radiation (CTR) along with ballistic electron transport analysis have revealed the spatial, temporal, and temperature characteristics of hot electron micro-pulses. Various patterns from different target-laser configurations suggest that hot electrons were guided by the strong static electromagnetic fields at the target boundary. Evidence about fast electron guiding in the cone is also observed. CTR at 400 nm showed that two distinct beams of MeV electrons are emitted from the target rear side at the same time. This measurement indicates that two different mechanisms, namely resonance absorption and j x B heating, create two populations of electrons at the targets front side and drive them to different directions, with distinct temperatures and temporal characteristics. This interpretation is consistent with the results from 3D-PIC code Virtual Laser Plasma Laboratory (VLPL).

  5. Supplementation of cheonggukjang and red ginseng cheonggukjang can improve plasma lipid profile and fasting blood glucose concentration in subjects with impaired fasting glucose.

    PubMed

    Shin, Su-Kyung; Kwon, Joong-Ho; Jeong, Yong-Jin; Jeon, Seon-Min; Choi, Ji-Young; Choi, Myung-Sook

    2011-01-01

    This study was conducted to investigate the plasma lipid profile and blood glucose-lowering effects of cheonggukjang (CH) and red ginseng CH (RGCH) in 45 subjects (men:women = 27:18; mean age, 44.9 ± 3.1 years) with impaired fasting glucose (IFG). Subjects were randomly divided into three groups: control (starch, 2 g/day), CH (20 g/day), and RGCH (20 g/day). Each volunteer received his or her daily doses for 8 weeks. The supplementation with CH and RGCH significantly decreased the plasma total cholesterol about 30.0 mg/mL and 37.7 mg/mL, respectively, compared to the initial value. The plasma low-density lipoprotein-cholesterol concentration was also significantly reduced by 29.66% and 23.42% in the CH and RGCH groups, respectively, compared to the initial value. The concentration of plasma non-high-density lipoprotein-cholesterol (107.9 mg/mL) was significantly lowered in the RGCH group compared to the initial value (139.1 mg/mL). The level of erythrocyte thiobarbituric acid-reactive substances was significantly lowered in the CH (6.5 nmol/mL) and RGCH (6.6 nmol/mL) groups compared to the initial value (7.9 nmol/mL and 8.0 nmol/mL, respectively). The ratio of apolipoprotein B and apolipoprotein A-1 concentrations (2.5) was significantly reduced in the CH group compared to the initial value (3.0). The concentration of fasting blood glucose (FBG) was significantly lower in the CH- and RGCH-supplemented groups compared to the initial value. These results suggest that CH and RGCH can lower the FBG concentration and improve the plasma lipid profile in subjects with IFG.

  6. Day-to-day variability of fasting plasma glucose in newly diagnosed type 2 diabetic subjects.

    PubMed

    Ollerton, R L; Playle, R; Ahmed, K; Dunstan, F D; Luzio, S D; Owens, D R

    1999-03-01

    To determine the day-to-day intraindividual variability of fasting plasma glucose (FPG) in newly diagnosed Caucasian type 2 diabetic subjects. A total of 193 newly diagnosed, previously untreated, Caucasian type 2 diabetic subjects (135 men, 58 women) had FPG measured on two consecutive days (FPG1, FPG2). Ethical approval and subjects' full informed consent were obtained. Subjects fasted for 12 h before each study day and rested for at least 30 min before blood was taken. Plasma glucose was analyzed by a glucose oxidase method with intra- and interassay coefficients of variation (CVs) < 2%. Variability of FPG was assessed by comparison of percentage differences (PDs): PD = 100 (FPG2 - FPG1)/FPG1, with averaged FPG (FPGaver = [FPG1 + FPG2]/2). Biological and analytical variability were determined by use of SD2total = SD2biological + SD2analytical, where SD2analytical approximately equal to 2 x (CVglucose measurement)2. Given normally distributed data with zero mean, 95% of daily percentage differences will be expected to fall within a range of +/- 2 SDtotal. Subjects were age 54 +/- 10 years (mean +/- SD) and had BMI of 29.3 +/- 5.3 kg/m2. FPG values for both days were 12.2 +/- 3.4 mmol/l (FPG1) and 12.1 +/- 3.3 mmol/l (FPG2), with a mean paired difference (95% CI) of 0.1 (0.0 to 0.3) mmol/l. The variance of these differences increased with increasing FPGaver. The PDs did not exhibit this effect and were normally distributed (mean -0.6% [-1.7 to 0.4]; SD 7.4% [6.8 to 8.3]), giving a 95% variability (2 SD) of 14.8%. Biological variability (2 SDbiological) was 13.7%. No significant difference in PD was found between men and women (mean difference 1.3% [-1.0 to 3.6]; SDmale 7.4%, SDfemale 7.3%; P = 0.62). A total of 95% of the FPG values for this group of newly diagnosed type 2 diabetic subjects varied within approximately +/- 15% on a daily basis, with approximately 14% caused by biological variability. As these results are expressed in percentage terms, subjects in

  7. Measurements of plasma profiles using a fast swept Langmuir probe in the VINETA-II magnetic reconnection experiment

    NASA Astrophysics Data System (ADS)

    Shesterikov, I.; Von Stechow, A.; Grulke, O.; Stenzel, R.; Klinger, T.

    2017-07-01

    A fast-swept Langmuir probe capable to be biased at a high voltages has been constructed and successfully operated at the VINETA-II magnetic reconnection experiment. The presented circuit has two main features beneficial for fast transient parameter changes in laboratory experiments as, e.g., plasma guns or magnetic reconnection: the implementation simplicity and the high voltage sweep range. This work presents its design and performance for time-dependent measurements of VINETA-II plasmas. The probe is biased with a sinusoidal voltage at a fixed frequency. Current - voltage characteristics are measured along the falling and rising slopes of the probe bias. The sweep frequency is fsweep= 150 kHz. The spatiotemporal evolution of radial plasma profiles is obtained by evaluation of the probe characteristics. The plasma density measurements agree with those derived from a microwave interferometer, demonstrating the reliability of the measurements. As a model plasma system, a plasma gun discharge with typical pulse times of 60 μ s is chosen.

  8. The Prevalence and Associated Factors of Periodontitis According to Fasting Plasma Glucose in the Korean Adults

    PubMed Central

    Hong, Jae Won; Noh, Jung Hyun; Kim, Dong-Jun

    2016-01-01

    Abstract Although the relationship between diabetes and periodontitis is well established, the association between periodontitis and prediabetes has been investigated less extensively. Furthermore, there has been little research on the prevalence of periodontitis among individuals with prediabetes and diabetes as well as in the overall population using nationally representative data. Among 12,406 adults (≥19 years’ old) who participated in the 2012–2013 Korea National Health and Nutrition Examination Survey, a total of 9977 subjects completed oral and laboratory examinations and were included in this analysis. Periodontitis was defined as a community periodontal index score of ≥3 according to the World Health Organization criteria. The fasting plasma glucose level was categorized into the following 5 groups: normal fasting glucose (NFG) 1 (<90 mg/dL), NFG 2 (90–99 mg/dL), impaired fasting glucose (IFG) 1 (100–110 mg/dL), IFG 2 (111–125 mg/dL), and diabetes (≥126 mg/dL). Overall, the weighted prevalence of periodontitis among the Korean adult population was 24.8% (23.3–26.4%) (weight n = 8,455,952/34,086,014). The unadjusted weighted prevalences of periodontitis were 16.7%, 22.8%, 29.6%, 40.7%, and 46.7% in the NFG 1, NFG 2, IFG 1, IFG 2, and diabetes groups, respectively (P < 0.001). After adjusting for age, sex, smoking history, heavy alcohol drinking, college graduation, household income, waist circumference, serum triglyceride level, serum high-density lipoprotein cholesterol level, and the presence of hypertension, the adjusted weighted prevalence of periodontitis increased to 29.7% in the IFG 2 group (P = 0.045) and 32.5% in the diabetes group (P < 0.001), compared with the NFG 1 group (24%). The odds ratios for periodontitis with the above-mentioned variables as covariates were 1.42 (95% confidence interval [CI] 1.14–1.77, P = 0.002) in the diabetes group and 1.33 (95% CI 1.01–1.75, P = 0.044) in the IFG

  9. Fuel cell system logic for differentiating between rapid and normal shutdown commands

    DOEpatents

    Keskula, Donald H.; Doan, Tien M.; Clingerman, Bruce J.

    2000-01-01

    A method of controlling the operation of a fuel cell system wherein each shutdown command for the system is subjected to decision logic which determines whether the command should be a normal shutdown command or rapid shutdown command. If the logic determines that the shutdown command should be a normal shutdown command, then the system is shutdown in a normal step-by-step process in which the hydrogen stream is consumed within the system. If the logic determines that the shutdown command should be a rapid shutdown command, the hydrogen stream is removed from the system either by dumping to atmosphere or routing to storage.

  10. Fasting plasma insulin and the default mode network in women at risk for Alzheimer's disease

    PubMed Central

    Kenna, Heather; Hoeft, Fumiko; Kelley, Ryan; Wroolie, Tonita; DeMuth, Bevin; Reiss, Allan; Rasgon, Natalie

    2016-01-01

    Brain imaging studies in Alzheimer's disease research have demonstrated structural and functional perturbations in the hippocampus and default mode network (DMN). Additional evidence suggests risk for pathological brain aging in association with insulin resistance (IR). This study piloted investigation of associations of IR with DMN-hippocampal functional connectivity among postmenopausal women at risk for Alzheimer's disease. Twenty middle-aged women underwent resting state functional magnetic resonance imaging. Subjects were dichotomized relative to fasting plasma insulin levels (i.e., 8 IU/mL [n 10] and 8 IU/mL [n 10]), and functional connectivity analysis contrasted their respective blood oxygen level-dependent signal correlation between DMN and hippocampal regions. Higher-insulin women had significantly reduced positive associations between the medial prefrontal cortex and bilateral parahippocampal regions extending to the right hippocampus, and conversely, between the left and right hippocampus and medial prefrontal cortex. Neuropsychological data (all within normal ranges) also showed significant differences with respect to executive functioning and global intelligence. The results provide further evidence of deleterious effects of IR on the hippocampus and cognition. Further imaging studies of the IR-related perturbations in DMN-hippocampal functional connectivity are needed. PMID:22770543

  11. Efficiency of fast wave current drive for a weakly relativistic plasma

    SciTech Connect

    Chiu, S.C.; Lin-Liu, Y.R. ); Karney, C.F.F. . Plasma Physics Lab.)

    1993-04-01

    Current drive by fast waves (FWCD) is an important candidate for steady-state operation of tokamaks. Major experiments using this scheme are being carried out on DIII-D. There has been considerable study of the theoretical efficiency of FWCD. In Refs. 4 and 5, the nonrelativistic efficiency of FWCD at arbitrary frequencies was studied. For DIII-D parameters, the results can be considerably different from the Landau and Alfven limits. At the high temperatures of reactors and DIII-D upgrade, relativistic effects become important. In this paper, the relativistic FWCD efficiency for arbitrary frequencies is studied. Assuming that the plasma is weakly relativistic, i.e., T[sub e]/Mc[sup 2] is small, an analytic expression for FWCD is obtained for high resonant energies (U[sub ph]/u[sub Te][much gt]). Comparisons with the results from a numerical code ADJ and the nonrelativistic results shall be made and analytical fits in the whole range of velocities shall be presented.

  12. Efficiency of fast wave current drive for a weakly relativistic plasma

    SciTech Connect

    Chiu, S.C.; Lin-Liu, Y.R.; Karney, C.F.F.

    1993-04-01

    Current drive by fast waves (FWCD) is an important candidate for steady-state operation of tokamaks. Major experiments using this scheme are being carried out on DIII-D. There has been considerable study of the theoretical efficiency of FWCD. In Refs. 4 and 5, the nonrelativistic efficiency of FWCD at arbitrary frequencies was studied. For DIII-D parameters, the results can be considerably different from the Landau and Alfven limits. At the high temperatures of reactors and DIII-D upgrade, relativistic effects become important. In this paper, the relativistic FWCD efficiency for arbitrary frequencies is studied. Assuming that the plasma is weakly relativistic, i.e., T{sub e}/Mc{sup 2} is small, an analytic expression for FWCD is obtained for high resonant energies (U{sub ph}/u{sub Te}{much_gt}). Comparisons with the results from a numerical code ADJ and the nonrelativistic results shall be made and analytical fits in the whole range of velocities shall be presented.

  13. Alcator C-Mod ICRF fast wave antenna design and analysis and expected plasma performance

    NASA Astrophysics Data System (ADS)

    Takase, Y.; Golovato, S.; Porkolab, M.; Becker, H.; Diatchenko, N.; Kochan, S.; McCoy, C.; Pierce, N.

    1989-07-01

    The design and analysis of the fast wave antenna to be used for ICRF heating experiments on the Alcator C-Mod tokamak are described. A movable single-strap low-field-side-launch loop antenna will be used during the initial operation period. Structural analysis against disruption and thermal analysis are performed. Optimized two-strap antennae with twice the surface area are planned for high-power heating experiments. Antenna-plasma coupling studies indicate a poor (<20%) single-pass ion absorption for D(3He), and a radiation resistance of ≳10Ω. Minority ions are not expected to be accelerated to very high energies under typical operating densities (Teff≲50 keV for n¯e≳3×1020m-3), and energetic ions should mainly slow down on ions. The transport of minority ions broadens the energetic minority ion and slowing down profiles and reduces Teff, but the effect is small for n¯e≳3×1020m-3.

  14. Negative relationship between fasting plasma ghrelin concentrations and ad libitum food intake.

    PubMed

    Salbe, Arline D; Tschöp, Matthias H; DelParigi, Angelo; Venti, Colleen A; Tataranni, P Antonio

    2004-06-01

    Ghrelin is a novel GH secretagogue with orexigenic effects. We hypothesized that high fasting plasma ghrelin concentrations (FxGhr) might predict high ad libitum food intake. FxGhr were measured in 30 normoglycemic subjects: 15 Pima Indians (8 male/7 female; age, 32 +/- 7 yr; body weight, 87 +/- 21 kg; mean +/-sd) and 15 Caucasians (12 male/3 female, 36 +/- 8 yr, 94 +/- 26 kg) in energy balance for 3 d before testing. Subjects then self-selected their food ad libitum for the following 3 d. Mean daily energy intake (DEI) was calculated from the weight of foods consumed and expressed as a percent of weight maintenance energy needs. FxGhr were twice as high in Caucasians as in Pima Indians (103 +/- 53 vs. 52 +/- 18 fmol/ml, P < 0.001) and remained higher after adjustment for age, gender, and body weight (P < 0.0001). Neither DEI, nor percent of weight maintenance energy needs, nor percent of calories from fat differed between the races. In both groups, FxGhr were negatively correlated with DEI (r = -0.61, P = 0.01; r = -0.54, P = 0.04, respectively). These negative relationships were not explained by interindividual differences in age, gender, or body weight. This unexpected finding that low FxGhr predict ad libitum food intake suggests that the role of endogenous ghrelin in the regulation of energy homeostasis remains uncertain.

  15. [Genetic determination of fast plasma glucose concentration and correlation with anthropometric indices].

    PubMed

    Jian, Wei-xia; Su, Qing; Luo, Min

    2009-04-01

    To study the genetic determination of fast plasma glucose (FPG) and correlation with its potential correlated traits, anthropometric measures and blood pressure. Two hundred and eighteen Type 2 diabetes mellitus (T2DM) pedigrees composed of 1383 Chinese Han individuals residing in the East and South-East China were analyzed. Univariate variance decomposition analyses were used to estimate the narrow-sense heritability (h(2)) of FPG, anthropometric indices and blood pressure, and bivariate quantitative genetic analyses were used to estimate the genetic and environmental correlations between FPG and anthropometric measures or blood pressure. We found that FPG, blood pressure and all anthropometric indices except for waist to hip ratio were under significant genetic determination, and the h(2) was from 0.28 to 0.43. We did not find significant genetic and environmental correlation between FPG and anthropometric indices and blood pressure. The present study demonstrated that T2DM, obesity and hypertension were controlled by some genetic factors, and FPG shares little common genetic and environmental factors with obesity-related anthropometric indices and blood pressure in our Chinese sample population.

  16. Fasting plasma glucose and serum lipids in patients with primary aldosteronism: a controlled cross-sectional study.

    PubMed

    Matrozova, Joanna; Steichen, Olivier; Amar, Laurence; Zacharieva, Sabina; Jeunemaitre, Xavier; Plouin, Pierre-François

    2009-04-01

    An association between primary aldosteronism and metabolism disorders has been reported. The aim of this retrospective study was to test for this association by comparison between large cohorts of patients with primary aldosteronism and with essential hypertension. We retrieved the records of 460 cases with primary aldosteronism (103 lateralized, 150 not lateralized, and 207 undetermined) and of 1363 controls with essential hypertension individually matched for age and sex. We compared clinical history; blood pressure levels; body mass index; levels of fasting plasma glucose and serum triglycerides; total, high-density lipoprotein, and low-density lipoprotein cholesterol; and the prevalence of diabetes mellitus and impaired fasting glucose among subtypes of primary aldosteronism, as well as between cases with primary aldosteronism and their matched controls. Fasting plasma glucose and serum lipid levels did not differ among the 3 subtypes of primary aldosteronism. The prevalence of impaired fasting glucose was lower in patients with primary aldosteronism than their matched controls, but the prevalence of hyperglycemia (impaired fasting glucose or diabetes mellitus) and blood levels of glucose and lipids did not differ between cases and controls. There was no significant difference between preoperative and postoperative levels of either fasting plasma glucose or serum lipids in patients who underwent adrenalectomy and had follow-up data available. The analysis of this large group of patients with primary aldosteronism and essential hypertension does not confirm a higher prevalence of carbohydrate or lipid metabolism disorders in the former. It is unlikely that the prevalence of metabolic syndrome differs significantly between patients with primary aldosteronism and those with essential hypertension.

  17. Fast pyrobolometers for measurements of plasma heat fluxes and radiation losses in the MST Reversed Field Pinch

    SciTech Connect

    Fiksel, G.; Frank, J.; Holly, D.

    1993-01-07

    Two types of fast bolometers are described for the plasma energy transport study in the Madison Symmetric Torus plasma confinement device. Both types use pyrocrystals of LiTaO[sub 3] or LiNbO[sub 3] as the sensors. One type is used for measurements of the radiated heat losses and is situated at the vacuum shell inner surface. Another type is insertable in the plasma and measures the plasma particle heat flux. The frequency response of the bolometers is measured to be in the 150--200 kHz range. The range of the measured power fluxes is 0.1 W/cm[sup 2] 10 kW/cm[sup 2] and can be adjusted by changing the size of the entrance aperture. The lower limit is determined by the amplifier noise and the frequency bandwidth, the higher limit by destruction of the bolometer sensor.

  18. Fast pyrobolometers for measurements of plasma heat fluxes and radiation losses in the MST Reversed Field Pinch

    SciTech Connect

    Fiksel, G.; Frank, J.; Holly, D.

    1993-01-07

    Two types of fast bolometers are described for the plasma energy transport study in the Madison Symmetric Torus plasma confinement device. Both types use pyrocrystals of LiTaO{sub 3} or LiNbO{sub 3} as the sensors. One type is used for measurements of the radiated heat losses and is situated at the vacuum shell inner surface. Another type is insertable in the plasma and measures the plasma particle heat flux. The frequency response of the bolometers is measured to be in the 150--200 kHz range. The range of the measured power fluxes is 0.1 W/cm{sup 2} 10 kW/cm{sup 2} and can be adjusted by changing the size of the entrance aperture. The lower limit is determined by the amplifier noise and the frequency bandwidth, the higher limit by destruction of the bolometer sensor.

  19. Consumption of wheat aleurone-rich foods increases fasting plasma betaine and modestly decreases fasting homocysteine and LDL-cholesterol in adults.

    PubMed

    Price, Ruth K; Keaveney, Edel M; Hamill, Lesley L; Wallace, Julie M W; Ward, Mary; Ueland, Per M; McNulty, Helene; Strain, J J; Parker, Michael J; Welch, Robert W

    2010-12-01

    There is strong evidence that whole-grain foods protect against heart disease. Although underlying mechanisms and components are unclear, betaine, found at high levels in wheat aleurone, may play a role. We evaluated the effects of a diet high in wheat aleurone on plasma betaine and related measures. In a parallel, single-blinded intervention study, 79 healthy participants (aged 45-65 y, BMI ≥ 25 kg/m(2)) incorporated either aleurone-rich cereal products (27 g/d aleurone) or control products balanced for fiber and macronutrients into their habitual diets for 4 wk. Fasting blood samples were taken at baseline and postintervention (4 wk) from participants. Compared with the control, the aleurone products provided an additional 279 mg/d betaine and resulted in higher plasma betaine (P < 0.001; intervention effect size: 5.2 μmol/L) and lower plasma total homocysteine (tHcy) (P = 0.010; -0.7 μmol/L). Plasma dimethylglycine and methionine, which are products of betaine-mediated homocysteine remethylation, were also higher (P < 0.001; P = 0.027) relative to control. There were no significant effects on plasma choline or B vitamins (folate, riboflavin, and vitamin B-6). However, LDL cholesterol was lower than in the control group (P = 0.037). We conclude that incorporating aleurone-rich products into the habitual diet for 4 wk significantly increases plasma betaine concentrations and lowers tHcy, which is attributable to enhanced betaine-homocysteine methyltransferase-mediated remethylation of homocysteine. Although this supports a role for betaine in the protective effects of whole grains, concomitant decreases in LDL suggest more than one component or mechanism may be responsible.

  20. Generation of Non-Inductive H-Mode Plasmas with 30 MHz Fast Wave Heating in NSTX-U

    NASA Astrophysics Data System (ADS)

    Taylor, G.; Bertelli, N.; Gerhardt, S. P.; Hosea, J. C.; Mueller, D.; Perkins, R. J.; Poli, F. M.; Wilson, J. R.; Raman, R.

    2016-10-01

    A Fusion Nuclear Science Facility based on a spherical tokamak must generate the plasma current (Ip) with little or no central solenoid field. The NSTX-U non-inductive (NI) plasma research program is addressing this goal by developing NI start-up, ramp-up and sustainment scenarios separately. 4 MW of 30 MHz fast wave power is predicted to ramp Ip to 400 kA, a level sufficient to avoid significant shine-through of 90 keV ions from neutral beam injection. In 2010, experiments in NSTX demonstrated that 1.4 MW of 30 MHz high-harmonic fast wave (HHFW) power could generate an Ip = 300 kA H-mode discharge with a NI Ip fraction, fNI, around 0.7 at the maximum axial toroidal field (BT(0)) in NSTX of 0.55 T. NSTX-U is a major upgrade of NSTX that will eventually allow the generation of plasmas with BT(0) up to 1 T. Full wave simulations of 30 MHz HHFW heating in NSTX-U predict reduced FW power loss in the plasma edge as BT(0) is increased. HHFW experiments this year aim to couple 3 - 4 MW of 30 MHz HHFW power into an Ip = 250 - 350 kA plasma with BT(0) up to 0.75 T to generate a fNI = 1 H-mode plasma. These experiments should benefit from the improved fast wave coupling predicted at higher BT(0) in NSTX-U. Work supported by USDOE Contract No. DE-AC02-09CH11466.

  1. Large-amplitude hydromagnetic waves in collisionless relativistic plasma - Exact solution for the fast-mode magnetoacoustic wave

    NASA Technical Reports Server (NTRS)

    Barnes, A.

    1983-01-01

    An exact nonlinear solution is found to the relativistic kinetic and electrodynamic equations (in their hydromagnetic limit) that describes the large-amplitude fast-mode magnetoacoustic wave propagating normal to the magnetic field in a collisionless, previously uniform plasma. It is pointed out that a wave of this kind will be generated by transverse compression of any collisionless plasma. The solution is in essence independent of the detailed form of the particle momentum distribution functions. The solution is obtained, in part, through the method of characteristics; the wave exhibits the familiar properties of steepening and shock formation. A detailed analysis is given of the ultrarelativistic limit of this wave.

  2. Transformation of the ordered internal structures during the acceleration of fast charged particles in a dense plasma focus

    NASA Astrophysics Data System (ADS)

    Kubes, P.; Paduch, M.; Cikhardt, J.; Cikhardtova, B.; Klir, D.; Kravarik, J.; Rezac, K.; Zielinska, E.; Sadowski, M. J.; Szymaszek, A.; Tomaszewski, K.; Zaloga, D.

    2017-07-01

    The paper concerns important differences in the evolution of plasma column structures during the production of fusion neutrons in the first and subsequent neutron pulses, as observed for plasma-focus discharges performed with the deuterium filling. The first neutron pulse, of a more isotropic distribution, is usually produced during the formation of the first big plasmoid. The next neutron pulses can be generated by the fast deuterons moving dominantly in the downstream direction, at the instants of a disruption of the pinch constriction, when other plasmoids are formed during the constriction evolution. In both cases, the fusion neutrons are produced by a beam-target mechanism, and the acceleration of fast electron- and deuteron-beams can be interpreted by transformation and decay of the magnetic field associated with a filamentary structure of the current flow in the plasmoid.

  3. Performance of a Discrete Wavelet Transform for Compressing Plasma Count Data and its Application to the Fast Plasma Investigation on NASA's Magnetospheric Multiscale Mission

    NASA Technical Reports Server (NTRS)

    Barrie, Alexander C.; Yeh, Penshu; Dorelli, John C.; Clark, George B.; Paterson, William R.; Adrian, Mark L.; Holland, Matthew P.; Lobell, James V.; Simpson, David G.; Pollock, Craig J.; hide

    2015-01-01

    Plasma measurements in space are becoming increasingly faster, higher resolution, and distributed over multiple instruments. As raw data generation rates can exceed available data transfer bandwidth, data compression is becoming a critical design component. Data compression has been a staple of imaging instruments for years, but only recently have plasma measurement designers become interested in high performance data compression. Missions will often use a simple lossless compression technique yielding compression ratios of approximately 2:1, however future missions may require compression ratios upwards of 10:1. This study aims to explore how a Discrete Wavelet Transform combined with a Bit Plane Encoder (DWT/BPE), implemented via a CCSDS standard, can be used effectively to compress count information common to plasma measurements to high compression ratios while maintaining little or no compression error. The compression ASIC used for the Fast Plasma Investigation (FPI) on board the Magnetospheric Multiscale mission (MMS) is used for this study. Plasma count data from multiple sources is examined: resampled data from previous missions, randomly generated data from distribution functions, and simulations of expected regimes. These are run through the compression routines with various parameters to yield the greatest possible compression ratio while maintaining little or no error, the latter indicates that fully lossless compression is obtained. Finally, recommendations are made for future missions as to what can be achieved when compressing plasma count data and how best to do so.

  4. Maternal and child nutritional supplementation are inversely associated with fasting plasma glucose concentration in young Guatemalan adults.

    PubMed

    Conlisk, Andrea J; Barnhart, Huiman X; Martorell, Reynaldo; Grajeda, Ruben; Stein, Aryeh D

    2004-04-01

    Cardiovascular disease and diabetes may be programmed early in life by abnormal development associated with undernutrition. We investigated whether maternal nutritional status (MNS; height, pregnancy weight gain, nonpregnant BMI, and prenatal supplementation) or childhood nutritional status (CNS; birth weight, length, ponderal index, height-for-age Z-score at 24 mo, and supplementation from 0 to 24 mo) were related to fasting plasma glucose levels in rural-born Guatemalan adults. We studied 209 men and 220 women (mean age 24.4 y) who were involved in a randomized trial of nutritional supplementation of their mothers during pregnancy and during their early childhoods, conducted from 1969 to 1977. In 2 villages, residents were offered Atole (3.8 MJ and 64 g protein/L); 2 other villages were offered Fresco (1.4 MJ/L, no protein). No associations were observed between anthropometric measures of MNS or CNS and fasting plasma glucose levels. In subgroup analyses, inverse associations (all P < 0.15) with birth size were found among women born to fatter mothers, women with low supplement intake, men born to short mothers, and men more severely stunted at 24 mo. Prenatal supplementation was inversely associated with fasting plasma glucose among women [-0.40 +/- 0.17 mmol/(L. MJ. d), P = 0.02]. Among men, postnatal intake of supplementation of 0.10 to 0.20 MJ/d was associated with up to a 0.56 mmol/L reduction in fasting plasma glucose (P = 0.03), but intake in excess of 0.20 MJ/d provided no added benefit. Among women, the benefit of postnatal supplementation was restricted to those born thin (test for interaction P = 0.10). Improving the nutritional status of undernourished women and children may have positive long-term consequences.

  5. 40 CFR 1065.525 - Engine starting, restarting, and shutdown.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Performing an Emission Test Over Specified Duty Cycles § 1065.525 Engine starting, restarting, and shutdown. (a) For test intervals that require...

  6. 40 CFR 1065.525 - Engine starting, restarting, and shutdown.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Performing an Emission Test Over Specified Duty Cycles § 1065.525 Engine starting, restarting, and shutdown. (a) For test intervals that require...

  7. 40 CFR 1065.930 - Engine starting, restarting, and shutdown.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Field Testing and Portable Emission Measurement Systems § 1065.930 Engine starting, restarting, and shutdown. Unless the standard-setting part specifies...

  8. Fuel cell system shutdown with anode pressure control

    DOEpatents

    Clingerman, Bruce J.; Doan, Tien M.; Keskula, Donald H.

    2002-01-01

    A venting methodology and pressure sensing and vent valving arrangement for monitoring anode bypass valve operating during the normal shutdown of a fuel cell apparatus of the type used in vehicle propulsion systems. During a normal shutdown routine, the pressure differential between the anode inlet and anode outlet is monitored in real time in a period corresponding to the normal closing speed of the anode bypass valve and the pressure differential at the end of the closing cycle of the anode bypass valve is compared to the pressure differential at the beginning of the closing cycle. If the difference in pressure differential at the beginning and end of the anode bypass closing cycle indicates that the anode bypass valve has not properly closed, a system controller switches from a normal shutdown mode to a rapid shutdown mode in which the anode inlet is instantaneously vented by rapid vents.

  9. Startup, Shutdown, & Malfunction (SSM) Emissions at Industrial Facilities

    EPA Pesticide Factsheets

    EPA issued a final action to ensure states have plans in place that are fully consistent with the Clean Air Act and recent court decisions concerning startup, shutdown and malfunction (SSM) operations.

  10. Fuel Supply Shutdown Facility Interim Operational Safety Requirements

    SciTech Connect

    BENECKE, M.W.

    2000-09-06

    The Interim Operational Safety Requirements for the Fuel Supply Shutdown (FSS) Facility define acceptable conditions, safe boundaries, bases thereof, and management of administrative controls to ensure safe operation of the facility.

  11. 46 CFR 153.296 - Emergency shutdown stations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., a cargo pump, or a water spray system, must be of a type that will not defeat the operation of other... this part. (e) Each emergency shutdown station must have the controls necessary to stop all cargo...

  12. Alfvén eigenmode stability and fast ion loss in DIII-D and ITER reversed magnetic shear plasmas

    NASA Astrophysics Data System (ADS)

    Van Zeeland, M. A.; Gorelenkov, N. N.; Heidbrink, W. W.; Kramer, G. J.; Spong, D. A.; Austin, M. E.; Fisher, R. K.; García Muñoz, M.; Gorelenkova, M.; Luhmann, N.; Murakami, M.; Nazikian, R.; Pace, D. C.; Park, J. M.; Tobias, B. J.; White, R. B.

    2012-09-01

    Neutral beam injection into reversed-magnetic shear DIII-D plasmas produces a variety of Alfvénic activity including toroidicity-induced Alfvén eigenmodes (TAEs) and reversed shear Alfvén eigenmodes (RSAEs). With measured equilibrium profiles as inputs, the ideal MHD code NOVA is used to calculate eigenmodes of these plasmas. The postprocessor code NOVA-K is then used to perturbatively calculate the actual stability of the modes, including finite orbit width and finite Larmor radius effects, and reasonable agreement with the spectrum of observed modes is found. Using experimentally measured mode amplitudes, fast ion orbit following simulations have been carried out in the presence of the NOVA calculated eigenmodes and are found to reproduce the dominant energy, pitch and temporal evolution of the losses measured using a large bandwidth scintillator diagnostic. The same analysis techniques applied to a DT 8 MA ITER steady-state plasma scenario with reversed-magnetic shear and both beam ion and alpha populations show Alfvén eigenmode instability. Both RSAEs and TAEs are found to be unstable with maximum growth rates occurring for toroidal mode number n = 6 and the majority of the drive coming from fast ions injected by the 1 MeV negative ion beams. AE instability due to beam ion drive is confirmed by the non-perturbative code TAEFL. Initial fast ion orbit following simulations using the unstable modes with a range of amplitudes (δB/B = 10-5-10-3) have been carried out and show negligible fast ion loss. The lack of fast ion loss is a result of loss boundaries being limited to large radii and significantly removed from the actual modes themselves.

  13. Biochemical diagnosis of phaeochromocytoma using plasma-free normetanephrine, metanephrine and methoxytyramine: importance of supine sampling under fasting conditions.

    PubMed

    Därr, Roland; Pamporaki, Christina; Peitzsch, Mirko; Miehle, Konstanze; Prejbisz, Aleksander; Peczkowska, Mariola; Weismann, Dirk; Beuschlein, Felix; Sinnott, Richard; Bornstein, Stefan R; Neumann, Hartmut P; Januszewicz, Andrzej; Lenders, Jacques; Eisenhofer, Graeme

    2014-04-01

    To document the influences of blood sampling under supine fasting versus seated nonfasting conditions on diagnosis of phaeochromocytomas and paragangliomas (PPGL) using plasma concentrations of normetanephrine, metanephrine and methoxytyramine. Biochemical testing for PPGL was performed on 762 patients at six centres, two of which complied with requirements for supine sampling after an overnight fast and four of which did not. Phaeochromocytomas and paragangliomas were found in 129 patients (67 noncompliant, 62 compliant) and not in 633 patients (195 noncompliant, 438 compliant). Plasma concentrations of normetanephrine and methoxytyramine did not differ between compliant and noncompliant sampling conditions in patients with PPGL but were 49-51% higher in patients without PPGL sampled under noncompliant compared with compliant conditions. The 97·5 percentiles of distributions were also higher under noncompliant compared with compliant conditions for normetanephrine (1·29 vs 0·79 nmol/l), metanephrine (0·49 vs 0·41 nmol/l) and methoxytyramine (0·42 vs 0·18 nmol/l). Use of upper cut-offs established from seated nonfasting sampling conditions resulted in substantially decreased diagnostic sensitivity (98% vs 85%). In contrast, use of upper cut-offs established from supine fasting conditions resulted in decreased diagnostic specificity for testing under noncompliant compared with compliant conditions (71% vs 95%). High diagnostic sensitivity of plasma normetanephrine, metanephrine and methoxytyramine for the detection of PPGL can only be guaranteed using upper cut-offs of reference intervals established with blood sampling under supine fasting conditions. With such cut-offs, sampling under seated nonfasting conditions can lead to a 5·7-fold increase in false-positive results necessitating repeat sampling under supine fasting conditions. © 2013 John Wiley & Sons Ltd.

  14. In Flight Calibration of the Magnetospheric Multiscale Mission Fast Plasma Investigation

    NASA Technical Reports Server (NTRS)

    Barrie, Alexander C.; Gershman, Daniel J.; Gliese, Ulrik; Dorelli, John C.; Avanov, Levon A.; Salo, Chad L.; Tucker, Corey J.; Holland, Mathew P.; Pollock, Craig J.

    2015-01-01

    The Fast Plasma Investigation (FPI) on the Magnetospheric Multiscale mission (MMS) combines data from eight spectrometers, each with four deflection states, into a single map of the sky. Any systematic discontinuity, artifact, noise source, etc. present in this map may be incorrectly interpreted as legitimate data and incorrect conclusions reached. For this reason it is desirable to have all spectrometers return the same output for a given input, and for this output to be low in noise sources or other errors. While many missions use statistical analyses of data to calibrate instruments in flight, this process is difficult with FPI for two reasons: 1. Only a small fraction of high resolution data is downloaded to the ground due to bandwidth limitations and 2: The data that is downloaded is, by definition, scientifically interesting and therefore not ideal for calibration. FPI uses a suite of new tools to calibrate in flight. A new method for detection system ground calibration has been developed involving sweeping the detection threshold to fully define the pulse height distribution. This method has now been extended for use in flight as a means to calibrate MCP voltage and threshold (together forming the operating point) of the Dual Electron Spectrometers (DES) and Dual Ion Spectrometers (DIS). A method of comparing higher energy data (which has low fractional voltage error) to lower energy data (which has a higher fractional voltage error) will be used to calibrate the high voltage outputs. Finally, a comparison of pitch angle distributions will be used to find remaining discrepancies among sensors.

  15. Combined fast selective reduction using Mn-based catalysts and nonthermal plasma for NOx removal.

    PubMed

    Chen, Jun Xiang; Pan, Kuan Lun; Yu, Sheng Jen; Yen, Shaw Yi; Chang, Moo Been

    2017-07-26

    In this study, the concept of fast SCR for NO reduction with NH3 as reducing agent is realized via the combination of nonthermal plasma (NTP) with Mn-based catalyst. Experimental results indicate that 10% wt. Mn-Ce-Ni/TiO2 possesses better physical and chemical properties of surface, resulting in higher NO removal efficiency if compared with 10% wt. Mn-Ce/TiO2 and 10% wt. Mn-Ce-Cu/TiO2. Mn-Ce-Ni/TiO2 of 10% wt. achieves 100% NOx conversion at 150 °C, while 10% wt. Mn-Ce/TiO2 and 10% wt. Mn-Ce-Cu/TiO2 need to be operated at a temperature above 200 °C for 100% NOx conversion. However, NO conversion achieved with 10% wt. Mn-Ce-Ni/TiO2 is significantly reduced as H2O(g) and SO2 are introduced into the SCR system simultaneously. Further, two-stage system (SCR with DBD) is compared with the catalyst-alone for NOx conversion and N2 selectivity. The results indicate that 100% NOx conversion can be achieved with two-stage system at 100 °C, while N2 selectivity reaches 80%. Importantly, NOx conversion achieved with two-stage system could maintain >95% in the presence of C2H4, CO, SO2, and H2O(g), indicating that two-stage system has better tolerance for complicated gas composition. Overall, this study demonstrates that combining NTP with Mn-based catalyst is effective in reducing NOx emission at a low temperature (≤200 °C) and has good potential for industrial application.

  16. FAST MAGNETIC FIELD AMPLIFICATION IN THE EARLY UNIVERSE: GROWTH OF COLLISIONLESS PLASMA INSTABILITIES IN TURBULENT MEDIA

    SciTech Connect

    Falceta-Gonçalves, D.; Kowal, G.

    2015-07-20

    In this work we report on a numerical study of the cosmic magnetic field amplification due to collisionless plasma instabilities. The collisionless magnetohydrodynamic equations derived account for the pressure anisotropy that leads, in specific conditions, to the firehose and mirror instabilities. We study the time evolution of seed fields in turbulence under the influence of such instabilities. An approximate analytical time evolution of the magnetic field is provided. The numerical simulations and the analytical predictions are compared. We found that (i) amplification of the magnetic field was efficient in firehose-unstable turbulent regimes, but not in the mirror-unstable models; (ii) the growth rate of the magnetic energy density is much faster than the turbulent dynamo; and (iii) the efficient amplification occurs at small scales. The analytical prediction for the correlation between the growth timescales and pressure anisotropy is confirmed by the numerical simulations. These results reinforce the idea that pressure anisotropies—driven naturally in a turbulent collisionless medium, e.g., the intergalactic medium, could efficiently amplify the magnetic field in the early universe (post-recombination era), previous to the collapse of the first large-scale gravitational structures. This mechanism, though fast for the small-scale fields (∼kpc scales), is unable to provide relatively strong magnetic fields at large scales. Other mechanisms that were not accounted for here (e.g., collisional turbulence once instabilities are quenched, velocity shear, or gravitationally induced inflows of gas into galaxies and clusters) could operate afterward to build up large-scale coherent field structures in the long time evolution.

  17. In Flight Calibration of the Magnetospheric Multisale Mission Fast Plasma Investigation: Initial Flight Result

    NASA Astrophysics Data System (ADS)

    Barrie, A.; Gliese, U.; Gershman, D. J.; Avanov, L. A.; Rager, A. C.; Pollock, C. J.; Dorelli, J.

    2015-12-01

    The Fast Plasma Investigation (FPI) on the Magnetospheric Multiscale mission (MMS) combines data from eight spectrometers, each with four deflection states, into a single map of the sky. Any systematic discontinuity, artifact, noise source, etc. present in this map may be incorrectly interpreted as legitimate data and incorrect conclusions reached. For this reason it is desirable to have all spectrometers return the same output for a given input, and for this output to be low in noise sources or other errors. While many missions use statistical analyses of data to calibrate instruments in flight, this process is difficult with FPI for two reasons: 1. Only a small fraction of high resolution data is downloaded to the ground due to bandwidth limitations and 2: The data that is downloaded is, by definition, scientifically interesting and therefore not ideal for calibration. FPI uses a suite of new tools to calibrate in flight. A new method for detection system ground calibration has been developed involving sweeping the detection threshold to fully define the pulse height distribution. This method has now been extended for use in flight as a means to calibrate MCP voltage and threshold (together forming the operating point) of the Dual Electron Spectrometers (DES) and Dual Ion Spectrometers (DIS). A method of comparing higher energy data (which has low fractional voltage error) to lower energy data (which has a higher fractional voltage error) will be used to calibrate the high voltage outputs. Finally, a comparison of pitch angle distributions will be used to find remaining discrepancies among sensors. Initial flight results from the four MMS observatories will be discussed here. Specifically, data from initial commissioning, inter-instrument cross calibration and interference testing, and initial Phase1A routine calibration results. Success and performance of the in flight calibration as well as deviation from the ground calibration will be discussed.

  18. Fast screening of analytes for chemical reactions by reactive low-temperature plasma ionization mass spectrometry.

    PubMed

    Zhang, Wei; Huang, Guangming

    2015-11-15

    Approaches for analyte screening have been used to aid in the fine-tuning of chemical reactions. Herein, we present a simple and straightforward analyte screening method for chemical reactions via reactive low-temperature plasma ionization mass spectrometry (reactive LTP-MS). Solution-phase reagents deposited on sample substrates were desorbed into the vapor phase by action of the LTP and by thermal desorption. Treated with LTP, both reagents reacted through a vapor phase ion/molecule reaction to generate the product. Finally, protonated reagents and products were identified by LTP-MS. Reaction products from imine formation reaction, Eschweiler-Clarke methylation and the Eberlin reaction were detected via reactive LTP-MS. Products from the imine formation reaction with reagents substituted with different functional groups (26 out of 28 trials) were successfully screened in a time of 30 s each. Besides, two short-lived reactive intermediates of Eschweiler-Clarke methylation were also detected. LTP in this study serves both as an ambient ionization source for analyte identification (including reagents, intermediates and products) and as a means to produce reagent ions to assist gas-phase ion/molecule reactions. The present reactive LTP-MS method enables fast screening for several analytes from several chemical reactions, which possesses good reagent compatibility and the potential to perform high-throughput analyte screening. In addition, with the detection of various reactive intermediates (intermediates I and II of Eschweiler-Clarke methylation), the present method would also contribute to revealing and elucidating reaction mechanisms. Copyright © 2015 John Wiley & Sons, Ltd.

  19. Sex and age affect agreement between fasting plasma glucose and glycosylated hemoglobin for diagnosis of dysglycemia.

    PubMed

    Lorenzo-Medina, Mercedes; Uranga, Begoña; Rus, Antonio; Martínez, Rosa; Puertas, Carolina; Blanco, María Dolores; Casís, Ernesto; Corcoy, Rosa

    To assess agreement between fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c) levels for diagnosis of dysglycemia (diabetes and risk of diabetes), overall and depending on clinical characteristics. The study enrolled 1020 adult subjects without drug-treated diabetes who underwent a laboratory test at a Spanish health care center. The criteria for dysglycemia of the American Diabetes Association were used. A logistic regression analysis was used to predict de novo diagnosis of dysglycemia based on sex, age, body mass index, anemia, and iron levels. Overall prevalence of dysglycemia was 28.04%, and was identified by FPG only in 13.63% of subjects, by both FPG and HbA1c in 7.65%, and by HbA1c only in 6.76% (de novo diagnoses). Independent predictors of de novo diagnoses based on HbA1c were female sex (odds ratio [OR]: 2.119, 95% confidence interval [CI]: 1.133-4.020; p<0.020), age (OR for 42-56 years: 2.541, 95% CI: 0.634-17.140; OR for ≥57 years: 5.656, 95% CI: 1.516-36.980; overall p<0.007), and serum ferritin levels (borderline significance). In this study population, agreement between FPG and HbA1c for diagnosis of dysglycemia was poor, with FPG being the test that identified more subjects. De novo diagnoses based on HbA1c were more common in females and increased with age. Copyright © 2017 SEEN y SED. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. Effect of chromium supplementation on glycated hemoglobin and fasting plasma glucose in patients with diabetes mellitus.

    PubMed

    Yin, Raynold V; Phung, Olivia J

    2015-02-13

    Chromium (Cr) is a trace element involved in glucose homeostasis. We aim to evaluate and quantify the effects of Cr supplementation on A1C and FPG in patients with T2DM. A systematic literature search of Pubmed, EMBASE and the Cochrane Library (from database inception to 11/2014) with no language restrictions sought RCTs or cohort studies evaluating Cr supplementation in T2DM vs control and reporting either change in glycated hemoglobin (A1C) or fasting plasma glucose (FPG). Meta-analysis was conducted on each subtype of Cr supplement separately, and was analyzed by random effects model to yield the weighted mean differences (WMD) and 95% confidence intervals (CIs). Heterogeneity was assessed by using the I(2) statistic. A total of 14 RCTs (n=875 participants, mean age range: 30 to 83 years old, 8 to 24 weeks of follow-up) were identified (Cr chloride: n=3 study, Cr picolinate: n=5 study, brewer's yeast: n=4 study and Cr yeast: n=3 study). Compared with placebo, Cr yeast, brewer's yeast and Cr picolinate did not show statistically significant effects on A1C. Furthermore, compared to control, Cr chloride, Cr yeast and Cr picolinate showed no effect on FPG, however, brewer's yeast showed a statistically significant decrease in FPG -19.23 mg/dL (95% CI=-35.30 to -3.16, I(2)=21%, n=137). Cr supplementation with brewer's yeast may provide marginal benefits in lowering FPG in patients with T2DM compared to placebo however it did not have any effect on A1C.

  1. In Flight Calibration of the Magnetospheric Multiscale Mission Fast Plasma Investigation

    NASA Technical Reports Server (NTRS)

    Barrie, Alexander C.; Gershman, Daniel J.; Gliese, Ulrik; Dorelli, John C.; Avanov, Levon A.; Rager, Amy C.; Schiff, Conrad; Pollock, Craig J.

    2015-01-01

    The Fast Plasma Investigation (FPI) on the Magnetospheric Multiscale mission (MMS) combines data from eight spectrometers, each with four deflection states, into a single map of the sky. Any systematic discontinuity, artifact, noise source, etc. present in this map may be incorrectly interpreted as legitimate data and incorrect conclusions reached. For this reason it is desirable to have all spectrometers return the same output for a given input, and for this output to be low in noise sources or other errors. While many missions use statistical analyses of data to calibrate instruments in flight, this process is insufficient with FPI for two reasons: 1. Only a small fraction of high resolution data is downloaded to the ground due to bandwidth limitations and 2: The data that is downloaded is, by definition, scientifically interesting and therefore not ideal for calibration. FPI uses a suite of new tools to calibrate in flight. A new method for detection system ground calibration has been developed involving sweeping the detection threshold to fully define the pulse height distribution. This method has now been extended for use in flight as a means to calibrate MCP voltage and threshold (together forming the operating point) of the Dual Electron Spectrometers (DES) and Dual Ion Spectrometers (DIS). A method of comparing higher energy data (which has low fractional voltage error) to lower energy data (which has a higher fractional voltage error) will be used to calibrate the high voltage outputs. Finally, a comparison of pitch angle distributions will be used to find remaining discrepancies among sensors.

  2. Fasting and diet content affect stress-induced changes in plasma glucose and cortisol in Juvenile chinook salmon. [Oncorhynchus tshawytscha

    SciTech Connect

    Barton, B.A.; Schreck, C.B. ); Fowler, L.G. )

    1988-01-01

    Juvenile chinook salmon (Oncorhynchus tshawytscha) reared on low-, medium-, or high-lipid diets for 18 weeks were either kept on their respective diets or fasted for 20 d; then they were subjected to a 30-s handling stress or to handling plus continuous confinement. In fish that were handled but not confined, poststress hyperglycemia was greatest in fed fish that received the high-lipid diet and was generally lower in fasted than in fed fish. Plasma cortisol elevations in response to handling or handling plus confinement stress were not appreciably affected by diet type or fasting. The result indicated that prior feeding regimes and the types of diet fed should be considered when one is interpreting the magnitude of hyperglycemic stress responses in juvenile chinook salmon.

  3. Risk impact of BWR technical specifications requirements during shutdown

    SciTech Connect

    Staple, B.D.; Kirk, H.K.; Yakle, J.

    1994-10-01

    This report presents an application of probabilistic models and risk based criteria for determining the risk impact of the Limiting Conditions of Operations (LCOs) in the Technical Specifications (TSs) of a boiling water reactor during shutdown. This analysis studied the risk impact of the current requirements of Allowed Outage Times (AOTs) and Surveillance Test Intervals (STIs) in eight Plant Operational States (POSs) which encompass power operations, shutdown, and refueling. This report also discusses insights concerning TS action statements.

  4. Acceptance test report for the safety class shutdown system

    SciTech Connect

    Zuroff, W.F.

    1996-10-17

    This document provides the Acceptance Test Report for the successful testing of the Safety Shutdown Circuit. The test was done in accordance with the requirements that were defined in WHC-SD-WM-SCH-003, Interim Stabilization Safety Class Trip Circuit CGI Dedication Criteria. The actual test procedure document was contained in WHC-SD-WM-ATP-185, Acceptance Test Procedure for the Safety Class Shutdown System.

  5. Heat flux of fast electrons to the limiter in lower hybrid current drive plasma on WT-3

    NASA Astrophysics Data System (ADS)

    Maekawa, T.; Nakamura, M.; Komatsu, T.; Kishino, T.; Kishigami, Y.; Makino, K.; Maehara, T.; Minami, T.; Hanada, K.; Iida, M.; Terumichi, Y.; Tanaka, S.

    1992-10-01

    The heat flux of fast electrons to the local limiter in LHCD plasmas in WT-3 has been investigated by thermal measurement of the limiter. The amount of the heat flux (PFE) is found to be about on third of the net radiofrequency power (Prf) injected into the plasma for various discharge conditions. The results combined with other measurements show that the confinement of fast electrons deteriorates as Prf increases. This direct loss of fast electrons is one of the causes of the degradation of the current drive efficiency. Heat transport of the bulk electrons is also found to increase as Prf increases. Experimental results indicate that a significant part of the remaining RF power (2Prf/3) flows to the bulk electrons. The slowing down power of fast electrons in the energy range above several tens of keV is estimated to be quite small compared with 2Prf/3, suggesting that a significant part of the remaining power flows to the bulk electrons via other channels. A plausible channel is the absorption of RF power via lower energy electrons by an upshift of the parallel refractive index of the injected lower hybrid waves. This seems to be another cause of the degradation of the current drive efficiency

  6. Passive shut-down heat removal system

    DOEpatents

    Hundal, Rolv; Sharbaugh, John E.

    1988-01-01

    An improved shut-down heat removal system for a liquid metal nuclear reactor of the type having a vessel for holding hot and cold pools of liquid sodium is disclosed herein. Generally, the improved system comprises a redan or barrier within the reactor vessel which allows an auxiliary heat exchanger to become immersed in liquid sodium from the hot pool whenever the reactor pump fails to generate a metal-circulating pressure differential between the hot and cold pools of sodium. This redan also defines an alternative circulation path between the hot and cold pools of sodium in order to equilibrate the distribution of the decay heat from the reactor core. The invention may take the form of a redan or barrier that circumscribes the inner wall of the reactor vessel, thereby defining an annular space therebetween. In this embodiment, the bottom of the annular space communicates with the cold pool of sodium, and the auxiliary heat exchanger is placed in this annular space just above the drawn-down level that the liquid sodium assumes during normal operating conditions. Alternatively, the redan of the invention may include a pair of vertically oriented, concentrically disposed standpipes having a piston member disposed between them that operates somewhat like a pressure-sensitive valve. In both embodiments, the cessation of the pressure differential that is normally created by the reactor pump causes the auxiliary heat exchanger to be immersed in liquid sodium from the hot pool. Additionally, the redan in both embodiments forms a circulation flow path between the hot and cold pools so that the decay heat from the nuclear core is uniformly distributed within the vessel.

  7. Preliminary Evaluation of Removing Used Nuclear Fuel from Shutdown Sites

    SciTech Connect

    Maheras, Steven J.; Best, Ralph E.; Ross, Steven B.; Buxton, Kenneth A.; England, Jeffery L.; McConnell, Paul E.

    2013-09-30

    This report fulfills the M2 milestone M2FT-13PN0912022, “Stranded Sites De-Inventorying Report.” In January 2013, the U.S. Department of Energy (DOE) issued the Strategy for the Management and Disposal of Used Nuclear Fuel and High-Level Radioactive Waste (DOE 2013). Among the elements contained in this strategy is an initial focus on accepting used nuclear fuel from shutdown reactor sites. This focus is consistent with the recommendations of the Blue Ribbon Commission on America’s Nuclear Future, which identified removal of stranded used nuclear fuel at shutdown sites as a priority so that these sites may be completely decommissioned and put to other beneficial uses (BRC 2012). Shutdown sites are defined as those commercial nuclear power reactor sites where the nuclear power reactors have been shut down and the site has been decommissioned or is undergoing decommissioning. In this report, a preliminary evaluation of removing used nuclear fuel from 12 shutdown sites was conducted. The shutdown sites were Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, Zion, Crystal River, Kewaunee, and San Onofre. These sites have no other operating nuclear power reactors at their sites and have also notified the U.S. Nuclear Regulatory Commission that their reactors have permanently ceased power operations and that nuclear fuel has been permanently removed from their reactor vessels. Shutdown reactors at sites having other operating reactors are not included in this evaluation.

  8. A fast, magnetics-free flux surface estimation and q-profile reconstruction algorithm for feedback control of plasma profiles

    NASA Astrophysics Data System (ADS)

    Hommen, G.; de Baar, M.; Citrin, J.; de Blank, H. J.; Voorhoeve, R. J.; de Bock, M. F. M.; Steinbuch, M.; contributors, JET-EFDA

    2013-02-01

    The flux surfaces' layout and the magnetic winding number q are important quantities for the performance and stability of tokamak plasmas. Normally, these quantities are iteratively derived by solving the plasma equilibrium for the poloidal and toroidal flux. In this work, a fast, non-iterative and magnetics-free numerical method is proposed to estimate the shape of the flux surfaces by an inward propagation of the plasma boundary shape, as can be determined for example by optical boundary reconstruction described in Hommen (2010 Rev. Sci. Instrum. 81 113504), toward the magnetic axis, as can be determined independently with the motional Stark effect (MSE) diagnostic. Flux surfaces are estimated for various plasma regimes in the ITER, JET and MAST tokamaks and are compared with results of CRONOS reconstructions and simulations, showing agreement to within 1% of the minor radius for almost all treated plasmas. The availability of the flux surface shapes combined with the pitch angles measured using MSE allow the reconstruction of the plasma q-profile, by evaluating the contour-integral over the flux surfaces of the magnetic field pitch angle. This method provides a direct and exact measure of the q-profile for arbitrary flux surface shapes, which does not rely on magnetic measurements. Results based on estimated flux surface shapes show agreement with CRONOS q-profiles of better than 10%. The impact of the shape of the flux surfaces on the q-profile, particularly the profiles of elongation and Shafranov shift, and offsets in plasma boundary and the magnetic axis are assessed. OFIT+ was conceived for real-time plasma profile control experiments and advanced tokamak operation, and provides quickly and reliably the mapping of actuators and sensors to the minor radius as well as the plasma q-profile, independent of magnetic measurements.

  9. Microwave plasma generation by the fast rotation and slow pulsation of resonant fields in a cylindrical cavity

    NASA Astrophysics Data System (ADS)

    Hasegawa, Yuichi; Nakamura, Keiji; Lubomirsky, Dima; Park, Soonam; Kobayashi, Satoru; Sugai, Hideo

    2017-04-01

    A digitally controlled solid-state microwave generator allowing variable frequency operation and precise phase control is adopted for plasma generation. In this study, a resonant cylindrical cavity is used as a microwave applicator in place of conventional waveguides. In order to improve the plasma uniformity, the TE111 mode is agitated by injecting microwaves into the cavity from two spatially orthogonal directions, with a temporal phase difference ϕ. Theoretical analyses and finite-difference time-domain simulations derive the following effects of the phase control. In the case of ϕ = ±π/2, fast rotation of the cavity field takes place with a rotational frequency of ω/2π (= 2.4-2.5 GHz), where ω denotes the microwave angular frequency. On the other hand, when ϕ is linearly modulated in time with a low frequency of Ω/2π (= 0.1-1000 Hz), slow pulsation takes place, in which the cavity field alternately excites a circular rotation and a standing oscillation at the modulation frequency. These effects are experimentally confirmed in microwave discharges in argon at 0.1-20 Torr with total injection powers from 50 to 800 W. Two-dimensional images of the optical emission from the generated plasma show that both the fast rotation and slow pulsation improve azimuthal plasma uniformity.

  10. Signal enhancement of neutral He emission lines by fast electron bombardment of laser-induced He plasma

    SciTech Connect

    Suyanto, Hery; Pardede, Marincan; Hedwig, Rinda; Marpaung, Alion Mangasi; Ramli, Muliadi; Lie, Tjung Jie; Kurniawan, Koo Hendrik; Abdulmadjid, Syahrun Nur; Tjia, May On; Kagawa, Kiichiro

    2016-08-15

    A time-resolved spectroscopic study is performed on the enhancement signals of He gas plasma emission using nanosecond (ns) and picosecond (ps) lasers in an orthogonal configuration. The ns laser is used for the He gas plasma generation and the ps laser is employed for the ejection of fast electrons from a metal target, which serves to excite subsequently the He atoms in the plasma. The study is focused on the most dominant He I 587.6 nm and He I 667.8 nm emission lines suggested to be responsible for the He-assisted excitation (HAE) mechanism. The time-dependent intensity enhancements induced by the fast electrons generated with a series of delayed ps laser ablations are deduced from the intensity time profiles of both He emission lines. The results clearly lead to the conclusion that the metastable excited triplet He atoms are actually the species overwhelmingly produced during the recombination process in the ns laser-induced He gas plasma. These metastable He atoms are believed to serve as the major energy source for the delayed excitation of analyte atoms in ns laser-induced breakdown spectroscopy (LIBS) using He ambient gas.

  11. Signal enhancement of neutral He emission lines by fast electron bombardment of laser-induced He plasma

    NASA Astrophysics Data System (ADS)

    Suyanto, Hery; Pardede, Marincan; Hedwig, Rinda; Marpaung, Alion Mangasi; Ramli, Muliadi; Lie, Tjung Jie; Abdulmadjid, Syahrun Nur; Kurniawan, Koo Hendrik; Tjia, May On; Kagawa, Kiichiro

    2016-08-01

    A time-resolved spectroscopic study is performed on the enhancement signals of He gas plasma emission using nanosecond (ns) and picosecond (ps) lasers in an orthogonal configuration. The ns laser is used for the He gas plasma generation and the ps laser is employed for the ejection of fast electrons from a metal target, which serves to excite subsequently the He atoms in the plasma. The study is focused on the most dominant He I 587.6 nm and He I 667.8 nm emission lines suggested to be responsible for the He-assisted excitation (HAE) mechanism. The time-dependent intensity enhancements induced by the fast electrons generated with a series of delayed ps laser ablations are deduced from the intensity time profiles of both He emission lines. The results clearly lead to the conclusion that the metastable excited triplet He atoms are actually the species overwhelmingly produced during the recombination process in the ns laser-induced He gas plasma. These metastable He atoms are believed to serve as the major energy source for the delayed excitation of analyte atoms in ns laser-induced breakdown spectroscopy (LIBS) using He ambient gas.

  12. Fast quantification of endogenous carbohydrates in plasma using hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry.

    PubMed

    Zhu, Bangjie; Liu, Feng; Li, Xituo; Wang, Yan; Gu, Xue; Dai, Jieyu; Wang, Guiming; Cheng, Yu; Yan, Chao

    2015-01-01

    Endogenous carbohydrates in biosamples are frequently highlighted as the most differential metabolites in many metabolomics studies. A simple, fast, simultaneous quantitative method for 16 endogenous carbohydrates in plasma has been developed using hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry. In order to quantify 16 endogenous carbohydrates in plasma, various conditions, including columns, chromatographic conditions, mass spectrometry conditions, and plasma preparation methods, were investigated. Different conditions in this quantified analysis were performed and optimized. The reproducibility, precision, recovery, matrix effect, and stability of the method were verified. The results indicated that a methanol/acetonitrile (50:50, v/v) mixture could effectively and reproducibly precipitate rat plasma proteins. Cold organic solvents coupled with vortex for 1 min and incubated at -20°C for 20 min were the most optimal conditions for protein precipitation and extraction. The results, according to the linearity, recovery, precision, matrix effect, and stability, showed that the method was satisfactory in the quantification of endogenous carbohydrates in rat plasma. The quantified analysis of endogenous carbohydrates in rat plasma performed excellently in terms of sensitivity, high throughput, and simple sample preparation, which met the requirement of quantification in specific expanded metabolomic studies after the global metabolic profiling research.

  13. Parametric Excitations of Fast Plasma Waves by Counter-propagating Laser Beams

    SciTech Connect

    G. Shvets; N.J. Fisch

    2001-03-19

    Short- and long-wavelength plasma waves can become strongly coupled in the presence of two counter-propagating laser pump pulses detuned by twice the cold plasma frequency. What makes this four-wave interaction important is that the growth rate of the plasma waves occurs much faster than in the more obvious co-propagating geometry.

  14. Effects of corn type and fasting time before slaughter on growth and plasma index in weaning pigs.

    PubMed

    Yang, C; He, J; Chen, D W; Yu, B; Yu, J; Mao, X B; Yang, K Y; Yuan, Z C

    2016-01-01

    A 2 × 2 factorial experiment was conducted to evaluate the effects of dietary corn type (waxy corn [WC] vs. nonwaxy corn [NC]) and fasting period (2 h vs. 12-16 h) before slaughter on growth and plasma index in weaning pigs. Twenty-four crossbred barrows (8.26 ± 0.47 kg) were allotted to 4 treatments with 6 replications of 1 pig per replicate metabolism cage. Waxy corn contained less fat, a lower amylase:amylopectin ratio, more CP, and more starch than NC. Pigs fed the WC diet had lower jejunum digesta pH compared with those fed the NC diet ( < 0.05). Maltase activity in the jejunum and ileum mucosa ( < 0.01), sucrose activity in the ileum mucosa ( < 0.01), and amylase activity in the pancreas and jejunum digesta ( < 0.05) were increased in pigs fed the WC diet relative to those fed the NC diet. But the total tract apparent digestibility (TTAD) of starch and CP was lower for the WC group ( < 0.05). Ingestion of the NC diet resulted in higher ( < 0.05) ADG and ADFI in the second week but did not affect ADG ( = 0.091) and the feed:gain ratio (F:G; = 0.077) during the whole experiment period. The plasma glucose ( < 0.01) concentration was higher and high-density lipoprotein cholesterol (HDL-C; < 0.01) concentrations was lower in the hepatic portal vein in pigs fed the WC diet relative to those fed the NC diet. Fasting 2 h before slaughter decreased the jejunum and ileum digesta pH compared with the 12-h fasting group ( < 0.01). Villus height increased in the duodenum ( < 0.01) and jejunum ( < 0.05) and the villus height:crypt depth ratio increased in the duodenum ( < 0.05) of pigs after shortening the fasting period before slaughter. Shortening the fasting time before slaughter resulted in higher plasma glucose ( < 0.05) concentrations and a higher HDL-C:low-density lipoprotein cholesterol (LDL-C) ratio ( < 0.05) whereas the LDL-C ( < 0.05) concentrations were reduced in the hepatic portal vein. The results of this experiment indicate that although the production

  15. Modeling of fast neutral-beam-generated ions and rotation effects on RWM stability in DIII-D plasmas

    SciTech Connect

    Turco, Francesca; Turnbull, Alan D.; Hanson, Jeremy M.; Navratil, Gerald A.

    2015-10-15

    Here, validation results for the MARS-K code for DIII-D equilibria, predict that the absence of fast Neutral Beam (NB) generated ions leads to a plasma response ~40–60% higher than in NB-sustained H-mode plasmas when the no-wall βN limit is reached. In a βN scan, the MARS-K model with thermal and fast-ions, reproduces the experimental measurements above the no-wall limit, except at the highest βN where the phase of the plasma response is overestimated. The dependencies extrapolate unfavorably to machines such as ITER with smaller fast ion fractions since elevated responses in the absence of fast ions indicate the potential onset of a resistive wall mode (RWM). The model was also tested for the effects of rotation at high βN, and recovers the measured response even when fast-ions are neglected, reversing the effect found in lower βN cases, but consistent with the higher βN results above the no-wall limit. The agreement in the response amplitude and phase for the rotation scan is not as good, and additional work will be needed to reproduce the experimental trends. In the case of current-driven instabilities, the magnetohydrodynamic spectroscopy system used to measure the plasma response reacts differently from that for pressure driven instabilities: the response amplitude remains low up to ~93% of the current limit, showing an abrupt increase only in the last ~5% of the current ramp. This makes it much less effective as a diagnostic for the approach to an ideal limit. However, the mode structure of the current driven RWM extends radially inwards, consistent with that in the pressure driven case for plasmas with qedge~2. This suggests that previously developed RWM feedback techniques together with the additional optimizations that enabled qedge~2 operation, can be applied to control of both current-driven and pressure-driven modes at high βN.

  16. Modeling of fast neutral-beam-generated ions and rotation effects on RWM stability in DIII-D plasmas

    DOE PAGES

    Turco, Francesca; Turnbull, Alan D.; Hanson, Jeremy M.; ...

    2015-10-15

    Here, validation results for the MARS-K code for DIII-D equilibria, predict that the absence of fast Neutral Beam (NB) generated ions leads to a plasma response ~40–60% higher than in NB-sustained H-mode plasmas when the no-wall βN limit is reached. In a βN scan, the MARS-K model with thermal and fast-ions, reproduces the experimental measurements above the no-wall limit, except at the highest βN where the phase of the plasma response is overestimated. The dependencies extrapolate unfavorably to machines such as ITER with smaller fast ion fractions since elevated responses in the absence of fast ions indicate the potential onsetmore » of a resistive wall mode (RWM). The model was also tested for the effects of rotation at high βN, and recovers the measured response even when fast-ions are neglected, reversing the effect found in lower βN cases, but consistent with the higher βN results above the no-wall limit. The agreement in the response amplitude and phase for the rotation scan is not as good, and additional work will be needed to reproduce the experimental trends. In the case of current-driven instabilities, the magnetohydrodynamic spectroscopy system used to measure the plasma response reacts differently from that for pressure driven instabilities: the response amplitude remains low up to ~93% of the current limit, showing an abrupt increase only in the last ~5% of the current ramp. This makes it much less effective as a diagnostic for the approach to an ideal limit. However, the mode structure of the current driven RWM extends radially inwards, consistent with that in the pressure driven case for plasmas with qedge~2. This suggests that previously developed RWM feedback techniques together with the additional optimizations that enabled qedge~2 operation, can be applied to control of both current-driven and pressure-driven modes at high βN.« less

  17. Fast ion motion in the plasma part of a stellarator-mirror fission-fusion hybrid

    NASA Astrophysics Data System (ADS)

    Moiseenko, V. E.; Nemov, V. V.; Ågren, O.; Kasilov, S. V.; Garkusha, I. E.

    2016-06-01

    Recent developments of a stellarator-mirror (SM) fission-fusion hybrid concept are reviewed. The hybrid consists of a fusion neutron source and a powerful sub-critical fast fission reactor core. The aim is transmutation of spent nuclear fuel and safe fission energy production. In its fusion part, a stellarator-type system with an embedded magnetic mirror is used. The stellarator confines deuterium plasma with moderate temperature, 1-2 keV. In the magnetic mirror, a hot component of sloshing tritium ions is trapped. There, the fusion neutrons are generated. A candidate for a combined SM system is a DRACON magnetic trap. A basic idea behind an SM device is to maintain local neutron production in a mirror part, but at the same time eliminate the end losses by using a toroidal device. A possible drawback is that the stellarator part can introduce collision-free radial drift losses, which is the main topic for this study. For high energy ions of tritium with an energy of 70 keV, comparative computations of collisionless losses in the rectilinear part of a specific design of the DRACON type trap are carried out. Two versions of the trap are considered with different lengths of the rectilinear sections. Also the total number of current-carrying rings in the magnetic system is varied. The results predict that high energy ions from neutral beam injection can be satisfactorily confined in the mirror part during 0.1-1 s. The Uragan-2M experimental device is used to check key points of the SM concept. The magnetic configuration of a stellarator with an embedded magnetic mirror is arranged in this device by switching off one toroidal coil. The motion of particles magnetically trapped in the embedded mirror is analyzed numerically with use of motional invariants. It is found that without radial electric field particles quickly drift out of the SM, even if the particles initially are located on a nested magnetic surface. We will show that a weak radial electric field, which

  18. [Burden of disease attributable to high fasting plasma glucose in 1990 and 2013 in China].

    PubMed

    Zhao, Y F; Wang, Z Q; Yang, J; Li, Y C; Yin, P; You, J L; Zhou, M G

    2016-09-06

    Objective: To analyze the burden of disease attributed to high fasting plasma glucose(FPG)in China in 1990 and 2013. Methods: The analysis used data obtained from the 2013 Global Burden of Diseases Study and examined deaths, death rate, disability-adjusted life years(DALY), years lived with disability(YLD)and years of life lost(YLL)attributed to high FPG in 1990 and 2013 in China(not including Taiwan, China). An average world population age-structure for the period 2000- 2025 was adopted to calculate age-standardized rates. Results: In 2013, the number of deaths attributed to high FPG in China increased to 621.9 thousand from 320.3 thousand in 1990. From 1990- 2013, the age-standardized death rate attributable to high FPG increased from 45.69/100 000 to 48.64/100 000. DALYs caused by high FPG increased to 20.389 1 million in 2013 from 10.648 3 million in 1990. In 2013, high FPG caused 8.751 5 million YLD and 11.637 6 million YLL, and the percentage of YLL in DALY decreased to 57.1% in 2013 from 68.7% in 1990. Compared with 1990, the age-standardized DALY rate attributed to high FPG increased by 10.81%. In 2013, the top three provinces with the highest burden of disease attributed to high FPG were Xinjiang, Jilin and Liaoning provinces, with standardized death rates of 83.38, 74.01 and 68.64/100 000, respectively, and the standardized DALY rate was 2 217.96, 2 001.84 and 1 837.79/100 000 in the three provinces, respectively. Conclusion: Compared with 1990, the burden of disease attributed to high FPG in 2013 increased substantially in China, in particular the burden of attributed YLD. However, the burden of YLL attributed to high FPG has decreased modestly. The burden of disease caused by high FPG shows variation among different provinces in China.

  19. Fast Plasma Investigation for MMS: Simulation of the Burst Triggering System

    NASA Technical Reports Server (NTRS)

    Barrie, A. C.; Dorelli, J. C.; Winkert, G. E.; Lobell, J. V.; Holland, M. P.; Adrian, M. L.; Pollock, C. J.

    2011-01-01

    The Magnetospheric Multiscale (MMS) mission will study small-scale reconnection structures and their rapid motions from closely spaced platforms using instruments capable of high angular, energy, and time resolution measurements. To meet these requirements, the Fast Plasma Instrument (FPI) consists of eight (8) identical half top-hat electron sensors and eight (8) identical ion sensors and an Instrument Data Processing Unit (IDPU). The sensors (electron or ion) are grouped into pairs whose 6 degree x 180 degree fields-of-view (FOV) are set 90 degrees apart. Each sensor is equipped with electrostatic aperture steering to allow the sensor to scan a 45 degree x 180 degree fan about the its nominal viewing (0 deflection) direction. Each pair of sensors, known as the Dual Electron Spectrometer (DES) and the Dual Ion Spectrometer (DIS), occupies a quadrant on the MMS spacecraft and the combination of the eight electron/ion sensors, employing aperture steering, image the full-sky every 30-ms (electrons) and 150-ms (ions), respectively. To probe the diffusion regions of reconnection, the highest temporal/spatial resolution mode of FPI results in the DES complement of a given spacecraft generating 6.5-Mb (raised dot) per second of electron data while the DIS generates 1.1-Mb (raised dot) per second of ion data yielding an FPI total data rate of 6.6-Mb (raised dot) per second. The FPI electron/ion data is collected by the IDPU then transmitted to the Central Data Instrument Processor (CIDP) on the spacecraft for science interest ranking. Only data sequences that contain the greatest amount of temporal/spatial structure will be intelligently down-linked by the spacecraft. This requires a data ranking process known as the burst trigger system. The burst trigger system uses pseudo physical quantities to approximate the local plasma environments. As each pseudo quantity will have a different value, a set of two scaling factors is employed for each pseudo term. These pseudo

  20. Rydberg gas theory of a glow discharge plasma: I. Application to the electrical behaviour of a fast flowing glow discharge plasma.

    PubMed

    Mason, Rod S; Mitchell, David J; Dickinson, Paul M

    2010-04-21

    Current-voltage (I-V) curves have been measured, independent of the main discharge, for electricity passing through the steady state fast flowing 'afterglow' plasma of a low power dc glow discharge in Ar. Voltage profiles along the axial line of conduction have been mapped using fixed probes and potentiometry, and the mass spectra of cations emerging from the downstream sampling Cone, also acting as a probe anode, were recorded simultaneously. Floating double probe experiments were also carried out. The electrical behavior is consistent with the well established I-V characteristics of such discharges, but does not comply with classical plasma theory predictions. The plasma decays along the line of conduction, with a lifetime of approximately 1 ms, despite carrying a steady state current, and its potential is below that of the large surface area anode voltage; a situation which cannot exist in the presence of a conventional free ion-electron plasma, unless the electron temperature is super cold. Currents, large by comparison with the main discharge current, and independent of it, are induced to flow through the downstream plasma, from the Anode (acting as a cathode) to the anodic ion exit Cone, induced by electron impact ionisation at the anode, but without necessarily increasing the plasma density. It appears to be conducted by direct charge transfer between a part of the anode surface (acting as cathode to the auxiliary circuit) and the plasma, without secondary electron emission or heating, which suggests the direct involvement of Rydberg atom intermediates. The reaction energy defect (= the work function of the electrode surface) fits with the plasma potential threshold observed for the cathodic reaction to occur. A true free ion-electron plasma is readily detected by the observation of cations at the anode surface, when induced at the downstream anode, at high bias voltages, by the electron impact ionisation in the boundary region. In contrast to the classical

  1. Variations of High-Energy Ions during Fast Plasma Flows and Dipolarization in the Plasma Sheet: Comparison Among Different Ion Species

    NASA Astrophysics Data System (ADS)

    Ohtani, S.; Nose, M.; Miyashita, Y.; Lui, A.

    2014-12-01

    We investigate the responses of different ion species (H+, He+, He++, and O+) to fast plasma flows and local dipolarization in the plasma sheet in terms of energy density. We use energetic (9-210 keV) ion composition measurements made by the Geotail satellite at r = 10~31 RE. The results are summarized as follows: (1) whereas the O+-to-H+ ratio decreases with earthward flow velocity, it increases with tailward flow velocity with Vx dependence steeper for perpendicular flows than for parallel flows; (2) for fast earthward flows, the energy density of each ion species increases without any clear preference for heavy ions; (3) for fast tailward flows the ion energy density increases initially, then it decreases to below pre-flow levels except for O+; (4) the O+-to-H+ ratio does not increase through local dipolarization irrespective of dipolarization amplitude, background BZ, X distance, and VX; (5) in general, the H+ and He++ ions behave similarly. Result (1) can be attributed to radial transport along with the earthward increase of the background O+-to-H+ ratio. Results (2) and (4) indicate that ion energization associated with local dipolarization is not mass-dependent possibly because in the energy range of our interest the ions are not magnetized irrespective of species. In the tailward outflow region of reconnection, where the plasma sheet becomes thinner, the H+ ions escape along the field line more easily than the O+ ions, which possibly explains result (3). Result (5) suggests that the solar wind is the primary source of the high-energy H+ ions.

  2. Decreased expression of adipose CD36 and FATP1 are associated with increased plasma nonesterified fatty acids during prolonged fasting in northern elephant seal pups (Mirounga angustirostris)

    USDA-ARS?s Scientific Manuscript database

    The northern elephant seal undergoes a 2-3 month post-weaning fast during which it depends primarily on the oxidation of fatty acids to meet its energetic demands. The concentration of plasma free fatty acids (FFA) increases and is associated with the development of insulin resistance in late-fasted...

  3. Laser-driven cylindrical compression of targets for fast electron transport study in warm and dense plasmas

    SciTech Connect

    Vauzour, B.; Nicolaie, Ph.; Dorchies, F.; Fourment, C.; Hulin, S.; Regan, C.; Ribeyre, X.; Schurtz, G.; Santos, J. J.; Perez, F.; Baton, S. D.; Brambrink, E.; Volpe, L.; Batani, D.; Jafer, R.; Lancaster, K.; Galimberti, M.; Heathcote, R.; Beg, F. N.; Chawla, S.

    2011-04-15

    Fast ignition requires a precise knowledge of fast electron propagation in a dense hydrogen plasma. In this context, a dedicated HiPER (High Power laser Energy Research) experiment was performed on the VULCAN laser facility where the propagation of relativistic electron beams through cylindrically compressed plastic targets was studied. In this paper, we characterize the plasma parameters such as temperature and density during the compression of cylindrical polyimide shells filled with CH foams at three different initial densities. X-ray and proton radiography were used to measure the cylinder radius at different stages of the compression. By comparing both diagnostics results with 2D hydrodynamic simulations, we could infer densities from 2 to 11 g/cm{sup 3} and temperatures from 30 to 120 eV at maximum compression at the center of targets. According to the initial foam density, kinetic, coupled (sometimes degenerated) plasmas were obtained. The temporal and spatial evolution of the resulting areal densities and electrical conductivities allow for testing electron transport in a wide range of configurations.

  4. CELLULOSE SYNTHASE INTERACTIVE1 Is Required for Fast Recycling of Cellulose Synthase Complexes to the Plasma Membrane in Arabidopsis

    PubMed Central

    Lei, Lei; Bashline, Logan; Li, Shundai

    2015-01-01

    Plants are constantly subjected to various biotic and abiotic stresses and have evolved complex strategies to cope with these stresses. For example, plant cells endocytose plasma membrane material under stress and subsequently recycle it back when the stress conditions are relieved. Cellulose biosynthesis is a tightly regulated process that is performed by plasma membrane-localized cellulose synthase (CESA) complexes (CSCs). However, the regulatory mechanism of cellulose biosynthesis under abiotic stress has not been well explored. In this study, we show that small CESA compartments (SmaCCs) or microtubule-associated cellulose synthase compartments (MASCs) are critical for fast recovery of CSCs to the plasma membrane after stress is relieved in Arabidopsis thaliana. This SmaCC/MASC-mediated fast recovery of CSCs is dependent on CELLULOSE SYNTHASE INTERACTIVE1 (CSI1), a protein previously known to represent the link between CSCs and cortical microtubules. Independently, AP2M, a core component in clathrin-mediated endocytosis, plays a role in the formation of SmaCCs/MASCs. Together, our study establishes a model in which CSI1-dependent SmaCCs/MASCs are formed through a process that involves endocytosis, which represents an important mechanism for plants to quickly regulate cellulose synthesis under abiotic stress. PMID:26443667

  5. CELLULOSE SYNTHASE INTERACTIVE1 Is Required for Fast Recycling of Cellulose Synthase Complexes to the Plasma Membrane in Arabidopsis

    SciTech Connect

    Lei, Lei; Singh, Abhishek; Bashline, Logan; Li, Shundai; Yingling, Yaroslava G.; Gu, Ying

    2015-10-06

    Plants are constantly subjected to various biotic and abiotic stresses and have evolved complex strategies to cope with these stresses. For example, plant cells endocytose plasma membrane material under stress and subsequently recycle it back when the stress conditions are relieved. Cellulose biosynthesis is a tightly regulated process that is performed by plasma membrane-localized cellulose synthase (CESA) complexes (CSCs). However, the regulatory mechanism of cellulose biosynthesis under abiotic stress has not been well explored. In this study, we show that small CESA compartments (SmaCCs) or microtubule-associated cellulose synthase compartments (MASCs) are critical for fast recovery of CSCs to the plasma membrane after stress is relieved in Arabidopsis thaliana. This SmaCC/MASC-mediated fast recovery of CSCs is dependent on CELLULOSE SYNTHASE INTERACTIVE1 (CSI1), a protein previously known to represent the link between CSCs and cortical microtubules. Independently, AP2M, a core component in clathrin-mediated endocytosis, plays a role in the formation of SmaCCs/MASCs. Together, our study establishes a model in which CSI1-dependent SmaCCs/MASCs are formed through a process that involves endocytosis, which represents an important mechanism for plants to quickly regulate cellulose synthesis under abiotic stress.

  6. Activated protein C plasma levels in the fasting and postprandial states among patients with previous unprovoked venous thromboembolism.

    PubMed

    Hansen, John-Bjarne; Fernández, José A; Borch, Knut H; Griffin, John H; Brox, Jan H; Braekkan, Sigrid K

    2012-04-01

    The protein C anticoagulant system is of major importance in the regulation of thrombotic risk, but it is not known whether low plasma levels of activated protein C (APC) in vivo reflect a compromised anticoagulant situation with increased thrombotic risk. Previous studies have reported low, normal or increased plasma APC levels in unselected patients with venous thromboembolism (VTE). We performed a population-based, case-control study in patients with a previous history of unprovoked VTE and subjected the participants to a standard fat tolerance test (1g fat/kg body weight) in order to promote physiological coagulation activation. VTE patients had higher BMI (28.3 ± 4.4 kg/m(2) versus 26.3 ± 3.9 kg/m(2), p=0.045) and greater waist circumference (98.2 ± 12.5 cm versus 93.4 ± 13.4 cm, p=0.041) than age and sex matched controls. APC levels were equal in fasting plasma (3.00 ± 0.74 ng/ml and 2.99 ± 0.60 ng/ml, p=0.66) but higher in postprandial plasma (3.18 ± 0.57 ng/ml and 2.81 ± 0.38 ng/ml, p=0.008) collected from VTE patients and controls, respectively. Endogenous thrombin generation in plasma following a standardized meal, assessed by thrombin-antithrombin complex (TAT), increased similarly in both groups, whereas APC increased only among the VTE patients during the postprandial state. Plasma levels of APC increased linearly with TAT in the postprandial state (p for linear trend=0.012). Our findings fail to support the hypothesis that low APC levels are linked to increased thrombotic risk in unprovoked VTE, and they suggest that plasma APC is a biomarker of thrombin generation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Activated Protein C Plasma Levels in the Fasting and Postprandial States among Patients with Previous Unprovoked Venous Thromboembolism

    PubMed Central

    Hansen, John-Bjarne; Fernández, José A.; Borch, Knut H.; Griffin, John H.; Brox, Jan H.; Braekkan, Sigrid K.

    2012-01-01

    Introduction The protein C anticoagulant system is of major importance in the regulation of thrombotic risk, but it is not known whether low plasma levels of activated protein C (APC) in vivo reflect a compromised anticoagulant situation with increased thrombotic risk. Previous studies have reported low, normal or increased plasma APC levels in unselected patients with venous thromboembolism (VTE). Materials and Methods We performed a population-based, case-control study in patients with a previous history of unprovoked VTE and subjected the participants to a standard fat tolerance test (1 g fat/kg body weight) in order to promote physiological coagulation activation. Results: VTE patients had higher BMI (28.3±4.4 kg/m2 versus 26.3±3.9 kg/m2, p=0.045) and greater waist circumference (98.2±12.5 cm versus 93.4±13.4 cm, p=0.041) than age and sex matched controls. APC levels were equal in fasting plasma (3.00±0.74 ng/ml and 2.99±0.60 ng/ml, p=0.66) but higher in postprandial plasma (3.18±0.57 ng/ml and 2.81±0.38 ng/ml, p=0.008) collected from VTE patients and controls, respectively. Endogenous thrombin generation in plasma following a standardized meal, assessed by thrombin-antithrombin complex (TAT), increased similarly in both groups, whereas APC increased only among the VTE patients during the postprandial state. Plasma levels of APC increased linearly with TAT in the postprandial state (p for linear trend=0.012). Conclusions Our findings fail to support the hypothesis that low APC levels are linked to increased thrombotic risk in unprovoked VTE, and they suggest that plasma APC is a biomarker of thrombin generation. PMID:21777953

  8. Fast low-temperature plasma reduction of monolayer graphene oxide at atmospheric pressure

    NASA Astrophysics Data System (ADS)

    Bodik, Michal; Zahoranova, Anna; Micusik, Matej; Bugarova, Nikola; Spitalsky, Zdenko; Omastova, Maria; Majkova, Eva; Jergel, Matej; Siffalovic, Peter

    2017-04-01

    We report on an ultrafast plasma-based graphene oxide reduction method superior to conventional vacuum thermal annealing and/or chemical reduction. The method is based on the effect of non-equilibrium atmospheric-pressure plasma generated by the diffuse coplanar surface barrier discharge in proximity of the graphene oxide layer. As the reduction time is in the order of seconds, the presented method is applicable to the large-scale production of reduced graphene oxide layers. The short reduction times are achieved by the high-volume power density of plasma, which is of the order of 100 W cm-3. Monolayers of graphene oxide on silicon substrate were prepared by a modified Langmuir-Schaefer method and the efficient and rapid reduction by methane and/or hydrogen plasma was demonstrated. The best results were obtained for the graphene oxide reduction in hydrogen plasma, as verified by x-ray photoelectron spectroscopy and Raman spectroscopy.

  9. Fast low-temperature plasma reduction of monolayer graphene oxide at atmospheric pressure.

    PubMed

    Bodik, Michal; Zahoranova, Anna; Micusik, Matej; Bugarova, Nikola; Spitalsky, Zdenko; Omastova, Maria; Majkova, Eva; Jergel, Matej; Siffalovic, Peter

    2017-04-07

    We report on an ultrafast plasma-based graphene oxide reduction method superior to conventional vacuum thermal annealing and/or chemical reduction. The method is based on the effect of non-equilibrium atmospheric-pressure plasma generated by the diffuse coplanar surface barrier discharge in proximity of the graphene oxide layer. As the reduction time is in the order of seconds, the presented method is applicable to the large-scale production of reduced graphene oxide layers. The short reduction times are achieved by the high-volume power density of plasma, which is of the order of 100 W cm(-3). Monolayers of graphene oxide on silicon substrate were prepared by a modified Langmuir-Schaefer method and the efficient and rapid reduction by methane and/or hydrogen plasma was demonstrated. The best results were obtained for the graphene oxide reduction in hydrogen plasma, as verified by x-ray photoelectron spectroscopy and Raman spectroscopy.

  10. Genome-wide association meta-analysis identifies novel variants associated with fasting plasma glucose in East Asians.

    PubMed

    Hwang, Joo-Yeon; Sim, Xueling; Wu, Ying; Liang, Jun; Tabara, Yasuharu; Hu, Cheng; Hara, Kazuo; Tam, Claudia H T; Cai, Qiuyin; Zhao, Qi; Jee, Sunha; Takeuchi, Fumihiko; Go, Min Jin; Ong, Rick Twee Hee; Ohkubo, Takayoshi; Kim, Young Jin; Zhang, Rong; Yamauchi, Toshimasa; So, Wing Yee; Long, Jirong; Gu, Dongfeng; Lee, Nanette R; Kim, Soriul; Katsuya, Tomohiro; Oh, Ji Hee; Liu, Jianjun; Umemura, Satoshi; Kim, Yeon-Jung; Jiang, Feng; Maeda, Shiro; Chan, Juliana C N; Lu, Wei; Hixson, James E; Adair, Linda S; Jung, Keum Ji; Nabika, Toru; Bae, Jae-Bum; Lee, Mi Hee; Seielstad, Mark; Young, Terri L; Teo, Yik Ying; Kita, Yoshikuni; Takashima, Naoyuki; Osawa, Haruhiko; Lee, So-Hyun; Shin, Min-Ho; Shin, Dong Hoon; Choi, Bo Youl; Shi, Jiajun; Gao, Yu-Tang; Xiang, Yong-Bing; Zheng, Wei; Kato, Norihiro; Yoon, Miwuk; He, Jiang; Shu, Xiao Ou; Ma, Ronald C W; Kadowaki, Takashi; Jia, Weiping; Miki, Tetsuro; Qi, Lu; Tai, E Shyong; Mohlke, Karen L; Han, Bok-Ghee; Cho, Yoon Shin; Kim, Bong-Jo

    2015-01-01

    Fasting plasma glucose (FPG) has been recognized as an important indicator for the overall glycemic state preceding the onset of metabolic diseases. So far, most indentified genome-wide association loci for FPG were derived from populations with European ancestry, with a few exceptions. To extend a thorough catalog for FPG loci, we conducted meta-analyses of 13 genome-wide association studies in up to 24,740 nondiabetic subjects with East Asian ancestry. Follow-up replication analyses in up to an additional 21,345 participants identified three new FPG loci reaching genome-wide significance in or near PDK1-RAPGEF4, KANK1, and IGF1R. Our results could provide additional insight into the genetic variation implicated in fasting glucose regulation. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  11. Genome-Wide Association Meta-analysis Identifies Novel Variants Associated With Fasting Plasma Glucose in East Asians

    PubMed Central

    Hwang, Joo-Yeon; Sim, Xueling; Wu, Ying; Liang, Jun; Tabara, Yasuharu; Hu, Cheng; Hara, Kazuo; Tam, Claudia H.T.; Cai, Qiuyin; Zhao, Qi; Jee, Sunha; Takeuchi, Fumihiko; Go, Min Jin; Ong, Rick Twee Hee; Ohkubo, Takayoshi; Kim, Young Jin; Zhang, Rong; Yamauchi, Toshimasa; So, Wing Yee; Long, Jirong; Gu, Dongfeng; Lee, Nanette R.; Kim, Soriul; Katsuya, Tomohiro; Oh, Ji Hee; Liu, Jianjun; Umemura, Satoshi; Kim, Yeon-Jung; Jiang, Feng; Maeda, Shiro; Chan, Juliana C.N.; Lu, Wei; Hixson, James E.; Adair, Linda S.; Jung, Keum Ji; Nabika, Toru; Bae, Jae-Bum; Lee, Mi Hee; Seielstad, Mark; Young, Terri L.; Teo, Yik Ying; Kita, Yoshikuni; Takashima, Naoyuki; Osawa, Haruhiko; Lee, So-Hyun; Shin, Min-Ho; Shin, Dong Hoon; Choi, Bo Youl; Shi, Jiajun; Gao, Yu-Tang; Xiang, Yong-Bing; Zheng, Wei; Kato, Norihiro; Yoon, Miwuk; He, Jiang; Shu, Xiao Ou; Ma, Ronald C.W.; Kadowaki, Takashi; Jia, Weiping; Miki, Tetsuro; Qi, Lu; Tai, E Shyong; Mohlke, Karen L.

    2015-01-01

    Fasting plasma glucose (FPG) has been recognized as an important indicator for the overall glycemic state preceding the onset of metabolic diseases. So far, most indentified genome-wide association loci for FPG were derived from populations with European ancestry, with a few exceptions. To extend a thorough catalog for FPG loci, we conducted meta-analyses of 13 genome-wide association studies in up to 24,740 nondiabetic subjects with East Asian ancestry. Follow-up replication analyses in up to an additional 21,345 participants identified three new FPG loci reaching genome-wide significance in or near PDK1-RAPGEF4, KANK1, and IGF1R. Our results could provide additional insight into the genetic variation implicated in fasting glucose regulation. PMID:25187374

  12. Current drive with combined electron cyclotron wave and high harmonic fast wave in tokamak plasmas

    NASA Astrophysics Data System (ADS)

    Li, J. C.; Gong, X. Y.; Dong, J. Q.; Wang, J.; Zhang, N.; Zheng, P. W.; Yin, C. Y.

    2016-12-01

    The current driven by combined electron cyclotron wave (ECW) and high harmonic fast wave is investigated using the GENRAY/CQL3D package. It is shown that no significant synergetic current is found in a range of cases with a combined ECW and fast wave (FW). This result is consistent with a previous study [Harvey et al., in Proceedings of IAEA TCM on Fast Wave Current Drive in Reactor Scale Tokamaks (Synergy and Complimentarily with LHCD and ECRH), Arles, France, IAEA, Vienna, 1991]. However, a positive synergy effect does appear with the FW in the lower hybrid range of frequencies. This positive synergy effect can be explained using a picture of the electron distribution function induced by the ECW and a very high harmonic fast wave (helicon). The dependence of the synergy effect on the radial position of the power deposition, the wave power, the wave frequency, and the parallel refractive index is also analyzed, both numerically and physically.

  13. Effects of fast halogen and plasma arc curing lights on the surface hardness of orthodontic adhesives for lingual retainers.

    PubMed

    Uşümez, Serdar; Büyükyilmaz, Tamer; Karaman, Ali Ihya

    2003-06-01

    The aims of this study were to (1) identify the optimum cure times of 2 different lingual retainer adhesives with a conventional halogen, a fast halogen, and a plasma arc light by measuring Vickers surface hardness, and (2) determine whether different lights produce similar surface hardness values for the same adhesive resin material. The investigated plasma arc curing unit was the PowerPac (American Dental Technologies, Corpus Christi, Tex), and the fast halogen unit was the Optilux 501 (Kerr, Orange, Calif). A conventional curing unit, the Ortholux XT (3M Dental Products, St. Paul, Minn) was used as the control. Two orthodontic lingual retainer adhesives were used: Transbond Lingual Retainer (3M Unitek, Monrovia, Calif) and Light Cure Retainer (Reliance Orthodontic Products, Itasca, Ill). Concise (3M Dental Products) and diluted Concise were used as controls. Transbond Lingual Retainer was polymerized by the PowerPac light in 6 seconds, by the Optilux in 10 seconds, and by the conventional halogen light in 20 seconds. The minimum curing times for Light Cure Retainer adhesive were 15 seconds for PowerPac, 10 seconds for Optilux, and 40 seconds for conventional halogen. Surface hardness values for each resin did not differ significantly with different curing units. However, different adhesives demonstrated significantly different surface hardness values. Final Vickers surface hardness values (averaged across curing units) of Transbond Lingual Retainer, Concise, diluted Concise, and Light Cure Retainer were 62.8, 52.4, 46.0, and 40.4, respectively. Plasma arc or fast halogen units polymerize resin composite adhesive in much shorter times than do conventional curing units, without a significant loss in surface hardness. Therefore, these units are suggested for clinical use to save chairside time.

  14. Quantification of the nonenzymatic fast and slow TRAP in a postaddition assay in human seminal plasma and the antioxidant contributions of various seminal compounds.

    PubMed

    Rhemrev, J P; van Overveld, F W; Haenen, G R; Teerlink, T; Bast, A; Vermeiden, J P

    2000-01-01

    Total radical-trapping antioxidant potential (TRAP) measurements of human seminal plasma (N = 25) were performed by using a post-addition assay based on trapping 2,2' Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radicals. This method enables the antioxidant capacity of human seminal plasma and its constituents to be quantified. The standard procedure consisted of determination of the Trolox equivalent antioxidant capacity (TEAC) after incubating the test sample in the ABTS radical solution for 10 seconds (fast TRAP) and 300 s (total TRAP). Interestingly, seminal plasma showed a fast TRAP and a high slow TRAP (Total TRAP - Fast TRAP). The final total TRAP of seminal plasma is about 10 times higher than that of blood plasma. Various components of seminal plasma contribute to its fast TRAP; 37% can be attributed to vitamin C, uric acid, and tyrosine; proteins and polyphenolic compounds contribute a further 57%. In contrast, the slow TRAP was attributed to vitamin C (1%), uric acid (2%), and tyrosine (15%) and to proteins and polyphenolic compounds (33%). It was not possible to account for the remaining 49%. Neither known putative antioxidants, such as spermine, pyruvate, and taurine, nor other seminal compounds, such as carnitine, sialic acid, fructose, spermidine, glycerophosphorylcholine, and hyaluronic acid, contributed to any significant radical-trapping activity at a standard concentration of 1 mM. Of the amino acids, only tyrosine possessed a slow TRAP, and it is present at a high concentration in seminal plasma. Glutathione and hypotaurine show high fast and slow TRAPs, respectively. However, because of their low concentration in seminal plasma, their contribution to the TRAP is negligible. In conclusion, seminal plasma possesses a high antioxidant buffer capacity that protects spermatozoa from oxidative stress. Moreover, these findings suggest that the fast and slow TRAPs may have an important role as infertility markers and treatment targets in

  15. Physical processes taking place in dense plasma focus devices at the interaction of hot plasma and fast ion streams with materials under test

    NASA Astrophysics Data System (ADS)

    Gribkov, V. A.

    2015-06-01

    The dense plasma focus (DPF) device represents a source of powerful streams of penetrating radiations (hot plasma, fast electron and ion beams, x-rays and neutrons) of ns-scale pulse durations. Power flux densities of the radiation types may reach in certain cases the values up to 1013 W cm  -  2. They are widely used at present time in more than 30 labs in the world in the field of radiation material science. Areas of their implementations are testing of the materials perspective for use in modern fusion reactors (FR) of both types, modification of surface layers with an aim of improvements their properties, production of some nanostructures on their surface, and so on. To use a DPF correctly in these applications it is important to understand the mechanisms of generation of the above-mentioned radiations, their dynamics inside and outside of the pinch and processes of interaction of these streams with targets. In this paper, the most important issues on the above matter we discuss in relation to the cumulative hot plasma stream and the beam of fast ions with illustration of experimental results obtained at four DPF devices ranged in the limits of bank energies from 1 kJ to 1 MJ. Among them mechanisms of a jet formation, a current abruption phenomenon, a super-Alfven ion beam propagation inside and outside of DPF plasma, generation of secondary plasma and formation of shock waves in plasma and inside a solid-state target, etc. Nanosecond time-resolved techniques (electric probes, laser interferometry, frame self-luminescent imaging, x-ray/neutron probes, etc) give an opportunity to investigate the above-mentioned events and to observe the process of interaction of the radiation types with targets. After irradiation, we analyzed the specimens by contemporary instrumentation: optical and scanning electron microscopy, local x-ray spectral and structure analysis, atomic force microscopy, the portable x-ray diffractometer that combines x-ray single

  16. Two Dual Ion Spectrometer Flight Units of the Fast Plasma Instrument Suite (FPI) for the Magnetospheric Multiscale Mission (MMS)

    NASA Technical Reports Server (NTRS)

    Adams, Mitzi

    2014-01-01

    Two Dual Ion Spectrometer flight units of the Fast Plasma Instrument Suite (FPI) for the Magnetospheric Multiscale Mission (MMS) have returned to MSFC for flight testing. Anticipated to begin on June 30, tests will ensue in the Low Energy Electron and Ion Facility of the Heliophysics and Planetary Science Office (ZP13), managed by Dr. Victoria Coffey of the Natural Environments Branch of the Engineering Directorate (EV44). The MMS mission consists of four identical spacecraft, whose purpose is to study magnetic reconnection in the boundary regions of Earth's magnetosphere.

  17. Staged venting of fuel cell system during rapid shutdown

    DOEpatents

    Keskula, Donald H.; Doan, Tien M.; Clingerman, Bruce J.

    2004-09-14

    A venting methodology and system for rapid shutdown of a fuel cell apparatus of the type used in a vehicle propulsion system. H.sub.2 and air flows to the fuel cell stack are slowly bypassed to the combustor upon receipt of a rapid shutdown command. The bypass occurs over a period of time (for example one to five seconds) using conveniently-sized bypass valves. Upon receipt of the rapid shutdown command, the anode inlet of the fuel cell stack is instantaneously vented to a remote vent to remove all H.sub.2 from the stack. Airflow to the cathode inlet of the fuel cell stack gradually diminishes over the bypass period, and when the airflow bypass is complete the cathode inlet is also instantaneously vented to a remote vent to eliminate pressure differentials across the stack.

  18. Staged venting of fuel cell system during rapid shutdown

    DOEpatents

    Clingerman, Bruce J.; Doan, Tien M.; Keskula, Donald H.

    2002-01-01

    A venting methodology and system for rapid shutdown of a fuel cell apparatus of the type used in a vehicle propulsion system. H.sub.2 and air flows to the fuel cell stack are slowly bypassed to the combustor upon receipt of a rapid shutdown command. The bypass occurs over a period of time (for example one to five seconds) using conveniently-sized bypass valves. Upon receipt of the rapid shutdown command, the anode inlet of the fuel cell stack is instantaneously vented to a remote vent to remove all H.sub.2 from the stack. Airflow to the cathode inlet of the fuel cell stack gradually diminishes over the bypass period, and when the airflow bypass is complete the cathode inlet is also instantaneously vented to a remote vent to eliminate pressure differentials across the stack.

  19. Fishbones in Joint European Torus plasmas with high ion-cyclotron-resonance-heated fast ions energy content

    SciTech Connect

    Nabais, F.; Borba, D.; Mantsinen, M.; Nave, M.F.F.; Sharapov, S.E.; Joint

    2005-10-01

    In Joint European Torus (JET) [P. J. Lomas, Plasma Phys. Controled Fusion 31, 1481 (1989)], discharges with ion cyclotron resonance heating only, low-density plasmas and high fast ions energy contents provided a scenario where fishbones behavior has been observed to be related with sawtooth activity: Crashes of monster sawteeth abruptly changed the type of observed fishbones from low-frequency fishbones [B. Coppi and F. Porcelli, Phys. Rev. Lett. 57, 2272 (1986)] to high-frequency fishbones [L. Chen, R. White, and M. Rosenbluth, Phys. Rev. Lett. 52, 1122 (1984)]. During periods between crashes, the type of observed fishbones gradually changed in the opposite way. Two new fishbones regimes have been observed in intermediate stages: Fishbones bursts covering both high and low frequencies and low amplitude bursts of both types occurring simultaneously. Both sawtooth and fishbones behavior have been explained using a variational formalism.

  20. Investigation of fast-electron-induced Kα x rays in laser-produced blow-off plasma.

    PubMed

    Sawada, H; Wei, M S; Chawla, S; Morace, A; Akli, K; Yabuuchi, T; Nakanii, N; Key, M H; Patel, P K; Mackinnon, A J; McLean, H S; Stephens, R B; Beg, F N

    2014-03-01

    Refluxing of fast electrons generated by high-intensity, short-pulse lasers was investigated by measuring electron-induced Kα x rays from a buried tracer layer. Using planar foils of Au/Cu/CH, the 150-J, 0.7-ps TITAN short-pulse laser was focused on the gold foil to generate fast electrons and the 3-ns, 300-J long pulse beam irradiated on the CH side to create expanding plasma as a conducting medium. By delaying the short-pulse beam timing from the long pulse laser irradiation, the plasma size was varied to change electron refluxing in the target rear. The total yields and two-dimensional images of 8.05-keV Cu-Kα x ray were recorded with an x-ray spectrometer and two monochromatic crystal imagers. The measurements show that the integrated yields decrease by a factor of 10 from refluxing to the nonrefluxing limit. Similar radial profiles of the Kα images in the rear were observed at all delays. Hybrid-particle-in-cell simulations using plasma profiles calculated by a radiation-hydrodynamic code HYDRA agree well with the measured Kα yields. The simulations suggest that conducting plasma with the size of ∼300 μm in the laser direction and ∼600 μm in the lateral direction at the density of 2 × 1020 1/cm3 is sufficiently large to prevent electrons from refluxing in the target. The parameters found in this study can be useful in designing experiments utilizing a Kα x-ray source in refluxing regime or a tracer layer in nonrefluxing regime.

  1. Investigation of fast-electron-induced Kα x rays in laser-produced blow-off plasma

    NASA Astrophysics Data System (ADS)

    Sawada, H.; Wei, M. S.; Chawla, S.; Morace, A.; Akli, K.; Yabuuchi, T.; Nakanii, N.; Key, M. H.; Patel, P. K.; Mackinnon, A. J.; McLean, H. S.; Stephens, R. B.; Beg, F. N.

    2014-03-01

    Refluxing of fast electrons generated by high-intensity, short-pulse lasers was investigated by measuring electron-induced Kα x rays from a buried tracer layer. Using planar foils of Au/Cu/CH, the 150-J, 0.7-ps TITAN short-pulse laser was focused on the gold foil to generate fast electrons and the 3-ns, 300-J long pulse beam irradiated on the CH side to create expanding plasma as a conducting medium. By delaying the short-pulse beam timing from the long pulse laser irradiation, the plasma size was varied to change electron refluxing in the target rear. The total yields and two-dimensional images of 8.05-keV Cu-Kα x ray were recorded with an x-ray spectrometer and two monochromatic crystal imagers. The measurements show that the integrated yields decrease by a factor of 10 from refluxing to the nonrefluxing limit. Similar radial profiles of the Kα images in the rear were observed at all delays. Hybrid-particle-in-cell simulations using plasma profiles calculated by a radiation-hydrodynamic code HYDRA agree well with the measured Kα yields. The simulations suggest that conducting plasma with the size of ˜300 μm in the laser direction and ˜600 μm in the lateral direction at the density of 2 × 1020 1/cm3 is sufficiently large to prevent electrons from refluxing in the target. The parameters found in this study can be useful in designing experiments utilizing a Kα x-ray source in refluxing regime or a tracer layer in nonrefluxing regime.

  2. ITER Plasma at Ion Cyclotron Frequency Domain: The Fusion Alpha Particles Diagnostics Based on the Stimulated Raman Scattering of Fast Magnetosonic Wave off High Harmonic Ion Bernstein Modes

    NASA Astrophysics Data System (ADS)

    Stefan, V. Alexander

    2014-10-01

    A novel method for alpha particle diagnostics is proposed. The theory of stimulated Raman scattering, SRS, of the fast wave and ion Bernstein mode, IBM, turbulence in multi-ion species plasmas, (Stefan University Press, La Jolla, CA, 2008). is utilized for the diagnostics of fast ions, (4)He (+2), in ITER plasmas. Nonlinear Landau damping of the IBM on fast ions near the plasma edge leads to the space-time changes in the turbulence level, (inverse alpha particle channeling). The space-time monitoring of the IBM turbulence via the SRS techniques may prove efficient for the real time study of the fast ion velocity distribution function, spatial distribution, and transport. Supported by Nikola Tesla Labs., La Jolla, CA 92037.

  3. Equation-of-State Measurement of Dense Plasmas Heated With Fast Protons

    SciTech Connect

    Dyer, G. M.; Bernstein, A. C.; Cho, B. I.; Osterholz, J.; Grigsby, W.; Dalton, A.; Ditmire, T.; Shepherd, R.; Ping, Y.; Chen, H.; Widmann, K.

    2008-07-04

    Using an ultrafast pulse of mega-electron-volt energy protons accelerated from a laser-irradiated foil, we have heated solid density aluminum plasmas to temperatures in excess of 15 eV. By measuring the temperature and the expansion rate of the heated Al plasma simultaneously and with picosecond time resolution we have found the predictions of the SESAME Livermore equation-of-state (LEOS) tables to be accurate to within 18%, in this dense plasma regime, where there have been few previous experimental measurements.

  4. Equation-of-State Measurement of Dense Plasmas Heated With Fast Protons

    NASA Astrophysics Data System (ADS)

    Dyer, G. M.; Bernstein, A. C.; Cho, B. I.; Osterholz, J.; Grigsby, W.; Dalton, A.; Shepherd, R.; Ping, Y.; Chen, H.; Widmann, K.; Ditmire, T.

    2008-07-01

    Using an ultrafast pulse of mega-electron-volt energy protons accelerated from a laser-irradiated foil, we have heated solid density aluminum plasmas to temperatures in excess of 15 eV. By measuring the temperature and the expansion rate of the heated Al plasma simultaneously and with picosecond time resolution we have found the predictions of the SESAME Livermore equation-of-state (LEOS) tables to be accurate to within 18%, in this dense plasma regime, where there have been few previous experimental measurements.

  5. Equation-of-state measurement of dense plasmas heated with fast protons.

    PubMed

    Dyer, G M; Bernstein, A C; Cho, B I; Osterholz, J; Grigsby, W; Dalton, A; Shepherd, R; Ping, Y; Chen, H; Widmann, K; Ditmire, T

    2008-07-04

    Using an ultrafast pulse of mega-electron-volt energy protons accelerated from a laser-irradiated foil, we have heated solid density aluminum plasmas to temperatures in excess of 15 eV. By measuring the temperature and the expansion rate of the heated Al plasma simultaneously and with picosecond time resolution we have found the predictions of the SESAME Livermore equation-of-state (LEOS) tables to be accurate to within 18%, in this dense plasma regime, where there have been few previous experimental measurements.

  6. The Influence of Strong Laser Fields on the Interaction between Fast B+3 Clusters and Plasmas

    NASA Astrophysics Data System (ADS)

    E, Peng; Wang, Gui-Qiu; Yao, Li; Gao, Hong; Wang, Yao-Chuan; Zhong, Hai-Yang; Liu, Wei; Yang, Kun; Sun, Min; Xu, Dian-Guo

    2013-03-01

    The influence of a high-intensity laser field on the inelastic interactions between a swift B+3 cluster ion and a plasma target is studied by means of the linearized Vlasov-Poisson theory. Excitations of the plasma are described by the classical plasma dielectric function. In the presence of the laser field, the general expressions for the induced potential in the target and the interaction force among the ions within the cluster are derived. Based on the numerical solution of the equations of motion for the constituent ions, the Coulomb explosion patterns and the cluster's energy losses are discussed for a range of laser parameters.

  7. A rotating directional probe for the measurements of fast ion losses and plasma rotation at Tokamak Experiment for Technology Oriented Research.

    PubMed

    Rack, M; Liang, Y; Jaegers, H; Assmann, J; Satheeswaran, G; Xu, Y; Pearson, J; Yang, Y; Denner, P; Zeng, L

    2013-08-01

    This work discusses a new directional probe designed for measurements of fast ion losses and the plasma rotation with a high angular resolution in magnetically confined plasmas. Directional and especially Mach probes are commonly used diagnostics for plasma flow measurements, and their applicability for the fast ion losses detection has been demonstrated. A limitation of static Mach probes is their low angular resolution. At the Tokamak Experiment for Technology Oriented Research, the angular resolution is strongly restricted by the finite number of available measurement channels. In a dynamic plasma, where instabilities can lead to local changes of the field line pitch-angle, plasma flow, or fast ion losses, a low angular resolution makes a precise data analysis difficult and reduces the quality of the measured data. The new probe design, the rotating directional probe, combines the features of early directional probes and Mach probes. It consists of two radially aligned arrays of nine Langmuir probe pins with each array facing opposite directions. During the measurement the probe head rotates along its axis to measure the ion saturation current from all directions. As a result, the rotating directional probe simultaneously provides an angular dependent plasma flow and fast ion losses measurement at different radial positions. Based on the angular dependent data, a precise determination of the current density is made. In addition, the simultaneous measurement of the ion saturation current at different radial positions allows for resolving radially varying field line pitch-angles and identifying the radial dynamic of processes like fast ion losses.

  8. Characteristics of a fast rise time power supply for a pulsed plasma reactor for chemical vapor destruction

    SciTech Connect

    Lawless, P.A.; Yamamoto, Toshiaki; Shofran, S.P.; Boss, C.B.; Nunez, C.M.; Ramsey, G.H.; Engels, R.L.

    1996-11-01

    Rotating spark gap devices for switching high-voltage direct current (dc) into a corona plasma reactor can achieve pulse rise times in the range of tens of nanoseconds. The fast rise times lead to vigorous plasma generation without sparking at instantaneous applied voltages higher than can be obtained with dc. The resulting energetic plasma is effective for destroying a variety of molecules. The spark gap circuit configuration plays an important role in the effectiveness of the plasma generation. A single-gap circuit is effective for generating moderate peak voltages, but is limited by a multiple sparking phenomenon. A double-gap circuit can achieve equal peak voltages with every spark, but with a reduced number of pulses, compared to the single gap. Both configurations have an upper voltage imposed by the changing impedance of the reactor as voltage and frequency are varied. The pulse characteristics are reported for both types of circuits. The general performance of the reactors for destruction of some compounds with both circuits is also reported.

  9. Electrostatic analyzer with a 3-D instantaneous field of view for fast measurements of plasma distribution functions in space

    NASA Astrophysics Data System (ADS)

    Morel, X.; Berthomier, M.; Berthelier, J.-J.

    2017-03-01

    We describe the concept and properties of a new electrostatic optic which aims to provide a 2π sr instantaneous field of view to characterize space plasmas. It consists of a set of concentric toroidal electrodes that form a number of independent energy-selective channels. Charged particles are deflected toward a common imaging planar detector. The full 3-D distribution function of charged particles is obtained through a single energy sweep. Angle and energy resolution of the optics depends on the number of toroidal electrodes, on their radii of curvature, on their spacing, and on the angular aperture of the channels. We present the performances, as derived from numerical simulations, of an initial implementation of this concept that would fit the need of many space plasma physics applications. The proposed instrument has 192 entrance windows corresponding to eight polar channels each with 24 azimuthal sectors. The initial version of this 3-D plasma analyzer may cover energies from a few eV up to 30 keV, typically with a channel-dependent energy resolution varying from 10% to 7%. The angular acceptance varies with the direction of the incident particle from 3° to 12°. With a total geometric factor of two sensor heads reaching 0.23 cm2 sr eV/eV, this "donut" shape analyzer has enough sensitivity to allow very fast measurements of plasma distribution functions in most terrestrial and planetary environments on three-axis stabilized as well as on spinning satellites.

  10. International Collaboration with the Shutdown of the BN-350 Reactor

    SciTech Connect

    J. A. Michelbacher; P.B. Wells; N. Organ; D. Wells

    2005-08-01

    Representatives from the United States and the United Kingdom discussed areas where collaboration on the shutdown of the BN-350 Reactor in Aktau, Kazakhstan would benefit not only Kazakhstan, but would also help to assure the successful shutdown of the reactor. A fundamental understanding of the basis for collaboration has been for each side to ‘add value’ to each of the project areas, rather than simply substitute for each other’s experience. This approach has brought distinct technical and management benefits to the decommissioning activities in Kazakhstan.

  11. Puget Sound acidity levels drop after ASARCO shutdown

    SciTech Connect

    Not Available

    1987-07-01

    The levels of acidity in Puget Sound region rainfall have decreased significantly since the shutdown of the ASARCO copper smelter in Tacoma, Washington, according to a study funded by the US Environmental Protection Agency. Results indicate that sulfate and hydrogen ion concentrations obtained from samples taken before the closure were significantly different than those collected after the shutdown. Rainwater samples collected downwind during smelter operation were also significantly different from those collected upwind. Sulfur dioxide is considered to be one of the principal contributors to acid rain. The smelter was a major source of sulfur dioxide emissions in the Puget Sound region before it shut down in March 1985.

  12. Evaluation of reactivity shutdown margin for nuclear fuel reload optimization

    SciTech Connect

    Wong, Hing-Ip; Maldonado, G.I.

    1995-12-31

    The FORMOSA-P code is a nuclear fuel management optimization package that combines simulated annealing (SA) and nodal generalized perturbation theory (GPT). Recent studies at Electricite de France (EdF-Clamart) have produced good results for power-peaking minimizations under multiple limiting control rod configurations. However, since the reactivity shutdown margin is not explicitly treated as an objective or constraint function, then any optimal loading patterns (LPs) are not guaranteed to yield an adequate shutdown margin (SDM). This study describes the implementation of the SDM calculation within a FORMOSA-P optimization. Maintaining all additional computational requirements to a minimum was a key consideration.

  13. Fast Flux Test Facility project plan. Revision 2

    SciTech Connect

    Hulvey, R.K.

    1995-11-01

    The Fast Flux Test Facility (FFTF) Transition Project Plan, Revision 2, provides changes to the major elements and project baseline for the deactivation activities necessary to transition the FFTF to a radiologically and industrially safe shutdown condition.

  14. Fast multidimensional model for the simulation of Raman amplification in plasma.

    PubMed

    Farmer, J P; Pukhov, A

    2013-12-01

    We present Leap, a simulation model for Raman amplification in plasma, combining an envelope treatment of the laser fields with an electrostatic particle-in-cell solver. The code is fully two dimensional, with the model readily extendible to three dimensions, and includes dispersive and refractive effects. Simulations carried out for Raman amplification in a plasma channel show that guiding of both the pump and the probe contribute to the evolution of the probe, resulting in a shorter, more intense pulse.

  15. LIF and fast imaging plasma jet characterization relevant for NTP biomedical applications

    NASA Astrophysics Data System (ADS)

    Riès, D.; Dilecce, G.; Robert, E.; Ambrico, P. F.; Dozias, S.; Pouvesle, J.-M.

    2014-07-01

    In the field of biomedical application, many publications report on non-thermal plasma jet potentialities for cell behaviour modifications in cancer treatment, wound healing or sterilization. However most previous plasma jet characterizations were performed when jets expend freely in air. Only recently has the influence of the targeted surface been properly considered. In this work, modifications induced by various types of targets, mimicking the biological samples, in the plasma propagation and production of hydroxyl radicals are evidenced through time-resolved intensified charge-coupled device imaging and laser-induced fluorescence (LIF) measurements. A LIF model, also specifically dedicated to estimate air and water penetration inside the jet, is used and proves to be well adapted to characterize the plasma jet under biomedical application conditions. It is shown that the plasma produced by the plasma gun counter-propagates after impinging the surface which, for the same operating parameters, leads to an increase of almost one order of magnitude in the maximum OH density (from ˜2 × 1013 cm-3 for open-air propagation to ˜1 × 1014 cm-3 for a grounded metal target). The nature of the target, especially its electrical conductivity, as well as gas flow rate and voltage amplitude are playing a key role in the production of hydroxyl radicals. The strong interplay between gas flow dynamics and plasma propagation is here confirmed by air and water distribution measurements. The need for a multi-diagnostic approach, as well as great care in setting up the in situ characterization of plasma jets, is here emphasized. Special attention must not only be paid to voltage amplitude and gas flow rate but also to the nature, humidity and conductivity of the target.

  16. Early Time, Fast Collisional Dynamics of Equilibriating Ions in a Strongly Coupled Ultracold Neutral Plasma

    NASA Astrophysics Data System (ADS)

    Strickler, Trevor; McQuillen, Patrick; Langin, Thomas; Killian, Thomas; Bannasch, Georg; Pohl, Thomas

    2014-05-01

    Collision rates in weakly-coupled plasmas are well-described by the Landau-Spitzer formula. In the regime of strong coupling, however, the formula breaks down. This has motivated much theoretical and experimental work to study collision rates in strongly-coupled plasmas. In previous work, we have demonstrated direct measurements of thermalization rates in strongly-coupled ultracold neutral plasmas (UCNPs) created by photoionizing strontium atoms in magneto-optical trap. Our technique used optical pumping to create spin ``tagged'' subpopulations of ions having skewed velocity distributions. With LIF imaging, we measured the equilibration of the skewed velocity profiles to extract ion collision rates. We are now using these techniques to explore the early time dynamics of these skewed ion velocity distributions in the first 100ns after optical pumping. Molecular dynamics simulations of strongly coupled plasmas predict deviations from the exponential decay of average skewed velocity that is expected for weakly coupled plasmas. We use probe laser pulses on the order of 30ns to measure the relaxation of the skewed velocity profiles to test the theoretical predictions. This work was supported by the United States National Science Foun- dation and Department of Energy Partnership in Basic Plasma Science and Engineering (PHY-1102516) and the Air Force Office of Scientific Research (FA9550-12-1-0267).

  17. Preliminary Evaluation of Removing Used Nuclear Fuel from Shutdown Sites

    SciTech Connect

    Maheras, Steven J.; Best, Ralph E.; Ross, Steven B.; Buxton, Kenneth A.; England, Jeffery L.; McConnell, Paul E.; Massaro, Lawrence M.; Jensen, Philip J.

    2016-09-30

    A preliminary evaluation of removing spent nuclear fuel (SNF) from 13 shutdown nuclear power plant sites was performed. At these shutdown sites the nuclear power reactors have been permanently shut down and the sites have been decommissioned or are undergoing decommissioning. The shutdown sites were Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, Zion, Crystal River, Kewaunee, San Onofre, and Vermont Yankee. The evaluation was divided into four components: Characterization of the SNF and greater-than-Class C low-level radioactive waste (GTCC waste) inventory A description of the on-site infrastructure at the shutdown sites An evaluation of the near-site transportation infrastructure and transportation experience at the shutdown sites An evaluation of the actions necessary to prepare for and remove SNF and GTCC waste. The primary sources for the inventory of SNF and GTCC waste were the U.S. Department of Energy (DOE) spent nuclear fuel inventory database, industry publications such as StoreFUEL, and government sources such as the U.S. Nuclear Regulatory Commission. The primary sources for information on the conditions of on-site infrastructure and near-site transportation infrastructure and experience included information collected during site visits, information provided by managers at the shutdown sites, Facility Interface Data Sheets compiled for DOE in 2005, Services Planning Documents prepared for DOE in 1993 and 1994, industry publications such as Radwaste Solutions, and Google Earth. State staff, State Regional Group representatives, a Tribal representative, and a Federal Railroad Administration representative have participated in nine of the shutdown site visits. Every shutdown site was found to have at least one off-site transportation mode option for removing its SNF and GTCC waste; some have multiple options. Experience removing large components during reactor decommissioning provided an

  18. Systematic review and meta-analysis reveals acutely elevated plasma cortisol following fasting but not less severe calorie restriction.

    PubMed

    Nakamura, Yuko; Walker, Brian R; Ikuta, Toshikazu

    2016-01-01

    Elevated plasma cortisol has been reported following caloric restriction, and may contribute to adverse effects including stress-induced overeating, but results from published studies are inconsistent. To clarify the effects of caloric restriction on plasma cortisol, and to assess cortisol as an indicator of stress during caloric restriction, we conducted a systematic review and meta-analysis of published studies in which cortisol was measured following caloric restriction without other manipulations in humans. We further compared effects of fasting, very low calorie diet (VLCD), and other less intense low calorie diet (LCD), as well as the duration of caloric restriction by meta-regression. Overall, caloric restriction significantly increased serum cortisol level in 13 studies (357 total participants). Fasting showed a very strong effect in increasing serum cortisol, while VLCD and LCD did not show significant increases. The meta-regression analysis showed a negative association between the serum cortisol level and the duration of caloric restriction, indicating serum cortisol is increased in the initial period of caloric restriction but decreased to the baseline level after several weeks. These results suggest that severe caloric restriction causes activation of the hypothalamic-pituitary-adrenal axis, which may be transient, but results in elevated cortisol which could mediate effects of starvation on brain and metabolic function as well as ameliorate weight loss.

  19. Distribution of fasting plasma glucose and prevalence of impaired fasting glucose, impaired glucose tolerance and type 2 diabetes in the Mexican paediatric population.

    PubMed

    Guerrero-Romero, Fernando; Violante, Rafael; Rodríguez-Morán, Martha

    2009-07-01

    Published data on the distribution of fasting plasma glucose (FPG) in children are scarce. We therefore set out to examine the distribution of FPG and determine the prevalence of impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and type 2 diabetes (T2-DM) in Mexican children aged 6-18 years in a community-based cross-sectional study. A total of 1534 apparently healthy children were randomly enrolled and underwent an oral glucose tolerance test. IFG was defined by an FPG value between >or=100 and <126 mg/dL, IGT by glucose concentration 2-h post-load between >or=140 and <200 mg/dL, and T2-DM by glucose concentration 2-h post-load >or=200 mg/dL. The FPG level at the 75(th) percentile of distribution was 98.0, 100.0 and 99.0 mg/dL for children aged 6-9, 10-14 and 15-18 years, respectively; the 95(th) percentile of FPG was greater than 100 mg/dL for all the age strata. In the population overall, the prevalences of IFG, IGT, and T2-DM were 18.3%, 5.2% and 0.6%, respectively. Among obese children and adolescents, the prevalences of IFG, IGT, IFG + IGT and T2-DM were 19.1%, 5.7%, 2.5% and 1.3%. Our study shows a high prevalence of prediabetes and is the first that reports the distribution of FPG in Mexican children and adolescents.

  20. Fasting plasma glucose and 5-year incidence of diabetes in the JPHC diabetes study - suggestion for the threshold for impaired fasting glucose among Japanese.

    PubMed

    Noda, Mitsuhiko; Kato, Masayuki; Takahashi, Yoshihiko; Matsushita, Yumi; Mizoue, Tetsuya; Inoue, Manami; Tsugane, Shoichiro; Kadowaki, Takashi

    2010-01-01

    To determine the optimal fasting plasma glucose (FPG) cut-off value which effectively identifies high risk subjects for type 2 diabetes in Japanese, we conducted a population-based prospective study on diabetes as part of the Japan Public Health Center-based Prospective Study and estimated the 5-year incidence of diabetes. The subjects of the analysis of this study were 2,207 Japanese aged 51-70 at baseline from whom a fasting blood sample was collected in both the baseline and the 5-year follow-up surveys and who completed the questionnaires at both times. Diabetes was defined as an FPG value > or = 126 mg/dL (7.0 mmol/L) and/or self-reported diabetes. A total of 125 subjects developed diabetes during the 5 years after the baseline survey, and the incidence rate for a baseline FPG value of 95-99, 100-104, 105-109, 110-114, 115- 119, and 120-125 mg/dL was 6.1, 11.5, 30.3, 52.6, 86.4, and 115.2 per 1,000 person-years, respectively. The results of receiver operating characteristic curve analysis suggested that an FPG value of 102 mg/dL (5.67 mmol/L) was optimal for predicting diabetes during the next 5-years. The cut-off value was similar in both genders and in the 51- to 60-year-old group and 61- to 70-year-old group. Use of hemoglobin A(1c) level > or = 6.1% for an additional diagnostic criterion resulted in a small increment in incidence, but the cut-off value for predicting diabetes was almost the same (101 mg/dL). The results of this study suggested that the cut-off FPG value should be lowered in terms of prediction of type 2 diabetes among Japanese populations.

  1. High-efficiency fast scintillators for 'optical' soft x-ray arrays for laboratory plasma diagnostics

    SciTech Connect

    Delgado-Aparicio, L. F.; Stutman, D.; Tritz, K.; Vero, R.; Finkenthal, M.; Suliman, G.; Kaita, R.; Majeski, R.; Stratton, B.; Roquemore, L.; Tarrio, C

    2007-08-20

    Scintillator-based 'optical' soft x-ray (OSXR) arrays have been investigated as a replacement for the conventional silicon (Si)-based diode arrays used for imaging, tomographic reconstruction, magnetohydrodynamics, transport, and turbulence studies in magnetically confined fusion plasma research. An experimental survey among several scintillator candidates was performed, measuring the relative and absolute conversion efficiencies of soft x rays to visible light. Further investigations took into account glass and fiber-optic faceplates (FOPs) as substrates, and a thin aluminum foil(150 nm) to reflect the visible light emitted by the scintillator back to the optical detector.Columnar (crystal growth) thallium-doped cesium iodide (CsI:Tl) deposited on an FOP, was found to be the best candidate for the previously mentioned plasma diagnostics.Its luminescence decay time of the order of?1-10 {mu}s is thus suitable for the 10 {mu}s time resolution required for the development of scintillator-based SXR plasma diagnostics. A prototype eight channel OSXR array using CsI:Tl was designed, built,and compared to an absolute extreme ultraviolet diode counterpart: its operation on the National Spherical Torus Experiment showed a lower level of induced noise relative to the Si-based diode arrays, especially during neutral beam injection heated plasma discharges. The OSXR concept can also be implemented in less harsh environments for basic spectroscopic laboratory plasma diagnostics.

  2. High-efficiency fast scintillators for "optical" soft x-ray arrays for laboratory plasma diagnostics.

    PubMed

    Delgado-Aparicio, L F; Stutman, D; Tritz, K; Vero, R; Finkenthal, M; Suliman, G; Kaita, R; Majeski, R; Stratton, B; Roquemore, L; Tarrio, C

    2007-08-20

    Scintillator-based "optical" soft x-ray (OSXR) arrays have been investigated as a replacement for the conventional silicon (Si)-based diode arrays used for imaging, tomographic reconstruction, magnetohydrodynamics, transport, and turbulence studies in magnetically confined fusion plasma research. An experimental survey among several scintillator candidates was performed, measuring the relative and absolute conversion efficiencies of soft x rays to visible light. Further investigations took into account glass and fiber-optic face-plates (FOPs) as substrates, and a thin aluminum foil (150 nm) to reflect the visible light emitted by the scintillator back to the optical detector. Columnar (crystal growth) thallium-doped cesium iodide (CsI:Tl) deposited on an FOP, was found to be the best candidate for the previously mentioned plasma diagnostics. Its luminescence decay time of the order of approximately 1-10 micros is thus suitable for the 10 micros time resolution required for the development of scintillator-based SXR plasma diagnostics. A prototype eight channel OSXR array using CsI:Tl was designed, built, and compared to an absolute extreme ultraviolet diode counterpart: its operation on the National Spherical Torus Experiment showed a lower level of induced noise relative to the Si-based diode arrays, especially during neutral beam injection heated plasma discharges. The OSXR concept can also be implemented in less harsh environments for basic spectroscopic laboratory plasma diagnostics.

  3. Fast ion acceleration in a foil plasma heated by a multi-picosecond high intensity laser

    NASA Astrophysics Data System (ADS)

    Iwata, Natsumi; Mima, Kunioki; Sentoku, Yasuhiko; Yogo, Akifumi; Nagatomo, Hideo; Nishimura, Hiroaki; Azechi, Hiroshi

    2017-07-01

    We study the one-dimensional expansion of a thin foil plasma irradiated by a high intensity laser with multi-picosecond (ps) pulse durations by using particle-in-cell simulation. Electrons are found to recirculate around the expanding plasma for many times, which results in stochastic heating leading to increase of the electron temperature in the multi-ps time scale beyond the ponderomotive scaling. The conventional isothermal model cannot describe such an expansion of plasmas in the long time scale. We here developed a non-isothermal plasma expansion theory that takes the time dependence of electron temperature into account for describing the multi-ps interactions in one-dimensional geometry. By assuming that the time scale of electron temperature evolution is slow compared with the plasma expansion time scale, we derived a non-self-similar solution. The time evolution of ion maximum energy obtained by the non-isothermal theory explains the details of that observed in the simulation.

  4. Plasma FGF21 concentrations, adipose fibroblast growth factor receptor-1 and β-klotho expression decrease with fasting in northern elephant seals.

    PubMed

    Suzuki, Miwa; Lee, Andrew Y; Vázquez-Medina, José Pablo; Viscarra, Jose A; Crocker, Daniel E; Ortiz, Rudy M

    2015-05-15

    Fibroblast growth factor (FGF)-21 is secreted from the liver, pancreas, and adipose in response to prolonged fasting/starvation to facilitate lipid and glucose metabolism. Northern elephant seals naturally fast for several months, maintaining a relatively elevated metabolic rate to satisfy their energetic requirements. Thus, to better understand the impact of prolonged food deprivation on FGF21-associated changes, we analyzed the expression of FGF21, FGF receptor-1 (FGFR1), β-klotho (KLB; a co-activator of FGFR) in adipose, and plasma FGF21, glucose and 3-hydroxybutyrate in fasted elephant seal pups. Expression of FGFR1 and KLB mRNA decreased 98% and 43%, respectively, with fasting duration. While the 80% decrease in mean adipose FGF21 mRNA expression with fasting did not reach statistical significance, it paralleled the 39% decrease in plasma FGF21 concentrations suggesting that FGF21 is suppressed with fasting in elephant seals. Data demonstrate an atypical response of FGF21 to prolonged fasting in a mammal suggesting that FGF21-mediated mechanisms have evolved differentially in elephant seals. Furthermore, the typical fasting-induced, FGF21-mediated actions such as the inhibition of lipolysis in adipose may not be required in elephant seals as part of a naturally adapted mechanism to support their unique metabolic demands during prolonged fasting. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Plasma FGF21 Concentrations, Adipose Fibroblast Growth Factor Receptor-1 and β-Klotho Expression Decrease with Fasting in Northern Elephant Seals

    PubMed Central

    Suzuki, Miwa; Lee, Andrew; Vázquez-Medina, Jose Pablo; Viscarra, Jose A.; Crocker, Daniel E.; Ortiz, Rudy M.

    2015-01-01

    Fibroblast growth factor (FGF)-21 is secreted from the liver, pancreas, and adipose in response to prolonged fasting/starvation to facilitate lipid and glucose metabolism. Northern elephant seals naturally fast for several months, maintaining a relatively elevated metabolic rate to satisfy their energetic requirements. Thus, to better understand the impact of prolonged food deprivation on FGF21-associated changes, we analyzed the expression of FGF21, FGF receptor-1 (FGFR1), β-klotho (KLB; a co-activator of FGFR) in adipose, and plasma FGF21, glucose and 3-hydroxybutyrate in fasted elephant seal pups. Expression of FGFR1 and KLB mRNA decreased 98% and 43%, respectively, with fasting duration. While the 80% decrease in mean adipose FGF21 mRNA expression with fasting did not reach statistical significance, it paralleled the 39% decrease in plasma FGF21 concentrations suggesting that FGF21 is suppressed with fasting in elephant seals. Data demonstrate an atypical response of FGF21 to prolonged fasting in a mammal suggesting that FGF21-mediated mechanisms have evolved differentially in elephant seals. Furthermore, the typical fasting-induced, FGF21-mediated actions such as the inhibition of lipolysis in adipose may not be required in elephant seals as part of a naturally adapted mechanism to support their unique metabolic demands during prolonged fasting. PMID:25857751

  6. BENCHMARKING FAST-TO-ALFVEN MODE CONVERSION IN A COLD MAGNETOHYDRODYNAMIC PLASMA

    SciTech Connect

    Cally, Paul S.; Hansen, Shelley C. E-mail: shelley.hansen@monash.edu

    2011-09-10

    Alfven waves may be generated via mode conversion from fast magnetoacoustic waves near their reflection level in the solar atmosphere, with implications both for coronal oscillations and for active region helioseismology. In active regions this reflection typically occurs high enough that the Alfven speed a greatly exceeds the sound speed c, well above the a = c level where the fast and slow modes interact. In order to focus on the fundamental characteristics of fast/Alfven conversion, stripped of unnecessary detail, it is therefore useful to freeze out the slow mode by adopting the gravitationally stratified cold magnetohydrodynamic model c {yields} 0. This provides a benchmark for fast-to-Alfven mode conversion in more complex atmospheres. Assuming a uniform inclined magnetic field and an exponential Alfven speed profile with density scale height h, the Alfven conversion coefficient depends on three variables only: the dimensionless transverse-to-the-stratification wavenumber {kappa} = kh, the magnetic field inclination from the stratification direction {theta}, and the polarization angle {phi} of the wavevector relative to the plane containing the stratification and magnetic field directions. We present an extensive exploration of mode conversion in this parameter space and conclude that near-total conversion to outward-propagating Alfven waves typically occurs for small {theta} and large {phi} (80{sup 0}-90{sup 0}), though it is absent entirely when {theta} is exactly zero (vertical field). For wavenumbers of helioseismic interest, the conversion region is broad enough to encompass the whole chromosphere.

  7. The Effect of LC-MS Data Preprocessing Methods on the Selection of Plasma Biomarkers in Fed vs. Fasted Rats

    PubMed Central

    Gürdeniz, Gözde; Kristensen, Mette; Skov, Thomas; Dragsted, Lars O.

    2012-01-01

    The metabolic composition of plasma is affected by time passed since the last meal and by individual variation in metabolite clearance rates. Rat plasma in fed and fasted states was analyzed with liquid chromatography quadrupole-time-of-flight mass spectrometry (LC-QTOF) for an untargeted investigation of these metabolite patterns. The dataset was used to investigate the effect of data preprocessing on biomarker selection using three different softwares, MarkerLynxTM, MZmine, XCMS along with a customized preprocessing method that performs binning of m/z channels followed by summation through retention time. Direct comparison of selected features representing the fed or fasted state showed large differences between the softwares. Many false positive markers were obtained from custom data preprocessing compared with dedicated softwares while MarkerLynxTM provided better coverage of markers. However, marker selection was more reliable with the gap filling (or peak finding) algorithms present in MZmine and XCMS. Further identification of the putative markers revealed that many of the differences between the markers selected were due to variations in features representing adducts or daughter ions of the same metabolites or of compounds from the same chemical subclasses, e.g., lyso-phosphatidylcholines (LPCs) and lyso-phosphatidylethanolamines (LPEs). We conclude that despite considerable differences in the performance of the preprocessing tools we could extract the same biological information by any of them. Carnitine, branched-chain amino acids, LPCs and LPEs were identified by all methods as markers of the fed state whereas acetylcarnitine was abundant during fasting in rats. PMID:24957369

  8. Association of television viewing with fasting and 2-h postchallenge plasma glucose levels in adults without diagnosed diabetes.

    PubMed

    Dunstan, David W; Salmon, Jo; Healy, Genevieve N; Shaw, Jonathan E; Jolley, Damien; Zimmet, Paul Z; Owen, Neville

    2007-03-01

    We examined the associations of television viewing time with fasting plasma glucose (FPG) and 2-h postchallenge plasma glucose (2-h PG) levels in Australian adults. A total of 8,357 adults aged > 35 years who were free from diagnosed diabetes and who attended a population-based cross-sectional study (Australian Diabetes, Obesity and Lifestyle Study [AusDiab]) were evaluated. Measures of FPG and 2-h PG were obtained from an oral glucose tolerance test. Self-reported television viewing time (in the previous week) was assessed using an interviewer-administered questionnaire. Homeostasis model assessment (HOMA) of insulin sensitivity (HOMA-%S) and beta-cell function (HOMA-%B) were calculated based on fasting glucose and insulin concentrations. After adjustment for confounders and physical activity time, time spent watching television in women was positively associated with 2-h PG, log fasting insulin, and log HOMA-%B and inversely associated with log HOMA-%S (P < 0.05) but not with FPG. No significant associations were observed with glycemic measures in men. The beta-coefficients across categories of average hours spent watching television per day (< 1.0, 1.0-1.9, 2.0-2.9, 3.0-3.9, and > or = 4.0) for 2-h PG in women were 0 (reference), 0.009, 0.047, 0.473, and 0.501, respectively (P for trend = 0.02). Our findings highlight the unique deleterious relationship of sedentary behavior (indicated by television viewing time) and glycemic measures independent of physical activity time and adiposity status. These relationships differed according to sex and type of glucose measurement, with the 2-h PG measure being more strongly associated with television viewing. The findings suggest an important role for reducing sedentary behavior in the prevention of type 2 diabetes and cardiovascular disease, especially in women.

  9. 46 CFR 153.296 - Emergency shutdown stations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... shutdown station must contain a single remote actuator for all quick closing shutoff valves required by... on the tankship. (f) Any remote emergency actuator, such as that for a quick closing shut-off valve... remote emergency actuators. The emergency action must occur whether one or several actuators are...

  10. 30 CFR 250.603 - Emergency shutdown system.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false Emergency shutdown system. 250.603 Section 250.603 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Workover...

  11. 30 CFR 250.503 - Emergency shutdown system.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false Emergency shutdown system. 250.503 Section 250.503 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Completion...

  12. 30 CFR 250.503 - Emergency shutdown system.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Emergency shutdown system. 250.503 Section 250.503 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Completion Operations § 250.503...

  13. 30 CFR 250.603 - Emergency shutdown system.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false Emergency shutdown system. 250.603 Section 250.603 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Workover...

  14. 30 CFR 250.603 - Emergency shutdown system.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Emergency shutdown system. 250.603 Section 250.603 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Workover Operations § 250.603 Emergency...

  15. 30 CFR 250.503 - Emergency shutdown system.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false Emergency shutdown system. 250.503 Section 250.503 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Completion...

  16. 30 CFR 250.503 - Emergency shutdown system.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false Emergency shutdown system. 250.503 Section 250.503 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Completion...

  17. Avoiding compressor surge during emergency shutdown hybridturbine systems

    SciTech Connect

    Pezzini, Paolo; Tucker, David; Traverso, Alberto

    2013-01-01

    A new emergency shutdown procedure for a direct-fired fuel cell turbine hybrid power system was evaluated using a hardware-based simulation of an integrated gasifier/fuel cell/turbine hybrid cycle (IGFC), implemented through the Hybrid Performance (Hyper) project at the National Energy Technology Laboratory, U.S. Department of Energy (NETL). The Hyper facility is designed to explore dynamic operation of hybrid systems and quantitatively characterize such transient behavior. It is possible to model, test, and evaluate the effects of different parameters on the design and operation of a gasifier/fuel cell/gas turbine hybrid system and provide a means of quantifying risk mitigation strategies. An open-loop system analysis regarding the dynamic effect of bleed air, cold air bypass, and load bank is presented in order to evaluate the combination of these three main actuators during emergency shutdown. In the previous Hybrid control system architecture, catastrophic compressor failures were observed when the fuel and load bank were cut off during emergency shutdown strategy. Improvements were achieved using a nonlinear fuel valve ramp down when the load bank was not operating. Experiments in load bank operation show compressor surge and stall after emergency shutdown activation. The difficulties in finding an optimal compressor and cathode mass flow for mitigation of surge and stall using these actuators are illustrated.

  18. 2004 Fermilab fall shutdown p-bar water issues

    SciTech Connect

    Dyer, Albert; Schneider, Frank; /Fermilab

    2004-11-01

    I was assigned to Frank Schneider, who works within the Accelerator Division Water Group. Frank would educate me with issues pertaining to water flow cooling at the P-Bar facility. Also during the shutdown period, water issues in the Pre-Vault Stub Room would be addressed.

  19. Shutdown of the Federal Government: Causes, Processes, and Effects

    DTIC Science & Technology

    2013-09-25

    call CRS at 7-5700; or • see the “Key Policy Staff” table at the end of this report. For analysis of potential effects of a shutdown on the...21 Key Policy Staff...appropriations acts (e.g., entitlements like Social Security and other mandatory spending) also may be affected by a funding gap, if program execution

  20. 30 CFR 250.503 - Emergency shutdown system.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ....503 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT OF... Well-Completion Operations § 250.503 Emergency shutdown system. When well-completion operations are conducted on a platform where there are other hydrocarbon-producing wells or other hydrocarbon flow,...

  1. Chromium yeast supplementation improves fasting plasma glucose and LDL-cholesterol in streptozotocin-induced diabetic rats.

    PubMed

    Lai, Ming-Hoang; Chen, Ya-Yen; Cheng, Hsing-Hsien

    2006-11-01

    Chromium yeast supplementation has been studied for its ability to improve carbohydrate and lipid abnormalities. There have been some earlier literature-reported studies involving chromium supplementation amongst patients suffering diabetes, but the results would appear to be somewhat varied. Forty male Wistar rats (ten weeks old, 300 g in average body mass) were divided into one of four groups, namely (i) controls; (ii) controls treated with chromium yeast; (iii) diabetic controls; and (iv) diabetic rats treated with chromium yeast. In the present investigation, the effect of a four-week oral administration of chromium yeast (600 microg of Cr/kg body mass/day, by gavage) upon the glucose and lipid metabolism in streptozotocin (STZ)-induced diabetic rats was assessed. Supplemental Cr yeast decreased the fasting blood glucose amongst the STZ-diabetic rats. No significant difference was observed in plasma fructosamine levels of rats treated with chromium yeast compared to control rats. Supplemental Cr yeast did decrease the plasma low-density lipoprotein (LDL)-cholesterol level for the STZ-diabetic rats as compared to controls. We noted no significant effect of chromium supplementation upon plasma high-density lipoprotein (HDL)-cholesterol or triglycerides compared to controls. Treatment with chromium yeast significantly increased the blood and urine chromium levels for both the diabetic and normal rats compared to respective control groups. The results of these studies suggest that Cr yeast decreased the fasting blood glucose and LDL-cholesterol levels in STZ-induced diabetic rats. This raises the possibility that Cr yeast supplementation can be considered to improve carbohydrate and lipid metabolism amongst human patients featuring type 2 diabetes mellitus.

  2. Kinetic effects in the conversion of fast waves in pre-heated, low aspect ratio tokamak plasmas

    NASA Astrophysics Data System (ADS)

    Kommoshvili, K.; Cuperman, S.; Bruma, C.

    2003-03-01

    Kinetic effects in the conversion of fast waves to Alfvèn waves and their subsequent deposition in low aspect ratio (spherical) tokamaks (LARTs) have been investigated theoretically. More specifically, we have considered the consequences of incorporation of kinetic effects in the electron parallel (to the ambient magnetic field) dynamics derived by following the drift-tearing mode analysis of Chen et al (Chen L, Rutherford P H and Tang W M 1977 Phys. Rev. Lett. 39 460), and particle-conserving Krook collision operator for the passing electrons involved (Mett R R and Mahajan S M 1992 Phys. Fluids B 4 2885). The perpendicular plasma dynamics is described by a quite general resistive two-fluid (2F) model based dielectric tensor-operator (Cuperman S, Bruma C and Komoshvili K 2002 Solution of the resistive 2F wave equations for Alfvènic modes in spherical tokamak plasmas J. Plasma Phys. accepted for publication). The full-wave electromagnetic equations, formulated in terms of the vector and scalar potentials, have been solved by the aid of an advanced finite elements numerical code (Sewell G 1993 Adv. Eng. Software 17 105). Detailed solutions of the full-wave equations are obtained and compared with those corresponding to a pure resistive 2F model, this, for the illustrative pre-heated START-type device (Sykes 1994). Our results quantitatively confirm the general theory of the conversion of fast waves with subsequent power dissipation for the conditions of spherical tokamaks thus providing the required auxilliary energy source for the succesful operation of LARTs. Moreover, these results indicate the absolute necessity of using a full model for the parallel electron dynamics, i.e. including both kinetic and collisional effects.

  3. Xanthohumol lowers body weight and fasting plasma glucose in obese male Zucker fa/fa rats.

    PubMed

    Legette, Leecole L; Luna, Arlyn Y Moreno; Reed, Ralph L; Miranda, Cristobal L; Bobe, Gerd; Proteau, Rosita R; Stevens, Jan F

    2013-07-01

    Obesity contributes to increased risk for several chronic diseases including cardiovascular disease and type 2 diabetes. Xanthohumol, a prenylated flavonoid from hops (Humulus lupulus), was tested for efficacy on biomarkers of metabolic syndrome in 4 week old Zucker fa/fa rats, a rodent model of obesity. Rats received daily oral doses of xanthohumol at 0, 1.86, 5.64, and 16.9 mg/kg BW for 6 weeks. All rats were maintained on a high fat (60% kcal) AIN-93G diet for 3 weeks to induce severe obesity followed by a normal AIN-93G (15% kcal fat) diet for the last 3 weeks of the study. Weekly food intake and body weight were recorded. Plasma cholesterol, glucose, insulin, triglyceride, and monocyte chemoattractant protein-1 (MCP-1) levels were assessed using commercial assay kits. Plasma and liver tissue levels of XN and its metabolites were determined by liquid-chromatography tandem mass spectrometry. Plasma and liver tissue levels of xanthohumol were similar between low and medium dose groups and significantly (p<0.05) elevated in the highest dose group. There was a dose-dependent effect on body weight and plasma glucose levels. The highest dose group (n=6) had significantly lower plasma glucose levels compared to the control group (n=6) in male but not female rats. There was also a significant decrease in body weight for male rats in the highest dose group (16.9 mg/kg BW) compared to rats that received no xanthohumol, which was also not seen for female rats. Plasma cholesterol, insulin, triglycerides, and MCP-1 as well as food intake were not affected by treatment. The findings suggest that xanthohumol has beneficial effects on markers of metabolic syndrome.

  4. Fasting and postprandial remnant-like particle cholesterol concentrations in obese participants are associated with plasma triglycerides, insulin resistance, and body fat distribution.

    PubMed

    van Hees, Anneke M J; Saris, Wim H M; Dallinga-Thie, Geesje M; Hul, Gabby B; Martinez, J Alfredo; Oppert, Jean-Michel; Stich, Vladimir; Astrup, Arne; Arner, Peter; Sørensen, Thorkild I A; Blaak, Ellen E

    2008-12-01

    Elevated plasma concentrations of remnant-like particle cholesterol (RLP-C) are atherogenic. However, factors that determine RLP-C are not fully understood. This study evaluates which factors affect RLP-C in the fasting and postprandial state, using multiple regression analyses in a large cohort of lean and obese participants. All participants (n = 740) underwent a test meal challenge containing 95 energy % (en%) fat (energy content 50% of predicted daily resting metabolic rate). Fasting and postprandial concentrations of circulating metabolites were measured over a 3-h period. Obese participants (n = 613) also participated in a 10-wk weight loss program (-2510 kJ/d), being randomized to either a low-fat or a high-fat diet (20-25 vs. 40-45en% fat). Postprandial RLP-C was associated with fasting RLP-C, waist:hip ratio (WHR), HOMA(IR) (homeostasis model assessment index for insulin resistance) (P < 0.001), and age, independently of BMI and gender [adjusted R(2) (adj. R(2)) = 0.70). These factors were also related to fasting RLP-C (P < 0.010), along with gender and physical activity (adj. R(2) = 0.23). The dietary intervention resulted in significantly lower fasting RLP-C concentrations, independently mediated by weight loss, improvements in HOMA(IR), and the fat content of the prescribed diet. However, after inclusion of plasma triglyceride (TG), HDL-cholesterol, and FFA concentrations in the models, HOMA(IR) and WHR no longer significantly predicted fasting RLP-C, although WHR remained a predictor of postprandial RLP-C (P = 0.002). Plasma TG was strongly associated with both fasting and postprandial RLP-C (P < 0.001). In conclusion, plasma RLP-C concentrations are mainly associated with plasma TG concentrations. Interestingly, the high-fat diet was more effective at decreasing fasting RLP-C concentrations in obese participants than the low-fat diet.

  5. Fasting plasma triglyceride concentration: A possible approach to identify increased risk of statin-induced type 2 diabetes.

    PubMed

    Sung, Ki-Chul; Reaven, Gerald

    2015-09-01

    To evaluate the hypothesis that measurement of fasting plasma triglyceride concentration identifies individuals at enhanced risk of statin-induced type 2 diabetes mellitus. A retrospective analysis of data collected from routine health examinations in non-diabetic, East Asian individuals (n = 5790) with low-density lipoprotein cholesterol concentrations of ⩾3.4 mmol/L. Subjects were stratified into those with or without a triglyceride concentration of ⩾1.7 mmol/L, and comparisons made of risk factors for type 2 diabetes mellitus. Approximately 40% of men and 20% of women with elevations of both low-density lipoprotein cholesterol and triglyceride concentrations were more insulin resistant (homeostatic model assessment of insulin resistance), associated with higher plasma concentrations of HbA1c, glucose and insulin. Apparently, healthy, non-diabetic East Asian men and women with combined elevations of low-density lipoprotein cholesterol and triglyceride concentrations are glucose intolerant and insulin resistant, and thereby at enhanced risk of type 2 diabetes mellitus. Measurement of plasma triglyceride concentration can identify within a hypercholesterolemic population a subset of individuals at enhanced risk of statin-induced type 2 diabetes mellitus. © The Author(s) 2015.

  6. Fast piezoelectric valve offering controlled gas injection in magnetically confined fusion plasmas for diagnostic and fuelling purposes

    NASA Astrophysics Data System (ADS)

    Griener, M.; Schmitz, O.; Bald, K.; Bösser, D.; Cavedon, M.; De Marné, P.; Eich, T.; Fuchert, G.; Herrmann, A.; Kappatou, A.; Lunt, T.; Rohde, V.; Schweer, B.; Sochor, M.; Stroth, U.; Terra, A.; Wolfrum, E.

    2017-03-01

    In magnetically confined fusion plasmas controlled gas injection is crucial for plasma fuelling as well as for various diagnostic applications such as active spectroscopy. We present a new, versatile system for the injection of collimated thermal gas beams into a vacuum chamber. This system consists of a gas pressure chamber, sealed by a custom made piezo valve towards a small capillary for gas injection. The setup can directly be placed inside of the vacuum chamber of fusion devices as it is small and immune against high magnetic fields. This enables gas injection close to the plasma periphery with high duty cycles and fast switch on/off times ≲ 0.5 ms. In this work, we present the design details of this new injection system and a systematic characterization of the beam properties as well as the gas flowrates which can be accomplished. The thin and relatively short capillary yields a small divergence of the injected beam with a half opening angle of 20°. The gas box is designed for pre-fill pressures of 10 mbar up to 100 bars and makes a flowrate accessible from 1018 part/s up to 1023 part/s. It hence is a versatile system for both diagnostic as well as fuelling applications. The implementation of this system in ASDEX Upgrade will be described and its application for line ratio spectroscopy on helium will be demonstrated on a selected example.

  7. Fasting modifies Aroclor 1254 impact on plasma cortisol, glucose and lactate responses to a handling disturbance in Arctic charr

    USGS Publications Warehouse

    Jorgensen, E.H.; Vijayan, M.M.; Aluru, N.; Maule, A.G.

    2002-01-01

    Integrated effects of polychlorinated biphenyl (PCB) and nutritional status on responses to handling disturbance were investigated in the Arctic charr (Salvelinus alpinus). The fish were orally contaminated with Aroclor 1254 and held either with or without food for 5 months before they were subjected to a 10-min handling disturbance. Food-deprived fish were given 0, 1, 10 or 100 mg PCB kg-1 and the fed fish 0 or 100 mg PCB kg-1. Plasma cortisol, glucose and lactate levels were measured at 0 (pre-handling), 1, 3, 6 and 23 h after the handling disturbance. Food-deprived control fish had elevated plasma cortisol levels compared with fed fish before handling. These basal cortisol levels were suppressed by PCB in food-deprived fish, and elevated by PCB in fed fish. The immediate cortisol and glucose responses to handling disturbance were suppressed by PCB in a dose-dependent way in food-deprived fish. Although these responses were also lowered by PCB in the fed fish, the effect was much less pronounced than in food-deprived fish. There were only minor effects on plasma lactate responses. Our findings suggest that the stress responses of the Arctic charr are compromised by PCB and that the long-term fasting, typical of high-latitude fish, makes these species particularly sensitive to organochlorines such as PCB. ?? 2002 Elsevier Science Inc. All rights reserved.

  8. Nonlinear dynamics of 3D beams of fast magnetosonic waves propagating in the ionospheric and magnetospheric plasma

    NASA Astrophysics Data System (ADS)

    Belashov, V. Yu.; Belashova, E. S.

    2016-11-01

    On the basis of the model of the three-dimensional (3D) generalized Kadomtsev-Petviashvili equation for magnetic field h = B / B the formation, stability, and dynamics of 3D soliton-like structures, such as the beams of fast magnetosonic (FMS) waves generated in ionospheric and magnetospheric plasma at a low-frequency branch of oscillations when β = 4 πnT/ B 2 ≪ 1 and β > 1, are studied. The study takes into account the highest dispersion correction determined by values of the plasma parameters and the angle θ = ( B, k), which plays a key role in the FMS beam propagation at those angles to the magnetic field that are close to π/2. The stability of multidimensional solutions is studied by an investigation of the Hamiltonian boundness under its deformations on the basis of solving of the corresponding variational problem. The evolution and dynamics of the 3D FMS wave beam are studied by the numerical integration of equations with the use of specially developed methods. The results can be interpreted in terms of the self-focusing phenomenon, as the formation of a stationary beam and the scattering and self-focusing of the solitary beam of FMS waves. These cases were studied with a detailed investigation of all evolutionary stages of the 3D FMS wave beams in the ionospheric and magnetospheric plasma.

  9. Fast and sensitive analysis of dermorphin and HYP6-dermorphin in equine plasma using liquid chromatography tandem mass spectrometry.

    PubMed

    Wang, Caroline C; Hartmann-Fischbach, Petra; Krueger, Tim R; Wells, Terry L; Feineman, Amy R; Compton, Joanne C

    2014-04-01

    Dermorphin and HYP(6) -dermorphin are hepta-peptides and natural opioids originally isolated from the skin of South American frogs. They are more potent than morphine but less likely to produce drug tolerance and addiction. These properties make them ideal candidates for the doping of racehorses to enhance performance during competition. Dermorphin was recently classified as a Class I drug by Racing Commissioners International (RCI), indicating that it is a banned substance in equine athletes. To enforce this ban, a fast and sensitive method was developed for dermorphin and HYP(6)-dermorphin analysis in equine plasma. Equine plasma (2 ml) was extracted on a mixed mode cation exchange solid-phase column. After extraction, dermorphin and HYP(6)-dermorphin were separated and detected using a liquid chromatography (LC) triple quadrupole linear ion trap mass spectrometry in positive multiple-reaction-monitoring (MRM) mode. Each analysis was 3.5 min. Four MRM transitions were used for identification of each compound. The extraction procedure was efficient and the limits of detection (LOD) were 2 pg/ml and 10 pg/ml for dermorphin and HYP(6)-dermorphin, respectively. The method has good selectivity and precision. Results of stability studies showed that both analytes were stable at low temperature. This is the first report of dermorphin and HYP(6)-dermorphin analysis in equine plasma, which could be adopted as a regular screening or confirmation method for controlling the abuse of these compounds in equine sports. Copyright © 2013 John Wiley & Sons, Ltd.

  10. Impact of Pre-Plasma on Fast Electron Generation and Transport from Short Pulse High Intensity Lasers

    NASA Astrophysics Data System (ADS)

    Peebles, J.; McGuffey, C.; Krauland, C.; Jarrott, L. C.; Sorokovikova, A.; Qiao, B.; Krasheninnikov, S.; Beg, F. N.; Wei, M. S.; Park, J.; Link, A.; Chen, H.; McLean, H. S.; Wagner, C.; Minello, V.; McCary, E.; Meadows, A.; Spinks, M.; Gaul, E.; Dyer, G.; Hegelich, B. M.; Martinez, M.; Donovan, M.; Ditmire, T.

    2014-10-01

    We present the results and analysis from recent short pulse laser matter experiments using the Texas Petawatt Laser to study the impact of pre-plasma on fast electron generation and transport. The experimental setup consisted of 3 separate beam elements: a main, high intensity, short pulse beam for the interaction, a secondary pulse of equal intensity interacting with a separate thin foil target to generate protons for side-on proton imaging and a third, low intensity, wider beam to generate a varied scale length pre-plasma. The main target consisted of a multilayer planar Al foil with a buried Cu fluor layer. The electron beam was characterized with multiple diagnostics, including several bremsstrahlung spectrometers, magnetic electron spectrometers and Cu-K α imaging. The protons from the secondary target were used to image the fields on the front of the target in the region of laser plasma interaction. Features seen in the interaction region by these protons will be presented along with characteristics of the generated electron beam. This work performed under the auspices of the US DOE under Contracts DE-FOA-0000583 (FES, NNSA).

  11. Fast piezoelectric valve offering controlled gas injection in magnetically confined fusion plasmas for diagnostic and fuelling purposes.

    PubMed

    Griener, M; Schmitz, O; Bald, K; Bösser, D; Cavedon, M; De Marné, P; Eich, T; Fuchert, G; Herrmann, A; Kappatou, A; Lunt, T; Rohde, V; Schweer, B; Sochor, M; Stroth, U; Terra, A; Wolfrum, E

    2017-03-01

    In magnetically confined fusion plasmas controlled gas injection is crucial for plasma fuelling as well as for various diagnostic applications such as active spectroscopy. We present a new, versatile system for the injection of collimated thermal gas beams into a vacuum chamber. This system consists of a gas pressure chamber, sealed by a custom made piezo valve towards a small capillary for gas injection. The setup can directly be placed inside of the vacuum chamber of fusion devices as it is small and immune against high magnetic fields. This enables gas injection close to the plasma periphery with high duty cycles and fast switch on/off times ≲ 0.5 ms. In this work, we present the design details of this new injection system and a systematic characterization of the beam properties as well as the gas flowrates which can be accomplished. The thin and relatively short capillary yields a small divergence of the injected beam with a half opening angle of 20°. The gas box is designed for pre-fill pressures of 10 mbar up to 100 bars and makes a flowrate accessible from 10(18) part/s up to 10(23) part/s. It hence is a versatile system for both diagnostic as well as fuelling applications. The implementation of this system in ASDEX Upgrade will be described and its application for line ratio spectroscopy on helium will be demonstrated on a selected example.

  12. Fast plasma discharge capillary design as a high power throughput soft x-ray emission source

    SciTech Connect

    Wyndham, E. S.; Favre, M.; Valdivia, M. P.; Valenzuela, J. C.; Chuaqui, H.; Bhuyan, H.

    2010-09-15

    We present the experimental details and results from a low energy but high repetition rate compact plasma capillary source for extreme ultraviolet and soft x-ray research and applications. Two lengths of capillary are mounted in two versions of a closely related design. The discharge operates in 1.6 and 3.2 mm inner diameter alumina capillaries of lengths 21 and 36 mm. The use of water both as dielectric and as coolant simplifies the compact low inductance design with nanosecond discharge periods. The stored electrical energy of the discharge is approximately 0.5 J and is provided by directly charging the capacitor plates from an inexpensive insulated-gate bipolar transistor in 1 {mu}s or less. We present characteristic argon spectra from plasma between 30 and 300 A as well as temporally resolved x-ray energy fluence in discrete bands on axis. The spectra also allow the level of ablated wall material to be gauged and associated with useful capillary lifetime according to the chosen configuration and energy storage. The connection between the electron beams associated with the transient hollow cathode mechanism, soft x-ray output, capillary geometry, and capillary lifetime is reported. The role of these e-beams and the plasma as measured on-axis is discussed. The relation of the electron temperature and the ionization stages observed is discussed in the context of some model results of ionization in a non-Maxwellian plasma.

  13. Fast plasma discharge capillary design as a high power throughput soft x-ray emission source.

    PubMed

    Wyndham, E S; Favre, M; Valdivia, M P; Valenzuela, J C; Chuaqui, H; Bhuyan, H

    2010-09-01

    We present the experimental details and results from a low energy but high repetition rate compact plasma capillary source for extreme ultraviolet and soft x-ray research and applications. Two lengths of capillary are mounted in two versions of a closely related design. The discharge operates in 1.6 and 3.2 mm inner diameter alumina capillaries of lengths 21 and 36 mm. The use of water both as dielectric and as coolant simplifies the compact low inductance design with nanosecond discharge periods. The stored electrical energy of the discharge is approximately 0.5 J and is provided by directly charging the capacitor plates from an inexpensive insulated-gate bipolar transistor in 1 μs or less. We present characteristic argon spectra from plasma between 30 and 300 Å as well as temporally resolved x-ray energy fluence in discrete bands on axis. The spectra also allow the level of ablated wall material to be gauged and associated with useful capillary lifetime according to the chosen configuration and energy storage. The connection between the electron beams associated with the transient hollow cathode mechanism, soft x-ray output, capillary geometry, and capillary lifetime is reported. The role of these e-beams and the plasma as measured on-axis is discussed. The relation of the electron temperature and the ionization stages observed is discussed in the context of some model results of ionization in a non-Maxwellian plasma.

  14. Fast ion generation in the cathode plasma jet of a multipicosecond laser-triggered vacuum discharge

    SciTech Connect

    Moorti, A.; Naik, P. A.; Gupta, P. D.

    2010-03-15

    Ion generation in the cathode plasma jet of a moderate-current ({approx}2.3 kA), low-energy ({<=}20 J) vacuum spark discharge triggered by {approx}27 ps, 10 mJ laser pulses is studied using time of flight technique. Fastest ion velocity and velocity corresponding to the peak of the time of flight signals for Al cathode were measured to be {approx}5.25x10{sup 8} cm/s (energy of {approx}143 keV/u) and {approx}8.1x10{sup 7} cm/s (energy of {approx}3.4 keV/u), respectively. Corresponding velocities in the case of ions generated from laser-produced Al plasma (energy of {approx}550 mJ, intensity of {approx}10{sup 14} W/cm{sup 2}) were found to be much smaller, viz., {approx}1.05x10{sup 8} cm/s (energy of {approx}5.75 keV/u) and {approx}2.63x10{sup 7} cm/s (energy of {approx}0.36 keV/u), respectively. Study shows efficient acceleration of ions in a current-carrying cathode plasma jet of a small-energy multipicosecond laser-triggered spark discharge as compared with that in a high-energy multipicosecond laser-produced plasma plume.

  15. Fast and interrupted expansion in cyclic void growth in dusty plasma

    NASA Astrophysics Data System (ADS)

    van de Wetering, F. M. J. H.; Brooimans, R. J. C.; Nijdam, S.; Beckers, J.; Kroesen, G. M. W.

    2015-01-01

    Low-pressure acetylene plasmas are able to spontaneously form dust particles. This will result in a dense cloud of solid particles that is levitated in the plasma. The formed particles can grow up to micrometers. We observed a spontaneous interruption in the expansion of the so-called dust void. A dust void is a macroscopic region in the plasma that is free of nanoparticles. The phenomenon is periodical and reproducible. We refer to the expansion interruption as ‘hiccup’. The expanding void is an environment in which a new cycle of dust particle formation can start. At a certain moment in time, this cycle reaches the (sudden) coagulation phase and as a result the void will temporarily shrink. To substantiate this reasoning, the electron density is determined non-intrusively using microwave cavity resonance spectroscopy. Moreover, video imaging of laser light scattering of the dust particles provides their spatial distribution. The emission intensity of a single argon transition is measured similarly. Our results support the aforementioned hypothesis for what happens during the void hiccup. The void dynamics preceding the hiccup are modeled using a simple analytical model for the two dominant forces (ion drag and electric) working on a nanoparticle in a plasma. The model results qualitatively reproduce the measurements.

  16. Fast plasma discharge capillary design as a high power throughput soft x-ray emission source

    NASA Astrophysics Data System (ADS)

    Wyndham, E. S.; Favre, M.; Valdivia, M. P.; Valenzuela, J. C.; Chuaqui, H.; Bhuyan, H.

    2010-09-01

    We present the experimental details and results from a low energy but high repetition rate compact plasma capillary source for extreme ultraviolet and soft x-ray research and applications. Two lengths of capillary are mounted in two versions of a closely related design. The discharge operates in 1.6 and 3.2 mm inner diameter alumina capillaries of lengths 21 and 36 mm. The use of water both as dielectric and as coolant simplifies the compact low inductance design with nanosecond discharge periods. The stored electrical energy of the discharge is approximately 0.5 J and is provided by directly charging the capacitor plates from an inexpensive insulated-gate bipolar transistor in 1 μs or less. We present characteristic argon spectra from plasma between 30 and 300 Å as well as temporally resolved x-ray energy fluence in discrete bands on axis. The spectra also allow the level of ablated wall material to be gauged and associated with useful capillary lifetime according to the chosen configuration and energy storage. The connection between the electron beams associated with the transient hollow cathode mechanism, soft x-ray output, capillary geometry, and capillary lifetime is reported. The role of these e-beams and the plasma as measured on-axis is discussed. The relation of the electron temperature and the ionization stages observed is discussed in the context of some model results of ionization in a non-Maxwellian plasma.

  17. Ion-induced gamma-ray detection of fast ions escaping from fusion plasmas

    SciTech Connect

    Nishiura, M. Mushiake, T.; Doi, K.; Wada, M.; Taniike, A.; Matsuki, T.; Shimazoe, K.; Yoshino, M.; Nagasaka, T.; Tanaka, T.; Kisaki, M.; Fujimoto, Y.; Fujioka, K.; Yamaoka, H.; Matsumoto, Y.

    2014-11-15

    A 12 × 12 pixel detector has been developed and used in a laboratory experiment for lost fast-ion diagnostics. With gamma rays in the MeV range originating from nuclear reactions {sup 9}Be(α, nγ){sup 12}C, {sup 9}Be(d, nγ){sup 12}C, and {sup 12}C(d, pγ){sup 13}C, a high purity germanium (HPGe) detector measured a fine-energy-resolved spectrum of gamma rays. The HPGe detector enables the survey of background-gamma rays and Doppler-shifted photo peak shapes. In the experiments, the pixel detector produces a gamma-ray image reconstructed from the energy spectrum obtained from total photon counts of irradiation passing through the detector's lead collimator. From gamma-ray image, diagnostics are able to produce an analysis of the fast ion loss onto the first wall in principle.

  18. Plasma produced by impacts of fast dust particles on a thin film

    NASA Technical Reports Server (NTRS)

    Auer, Siegfried

    1994-01-01

    The thin-film impact plasma detector was pioneered by Berg for detecting small cosmic dust particles and measuring their approximate velocities in a time-of-flight configuration. While Berg's device was highly successful in establishing the flux of interplanetary dust, the accuracy of measuring the velocities of individual particles was a moderate 18 percent in magnitude and 27 degrees in angle. A much greater accuracy of less than or equal to 1 percent in determining the velocity components appears desirable in order to associate a particle with its parent body. In order to meet that need, research was initiated to determine if a thin-film detector can be designed to provide such accurate velocity measurements. Previous laboratory investigations of the impact plasma uncovered two difficulties: (1) solid or liquid spray is ejected from a primary impact crater and strikes neighboring walls where it produces secondary impact craters and plasma clouds; as a result, both quantity and time of detection of the plasma can vary significantly with the experiment configuration. Particles from an accelerator rarely have speeds v greater than or equal to 10-15 km/s, while cosmic dust particles typically impact at v = 10-72 km/s. The purpose of the tests discussed in this paper was to resolve the two difficulties mentioned. That is, the experiment configuration was designed to reduce the contribution of plasma from secondary impacts. In addition, most particles with v less than or equal to 25 km/s and all particles with v less than or equal to 10 km/s were eliminated from the beam.

  19. Plasma produced by impacts of fast dust particles on a thin film

    NASA Astrophysics Data System (ADS)

    Auer, Siegfried

    The thin-film impact plasma detector was pioneered by Berg for detecting small cosmic dust particles and measuring their approximate velocities in a time-of-flight configuration. While Berg's device was highly successful in establishing the flux of interplanetary dust, the accuracy of measuring the velocities of individual particles was a moderate 18 percent in magnitude and 27 degrees in angle. A much greater accuracy of less than or equal to 1 percent in determining the velocity components appears desirable in order to associate a particle with its parent body. In order to meet that need, research was initiated to determine if a thin-film detector can be designed to provide such accurate velocity measurements. Previous laboratory investigations of the impact plasma uncovered two difficulties: (1) solid or liquid spray is ejected from a primary impact crater and strikes neighboring walls where it produces secondary impact craters and plasma clouds; as a result, both quantity and time of detection of the plasma can vary significantly with the experiment configuration. Particles from an accelerator rarely have speeds v greater than or equal to 10-15 km/s, while cosmic dust particles typically impact at v = 10-72 km/s. The purpose of the tests discussed in this paper was to resolve the two difficulties mentioned. That is, the experiment configuration was designed to reduce the contribution of plasma from secondary impacts. In addition, most particles with v less than or equal to 25 km/s and all particles with v less than or equal to 10 km/s were eliminated from the beam.

  20. SiC detectors for radiation sources characterization and fast plasma diagnostic

    NASA Astrophysics Data System (ADS)

    Cannavò, A.; Torrisi, L.

    2016-09-01

    Semiconductor detectors based on SiC have been investigated to characterize the radiations (photons and particles) emitted from different sources, such as radioactive sources, electron guns, X-ray tubes and laser-generated plasmas. Detectors show high response velocity, low leakage current, high energy gap and high radiation hardness. Their high detection efficiency permits to use the detectors in spectroscopic mode and in time-of-flight (TOF) approach, generally employed to monitor low and high radiation fluxes, respectively. Using the laser start signal, they permit to study the properties of the generated plasma in vacuum by measuring accurately the particle velocity and energy using pulsed lasers at low and high intensities. Possible applications will be reported and discussed.

  1. Ultra-intense, short pulse laser-plasma interactions with applications to the fast ignitor

    SciTech Connect

    Wilks, S.C.; Kruer, W.L.; Young, P.E.; Hammer, J.; Tabak, M.

    1995-04-01

    Due to the advent of chirped pulse amplification (CPA) as an efficient means of creating ultra-high intensity laser light (I > 5{times}10{sup 17} W/cm{sup 2}) in pulses less than a few picoseconds, new ideas for achieving ignition and gain in DT targets with less than 1 megajoule of input energy are currently being pursued. Two types of powerful lasers are employed in this scheme: (1) channeling beams and (2) ignition beams. The current state of laser-plasma interactions relating to this fusion scheme will be discussed. In particular, plasma physics issues in the ultra-intense regime are crucial to the success of this scheme. We compare simulation and experimental results in this highly nonlinear regime.

  2. Fast electrons generated by quasistatic electric fields of a fs-laser-pulse-induced plasma

    NASA Astrophysics Data System (ADS)

    Kleeschulte, F.; Hagmeister, B.; Hemmers, D.; Pretzler, G.

    2017-09-01

    We present a new acceleration mechanism for electrons taking place during the interaction of an ultrashort, nonrelativistic laser pulse with a plasma generated at the surface of a solid density target. In our experiments, the plasma is created by a laser pulse with femtosecond duration and an energy of about 1 mJ focused to intensities of above 1017W/cm2 . We observe that the electron energies acquired by this mechanism exceed the ponderomotive potential of the laser by an order of magnitude. This result was reproduced and quantitatively confirmed by particle-in-cell simulations, which further revealed that the observed electron acceleration is based on quasistatic electric fields caused by the space charges of ponderomotively preaccelerated electrons. This acceleration process is examined in more detail by a simplified numerical model, which allows a qualitative explanation of the final electron energies.

  3. Influence of fasting status on the effects of coconut oil on chick plasma and lipoprotein composition.

    PubMed

    García-Fuentes, E; Gil-Villarino, A; Zafra, M F; García-Peregrín, E

    2003-06-01

    For a better understanding of the hyperlipidemic function of saturated fat, we have studied the effects of diet supplementation with 10-20% coconut oil on the chick plasma and lipoprotein composition under postprandial and starvation conditions. A significant hypercholesterolemia was found in chicks fed the standard diet after 12 h of food deprivation. In these conditions, LDL-cholesterol also increased, whereas triglyceride levels were reduced in HDL, VLDL and chylomicron fractions. Coconut oil induced a significant hypercholesterolemia under both conditions, also increasing the plasma triglyceride content under postprandial conditions, but not after starvation. Coconut oil feeding increased all the chemical components of HDL, especially under postprandial conditions, but did not affect the HDL-triglycerides under food-deprivation conditions. Total cholesterol and triglyceride levels in LDL increased after coconut oil supplementation to the diet. Differences were more pronounced under postprandial conditions. Changes in VLDL and chylomicron composition were less evident.

  4. Multiplexing slanted spiral microchannels for ultra-fast blood plasma separation.

    PubMed

    Rafeie, Mehdi; Zhang, Jun; Asadnia, Mohsen; Li, Weihua; Warkiani, Majid Ebrahimi

    2016-08-07

    Blood and blood products are critical components of health care. Blood components perform distinct functions in the human body and thus the ability to efficiently fractionate blood into its individual components (i.e., plasma and cellular components) is of utmost importance for therapeutic and diagnostic purposes. Although conventional approaches like centrifugation and membrane filtration for blood processing have been successful in generating relatively pure fractions, they are largely limited by factors such as the required blood sample volume, component purity, clogging, processing time and operation efficiency. In this work, we developed a high-throughput inertial microfluidic system for cell focusing and blood plasma separation from small to large volume blood samples (1-100 mL). Initially, polystyrene beads and blood cells were used to investigate the inertial focusing performance of a single slanted spiral microchannel as a function of particle size, flow rate, and blood cell concentration. Afterwards, blood plasma separation was conducted using an optimised spiral microchannel with relatively large dimensions. It was found that the reject ratio of the slanted spiral channel is close to 100% for blood samples with haematocrit (HCT) values of 0.5% and 1% under an optimal flow rate of 1.5 mL min(-1). Finally, through a unique multiplexing approach, we built a high-throughput system consisting of 16 spiral channels connected together, which can process diluted samples with a total flow rate as high as 24 mL min(-1). The proposed multiplexed system can surmount the shortcomings of previously reported microfluidic systems for plasma separation and cell sorting in terms of throughput, yield and operation efficiency.

  5. Acoustic mode driven by fast electrons in TJ-II Electron Cyclotron Resonance plasmas

    NASA Astrophysics Data System (ADS)

    Sun, B. J.; Ochando, M. A.; López-Bruna, D.

    2016-08-01

    Intense harmonic oscillations in radiation signals (δ I/I∼ 5{%}) are commonly observed during Electron Cyclotron Resonance (ECR) heating in TJ-II stellarator plasmas at low line-averaged electron density, 0.15 < \\bar{n}e < 0.6 ×1019 \\text{m}-3 . The frequency agrees with acoustic modes. The poloidal modal structure is compatible with Geodesic Acoustic Modes (GAM) but an n \

  6. Validating predictive models for fast ion profile relaxation in burning plasmas

    SciTech Connect

    Gorelenkov, N. N.; Heidbrink, W. W.; Kramer, G. J.; Lestz, J. B.; Podesta, M.; Van Zeeland, M. A.; White, R. B.

    2016-07-22

    The redistribution and potential loss of energetic particles due to MHD modes can limit the performance of fusion plasmas by reducing the plasma heating rate. In this work, we present validation studies of the 1.5D critical gradient model (CGM) for Alfvén eigenmode (AE) induced EP transport in NSTX and DIII-D neutral beam heated plasmas. In previous comparisons with a single DIII-D L-mode case, the CGM model was found to be responsible for 75% of measured AE induced neutron deficit [1]. A fully kinetic HINST is used to compute mode stability for the non-perturbative version of CGM (or nCGM). We have found that AEs show strong local instability drive up to $\\gamma /\\omega \\sim 20\\%$ violating assumptions of perturbative approaches used in NOVA-K code. Lastly, we demonstrate that both models agree with each other and both underestimate the neutron deficit measured in DIII-D shot by approximately a factor of 2.

  7. Validating predictive models for fast ion profile relaxation in burning plasmas

    DOE PAGES

    Gorelenkov, N. N.; Heidbrink, W. W.; Kramer, G. J.; ...

    2016-07-22

    The redistribution and potential loss of energetic particles due to MHD modes can limit the performance of fusion plasmas by reducing the plasma heating rate. In this work, we present validation studies of the 1.5D critical gradient model (CGM) for Alfvén eigenmode (AE) induced EP transport in NSTX and DIII-D neutral beam heated plasmas. In previous comparisons with a single DIII-D L-mode case, the CGM model was found to be responsible for 75% of measured AE induced neutron deficit [1]. A fully kinetic HINST is used to compute mode stability for the non-perturbative version of CGM (or nCGM). We have found that AEs show strong local instability drive up tomore » $$\\gamma /\\omega \\sim 20\\%$$ violating assumptions of perturbative approaches used in NOVA-K code. Lastly, we demonstrate that both models agree with each other and both underestimate the neutron deficit measured in DIII-D shot by approximately a factor of 2.« less

  8. Fast Three Dimensional Reconstruction of Magnetohydrodynamic Equilibria in Plasma Confinement Devices

    NASA Astrophysics Data System (ADS)

    Seal, S. K.; Cianciosa, M. R.; Hirshman, S. P.; Wingen, A.; Wilcox, R. S.; Unterberg, E. A.

    2016-10-01

    High-fidelity reconstruction of plasma equilibria in confinement devices like stellarators and tokamaks with external three dimensional (3D) fields is computationally very expensive and routinely requires days, even weeks, to complete using serial approaches. Here, we present the performance results of coupling the 3D plasma reconstruction code, V3FIT, with PARVMEC, the recently developed parallel version of VMEC. We present the parallel design of this coupled software along with a scalability analysis to identify its performance bottlenecks. Dependence of its scalability limits on model parameters is derived. These analyses are supported by scaling studies on over 6,000 processor cores of a Cray XC30 supercomputer. PARVMEC, which dominates the total runtime of the reconstruction procedure, is shown to deliver speedup improvements of over one to two orders of magnitude, depending on whether the equilibrium computations are carried out in a free or fixed boundary mode. The overall speedup of the coupled reconstruction code is shown to deliver over 40X improvement enabling fusion scientists to carry out high-fidelity 3D plasma reconstruction analyses in only a few hours instead of in days/weeks for the first time. This work was supported by the U.S. D.O.E. contract DE-AC05-00OR22725.

  9. Impacts of fast meteoroids and a plasma-dust cloud over the lunar surface

    NASA Astrophysics Data System (ADS)

    Popel, S. I.; Golub', A. P.; Zelenyi, L. M.; Horányi, M.

    2017-05-01

    The possibility of the formation of a plasma-dust cloud in the exosphere of the Moon owing to impacts of meteoroids on the lunar surface is discussed. Attention is focused on dust particles at large altitudes of 10-100 km at which measurements were performed within the NASA LADEE mission. It has been shown that a melted material ejected from the lunar surface owing to the impacts of meteoroids plays an important role in the formation of the plasma-dust cloud. Drops of the melted material acquire velocities in the range between the first and second cosmic velocities for the Moon and can undergo finite motion around it. Rising over the lunar surface, liquid drops are solidified and acquire electric charges, in particular, owing to their interaction with electrons and ions of the solar wind, as well as with solar radiation. It has been shown that the number density of dust particles in the plasma-dust cloud present in the exosphere of the Moon is ≲10-8 cm-3, which is in agreement with the LADEE measurements.

  10. Validating predictive models for fast ion profile relaxation in burning plasmas

    SciTech Connect

    Gorelenkov, N. N.; Heidbrink, W. W.; Kramer, G. J.; Lestz, J. B.; Podesta, M.; Van Zeeland, M. A.; White, R. B.

    2016-07-22

    The redistribution and potential loss of energetic particles due to MHD modes can limit the performance of fusion plasmas by reducing the plasma heating rate. In this work, we present validation studies of the 1.5D critical gradient model (CGM) for Alfvén eigenmode (AE) induced EP transport in NSTX and DIII-D neutral beam heated plasmas. In previous comparisons with a single DIII-D L-mode case, the CGM model was found to be responsible for 75% of measured AE induced neutron deficit [1]. A fully kinetic HINST is used to compute mode stability for the non-perturbative version of CGM (or nCGM). We have found that AEs show strong local instability drive up to $\\gamma /\\omega \\sim 20\\%$ violating assumptions of perturbative approaches used in NOVA-K code. Lastly, we demonstrate that both models agree with each other and both underestimate the neutron deficit measured in DIII-D shot by approximately a factor of 2.

  11. Insulin resistance in obesity can be reliably identified from fasting plasma insulin.

    PubMed

    ter Horst, K W; Gilijamse, P W; Koopman, K E; de Weijer, B A; Brands, M; Kootte, R S; Romijn, J A; Ackermans, M T; Nieuwdorp, M; Soeters, M R; Serlie, M J

    2015-12-01

    Insulin resistance is the major contributor to cardiometabolic complications of obesity. We aimed to (1) establish cutoff points for insulin resistance from euglycemic hyperinsulinemic clamps (EHCs), (2) identify insulin-resistant obese subjects and (3) predict insulin resistance from routinely measured variables. We assembled data from non-obese (n=112) and obese (n=100) men who underwent two-step EHCs using [6,6-(2)H2]glucose as tracer (insulin infusion dose 20 and 60 mU m(-2) min(-1), respectively). Reference ranges for hepatic and peripheral insulin sensitivity were calculated from healthy non-obese men. Based on these reference values, obese men with preserved insulin sensitivity or insulin resistance were identified. Cutoff points for insulin-mediated suppression of endogenous glucose production (EGP) and insulin-stimulated glucose disappearance rate (Rd) were 46.5% and 37.3 μmol kg(-)(1) min(-)(1), respectively. Most obese men (78%) had EGP suppression within the reference range, whereas only 12% of obese men had Rd within the reference range. Obese men with Rd <37.3 μmol kg(-1) min(-1) did not differ from insulin-sensitive obese men in age, body mass index (BMI), body composition, fasting glucose or cholesterol, but did have higher fasting insulin (110±49 vs 63±29 pmol l(-1), P<0.001) and homeostasis model assessment of insulin resistance (HOMA-IR) (4.5±2.2 vs 2.7±1.4, P=0.004). Insulin-resistant obese men could be identified with good sensitivity (80%) and specificity (75%) from fasting insulin >74 pmol l(-1). Most obese men have hepatic insulin sensitivity within the range of non-obese controls, but below-normal peripheral insulin sensitivity, that is, insulin resistance. Fasting insulin (>74 pmol l(-1) with current insulin immunoassay) may be used for identification of insulin-resistant (or metabolically unhealthy) obese men in research and clinical settings.

  12. Generation of fast protons in moderate-intensity laser-plasma interaction from rear sheath

    NASA Astrophysics Data System (ADS)

    Tan, Zhi-Xin; Huang, Yong-Sheng; Lan, Xiao-Fei; Lu, Jian-Xin; Duan, Xiao-Jiao; Wang, Lei-Jian; Yang, Da-Wei; Guo, Shi-Lun; Wang, Nai-Yan

    2010-05-01

    Forward fast protons are generated by the moderate-intensity laser-foil interaction. Protons with maximum energy 190 keV are measured by using magnetic spectrometer and CR-39 solid state track detectors along the direction normal to the rear surface. The experimental results are also modeled by the particle-in-cell method, investigating the time-varying electron temperature and the rear sheath field. The temporal and spatial structure of the sheath electrical field, revealed in the simulation, suggests that these protons are accelerated by target normal sheath acceleration (TNSA) mechanism.

  13. A fast rise-rate, adjustable-mass-bit gas puff valve for energetic pulsed plasma experiments.

    PubMed

    Loebner, Keith T K; Underwood, Thomas C; Cappelli, Mark A

    2015-06-01

    A fast rise-rate, variable mass-bit gas puff valve based on the diamagnetic repulsion principle was designed, built, and experimentally characterized. The ability to hold the pressure rise-rate nearly constant while varying the total overall mass bit was achieved via a movable mechanical restrictor that is accessible while the valve is assembled and pressurized. The rise-rates and mass-bits were measured via piezoelectric pressure transducers for plenum pressures between 10 and 40 psig and restrictor positions of 0.02-1.33 cm from the bottom of the linear restrictor travel. The mass-bits were found to vary linearly with the restrictor position at a given plenum pressure, while rise-rates varied linearly with plenum pressure but exhibited low variation over the range of possible restrictor positions. The ability to change the operating regime of a pulsed coaxial plasma deflagration accelerator by means of altering the valve parameters is demonstrated.

  14. A fast rise-rate, adjustable-mass-bit gas puff valve for energetic pulsed plasma experiments

    SciTech Connect

    Loebner, Keith T. K. Underwood, Thomas C.; Cappelli, Mark A.

    2015-06-15

    A fast rise-rate, variable mass-bit gas puff valve based on the diamagnetic repulsion principle was designed, built, and experimentally characterized. The ability to hold the pressure rise-rate nearly constant while varying the total overall mass bit was achieved via a movable mechanical restrictor that is accessible while the valve is assembled and pressurized. The rise-rates and mass-bits were measured via piezoelectric pressure transducers for plenum pressures between 10 and 40 psig and restrictor positions of 0.02-1.33 cm from the bottom of the linear restrictor travel. The mass-bits were found to vary linearly with the restrictor position at a given plenum pressure, while rise-rates varied linearly with plenum pressure but exhibited low variation over the range of possible restrictor positions. The ability to change the operating regime of a pulsed coaxial plasma deflagration accelerator by means of altering the valve parameters is demonstrated.

  15. A fast rise-rate, adjustable-mass-bit gas puff valve for energetic pulsed plasma experiments

    NASA Astrophysics Data System (ADS)

    Loebner, Keith T. K.; Underwood, Thomas C.; Cappelli, Mark A.

    2015-06-01

    A fast rise-rate, variable mass-bit gas puff valve based on the diamagnetic repulsion principle was designed, built, and experimentally characterized. The ability to hold the pressure rise-rate nearly constant while varying the total overall mass bit was achieved via a movable mechanical restrictor that is accessible while the valve is assembled and pressurized. The rise-rates and mass-bits were measured via piezoelectric pressure transducers for plenum pressures between 10 and 40 psig and restrictor positions of 0.02-1.33 cm from the bottom of the linear restrictor travel. The mass-bits were found to vary linearly with the restrictor position at a given plenum pressure, while rise-rates varied linearly with plenum pressure but exhibited low variation over the range of possible restrictor positions. The ability to change the operating regime of a pulsed coaxial plasma deflagration accelerator by means of altering the valve parameters is demonstrated.

  16. Screening for phaeochromocytoma and paraganglioma: impact of using supine reference intervals for plasma metanephrines with samples collected from fasted/seated patients.

    PubMed

    Casey, R; Griffin, T P; Wall, D; Dennedy, M C; Bell, M; O'Shea, P M

    2017-01-01

    Background The Endocrine Society Clinical Practice Guideline on Phaeochomocytoma and Paraganglioma recommends phlebotomy for plasma-free metanephrines with patients fasted and supine using appropriately defined reference intervals. Studies have shown higher diagnostic sensitivities using these criteria. Further, with seated-sampling protocols, for result interpretation, reference intervals that do not compromise diagnostic sensitivity should be employed. Objective To determine the impact on diagnostic performance and financial cost of using supine reference intervals for result interpretation with our current plasma-free metanephrines fasted/seated-sampling protocol. Methods We conducted a retrospective cohort study of patients who underwent screening for PPGL using plasma-free metanephrines from 2009 to 2014 at Galway University Hospitals. Plasma-free metanephrines were measured using liquid chromatography-tandem mass spectrometry. Supine thresholds for plasma normetanephrine and metanephrine set at 610 pmol/L and 310 pmol/L, respectively, were used. Results A total of 183 patients were evaluated. Mean age of participants was 53.4 (±16.3) years. Five of 183 (2.7%) patients had histologically confirmed PPGL (males, n=4). Using seated reference intervals for plasma-free metanephrines, diagnostic sensitivity and specificity were 100% and 98.9%, respectively, with two false-positive cases. Application of reference intervals established in subjects supine and fasted to this cohort gave diagnostic sensitivity of 100% with specificity of 74.7%. Financial analysis of each pretesting strategy demonstrated cost-equivalence (€147.27/patient). Conclusion Our cost analysis, together with the evidence that fasted/supine-sampling for plasma-free metanephrines, offers more reliable exclusion of PPGL mandates changing our current practice. This study highlights the important advantages of standardized diagnostic protocols for plasma-free metanephrines to ensure the highest

  17. Modeling of fast neutral-beam-generated ion effects on MHD-spectroscopic observations of resistive wall mode stability in DIII-D plasmas

    SciTech Connect

    Turco, F. Hanson, J. M.; Navratil, G. A.; Turnbull, A. D.

    2015-02-15

    Experiments conducted at DIII-D investigate the role of drift kinetic damping and fast neutral beam injection (NBI)-ions in the approach to the no-wall β{sub N} limit. Modelling results show that the drift kinetic effects are significant and necessary to reproduce the measured plasma response at the ideal no-wall limit. Fast neutral-beam ions and rotation play important roles and are crucial to quantitatively match the experiment. In this paper, we report on the model validation of a series of plasmas with increasing β{sub N}, where the plasma stability is probed by active magnetohydrodynamic (MHD) spectroscopy. The response of the plasma to an externally applied field is used to probe the stable side of the resistive wall mode and obtain an indication of the proximity of the equilibrium to an instability limit. We describe the comparison between the measured plasma response and that calculated by means of the drift kinetic MARS-K code [Liu et al., Phys. Plasmas 15, 112503 (2008)], which includes the toroidal rotation, the electron and ion drift-kinetic resonances, and the presence of fast particles for the modelled plasmas. The inclusion of kinetic effects allows the code to reproduce the experimental results within ∼13% for both the amplitude and phase of the plasma response, which is a significant improvement with respect to the undamped MHD-only model. The presence of fast NBI-generated ions is necessary to obtain the low response at the highest β{sub N} levels (∼90% of the ideal no-wall limit). The toroidal rotation has an impact on the results, and a sensitivity study shows that a large variation in the predicted response is caused by the details of the rotation profiles at high β{sub N}.

  18. Addition of strawberries to the usual diet increases postprandial but not fasting non-urate plasma antioxidant activity in healthy subjects

    PubMed Central

    Prymont-Przyminska, Anna; Bialasiewicz, Piotr; Zwolinska, Anna; Sarniak, Agata; Wlodarczyk, Anna; Markowski, Jaroslaw; Rutkowski, Krzysztof P.; Nowak, Dariusz

    2016-01-01

    Strawberries can augment plasma antioxidant activity, but this may be confounded by selection of methods, time of blood sampling and concomitant dietary restrictions. We examined the effect of strawberry consumption on ferric reducing ability (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (DPPH-test) of native and non-urate plasma in healthy subjects on their usual diet. Eleven subjects consumed strawberries (500 g daily) for 9 days. Fasting and 3-h postprandial plasma and 24-h urine collection were obtained before, during and after strawberry course for FRAP, DPPH-test and polyphenols determination. Fifteen subjects served as a control in respect to plasma antioxidant activity changes and effect of 300 mg of oral ascorbate. First, 5th and 9th strawberry dose increased 3-h postprandial DPPH-test by 17.4, 17.6 and 12.6%, and FRAP by 15.5, 25.6 and 21.4% in comparison to fasting values in non-urate plasma (p<0.05). In native plasma only a trend was observed to higher postprandial values for both tests. Strawberries increased urinary urolithin A and 4-hydroxyhippuric acid whereas plasma polyphenols were stable. No changes of FRAP and DPPH-test were noted in controls and after ascorbate intake. Strawberries transiently increased non-urate plasma antioxidant activity but this cannot be attributed to direct antioxidant effect of polyphenols and ascorbate. PMID:27895386

  19. Addition of strawberries to the usual diet increases postprandial but not fasting non-urate plasma antioxidant activity in healthy subjects.

    PubMed

    Prymont-Przyminska, Anna; Bialasiewicz, Piotr; Zwolinska, Anna; Sarniak, Agata; Wlodarczyk, Anna; Markowski, Jaroslaw; Rutkowski, Krzysztof P; Nowak, Dariusz

    2016-11-01

    Strawberries can augment plasma antioxidant activity, but this may be confounded by selection of methods, time of blood sampling and concomitant dietary restrictions. We examined the effect of strawberry consumption on ferric reducing ability (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (DPPH-test) of native and non-urate plasma in healthy subjects on their usual diet. Eleven subjects consumed strawberries (500 g daily) for 9 days. Fasting and 3-h postprandial plasma and 24-h urine collection were obtained before, during and after strawberry course for FRAP, DPPH-test and polyphenols determination. Fifteen subjects served as a control in respect to plasma antioxidant activity changes and effect of 300 mg of oral ascorbate. First, 5th and 9th strawberry dose increased 3-h postprandial DPPH-test by 17.4, 17.6 and 12.6%, and FRAP by 15.5, 25.6 and 21.4% in comparison to fasting values in non-urate plasma (p<0.05). In native plasma only a trend was observed to higher postprandial values for both tests. Strawberries increased urinary urolithin A and 4-hydroxyhippuric acid whereas plasma polyphenols were stable. No changes of FRAP and DPPH-test were noted in controls and after ascorbate intake. Strawberries transiently increased non-urate plasma antioxidant activity but this cannot be attributed to direct antioxidant effect of polyphenols and ascorbate.

  20. Validating predictive models for fast ion profile relaxation in burning plasmas

    NASA Astrophysics Data System (ADS)

    Gorelenkov, N. N.; Heidbrink, W. W.; Kramer, G. J.; Lestz, J. B.; Podesta, M.; Van Zeeland, M. A.; White, R. B.

    2016-11-01

    The redistribution and potential loss of energetic particles due to MHD modes can limit the performance of fusion plasmas by reducing the plasma heating rate. In this work, we present validation studies of the 1.5D critical gradient model (CGM) for Alfvén eigenmode (AE) induced EP transport in NSTX and DIII-D neutral beam heated plasmas. In previous comparisons with a single DIII-D L-mode case, the CGM model was found to be responsible for 75% of measured AE induced neutron deficit [1]. A fully kinetic HINST is used to compute mode stability for the non-perturbative version of CGM (or nCGM). We have found that AEs show strong local instability drive up to γ /ω ∼ 20% violating assumptions of perturbative approaches used in NOVA-K code. We demonstrate that both models agree with each other and both underestimate the neutron deficit measured in DIII-D shot by approximately a factor of 2. On the other hand in NSTX the application of CGM shows good agreement for the measured flux deficit predictions. We attempt to understand these results with the help of the so-called kick model which is based on the guiding center code ORBIT. The kick model comparison gives important insight into the underlying velocity space dependence of the AE induced EP transport as well as it allows the estimate of the neutron deficit in the presence of the low frequency Alfvénic modes. Within the limitations of used models we infer that there are missing modes in the analysis which could improve the agreement with the experiments.

  1. Fast Gas Replacement in Plasma Process Chamber by Improving Gas Flow Pattern

    NASA Astrophysics Data System (ADS)

    Morishita, Sadaharu; Goto, Tetsuya; Akutsu, Isao; Ohyama, Kenji; Ito, Takashi; Ohmi, Tadahiro

    2009-01-01

    The precise and high-speed alteration of various gas species is important for realizing precise and well-controlled multiprocesses in a single plasma process chamber with high throughput. The gas replacement times in the replacement of N2 by Ar and that of H2 by Ar are measured in a microwave excited high-density and low electron-temperature plasma process chamber at various working pressures and gas flow rates, incorporating a new gas flow control system, which can avoid overshoot of the gas pressure in the chamber immediately after the valve operation, and a gradational lead screw booster pump, which can maintain excellent pumping capability for various gas species including lightweight gases such as H2 in a wide pressure region from 10-1 to 104 Pa. Furthermore, to control the gas flow pattern in the chamber, upper ceramic shower plates, which have thousands of very fine gas injection holes (numbers of 1200 and 2400) formed with optimized allocation on the plates, are adopted, while the conventional gas supply method in the microwave-excited plasma chamber uses many holes only opened at the sidewall of the chamber (gas ring). It has been confirmed that, in the replacement of N2 by Ar, a short replacement time of approximately 1 s in the cases of 133 and 13.3 Pa and approximately 3 s in the case of 4 Pa can be achieved when the upper shower plate has 2400 holes, while a replacement time longer than approximately 10 s is required for all pressure cases where the gas ring is used. In addition, thanks to the excellent pumping capability of the gradational lead screw booster pump for lightweight gases, it has also been confirmed that the replacement time of H2 by Ar is almost the same as that of N2 by Ar.

  2. Detecting Prediabetes and Diabetes: Agreement between Fasting Plasma Glucose and Oral Glucose Tolerance Test in Thai Adults.

    PubMed

    Aekplakorn, Wichai; Tantayotai, Valla; Numsangkul, Sakawduan; Sripho, Wilarwan; Tatsato, Nutchanat; Burapasiriwat, Tuanjai; Pipatsart, Rachada; Sansom, Premsuree; Luckanajantachote, Pranee; Chawarokorn, Pongpat; Thanonghan, Anek; Lakhamkaew, Watchira; Mungkung, Aungsumalin; Boonkean, Rungnapa; Chantapoon, Chanidsa; Kungsri, Mayuree; Luanseng, Kasetsak; Chaiyajit, Kornsinun

    2015-01-01

    To evaluate an agreement in identifying dysglycemia between fasting plasma glucose (FPG) and the 2 hr postprandial glucose tolerance test (OGTT) in a population with high risk of diabetes. A total of 6,884 individuals aged 35-65 years recruited for a community-based diabetes prevention program were tested for prediabetes including impaired fasting glucose (IFG) or impaired glucose tolerance (IGT), and diabetes. The agreement was assessed by Kappa statistics. Logistic regression was used to examine factors associated with missed prediabetes and diabetes by FPG. A total of 2671 (38.8%) individuals with prediabetes were identified. The prevalence of prediabetes identified by FPG and OGTT was 32.2% and 22.3%, respectively. The proportions of diabetes classified by OGTT were two times higher than those identified by FPG (11.0% versus 5.4%, resp.). The Kappa statistics for agreement of both tests was 0.55. Overall, FPG missed 46.3% of all prediabetes and 54.7% of all diabetes cases. Prediabetes was more likely to be missed by FPG among female, people aged <45 yrs, and those without family history of diabetes. The detection of prediabetes and diabetes using FPG only may miss half of the cases. Benefit of adding OGTT to FPG in some specific groups should be confirmed.

  3. 3D Ion and Electron Distribution Function Measurements from the Fast Plasma Investigation on the Magnetospheric Multiscale Mission

    NASA Astrophysics Data System (ADS)

    Giles, B. L.; Pollock, C. J.; Avanov, L. A.; Barrie, A. C.; Burch, J. L.; Chandler, M. O.; Clark, G. B.; Coffey, V. N.; Dickson, C.; Dorelli, J.; Ergun, R. E.; Fuselier, S. A.; Gershman, D. J.; Gliese, U.; Holland, M. P.; Jacques, A. D.; Kreisler, S.; Lavraud, B.; MacDonald, E.; Mauk, B.; Moore, T. E.; Mukai, T.; Nakamura, R.; Paterson, W. R.; Rager, A. C.; Saito, Y.; Salo, C.; Sauvaud, J. A.; Torbert, R. B.; Vinas, A. F.; Yokota, S.

    2015-12-01

    The primary focus of the Magnetospheric Multiscale (MMS) mission, launched in March 2015, is magnetic reconnection and associated processes. Understanding hinges critically on the kinetic physics that allows reconnection to take place. The Fast Plasma Investigation (FPI) provides electron and ion distribution functions at 4.5s cadence and, for select periods of time, at cadences of 30ms for electrons and 150ms for ions. These select time periods are chosen after in situ acquisition based on inspection of the low resolution data. Thus the FPI provides, independent of spacecraft spin rate, the time resolution needed to resolve the small, fast-moving reconnection diffusion regions. The first mission phase focuses on the dayside magnetopause and this presentation is intended to demonstrate the capabilities of FPI to resolve the important spatial scales relevant to the reconnection process. Magnetopause and other boundary crossings will be examined and the phase-space trajectories identified at the tetrahedral satellite locations through analysis of the 3D distribution functions.

  4. Detecting Prediabetes and Diabetes: Agreement between Fasting Plasma Glucose and Oral Glucose Tolerance Test in Thai Adults

    PubMed Central

    Tantayotai, Valla; Numsangkul, Sakawduan; Sripho, Wilarwan; Tatsato, Nutchanat; Burapasiriwat, Tuanjai; Pipatsart, Rachada; Sansom, Premsuree; Luckanajantachote, Pranee; Chawarokorn, Pongpat; Thanonghan, Anek; Lakhamkaew, Watchira; Mungkung, Aungsumalin; Boonkean, Rungnapa; Chantapoon, Chanidsa; Kungsri, Mayuree; Luanseng, Kasetsak; Chaiyajit, Kornsinun

    2015-01-01

    Aim. To evaluate an agreement in identifying dysglycemia between fasting plasma glucose (FPG) and the 2 hr postprandial glucose tolerance test (OGTT) in a population with high risk of diabetes. Methods. A total of 6,884 individuals aged 35–65 years recruited for a community-based diabetes prevention program were tested for prediabetes including impaired fasting glucose (IFG) or impaired glucose tolerance (IGT), and diabetes. The agreement was assessed by Kappa statistics. Logistic regression was used to examine factors associated with missed prediabetes and diabetes by FPG. Results. A total of 2671 (38.8%) individuals with prediabetes were identified. The prevalence of prediabetes identified by FPG and OGTT was 32.2% and 22.3%, respectively. The proportions of diabetes classified by OGTT were two times higher than those identified by FPG (11.0% versus 5.4%, resp.). The Kappa statistics for agreement of both tests was 0.55. Overall, FPG missed 46.3% of all prediabetes and 54.7% of all diabetes cases. Prediabetes was more likely to be missed by FPG among female, people aged <45 yrs, and those without family history of diabetes. Conclusion. The detection of prediabetes and diabetes using FPG only may miss half of the cases. Benefit of adding OGTT to FPG in some specific groups should be confirmed. PMID:26347060

  5. Fast Low-to-High Confinement Mode Bifurcation Dynamics in a Tokamak Edge Plasma Gyrokinetic Simulation.

    PubMed

    Chang, C S; Ku, S; Tynan, G R; Hager, R; Churchill, R M; Cziegler, I; Greenwald, M; Hubbard, A E; Hughes, J W

    2017-04-28

    Transport barrier formation and its relation to sheared flows in fluids and plasmas are of fundamental interest in various natural and laboratory observations and of critical importance in achieving an economical energy production in a magnetic fusion device. Here we report the first observation of an edge transport barrier formation event in an electrostatic gyrokinetic simulation carried out in a realistic diverted tokamak edge geometry under strong forcing by a high rate of heat deposition. The results show that turbulent Reynolds-stress-driven sheared E×B flows act in concert with neoclassical orbit loss to quench turbulent transport and form a transport barrier just inside the last closed magnetic flux surface.

  6. Preliminary Evaluation of Removing Used Nuclear Fuel from Shutdown Sites

    SciTech Connect

    Maheras, Steven J.; Best, Ralph E.; Ross, Steven B.; Buxton, Kenneth A.; England, Jeffery L.; McConnell, Paul E.; Massaro, Lawrence M.; Jensen, Philip J.

    2014-10-01

    This report presents a preliminary evaluation of removing used nuclear fuel (UNF) from 12 shutdown nuclear power plant sites. At these shutdown sites the nuclear power reactors have been permanently shut down and the sites have been decommissioned or are undergoing decommissioning. The shutdown sites are Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, Zion, Crystal River, Kewaunee, and San Onofre. The evaluation was divided into four components: characterization of the UNF and greater-than-Class C low-level radioactive waste (GTCC waste) inventory; a description of the on-site infrastructure and conditions relevant to transportation of UNF and GTCC waste; an evaluation of the near-site transportation infrastructure and experience relevant to shipping transportation casks containing UNF and GTCC waste, including identification of gaps in information; and, an evaluation of the actions necessary to prepare for and remove UNF and GTCC waste. The primary sources for the inventory of UNF and GTCC waste are the U.S. Department of Energy (DOE) RW-859 used nuclear fuel inventory database, industry sources such as StoreFUEL and SpentFUEL, and government sources such as the U.S. Nuclear Regulatory Commission. The primary sources for information on the conditions of site and near-site transportation infrastructure and experience included observations and information collected during visits to the Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, and Zion sites; information provided by managers at the shutdown sites; Facility Interface Data Sheets compiled for DOE in 2005; Services Planning Documents prepared for DOE in 1993 and 1994; industry publications such as Radwaste Solutions; and Google Earth. State and Regional Group representatives, a Tribal representative, and a Federal Railroad Administration representative participated in six of the shutdown site

  7. Experimental and analytical studies of passive shutdown heat removal systems

    SciTech Connect

    Pedersen, D.; Tessier, J.; Heineman, J.; Stewart, R.; Anderson, T.; August, C.; Chawla, T.; Cheung, F.B.; Despe, O.; Haupt, H.J.

    1987-01-01

    Using a naturally circulating air stream to remove shutdown decay heat from a nuclear reactor vessel is a key feature of advanced liquid metal reactor (LMR) concepts developed by potential vendors selected by the Department of Energy. General Electric and Rockwell International continue to develop innovative design concepts aimed at improving safety, lowering plant costs, simplifying plant operation, reducing construction times, and most of all, enhancing plant licensability. The reactor program at Argonne National Laboratory (ANL) provides technical support to both organizations. The method of shutdown heat removal proposed employs a totally passive cooling system that rejects heat from the reactor by radiation and natural convection to air. The system is inherently reliable since it is not subject failure modes associated with active decay cooling systems. The system is designed to assure adequate cooling of the reactor under abnormal operating conditions associated with loss of heat removal through other heat transport paths.

  8. Development of a fast EUV movie camera for study of magnetic reconnection in magnetically driven plasma jets

    NASA Astrophysics Data System (ADS)

    Chai, Kil-Byoung; Bellan, Paul

    2012-10-01

    The Caltech MHD driven jet experiment involves a low temperature (˜5 eV) and high density (˜10^21 m-3) plasma that travels at 10's of km/s. During and after formation, magnetic reconnections are observed together with kink and Rayleigh-Taylor instabilities [1]. It has also been observed that there are highly transient EUV emissions when there is magnetic reconnection. The first EUV peak occurs when flux tubes merge during formation and the second one occurs when a Rayleigh-Taylor instability causes the jet to break off from its source electrode. It would be helpful for understanding magnetic reconnection to investigate the spatial and temporal behaviors of these EUV bursts associated with magnetic reconnection. In order to achieve this, we are developing a high speed EUV movie camera. It consists of an Al coated YAG:Ce scintillator, an Au parabolic mirror (or a multilayer coated mirror for a specific EUV wavelength) and a fast framing camera (2x10^8 fps). We tested our system using visible light from the actual plasma jet and obtained image sequence with submicron time resolution.[4pt] [1] A. L. Moser and P. M. Bellan, Nature 482, 379 (2012).

  9. Factors predictive of macrosomia in pregnancies with a positive oral glucose challenge test: importance of fasting plasma glucose.

    PubMed

    Legardeur, H; Girard, G; Journy, N; Ressencourt, V; Durand-Zaleski, I; Mandelbrot, L

    2014-02-01

    The study aimed to determine the factors associated with fetal macrosomia following a positive oral glucose challenge test (OGCT). In this retrospective single-centre study of 1268 pregnancies with positive 50-g OGCTs (plasma glucose≥130mg/dL, or 7.2mmol/L), gestational diabetes mellitus (GDM) was defined as fasting plasma glucose (FPG)≥95mg/dL (5.3mmol/L) and/or postprandial glucose (PPG)≥120mg/dL (6.7mmol/L). In GDM pregnancies, the odds ratios adjusted for confounders (age, BMI, ethnicity, parity and weight gain) were 2.02 for macrosomia (Z score≥1.28) and 2.62 for severe macrosomia (Z score≥1.88). For each 10-mg/dL increase in FPG, the mean birth-weight increase was 60g. Macrosomia risk did not differ between GDM patients with normal FPG (<95mg/dL, or 5.3mmol/L) and non-diabetics, but increased significantly in cases of FPG≥95mg/dL and regardless of the level of PPG. In our study population, birth-weight and macrosomia risk were strongly correlated with FPG, suggesting that it is a simple and efficient marker for the risk of macrosomia. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  10. Fasting plasma lipids, lipoproteins and apolipoproteins in Nigerian women using combined oral and progestin-only injectable contraceptives.

    PubMed

    Oyelola, O O

    1993-05-01

    Fasting plasma lipid, lipoprotein, and apolipoprotein (apo) profiles were determined in Nigerian women using a low-dose combined oral (Lo-Feminal + Fe) (n = 18), a progestin-only injectable (Depo-Provera) (n = 16) contraceptives and matched controls (n = 18). The mean of plasma total and low-density lipoprotein (LDL) cholesterol, apo B and Lp(a) were significantly higher (p < 0.01) in women using contraceptives than the controls. The mean of total and LDL-cholesterol and apo B were also significantly higher in the oral contraceptive users than those on progestin-only injectables. Furthermore, the mean of cardiovascular disease (CVD) risk indices, total/HDL-cholesterol (p < 0.05) and LDL/HDL-cholesterol (p < 0.01), were significantly higher in women on oral contraceptives than the controls. There were no statistically significant differences between the indices in the women using progestin-only injectables and the controls. Based on this finding, it is concluded that the use of steroidal contraceptives is associated with alterations of lipid and apolipoprotein profiles in Nigerian women and that the use of low-dose combined oral contraceptives may be associated with an increased CVD risk.

  11. Extremely Nonsinusoidal Emissions and Fast Electron Phenomena from Strong Laser Pulses Obliquely P-Incident on Sharp-Edged Plasmas

    NASA Astrophysics Data System (ADS)

    Johnston, T. W.; Nikolic, L.; Tyshetskiy, Y.; Vidal, F.

    2007-11-01

    High laser harmonic light [1] emerges when the Vulcan petawatt laser's sub-ps laser pulses are obliquely incident on slab targets with extremely low pre-pulse energy. Similar work is in progress with the ALLS 200 TW Ti-Saph laser at INRS EMT. (Pulses are 24 fs at 10 Hz with 10-10 contrast, even without plasma mirrors). 2-D PIC (OSIRIS code at INRS) results on basic mechanism(s) resemble those of Gibbon [2], Naumova et al. [3] and Thaury et al. [4]. The very large and asymmetric electromagnetic ``spikes'' which account for the high harmonic content are produced by extremely concentrated 2D plasma surface currents. The connection between our 2D PIC results (also those in [3] and 1D PIC results [2,4] using the Gibbon-Bourdier moving 1D formalism[2] is also discussed, as are the fast electrons, including some related quasi-steady magnetic fields. [1] B. Dromey et al Nature Phys. Lett., 2, 456-459 (2006) [2] Paul Gibbon, Phys. Rev. Lett. 76, 50 (1996) [3] N. Naumova, et al., Phys. Rev. Lett. 93, 195003 (2004). [4] C. Thaury, et al., Nature Phys. 3, 424 (2007)

  12. Fast, deep record length, time-resolved visible spectroscopy of plasmas using fiber grids

    NASA Astrophysics Data System (ADS)

    Brockington, Samuel; Case, Andrew; Cruz, Edward; Witherspoon, F. Douglas; Horton, Robert; Klauser, Ruth; Hwang, D. Q.

    2016-10-01

    HyperV Technologies is developing a fiber-coupled, deep-record-length, low-light camera head for performing high time resolution spectroscopy on visible emission from plasma events. New solid-state Silicon Photo-Multiplier (SiPM) chips are capable of single photon event detection and high speed data acquisition. By coupling the output of a spectrometer to an imaging fiber bundle connected to a bank of amplified SiPMs, time-resolved spectroscopic imagers of 100 to 1,000 pixels can be constructed. Target pixel performance is 10 Megaframes/sec with record lengths of up to 256,000 frames yielding 25.6 milliseconds of record at10 Megasamples/sec resolution. Pixel resolutions of 8 to 12 bits are pos- sible. Pixel pitch can be refined by using grids of 100 μm to 1000 μm diameter fibers. A prototype 32-pixel spectroscopic imager employing this technique was constructed and successfully tested at the University of California at Davis Compact Toroid Injection Experiment (CTIX) as a full demonstration of the concept. Experimental results will be dis-cussed, along with future plans for the Phase 2 project, and potential applications to plasma experiments . Work supported by USDOE SBIR Grant DE-SC0013801.

  13. Fasting plasma triglycerides predict the glycaemic response to treatment of type 2 diabetes by gastric electrical stimulation. A novel lipotoxicity paradigm.

    PubMed

    Lebovitz, H E; Ludvik, B; Yaniv, I; Haddad, W; Schwartz, T; Aviv, R

    2013-06-01

    Non-stimulatory, meal-mediated electrical stimulation of the stomach (TANTALUS-DIAMOND) improves glycaemic control and causes modest weight loss in patients with Type 2 diabetes who are inadequately controlled on oral anti-diabetic medications. The magnitude of the glycaemic response in clinical studies has been variable. A preliminary analysis of data from patients who had completed 6 months of treatment indicated that the glycaemic response to the electrical stimulation was inversely related to the baseline fasting plasma triglyceride level. An analysis of 40 patients who had had detailed longitudinal studies for 12 months. Twenty-two patients with fasting plasma triglycerides ≤ 1.7 mmol/l had mean decreases in HbA1c after 3, 6 and 12 months of gastric contraction modulation treatment of -15 ± 2.1 mmol/mol (-1.39 ± 0.20%), -16 ± 2.2 mmol/mol (-1.48 ± 0.20%) and -14 ± 3.0 mmol/mol (-1.31 ± 0.26%), respectively. In contrast, 18 patients with fasting plasma triglyceride > 1.7 mmol/l had mean decreases in HbA1c of -7 ± 1.7 mmol/mol (-0.66 ± 0.16%), -5 ± 1.6 mmol/mol (-0.44 ± 0.18%) and -5 ± 1.7 mmol/mol (-0.42 ± 0.16%), respectively. Pearson's correlation coefficient between fasting plasma triglyceride and decreases in HbA1c at 12 months of treatment was 0.34 (P < 0.05). Homeostasis model assessment of insulin resistance was unchanged during 12 months of treatment in patients with high baseline fasting triglycerides, while it progressively improved in patients with low fasting plasma triglycerides. Patients with low fasting plasma triglycerides had a tendency to lose more weight than those with high fasting plasma triglycerides, but this did not achieve statistical significance. The data presented suggest the existence of a triglyceride lipotoxic mechanism that interferes with gastric/neural mediated pathways that can regulate glycaemic control in patients with type 2 diabetes. The data suggest the existence of a triglyceride lipotoxic pathway that

  14. Fasting plasma triglycerides predict the glycaemic response to treatment of Type 2 diabetes by gastric electrical stimulation. A novel lipotoxicity paradigm

    PubMed Central

    Lebovitz, H E; Ludvik, B; Yaniv, I; Haddad, W; Schwartz, T; Aviv, R

    2013-01-01

    Background Non-stimulatory, meal-mediated electrical stimulation of the stomach (TANTALUS-DIAMOND) improves glycaemic control and causes modest weight loss in patients with Type 2 diabetes who are inadequately controlled on oral anti-diabetic medications. The magnitude of the glycaemic response in clinical studies has been variable. A preliminary analysis of data from patients who had completed 6 months of treatment indicated that the glycaemic response to the electrical stimulation was inversely related to the baseline fasting plasma triglyceride level. Method An analysis of 40 patients who had had detailed longitudinal studies for 12 months. Results Twenty-two patients with fasting plasma triglycerides ≤ 1.7 mmol/l had mean decreases in HbA1c after 3, 6 and 12 months of gastric contraction modulation treatment of −15 ± 2.1 mmol/mol (−1.39 ± 0.20%), −16 ± 2.2 mmol/mol (−1.48 ± 0.20%) and −14 ± 3.0 mmol/mol (−1.31 ± 0.26%), respectively. In contrast, 18 patients with fasting plasma triglyceride > 1.7 mmol/l had mean decreases in HbA1c of −7 ± 1.7 mmol/mol (−0.66 ± 0.16%), −5 ± 1.6 mmol/mol (−0.44 ± 0.18%) and −5 ± 1.7 mmol/mol (−0.42 ± 0.16%), respectively. Pearson's correlation coefficient between fasting plasma triglyceride and decreases in HbA1c at 12 months of treatment was 0.34 (P < 0.05). Homeostasis model assessment of insulin resistance was unchanged during 12 months of treatment in patients with high baseline fasting triglycerides, while it progressively improved in patients with low fasting plasma triglycerides. Patients with low fasting plasma triglycerides had a tendency to lose more weight than those with high fasting plasma triglycerides, but this did not achieve statistical significance. Conclusions The data presented suggest the existance of a triglyceride lipotoxic mechanism that interferes with gastric/neural mediated pathways that can regulate glycaemic control in patients with type 2 diabetes. The data

  15. Precipitation of fast ion beams from the plasma sheet boundary layer

    NASA Technical Reports Server (NTRS)

    Ashour-Abdalla, M.; Zelenyi, L. M.; Bosqued, J. M.; Kovrazhkin, R. A.

    1992-01-01

    This paper presents a model of precipitated fluxes from the PSBL and CPS. Simulation results and data from Aureol-3 spacecraft indicate the presence of velocity dispersed precipitated ion structures (VDIS) at the poleward edge of the auroral oval. These structures are associated with fast ion beams in the PSBL region of the earth's magnetotail, confirming previous experimental results. The simulations also reveal possible substructuring of the VDIS. The bulk of the PSBL population which is not precipitated is very effectively thermalized and quasi-isotropized after multiple interactions with the magnetotail current layer. After each reflection cycle some part of the distribution is precipitated and forms multiple 'echoes' of VDIS. The CPS distributions occurring as a result of scattering, convection, multiple reflections and Fermi acceleration appear isotropic in the simulation model. This paper portrays the important role of the VDIS auroral region medium for complicated and energetically significant processes occurring in different regions of the distant magnetotail.

  16. The shutdown reactor: Optimizing spent fuel storage cost

    SciTech Connect

    Pennington, C.W.

    1995-12-31

    Several studies have indicated that the most prudent way to store fuel at a shutdown reactor site safely and economically is through the use of a dry storage facility licensed under 10CFR72. While such storage is certainly safe, is it true that the dry ISFSI represents the safest and most economical approach for the utility? While no one is really able to answer that question definitely, as yet, Holtec has studied this issue for some time and believes that both an economic and safety case can be made for an optimization strategy that calls for the use of both wet and dry ISFSI storage of spent fuel at some plants. For the sake of brevity, this paper summarizes some of Holtec`s findings with respect to the economics of maintaining some fuel in wet storage at a shutdown reactor. The safety issue, or more importantly the perception of safety of spent fuel in wet storage, still varies too much with the eye of the beholder, and until a more rigorous presentation of safety analyses can be made in a regulatory setting, it is not practically useful to argue about how many angels can sit on the head of a safety-related pin. Holtec is prepared to present such analyses, but this does not appear to be the proper venue. Thus, this paper simply looks at certain economic elements of a wet ISFSI at a shutdown reactor to make a prima facie case that wet storage has some attractiveness at a shutdown reactor and should not be rejected out of hand. Indeed, an optimization study at certain plants may well show the economic vitality of keeping some fuel in the pool and converting the NRC licensing coverage from 10CFR50 to 10CFR72. If the economics look attractive, then the safety issue may be confronted with a compelling interest.

  17. Fast magnetic field penetration into a plasma. Ph.D. Thesis

    SciTech Connect

    Armale, R.

    1994-01-01

    Experiments involving propagation of neutralized ion beams across a magnetic field indicate a magnetic field penetration time that is several orders of magnitude faster than the classical, Coulomb collisional or Spitzer, diffusion time. The fast penetration time is of the order of the time scale of the Hall term in Ohm`s law. In magnetohydrodynamics, the Hall current is negligible because the electrons and ions drift together in response to an electric field perpendicular to the magnetic field. For a propagating neutralized ion beam, the ion orbits are completely different from the electron orbits and the Hall current must be considered. Maxwell`s equations and the generalized Ohm`s law are combined in a fluid model to produce a nonlinear diffusion equation for the magnetic field. The equation is linearized, and analytically solved in slab, one dimensional, and cylindrical, two dimensional, geometries. In the slab case, the magnetic field evolution is governed by a diffusion equation with a complex diffusion coefficient. In the cylindrical case, the vector potential is introduced to obtain a lowest order solution of the diffusion equations which are coupled by the Hall term. In both cases, the solution contains whistler wave oscillations and classical diffusion. The whistler waves, which vanish without the Hall term, carry-in the field and determine the penetration time. There is no fast penetration unless there is a component of magnetic field normal to the beam surface which is usually absent for a good conductor. Initially, it is necessary to consider electron inertia and the consequent penetration of the normal component to a depth c/omega(sub p). In addition, it is essential to consider a component of magnetic field parallel to the beam velocity. This component may be absent initially, but is generated by the Hall effect.

  18. Intensive lifestyle intervention including high-intensity interval training program improves insulin resistance and fasting plasma glucose in obese patients.

    PubMed

    Marquis-Gravel, Guillaume; Hayami, Douglas; Juneau, Martin; Nigam, Anil; Guilbeault, Valérie; Latour, Élise; Gayda, Mathieu

    2015-01-01

    To analyze the effects of a long-term intensive lifestyle intervention including high-intensity interval training (HIIT) and Mediterranean diet (MedD) counseling on glycemic control parameters, insulin resistance and β-cell function in obese subjects. The glycemic control parameters (fasting plasma glucose, glycated hemoglobin), insulin resistance, and β-cell function of 72 obese subjects (54 women; mean age = 53 ± 9 years) were assessed at baseline and upon completion of a 9-month intensive lifestyle intervention program conducted at the cardiovascular prevention and rehabilitation center of the Montreal Heart Institute, from 2009 to 2012. The program included 2-3 weekly supervised exercise training sessions (HIIT and resistance exercise), combined to MedD counseling. Fasting plasma glucose (FPG) (mmol/L) (before: 5.5 ± 0.9; after: 5.2 ± 0.6; P < 0.0001), fasting insulin (pmol/L) (before: 98 ± 57; after: 82 ± 43; P = 0.003), and insulin resistance, as assessed by the HOMA-IR score (before: 3.6 ± 2.5; after: 2.8 ± 1.6; P = 0.0008) significantly improved, but not HbA1c (%) (before: 5.72 ± 0.55; after: 5.69 ± 0.39; P = 0.448), nor β-cell function (HOMA-β, %) (before: 149 ± 78; after: 144 ± 75; P = 0.58). Following a 9-month intensive lifestyle intervention combining HIIT and MedD counseling, obese subjects experienced significant improvements of FPG and insulin resistance. This is the first study to expose the effects of a long-term program combining HIIT and MedD on glycemic control parameters among obese subjects.

  19. Intensive lifestyle intervention including high-intensity interval training program improves insulin resistance and fasting plasma glucose in obese patients☆

    PubMed Central

    Marquis-Gravel, Guillaume; Hayami, Douglas; Juneau, Martin; Nigam, Anil; Guilbeault, Valérie; Latour, Élise; Gayda, Mathieu

    2015-01-01

    Objectives To analyze the effects of a long-term intensive lifestyle intervention including high-intensity interval training (HIIT) and Mediterranean diet (MedD) counseling on glycemic control parameters, insulin resistance and β-cell function in obese subjects. Methods The glycemic control parameters (fasting plasma glucose, glycated hemoglobin), insulin resistance, and β-cell function of 72 obese subjects (54 women; mean age = 53 ± 9 years) were assessed at baseline and upon completion of a 9-month intensive lifestyle intervention program conducted at the cardiovascular prevention and rehabilitation center of the Montreal Heart Institute, from 2009 to 2012. The program included 2–3 weekly supervised exercise training sessions (HIIT and resistance exercise), combined to MedD counseling. Results Fasting plasma glucose (FPG) (mmol/L) (before: 5.5 ± 0.9; after: 5.2 ± 0.6; P < 0.0001), fasting insulin (pmol/L) (before: 98 ± 57; after: 82 ± 43; P = 0.003), and insulin resistance, as assessed by the HOMA-IR score (before: 3.6 ± 2.5; after: 2.8 ± 1.6; P = 0.0008) significantly improved, but not HbA1c (%) (before: 5.72 ± 0.55; after: 5.69 ± 0.39; P = 0.448), nor β-cell function (HOMA-β, %) (before: 149 ± 78; after: 144 ± 75; P = 0.58). Conclusion Following a 9-month intensive lifestyle intervention combining HIIT and MedD counseling, obese subjects experienced significant improvements of FPG and insulin resistance. This is the first study to expose the effects of a long-term program combining HIIT and MedD on glycemic control parameters among obese subjects. PMID:26844086

  20. Association between fasting plasma triglycerides, all-cause and cardiovascular mortality in Czech population. Results from the HAPIEE study.

    PubMed

    Pikhart, H; Hubáček, J A; Peasey, A; Kubínová, R; Bobák, M

    2015-01-01

    Dyslipidemia is the risk factor of cardiovascular disease, but the relationship between the plasma triglyceride (TG) levels and total/cardiovascular mortality has not yet been analyzed in Slavs. The aim of our study was to analyze the association between the fasting TG levels and all-cause/cardiovascular mortality. We have examined 3,143 males and 3,650 females, aged 58.3+/-7.1 years. 729 deaths (274 cardiovascular deaths) have been registered during up to 11.8 years of follow-up. Age-sex adjusted all-cause mortality was higher in individuals with TG values 3.01-4.00 mmol/l (HR 1.37, 95 % CI 1.02-1.83, P=0.035) and over 4.00 mmol/l (HR 1.66, 95 % CI 1.21-2.27, P=0.002) when compared with a reference group (TG 1.41-1.80 mmol/l). Elevated risk remains significant when adjusted for education, marital status and unemployment. When further adjusted for smoking, BMI and dyslipidemia interventions, HR for those in above 4.00 mmol/l group decreased (1.42, P=0.04). The results have been similar when cardiovascular mortality has been examined, however, results reached statistical significance only for the TG over 4.0 mmol/l (P=0.028). Our results confirmed that enhanced plasma levels of plasma triglycerides are dose dependently associated with increased risk of all-cause mortality, however, it seems that individuals with TG values 1.8-3.0 mmol/l are not in higher risk of death.

  1. Fast, simple, and sensitive high-performance liquid chromatography method for measuring vitamins A and E in human blood plasma.

    PubMed

    Yuan, Chao; Burgyan, Maria; Bunch, Dustin R; Reineks, Edmunds; Jackson, Raymond; Steinle, Roxanne; Wang, Sihe

    2014-09-01

    Vitamins A and E are fat-soluble vitamins that play important roles in several physiological processes. Monitoring their concentrations is needed to detect deficiency and guide therapy. In this study, we developed a high-performance liquid chromatography method to measure the major forms of vitamin A (retinol) and vitamin E (α-tocopherol and γ-tocopherol) in human blood plasma. Vitamins A and E were extracted with hexane and separated on a reversed-phase column using methanol as the mobile phase. Retinol was detected by ultraviolet absorption, whereas tocopherols were detected by fluorescence emission. The chromatographic cycle time was 4.0 min per sample. The analytical measurement range was 0.03-5.14, 0.32-36.02, and 0.10-9.99 mg/L for retinol, α-tocopherol, and γ-tocopherol, respectively. Intr-aassay and total coefficient of variation were <6.0% for all compounds. This method was traceable to standard reference materials offered by the National Institute of Standards and Technology. Reference intervals were established using plasma samples collected from 51 healthy adult donors and were found to be 0.30-1.20, 6.0-23.0, and 0.3-3.2 mg/L for retinol, α-tocopherol, and γ-tocopherol, respectively. In conclusion, we developed and validated a fast, simple, and sensitive high-performance liquid chromatography method for measuring the major forms of vitamins A and E in human plasma. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Ultra-fast intensified frame images from an electron cyclotron resonance hydrogen plasma at 2.45 GHz: Some space distributions of visible and monochromatic emissions

    NASA Astrophysics Data System (ADS)

    Cortázar, O. D.; Megía-Macías, A.; Vizcaíno-de-Julián, A.; Tarvainen, O.; Komppula, J.; Koivisto, H.

    2014-02-01

    First results from an ultra-fast frame image acquisition diagnostic coupled to a 2.45 GHz microwave hydrogen discharge are presented. The plasma reactor has been modified to include a transparent doubled shielded quartz window allowing to viewing the full plasma volume. Pictures describing the breakdown process at 1 μs exposure time have been obtained for integrated visible light signal, Balmer-alpha, Balmer-beta lines, and Fulcher-band. Several different plasma emission distributions are reported. The distribution depends on the magnetic field configuration, incident microwave power, and neutral gas pressure.

  3. Ultra-fast intensified frame images from an electron cyclotron resonance hydrogen plasma at 2.45 GHz: some space distributions of visible and monochromatic emissions.

    PubMed

    Cortázar, O D; Megía-Macías, A; Vizcaíno-de-Julián, A; Tarvainen, O; Komppula, J; Koivisto, H

    2014-02-01

    First results from an ultra-fast frame image acquisition diagnostic coupled to a 2.45 GHz microwave hydrogen discharge are presented. The plasma reactor has been modified to include a transparent doubled shielded quartz window allowing to viewing the full plasma volume. Pictures describing the breakdown process at 1 μs exposure time have been obtained for integrated visible light signal, Balmer-alpha, Balmer-beta lines, and Fulcher-band. Several different plasma emission distributions are reported. The distribution depends on the magnetic field configuration, incident microwave power, and neutral gas pressure.

  4. Use of fast scopes to enable Thomson scattering measurement in presence of fluctuating plasma light.

    SciTech Connect

    McLean, H; Moller, J; Hill, D

    2004-04-19

    The addition of inexpensive high-speed oscilloscopes has enabled higher Te Thomson scattering measurements on the SSPX spheromak. Along with signal correlation techniques, the scopes allow new analyses based on the shape of the scattered laser pulse to discriminate against fluctuating background plasma light that often make gated-integrator measurements unreliable. A 1.4 J Nd:YAG laser at 1064 nm is the scattering source. Spatial locations are coupled by viewing optics and fibers to 4-wavelength-channel filter polychrometers. Ratios between the channels determine Te while summations of the channels determine density. Typically, the channel that provides scattered signal at higher Te is contaminated by fluctuating background light. Individual channels are correlated with either a modeled representation of the laser pulse or a noise-free stray light signal to extract channel amplitudes.

  5. Plasma effects on fast pair beams. III. Oblique electrostatic growth rates for perpendicular Maxwellian pair beams

    SciTech Connect

    Supsar, Markus; Schlickeiser, Reinhard E-mail: rsch@tp4.rub.de

    2014-03-10

    The distant universe is opaque to γ radiation from blazars due to gamma-gamma attenuation with extragalactic background light. This process produces electron-positron pair beams that interact with the intergalactic medium and are unstable to linear instabilities, particularly the electrostatic and Weibel instabilities. The electrostatic instability grows faster and so determines the dissipation of the free energy of the beam. Here, we generalize the calculation of the electrostatic growth rate to a beam plasma system with a Maxwellian perpendicular momentum spread and allow for oblique propagation directions. We show that the growth rate for the oblique electrostatic mode has a maximum value that is even higher than for a cold beam or for one with a constant perpendicular momentum spread.

  6. Fast Low-to-High Confinement Mode Bifurcation Dynamics in a Tokamak Edge Plasma Gyrokinetic Simulation

    NASA Astrophysics Data System (ADS)

    Chang, C. S.; Ku, S.; Tynan, G. R.; Hager, R.; Churchill, R. M.; Cziegler, I.; Greenwald, M.; Hubbard, A. E.; Hughes, J. W.

    2017-04-01

    Transport barrier formation and its relation to sheared flows in fluids and plasmas are of fundamental interest in various natural and laboratory observations and of critical importance in achieving an economical energy production in a magnetic fusion device. Here we report the first observation of an edge transport barrier formation event in an electrostatic gyrokinetic simulation carried out in a realistic diverted tokamak edge geometry under strong forcing by a high rate of heat deposition. The results show that turbulent Reynolds-stress-driven sheared E ×B flows act in concert with neoclassical orbit loss to quench turbulent transport and form a transport barrier just inside the last closed magnetic flux surface.

  7. Fast low-to-high confinement mode bifurcation dynamics in a tokamak edge plasma gyrokinetic simulation

    DOE PAGES

    Chang, C. S.; Ku, S.; Tynan, G. R.; ...

    2017-04-25

    Transport barrier formation and its relation to sheared flows in fluids and plasmas are of fundamental interest in various natural and laboratory observations and of critical importance in achieving an economical energy production in a magnetic fusion device. Here we report the first observation of an edge transport barrier formation event in an electrostatic gyrokinetic simulation carried out in a realistic diverted tokamak edge geometry under strong forcing by a high rate of heat deposition. Here, the results show that turbulent Reynolds-stress-driven sheared E x B flows act in concert with neoclassical orbit loss to quench turbulent transport and formmore » a transport barrier just inside the last closed magnetic flux surface.« less

  8. Application of laser driven fast high density plasma blocks for ion implantation

    NASA Astrophysics Data System (ADS)

    Sari, Amir H.; Osman, F.; Doolan, K. R.; Ghoranneviss, M.; Hora, H.; Höpfl, R.; Benstetter, G.; Hantehzadeh, M. H.

    2005-10-01

    The measurement of very narrow high density plasma blocks of high ion energy from targets irradiated with ps-TW laser pulses based on a new skin depth interaction process is an ideal tool for application of ion implantation in materials, especially of silicon, GaAs, or conducting polymers, for micro-electronics as well as for low cost solar cells. A further application is for ion sources in accelerators with most specifications of many orders of magnitudes advances against classical ion sources. We report on near band gap generation of defects by implantation of ions as measured by optical absorption spectra. A further connection is given for studying the particle beam transforming of n-type semiconductors into p-type and vice versa as known from sub-threshold particle beams. The advantage consists in the use of avoiding aggressive or rare chemical materials when using the beam techniques for industrial applications.

  9. FAST TRACK COMMUNICATION: A variational principle behind the van der Waals picture of strongly coupled plasmas

    NASA Astrophysics Data System (ADS)

    Frusawa, Hiroshi

    2009-02-01

    Various strong coupling theories of the one-component plasma have successfully predicted the thermodynamic and structural properties by separating the Coulomb potential into short- and long-ranged parts in ad hoc ways. Moreover, it has been demonstrated that the density-density correlation function in a mimic system with only short-ranged interactions resembles that of the full Coulomb system, revealing that the van der Waals picture applies to the strongly coupled Coulomb systems. Here we present a variational theory forming the basis of the van der Waals picture. Our approach provides hybrid formulations which combine both the liquid state theory and statistical field theory; essential use is made of the coarse-grained system with only the long-ranged part of Coulomb interactions as a reference system in introducing both the lower bound variational principle and strong coupling expansion.

  10. Mitigation of fast ions generated from laser-produced Sn plasma for extreme ultraviolet light source by H{sub 2} gas

    SciTech Connect

    Nakamura, Daisuke; Tamaru, Koji; Hashimoto, Yuki; Okada, Tatsuo; Tanaka, Hiroki; Takahashi, Akihiko

    2007-12-15

    One of the serious problems in the laser-produced plasma for an extreme ultraviolet (EUV) light source used for the next generation lithography is the generation of fast ions that damage the EUV collector optics. In this study, the mitigation of fast ions from a laser-produced Sn plasma by a H{sub 2} background gas was investigated. It has been confirmed that H{sub 2} buffer gas at a pressure of 13.3 Pa has little influence on the transmission of 13.5 nm light with an optical path length of 200 mm. The sputtering of a dummy mirror by the fast ions generated from the laser-produced Sn plasma and their mitigation were investigated by visualizing the spatial distributions of sputtered atoms using the laser-induced fluorescence (LIF) imaging method. It was evaluated that the sputtering rate by the fast ions was reduced to less than approximately 5% by H{sub 2} gas with a column density of 1.2x10{sup 21} l/m{sup 2}. The dynamics and the chemical reaction of the plasma plume containing the high energy and high density ions in a H{sub 2} background gas were also investigated by a time-resolved emission spectroscopy as well as by LIF.

  11. On The Anomalous Fast Ion Energy Diffusion in Toroidal Plasmas Due to Cavity Modes

    SciTech Connect

    N.N. Gorelenkov, N.J. Fisch and E. Fredrickson

    2010-03-09

    An enormous wave-particle diffusion coefficient along paths suitable for alpha channeling had been deduced in mode converted ion Bernstein wave experiments on Tokamak Fusion Test Reactor (TFTR) the only plausible explanation advanced for such a large diffusion coefficient was the excitation of internal cavity modes which induce particle diffusion along identical diffusion paths, but at much higher rates. Although such a mode was conjectured, it was never observed. However, recent detailed observations of high frequency compressional Alfven eigenmodes (CAEs) on the National Spherical torus Experiment (NSTX) indirectly support the existence of the related conjectured modes on TFTR. The eigenmodes responsible for the high frequency magnetic activity can be identified as CAEs through the polarization of the observed magnetic field oscillations in NSTX and through a comparison with the theoretically derived freuency dispersion relation. Here, we show how these recent observations of high frequency CAEs lend support to this explanation of the long-standing puzzle of anomalous fast ion energy diffusion on TFTR. The support of the conjecure that these internal modes could have caused the remarkable ion energy diffusion on TFTR carries significant and favorable implications for the possibilities in achieving the alpha channeling effect with small injected power in a tokamak reactor.

  12. Dynamic responses of a semi-type offshore floating wind turbine during normal state and emergency shutdown

    NASA Astrophysics Data System (ADS)

    Hu, Zhi-qiang; Li, Liang; Wang, Jin; Hu, Qiu-hao; Shen, Ma-cheng

    2016-03-01

    This paper addresses joint wind-wave induced dynamic responses of a semi-type offshore floating wind turbine (OFWT) under normal states and fault event conditions. The analysis in this paper is conducted in time domain, using an aero-hydro-servo-elastic simulation code-FAST. Owing to the unique viscous features of the reference system, the original viscous damping model implemented in FAST is replaced with a quadratic one to gain an accurate capture of viscous effects. Simulation cases involve free-decay motion in still water, steady motions in the presence of regular waves and wind as well as dynamic response in operational sea states with and without wind. Simulations also include the cases for transient responses induced by fast blade pitching after emergency shutdown. The features of platform motions, local structural loads and a typical mooring line tension force under a variety of excitations are obtained and investigated.

  13. 40 CFR 60.1220 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... during periods of startup, shutdown, and malfunction? 60.1220 Section 60.1220 Protection of Environment... Emission Limits § 60.1220 What happens to the emission limits during periods of startup, shutdown, and... waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or malfunction...

  14. 40 CFR 62.15150 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... requirements during periods of startup, shutdown, and malfunction? 62.15150 Section 62.15150 Protection of... § 62.15150 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown,...

  15. 40 CFR 60.1695 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... requirements during periods of startup, shutdown, and malfunction? 60.1695 Section 60.1695 Protection of... Requirements § 60.1695 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown,...

  16. 40 CFR 60.1220 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... during periods of startup, shutdown, and malfunction? 60.1220 Section 60.1220 Protection of Environment... Emission Limits § 60.1220 What happens to the emission limits during periods of startup, shutdown, and... waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or malfunction...

  17. 40 CFR 62.15150 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... requirements during periods of startup, shutdown, and malfunction? 62.15150 Section 62.15150 Protection of... § 62.15150 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown,...

  18. 40 CFR 60.1695 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... requirements during periods of startup, shutdown, and malfunction? 60.1695 Section 60.1695 Protection of... Requirements § 60.1695 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown,...

  19. VIDAS D-dimer: fast quantitative ELISA for measuring D-dimer in plasma.

    PubMed

    Pittet, J L; de Moerloose, P; Reber, G; Durand, C; Villard, C; Piga, N; Rolland, D; Comby, S; Dupuy, G

    1996-03-01

    VIDAS D-dimer (bioMérieux) is a new quantitative ELISA for D-dimer determination designed for the VIDAS automated system. The test contains single-dose, ready-to-use reagents and is completed within 35 min. Quantitative results are obtained from a calibration curve stored in the software of the system and expressed as fibrinogen equivalent units. The two-step capture/tag test relies on two complementary monoclonal anti-D-dimer antibodies, the second one being labeled with alkaline phosphatase. The upper limit of the measuring range is 1000 micrograms/L and the lower detection limit is <50 micrograms/L, which is below the lower limit of the reference interval (68-494 micrograms/L). Reproducibility (CV) within and between runs ranges from 5% to 7%. There is no interference from heparin, bilirubin, hemoglobin, fibrinogen degradation products, or plasma turbidity. Comparison with a conventional ELISA (y) gave good correlation (r= 0.91, n= 579) and comparable results (y= 1.35x - 148, S(y/x)= 750), especially for D-dimer concentrations ranging from 0 to 1000 micrograms/L (y= 1.09x - 10.6, r= 0.88, S(y/x)= 170).

  20. Fast data transmission in dynamic data acquisition system for plasma diagnostics

    NASA Astrophysics Data System (ADS)

    Byszuk, Adrian; Poźniak, Krzysztof; Zabołotny, Wojciech M.; Kasprowicz, Grzegorz; Wojeński, Andrzej; Cieszewski, Radosław; Juszczyk, Bartłomiej; Kolasiński, Piotr; Zienkiewicz, Paweł; Chernyshova, Maryna; Czarski, Tomasz

    2014-11-01

    This paper describes architecture of a new data acquisition system (DAQ) targeted mainly at plasma diagnostic experiments. Modular architecture, in combination with selected hardware components, allows for straightforward reconfiguration of the whole system, both offline and online. Main emphasis will be put into the implementation of data transmission subsystem in said system. One of the biggest advantages of described system is modular architecture with well defined boundaries between main components: analog frontend (AFE), digital backplane and acquisition/control software. Usage of a FPGA chips allows for a high flexibility in design of analog frontends, including ADC <--> FPGA interface. Data transmission between backplane boards and user software was accomplished with the use of industry-standard PCI Express (PCIe) technology. PCIe implementation includes both FPGA firmware and Linux device driver. High flexibility of PCIe connections was accomplished due to use of configurable PCIe switch. Whenever it's possible, described DAQ system tries to make use of standard off-the-shelf (OTF) components, including typical x86 CPU & motherboard (acting as PCIe controller) and cabling.