Sample records for h-mode st plasmas

  1. H-mode inductive coupling plasma for PVC surface treatment

    Croccolo, F.; Quintini, A.; Barni, R.; Ripamonti, M.; Malgaroli, A.; Riccardi, C.


    An inductively coupled plasma machine has been modified to be able to apply working powers in the order of 1 kW, thus switching to the real inductive H-mode. The plasma is generated by applying a 13.56 MHz radio-frequency to a λ/4 antenna outside the plasma chamber in low pressure conditions. The working gas is argon at pressure in the range from 10 to 100 Pa. With this high power source we have been able to perform plasma etching on a poly(vinyl-chloride) (PVC) film. In particular the effect of the plasma is the selective removal of hydrogen and chlorine from the sample surface. The action of the high power plasma on the sample has been proved to be much more effective than that of the low power one. Results similar to those obtained with the low power machine at about 300 W for 120 min, have been obtained with the high power source at about 600 W for 30 min. The superficial generation of a conductive layer of double C=C bonds was obtained. The samples have been investigated by means of ATR spectroscopy, FIB/SEM microscopy and micro-electrical measurements, which revealed the change in charge conductivity.

  2. H-mode development in TEXT-U limiter plasmas

    Roberts, D. R.; Bravenec, R. V.; Bengtson, R. D.; Brower, D. L.; Cima, G.; Crowley, T. P.; Darbar, A.; Edmonds, P. H.; Gasquet, H.; Gentle, K. W.; Hallock, G. A.; Heard, J. W.; Hurwitz, P. D.; Jiang, Y.; Karzhavin, Y. Y.; Lierzer, J.; Nikitin, A.; Ouroua, A.; Patterson, D. M.; Phillips, P. E.; Reedy, S.; Richards, B.; Rowan, W. L.; Schoch, P. M.; Sing, D. C.; Solano, E. R.; Storek, D.; Watts, C.; Winslow, D.; Wootton, A. J.; Zeng, L.; Zhang, B.; Zheng, S.-B.


    H-mode transitions in TEXT-U limiter plasmas have been observed at 0741-3335/38/8/004/img12 and 0741-3335/38/8/004/img13 kA (0741-3335/38/8/004/img14 kW) with at least 300 kW of central electron-cyclotron heating (ECH). These are dithering transitions which are induced by sawtooth crashes and display the typical signatures of H-modes (0741-3335/38/8/004/img15 drop, spontaneous density increase, evidence of a transport barrier). However, they show only a slight improvement over L-mode energy confinement. The vessel walls are boronized and conditioned prior to experiments to achieve low-impurity influx and particle recycling. Discharges which undergo transitions are fuelled almost entirely on residual recycling. Transitions are observed when limited on a toroidally localized top or bottom limiter and, more often, when the limiter surface is `fresh', which is achieved by alternating between top and bottom limiters on successive shots. No strong dependence upon the distance from the low-field-side limiter has been found. Transitions are not yet observed when limited on the high-field-side wall tiles or in the case of TEXT-U diverted configurations. Preliminary measurements with the 2 MeV heavy-ion beam probe (HIBP) (in the core) and Langmuir probes (in the edge) indicate that the plasma potential drops outside the q = 1 radius while only small changes are observed in the density fluctuation level.

  3. New Edge Coherent Mode Providing Continuous Transport in Long Pulse H-mode Plasmas

    Wang, H.Q.; Xu, G.S.; Wan, B.N.


    An electrostatic coherent mode near the electron diamagnetic frequency (20–90 kHz) is observed in the steep-gradient pedestal region of long pulse H-mode plasmas in the Experimental Advanced Super-conducting Tokamak, using a newly developed dual gas-puff-imaging system and diamond-coated reciproc......An electrostatic coherent mode near the electron diamagnetic frequency (20–90 kHz) is observed in the steep-gradient pedestal region of long pulse H-mode plasmas in the Experimental Advanced Super-conducting Tokamak, using a newly developed dual gas-puff-imaging system and diamond......-coated reciprocating probes. The mode propagates in the electron diamagnetic direction in the plasma frame with poloidal wavelength of ∼8 cm. The mode drives a significant outflow of particles and heat as measured directly with the probes, thus greatly facilitating long pulse H-mode sustainment. This mode shows...

  4. HHFW Heating and Current Drive Studies of NSTX H-Mode Plasmas

    G. Taylor, P.T. Bonoli, D.L. Green, R.W. Harvey, J.C. Hosea, E.F. Jaeger, B.P. LeBlanc, R. Maingi, C.K. Phillips, P.M. Ryan, E.J. Valeo, J.R. Wilson, J.C. Wright, and the NSTX Team


    30 MHz high-harmonic fast wave (HHFW) heating and current drive are being developed to assist fully non-inductive plasma current (I{sub p}) ramp-up in NSTX. The initial approach to achieving this goal has been to heat I{sub p} = 300 kA inductive plasmas with current drive antenna phasing in order to generate an HHFW H-mode with significant bootstrap and RF-driven current. Recent experiments, using only 1.4 MW of RF power (P{sub RF}), achieved a noninductive current fraction, f{sub NI} {approx} 0.65. Improved antenna conditioning resulted in the generation of I{sub p} = 650 kA HHFW H-mode plasmas, with f{sub NI} {approx} 0.35, when P{sub RF} {ge} 2.5 MW. These plasmas have little or no edge localized mode (ELM) activity during HHFW heating, a substantial increase in stored energy and a sustained central electron temperature of 5-6 keV. Another focus of NSTX HHFW research is to heat an H-mode generated by 90 keV neutral beam injection (NBI). Improved HHFW coupling to NBI-generated H-modes has resulted in a broad increase in electron temperature profile when HHFW heating is applied. Analysis of a closely matched pair of NBI and HHFW+NBI H-mode plasmas revealed that about half of the antenna power is deposited inside the last closed flux surface (LCFS). Of the power damped inside the LCFS about two-thirds is absorbed directly by electrons and one-third accelerates fast-ions that are mostly promptly lost from the plasma. At longer toroidal launch wavelengths, HHFW+NBI H-mode plasmas can have an RF power flow to the divertor outside the LCFS that significantly reduces RF power deposition to the core. ELMs can also reduce RF power deposition to the core and increase power deposition to the edge. Recent full wave modeling of NSTX HHFW+NBI H-mode plasmas, with the model extended to the vessel wall, predicts a coaxial standing mode between the LCFS and the wall that can have large amplitudes at longer launch wavelengths. These simulation results qualitatively agree with HHFW

  5. New Edge Coherent Mode Providing Continuous Transport in Long-Pulse H-mode Plasmas

    Wang, H. Q.; Xu, G. S.; Wan, B. N.; Ding, S. Y.; Guo, H. Y.; Shao, L. M.; Liu, S. C.; Xu, X. Q.; Wang, E.; Yan, N.; Naulin, V.; Nielsen, A. H.; Rasmussen, J. Juul; Candy, J.; Bravenec, R.; Sun, Y. W.; Shi, T. H.; Liang, Y. F.; Chen, R.; Zhang, W.; Wang, L.; Chen, L.; Zhao, N.; Li, Y. L.; Liu, Y. L.; Hu, G. H.; Gong, X. Z.


    An electrostatic coherent mode near the electron diamagnetic frequency (20-90 kHz) is observed in the steep-gradient pedestal region of long pulse H-mode plasmas in the Experimental Advanced Superconducting Tokamak, using a newly developed dual gas-puff-imaging system and diamond-coated reciprocating probes. The mode propagates in the electron diamagnetic direction in the plasma frame with poloidal wavelength of ˜8 cm. The mode drives a significant outflow of particles and heat as measured directly with the probes, thus greatly facilitating long pulse H-mode sustainment. This mode shows the nature of dissipative trapped electron mode, as evidenced by gyrokinetic turbulence simulations.

  6. H-mode and Edge Physics on the Pegasus ST: Progress and Future Directions

    Bongard, M. W.; Bodner, G. M.; Barr, J. L.; Burke, M. G.; Fonck, R. J.; Hinson, E. T.; Kriete, D. M.; Lewicki, B. T.; Perry, J. M.; Reusch, J. A.; Schlossberg, D. J.; Thome, K. E.; Winz, G. R.


    Ohmic H-modes are routinely attained on the Pegasus ST, in part due to the low L-H power threshold PLH arising from low-BT operation at A ~ 1 . Characteristics of H-mode include: improved τe, consistent with H98 ~ 1 edge current and pressure pedestal formation; and the occurrence of ELMs. Experiments in the past year have examined magnetic topology and density dependencies of PLH in detail. PLH exceeds ITER L-H scaling values by 10-20 ×, with PLH /PITPA 08 increasing sharply as A --> 1 . No PLH-minimizing density has been found. Unlike at high- A, PLH is insensitive to limited or diverted magnetic topologies to date. The low BT and modest pedestal values at A ~ 1 afford unique edge diagnostic accessibility to investigate ELMs and their nonlinear dynamics. Jedge (R , t) measured through a Type I ELM shows a complex pedestal collapse and filament ejection. These studies are being extended to higher Ip and longer pulse length with LHI startup to conserve Ohmic V-s and improve MHD stability. A modest-cost upgrade to the facility will enable detailed validation studies of nonlinear ELM dynamics and ELM control. This initiative will upgrade the centerstack, increasing BT by × 3 , Ohmic V-s by × 4 , and pulse lengths to 100 ms at A < 1 . 3 , as well as deploy a comprehensive 3D magnetic perturbation coil system with full poloidal coverage from frame coils and helical centerstack windings. Work supported by US DOE grant DE-FG02-96ER54375.

  7. Density limit of H-mode plasmas on JET-ILW

    Huber, A., E-mail: [Institute of Energy and Climate Research – Plasma Physics, Forschungszentrum Jülich GmbH, Trilateral Euregio Cluster, 52425 Jülich (Germany); Brezinsek, S.; Sergienko, G. [Institute of Energy and Climate Research – Plasma Physics, Forschungszentrum Jülich GmbH, Trilateral Euregio Cluster, 52425 Jülich (Germany); Groth, M. [Aalto University, Otakaari 4, 02015 Espoo (Finland); Vries, P.C. de [ITER Organisation, 13115 St Paul Lez Durance (France); Aho-Mantila, L. [VTT Technical Research Centre of Finland, 02044 VTT (Finland); Arnoux, G. [Culham Centre for Fusion Energy, Abingdon OX14 3DB (United Kingdom); Bernert, M. [Max-Planck-Institut für Plasmaphysik, D-85748 Garching (Germany); Beurskens, M.N.A. [Culham Centre for Fusion Energy, Abingdon OX14 3DB (United Kingdom); Calabro, G. [ENEA, Via Enrico Ferri 46, I-0044 Frascati (Italy); Clever, M.; Esser, H.G. [Institute of Energy and Climate Research – Plasma Physics, Forschungszentrum Jülich GmbH, Trilateral Euregio Cluster, 52425 Jülich (Germany); Guillemaut, C. [CEA, IRFM, 13108 St Paul lez Durance (France); Jachmich, S. [Laboratory for Plasma Physics, ERM/KMS, B-1000 Brussels (Belgium); Järvinen, A. [Aalto University, Otakaari 4, 02015 Espoo (Finland); Linsmeier, Ch. [Institute of Energy and Climate Research – Plasma Physics, Forschungszentrum Jülich GmbH, Trilateral Euregio Cluster, 52425 Jülich (Germany); Matthews, G.F.; Meigs, A.G. [Culham Centre for Fusion Energy, Abingdon OX14 3DB (United Kingdom); and others


    High-density discharges on JET with ITER-like Wall (ILW) have been analysed with the aim of establishing a mechanism for the H-mode density limit (DL) and compared with experiments in the JET carbon material configuration. The density limit is up to 20% higher in the JET-ILW than in the JET-C machine. The observed H-mode density limit is found close to the Greenwald limit. It is sensitive to the main plasma shape and is almost independent of the heating power. It has been observed that the transition from H-mode to L-mode is not always an abrupt event but may exhibit a series of H–L–H transitions, the so-called “dithering H-mode”. It was observed that detachment, as well as the X-point MARFE itself, does not trigger the H–L transition and thus does not present a limit on the plasma density and that it is the plasma confinement which is ultimately responsible for the H-mode DL.

  8. Progress in GYRO validation studies of DIII-D H-mode plasmas

    Holland, C.; Petty, C. C.; Schmitz, L.; Burrell, K. H.; McKee, G. R.; Rhodes, T. L.; Candy, J.


    The need for a validated predictive capability of turbulent transport in ITER is now widely recognized. However, to date most validation studies of nonlinear codes such as GYRO (Candy and Waltz 2003 J. Comput. Phys. 186 545) have focused upon low power L-mode discharges, which have significant differences in key dimensionless parameters such as ρ* = ρs/a from more ITER-relevant H-mode discharges. In order to begin addressing this gap, comparisons of the turbulent transport and fluctuations predicted by nonlinear GYRO simulations for a number of DIII-D (Luxon 2002 Nucl. Fusion 42 614) H-mode discharges to power balance analyses and experimental measurements are presented. The results of two H-mode studies are presented in this paper, this first of which investigates the importance of nonlocality at typical DIII-D H-mode ρ* values. Electrostatic global GYRO simulations of H-mode discharges at low and high rotation are shown to predict turbulence and transport levels lower than corresponding local simulations, and which are consistent with or slightly above experimental measurements and power balance analyses, even at ‘near-edge’ radii where gyrofluid and gyrokinetic models systematically underpredict turbulence and transport levels. The second study addresses the stabilizing effect of a significant density of energetic particles on turbulent transport. The results of local GYRO simulations of low-density QH-mode plasmas are presented, which model the fast beam ion population as a separate, dynamic ion species. The simulations show a significant reduction of transport with this fast ion treatment, which helps to understand previously reported results (Holland et al 2011 Phys. Plasmas 18 056113) in which GYRO simulations without this treatment significantly overpredicted (by a factor of 10 or more) power balance calculations. These results are contrasted with simulations of a high-density, low fast ion fraction QH-mode discharge, which predict transport levels

  9. Confinement and ELM characteristics of H-mode plasmas in KSTAR

    Ahn, J.-W.; Kim, H.-S.; Park, Y. S.; Terzolo, L.; Ko, W. H.; Park, J.-K.; England, A. C.; Yoon, S. W.; Jeon, Y. M.; Sabbagh, S. A.; Bae, Y. S.; Bak, J. G.; Hahn, S. H.; Hillis, D. L.; Kim, J.; Kim, W. C.; Kwak, J. G.; Lee, K. D.; Na, Y. S.; Nam, Y. U.; Oh, Y. K.; Park, S. I.


    The latest results of confinement and edge-localized mode (ELM) characteristics of Korea Superconducting Tokamak Advanced Research (KSTAR) H-mode plasmas are reported. The estimation of fast ion contribution to the total stored energy, calculated by both the NUBEAM and ASTRA simulations, and of the effective total heating power is used to derive the thermal energy confinement time (τE,thermal), which is compared with a multi-machine database. The measured power threshold for the L-H transition (Pthr) as a function of density shows a roll-over with minimum value at \\bar{n}_e \\sim 2\\times 10^{19}\\,m^{-3} . KSTAR H-mode plasmas exhibit three distinctive types of ELMs: large type-I ELMs, intermediate ELMs and a mixed (type-I and small ELM peaks) ELM regime. Power scans show that the frequency of the large ELMs increases with increasing heating power, a feature of type-I ELMs. The quality of confinement is higher for type-I and mixed ELMy H-mode (H98(y,2) ˜ 0.9-1) than for the intermediate ELM regime (H98(y,2) ˜ 0.7). Type-I ELMs have precursor-like signals from the magnetics measurement, while the other two ELM types do not. The low-field side (LFS) profile of electron temperature (Te), from the ECE measurement, and the pedestal profile of the toroidal velocity (Vt), from charge-exchange spectroscopy, show a continuous build up on the LFS during the inter-ELM period. However, the pedestal ion temperature (Ti) remains unchanged for most of the inter-ELM period until it rapidly rises in the last stage of the ELM cycle (⩾70-80%). The estimated electron pedestal collisionality for a type-I ELMy regime is v_e^\\ast \\sim 0.5{{--}}0.6 . The confinement and ELM characteristics for the ELM suppression discharges by the application of an n = 1 magnetic perturbation (MP) have also been investigated for each of the identified stages during the MP application. A second L-H transition during the L-mode phase after the end of first H-mode stage occurs for some discharges

  10. Resonant-magnetic-perturbation-induced plasma transport in H-mode pedestals

    Callen, J. D.; Hegna, C. C. [University of Wisconsin, 1500 Engineering Drive, Madison, Wisconsin 53706-1609 (United States); Cole, A. J. [Columbia University, 201 S.W. Mudd, New York, New York 10027 (United States)


    Plasma toroidal rotation reduces reconnection of externally applied resonant magnetic perturbation (RMP) fields {delta}B on rational (q = m/n) magnetic flux surfaces. Hence, it causes radial perturbations {delta}B{sub {rho}m/n} to be small there, and thus inhibits magnetic island formation and stochasticity in the edge of high (H-) mode confinement tokamak plasmas. However, electron collisional damping combined with the spatial magnetic flutter {delta}B{sub {rho}m/n} induced by RMPs in the vicinity of rational surfaces causes a radial electron heat diffusivity in which {chi}{sub e Parallel-To }{sup eff}{approx}(v{sub Te}{sup 2}/{nu}{sub e})/(1+x{sup 2}/{delta}{sub Parallel-To }{sup 2}) is an effective parallel electron thermal diffusivity. These effects are reduced by magnetic shear effects at a distance x from rational surfaces for |x|>{delta}{sub Parallel-To} but amplified for {delta}B-caret{sub {rho}m/n}(x)>{delta}B-caret{sub {rho}m/n}(0). A kinetic, toroidal model of these RMP-flutter-induced plasma transport effects is developed and compared to a previously developed cylindrical model. The RMP-induced increases in plasma transport can be large enough to reduce plasma gradients in H-mode pedestals. Thus, they may contribute to suppressing edge localized modes in tokamak plasmas.

  11. Investigation of physical processes limiting plasma density in H-mode on DIII-D

    Maingi, R.; Mahdavi, M.A. [General Atomics, San Diego, CA (United States); Jernigan, T.C. [Oak Ridge National Lab., TN (United States)] [and others


    A series of experiments was conducted on the DIII-D tokamak to investigate the physical processes which limit density in high confinement mode (H-mode) discharges. The typical H-mode to low confinement mode (L-mode) transition limit at high density near the empirical Greenwald density limit was avoided by divertor pumping, which reduced divertor neutral pressure and prevented formation of a high density, intense radiation zone (MARFE) near the X-point. It was determined that the density decay time after pellet injection was independent of density relative to the Greenwald limit and increased non-linearly with the plasma current. Magnetohydrodynamic (MHD) activity in pellet-fueled plasmas was observed at all power levels, and often caused unacceptable confinement degradation, except when the neutral beam injected (NBI) power was {le} 3 MW. Formation of MARFEs on closed field lines was avoided with low safety factor (q) operation but was observed at high q, qualitatively consistent with theory. By using pellet fueling and optimizing discharge parameters to avoid each of these limits, an operational space was accessed in which density {approximately} 1.5 {times} Greenwald limit was achieved for 600 ms, and good H-mode confinement was maintained for 300 ms of the density flattop. More significantly, the density was successfully increased to the limit where a central radiative collapse was observed, the most fundamental density limit in tokamaks.

  12. Understanding the core density profile in TCV H-mode plasmas

    Wágner, Dávid; Pitzschke, Andreas; Sauter, Olivier; Weisen, Henri


    Results from a database analysis of H-mode electron density profiles on the Tokamak \\`a Configuration Variable (TCV) in stationary conditions show that the logarithmic electron density gradient increases with collisionality. By contrast, usual observations of H-modes showed that the electron density profiles tend to flatten with increasing collisionality. In this work it is reinforced that the role of collisionality alone, depending on the parameter regime, can be rather weak and in these, dominantly electron heated TCV cases, the electron density gradient is tailored by the underlying turbulence regime, which is mostly determined by the ratio of the electron to ion temperature and that of their gradients. Additionally, mostly in ohmic plasmas, the Ware-pinch can significantly contribute to the density peaking. Qualitative agreement between the predicted density peaking by quasi-linear gyrokinetic simulations and the experimental results is found. Quantitative comparison would necessitate ion temperature meas...

  13. Magnetic-perturbation-induced plasma transport in H-mode pedestals

    Callen, J. D.; Cole, A. J.; Hegna, C. C.


    Plasma toroidal rotation can prevent reconnection of externally applied resonant magnetic perturbation (RMP) fields on rational surfaces and hence magnetic island formation and stochasticity in the edge of tokamak H-mode plasmas. However, magnetic flutter induced by RMPs off the rational surfaces causes a radial electron heat diffusivity χe^RMP˜(δBr/B0)^2χ| F(x) in which χ|˜vTe^2/νe is an effective parallel electron heat diffusivity and F is a spatially varying factor [1]. The flutter also diffuses electrons radially and causes a factor of about 3 smaller increases in density diffusion. Since the electron density transport is non-ambipolar, this flutter process also modifies the radial electric field and plasma toroidal rotation. This work extends the previously developed periodic cylinder screw pinch model [1] of RMP-flutter-induced plasma transport to a full toroidal model which is axisymmetric to lowest order plus gyroradius-small magnetic field perturbations. The possible role of the RMP-flutter-induced plasma transport in reducing pressure gradients in H-mode pedestals and thereby suppressing ELMs will be discussed.[4pt] [1] J.D. Callen et al., UW-CPTC 11-13, (submitted to Nucl. Fusion.)

  14. Predictions of Alpha Heating in ITER L-mode and H-mode Plasmas

    R.V. Budny


    Predictions of alpha heating in L-mode and H-mode DT plasmas in ITER are generated using the PTRANSP code. The baseline toroidal field of 5.3 T, plasma current ramped to 15 MA and a flat electron density profile ramped to Greenwald fraction 0.85 are assumed. Various combinations of external heating by negative ion neutral beam injection, ion cyclotron resonance, and electron cyclotron resonance are assumed to start half-way up the density ramp. The time evolution of plasma temperatures and, for some cases, toroidal rotation are predicted assuming GLF23 and boundary parameters. Significant toroidal rotation and flow-shearing rates are predicted by GLF23 even in the L-mode phase with low boundary temperatures, and the alpha heating power is predicted to be significant if the power threshold for the transition to H-mode is higher than the planned total heating power. The alpha heating is predicted to be 8-76 MW in L-mode at full density. External heating mixes with higher beam injection power have higher alpha heating power. Alternatively if the toroidal rotation is predicted assuming that the ratio of the momentum to thermal ion energy conductivity is 0.5, the flow-shearing rate is predicted to have insignificant effects on the GLF23- predicted temperatures, and alpha heating is predicted to be 8-20 MW. In H-mode plasmas the alpha heating is predicted to depend sensitively on the assumed pedestal temperatures. Cases with fusion gain greater than 10 are predicted to have alpha heating greater than 80 MW.

  15. Observation of internal transport barrier in ELMy H-mode plasmas on the EAST tokamak

    Yang, Y.; Gao, X.; Liu, H. Q.; Li, G. Q.; Zhang, T.; Zeng, L.; Liu, Y. K.; Wu, M. Q.; Kong, D. F.; Ming, T. F.; Han, X.; Wang, Y. M.; Zang, Q.; Lyu, B.; Li, Y. Y.; Duan, Y. M.; Zhong, F. B.; Li, K.; Xu, L. Q.; Gong, X. Z.; Sun, Y. W.; Qian, J. P.; Ding, B. J.; Liu, Z. X.; Liu, F. K.; Hu, C. D.; Xiang, N.; Liang, Y. F.; Zhang, X. D.; Wan, B. N.; Li, J. G.; Wan, Y. X.; EAST Team


    The internal transport barrier (ITB) has been obtained in ELMy H-mode plasmas by neutron beam injection and lower hybrid wave heating on the Experimental Advanced Superconducting Tokamak (EAST). The ITB structure has been observed in profiles of ion temperature, electron temperature, and electron density within ρ beta, β N, increases from 1.5 to near 2. The fishbone activity observed during the ITB phase suggests the central safety factor q(0) ˜ 1. Transport coefficients are calculated by particle balance and power balance analysis, showing an obvious reduction after the ITB formation.

  16. E→H mode transition density and power in two types of inductively coupled plasma configuration

    Wang, Jian; Du, Yin-chang; Zhang, Xiao; Zheng, Zhe; Liu, Yu; Xu, Liang; Wang, Pi; Cao, Jin-xiang, E-mail: [Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)


    E → H transition power and density were investigated at various argon pressures in inductively coupled plasma (ICP) in a cylindrical interlaid chamber. The transition power versus the pressure shows a minimum transition power at 4 Pa (ν/ω=1) for argon. Then the transition density hardly changes at low pressures (ν/ω≪1), but it increases clearly when argon pressure exceeds an appropriate value. In addition, both the transition power and transition density are lower in the re-entrant configuration of ICP compared with that in the cylindrical configuration of ICP. The result may be caused from the decrease of stochastic heating in the re-entrant configuration of ICP. This work is useful to understand E → H mode transition and control the transition points in real plasma processes.

  17. H-mode plasmas at very low aspect ratio on the Pegasus Toroidal Experiment

    Thome, K. E.; Bongard, M. W.; Barr, J. L.; Bodner, G. M.; Burke, M. G.; Fonck, R. J.; Kriete, D. M.; Perry, J. M.; Reusch, J. A.; Schlossberg, D. J.


    H-mode is obtained at A˜ 1.2 in the Pegasus Toroidal Experiment via Ohmic heating, high-field-side fueling, and low edge recycling in both limited and diverted magnetic topologies. These H-mode plasmas show the formation of edge current and pressure pedestals and a doubling of the energy confinement time to {{H}98y,2}˜ 1 . The L-H power threshold {{P}\\text{LH}} increases with density, and there is no {{P}\\text{LH}} minimum observed in the attainable density space. The power threshold is equivalent in limited and diverted plasmas, consistent with the FM3 model. However, the measured {{P}\\text{LH}} is ˜ 15 × higher than that predicted by conventional International Tokamak Physics Activity (ITPA) scalings, and {{P}\\text{LH}}/{{P}\\text{ITPA08}} increases as A\\to 1 . Small ELMs are present at low input power {{P}\\text{IN}}˜ {{P}\\text{LH}} , with toroidal mode number n≤slant 4 . At {{P}\\text{IN}}\\gg {{P}\\text{LH}} , they transition to large ELMs with intermediate 5. The dominant-n component of a large ELM grows exponentially, while other components evolve nonlinearly and can damp prior to the crash. Direct measurements of the current profile in the pedestal region show that both ELM types exhibit a generation of a current-hole, followed by a pedestal recovery. Large ELMs are shown to further expel a current-carrying filament. Small ELM suppression via injection of low levels of helical current into the edge plasma region is also indicated.

  18. Transport and micro-instability analysis of JET H-mode plasma during pellet fueling

    Klaywittaphat, P.; Onjun, T.


    Transport and micro-instability analysis in a JET H-mode plasma discharge 53212 during the pellet fueling operation is carried out using the BALDUR integrated predictive modeling code with a combination of the NCLASS neoclassical transport model and an anomalous core transport model (either Mixed B/gB or MMM95 model). In this work, the evolution of plasma current, plasma density and temperature profiles is carried out and, consequently, the plasma’s behaviors during the pellet operation can be observed. The NGS pellet model with the Grad-B drift effect included is used to describe pellet ablation and its behaviors when a pellet is launched into hot plasma. The simulation shows that after each pellet enters the plasma, there is a strong perturbation on the plasma causing a sudden change of both thermal and particle profiles, as well as the thermal and particle transports. For the simulation using MMM95 transport model, the change of both thermal and particle transports during pellet injection are found to be dominated by the transport due to the resistive ballooning modes due to the increase of collisionality and resistivity near the plasma edge. For the simulation based on mixed B/gB transport model, it is found that the change of transport during the pellet injection is dominated by the Bohm term. Micro-instability analysis of the plasma during the time of pellet operation is also carried out for the simulations based on MMM95 transport model. It is found that the ion temperature gradient mode is destabilized due to an increase of temperature gradient in the pellet effective region, while the trapped electron mode is stabilized due to an increase of collisionality in that region.

  19. Self-sustained turbulence and H-mode confinement in toroidal plasmas

    Itoh, Sanae-I.; Yagi, Masatoshi [Kyushu Univ., Fukuoka (Japan). Research Inst. for Applied Mechanics; Itoh, Kimitaka [National Inst. for Fusion Science, Nagoya (Japan); Fukuyama, Atsushi [Okayama Univ. (Japan). School of Engineering


    The method of self-sustained turbulence is applied to the tokamak plasma, incorporating the effect of an inhomogeneous radial electric field. The transport coefficient is derived, making a bridge between L- and H-phase plasmas. It is possible to construct a unified transport model of the L- and H-mode phases. The anomalous transport coefficients are obtained in a unified and explicit form in terms of profile parameters such as the plasma pressure gradient, the magnetic shear, the shear and curvature of the radial electric field. Strong reductions of the thermal conductivity, {chi}, the electron and ion viscosities, {mu}{sub e}, and {mu}, and the turbulent level in the H-phase plasma are explained. Furthermore, an additional stability window due to E`{sub r} is discovered in the higher pressure-gradient regime. The anomalous ion viscosity determines {Delta}, the typical scale length or E{sub r}. Self-consistent solutions of {Delta} and {mu} are discussed. (author).

  20. Modification of argon impurity transport by electron cyclotron heating in KSTAR H-mode plasmas

    Hong, Joohwan; Henderson, S. S.; Kim, Kimin; Seon, C. R.; Song, Inwoo; Lee, H. Y.; Jang, Juhyeok; Park, Jae Sun; Lee, S. G.; Lee, J. H.; Lee, Seung Hun; Hong, Suk-Ho; Choe, Wonho


    Experiments with a small amount of Ar gas injection as a trace impurity were conducted in the Korea Superconducting Tokamak Advanced Research (KSTAR) H-mode plasma ({{B}\\text{T}}   =  2.8 T, {{I}\\text{P}}   =  0.6 MA, and {{P}\\text{NBI}}   =  4.0 MW). 170 GHz electron cyclotron resonance heating (ECH) at 600 and 800 kW was focused along the mid-plane with a fixed major radial position of R   =  1.66 m. The emissivity of the Ar16+ (3.949 {\\mathring{\\text{A}}} ) and Ar15+ (353.860 {\\mathring{\\text{A}}} ) spectral lines were measured by x-ray imaging crystal spectroscopy (XICS) and a vacuum UV (VUV) spectrometer, respectively. ECH reduces the peak Ar15+ emission and increases the Ar16+ emission, an effect largest with 800 kW. The ADAS-SANCO impurity transport code was used to evaluate the Ar transport coefficients. It was found that the inward convective velocity found in the plasma core without ECH was decreased with ECH, while diffusion remained approximately constant resulting in a less-peaked Ar density profile. Theoretical results from the NEO code suggest that neoclassical transport is not responsible for the change in transport, while the microstability analysis using GKW predicts a dominant ITG mode during both ECH and non-ECH plasmas.

  1. Dynamics and stability of divertor detachment in H-mode plasmas on JET

    Field, A. R.; Balboa, I.; Drewelow, P.; Flanagan, J.; Guillemaut, C.; Harrison, J. R.; Huber, A.; Huber, V.; Lipschultz, B.; Matthews, G.; Meigs, A.; Schmitz, J.; Stamp, M.; Walkden, N.; contributors, JET


    The dynamics and stability of divertor detachment in {{{N}}}2 seeded, type-I, ELMy H-mode plasmas with dominant NBI heating in the JET ITER-like wall device is studied by means of an integrated analysis of diagnostic data from several systems, classifying data relative to the ELM times. It is thereby possible to study the response of the detachment evolution to the control parameters (SOL input power, upstream density and impurity fraction) prevailing during the inter-ELM periods and the effect of ELMs on the detached divertor. A relatively comprehensive overview is achieved, including the interaction with the targets at various stages of the ELM cycle, the role of ELMs in affecting the detachment process and the overall performance of the scenario. The results are consistent with previous studies in devices with an ITER-like, metal wall, with the important advance of distinguishing data from intra- and inter-ELM periods. Operation without significant degradation of the core confinement can be sustained in the presence of strong radiation from the x-point region (MARFE).

  2. Investigation of inter-ELM ion heat transport in the H-mode pedestal of ASDEX Upgrade plasmas

    Viezzer, E.; Fable, E.; Cavedon, M.; Angioni, C.; Dux, R.; Laggner, F. M.; Bernert, M.; Burckhart, A.; McDermott, R. M.; Pütterich, T.; Ryter, F.; Willensdorfer, M.; Wolfrum, E.; the ASDEX Upgrade Team; the EUROfusion MST1 Team


    The ion heat transport in the pedestal of H-mode plasmas is investigated in various H-mode discharges with different pedestal ion collisionalities. Interpretive modelling suggests that in all analyzed discharges the ion heat diffusivity coefficient, {χ\\text{i}} , in the pedestal is close to the neoclassical prediction within the experimental uncertainties. The impact of changing the deposition location of the electron cyclotron resonance heating on the ion heat transport has been studied. The effect on the background profiles is small. The pre-ELM (edge localized modes) edge profiles as well as the behaviour of the electron temperature and density, ion temperature and impurity toroidal rotation during the ELM cycle are very similar in discharges with on- and off-axis ECRH heating. No significant deviation of {χ\\text{i}} from neoclassics is observed when changing the ECRH deposition location to the plasma edge.

  3. Improved confinement in high-density H-modes via modification of the plasma boundary with lower hybrid wavesa)

    Terry, J. L.; Reinke, M. L.; Hughes, J. W.; LaBombard, B.; Theiler, C.; Wallace, G. M.; Baek, S. G.; Brunner, D.; Churchill, R. M.; Edlund, E.; Ennever, P.; Faust, I.; Golfinopoulos, T.; Greenwald, M.; Hubbard, A. E.; Irby, J.; Lin, Y.; Parker, R. R.; Rice, J. E.; Shiraiwa, S.; Walk, J. R.; Wukitch, S. J.; Xu, P.


    Injecting Lower Hybrid Range of Frequency (LHRF) waves into Alcator C-Mod's high-density H-mode plasmas has led to enhanced global energy confinement by increasing pedestal temperature and pressure gradients, decreasing the separatrix density, modifying the pedestal radial electric field and rotation, and decreasing edge turbulence. These experiments indicate that edge LHRF can be used as an actuator to increase energy confinement via modification of boundary quantities. H98-factor increases of up to ˜35% (e.g., H98 from 0.75 to 1.0) are seen when moderate amounts of LH power (PLH/Ptot ˜ 0.15) are applied to H-modes of densities n ¯ e ˜ 3 × 1020 m-3, corresponding to values ˜0.5 of the Greenwald density. However, the magnitude of the improvement is reduced if the confinement quality of the target H-mode plasma is already good (i.e., H98target ˜ 1). Ray-tracing modeling and accessibility calculations for the LH waves indicate that they do not penetrate to the core. The LHRF power appears to be deposited in plasma boundary region, with a large fraction of the injected power increment appearing promptly on the outer divertor target. There is no evidence that the LH waves are driving current in these plasmas. The LHRF-actuated improvements are well correlated with suppressed pedestal density fluctuations in the 100-300 kHz range. There is also a correlation between the improved confinement and a drop in separatrix density, a correlation that is consistent with previous H-mode results with no LHRF.

  4. Comparisons of Predicted Plasma Performance in ITER H-mode Plasmas with Various Mixes of External He

    R.V. Budny


    Performance in H-mode DT plasmas in ITER with various choices of heating systems are predicted and compared. Combinations of external heating by Negative Ion Neutral Beam Injection (NNBI), Ion Cyclotron Range of Frequencies (ICRF), and Electron Cyclotron Heating (ECH) are assumed. Scans with a range of physics assumptions about boundary temperatures in the edge pedestal, alpha ash transport, and toroidal momentum transport are used to indicate effects of uncertainties. Time-dependent integrated modeling with the PTRANSP code is used to predict profiles of heating, beam torque, and plasma profiles. The GLF23 model is used to predict temperature profiles. Either GLF23 or the assumption of a constant ratio for χø/χi is used to predict toroidal rotation profiles driven by the beam torques. Large differences for the core temperatures are predicted with different mixes of the external heating during the density and current ramp-up phase, but the profiles are similar during the flattop phase. With χø/χi = 0.5, the predicted toroidal rotation is relatively slow and the flow shear implied by the pressure, toroidal rotation, and neoclassical poloidal rotation are not sufficient to cause significant changes in the energy transport or steady state temperature profiles. The GLF23-predicted toroidal rotation is faster by a factor of six, and significant flow shear effects are predicted.

  5. Coupled core-SOL modelling of W contamination in H-mode JET plasmas with ITER-like wall

    Parail, V., E-mail: [CCFE Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Corrigan, G.; Da Silva Aresta Belo, P. [CCFE Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); De La Luna, E. [Laboratorio Nacional de Fusion, Madrid (Spain); Harting, D. [CCFE Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Koechl, F. [Atominstitut, TU Wien, 1020 Vienna (Austria); Koskela, T. [Aalto University, Department of Applied Physics, P.O. Box 14100, FIN-00076 Aalto (Finland); Meigs, A.; Militello-Asp, E.; Romanelli, M. [CCFE Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Tsalas, M. [FOM Institute DIFFER, P.O. Box 1207, NL-3430 BE Nieuwegein (Netherlands)


    The influence of the ITER-like Wall (ILW) with divertor target plate made of tungsten (W), on plasma performance in JET H-mode is being investigated since 2011 (see F. Romanelli and references therein). One of the key issues in discharges with low level of D fuelling is observed accumulation of W in the plasma core, which leads to a reduction in plasma performance. To study the interplay between W sputtering on the target plate, penetration of W through the SOL and edge transport barrier (ETB) and its further accumulation in plasma core predictive modelling was launched using a coupled 1.5D core and 2D SOL code JINTRAC (Romanelli, 2014; Cenacchi and Taroni, 1988; Taroni et al., 1992; Wiesen et al., 2006). Simulations reveal the important role of ELMs in W sputtering and plasma density control. Analyses also confirm pivotal role played by the neo-classical pinch of heavy impurities within the ETB.

  6. Access to a New Plasma Edge State with High Density and Pressures using Quiescent H-mode

    Solomon, Wayne M. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Snyder, P. B. [General Atomics, San Diego, CA (United States); Burrell, K. H. [General Atomics, San Diego, CA (United States); Fenstermacher, M. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Garofalo, A. M. [General Atomics, San Diego, CA (United States); Grierson, B. A. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Loarte, A. [ITER Organization, St. Paul Lez Durance (France); McKee, G. R. [Univ. of Wisconsin, Madison, WI (United States); Nazikian, R [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Osborne, T. H. [General Atomics, San Diego, CA (United States)


    A path to a new high performance regime has been discovered in tokamaks that could improve the attractiveness of a fusion reactor. Experiments on DIII-D using a quiescent H-mode edge have navigated a valley of improved edge peeling-ballooning stability that opens up with strong plasma shaping at high density, leading to a doubling of the edge pressure over standard edge localized mode (ELM)ing H-mode at these parameters. The thermal energy confinement time increases both as a result of the increased pedestal height and improvements in the core transport and reduced low-k turbulence. Calculations of the pedestal height and width as a function of density using constraints imposed by peeling-ballooning and kinetic-ballooning theory are in quantitative agreement with the measurements.

  7. Modelling of transitions between L- and H-mode in JET high plasma current plasmas and application to ITER scenarios including tungsten behaviour

    Koechl, F.; Loarte, A.; Parail, V.; Belo, P.; Brix, M.; Corrigan, G.; Harting, D.; Koskela, T.; Kukushkin, A. S.; Polevoi, A. R.; Romanelli, M.; Saibene, G.; Sartori, R.; Eich, T.; Contributors, JET


    The dynamics for the transition from L-mode to a stationary high Q DT H-mode regime in ITER is expected to be qualitatively different to present experiments. Differences may be caused by a low fuelling efficiency of recycling neutrals, that influence the post transition plasma density evolution on the one hand. On the other hand, the effect of the plasma density evolution itself both on the alpha heating power and the edge power flow required to sustain the H-mode confinement itself needs to be considered. This paper presents results of modelling studies of the transition to stationary high Q DT H-mode regime in ITER with the JINTRAC suite of codes, which include optimisation of the plasma density evolution to ensure a robust achievement of high Q DT regimes in ITER on the one hand and the avoidance of tungsten accumulation in this transient phase on the other hand. As a first step, the JINTRAC integrated models have been validated in fully predictive simulations (excluding core momentum transport which is prescribed) against core, pedestal and divertor plasma measurements in JET C-wall experiments for the transition from L-mode to stationary H-mode in partially ITER relevant conditions (highest achievable current and power, H 98,y ~ 1.0, low collisionality, comparable evolution in P net/P L-H, but different ρ *, T i/T e, Mach number and plasma composition compared to ITER expectations). The selection of transport models (core: NCLASS  +  Bohm/gyroBohm in L-mode/GLF23 in H-mode) was determined by a trade-off between model complexity and efficiency. Good agreement between code predictions and measured plasma parameters is obtained if anomalous heat and particle transport in the edge transport barrier are assumed to be reduced at different rates with increasing edge power flow normalised to the H-mode threshold; in particular the increase in edge plasma density is dominated by this edge transport reduction as the calculated neutral influx across the

  8. Characteristics of edge pedestals in LHW and NBI heated H-mode plasmas on EAST

    Zang, Q.; Wang, T.; Liang, Y.; Sun, Y.; Chen, H.; Xiao, S.; Han, X.; Hu, A.; Hsieh, C.; Zhou, H.; Zhao, J.; Zhang, T.; Gong, X.; Hu, L.; Liu, F.; Hu, C.; Gao, X.; Wan, B.; the EAST Team


    By using the recently developed Thomson scattering diagnostic, the pedestal structure of the H-mode with neutral beam injection (NBI) or/and lower hybrid wave (LHW) heating on EAST (Experimental Advanced Superconducting Tokamak) is analyzed in detail. We find that a higher ratio of the power of the NBI to the total power of the NBI and the lower hybrid wave (LHW) will produce a large and regular different edge-localized mode (ELM), and a lower ratio will produce a small and irregular ELM. The experiments show that the mean pedestal width has good correlation with β \\text{p,\\text{ped}}0.5 , The pedestal width appears to be wider than that on other similar machines, which could be due to lithium coating. However, it is difficult to draw any conclusion of correlation between ρ * and the pedestal width for limited ρ * variation and scattered distribution. It is also found that T e/\

  9. Local Physics Basis of Confinement Degradation in JET ELMy H-Mode Plasmas and Implications for Tokamak Reactors

    Budny, R.V.; Alper, B.; Borba, D.; Cordey, J.G.; Ernst, D.R.; Gowers, C. [and others


    First results of gyrokinetic analysis of JET [Joint European Torus] ELMy [Edge Localized Modes] H-mode [high-confinement modes] plasmas are presented. ELMy H-mode plasmas form the basis of conservative performance predictions for tokamak reactors of the size of ITER [International Thermonuclear Experimental Reactor]. Relatively high performance for long duration has been achieved and the scaling appears to be favorable. It will be necessary to sustain low Z(subscript eff) and high density for high fusion yield. This paper studies the degradation in confinement and increase in the anomalous heat transport observed in two JET plasmas: one with an intense gas puff and the other with a spontaneous transition between Type I to III ELMs at the heating power threshold. Linear gyrokinetic analysis gives the growth rate, gamma(subscript lin) of the fastest growing modes. The flow-shearing rate omega(subscript ExB) and gamma(subscript lin) are large near the top of the pedestal. Their ratio decreases approximately when the confinement degrades and the transport increases. This suggests that tokamak reactors may require intense toroidal or poloidal torque input to maintain sufficiently high |gamma(subscript ExB)|/gamma(subscript lin) near the top of the pedestal for high confinement.

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

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


    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.

  11. Transport hysteresis of core plasma, isotope effect, and H-mode physics

    Itoh, S.-I.; Itoh, K.; Inagaki, S.


    This article assesses the understanding of and impact by the hysteresis in transport relation. The rapid changes of fluxes compared to slow changes of plasma parameters are overviewed for both edge barrier and core plasmas. The theoretical approaches to understanding the direct influence of heating power on turbulent transport are addressed. Based on this new theoretical framework, the ‘isotope effect’ of plasma confinement time is discussed. A trial explanation is given for this unresolved mystery in plasma confinement. The advanced data analysis method to research the hysteresis in gradient-flux relation is explained.

  12. The quiescent H-mode regime for high performance edge localized mode-stable operation in future burning plasmas

    Garofalo, A. M., E-mail:; Burrell, K. H.; Meneghini, O.; Osborne, T. H.; Paz-Soldan, C.; Smith, S. P.; Snyder, P. B.; Turnbull, A. D. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Eldon, D.; Grierson, B. A.; Solomon, W. M. [Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543-0451 (United States); Hanson, J. M. [Columbia University, 2960 Broadway, New York, New York 10027-6900 (United States); Holland, C. [University of California San Diego, 9500 Gilman Dr., La Jolla, California 92093-0417 (United States); Huijsmans, G. T. A.; Liu, F.; Loarte, A. [ITER Organization, Route de Vinon sur Verdon, 13067 St Paul Lez Durance (France); Zeng, L. [University of California Los Angeles, P.O. Box 957099, Los Angeles, California 90095-7099 (United States)


    For the first time, DIII-D experiments have achieved stationary quiescent H-mode (QH-mode) operation for many energy confinement times at simultaneous ITER-relevant values of beta, confinement, and safety factor, in an ITER-like shape. QH-mode provides excellent energy confinement, even at very low plasma rotation, while operating without edge localized modes (ELMs) and with strong impurity transport via the benign edge harmonic oscillation (EHO). By tailoring the plasma shape to improve the edge stability, the QH-mode operating space has also been extended to densities exceeding 80% of the Greenwald limit, overcoming the long-standing low-density limit of QH-mode operation. In the theory, the density range over which the plasma encounters the kink-peeling boundary widens as the plasma cross-section shaping is increased, thus increasing the QH-mode density threshold. The DIII-D results are in excellent agreement with these predictions, and nonlinear magnetohydrodynamic analysis of reconstructed QH-mode equilibria shows unstable low n kink-peeling modes growing to a saturated level, consistent with the theoretical picture of the EHO. Furthermore, high density operation in the QH-mode regime has opened a path to a new, previously predicted region of parameter space, named “Super H-mode” because it is characterized by very high pedestals that can be more than a factor of two above the peeling-ballooning stability limit for similar ELMing H-mode discharges at the same density.

  13. Tungsten transport and sources control in JET ITER-like wall H-mode plasmas

    Fedorczak, N., E-mail: [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Monier-Garbet, P. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Pütterich, T. [MPI für Plasmaphysik, EURATOM Association, Boltzmannstrasse 2, 85748 Garching (Germany); Brezinsek, S. [Institute of Energy and Climate Research, Forschungszentrum Jlich, Assoc EURATOM-FZJ, Jlich (Germany); Devynck, P.; Dumont, R.; Goniche, M.; Joffrin, E. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Lerche, E. [Association EURATOM-Belgian State, LPP-ERM-KMS, TEC partner, Brussels (Belgium); Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Lipschultz, B. [York Plasma Institute, University of York, Heslington, York YO10 5DD (United Kingdom); Luna, E. de la [Laboratorio Nacional de Fusin, Asociacin EURATOM/CIEMAT, 28040 Madrid (Spain); Maddison, G. [Culham Centre for Fusion Energy, EURATOM-CCFE Association, Abingdon (United Kingdom); Maggi, C. [MPI für Plasmaphysik, EURATOM Association, Boltzmannstrasse 2, 85748 Garching (Germany); Matthews, G. [Culham Centre for Fusion Energy, EURATOM-CCFE Association, Abingdon (United Kingdom); Nunes, I. [Istituto de plasmas e fusao nuclear, Lisboa (Portugal); Rimini, F. [Culham Centre for Fusion Energy, EURATOM-CCFE Association, Abingdon (United Kingdom); Solano, E.R. [Laboratorio Nacional de Fusin, Asociacin EURATOM/CIEMAT, 28040 Madrid (Spain); Tamain, P. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Tsalas, M. [Association EURATOM-Hellenic Republic, NCSR Demokritos 153 10, Attica (Greece); Vries, P. de [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France)


    A set of discharges performed with the JET ITER-like wall is investigated with respect to control capabilities on tungsten sources and transport. In attached divertor regimes, increasing fueling by gas puff results in higher divertor recycling ion flux, lower divertor tungsten source, higher ELM frequency and lower core plasma radiation, dominated by tungsten ions. Both pedestal flushing by ELMs and divertor screening (including redeposition) are possibly responsible. For specific scenarios, kicks in plasma vertical position can be employed to increase the ELM frequency, which results in slightly lower core radiation. The application of ion cyclotron radio frequency heating at the very center of the plasma is efficient to increase the core electron temperature gradient and flatten electron density profile, resulting in a significantly lower central tungsten peaking. Beryllium evaporation in the main chamber did not reduce the local divertor tungsten source whereas core radiation was reduced by approximately 50%.

  14. Alpha Heating in ITER L-mode and H-mode Plasma

    R.V. Budny


    There are many uses of predictions of ITER plasma performance. One is assessing requirements of different plasma regimes. For instance, what current drive and control are needed for steady state. The heating, current drive, and torque systems planned for initial DT operation are negative ion neutral beam injection (NB), ion cyclotron resonance (IC), and electron cyclotron resonance (EC). Which combinations of heating are optimal. What are benefits of the torques, current drive, and fueling using NB. What are the shine-through power and optimum voltage for the NB? What are optimal locations and aiming of the EC launchers? Another application is nuclear licensing (e.g. System integrity, how many neutrons).

  15. Turbulence at the transition to the high density H-mode in Wendelstein 7-AS plasmas

    Basse, N.P.; Zoletnik, S.; Baumel, S.


    Recently a new improved confinement regime was found in the Wendelstein 7-AS (W7-AS) stellarator (Renner H. et al 1989 Plasma Phys. Control. Fusion 31 1579). The discovery of this high density high confinement mode (HDH-mode) was facilitated by the installation of divertor modules. In this paper...... of the fluctuation level associated with the transition from NC- to HDH-mode. Correlation calculations on a 20 mus timescale between magnetic and density fluctuations lead to the result that the fluctuations are correlated in NC- but not in HDH-mode. Finally, a comparative analysis between the enhanced D-alpha H...

  16. Impact of localized gas injection on ICRF coupling and SOL parameters in JET-ILW H-mode plasmas

    Lerche, E., E-mail: [LPP-ERM-KMS, TEC Partner, 1000 Brussels (Belgium); CCFE, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Goniche, M. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Jacquet, P. [CCFE, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Van Eester, D. [LPP-ERM-KMS, TEC Partner, 1000 Brussels (Belgium); Bobkov, V. [Max-Planck-Institut für Plasmaphysik, Garching (Germany); Colas, L. [CCFE, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Czarnecka, A. [IPPLM, 01-497 Warsaw (Poland); Brezinsek, S. [Forschungszentrum Jülich, Institute of Energy Research, Jülich (Germany); Brix, M. [CCFE, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Crombe, K. [LPP-ERM-KMS, TEC Partner, 1000 Brussels (Belgium); Graham, M. [CCFE, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Groth, M. [Aalto University, 02015 Espoo (Finland); Monakhov, I. [CCFE, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Mathurin, T. [École des Mines de Paris, 75006 Paris (France); Matthews, G. [CCFE, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Meneses, L. [Instituto de Plasma e Fusão Nuclear, Instituto Superior Técnico, Lisbon (Portugal); Noble, C. [CCFE, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Petrzilka, V. [Institute of Plasma Physics, Prague (Czech Republic); Rimini, F.; Shaw, A. [CCFE, Culham Science Centre, Abingdon OX14 3DB (United Kingdom)


    Recent JET-ILW [1,2] experiments reiterated the importance of tuning the plasma fuelling in order to optimize ion cyclotron resonance frequency (ICRF) heating in high power H-mode discharges. By fuelling the plasma from gas injection modules (GIMs) located in the mid-plane and on the top of the machine instead of adopting the more standardly used divertor GIMs, a considerable increase of the ICRF antenna coupling resistances was achieved with moderate gas injection rates (<1.5 × 10{sup 22} e/s). This effect is explained by an increase of the scrape-off-layer density in front of the antennas when mid-plane and top fuelling is used. By distributing the gas injection to optimize the coupling of all ICRF antenna arrays simultaneously, a substantial increase in the ICRF power capability and reliability was attained. Although similar core/pedestal plasma properties were observed for the different injection cases, the experiments indicate that the RF-induced impurity sources are reduced when switching from divertor to main chamber gas injection.

  17. Influence of gas puff location on the coupling of lower hybrid waves in JET ELMy H-mode plasmas

    Ekedahl, A. [CEA, IRFM, France; Petrzilka, V. [Assoc. Euratom-IPP.CR, Czech Republic; Baranov, Y. [EURATOM / UKAEA, UK; Brix, M [UKAEA Fusion, Culham UK; Goniche, M. [CEA, IRFM, France; Jacquet, P. [EURATOM / UKAEA, Abingdon, UK; Kirov, K K [Association EURATOM-CCFE, Abingdon, UK; Klepper, C Christopher [ORNL; Mailloux, J. [EURATOM / UKAEA, UK; Mayoral, M.-L. [EURATOM / UKAEA, UK; Nave, M. F. F. [Association EURATOM/IST, Lisbon, Portugal; Ongena, J. [Laboratory for Plasma Physics-ERM/KMS (LPP-ERM/KMS), Brussels, Belgium


    Reliable coupling of the lower hybrid current drive (LHCD) to H-mode plasmas in JET is made feasible through a dedicated gas injection system, located at the outer wall and magnetically connected to the antenna (Pericoli Ridolfini et al 2004 Plasma Phys. Control. Fusion 46 349, Ekedahl et al 2005 Nucl. Fusion 45 351, Ekedahl et al 2009 Plasma Phys. Control. Fusion 51 044001). An experiment was carried out in JET in order to investigate whether a gas injection from the top of the torus, as is foreseen for the main gas injection in ITER, could also provide good coupling of the LH waves if magnetically connected to the antenna. The results show that a top gas injection was not efficient for providing a reliable LHCD power injection, in spite of being magnetically connected and in spite of using almost twice the amount of gas flow compared with the dedicated outer mid-plane gas puffing system. A dedicated gas injection system, set in the outer wall and magnetically connected to the LHCD antenna, is therefore recommended in order to provide the reliable coupling conditions for an LHCD antenna in ITER.

  18. Impact of divertor geometry on radiative divertor performance in JET H-mode plasmas

    Jaervinen, A. E.; Brezinsek, S.; Giroud, C.; Groth, M.; Guillemaut, C.; Belo, P.; Brix, M.; Corrigan, G.; Drewelow, P.; Harting, D.; Huber, A.; Lawson, K. D.; Lipschultz, B.; Maggi, C. F.; Matthews, G. F.; Meigs, A. G.; Moulton, D.; Stamp, M. F.; Wiesen, S.; Contributors, JET


    Radiative divertor operation in JET high confinement mode plasmas with the ITER-like wall has been experimentally investigated and simulated with EDGE2D-EIRENE in horizontal and vertical low field side (LFS) divertor configurations. The simulations show that the LFS divertor heat fluxes are reduced with N2-injection in similar fashion in both configurations, qualitatively consistent with experimental observations. The simulations show no substantial difference between the two configurations in the reduction of the peak LFS heat flux as a function of divertor radiation, nitrogen concentration, or pedestal Zeff. Consistently, experiments show similar divertor radiation and nitrogen injection levels for similar LFS peak heat flux reduction in both configurations. Nevertheless, the LFS strike point is predicted to detach at 20% lower separatrix density in the vertical than in the horizontal configuration. However, since the peak LFS heat flux in partial detachment in the vertical configurations is shifted towards the far scrape-off layer (SOL), the simulations predict no benefit in the reduction of LFS peak heat flux for a given upstream density in the vertical configuration relative to a horizontal one. A factor of 2 reduction of deuterium ionization source inside the separatrix is observed in the simulations when changing to the vertical configuration. The simulations capture the experimentally observed particle and heat flux reduction at the LFS divertor plate in both configurations, when adjusting the impurity injection rate to reproduce the measured divertor radiation. However, the divertor D α -emissions are underestimated by a factor of 2-5, indicating a short-fall in radiation by the fuel species. In the vertical configuration, detachment is experimentally measured and predicted to start next to the strike point, extending towards the far SOL with increasing degree of detachment. In contrast, in the horizontal configuration, the entire divertor particle flux

  19. Experimental validation of non-uniformity effect of the radial electric field on the edge transport barrier formation in JT-60U H-mode plasmas

    Kamiya, Kensaku; Itoh, Kimitaka; Itoh, Sanae-I.; JT-60 Team


    Non-uniformity effects of the edge radial electric field (Er) on the edge transport barriers (ETBs) formation have been identified with high-spatiotemporal resolution spectroscopic measurement. We found the decisive importance of Er-curvature (2nd derivative of Er) on ETB formation during ELM-free H-mode phase, but there is only a low correlation with the Er-shear (1st derivative of Er) value at the peak of normalized ion temperature gradient in the pedestal region. Observation of a uniform toroidal MHD oscillation (i.e. Geodesic Acoustic Mode having toroidal mode number n = 0) during the ETBs formation can also support the hypothesis of turbulence suppression in association with Zonal-flow (and/or Er-curvature). Furthermore, in the ELMing phase, the effect of curvature is also quantified in terms of the relationship between pedestal width and thickness of the layer of inhomogeneous Er. This is the fundamental basis to understand the structure of transport barriers in fusion plasmas. Authors acknowledge the partial support by Grant-in-Aid for Scientific Research (15K06657, 15H02155, 16H02442) and collaboration programmes between QST and universities and of the RIAM of Kyushu University, and by Asada Science Foundation.

  20. Characteristics of toroidal rotation and ion temperature pedestals between ELM bursts in KSTAR H-mode plasmas

    Ko, S. H.; Kwon, J. M.; Ko, W. H.; Kim, S. S.; Jhang, H.; Terzolo, L.


    Steep pedestal profiles of ion temperature (Ti) and toroidal rotation ( V ϕ ) are routinely observed in neutral beam injection (NBI)-heated KSTAR H-mode plasmas [W. H. Ko et al., Nucl. Fusion 55, 083013 (2015)]. In this work, we report a result of detailed analysis of pedestal characteristics. By analyzing a set of data with different experimental conditions, we show that Ti and V ϕ pedestals are coupled to each other and correlation between them becomes stronger when NBI-torque is lower. This suggests the existence of intrinsic toroidal torque in the pedestal. Based on a 1D transport analysis, we find that the prevalence of residual micro-turbulences is necessary to explain momentum transport in the pedestal. The estimated strength of intrinsic torque is shown to be comparable to that from a 2.7 MW NBI source. Finally, we show that non-diffusive momentum flux is indispensable to explain momentum transport in the pedestal, and a residual stress model fits the observed momentum flux reasonably.

  1. Impact of nitrogen seeding on confinement and power load control of a high-triangularity JET ELMy H-mode plasma with a metal wall

    Giroud, C.; Maddison, G. P.; Jachmich, S.; Rimini, F.; Beurskens, M. N. A.; Balboa, I.; Brezinsek, S.; Coelho, R.; Coenen, J. W.; Frassinetti, L.; Joffrin, E.; Oberkofler, M.; Lehnen, M.; Liu, Y.; Marsen, S.; McCormick, K.; Meigs, A.; Neu, R.; Sieglin, B.; van Rooij, G. J.; Arnoux, G.; Belo, P.; Brix, M.; Clever, M.; Coffey, I.; Devaux, S.; Douai, D.; Eich, T.; Flanagan, J.; S. Grünhagen,; Huber, A.; Kempenaars, M.; Kruezi, U.; Lawson, K.; Lomas, P.; Lowry, C.; Nunes, I.; Sirinnelli, A.; Sips, A.C.C.; Stamp, M.; Wiesen, S.; JET-EFDA Contributors,


    This paper reports the impact on confinement and power load of the high-shape 2.5 MA ELMy H-mode scenario at JET of a change from all carbon plasma-facing components to an all metal wall. In preparation to this change, systematic studies of power load reduction and impact on confinement as a result

  2. Investigation of reactive plasma species created in SO2 by an inductively coupled RF discharge in E- and H-mode

    Zaplotnik, Rok; Vesel, Alenka; Mozetic, Miran


    Optical emission spectroscopy (OES) and mass spectrometry were used to investigate the gas phase and surface reactions in inductively coupled SO2 plasma at various radiofrequency discharge powers up to 1000 W and gas pressures from 30 to 100 Pa. At such conditions, the plasma was created either in E- or in H-mode. In the E-mode, extensive radiation in the UV range was observed due to transitions of SO2 and SO molecules to the ground electronic states, whereas the other spectral features were marginal. At elevated powers, an abrupt transition to the H-mode occurred, where the total radiation increased for several orders of magnitude. Strong hysteresis was observed in the behaviour of all OES spectral features at the transitions between the E- and H-modes. In the H-mode, the atomic lines prevailed because of the relaxation of highly excited O and S atoms to the lower excited states, indicating high density of atoms. UV continuum was very weak and governed only by transitions of the SO radicals to the ground state. Thus, it was concluded that in the E-mode, predominantly SO and O radicals are formed during the partial dissociation of SO2 molecules, whereas in the H-mode, high dissociation to S and O atoms occurred, leading to the negligible concentration of SO2. However, in the flowing afterglow, the final gas composition was predominantly always SO2. The concentration of O2 was only approximately 3%, whereas the concentration of SO3 was marginal. This was explained by the recombination of the reactive plasma species formed in the plasma back to SO2 molecules on the surfaces of the remote plasma reactor.

  3. Metal impurity transport control in JET H-mode plasmas with central ion cyclotron radiofrequency power injection

    Valisa, M.; Carraro, L.; Predebon, I.


    The scan of ion cyclotron resonant heating (ICRH) power has been used to systematically study the pump out effect of central electron heating on impurities such as Ni and Mo in H-mode low collisionality discharges in JET. The transport parameters of Ni and Mo have been measured by introducing a t...

  4. Comparison of H-mode plasma simulations using toroidal velocity models depending on plasma current density and ion temperature in presence of an ITB

    Boonyarit Chatthong


    Full Text Available Two different approaches for predicting plasma toroidal velocity (v are developed and used in self-consistent simulations of H-mode plasmas with the presence of ITB using BALDUR integrated predictive modelling code. In the first approach, the toroidal velocity depends on the plasma current density; while in the second approach the toroidal velocity is directly proportional to the ion temperature. The profile of v is used to calculate the ExB flow shear which is a main mechanism for plasma transport suppression, leading to the ITB formation. In all simulations, the core transport model is a combination of NCLASS neoclassical transport and semi-empirical Mixed Bohm/gyro-Bohm model that includes the ITB effects. The boundary condition is set at top of the pedestal and is estimated using a pedestal model based on a combination of magnetic and flow shear stabilization pedestal width scaling and an infinite-n ballooning pressure gradient. Two toroidal velocity models are used to simulate the time evolution of plasma temperature and density profiles of 10 JET discharges. The root mean square error (RMSE is used to compare simulation results of those 10 JET discharges with experimental data. It is found that RMSE of Ti , Te , ne are 28.1%, 31.8%, and 15.0% for the first toroidal velocity model and 25.5%, 30.2%, and 15.1% for the second toroidal velocity model, respectively. Furthermore, this suite of codes is used to predict the ITER performance under standard type I ELMy H-mode. It is found that the simulation yields formation of a narrow ITB near r/a = 0.7 in the simulation using the current density dependent model and a wide ITB from r/a = 0.5 to 0.8 in the simulation using the ion temperature dependent model. The average of central ion temperature, total fusion power output and alpha power are predicted to be 36 keV, 159 MW and 492 MW for the current density dependent model and 49 keV, 218 MW and 786 MW for the ion temperature dependent

  5. Impact of nitrogen seeding on confinement and power load control of a high-triangularity JET ELMy H-mode plasma with a metal wall

    Giroud, C; Jachmich, S; Rimini, F; Beurskens, M N A; Balboa, I; Brezinsek, S; Coelho, R; Coenen, J W; Frassinetti, L; Joffrin, E; Oberkofler, M; Lehnen, M; Liu, Y; Marsen, S; K, K McCormick; Meigs, A; Neu, R; Sieglin, B; van Rooij, G; Arnoux, G; Belo, P; Brix, M; Clever, M; Coffey, I; Devaux, S; Douai, D; Eich, T; Flanagan, J; Grunhagen, S; Huber, A; Kempenaars, M; Kruezi, U; Lawson, K; Lomas, P; Lowry, C; Nunes, I; Sirinnelli, A; Sips, A C C; Stamp, M; Wiesen, S; contributors, JET-EFDA


    This paper reports the impact on confinement and power load of the high-shape 2.5MA ELMy H-mode scenario at JET of a change from an all carbon plasma facing components to an all metal wall. In preparation to this change, systematic studies of power load reduction and impact on confinement as a result of fuelling in combination with nitrogen seeding were carried out in JET-C and are compared to their counterpart in JET with a metallic wall. An unexpected and significant change is reported on the decrease of the pedestal confinement but is partially recovered with the injection of nitrogen.

  6. Three-dimensional simulation of H-mode plasmas with localized divertor impurity injection on Alcator C-Mod using the edge transport code EMC3-EIRENE

    Lore, J. D., E-mail: [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Reinke, M. L.; Lipschultz, B. [York Plasma Institute, Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom); Brunner, D.; LaBombard, B.; Terry, J. [Plasma Science and Fusion Center, MIT, Cambridge, Massachusetts 02139 (United States); Pitts, R. A. [ITER Organization, Route de Vinon-sur-Verdon, CS 90046 - 13067 Saint Paul Lez Durance Cedex (France); Feng, Y. [Max Planck Institute for Plasma Physics, Greifswald (Germany)


    Experiments in Alcator C-Mod to assess the level of toroidal asymmetry in divertor conditions resulting from poloidally and toroidally localized extrinsic impurity gas seeding show a weak toroidal peaking (∼1.1) in divertor electron temperatures for high-power enhanced D-alpha H-mode plasmas. This is in contrast to similar experiments in Ohmically heated L-mode plasmas, which showed a clear toroidal modulation in the divertor electron temperature. Modeling of these experiments using the 3D edge transport code EMC3-EIRENE [Y. Feng et al., J. Nucl. Mater. 241, 930 (1997)] qualitatively reproduces these trends, and indicates that the different response in the simulations is due to the ionization location of the injected nitrogen. Low electron temperatures in the private flux region (PFR) in L-mode result in a PFR plasma that is nearly transparent to neutral nitrogen, while in H-mode the impurities are ionized in close proximity to the injection location, with this latter case yielding a largely axisymmetric radiation pattern in the scrape-off-layer. The consequences for the ITER gas injection system are discussed. Quantitative agreement with the experiment is lacking in some areas, suggesting potential areas for improving the physics model in EMC3-EIRENE.

  7. Improved confinement in ELM-suppressed high-density H-modes at the ITER field via modification of the plasma boundary with Lower Hybrid RF

    Terry, J. L.


    Injecting Lower Hybrid (LH) power into Alcator C-Mod's high-density H-mode plasmas has enhanced global confinement by increasing pedestal temperature gradients, modifying edge rotation, and decreasing edge and SOL turbulence. These new experiments indicate that edge LHRF can be used as a tool to increase confinement via direct modification of boundary quantities. Ray-tracing modeling and accessibility calculations for the LH waves indicate that the LH waves do not penetrate to regions inside the top of the pedestal and are not driving current in these plasmas; instead the LH power modifies the boundary conditions. When moderate amounts of LH power (PLH/Ptot = 20%) are applied to high-density EDA H-modes (neo = 3.5×1020 m-3) , we observe the following effects: edge/SOL fluctuation power decreases by roughly an order of magnitude; pedestal temperature gradients are increased; global energy confinement time and H-factor increase by 30-40% (H98 from 0.7 to 1.0); co-current core and pedestal rotation velocities increase; power to the (outer) divertor target increases promptly with an increment that is roughly 1/2 of the injected LH power, qualitatively consistent with the inaccessibility of the LH waves; and the central frequency of the edge-localized Quasi-Coherent Mode down-shifts and becomes much more coherent. These H-mode confinement improvements brought about by the edge LHRF are the result of changes in the pedestal (e.g. changes in rotation/shear and increased pedestal temperature gradients), with no substantial change in peaking of core density or temperature profiles. There is not perfect correlation with edge turbulence suppression, indicating that the turbulence decrease may be a necessary, but not sufficient, condition for the pedestal and confinement improvements. Supported by US DoE Awards DE-FC02-99ER54512 and DE-AC02-09CH11466.

  8. Comparative analysis of core heat transport of JET high density H-mode plasmas in carbon wall and ITER-like wall

    Kim, Hyun-Tae; Romanelli, M.; Voitsekhovitch, I.; Koskela, T.; Conboy, J.; Giroud, C.; Maddison, G.; Joffrin, E.; contributors, JET


    A consistent deterioration of global confinement in H-mode experiments has been observed in JET [1] following the replacement of all carbon plasma facing components (PFCs) with an all metal (‘ITER-like’) wall (ILW). This has been correlated to the observed degradation of the pedestal confinement, as lower electron temperature (Te) values are routinely measured at the top of the edge barrier region. A comparative investigation of core heat transport in JET-ILW and JET-CW (carbon wall) discharges has been performed, to assess whether core confinement has also been affected by the wall change. The results presented here have been obtained by analysing a set of discharges consisting of high density JET-ILW H-mode plasmas and comparing them against their counterpart discharges in JET-CW having similar global operational parameters. The set contains 10 baseline ({βN}=1.5∼ 2 ) discharge-pairs with 2.7 T toroidal magnetic field, 2.5 MA plasma current, and 14 to 17 MW of neutral beam injection (NBI) heating. Based on a Te profile analysis using high resolution Thomson scattering (HRTS) data, the Te profile peaking (i.e. core Te (ρ = 0.3) / edge Te (ρ = 0.7)) is found to be similar, and weakly dependent on edge Te, for both JET-ILW and JET-CW discharges. When ILW discharges are seeded with N2, core and edge Te both increase to maintain a similar peaking factor. The change in core confinement is addressed with interpretative TRANSP simulations. It is found that JET-ILW H-mode plasmas have higher NBI power deposition to electrons and lower NBI power deposition to ions as compared to the JET-CW counterparts. This is an effect of the lower electron temperature at the top of the pedestal. As a result, the core electron energy confinement time is reduced in JET-ILW discharges, but the core ion energy confinement time is not decreased. Overall, the core energy confinement is found to be the same in the JET-ILW discharges compared to the JET-CW counterparts.

  9. The effects of neutral gas heating on H mode transition and maintenance currents in a 13.56 MHz planar coil inductively coupled plasma reactor

    Jayapalan, Kanesh K.; Chin, Oi-Hoong


    The H mode transition and maintenance currents in a 13.56 MHz laboratory 6 turn planar coil inductively coupled plasma (ICP) reactor are simulated for low pressure argon discharge range of 0.02-0.3 mbar with neutral gas heating and at ambient temperature. An experimentally fitted 3D power evolution plot for 0.02 mbar argon pressure is also shown to visualize the effects of hysteresis in the system. Comparisons between simulation and experimental measurements show good agreement in the pressure range of 0.02-0.3 mbar for transition currents and 0.02-0.1 mbar for maintenance currents only when neutral gas heating is considered. This suggests that neutral gas heating plays a non-negligible role in determining the mode transition points of a rf ICP system.

  10. Magnetohydrodynamic stability at the edge region in H-mode plasmas with long edge-localized-mode-free phases in the large helical device

    Toi, K.; Ohdachi, S.; Ueda, R.; Watanabe, K. Y.; Nicolas, T.; Suzuki, Y.; Ogawa, K.; Tanaka, K.; Takemura, Y.; LHD Experiment Group


    Clear suppression of magnetic fluctuations associated with resistive interchange modes (RICs) is observed during long edge-localized-mode (ELM)-free phases of the H-mode plasma in an outward-shifted configuration of the Large Helical Decice, in which a steep pressure gradient is generated at the plasma edge in the magnetic hill. The ELM-free H-phase is interrupted by large amplitude ELMs which are thought to be induced through nonlinear evolution of the RICs having m  =  1/n  =  1 dominant component (m: poloidal mode number, n: toroidal one). The m  =  1/n  =  1 RIC amplitude is enhanced about 10 times compared with the H-phase level during each ELM. In most of the H-mode shots, the final ELM-free phase returns to L-phase by a large amplitude ELM. In the L-phase, the RIC amplitude is enhanced by a factor of ~3 compared with that in the H-phase, although the edge pressure gradient is reduced considerably. Linear resistive magnetohydrodynamic stability analysis is attempted using experimentally obtained equilibrium profiles. From the numerical analysis, the distance between the location of the steepest pressure gradient and the main mode resonance surface, i.e. the rotational transform ι  =  1, is found to be important for a large growth of the m  =  1/n  =  1 RIC in the H-phase.

  11. Effect of resonant magnetic perturbations with toroidal mode numbers of 4 and 6 on edge-localized modes in single null H-mode plasmas in MAST

    Kirk, A.; Chapman, I. T.; Harrison, J.; Liu, Yueqiang; Nardon, E.; Saarelma, S.; Scannell, R.; Thornton, A. J.; the MAST Team


    The application of resonant magnetic perturbations (RMPs) with a toroidal mode number of n = 4 or n = 6 to lower single null plasmas in the MAST tokamak produces up to a factor of 5 increase in edge-localized mode (ELM) frequency and reduction in plasma energy loss associated with type-I ELMs. A threshold current for ELM mitigation is observed above which the ELM frequency increases approximately linearly with current in the coils. Despite a large scan of parameters, complete ELM suppression has not been achieved. The results have been compared with modelling performed using either the vacuum approximation or including the plasma response. During the ELM mitigated stage clear lobe structures are observed in visible-light imaging of the X-point region. The size of these lobes is correlated with the increase in ELM frequency observed. The characteristics of the mitigated ELMs are similar to those of the natural ELMs suggesting that they are type-I ELMs which are triggered at a lower pressure gradient. The application of the RMPs in the n = 4 and n = 6 configurations before the L-H transition has little effect on the power required to achieve H-mode while still allowing the first ELM to be mitigated.

  12. Experimental validation of non-uniformity effect of the radial electric field on the edge transport barrier formation in JT-60U H-mode plasmas

    Kamiya, K.; Itoh, K.; Itoh, S.-I.


    The turbulent structure formation, where strongly-inhomogeneous turbulence and global electromagnetic fields are self-organized, is a fundamental mechanism that governs the evolution of high-temperature plasmas in the universe and laboratory (e.g., the generation of edge transport barrier (ETB) of the H-mode in the toroidal plasmas). The roles of inhomogeneities of radial electric field (Er) are known inevitable. In this mechanism, whether the first derivative of Er (shear) or the second derivative of Er (curvature) works most is decisive in determining the class of nontrivial solutions (which describe the barrier structure). Here we report the experimental identification of the essential role of the Er-curvature on the ETB formation, for the first time, based on the high-spatiotemporal resolution spectroscopic measurement. We found the decisive importance of Er-curvature on ETB formation during ELM-free phase, but there is only a low correlation with the Er-shear value at the peak of normalized ion temperature gradient. Furthermore, in the ELMing phase, the effect of curvature is also quantified in terms of the relationship between pedestal width and thickness of the layer of inhomogeneous Er. This is the fundamental basis to understand the structure of transport barriers in fusion plasmas.

  13. Discovery of stationary operation of quiescent H-mode plasmas with net-zero neutral beam injection torque and high energy confinement on DIII-D

    Burrell, K. H.; Barada, K.; Chen, X.; Garofalo, A. M.; Groebner, R. J.; Muscatello, C. M.; Osborne, T. H.; Petty, C. C.; Rhodes, T. L.; Snyder, P. B.; Solomon, W. M.; Yan, Z.; Zeng, L.


    Recent experiments in DIII-D [J. L. Luxon et al., in Plasma Physics and Controlled Nuclear Fusion Research 1996 (International Atomic Energy Agency, Vienna, 1987), Vol. I, p. 159] have led to the discovery of a means of modifying edge turbulence to achieve stationary, high confinement operation without Edge Localized Mode (ELM) instabilities and with no net external torque input. Eliminating the ELM-induced heat bursts and controlling plasma stability at low rotation represent two of the great challenges for fusion energy. By exploiting edge turbulence in a novel manner, we achieved excellent tokamak performance, well above the H98y2 international tokamak energy confinement scaling (H98y2 = 1.25), thus meeting an additional confinement challenge that is usually difficult at low torque. The new regime is triggered in double null plasmas by ramping the injected torque to zero and then maintaining it there. This lowers E × B rotation shear in the plasma edge, allowing low-k, broadband, electromagnetic turbulence to increase. In the H-mode edge, a narrow transport barrier usually grows until MHD instability (a peeling ballooning mode) leads to the ELM heat burst. However, the increased turbulence reduces the pressure gradient, allowing the development of a broader and thus higher transport barrier. A 60% increase in pedestal pressure and 40% increase in energy confinement result. An increase in the E × B shearing rate inside of the edge pedestal is a key factor in the confinement increase. Strong double-null plasma shaping raises the threshold for the ELM instability, allowing the plasma to reach a transport-limited state near but below the explosive ELM stability boundary. The resulting plasmas have burning-plasma-relevant βN = 1.6-1.8 and run without the need for extra torque from 3D magnetic fields. To date, stationary conditions have been produced for 2 s or 12 energy confinement times, limited only by external hardware constraints. Stationary operation with

  14. Isotope scaling of the H mode power threshold on JET

    Righi, E.; Bartlett, D. V.; Christiansen, J. P.; Conway, G. D.; Cordey, J. G.; Eriksson, L.-G.; DeEsch, H. P. L.; Fishpool, G. M.; Gowers, C. W.; de Haas, J. C. M.; Harbour, P. J.; Hawkes, N. C.; Jacquinot, J.; Jones, T. T. C.; Kerner, W.; King, Q. A.; Lowry, C. G.; Monk, R. D.; Nielsen, P.; Rimini, F. G.; Saibene, G.; Sartori, R.; Schunke, B.; Sips, A. C. C.; Smith, R. J.; Stamp, M. F.; Start, D. F. H.; Thomsen, K.; Tubbing, B. J. D.; Zornig, N.


    Results are presented from a series of dedicated experiments carried out on JET in tritium, DT, deuterium and hydrogen plasmas to determine the dependence of the H mode power threshold on the plasma isotopic mass. The Pthr propto Aeff-1 scaling is established over the whole isotopic range. This result makes it possible for a fusion reactor with a 50:50 DT mixture to access the H mode regime with about 20% less power than that needed in a DD mixture. Results on the first systematic measurements of the power necessary for the transition of the plasma to the type I ELM regime, which occurs after the transition to H mode, are also in agreement with the Aeff-1 scaling. For a subset of discharges, measurements of Te and Ti at the top of the profile pedestal have been obtained, indicating a weak influence of the isotopic mass on the critical edge temperature thought to be necessary for the H mode transition.

  15. Effect of resonant magnetic perturbations with toroidal mode numbers of 4 and 6 on ELMs in single null H-mode plasmas in MAST

    Kirk, A; Harrison, J; Liu, Yueqiang; Nardon, E; Saarelma, S; Scannell, R; Thornton, A J


    The application of resonant magnetic perturbations (RMPs) with a toroidal mode number of n=4 or n=6 to lower single null plasmas in the MAST tokamak produces up to a factor of 5 increase in Edge Localized Mode (ELM) frequency and reduction in plasma energy loss associated with type-I ELMs. A threshold current for ELM mitigation is observed above which the ELM frequency increases approximately linearly with current in the coils. Despite a large scan of parameters, complete ELM suppression has not been achieved. The results have been compared to modelling performed using either the vacuum approximation or including the plasma response. During the ELM mitigated stage clear lobe structures are observed in visible-light imaging of the X-point region. The size of these lobes is correlated with the increase in ELM frequency observed. The characteristics of the mitigated ELMs are similar to those of the natural ELMs suggesting that they are type I ELMs which are triggered at a lower pressure gradient. The application...

  16. Inter-ELM evolution of the pedestal structures in type-I ELMy H-mode plasmas with LHW and NBI heating on EAST

    Han, X.; Zang, Q.; Xiao, S.; Wang, T.; Hu, A.; Tian, B.; Li, D.; Zhou, H.; Zhao, J.; Hsieh, C.; Li, M.; Yan, N.; Gong, X.; Hu, L.; Xu, G.; Gao, X.; the EAST Team


    The evolution characteristics of type-I ELMy high-confinement mode pedestal are examined in EAST based on the recently developed Thomson scattering system. The influence of the plasma current on pedestal evolvement has been confirmed experimentally. In the higher I p case (500 kA) the pedestal height shows an increase trend until the onset of next ELM and in the lower I p cases (300 and 400 kA), however, this buildup saturates at the first ∼30% of the ELM cycle. In contrast, the width increases only during the first ∼70% of the ELM cycle and then keeps almost stable in three I p cases, but resulting in different widening size of ∼1.5, 1 and 0.5 cm for 300, 400 and 500 kA respectively. Experimental results show that the pedestal pressure width has good correlation with poloidal beta as {{{Δ }}}{{p}{{e}},\\psi }=0.16\\sqrt{{{β }}{{p}{{o}}{{l}}}}, where the fitting coefficient 0.16 is not changed with different plasma currents but a little larger than that of other machines. For each current level, the pedestal density increases while the pedestal temperature decreases. But with increasing {I}{{p}} platforms, the pedestal height prior to the ELM onset shows a near quadratic (within error bars) increase. Experimental measurements demonstrate that the decrease of {{Δ }}{W}{{E}{{L}}{{M}}} with increasing {ν }{{p}{{e}}{{d}}}* comes mostly from the reduction of the plasma temperature drop, while the pedestal density height keeps relatively stable. Additional injection of LHW has been proved to modify the pedestal structure which should be responsible for the remaining scatter of the experimental data.

  17. The role of parallel heat transport in the relation between upstream scrape-off layer widths and target heat flux width in H-mode plasmas of NSTX.

    Ahn, J W; Boedo, J A; Maingi, R; Soukhanovskii, V A


    The physics of parallel heat transport was tested in the Scrape-off Layer (SOL) plasma of the National Spherical Torus Experiment (NSTX) [M. Ono, et al., Nucl. Fusion 40, 557 (2000) and S. M. Kaye, et al., Nucl. Fusion 45, S168 (2005)] tokamak by comparing the upstream electron temperature (T{sub e}) and density (n{sub e}) profiles measured by the mid-plane reciprocating probe to the heat flux (q{sub {perpendicular}}) profile at the divertor plate measured by an infrared (IR) camera. It is found that electron conduction explains the near SOL width data reasonably well while the far SOL, which is in the sheath limited regime, requires an ion heat flux profile broader than the electron one to be consistent with the experimental data. The measured plasma parameters indicate that the SOL energy transport should be in the conduction-limited regime for R-R{sub sep} (radial distance from the separatrix location) < 2-3 cm. The SOL energy transport should transition to the sheath-limited regime for R-R{sub sep} > 2-3cm. The T{sub e}, n{sub e}, and q{sub {perpendicular}} profiles are better described by an offset exponential function instead of a simple exponential. The conventional relation between mid plane electron temperature decay length ({lambda}{sub Te}) and target heat flux decay length ({lambda}{sub q}) is {lambda}{sub Te} = 7/2{lambda}{sub q}, whereas the newly-derived relation, assuming offset exponential functional forms, implies {lambda}{sub Te} = (2-2.5){lambda}{sub q}. The measured values of {lambda}{sub Te}/{lambda}{sub q} differ from the new prediction by 25-30%. The measured {lambda}{sub q} values in the far SOL (R-R{sub sep} > 2-3cm) are 9-10cm, while the expected values are 2.7 < {lambda}{sub q} < 4.9 cm (for sheath-limited regime). We propose that the ion heat flux profile is substantially broader than the electron heat flux profile as an explanation for this discrepancy in the far SOL.

  18. Global and pedestal confinement and pedestal structure in dimensionless collisionality scans of low-triangularity H-mode plasmas in JET-ILW

    Frassinetti, L.; Beurskens, M. N. A.; Saarelma, S.; Boom, J. E.; Delabie, E.; Flanagan, J.; Kempenaars, M.; Giroud, C.; Lomas, P.; Meneses, L.; Maggi, C. S.; Menmuir, S.; Nunes, I.; Rimini, F.; Stefanikova, E.; Urano, H.; Verdoolaege, G.; Contributors, JET


    A dimensionless collisionality scan in low-triangularity plasmas in the Joint European Torus with the ITER-like wall (JET-ILW) has been performed. The increase of the normalized energy confinement (defined as the ratio between thermal energy confinement and Bohm confinement time) with decreasing collisionality is observed. Moreover, at low collisionality, a confinement factor H98, comparable to JET-C, is achieved. At high collisionality, the low normalized confinement is related to a degraded pedestal stability and a reduction in the density-profile peaking. The increase of normalized energy confinement is due to both an increase in the pedestal and in the core regions. The improvement in the pedestal is related to the increase of the stability. The improvement in the core is driven by (i) the core temperature increase via the temperature-profile stiffness and by (ii) the density-peaking increase driven by the low collisionality. Pedestal stability analysis performed with the ELITE (edge-localized instabilities in tokamak equilibria) code has a reasonable qualitative agreement with the experimental results. An improvement of the pedestal stability with decreasing collisionality is observed. The improvement is ascribed to the reduction of the pedestal width, the increase of the bootstrap current and the reduction of the relative shift between the positions of the pedestal density and pedestal temperature. The EPED1 model predictions for the pedestal pressure height are qualitatively well correlated with the experimental results. Quantitatively, EPED1 overestimates the experimental pressure by 15-35%. In terms of the pedestal width, a correct agreement (within 10-15%) between the EPED1 and the experimental width is found at low collisionality. The experimental pedestal width increases with collisionality. Nonetheless, an extrapolation to low-collisionality values suggests that the width predictions from the KBM constraint are reasonable for ITER.

  19. Investigation of lower hybrid current drive during H-mode in EAST tokamak

    Li Miao-Hui; Liu Fu-Kun; Wang Mao; Xu Han-Dong; Wan Bao-Nian; Ding Bo-Jiang; Kong Er-Hua; Zhang Lei; Zhang Xin-Jun; Qian Jin-Ping; Yan Ning; Han Xiao-Feng; Shan Jia-Fang


    H-mode discharges with lower hybrid current drive (LHCD) alone are achieved in EAST divertor plasma over a wide parameter range.These H-mode discharges are characterized by a sudden drop in Dα emission and a spontaneous rise in main plasma density.Good lower hybrid (LH) coupling during H-mode is obtained by putting the plasma close to the antenna and by injecting D2 gas from a pipe near the grill mouse.The analysis of lower hybrid current drive properties shows that the LH deposition profile shifts off axis during H-mode,and current drive (CD) efficiency decreases due to the increase in density.Modeling results of H-mode discharges with a general ray tracing code GENRAY are reported.

  20. Application of divertor cryopumping to H-mode density control in DIII-D

    Mahdavi, M.A.; Ferron, J.R.; Hyatt, A.W. [and others


    In this paper we describe the method and the results of experiments where a unique in-vessel cryopump-baffle system was used to control density of H-mode plasmas. We were able to independently regulate current and density of ELMing H-mode plasmas, each over a range of factor two, and measure the H-mode confinement scaling with plasma density and current. With a modest pumping speed of {approx}40 kl/s, particle exhaust rates as high as 2 {times} 10{sup 22} atom/s{sup {minus}1} have been observed.

  1. Progress In Understanding The Enhanced Petestal H-mode In NSTX

    Gerhardt, S. P.; Canik, J. M.; Maingi, R.; Battaglia, D.; Bell, R. E.; Guttenfelder, W.; LeBlanc, B. P.; Smith, D. R.; Yuh, H.; Sabbagh, S.


    ThIS paper describes the enhanced pedestal (EP) H-mode observed in the National Spherical Torus Experiment (NSTX). The defining characteristics of EP H-mode are given, namely i)transition after the L- to H-mode transition, ii) region of very steep ion temperature gradient, and iii) associated region of strong rotational shear. A newly observed long-pulse EP H-mode example shows quiescent behavior for as long as the heating and current drive sources are maintained. Cases are shown where the region of steep ion temperature gradient is located at the very edge, and cases where it is shifted up to 10 cm inward from the plasma edge; these cases are united by a common dependence of the ion temperature gradient on the toroidal rotation frequency shear. EP H-mode examples have been observed across a wide range of q95 and pedestal collisionality. No strong changes in the fluctuation amplitudes have been observed following the eP H-mode transition, and transport analysis indicates that the ion t hermal transport is comparable to or less than anticipated from a simple neoclassical transport model. Cases are shown where EP H-modes were reliably generated, through these low-q95 examples were difficult to sustain. A case where an externally triggered ELM precipitates the transition to EP H-mode is also shown, though an initial experiment designed to trigger EP-H-modes in this fashion was successful.

  2. Statistical study of TCV disruptivity and H-mode accessibility

    Martin, Y.; Deschenaux, C.; Lister, J.B.; Pochelon, A. [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP)


    Optimising tokamak operation consists of finding a path, in a multidimensional parameter space, which leads to the desired plasma characteristics and avoids hazards regions. Typically the desirable regions are the domain where an L-mode to H-mode transition can occur, and then, in the H-mode, where ELMs and the required high density

  3. PREFACE: 31st European Physical Society Conference on Plasma Physics

    Dendy, Richard


    This special issue of Plasma Physics and Controlled Fusion comprises refereed papers contributed by invited speakers at the 31st European Physical Society Conference on Plasma Physics. The conference was jointly hosted by the Rutherford Appleton Laboratory, by the EURATOM/UKAEA Fusion Association and by Imperial College London, where it took place from 28 June to 2 July 2004. The overall agenda for this conference was set by the Board of the Plasma Physics Division of the European Physical Society, chaired by Friedrich Wagner (MPIPP, Garching) and his successor Jo Lister (CRPP, Lausanne). It built on developments in recent years, by further increasing the scientific diversity of the conference programme, whilst maintaining its depth and quality. A correspondingly diverse Programme Committee was set up, whose members are listed below. The final task of the Programme Committee has been the preparation of this special issue. In carrying out this work, as in preparing the scientific programme of the conference, the Programme Committee formed specialist subcommittees representing the different fields of plasma science. The chairmen of these subcommittees, in particular, accepted a very heavy workload on behalf of their respective research communities. It is a great pleasure to take this opportunity to thank: Emilia R Solano (CIEMAT, Madrid), magnetic confinement fusion; Jürgen Meyer-ter-Vehn (MPQ, Garching), laser-plasma interaction and beam plasma physics; and Jean-Luc Dorier (CRPP, Lausanne), dusty plasmas. The relatively few papers in astrophysical and basic plasma physics were co-ordinated by a small subcommittee which I led. Together with Peter Norreys (RAL, Chilton), we five constitute the editorial team for this special issue. The extensive refereeing load, compressed into a short time interval, was borne by the Programme Committee members and by many other experts, to whom this special issue owes much. We are also grateful to the Local Organizing Committee

  4. Divertor Heat Flux Mitigation in High-Performance H-mode Discharges in the National Spherical Torus Experiment.

    Soukhanovskii, V A; Maingi, R; Gates, D; Menard, J


    Experiments conducted in high-performance 1.0 MA and 1.2 MA 6 MW NBI-heated H-mode discharges with a high magnetic flux expansion radiative divertor in NSTX demonstrate that significant divertor peak heat flux reduction and access to detachment may be facilitated naturally in a highly-shaped spherical torus (ST) configuration. Improved plasma performance with high {beta}{sub t} = 15-25%, a high bootstrap current fraction f{sub BS} = 45-50%, longer plasma pulses, and an H-mode regime with smaller ELMs has been achieved in the strongly-shaped lower single null configuration with elongation {kappa} = 2.2-2.4 and triangularity {delta} = 0.6-0.8. Divertor peak heat fluxes were reduced from 6-12 MW/m{sup 2} to 0.5-2 MW/m{sup 2} in ELMy H-mode discharges using the inherently high magnetic flux expansion f{sub m} = 16-25 and the partial detachment of the outer strike point at several D{sub 2} injection rates. A good core confinement and pedestal characteristics were maintained, while the core carbon concentration and the associated Z{sub eff} were reduced. The partially detached divertor regime was characterized by an increase in divertor radiated power, a reduction of ion flux to the plate, and a large neutral compression ratio. Spectroscopic measurements indicated a formation of a high-density, low temperature region adjacent to the outer strike point, where substantial increases in the volume recombination rate and CII, CIII emission rates was measured.

  5. ECE-imaging of the H-mode pedestal (invited)

    Tobias, B. J.; Nazikian, R. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Austin, M. E. [University of Texas-Austin, Austin, Texas 78712 (United States); Boom, J. E.; Classen, I. G. J. [Dutch Institute for Fundamental Energy Research, 3430 BE Nieuwegein (Netherlands); Burrell, K. H.; Snyder, P. B. [General Atomics, P.O.Box 85608, San Diego, California 92186 (United States); Domier, C. W.; Luhmann, N. C. Jr. [University of California-Davis, Davis, California 95616 (United States)


    A synthetic diagnostic has been developed that reproduces the highly structured electron cyclotron emission (ECE) spectrum radiated from the edge region of H-mode discharges. The modeled dependence on local perturbations of the equilibrium plasma pressure allows for interpretation of ECE data for diagnosis of local quantities. Forward modeling of the diagnostic response in this region allows for improved mapping of the observed fluctuations to flux surfaces within the plasma, allowing for the poloidal mode number of coherent structures to be resolved. In addition, other spectral features that are dependent on both T{sub e} and n{sub e} contain information about pedestal structure and the electron energy distribution of localized phenomena, such as edge filaments arising during edge-localized mode (ELM) activity.

  6. Integrated scenario with type-III ELMy H-mode edge: extrapolation to ITER

    Rapp, J.; Corre, Y.; Andrew, Y.; M.R. de Baar,; Beurskens, M.; Brezinsek, S.; Brix, M.; Devaux, S.; Eich, T.; Felton, R.; Fundamenski, W.; Giroud, C.; Howell, D.; Huber, A.; Jachmich, S.; Joffrin, E.; Korotkov, A.; Matthews, G. F.; McDonald, D. C.; Meigs, A.; Monier-Garbet, P.; Morgan, P.; Nunes, I.; van Rooij, G. J.; Sauter, O.; Stamp, M. F.; Telesca, G.; de Vries, P. C.; Zagorski, R.


    One of the most severe problems for fusion reactors is the power load on the plasma facing components. The challenge is to develop operation scenarios, which combine sufficient energy confinement with benign heat loads to the plasma facing components. The radiative type-III ELMy H-mode seems a possi

  7. Effort of lower hybrid current drive experiments toward to H-mode in EAST

    Ding, B. J.; Li, M. H.; Liu, F. K.; Shan, J. F.; Li, Y. C.; Wang, M.; Liu, L.; Zhao, L. M.; Yang, Y.; Wu, Z. G.; Feng, J. Q.; Hu, H. C.; Jia, H.; Cheng, M.; Zang, Q.; Lyu, B.; Duan, Y. M.; Lin, S. Y.; Wu, J. H.; Hillairet, J.; Ekedahl, A.; Peysson, Y.; Goniche, M.; Tuccillo, A. A.; Cesario, R.; Amicucci, L.; Shen, B.; Gong, X. Z.; Xu, G. S.; Zhao, H. L.; Hu, L. Q.; Li, J. G.; Wan, B. N.; EAST Team


    Lower hybrid current drive (LHCD) is an effective tool to achieve high confinement (H-mode) plasma in EAST. To utilize LHCD for accessing H-mode plasma, efforts have been made to improve LHW (lower hybrid wave)-plasma coupling and current drive capability at high density. Improved LHW-plasma coupling by means of local gas puffing and gas puffing from the electron side is routinely used during EAST operation with LHCD. High density experiments suggest that low recycling and high LH frequency are preferred for LHCD experiments at high density, consistent with previous results in other machines. The effect of LHCD on the current profile in EAST demonstrates that it is possible to control the plasma profile by optimizing the LHW spectrum. Repeatable H-mode plasma was obtained by LHCD and the maximum density during H-mode with the combination of 2.45 GHz and 4.6 GHz LH waves was up to 4.5  ×  1019 m-3.

  8. Predictions of H-mode performance in ITER

    Budny, R. V.; Andre, R.; Bateman, G.; Halpern, F.; Kessel, C. E.; Kritz, A.; McCune, D.


    Time-dependent integrated predictive modeling is carried out using the PTRANSP code to predict fusion power and parameters such as alpha particle density and pressure in ITER H-mode plasmas. Auxiliary heating by negative ion neutral beam injection and ion cyclotron heating of He3 minority ions are modeled, and the GLF23 transport model is used in the prediction of the evolution of plasma temperature profiles. Effects of beam steering, beam torque, plasma rotation, beam current drive, pedestal temperatures, sawtooth oscillations, magnetic diffusion, and accumulation of He ash are treated self-consistently. Variations in assumptions associated with physics uncertainties for standard base-line DT H-mode plasmas (with Ip=15 MA, BTF=5.3 T, and Greenwald fraction=0.86) lead to a range of predictions for DT fusion power PDT and quasi-steady state fusion QDT (≡ PDT/Paux). Typical predictions assuming Paux = 50-53 MW yield PDT = 250- 720 MW and QDT = 5 - 14. In some cases where Paux is ramped down or shut off after initial flat-top conditions, quasi-steady QDT can be considerably higher, even infinite. Adverse physics assumptions such as existence of an inward pinch of the helium ash and an ash recycling coefficient approaching unity lead to very low values for PDT. Alternative scenarios with different heating and reduced performance regimes are also considered including plasmas with only H or D isotopes, DT plasmas with toroidal field reduced 10 or 20%, and discharges with reduced beam voltage. In full-performance D-only discharges, tritium burn-up is predicted to generate central tritium densities up to 1016/m3 and DT neutron rates up to 5×1016/s, compared with the DD neutron rates of 6×1017/s. Predictions with the toroidal field reduced 10 or 20% below the planned 5.3 T and keeping the same q98, Greenwald fraction, and Βη indicate that the fusion yield PDT and QDT will be lower by about a factor of two (scaling as B3.5).

  9. Ubiquity of non-diffusive momentum transport in JET H-modes

    Weisen, H.; Camenen, Y.; Salmi, A.; Versloot, T. W.; de Vries, P. C.; Maslov, M.; Tala, T.; Beurskens, M.; Giroud, C.; JET-EFDA Contributors,


    A broad survey of the experimental database of neutral beam heated baseline H-modes and hybrid scenarios in the JET tokamak has established the ubiquity of non-diffusive momentum transport mechanisms in rotating plasmas. As a result of their presence, the normalized angular frequency gradient R &

  10. Energy deposition onto HL-2A divertor plates in ELMy H-mode discharges using infrared thermography

    Gao, J.M., E-mail:; Li, W.; Liu, Y.; Ji, X.Q.; Cheng, J.; Dong, Y.B.; Chen, C.Y.; Feng, B.B.; Lu, J.; Yi, P.; Yang, Q.W.


    Using infrared (IR) thermography, power loads onto the divertor plates have been investigated in ELMy H-mode plasmas on HL-2A. In the ELMy H-mode discharges, ELMs are the largest contributors to the divertor target energy load. Analysis of energy balance shows that up to 45% of the energy losses are deposited onto the divertor targets during ELMs and about 30% are found as plasma radiation. Moreover, divertor heat flux mitigation has been achieved during an ELMy H-mode phase by using Supersonic Molecular Beam Injection (SMBI), characterized by a sharp increase of ELM frequency and a reduction in peak heat flux. The increased plasma radiation energy losses, especially the doubled plasma radiation in the divertor region, should be responsible for the reduction of integrated energy deposition onto divertor targets.

  11. The H-mode power threshold in JET

    Start, D.F.H.; Bhatnagar, V.P.; Campbell, D.J.; Cordey, J.G.; Esch, H.P.L. de; Gormezano, C.; Hawkes, N.; Horton, L.; Jones, T.T.C.; Lomas, P.J.; Lowry, C.; Righi, E.; Rimini, F.G.; Saibene, G.; Sartori, R.; Sips, G.; Stork, D.; Thomas, P.; Thomsen, K.; Tubbing, B.J.D.; Von Hellermann, M.; Ward, D.J. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking


    New H-mode threshold data over a range of toroidal field and density values have been obtained from the present campaign. The scaling with n{sub e} B{sub t} is almost identical with that of the 91/92 period for the same discharge conditions. The scaling with toroidal field alone gives somewhat higher thresholds than the older data. The 1991/2 database shows a scaling of P{sub th} (power threshold) with n{sub e} B{sub t} which is approximately linear and agrees well with that observed on other tokamaks. For NBI and carbon target tiles the threshold power is a factor of two higher with the ion {Nu}B drift away from the target compared with the value found with the drift towards the target. The combination of ICRH and beryllium tiles appears to be beneficial for reducing P{sub th}. The power threshold is largely insensitive to plasma current, X-point height and distance between the last closed flux surface and the limiter, at least for values greater than 2 cm. (authors). 3 refs., 6 figs.

  12. Scaling studies of the H-mode pedestal

    Groebner, R.J.; Osborne, T.H.


    The structure and scaling of the H-mode pedestal are examined for discharges in the DIII-D tokamak. For typical conditions, the pedestal values of the ion and electron temperatures T{sub i} and T{sub e} are comparable. Measurements of main ion and C{sup 6+} profiles indicate that the ion pressure gradient in the barrier is 50%--100% of the electron pressure gradient for deuterium plasmas. The magnitude of the pressure gradient in the barrier often exceeds the predictions of infinite-n ballooning mode theory by a factor of two. Moreover, via the bootstrap current, the finite pressure gradient acts to entirely remove ballooning stability limits for typical discharges. For a large dataset, the width of the pressure barrier {delta} is best described by the dimensionless scaling {delta}/R {proportional_to} ({beta}{sub pol}{sup ped}){sup 0.4} where ({beta}{sub pol}{sup ped}) is the pedestal value of poloidal beta and R is the major radius. Scalings based on the poloidal ion gyroradius or the edge density gradient do not adequately describe overall trends in the data set and the propagation of the pressure barrier observed between edge-localized modes. The width of the T{sub i} barrier is quite variable and is not a good measure of the width of the pressure barrier.

  13. Modelling of edge plasma transport during H-mode of EAST by SOLPS5.0%东方超环托卡马克高约束模式边界等离子体输运数值模拟研究

    杜海龙; 桑超峰; 王亮; 孙继忠; 刘少承; 汪惠乾; 张凌; 郭后扬; 王德真


    This work aims at modeling the ELMing H-mode of the experimental advanced superconducting Tokamak (EAST) using edge plasma code package SOLPS5.0. The steady-state H-mode is obtained by adjusting the perpendicular radial anomalous transport coefficient according to the given upstream profiles of experimental measurements (shot 36291). The downstream divertor region can be then modeled once the simulated upstream electron density and temperature agrees well with the experimental measurements. On the basis of the H-mode simulation, the effect of the drift on divertor targets power asymmetry and that of the power damping width of scrape-off layer (SOL) on the peak power density to the divertor target are modeled, the simulation results indicate that the drift (E × B, B ×∇B) is one of the main reasons for targets power asymmetry, and the increasing of power damping width of the SOL will reduce the peak power load on the divertor target sharply;besides, due to the presence of interaction between plasma and neutral gas or radiation in divertor region, the effect of the power damping width on the divertor target power load is decreased.%利用SOLPS5.0模拟研究东方超环托卡马克(EAST)高约束模式时的刮削层等离子体.在高约束模式放电实验参数(第36291炮)的限制下,通过调整上游区径向反常输运系数来实现高约束模式模拟,在上游电子密度和温度与实验符合的条件下能够很好地进行下游区模拟.在实现高约束模拟的基础上又分别研究了漂移项对偏滤器靶板能流不对称性的影响和上游能流衰减宽度对靶板能流密度峰值的影响.通过模拟发现,漂移是导致EAST放电内外靶板不对称性的主要原因,增大上游能流衰减宽度可以明显降低入射到靶板的峰值热流,并且偏滤器区辐射以及与中性粒子的相互作用减小了能流的衰减宽度对达到靶板能流的影响.

  14. Plasma calprotectin predicts mortality in patients with ST segment elevation myocardial infarction treated with primary percutaneous coronary intervention

    Jensen, Louise J N; Haahr-Pedersen, Sune Ammentorp; Bjerre, Mette


    We investigated the predictive value of plasma calprotectin levels for mortality in patients with ST segment elevation myocardial infarction (STEMI) successfully treated with primary percutaneous coronary intervention (pPCI).......We investigated the predictive value of plasma calprotectin levels for mortality in patients with ST segment elevation myocardial infarction (STEMI) successfully treated with primary percutaneous coronary intervention (pPCI)....

  15. PREFACE: 11th IAEA Technical Meeting on H-mode Physics and Transport Barriers

    Takizuka, Tomonori


    This volume of Journal of Physics: Conference Series contains papers based on invited talks and contributed posters presented at the 11th IAEA Technical Meeting on H-mode Physics and Transport Barriers. This meeting was held at the Tsukuba International Congress Center in Tsukuba, Japan, on 26-28 September 2007, and was organized jointly by the Japan Atomic Energy Agency and the University of Tsukuba. The previous ten meetings in this series were held in San Diego (USA) 1987, Gut Ising (Germany) 1989, Abingdon (UK) 1991, Naka (Japan) 1993, Princeton (USA) 1995, Kloster Seeon (Germany) 1997, Oxford (UK) 1999, Toki (Japan) 2001, San Diego (USA) 2003, and St Petersburg (Russia) 2005. The purpose of the eleventh meeting was to present and discuss new results on H-mode (edge transport barrier, ETB) and internal transport barrier, ITB, experiments, theory and modeling in magnetic fusion research. It was expected that contributions give new and improved insights into the physics mechanisms behind high confinement modes of H-mode and ITBs. Ultimately, this research should lead to improved projections for ITER. As has been the tradition at the recent meetings of this series, the program was subdivided into six topics. The topics selected for the eleventh meeting were: H-mode transition and the pedestal-width Dynamics in ETB: ELM threshold, non-linear evolution and suppression, etc Transport relations of various quantities including turbulence in plasmas with ITB: rotation physics is especially highlighted Transport barriers in non-axisymmetric magnetic fields Theory and simulation on transport barriers Projections of transport barrier physics to ITER For each topic there was an invited talk presenting an overview of the topic, based on contributions to the meeting and on recently published external results. The six invited talks were: A Leonard (GA, USA): Progress in characterization of the H-mode pedestal and L-H transition N Oyama (JAEA, Japan): Progress and issues in

  16. Analysis of the H-mode density limit in the ASDEX upgrade tokamak using bolometry

    Bernert, Matthias


    The high confinement mode (H-mode) is the operational scenario foreseen for ITER, DEMO and future fusion power plants. At high densities, which are favourable in order to maximize the fusion power, a back transition from the H-mode to the low confinement mode (L-mode) is observed. This H-mode density limit (HDL) occurs at densities on the order of, but below, the Greenwald density. In this thesis, the HDL is revisited in the fully tungsten walled ASDEX Upgrade tokamak (AUG). In AUG discharges, four distinct operational phases were identified in the approach towards the HDL. First, there is a stable H-mode, where the plasma density increases at steady confinement, followed by a degrading H-mode, where the core electron density is fixed and the confinement, expressed as the energy confinement time, reduces. In the third phase, the breakdown of the H-mode and transition to the L-mode, the overall electron density is fixed and the confinement decreases further, leading, finally, to an L-mode, where the density increases again at a steady confinement at typical L-mode values until the disruptive Greenwald limit is reached. These four phases are reproducible, quasi-stable plasma regimes and provide a framework in which the HDL can be further analysed. Radiation losses and several other mechanisms, that were proposed as explanations for the HDL, are ruled out for the current set of AUG experiments with tungsten walls. In addition, a threshold of the radial electric field or of the power flux into the divertor appears to be responsible for the final transition back to L-mode, however, it does not determine the onset of the HDL. The observation of the four phases is explained by the combination of two mechanisms: a fueling limit due to an outward shift of the ionization profile and an additional energy loss channel, which decreases the confinement. The latter is most likely created by an increased radial convective transport at the edge of the plasma. It is shown that the

  17. Study on H-mode access at low density with lower hybrid current drive and lithium-wall coatings on the EAST superconducting tokamak

    Xu, G.S.; Wan, B.N.; Li, J.G.


    The first high-confinement mode (H-mode) with type-III edge localized modes at an H factor of HIPB98(y,2) ~ 1 has been obtained with about 1 MW lower hybrid wave power on the EAST superconducting tokamak. The first H-mode plasma appeared after wall conditioning by lithium (Li) evaporation before ...

  18. The role of MHD instabilities in the improved H-mode scenario

    Flaws, Asher


    Recently a regime of tokamak operation has been discovered, dubbed the improved H-mode scenario, which simultaneously achieves increased energy confinement and stability with respect to standard H-mode discharges. It has been suggested that magnetohydrodynamic (MHD) instabilities play some role in establishing this regime. In this thesis MHD instabilities were identified, characterised, and catalogued into a database of improved H-mode discharges in order to statistically examine their behaviour. The onset conditions of MHD instabilities were compared to existing models based on previous H-mode studies. Slight differences were found, most notably a reduced {beta}{sub N} onset threshold for the frequently interrupted regime for neoclassical tearing modes (NTM). This reduced threshold is due to the relatively low magnetic shear of the improved H-mode regime. This study also provided a first-time estimate for the seed island size of spontaneous onset NTMs, a phenomenon characteristic of the improved H-mode scenario. Energy confinement investigations found that, although the NTM impact on confinement follows the same model applicable to other operating regimes, the improved H-mode regime acts to mitigate the impact of NTMs by limiting the saturated island sizes for NTMs with toroidal mode number n {>=} 2. Surprisingly, although a significant loss in energy confinement is observed during the sawtooth envelope, it has been found that discharges containing fishbones and low frequency sawteeth achieve higher energy confinement than those without. This suggests that fishbone and sawtooth reconnection may indeed play a role in establishing the high confinement regime. It was found that the time evolution of the central magnetic shear consistently locks in the presence of sawtooth and fishbone reconnection. Presumably this is due to the periodic redistribution of the central plasma current, an effect which is believed to help establish and maintain the characteristic current

  19. VH mode accessibility and global H-mode properties in previous and present JET configurations

    Jones, T.T.C.; Ali-Arshad, S.; Bures, M.; Christiansen, J.P.; Esch, H.P.L. de; Fishpool, G.; Jarvis, O.N.; Koenig, R.; Lawson, K.D.; Lomas, P.J.; Marcus, F.B.; Sartori, R.; Schunke, B.; Smeulders, P.; Stork, D.; Taroni, A.; Thomas, P.R.; Thomsen, K. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking


    In JET VH modes, there is a distinct confinement transition following the cessation of ELMs, observed in a wide variety of tokamak operating conditions, using both NBI and ICRF heating methods. Important factors which influence VH mode accessibility such as magnetic configuration and vessel conditions have been identified. The new JET pumped divertor configuration has much improved plasma shaping control and power and particle exhaust capability and should permit exploitation of plasmas with VH confinement properties over an even wider range of operating regimes, particularly at high plasma current; first H-modes have been obtained in the 1994 JET operating period and initial results are reported. (authors). 7 refs., 6 figs.

  20. Anomalous transport in the H-mode pedestal of Alcator C-Mod discharges

    Pankin, A. Y.; Hughes, J. W.; Greenwald, M. J.; Kritz, A. H.; Rafiq, T.


    Anomalous transport in the H-mode pedestal region of five Alcator C-Mod discharges, representing a collisionality scan is analyzed. The understanding of anomalous transport in the pedestal region is important for the development of a comprehensive model for the H-mode pedestal slope. In this research, a possible role of the drift resistive inertial ballooning modes (Rafiq et al 2010 Phys. Plasmas 17 082511) in the edge of Alcator C-Mod discharges is analyzed. The stability analysis, carried out using the TRANSP code, indicates that the DRIBM modes are strongly unstable in Alcator C-Mod discharges with large electron collisionality. An improved interpretive analysis of H-mode pedestal experimental data is carried out utilizing the additive flux minimization technique (Pankin et al 2013 Phys. Plasmas 20 102501) together with the guiding-center neoclassical kinetic XGC0 code. The neoclassical and neutral physics are simulated in the XGC0 code and the anomalous fluxes are computed using the additive flux minimization technique. The anomalous fluxes are reconstructed and compared with each other for the collisionality scan Alcator C-Mod discharges. It is found that the electron thermal anomalous diffusivities at the pedestal top increase with the electron collisionality. This dependence can also point to the drift resistive inertial ballooning modes as the modes that drive the anomalous transport in the plasma edge of highly collisional discharges.

  1. Realization of minute-long steady-state H-mode discharges on EAST

    Xianzu, GONG; Baonian, WAN; Jiangang, LI; Jinping, QIAN; Erzhong, LI; Fukun, LIU; Yanping, ZHAO; Mao, WANG; Handong, XU; A, M. GAROFALO; Annika, EKEDAH; Siye, DING; Juan, HUANG; Ling, ZHANG; Qing, ZANG; Haiqing, LIU; Long, ZENG; Shiyao, LIN; Biao, SHEN; Bin, ZHANG; Linming, SHAO; Bingjia, XIAO; Jiansheng, HU; Chundong, HU; Liqun, HU; Liang, WANG; Youwen, SUN; Guosheng, XU; Yunfeng, LIANG; Nong, XIANG; EAST Team


    In the 2016 EAST experimental campaign, a steady-state long-pulse H-mode discharge with an ITER-like tungsten divertor lasting longer than one minute has been obtained using only RF heating and current drive, through an integrated control of the wall conditioning, plasma configuration, divertor heat flux, particle exhaust, impurity management, and effective coupling of multiple RF heating and current drive sources at high injected power. The plasma current (I p ∼ 0.45 MA) was fully-noninductively driven (V loop technology studies on EAST, and will benefit the physics basis for steady state operation of ITER and CFETR.

  2. Plasma high-mobility group box 1 levels predict mortality after ST-segment elevation myocardial infarction

    Sørensen, Morten V; Pedersen, Sune; Møgelvang, Rasmus


    We evaluated the potential association between plasma high-mobility group box 1 (HMGB1) levels and outcome in patients with ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention.......We evaluated the potential association between plasma high-mobility group box 1 (HMGB1) levels and outcome in patients with ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention....

  3. Analysis of fuelling requirements in ITER H-modes with SOLPS-EPED1 derived scalings

    Polevoi, A. R.; Loarte, A.; Kukushkin, A. S.; Pacher, H. D.; Pacher, G. W.; Köchl, F.


    Fuelling requirements for ITER are analysed in relation to pellet fuelling and ELM pacing, and a divertor power load control consistent with the ITER pumping and fuel throughput capabilities. The plasma parameters at the separatrix and the particle sources are derived from scalings based on SOLPS simulations. Effective transport coefficients in the H-mode pedestal are derived from EPED1 + SOLPS scalings for the pedestal height and width. 1.5D transport is simulated in the ASTRA framework. The operating window for ITER DT plasmas with the required fusion performance and level of ELM, and divertor power load control compatible with ITER fuelling and pumping capabilities, is determined. It is shown that the flexibility of the ITER fuelling systems, comprising pellet and gas injection systems, enables operation with Q  =  10, which was found to be marginal in previous studies following a similar approach but with different assumptions. The present assessment shows that a reduction of by a factor ~2 (from 9 to 5  ×  1019 m-3) in 15 MA H-mode plasmas leads to a reduction in the required pellet fuelling rate by a factor of four. Results of the analysis of the fuelling requirements for a range of ITER scenarios are found to be similar to those obtained with the JINTRAC code that included 2D modelling of the edge plasma.

  4. Comparison of hybrid and baseline ELMy H-mode confinement in JET with the carbon wall

    Beurskens, M. N. A.; Frassinetti, L.; Challis, C.; Osborne, T.; Snyder, P. B.; Alper, B.; Angioni, C.; Bourdelle, C.; Buratti, P.; Crisanti, F.; Giovannozzi, E.; Giroud, C.; Groebner, R.; Hobirk, J.; Jenkins, I.; Joffrin, E.; Leyland, M. J.; Lomas, P.; Mantica, P.; McDonald, D.; Nunes, I.; Rimini, F.; Saarelma, S.; Voitsekhovitch, I.; de Vries, P.; Zarzoso, D.; Contributors, JET-EFDA


    The confinement in JET baseline type I ELMy H-mode plasmas is compared to that in so-called hybrid H-modes in a database study of 112 plasmas in JET with the carbon fibre composite (CFC) wall. The baseline plasmas typically have βN ˜ 1.5-2, H98 ˜ 1, whereas the hybrid plasmas have βN ˜ 2.5-3, H98 contains both low- (δ ˜ 0.2-0.25) and high-triangularity (δ ˜ 0.4) hybrid and baseline H-mode plasmas from the last JET operational campaigns in the CFC wall from the period 2008-2009. Based on a detailed confinement study of the global as well as the pedestal and core confinement, there is no evidence that the hybrid and baseline plasmas form separate confinement groups; it emerges that the transition between the two scenarios is of a gradual kind rather than demonstrating a bifurcation in the confinement. The elevated confinement enhancement factor H98 in the hybrid plasmas may possibly be explained by the density dependence in the τ98 scaling as n0.41 and the fact that the hybrid plasmas operate at low plasma density compared to the baseline ELMy H-mode plasmas. A separate regression on the confinement data in this study shows a reduction in the density dependence as n0.09±0.08. Furthermore, inclusion of the plasma toroidal rotation in the confinement regression provides a scaling with the toroidal Alfvén Mach number as Mach_A^{0.41+/- 0.07} and again a reduced density dependence as n0.15±0.08. The differences in pedestal confinement can be explained on the basis of linear MHD stability through a coupling of the total and pedestal poloidal pressure and the pedestal performance can be improved through plasma shaping as well as high β operation. This has been confirmed in a comparison with the EPED1 predictive pedestal code which shows a good agreement between the predicted and measured pedestal pressure within 20-30% for a wide range of βN ˜ 1.5-3.5. The core profiles show a strong degree of pressure profile consistency. No beneficial effect of core

  5. H-mode fueling optimization with the supersonic deuterium jet in NSTX

    Soukhanovskii, V A; Bell, M G; Bell, R E; Gates, D A; Kaita, R; Kugel, H W; LeBlanc, B P; Lundberg, D P; Maingi, R; Menard, J E; Raman, R; Roquemore, A L; Stotler, D P


    High-performance, long-pulse 0.7-1.2 MA 6-7 MW NBI-heated small-ELM H-mode plasma discharges are developed in the National Spherical Torus Experiment (NSTX) as prototypes for confinement and current drive extrapolations to future spherical tori. It is envisioned that innovative lithium coating techniques for H-mode density pumping and a supersonic deuterium jet for plasma refueling will be used to achieve the low pedestal collisionality and low n{sub e}/n{sub G} fractions (0.3-0.6), both of which being essential conditions for maximizing the non-inductive (bootstrap and beam driven) current fractions. The low field side supersonic gas injector (SGI) on NSTX consists of a small converging-diverging graphite Laval nozzle and a piezoelectric gas valve. The nozzle is capable of producing a deuterium jet with Mach number M {le} 4, estimated gas density at the nozzle exit n {le} 5 x 10{sup 23} m{sup -3}, estimated temperature T {ge} 70 K, and flow velocity v = 2:4 km/s. The nozzle Reynolds number Reis {approx_equal} 6000. The nozzle and the valve are enclosed in a protective carbon fiber composite shroud and mounted on a movable probe at a midplane port location. Despite the beneficial L-mode fueling experience with supersonic jets in limiter tokamaks, there is a limited experience with fueling of high-performance H-mode divertor discharges and the associated density, MHD stability, and MARFE limits. In initial supersonic deuterium jet fueling experiments in NSTX, a reliable H-mode access, a low NBI power threshold, P{sub LH} {le} 2 MW, and a high fueling efficiency (0.1-0.4) have been demonstrated. Progress has also been made toward a better control of the injected fueling gas by decreasing the uncontrolled high field side (HFS) injector fueling rate by up to 95 % and complementing it with the supersonic jet fueling. These results motivated recent upgrades to the SGI gas delivery and control systems. The new SGI-Upgrade (SGI-U) capabilities include multi-pulse ms

  6. H-mode pedestal and threshold studies over an expanded operating space on Alcator C-Moda)

    Hubbard, A. E.; Hughes, J. W.; Bespamyatnov, I. O.; Biewer, T.; Cziegler, I.; LaBombard, B.; Lin, Y.; McDermott, R.; Rice, J. E.; Rowan, W. L.; Snipes, J. A.; Terry, J. L.; Wolfe, S. M.; Wukitch, S.


    This paper reports on studies of the edge transport barrier and transition threshold of the high confinement (H) mode of operation on the Alcator C-Mod tokamak [I. H. Hutchinson et al., Phys. Plasmas 1, 1511 (1994)], over a wide range of toroidal field (2.6-7.86T) and plasma current (0.4-1.7MA). The H-mode power threshold and edge temperature at the transition increase with field. Barrier widths, pressure limits, and confinement are nearly independent of field at constant current, but the operational space at high B shifts toward higher temperature and lower density and collisionality. Experiments with reversed field and current show that scrape-off-layer flows in the high-field side depend primarily on configuration. In configurations with the B ×∇B drift away from the active X-point, these flows lead to more countercurrent core rotation, which apparently contributes to higher H-mode thresholds. In the unfavorable case, edge temperature thresholds are higher, and slow evolution of profiles indicates a reduction in thermal transport prior to the transition in particle confinement. Pedestal temperatures in this case are also higher than in the favorable configuration. Both high-field and reversed-field results suggest that parameters at the L-H transition are influencing the evolution and parameters of the H-mode pedestal.

  7. EDGE2D-EIRENE modelling of near SOL E r: possible impact on the H-mode power threshold

    Chankin, A. V.; Delabie, E.; Corrigan, G.; Harting, D.; Maggi, C. F.; Meyer, H.; Contributors, JET


    Recent EDGE2D-EIRENE simulations of JET plasmas showed a significant difference between radial electric field (E r) profiles across the separatrix in two divertor configurations, with the outer strike point on the horizontal target (HT) and vertical target (VT) (Chankin et al 2016 Nucl. Mater. Energy, doi: 10.1016/j.nme.2016.10.004). Under conditions (input power, plasma density) where the HT plasma went into the H-mode, a large positive E r spike in the near scrape-off layer (SOL) was seen in the code output, leading to a very large E × B shear across the separatrix over a narrow region of a fraction of a cm width. No such E r feature was obtained in the code solution for the VT configuration, where the H-mode power threshold was found to be twice as high as in the HT configuration. It was hypothesised that the large E × B shear across the separatrix in the HT configuration could be responsible for the turbulence suppression leading to an earlier (at lower input power) L-H transition compared to the VT configuration. In the present work these ideas are extended to cover some other experimental observations on the H-mode power threshold variation with parameters which typically are not included in the multi-machine H-mode power threshold scalings, namely: ion mass dependence (isotope H-D-T exchange), dependence on the ion ∇B drift direction, and dependence on the wall material composition (ITER-like wall versus carbon wall in JET). In all these cases EDGE2D-EIRENE modelling shows larger positive E r spikes in the near SOL under conditions where the H-mode power threshold is lower, at least in the HT configuration.

  8. Role of density gradient driven trapped electron mode turbulence in the H-mode inner core with electron heating

    Ernst, D. R.; Burrell, K. H.; Guttenfelder, W.; Rhodes, T. L.; Dimits, A. M.; Bravenec, R.; Grierson, B. A.; Holland, C.; Lohr, J.; Marinoni, A.; McKee, G. R.; Petty, C. C.; Rost, J. C.; Schmitz, L.; Wang, G.; Zemedkun, S.; Zeng, L.


    A series of DIII-D [J. L. Luxon, Nucl. Fusion 42, 614 (2002)] low torque quiescent H-mode experiments show that density gradient driven trapped electron mode (DGTEM) turbulence dominates the inner core of H-mode plasmas during strong electron cyclotron heating (ECH). Adding 3.4 MW ECH doubles Te/Ti from 0.5 to 1.0, which halves the linear DGTEM critical density gradient, locally reducing density peaking, while transport in all channels displays extreme stiffness in the density gradient. This suggests that fusion α-heating may degrade inner core confinement in H-mode plasmas with moderate density peaking and low collisionality, with equal electron and ion temperatures, key conditions expected in burning plasmas. Gyrokinetic simulations using GYRO [J. Candy and R. E. Waltz, J. Comput. Phys. 186, 545 (2003)] (and GENE [Jenko et al., Phys. Plasmas 7, 1904 (2000)]) closely match not only particle, energy, and momentum fluxes but also density fluctuation spectra from Doppler backscattering (DBS), with and without ECH. Inner core DBS density fluctuations display discrete frequencies with adjacent toroidal mode numbers, which we identify as DGTEMs. GS2 [Dorland et al., Phys. Rev. Lett. 85, 5579 (2000)] predictions show the DGTEM can be suppressed, to avoid degradation with electron heating, by broadening the current density profile to attain q0>qmin>1 .

  9. Advancing the Physics Basis of Quiescent H-mode through Exploration of ITER Relevant Parameters

    Solomon, W. M. [PPPL; Burrell, K. H. [General Atomics; Fenstermacher, M. E. [LLNL; Garofalo, A. M. [General Atomics; Grierson, B. A. [PPPL; Loarte, A. [ITER; McKee, G. R. [U of Wisc, Madison; Nazikian, R. [PPPL; Snyder, B. P. [General Atomics


    Recent experiments on DIII-D have overcome a long-standing limitation in accessing quiescent H-mode (QH-mode), a high confinement state of the plasma that does not exhibit the explosive instabilities associated with edge localized modes (ELMs). In the past, QH-mode was associated with low density operation, but has now been extended to high normalized densities compatible with operation envisioned for ITER. Through the use of strong shaping, QH-mode plasmas have been maintained at high densities, both absolute (ηe ≈ 7 × 1019 m—3) and normalized Greenwald fraction (ηe/ηG > 0:7) . In these plasmas, the pedestal can evolve to very high pressures and current as the density is increased. Calculations of the pedestal height and width from the EPED model are quantitatively consistent with the experimental observed evolution with density. The comparison of the dependence of the maximum density threshold for QH-mode with plasma shape help validate the underlying theoretical peeling-ballooning models describing ELM stability. High density QH-mode operation with strong shaping has allowed stable access to a previously predicted regime of very high pedestal dubbed \\Super H-mode". In general, QH-mode is found to achieve ELM-stable operation while maintaining adequate impurity exhaust, due to the enhanced impurity transport from an edge harmonic oscillation, thought to be a saturated kink- peeling mode driven by rotation shear. In addition, the impurity confinement time is not affected by rotation, even though the energy confinement time and measured E Χ B shear is observed to increase at low toroidal rotation. Together with demonstrations of high beta, high confinement and low q95 for many energy confinement times, these results suggest QH-mode as a potentially attractive operating scenario for ITER's Q=10 mission.

  10. H-Mode Accelerating Structures with PMQ Beam Focusing

    Kurennoy, Sergey S; O'Hara, James F; Olivas, Eric R; Wangler, Thomas P


    We have developed high-efficiency normal-conducting RF accelerating structures by combining H-mode resonator cavities and a transverse beam focusing by permanent-magnet quadrupoles (PMQ), for beam velocities in the range of a few percent of the speed of light. The shunt impedance of inter-digital H-mode (IH-PMQ) structures is 10-20 times higher than that of a conventional drift-tube linac, while the transverse size is 4-5 times smaller. Results of the combined 3-D modeling - electromagnetic computations, multi-particle beam-dynamics simulations with high currents, and thermal-stress analysis - for an IH-PMQ accelerator tank are presented. The accelerating field profile in the tank is tuned to provide the best propagation of a 50-mA deuteron beam using coupled iterations of electromagnetic and beam-dynamics modeling. Measurements of a cold model of the IH-PMQ tank show a good agreement with the calculations. H-PMQ accelerating structures following a short RFQ can be used both in the front end of ion linacs or ...

  11. Role of a MHD mode crash in triggering H-mode at marginal heating power on the HL-2A tokamak

    Cheng, J.; Xu, Y.; Hidalgo, C.; Yan, L. W.; Liu, Yi; Jiang, M.; Li, Y. G.; Yu, L. M.; Dong, Y. B.; Li, D.; Liu, L.; Zhong, W. L.; Xu, J. Q.; Huang, Z. H.; Ji, X. Q.; Song, S. D.; Yu, D. L.; Xu, M.; Shi, Z. B.; Pan, O.; Yang, Q. W.; Ding, X. T.; Duan, X. R.; Liu, Yong


    The impact of a low frequency MHD mode crash on triggering the H-mode has been studied in detail on the HL-2A tokamak. The mode manifests fishbone characteristics with a precession frequency f ≈ 14- 19 kHz. The abrupt mode crash evokes substantial energy release from the core to the plasma boundary and hence increases the edge pressure gradient and Er × B flow shear, which further suppresses turbulence and leads to confinement improvement into the H-mode. Under the same NBI heating (∼1 MW), the I-phase plasma transits into H-mode with a rapid MHD mode crash while it returns to the L-mode without the presence of the mode in the I-phase. With increasing heating power by the ECRH added to the NBI, the MHD mode disappears. The statistical result shows that with the MHD mode crash the heating power for accessing the H-mode is significantly lower than that without the mode crash. All these facts reveal that the MHD mode crash in the I-phase plays a critical role in trigging the I → H transition at marginal heating power. In addition, it has been found that with the same NBI power heating, the magnitude of the mode (crash) increases with increasing plasma density, implying larger energy release being needed to access the H-mode for higher density plasmas.

  12. Fuel ion rotation measurement and its implications on H-mode theories

    Kim, J.; Burrell, K.H.; Gohil, P.; Groebner, R.J.; Hinton, F.L.; Kim, Y.B.; Seraydarian, R. [General Atomics, San Diego, CA (United States); Mandl, W. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany). Oberflaechenphysik; Wade, M.R. [Oak Ridge National Lab., TN (United States)


    Poloidal and toroidal rotation of the fuel ions (He{sup 2+}) and the impurity ions (C{sup 6+} and B{sup 5+}) in H-mode helium plasmas have been investigated in the DIII-D tokamak by means of charge exchange recombination spectroscopy, resulting in the discovery that the fuel ion poloidal rotation is in the ion diamagnetic drift direction while the impurity ion rotation is in the electron diamagnetic drift direction. The radial electric field obtained from radial force balance analysis of the measured pressure gradients and rotation velocities is shown to be the same regardless of which ion species is used and therefore is a more fundamental parameter than the rotation flows in studying H-mode phenomena. It is shown that the three contributions to the radial electric field (diamagnetic, poloidal rotation, and toroidal rotation terms) are comparable and consequently the poloidal flow does not solely represent the E {times} B flow. In the high-shear edge region, the density scale length is comparable to the ion poloidal gyroradius, and thus neoclassical theory is not valid there. In view of this new discovery that the fuel and impurity ions rotate in opposite sense, L-H transition theories based on the poloidal rotation may require improvement.

  13. The 13th International Workshop on H-mode Physics and Transport Barriers (Oxford, UK, 2011) The 13th International Workshop on H-mode Physics and Transport Barriers (Oxford, UK, 2011)

    Saibene, G.


    The 13th International Workshop on H-mode Physics and Transport Barriers, held in Lady Margaret Hall College in Oxford in October 2011 continues the tradition of bi-annual international meetings dedicated to the study of transport barriers in fusion plasmas. The first meeting of this series took place in S Diego (CA, US) in 1987, and since then scientists in the fusion community studying the formation and effects of transport barriers in plasmas have been meeting at this small workshop to discuss progress, new experimental evidence and related theoretical studies. The first workshops were strongly focussed on the characterization and understanding of the H-mode plasma, discovered in ASDEX in 1982. Tokamaks throughout the entire world were able to reproduce the H-mode transition in the following few years and since then the H-mode has been recognised as a pervasive physics feature of toroidally confined plasmas. Increased physics understanding of the H-mode transition and of the properties of H-mode plasmas, together with extensive development of diagnostic capabilities for the plasma edge, led to the development of edge transport barrier studies and theory. The H-mode Workshop reflected this extension in interest, with more and more contributions discussing the phenomenology of edge transport barriers and instabilities (ELMs), L-H transition and edge transport barrier formation theory. In the last 15 years, in response to the development of fusion plasma studies, the scientific scope of the workshop has been broadened to include experimental and theoretical studies of both edge and internal transport barriers, including formation and sustainment of transport barriers for different transport channels (energy, particle and momentum). The 13th H-mode Workshop was organized around six leading topics, and, as customary for this workshop, a lead speaker was selected for each topic to present to the audience the state-of-the-art, new understanding and open issues, as well

  14. Fusion power production in International Thermonuclear Experimental Reactor baseline H-mode scenarios

    Rafiq, T.; Kritz, A. H. [Department of Physics, Lehigh University, Bethlehem, Pennsylvania 18015 (United States); Kessel, C. E. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08540 (United States); Pankin, A. Y. [Tech-X Corporation, Boulder, Colorado 80303 (United States)


    Self-consistent simulations of 15 MA ITER H-mode DT scenarios, from ramp-up through flat-top, are carried out. Electron and ion temperatures, toroidal angular frequency, and currents are evolved, in simulations carried out using the predictive TRANSPort and integrated modeling code starting with initial profiles and equilibria obtained from tokamak simulation code studies. Studies are carried out examining the dependence and sensitivity of fusion power production on electron density, argon impurity concentration, choice of radio frequency heating, pedestal temperature without and with E × B flow shear effects included, and the degree of plasma rotation. The goal of these whole-device ITER simulations is to identify dependencies that might impact ITER fusion performance.

  15. Chaotic motions of the L-mode to H-mode transition model in tokamak

    Fang-qi CHEN; Liang-qiang ZHOU; Xia WANG; Yu-shu CHEN


    The chaotic dynamics of the transport equation for the L-mode to H-mode near the plasma in a tokamak is studied in detail with the Melnikov method.The transport equations represent a system with external and parametric excitation.The critical curves separating the chaotic regions and nonchaotic regions are presented for the system with periodically external excitation and linear parametric excitation,or cubic parametric excitation,respectively.The results obtained here show that there exist uncontrollable regions in which chaos always take place via heteroclinic bifurcation for the system with linear or cubic parametric excitation.Especially,there exists a controllable frequency,excited at which chaos does not occur via homoclinic bifurcation no matter how large the excitation amplitude is for the system with cubic parametric excitation.Some complicated dynamical behaviors are obtained for this class of systems.

  16. Heuristic Drift-based Model of the Power Scrape-off width in H-mode Tokamaks

    Robert J. Goldston


    An heuristic model for the plasma scrape-off width in H-mode plasmas is introduced. Grad B and curv B drifts into the SOL are balanced against sonic parallel flows out of the SOL, to the divertor plates. The overall particle flow pattern posited is a modification for open field lines of Pfirsch-Shlüter flows to include sinks to the divertors. These assumptions result in an estimated SOL width of ~ 2aρp/R. They also result in a first-principles calculation of the particle confinement time of H-mode plasmas, qualitatively consistent with experimental observations. It is next assumed that anomalous perpendicular electron thermal diffusivity is the dominant source of heat flux across the separatrix, investing the SOL width, defined above, with heat from the main plasma. The separatrix temperature is calculated based on a two-point model balancing power input to the SOL with Spitzer-Härm parallel thermal conduction losses to the divertor. This results in a heuristic closed-form prediction for the power scrape-off width that is in reasonable quantitative agreement both in absolute magnitude and in scaling with recent experimental data from deuterium plasmas. Further work should include full numerical calculations, including all magnetic and electric drifts, as well as more thorough comparison with experimental data.

  17. An Heuristic Drift-Based Model of the Power Scrape-Off Width in H-Mode Tokamaks

    Robert J. Goldston


    An heuristic model for the plasma scrape-off width in H-mode plasmas is introduced. Grad B and curv B drifts into the SOL are balanced against sonic parallel flows out of the SOL, to the divertor plates. The overall mass flow pattern posited is a modification for open field lines of Pfirsch-Shlüter flows to include sinks to the divertors. These assumptions result in an estimated SOL width of 2aρp/R. They also result in a first-principles calculation of the particle confinement time of H-mode plasmas, qualitatively consistent with experimental observations. It is next assumed that anomalous perpendicular electron thermal diffusivity is the dominant source of heat flux across the separatrix, investing the SOL width, defined above, with heat from the main plasma. The separatrix temperature is calculated based on a two-point model balancing power input to the SOL with Spitzer-Härm parallel thermal conduction losses to the divertor. This results in an heuristic closed-form prediction for the power scrape-off width that is in remarkable quantitative agreement both in absolute magnitude and in scaling with recent experimental data. Further work should include full numerical calculations, including all magnetic and electric drifts, as well as more thorough comparison with experimental data.

  18. One-dimensional modelling of limit-cycle oscillation and H-mode power scaling

    Wu, Xingquan; Xu, Guosheng; Wan, Baonian; Rasmussen, Jens Juul; Naulin, Volker; Nielsen, Anders Henry


    To understand the connection between the dynamics of microscopic turbulence and the macroscale power scaling in the L-I-H transition in magnetically confined plasmas, a new time-dependent, one-dimensional (in radius) model has been developed. The model investigates the radial force balance equation at the edge region of the plasma and applies the quenching effect of turbulence via the E × B flow shear rate exceeding the shear suppression threshold. By slightly ramping up the heating power, the spatio-temporal evolution of turbulence intensity, density and pressure profiles, poloidal flow and E × B flow self-consistently displays the L-H transition with an intermediate phase (I-phase) characterized by limit-cycle oscillations. Since the poloidal flow is partially damped to the neoclassical flow in the edge region, the numerical results reveal two different oscillation relationships between the E × B flow and the turbulence intensity depending on which oscillation of the diamagnetic flow or poloidal flow is dominant. Specifically, by including the effects of boundary conditions of density and temperature, the model results in a linear dependence of the H-mode access power on the density and magnetic field. These results imply that the microscopic turbulence dynamics and the macroscale power scaling for the L-H transition are strongly connected.

  19. Effect of Aspect Ratio on H-mode and ELM Characteristics

    Thome, K. E.; Bodner, G. M.; Bongard, M. W.; Burke, M. G.; Fonck, R. J.; Kriete, D. M.


    The H-mode confinement regime is achieved at near-unity aspect ratio (A PLH , behaves quite differently at low- A when compared with high- A operations. PLH /PLH_ITPA 08 increases sharply as A is lowered and no difference in PLH for limited and diverted plasmas is observed at A ~ 1 . 2 . No minimum in PLH with density is observed. Some of these results are consistent with the FM3 model for the L-H transition. Two classes of ELMs have been observed. Small, Type III-like ELMs are present at low input power and have n >PLH , they transition to large, Type-I-like ELMs with intermediate 5 < n < 15 . The Type III ELM magnetic structures behave opposite that of high- A plasmas, with n much higher, presumably due to the naturally higher J / B peeling mode drive at low- A . Long-sought measurements of the Jedge (R , t) pedestal collapse during an ELM event show a complex, multimodal pedestal collapse and the subsequent ejection of a current-carrying filament. Work supported by US DOE grant DE-FG02-96ER54375.

  20. The prognostic value of plasma soluble ST2 in hospitalized Chinese patients with heart failure.

    Rongcheng Zhang

    Full Text Available BACKGROUND: sST2 has been shown to be a risk predictor in heart failure (HF. Our aim was to explore the characteristics and prognostic value of soluble ST2 (sST2 in hospitalized Chinese patients with HF. METHODS AND RESULTS: We consecutively enrolled 1528 hospitalized patients with HF. Receiver operating characteristic (ROC and multivariable Cox proportional hazards analysis were used to assess the prognostic values of sST2. Adverse events were defined as all-cause death and cardiac transplantation. During a median follow-up of 19.1 months, 325 patients experienced adverse events. Compared with patients free of events, sST2 concentrations were significantly higher in patients with events (P55.6 ng/mL independently predicted events in comparison to the lowest quartile (≤25.2 ng/mL when adjusted by multivariable model. In ROC analysis, the area under the curve for sST2 was not different from that for NT-proBNP in short and longer term. Over time, sST2 also improved discrimination and reclassification of risk beyond NT-proBNP. CONCLUSIONS: sST2 is a strong independent risk predictor in Chinese patients hospitalized with HF and can significantly provide additional prognostic value to NT-proBNP in risk prediction.

  1. Can we use plasma hyperosmolality as a predictor of mortality for ST-segment elevation myocardial infarction?

    Tatlisu, Mustafa A; Kaya, Adnan; Keskin, Muhammed; Uzman, Osman; Borklu, Edibe B; Cinier, Goksel; Hayiroglu, Mert I; Tatlisu, Kiymet; Eren, Mehmet


    The aim of this study was to investigate the association of plasma osmolality with all-cause mortality in ST-segment elevation myocardial infarction (STEMI) patients treated with a primary percutaneous coronary intervention. This study included 3748 patients (mean age 58.3±11.8 years, men 81%) with STEMI treated with primary percutaneous coronary intervention. The following formula was used to measure the plasma osmolality at admission: osmolality=1.86×sodium (mmol/l)+glucose (mg/dl)/18+BUN (mg/dl)/2.8+9. The patients were followed up for a mean period of 22±10 months. Patients with higher plasma osmolality had 3.7 times higher in-hospital (95% confidence interval: 2.7-5.1) and 3.2 times higher long-term (95% confidence interval: 2.5-4.1) all-cause mortality rates than patients with lower plasma osmolality. Plasma osmolality was found to be a predictor of both in-hospital and long-term all-cause mortality. Hence, plasma osmolality can be used to detect high-risk patients in STEMI.

  2. Papers presented at the IAEA technical committee meeting on H-mode physics

    TCV team [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP)


    The two papers contained in this report deal with ohmic H-modes and effect on confinement of edge localized modes in the TCV tokamak. They were presented by the TCV team at the 1995 IAEA technical committee meeting on H-mode physics. figs., tabs., refs.

  3. Prognostic Value of Plasma Intermedin Level in Patients With Non-ST-Segment Elevation Acute Coronary Syndrome.

    Li, Pengyang; Shi, Lin; Han, Yalei; Zhao, Yuntao; Qi, Yongfen; Wang, Bin


    Intermedin (IMD), an autocrine/paracrine biologically active peptide, plays a critical role in maintaining vascular homeostasis. Recent research has shown that high plasma levels of IMD are associated with poor outcomes for patients with ST-segment elevation acute myocardial infarction. However, the prognostic utility of IMD levels in non-ST-segment elevation acute coronary syndrome (NSTE-ACS) has not yet been investigated. We hypothesized that the level of plasma IMD would have prognostic value in patients with NSTE-ACS. Plasma IMD was determined by radioimmunoassay in 132 NSTE-ACS patients on admission to hospital and 132 sex- and age-matched healthy-control subjects. Major adverse cardiovascular events (MACEs), including death, heart failure, hospitalization, and acute myocardial infarction, were noted during follow-up. In total, 23 patients suffered MACEs during the follow-up period (mean 227 ± 118 days, range 2-421 days). Median IMD levels were higher in NSTE-ACS patients than control [320.0 (250.9/384.6) vs. 227.2 (179.7/286.9) pg/mL, P variables and NT-proBNP showed that the risk of MACEs increased by a factor of 12.96 (95% CI, 3.26-49.42; P <0.001) with high IMD levels (at the cut-off value). IMD has potential as a prognostic biomarker for predicting MACEs in patients with NSTE-ACS.

  4. Measurement of deuterium density profiles in the H-mode steep gradient region using charge exchange recombination spectroscopy on DIII-D

    Haskey, S. R.; Grierson, B. A.; Burrell, K. H.; Chrystal, C.; Groebner, R. J.; Kaplan, D. H.; Pablant, N. A.; Stagner, L.


    Recent completion of a thirty two channel main-ion (deuterium) charge exchange recombination spectroscopy (CER) diagnostic on the DIII-D tokamak [J. L. Luxon, Nucl. Fusion 42, 614 (2002)] enables detailed comparisons between impurity and main-ion temperature, density, and toroidal rotation. In a H-mode DIII-D discharge, these new measurement capabilities are used to provide the deuterium density profile, demonstrate the importance of profile alignment between Thomson scattering and CER diagnostics, and aid in determining the electron temperature at the separatrix. Sixteen sightlines cover the core of the plasma and another sixteen are densely packed towards the plasma edge, providing high resolution measurements across the pedestal and steep gradient region in H-mode plasmas. Extracting useful physical quantities such as deuterium density is challenging due to multiple photoemission processes. These challenges are overcome using a detailed fitting model and by forward modeling the photoemission using the FIDASIM code, which implements a comprehensive collisional radiative model.

  5. Role of Density Gradient Driven Trapped Electron Modes in the H-Mode Inner Core with Electron Heating

    Ernst, D.


    We present new experiments and nonlinear gyrokinetic simulations showing that density gradient driven TEM (DGTEM) turbulence dominates the inner core of H-Mode plasmas during strong electron heating. Thus α-heating may degrade inner core confinement in H-Mode plasmas with moderate density peaking. These DIII-D low torque quiescent H-mode experiments were designed to study DGTEM turbulence. Gyrokinetic simulations using GYRO (and GENE) closely match not only particle, energy, and momentum fluxes, but also density fluctuation spectra, with and without ECH. Adding 3.4 MW ECH doubles Te /Ti from 0.5 to 1.0, which halves the linear TEM critical density gradient, locally flattening the density profile. Density fluctuations from Doppler backscattering (DBS) intensify near ρ = 0.3 during ECH, displaying a band of coherent fluctuations with adjacent toroidal mode numbers. GYRO closely reproduces the DBS spectrum and its change in shape and intensity with ECH, identifying these as coherent TEMs. Prior to ECH, parallel flow shear lowers the effective nonlinear DGTEM critical density gradient 50%, but is negligible during ECH, when transport displays extreme stiffness in the density gradient. GS2 predictions show the DGTEM can be suppressed, to avoid degradation with electron heating, by broadening the current density profile to attain q0 >qmin > 1 . A related experiment in the same regime varied the electron temperature gradient in the outer half-radius (ρ ~ 0 . 65) using ECH, revealing spatially coherent 2D mode structures in the Te fluctuations measured by ECE imaging. Fourier analysis with modulated ECH finds a threshold in Te profile stiffness. Supported by the US DOE under DE-FC02-08ER54966 and DE-FC02-04ER54698.

  6. Development of long pulse RF heating and current drive for H-mode scenarios with metallic walls in WEST

    Ekedahl, Annika, E-mail:; Bourdelle, Clarisse; Artaud, Jean-François; Bernard, Jean-Michel; Bufferand, Hugo; Colas, Laurent; Decker, Joan; Delpech, Léna; Dumont, Rémi; Goniche, Marc; Helou, Walid; Hillairet, Julien; Lombard, Gilles; Magne, Roland; Mollard, Patrick; Nardon, Eric; Peysson, Yves; Tsitrone, Emmanuelle [CEA, IRFM, F-13108 Saint Paul-lez-Durance (France)


    The longstanding expertise of the Tore Supra team in long pulse heating and current drive with radiofrequency (RF) systems will now be exploited in the WEST device (tungsten-W Environment in Steady-state Tokamak) [1]. WEST will allow an integrated long pulse tokamak programme for testing W-divertor components at ITER-relevant heat flux (10-20 MW/m{sup 2}), while treating crucial aspects for ITER-operation, such as avoidance of W-accumulation in long discharges, monitoring and control of heat fluxes on the metallic plasma facing components (PFCs) and coupling of RF waves in H-mode plasmas. Scenario modelling using the METIS-code shows that ITER-relevant heat fluxes are compatible with the sustainment of long pulse H-mode discharges, at high power (up to 15 MW / 30 s at I{sub P} = 0.8 MA) or high fluence (up to 10 MW / 1000 s at I{sub P} = 0.6 MA) [2], all based on RF heating and current drive using Ion Cyclotron Resonance Heating (ICRH) and Lower Hybrid Current Drive (LHCD). This paper gives a description of the ICRH and LHCD systems in WEST, together with the modelling of the power deposition of the RF waves in the WEST-scenarios.

  7. Thermo-mechanical and damage analyses of EAST carbon divertor under type-I ELMy H-mode operation

    Li, W.X. [School of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230026 (China); Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Song, Y.T. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); School of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230026 (China); Ye, M.Y. [School of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230026 (China); Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Peng, X.B., E-mail: [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Wu, S.T. [School of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230026 (China); Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Qian, X.Y.; Zhu, C.C. [School of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230026 (China)


    Highlights: • Type-I ELMy H-mode is one of the most severe operating environment in tokamak. • An actual time-history heat load has been used in thermo-mechanical analysis. • The analysis results are time-dependent during the whole discharge process. • The analysis could be very useful in evaluating the operational capability of the divertor. - Abstract: The lower carbon divertor has been used since 2008 in EAST, and many significant physical results, like the 410 s long pulse discharge and the 32 s H-mode operation, have been achieved. As the carbon divertor will still be used in the next few years while the injected auxiliary heating power would be increased gradually, it’s necessary to evaluate the operational capability of the carbon divertor under the heat loads during future operation. In this paper, an actual time-history heat load during type-I ELMy H-mode from EAST experiment, as one of the most severe operating environment in tokamak, has been used in the calculation and analysis. The finite element (FE) thermal and mechanical calculations have been carried out to analysis the stress and deformation of the carbon divertor during the heat loads. According to the results, the main impact on the overall temperature comes from the relative stable phase before and after the type-I ELMs and local peak load, and the transient thermal load such as type-I ELMy only has a significant effect on the surface temperature of the graphite tiles. The carbon divertor would work with high stress near the screw bolts in the current operational conditions, because of high preload and conservative frictional coefficient between the bolts and heatsink. For the future operation, new plasma facing materials (PFM) and divertor technology should be developed.

  8. Flux amplification and sustainment of ST plasmas by multi-pulsed coaxial helicity injection on HIST

    Higashi, T.; Ishihara, M.; Kikuchi, Y.; Fukumoto, N.; Nagata, M.


    The Helicity Injected Spherical Torus (HIST) device has been developed towards high-current start up and sustainment by Multi-pulsed Coaxial Helicity Injection (M-CHI) method. Multiple pulses operation of the coaxial plasma gun can build the magnetic field of STs and spheromak plasmas in a stepwise manner. So far, successive gun pulses on SSPX at LLNL were demonstrated to maintain the magnetic field of spheromak in a quasi-steady state against resistive decay [1]. The resistive 3D-MHD numerical simulation [2] for STs reproduced the current amplification by the M-CHI method and confirmed that stochastic magnetic field was reduced during the decay phase. By double pulsed operation on HIST, the plasma current was effectively amplified against the resistive decay. The life time increases up to 10 ms which is longer than that in the single CHI case (4 ms). The edge poloidal fields last between 0.5 ms and 6 ms like a repetitive manner. During the second driven phase, the toroidal ion flow is driven in the same direction as the plasma current as well as in the initial driven phase. At the meeting, we will discuss a current amplification mechanism based on the merging process with the plasmoid injected secondly from the gun. [1] B. Hudson et al., Phys. Plasmas Vol.15, 056112 (2008). [2] Y. Kagei et al., J. Plasma Fusion Res. Vol.79, 217 (2003).

  9. Plasma properties from the multi-wavelength analysis of the November 1st 2003 CME/shock event

    Benna, Carlo; Giordano, Silvio; Gioannini, Lorenzo


    The analysis of the spectral properties and dynamic evolution of a CME/shock event observed on November 1st 2003 in white-light by the LASCO coronagraph and in the ultraviolet by the UVCS instrument operating aboard SOHO, has been performed to compute the properties of some important plasma parameters in the middle corona below about 2 solar radii. Simultaneous observations obtained with the MLSO/Mk4 white-light coronagraph, providing both the early evolution of the CME expansion in the corona and the pre-shock electron density profile along the CME front, were also used to study this event. By combining the above information with the analysis of the metric type II radio emission detected by ground-based radio spectrographs, we finally derive estimates of the values of the local Alfv\\'en speed and magnetic field strength in the solar corona.

  10. High resolution main-ion charge exchange spectroscopy in the DIII-D H-mode pedestal

    Grierson, B. A.; Burrell, K. H.; Chrystal, C.; Groebner, R. J.; Haskey, S. R.; Kaplan, D. H.


    A new high spatial resolution main-ion (deuterium) charge-exchange spectroscopy system covering the tokamak boundary region has been installed on the DIII-D tokamak. Sixteen new edge main-ion charge-exchange recombination sightlines have been combined with nineteen impurity sightlines in a tangentially viewing geometry on the DIII-D midplane with an interleaving design that achieves 8 mm inter-channel radial resolution for detailed profiles of main-ion temperature, velocity, charge-exchange emission, and neutral beam emission. At the plasma boundary, we find a strong enhancement of the main-ion toroidal velocity that exceeds the impurity velocity by a factor of two. The unique combination of experimentally measured main-ion and impurity profiles provides a powerful quasi-neutrality constraint for reconstruction of tokamak H-mode pedestals.

  11. Pregnancy associated plasma protein A, a potential marker for vulnerable plaque in patients with non-ST-segment elevation acute coronary syndrome

    Iversen, Kasper; Teisner, Ane S; Teisner, Borge


    OBJECTIVES: To describe the presence and time-related pattern of circulating pregnancy associated plasma protein A (PAPP-A) levels in patients with non ST-segment elevation acute coronary syndrome (NSTE-ACS). DESIGN AND METHODS: Consecutively admitted patients (N=573) with clinical signs of NSTE-...

  12. Dependence of the L- to H-mode Power Threshold on Toroidal Rotation and the Link to Edge Turbulence Dynamics

    McKee, G; Gohil, P; Schlossberg, D; Boedo, J; Burrell, K; deGrassie, J; Groebner, R; Makowski, M; Moyer, R; Petty, C; Rhodes, T; Schmitz, L; Shafer, M; Solomon, W; Umansky, M; Wang, G; White, A; Xu, X


    The injected power required to induce a transition from L-mode to H-mode plasmas is found to depend strongly on the injected neutral beam torque and consequent plasma toroidal rotation. Edge turbulence and flows, measured near the outboard midplane of the plasma (0.85 < r/a < 1.0) on DIII-D with the high-sensitivity 2D beam emission spectroscopy (BES) system, likewise vary with rotation and suggest a causative connection. The L-H power threshold in plasmas with the ion {del}B drift away from the X-point decreases from 4-6 MW with co-current beam injection, to 2-3 MW with near zero net injected torque, and to <2 MW with counter injection. Plasmas with the ion {del}B drift towards the X-point exhibit a qualitatively similar though less pronounced power threshold dependence on rotation. 2D edge turbulence measurements with BES show an increasing poloidal flow shear as the L-H transition is approached in all conditions. At low rotation, the poloidal flow of turbulent eddies near the edge reverses prior to the L-H transition, generating a significant poloidal flow shear that exceeds the measured turbulence decorrelation rate. This increased poloidal turbulence velocity shear may facilitate the L-H transition. No such reversal is observed in high rotation plasmas. The poloidal turbulence velocity spectrum exhibits a transition from a Geodesic Acoustic Mode zonal flow to a higher-power, lower frequency, zero-mean-frequency zonal flow as rotation varies from co-current to balanced during a torque scan at constant injected neutral beam power, perhaps also facilitating the L-H transition. This reduced power threshold at lower toroidal rotation may benefit inherently low-rotation plasmas such as ITER.

  13. Edge Recycling and Heat Fluxes in L- and H-mode NSTX Plasmas

    V.A. Soukhanovskii; R. Maingi; R. Raman; H. Kugel; B. LeBlanc; A.L. Roquemore; C.J. Lasnier; the NSTX Research Team


    Introduction Edge characterization experiments have been conducted in NSTX to provide an initial survey of the edge particle and heat fluxes and their scaling with input power and electron density. The experiments also provided a database of conditions for the analyses of the NSTX global particle sources, core fueling, and divertor operating regimes.

  14. Gyrokinetic studies of core turbulence features in ASDEX Upgrade H-mode plasmas

    Navarro, A. Bañón, E-mail:; Told, D. [Max-Planck-Institut für Plasmaphysik, Boltzmannstrase 2, 85748 Garching (Germany); Department of Physics and Astronomy, University of California, Los Angeles, California 90095 (United States); Happel, T.; Görler, T.; Abiteboul, J.; Bustos, A.; Doerk, H. [Max-Planck-Institut für Plasmaphysik, Boltzmannstrase 2, 85748 Garching (Germany); Jenko, F. [Max-Planck-Institut für Plasmaphysik, Boltzmannstrase 2, 85748 Garching (Germany); Department of Physics and Astronomy, University of California, Los Angeles, California 90095 (United States); Max-Planck/Princeton Center for Plasma Physics (United States)


    Gyrokinetic validation studies are crucial for developing confidence in the model incorporated in numerical simulations and thus improving their predictive capabilities. As one step in this direction, we simulate an ASDEX Upgrade discharge with the GENE code, and analyze various fluctuating quantities and compare them to experimental measurements. The approach taken is the following. First, linear simulations are performed in order to determine the turbulence regime. Second, the heat fluxes in nonlinear simulations are matched to experimental fluxes by varying the logarithmic ion temperature gradient within the expected experimental error bars. Finally, the dependence of various quantities with respect to the ion temperature gradient is analyzed in detail. It is found that density and temperature fluctuations can vary significantly with small changes in this parameter, thus making comparisons with experiments very sensitive to uncertainties in the experimental profiles. However, cross-phases are more robust, indicating that they are better observables for comparisons between gyrokinetic simulations and experimental measurements.

  15. In-out divertor flow asymmetries during ELMs in ASDEX Upgrade H-mode plasmas

    Tsalas, M. [NCSR ' Demokritos' , Institute of Nuclear Technology - Radiation Protection, 153 10 Aghia Paraskevi, Attica (Greece) and EDFA-JET CSU, Abingdon OX14 3DB, Oxon (United Kingdom)]. E-mail:; Coster, D. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Garching (Germany); Fuchs, C. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Garching (Germany); Herrmann, A. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Garching (Germany); Kallenbach, A. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Garching (Germany); Mueller, H.W. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Garching (Germany); Neuhauser, J. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Garching (Germany); Rohde, V. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Garching (Germany); Tsois, N. [NCSR ' Demokritos' , Institute of Nuclear Technology - Radiation Protection, 153 10 Aghia Paraskevi, Attica (Greece)


    In ASDEX Upgrade, a fast reciprocating probe positioned in the lower divertor, capable of accessing the low-field side (LFS) and high-field side (HFS) scrape-off layer (SOL) just below the x-point, as well as the private flux region, was equipped with a Mach head and used to investigate fast flow fluctuations and in-out divertor flow asymmetries during ELMs. We compare the flow behaviour during ELMs in the three separate regions. Flow enhancement is observed in the HFS SOL, with Mach number values reaching or exceeding M = 2, flow reversal in the LFS SOL, and complex fluctuating behaviour in the private flux region (which includes flow reversal). We discuss the possible mechanisms that could drive these observations.

  16. Particle and power deposition on divertor targets in EAST H-mode plasmas

    Wang, L.; Xu, G.S.; Guo, H.Y.


    The effects of edge-localized modes (ELMs) on divertor particle and heat fluxes were investigated for the first time in the Experimental Advanced Superconducting Tokamak (EAST). The experiments were carried out with both double null and lower single null divertor configurations, and comparisons w...

  17. Compatibility of separatrix density scaling for divertor detachment with H-mode pedestal operation in DIII-D

    Leonard, A. W.; McLean, A. G.; Makowski, M. A.; Stangeby, P. C.


    The midplane separatrix density is characterized in response to variations in upstream parallel heat flux density and central density through deuterium gas injection. The midplane density is determined from a high spatial resolution Thomson scattering diagnostic at the midplane with power balance analysis to determine the separatrix location. The heat flux density is varied by scans of three parameters, auxiliary heating, toroidal field with fixed plasma current, and plasma current with fixed safety factor, q 95. The separatrix density just before divertor detachment onset is found to scale consistent with the two-point model when radiative dissipation is taken into account. The ratio of separatrix to pedestal density, n e,sep/n e,ped varies from  ⩽30% to  ⩾60% over the dataset, helping to resolve the conflicting scaling of core plasma density limit and divertor detachment onset. The scaling of the separatrix density at detachment onset is combined with H-mode power threshold scaling to obtain a scaling ratio of minimum n e,sep/n e,ped expected in future devices.

  18. Comparison between dominant NB and dominant IC heated ELMy H-mode discharges in JET

    Versloot, T. W.; Sartori, R.; Rimini, F.; de Vries, P. C.; Saibene, G.; Parail, V.; Beurskens, M. N. A.; Boboc, A.; Budny, R.; Crombe, K.; de la Luna, E.; Durodie, F.; Eich, T.; Giroud, C.; Kiptily, V.; Johnson, T.; Mantica, P.; Mayoral, M. L.; McDonald, D. C.; Monakhov, I.; Nave, M. F. F.; Voitsekhovitch, I.; Zastrow, K. D.


    The experiment described in this paper is aimed at characterization of ELMy H-mode discharges with varying momentum input, rotation, power deposition profiles and ion to electron heating ratio obtained by varying the proportion between ion cyclotron (IC) and neutral beam (NB) heating. The motivation

  19. [Plasma hormone concentrations in induced abortion with local prostaglandin administration in the 1st trimester].

    Rath, W; König, A; Ulbrich, R; Hilgers, R; Kuske, R; Kuhn, W


    Abortion was performed by curettage on 71 women with pregnancies between the 7th and the 13th week of gestation seven to eight hours after intracervical application of a tylose gel containing 3mg prostaglandin F2 alpha. Prior to the application of the prostaglandin and immediately before the surgical intervention a sonographic examination for determining the vitality of the pregnancy was carried out.--Plasma progesteron, estradiol and HPL levels were determined radioimmunologically prior to the application of prostaglandin, at four-hour intervals on the day of intervention, and 24, 48 and 72 hours after the intervention. In 22 women a complete or an incomplete abortion occurred; in two cases a blighted ovum was observed; 47 pregnancies, according to sonographic examination, remained intact until curettage. After seven to eight hours duration of the effect of the prostaglandin gel, progesterone levels were found to be reduced to 60.5 per cent and 17-beta-estradiol to 31.4 per cent of the initial values, whereas the HPL values fell below the specificity of the testing procedure (12.5 ng/ml). Comparative investigations of the pregnancies which, according to sonographic findings, remained intact until curettage and those which were aborted after the application of prostaglandin did not, in spite of low plasma progesterone and estradiol levels in the abortive group, reveal any statistically significant differences. The abortive effect--even with local application--of the prostaglandins was confirmed. Conclusions regarding the effective mechanism of the prostaglandins upon the fetoplacental unit and the function of the corpus luteum remain subject to speculation.

  20. EDITORIAL: Special issue containing papers presented at the 12th International Workshop on H-mode Physics and Transport Barriers Special issue containing papers presented at the 12th International Workshop on H-mode Physics and Transport Barriers

    Hahm, T. S.


    The 12th International Workshop on H-mode Physics and Transport Barriers was held at the Princeton Plasma Physics Laboratory, Princeton, New Jersey, USA between September 30 and October 2, 2009. This meeting was the continuation of a series of previous meetings which was initiated in 1987 and has been held bi-annually since then. Following the recent tradition at the last few meetings, the program was sub- divided into six sessions. At each session, an overview talk was presented, followed by two or three shorter oral presentations which supplemented the coverage of important issues. These talks were followed by discussion periods and poster sessions of contributed papers. The sessions were: Physics of Transition to/from Enhanced Confinement Regimes, Pedestal and Edge Localized Mode Dynamics, Plasma Rotation and Momentum Transport, Role of 3D Physics in Transport Barriers, Transport Barriers: Theory and Simulations and High Priority ITER Issues on Transport Barriers. The diversity of the 90 registered participants was remarkable, with 22 different nationalities. US participants were in the majority (36), followed by Japan (14), South Korea (7), and China (6). This special issue of Nuclear Fusion consists of a cluster of 18 accepted papers from submitted manuscripts based on overview talks and poster presentations. The paper selection procedure followed the guidelines of Nuclear Fusion which are essentially the same as for regular articles with an additional requirement on timeliness of submission, review and revision. One overview paper and five contributed papers report on the H-mode pedestal related results which reflect the importance of this issue concerning the successful operation of ITER. Four papers address the rotation and momentum transport which play a crucial role in transport barrier physics. The transport barrier transition condition is the main focus of other four papers. Finally, four additional papers are devoted to the behaviour and control of

  1. PREFACE: 1st International Symposium on Electrical Arc and Thermal Plasmas in Africa (ISAPA)

    Andre, Pascal; Koalaga, Zacharie


    Logos of the University of Ouagadougou, ISAPA and Universite Blaise Pascal Africa (especially Sub-Saharan Africa) is a continent where electrification is at a low level. However, the development of the electrical power sector is a prerequisite for the growth of other industrial activities, that is to say for the social and economic development of African countries. Consequently, a large number of electrification projects (rural electrification, interconnection of different country's grids) takes place in many countries. These projects need expertise and make Africa a continent of opportunity for companies in different domains for business and research: energy; energetic production, transmission, distribution and protection of electricity; the supply of cable; the construction, engineering and expertise in the field of solar and wind power. The first International Symposium on electrical Arc and thermal Plasma in Africa (ISAPA) was held for the first time in Ouagadougou, Burkina Faso to progress and develop the research of new physical developments, technical breakthroughs, and ideas in the fields of electrical production and electrical applications. The ISAPA aims to encourage the advancement of the science and applications of electrical power transformation in Africa by bringing together specialists from many areas in Africa and the rest of the world. Such considerations have led us to define a Scientific Committee including representatives from many countries. This first meeting was an innovative opportunity for researchers and engineers from academic and industrial sectors to exchange views and knowledge. Both fundamental aspects such as thermal plasma, electrical arc, diagnostics and applied aspects as circuit breakers, ICP analyses, photovoltaic energy conversion and alternative energies, as well as space applications were covered. The Laboratory of Material and Environment (LAME) from Ouagadougou University and the Laboratory of Electric Arc and Thermal

  2. Investigation of peeling-ballooning stability prior to transient outbursts accompanying transitions out of H-mode in DIII-D

    Eldon, D., E-mail: [University of California San Diego, 9500 Gilman Dr., La Jolla, California 92093-0964 (United States); Princeton University, Princeton, New Jersey 08543 (United States); Boivin, R. L.; Groebner, R. J.; Osborne, T. H.; Snyder, P. B.; Turnbull, A. D.; Burrell, K. H. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Tynan, G. R.; Boedo, J. A. [University of California San Diego, 9500 Gilman Dr., La Jolla, California 92093-0964 (United States); Kolemen, E. [Princeton University, Princeton, New Jersey 08543 (United States); Schmitz, L. [University of California Los Angeles, Los Angeles, California 90095-7099 (United States); Wilson, H. R. [University of York, Heslington, York YO10 5DD (United Kingdom)


    The H-mode transport barrier allows confinement of roughly twice as much energy as in an L-mode plasma. Termination of H-mode necessarily requires release of this energy, and the timescale of that release is of critical importance for the lifetimes of plasma facing components in next step tokamaks such as ITER. H-L transition sequences in modern tokamaks often begin with a transient outburst which appears to be superficially similar to and has sometimes been referred to as a type-I edge localized mode (ELM). Type-I ELMs have been shown to be consistent with ideal peeling ballooning instability and are characterized by significant (up to ∼50%) reduction of pedestal height on short (∼1 ms) timescales. Knowing whether or not this type of instability is present during H-L back transitions will be important of planning for plasma ramp-down in ITER. This paper presents tests of pre-transition experimental data against ideal peeling-ballooning stability calculations with the ELITE code and supports those results with secondary experiments that together show that the transient associated with the H-L transition is not triggered by the same physics as are type-I ELMs.

  3. Scaling of the Critical Beta for Onset of the m/n=2/1 Neoclassical Tearing Mode in Conventional H-Mode Discharges in DIII-D

    La Haye, R. J.; Petty, C. C.; Strait, E. J.


    While m/n=3/2 NTMs have been observed and studied in detail,(R.J. La Haye et al.), to be in the August 2000 Phys. Plasmas. their consequences are small compared to the m/n=2/1 mode which tends to lock, destroy the H-Mode and cause disruption. The 2/1 modes in DIII-D H-Mode discharges appear to be NTMs in that they are excited as beta is rising, are triggered by a sawtooth crash, ELM or both and have a nearly linear critical beta with rhoistar (the ion gyroradius normalized to the plasma minor radius). Analysis of a 2/1 database in DIII-D will be presented. Preliminary comparison to the polarization/ inertial theory,(H.R. Wilson et al.), Phys. Plasmas 3, 248 (1996). particularly of the key issue of island propagation in the local (q=2) E_r=0 quasi-neutrality frame, shows consistency with a stabilizing effect, i.e., a threshold.

  4. Efficient low-beta H-mode accelerating structures with PMQ focusing

    Kurennoy, Sergey S [Los Alamos National Laboratory; O' Hara, James F [Los Alamos National Laboratory; Olivas, Eric R [Los Alamos National Laboratory; Rybarcyk, Lawrence J [Los Alamos National Laboratory


    We are developing high-efficiency room-temperature RF accelerating structures for beam velocities in the range of a few percent of the speed of light by merging two well-known ideas: H-mode cavities and the transverse beam focusing with permanent-magnet quadrupoles (PMQ). Combining electromagnetic 3-D modeling with beam dynamics simulations and thermal-stress analysis, we have found that the H-mode structures with PMQ focusing provide a very efficient and practical accelerator for light-ion beams of considerable currents. Such accelerating structures following a short RFQ can be used in the front end of ion linacs or in stand-alone applications such as a compact deuteron-beam accelerator up to the energy of a few MeV.

  5. H-mode accelerating structures with permanent-magnet quadrupole beam focusing

    Kurennoy, S. S.; Rybarcyk, L. J.; O'Hara, J. F.; Olivas, E. R.; Wangler, T. P.


    We have developed high-efficiency normal-conducting rf accelerating structures by combining H-mode resonator cavities and a transverse beam focusing by permanent-magnet quadrupoles (PMQ), for beam velocities in the range of a few percent of the speed of light. The shunt impedance of interdigital H-mode (IH-PMQ) structures is 10-20 times higher than that of a conventional drift-tube linac, while the transverse size is 4-5 times smaller. Results of the combined 3D modeling—electromagnetic computations, multiparticle beam-dynamics simulations with high currents, and thermal-stress analysis—for an IH-PMQ accelerator tank are presented. The accelerating-field profile in the tank is tuned to provide the best propagation of a 50-mA deuteron beam using coupled iterations of electromagnetic and beam-dynamics modeling. Measurements of a cold model of the IH-PMQ tank show a good agreement with the calculations. Examples of cross-bar H-mode structures with PMQ focusing for higher beam velocities are also presented. H-PMQ accelerating structures following a short radio-frequency quadrupole accelerator can be used both in the front end of ion linacs or in stand-alone applications.

  6. Thermal instability explanation of similar density limits in gas fueled, DIII-D H-mode shots with different operating conditions

    Stacey, W. M.; Petrie, T. W.; Leonard, A. W.


    Recent experiments on DIII-D [J. L. Luxon, F. Batty, C. Baxi et al., Plasma Physics and Controlled Nuclear Fusion Research 1986 (International Atomic Energy Agency, Vienna, 1987), Vol. I, p. 159] examined the effect of different operating conditions ("open" and "closed" divertor geometry, active pumping, fueling location) on the maximum achievable density in gas fueled H-mode (high confinement mode) discharges. Several phenomena observed at these higher densities (≈0.8 the Greenwald density)—degradation in energy confinement, detachment of the core plasma from the divertor plate, multifaceted asymmetric radiation from edge formation—are found to be correlated with the predicted onset of various thermal instabilities in the plasma edge or divertor regions. The similarity of the maximum achievable densities under the different operating conditions can be related to a similarity of edge thermal instability characteristics.

  7. PREFACE: 15th Latin American Workshop on Plasma Physics (LAWPP 2014) and 21st IAEA TM on Research Using Small Fusion Devices (RUSFD)

    Iván Vargas-Blanco, V.; Herrera-Velázquez, J. Julio E.


    Written contributions from participants of the Joint 15th Latin American Workshop on Plasma Physics (LAWPP 2014) - 21st IAEA Technical Meeting on Research Using Small Fusion Devices (21st IAEA TM RUSFD). The International Advisory Committees of the 15th Latin American Workshop on Plasma Physics (LAWPP 2014) and the 21st IAEA TM on Research Using Small Fusion Devices (RUSFD), agreed to carry out together this Joint LAWPP 2014 - 21st RUSFD in San José, Costa Rica, on 27-31 January 2014. The Joint LAWPP 2014 - 21st RUSFD meeting, organized by the Instituto Tecnológico de Costa Rica, Universidad Nacional de Costa Rica, and Ad Astra Rocket Company in collaboration with the International Atomic Energy Agency (IAEA). The Latin American Workshop on Plasma Physics (LAWPP) is a series of events which has been held periodically since 1982, with the purpose of providing a forum in which the research of the Latin American plasma physics community can be displayed, as well as fostering collaborations among plasma scientists within the region and with researchers from the rest of the world. Recognized plasma scientists from developed countries are specially invited to the meeting to present the state of the art on several "hot" topics related to plasma physics. It is an open meeting, with an International Advisory Committee, in which the working language is English. It was firstly held in 1982 in Cambuquira, Brazil, followed by workshops in Medellín, Colombia (1985), Santiago de Chile, Chile (1988), Buenos Aires, Argentina (1990), Mexico City, Mexico (1992), Foz do Iguaçu, Brazil (1994, combined with the International Congress on Plasma Physics (ICPP)), Caracas, Venezuela (1997), Tandil, Argentina (1998), La Serena, Chile (2000), Sao Pedro, Brazil (2003), Mexico City, Mexico (2005), Caracas, Venezuela (2007), Santiago de Chile, Chile (2010, combined with the ICPP) and Mar de Plata, Argentina (2011). The 21st IAEA TM on Research Using Small Fusion Devices is an ideal forum for

  8. Non-power law scaling for access to the H-mode in tokamaks via symbolic regression

    Murari, A.; Lupelli, I.; Gelfusa, M.; Gaudio, P.


    The power threshold (PThresh) to access the H-mode in tokamaks remains a subject of active research, because up to now no theoretical relation has proved to be general enough to reliably interpret the L-H transition. Over the last few decades, much effort has therefore been devoted to deriving empirical scalings, assuming ‘a priori’ a power-law model structure. In this paper, an empirical scaling of PThresh without any a priori assumption about the model structure, i.e. about the functional form, is derived. Symbolic regression via genetic programming is applied to the latest version multi-machine International Tokamak Physics Activity International Global Power Threshold Data Base of validated ITER-like discharges. The derived model structure of the scaling for the global database is not in a power law form and includes a term that indicates saturation of PThresh with the strength of the toroidal field, plasma density and elongation. Furthermore, the single machine analysis of the database for the most representative machines of the international fusion scientific program demonstrates that the model structures are similar but the model parameters are different. The better extrapolation capability of the identified model structures with the proposed methodology is verified with a specific analysis of JET data at two different current regimes. The PThresh values extrapolated to ITER using the derived empirical model structures are a factor of two lower than those of traditional scaling laws and are predicted with a significantly better confidence.

  9. Fast measurements of the electron temperature and parallel heat flux in ELMy H-mode on the COMPASS tokamak

    Adamek, J.; Seidl, J.; Komm, M.; Weinzettl, V.; Panek, R.; Stöckel, J.; Hron, M.; Hacek, P.; Imrisek, M.; Vondracek, P.; Horacek, J.; Devitre, A.; the COMPASS Team


    We report the latest results on fast measurements of the electron temperature and parallel heat flux in the COMPASS tokamak scrape-off layer (SOL) and divertor region during ELMy H-mode plasmas. The system of ball-pen and Langmuir probes installed on the divertor target, the horizontal reciprocating manipulator and the fast data-acquisition system with sampling frequency rate f  =  5 MSa s-1 allow us to measure the electron temperature and parallel heat flux during inter-ELM and ELM periods with high temporal resolution. The filamentary structure of the electron temperature and parallel heat flux was observed during ELMs in the SOL as well as in the divertor region. The position of the filaments within ELMs is not regular and therefore the resulting conditionally averaged ELM neglects the peak values of the electron temperature and parallel heat flux. We have found a substantial difference between the value of the radial power decay length in the inter-ELM period λ q,inter  =  2.5 mm and the decay length of the peak ELM heat flux λ q,ELM  =  13.1 mm. The decay length of the ELM energy density was found to be λ E,ELM  =  5.4 mm.

  10. The transition mechanisms of the E to H mode and the H to E mode in an inductively coupled argon-mercury mixture discharge

    Zhang, Xiao; Yu, Peng-Cheng; Liu, Yu; Zheng, Zhe; Xu, Liang; Wang, Pi; Cao, Jin-Xiang, E-mail: [CAS Key Laboratory of Geospace Environment, Modern Physics Department, University of Science and Technology of China, Hefei, Anhui 230026 (China)


    In our experiment, the transition points between the two operational modes of capacitive coupling (E mode) and inductive coupling (H mode) were investigated at a wide range of mercury vapor pressures in an inductively coupled plasma, varying with the input radio-frequency powers and the total filling pressures (10 Pa–30 Pa). The electron temperatures were calculated versus with the mercury vapor pressures for different values of the total filling pressures. The transition power points and electron density also were measured in this study. It is shown that the transition powers, whether the E to H mode transition or the H to E mode transition, are lower than that of the argon discharge, and these powers almost increase with the mercury vapor pressure rising. However, the transition electron density follows an inverse relationship with the mercury vapor pressures compared with the transition powers. In addition, at the lower pressures and higher mercury vapor pressures, an inverse hysteresis was observed clearly, which did not appear in the argon gas plasma. We suggest that all these results are attributed to the electron-neutral collision frequency changed with the additional mercury vapor pressures.

  11. Pedestal properties of H-modes with negative triangularity using the EPED-CH model

    Merle, A.; Sauter, O.; Medvedev, S. Yu


    The EPED model has been designed to predict the pedestal height and width from a minimal set of parameters and using the stability of the pedestal region for global MHD peeling-ballooning (P-B) modes as well as local kinetic ballooning modes (KBMs). This approach has been validated for type-I ELMy H-modes and quiescent H-modes (QH) but can also be used for other types of H-modes where it usually sets an upper limit on the achievable pedestal height. Using the recently developed EPED-like model called EPED-CH and based on the equilibrium codes CHEASE and CAXE and the MHD stability code KINX, we investigate in this work the effect of negative triangularity on the pedestal structure. Our simulation results confirm the experimental results from TCV where a reduction of the pedestal height was observed when going from positive to negative top triangularity. This was interpreted as a degradation of the peeling-ballooning stability due to the closed access to the second stability region for ballooning modes in the case of negative triangularity. This effect is further enhanced by the coupling to the KBM stability criterion in EPED simulations. The novel concept of the negative triangularity tokamak (a DEMO-sized machine) is also investigated. Again a strong reduction of the pedestal height and width is observed going from positive to negative triangularity for up-down symmetric equilibria. The pedestal height is also reduced going to more up-down asymmetric cases. The beneficial effect of the global β value on the pedestal height, which is linked to the second stability access, is strongly reduced for negative triangularity.

  12. Interdigital H -mode drift-tube linac design with alternative phase focusing for muon linac

    Otani, M.; Mibe, T.; Yoshida, M.; Hasegawa, K.; Kondo, Y.; Hayashizaki, N.; Iwashita, Y.; Iwata, Y.; Kitamura, R.; Saito, N.


    We have developed an interdigital H-mode (IH) drift-tube linac (DTL) design with an alternative phase focusing (APF) scheme for a muon linac, in order to measure the anomalous magnetic moment and electric dipole moment (EDM) of muons at the Japan Proton Accelerator Research Complex (J-PARC). The IH-DTL accelerates muons from β =v /c =0.08 to 0.28 at an operational frequency of 324 MHz. The output beam emittances are calculated as 0.315 π and 0.195 π mm mrad in the horizontal and vertical directions, respectively, which satisfies the experimental requirement.

  13. The role of turbulence-flow interactions in L- to H-mode transition dynamics: recent progress

    Schmitz, L.


    Recent experimental and simulation work has substantially advanced the understanding of L-mode plasma edge turbulence and plasma flows and their mutual interaction across the L-H transition. Flow acceleration and E   ×   B shear flow amplification via the turbulent Reynolds stress have been directly observed in multiple devices, using multi-tip probe arrays, Doppler backscattering, beam emission spectroscopy, and gas puff imaging diagnostics. L-H transitions characterized by limit-cycle oscillations (LCO) allow probing of the trigger dynamics and the synergy of turbulence-driven and pressure-gradient-driven flows with high spatio-temporal resolution. L-mode turbulent structures exhibit characteristic changes in topology (tilting) and temporal and radial correlation preceding the L-H transition. Long-range toroidal flow correlations increase preceding edge-transport-barrier formation. The energy transfer from the turbulence spectrum to large-scale axisymmetric flows has been quantified in L-LCO and fast L-H transitions in several devices. After formation of a transient barrier, the increasing ion pressure gradient (via the E   ×   B flow shear associated with diamagnetic flow) sustains fluctuation suppression and secures the transition to H-mode. Heuristic models of the L-H trigger dynamics have progressed from 0D predator-prey models to 1D extended models, including neoclassical ion flow-damping and pressure-gradient evolution. Initial results from 2D and 3D reduced fluid models have been obtained for high-collisionality regimes.

  14. Momentum transport studies in JET H-mode discharges with an enhanced toroidal field ripple

    De Vries, P C; Howell, D H; Giroud, C; Parail, V [EURATOM/CCFE Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Versloot, T W [FOM institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, PO Box 1207, Nieuwegein (Netherlands); Salmi, A [Association Euratom-Tekes, Helsinki University of Technology, PO Box 4100, 02015 TKK (Finland); Hua, M-D [Imperial College, SW7 2BY, London (United Kingdom); Saibene, G [Fusion for Energy Joint Undertaking, 0819 Barcelona (Spain); Tala, T, E-mail: [Association Euratom-Tekes, VTT, PO Box 1000, 02044 VTT (Finland)


    In this study, enhancement of the toroidal field (TF) ripple has been used as a tool in order to reveal the impact of the momentum pinch on the rotation profiles in H-mode JET discharges. The analysis showed that flatter rotation profiles were obtained in discharges with a high TF ripple, attributed to a smaller inward momentum convection. An average inward momentum pinch of approximately V{sub p} {approx} 3.4 m s{sup -1} and a normalized pinch value of RV{sub p}/{chi} {approx} 6.6 could explain the observation. The data show that the momentum at the edge affects the peaking of the rotation and momentum density profiles. Under the assumption that the heat and momentum diffusivities are equal, an estimate of the levels of the momentum pinch in all discharges in the JET rotation database was made. For H-mode discharge these ranged from 0.3 m s{sup -1} < V{sub p} < 17 m s{sup -1}, with 2 < RV{sub p}/{chi} < 10. A larger momentum pinch was found in discharges with a smaller density profile gradient length, i.e. a more peaked density profile.

  15. H-mode accelerating structures with PMQ focusing for low-beta ion beams

    Kurennoy, Sergey S [Los Alamos National Laboratory; O' Hara, James F [Los Alamos National Laboratory; Olivas, Eric R [Los Alamos National Laboratory; Rybarcyk, Lawrence J [Los Alamos National Laboratory


    We are developing high-efficiency normal-conducting RF accelerating structures based on inter-digital H-mode (IH) cavities and the transverse beam focusing with permanent-magnet quadrupoles (PMQ), for beam velocities in the range of a few percent of the speed of light. Such IH-PMQ accelerating structures following a short RFQ can be used in the front end of ion linacs or in stand-alone applications, e.g. a compact deuteron-beam accelerator up to the energy of several MeV. Results of combined 3-D modeling for a full IH-PMQ accelerator tank - electromagnetic computations, beam-dynamics simulations with high currents, and thermal-stress analysis - are presented. The accelerating field profile in the tank is tuned to provide the best beam propagation using coupled iterations of electromagnetic and beam-dynamics modeling. A cold model of the IH-PMQ tank is being manufactured.

  16. NIMROD modeling of quiescent H-mode: reconstruction considerations and saturation mechanism

    King, J. R.; Burrell, K. H.; Garofalo, A. M.; Groebner, R. J.; Kruger, S. E.; Pankin, A. Y.; Snyder, P. B.


    The extended-MHD NIMROD code (Sovinec and King 2010 J. Comput. Phys. 229 5803) models broadband-MHD activity from a reconstruction of a quiescent H-mode shot on the DIII-D tokamak (Luxon 2002 Nucl. Fusion 42 614). Computations with the reconstructed toroidal and poloidal ion flows exhibit low-{{n}φ} perturbations ({{n}φ}≃ 1 -5) that grow and saturate into a turbulent-like MHD state. The workflow used to project the reconstructed state onto the NIMROD basis functions re-solves the Grad-Shafranov equation and extrapolates profiles to include scrape-off-layer currents. Evaluation of the transport from the turbulent-like MHD state leads to a relaxation of the density and temperature profiles.

  17. Elevated Plasma IL-38 Concentrations in Patients with Acute ST-Segment Elevation Myocardial Infarction and Their Dynamics after Reperfusion Treatment

    Yucheng Zhong


    Full Text Available Objective. Recent studies suggest that IL-38 is associated with autoimmune diseases. Furthermore, IL-38 is expressed in human atheromatous plaque. However, the plasma levels of IL-38 in patients with ST-segment elevation myocardial infarction (STEMI have not yet to be investigated. Methods. On admission, at 24 h, at 48 h, and at 7 days, plasma IL-38, C-reactive protein (CRP, cardiac troponin I (cTNI, and N-terminal of the prohormone brain natriuretic peptide (NT-proBNP levels were measured and IL-38 gene in peripheral blood mononuclear cells (PBMCs was detected in STEMI patients. Results. The results showed that plasma IL-38 levels and IL-38 gene expression in PBMCs were significantly increased in STEMI patients compared with control group and were time dependent, peaked at 24 h. In addition, plasma IL-38 levels were dramatically reduced in patients with reperfusion treatment compared with control group. Similar results were also demonstrated with CRP, cTNI, and NT-proBNP levels. Furthermore, IL-38 levels were found to be positively correlated with CRP, cTNI, and NT-proBNP and be weakly negatively correlated with left ventricular ejection fraction (LVEF in STEMI patients. Conclusions. The results indicate that circulating IL-38 is a potentially novel biomarker for patients with STEMI and IL-38 might be a new target for MI study.

  18. Stability of Microturbulent Drift Modes during Internal Transport Barrier Formation in the Alcator C-Mod Radio Frequency Heated H-mode

    M.H. Redi; C.L. Fiore; W. Dorland; D.R. Mikkelsen; G. Rewoldt; P.T. Bonoli; D.R. Ernst; J.E. Rice; S.J. Wukitch


    Recent H-mode experiments on Alcator C-Mod [I.H. Hutchinson, et al., Phys. Plasmas 1 (1994) 1511] which exhibit an internal transport barrier (ITB), have been examined with flux tube geometry gyrokinetic simulations, using the massively parallel code GS2 [M. Kotschenreuther, G. Rewoldt, and W.M. Tang, Comput. Phys. Commun. 88 (1995) 128]. The simulations support the picture of ion/electron temperature gradient (ITG/ETG) microturbulence driving high xi/ xe and that suppressed ITG causes reduced particle transport and improved ci on C-Mod. Nonlinear calculations for C-Mod confirm initial linear simulations, which predicted ITG stability in the barrier region just before ITB formation, without invoking E x B shear suppression of turbulence. Nonlinear fluxes are compared to experiment, which both show low heat transport in the ITB and higher transport within and outside of the barrier region.

  19. Radial transport in the far scrape-off layer of ASDEX upgrade during L-mode and ELMy H-mode

    Ionita, C.; Naulin, Volker; Mehlmann, F.


    The radial turbulent particle flux and the Reynolds stress in the scrape-off layer (SOL) of ASDEX Upgrade were investigated for two limited L-mode (low confinement) and one ELMy H-mode (high confinement) discharge. A fast reciprocating probe was used with a probe head containing five Langmuir...... potentials of two probes on the same poloidal meridian. In both cases, equal electron temperatures on all probe pins had to be assumed. Of the other pins one was biased to ion saturation (-70 V), whereas one was swept to record the current-voltage characteristic. A detailed statistical analysis of the plasma...... probes. One of the probe pins was protruding radially above the other pins. The radial electric field component was derived from the difference of the floating potentials of the protruding pin and another pin nearby. The poloidal electric field component was derived from the difference of the floating...

  20. Endoplasmic reticulum stress mediating downregulated StAR and 3-beta-HSD and low plasma testosterone caused by hypoxia is attenuated by CPU86017-RS and nifedipine

    Liu Gui-Lai


    Full Text Available Abstract Background Hypoxia exposure initiates low serum testosterone levels that could be attributed to downregulated androgen biosynthesizing genes such as StAR (steroidogenic acute regulatory protein and 3-beta-HSD (3-beta-hydroxysteroid dehydrogenase in the testis. It was hypothesized that these abnormalities in the testis by hypoxia are associated with oxidative stress and an increase in chaperones of endoplasmic reticulum stress (ER stress and ER stress could be modulated by a reduction in calcium influx. Therefore, we verify that if an application of CPU86017-RS (simplified as RS, a derivative to berberine could alleviate the ER stress and depressed gene expressions of StAR and 3-beta-HSD, and low plasma testosterone in hypoxic rats, these were compared with those of nifedipine. Methods Adult male Sprague-Dawley rats were randomly divided into control, hypoxia for 28 days, and hypoxia treated (mg/kg, p.o. during the last 14 days with nifedipine (Nif, 10 and three doses of RS (20, 40, 80, and normal rats treated with RS isomer (80. Serum testosterone (T and luteinizing hormone (LH were measured. The testicular expressions of biomarkers including StAR, 3-beta-HSD, immunoglobulin heavy chain binding protein (Bip, double-strand RNA-activated protein kinase-like ER kinase (PERK and pro-apoptotic transcription factor C/EBP homologous protein (CHOP were measured. Results In hypoxic rats, serum testosterone levels decreased and mRNA and protein expressions of the testosterone biosynthesis related genes, StAR and 3-beta-HSD were downregulated. These changes were linked to an increase in oxidants and upregulated ER stress chaperones: Bip, PERK, CHOP and distorted histological structure of the seminiferous tubules in the testis. These abnormalities were attenuated significantly by CPU86017-RS and nifedipine. Conclusion Downregulated StAR and 3-beta-HSD significantly contribute to low testosterone in hypoxic rats and is associated with ER stress

  1. H-mode Accelerating Structures with PMQ Focusing for Low-Beta Beams

    Kurennoy, Sergey S. [Los Alamos National Laboratory; O' Hara, James F. [Los Alamos National Laboratory; Olivas, Eric R. [Los Alamos National Laboratory; Rybarcyk, Lawrence J. [Los Alamos National Laboratory


    We report on results of the project developing high-efficiency normal-conducting RF accelerating structures based on inter-digital H-mode (IH) cavities and the transverse beam focusing with permanent-magnet quadrupoles (PMQ), for beam velocities in the range of a few percent of the speed of light. The shunt impedance of IH-PMQ structures is 10-20 times higher than that of a conventional drift-tube linac, while the transverse size is 4-5 times smaller. The H-PMQ accelerating structures following a short RFQ can be used both in the front end of ion linacs or in stand-alone applications. Results of the combined 3-D modeling -- electromagnetic computations, beam-dynamics simulations with high currents, and thermal-stress analysis -- for a full IH-PMQ accelerator tank are presented. The accelerating field profile in the tank is tuned to provide the best propagation of a 50-mA deuteron beam using coupled iterations of EM and beamdynamics modeling. Multi-particle simulations withParmela and CST Particle Studio have been used to confirm the design. Measurement results of a cold model of the IH-PMQ tank are presented.

  2. Development of superconducting crossbar-H-mode cavities for proton and ion accelerators

    F. Dziuba


    Full Text Available The crossbar-H-mode (CH structure is the first superconducting multicell drift tube cavity for the low and medium energy range operated in the H_{21} mode. Because of the large energy gain per cavity, which leads to high real estate gradients, it is an excellent candidate for the efficient acceleration in high power proton and ion accelerators with fixed velocity profile. A prototype cavity has been developed and tested successfully with a gradient of 7  MV/m. A few new superconducting CH cavities with improved geometries for different high power applications are under development at present. One cavity (f=325  MHz, β=0.16, seven cells is currently under construction and studied with respect to a possible upgrade option for the GSI UNILAC. Another cavity (f=217  MHz, β=0.059, 15 cells is designed for a cw operated energy variable heavy ion linac application. Furthermore, the EUROTRANS project (European research program for the transmutation of high level nuclear waste in an accelerator driven system, 600 MeV protons, 352 MHz is one of many possible applications for this kind of superconducting rf cavity. In this context a layout of the 17 MeV EUROTRANS injector containing four superconducting CH cavities was proposed by the Institute for Applied Physics (IAP Frankfurt. The status of the cavity development related to the EUROTRANS injector is presented.

  3. L to H mode transition: parametric dependencies of the temperature threshold

    Bourdelle, C.; Chôné, L.; Fedorczak, N.; Garbet, X.; Beyer, P.; Citrin, J.; Delabie, E.; Dif-Pradalier, G.; Fuhr, G.; Loarte, A.; Maggi, C. F.; Militello, F.; Sarazin, Y.; Vermare, L.; Contributors, JET


    The L to H mode transition occurs at a critical power which depends on various parameters, such as the magnetic field, the density, etc. Experimental evidence on various tokamaks (JET, ASDEX-Upgrade, DIII-D, Alcator C-Mod) points towards the existence of a critical temperature characterizing the transition. This criterion for the L-H transition is local and is therefore easier to be compared to theoretical approaches. In order to shed light on the mechanisms of the transition, simple theoretical ideas are used to derive a temperature threshold (Tth). They are based on the stabilization of the underlying turbulence by a mean radial electric field shear. The nature of the turbulence varies as the collisionality decreases, from resistive ballooning modes to ion temperature gradient and trapped electron modes. The obtained parametric dependencies of the derived Tth are tested versus magnetic field, density, effective charge. Various robust experimental observations are reproduced, in particular Tth increases with magnetic field B and increases with density below the density roll-over observed on the power threshold.

  4. CLUSTER: A high-frequency H-mode coupled cavity linac for low and medium energies

    Amaldi, Ugo [TERA Foundation, Via Puccini 11, 28100 Novara (Italy); University of Milano Bicocca, Milan (Italy)], E-mail:; Citterio, Alessandro; Crescenti, Massimo; Giuliacci, Arianna; Tronci, Cesare; Zennaro, Riccardo [TERA Foundation, Via Puccini 11, 28100 Novara (Italy)


    An innovative linear accelerating structure is proposed which is particularly suited for low-current hadrontherapy applications but can also conveniently substitute the conventional proton linacs at present considered for Accelerator Driven Systems and neutrino and muon factories. Its two main features are compactness and good power efficiency at low-medium beam velocities (0.05{<=}{beta}{<=}0.5). The first is achieved through a high working frequency and a consequent high accelerating gradient, the second is obtained by coupling several H-mode cavities together. The structure was dubbed CLUSTER for 'Coupled-cavity Linac USing Transverse Electric Radial field'. To compare the performance of this structure with other hadrontherapy linac designs involving high frequencies, a conceptual study has been performed for an operating frequency of 3 GHz. Moreover, a proof of principle has been obtained through RF measurements on a prototype operating at 1 GHz. An accelerator complex using a CLUSTER linac is also considered for protontherapy purposes. This total accelerator complex, called 'cyclinac', uses a commercial cyclotron as an injector to a high-frequency and high-gradient linac.

  5. Alternating-Phase-Focused Linac with Interdigital H-Mode Structure for Medical Injectors

    Iwata, Yoshiyuki; Fujimoto, Tetsuya; Fujisawa, Takashi; Furukawa, Takuji; Hojo, Satoru; Honma, T; Kanazawa, Mitsutaka; Kapin, Valery; Mitsumoto, Toshinori; Miyahara, Nobuyuki; Murakami, Takeshi; Muramatsu, Masayuki; Noda, Koji; Ogawa, Hirotsugu; Ogawa, Hiroyuki; Torikoshi, Masami; Tsutsui, Hiroshi; Yamada, Satoru; Yamamoto, Kazuo


    Tumor therapy using Heavy Ion Medical Accelerator in Chiba (HIMAC) has been performed at National Institute of Radiological Sciences (NIRS). With the successful clinical results over ten years, a project on developing compact accelerators has been started. To design these compact accelerators, a size of an injector as well as construction and operation costs plays an important role. To satisfy these requirements, we propose a compact injector consisting of a RFQ and Interdigital H-mode Drift-Tube-Linac (IH-DTL) having the resonant frequency of 200 MHz. The injector will accelerate carbon ion up to 4.0 AMeV. For the beam focusing of the IH-DTL, the method of Alternating-Phase-Focusing was employed. With the IH structure and rather high operating-frequency, the size of the cavities is compact; the radius is approximately 0.4 m, and the length of the RFQ and IH-DTL will be 2.5m and 3.5m respectively. The fabrication of the RFQ is in progress. For the IH-DTL, the full-scale model was fabricated. With the encourag...

  6. Identification of new turbulence contributions to plasma transport and confinement in spherical tokamak regime

    Wang, W. X.; Ethier, S.; Ren, Y.; Kaye, S.; Chen, J.; Startsev, E.; Lu, Z.; Li, Z. Q.


    Highly distinct features of spherical tokamaks (ST), such as National Spherical Torus eXperiment (NSTX) and NSTX-U, result in a different fusion plasma regime with unique physics properties compared to conventional tokamaks. Nonlinear global gyrokinetic simulations critical for addressing turbulence and transport physics in the ST regime have led to new insights. The drift wave Kelvin-Helmholtz (KH) instability characterized by intrinsic mode asymmetry is identified in strongly rotating NSTX L-mode plasmas. While the strong E ×B shear associated with the rotation leads to a reduction in KH/ion temperature gradient turbulence, the remaining fluctuations can produce a significant ion thermal transport that is comparable to the experimental level in the outer core region (with no "transport shortfall"). The other new, important turbulence source identified in NSTX is the dissipative trapped electron mode (DTEM), which is believed to play little role in conventional tokamak regime. Due to the high fraction of trapped electrons, long wavelength DTEMs peaking around kθρs˜0.1 are destabilized in NSTX collisionality regime by electron density and temperature gradients achieved there. Surprisingly, the E ×B shear stabilization effect on DTEM is remarkably weak, which makes it a major turbulence source in the ST regime dominant over collisionless TEM (CTEM). The latter, on the other hand, is subject to strong collisional and E ×B shear suppression in NSTX. DTEM is shown to produce significant particle, energy and toroidal momentum transport, in agreement with experimental levels in NSTX H-modes. Moreover, DTEM-driven transport in NSTX parametric regime is found to increase with electron collision frequency, providing one possible source for the scaling of confinement time observed in NSTX H-modes. Most interestingly, the existence of a turbulence-free regime in the collision-induced CTEM to DTEM transition, corresponding to a minimum plasma transport in advanced ST

  7. Pregnancy associated plasma protein A, a novel, quick, and sensitive marker in ST-elevation myocardial infarction

    Iversen, Kasper K; Teisner, Ane S; Teisner, Børge


    Traditional biomarkers in acute coronary syndromes reflect myocardial necrosis but not the underlying arteriosclerotic disease. Pregnancy-associated plasma protein A (PAPP-A) is a new biomarker in acute coronary syndromes that detects vulnerable plaques in arteriosclerotic disease and identifies ...

  8. H-mode pedestal characteristics, ELMs, and energy confinement in ITER shape discharges on DIII-D

    Osborne, T.H.; Groebner, R.J.; Lao, L.L.; Leonard, A.W.; Miller, R.L.; Thomas, D.M.; Waltz, R.E. [General Atomics, San Diego, CA (United States); Maingi, R. [Oak Ridge National Lab., TN (United States); Porter, G.D. [Lawrence Livermore National Lab., CA (United States)


    The H-mode confinement enhancement factor, H, is found to be strongly correlated with the height of the edge pressure pedestal in ITER shape discharges. In discharges with Type I ELMs the pedestal pressure is set by the maximum pressure gradient before the ELM and the width of the H-mode transport barrier. The pressure gradient before Type I ELMs is found to scale as would be expected for a stability limit set by ideal ballooning modes, but with values significantly in excess of that predicted by stability code calculations. The width of the H-mode transport barrier is found to scale equally well with pedestal P(POL)(2/3) or B(POL)(1/2). The improved H value in high B(POL) discharges may be due to a larger edge pressure gradient and wider H-mode transport barrier consistent with their higher edge ballooning mode limit. Deuterium puffing is found to reduce H consistent with the smaller pedestal pressure which results from the reduced barrier width and critical pressure gradient. Type I ELM energy loss is found to be proportional to the change in the pedestal energy.

  9. Effect of ELMs on rotation and momentum confinement in H-mode discharges in JET

    Versloot, T.W.; de Vries, P.C.; Giroud, C.


    The loss of plasma toroidal angular momentum and thermal energy by edge localized modes (ELMs) has been studied in JET. The analysis shows a consistently larger drop in momentum in comparison with the energy loss associated with the ELMs. This difference originates from the large reduction...... in angular frequency at the plasma edge, observed to penetrate into the plasma up to r/a ~ 0.65 during large type-I ELMs. As a result, the time averaged angular frequency is lowered near the top of the pedestal with increasing ELM frequency, resulting in a significant drop in thermal Mach number at the edge...... for momentum in combination with the observed longer build-up time for the momentum density at the plasma edge....

  10. Effect of ELMs on rotation and momentum confinement in H-mode discharges in JET

    Versloot, T. W.; de Vries, P. C.; Giroud, C.; Hua, M. D.; Beurskens, M. N. A.; Brix, M.; Eich, T.; de la Luna, E.; Tala, T.; Naulin, V.; Zastrow, K. D.


    The loss of plasma toroidal angular momentum and thermal energy by edge localized modes (ELMs) has been studied in JET. The analysis shows a consistently larger drop in momentum in comparison with the energy loss associated with the ELMs. This difference originates from the large reduction in angula

  11. One-dimensional modelling of limit-cycle oscillation and H-mode power scaling

    Wu, Xingquan; Xu, Guosheng; Wan, Baonian


    To understand the connection between the dynamics of microscopic turbulence and the macroscale power scaling in the L-I-H transition in magnetically confined plasmas, a new time-dependent, one-dimensional (in radius) model has been developed. The model investigates the radial force balance equati...

  12. Piloted Evaluation of the H-Mode, a Variable Autonomy Control System, in Motion-Based Simulation

    Goodrich, Kenneth H.; Schutte, Paul C.; Williams, Ralph A.


    As aircraft become able to autonomously respond to a range of situations with performance surpassing human operators, we are compelled to look for new methods that help understand their use and guide the design of new, more effective forms of automation and interaction. The "H-mode" is one such method and is based on the metaphor of a well-trained horse. The concept allows the pilot to manage a broad range of control automation functionality, from augmented manual control to FMS-like coupling and automation initiated actions, using a common interface system and easily learned set of interaction skills. The interface leverages familiar manual control interfaces (e.g., the control stick) and flight displays through the addition of contextually dependent haptic-multimodal elements. The concept is relevant to manned and remotely piloted vehicles. This paper provides an overview of the H-mode concept followed by a presentation of the results from a recent evaluation conducted in a motion-based simulator. The evaluation focused on assessing the overall usability and flying qualities of the concept with an emphasis on the effects of turbulence and cockpit motion. Because the H-mode results in interactions between traditional flying qualities and management of higher-level flight path automation, these effects are of particular interest. The results indicate that the concept may provide a useful complement or replacement to conventional interfaces, and retains the usefulness in the presence of turbulence and motion.

  13. A change of H-mode dynamics due to edge electric field shear

    Toda, Shinichiro; Itoh, Sanae [Kyushu Univ., Fukuoka (Japan)


    An extended model theory for Edge Localized Modes (ELMs) is presented with inclusion of the effects of the radial electric field shear, E`{sub r}, for high temperature plasmas in tokamaks. The dynamic model consists of an electric bifurcation model for the L/H transition, which contains a hysteresis characteristic due to E`{sub r}, and of a dynamic transport equation for the plasma gradient parameter. The self-generated oscillation is found to occur even if the effects of E`{sub r} are included: in addition to those of the radial electric field. The condition for the occurrence of a self-generated oscillation is examined. The wider region in the parameter space is found for the case with a negative electric field shear than for the case with a positive one. (author)

  14. Change in the H-mode dynamics due to torque conditions

    Toda, Shinichiro; Itoh, Sanae-I.; Kubota, Tetsuyuki; Yamaguchi, Hiroki [Kyushu Univ., Kasuga (Japan); Fukuyama, Atsushi [Okayama Univ. (Japan); Itoh, Kimitaka [National Inst. for Fusion Science, Nagoya (Japan)


    Poloidal rotation balance equation is obtained to have various bifurcation types of the solutions when various loss mechanisms are considered in tokamak plasmas. L/H transition in medium sized devices is predicted to be hard type and that in large sized devices tends to become soft type. Ion loss due to bulk viscosity found to be negligible compared to ion loss cone loss for the typical parameter regime of tokamaks. 7 refs., 4 figs., 1 tab.

  15. Equatorial ionospheric plasma drifts and O+ concentration enhancements associated with disturbance dynamo during the 2015 St. Patrick's Day magnetic storm

    Huang, Chao-Song; Wilson, Gordon R.; Hairston, Marc R.; Zhang, Yongliang; Wang, Wenbin; Liu, Jing


    Disturbance dynamo is an important dynamic process during magnetic storms. However, very few direct observations of dynamo-induced plasma drifts and ion composition changes in the equatorial ionosphere are available. In this study, we use measurements of the Defense Meteorological Satellite Program (DMSP) satellites to identify the characteristics of the disturbance dynamo process in the topside equatorial ionosphere near dawn during the magnetic storm with a minimum Dst of -223 nT on 17 March 2015. Data from four DMSP satellites with equatorial crossings at 0245, 0430, 0630, and 0730 LT are available for this case. The dynamo process was first observed in the postmidnight sector 3-4.7 h after the beginning of the storm main phase and lasted for 31 h, covering the second storm intensification and the initial 20 h of the recovery phase. The dynamo vertical ion drift was upward (up to 150-200 m s-1) in the postmidnight sector and downward (up to ~80 m s-1) in the early morning sector. The dynamo zonal ion drift was westward at these locations and reached ~100 m s-1. The dynamo process caused large enhancements of the O+ concentration (the ratio of the oxygen ion density to the total ion density) at the altitude of 840 km near dawn. The O+ concentration increased from below 60% during the prestorm period to 80-90% during the storm time. More specifically, the O+ density was increased, and the H+ density was decreased. The variations of the O+ concentration were well correlated with the vertical ion drift.

  16. The Dependence of H-mode Energy Confinement and Transport on Collisionality in NSTX

    Kaye, S. M.; Gerhardt, S.; Guttenfelder, W.; Maingi, R.; Bell, R. E.; Diallo, A.; LeBlanc, B. P.; Podesta, M.


    Understanding the dependence of confi nement on collisionality in tokamaks is important for the design of next-step devices, which will operate at collisionalities at least one order of magnitude lower than in present generation. A wide range of collisionality has been obtained in the National Spherical Torus Experiment (NSTX) by employing two different wall conditioning techniques, one with boronization and between-shot helium glow discharge conditioning (HeGDC+B), and one using lithium evaporation (Li EVAP). Previous studies of HeGDC+B plasmas indicated a strong and favorable dependence of normalized con nement on collisionality. Discharges with lithium conditioning discussed in the present study gen- erally achieved lower collisionality, extending the accessible range of collisionality by almost an order of unity. While the confinement dependences on dimensional, engineering variables of the HeGDC+B and Li EVAP datasets differed, collisionality was found to unify the trends, with the lower collisionality lithium conditioned discharges extending the trend of increasing normalized confi nement time with decreasing collisionality when other dimension less variables were held as fi xed as possible. This increase of confi nement with decreasing collisionality was driven by a large reduction in electron transport in the outer region of the plasma. This result is consistent with gyrokinetic calculations that show microtearing and Electron Temperature Gradient modes to be more stable for the lower collisionality discharges. Ion transport, near neoclassical at high collisionality, became more anomalous at lower collisionality, possibly due to the growth of hybrid TEM/KBM modes in the outer regions of the plasma.

  17. The Dependence of H-mode Energy Confinement and Transport on Collisionality in NSTX

    Kaye, S. M.; Gerhardt, S.; Guttenfelder, W.; Maingi, R.; Bell, R. E.; Diallo, A.; LeBlanc, B. P.; Podesta, M.


    Understanding the dependence of confi nement on collisionality in tokamaks is important for the design of next-step devices, which will operate at collisionalities at least one order of magnitude lower than in present generation. A wide range of collisionality has been obtained in the National Spherical Torus Experiment (NSTX) by employing two different wall conditioning techniques, one with boronization and between-shot helium glow discharge conditioning (HeGDC+B), and one using lithium evaporation (Li EVAP). Previous studies of HeGDC+B plasmas indicated a strong and favorable dependence of normalized con nement on collisionality. Discharges with lithium conditioning discussed in the present study gen- erally achieved lower collisionality, extending the accessible range of collisionality by almost an order of unity. While the confinement dependences on dimensional, engineering variables of the HeGDC+B and Li EVAP datasets differed, collisionality was found to unify the trends, with the lower collisionality lithium conditioned discharges extending the trend of increasing normalized confi nement time with decreasing collisionality when other dimension less variables were held as fi xed as possible. This increase of confi nement with decreasing collisionality was driven by a large reduction in electron transport in the outer region of the plasma. This result is consistent with gyrokinetic calculations that show microtearing and Electron Temperature Gradient modes to be more stable for the lower collisionality discharges. Ion transport, near neoclassical at high collisionality, became more anomalous at lower collisionality, possibly due to the growth of hybrid TEM/KBM modes in the outer regions of the plasma

  18. NSTX Plasma Response to Lithium Coated Divertor

    H.W. Kugel, M.G. Bell, J.P. Allain, R.E. Bell, S. Ding, S.P. Gerhardt, M.A. Jaworski, R. Kaita, J. Kallman, S.M. Kaye, B.P. LeBlanc, R. Maingi, R. Majeski, R. Maqueda, D.K. Mansfield, D. Mueller, R. Nygren, S.F. Paul, R. Raman, A.L. Roquemore, S.A. Sabbagh, H. Schneider, C.H. Skinner, V.A. Soukhanovskii, C.N. Taylor, J.R. Timberlak, W.R. Wampler, L.E. Zakharov, S.J. Zweben, and the NSTX Research Team


    NSTX experiments have explored lithium evaporated on a graphite divertor and other plasma facing components in both L- and H- mode confinement regimes heated by high-power neutral beams. Improvements in plasma performance have followed these lithium depositions, including a reduction and eventual elimination of the HeGDC time between discharges, reduced edge neutral density, reduced plasma density, particularly in the edge and the SOL, increased pedestal electron and ion temperature, improved energy confinement and the suppression of ELMs in the H-mode. However, with improvements in confinement and suppression of ELMs, there was a significant secular increase in the effective ion charge Zeff and the radiated power in H-mode plasmas as a result of increases in the carbon and medium-Z metallic impurities. Lithium itself remained at a very low level in the plasma core, <0.1%. Initial results are reported from operation with a Liquid Lithium Divertor (LLD) recently installed.

  19. On the width of a pedestal in the H-mode

    Itoh, K.; Itoh, S.-I.; Kamiya, K.; Kobayashi, T.


    The thickness of the transport barrier at the plasma edge is discussed, by analyzing the structure of the interface region between the turbulent L-mode region and the region where the transport is strongly-stabilized by the electric field. The effect of this localized radial electric field is prescribed. The spatial profile of turbulence intensity is analyzed by using a simplified model, in which the suppression and transport of turbulence intensity are introduced. The scaling property of the transport barrier is discussed.

  20. Ion cyclotron resonance heating for tungsten control in various JET H-mode scenarios

    Goniche, M.; Dumont, R. J.; Bobkov, V.; Buratti, P.; Brezinsek, S.; Challis, C.; Colas, L.; Czarnecka, A.; Drewelow, P.; Fedorczak, N.; Garcia, J.; Giroud, C.; Graham, M.; Graves, J. P.; Hobirk, J.; Jacquet, P.; Lerche, E.; Mantica, P.; Monakhov, I.; Monier-Garbet, P.; Nave, M. F. F.; Noble, C.; Nunes, I.; Pütterich, T.; Rimini, F.; Sertoli, M.; Valisa, M.; Van Eester, D.; Contributors, JET


    Ion cyclotron resonance heating (ICRH) in the hydrogen minority scheme provides central ion heating and acts favorably on the core tungsten transport. Full wave modeling shows that, at medium power level (4 MW), after collisional redistribution, the ratio of power transferred to the ions and the electrons vary little with the minority (hydrogen) concentration n H/n e but the high-Z impurity screening provided by the fast ions temperature increases with the concentration. The power radiated by tungsten in the core of the JET discharges has been analyzed on a large database covering the 2013-2014 campaign. In the baseline scenario with moderate plasma current (I p = 2.5 MA) ICRH modifies efficiently tungsten transport to avoid its accumulation in the plasma centre and, when the ICRH power is increased, the tungsten radiation peaking evolves as predicted by the neo-classical theory. At higher current (3-4 MA), tungsten accumulation can be only avoided with 5 MW of ICRH power with high gas injection rate. For discharges in the hybrid scenario, the strong initial peaking of the density leads to strong tungsten accumulation. When this initial density peaking is slightly reduced, with an ICRH power in excess of 4 MW,very low tungsten concentration in the core (˜10-5) is maintained for 3 s. MHD activity plays a key role in tungsten transport and modulation of the tungsten radiation during a sawtooth cycle is correlated to the fishbone activity triggered by the fast ion pressure gradient.

  1. Real-time control of divertor detachment in H-mode with impurity seeding using Langmuir probe feedback in JET-ITER-like wall

    Guillemaut, C.; Lennholm, M.; Harrison, J.; Carvalho, I.; Valcarcel, D.; Felton, R.; Griph, S.; Hogben, C.; Lucock, R.; Matthews, G. F.; Perez Von Thun, C.; Pitts, R. A.; Wiesen, S.; contributors, JET


    Burning plasmas with 500 MW of fusion power on ITER will rely on partially detached divertor operation to keep target heat loads at manageable levels. Such divertor regimes will be maintained by a real-time control system using the seeding of radiative impurities like nitrogen (N), neon or argon as actuator and one or more diagnostic signals as sensors. Recently, real-time control of divertor detachment has been successfully achieved in Type I ELMy H-mode JET-ITER-like wall discharges by using saturation current (I sat) measurements from divertor Langmuir probes as feedback signals to control the level of N seeding. The degree of divertor detachment is calculated in real-time by comparing the outer target peak I sat measurements to the peak I sat value at the roll-over in order to control the opening of the N injection valve. Real-time control of detachment has been achieved in both fixed and swept strike point experiments. The system has been progressively improved and can now automatically drive the divertor conditions from attached through high recycling and roll-over down to a user-defined level of detachment. Such a demonstration is a successful proof of principle in the context of future operation on ITER which will be extensively equipped with divertor target probes.

  2. Beta limits in H-modes and VH-modes in JET

    Smeulders, P.; Hender, T.C.; Huysmans, G.; Marcus, F.; Ali-Arshad, S.; Alper, B.; Balet, B.; Bures, M.; Deliyanakis, N.; Esch, H. de; Fshpool, G.; Jarvis, O.N.; Jones, T.T.C.; Ketner, W.; Koenig, R.; Lawson, K.; Lomas, P.; O`Brien, D.; Sadler, G.; Stok, D.; Stubberfield, P.; Thomas, P.; Thomen, K.; Wesson, J. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Nave, M.F. [Universidade Tecnica, Lisbon (Portugal). Inst. Superior Tecnico


    In Hot-ion H- and VH-modes, the highest achieved beta was about 10% below the Troyon value in the best case of discharge 26087. The operational space of the high beta discharges obtained before March 1992 has been explored as function of the parameters H{sub ITER89P}, {beta}{sub n}, q{sub 95}, I{sub p}. Also, a limiting envelope on the fusion reactivity as a function of the average plasma pressure and beta has been observed with R{sub DD} related to {beta}{sub {phi}}{sup 2}.B{sub {phi}}{sup 4}. MHD stability analysis shows that the JET VH modes at the edge are in the second region for ballooning mode stability. The dependence of ballooning stability and the n=1 external kink on the edge current density is analyzed. (authors). 6 figs., 6 refs.

  3. Confinement improvement in the high poloidal beta regime on DIII-D and application to steady-state H-mode on EAST

    Ding, S.; Garofalo, A. M.; Qian, J.; Cui, L.; McClenaghan, J. T.; Pan, C.; Chen, J.; Zhai, X.; McKee, G.; Ren, Q.; Gong, X.; Holcomb, C. T.; Guo, W.; Lao, L.; Ferron, J.; Hyatt, A.; Staebler, G.; Solomon, W.; Du, H.; Zang, Q.; Huang, J.; Wan, B.


    Systematic experimental and modeling investigations on DIII-D show attractive transport properties of fully non-inductive high βp plasmas. Experiments on DIII-D show that the large-radius internal transport barrier (ITB), a key feature providing excellent confinement in the high βp regime, is maintained when the scenario is extended from q95 ˜ 12 to 7 and from rapid to near-zero toroidal rotation. The robustness of confinement versus rotation was predicted by gyrofluid modeling showing dominant neoclassical ion energy transport even without the E × B shear effect. The physics mechanism of turbulence suppression, we found, is the Shafranov shift, which is essential and sets a βp threshold for large-radius ITB formation in the high βp scenario on DIII-D. This is confirmed by two different parameter-scan experiments, one for a βN scan and the other for a q95 scan. They both give the same βp threshold at 1.9 in the experiment. The experimental trend of increasing thermal transport with decreasing βp is consistent with transport modeling. The progress toward the high βp scenario on Experimental Advanced Superconducting Tokamak (EAST) is reported. The very first step of extending the high βp scenario on DIII-D to long pulse on EAST is to establish a long pulse H-mode with ITB on EAST. This paper shows the first 61 s fully non-inductive H-mode with stationary ITB feature and actively cooled ITER-like tungsten divertor in the very recent EAST experiment. The successful use of lower hybrid wave as a key tool to optimize the current profile in the EAST experiment is also introduced. Results show that as the electron density is increased, the fully non-inductive current profile broadens on EAST. The improved understanding and modeling capability are also used to develop advanced scenarios for the China Fusion Engineering Test Reactor. Overall, these results provide encouragement that the high βp regime can be extended to a lower safety factor and very low rotation

  4. Plasma Metabolic Profile Determination in Young ST-segment Elevation Myocardial Infarction Patients with Ischemia and Reperfusion: Ultra-performance Liquid Chromatography and Mass Spectrometry for Pathway Analysis

    Lei Huang; Tong Li; Ying-Wu Liu; Lei Zhang; Zhi-Huan Dong; Shu-Ye Liu; Ying-Tang Gao


    Background:This study was to establish a disease differentiation model for ST-segment elevation myocardial infarction (STEMI) youth patients experiencing ischemia and reperfusion via ultra-performance liquid chromatography and mass spectrometry (UPLC/MS) platform,which searches for closely related characteristic metabolites and metabolic pathways to evaluate their predictive value in the prognosis after discharge.Methods:Forty-seven consecutive STEMI patients (23 patients under 45 years of age,referred to here as "youth," and 24 "elderly" patients) and 48 healthy control group members (24 youth,24 elderly) were registered prospectively.The youth patients were required to provide a second blood draw during a follow-up visit one year after morbidity (n =22,one lost).Characteristic metabolites and relative metabolic pathways were screened via UPLC/MS platform base on the Kyoto encyclopedia of genes and genomes (KEGG) and Human Metabolome Database.Receiver operating characteristic (ROC) curves were drawn to evaluate the predictive value of characteristic metabolites in the prognosis after discharge.Results:We successfully established an orthogonal partial least squares discriminated analysis model (R2X =71.2%,R2Y =79.6%,and Q2 =55.9%) and screened out 24 ions; the sphingolipid metabolism pathway showed the most drastic change.The ROC curve analysis showed that ceramide [Cer(d18:0/16:0),Cer(t18:0/12:0)] and sphinganine in the sphingolipid pathway have high sensitivity and specificity on the prognosis related to major adverse cardiovascular events after youth patients were discharged.The area under curve (AUC) was 0.671,0.750,and 0.711,respectively.A follow-up validation one year after morbidity showed corresponding AUC of 0.778,0.833,and 0.806.Conclusions:By analyzing the plasma metabolism of myocardial infarction patients,we successfully established a model that can distinguish two different factors simultaneously:pathological conditions and age

  5. Influence of admission plasma glucose level on short- and long-term prognosis in patients with ST-segment elevation myocardial infarction

    Mladenović Violeta


    Full Text Available Background/Aim. Hyperglicemia is common in patients with ST-elevation myocardial infarction (STEMI and is associated with high risk of mortality and morbidity. Relationship between admission plasma glucose (APG levels and mortality in diabetic and nondiabetic patients with STEMI needs further investigation. The aim of this study was to analyse the short- and longterm prognostic significance of APG levels in patients with STEMI with and without diabetes. Methods. This study included 115 patients with STEMI, 86 (74,8% nondiabetic and 29 (25,2% dibaetic patients, in which we performed a prospective analysis of the relationship between APG levels and shortand long-term mortality. Results. Comparison of APG levels between nondiabetic (8.32 ± 2.4 mmol/L and diabetic (10.09 ± 2.5 mmol/L patients showed statistically significantly higher average APG levels in diabetic patients (p = 0.001. In all patients observed who died either after one month or one year after STEMI, average APG values were significantly higher in comparison with those in survived patients. There was no statistical significance in average APG levels in the diabetic patients with STEMI who died after one month and those who survived (10.09 ± 2.68 vs 10.0 ± 2.51 mmol/L, respectively; p = 0.657, as well as those who died after one year and those who survived (10.1 ± 1.92 vs 10.09 ± 2.8 mmol/L, respectively; p = 0.996. There was, however, statistical significance in average APG levels in the nondiabetic patients with STEMI who died after one month and those who survived (9.97 ± 2.97 vs 7.91 ± 2.08 mmol/L, respectively; p = 0.001, as well as those who died after one year and those who survived (9.17 ± 2.49 vs 7.84 ± 2.24 mmol/L, respectively; p = 0.013. Conclusion. Acute hyperglicemia in the settings of STEMI worsenes the prognosis in patients with and without diabetes. Our study showed that nondiabetic patients with high APG levels are at higher risk of mortality than patients

  6. Design of an alternating phase focusing Interdigital H-mode Drift-Tube-Linac with low injection energy

    Zhao, L.; Pang, J.; He, X.; Ying, Z.; Shi, J.


    An Inter-digital H-mode (IH) Drift Tube Linac (DTL) was designed to accelerate a proton beam in the low energy region with high RF efficiency and high gradient. The IH DTL is 1.078 m long and operates at 200 MHz. Protons could be accelerated from 0.04 MeV to 2.4 MeV (the β range is from 0.0092 to 0.0714). The method of alternating phase focusing (APF) was applied for beam focusing. The simulation results show that the transmission is 38% and the longitudinal acceptance is approximately 140°. The shunt impedance of the entire cavity is 365 MΩ/m. Adjustments of the electric-field were performed, and the beam dynamics design was described. The beam loss and voltage sensitivity were calculated.

  7. Full-f Neoclassical Simulations toward a Predictive Model for H-mode Pedestal Ion Energy, Particle and Momentum Transport

    Battaglia, D. J. [PPPL; Boedo, J. A. [University of California San Diego; Burrell, K. H. [General Atomics; Chang, C. S. [PPPL; Canik, J. M. [ORNL; deGrassie, J. S. [General Atomics; Gerhardt, S. P. [PPPL; Grierson, B. A. [General Atomics; Groebner, R. J. [General Atomics; Maingi, Rajesh [PPPL; Smith, S. P. [General Atomics


    Energy and particle transport rates are decoupled in the H-mode edge since the ion thermal transport rate is primarily set by the neoclassical transport of the deuterium ions in the tail of the thermal energy distribution, while the net particle transport rate is set by anomalous transport of the colder bulk ions. Ion orbit loss drives the energy distributions away from Maxwellian, and describes the anisotropy, poloidal asymmetry and local minimum near the separatrix observed in the Ti profile. Non-Maxwellian distributions also drive large intrinsic edge flows, and the interaction of turbulence at the top of the pedestal with the intrinsic edge flow can generate an intrinsic core torque. The primary driver of the radial electric field (Er) in the pedestal and scrapeoff layer (SOL) are kinetic neoclassical effects, such as ion orbit loss of tail ions and parallel electron loss to the divertor. This paper describes the first multi-species kinetic neoclassical transport calculations for ELM-free H-mode pedestal and scrape-off layer on DIII-D using XGC0, a 5D full-f particle-in-cell drift-kinetic solver with self-consistent neutral recycling and sheath potentials. Quantitative agreement between the flux-driven simulation and the experimental electron density, impurity density and orthogonal measurements of impurity temperature and flow profiles is achieved by adding random-walk particle diffusion to the guiding-center drift motion. This interpretative technique quantifies the role of neoclassical, anomalous and neutral transport to the overall pedestal structure, and consequently illustrates the importance of including kinetic effects self-consistently in transport calculations around transport barriers.

  8. Observation of a new turbulence-driven limit-cycle state in H-modes with lower hybrid current drive and lithium-wall conditioning in the EAST superconducting tokamak

    Wang, H.Q.; Xu, G.S.; Guo, H.Y.;


    -frequency oscillation, termed a limit-cycle state, appears at the edge during the quiescent phase with good energy and particle confinement. Detailed measurements by edge Langmuir probes show modulation interaction and strong three-wave coupling between the low-frequency oscillations and high-frequency-broadband (80......The first high confinement H-mode plasma has been obtained in the Experimental Advanced Superconducting Tokamak (EAST) with about 1 MW lower hybrid current drive after wall conditioning by lithium evaporation and real-time injection of Li powder. Following the L–H transition, a small-amplitude, low....... And the measurements demonstrate that the energy gain of zonal flows is of the same order as the energy loss of turbulence. This strongly suggests the interactions between zonal flows and high-frequency turbulences at the pedestal during the limit-cycle state....

  9. Real-time wavelet detection of crashes in limit cycles of non-stationary fusion plasmas

    van Berkel, M.; Witvoet, G.; M.R. de Baar,; Nuij, Pwjm; Morschec, H. G. ter; Steinbuch, M.


    The high performance mode (H-mode) is one of the baseline plasma scenarios for the experimental fusion reactor ITER. This scenario features a periodic crash-like reorganization of the plasma pressure and the magnetic flux in the plasma core and plasma periphery. The core instability is often referre

  10. FOREWORD: 13th International Workshop on Plasma-Facing Materials and Components for Fusion Applications/1st International Conference on Fusion Energy Materials Science 13th International Workshop on Plasma-Facing Materials and Components for Fusion Applications/1st International Conference on Fusion Energy Materials Science

    Jacob, Wolfgang; Linsmeier, Christian; Rubel, Marek


    The 13th International Workshop on Plasma-Facing Materials and Components (PFMC-13) jointly organized with the 1st International Conference on Fusion Energy Materials Science (FEMaS-1) was held in Rosenheim (Germany) on 9-13 May 2011. PFMC-13 is a successor of the International Workshop on Carbon Materials for Fusion Applications series. Between 1985 and 2003 ten 'Carbon Workshops' were organized in Jülich, Stockholm and Hohenkammer. Then it was time for a change and redefinition of the scope of the symposium to reflect the new requirements of ITER and the ongoing evolution in the field. Under the new name (PFMC-11), the workshop was first organized in 2006 in Greifswald, Germany and PFMC-12 took place in Jülich in 2009. Initially starting in 1985 with about 40 participants as a 1.5 day workshop, the event has continuously grown to about 220 participants at PFMC-12. Due to the joint organization with FEMaS-1, PFMC-13 set a new record with more than 280 participants. The European project Fusion Energy Materials Science, FEMaS, coordinated by the Max-Planck-Institut für Plasmaphysik (IPP), organizes and stimulates cooperative research activities which involve large-scale research facilities as well as other top-level materials characterization laboratories. Five different fields are addressed: benchmarking experiments for radiation damage modelling, the application of micro-mechanical characterization methods, synchrotron and neutron radiation-based techniques and advanced nanoscopic analysis based on transmission electron microscopy. All these fields need to be exploited further by the fusion materials community for timely materials solutions for a DEMO reactor. In order to integrate these materials research fields, FEMaS acted as a co-organizer for the 2011 workshop and successfully introduced a number of participants from research labs and universities into the PFMC community. Plasma-facing materials experience particularly hostile conditions as they are

  11. Towards cooperative guidance and control of highly automated vehicles: H-Mode and Conduct-by-Wire.

    Flemisch, Frank Ole; Bengler, Klaus; Bubb, Heiner; Winner, Hermann; Bruder, Ralph


    This article provides a general ergonomic framework of cooperative guidance and control for vehicles with an emphasis on the cooperation between a human and a highly automated vehicle. In the twenty-first century, mobility and automation technologies are increasingly fused. In the sky, highly automated aircraft are flying with a high safety record. On the ground, a variety of driver assistance systems are being developed, and highly automated vehicles with increasingly autonomous capabilities are becoming possible. Human-centred automation has paved the way for a better cooperation between automation and humans. How can these highly automated systems be structured so that they can be easily understood, how will they cooperate with the human? The presented research was conducted using the methods of iterative build-up and refinement of framework by triangulation, i.e. by instantiating and testing the framework with at least two derived concepts and prototypes. This article sketches a general, conceptual ergonomic framework of cooperative guidance and control of highly automated vehicles, two concepts derived from the framework, prototypes and pilot data. Cooperation is exemplified in a list of aspects and related to levels of the driving task. With the concept 'Conduct-by-Wire', cooperation happens mainly on the guidance level, where the driver can delegate manoeuvres to the automation with a specialised manoeuvre interface. With H-Mode, a haptic-multimodal interaction with highly automated vehicles based on the H(orse)-Metaphor, cooperation is mainly done on guidance and control with a haptically active interface. Cooperativeness should be a key aspect for future human-automation systems. Especially for highly automated vehicles, cooperative guidance and control is a research direction with already promising concepts and prototypes that should be further explored. The application of the presented approach is every human-machine system that moves and includes high

  12. Initial Thomson Scattering Survey of Local Helicity Injection and Ohmic Plasmas at the Pegasus Toroidal Experiment

    Schlossberg, D. J.; Bodner, G. M.; Bongard, M. W.; Fonck, R. J.; Winz, G. R.


    A multipoint Thomson scattering diagnostic has recently been installed on the Pegasus ST. The system utilizes a frequency-doubled Nd:YAG laser (λ0 ~ 532 nm), spectrometers with volume phase holographic gratings, and a gated, intensified CCD camera. It provides measurements of Te and ne at 8 spatial locations for each spectrometer once per discharge. A new multiple aperture and beam dump system has been implemented to mitigate interference from stray light. This system has provided initial measurements in the core region of plasmas initiated by local helicity injection (LHI), as well as conventional Ohmic L- and H-mode discharges. Multi-shot averages of low-density (ne ~ 3 ×1018 m-3) , Ip ~ 0 . 1 MA LHI discharges show central Te ~ 75 eV at the end of the helicity injection phase. Ip ~ 0 . 13 MA Ohmic plasmas at moderate densities (ne ~ 2 ×1019 m-3) have core Te ~ 150 eV in L-mode. Generally, these plasmas do not reach transport equilibrium in the short 25 ms pulse length available. After an L-H transition, strong spectral broadening indicates increasing Te, to values above the range of the present spectrometer system with a high-dispersion VPH grating. Near-term system upgrades will focus on deploying a second spectrometer, with a lower-dispersion grating capable of measuring the 0.1-1.0 keV range. The second spectrometer system will also increase the available number of spatial channels, enabling study of H-mode pedestal structure. Work supported by US DOE Grant DE-FG02-96ER54375.

  13. St. Lucia.


    The population of St Lucia was 123,000 in 1986, with an annual growth rate of 2%. The infant mortality rate stands at 22.2/1000 live births, and life expectancy is 70.3 years for males and 74.9 years for females. The literacy rate is 78%. St Lucia's labor force is allocated as follows: agriculture, 36.6%; industry and commerce, 20.1%; and services, 18.1%. The gross national product (GNP) was US$146 million in 1985, with an annual growth rate of 3% and a per capita GNP of $1071. St Lucia is a parliamentary democracy modeled on the British Westminster system. The island is divided into 16 parishes and 1 urban area (the capital, Castries). St Lucia is currently a politically stable country, although the high level of youth unemployment is a cause for concern. Ongoing stability may depend on the government's ability to provide services such as jobs and housing. The economy has evolved from a monocrop sugar plantation type to a diversified economy based on agriculture, industry, and tourism. Agriculture, dominated by the banana industry, is characterized by the participation of a large number of small and medium-sized enterprises. Industry is being encouraged through the provision of incentives such as tax rebates. The government is attempting to maintain a sound investment climate through a tripartite dialogue with the private sector and trade unions. Overall economic policy is predicated on the attraction of sound investments, by both local and foreign entities, to accelerate the rate of economic growth, solve the unemployment problem, and generate a solid balance-of-payments position.

  14. Temporal course of pregnancy-associated plasma protein-A in angioplasty-treated ST-elevation myocardial infarction patients and potential significance of concomitant heparin administration

    Terkelsen, Christian J; Oxvig, Claus; Nørgaard, Bjarne L


    Pregnancy-associated plasma protein-A (PAPP-A) is a putative plaque instability marker. In acute coronary syndromes, the disrupted culprit plaque contains abundant PAPP-A, and circulating PAPP-A levels predict clinical outcomes. Determinants of circulating PAPP-A levels, however, are not fully...

  15. Projection of bootstrap current in the ITER with standard type I ELMy H-mode and steady state scenarios

    Thawatchai Onjun


    Full Text Available The investigation of bootstrap current formation in ITER is carried out using BALDUR integrated predictive modelingcode. The combination of Mixed B/gB anomalous transport model and NLCASS module together with the pedestal model isused in BALDUR code to simulate the time evolution of temperature, density, and plasma current profiles. It was found inthe simulations that without the presence of ITB, a minimal fraction of bootstrap current (as well as low fusion performancewas achieved. The enhancement due to ITB depends sensitively on the strength of toroidal velocity. A sensitivity study wasalso carried out to optimize the bootstrap current fraction and plasma performance. It was found that the bootstrap currentfraction slightly improved; while the plasma performance greatly improved with increasing of NBI power or pedestal temperature.On the other hand, higher impurity concentration resulted in a significant degradation of fusion performance, buta smaller degradation in bootstrap current.

  16. Operational characteristics and non-inductive plasmas on NSTX-U

    Mueller, Dennis


    Start-up and ramp-up of NSTX-U plasmas with nearly full solenoid pre-charge required higher loop voltage than on NSTX in agreement with modeling. NSTX-U has operated with a plasma current (Ip) of 0.65 MA at a toroidal field (BT) of 0.63 T for 2s in L-Mode. These plasmas allowed for the initial investigation of error field correction which found a difference between correction during Ip flattop and during ramp-up. Plasma control using feedback on the X-Point locations or the X-point height and outer strike point locations is routinely used. Because an ST does not have a single coil set that controls the inner gap, it was challenging to control the time at which the plasma diverted. A novel approach was used to trade off accuracy on the outer plasma shape to achieve a reproducible inner gap. These control tools allowed study of ELMy H-mode operation at Ip = 1 MA with boronized walls. A major long-term goal for NSTX-U is totally non-inductive operation. The plan calls for initiating the plasma with coaxial helicity injection (CHI) heatied by ECH, then current drive and heating by HHFW and NBI. CHI will be used in the new geometry to demonstrate results comparable to NSTX and provide information to inform plans to upgrade the available voltage from 1.65 to 2 kV next year. Low Ip plasmas will be used to study the dependence of current drive on neutral beam voltage and injection angle. Work Supported by U.S.D.O.E. Contract No. DE-AC02-09CH11466.

  17. Measurements of the edge current evolution and comparison with neoclassical calculations during MAST H-modes using motional Stark effect

    de Bock, M. F. M.; Citrin, J.; Saarelma, S.; Temple, D.; Conway, N. J.; Kirk, A.; Meyer, H.; Michael, C. A.


    Edge localized modes (ELMs), that are present in most tokamak H-(high confinement) modes, can cause significant damage to plasma facing components in fusion reactors. Controlling ELMs is considered necessary and hence it is vital to understand the underlying physics. The stability of ELMs is typical

  18. Measurements of the edge current evolution and comparison with neoclassical calculations during MAST H-modes using motional Stark effect

    de Bock, M. F. M.; Citrin, J.; Saarelma, S.; Temple, D.; Conway, N. J.; Kirk, A.; Meyer, H.; Michael, C. A.


    Edge localized modes (ELMs), that are present in most tokamak H-(high confinement) modes, can cause significant damage to plasma facing components in fusion reactors. Controlling ELMs is considered necessary and hence it is vital to understand the underlying physics. The stability of ELMs is

  19. Contrasting H-mode behaviour with deuterium fuelling and nitrogen seeding in the all-carbon and metallic versions of JET

    Maddison, G P; Alper, B; Arnoux, G; Balboa, I; Beurskens, M N A; Boboc, A; Brezinsek, S; Brix, M; Clever, M; Coelho, R; Coenen, J W; Coffey, I; Belo, P C da Silva Aresta; Devaux, S; Devynck, P; Eich, T; Felton, R C; Flanagan, J; Frassinetti, L; Garzotti, L; Groth, M; Jachmich, S; Järvinen, A; Joffrin, E; Kempenaars, M A H; Kruezi, U; Lawson, K D; Lehnen, M; Leyland, M J; Liu, Y; Lomas, P J; Lowry, C G; Marsen, S; Matthews, G F; McCormick, G K; Meigs, A G; Morris, A W; Neu, R; Nunes, I M; Oberkofler, M; Rimini, F G; Saarelma, S; Sieglin, B; Sips, A C C; Sirinelli, A; Stamp, M F; van Rooij, G J; Ward, D J; Wischmeier, M; contributors, JET EFDA


    The former all-carbon wall on JET has been replaced with beryllium in the main torus and tungsten in the divertor to mimic the surface materials envisaged for ITER. Comparisons are presented between Type I H-mode characteristics in each design by examining respective scans over deuterium fuelling and impurity seeding, required to ameliorate exhaust loads both in JET at full capability and in ITER.

  20. Dependence of recycling and edge profiles on lithium evaporation in high triangularity, high performance NSTX H-mode discharges

    Maingi, R., E-mail: [Princeton Plasma Physics Laboratory, Receiving 3, Route 1 North, Princeton, NJ 08543 (United States); Osborne, T.H. [General Atomics, 3550 General Atomics Ct., San Diego, CA 92121 (United States); Bell, M.G.; Bell, R.E.; Boyle, D.P. [Princeton Plasma Physics Laboratory, Receiving 3, Route 1 North, Princeton, NJ 08543 (United States); Canik, J.M. [Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831 (United States); Diallo, A.; Kaita, R.; Kaye, S.M.; Kugel, H.W.; LeBlanc, B.P. [Princeton Plasma Physics Laboratory, Receiving 3, Route 1 North, Princeton, NJ 08543 (United States); Sabbagh, S.A. [Applied Physics and Applied Math Dept., Columbia University, New York, NY 10027 (United States); Skinner, C.H. [Princeton Plasma Physics Laboratory, Receiving 3, Route 1 North, Princeton, NJ 08543 (United States); Soukhanovskii, V.A. [Lawrence Livermore National Laboratory, 7000 East Ave, PO Box 808, Livermore, CA 94551 (United States)


    In this paper, the effects of a pre-discharge lithium evaporation variation on highly shaped discharges in the National Spherical Torus Experiment (NSTX) are documented. Lithium wall conditioning (‘dose’) was routinely applied onto graphite plasma facing components between discharges in NSTX, partly to reduce recycling. Reduced D{sub α} emission from the lower and upper divertor and center stack was observed, as well as reduced midplane neutral pressure; the magnitude of reduction increased with the pre-discharge lithium dose. Improved energy confinement, both raw τ{sub E} and H-factor normalized to scalings, with increasing lithium dose was also observed. At the highest doses, we also observed elimination of edge-localized modes. The midplane edge plasma profiles were dramatically altered, comparable to lithium dose scans at lower shaping, where the strike point was farther from the lithium deposition centroid. This indicates that the benefits of lithium conditioning should apply to the highly shaped plasmas planned in NSTX-U.

  1. The effect of induction of CYP3A4 by St John's wort on ambrisentan plasma pharmacokinetics in volunteers of known CYP2C19 genotype.

    Markert, Christoph; Kastner, Ida Maria; Hellwig, Regina; Kalafut, Peter; Schweizer, Yvonne; Hoffmann, Michael Marcus; Burhenne, Jürgen; Weiss, Johanna; Mikus, Gerd; Haefeli, Walter Emil


    To evaluate the impact of CYP2C19 polymorphisms on ambrisentan exposure and to assess its modification by St. John's wort (SJW), 20 healthy volunteers (10 CYP2C19 extensive, four poor and six ultrarapid metabolizers) received therapeutic doses of ambrisentan (5 mg qd po) for 20 days and concomitantly SJW (300 mg tid po) for the last 10 days. To quantify changes of CYP3A4 activity, midazolam (3 mg po) as a probe drug was used. Ambrisentan pharmacokinetics was assessed on days 1, 10 and 20, and midazolam pharmacokinetics before and on days 1, 10, 17 and 20. At steady state, ambrisentan exposure was similar in extensive and ultrarapid metabolizers but 43% larger in poor metabolizers (p < 0.01). In all volunteers, SJW reduced ambrisentan exposure and the relative change (17-26%) was similar in all genotype groups. The extent of this interaction did not correlate with the changes in CYP3A activity (midazolam clearance) (rs = 0.23, p = 0.34). Ambrisentan had no effect on midazolam pharmacokinetics. In conclusion, SJW significantly reduced exposure with ambrisentan irrespective of the CYP2C19 genotype. The extent of this interaction was small and thus likely without clinical relevance.

  2. Microwave Argon Plasma Torch


    an electron-ion pair in the discharge. Fig. 2. EEDF is non - Maxwellian and changes along the plasma column The electron–neutral collision...plasma radius. Even at atmospheric pressure the EEDF is non - Maxwellian and it is changing along the plasma column. ...18 31st ICPIG, July 14-19, 2013, Granada, Spain EEDF usually strongly differs from Maxwellian and chages along the plasma column (this is

  3. Decrease in Plasma Cyclophilin A Concentration at 1 Month after Myocardial Infarction Predicts Better Left Ventricular Performance and Synchronicity at 6 Months: A Pilot Study in Patients with ST Elevation Myocardial Infarction

    Huang, Ching-Hui; Chang, Chia-Chu; Kuo, Chen-Ling; Huang, Ching-Shan; Lin, Chih-Sheng; Liu, Chin-San


    Background: Cyclophilin A (CyPA) concentration increases in acute coronary syndrome. In an animal model of acute myocardial infarction, administration of angiotensin-converting-enzyme inhibitor was associated with lower left ventricular (LV) CyPA concentration and improved LV performance. This study investigated the relationships between changes in plasma CyPA concentrations and LV remodeling in patients with ST-elevation myocardial infarction (STEMI). Methods and Results: We enrolled 55 patients who underwent percutaneous coronary intervention for acute STEMI. Plasma CyPA, matrix metalloproteinase (MMP), interleukin-6 and high-sensitivity C-reactive protein concentrations were measured at baseline and at one-month follow-up. Echocardiography was performed at baseline and at one-, three-, and six-month follow-up. Patients with a decrease in baseline CyPA concentration at one-month follow-up (n = 28) had a significant increase in LV ejection fraction (LVEF) (from 60.2 ± 11.5% to 64.6 ± 9.9%, p decrease in CyPA concentration at one month (n = 27) did not show improvement in LVEF and had a significantly increased systolic dyssynchrony index (SDI) (from 1.170 ± 0.510% to 1.637 ± 1.299%, p = 0.042) at six months. Multiple linear regression analysis showed a significant association between one-month CyPA concentration and six-month LVEF. The one-month MMP-2 concentration was positively correlated with one-month CyPA concentration and LV SDI. Conclusions: Decreased CyPA concentration at one-month follow-up after STEMI was associated with better LVEF and SDI at six months. Changes in CyPA, therefore, may be a prognosticator of patient outcome. PMID:25552928

  4. Varying the Pre-discharge Lithium Wall Coatings to Alter the Characteristics of the ELM-free H-mode Pedestal in NSTX

    D.P. Boyle, J.M. Canik, R. Maing, P.B. Snyder, T.H. Osborne, and the NSTX Team


    A previous experiment in the National Spherical Torus Experiment (NSTX) showed pre-discharge lithium deposition gradually suppresed edge-localized modes (ELMs) and had nearly continuous relationships with reduced recycling and transport. In this paper, additional data filled gaps in the earlier experiment, and demonstrates that recycling, confinement, and pedestal structure continued to improve with additional lithium, even after ELMs were completely suppressed. New analysis shows that toroidal rotation and ion temperature also increased continuously with additional lithium. Besides its evolution with additional lithium, we also characterize the time evolution of the ELM-free H-mode pedestal as average density rose and impurities accumulated. We find that the pedestal structure, divertor heat flux and Dalpha profiles, and inferred recycling coefficient did not change significantly, at least until radiative losses become dominant. This suggests that the low-recycling properties of lithium were not significantly degraded over the duration of the discharge.

  5. St. John's Wort (image)

    The herb St. John's Wort is believed to be helpful in relieving mild to moderate depression, but should only be taken under a physician's supervision. St. John's Wort may clash with other medications or foods a ...

  6. Roegneria alashanica Keng: a species with the StStSt(Y)St(Y) genome constitution.

    Wang, Richard R-C; Jensen, Kevin B


    The genome constitution of tetraploid Roegneria alashanica Keng has been in question for a long time. Most scientific studies have suggested that R. alashanica had two versions of the St genome, St1St2, similar to that of Pseudoroegneria elytrigioides (C. Yen & J.L. Yang) B.R. Lu. A study, however, concluded that R. alashanica had the StY genome formula typical for tetraploid species of Roegneria. For the present study, R. alashanica, Elymus longearistatus (Bioss.) Tzvelev (StY genomes), Pseudoroegneria strigosa (M. Bieb.) Á. Löve (St), Pseudoroegneria libanoctica (Hackel) D.R. Dewey (St), and Pseudoroegneria spicata (Pursh) Á. Löve (St) were screened for the Y-genome specific marker B14(F+R)269. All E. longearistatus plants expressed intense bands specific to the Y genome. Only 6 of 10 R. alashanica plants exhibited relatively faint bands for the STS marker. Previously, the genome in species of Pseudoroegneria exhibiting such faint Y-genome specific marker was designated as St(Y). Based on these results, R. alashanica lacks the Y genome in E. longearistatus but likely possess two remotely related St genomes, St and St(Y). According to its genome constitution, R. alashanica should be classified in the genus Pseudoroenera and given the new name Pseudoroegneria alashanica (Keng) R.R.-C. Wang and K.B. Jensen.

  7. Rapid Hydrophilization of Model Polyurethane/Urea (PURPEG) Polymer Scaffolds Using Oxygen Plasma Treatment

    Rok Zaplotnik; Alenka Vesel; Gregor Primc; Xiangyu Liu; Chen, Kevin C; Chiju Wei; Kaitian Xu; Miran Mozetic


    Polyurethane/urea copolymers based on poly(ethylene glycol) (PURPEG) were exposed to weakly ionized, highly reactive low-pressure oxygen plasma to improve their sorption kinetics. The plasma was sustained with an inductively coupled radiofrequency generator operating at various power levels in either E-mode (up to the forward power of 300 W) or H-mode (above 500 W). The treatments that used H-mode caused nearly instant thermal degradation of the polymer samples. The density of the charged par...

  8. Plasma physics for controlled fusion

    Miyamoto, Kenro


    This new edition presents the essential theoretical and analytical methods needed to understand the recent fusion research of tokamak and alternate approaches. The author describes magnetohydrodynamic and kinetic theories of cold and hot plasmas in detail. The book covers new important topics for fusion studies such as plasma transport by drift turbulence, which depend on the magnetic configuration and zonal flows. These are universal phenomena of microturbulence. They can modify the onset criterion for turbulent transport, instabilities driven by energetic particles as well as alpha particle generation and typical plasma models for computer simulation. The fusion research of tokamaks with various new versions of H modes are explained. The design concept of ITER, the international tokamak experimental reactor, is described for inductively driven operations as well as steady-state operations using non-inductive drives. Alternative approaches of reversed-field pinch and its relaxation process, stellator includi...

  9. Tungsten divertor sourcing in DIII-D H-mode discharges and its impact on core impurity accumulation in different ELM regimes

    Abrams, T.; Ding, R.; Guterl, J.; Briesemeister, A.; Unterberg, E. A.; Guo, H. Y.; Leonard, A. W.; Thomas, D. M.; McLean, A. G.; Victor, B.; Rudakov, D.; Grierson, B.; Watkins, J. G.; Elder, J. D.; Stangeby, P. C.


    Significant progress has been made understanding W sourcing during Type I ELMy H-mode on DIII-D using fast high-resolution measurements of W sourcing coupled with OEDGE/ERO and TRIM.SP modeling. ERO modeling of the inter-ELM phase, using a new OEDGE capability for charge state-resolved carbon ion fluxes and a material mixing model, shows measured W erosion is well explained by C- >W sputtering. Ion impact energies in the DIII-D divertor during ELMs, inferred from ratios of heat flux to ion flux, are 200-500 eV. Comparisons with TRIM.SP indicate C- >W sputtering dominates W sourcing during ELMs. This is in contrast to JET where ion impact energies are 3-5 keV during ELMs, predicted by the ``free streaming model,'' and D- >W sputtering strongly contributes to W sourcing. Fast measurements of W erosion dynamics during ELMs agree well with TRIM.SP-based sputtering models assuming C/W surface concentrations of 0.5-0.8 and a 2% C2+ ion flux fraction. Core W accumulation and SOL W density measurements made during the DIII-D high-Z tile array mini-campaign correlate with ELM frequency and W source rate. Supported by US DOE under DE-FC02-04ER54698.

  10. A statistical methodology to derive the scaling law for the H-mode power threshold using a large multi-machine database

    Murari, A.; Lupelli, I.; Gaudio, P.; Gelfusa, M.; Vega, J.


    In this paper, a refined set of statistical techniques is developed and then applied to the problem of deriving the scaling law for the threshold power to access the H-mode of confinement in tokamaks. This statistical methodology is applied to the 2010 version of the ITPA International Global Threshold Data Base v6b(IGDBTHv6b). To increase the engineering and operative relevance of the results, only macroscopic physical quantities, measured in the vast majority of experiments, have been considered as candidate variables in the models. Different principled methods, such as agglomerative hierarchical variables clustering, without assumption about the functional form of the scaling, and nonlinear regression, are implemented to select the best subset of candidate independent variables and to improve the regression model accuracy. Two independent model selection criteria, based on the classical (Akaike information criterion) and Bayesian formalism (Bayesian information criterion), are then used to identify the most efficient scaling law from candidate models. The results derived from the full multi-machine database confirm the results of previous analysis but emphasize the importance of shaping quantities, elongation and triangularity. On the other hand, the scaling laws for the different machines and at different currents are different from each other at the level of confidence well above 95%, suggesting caution in the use of the global scaling laws for both interpretation and extrapolation purposes.

  11. Intra-ELM phase modelling of a JET ITER-like wall H-mode discharge with EDGE2D-EIRENE

    Harting, D.M., E-mail: [CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Wiesen, S. [Institute of Energy and Climate Research – IEK4, Association EURATOM-FZJ, D-52425 Jülich (Germany); Groth, M. [Aalto University, Association EURATOM-Tekes, Espoo (Finland); Brezinsek, S. [Institute of Energy and Climate Research – IEK4, Association EURATOM-FZJ, D-52425 Jülich (Germany); Corrigan, G.; Arnoux, G. [CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Boerner, P. [Institute of Energy and Climate Research – IEK4, Association EURATOM-FZJ, D-52425 Jülich (Germany); Devaux, S.; Flanagan, J. [CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Järvinen, A. [Aalto University, Association EURATOM-Tekes, Espoo (Finland); Marsen, S. [Max-Planck-Institut für Plasmaphysik, EURATOM-Association, D-17491 Greifswald (Germany); Reiter, D. [Institute of Energy and Climate Research – IEK4, Association EURATOM-FZJ, D-52425 Jülich (Germany)


    We present the application of an improved EDGE2D-EIRENE SOL transport model for the ELM phase utilizing kinetic correction of the sheath-heat-transmission coefficients and heat-flux-limiting factors used in fluid SOL modelling. With a statistical analysis over a range of similar type-I ELMy H-mode discharges performed at the end of the first JET ITER-like wall campaign, we achieved a fast (Δt = 200 μs) temporal evolution of the outer midplane n{sub e} and T{sub e} profiles and the target-heat and particle-flux profiles, which provides a good experimental data set to understand the characteristics of an ELM cycle. We will demonstrate that these kinetic corrections increase the simulated heat-flux-rise time at the target to experimentally observed times but the power-decay time at the target is still underestimated by the simulations. This longer decay times are potentially related to a change of the local recycling coefficient at the tungsten target plate directly after the heat pulse.

  12. Surveys in 1961 on St. Thomas & St. Croix

    Dahl, Thorkel; Licht, Kjeld de Fine


    Registration of towns and buildings erected during the Danish reign of the Caribbean Isles of St. Thomas, St. Jan and St. Croix 1671-1917 (now belonging to the USA under the name of Virgin Islands).......Registration of towns and buildings erected during the Danish reign of the Caribbean Isles of St. Thomas, St. Jan and St. Croix 1671-1917 (now belonging to the USA under the name of Virgin Islands)....

  13. The Effect of Plasma Beta on High-n Ballooning Stability at Low Magnetic Shear

    Connor, J W; Hastie, R J


    An explanation of the observed improvement in H-mode pedestal characteristics with increasing core plasma pressure or poloidal beta, as observed in MAST and JET, is sought in terms of the impact of the Shafranov shift, d', on ideal ballooning MHD stability.

  14. Low- and high-mode separation of short wavelength turbulence in dithering Wendelstein 7-AS plasmas

    Basse, N.P.; Zoletnik, S.; Saffman, M.;


    In this article measurements of small scale electron density fluctuations in dithering high confinement (H)-mode plasmas obtained by collective scattering of infrared light are presented. A scan of the fluctuation wavenumber was made in a series of similar discharges in the Wendelstein 7-AS (W7-AS...

  15. Effect of impurities on the transition between minority ion and mode conversion ICRH heating in (3He)-H tokamak plasmas


    Hydrogen majority plasmas will be used in the initial non-activated phase of ITER operation. Optimizing ion cyclotron resonance heating (ICRH) in such scenarios will help in achieving H-mode in these plasmas. Past JET experiments with the carbon wall revealed a significant impact of intrinsic impurities on the ICRH performance in (3He)-H plasmas relevant for the full-field initial ITER phase. High plasma contamination with carbon impurities resulted in the appearance of a supplementary mode c...

  16. 可溶性ST2在射血分数保留的心力衰竭患者中的表达及其预后价值%Plasma soluble ST2 level and prognostic value in patients with heart failure with preserved ejection fraction


    目的:比较射血分数保留的心力衰竭(HFPEF)患者和射血分数下降的心力衰竭(HFREF)患者治疗过程中血浆可溶性ST2(sST2)及氨基末端脑钠肽前体(NT-proBNP)的水平和早期变化,并探讨其对心血管事件的预测价值.方法:将61例急性失代偿性心衰患者按照左室射血分数(LVEF)分为HFPEF组(35例)及HFREF组(26例).比较两组入院时、入院第7天sST2及NT-proBNP的水平,随访并记录患者入院后6个月心血管事件(全因死亡、心衰再住院)的发生情况.结果:HFREF组患者入院时、入院第7天sST2、NT-proBNP水平高于HFPEF组(均P<0.05).两组入院第7天NT-proBNP水平较入院时明显下降,而sST2在治疗过程中变化不明显.经Logsitic回归分析发现(纳入因素包括NT-proBNP),入院时sST2水平是上述两种心衰患者发生心血管事件的独立危险因素(HFPEF组:OR:1.411,95%CI:1.038~1.918,P<0.05;HFREF组:OR:1.033,95%CI:1.009~1.058,P<0.001).通过ROC曲线发现,只有NT-proBNP的变化值具有预测心血管事件的价值(ROC曲线下面积为0.753,界值为2 852 pg/ml,灵敏度92.3%,特异度56.2%,P=0.005).而治疗过程中sST2水平的短期变化值无预测心血管事件的价值.结论:HFPEF患者血浆sST2水平显著低于HFREF患者.入院时sST2水平是急性心衰患者发生心血管事件的独立危险因素,与LVEF无关.NT-proBNP水平的短期变化具有预测心血管事件的价值.

  17. St. Croix trap study

    National Oceanic and Atmospheric Administration, Department of Commerce — The data set contains detailed information about the catch from 600 trap stations around St. Croix. Data fields include species caught, size data, trap location...

  18. DIII-D Edge Plasma, Disruptions, and Radiative Processes. Final Report

    Boedo, J. A.; Luckhardt, S.C.; Moyer, R. A.


    The scientific goal of the UCSD-DIII-D Collaboration during this period was to understand the coupling of the core plasma to the plasma-facing components through the plasma boundary (edge and scrape-off layer). To achieve this goal, UCSD scientists studied the transport of particles, momentum, energy, and radiation from the plasma core to the plasma-facing components under normal (e.g., L-mode, H-mode, and ELMs), and off-normal (e.g., disruptions) operating conditions.

  19. The changes of inflammatory cytokines and their clinical significance in patients of inferior ST-segment elevation acute myocardial infarction with anterior ST-segment depression



    Objective To investigate the level of Hs-CRP,Fib,IL-6,TNF-α,MDA,SOD,and analyze the correlation between the level of plasma inflammatory cytokines and clinical significance in patients with anterior ST-segment depression.Methods We chose 360 patients with inferior ST Segment elavation acute myocardial infarction from May 2007 to Sep 2012 in emergency department of

  20. Predicting high harmonic ion cyclotron heating efficiency in Tokamak plasmas

    Green, David L [ORNL; Jaeger, E. F. [XCEL; Berry, Lee A [ORNL; Chen, Guangye [ORNL; Ryan, Philip Michael [ORNL; Canik, John [ORNL


    Observations of improved radio frequency (RF) heating efficiency in high-confinement (H-) mode plasmas on the National Spherical Tokamak Experiment (NSTX) are investigated by whole-device linear simulation. We present the first full-wave simulation to couple kinetic physics of the well confined core plasma to the poorly confined scrape-off plasma. The new simulation is used to scan the launched fast-wave spectrum and examine the steady-state electric wave field structure for experimental scenarios corresponding to both reduced, and improved RF heating efficiency. We find that launching toroidal wave-numbers that required for fast-wave propagation excites large amplitude (kVm 1 ) coaxial standing modes in the wave electric field between the confined plasma density pedestal and conducting vessel wall. Qualitative comparison with measurements of the stored plasma energy suggest these modes are a probable cause of degraded heating efficiency. Also, the H-mode density pedestal and fast-wave cutoff within the confined plasma allow for the excitation of whispering gallery type eigenmodes localised to the plasma edge.

  1. Plasma physics for controlled fusion. 2. ed.

    Miyamoto, Kenro


    This new edition presents the essential theoretical and analytical methods needed to understand the recent fusion research of tokamak and alternate approaches. The author describes magnetohydrodynamic and kinetic theories of cold and hot plasmas in detail. The book covers new important topics for fusion studies such as plasma transport by drift turbulence, which depend on the magnetic configuration and zonal flows. These are universal phenomena of microturbulence. They can modify the onset criterion for turbulent transport, instabilities driven by energetic particles as well as alpha particle generation and typical plasma models for computer simulation. The fusion research of tokamaks with various new versions of H modes are explained. The design concept of ITER, the international tokamak experimental reactor, is described for inductively driven operations as well as steady-state operations using non-inductive drives. Alternative approaches of reversed-field pinch and its relaxation process, stellator including quasi-symmetric system, open-end system of tandem mirror and inertial confinement are also explained. Newly added and updated topics in this second edition include zonal flows, various versions of H modes, and steady-state operations of tokamak, the design concept of ITER, the relaxation process of RFP, quasi-symmetric stellator, and tandem mirror. The book addresses graduate students and researchers in the field of controlled fusion.

  2. St. Vincent Island Tour

    US Fish and Wildlife Service, Department of the Interior — This letter, written by Charles Marks who lived on St. Vincent Island as a child, notes the changes he saw in the island when he visited in 1981. He notes that the...

  3. Nonlinear electromagnetic fields in 0.5 MHz inductively coupled plasmas

    Ostrikov, K.N.; Tsakadze, E.L.; Xu, S.


    Radial profiles of magnetic fields in the electrostatic (E) and electromagnetic (H) modes of low-frequency (similar to500 kHz) inductively coupled plasmas have been measured using miniature magnetic probes. In the low-power (similar to170 W) E-mode, the magnetic field pattern is purely linear......, with the fundamental frequency harmonics only. After transition to higher-power (similar to1130 W) H-mode, the second-harmonic nonlinear azimuthal magnetic field B-phi(2omega) that is in 4-6 times larger than the fundamental frequency component B-phi(omega), has been observed. A simplified plasma fluid model...... explaining the generation of the second harmonics of the azimuthal magnetic field in the plasma source is proposed. The nonlinear second harmonic poloidal (r-z) rf current generating the azimuthal magnetic field B-phi(2omega) is attributed to nonlinear interactions between the fundamental frequency radial...

  4. ST-elevations-myokardieinfarkt efter terapeutisk adrenalininjektion

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


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

  5. Confinement improvement in the high poloidal beta regime on DIII-D and application to steady-state H-mode on EAST

    Ding, S.


    Systematic experimental and modeling investigations on DIII-D and EAST show attractive transport properties of fully non-inductive high βP plasmas. The improved understanding is used to develop steady state scenarios for ITER and CFETR. Experiments on DIII-D show that the large-radius internal transport barrier (ITB), a key feature providing improved performance in the high βP regime, is maintained when the scenario is extended from q95 10 to 7 and from rapid to near-zero plasma rotation. The robustness of confinement versus rotation was predicted by gyrofluid modeling showing dominant neoclassical ion energy transport even without E ×B shear effect on turbulence suppression. Measured electron turbulent transport is large when ion turbulent transport is low, consistent with recent multi-scale simulations. With decreasing q95, dominant turbulent transport shifts from electrons to ions, which exceeds the neoclassical ion transport level, and may set a q95 limit for the large-radius ITB regime. Experiments also show that the ITB is lost below βN 1.5 , when long wavelength turbulence increases in agreement with predictions of turbulence suppression by Shafranov shift. In DIII-D, a broad current profile enabling large radius ITB is accessed via early heating and sustained with high bootstrap current fraction. Experiments on EAST show that a broad current profile can be accessed and sustained exploiting a large fraction of lower hybrid wave current drive (LHCD). Results show that as the electron density is increased, the fully non-inductive current profile broadens on EAST. Overall, these results provide encouragement that high performance high βP regimes can be extended to lower safety factor and very low rotation, providing potential paths to steady state in ITER and CFETR. Supported in part by the US DOE under DE-FC02-04ER54698 and the NNSF of China under 11575248.

  6. Identification of plasma-edge-related operational regime boundaries and the effect of edge instability on confinement in ASDEX Upgrade

    Suttrop, W.; Kaufmann, M.; Blank, H.J. de; Bruesehaber, B.; Lackner, K.; Mertens, V.; Murmann, H.; Neuhauser, J.; Ryter, F.; Salzmann, H.; Schweinzer, J.; Stober, J. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstrasse 2, D-85748 Garching (Germany); Zohm, H. [Institut fuer Plasmaforschung, Universitaet Stuttgart, Pfaffenwaldring 31, D-70569 Stuttgart (Germany)


    Local edge parameters on the ASDEX Upgrade tokamak are investigated at the L-mode to H-mode transition, during phases with various types of edge-localized modes (ELMs), and at the density limit. A scaling law for the boundary electron temperature, T{sub e,b}{sup thresh} {proportional_to} n{sub e,b}{sup -0.3}B{sub t}{sup 0.8}I{sub p}{sup 0.5}, is found which describes the H-mode threshold for deuterium-puffed discharges with favourable ion {nabla}B-drift direction. The region of stable operation is bounded by type I ELMs near the ideal ballooning limit and by a minimum temperature necessary to avoid thermal instability of the plasma edge. Stationary operation with type III ELMs imposes an upper limit on the edge temperature. Within the entire range of boundary densities investigated (n{sub e,b}{<=}8x10{sup 19}m{sup -3}), both L-mode and H-mode are found to be accessible. During type I ELMy H-mode, a relation of global confinement with the edge pressure gradient is found which is connected with a loss of the favourable density dependence predicted by the ITER-92P and ITER-93H ELMy H-mode scalings. At high density, better confinement is achieved in H-modes with an edge pressure gradient below the ideal ballooning limit, e.g. during type III ELMy H-mode with impurity-seeded radiation. (author)

  7. Concentração plasmática de progesterona em novilhas receptoras submetidas à administração de rbST, GnRH ou hCG no quinto dia do ciclo estral Plasma progesterone concentration in recipient heifers submitted to administration of rbST, GnRH or hCG on day five of the estrous cycle

    J.F. Fonseca


    Full Text Available Avaliaram-se a habilidade de diferentes hormônios administrados no quinto dia do ciclo estral em induzir a ovulação do folículo dominante da primeira onda folicular (FDPO e formar um corpo lúteo acessório (CLa e seus efeitos sobre a concentração plasmática de progesterona (P4 em novilhas receptoras. Cinqüenta e duas novilhas mestiças Holandês-Zebu foram aleatoriamente distribuídas em quatro tratamentos: T1-controle, T2-administração subcutânea de 500mg de rbST, T3-administração intramuscular (IM de 100mig de GnRH e T4-administração IM de 2000UI e endovenosa de 1000UI de hCG. Realizou-se palpação transretal nos dias 5, 13 e 60 para detecção de corpo lúteo original (CLo, de CLa e de gestação, respectivamente. A formação de CLa foi de: T1-0/12 (0,0%, T2-0/13 (0,0%, T3-5/12 (41,7% e T4-10/15 (66,7%(P0,05. As taxas de gestação, T1=37,5% (3/8, T2=62,5% (5/8, T3=28,6% (2/7 e T4=33,3% (3/9, não diferiram entre tratamentos (P>0,05. Estes resultados mostraram que o FDPO no quinto dia do ciclo estral foi capaz de responder ao GnRH e à hCG, ovular e formar um CLa, o que elevou a concentração plasmática de P4 de novilhas no 13º dia do ciclo estral, período crítico para o estabelecimento da gestação em bovinos.The ability of different hormones administered on day five of the estrous cycle to induce the ovulation of the first wave dominant follicle (FWDF and to form an accessory corpus luteum (CLa, and the respective effects on plasma progesterone concentrations were studied in recipient heifers. Fifty-two crossbred Holstein-Zebu heifers were randomly assigned to four treatments: T1-control, T2-subcutaneous administration of 500mg of rbST, T3-intramuscular administration of 100mug of GnRH and T4-administration of 3000IU of hCG (1000IU endovenous and 2000IU intramuscular. Transrectal palpation was performed on days 5, 13 and 60 to check original corpus luteum, CLa and pregnancy, respectively. CLa formation was as follow

  8. Characterization of St and Y genome in StStYY Elymus species (Triticeae: Poaceae) using Sequential FISH and GISH

    Tetraploid species possessing StY genome could be donors to hexaploid species having StYH, StYP, or StYW genome constitution in the genus Elymus, and a few of StY species have been intensely studied for inferring the origin of the Y genome. In this study, genome characterization of St and Y genome w...

  9. The St. Louis Motor

    Greenslade, Thomas B.


    The St. Louis Motor, invented in 1909, is unique among physics apparatus for being named for a geographical place rather than a physicist. The sturdy little device (Fig. 1) has never been out of production. Any older school or physics department that has not done a catastrophic housecleaning in the last 20 years will certainly have a small flock of them in the back room.

  10. Glueballs amass at RHIC and LHC Colliders! - The early quarkless 1st order phase transition at $T=270$ MeV - from pure Yang-Mills glue plasma to GlueBall-Hagedorn states

    Stoecker, Horst; Schramm, Stefan; Senzel, Florian; Greiner, Carsten; Beitel, Maxim; Gallmeister, Kai; Gorenstein, Mark; Mishustin, Igor; Vasak, David; Steinheimer, Jan; Struckmeier, Juergen; Vovchenko, Volodymyr; Satarov, Leonid; Xu, Zhe; Zhuang, Pengfei; Csernai, Laszlo P; Sinha, Bikash; Raha, Sibaji; Biró, Tamás Sándor; Panero, Marco


    The early stage of high multiplicity pp, pA and AA collider is represented by a nearly quarkless, hot, deconfined pure gluon plasma. According to pure Yang-Mills Lattice Gauge Theory, this hot pure glue matter undergoes, at a high temperature, $T_c = 270$ MeV, a first order phase transition into a confined Hagedorn-GlueBall fluid. These new scenario should be characterized by a suppression of high $p_T$ photons and dileptons, baryon suppression and enhanced strange meson production. We propose to observe this newly predicted class of events at LHC and RHIC.

  11. Communication from ST Group

    TS Department


    In order to prepare the organization of the Open Days, please note that FM Group will not able to take into account either specific requests for waste collection from 2nd to 6th of April, either removal or PC transport requests between the 31st and the 11th of March. We kindly ask you to plan the collection of any type of waste and the urgent transport of office furniture or PC before the 31st of March. Waste collection requests shall be formulated contacting FM Support at 77777 or at the email address; removal of office furniture or PC transport requests must be made using the EDH ‘Transport request’ form selecting the "Removals" or the "PC transport" category from the drop-down menu. For any question concerning the waste sorting, please consult the following web address: Thank you for your understanding and collaboration. TS/FM Group

  12. Communication from ST Group

    TS Department


    In order to prepare the organization of the Open Days, please note that FM Group will not able to take into account either specific requests for waste collection from 2nd to 6th of April, either removal or PC transport requests between the 31st and the 11th of March. We kindly ask you to plan the collection of any type of waste and the urgent transport of office furniture or PC before the 31st of March. Waste collection requests shall be formulated contacting FM Support at 77777 or at the email address; removal of office furniture or PC transport requests must be made using the EDH ‘Transport request’ form selecting the "Removals" or the "PC transport" category from the drop-down menu. For any question concerning the waste sorting, please consult the following web address: Thank you for your understanding and collaboration. TS/FM Group

  13. St. Thomas Aquinas, Dramatist?

    Eric McLuhan


    Full Text Available The article begins with the statement that there is one aspect of St Thomas’s work that has not received due scrutiny as a literary form, one with solid dramatic qualities and structure: the Article. The Article is as Thomistic as the syllogism is Aristotelian. This particular mode of argument was evidently original with St. Thomas: he did not derive it from the work of any other writer, yet its inner movement is of the essence of dialectic, from the opening proposition to opposing objections, then “to the contrary” position as found in orthodoxy, and then the writer’s resolution, and so on. It is a variation on the classic sic-et-non, a reasonable, balanced to and fro of the sort beloved by disputants. No parallel or even parody of this Article is to be found in any known literature before or since the thirteenth century. The author aims to show that part of the sheer power of the Article resides in the fact that it has two levels of operation. The surface is composed of the dialectical to-and-fro adumbrated above. But under that surface lies a rhetorical structure constructed along the lines of the five divisions of the rhetorical logos as laid out by Cicero and Horace.

  14. Simultaneous Measurements of Electrostatic and Magnetic Fluctuations in ASDEX Upgrade Edge Plasma

    Ionita, Codrina; Vianello, Nicola; Müller, H.W.


    in such a way that simultaneously the poloidal and radial electric field components, the ion saturation current and the current-voltage characteristic can be registered. During the AUG discharges of 7 s lengths the probe head is inserted two to three times for 100 ms each by the midplane manipulator......In ASDEX Upgrade (AUG) electrostatic and magnetic fluctuations in the edge plasma region were measured simultaneously during ELMy H-mode (high confinement) plasmas and L-mode (low confinement) plasmas and during a transition between the two modes. A special probe was used containing six Langmuir...

  15. Compatibility of advanced tokamak plasma with high density and high radiation loss operation in JT-60U

    Takenaga, H.; Asakura, N.; Kubo, H.; Higashijima, S.; Konoshima, S.; Nakano, T.; Oyama, N.; Porter, G. D.; Rognlien, T. D.; Rensink, M. E.; Ide, S.; Fujita, T.; Takizuka, T.; Kamada, Y.; Miura, Y.; JT-60 Team


    Compatibility of advanced tokamak plasmas with high density and high radiation loss has been investigated in both reversed shear (RS) plasmas and high βp H-mode plasmas with a weak positive shear on JT-60U. In the RS plasmas, the operating regime is extended to high density above the Greenwald density (nGW) with high confinement (HHy2 > 1) and high radiation loss fraction (frad > 0.9) by tailoring the internal transport barriers (ITBs). With a small plasma-wall gap, the radiation loss in the main plasma (inside the magnetic separatrix) reaches 80% of the heating power due to metal impurity accumulation. However, high confinement of HHy2 = 1.2 is sustained even with such a large radiation loss in the main plasma. By neon seeding, the divertor radiation loss is enhanced from 20% to 40% of the total radiation loss. In the high βp H-mode plasmas, high confinement (HHy2 = 0.96) is maintained at high density ( \\bar{n}_{\\rme}/n_GW=0.92 ) with high radiation loss fraction (frad ~ 1) by utilizing high-field-side pellets and argon (Ar) injection. The high \\bar{n}_{\\rme}/n_GW is attributed to the formation of strong density ITB. Strong core-edge parameter linkage for confinement improvement is observed, where the pedestal pressure and the core plasma confinement increase together. The measured radiation profile including contributions from all impurities in the main plasma is peaked, and the central radiation is ascribed to the contribution from Ar accumulated inside the ITB. Impurity transport analyses indicate that the Ar density profile, twice as peaked as the electron density profile, which is the same level as that observed in the high βp H-mode plasma, can yield an acceptable radiation profile even with a peaked density profile in a fusion reactor.

  16. Texas Experimental Tokamak, a plasma research facility: Technical progress report

    Wootton, A.J.


    In the year just past, the authors made major progress in understanding turbulence and transport in both core and edge. Development of the capability for turbulence measurements throughout the poloidal cross section and intelligent consideration of the observed asymmetries, played a critical role in this work. In their confinement studies, a limited plasma with strong, H-mode-like characteristics serendipitously appeared and received extensive study though a diverted H-mode remains elusive. In the plasma edge, they appear to be close to isolating a turbulence drive mechanism. These are major advances of benefit to the community at large, and they followed from incremental improvements in diagnostics, in the interpretation of the diagnostics, and in TEXT itself. Their general philosophy is that the understanding of plasma physics must be part of any intelligent fusion program, and that basic experimental research is the most important part of any such program. The work here demonstrates a continuing dedication to the problems of plasma transport which continue to plague the community and are an impediment to the design of future devices. They expect to show here that they approach this problem consistently, systematically, and effectively.

  17. Relationship of GRACE risk score with Plasma Brain Natriuretic Peptide and Myeloperoxidase in Patients with Non- ST Segment el-evation Acute Coronary Syndrome%非ST段抬高急性冠状动脉综合征患者GRACE危险积分与血浆 BNP、MPO的相关性

    阚国庆; 高永; 王德启; 蔡忠贵; 王继征


    目的:探讨非 ST段抬高急性冠状动脉综合征(NSTE-ACS)患者全球急性冠状动脉事件注册(GRACE)评分与血浆脑钠肽( BNP)、髓过氧化酶(myeloperoxidase,MPO)水平的相关性。方法入选120例在我院住院的 NSTE-ACS患者,临床预测变量对其进行GRACE危险评分积分,并进行危险层次分层,入院后测定血浆 BNP、MPO水平。分析其与 GRACE危险积分不同层次之间的关系。结果①血浆 BNP、 MPO水平与GRACE危险积分呈正相关( r=0.71,P<0.05);随着 GRACE危险积分评分值增加,患者血浆 BNP、MPO水平亦逐渐升高;②随访期主要心血管事件发生率也增多(P <0.05)。结论 GRACE积分与BNP、MPO水平呈正相关,并与 NSTACS预后有关,能够对NSTEACS患者进行危险分层。%ObjectiveTo investigate the correlation of GRACE risk score and plasma brain natriuretic pep-tide ( BNP), myeloperoxidase in patients with non- ST segment elevation acute coronary syndrome.MethodsSelected 120 cases in NSTE-ACS patients in our hospital, clinical predictors its GRACE risk score points and dangerous level stratification, determination of plasma BNP, MPO levels after admission. Analyze the relationship between the different levels between the GRACE risk score.Results① The GRACE risk score is positively correlated with the plasma BNP and MPO levels ( r=0.71, P<0.05) ;② The incidence of MACE increased significantly with the rise of GRACE risk score and BNP, MPO levels.Conclusion: The higher GRACE risk score and BNP, MPO levels, the worse the prognosis, it could be use to predict the prognosis.

  18. Plasma turbulence

    Horton, W. [Univ. of Texas, Austin, TX (United States). Inst. for Fusion Studies; Hu, G. [Globalstar LP, San Jose, CA (United States)


    The origin of plasma turbulence from currents and spatial gradients in plasmas is described and shown to lead to the dominant transport mechanism in many plasma regimes. A wide variety of turbulent transport mechanism exists in plasmas. In this survey the authors summarize some of the universally observed plasma transport rates.

  19. Plasma harmonics

    Ganeev, Rashid A


    Preface; Why plasma harmonics? A very brief introduction Early stage of plasma harmonic studies - hopes and frustrations New developments in plasma harmonics studies: first successes Improvements of plasma harmonics; Theoretical basics of plasma harmonics; Basics of HHG Harmonic generation in fullerenes using few-cycle pulsesVarious approaches for description of observed peculiarities of resonant enhancement of a single harmonic in laser plasmaTwo-colour pump resonance-induced enhancement of odd and even harmonics from a tin plasmaCalculations of single harmonic generation from Mn plasma;Low-o

  20. Numerical and Experimental Investigation of Turbulent Transport Control via Shaping of Radial Plasma Flow Profiles

    Gilmore, Mark Allen [Univ. of New Mexico, Albuquerque, NM (United States)


    Turbulence, and turbulence-driven transport are ubiquitous in magnetically confined plasmas, where there is an intimate relationship between turbulence, transport, instability driving mechanisms (such as gradients), plasma flows, and flow shear. Though many of the detailed physics of the interrelationship between turbulence, transport, drive mechanisms, and flow remain unclear, there have been many demonstrations that transport and/or turbulence can be suppressed or reduced via manipulations of plasma flow profiles. This is well known in magnetic fusion plasmas [e.g., high confinement mode (H-mode) and internal transport barriers (ITB’s)], and has also been demonstrated in laboratory plasmas. However, it may be that the levels of particle transport obtained in such cases [e.g. H-mode, ITB’s] are actually lower than is desirable for a practical fusion device. Ideally, one would be able to actively feedback control the turbulent transport, via manipulation of the flow profiles. The purpose of this research was to investigate the feasibility of using both advanced model-based control algorithms, as well as non-model-based algorithms, to control cross-field turbulence-driven particle transport through appropriate manipulation of radial plasma flow profiles. The University of New Mexico was responsible for the experimental portion of the project, while our collaborators at the University of Montana provided plasma transport modeling, and collaborators at Lehigh University developed and explored control methods.

  1. The density limit in JET diverted plasmas

    Campbell, D.J.; Clement, S.; Gottardi, N.; Gowers, C.; Harbour, P.; Loarte, A.; Horton, L.; Lingertat, J.; Lowry, C.G.; Saibene, G.; Stamp, M.; Stork, D. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Monk, R. [Royal Holloway Coll., London (United Kingdom). Dept. of Physics


    In JET limiter plasmas the density limit is associated with radiated power fractions of 100% and, in plasmas with carbon limiters, it is invariably disruptive. However, in discharges with solid beryllium limiters the limit is identified with the formation of a MARFE and disruptions are less frequent. In addition, the improved conditioning of the vessel arising from the use of beryllium has significantly improved the density limit scaling, so that the maximum density rises with the square root of the input power. In diverted plasmas several confinement regimes exist, making the characterization of the density limit more complex. While the density limit in L-mode plasmas is generally disruptive, the limit in ELMy and ELM-free H-modes generally prompts a return to the L-mode and a disruption is not inevitable. The density limit does rise with the increasing power, but the L-to-H transition complicates the analysis. Nevertheless, at low plasma currents (<2 MA), densities significantly above the Greenwald limit can be achieved, while at higher currents power handling limitations have constrained the range of density which can be achieved. (authors). 7 refs., 4 figs.

  2. Deuterium-tritium TFTR plasmas in the high poloidal beta regime

    Sabbagh, S.A.; Mauel, M.E.; Navratil, G.A. [Columbia Univ., New York, NY (United States). Dept. of Applied Physics] [and others


    Deuterium-tritium plasmas with enhanced energy confinement and stability have been produced in the high poloidal beta, advanced tokamak regime in TFTR. Confinement enhancement H {triple_bond} {tau}{sub E}/{tau}{sub E ITER-89P} > 4 has been obtained in a limiter H-mode configuration at moderate plasma current I{sub p} = 0.85 {minus} 1.46 MA. By peaking the plasma current profile, {beta}{sub N dia} {triple_bond} 10{sup 8} < {beta}{sub t{perpendicular}} > aB{sub 0}/I{sub p} = 3 has been obtained in these plasma,s exceeding the {beta}{sub N} limit for TFTR plasmas with lower internal inductance, l{sub i}. Fusion power exceeding 6.7 MW with a fusion power gain Q{sub DT} = 0.22 has been produced with reduced alpha particle first orbit loss provided by the increased l{sub i}.

  3. Experimental studies of high-confinement mode plasma response to non-axisymmetric magnetic perturbations in ASDEX Upgrade

    Suttrop, W.; Kirk, A.; Nazikian, R.; Leuthold, N.; Strumberger, E.; Willensdorfer, M.; Cavedon, M.; Dunne, M.; Fischer, R.; Fietz, S.; Fuchs, J. C.; Liu, Y. Q.; McDermott, R. M.; Orain, F.; Ryan, D. A.; Viezzer, E.; The ASDEX Upgrade Team; The DIII-D Team; The Eurofusion MST1 Team


    The interaction of externally applied small non-axisymmetric magnetic perturbations (MP) with tokamak high-confinement mode (H-mode) plasmas is reviewed and illustrated by recent experiments in ASDEX Upgrade. The plasma response to the vacuum MP field is amplified by stable ideal kink modes with low toroidal mode number n driven by the H-mode edge pressure gradient (and associated bootstrap current) which is experimentally evidenced by an observable shift of the poloidal mode number m away from field alignment (m  =  qn, with q being the safety factor) at the response maximum. A torque scan experiment demonstrates the importance of the perpendicular electron flow for shielding of the resonant magnetic perturbation, as expected from a two-fluid MHD picture. Two significant effects of MP occur in H-mode plasmas at low pedestal collisionality, ν \\text{ped}\\ast≤slant 0.4 : (a) a reduction of the global plasma density by up to 61 % and (b) a reduction of the energy loss associated with edge localised modes (ELMs) by a factor of up to 9. A comprehensive database of ELM mitigation pulses at low {ν\\ast} in ASDEX Upgrade shows that the degree of ELM mitigation correlates with the reduction of pedestal pressure which in turn is limited and defined by the onset of ELMs, i. e. a modification of the ELM stability limit by the magnetic perturbation.

  4. Dusty plasmas

    Fortov, Vladimir E; Khrapak, Aleksei G; Molotkov, Vladimir I; Petrov, Oleg F [Institute for High Energy Densities, Associated Institute for High Temperatures, Russian Academy of Sciences, Moscow (Russian Federation); Khrapak, Sergei A [Max-Planck-Institut fur Extraterrestrische Physik, Garching (Germany)


    The properties of dusty plasmas - low-temperature plasmas containing charged macroparticles - are considered. The most important elementary processes in dusty plasmas and the forces acting on dust particles are investigated. The results of experimental and theoretical investigations of different states of strongly nonideal dusty plasmas - crystal-like, liquid-like, gas-like - are summarized. Waves and oscillations in dusty plasmas, as well as their damping and instability mechanisms, are studied. Some results on dusty plasma investigated under microgravity conditions are presented. New directions of experimental research and potential applications of dusty plasmas are discussed. (reviews of topical problems)

  5. St. Vincent Handwritten History Notes

    US Fish and Wildlife Service, Department of the Interior — This document gives historical highlights of St. Vincent Island from the Creek and Seminole Native Americans who inhabited the island in the 1700's to the Loomis...

  6. St. John's Wort and Depression

    ... W X Y Z St. John's Wort and Depression: In Depth Share: On This Page Introduction Key ... will help ensure coordinated and safe care. About Depression Depression is a medical condition that affects about ...

  7. St. Vincent History Research Correspondence

    US Fish and Wildlife Service, Department of the Interior — This document contains a series of letters about the locations of the Confederate fortress that existed on St. Vincent Island during the Civil War.

  8. Herrens röst

    Rösing, Lilian Munk


    Om språket är gränsen mellan djur och människor, vad innebär det när hundar talar? I filmen Upp pratar de animerade hundarna, men med sin husses röst. Lilian Munk Rösing ser filmen i sällskap av bland andra Jacques Lacan, Slavoj Žižek och Renata Salecl och finner en röst utan kropp, en kropp...

  9. Simulation of triton burn-up in JET plasmas

    Loughlin, M.J.; Balet, B.; Jarvis, O.N.; Stubberfield, P.M. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking


    This paper presents the first triton burn-up calculations for JET plasmas using the transport code TRANSP. Four hot ion H-mode deuterium plasmas are studied. For these discharges, the 2.5 MeV emission rises rapidly and then collapses abruptly. This phenomenon is not fully understood but in each case the collapse phase is associated with a large impurity influx known as the ``carbon bloom``. The peak 14 MeV emission occurs at this time, somewhat later than that of the 2.5 MeV neutron peak. The present results give a clear indication that there are no significant departures from classical slowing down and spatial diffusion for tritons in JET plasmas. (authors). 7 refs., 3 figs., 1 tab.

  10. Gyrokinetic particle simulation of neoclassical transport in the pedestal/scrape-off region of a tokamak plasma

    Ku, S [Courant Institute of Mathematical Sciences, New York University (United States); Chang, C-S [Courant Institute of Mathematical Sciences, New York University (United States); Adams, M [Columbia University (United States); Cummings, J [California Institute of Technology (United States); Hinton, F [Hinton Associates (United States); Keyes, D [Columbia University (United States); Klasky, S [Oak Ridge National Laboratory (United States); Lee, W [Princeton Plasma Physics Laboratory (United States); Lin, Z [University of California at Irvine (United States); Parker, S [University of Colorado at Boulder (United States)


    A gyrokinetic neoclassical solution for a diverted tokamak edge plasma has been obtained for the first time using the massively parallel Jaguar XT3 computer at Oak Ridge National Laboratory. The solutions show similar characteristics to the experimental observations: electric potential is positive in the scrape-off layer and negative in the H-mode layer, and the parallel rotation is positive in the scrape-off layer and at the inside boundary of the H-mode layer. However, the solution also makes a new physical discovery that there is a strong ExB convective flow in the scrape-off plasma. A general introduction to the edge simulation problem is also presented.

  11. Comparison between measured scrape-off layer plasma parameters and 2D model calculations for JET X-point discharges

    Loarte, A. [JET Joint Undertaking, Abingdon, Oxon, OX14 3EA (United Kingdom); Chankin, A. [JET Joint Undertaking, Abingdon, Oxon, OX14 3EA (United Kingdom); Clement, S. [JET Joint Undertaking, Abingdon, Oxon, OX14 3EA (United Kingdom); Corrigan, G. [JET Joint Undertaking, Abingdon, Oxon, OX14 3EA (United Kingdom); Harbour, P. [JET Joint Undertaking, Abingdon, Oxon, OX14 3EA (United Kingdom); Horton, L. [JET Joint Undertaking, Abingdon, Oxon, OX14 3EA (United Kingdom); Janeschitz, G. [JET Joint Undertaking, Abingdon, Oxon, OX14 3EA (United Kingdom); Lingertat, J. [JET Joint Undertaking, Abingdon, Oxon, OX14 3EA (United Kingdom); Matthews, G. [JET Joint Undertaking, Abingdon, Oxon, OX14 3EA (United Kingdom); Simonini, R. [JET Joint Undertaking, Abingdon, Oxon, OX14 3EA (United Kingdom); Tagle, J.A. [JET Joint Undertaking, Abingdon, Oxon, OX14 3EA (United Kingdom); Taroni, A. [JET Joint Undertaking, Abingdon, Oxon, OX14 3EA (United Kingdom); Vlases, G. [JET Joint Undertaking, Abingdon, Oxon, OX14 3EA (United Kingdom)


    Modelling with the EDGE2D/U-NIMBUS code of the measured scrape-off layer plasma parameters for JET divertor discharges is presented. Model results agree with the experiment if very small values (< or {approx}0.1 m{sup 2}/s in H-modes and low power L-modes) for the anomalous particle transport diffusion coefficient in the SOL are used. While the assumption of the power flow out of the main plasma being carried equally by the electrons and the ions describes satisfactorily the global power balance for Ohmic and L-mode discharges, more power flowing out through the ion channel is consistent with the power balance in hot ion H-modes. Some sensitivity studies of the code results on the modelling hypothesis are discussed. ((orig.)).

  12. Plasma-Material Interface Development for Future Spherical Tokamak-based Devices in NSTX.

    et. al, V


    The divertor plasma-material interface (PMI) must be able to withstand steady-state heat fluxes up to 10 MW/m{sup 2} (a limit imposed by the present day divertor material and engineering constraints) with minimal material erosion, as well as to provide impurity control and ion density pumping capabilities. In spherical tokamaks (STs), the compact divertor geometry and the requirement of low core electron collisionality n*{sub e} at n{sub e} < 0.5-0.7 n{sub G} (where n{sub G} is the Greenwald density) for increased neutral beam current drive efficiency impose much greater demands on divertor and first-wall particle and heat flux mitigation solutions. In NSTX, divertor heat flux mitigation and impurity control with an innovative 'snowflake' divertor configuration and ion density pumping by evaporated lithium wall and divertor coatings are studied. Lithium coatings have enabled ion density reduction up to 50% in NSTX through the reduction of wall and divertor recycling rates. The 'snowflake' divertor configuration was obtained in NSTX in 0.8-1 MA 4-6 MW NBI-heated H-mode lithium-assisted discharges using three divertor coils. The snowflake divertor formation was always accompanied by a partial detachment of the outer strike point with an up to 50% increase in divertor radiation from intrinsic carbon, the peak divertor heat flux reduction from 3-6 MW/m{sup 2} to 0.5-1 MW/m{sup 2}, and a significant increase in divertor volume recombination. High core confinement was maintained with the snowflake divertor, evidenced by the t{sub E}, W{sub MHD} and the H98(y,2) factors similar to those of the standard divertor discharges. Core carbon concentration and radiated power were reduced by 30-70%, apparently as a result of reduced divertor physical and chemical sputtering in the snowflake divertor and ELMs. In the SFD discharges, the MHD stability of the H-mode pedestal region was altered leading to the re-appearance of medium size (DW/W = 5-10%), Type I

  13. High performance deuterium-tritium plasmas in TFTR

    Sabbagh, S.A. [Columbia Univ., New York, NY (United States). Dept. of Applied Physics; Batha, S.H. [Fusion Physics and Technology, Torrance, CA (United States); Bell, M.G. [Princeton Univ., NJ (United States). Plasma Physics Lab.] [and others


    Plasmas composed of nominally equal concentrations of deuterium and tritium (DT) have been created in TFTR with the goals of producing significant levels of fusion power and of examining the effects of DT fusion alpha particles. Conditioning of the limiter by the injection of lithium pellets has led to an approximate doubling of the energy confinement time, {tau}{sub E}, in supershot plasmas at high plasma current (I{sub p} {le} 2.5 MA) and high heating power (P{sub b} {le} 33 MW). Operation with DT typically results in an additional 20% increase in {tau}{sub E}. In the high poloidal beta, advanced tokamak regime in TFTR, confinement enhancement H {triple_bond} {tau}{sub E}/{tau}{sub E ITER-89P} > 4 has been obtained in a limiter H-mode configuration at moderate plasma current I{sub p} = 0.85 {minus} 1.5 MA. By peaking the plasma current profile, {beta}{sub N dia} {triple_bond} 10{sup 8} < {beta}{sub t{perpendicular}} > aB{sub 0}/I{sub p} = 3 has been obtained in these plasmas, exceeding the {beta}{sub N} limit for TFTR plasmas with lower internal inductance, l{sub i}. Confinement of alpha particles appears to be classical and losses due to collective effects have not been observed. While small fluctuations in fusion product loss were observed during ELMs, no large loss was detected in DT plasmas.

  14. Plasma waves

    Swanson, DG


    Plasma Waves discusses the basic development and equations for the many aspects of plasma waves. The book is organized into two major parts, examining both linear and nonlinear plasma waves in the eight chapters it encompasses. After briefly discussing the properties and applications of plasma wave, the book goes on examining the wave types in a cold, magnetized plasma and the general forms of the dispersion relation that characterize the waves and label the various types of solutions. Chapters 3 and 4 analyze the acoustic phenomena through the fluid model of plasma and the kinetic effects. Th

  15. Plasma astrophysics

    Kaplan, S A; ter Haar, D


    Plasma Astrophysics is a translation from the Russian language; the topics discussed are based on lectures given by V.N. Tsytovich at several universities. The book describes the physics of the various phenomena and their mathematical formulation connected with plasma astrophysics. This book also explains the theory of the interaction of fast particles plasma, their radiation activities, as well as the plasma behavior when exposed to a very strong magnetic field. The text describes the nature of collective plasma processes and of plasma turbulence. One author explains the method of elementary

  16. Soluble ST2 plasma concentrations predict mortality in severe sepsis

    J.J. Hoogerwerf; M.W.T. Tanck; M.A.D. van Zoelen; X. Wittebole; P.F. Laterre; T. van der Poll


    Patients with sepsis-after surviving the initial hyperinflammatory phase-display features consistent with immunosuppression, including hyporesponsiveness of immunocompetent cells to bacterial agents. Immunosuppression is thought to be facilitated by negative regulators of toll-like receptors, includ

  17. Soluble ST2 plasma concentrations predict mortality in severe sepsis

    Hoogerwerf, J.J.; Tanck, M.W.T.; van Zoelen, M.A.D.; Wittebole, X.; Laterre, P.F.; van der Poll, T.


    Patients with sepsis-after surviving the initial hyperinflammatory phase-display features consistent with immunosuppression, including hyporesponsiveness of immunocompetent cells to bacterial agents. Immunosuppression is thought to be facilitated by negative regulators of toll-like receptors,

  18. A Proposed Experiment to Study Relaxation Formation of a Spherical Tokamak with a Plasma Center Column

    Hsu, S C


    A spherical tokamak (ST) with a plasma center column (PCC) can be formed via driven magnetic relaxation of a screw pinch plasma. An ST-PCC could in principle eliminate many problems associated with a material center column, a key weakness of the ST reactor concept. This work summarizes the design space for an ST-PCC in terms of flux amplification, aspect ratio, and elongation, based on the zero-beta Taylor-relaxed analysis of Tang & Boozer [Phys. Plasmas 13, 042514 (2006)]. The paper will discuss (1) equilibrium and stability properties of the ST-PCC, (2) issues for an engineering design, and (3) key differences between the proposed ST-PCC and the ongoing Proto-Sphera effort in Italy.

  19. Proposed Experiment to Study Relaxation Formation of a Spherical Tokamak with a Plasma Center Column

    Hsu, S. C.; Tang, X. Z.


    A spherical tokamak (ST) with a plasma center column (PCC) can be formed via driven magnetic relaxation of a screw pinch plasma. An ST-PCC could in principle eliminate many problems associated with a material center column, a key weakness of the ST reactor concept. This work summarizes the design space for an ST-PCC in terms of flux amplification, aspect ratio, and elongation, based on the zero-β Taylor-relaxed analysis of Tang & Boozer [Phys. Plasmas 13, 042514 (2006)]. The paper will discuss (1) equilibrium and stability properties of the ST-PCC, (2) issues for an engineering design, and (3) key differences between the proposed ST-PCC and the ongoing Proto-Sphera effort in Italy.

  20. Modulating toroidal flow stabilization of edge localized modes with plasma density

    Cheng, Shikui; Banerjee, Debabrata


    Recent EAST experiments have demonstrated mitigation and suppression of edge localized modes (ELMs) with toroidal rotation flow in higher collisionality regime, suggesting potential roles of plasma density. In this work, the effects of plasma density on the toroidal flow stabilization of the high-$n$ edge localized modes have been extensively studied in linear calculations for a circular-shaped limiter H-mode tokamak, using the extended MHD code NIMROD. In the single MHD model, toroidal flow has a weak stabilizing effects on the high-$n$ modes. Such a stabilization, however, can be significantly enhanced with the increase in plasma density. Furthermore, our calculations show that the enhanced stabilization of high-$n$ modes from toroidal flow with higher edge plasma density persists in the 2-fluid MHD model. These findings may explain the ELM mitigation and suppression by toroidal rotation in higher collisionality regime due to the enhancement of plasma density obtained in recent EAST experiments.

  1. Flow shear induced fluctuation suppression in finite aspect ratio shaped tokamak plasma

    Hahm, T.S. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Burrell, K.H. [General Atomics, San Diego, CA (United States)


    The suppression of turbulence by the E {times} B flow shear and parallel flow shear is studied in an arbitrary shape finite aspect ratio tokamak plasma using the two point nonlinear analysis previously utilized in a high aspect rat& tokamak plasma. The result shows that only the E {times} B flow shear is responsible for the suppression of flute-like fluctuations. This suppression occurs regardless of the plasma rotation direction and is therefore, relevant for the VH mode plasma core as well as for the H mode plasma edge. Experimentally observed in-out asymmetry of fluctuation reduction behavior can be addressed in the context of flux expansion and magnetic field pitch variation on a given flux surface. The adverse effect of neutral particles on confinement improvement is also discussed in the context of the charge exchange induced parallel momentum damping.

  2. Growth curve analysis for plasma profiles using smoothing splines. Final report, January 1993--January 1995

    Imre, K.


    In this project, we parameterize the shape and magnitude of the temperature and density profiles on JET and the temperature profiles on TFTR. The key control variables for the profiles were tabulated and the response functions were estimated. A sophisticated statistical analysis code was developed to fit the plasma profiles. Our analysis indicate that the JET density shape depends primarily on {bar n}/B{sub t} for Ohmic heating, {bar n} for L-mode and I{sub p} for H-mode. The temperature profiles for JET are mainly determined by q{sub 95} for the case of Ohmic heating, and by B{sub t} and P/{bar n} for the L-mode. For the H-mode the shape depends on the type of auxiliary heating, Z{sub eff}, N{bar n}, q{sub 95}, and P.

  3. Soluble ST2 levels are associated with bleeding in patients with severe Leptospirosis.

    Jiri F P Wagenaar

    Full Text Available BACKGROUND: Severe leptospirosis features bleeding and multi-organ failure, leading to shock and death. Currently it is assumed that both exaggerated inflammation and immune suppression contribute to mortality in sepsis. Indeed, several proinflammatory cytokines are reported to be induced during leptospirosis. Toll-like receptors, which play an important role in the initiation of an innate immune response, are inhibited by negative regulators including the membrane-bound ST2 (mST2 receptor. Soluble ST2 (sST2 has been implicated to inhibit signaling through mST2. The aim of this study was to determine the extent of sST2 and (pro- inflammatory cytokine release in patients with severe leptospirosis. METHODOLOGY AND PRINCIPAL FINDINGS: In an observational study, 68 consecutive cases of severe leptospirosis were included. Soluble ST2 and cytokines (TNF-alpha, IL-1beta, IL-6, IL-8, and IL-10 were repeatedly measured. To determine whether blood cells are a source of sST2 during infection, we undertook an in vitro experiment: human whole blood and peripheral blood mononuclear cells (PBMC were stimulated with viable pathogenic Leptospira. All patients showed elevated sST2, IL-6, IL-8, and IL-10 levels on admission. Admission sST2 levels correlated with IL-6, IL-8, and IL-10. Thirty-four patients (50% showed clinical bleeding. Soluble ST2 levels were significantly associated with bleeding overall (OR 2.0; 95%CI: 1.2-3.6 and severe bleeding (OR 5.1; 95%CI: 1.1-23.8. This association was unique, since none of the cytokines showed this correlation. Moreover, sST2 was associated with mortality (OR 2.4; 95%CI: 1.0-5.8. When either whole blood or isolated PBMCs were stimulated with Leptospira in vitro, no sST2 production could be detected. CONCLUSIONS: Patients with severe leptospirosis demonstrated elevated plasma sST2 levels. Soluble ST2 levels were associated with bleeding and mortality. In vitro experiments showed that (white blood cells are probably not

  4. Unraveling the Mystery of Stöber Silica's Microporosity.

    Li, Shanshan; Wan, Quan; Qin, Zonghua; Fu, Yuhong; Gu, Yuantao


    Puzzling aspects of the microporous structure of Stöber silica, including inconsistencies in the BET specific surface area and the long measurement time required for N2 adsorption, hinder further research on and potential applications of this material. In this work, Stöber silica samples prepared using systematic and detailed post-treatment methods were characterized by N2 adsorption, scanning electron microscopy, transmission electron microscopy, inductively coupled plasma optical emission spectrometry, elemental analysis, and Fourier transform infrared spectroscopy. We have found that the often overlooked sample preparation conditions may be the main causes that perplex the gas adsorption characterization results of Stöber silica samples. The pore-blocking processes associated with a variety of sample treatment methods are discussed in detail. Strong evidence for the particle growth model and pore-blocking mechanism involving ethoxyl groups, Si species, and condensation of silanols is provided. A remarkable result is that the measurement time is shortened from 1 month in our previous work to 2-3 days for samples with large specific surface areas. A suitable post-treatment condition is recommended to obtain microporous Stöber silica with a short measurement time, including water washing, low temperature drying without a vacuum, and a short storage time.

  5. St. Louis FUSRAP Lessons Learned

    Eberlin, J.; Williams, D.; Mueller, D.


    The purpose of this paper is to present lessons learned from fours years' experience conducting Remedial Investigation and Remedial Action activities at the St. Louis Downtown Site (SLDS) under the Formerly Utilized Sites Remedial Action Program (FUSRAP). Many FUSRAP sites are experiencing challenges conducting Remedial Actions within forecasted volume and budget estimates. The St. Louis FUSRAP lessons learned provide insight to options for cost effective remediation at FUSRAP sites. The lessons learned are focused on project planning (budget and schedule), investigation, design, and construction.

  6. SDBD plasma jet for skin disinfection

    Creyghton, Y.L.M.; Meijer, S.R.; Verweij, P.E.; Zanden, F. van der; Leenders, P.H.M.


    A consortium consisting of the research institute TNO, the medical university and hospital St Radboud and two industrial enterprises is working on a non-thermal plasma treatment method for skin and wound disinfection. The group is seeking for cooperation, in particular in the field of validation

  7. SDBD plasma jet for skin disinfection

    Creyghton, Y.L.M.; Meijer, S.R.; Verweij, P.E.; Zanden, F. van der; Leenders, P.H.M.


    A consortium consisting of the research institute TNO, the medical university and hospital St Radboud and two industrial enterprises is working on a non-thermal plasma treatment method for skin and wound disinfection. The group is seeking for cooperation, in particular in the field of validation met

  8. ST-segment elevation: Distinguishing ST elevation myocardial infarction from ST elevation secondary to nonischemic etiologies

    Alok; Deshpande; Yochai; Birnbaum


    The benefits of early perfusion in ST elevation myocardial infarctions(STEMI) are established; howeverearly perfusion of non-ST elevation myocardial infarctions has not been shown to be beneficial. In additionST elevation(STE) caused by conditions other thanacute ischemia is common. Non-ischemic STE may beconfused as STEMI, but can also mask STEMI on electrocardiogram(ECG). As a result, activating the primarypercutaneous coronary intervention(pPCI) protocooften depends on determining which ST elevation patterns reflect transmural infarction due to acute coronary artery thrombosis. Coordination of interpreting theECG in its clinical context and appropriately activatingthe pPCI protocol has proved a difficult task in borderline cases. But its importance cannot be ignored, asreflected in the 2013 American College of CardiologyFoundation/American Heart Association guidelines concerning the treatment of ST elevation myocardial infarction. Multiples strategies have been tested and studiedand are currently being further perfected. No mattethe strategy, at the heart of delivering the best care lies rapid and accurate interpretation of the ECG. Here, we present the different patterns of non-ischemic STE and methods of distinguishing between them. In writing this paper, we hope for quicker and better stratification of patients with STE on ECG, which will lead to be bet-ter outcomes.

  9. Linear Analysis of Drift Ballooning Modes in Tokamak Edge Plasmas

    Tangri, Varun; Kritz, Arnold; Rafiq, Tariq; Pankin, Alexei


    The H-mode pedestal structure depends on the linear stability of drift ballooning modes (DBMs) in many H-mode pedestal models. Integrated modeling that uses these pedestal models requires fast evaluation of linear stability of DBMs. Linear analysis of DBMs is also needed in the computations of effective diffusivities associated with anomalous transport that is driven by the DBMs in tokamak edge plasmas. In this study several numerical techniques of linear analysis of the DBMs are investigated. Differentiation matrix based spectral methods are used to compute the physical eigenvalues of the DBMs. The model for DBMs used here consists of six differential equations [T. Rafiq et al. Phys. Plasmas, 17, 082511, (2010)]. It is important to differentiate among non-physical (numerical) modes and physical modes. The determination of the number of eigenvalues is solved by a computation of the `nearest' and `ordinal' distances. The Finite Difference, Hermite and Sinc based differentiation matrices are used. It is shown that spectral collocation methods are more accurate than finite difference methods. The technique that has been developed for calculating eigenvalues is quite general and is relevant in the computation of other modes that utilize the ballooning mode formalism.

  10. The 2015 St Patrick's Day Storm: Origins

    Carlyle, Jack; van Driel-Gesztelyi, Lidia; Zuccarello, Francesco; James, Alexander; Williams, David


    The magnetic storm experienced at Earth on St. Patrick's Day 2015 had been the strongest of cycle 24 (at that time) with a measured DST of -223 nT, though it was not expected to cause much of a disturbance. In this work we study the solar source region of several peculiar eruptions, leading to the formation and destruction of various structures, in the week leading up to the storm, and determine the true sequence of events. The evolution of the magnetic flux at the solar surface is examined in order to place suspected flux-ropes into context, and the evolution of the magnetic connectivities is described alongside a PFSS model of the surrounding region. The balance between positive and negative flux directly before two key eruptions is investigated in detail, in order to ascertain whether particular trigger mechanisms are feasible explanations. As well as these magnetic investigations, the column density of plasma involved is calculated from extreme ultraviolet images, and this is used to estimate the total mass of one filament, as well as select other features relevant to the eruptions. This information is then used to comment on the energy budgets and requirements of several processes in order to best understand the underlying drivers of this event.Previous studies on the St. Patrick's Day Storm are also incorporated into this work, and an attempt is made to reconcile the disparate conclusions drawn by the scientific community as to why this storm was not only so effective, but also a major forecasting failure.

  11. 1st EUCOMAS conference



    simple numerical model supports the development of FSW technology. ABiTAS - Advanced Bonding Technologies for Aircraft Structures. Individual Laser Cladding for High Pressure Turbine Blades. Advanced high temperature repair brazing for single crystal and directionally solidified turbine components. Thermoplastic Tape Placement - Challenging the Autoclave Process. Modern Methods of Preforming Titanium Alloys for Forging Aero Engine Vanes. Ultrasonic Shot Peening for Ti-6Al-4V Aero-Engine Components. Stiffening spherical panels by means of modern braiding processes. Potential and Challenges of Fibre Reinforced Ceramics in Gas Turbines. Development of a nickel alloy for disc applications. Application of Thermal Barrier Coatings on Intermetallic Turbine Blade Materials. Development and Validation of A Dual Titanium Alloy Dual-Microstructure BLISK. PTAH-Socar Fuel-Cooled Composite Materials Structure. Manufacturing Methods and Typical Applications of C/C-SiC Materials Based on the Liquid Silicon Infiltration Process (LSI) - Non brittle C/C-SiC materials based on filament winding. Dilution phenomenon during coating of titanium alloys by Plasma Transferred Arc (PTA) process. Tools, processes and examples of Space Structures Optimisation. Topology Optimisation in the Design Process of Light Weight Structural Components for Aeroengines. Residual strength prediction of integral structures using numerical crack extension analyses. Finite element based optimization of a novel metal-composite-joint. Investigations on the pulsed MIG/MAG welding of dissimilar austenitic-ferritic steels (W7335-X10CrNiTi18.9). Isothermal Oxidation Behaviour and Microstructure of the single crystal superalloy PWA 1483 at 950 C. The Use of Fluorine for the Protection of TiAl-Components against High-Temperature Oxidation. Stability Estimation for Stiffened Structures Considering Laser Beam Welded Stringers - comparision of methods to estimate fuselage buckling behaviour. New design concept for integral

  12. Impaired Glucose Tolerance in Healthy Men Treated with St. John's Wort.

    Stage, Tore Bjerregaard; Damkier, Per; Christensen, Mette Marie Hougaard; Nielsen, Lene Buch-Krogh; Højlund, Kurt; Brøsen, Kim


    The purpose of this study was to examine whether the over-the-counter herbal medicinal plant St. John's wort affects glucose tolerance in healthy men. To do this, we included 10 healthy men who were examined by a 2-hr oral glucose tolerance test on three occasions: A: baseline; B: after 21 days of treatment with St. John's wort; and C: at least 6 weeks after the last capsule of St. John's wort was ingested. Plasma glucose, serum insulin and C-peptide levels were measured during an oral glucose tolerance test and used for estimation of area under the concentration-time curve (AUC) as well as indices of insulin sensitivity and insulin secretion. We found that treatment with St. John's wort increased total and incremental glucose AUC and 2-hr plasma glucose levels. Surprisingly, this effect was sustained and even further increased 6 weeks after the last capsule of St. John's wort was taken. No effect on indices of insulin sensitivity was seen, but indices of insulin secretion were reduced even after adjustment for insulin sensitivity. In conclusion, this study indicates that long-term treatment with St. John's wort may impair glucose tolerance by reducing insulin secretion in young, healthy men. The unregulated use of this over-the-counter drug might be a risk factor for impaired glucose tolerance and type 2 diabetes.

  13. The Danish St. Croix Project

    J. Douma, Michael; Rasmussen, Anders Bo


    Working from previously unknown sources in Danish archives, this article establishes for the first time the important role that the island of St. Croix played in the Lincoln Administration’s considerations on colonizing African Americans abroad. The paper argues that U.S. Secretary of State William...

  14. Correlation between admission plasma glucose level and cardiac insufficiency or GRACE scores in patients with acute ST-segment elevation myocardial infarction%急性ST段抬高型心肌梗死患者入院血糖水平与心功能不全和GRACE评分的相关性分析

    白玉蓉; 靳志涛; 鞠鹏; 卢鑫


    目的:探讨急性ST段抬高型心肌梗死(STEMI)患者入院血糖水平与心功能不全和GRACE评分的相关性。方法连续入选2007年1月至2009年12月因STEMI住院的患者244例,收集其人口学信息和临床资料并进行GRACE危险评分。根据入院随机血糖水平分为3组:Ⅰ组(血糖<7 mmol/L,n=102);Ⅱ组(7 mmol/L≤血糖<11 mmol/L,n=102),Ⅲ组(血糖≥11 mmol/L,n=40)。分析其入院随机血糖水平和心功能不全、GRACE危险评分的关系。结果Ⅰ组、Ⅱ组、Ⅲ组患者随着血糖水平升高,女性患者(5.9%vs.17.6%vs.25.0%,P<0.05)及糖尿病患者(8.9%vs.33.3%vs.95.0%,P<0.05)比例增加。Ⅰ组患者心功能不全比例少于Ⅱ组及Ⅲ组(15.7%vs.23.5%vs.25.0%,P<0.05);GRACE评分值低于Ⅱ组及Ⅲ组及Ⅱ组[(148.7±33.1)vs.(160.0±37.6)vs.(171.5±41.2),P<0.05],而Ⅱ组及Ⅲ组心功能不全患者比例及GRACE评分无统计学差异(P>0.05)。相关分析表明入院即刻血糖水平与GRACE危险性评分(r=0.77,P=0.009)和心功能不全(tau_b=0.248,P<0.0001)有显著相关性。结论 STEMI患者入院应激性血糖水平升高与住院心力衰竭和GRACE评分密切相关。无论是糖尿病还是非糖尿病患者,入院即刻血糖水平大于7 mmol/L时心力衰竭发生率明显增加。%Objective To investigate the correlation between admission plasma glucose level and cardiac insufficiency or GRACE scores in patients with acute ST-segment elevation myocardial infarction (STEMI). Methods STEMI patients (n=244) were chosen from Jan. 2007 to Dec. 2009, and their demographic information and clinical data were collected and given GRACE risk scoring. All patients were divided, according their admission glucose level, into 3 groups: group I (glucose0.05). Correlation analysis showed that admission plasma glucose level was significantly correlated to GRACE scores (r=0.77,P=0

  15. Comparison of heat effects associated with metal cutting method on ST 37 alloy steel

    L. Dahil


    Full Text Available In this study, by examining effects of the heat on the cut surface of material formed by the processes, such as Plasma, Laser, Wire Erosion applied on St 37 alloy steel material, it has been determined that minimum cutting damage occurs in wire erosion process.

  16. Influence of plasma pedestal profiles on access to ELM-free regimes in ITER

    Medvedev, S. Yu.; Ivanov, A. A.; Martynov, A. A.; Poshekhonov, Yu. Yu.; Konovalov, S. V.; Polevoi, A. R.


    The influence of current density and pressure gradient profiles in the pedestal on the access to the regimes free from edge localized modes (ELMs) like quiescent H-mode in ITER is investigated. Using the simulator of MHD modes localized near plasma boundary based on the KINX code, calculations of the ELM stability were performed for the ITER plasma in scenarios 2 and 4 under variations of density and temperature profiles with the self-consistent bootstrap current in the pedestal. Low pressure gradient values at the separatrix, the same position of the density and temperature pedestals and high poloidal beta values facilitate reaching high current density in the pedestal and a potential transition into the regime with saturated large scale kink modes. New version of the localized MHD mode simulator allows one to compute the growth rates of ideal peeling-ballooning modes with different toroidal mode numbers and to determine the stability region taking into account diamagnetic stabilization. The edge stability diagrams computations and sensitivity studies of the stability limits to the value of diamagnetic frequency show that diamagnetic stabilization of the modes with high toroidal mode numbers can help to access the quiescent H-mode even with high plasma density but only with low pressure gradient values at the separatrix. The limiting pressure at the top of the pedestal increases for higher plasma density. With flat density profile the access to the quiescent H-mode is closed even with diamagnetic stabilization taken into account, while toroidal mode numbers of the most unstable peeling-ballooning mode decrease from n = 10-40 to n = 3-20.

  17. Plasma Antenna

    N M Vijay


    The fundamental base of plasma antenna is the use of an ionized medium as a conductor. The plasma antenna is a radiofrequency antenna formed by a plasma columns, Filaments or sheets, which are excited by a surface wave. The relevance of this device is how rapidly it can be turned on and off, only applying an electrical pulse. Besides its wide carrier frequency, the great directivity and controllable antenna shape. Otherwise a disadvantage is that it needs energy to be ionized....

  18. Plasma physics

    Drummond, James E


    A historic snapshot of the field of plasma physics, this fifty-year-old volume offers an edited collection of papers by pioneering experts in the field. In addition to assisting students in their understanding of the foundations of classical plasma physics, it provides a source of historic context for modern physicists. Highly successful upon its initial publication, this book was the standard text on plasma physics throughout the 1960s and 70s.Hailed by Science magazine as a ""well executed venture,"" the three-part treatment ranges from basic plasma theory to magnetohydrodynamics and microwa

  19. Team Danmarks støttekoncept

    Storm, Rasmus K.

    Evaluering af Team Danmarks støttekoncept 2005-2008 med omfattende analyser af Team Danmarks virke, dets støttekoncept og de samarbejdsrelationer med specialforbund, udøvere, politisk valgte ledere, trænere mv., som udmøntningen af støttekonceptet forudsætter. Herunder analyse af...

  20. Far infrared fusion plasma diagnostics

    Luhmann, N.C. Jr.; Peebles, W.A.


    Over the last several years, reflectometry has grown in importance as a diagnostic for both steady-state density Profiles as well as for the investigation of density fluctuations and turbulence. As a diagnostic for density profile measurement, it is generally believed to be well understood in the tokamak environment. However, its use as a fluctuation diagnostic is hampered by a lack of quantitative experimental understanding of its wavenumber sensitivity and spatial resolution. Several researchers, have theoretically investigated these questions. However, prior to the UCLA laboratory investigation, no group has experimentally investigated these questions. Because of the reflectometer's importance to the world effort in understanding plasma turbulence and transport, UCLA has, over the last year, made its primary Task IIIA effort the resolution of these questions. UCLA has taken the lead in a quantitative experimental understanding of reflectometer data as applied to the measurement of density fluctuations. In addition to this, work has proceeded on the design, construction, and installation of a reflectometer system on UCLA's CCT tokamak. This effort will allow a comparison between the improved confinement regimes (H-mode) observed on both the DIII-D and CCT machines with the goal of achieving a physics understanding of the phenomena. Preliminary investigation of a new diagnostic technique to measure density profiles as a function of time has been initiated at UCLA. The technique promises to be a valuable addition to the range of available plasma diagnostics. Work on advanced holographic reflectometry technique as applied to fluctuation diagnostics has awaited a better understanding of the reflectometer signal itself as discussed above. Efforts to ensure the transfer of the diagnostic developments have continued with particular attention devoted to the preliminary design of a multichannel FIR interferometer for MST.

  1. 78 FR 19632 - Special Local Regulations; St. Thomas Carnival Watersport Activities, Charlotte Amalie Harbor; St...


    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulations; St. Thomas Carnival... waters of Charlotte Amalie Harbor in St Thomas, USVI during the St. Thomas Carnival Watersport Activities... navigable waters of the United States during the St Thomas Carnival Watersport Activities. On April 21, 2013...

  2. Rapid Hydrophilization of Model Polyurethane/Urea (PURPEG Polymer Scaffolds Using Oxygen Plasma Treatment

    Rok Zaplotnik


    Full Text Available Polyurethane/urea copolymers based on poly(ethylene glycol (PURPEG were exposed to weakly ionized, highly reactive low-pressure oxygen plasma to improve their sorption kinetics. The plasma was sustained with an inductively coupled radiofrequency generator operating at various power levels in either E-mode (up to the forward power of 300 W or H-mode (above 500 W. The treatments that used H-mode caused nearly instant thermal degradation of the polymer samples. The density of the charged particles in E-mode was on the order of 1016 m−3, which prevented material destruction upon plasma treatment, but the density of neutral O-atoms in the ground state was on the order of 1021 m−3. The evolution of plasma characteristics during sample treatment in E-mode was determined by optical emission spectroscopy; surface modifications were determined by water adsorption kinetics and X-ray photoelectron spectroscopy; and etching intensity was determined by residual gas analysis. The results showed moderate surface functionalization with hydroxyl and carboxyl/ester groups, weak etching at a rate of several nm/s, rather slow activation down to a water contact angle of 30° and an ability to rapidly absorb water.

  3. ST Support for LHC Experiments

    Principe, R


    A couple of years ago, ST division created a first structure for the support of the LHC experiments, aiming to co-ordinate all the activities which traditionally were in the divisional mandate, like civil engineering, cooling and ventilation cranes and transports, electricity, etc. A picture of the last few months activity, mainly concentrated on the CMS experience, shows that synergies between project managers, personnel involved and group structures can strongly improve the service level in the specific divisional domains. A closer collaboration also seemed to facilitate the development of further opportunities tied to the competence available in the groups and of great interest to the experiments, like the participation of the design of the cooling system of several sub-detectors for the compact muon solenoid, as TK, EE, EB, SE, etc. The exponential increase of the demand confirms the divisional support as a real CERN need in this area, but also pushes ST to understand this dynamic environment and follow t...

  4. St. Lucia; Debt Sustainability Analysis

    International Monetary Fund


    This paper presents a debt sustainability analysis for St. Lucia. The medium-term scenario prepared by the IMF staff assumes continued fiscal consolidation and thus is compatible with sustainable debt levels even in the presence of adverse economic shocks. Stress tests show that stabilizing the debt/GDP ratio for the public sector at around the levels prevailing in 2002/03 would allow the absorption of economic shocks without generating unstable debt dynamics. Most temporary shocks would, how...

  5. Perturbative momentum transport in MAST L-mode plasmas

    Guttenfelder, W.; Field, A. R.; Lupelli, I.; Tala, T.; Kaye, S. M.; Ren, Y.; Solomon, W. M.


    Non-axisymmetric magnetic fields are used to perturbatively probe momentum transport physics in MAST L-mode plasmas. The low beta L-mode target was chosen to complement previous experiments conducted in high beta NSTX H-mode plasmas (β N  =  3.5-4.6) where an inward momentum pinch was measured. In those cases quasi-linear gyrokinetic simulations of unstable ballooning micro-instabilities predict weak or outward momentum convection, in contrast to the measurements. The weak pinch was predicted to be due to both electromagnetic effects at high beta and low aspect ratio minimizing the symmetry-breaking of the instabilities responsible for momentum transport. In an attempt to lessen these electromagnetic effects at low aspect ratio, perturbative experiments were run in MAST L-mode discharges at lower beta (β N  =  2). The perturbative transport analysis used the time-dependent response following the termination of applied 3D fields that briefly brake the plasma rotation (similar to the NSTX H-mode experiments). Assuming time-invariant diffusive (χ φ ) and convective (V φ ) transport coefficients, an inward pinch is inferred with magnitudes, (RV φ /χ φ )  =  (-1)-(-9), similar to those found in NSTX H-modes and in conventional tokamaks. However, if experimental uncertainties due to non-stationary conditions during and after the applied 3D field are considered, a weak pinch or even outward convection is inferred, (RV φ /χ φ )  =  (-1)-(+5). Linear gyrokinetic simulations indicate that for these lower beta L-modes, the predicted momentum pinch is predicted to be relatively small, (RV φ /χ φ )sim  ≈  -1. While this falls within the experimentally inferred range, the uncertainties are practically too large to quantitatively validate the predictions. Challenges and implications for this particular experimental technique are discussed, as well as additional possible physical mechanisms that may be important in

  6. Acute Coronary Syndrome and ST Segment Monitoring.

    Carey, Mary G


    Acute coronary syndrome (ACS) is caused by a critical obstruction of a coronary artery because of atherosclerotic coronary artery disease. Three specific conditions are included: ST elevation myocardial infarction, non-ST elevation myocardial infarction, and unstable angina. The ST segment on the electrocardiogram is a sensitive and specific marker of myocardial ischemia and infarction; however, ST segment deviation is regional not global, thus the ECG lead must be placed over the affected region of the myocardium. This article describes ACS and infarction and the use of ST segment monitoring to detect these conditions.

  7. Analysis of pedestal plasma transport

    Callen, J. D. [University of Wisconsin, Madison; Groebner, R. [General Atomics, San Diego; Osborne, T.H. [General Atomics, San Diego; Canik, John [ORNL; Owen, Larry W [ORNL; Pankin, A. Y. [Lehigh University, Bethlehem, PA; Rafiq, T. [Lehigh University, Bethlehem, PA; Rognlien, T. D. [Lawrence Livermore National Laboratory (LLNL); Stacey, W. M. [Georgia Institute of Technology


    An H-mode edge pedestal plasma transport benchmarking exercise was undertaken for a single DIII-D pedestal. Transport modelling codes used include 1.5D interpretive (ONETWO, GTEDGE), 1.5D predictive (ASTRA) and 2D ones (SOLPS, UEDGE). The particular DIII-D discharge considered is 98889, which has a typical low density pedestal. Profiles for the edge plasma are obtained from Thomson and charge-exchange recombination data averaged over the last 20% of the average 33.53 ms repetition time between type I edge localized modes. The modelled density of recycled neutrals is largest in the divertor X-point region and causes the edge plasma source rate to vary by a factor similar to 10(2) on the separatrix. Modelled poloidal variations in the densities and temperatures on flux surfaces are small on all flux surfaces up to within about 2.6 mm (rho(N) > 0.99) of the mid-plane separatrix. For the assumed Fick's-diffusion-type laws, the radial heat and density fluxes vary poloidally by factors of 2-3 in the pedestal region; they are largest on the outboard mid-plane where flux surfaces are compressed and local radial gradients are largest. Convective heat flows are found to be small fractions of the electron (less than or similar to 10%) and ion (less than or similar to 25%) heat flows in this pedestal. Appropriately averaging the transport fluxes yields interpretive 1.5D effective diffusivities that are smallest near the mid-point of the pedestal. Their 'transport barrier' minima are about 0.3 (electron heat), 0.15 (ion heat) and 0.035 (density) m(2) s(-1). Electron heat transport is found to be best characterized by electron-temperature-gradient-induced transport at the pedestal top and paleoclassical transport throughout the pedestal. The effective ion heat diffusivity in the pedestal has a different profile from the neoclassical prediction and may be smaller than it. The very small effective density diffusivity may be the result of an inward pinch flow nearly

  8. [St. John's wort: a pharmaceutical with potentially dangerous interactions].

    Rätz, A E; von Moos, M; Drewe, J


    Over-the-counter preparations of St. John's wort are widely used as 'natural' herbal medicine alternative to traditional antidepressants. The antidepressant effect has been shown in numerous placebo controlled studies. The mechanism of action is assumed to be at least in part, similar to conventional antidepressants, due to presynaptic serotonin reuptake inhibition as well as GABA-modulation and inhibition of monoaminoxidases. Because of its favorable safety profile compared to conventional antidepressants, the use of St. John's wort preparations has gained high acceptance with doctors and patients. However, any biologically active compound contains a certain risk of untoward effects and/or interactions which often are neither known nor recognised with the use of herbal remedies. Thus, doctors, pharmacists, and patients might feel themselves in false safety. Recently, a variety of case reports of potentially hazardous interactions due to drug combinations with St. John's wort have been published (e.g. cellular rejection of pancreas-, kidney- as well as heart transplants with ciclosporin therapy, rise of INR with oral anticoagulants, bleeding with oral contraceptives, reduction of plasma concentration of digoxin, indinavir, amitriptyline, and theophylline). We report a case of irregular bleeding with oral contraception and discuss these drug interactions and the mechanisms.

  9. JT-60U Thomson scattering system with multiple ruby laser and high spatial resolution for high electron temperature plasma measurement

    Yoshida, Hidetoshi; Naito, Osamu; Yamashita, Osamu; Kitamura, Shigeru; Hatae, Takaki; Nagashima, Akira [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment


    This article describes the design and operation of a 60 spatial channel Thomson scattering system as of 1996 with multiple ruby lasers to measure the electron temperature T{sub e} and density n{sub e} profiles of the JT-60U plasmas. The wide spectral range (403-683 nm) of the spectrometer and newly developed two-dimensional detector (high repetition photodiode array) has enabled this system to measure the high electron temperature plasma (5 keV or more) formed at the plasma core during negative magnetic shear discharge with high precision and reliability. The high spatial resolution (8 mm) have provided the precise measurement of steep electron temperature and density gradients formed at the plasma edge and in the scrape-off layer during H-mode discharge. The multilaser operation with the minimum time interval of 2 ms has provided an essential tool for the transient phenomenon measurement like the formation process of edge transport barrier during L- to H-mode transition and internal transport barrier during discharge with negative magnetic shear, the relaxation process of pellet injected plasma and so on. Measurement examples of recent JT-60U T{sub e} and n{sub e} profiles are also presented. (author)

  10. Plasma transport simulation modeling for helical confinement systems

    Yamazaki, K.; Amano, T.


    New empirical and theoretical transport models for helical confinement systems are developed based on the neoclassical transport theory including the effect of radial electric field and multi-helicity magnetic components, and the drift wave turbulence transport for electrostatic and electromagnetic modes, or the anomalous semi-empirical transport. These electron thermal diffusivities are compared with CHS (Compact Helical System) experimental data, which indicates that the central transport coefficient of the ECH plasma agrees with the neoclassical axi-symmetric value and the transport outside the half radius is anomalous. On the other hand, the transport of NBI-heated plasmas is anomalous in the whole plasma region. This anomaly is not explained by the electrostatic drift wave turbulence models in these flat-density-profile discharges. For the detailed prediction of plasma parameters in LHD (Large Helical Device), 3-D(dimensional) equilibrium/1-D transport simulations including empirical or drift wave turbulence models are carried out, which suggests that the global confinement time of LHD is determined mainly by the electron anomalous transport near the plasma edge region rather than the helical ripple transport in the core region. Even if the ripple loss can be eliminated, the increase of the global confinement is 10%. However, the rise in the central ion temperature is more than 20%. If the anomalous loss can be reduced to the half level of the present scaling, like so-called `H-mode` of the tokamak discharge, the neoclassical ripple loss through the ion channel becomes important even in the plasma core. The 5% radial inward shift of the plasma column with respect to the major radius is effective for improving plasma confinement and raising more than 50% of the fusion product by reducing this neoclassical asymmetric ion transport loss and increasing 10% in the plasma radius. (author).

  11. Plasma chromograninx

    Goetze, Jens P; Hilsted, Linda M; Rehfeld, Jens F


    Cardiovascular risk assessment remains difficult in elderly patients. We examined whether chromogranin A (CgA) measurement in plasma may be valuable in assessing risk of death in elderly patients with symptoms of heart failure in a primary care setting. A total of 470 patients (mean age 73 years......) were followed for 10 years. For CgA plasma measurement, we used a two-step method including a screening test and a confirmative test with plasma pre-treatment with trypsin. Cox multivariable proportional regression and receiver-operating curve (ROC) analyses were used to assess mortality risk...... of follow-up showed significant additive value of CgA confirm measurements compared with NT-proBNP and clinical variables. CgA measurement in the plasma of elderly patients with symptoms of heart failure can identify those at increased risk of short- and long-term mortality....

  12. Plasma Cleaning

    Hintze, Paul E.


    NASA's Kennedy Space Center has developed two solvent-free precision cleaning techniques: plasma cleaning and supercritical carbon dioxide (SCCO2), that has equal performance, cost parity, and no environmental liability, as compared to existing solvent cleaning methods.

  13. Optical Emission Spectroscopic Studies of ICP Ar Plasma

    QI Xuelian; REN Chunsheng; ZHANG Jian; MA Tengcai


    The ion line of 434.8 nm and atom line of 419.8 nm of Ar plasma produced by an inductively coupled plasma (ICP) were measured by optical emission spectroscopy and the influences from the working gas pressure, radio-frequency (RF) power and different positions in the discharge chamber on the line intensities were investigated in this study. It was found that the intensity of Ar atom line increased firstly and then saturated with the increase of the pressure. The line intensity of Ar+, on the other hand, reached a maximum value and then decreased along with the pressure. The intensity of the line in an RF discharge also demonstrated a jumping mode and a hysteresis phenomenon with the RF power. When the RF power increased to 400 W, the discharge jumped from the E-mode to the H-mode where the line intensity of Ar atom demonstrated a sudden increase, while the intensity of Ar+ ion only changed slightly. If the RF power decreased from a high value, e.g., 1000 W, the discharge would jump from the H-mode back to the E-mode at a power of 300 W. At this time the intensities of Ar and Ar+ lines would also decrease sharply. It was also noticed in this paper that the intensity of the ion line depended on the detective location in the chamber, namely at the bottom of the chamber the line was more intense than that in the middle of the chamber, but less intense than at the top, which is considered to be related to the capacitance coupling ability of the ICP plasma in different discharge areas.

  14. St. James Hospital. Lutcher, Louisiana

    Curtis & Davis, Arquitectos


    Full Text Available Un hospital debe estar proyectado, especialmente, para la comodidad y el cuidado de los enfermos. Atendiendo a este postulado, en el hospital St. James se ha buscado que los dormitorios se orienten al sur, y que desde ellos puedan apreciarse a través de amplias superficies acristaladas, la belleza del paisaje circundante. El gran ventanal corrido que compone la fachada meridional está protegido con parteluces giratorios verticales, que cada paciente puede abrir o cerrar a voluntad desde la misma cama.

  15. Plasma confinement

    Hazeltine, R D


    Detailed and authoritative, this volume examines the essential physics underlying international research in magnetic confinement fusion. It offers readable, thorough accounts of the fundamental concepts behind methods of confining plasma at or near thermonuclear conditions. Designed for a one- or two-semester graduate-level course in plasma physics, it also represents a valuable reference for professional physicists in controlled fusion and related disciplines.

  16. Attachment Instabilities of SF6 Inductively Coupled Plasmas under Different Coupling Intensities

    GAO Wei; SUN Bin; DING Zhen-Feng


    Characteristics of attachment instabilities in SF6 inductively coupled plasmas are experimentally studied under different coupling intensities.Experimental results show that the instabilities only occur in H modes operating in positive feedback regions.Both the sudden mode transitions and the instabilities are influenced by the coupling intensities.With increasing absorbed power,weak and middle coupling discharges can sequently undergo sudden mode transitions and attachment instabilities.In strong coupling discharges,the sudden mode transitions disappear and only attachment instabilities exist.The strong and weak coupling discharges are the most stable and unstable,respectively.

  17. St. John's wort - an overview.

    Linde, Klaus


    This article aims to summarize the current state of knowledge on St. John's wort (Hypericum perforatum L.) which is one of the oldest and best investigated medicinal herbs. Dried alcoholic extracts are the most important preparations on the market although a variety of other preparations are available. Depressive disorders according to modern diagnostic standards are the best known and most widely investigated indication although the more traditional, broader indication of 'psycho-vegetative disorders, depressive disorders, anxiety and/or nervous agitation', including diagnoses such as somatoform disorders, might more adequately describe what Hypericum extracts are actually used for by many practitioners. The exact mechanisms of action are still unclear, but the available research clearly shows that various bioactive constituents contribute to the clinical effects reported, often in a synergistic manner. Hypericum extracts have consistently shown activity in pharmacological models related to antidepressant effects. Randomized clinical trials show that Hypericum extracts are more effective than placebo and similarly effective as standard antidepressants while having better tolerability in the acute treatment of major depressive episodes. The most important risk associated with Hypericum extracts are interactions with other drugs. Therefore, physicians need to be informed whether their patients take St. John's wort products. If the risk of interactions is adequately taken into account, high quality Hypericum extracts are an effective and safe tool in the hand of qualified health profession-als in primary care.

  18. Støj fra installationer

    Kristensen, J.; Ovesen, K.

    Generende støj fra installationer er ikke noget nyt fænomen, men det er først i de senere år erkendt, at støj ikke er et naturfænomen, som beboerne bare skal finde sig i. De lovmæssige krav til bekæmpelse af støjproblemerne er af nyere dato og er endnu på mange områder ret ufuldkomne. Anvisningen...

  19. Soluble ST2 associates with diabetes but not established cardiovascular risk factors: a new inflammatory pathway of relevance to diabetes?

    Ashley M Miller

    Full Text Available Preliminary data mostly from animal models suggest the sST2/IL-33 pathway may have causal relevance for vascular disease and diabetes and thus point to a potential novel inflammatory link to cardiometabolic disease. However, the characterisation of sST2 levels in terms of metabolic or vascular risk in man is completely lacking. We sought to address this gap via a comprehensive analysis of risk factor and vascular correlates of sST2 in a cross-sectional study (pSoBid. We measured sST2 in plasma in 639 subjects and comprehensively related it to cardiovascular and diabetes risk factors and imaged atherosclerosis measures. Circulating sST2 levels increased with age, were lower in women and in highest earners. After adjusting for age and gender, sST2 levels associated strongly with markers of diabetes, including triglycerides [effect estimate (EE per 1 standard deviation increase in sST2:1.05 [95%CI 1.01,1.10], liver function (alanine aminotransaminase [ALT] and γ-glutamyl transferase [GGT]: EE 1.05 [1.01,1.09] and 1.13 [1.07,1.19] respectively, glucose (1.02 [1.00,1.03] and sICAM-1 (1.05 [1.02,1.07]. However, sST2 levels were not related to smoking, cholesterol, blood pressure, or atheroma (carotid intima media thickness, plaque presence. These results suggest that sST2 levels, in individuals largely without vascular disease, are related principally to markers associated with diabetes and ectopic fat and add support for a role of sST2 in diabetes. Further mechanistic studies determining how sST2 is linked to diabetes pathways may offer new insights into the inflammatory paradigm for type 2 diabetes.

  20. plasma treatment

    Puač Nevena


    Full Text Available In this paper we will present results for plasma sterilization of planktonic samples of two reference strains of bacteria, Pseudomonas aeruginosa ATCC 27853 and Enterococcus faecalis ATCC 29212. We have used a plasma needle as a source of non-equilibrium atmospheric plasma in all treatments. This device is already well characterized by OES, derivative probes and mass spectrometry. It was shown that power delivered to the plasma is bellow 2 W and that it produces the main radical oxygen and nitrogen species believed to be responsible for the sterilization process. Here we will only present results obtained by electron paramagnetic resonance which was used to detect the OH, H and NO species. Treatment time and power delivered to the plasma were found to have the strongest influence on sterilization. In all cases we have observed a reduction of several orders of magnitude in the concentration of bacteria and for the longest treatment time complete eradication. A more efficient sterilization was achieved in the case of gram negative bacteria.

  1. Plasma metallization

    Crowther, J M


    Many methods are currently used for the production of thin metal films. However, all of these have drawbacks associated with them, for example the need for UHV conditions, high temperatures, exotic metal precursors, or the inability to coat complex shaped objects. Reduction of supported metal salts by non-isothermal plasma treatment does not suffer from these drawbacks. In order to produce and analyse metal films before they become contaminated, a plasma chamber which could be attached directly to a UHV chamber with XPS capability was designed and built. This allowed plasma treatment of supported metal salts and surface analysis by XPS to be performed without exposure of the metal film to the atmosphere. Non-equilibrium plasma treatment of Nylon 66 supported gold(lll) chloride using hydrogen as the feed gas resulted in a 95% pure gold film, the remaining 5% of the film being carbon. If argon or helium were used as the feed gases during plasma treatment the resultant gold films were 100% pure. Some degree of s...

  2. [Comparative analysis of semiotic shifts, established by LCS of blood plasma from random samples of studied subjects from the zone of the Chernobyl accident, "Ural Radiation Trace", and collaborators from St. Petersburg Institute of Nuclear Physics of the Russian Academy of Sciences].

    Ternovoĭ, K S; Selezneva, T N; Akleev, A V; Pashkov, I A; Noskin, L A; Klopov, N V; Noskin, V A; Starodub, N F


    Using the developed "semiotic" classifier of laser correlation spectra of blood plasma the authors have carried out the verification of organism states of patients from the zone of Chernobyl accident, "Ural radiation trace" and collaborators from Sanct-Petersbourg Institute of Nuclear Physics. An analysis of results obtained using accidental selections which differed as to the character of radiation injury evidences for high informativeness of "semiotic" classifier of laser correlation spectra of blood plasma.

  3. Beam-Plasma Interaction in a 2D Complex Plasma

    Kyrkos, Stamatios; Kalman, G. J.; Rosenberg, M.


    In a complex (dusty) plasma, penetrating ion or electron beams may lead to beam-plasma instabilities. The instability displays interesting new properties when either the plasma or the beam, or both, are strongly interacting^1. Foremost amongst them is the possible generation of transverse instabilities. We consider the case when a 2D plasma is in the crystalline phase, forming a lattice, and the beam is moving in the lattice plane. Both the grains and the beam particles interact through a realistic Yukawa potential. The beam particles are assumed to be weakly coupled to each other and to the lattice^2. Using the full phonon spectrum for a 2D hexagonal Yukawa lattice^3, we determine and compare the transverse and longitudinal growth rates. The behavior of the growth rates depends on the direction of the beam and on the relationship between the beam speed v and the longitudinal and transverse sound speeds sL, sT. For beam speeds between the longitudinal and transverse sound speeds, the transverse instability could be more important, because it appears at lower k values. ^1 G. J. Kalman and M. Rosenberg, J. Phys. A: Math. Gen. 36 5963 (2003) ^2 M. Rosenberg, G. J. Kalman, S. Kyrkos and Z. Donko, J. Phys. A: Math. Gen. 39 4613 (2006) ^3 T. Sullivan, G. J. Kalman, S. Kyrkos, P. Bakshi, M. Rosenberg and Z. Donko, J. Phys. A: Math. Gen. 39 4607 (2006)

  4. Experimental investigation of vapor shielding effects induced by ELM-like pulsed plasma loads using the double plasma gun device

    Sakuma, I.; Kikuchi, Y.; Kitagawa, Y.; Asai, Y.; Onishi, K.; Fukumoto, N.; Nagata, M.


    We have developed a unique experimental device of so-called double plasma gun, which consists of two magnetized coaxial plasma gun (MCPG) devices, in order to clarify effects of vapor shielding on material erosion due to transient events in magnetically confined fusion devices. Two ELM-like pulsed plasmas produced by the two MCPG devices were injected into a target chamber with a variable time difference. For generating ablated plasmas in front of a target material, an aluminum foil sample in the target chamber was exposed to a pulsed plasma produced by the 1st MCPG device. The 2nd pulsed plasma was produced with a time delay of 70 μs. It was found that a surface absorbed energy measured by a calorimeter was reduced to ∼66% of that without the Al foil sample. Thus, the reduction of the incoming plasma energy by the vapor shielding effect was successfully demonstrated in the present experiment.

  5. Experimental investigation of vapor shielding effects induced by ELM-like pulsed plasma loads using the double plasma gun device

    Sakuma, I., E-mail:; Kikuchi, Y.; Kitagawa, Y.; Asai, Y.; Onishi, K.; Fukumoto, N.; Nagata, M.


    We have developed a unique experimental device of so-called double plasma gun, which consists of two magnetized coaxial plasma gun (MCPG) devices, in order to clarify effects of vapor shielding on material erosion due to transient events in magnetically confined fusion devices. Two ELM-like pulsed plasmas produced by the two MCPG devices were injected into a target chamber with a variable time difference. For generating ablated plasmas in front of a target material, an aluminum foil sample in the target chamber was exposed to a pulsed plasma produced by the 1st MCPG device. The 2nd pulsed plasma was produced with a time delay of 70 μs. It was found that a surface absorbed energy measured by a calorimeter was reduced to ∼66% of that without the Al foil sample. Thus, the reduction of the incoming plasma energy by the vapor shielding effect was successfully demonstrated in the present experiment.

  6. Regional Sediment Management Strategies for the Vicinity of St. Augustine Inlet, St. Johns County, Florida


    Ponte Vedra Beach and Vilano Beach, data indicate that it is best suited to beaches south of the inlet such as Anastasia Island and St. Augustine Beach...11 St. Johns County HSDR Feasibility Study: South Ponte Vedra Beach...feasibility study of potential additional segments of the overall St. Johns County SPP for nourishment, including South Ponte Vedra Beach and Vilano

  7. Plasma dynamo

    Rincon, F; Schekochihin, A A; Valentini, F


    Magnetic fields pervade the entire Universe and, through their dynamical interactions with matter, affect the formation and evolution of astrophysical systems from cosmological to planetary scales. How primordial cosmological seed fields arose and were further amplified to $\\mu$Gauss levels reported in nearby galaxy clusters, near equipartition with kinetic energy of plasma motions and on scales of at least tens of kiloparsecs, is a major theoretical puzzle still largely unconstrained by observations. Extragalactic plasmas are weakly collisional (as opposed to collisional magnetohydrodynamic fluids), and whether magnetic-field growth and its sustainment through an efficient dynamo instability driven by chaotic motions is possible in such plasmas is not known. Fully kinetic numerical simulations of the Vlasov equation in a six-dimensional phase space necessary to answer this question have until recently remained beyond computational capabilities. Here, we show by means of such simulations that magnetic-field a...

  8. Investigation of instabilities and rotation alteration in high beta KSTAR plasmas

    Park, Y. S.; Sabbagh, S. A.; Ko, W. H.; Bak, J. G.; Berkery, J. W.; Bialek, J. M.; Choi, M. J.; Hahn, S. H.; In, Y. K.; Jardin, S. C.; Jeon, Y. M.; Kim, J.; Kwak, J. G.; Lee, S. G.; Oh, Y. K.; Park, H. K.; Yoon, S. W.; Yun, G. S.


    H-mode plasma operation of the Korea Superconducting Tokamak Advanced Research (KSTAR) device has been expanded to significantly surpass the ideal MHD no-wall beta limit. Plasmas with high normalized beta, βN, up to 4.3 have been achieved with reduced plasma internal inductance, li, to near 0.7, exceeding the computed n = 1 ideal no-wall limit by a factor of 1.6. Pulse lengths at maximum βN were extended to longer pulses by new, more rapid control. The stability of the observed m/n = 2/1 tearing mode that limited the achieved high βN is computed by the M3D-C1 code, and the effect of sheared toroidal rotation to tearing stability is examined. As a method to affect the mode stability in high βN plasmas, the non-resonant alteration of the rotation profile by non-axisymmetric magnetic fields has been used, enabling a study of the underlying neoclassical toroidal viscosity (NTV) physics and stability dependence on rotation. Non-axisymmetric field spectra were applied using in-vessel control coils (IVCCs) with varied n = 2 field configurations to alter the plasma toroidal rotation profile in high beta H-mode plasmas and to analyze their effects on the rotation. The rotation profile was significantly altered with rotation reduced by more than 60% without tearing activity or mode locking. To investigate the physical characteristics and scaling of the measured rotation braking by NTV, changes in the rotation profile are analytically examined in steady state. The expected NTV scaling with the square of the normalized applied field perturbation agrees with the measured profile change δB2.1-2.3. The NTV is also found to scale as Ti2.1-2.4, in general agreement with the low collisionality "1/ν" regime scaling of the NTV theory (TNTV-(1/ν) ∝ Ti2.5).

  9. Sensitivity of injected argon behavior to changes in magnetic balance in double-null plasmas in DIII-D

    Petrie, T.W. [General Atomics, P.O. Box 85608, San Diego, CA 92186-5608 (United States)], E-mail:; Brooks, N.H. [General Atomics, P.O. Box 85608, San Diego, CA 92186-5608 (United States); Fenstermacher, M.E.; Groth, M. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551 (United States); Hyatt, A.W. [General Atomics, P.O. Box 85608, San Diego, CA 92186-5608 (United States); Lasnier, C.J. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551 (United States); Leonard, A.W. [General Atomics, P.O. Box 85608, San Diego, CA 92186-5608 (United States); Porter, G.D. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551 (United States); Schaffer, M.J.; Wade, M.R. [General Atomics, P.O. Box 85608, San Diego, CA 92186-5608 (United States); Watkins, J.G. [Sandia National Laboratories, P.O. Box 5800, Albuquerque, NM 87185 (United States); West, W.P. [General Atomics, P.O. Box 85608, San Diego, CA 92186-5608 (United States)


    Recent DIII-D experiments show that both magnetic balance and particle drifts are important to understanding how argon impurities accumulate in balanced and unbalanced double-null plasmas during 'puff and pump' radiating divertor operation. Unbalanced double-null shapes, which are biased in the direction opposite to the ion Bx{nabla}B drift direction, have produced the best result to-date in terms of coupling a radiating divertor approach with an H-mode plasma. The proximity to balanced double-null that can be used for puff-and-pump may depend on the width of the heat flux profile in the scrape-off layer. A comparison of plasma behavior in the open lower divertor to that of the more closed upper divertor determined that plasma density control was far more sensitive to the ion Bx{nabla}B drift direction than to the relative closure of the divertor.

  10. The role of the st313-td gene in virulence of Salmonella Typhimurium ST313.

    Ana Herrero-Fresno

    Full Text Available Multidrug-resistant Salmonella enterica serovar Typhimurium ST313 has emerged in sub-Saharan Africa causing severe infections in humans. Therefore, it has been speculated that this specific sequence type, ST313, carries factors associated with increased pathogenicity. We assessed the role in virulence of a gene with a yet unknown function, st313-td, detected in ST313 through comparative genomics. Additionally, the structure of the genomic island ST313-GI, harbouring the gene was determined. The gene st313-td was cloned into wild type S. Typhimurium 4/74 (4/74-C as well as knocked out in S. Typhimurium ST313 02-03/002 (Δst313-td followed by complementation (02-03/002-C. Δst313-td was less virulent in mice following i.p. challenge than the wild type and this phenotype could be partly complemented in trans, indicating that st313-td plays a role during systemic infection. The gene st313-td was shown not to affect invasion of cultured epithelial cells, while the absence of the gene significantly affects uptake and intracellular survival within macrophages. The gene st313-td was proven to be strongly associated to invasiveness, harboured by 92.5% of S. Typhimurium blood isolates (n = 82 and 100% of S. Dublin strains (n = 50 analysed. On the contrary, S. Typhimurium isolates of animal and food origin (n = 82 did not carry st313-td. Six human, non-blood isolates of S. Typhimurium from Belarus, China and Nepal harboured the gene and belonged to sequence types ST398 and ST19. Our data showed a global presence of the st313-td gene and in other sequence types than ST313. The gene st313-td was shown to be expressed during logarithmic phase of growth in 14 selected Salmonella strains carrying the gene. This study reveals that st313-td plays a role in S. Typhimurium ST313 pathogenesis and adds another chapter to understanding of the virulence of S. Typhimurium and in particular of the emerging sequence type ST313.

  11. 21st International Meshing Roundtable

    Weill, Jean-Christophe


    This volume contains the articles presented at the 21st International Meshing Roundtable (IMR) organized, in part, by Sandia National Laboratories and was held on October 7–10, 2012 in San Jose, CA, USA. The first IMR was held in 1992, and the conference series has been held annually since. Each year the IMR brings together researchers, developers, and application experts in a variety of disciplines, from all over the world, to present and discuss ideas on mesh generation and related topics. The technical papers in this volume present theoretical and novel ideas and algorithms with practical potential, as well as technical applications in science and engineering, geometric modeling, computer graphics, and visualization.

  12. Plasma medicine

    Fridman, Alexander


    This comprehensive text is suitable for researchers and graduate students of a 'hot' new topic in medical physics. Written by the world's leading experts,  this book aims to present recent developments in plasma medicine, both technological and scientific, reviewed in a fashion accessible to the highly interdisciplinary audience consisting of doctors, physicists, biologists, chemists and other scientists, university students and professors, engineers and medical practitioners. The book focuses on major topics and covers the physics required to develop novel plasma discharges relevant for medic

  13. Non ST-elevation acute coronary syndrome

    Sarkees, Michael L; Bavry, Anthony A.


    Non ST-elevation acute coronary syndrome (NSTE-ACS, here defined as unstable angina and non ST-elevation MI) is characterised by episodes of chest pain at rest or with minimal exertion, which increase in frequency or severity, often with dynamic ECG changes.

  14. Firmaets Største Bedrift

    Hansen, Peer Henrik

    fortæller, hvordan de tidligere modstandsfolk Arne Sejr og Niels Frommelt få år efter befrielsen etablerede deres såkaldte Firma for med støtte fra ledende danske politikere, Forsvarets Efterretningstjeneste og CIA at organisere en hemmelig krig mod Sovjetunionens danske støtter. Meget tyder på, at både...

  15. 21st Century Skills Map: The Arts

    Dean, Colleen; Ebert, Christie M. Lynch; McGreevy-Nichols, Susan; Quinn, Betsy; Sabol, F. Robert; Schmid, Dale; Shauck, R. Barry; Shuler, Scott C.


    This 21st Century Skills Map is the result of hundreds of hours of research, development and feedback from educators and business leaders across the nation. The Partnership for 21st Century Skills has issued this map for the core subject of the Arts.

  16. St. John's Wort (Hypericum Perforatum) and Pregnancy

    ... best live chat Live Help Fact Sheets Share St. John’s Wort (Hypericum perforatum) Friday, 01 May 2015 In every pregnancy, ... risk. This sheet talks about whether exposure to St. John’s Wort may increase the risk for birth defects over ...

  17. RF wave propagation and scattering in turbulent tokamak plasmas

    Horton, W., E-mail:; Michoski, C. [Institute for Fusion Studies, The University of Texas at Austin, Austin, TX 78654 (United States); Peysson, Y.; Decker, J. [CEA, IRFM, 13108, Saint-Paul, Durance Cedex (France)


    Drift wave turbulence driven by the steep electron and ion temperature gradients in H-mode divertor tokamaks produce scattering of the RF waves used for heating and current drive. The X-ray emission spectra produced by the fast electrons require the turbulence broaden RF wave spectrum. Both the 5 GHz Lower Hybrid waves and the 170 GHz electron cyclotron [EC] RF waves experience scattering and diffraction by the electron density fluctuations. With strong LHCD there are bifurcations in the coupled turbulent transport dynamics giving improved steady-state confinement states. The stochastic scattering of the RF rays makes the prediction of the distribution of the rays and the associated particle heating a statistical problem. Thus, we introduce a Fokker-Planck equation for the probably density of the RF rays. The general frame work of the coupled system of coupled high frequency current driving rays with the low-frequency turbulent transport determines the profiles of the plasma density and temperatures.

  18. Plasma physics and engineering

    Fridman, Alexander


    Part I: Fundamentals of Plasma Physics and Plasma ChemistryPlasma in Nature, in the Laboratory, and in IndustryOccurrence of Plasma: Natural and Man MadeGas DischargesPlasma Applications, Plasmas in IndustryPlasma Applications for Environmental ControlPlasma Applications in Energy ConversionPlasma Application for Material ProcessingBreakthrough Plasma Applications in Modern TechnologyElementary Processes of Charged Species in PlasmaElementary Charged Particles in Plasma and Their Elastic and Inelastic CollisionsIonization ProcessesMechanisms of Electron Losses: The Electron-Ion RecombinationEl

  19. Progress toward commissioning and plasma operation in NSTX-U

    Ono, M.; Chrzanowski, J.; Dudek, L.; Gerhardt, S.; Heitzenroeder, P.; Kaita, R.; Menard, J. E.; Perry, E.; Stevenson, T.; Strykowsky, R.; Titus, P.; von Halle, A.; Williams, M.; Atnafu, N. D.; Blanchard, W.; Cropper, M.; Diallo, A.; Gates, D. A.; Ellis, R.; Erickson, K.; Hosea, J.; Hatcher, R.; Jurczynski, S. Z.; Kaye, S.; Labik, G.; Lawson, J.; LeBlanc, B.; Maingi, R.; Neumeyer, C.; Raman, R.; Raftopoulos, S.; Ramakrishnan, R.; Roquemore, A. L.; Sabbagh, S. A.; Sichta, P.; Schneider, H.; Smith, M.; Stratton, B.; Soukhanovskii, V.; Taylor, G.; Tresemer, K.; Zolfaghari, A.; The NSTX-U Team


    The National Spherical Torus Experiment-Upgrade (NSTX-U) is the most powerful spherical torus facility at PPPL, Princeton USA. The major mission of NSTX-U is to develop the physics basis for an ST-based Fusion Nuclear Science Facility (FNSF). The ST-based FNSF has the promise of achieving the high neutron fluence needed for reactor component testing with relatively modest tritium consumption. At the same time, the unique operating regimes of NSTX-U can contribute to several important issues in the physics of burning plasmas to optimize the performance of ITER. NSTX-U further aims to determine the attractiveness of the compact ST for addressing key research needs on the path toward a fusion demonstration power plant (DEMO). The upgrade will nearly double the toroidal magnetic field BT to 1 T at a major radius of R0 = 0.93 m, plasma current Ip to 2 MA and neutral beam injection (NBI) heating power to 14 MW. The anticipated plasma performance enhancement is a quadrupling of the plasma stored energy and near doubling of the plasma confinement time, which would result in a 5-10 fold increase in the fusion performance parameter nτ T. A much more tangential 2nd NBI system, with 2-3 times higher current drive efficiency compared to the 1st NBI system, is installed to attain the 100% non-inductive operation needed for a compact FNSF design. With higher fields and heating powers, the NSTX-U plasma collisionality will be reduced by a factor of 3-6 to help explore the favourable trend in transport towards the low collisionality FNSF regime. The NSTX-U first plasma is planned for the Summer of 2015, at which time the transition to plasma operations will occur.

  20. Opening Switch Research on a Plasma Focus VI.


    densi y ( -’cm-3 suggest that th. I asma is at max imu: compress ion. Xna xxmmn1m AVI JulmrW0 51 (a) PLASMA DENSITY (SCALE: 1.0=1.6- 1018CM-3 ) 1.0 .4 7...IEEE inter. Pulsed Power Conf., New Mexico , 350 (1983). 3. F. Venneri, and G. Gerdin, IEEE Int. Conf. on Plasma Sci., St. Louis, MO, 1984, Conf. Record

  1. Initial measurements of plasma current and electron density profiles using a polarimeter/interferometer (POINT) for long pulse operation in EAST (invited)

    Liu, H. Q.; Qian, J. P.; Jie, Y. X.; Ding, W. X.; Brower, D. L.; Zou, Z. Y.; Li, W. M.; Lian, H.; Wang, S. X.; Yang, Y.; Zeng, L.; Lan, T.; Yao, Y.; Hu, L. Q.; Zhang, X. D.; Wan, B. N.


    A double-pass, radially viewing, far-infrared laser-based POlarimeter-INTerferometer (POINT) system utilizing the three-wave technique has been implemented for diagnosing the plasma current and electron density profiles in the Experimental Advanced Superconducting Tokamak (EAST). POINT has been operated routinely during the most recent experimental campaign and provides continuous 11 chord line-integrated Faraday effect and density measurement throughout the entire plasma discharge for all heating schemes and all plasma conditions (including ITER relevant scenario development). Reliability of both the polarimetric and interferometric measurements is demonstrated in 25 s plasmas with H-mode and 102 s long-pulse discharges. Current density, safety factor (q), and electron density profiles are reconstructed using equilibrium fitting code (EFIT) with POINT constraints for the plasma core.

  2. Galleria mellonella infection model demonstrates high lethality of ST69 and ST127 uropathogenic E. coli.

    Majed F Alghoribi

    Full Text Available Galleria mellonella larvae are an alternative in vivo model for investigating bacterial pathogenicity. Here, we examined the pathogenicity of 71 isolates from five leading uropathogenic E. coli (UPEC lineages using G. mellonella larvae. Larvae were challenged with a range of inoculum doses to determine the 50% lethal dose (LD50 and for analysis of survival outcome using Kaplan-Meier plots. Virulence was correlated with carriage of a panel of 29 virulence factors (VF. Larvae inoculated with ST69 and ST127 isolates (10(4 colony-forming units/larvae showed significantly higher mortality rates than those infected with ST73, ST95 and ST131 isolates, killing 50% of the larvae within 24 hours. Interestingly, ST131 isolates were the least virulent. We observed that ST127 isolates are significantly associated with a higher VF-score than isolates of all other STs tested (P≤0.0001, including ST69 (P<0.02, but one ST127 isolate (strain EC18 was avirulent. Comparative genomic analyses with virulent ST127 strains revealed an IS1 mediated deletion in the O-antigen cluster in strain EC18, which is likely to explain the lack of virulence in the larvae infection model. Virulence in the larvae was not correlated with serotype or phylogenetic group. This study illustrates that G. mellonella are an excellent tool for investigation of the virulence of UPEC strains. The findings also support our suggestion that the incidence of ST127 strains should be monitored, as these isolates have not yet been widely reported, but they clearly have a pathogenic potential greater than that of more widely recognised clones, including ST73, ST95 or ST131.

  3. The relation between electrocardiographic ST-T changes and NT-proBNP in patients with acute ischemic stroke

    Jensen, Jesper K; Korsholm, Lars; Høilund-Carlsen, Poul Flemming


    BACKGROUND: ST-segment depression and T-wave inversion (ST-T changes) in the electrocardiogram (ECG) and raised levels of natriuretic peptide have been observed in acute ischemic stroke patients. It is unknown whether any relation between ST-T changes and raised levels of natriuretic peptides...... in patients with an acute ischemic stroke exists. METHODS: Serial measurements of plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) and 12-lead ECGs were obtained in 192 consecutive patients with an acute ischemic stroke without ischemic heart disease, atrial fibrillation, heart- or renal failure......-T changes in the ECG remained associated with increased levels of NT-proBNP (beta=76.5, p=0.011). CONCLUSIONS: ST-T changes suggestive of myocardial ischemia are independently associated with the levels of NT-proBNP in patients with acute ischemic stroke. The clinical importance of this observation remains...

  4. Magnetoresistive waves in plasmas

    Felber, F. S.; Hunter, R. O., Jr.; Pereira, N. R.; Tajima, T.


    The self-generated magnetic field of a current diffusing into a plasma between conductors can magnetically insulate the plasma. Propagation of magnetoresistive waves in plasmas is analyzed. Applications to plasma opening switches are discussed.

  5. Does St. John's Wort cause regression in gastrointestinal system adenocarcinomas?

    Karaarslan, Serap; Cokmert, Suna; Cokmez, Atilla


    St. John's Wort (SJW) is an old herb which has long been consumed widely for its anti-inflammatory, antiviral, and anti-depressive properties. Here we present a detailed clinical evaluation of three cases (two colon and one duodenal adenocarcinoma) with remarkable and intensive lymphoplasmocytic host reaction, at the basal part of tumor, intensive fibrosis, giant cells, plasma cell increase in lymph nodes and few giant cells in germinal centers in resection specimens. The observation of similar host reaction in those tumors having otherwise usual appearance was interesting. None of the cases received neoadjuvant chemoradiotherapy or additional treatment before surgery but only SJW. These cases are presented to increase the awareness about such cases. Further research is needed to reveal the possible effect of SJW, which has long been consumed for different treatment purposes, on human tumors.

  6. Mammalian gamete plasma membranes re-assessments and reproductive implications

    Establishment of the diploid status occurs with the fusion of female and male gametes. Both the mammalian oocyte and spermatozoa are haploid cells surrounded with plasma membranes that are rich in various proteins playing a crucial role during fertilization. Fertilization is a complex and ordered st...

  7. Electrosurgical plasmas

    Stalder, Kenneth R.; McMillen, Donald F.; Woloszko, Jean


    Electrosurgical medical devices based on repetitively pulsed nonequilibrium micron-scale to millimetre-scale plasma discharges in saline solutions are described. The formation of vapour layers (bubbles) around active electrodes appears to be a common feature at moderate (<300 V rms) voltages, and dissociation, excitation and ionization of the vapour in these bubbles produces chemical conditions that are thought to be the source of beneficial tissue removal and treatment. Experimental data are discussed, as are the results of modelling efforts of the plasma chemistry. Hydroxyl radicals, hydrogen atoms and other species are observed spectroscopically and their interactions with collagen, a common component of tissue encountered in surgical situations, are considered. Several pathways by which hydroxyl radicals interacting with collagen can lead to tissue removal are discussed.

  8. Electrosurgical plasmas

    Stalder, Kenneth R; McMillen, Donald F; Woloszko, Jean [ArthroCare Corp., Sunnyvale, CA 94085-3523 (United States)


    Electrosurgical medical devices based on repetitively pulsed nonequilibrium micron-scale to millimetre-scale plasma discharges in saline solutions are described. The formation of vapour layers (bubbles) around active electrodes appears to be a common feature at moderate (<300 V rms) voltages, and dissociation, excitation and ionization of the vapour in these bubbles produces chemical conditions that are thought to be the source of beneficial tissue removal and treatment. Experimental data are discussed, as are the results of modelling efforts of the plasma chemistry. Hydroxyl radicals, hydrogen atoms and other species are observed spectroscopically and their interactions with collagen, a common component of tissue encountered in surgical situations, are considered. Several pathways by which hydroxyl radicals interacting with collagen can lead to tissue removal are discussed.

  9. St2-80: a new FISH marker for St genome and genome analysis in Triticeae.

    Wang, Long; Shi, Qinghua; Su, Handong; Wang, Yi; Sha, Lina; Fan, Xing; Kang, Houyang; Zhang, Haiqin; Zhou, Yonghong


    The St genome is one of the most fundamental genomes in Triticeae. Repetitive sequences are widely used to distinguish different genomes or species. The primary objectives of this study were to (i) screen a new sequence that could easily distinguish the chromosome of the St genome from those of other genomes by fluorescence in situ hybridization (FISH) and (ii) investigate the genome constitution of some species that remain uncertain and controversial. We used degenerated oligonucleotide primer PCR (Dop-PCR), Dot-blot, and FISH to screen for a new marker of the St genome and to test the efficiency of this marker in the detection of the St chromosome at different ploidy levels. Signals produced by a new FISH marker (denoted St2-80) were present on the entire arm of chromosomes of the St genome, except in the centromeric region. On the contrary, St2-80 signals were present in the terminal region of chromosomes of the E, H, P, and Y genomes. No signal was detected in the A and B genomes, and only weak signals were detected in the terminal region of chromosomes of the D genome. St2-80 signals were obvious and stable in chromosomes of different genomes, whether diploid or polyploid. Therefore, St2-80 is a potential and useful FISH marker that can be used to distinguish the St genome from those of other genomes in Triticeae.

  10. International S&T Engagement Strategy


    the DOD’s science and technology (S&T) and internationa l communities. Our offices, OASD(R&E) and OUSD(A T &L)/IC, have worked together to deve lop engagement. Specifica lly, it is important to deve lop robust measures of success and maturity in priority S&T areas, and identify and address...Develop a baseline of relevant global S&T concepts, existing and emerging technologies, and capabilities. o Deve lop an understanding of the g loba l

  11. Plasma physics

    Cairns, R A


    This book is intended as an introduction to plasma physics at a level suitable for advanced undergraduates or beginning postgraduate students in physics, applied mathematics or astrophysics. The main prerequisite is a knowledge of electromagnetism and of the associated mathematics of vector calculus. SI units are used throughout. There is still a tendency amongst some plasma physics researchers to· cling to C.g.S. units, but it is the author's view that universal adoption of SI units, which have been the internationally agreed standard since 1960, is to be encouraged. After a short introductory chapter, the basic properties of a plasma con­ cerning particle orbits, fluid theory, Coulomb collisions and waves are set out in Chapters 2-5, with illustrations drawn from problems in nuclear fusion research and space physics. The emphasis is on the essential physics involved and (he theoretical and mathematical approach has been kept as simple and intuitive as possible. An attempt has been made to draw attention t...

  12. Plasma pharmacy - physical plasma in pharmaceutical applications.

    von Woedtke, Th; Haertel, B; Weltmann, K-D; Lindequist, U


    During the last years the use of physical plasma for medical applications has grown rapidly. A multitude of findings about plasma-cell and plasma-tissue interactions and its possible use in therapy have been provided. One of the key findings of plasma medical basic research is that several biological effects do not result from direct plasma-cell or plasma-tissue interaction but are mediated by liquids. Above all, it was demonstrated that simple liquids like water or physiological saline, are antimicrobially active after treatment by atmospheric pressure plasma and that these effects are attributable to the generation of different low-molecular reactive species. Besides, it could be shown that plasma treatment leads to the stimulation of specific aspects of cell metabolism and to a transient and reversible increase of diffusion properties of biological barriers. All these results gave rise to think about another new and innovative field of medical plasma application. In contrast to plasma medicine, which means the direct use of plasmas on or in the living organism for direct therapeutic purposes, this field - as a specific field of medical plasma application - is called plasma pharmacy. Based on the present state of knowledge, most promising application fields of plasma pharmacy might be: plasma-based generation of biologically active liquids; plasma-based preparation, optimization, or stabilization of - mainly liquid - pharmaceutical preparations; support of drug transport across biological barriers; plasma-based stimulation of biotechnological processes.

  13. Fusion programs in applied plasma physics


    The objectives of the theoretical science program are: To support the interpretation of present experiments and predict the outcome of future planned experiments; to improve on existing models and codes and validate against experimental results; and to conduct theoretical physics development of advanced concepts with applications for DIII-D and future devices. Major accomplishments in FY91 include the corroboration between theory and experiment on MHD behavior in the second stable regime of operation on DIII-D, and the frequency and mode structure of toroidal Alfven eigenmodes in high beta, shaped plasmas. We have made significant advances in the development of the gyro-Landau fluid approach to turbulence simulation which more accurately models kinetic drive and damping mechanisms. Several theoretical models to explain the bifurcation phenomenon in L- to H-mode transition were proposed providing the theoretical basis for future experimental verification. The capabilities of new rf codes have been upgraded in response to the expanding needs of the rf experiments. Codes are being employed to plan for a fully non-inductive current drive experiment in a high beta, enhanced confinement regime. GA's experimental effort in Applied Physics encompasses two advanced diagnostics essential for the operation of future fusion experiments: Alpha particle diagnostic, and current and density profile diagnostics. This paper discusses research in all these topics.

  14. Science diplomacy in the 21st century.

    Fedoroff, Nina V


    Science diplomacy is the use of scientific collaborations among nations to address the common problems facing 21(st) century humanity and to build constructive international partnerships. There are many ways that scientists can contribute to this process.

  15. Hunting Plan: St. Vincent National Wildlife Refuge

    US Fish and Wildlife Service, Department of the Interior — This plan provides guidelines for the administration of hunting activity and for the development, maintenance, and enforcement of regulations and guidelines on St....

  16. 2008 St. Johns County, FL Countywide Lidar

    National Oceanic and Atmospheric Administration, Department of Commerce — Airborne terrestrial LiDAR was collected for St. Johns County, FL. System Parameters/Flight Plan. The LiDAR system acquisition parameters were developed based on a...

  17. Inventory Plan : St. Vincent National Wildlife Refuge

    US Fish and Wildlife Service, Department of the Interior — The inventory procedures outlined in this plan represent a cost effective inventory of the wildlife populations on St. Vincent National Wildlife Refuge. Winter...

  18. Location - Managed Facility - St. Paul District (MVP)

    Army Corps of Engineers, Department of the Army, Department of Defense — St. Paul District - US Army Corps of Engineers Managed Facility locations. District headquarters, Natural Resource, Recreation, Lock and Dam, and Regulatory offices...

  19. St. John Shallow Water Accuracy Assessment Transects

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic habitat maps of the nearshore marine environment of St. John, U.S. Virgin Islands were created by visual interpretation of remotely sensed imagery. The...

  20. St. Vincent National Wildlife Refuge Historical Photographs

    US Fish and Wildlife Service, Department of the Interior — This document contains a series of photographs from St. Vincent Island. Photograph dates range from 1909 to 1969. Subjects include structures, vegetation, equipment,...

  1. St. Vincent National Wildlife Refuge : Plant Database

    US Fish and Wildlife Service, Department of the Interior — This is the plant database for St. Vincent National Wildlife Refuge. The database is a compilation of published lists of plants for the refuge as well as site...

  2. A Monograph on St. Vincent's Game Preserve

    US Fish and Wildlife Service, Department of the Interior — This document describes the geography, history, climate, and wildlife of St. Vincent’s Game Preserve. Photographs, maps, articles, and letters are included.

  3. Natural History of St. Vincent Island, Florida

    US Fish and Wildlife Service, Department of the Interior — A study proposal aiming to ascertain, list and describe the woody flora and vertebrate fauna of St. Vincent Island, and to describe the terrestrial and fresh water...

  4. 2004 St. Johns County, Florida Lidar

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset is the bare earth lidar data for St. Johns County, Florida, acquired in early January and February of 2004. This data was collected to develop...

  5. ST elevation occurring during stress testing

    Diana Malouf


    Full Text Available A case is presented of significant reversible ST elevation occurring during treadmill testing, and the coronary anatomy and subsequent course are described, indicating that ischemia is a potential cause of this electrocardiographic finding.

  6. Control Strategy Tool (CoST)

    U.S. Environmental Protection Agency — The EPA Control Strategy Tool (CoST) is a software tool for projecting potential future control scenarios, their effects on emissions and estimated costs. This tool...

  7. 2004 St. Johns County, Florida Lidar

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset is the bare earth lidar data for St. Johns County, Florida, acquired in early January and February of 2004. This data was collected to develop...

  8. St. Vincent Offers Special Archery & Primitive Hunts

    US Fish and Wildlife Service, Department of the Interior — St. Vincent National Wildlife Refuge's archery hunt is scheduled for November 28-30, 1984. White-tailed deer, turkeys, and hogs may be taken.

  9. Caribbean ST Croix Logbook Survey (Vessels)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains catch (landed catch) and effort for fishing trips made by vessels fishing in St. Croix. The catch and effort data for the entire trip are...

  10. Caribbean ST Thomas trap Logbook Survey (Vessels)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains catch (landed catch) and effort for fishing trips made by vessels fishing in St. Thomas. The catch and effort data for the entire trip are...

  11. Specification For ST-5 Li Ion Battery

    Castell, Karen D.; Day, John H. (Technical Monitor)


    This Specification defines the general requirements for rechargeable Space Flight batteries intended for use in the ST-5 program. The battery chemistry chosen for this mission is lithium ion (Li-Ion).

  12. Effect of St. John's wort supplementation on the pharmacokinetics of bupropion in healthy male Chinese volunteers.

    Lei, H-P; Yu, X-Y; Xie, H-T; Li, H-H; Fan, L; Dai, L-L; Chen, Y; Zhou, H-H


    The objective of this study was to investigate the effects of continuous St. John's wort administration on single-dose pharmacokinetics of bupropion, a substrate of cytochrome P450 (CYP) 2B6, in healthy Chinese volunteers. Eighteen unrelated healthy male subjects participated in this study. The single-dose pharmacokinetics of bupropion and hydroxybupropion were determined before (control) and after a long-term period of St. John's wort intake (325 mg, three times a day for 14 days). Plasma concentrations of bupropion and hydroxybupropion were determined before and at 0.5, 1, 2, 3, 4, 5, 6, 8, 10, 12, 24, 36, 48, 60 and 72 h after dosing. St. John's wort treatment decreased the area under the concentration versus time curve extrapolated to infinity of bupropion in healthy volunteers from 1.4 microg.h ml(-1) (95% confidence interval [CI] = 1.2-1.6 microg.h ml(-1)) after bupropion alone to 1.2 microg.h ml(-1) (95% CI = 1.1-1.3 microg.h ml(-1)) during St. John's wort treatment. St. John's wort treatment increased the oral clearance of bupropion from 108.3 l h(-1) (95% CI = 95.4-123.0 l h(-1)) to 130.0 l h(-1) (95% CI = 118.4-142.7 l h(-1)). No change in the time to peak concentration (t(max)) and the blood elimination half-life (t(1/2)) of bupropion was observed between the control and St. John's wort-treated phases. However, the half-life of hydroxybupropion between two phases had a significant difference by a Student's t test after logarithmic transformation. St. John's wort treatment decreased the half-life of hydroxybupropion from 26.7 h (95% CI = 23.8-29.9 h) to 24.4 h (95% CI = 21.9-27.3 h). St. John's wort decreased, to a statistically significant extent, the plasma concentrations of bupropion, probably mainly by increasing the clearance of bupropion.

  13. A nosocomial outbreak of KPC-2-producing Klebsiella pneumoniae in a Chinese hospital: dissemination of ST11 and emergence of ST37, ST392 and ST395.

    Yang, J; Ye, L; Guo, L; Zhao, Q; Chen, R; Luo, Y; Chen, Y; Tian, S; Zhao, J; Shen, D; Han, L


    In China, Klebsiella pneumoniae carbapenemase (KPC) -producing K. pneumoniae isolates have been identified. However, little is known about the spread and outbreak of KPC-producing enterobacterial pathogens. In this study, 48 non-duplicated KPC-producing isolates were analysed for genetic relatedness by pulsed-field gel electrophoresis (PFGE), antimicrobial susceptibility by E-test, and sequence type (ST) by multilocus sequence typing. S1-PFGE and Southern blot were used for plasmid profiling, and PCR and subsequent sequencing were performed to determine the effects of genetic background on the blaKPC gene. From December 2011 to June 2012, an outbreak of the KPC-2-producing K. pneumoniae was observed. The 48 isolates of K. pneumoniae are categorized into eight PFGE types (A1, A2, A3, A4, B, C, D and E). The predominant pathogens of the outbreak were strains with PFGE types A1, A2 and A3, which all belong to ST11. Furthermore, ST37, ST392 and ST395 KPC-2-producing K. pneumoniae isolates have also been sporadically identified. The blaKPC-2 -carrying plasmids vary in size from 30 to 220 kb. The genetic environments of the blaKPC-2 gene for most strains were consistent with the genetic structure of blaKPC-2 on the plasmid pKP048. In conclusion, the dissemination and outbreak of KPC-2-producing K. pneumoniae isolates in this study appeared to be clonal, and ST11 K. pneumoniae was the predominant clone attributed to the outbreak. This is the first study to report the emergence and spread of KPC-producing K. pneumoniae ST392 and ST395 worldwide. Our findings suggest that horizontal transfer of Tn3-based transposons might mediate the spread of blaKPC-2 gene between different K. pneumoniae clones in China.

  14. Marine biodiversity survey of St. Eustatius, 2015

    Hoeksema, B. W.


    The Statia Marine Biodiversity Expedition (2015) was organized by Naturalis Biodiversity Center in Leiden (the national museum of natural history of the Netherlands) and ANEMOON Foundation (a Dutch organisation of citizen scientists) in Bennebroek, The Netherlands. This field survey served as a baseline study to explore the marine biota of St. Eustatius, a small island on the boundary between the eastern Caribbean and the West Atlantic. Since 2010, St. Eustatius is part of the Caribbean Nethe...

  15. 31st Winter Workshop in Nuclear Dynamics


    The 31st edition of the Winter Workshop will be held January 25-31st, 2015 in the Keystone Resort, Colorado, USA. As with previous years, the workshop will bring together scientists from all fields of nuclear physics for engaging and friendly exchanges of ideas. Much emphasis will be on the recent LHC and RHIC heavy ion results, but advances in the ongoing and future programs at FAIR, FRIB, NICA and JLab will also be featured.

  16. St. Augustine in Twentieth-Century Music

    Petersen, Nils Holger


    A discussion - in a cultural historical perspective - of primarily two important twentieth-century musical works setting texts by St Augustine: Klaus Huber's Soliloquia Sancti Aurelii Augustini and Michael Tippett's The Vision of Saint Augustine.......A discussion - in a cultural historical perspective - of primarily two important twentieth-century musical works setting texts by St Augustine: Klaus Huber's Soliloquia Sancti Aurelii Augustini and Michael Tippett's The Vision of Saint Augustine....

  17. St Sava and the cloud-chasers

    Loma Aleksandar


    Full Text Available A gloss in the Nomocanon of St Sava condemns folk superstitions related to magically provoking hailstorms and eclipses. St Sava’s miracle with the king of Hungary as described in his Vitae seems to go back to the same complex of popular beliefs. Its acceptance by the hagiography was probably due to the influence of the figure of prince magician as common to the Serbian and the Russian oral epics.

  18. Fossil fuels in the 21st century.

    Lincoln, Stephen F


    An overview of the importance of fossil fuels in supplying the energy requirements of the 21st century, their future supply, and the impact of their use on global climate is presented. Current and potential alternative energy sources are considered. It is concluded that even with substantial increases in energy derived from other sources, fossil fuels will remain a major energy source for much of the 21st century and the sequestration of CO2 will be an increasingly important requirement.

  19. Coherent structures and transport in drift wave plasma turbulence

    Bang Korsholm, S.


    Fusion energy research aims at developing fusion power plants providing safe and clean energy with abundant fuels. Plasma turbulence induced transport of energy and particles is a performance limiting factor for fusion devices. Hence the understanding of plasma turbulence is important for optimization. The present work is a part of the puzzle to understand the basic physics of transport induced by drift wave turbulence in the edge region of a plasma. The basis for the study is the Hasegawa-Wakatani model. Simulation results for 3D periodic and nonperiodic geometries are presented. The Hasegawa-Wakatani model is further expanded to include ion temperature effects. Another expansion of the model is derived from the Braginskii electron temperature equation. The result is a self-consistent set of equations describing the dynamical evolution of the drift wave fluctuations of the electron density, electron temperature and the potential in the presence of density and temperature gradients. 3D simulation results of the models are presented. Finally, the construction and first results from the MAST fluctuation reflectometer is described. The results demonstrate how L- to H-mode transitions as well as edge-localized-modes can be detected by the relatively simple diagnostic system. The present Risoe report is a slightly updated version of my original PhD report which was submitted in April 2002 and defended in August 2002. (Author)

  20. Divertor plasma physics experiments on the DIII-D tokamak

    Mahdavi, M.A.; Allen, S.L.; Evans, T.E. [and others


    In this paper we present an overview of the results and conclusions of our most recent divertor physics and development work. Using an array of new divertor diagnostics we have measured the plasma parameters over the entire divertor volume and gained new insights into several divertor physics issues. We present direct experimental evidence for momentum loss along the field lines, large heat convection, and copious volume recombination during detachment. These observations are supported by improved UEDGE modeling incorporating impurity radiation. We have demonstrated divertor exhaust enrichment of neon and argon by action of a forced scrape off layer (SOL) flow and demonstrated divertor pumping as a substitute for conventional wall conditioning. We have observed a divertor radiation zone with a parallel extent that is an order of magnitude larger than that estimated from a 1-D conduction limited model of plasma at coronal equilibrium. Using density profile control by divertor pumping and pellet injection we have attained H-mode confinement at densities above the Greenwald limit. Erosion rates of several candidate ITER plasma facing materials are measured and compared with predictions of a numerical model.

  1. Effect of entropy on anomalous transport in ITG-modes of magneto-plasma

    Yaqub Khan, M.; Qaiser Manzoor, M.; Haq, A. ul; Iqbal, J.


    The ideal gas equation and S={{c}v}log ≤ft(P/ρ \\right) (where S is entropy, P is pressure and ρ is the mass density) define the interconnection of entropy with the temperature and density of plasma. Therefore, different phenomena relating to plasma and entropy need to be investigated. By employing the Braginskii transport equations for a nonuniform electron–ion magnetoplasma, two new parameters—the entropy distribution function and the entropy gradient drift—are defined, a new dispersion relation is obtained, and the dependence of anomalous transport on entropy is also proved. Some results, like monotonicity, the entropy principle and the second law of thermodynamics, are proved with a new definition of entropy. This work will open new horizons in fusion processes, not only by controlling entropy in tokamak plasmas—particularly in the pedestal regions of the H-mode and space plasmas—but also in engineering sciences.

  2. ITER-EDA physics design requirements and plasma performance assessments

    Uckan, N.A.; Galambos, J. [Oak Ridge National Lab., TN (United States); Wesley, J.; Boucher, D.; Perkins, F.; Post, D.; Putvinski, S. [ITER San Diego Joint Work Site, CA (United States)


    Physics design guidelines, plasma performance estimates, and sensitivity of performance to changes in physics assumptions are presented for the ITER-EDA Interim Design. The overall ITER device parameters have been derived from the performance goals using physics guidelines based on the physics R&D results. The ITER-EDA design has a single-null divertor configuration (divertor at the bottom) with a nominal plasma current of 21 MA, magnetic field of 5.68 T, major and minor radius of 8.14 m and 2.8 m, and a plasma elongation (at the 95% flux surface) of {approximately}1.6 that produces a nominal fusion power of {approximately}1.5 GW for an ignited burn pulse length of {ge}1000 s. The assessments have shown that ignition at 1.5 GW of fusion power can be sustained in ITER for 1000 s given present extrapolations of H-mode confinement ({tau}{sub E} = 0.85 {times} {tau}{sub ITER93H}), helium exhaust ({tau}*{sub He}/{tau}{sub E} = 10), representative plasma impurities (n{sub Be}/n{sub e} = 2%), and beta limit [{beta}{sub N} = {beta}(%)/(I/aB) {le} 2.5]. The provision of 100 MW of auxiliary power, necessary to access to H-mode during the approach to ignition, provides for the possibility of driven burn operations at Q = 15. This enables ITER to fulfill its mission of fusion power ({approximately} 1--1.5 GW) and fluence ({approximately}1 MWa/m{sup 2}) goals if confinement, impurity levels, or operational (density, beta) limits prove to be less favorable than present projections. The power threshold for H-L transition, confinement uncertainties, and operational limits (Greenwald density limit and beta limit) are potential performance limiting issues. Improvement of the helium exhaust ({tau}*{sub He}/{tau}{sub E} {le} 5) and potential operation in reverse-shear mode significantly improve ITER performance.

  3. On the E-H transition in inductively coupled radio frequency oxygen plasmas: I. Density and temperature of electrons, ground state and singlet metastable molecular oxygen

    Wegner, Th; Küllig, C.; Meichsner, J.


    In this series of two papers, the E-H transition in a planar inductively coupled radio frequency discharge (13.56 MHz) in pure oxygen is studied using comprehensive plasma diagnostic methods. The electron density serves as the main plasma parameter to distinguish between the operation modes. The (effective) electron temperature, which is calculated from the electron energy distribution function and the difference between the floating and plasma potential, halves during the E-H transition. Furthermore, the pressure dependency of the RF sheath extension in the E-mode implies a collisional RF sheath for the considered total gas pressures. The gas temperature increases with the electron density during the E-H transition and doubles in the H-mode compared to the E-mode, whereas the molecular ground state density halves at the given total gas pressure. Moreover, the singlet molecular metastable density reaches 2% in the E-mode and 4% in the H-mode of the molecular ground state density. These measured plasma parameters can be used as input parameters for global rate equation calculations to analyze several elementary processes. Here, the ionization rate for the molecular oxygen ions is exemplarily determined and reveals, together with the optical excitation rate patterns, a change in electronegativity during the mode transition.

  4. St. James marine terminal facility description


    The US Department of Energy (DOE) currently owns and operates a marine terminal on the west bank of the Mississippi River at St. James, Louisiana. The St. James facility was constructed by the Department to provide marine services associated with the fill and drawdown of the Strategic Petroleum Reserve (SPR) crude oil storage facilities located at Bayou Choctaw and Weeks Island, Louisiana. Although strategic to the mission of the SPR in the event of a national emergency, the St. James terminal is situated such that it has a high potential to also serve the commercial industry`s needs for crude oil terminalling and storage. The St. James terminal is located approximately 45 miles west of New Orleans and 30 miles southeast of Baton Rouge, and approximately 160 miles upstream from the mouth of the Mississippi River. Construction of the St. James terminal was initiated in 1978 and was completed in 1980. Since then, the terminal has received and transferred over 125 million barrels of crude oil to the SPR sites for storage. For crude oil distribution, the St. James terminal was connected to the neighboring LOCAP terminal by a 0.1 mile 36-inch pipeline in 1981 and to the Capline terminal by a 0.5 mile 30-inch pipeline in 1988. The terminal also has a 30-inch pipeline connection to the Koch oil terminal which was used for initial fill purposes; however, this pipeline has been disconnected and is currently inactive. A complete description of the St. James terminal facilities, operational capabilities, operational certifications, and future Government requirements are presented in Sections 2, 3, 4, and 5 respectively.

  5. Epidemiologic characteristics associated with ST23 clones compared to ST1 and ST47 clones of Legionnaires disease cases in France

    P. Cassier


    Full Text Available In France, approximately 1200 cases of Legionnaires disease (LD are reported annually, and isolates are available for approximately 20% of cases identified since 2000. All Legionella pneumophila serogroup 1 (sg1 isolates are characterized by sequence-based typing at the National Reference Centre. LD cases caused by L. pneumophila sg1 reported from 2008 through 2012 were considered for the study. Our study objective was to describe cases according to their sequence type (ST. We also constructed multivariable modified Poisson regression models to estimate the incidence rate ratio (IRR and to identify characteristics potentially associated with ST23 clones compared to ST1 and ST47 clones. We studied 1192 patients infected by ST1 (n = 109, ST23 (n = 236, ST47 (n = 123 or other STs (n = 724. The geographic distribution of the ST23 cases across the country was significantly different compared to other ST groups. This genotype was significantly associated with the absence of corticosteroid therapy compared to ST1 (IRR = 0.56; p 0.016. Concerning exposure, the ST23 genotype was significantly less associated with hospital-acquired infections compared to ST1 (IRR = 0.32; p 0.001, but it was more associated with infections acquired in hospitals and elderly settings compared with ST47. Finally, the ST23 genotype was less frequently associated with travel than other STs. Despite the large number of cases of ST23 infection, we did not identify any characteristics specific to this ST. However, we identified independent associations between ST1 and nosocomial transmission and steroid therapy. These findings should encourage further exploration, especially in terms of environmental diffusion, strain virulence and host factors.

  6. 78 FR 23489 - Safety Zone; V.I. Carnival Finale, St. Thomas Harbor; St. Thomas, U.S.V.I.


    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; V.I. Carnival Finale, St. Thomas Harbor; St. Thomas, U.S.V.I. AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a safety zone on the waters of St. Thomas Harbor in St. Thomas, U.S. Virgin Islands during the...

  7. The marine Algal Vegetation of St. Martin, St. Eustatius and Saba (Netherlands Antilles)

    Vroman, M.


    Along the coast of St. Martin, St. Eustatius and Saba the rocks above sea-level often show a number of differently coloured zones. This is clearly visible when the coast over a larger distance is formed by one type of rock, as for instance on Saba. In many places a light-coloured belt is seen above

  8. The marine Algal Vegetation of St. Martin, St. Eustatius and Saba (Netherlands Antilles)

    Vroman, M.


    Along the coast of St. Martin, St. Eustatius and Saba the rocks above sea-level often show a number of differently coloured zones. This is clearly visible when the coast over a larger distance is formed by one type of rock, as for instance on Saba. In many places a light-coloured belt is seen above

  9. St. Thomas and St. John, U.S. Virgin Islands Coastal Digital Elevation Model

    National Oceanic and Atmospheric Administration, Department of Commerce — The 1/3 arc-second St. Thomas and St. John, U.S. Virgin Islands Coastal Digital Elevation Model will be used to support NOAA's tsunami forecast system and for...

  10. The Role of the st313-td Gene in Virulence of Salmonella Typhimurium ST313

    Herrero-Fresno, Ana; Wallrodt, Inke; Leekitcharoenphon, Pimlapas


    Multidrug-resistant Salmonella enterica serovar Typhimurium ST313 has emerged in sub-Saharan Africa causing severe infections in humans. Therefore, it has been speculated that this specific sequence type, ST313, carries factors associated with increased pathogenicity. We assessed the role in viru...

  11. Stückelberg formulation of holography

    Dvali, Gia; Gomez, Cesar; Wintergerst, Nico


    We suggest that holography can be formulated in terms of the information capacity of the Stückelberg degrees of freedom that maintain gauge invariance of the theory in the presence of an information boundary. These Stückelbergs act as qubits that account for a certain fraction of quantum information. Their information capacity is measured by the ratio of the inverse Stückelberg energy gap to the size of the system. Systems with the smallest gap are maximally holographic. For massless gauge systems this information measure is universally equal to the inverse coupling evaluated at the systems' length scale. In this language it becomes very transparent why the Stückelberg information capacity of black holes saturates the Bekenstein bound and accounts for the entire information of the system. The physical reason is that the strength of quantum interaction is bounded from below by the gravitational coupling, which scales as area. Observing the striking similarity between the scalings of the energy gap of the boundary Stückelberg modes and the Bogoliubov modes of critical many-body systems, we establish a connection between holography and quantum criticality through the correspondence between these modes.

  12. Draft Genome Sequences of Staphylococcus aureus AMRF1 (ST22) and AMRF2 (ST672), Ocular Methicillin-Resistant Isolates

    Velusamy, Nithya


    Sequence type 22 (ST22) and ST672 are the two major emerging clones of community-acquired methicillin-resistant Staphylococcus aureus in India. ST672 strains were found to cause severe ocular infections. We report the draft genome sequences of two emerging strains of methicillin-resistant S. aureus, AMRF1 (ST22) and AMRF2 (ST672), isolated from patients with ocular infections.

  13. Plasma Free Metanephrines

    ... be limited. Home Visit Global Sites Search Help? Plasma Free Metanephrines Share this page: Was this page helpful? Also known as: Plasma Metanephrines Formal name: Fractionated Plasma Free Metanephrines (Metanephrine ...

  14. Improved plasma accelerator

    Cheng, D. Y.


    Converging, coaxial accelerator electrode configuration operates in vacuum as plasma gun. Plasma forms by periodic injections of high pressure gas that is ionized by electrical discharges. Deflagration mode of discharge provides acceleration, and converging contours of plasma gun provide focusing.

  15. Plasma physics and fusion plasma electrodynamics

    Bers, Abraham


    Plasma is a ubiquitous state of matter at high temperatures. The electrodynamics of plasmas encompasses a large number of applications, from understanding plasmas in space and the stars, to their use in processing semiconductors, and their role in controlled energy generation by nuclear fusion. This book covers collective and single particle dynamics of plasmas for fully ionized as well as partially ionized plasmas. Many aspects of plasma physics in current fusion energy generation research are addressed both in magnetic and inertial confinement plasmas. Linear and nonlinear dynamics in hydrodynamic and kinetic descriptions are offered, making both simple and complex aspects of the subject available in nearly every chapter. The approach of dividing the basic aspects of plasma physics as "linear, hydrodynamic descriptions" to be covered first because they are "easier", and postponing the "nonlinear and kinetic descriptions" for later because they are "difficult" is abandoned in this book. For teaching purpose...

  16. Analyse of Maintenance Cost in ST

    Jenssen, B W


    An analyse has been carried out in ST concerning the total costs for the division. Even though the target was the maintenance costs in ST, the global budget over has been analysed. This has been done since there is close relation between investments & consolidation and the required level for maintenance. The purpose of the analyse was to focus on maintenance cost in ST as a ratio of total maintenance costs over the replacement value of the equipment, and to make some comparisons with other industries and laboratories. Families of equipment have been defined and their corresponding ratios calculated. This first approach gives us some "quantitative" measurements. This analyse should be combined with performance indicators (more "qualitative" measurements) that are telling us how well we are performing. This will help us in defending our budget, make better priorities, and we will satisfy the requirements from our external auditors.

  17. Materials for the 21st century

    Segal, David


    The book is a general text that shows how materials can contribute to solving problems facing nations in the 21st century. It is illustrated with diverse applications and highlights the potential of existing materials for everyday life, healthcare and the economies of nations. There are 13 chapters and a glossary of 500 materials with their descriptions, historical development, their use or potential use and a range of references. Specific areas include synthetic polymers (e.g. nylon), natural polymers (e.g. proteins, cellulose) and the role of materials in the development of digital computers and in healthcare. Solid-state lighting, energy supplies in the 21st century, disruptive technologies and intellectual property, in particular patents, are discussed. The book concludes by asking how the 21st century will be characterised. Will it be the Silicon Age, Genomic Age or New Polymer Age, as examples?

  18. Detection of methicillin-resistant Staphylococcus pseudintermedius ST169 and novel ST354 SCCmec II-III isolates related to the worldwide ST71 clone.

    Ishihara, K; Koizumi, A; Saito, M; Muramatsu, Y; Tamura, Y


    The recent appearance of methicillin-resistant Staphylococcus pseudintermedius (MRSP) is a concern for both veterinary and human healthcare. MRSP clonal lineages with sequence type (ST) 71-spa t02-staphylococcal cassette chromosome mec (SCCmec) II-III and ST68-spa t06-SCCmec V have spread throughout Europe and North America, respectively. The current study compared the molecular characteristics of 43 MRSP isolates from dogs in Japan with those of MRSP from previous reports using multilocus sequence typing based on seven housekeeping genes, SCCmec typing, and detection of antimicrobial resistance genes. Three related clonal lineages, ST71, ST169, and the newly registered ST354, were observed in SCCmec II-III isolates from Japan, despite MRSP SCCmec II-III isolates being thought to belong to a single clonal lineage. The majority of SCCmec II-III isolates belonging to ST169 (9/11) and ST354 (3/3), but not ST71 (0/11), harboured tetM. Four STs were observed for the SCCmec V isolates; however, neither ST68 nor related STs were found in the Japanese MRSP isolates. In conclusion, MRSP SCCmec II-III isolates from Japan belonged to ST71 and related STs (ST169 and ST354). A variety of MRSP SCCmec V clones, including some novel clones, were identified.

  19. The 21st Century as Whose Century?

    David Scott


    Full Text Available Macro-analysis and East-West encounter are shown through consideration of objective yet subjective constructed concepts for the international system and international economy in the 21st century. Three paradigms are considered, namely the 21st century as the ‘Pacific Century’, as ‘China’s Century’ and as the ‘Asian Century’. Overlaps are shown between these three paradigms, as also developments in time, and gradually shift in geographical location. The ‘Pacific Century’, and its associated Rimspeak, was the paradigm emerging in the late 1970s, knitting together America’s West Coast and the Japanese economy. By the late 1980s this was already shifting to talk of the 21st century likely to be an ‘Asian Century’ model, mark-1, based on the Pacific Asia dynamism shown by the ‘Asian Tigers’ and Japan. However, the Asian financial crash of 1997-8, and the economic downturn in Japan, meant that such an ‘Asian Century’ seemed premature as the 21st century arrived. Instead, it was China’s economic growth that seemed most evident, and with it the concept of the 21st century as ‘China’s Century’. However, in turn that has already been modified during the first decade of the century by India’s arrival as a rapidly growing economy. Consequently the 21st century as ‘China’s Century’ and as ‘India’s Century’ has been combined into talk of an ‘Asian Century’, mark-2.

  20. Nursing theory: the 21st century.

    Randell, B P


    On September 21, 1990, at the University of California, Los Angeles, Neuropsychiatric Institute and Hospital, six nurse theorists participated in a panel discussion on theory development for the 21st century. The theorists included Dorothy Johnson, Betty Neuman, Dorothea E. Orem, Rosemarie Rizzo Parse, Martha E. Rogers and Callista Roy. The panel provided the participants the opportunity to speculate on the course for future development of nursing knowledge. Three questions were posed to the panel relating to the development of their models, the direction nursing theory will take in the 21st century, and current research emerging from the extant theories. The panel also addressed questions from the audience.

  1. Omsorg/støtte i ungdomsskolen

    Vasseng, Eli Dahl


    Denne studien handler om forholdet mellom lærer-elev og ser på hvordan ungdomsskoleelever beskriver omsorgsfulle/støttende lærere og den betydning det har for motivasjon i skolearbeid og læringsmiljø. Jeg har tatt utgangspunkt i ungdomsskoleelevenes forståelse av fenomenet omsorg/støtte og brukt en fenomenologisk tilnærming med intervju som metode. Seks elever fra ungdomstrinnet ble intervjuet og jeg har brukt en intervjuguide som er bygget på det teoretiske rammeverket i oppgaven. Hovedt...

  2. 51st North American Chemical Residue Workshop.

    Yang, Paul; Martos, Perry; Barrett, Brad


    Manuscripts collected in this 51st North American Chemical Residue Workshop (NACRW) Symposium issue of the Journal of Agricultural and Food Chemistry (JAFC) were originally presented at the 51st NACRW meeting. The 2014 NACRW JAFC symposium collects 14 publications representing the broad range of topics in chemical analyses presented at the 2014 meeting. These include the analysis of chemical residues and contaminants in food, environment, feed, botanical, and bee samples as well as the application of quality control/quality assurance protocols in routine and method development.

  3. Statistics in the 21st century

    Wells, Martin T; Wells, Martin T


    Exactly what is the state of the art in statistics as we move forward into the 21st century? What promises, what trends does its future hold? Through the reflections of 70 of the world's leading statistical methodologists, researchers, theorists, and practitioners, Statistics in the 21st Century answers those questions. Originally published in the Journal of the American Statistical Association, this collection of vignettes examines our statistical past, comments on our present, and speculates on our future. Although the coverage is broad and the topics diverse, it reveals the essential intell

  4. Operation and maintenance in ST-MA

    Nunes, R


    This paper will review the Operation & Maintenance (O&M) activities in the ST-MA group, giving an overview of the services provided by the Group as well as the contract activities. As an introduction, a conceptual framework for O&M is proposed in order to better situate the domains of Operation and Maintenance respectively. The ST-MA activities shall be looked at through the three main service axes and special emphasis will be given to the contractual implementation, supervision and follow-up methodology.

  5. Evolution of electron hole propating in inhomogeneous plasma

    Dokgo, K.; Woo, M.; Choi, C.; Min, K. W.; Hwang, J.


    The evolution of electron hole (EH) propagation in the presence of plasma density inhomogeneity is investigated by both particle-in-cell (PIC) simulation and theory. At the beginning of simulation, EH is generated by plasma blob injection. When EH passes inhomogeneous plasma region, the EH potential (1st order) increases monotonically in proportion to the background plasma density (0th order). With this 1st order growth, 2nd order back and forth oscillations of the potential are observed in faster time scale compared to EH propagation time scale. A bulk motion of trapped electrons due to density gradient produces these potential oscillations and the frequency of 2nd order oscillation is found to be comparable to the bouncing frequency of these trapped particles. Using the theoretical technique introduced by Schwarzmeier, we discovered a normal mode localized in the 1st order EH potential with frequency comparable to average bounce frequency of trapped particle. Such mode has an odd symmetry that is exactly consistent with simulation result. Furthermore, ions are pushed backward in coherence with 2nd order potential in simulation. These coherent ions form into a train of backward propagating ion acoustic solitary waves (IASWs) that evolve to ion hole in simulation. Finally, EH starts to dissipate by nonlinear Landau damping and converge to another stable EH as it reaches high-density, homogenous region.

  6. Understanding plasma facing surfaces in magnetic fusion devices

    Skinner, C. H.; Capece, A. M.; Koel, B. E.; Roszell, J. P.


    The plasma-material interface is recognized to be the most critical challenge in the realization of fusion energy. Liquid metals offer a self-healing, renewable interface that bypasses present issues with solid, neutron-damaged materials such as tungsten. Lithium in particular has dramatically improved plasma performance in many tokamaks through a reduction of hydrogen recycling. However the detailed chemical composition and properties of the top few nm that interact with the plasma are often obscure. Surface analysis has proven to be a key tool in semiconductor processing and a new laboratory has been established at PPPL to apply surface science techniques to plasma facing materials. We have shown that lithiated PFC surfaces in tokamaks will likely be oxidized during the intershot interval. Present work is focused on deuterium uptake of solid and liquid metals for plasma density control and sub-micron scale wetting of liquid metals on their substrates. The long-term goal is to provide a material database for designing liquid metal plasma facing components for tokamaks such as National Spherical Torus Experiment-Upgrade (NSTX-U) and Fusion Nuclear Science Facility-ST (FNSF-ST). Support was provided through DOE-PPPL Contract Number is DE-AC02-09CH11466.

  7. Fusion plasma physics

    Stacey, Weston M


    This revised and enlarged second edition of the popular textbook and reference contains comprehensive treatments of both the established foundations of magnetic fusion plasma physics and of the newly developing areas of active research. It concludes with a look ahead to fusion power reactors of the future. The well-established topics of fusion plasma physics -- basic plasma phenomena, Coulomb scattering, drifts of charged particles in magnetic and electric fields, plasma confinement by magnetic fields, kinetic and fluid collective plasma theories, plasma equilibria and flux surface geometry, plasma waves and instabilities, classical and neoclassical transport, plasma-materials interactions, radiation, etc. -- are fully developed from first principles through to the computational models employed in modern plasma physics. The new and emerging topics of fusion plasma physics research -- fluctuation-driven plasma transport and gyrokinetic/gyrofluid computational methodology, the physics of the divertor, neutral ...

  8. A path to stable low-torque plasma operation in ITER with test blanket modules

    Lanctot, M. J.; Snipes, J. A.; Reimerdes, H.; Paz-Soldan, C.; Logan, N.; Hanson, J. M.; Buttery, R. J.; deGrassie, J. S.; Garofalo, A. M.; Gray, T. K.; Grierson, B. A.; King, J. D.; Kramer, G. J.; La Haye, R. J.; Pace, D. C.; Park, J.-K.; Salmi, A.; Shiraki, D.; Strait, E. J.; Solomon, W. M.; Tala, T.; Van Zeeland, M. A.


    New experiments in the low-torque ITER Q  =  10 scenario on DIII-D demonstrate that n  =  1 magnetic fields from a single row of ex-vessel control coils enable operation at ITER performance metrics in the presence of applied non-axisymmetric magnetic fields from a test blanket module (TBM) mock-up coil. With n  =  1 compensation, operation below the ITER-equivalent injected torque is successful at three times the ITER equivalent toroidal magnetic field ripple for a pair of TBMs in one equatorial port, whereas the uncompensated TBM field leads to rotation collapse, loss of H-mode and plasma current disruption. In companion experiments at high plasma beta, where the n  =  1 plasma response is enhanced, uncorrected TBM fields degrade energy confinement and the plasma angular momentum while increasing fast ion losses; however, disruptions are not routinely encountered owing to increased levels of injected neutral beam torque. In this regime, n  =  1 field compensation leads to recovery of a dominant fraction of the TBM-induced plasma pressure and rotation degradation, and an 80% reduction in the heat load to the first wall. These results show that the n  =  1 plasma response plays a dominant role in determining plasma stability, and that n  =  1 field compensation alone not only recovers most of the impact on plasma performance of the TBM, but also protects the first wall from potentially damaging heat flux. Despite these benefits, plasma rotation braking from the TBM fields cannot be fully recovered using standard error field control. Given the uncertainty in extrapolation of these results to the ITER configuration, it is prudent to design the TBMs with as low a ferromagnetic mass as possible without jeopardizing the TBM mission.

  9. Core Fueling and Edge Particle Flux Analysis in Ohmically and Auxiliary Heated NSTX Plasmas

    V.A. Soukhanovskii; R. Maingi; R. Raman; H.W. Kugel; B.P. LeBlanc; L. Roquemore; C.H. Skinner; NSTX Research Team


    The Boundary Physics program of the National Spherical Torus Experiment (NSTX) is focusing on optimization of the edge power and particle flows in b * 25% L- and H-mode plasmas of t {approx} 0.8 s duration heated by up to 6 MW of high harmonic fast wave and up to 5 MW of neutral beam injection. Particle balance and core fueling efficiencies of low and high field side gas fueling of L-mode homic and NBI heated plasmas have been compared using an analytical zero dimensional particle balance model and measured ion and neutral fluxes. Gas fueling efficiencies are in the range of 0.05-0.20 and do not depend on discharge magnetic configuration, density or poloidal location of the injector. The particle balance modeling indicates that the addition of HFS fueling results in a reversal of the wall loading rate and higher wall inventories. Initial particle source estimates obtained from neutral pressure and spectroscopic measurements indicate that ion flux into the divertor greatly exceeds midplane ion flux from the main plasma, suggesting that the scrape-off cross-field transport plays a minor role in diverted plasmas. Present analysis provides the basis for detailed fluid modeling of core and edge particle flows and particle confinement properties of NSTX plasmas. This research was supported by the U.S. Department of Energy under contracts No. DE-AC02-76CH03073, DE-AC05-00OR22725, and W-7405-ENG-36.

  10. Equivalent circuit effects on mode transitions in H{sub 2} inductively coupled plasmas

    Xu, Hui-Jing; Zhao, Shu-Xia, E-mail:; Zhang, Yu-Ru; Gao, Fei; Li, Xue-Chun; Wang, You-Nian [Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)


    It is well known experimentally that the circuit matching network plays an important role in the mode transition behavior of inductively coupled plasmas. To date, however, there have been no reports of numerical models being used to study the role of the matching circuit in the transition process. In this paper, a new two-dimensional self-consistent fluid model that couples the components of an equivalent circuit module is developed to investigate the effects of the equivalent circuit on the mode transition characteristics of an inductively coupled, hydrogen plasma. The equivalent circuit consists of a current source, impedance matching network, reactor impedance, and plasma transferred impedance. The nonlinear coupling of the external circuit with the internal plasma is investigated by adjusting the matching capacitance at a fixed input current. The electron density and temperature as well as the electromagnetic fields all change suddenly, and the E to H mode transition occurs abruptly at a certain matching capacitance as the impedance matching of the external circuit is varied. We also analyze the fields and the plasma characteristics during the transition process, especially for the case of the capacitive E mode.

  11. The behavior of neutron emissions during ICRF minority heating of plasma at EAST

    Zhong, Guoqiang; Cao, Hongrui; Hu, Liqun; Zhou, Ruijie; Xiao, Min; Li, Kai; Pu, Neng; Huang, Juan; Liu, Guangzhu; Lin, Shiyao; Lyu, Bo; Liu, Haiqing; Zhang, Xinjun; EAST Team


    Ion cyclotron radio frequency (ICRF) wave heating is a primary method to heat ions in the Experimental Advanced Superconducting Tokamak (EAST). Through neutron diagnostics, effective ion heating was observed in hydrogenminority heating (MH) scenarios. At present, investigation of deuterium-deuterium (DD) fusion neutrons is mostly based on time-resolved flux monitor and spectrometer measurements. When the ICRF was applied, the neutron intensity became one order higher. The H/H  +  D ratio was in the range of 5-10%, corresponding to the hydrogen MH dominated scenario, and a strong high energy tail was not displayed on the neutron spectrum that was measured by a liquid scintillator. Moreover, ion temperature in the plasma center (T i) was inversely calculated by the use of neutron source strength (S n) and the plasma density based on classical fusion reaction equations. This result indicates that T i increases by approximately 30% in L-mode plasma, and by more than 50% in H-mode plasma during ICRF heating, which shows good agreement with x-ray crystal spectrometer (XCS) diagnostics. Finally, the DD neutron source strength scaling law, with regard to plasma current (I P) and ICRF coupling power (P RF) on the typical minority heating condition, was obtained by statistical analysis.

  12. Plasma Shape and Current Density Profile Control in Advanced Tokamak Operating Scenarios

    Shi, Wenyu

    -point position. Setting up a suitable toroidal current profile is related to both the stability and performance of the plasma. The requirements of ITER motivate the research on plasma current profile control. Currently, physics-based control-oriented modeling techniques of the current profile evolution can be separated into two major classes: data-driven and first-principles-driven. In this dissertation, a two-timescale linear dynamic data-driven model of the rotational transform profile and betaN is identified based on experimental data from the DIII-D tokamak. A mixed-sensitivity Hinfinity controller is developed and tested during DIII-D high-confinement (H-mode) experiments by using the heating and current drive (H&CD) systems to regulate the plasma rotational transform profile and betaN around particular target values close to the reference state used for system identification. The preliminary experimental results show good progress towards routine current profile control in DIII-D. As an alternative, a nonlinear dynamic first-principles-driven model is obtained by converting the physics-based model that describes the current profile evolution in H-mode DIII-D discharges into a form suitable for control design. The obtained control-oriented model is validated by comparing the model prediction to experimental data. An Hinfinity control design problem is formulated to synthesize a stabilizing feedback controller, with the goal of developing a closed-loop controller to drive the current profile in DIII-D to a desirable target evolution. Simulations show that the controller is capable of regulating the system around the target rotational transform profile in the presence of disturbances. When compared to a previously designed data-driven model-based controller, the proposed first-principles-driven model-based controller shows potential for improving the control performance.

  13. International movement of plasma and plasma contracting.

    Farrugia, A


    Plasma fractionation is a global business characterised by technological stability, increasing consolidation and a high level of regulatory oversight. All these factors affect the ease with which plasma derivatives can be accessed in the world market. As domestic regulatory measures in the first world blood economies become increasingly resonant to the precautionary approach, the availability of plasma as a raw material, as well as its cost, become an increasingly significant component in the cost of the final product. This decreases the amount of plasma which fractionators are able to allocate for export activities. Also, regulatory standards in the country of manufacture will reflect priorities in that country which may not be similar to those in export markets, but which will affect entry to those markets. While many countries possess a fractionation capacity, the limiting factor in supply worldwide is the amount of plasma available, and nationalistic drivers for each country to have its own plant are inimical to product safety and supply. Rather, the provision of sufficient supplies of domestic plasma should be the focus of resource allocation, with a choice of an appropriate contract fractionator. However, contract fractionation too may be affected by domestic considerations unrelated to the needs of the country of plasma origin. This chapter will review the global plasma market and the influences on plasma and plasma product movement across national borders. Problems in ensuring adequate safety and supply will be identified, and some tentative approaches to the amelioration of current barriers to the provision of plasma derivatives will be outlined.

  14. Multispecies density peaking in gyrokinetic turbulence simulations of low collisionality Alcator C-Mod plasmas

    Mikkelsen, D. R., E-mail:; Bitter, M.; Delgado-Aparicio, L.; Hill, K. W. [Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543 (United States); Greenwald, M.; Howard, N. T.; Hughes, J. W.; Rice, J. E. [MIT Plasma Science and Fusion Center, 175 Albany St., Cambridge, Massachusetts 02139 (United States); Reinke, M. L. [MIT Plasma Science and Fusion Center, 175 Albany St., Cambridge, Massachusetts 02139 (United States); York Plasma Institute, Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom); Podpaly, Y. [MIT Plasma Science and Fusion Center, 175 Albany St., Cambridge, Massachusetts 02139 (United States); AAAS S and T Fellow placed in the Directorate for Engineering, NSF, 4201 Wilson Blvd., Arlington, Virginia 22230 (United States); Ma, Y. [MIT Plasma Science and Fusion Center, 175 Albany St., Cambridge, Massachusetts 02139 (United States); ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St Paul Lez Durance Cedex (France); Candy, J.; Waltz, R. E. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)


    Peaked density profiles in low-collisionality AUG and JET H-mode plasmas are probably caused by a turbulently driven particle pinch, and Alcator C-Mod experiments confirmed that collisionality is a critical parameter. Density peaking in reactors could produce a number of important effects, some beneficial, such as enhanced fusion power and transport of fuel ions from the edge to the core, while others are undesirable, such as lower beta limits, reduced radiation from the plasma edge, and consequently higher divertor heat loads. Fundamental understanding of the pinch will enable planning to optimize these impacts. We show that density peaking is predicted by nonlinear gyrokinetic turbulence simulations based on measured profile data from low collisionality H-mode plasma in Alcator C-Mod. Multiple ion species are included to determine whether hydrogenic density peaking has an isotope dependence or is influenced by typical levels of low-Z impurities, and whether impurity density peaking depends on the species. We find that the deuterium density profile is slightly more peaked than that of hydrogen, and that experimentally relevant levels of boron have no appreciable effect on hydrogenic density peaking. The ratio of density at r/a = 0.44 to that at r/a = 0.74 is 1.2 for the majority D and minority H ions (and for electrons), and increases with impurity Z: 1.1 for helium, 1.15 for boron, 1.3 for neon, 1.4 for argon, and 1.5 for molybdenum. The ion temperature profile is varied to match better the predicted heat flux with the experimental transport analysis, but the resulting factor of two change in heat transport has only a weak effect on the predicted density peaking.

  15. Tungsten transport in the plasma edge at ASDEX upgrade

    Janzer, Michael Arthur


    The Plasma Facing Components (PFC) will play a crucial role in future deuterium-tritium magnetically confined fusion power plants, since they will be subject to high energy and particle loads, but at the same time have to ensure long lifetimes and a low tritium retention. These requirements will most probably necessitate the use of high-Z materials such as tungsten for the wall materials, since their erosion properties are very benign and, unlike carbon, capture only little tritium. The drawback with high-Z materials is, that they emit strong line radiation in the core plasma, which acts as a powerful energy loss mechanism. Thus, the concentration of these high-Z materials has to be controlled and kept at low levels in order to achieve a burning plasma. Understanding the transport processes in the plasma edge is essential for applying the proper impurity control mechanisms. This control can be exerted either by enhancing the outflux, e.g. by Edge Localized Modes (ELM), since they are known to expel impurities from the main plasma, or by reducing the influx, e.g. minimizing the tungsten erosion or increasing the shielding effect of the Scrape Off Layer (SOL). ASDEX Upgrade (AUG) has been successfully operating with a full tungsten wall for several years now and offers the possibility to investigate these edge transport processes for tungsten. This study focused on the disentanglement of the frequency of type-I ELMs and the main chamber gas injection rate, two parameters which are usually linked in H-mode discharges. Such a separation allowed for the first time the direct assessment of the impact of each parameter on the tungsten concentration. The control of the ELM frequency was performed by adjusting the shape of the plasma, i.e. the upper triangularity. The radial tungsten transport was investigated by implementing a modulated tungsten source. To create this modulated source, the linear dependence of the tungsten erosion rate at the Ion Cyclotron Resonance

  16. Reality Therapy for the 21st Century.

    Wubbolding, Robert E.

    This book serves as a comprehensive and practical guide to reality therapy, and extends its principles and practices beyond the initial descriptions. A central theme of this edition is that reality therapy is a method inherently designed for the exigencies of the 21st century. It contains 22 types of self-evaluations counselors can use to shorten…

  17. St\\"uckelberg Formulation of Holography

    Dvali, Gia; Wintergerst, Nico


    We suggest that holography can be formulated in terms of the information capacity of the St\\"uckelberg degrees of freedom that maintain gauge invariance of the theory in the presence of an information boundary. These St\\"uckelbergs act as qubits that account for a certain fraction of quantum information. Their information capacity is measured by the ratio of the inverse St\\"uckelberg energy gap to the size of the system. Systems with the smallest gap are maximally holographic. For massless gauge systems this information measure is universally equal to the inverse coupling evaluated at the systems' length scale. In this language it becomes very transparent why the St\\"uckelberg information capacity of black holes saturates the Bekenstein bound and accounts for the entire information of the system. The physical reason is that the strength of quantum interaction is bounded from below by the gravitational coupling, which scales as area. Observing the striking similarity between the scalings of the energy gap of t...

  18. Støtte til vedvarende energi?

    Olsen, Ole Jess; Skytte, Klaus; Grenaa Jensen, Stine

    er gået mere trægt. Hvad er forklaringen på de meget forskellige erfaringer? Kan succesen gentages for andre teknologier blot ved at kopiere støtte- og rammebetingelserne fra vindkraft? Disse spørgsmål søges besvaret i bogen. Erfaringskurver og relevant innovationsteori gennemgås, og der opstilles en...

  19. Creating 21st Century Learning Environments

    Li, Phan P.; Locke, John; Nair, Prakash; Bunting, Andrew


    What is involved in creating learning environments for the 21st century? How can school facilities serve as tools for teaching and meet the needs of students in the future? What components are required to design effective schools, and how does architecture relate to the purposes of schooling? These are some of the questions addressed at the…

  20. Soaring into the 21st Century.

    Burke, John


    Describes the implementation of ideas from the National Congress on Catholic Schools for the 21st Century at Saint Thomas Aquinas School in the South Bronx. Discusses Catholic identity, school spirit, social change, and school development with respect to the school's long-range planning for success in an economically depressed neighborhood. (MAB)

  1. St. Vincent Island : Then and Now

    US Fish and Wildlife Service, Department of the Interior — This report captures the memories and observations of Charles F. Marks, Jr. who lived on St. Vincent Island as a child. He recalls what it was like growing up on the...

  2. Toward the 21st Century for Women

    Osborn, Ruth H.


    The International Women's Year Conference decided that the key to the future for women throughout the world was continuing education enabling women to gain a sense of self realization, promote family life, increase options, and to contribute their talents to a better world in the 21st century. (Author/BP)

  3. St. Louis Educational Museum: A Centennial Commemoration

    Allen, James A.


    The St. Louis, Missouri Educational Museum has its roots in the 1904 Centennial Exposition, held at Forest Park on the edge of the city. The theme of the exposition was education and technology. Seventy thousand local school children visited the exposition, and at its conclusion an initiative was launched to purchase some of the exhibitions as…

  4. St Vincent Youth and Careers in Agriculture

    Webster, Nicole; Ganpat, Wayne


    Purpose: Given the ageing farming population in the Caribbean and the importance of agriculture to economy, there is cause for concern about the future of farming. This study seeks to explore the extent to which students pursuing agriculture in secondary schools in St Vincent and the Grenadines (SVG) were likely to engage in farming as well as…

  5. Possible Future SOFC - ST Based Power Plants

    Rokni, Masoud; Scappin, Fabio


    Hybrid systems consisting Solid Oxide Fuel Cell (SOFC) on the top of a Steam Turbine (ST) are investigated. The plants are fired by natural gas. A desulfurization reactor removes the sulfur content in the NG while a pre-reformer break down the heavier hydrocarbons. The pre-treated fuel enters...

  6. The 21st Century Information Environment.

    Badger, Rod

    This paper on the 21st century information environment begins with a section that discusses the impact of e-commerce over the next ten years. The second section addresses government focus areas, including ensuring a telecommunications infrastructure, developing the IT (information technology) industry, promoting innovation and entrepreneurship,…

  7. Action Research at St Mark's Academy 2013

    Elwick, Alex, Ed.; Riggall, Anna, Ed.


    St Mark's Church of England Academy is an 11-18 academy situated in Mitcham, South London. It offers a commitment to high achievement within a community of care, underpinned by the Christian values of hope, love and trust. The academy encourages the development of the moral and spiritual well-being of students, alongside their academic success.…

  8. Material Connections: Steuart Building, St. Albans School.

    Stephens, Suzanne


    The addition to the St. Albans campus in Washington, D.C., relates both to the style and the siting of the older "collegiate gothic" school nearby. The mixed-use building contains five classrooms, art and music spaces, and a student lounge. (Author/MLF)

  9. St Vincent Youth and Careers in Agriculture

    Webster, Nicole; Ganpat, Wayne


    Purpose: Given the ageing farming population in the Caribbean and the importance of agriculture to economy, there is cause for concern about the future of farming. This study seeks to explore the extent to which students pursuing agriculture in secondary schools in St Vincent and the Grenadines (SVG) were likely to engage in farming as well as…

  10. Bathymetry (2011) for Coral Bay, St. John

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a LiDAR (Light Detection & Ranging) 0.3x0.3 meter resolution depth surface for Coral Bay, St. John in the U.S. Virgin Islands (USVI). The...

  11. Learning Analytics for 21st Century Competencies

    Buckingham Shum, Simon; Crick, Ruth Deakin


    Many educational institutions are shifting their teaching and learning towards equipping students with knowledge, skills, and dispositions that prepare them for lifelong learning, in a complex and uncertain world. These have been termed "21st century competencies." Learning analytics (LA) approaches in general offer different kinds of…

  12. Highlights of 41st IATEFL Conference (Ⅱ)

    Rathi Manohar


    @@ For this year's 41 st International Annual IATEFL Conference in Aberdeen,IATEFL and the British Council worked together to enable teacher audiences worldwide to participate in this year's IATEFL Conference via the interact and get a taste of exactly what happens over four exciting days each year around Easter.

  13. Eesti goes St. Etienne / Anna Roomet

    Roomet, Anna


    Näitus Eesti Kunstiakadeemia tootedisaini osakonna magistrantide viimase kahe aasta projektide paremikust esindas Eestit disainibiennaalil St. Etiennis Prantsusmaal. Näituse panid üles Pent Talvet ja Pavel Sidorenko, näitusel osalejad: Anna-Maria Einla, Kätlin Kangur, Triin Kuusler, Andri Laidre, Veiko Liis, Liina-Kai Raivet, P. Sidorenko, P. Talvet, Ingela Viks, Triin Voss

  14. Ambulant ST-segmentmonitorering efter akut myokardieinfarkt

    Mickley, H; Junker, A; Friis, E V


    Over the last decade the concept of silent myocardial ischaemia has received considerable attention. Without doubt, the increased use of ambulatory ST-segment monitoring is the most important reason for the growing interest in this field. The prevalence of ambulatory ischaemia after myocardial in...

  15. Bathymetry (2011) for Fish Bay, St. John

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a LiDAR (Light Detection & Ranging) 0.3x0.3 meter resolution depth surface for Fish Bay, St. John in the U.S. Virgin Islands (USVI). The...

  16. Digital Humanities in the 21st Century

    Brügger, Niels


    In this article it is argued that one of the major transformative factors of the humanities at the beginning of the 21st century is the shift from analogue to digital source material, and that this shift will affect the humanities in a variety of ways. But various kinds of digital material...

  17. Theory of self-sustained turbulence in confined plasmas

    Itoh, Kimitaka; Itoh, Sanae; Fukuyama, Atsushi; Yagi, Masatoshi


    This article overviews some aspect of the recent theoretical activities in Japan on the problem of turbulent transport in confined plasmas. The method of self-sustained turbulence is discussed. The process of the renormalization is shown and the turbulent Prandtl number is introduced. Nonlinear destabilization by the electron momentum diffusion is explained. The nonlinear eigenmode equation is derived for the dressed-test-mode for the inhomogeneous plasma in the shear magnetic field. The eigenvalue equation is solved, and the least stable mode determines the anomalous transport coefficient. Formula of thermal conductivity is presented for the system of bad average magnetic curvature (current diffusive interchange mode (CDIM) turbulence) and that for the average good magnetic curvature (current diffusive ballooning mode (CDBM) turbulence). The transport coefficient, scale length of fluctuations and fluctuation level are shown to be the increasing function of the pressure gradient. Verification by use of the nonlinear simulation is shown. The bifurcation of the electric field and improved confinement is addressed, in order to explain the H-mode physics. Improved confinement and the dynamics such as ELMs are explained. Application to the transport analysis of tokamaks is also presented, including the explanations of the L-mode confinement, internal transport barrier as well as the role of current profile control. (author). 102 refs.

  18. Atmospheric pressure plasma polymers for tuned QCM detection of protein adhesion.

    Rusu, G B; Asandulesa, M; Topala, I; Pohoata, V; Dumitrascu, N; Barboiu, M


    Our efforts have been concentrated in preparing plasma polymeric thin layers at atmospheric pressure grown on Quartz Crystal Microbalance-QCM electrodes for which the non-specific absorption of proteins can be efficiently modulated, tuned and used for QCM biosensing and quantification. Plasma polymerization reaction at atmospheric pressure has been used as a simple and viable method for the preparation of QCM bioactive surfaces, featuring variable protein binding properties. Polyethyleneglycol (ppEG), polystyrene (ppST) and poly(ethyleneglycol-styrene) (ppST-EG) thin-layers have been grown on QCM electrodes. These layers were characterized by Atomic Force Microscopy (AFM), Contact angle measurements, Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS). The plasma ppST QCM electrodes present a higher adsorption of Concanavalin A (ConA) and Bovine Serum Albumin (BSA) proteins when compared with the commercial coated polystyrene (ppST) ones. The minimum adsorption was found for ppEG, surface, known by their protein anti-fouling properties. The amount of adsorbed proteins can be tuned by the introduction of PEG precursors in the plasma discharge during the preparation of ppST polymers. © 2013 Elsevier B.V. All rights reserved.

  19. Henkilöstötilinpäätös ja henkilöstöstrategian pohja kohdeyritykselle

    Jäntti, Hanna


    Tämän toiminnallisen opinnäytetyön kautta tuotettiin kohdeyritykselle henkilöstötilinpäätös sekä pohja henkilöstöstrategialle. Työn toimeksiantaja oli Pohjois-Suomen alueella toimiva kehitysvammaisten palvelukoti, joka myy kehitysvammaispalveluilta kunnille sekä yksityisille yrityksille ja henkilöille. Henkilöstötilinpäätöstä tai henkilöstöstrategiaa ei ollut organisaatiossa aiemmin tehty. Opinnäytetyö jakaantui varsinaiseen opinnäytetyöraporttiin ja sen liitteinä oleviin henkilöstötilinp...

  20. Communication through Plasma Sheaths

    Korotkevich, A O; Zakharov, V E


    We wish to transmit messages to and from a hypersonic vehicle around which a plasma sheath has formed. For long distance transmission, the signal carrying these messages must be necessarily low frequency, typically 2 GHz, to which the plasma sheath is opaque. The idea is to use the plasma properties to make the plasma sheath appear transparent.

  1. LiDAR Relative Reflectivity Surface (2011) for the St. Thomas East End Reserve, St. Thomas

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a LiDAR (Light Detection & Ranging) 0.3x0.3 meter resolution relative seafloor reflectivity surface for the St. Thomas East End Reserve...

  2. Introduction to plasma dynamics

    Morozov, A I


    As the twenty-first century progresses, plasma technology will play an increasing role in our lives, providing new sources of energy, ion-plasma processing of materials, wave electromagnetic radiation sources, space plasma thrusters, and more. Studies of the plasma state of matter not only accelerate technological developments but also improve the understanding of natural phenomena. Beginning with an introduction to the characteristics and types of plasmas, Introduction to Plasma Dynamics covers the basic models of classical diffuse plasmas used to describe such phenomena as linear and shock w

  3. Neutron emission in neutral beam heated KSTAR plasmas and its application to neutron radiography

    Kwak, Jong-Gu, E-mail:; Kim, H.S.; Cheon, M.S.; Oh, S.T.; Lee, Y.S.; Terzolo, L.


    Highlights: • We measured the neutron emission from KSTAR plasmas quantitatively. • We confirmed that neutron emission is coming from neutral beam-plasma interactions. • The feasibility study shows that the fast neutron from KSTAR could be used for fast neutron radiography. - Abstract: The main mission of Korea Superconducting Tokamak Advanced Research (KSTAR) program is exploring the physics and technologies of high performance steady state Tokamak operation that are essential for ITER and fusion reactor. Since the successful first operation in 2008, the plasma performance is enhanced and duration of H-mode is extended to around 50 s which corresponds to a few times of current diffusion time and surpassing the current conventional Tokamak operation. In addition to long-pulse operation, the operational boundary of the H-mode discharge is further extended over MHD no-wall limit(β{sub N} ∼ 4) transiently and higher stored energy region is obtained by increased total heating power (∼6 MW) and plasma current (I{sub p} up to 1 MA for ∼10 s). Heating system consists of various mixtures (NB, ECH, LHCD, ICRF) but the major horse heating resource is the neutral beam(NB) of 100 keV with 4.5 MW and most of experiments are conducted with NB. So there is a lot of production of fast neutrons coming from via D(d,n){sup 3}He reaction and it is found that most of neutrons are coming from deuterium beam plasma interaction. Nominal neutron yield and the area of beam port is about 10{sup 13}–10{sup 14}/s and 1 m{sup 2} at the closest access position of the sample respectively and neutron emission could be modulated for application to the neutron radiography by varying NB power. This work reports on the results of quantitative analysis of neutron emission measurements and results are discussed in terms of beam-plasma interaction and plasma confinement. It also includes the feasibility study of neutron radiography using KSTAR.

  4. Habitat Management Plan for St. Marks National Wildlife Refuge

    US Fish and Wildlife Service, Department of the Interior — The St. Marks NWR Habitat Management Plan provides a long-term vision and specific guidance on managing habitats for the resources of concern at St. Marks NWR, to...

  5. Danish Stød: Laryngealization or Tone

    Grønnum, Nina; Vazquez-Larruacaín, Miguel; Basbøll, Hans


    In the light of previous acoustic analyses of Danish stød and Danish intonation, we discuss two different phonological theories. In one, stød is an autonomous laryngeal syllable prosody. In the other, stød is the phonetic manifestation of a HL tonal pattern compressed within one syllable. The tonal...... representation is found to be contradicted by the phonetic reality, and it cannot account for the structurally determined alternation between non-stød and stød in inflection and derivation, nor for latent stød or stød in compounds. Furthermore, stød patterns are largely constant across regional varieties...

  6. CDC WONDER: Population - Bridged-Race July 1st Estimates

    U.S. Department of Health & Human Services — The Population - Bridged-Race July 1st Estimates online databases report bridged-race population estimates of the July 1st resident population of the United States,...

  7. Collisionless plasmas in astrophysics

    Belmont, Gerard; Mottez, Fabrice; Pantellini, Filippo; Pelletier, Guy


    Collisionless Plasmas in Astrophysics examines the unique properties of media without collisions in plasma physics. Experts in this field, the authors present the first book to concentrate on collisionless conditions in plasmas, whether close or not to thermal equilibrium. Filling a void in scientific literature, Collisionless Plasmas in Astrophysics explains the possibilities of modeling such plasmas, using a fluid or a kinetic framework. It also addresses common misconceptions that even professionals may possess, on phenomena such as "collisionless (Landau) damping". Abundant illustrations

  8. A prospect at 11th international Toki conference. Plasma physics, quo vadis?

    Itoh, Kimitaka


    A prospect of plasma physics at the turn of next century is discussed. The theme of this conference identifies the future direction of the research related with plasmas. Main issue is the potential and structure formation in plasmas; More specifically, structures which are realized through the interaction of electromagnetic fields, in particular that with electric fields, in non-equilibrium state. An emphasis is made to clarify the fundamental physics aspects of the plasma physics in fusion research as well as that in the basic research of plasmas. The plasma physics will give an important contribution to the solution of the historical enigma, i.e., all things flow. Having an impact on human recognition of nature and showing a beauty in a law, the plasma physics/science will demonstrate to be a leading science in the 21st century. (author)

  9. Colloidal Plasmas : Basic physics of colloidal plasmas

    C B Dwivedi


    Colloidal plasma is a distinct class of the impure plasmas with multispecies ionic composition. The distinction lies in the phase distribution of the impurity-ion species. The ability to tailor the electrostatic interactions between these colloidal particles provides a fertile ground for scientists to investigate the fundamental aspects of the Coulomb phase transition behavior. The present contribution will review the basic physics of the charging mechanism of the colloidal particles as well as the physics of the collective normal mode behavior of the general multi-ion species plasmas. Emphasis will be laid on the clarification of the prevailing confusing ideas about distinct qualities of the various acoustic modes, which are likely to exist in colloidal plasmas as well as in normal multi-ion species plasmas. Introductory ideas about the proposed physical models for the Coulomb phase transition in colloidal plasma will also be discussed.

  10. 75 FR 8390 - St. Croix River Aids to Navigation


    ... SECURITY Coast Guard St. Croix River Aids to Navigation AGENCY: Coast Guard, DHS. ACTION: Notice of public... the aids to navigation in the St. Croix River. DATES: A public meeting will be held on Tuesday, March... review the current Aids to Navigation system on the St. Croix River and discuss concerns and...

  11. GeoTIFF of 3x3 m Bathymetry for St. Thomas & St. John, 2011, UTM 20N NAD83

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a LiDAR (Light Detection & Ranging) 3x3 meter resolution bathymetric surface for an area of shallow seabed surrounding St. Thomas and St....

  12. StCDPK5 confers resistance to late blight pathogen but increases susceptibility to early blight pathogen in potato via reactive oxygen species burst.

    Kobayashi, Michie; Yoshioka, Miki; Asai, Shuta; Nomura, Hironari; Kuchimura, Kazuo; Mori, Hitoshi; Doke, Noriyuki; Yoshioka, Hirofumi


    • Potato (Solanum tuberosum) calcium-dependent protein kinase (StCDPK5) has been shown to phosphorylate the N-terminal region of plasma membrane RBOH (respiratory burst oxidase homolog) proteins, and participate in StRBOHB-mediated reactive oxygen species (ROS) burst. The constitutively active form, StCDPK5VK, provides a useful tool for gain-of-function analysis of RBOH in defense responses. • StCDPK5- and StCDPK5VK-green fluorescent protein fusion proteins were predominantly targeted to the plasma membrane, and conditional expression of StCDPK5VK activated StRBOHA-D. The interaction was confirmed by bimolecular fluorescence complementation assay. We generated transgenic potato plants containing StCDPK5VK under the control of a pathogen-inducible promoter to investigate the role of ROS burst on defense responses to blight pathogens. • Virulent isolates of the late blight pathogen Phytophthora infestans and the early blight pathogen Alternaria solani induced hypersensitive response-like cell death accompanied by ROS production at the infection sites of transgenic plants. Transgenic plants showed resistance to the near-obligate hemibiotrophic pathogen P. infestans and, by contrast, increased susceptibility to the necrotrophic pathogen A. solani. • These results indicate that RBOH-dependent ROS contribute to basal defense against near-obligate pathogens, but have a negative role in resistance or have a positive role in expansion of disease lesions caused by necrotrophic pathogens. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  13. Nonlinear plasma wave in magnetized plasmas

    Bulanov, Sergei V. [Kansai Photon Science Institute, JAEA, Kizugawa, Kyoto 619-0215 (Japan); Prokhorov Institute of General Physics, Russian Academy of Sciences, Moscow 119991 (Russian Federation); Moscow Institute of Physics and Technology, Dolgoprudny, Moscow region 141700 (Russian Federation); Esirkepov, Timur Zh.; Kando, Masaki; Koga, James K. [Kansai Photon Science Institute, JAEA, Kizugawa, Kyoto 619-0215 (Japan); Hosokai, Tomonao; Zhidkov, Alexei G. [Photon Pioneers Center, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871 (Japan); Japan Science and Technology Agency, CREST, 2-1, Yamadaoka, Suita, Osaka 565-0871 (Japan); Kodama, Ryosuke [Photon Pioneers Center, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871 (Japan); Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)


    Nonlinear axisymmetric cylindrical plasma oscillations in magnetized collisionless plasmas are a model for the electron fluid collapse on the axis behind an ultrashort relativisically intense laser pulse exciting a plasma wake wave. We present an analytical description of the strongly nonlinear oscillations showing that the magnetic field prevents closing of the cavity formed behind the laser pulse. This effect is demonstrated with 3D PIC simulations of the laser-plasma interaction. An analysis of the betatron oscillations of fast electrons in the presence of the magnetic field reveals a characteristic “Four-Ray Star” pattern.

  14. Shape reconstruction of merging spherical tokamak plasma in UTST device

    Ushiki, Tomohiko; Itagaki, Masafumi; Inomoto, Michiaki


    Spherical tokamak (ST) merging method is one of the ST start-up methods which heats the plasma through magnetic reconnection. In the present study reconstruction of eddy current profile and plasma shape was performed during spherical tokamak merging only using external sensor signals by the Cauchy condition surface (CCS) method. CCS method have been implemented for JT-60 (QST), QUEST (Kyushu University), KSTAR (NFRI), RELAX (KIT), and LHD (Nifs). In this method, CCS was assumed inside each plasmas, where both flux function and its normal derivative are unknown. Effect of plasma current was replaced by the boundary condition of CCS, assuming vacuum field everywhere. Also, the nodal points for the boundary integrals of eddy current density were set using quadratic elements in order to express the complicated vacuum vessel shape. Reconstructed profiles of the eddy current and the magnetic flux were well coincided with the reference in each phase of merging process. Magnetic sensor installation plan for UTST was determined from these calculation results. This work was supported by the JSPS A3 Foresight Program ``Innovative Tokamak Plasma Startup and Current Drive in Spherical Torus''.

  15. Elements of plasma technology

    Wong, Chiow San


    This book presents some fundamental aspects of plasma technology that are important for beginners interested to start research in the area of plasma technology . These include the properties of plasma, methods of plasma generation and basic plasma diagnostic techniques. It also discusses several low cost plasma devices, including pulsed plasma sources such as plasma focus, pulsed capillary discharge, vacuum spark and exploding wire; as well as low temperature plasmas such as glow discharge and dielectric barrier discharge which the authors believe may have potential applications in industry. The treatments are experimental rather than theoretical, although some theoretical background is provided where appropriate. The principles of operation of these devices are also reviewed and discussed.

  16. Life Sciences in the 21 st Century

    Zou Chenglu (C. L. Tsou)


    This article presents a retrospective of the achievements of life sciences in the 20th century and a prospective in the 21 st century.primarily,because of the emergence of molecular biology in the 20th cetury,life sciences have grown up from a descriptive discipline to an exact science.Biology in the 21st century features a unification between analysis and integration,i.e.the unification of analysis and func-tional research.More and more interdisciplinary integration will be based on works of penetrating analyses.Secondly.the deeper understanding of all living phenomena will lead to a unified connition of the essence of life so that general biology in the genuine sese of the term will come into being.finally,basic research on the life sciences will produce an unprecedented influence on all aspects of human life.

  17. Danmarks Største Fossiler

    Lindow, Bent Erik Kramer; Cuny, Gilles Guy Roger


    For 8 millioner år siden myldrede Nordsøen af en mangfoldighed af hajer, hvaler, havskildpadder og sæler, mange flere end i dag. Blandt dem finder man Danmarks største fossiler som er udstillet på Museum Sønderjylland - Naturhistorie og Palæontologi i Gram.......For 8 millioner år siden myldrede Nordsøen af en mangfoldighed af hajer, hvaler, havskildpadder og sæler, mange flere end i dag. Blandt dem finder man Danmarks største fossiler som er udstillet på Museum Sønderjylland - Naturhistorie og Palæontologi i Gram....

  18. Building a St\\"uckelberg Portal

    Feng, Wan-Zhe; Soler, Pablo; Ye, Fang


    We construct explicit string theory models realizing the recently proposed "St\\"uckelberg Portal" scenario, a framework for building Z' mediation models without the need to introduce unwanted exotic matter charged under the Standard Model. This scenario can be viewed purely field-theoretically, although it is particularly well motivated from string theory. By analyzing carefully the St\\"uckelberg couplings between the Abelian gauge bosons and the RR axions, we construct the first global intersecting brane models which extend the Standard Model with a genuine hidden sector, to which it is nonetheless connected via U(1) mass mixings. Utilizing the explicit models we construct, we discuss some broad phenomenological properties and experimental implications of this scenario such as Z-Z' mixings, dark matter stability and relic density, and supersymmetry mediation. With an appropriate confining hidden sector, our setup also provides a minimal realization of the hidden valley scenario. We further explore the possib...

  19. Selective Reproduction in the 21st Century

    In the 21st century, human reproduction increasingly involves decisions about which gametes to fertilize, which embryos to implant, or which fetuses to abort. The term ‘selective reproduction’ refers to these increasingly widespread efforts to bring specific kinds of children into being....... To this end, selective reproductive technologies (SRTs) have been developed and routinized over the last few decades. In today’s world, selective reproduction is taking place on a historically unprecedented scale; through sex-selective abortions following ultrasound scans, termination of pregnancies following...... detection of fetal anomalies during prenatal screening and testing programs, the development of preimplantation genetic diagnosis techniques as well as the screening of potential gamete donors by egg agencies and sperm banks. Selective Reproduction in the 21st Century provides unique ethnographic insights...

  20. Støtte til vedvarende energi?

    Skytte, K.; Jensen, Stine Grenaa; Morthorst, Poul Erik

    Udvikling af teknologier til fremstilling af elektricitet ved brug af vedvarende energiteknologier har i mange år haft høj prioritet i Danmark og modtaget betydelig støtte. Resultaterne har været meget blandede. For nogle teknologier som vindkraft har udviklingen været en succes, mens den for andre...... er gået mere trægt. Hvad er forklaringen på de meget forskellige erfaringer? Kan succesen gentages for andre teknologier blot ved at kopiere støtte- og rammebetingelserne fra vindkraft? Disse spørgsmål søges besvaret i bogen. Erfaringskurver og relevant innovationsteori gennemgås, og der opstilles en...

  1. Detergents of the 21st century

    Ho Tan Tai Louis


    Full Text Available Detergents of the 21st century will depend on evolutions in household appliances, in substrates and in consumer needs. In addition, the environmental constraints, which become more and more stringent, will also play an important role, particularly in the formulations. Surfactants, which constitute one of the main raw materials in detergents, will have to be more environmentally friendly with increasing criteria of biodegradability and renewable materials. Builders (phosphates or zeolithes, heavy metal complexants (EDTA and bleaching agents (combination perborate/TAED are also expected to be replaced by biodegradable compounds, with better performances and lower costs. The real raw materials of the detergents of the 21st century will probably be enzymes (oxidase, hydrolase, peroxidase which present several advantages. At the same time, efforts will be made on biodegradable packaging through the use of micro-organisms able to degrade polymers. Finally, in terms of product forms, the concept of concentration might come back through the use of tablets.

  2. 78 FR 16211 - Safety Zone, Corp. Event Finale UHC, St. Thomas Harbor; St. Thomas, U.S. Virgin Islands


    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone, Corp. Event Finale UHC, St. Thomas Harbor... Harbor in St. Thomas, U.S. Virgin Islands during the Corp. Event Finale UHC firework display. The safety.... Event Finale UHC, ] a firework display. The event will be held on the waters of St. Thomas Harbor,...

  3. Baseline risk assessment for exposure to contaminants at the St. Louis Site, St. Louis, Missouri


    The St. Louis Site comprises three noncontiguous areas in and near St. Louis, Missouri: the St. Louis Downtown Site (SLDS), the St. Louis Airport Storage Site (SLAPS), and the Latty Avenue Properties. The main site of the Latty Avenue Properties includes the Hazelwood Interim Storage Site (HISS) and the Futura Coatings property, which are located at 9200 Latty Avenue. Contamination at the St. Louis Site is the result of uranium processing and disposal activities that took place from the 1940s through the 1970s. Uranium processing took place at the SLDS from 1942 through 1957. From the 1940s through the 1960s, SLAPS was used as a storage area for residues from the manufacturing operations at SLDS. The materials stored at SLAPS were bought by Continental Mining and Milling Company of Chicago, Illinois, in 1966, and moved to the HISS/Futura Coatings property at 9200 Latty Avenue. Vicinity properties became contaminated as a result of transport and movement of the contaminated material among SLDS, SLAPS, and the 9200 Latty Avenue property. This contamination led to the SLAPS, HISS, and Futura Coatings properties being placed on the National Priorities List (NPL) of the US Environmental Protection Agency (EPA). The US Department of Energy (DOE) is responsible for cleanup activities at the St. Louis Site under its Formerly Utilized Sites Remedial Action Program (FUSRAP). The primary goal of FUSRAP is the elimination of potential hazards to human health and the environment at former Manhattan Engineer District/Atomic Energy Commission (MED/AEC) sites so that, to the extent possible, these properties can be released for use without restrictions. To determine and establish cleanup goals for the St. Louis Site, DOE is currently preparing a remedial investigation/feasibility study-environmental impact statement (RI/FS-EIS). This baseline risk assessment (BRA) is a component of the process; it addresses potential risk to human health and the environment associated wi

  4. Pooling strategies for St Petersburg gamblers

    Csörgö, Sandor; Simons, Gordon


    Peter offers to play exactly one St Petersburg game with each of [math] players, Paul [math] , [math] , Paul [math] , whose conceivable pooling strategies are described by all possible probability distributions [math] . Comparing infinite expectations, we characterize among all [math] those admissible strategies for which the pooled winnings, each distributed as [math] , yield a finite added value for each and every one of Paul [math] , [math] , Paul [math] in comparison with their individual...

  5. 2011 EFFoST Annual Meeting, Berlin


    The 2011 European Federation of Food Science and Technology (EFFoST) conference took place in Berlin, Germany on 9-11 November. The conference programme centred on food process-structure-function relationships and the content was closely allied to the research agenda of the European Technology Platform: Food for Life. There were 16 keynote/review lectures, 38 other oral presentations, 260 posters, and close to 300 attendees. The oral sessions corresponded to the process-structure-function the...

  6. Pooling strategies for St Petersburg gamblers

    Csörgö, Sandor; Simons, Gordon


    Peter offers to play exactly one St Petersburg game with each of [math] players, Paul [math] , [math] , Paul [math] , whose conceivable pooling strategies are described by all possible probability distributions [math] . Comparing infinite expectations, we characterize among all [math] those admissible strategies for which the pooled winnings, each distributed as [math] , yield a finite added value for each and every one of Paul [math] , [math] , Paul [math] in comparison with their individual...

  7. The Geological Environment West of St. Croix


    determined to be late Cretaceous and younger. Fink, L.K., Jr. (1972). Bathymetric and Geologic Studies of the Guadeloupe Region, Lesser Antilles...Dominica through studies of the geology of the islands, particularly that of Guadeloupe and nearby submarine physiographic regions. The finding of Late...Living Birds of Puerto Rico. Jour, of Agriculture of the Union of Puerto Rico, v. 21, no. 1, p. 5-16. Whetten, J.R. (1961). Geology of St. Croix, U.S

  8. Reviews of plasma physics


    "Reviews of Plasma Physics Volume 24," edited by V.D. Shafranov, presents two reviews from the cutting-edge of Russian plasma physics research. The first review by V.A. Rozhansky devoted to the mechanisms of transverse conductivity and generation of self-consistent electric fields in strongly ionized magnetized plasma. The second review by O.G. Bakunin considers numerous aspects of turbulent transport in plasma and fluids. This review is focused on scaling arguments for describing anomalous diffusion in the presence of complex structures. These topics are especially important for fusion plasma research, plasma astrophysics, discharge physics, and turbulence

  9. Reviews of plasma physics

    Shafranov, Vitalii Dmitrievich (ed.); Bakunin, Oleg G. (comps.) [Rossijskij Nauchnyj Tsentr ' ' Kurchatovskij Inst.' ' , Moscow (Russian Federation). Nuclear Fusion Inst.; Rozhansky, V. [St. Petersburg State Polytechnical Univ. (Russian Federation)


    Reviews of Plasma Physics Volume 24, edited by V.D. Shafranov, presents two reviews from the cutting-edge of Russian plasma physics research. The first review by V.A. Rozhansky devoted to the mechanisms of transverse conductivity and generation of self-consistent electric fields in strongly ionized magnetized plasma. The second review by O.G. Bakunin considers numerous aspects of turbulent transport in plasma and fluids. This review is focused on scaling arguments for describing anomalous diffusion in the presence of complex structures. These topics are especially important for fusion plasma research, plasma astrophysics, discharge physics, and turbulence (orig.)

  10. Zdravotní středisko

    Fukanová, Lenka


    Projekt mé diplomové práce je novostavba zdravotního střediska. Jedná se o samostatně stojící budovu, která je situovaná na mírně svažitém terénu, který bude vyrovnán. Objekt je částečně podsklepený a má dvě nadzemní podlaží. V podzemním podlaží se nachází technické zázemí střediska. V prvním nadzemním podlaží je umístěna recepce, čekárna, sesterny, ordinace a lékárna. V druhém nadzemním podlaží jsou opět čekárny, sesterny, ordinace a cvičební sál. K objektu přiléhá parkoviště. Budova je zděn...

  11. Carl Størmer Auroral Pioneer

    Egeland, Alv


    This biography summarizes the seminal contributions to auroral and space science of Carl Størmer (1874 - 1957). He was the first to develop precise photographic methods to calculate heights and morphologies of diverse auroral forms during four solar cycles. Størmer independently devised numerical techniques to determine the trajectories of high-energy charged particles allowed and forbidden in the Earth’s magnetic field. His theoretical analyses explained cosmic ray access to the upper atmosphere, 20 years before they were identified by other scientists. Størmer’s crowning achievement, “The Polar Aurora,” published when he was 81 years old, stands to this day as a regularly cited guide in graduate-level courses on space physics.   The authors present the life of this prodigious scientist in relation to the cultural life of early 20th century in Norway and to the development of the space sciences in the post-Sputnik era.

  12. Solenoid-free plasma start-up in spherical tokamaks

    Raman, R.; Shevchenko, V. F.


    The central solenoid is an intrinsic part of all present-day tokamaks and most spherical tokamaks. The spherical torus (ST) confinement concept is projected to operate at high toroidal beta and at a high fraction of the non-inductive bootstrap current as required for an efficient reactor system. The use of a conventional solenoid in a ST-based fusion nuclear facility is generally believed to not be a possibility. Solenoid-free plasma start-up is therefore an area of extensive worldwide research activity. Solenoid-free plasma start-up is also relevant to steady-state tokamak operation, as the central transformer coil of a conventional aspect ratio tokamak reactor would be located in a high radiation environment but would be needed only during the initial discharge initiation and current ramp-up phases. Solenoid-free operation also provides greater flexibility in the selection of the aspect ratio and simplifies the reactor design. Plasma start-up methods based on induction from external poloidal field coils, helicity injection and radio frequency current drive have all made substantial progress towards meeting this important need for the ST. Some of these systems will now undergo the final stages of test in a new generation of large STs, which are scheduled to begin operations during the next two years. This paper reviews research to date on methods for inducing the initial start-up current in STs without reliance on the conventional central solenoid.

  13. Numerical modeling of the transition from low to high confinement in magnetically confined plasma

    Rasmussen, Jens Juul; Nielsen, Anders Henry; Madsen, Jens;


    The transition dynamics from low (L) to high (H) mode confinement in magnetically confined plasmas is investigated using a four-field drift fluid model—HESEL (Hot Edge-Sol-Electrostatic). The model includes profile evolution and is solved in a 2D domain at the out-board mid-plane of a tokamak......–I–H transition with an intermediate I-phase displaying limit-cycle oscillations (LCO). The model recovers the power threshold for the L–H transition, the scaling of the threshold with the density and with the loss-rate in the SOL, indicating a decrease in power threshold when switching from single to double null...

  14. Locality effects on bifurcation paradigm of L-H transition in tokamak plasmas

    Boonyarit Chatthong


    Full Text Available The locality effects on bifurcation paradigm of L-H transition phenomenon in magnetic confinement plasmas are investigated. One dimensional thermal transport equation with both neoclassical and anomalous transports effects included is considered, where a flow shear due to pressure gradient component is included as a transport suppression mechanism. Three different locally driven models for anomalous transport are considered, including a constant transport model, pressure gradient driven transport model, and critical pressure gradient threshold transport model. Local stability analysis shows that the transition occurs at a threshold flux with hysteresis nature only if ratio of anomalous strength over neoclassical transport exceeds a critical value. The depth of the hysteresis loop depends on both neoclassical and anomalous transports, as well as the suppression strength. The reduction of the heat flux required to maintain H-mode can be as low as a factor of two, which is similar to experimental evidence.

  15. Physics of Tokamak Plasma Start-up

    Mueller, Dennis


    This tutorial describes and reviews the state-of-art in tokamak plasma start-up and its importance to next step devices such as ITER, a Fusion Nuclear Science Facility and a Tokamak/ST demo. Tokamak plasma start-up includes breakdown of the initial gas, ramp-up of the plasma current to its final value and the control of plasma parameters during those phases. Tokamaks rely on an inductive component, typically a central solenoid, which has enabled attainment of high performance levels that has enabled the construction of the ITER device. Optimizing the inductive start-up phase continues to be an area of active research, especially in regards to achieving ITER scenarios. A new generation of superconducting tokamaks, EAST and KSTAR, experiments on DIII-D and operation with JET's ITER-like wall are contributing towards this effort. Inductive start-up relies on transformer action to generate a toroidal loop voltage and successful start-up is determined by gas breakdown, avalanche physics and plasma-wall interaction. The goal of achieving steady-sate tokamak operation has motivated interest in other methods for start-up that do not rely on the central solenoid. These include Coaxial Helicity Injection, outer poloidal field coil start-up, and point source helicity injection, which have achieved 200, 150 and 100 kA respectively of toroidal current on closed flux surfaces. Other methods including merging reconnection startup and Electron Bernstein Wave (EBW) plasma start-up are being studied on various devices. EBW start-up generates a directed electron channel due to wave particle interaction physics while the other methods mentioned rely on magnetic helicity injection and magnetic reconnection which are being modeled and understood using NIMROD code simulations.

  16. 30 Cool Facts about Mount St. Helens

    Driedger, Carolyn; Liz, Westby; Faust, Lisa; Frenzen, Peter; Bennett, Jeanne; Clynne, Michael


    Commemorating the 30th anniversary of the 1980 eruptions of Mount St. Helens 1-During the past 4,000 years, Mount St. Helens has erupted more frequently than any other volcano in the Cascade Range. 2-Most of Mount St. Helens is younger than 3,000 years old (younger than the pyramids of Egypt). 3-Some Native American names that refer to smoke at the volcano include- Lawala Clough, Low-We- Lat-Klah, Low-We-Not- Thlat, Loowit, Loo-wit, Loo-wit Lat-kla, and Louwala-Clough. 4-3,600 years ago-Native Americans abandoned hunting grounds devastated by an enormous eruption four times larger than the May 18, 1980 eruption. 5-1792-Captain George Vancouver named the volcano for Britain's ambassador to Spain, Alleyne Fitzherbert, also known as Baron St. Helens. 6-1975-U.S. Geological Survey geologists forecasted that Mount St. Helens would erupt again, 'possibly before the end of the century.' 7-March 20, 1980-A magnitude 4.2 earthquake signaled the reawakening of the volcano after 123 years. 8-Spring 1980-Rising magma pushed the volcano's north flank outward 5 feet per day. 9-Morning of May 18, 1980- The largest terrestrial landslide in recorded history reduced the summit by 1,300 feet and triggered a lateral blast. 10-Within 3 minutes, the lateral blast, traveling at more than 300 miles per hour, blew down and scorched 230 square miles of forest. 11-Within 15 minutes, a vertical plume of volcanic ash rose over 80,000 feet. 12-Afternoon of May 18, 1980-The dense ash cloud turned daylight into darkness in eastern Washington, causing streetlights to turn on in Yakima and Ritzville. 13-The volcanic ash cloud drifted east across the United States in 3 days and encircled Earth in 15 days. 14-Lahars (volcanic mudflows) filled rivers with rocks, sand, and mud, damaging 27 bridges and 200 homes and forcing 31 ships to remain in ports upstream. 15-The May 18, 1980 eruption was the most economically destructive volcanic event in U.S. history. 16-Small plants and trees beneath winter snow

  17. 妊娠相关蛋白A对老年急性冠状动脉综合征患者的预后价值%Prognostic value of pregnancy-associated plasma protein A in elderly patients with non-ST segment elevation acute coronary syndrome

    吴凡; 张蔷; 杜鑫; 张宜青; 万征


    Objective To study the prognostic value of pregnancy‐associated plasma protein‐A (PAPP‐A ) in elderly patients with NSTEACS .Methods Four hundred and fifty‐five elderly NSTEACS patients were included in this study .Their serum PAPP‐A level was measured .The patients were followed up for 12 months ,during which the adverse cardiovascular events were ob‐served .The patients were divided into high PAPP‐A group (n=147)and low PAPP‐A group (n=308) .The association between serum PAPP‐A level and adverse cardiovascular events was ana‐lyzed .Results At the end of 12 months follow‐up ,the incidence of combined endpoint events was significantly higher in high PAPP‐A group than in low PAPP‐A group (57 .7% vs 24 .4% ,P=0.000) .The sensitivity and specificity of PAPP‐A were 66 .7% and 75.0% for predicting adverse cardiovascular events when it was 23 .5 mU/L .The elevated PAPP‐A level was significantly asso‐ciated with adverse cardiovascular events (OR= 2 .832 ,P=0.006) .The elevated PAPP‐A level was an independent risk factor for poor prognosis (HR=2 .79 ,P=0 .007) .Conclusion PAPP‐A is an effective indicator of prognosis in elderly NSTEACS patients and can thus be used in assess‐ment of risk factors for their poor prognosis .%目的:评价妊娠相关蛋白A(PAPP‐A)对预测老年非ST段抬高急性冠状动脉综合征(NSTEACS)患者的预后临床价值。方法选择老年 NSTEACS 患者455例,测定外周血 PAPP‐A 水平,将患者分为高值组147例(PAPP‐A≥23.5 mU/L)和低值组308例(PAPP‐A <23.5 mU/L ),随访观察12个月不良心血管事件。分析PAPP‐A水平与不良心血管事件关系。结果随访12个月时,高值组复合终点事件发生率高于低值组(57.7% vs 24.4%,P=0.000)。PAPP‐A 界值23.5 mU/L 时,预测不良心血管事件敏感性为66.7%,特异性为75.0%。PAPP‐A升高与不良预后显著相关(OR=2.832

  18. Hot plasma dielectric tensor

    Westerhof, E.


    The hot plasma dielectric tensor is discussed in its various approximations. Collisionless cyclotron resonant damping and ion/electron Bernstein waves are discussed to exemplify the significance of a kinetic description of plasma waves.

  19. Special issue: Plasma Conversion

    Nozaki, T.; Bogaerts, A.; Tu, X.; van de Sanden, M. C. M.


    With growing concern of energy and environmental issues, the combination of plasma and heterogeneous catalysts receives special attention in greenhouse gas conversion, nitrogen fixation and hydrocarbon chemistry. Plasma gas conversion driven by renewable electricity is particularly important for the

  20. Development of High-Field ST Merging Experiment: TS-U for High Power Reconnection Heating

    Ono, Y.; Koike, H.; Tanabe, H.; Himeno, S.; Ishida, S.; Kimura, K.; Kawanami, M.; Narita, M.; Takahata, Y.; Yokoyama, T.; Inomoto, M.; Cheng, C. Z.


    We are developing high-magnetic field ST merging/ reconnection experiment TS-U with Brec = 0.3-0.5T, based on our scaling law of reconnection heating energy proportional to square of the reconnecting (poloidal) magnetic field Brec. This scaling law indicates that the high-Brec ST merging will heat ions to the burning plasma regime without using any additional heating facility. Its mechanism is that the reconnection outflow accelerates mainly ions up to the poloidal Alfven speed like the Sweet-Parker model. The shock-like density pileups thermalize the accelerated ions in the down-streams in agreement with recent solar satellite observations and PIC simulation results. We already documented significant ion heating of spheromak and ST mergings up to 0.25keV in TS-3 and 1.2keV in MAST, leading us to the high-Brec merging experiment TS-U. It is noted that high-resolution (>500 channel) 2D measurements of ion and electron temperatures is being developed for the purpose of solving all acceleration and heating effects of magnetic reconnection, such as the huge outflow heating of ions in the downstream and electron heating localized at the X-point.

  1. Introduction to Plasma Physics

    Gurnett, Donald A.; Bhattacharjee, Amitava


    Preface; 1. Introduction; 2. Characteristic parameters of a plasma; 3. Single particle motions; 4. Waves in a cold plasma; 5. Kinetic theory and the moment equations; 6. Magnetohydrodynamics; 7. MHD equilibria and stability; 8. Discontinuities and shock waves; 9. Electrostatic waves in a hot unmagnetized plasma; 10. Waves in a hot magnetized plasma; 11. Nonlinear effects; 12. Collisional processes; Appendix A. Symbols; Appendix B. Useful trigonometric identities; Appendix C. Vector differential operators; Appendix D. Vector calculus identities; Index.

  2. Plasma physics an introduction

    Fitzpatrick, Richard


    Plasma Physics: An Introduction is based on a series of university course lectures by a leading name in the field, and thoroughly covers the physics of the fourth state of matter. This book looks at non-relativistic, fully ionized, nondegenerate, quasi-neutral, and weakly coupled plasma. Intended for the student market, the text provides a concise and cohesive introduction to plasma physics theory, and offers a solid foundation for students wishing to take higher level courses in plasma physics.

  3. Von der Melkmaschine St. Pauli zu Utopia? St. Pauli selber machen!

    Steffen Jörg


    Full Text Available Das Interview mit Steffen Jörg vom Verein GWA (Gemeinwesenarbeit St. Pauli befasst sich mit den aktuellen Veränderungen in Hamburg St. Pauli. Es stellt sie in den Kontext der ,unternehmerischen Stadt’, die bereits seit den 1980er Jahren als Modell der Hamburger Stadtentwicklung gilt. Am Beispiel der kollektiven Proteste von Mieter_innen der inzwischen polizeilich geräumten ESSO-Häuser am Spielbudenplatz zeichnet Steffen Jörg das Bild von St. Pauli als einem umkämpften, aber auch widerspenstigen Stadtteil: Die Bewohner_innen artikulieren und organisieren sich immer deutlicher gegen die Vermarktung des Viertels und gegen eine eindimensional renditeorientierte Stadtentwicklung für Besserverdienende, mit der eine Verdrängung armer Mieter_innen und Kleingewerbestrukturen verbunden ist. 

  4. The role of mitochondrial fusion and StAR phosphorylation in the regulation of StAR activity and steroidogenesis.

    Castillo, Ana F; Orlando, Ulises; Helfenberger, Katia E; Poderoso, Cecilia; Podesta, Ernesto J


    The steroidogenic acute regulatory (StAR) protein regulates the rate-limiting step in steroidogenesis, i.e. the delivery of cholesterol from the outer (OMM) to the inner (IMM) mitochondrial membrane. StAR is a 37-kDa protein with an N-terminal mitochondrial targeting sequence that is cleaved off during mitochondrial import to yield 30-kDa intramitochondrial StAR. StAR acts exclusively on the OMM and its activity is proportional to how long it remains on the OMM. However, the precise fashion and the molecular mechanism in which StAR remains on the OMM have not been elucidated yet. In this work we will discuss the role of mitochondrial fusion and StAR phosphorylation by the extracellular signal-regulated kinases 1/2 (ERK1/2) as part of the mechanism that regulates StAR retention on the OMM and activity.

  5. Plasma membrane ATPases

    Palmgren, Michael Broberg; Bækgaard, Lone; Lopez Marques, Rosa Laura


    The plasma membrane separates the cellular contents from the surrounding environment. Nutrients must enter through the plasma membrane in order to reach the cell interior, and toxic metabolites and several ions leave the cell by traveling across the same barrier. Biological pumps in the plasma me...

  6. Plasma in dentistry

    Cha, Seunghee; Park, Young-Seok


    This review describes the contemporary aspects of plasma application in dentistry. Previous studies on plasma applications were classified into two categories, surface treatment and direct applications, and were reviewed, respectively according to the approach. The current review discussed modification of dental implant surface, enhancing of adhesive qualities, enhancing of polymerization, surface coating and plasma cleaning under the topics of surface treatment. Microbicidal activities, deco...

  7. The Plasma Universe

    Suplee, Curt


    Preface; 1. The fourth state of matter; 2. The music and dance of plasmas; 3. The Sun-Earth connection; 4. Bringing the Sun to Earth: the story of controlled thermonuclear fusion; 5. The cosmic plasma theater: galaxies, stars, and accretion disks; 6. Putting plasmas to work; Index.

  8. Selective Etching of Semicrystalline Polymers: CF4 Gas Plasma Treatment of Poly(ethylene)

    Olde Riekerink, M.B.; Terlingen, J.G.A.; Engbers, G.H.M.; Feijen, J.


    A series of poly(ethylene) (PE) films with different degrees of crystallinity was treated with a radio-frequency tetrafluoromethane (CF4) gas plasma (48-49 W, 0.06-0.07 mbar, and continuous vs pulsed treatment). The etching behavior and surface chemical and structural changes of the PE films were st

  9. Cyclotron waves in plasma

    Lominadze, D G


    Cyclotron Waves in Plasma is a four-chapter text that covers the basic physical concepts of the theory of cyclotron waves and cyclotron instabilities, brought about by the existence of steady or alternating plasma currents flowing perpendicular to the magnetic field.This book considers first a wide range of questions associated with the linear theory of cyclotron oscillations in equilibrium plasmas and in electron plasmas in metals and semiconductors. The next chapter deals with the parametric excitation of electron cyclotron oscillations in plasma in an alternating electric field. A chapter f

  10. Continuous plasma perfusion of dual cartridges in series: rationale and early clinical experience.

    Sun, Liang; Yan, Peng-Bo; Zhang, Yu-Hua; Wei, Lu-Qing; Li, Guo-Qiang


    To improve the efficiency of plasma perfusion on eliminating plasma paraquat (PQ), we designed continuous plasma perfusion of dual cartridges in series (CPPDCS) on Diapact Braun CRRT machine. The goals of this study were to evaluate the effective of CPPDCS on paraquat removal in patients with acute paraquat intoxication. Our results show that the PQ clearance rate of dual cartridges was significantly higher than that of single cartridge at 1st, 2nd, 3(rd), and 4th plasma perfusion. Compared with single-cartridge plasma perfusion, CPPDCS significantly reduced the frequency of cartridge replacement, shorten the time of perfusion. These results indicate that CPPDCS is effective than plasma perfusion of single cartridge on PQ clearance rate and may provide an effective treatment for PQ poisoning.

  11. 31st IMAC Conference on Structural Dynamics

    Adams, Douglas; Carrella, Alex; Mayes, Randy; Rixen, Daniel; Allen, Matt; Cunha, Alvaro; Catbas, Fikret; Pakzad, Shamim; Racic, Vitomir; Pavic, Aleksandar; Reynolds, Paul; Simmermacher, Todd; Cogan, Scott; Moaveni, Babak; Papadimitriou, Costas; Allemang, Randall; Clerck, James; Niezrecki, Christopher; Wicks, Alfred


    Topics in Nonlinear Dynamics, Volume 1: Proceedings of the 31st IMAC, A Conference and Exposition on Structural Dynamics, 2013, the first volume of seven from the Conference, brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Structural Dynamics, including papers on:   Nonlinear Oscillations Nonlinearities In Practice Nonlinear System Identification: Methods Nonlinear System Identification: Friction & Contact Nonlinear Modal Analysis Nonlinear Modeling & Simulation Nonlinear Vibration Absorbers Constructive Utilization of Nonlinearity.

  12. ST Elevation Myocardial Infarction in the elderly

    Marcelo Franken; Amit Nussbacher; Alberto Liberman; Mauricio Wajngarten


    Acute coronary syndromes (ACS) are the leading causes of death in the elderly. The suspicion and diagnosis of ACS in this age group is more difficult, since typical angina is less frequent. The morbidity and mortality is greater in older age patients presenting ACS. Despite the higher prevalence and greater risk, elderly patients are underrepresented in major clinical trials from which evidence based recommendations are formulated. The authors describe, in this article, the challenges in the diagnosis and management of ST elevation myocardial infarction in the elderly, and discuss the available evidence.

  13. 21st Century South African Science Fiction



    Full Text Available The paper analyses some aspects of South African science fiction, starting with its beginnings in the 1920s and focusing on some 21st century writings. Thus Lauren Beukes’ novels Moxyland (2008 and Zoo City (2010 are taken into consideration in order to present new trends in South African literature and the way science fiction has been marked by Apartheid. The second South African science fiction writer whose writings are examined is Henrietta Rose-Innes (with her novel Nineveh, published in 2011 as this consolidates women's presence in the SF world.

  14. Plan de negocios del proyecto "ST. Marcus"

    Yépez Hidalgo, Patricia Alejandra


    The present work is a Business Plan Project "ST. Marcus ", located in the Valley of Cumbayá, in the La Primavera, consists of 112 apartments, consisting of suites and apartments of 2 and 3 bedrooms, four 6-story towers. It features spacious communal areas, gardens, pool, terraces, equipped gymnasium, squash court, meeting rooms, hotel lobby kind of luxury. Constructum S.A. a company with 20 year’s experience in real estate projects intends to invest in this project for profitability for th...

  15. Health Physics in the 21st Century

    Bevelacqua, Joseph John


    Adopting a proactive approach and focusing on emerging radiation-generating technologies, Health Physics in the 21st Century meets the growing need for a presentation of the relevant radiological characteristics and hazards. As such, this monograph discusses those technologies that will affect the health physics and radiation protection profession over the decades to come. After an introductory overview, the second part of this book looks at fission and fusion energy, followed by a section devoted to accelerators, while the final main section deals with radiation on manned space missions.

  16. Water resources of St. Helena Parish, Louisiana

    White, Vincent E.; Prakken, Lawrence B.


    Information concerning the availability, use, and quality of water in St. Helena Parish, Louisiana, is critical for proper water-resource management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. Information on the availability, past and current use, use trends, and water quality from groundwater and surface-water sources in the parish is presented. Previously published reports and data stored in the U.S. Geological Survey’s National Water Information System ( are the primary sources of the information presented here.

  17. Project StORe: Social Science report

    Burton, Guy


    There was widespread support across the social science research community regarding the aims of the StORe Project Nearly half of social science respondents claimed that both source-to-output and out-put-to source repositories would offer a ‘significant advantage to my work’; a third in both cases claimed it would be ‘useful but not of major significance’ Postgraduate students were generally more enthusiastic about source-to-output and output-to-source repositories than acade...

  18. Ambulatory ST segment monitoring after myocardial infarction

    Mickley, H


    as important reasons for the inconsistent findings. The precise role of ambulatory ST segment monitoring in clinical practice has yet to be established. Direct comparisons with exercise stress testing may not be appropriate for two reasons. Firstly, the main advantage of ambulatory monitoring may...... ischaemia provides prognostic information in different subsets of patients with previous myocardial infarction, but there is considerable disagreement about how this is expressed in terms of cardiac events. Small patient numbers, patient selection, and different timing of ambulatory monitoring are proposed...

  19. Plasma Therapy: An Overview

    Rajkumar Diwan


    Full Text Available Definition: Plasma, the fourth state of matter, is a collection of charged particles (electrons, ions, neutral atoms. Recent demonstration of plasma technology in treatment of living cells, tissue and organs are creating a new field at the intersection of plasma science and technology with biology and medicine known as plasma medicine. Plasma medicine is one of the newest fields of modem applied plasma chemistry. It appeared several years ago and comprises studies concerning the direct action of low-temperature, one atmosphere air plasma (cold plasma/nonthermal plasmalnonequilibrium on body tissues for various noninvasive therapeutic treatments or diagnostics purpose. The study of plasma holds promise for a myriad of applications ranging from lasers and electronics, hazardous decontamination, sterilization and disinfection of foods, soil, water, instruments, to medical uses in wound healing and treating certain types of tumors and cancers. Plasma represents a new state-of-the-art sterilization and disinfection treatment for certain oral and environmental pathogens, heat-sensitive materials, hard and soft surfaces, and may assist health care facilities in the management of various health concerns. The role that low temperature atmospheric pressure plasma (LTAPP could play in the inactivation of pathogenic microorganisms might prove to be a new, faster, more economical alternative.

  20. Roles of Plasmalemma Aquaporin Gene StPIP1 in Enhancing Drought Tolerance in Potato

    Junlian Zhang


    Full Text Available Survival and mortality of plants in response to severe drought may be related to carbon starvation, but little is known about how plasma membrane intrinsic proteins may help alleviate the drought-induced damage. Here, we determined the roles of plasmalemma aquaporin gene in improving plant water status, maintaining carbon accumulation, and thereby enhancing drought tolerance. Seven StPIP1 transformed potato (Solanum tuberosum L. lines (namely T1, T2…T7 were compared with non-transgenic control plant at molecule and whole-plant levels. The relative expression of StPIP1 gene was found in leaves, stems and roots, with the most abundant expression being in the roots. The transgenic lines T6 and T7 had the highest StPIP1 expression, averaging 7.2 times that of the control and the greatest differences occurred 48 h after mannitol osmotic stress treatment. Using an evaluation index to quantifying the degree of drought tolerance, we found that the StPIP1 transgenic lines T6 and T7 had the highest drought tolerance, averaging 8.5 times that of the control. Measured at 30 days in drought stress treatment, the control plant decreased net photosynthetic rate by 33 and 56%, respectively, under moderate and severe stresses; also decreased stomatal conductance by 39 and 65%; and lowered transpiration rate by 49 and 69%, compared to the no-stress treatment, whereas the transgenic lines T6 and T7 maintained a relatively stable level with slight decreases in these properties. The constitutive overexpression of StPIP1 in potato improved plant water use efficiency and increased nonstructural carbohydrate concentration, which helped alleviate carbon starvation and minimized the loss of biomass and tuber yield due to drought stress. We conclude that the expression of StPIPs improves overall water relations in the plant and helps maintain photosynthesis and stomatal conductance; these help minimize carbon starvation and enhance the whole plant tolerance to drought

  1. Arc Plasma Torch Modeling

    Trelles, J P; Vardelle, A; Heberlein, J V R


    Arc plasma torches are the primary components of various industrial thermal plasma processes involving plasma spraying, metal cutting and welding, thermal plasma CVD, metal melting and remelting, waste treatment and gas production. They are relatively simple devices whose operation implies intricate thermal, chemical, electrical, and fluid dynamics phenomena. Modeling may be used as a means to better understand the physical processes involved in their operation. This paper presents an overview of the main aspects involved in the modeling of DC arc plasma torches: the mathematical models including thermodynamic and chemical non-equilibrium models, turbulent and radiative transport, thermodynamic and transport property calculation, boundary conditions and arc reattachment models. It focuses on the conventional plasma torches used for plasma spraying that include a hot-cathode and a nozzle anode.

  2. Laminar Plasma Dynamos

    Wang, Z; Barnes, C W; Barnes, D C; Wang, Zhehui; Pariev, Vladimir I.; Barnes, Cris W.; Barnes, Daniel C.


    A new kind of dynamo utilizing flowing laboratory plasmas has been identified. Conversion of plasma kinetic energy to magnetic energy is verified numerically by kinematic dynamo simulations for magnetic Reynolds numbers above 210. As opposed to intrinsically-turbulent liquid-sodium dynamos, the proposed plasma dynamos correspond to laminar flow topology. Modest plasma parameters, 1-20 eV temperatures, 10^{19}-10^{20} m^{-3} densities in 0.3-1.0 m scale-lengths driven by velocities on the order of the Alfven Critical Ionization Velocity (CIV), self-consistently satisfy the conditions needed for the magnetic field amplication. Growth rates for the plasma dynamos are obtained numerically with different geometry and magnetic Reynolds numbers. Magnetic-field-free coaxial plasma guns can be used to sustain the plasma flow and the dynamo.

  3. Plasma polymerization by Softplasma

    Jiang, J.; Wu, Zhenning; Benter, Maike


    In the late 19th century, the first depositions - known today as plasma polymers, were reported. In the last century, more and more research has been put into plasma polymers. Many different deposition systems have been developed. [1, 2] Shi F. F. broadly classified them into internal electrode......, external electrode, and electrodeless microwave or high frequency reactors. [3] Softplasma™ is an internal electrode plasma setup powered by low frequenc~ gower supply. It was developed in late 90s for surface treatment of silicone rubber. [ ]- 5] It is a low pressure, low electron density, 3D homogenous...... plasma. In this study, we are presenting the surface modification"pf polymers by plasma polymerization using Softplasma™. Softplasma™ can be used for two major types of polymerization: polymerization of vinyl monomers, where plasma acts as initiator; chemical vapour deposition, where plasma acts...

  4. Serum Copper and Plasma Protein Status in Normal Pregnancy

    Nushrat Noor, Nasim Jahan, Nayma Sultana


    Full Text Available AbstractBackground: Gradual alteration of serum copper and some plasma protein levels may occur with advancement of pregnancy, which is associated with increased maternal and infant morbidity and mortality.Objective: To observe serum copper and plasma protein levels in normal pregnant women of different trimesters in order to find out their nutritional status.Methods: This cross sectional study was carried out in the Department of Physiology, Sir Salimullah Medical College (SSMC, Dhaka, between 1st January 2010 and December 2010. Ninety normal pregnant women of different trimesters with age 20-30 years were included in the study group. They were selected from Out Patient Department of Obstetrics and Gynaecology, SSMC. Age matched 30 non-pregnant women were taken as control. Serum copper level was measured by Spectrophotometric method, serum total protein and albumin levels were estimated by standard method. Statistical analysis was done by one way ANOVA, Bonferroni and Pearson’s correlation coefficient test as applicable.Results: Serum Cu levels were significantly higher in all trimesters of pregnant women compared to control. Again, this value was significantly higher in 3rd trimester than that of in 1st and 2nd trimester and also in 2nd trimester than that of in 1st trimester. In addition, mean serum total protein level was significantly lower in 3rd trimester than control but no statistically significant difference was observed among different trimesters. Again, mean serum albumin level was significantly lower in 2nd and 3rd trimester than 1st trimester and control. In addition, serum Cu concentration showed significant positive correlation with different trimesters of gestation.Conclusion: This study reveals that hypercupremia along with hypoproteinemia occur in pregnant women from 1st to 3rd trimester of gestation. This gradual alteration of micro and macronutrients become more profound with advancement of pregnancy.

  5. On plasma convection in Saturn's magnetosphere

    Livi, Roberto

    10-19 RS and from July 1st, 2004 to . Hot electron densities peak near 9 RS and decrease radially at a rate of 1/r3, which suggests a source in the inner magnetosphere. We also observe a decrease in electron energy at a rate of 1/r3 due to the conservation of the first adiabatic invariant, consistent with radial transport through a magnetic dipole. Data from the magnetic field instrument is used to derive the magnetic moment of hot electrons which shows a constant value of 103.4 kgm2s-2 nT-1 +/-10 between 10-19 RS, indicating a loss-free adiabatic transport with minor fluctuations. Plasma transport at Saturn can occur through flux tube interchange instabilities within the magnetosphere, where cold dense plasma is transported radially outward while hot tenuous plasma from the outer magnetosphere moves radially inward. Gradient-curvature drifts cause these hot electrons leave the injection and superimpose on the ambient cold plasma, consequently forcing it to move radially outward. This implies flux-tube interchange to be the main source for hot electrons. Hot electrons are part of the plasma analysis for which CAPS was designed, while the MIMI-LEMMS instrument measures higher energy electrons. Taking into account the penetrating background radiation, we are able to derive information for these energetic particles using our plasma instruments. We present CAPS-IMS background measurements derived from plasma data and show strong correlation with high energy particle data from MIMI-LEMMS. IMS background is generated via two main processes: 1) Collisions between the instrument walls and ambient energetic particles, which cause X-rays to trigger count signals in the instrument optics, and 2) backscatter of energetic particles in the electrostatic analyzer. We quantify these effects and use the results to identify Saturn's radiation belt peaks and nadirs, and magnetospheric regions of depleted particle fluxes, or microsignatures, which are formed through interactions with

  6. Plasmas for medicine

    von Woedtke, Th.; Reuter, S.; Masur, K.; Weltmann, K.-D.


    Plasma medicine is an innovative and emerging field combining plasma physics, life science and clinical medicine. In a more general perspective, medical application of physical plasma can be subdivided into two principal approaches. (i) “Indirect” use of plasma-based or plasma-supplemented techniques to treat surfaces, materials or devices to realize specific qualities for subsequent special medical applications, and (ii) application of physical plasma on or in the human (or animal) body to realize therapeutic effects based on direct interaction of plasma with living tissue. The field of plasma applications for the treatment of medical materials or devices is intensively researched and partially well established for several years. However, plasma medicine in the sense of its actual definition as a new field of research focuses on the use of plasma technology in the treatment of living cells, tissues, and organs. Therefore, the aim of the new research field of plasma medicine is the exploitation of a much more differentiated interaction of specific plasma components with specific structural as well as functional elements or functionalities of living cells. This interaction can possibly lead either to stimulation or inhibition of cellular function and be finally used for therapeutic purposes. During recent years a broad spectrum of different plasma sources with various names dedicated for biomedical applications has been reported. So far, research activities were mainly focused on barrier discharges and plasma jets working at atmospheric pressure. Most efforts to realize plasma application directly on or in the human (or animal) body for medical purposes is concentrated on the broad field of dermatology including wound healing, but also includes cancer treatment, endoscopy, or dentistry. Despite the fact that the field of plasma medicine is very young and until now mostly in an empirical stage of development yet, there are first indicators of its enormous

  7. Nonlinear Plasma Wave in Magnetized Plasmas

    Bulanov, Sergei V; Kando, Masaki; Koga, James K; Hosokai, Tomonao; Zhidkov, Alexei G; Kodama, Ryosuke


    Nonlinear axisymmetric cylindrical plasma oscillations in magnetized collisionless plasmas are a model for the electron fluid collapse on the axis behind an ultrashort relativisically intense laser pulse exciting a plasma wake wave. We present an analytical description of the strongly nonlinear oscillations showing that the magnetic field prevents closing of the cavity formed behind the laser pulse. This effect is demonstrated with 3D PIC simulations of the laser-plasma interaction. An analysis of the betatron oscillations of fast electrons in the presence of the magnetic field reveals a characteristic "Four-Ray Star" pattern which has been observed in the image of the electron bunch in experiments [T. Hosokai, et al., Phys. Rev. Lett. 97, 075004 (2006)].

  8. Differentiating ST elevation myocardial infarction and nonischemic causes of ST elevation by analyzing the presenting electrocardiogram

    Jayroe, Jason B; Spodick, David H; Nikus, Kjell;


    Guidelines recommend that patients with suggestive symptoms of myocardial ischemia and ST-segment elevation (STE) in > or =2 adjacent electrocardiographic leads should receive immediate reperfusion therapy. Novel strategies aimed to reduce door-to-balloon time, such as prehospital wireless electr...

  9. Outbreak of KPC-3-producing ST15 and ST348 Klebsiella pneumoniae in a Portuguese hospital.

    Vubil, D; Figueiredo, R; Reis, T; Canha, C; Boaventura, L; DA Silva, G J


    To date, only a few sporadic cases of infections due to Klebsiella pneumoniae carbapenemase (KPC) producers have been reported in Portugal. Here, we report for the first time an outbreak of K. pneumoniae KPC-3 producers in a tertiary-care hospital during 2013. Twenty-seven ertapenem-resistant K. pneumoniae were identified in patients at a tertiary-care hospital during 2013 isolated predominantly from urine (48·1%) and blood (25·9%) cultures. All isolates were highly resistant to β-lactam antibiotics and most showed intermediate resistance to imipenem. The more frequent β-lactamases were TEM- (77·7%), CTX-M- (70·3%) and KPC-type (66·6%). KPC-3 was identified by sequencing. The bla KPC-3 gene was associated with an IncF plasmid, and efficiently transferred to E. coli J53. Pulsed-field gel electrophoresis typing revealed three clusters of isolates which were further characterized by multi-locus sequence typing as ST11, ST15 and ST348. Ertapenem-resistant ST15 was already in circulation in the hospital, related to expression of OmpK36 modified porin, but the other two sequence types had not been previously found in the hospital. We conclude that the IncF plasmid mediated transfer of KPC-3 in the outbreak and that implementation of carbapenemase gene screening in isolates from patients on admission to hospital is advisable in order to control dissemination of these antimicrobial resistance elements.

  10. Principal Component Surface (2011) for St. Thomas East End Reserve, St. Thomas

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 0.3x0.3 meter principal component analysis (PCA) surface for areas the St. Thomas East End Reserve (STEER) in the U.S. Virgin Islands (USVI)....

  11. Electron transport in the plasma edge with rotating resonant magnetic perturbations at the TEXTOR tokamak

    Stoschus, Henning


    Small three-dimensional (3D) magnetic perturbations can be used as a tool to control the edge plasma parameters in magnetically confined plasmas in high confinement mode (''H-mode'') to suppress edge instabilities inherent to this regime, the Edge Localized Modes (ELMs). In this work, the impact of rotating 3D resonant magnetic perturbation (RMP) fields on the edge plasma structure characterized by electron density and temperature fields is investigated. We study a low confinement (L-mode) edge plasma (r/a>0.9) with high resistivity (edge electron collisionality {nu}{sup *}{sub e}>4) at the TEXTOR tokamak. The plasma structure in the plasma edge is measured by a set of high resolution diagnostics: a fast CCD camera ({delta}t=20 {mu}s) is set up in order to visualize the plasma structure in terms of electron density variations. A supersonic helium beam diagnostic is established as standard diagnostic at TEXTOR to measure electron density n{sub e} and temperature T{sub e} with high spatial ({delta}r=2 mm) and temporal resolution ({delta}t=20 {mu}s). The measured plasma structure is compared to modeling results from the fluid plasma and kinetic neutral transport code EMC3-EIRENE. A sequence of five new observations is discussed: (1) Imaging of electron density variations in the plasma edge shows that a fast rotating RMP field imposes an edge plasma structure, which rotates with the external RMP rotation frequency of vertical stroke {nu}{sub RMP} vertical stroke =1 kHz. (2) Measurements of the electron density and temperature provide strong experimental evidence that in the far edge a rotating 3D scrape-off layer (SOL) exists with helical exhaust channels to the plasma wall components. (3) Radially inward, the plasma structure at the next rational flux surface is found to depend on the relative rotation between external RMP field and intrinsic plasma rotation. For low relative rotation the plasma structure is dominated by a particle and energy loss

  12. Pluralism and Longstanding Value of S&T Development


    With the strategic opportunities brought about by the current S&T revolution, new and higher requirements have been set for the S&T system so as to accelerate the transformation of the economic growth mode with S&T development.In 2009, the CAS Academic Divisions (CASAD) Committee of Consultation and Evaluation formed a research panel to examine how to enable China's S&T system and policies to fit the needs of strategic development in the new era.The panel conducted a survey of S&T workers and administrators, with questionnaire covering issues raised by CAS Members and other experts.Then, on the basis of findings from symposia and the survey, the research team analyzed deep-seated mechanism and policy problems concerning China's current and longstanding S&T development.

  13. The cognitive status of stød

    Clausen, Sara Juul; Kristensen, Line Burholt


    The Danish prosodic phenomenon stød is associated with a specific range of suffixes including the singular definite suffixes -en and -et. Diachronically, as well as distributionally, stød is related to Swedish/Norwegian accent 1, but unlike accent 1, stød is seen as phonetically and phonologically...... marked. Keeping in mind the cross-distribution between phonetic/phonological markedness and distributional patterns, we investigate here whether stød is also related to accent 1 when it comes to cognitive markedness. We present the results of a psycholinguistic study in which participants attended...... to words that were either appropriate combinations of prosody (stød vs. non-stød) and suffix (singular definite -en/-et vs. plural indefinite -e) or mismatches between prosody and suffix. Participants gave slower and more inaccurate responses to mismatches. This effect of mismatch was most pronounced...


    Groupes ST-EL, ST-TFM, ST-CV


    The electricity, cooling and ventilation system cut notices of the ST division are now available on the Web via a pilot project EDMS from the Home Page of the ST Division: proposed structure can be subject to modifications; a search system for the notices is under study by the EDMS team and will be installed before Christmas.The paper distribution of the notices is now replaced by electronic message system. All persons subscribed to the existing distribution lists will receive e-mail with notices attached.For additional information or remarks, please send e-mail to, ST-TFM, ST-CV Groups

  15. Knowledge society in 21st century

    Martina Urbanová


    Full Text Available This paper is focused on the increasing need of education in 21st century and on some problems which emerged in this context – the economists prefer to emphasize the development and growth, profit and effectiveness, and they can overlook general, ethical, and essential problems and needs of the contemporary world. These problems are not resolved by simple algometrical approaches, but they require multi-disciplined paradigms, which can provide social sciences.Especially in the 21st century we need wide-ranging critical thinking as a basis of responsible ethical behaviour. However in the current educational environment in the tertiary educational system we can observe over-emphasizing of utilitarian requirements. We produce professionals who are expected to be able to find quick, effective but also far-seeing solutions of any given problem, which is in obvious contradiction. This article discussed three conceptions of a human with the emphasis on the concept of “homo socio-oeconomicus”. This concept enables to see the world in wide context and develops necessary critical thinking, which is also economically more advantageous from the long-term point of view. That is why education in sociological, psychological, philosophical, political and other social sciences should not be considered by economists as something useless without any economic value, but as something that can help them to understand themselves, their environment and the consequences of their decisions. This is the core of this contribution.

  16. Retendering of ST-CV maintenance contract

    Battistin, M


    During the next three years, the ST/CV group will be deeply involved in the installation works for the LHC project. During this period the need for maintenance activity will decrease. The minimum level will be reached during the “long shutdown” of the PS and SPS machines in 2005. The budget for the maintenance will decrease accordingly, thus the CV group had to review its maintenance strategy. The new contract, which started on January 1st 2003, has been defined to cope with these workload variations during the next years and to guarantee the minimum maintenance activity on the existing equipment. A lump-sum contract based on a win-win strategy has been discarded. The contractor no longer has to guarantee the performance of the CERN cooling and ventilation systems. A new price list strategy based on performance indicators and penalties has been chosen. The contractor now has to guarantee the performance of every maintenance operation demanded by CERN. This modification obliged the Operation section of the...

  17. Nursing heroism in the 21st Century'

    Darbyshire Philip


    Full Text Available Abstract Background The Vivian Bullwinkel Oration honours the life and work of an extraordinary nurse. Given her story and that of her World War II colleagues, the topic of nursing heroism in the 21st century could not be more germane. Discussion Is heroism a legitimate part of nursing, or are nurses simply 'just doing their job' even when facing extreme personal danger? In this paper I explore the place and relevance of heroism in contemporary nursing. I propose that nursing heroism deserves a broader appreciation and that within the term lie many hidden, 'unsung' or 'unrecorded' heroisms. I also challenge the critiques of heroism that would condemn it as part of a 'militarisation' of nursing. Finally, I argue that nursing needs to be more open in celebrating our heroes and the transformative power of nursing achievements. Summary The language of heroism may sound quaint by 21st Century standards but nursing heroism is alive and well in the best of our contemporary nursing ethos and practice.

  18. Federal laboratories for the 21st century

    Gover, J. [Sandia National Labs., Albuquerque, NM (United States); Huray, P.G. [Univ. of South Carolina, Columbia, SC (United States)


    Federal laboratories have successfully filled many roles for the public; however, as the 21st Century nears it is time to rethink and reevaluate how Federal laboratories can better support the public and identify new roles for this class of publicly-owned institutions. The productivity of the Federal laboratory system can be increased by making use of public outcome metrics, by benchmarking laboratories, by deploying innovative new governance models, by partnerships of Federal laboratories with universities and companies, and by accelerating the transition of federal laboratories and the agencies that own them into learning organizations. The authors must learn how government-owned laboratories in other countries serve their public. Taiwan`s government laboratory, Industrial Technology Research Institute, has been particularly successful in promoting economic growth. It is time to stop operating Federal laboratories as monopoly institutions; therefore, competition between Federal laboratories must be promoted. Additionally, Federal laboratories capable of addressing emerging 21st century public problems must be identified and given the challenge of serving the public in innovative new ways. Increased investment in case studies of particular programs at Federal laboratories and research on the public utility of a system of Federal laboratories could lead to increased productivity of laboratories. Elimination of risk-averse Federal laboratory and agency bureaucracies would also have dramatic impact on the productivity of the Federal laboratory system. Appropriately used, the US Federal laboratory system offers the US an innovative advantage over other nations.

  19. Simple predictive electron transport models applied to sawtoothing plasmas

    Kim, D.; Merle, A.; Sauter, O.; Goodman, T. P.


    In this work, we introduce two simple transport models to evaluate the time evolution of electron temperature and density profiles during sawtooth cycles (i.e. over a sawtooth period time-scale). Since the aim of these simulations is to estimate reliable profiles within a short calculation time, two simplified ad-hoc models have been developed. The goal for these models is to rely on a few easy-to-check free parameters, such as the confinement time scaling factor and the profiles’ averaged scale-lengths. Due to the simplicity and short calculation time of the models, it is expected that these models can also be applied to real-time transport simulations. We show that it works well for Ohmic and EC heated L- and H-mode plasmas. The differences between these models are discussed and we show that their predictive capabilities are similar. Thus only one model is used to reproduce with simulations the results of sawtooth control experiments on the TCV tokamak. For the sawtooth pacing, the calculated time delays between the EC power off and sawtooth crash time agree well with the experimental results. The map of possible locking range is also well reproduced by the simulation.

  20. Boosting 21st Century Skills through Moroccan ELT Textbooks

    Hassan Ait Bouzid


    Research shows that the changing realities of the 21st century necessitate a fundamental shift in language education towards promoting 21st Century Skills. This paper investigates the extent to which three Moroccan ELT textbooks currently used in teaching second year Baccalaureate students in public high school provide activities that help learners build skills that match the needs of the 21st century. It also explores the types of activities that are used to promote these skills and eventual...

  1. Chicago-St. Louis high speed rail plan

    Stead, M.E.


    The Illinois Department of Transportation (IDOT), in cooperation with Amtrak, undertook the Chicago-St. Louis High Speed Rail Financial and Implementation Plan study in order to develop a realistic and achievable blueprint for implementation of high speed rail in the Chicago-St. Louis corridor. This report presents a summary of the Price Waterhouse Project Team`s analysis and the Financial and Implementation Plan for implementing high speed rail service in the Chicago-St. Louis corridor.

  2. Frauen mit Eßstörungen im Ausdauersport

    Bös, Annette


    Die vorliegende Arbeit untersucht das Phänomen Eßstörungen bei Ausdauersportlerinnen. Auf dem Hintergrund des identitätstheoretischen Ansatzes von Stahr et al. (1995) geht es um die Frage nach den Hauptverursachungsmomenten der Eßstörungen von sieben jungen Sportlerinnen. Im Rahmen einer qualitativen Sozialforschungsarbeit wurden sieben Athletinnen in einem problemzentrierten Interview zur Phase ihrer Eßstörungserkrankung befragt. Die Arbeit setzt sich zum Ziel, einen Beitrag zur systematisch...

  3. St. George at Prague Castle and Perseus: an Impossible Encounter?

    Bažant, J. (Jan)


    St. George and Perseus crossed their paths for the first time in the 11th century when the myth of Greek hero inspired the legend of a Christian saint. In the 14th century, the pictorial types of St. George, Perseus and Bellerphon fighting the dragon started converging. The famous bronze statue of St. George at the Prague Castle, which was creted in 1373, represents an advanced stage opf the process.

  4. Real-time wavelet detection of crashes in limit cycles of non-stationary fusion plasmas

    Berkel, M. van, E-mail: [Eindhoven University of Technology, Department of Mechanical Engineering, Control Systems Technology Group, PO Box 513, 5600 MB Eindhoven (Netherlands); FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Trilateral Euregio Cluster, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Witvoet, G.; Baar, M.R. de [Eindhoven University of Technology, Department of Mechanical Engineering, Control Systems Technology Group, PO Box 513, 5600 MB Eindhoven (Netherlands); FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Trilateral Euregio Cluster, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Nuij, P.W.J.M. [Eindhoven University of Technology, Department of Mechanical Engineering, Control Systems Technology Group, PO Box 513, 5600 MB Eindhoven (Netherlands); Morsche, H.G. ter [Eindhoven University of Technology, Department of Mathematics and Computer Science, PO Box 513, 5600 MB Eindhoven (Netherlands); Steinbuch, M. [Eindhoven University of Technology, Department of Mechanical Engineering, Control Systems Technology Group, PO Box 513, 5600 MB Eindhoven (Netherlands)


    Highlights: Black-Right-Pointing-Pointer We propose a new wavelet-based method for accurate and robust detection of limit cycle crashes in fusion plasmas. Black-Right-Pointing-Pointer The method is optimized for real-time applications such that it has small delay. Black-Right-Pointing-Pointer The method is implemented in a real-time algorithm and is tested on experimental data. Black-Right-Pointing-Pointer Almost all crashes are detected flawlessly including off-waveforms with high SNR. - Abstract: The high performance mode (H-mode) is one of the baseline plasma scenarios for the experimental fusion reactor ITER. This scenario features a periodic crash-like reorganization of the plasma pressure and the magnetic flux in the plasma core and plasma periphery. The core instability is often referred to as the sawtooth instability while the instability at the edge of the plasma is referred to as ELM. In this paper we present an algorithm for optimized (low latency, robust and high fidelity) real-time sensing of the crashes. The algorithm is based on time-scale wavelet theory and edge-detection. It is argued that detection of crashes has considerably less delay than the other methods. The realized accuracy of the detection algorithm is well below the uncertainty of the crash period for most crashes. Multiresolution analysis enables distinction between different sizes of sawtooth crashes due to the different sizes of wavelets (scales), resulting in an algorithm, which is robust and accurate. Although strictly speaking, the crash detection method is demonstrated for sawteeth measured with ECE only, it can be applied to any periodic crash, measured with any temporally resolved data. Note that the possibility of differentiating between crash like events of different nature depends on their individual time-scales and used measurement setup.

  5. The cognitive status of stød

    Clausen, Sara Juul; Kristensen, Line Burholt


    The Danish prosodic phenomenon stød is associated with a specific range of suffixes including the singular definite suffixes -en and -et. Diachronically, as well as distributionally, stød is related to Swedish/Norwegian accent 1, but unlike accent 1, stød is seen as phonetically and phonologically...... marked. Keeping in mind the cross-distribution between phonetic/phonological markedness and distributional patterns, we investigate here whether stød is also related to accent 1 when it comes to cognitive markedness. We present the results of a psycholinguistic study in which participants attended...

  6. Injury Prevention and Performance Enhancement in 101st Airbourne Soldiers


    Crawford K, Darnell ME, Abt JP, Sell TC, Lovalekar MT, House AJ, Smalley BW, Lephart SM. Dietary Habits of Soldiers of 101st Airborne Division Air...W81XWH-06-2-0070 and #W81XWH-09-2-0095 Dietary Habits of Soldiers of 101stAirborne Division Air Assault Kim Crawford, Matthew E. Darnell, John P. Abt...physical and tactical training. PURPOSE: To evaluate dietary habits of 101stAirborne Division (Air Assault) (101st ABN DIV (AA)) Soldiers. METHODS: A

  7. Plasma Biomedicine in Orthopedics

    Hamaguchi, Satsohi


    Various effects of plasmas irradiation on cells, tissues, and biomaterials relevant for orthopedic applications have been examined. For direct application of plasmas to living cells or tissues, dielectric barrier discharges (DBDs) with helium flows into ambient air were used. For biomaterial processing, on the other hand, either helium DBDs mentioned above or low-pressure discharges generated in a chamber were used. In this presentation, plasma effects on cell proliferation and plasma treatment for artificial bones will be discussed. First, the conditions for enhanced cell proliferation in vitro by plasma applications have been examined. The discharge conditions for cell proliferation depend sensitively on cell types. Since cell proliferation can be enhanced even when the cells are cultured in a plasma pre-treated medium, long-life reactive species generated in the medium by plasma application or large molecules (such as proteins) in the medium modified by the plasma are likely to be the cause of cell proliferation. It has been found that there is strong correlation between (organic) hydroperoxide generation and cell proliferation. Second, effects of plasma-treated artificial bones made of porous hydroxyapatite (HA) have been examined in vitro and vivo. It has been found that plasma treatment increases hydrophilicity of the surfaces of microscopic inner pores, which directly or indirectly promotes differentiation of mesenchymal stem cells introduced into the pores and therefore causes faster bone growth. The work has been performed in collaboration with Prof. H. Yoshikawa and his group members at the School of Medicine, Osaka University.

  8. Plasma detachment in linear devices

    Ohno, N.


    Plasma detachment research in linear devices, sometimes called divertor plasma simulators, is reviewed. Pioneering works exploring the concept of plasma detachment were conducted in linear devices. Linear devices have contributed greatly to the basic understanding of plasma detachment such as volume plasma recombination processes, detached plasma structure associated with particle and energy transport, and other related issues including enhancement of convective plasma transport, dynamic response of plasma detachment, plasma flow reversal, and magnetic field effect. The importance of plasma detachment research using linear devices will be highlighted aimed at the design of future DEMO.

  9. Advanced plasma diagnostics for plasma processing

    Malyshev, Mikhail Victorovich


    A new, non-intrusive, non-perturbing diagnostic method was developed that can be broadly applied to low pressure, weakly ionized plasmas and glow discharges-trace rare gases optical emission spectroscopy (TRG-OES). The method is based on a comparison of intensities of atomic emission from trace amounts of inert gases (He, Ne, Ar, Kr, and Xe) that are added to the discharge to intensities calculated from the theoretical model. The model assumes a Maxwellian electron energy distribution function (EEDF), computes the population of emitting levels both from the ground state and the metastable states of rare gases, and from the best fit between theory and experiment determines electron temperature (Te). Subject to conditions, TRG-OES can also yield electron density or its upper or lower limit. From the comparison of the emission from levels excited predominantly by high energy electrons to that excited by low energy electrons, information about the EEDF can be obtained. The use of TRG-OES also allows a traditionally qualitative actinometry technique (determination of concentration of radical species in plasma through optical emission) to become a precise quantitative method by including Te and rare gases metastables effects. A combination of TRG-OES, advanced actinometry, and Langmuir probe measurements was applied to several different plasma reactors and regimes of operation. Te measurements and experiments to correct excitation cross section were conducted in a laboratory helical resonator. Two chamber configuration of a commercial (Lam Research) metal etcher were studied to determine the effects of plasma parameters on plasma-induced damage. Two different methods (RF inductive coupling and ultra-high frequency coupling) for generating a plasma in a prototype reactor were also studied. Pulsed plasmas, a potential candidate to eliminate the plasma-induced damage to microelectronics devices that occurs in manufacturing due to differential charging of the wafer, have

  10. In vivo left ventricular assist induced coagulation derangements. Comparison of Sarns-3M and St. Jude Medical circuits.

    Curtis, J J; Wagner-Mann, C C; Mann, F A; Demmy, T L; Walls, J T; Schmaltz, R A


    An in vitro comparison of centrifugal pumping systems manufactured by Sarns-3M and St. Jude Medical revealed a difference in blood cell derangement. The purpose of this study was to compare in vivo the effects of 96 hr of left ventricular assist (LVA) on indexes of coagulopathy, hemolysis, and complement activation. Two groups of calves (each: n = 5) were instrumented with identical left atrial to thoracic aorta centrifugal pumping circuits using either Sarns-3M or St. Jude centrifugal pumps. Laboratory evaluations were performed pre-assist and at 1, 4, 24, 48, 72, and 96 hr during LVA. Platelet counts dropped significantly by 24 hr (Sarns-3M: 28%; St. Jude: 30%); no significant change in function was noted. Activated clotting time increased slightly (p > 0.05). Prothrombin time increased at 4 and 24 hr of LVA, returning to baseline by 96 hr (p Sarns-3M device never reached significance. No significant changes in lactate dehydrogenase or plasma free hemoglobin were detected. Complement fraction C5a rose by 1 hr of LVA (p Sarns-3M and St. Jude LVA caused coagulation derangement in calves, 2) neither pump demonstrated an advantage regarding coagulation and complement parameters, 3) hemolysis observed with the Sarns-3M pump in vitro was not evidenced in vivo, and 4) in vitro evidenced centrifugal pump differences may not be realized in vivo.

  11. Properties of plasma radiation during discharges with improved confinement on HL-2A Tokamak

    Gao Jin-Ming; Liu Yi; Li Wei; Cui Zheng-Ying; Zhou Yan; Huang Yuan; Ji Xiao-Quan


    In the recent experiment on the HL-2A tokamak,two types of improved confinement regimes have been achieved in different configurations.One is the improved confinement regime in Umiter configuration during electron cyclotron resonant heating(ECRH),characterized by a sharp decrease in Hσ emission accompanied by an increase in the total radiation of plasma,the line averaged electron density and the stored energy of plasma.The other is high confinement regime(H-mode)in divertor configuration during a combination of ECRH and Neutral beam injection(NBI)heating,characterized with edge localized modes(ELMs)besides the features mentioned above.The ELMs are found to be localized on the plasma edge(r/α≥0.8),causing average losses of particles and stored energy in the ranges of about1-3% and 3-5% respectively during a single ELM event.So far,the ELMs observed in the HL-2A are type Ⅲ ELMs with low amplitude and high repetition frequency in a range from 200 Hz to 350 Hz.An investigation of the radiated power density profiles shows that radiative cooling effect plays a significant role in the transition back to the L-mode and the triggering of ELM events.

  12. Pulsed plasma arc cladding

    龙; 白钢; 李振民; 张赋升; 杨思乾


    A prototype of Pulsed Plasma Arc Cladding system was developed, in which single power source supplies both transferred plasma arc (TPA) and non-transferred plasma arc (N-TPA). Both plasmas work in turn in a high frequency controlled by an IGBT connecting nozzle and workpiece. The working frequency of IGBT ranges from 50 ~ 7000Hz, in which the plasmas can work in turn smoothly. Higher than 500 Hz of working frequency is suggested for promotion of cladding quality and protection of IGBT. Drag phenomenon of TPA intensifies as the frequency goes up, which tends to increase the current proportion of TPA and suppress N-TPA. The occupation ratio of IGBT can be regulated from 5% ~ 95%, which balances the power supplies of both plasmas. An occupation ratio higher than 50% gives adequate proportion of arc current for N-TPA to preheat powder.

  13. Introduction to Complex Plasmas

    Bonitz, Michael; Ludwig, Patrick


    Complex plasmas differ from traditional plasmas in many ways: these are low-temperature high pressure systems containing nanometer to micrometer size particles which may be highly charged and strongly interacting. The particles may be chemically reacting or be in contact with solid surfaces, and the electrons may show quantum behaviour. These interesting properties have led to many applications of complex plasmas in technology, medicine and science. Yet complex plasmas are extremely complicated, both experimentally and theoretically, and require a variety of new approaches which go beyond standard plasma physics courses. This book fills this gap presenting an introduction to theory, experiment and computer simulation in this field. Based on tutorial lectures at a very successful recent Summer Institute, the presentation is ideally suited for graduate students, plasma physicists and experienced undergraduates.

  14. Ultracold Neutral Plasmas

    Killian, T C; Gupta, P; Laha, S; Martinez, Y N; Mickelson, P G; Nagel, S B; Saenz, A D; Simien, C E; Killian, Thomas C.


    Ultracold neutral plasmas are formed by photoionizing laser-cooled atoms near the ionization threshold. Through the application of atomic physics techniques and diagnostics, these experiments stretch the boundaries of traditional neutral plasma physics. The electron temperature in these plasmas ranges from 1-1000 K and the ion temperature is around 1 K. The density can approach $10^{11}$ cm$^{-3}$. Fundamental interest stems from the possibility of creating strongly-coupled plasmas, but recombination, collective modes, and thermalization in these systems have also been studied. Optical absorption images of a strontium plasma, using the Sr$^+$ ${^2S_{1/2}} -> {^2P_{1/2}}$ transition at 422 nm, depict the density profile of the plasma, and probe kinetics on a 50 ns time-scale. The Doppler-broadened ion absorption spectrum measures the ion velocity distribution, which gives an accurate measure of the ion dynamics in the first microsecond after photoionization.

  15. What is a plasma?

    Intrator, Thomas P. [Los Alamos National Laboratory


    This introduction will define the plasma fourth state of matter, where we find plasmas on earth and beyond, and why they are useful. There are applications to many consumer items, fusion energy, scientific devices, satellite communications, semiconductor processing, spacecraft propulsion, and more. Since 99% of our observable universe is ionized gas, plasma physics determines many important features of astrophysics, space physics, and magnetosphere physics in our solar system. We describe some plasma characteristics, examples in nature, some useful applications, how to create plasmas. A brief introduction to the theoretical framework includes the connection between kinetic and fluid descriptions, quasi neutrality, Debye shielding, ambipolar electric fields, some plasma waves. Hands-on demonstrations follow. More complete explanations will follow next week.

  16. Pulsed plasma electron sourcesa)

    Krasik, Ya. E.; Yarmolich, D.; Gleizer, J. Z.; Vekselman, V.; Hadas, Y.; Gurovich, V. Tz.; Felsteiner, J.


    There is a continuous interest in research of electron sources which can be used for generation of uniform electron beams produced at E ≤105 V/cm and duration ≤10-5 s. In this review, several types of plasma electron sources will be considered, namely, passive (metal ceramic, velvet and carbon fiber with and without CsI coating, and multicapillary and multislot cathodes) and active (ferroelectric and hollow anodes) plasma sources. The operation of passive sources is governed by the formation of flashover plasma whose parameters depend on the amplitude and rise time of the accelerating electric field. In the case of ferroelectric and hollow-anode plasma sources the plasma parameters are controlled by the driving pulse and discharge current, respectively. Using different time- and space-resolved electrical, optical, spectroscopical, Thomson scattering and x-ray diagnostics, the parameters of the plasma and generated electron beam were characterized.

  17. Space plasma physics research

    Comfort, Richard H.; Horwitz, James L.


    During the course of this grant, work was performed on a variety of topics and there were a number of significant accomplishments. A summary of these accomplishments is included. The topics studied include empirical model data base, data reduction for archiving, semikinetic modeling of low energy plasma in the inner terrestrial magnetosphere and ionosphere, O(+) outflows, equatorial plasma trough, and plasma wave ray-tracing studies. A list of publications and presentations which have resulted from this research is also included.

  18. Atmospheric Plasma Depainting


    Plasma Carbon Dioxide Water Vapor 11 Atmospheric Plasma Depainting, ASETSDefense, Nov 19, 2014 Features and Benefits of APCR Technology Feature...Depainting, ASETSDefense, Nov 19, 2014 14 APC on Aluminum Removal to Primer RAM on Carbon Fiber Partial Topcoat Removal APC Topcoat RAM...60Hz Plasma Flux™ Power Supply VENT To Facility HEPA <= Filtration COTS Six-Axis Robot Aircraft part Particulate Collection System

  19. Plasma nitriding of steels

    Aghajani, Hossein


    This book focuses on the effect of plasma nitriding on the properties of steels. Parameters of different grades of steels are considered, such as structural and constructional steels, stainless steels and tools steels. The reader will find within the text an introduction to nitriding treatment, the basis of plasma and its roll in nitriding. The authors also address the advantages and disadvantages of plasma nitriding in comparison with other nitriding methods. .


    Pencho Kosev


    Full Text Available PURPOSE: To find out the PRP application effects in TKA on pain syndrome, wound healing, postoperative blood loss, range of motion and the knee circumference (centimetry. MATERIAL AND METHOD: The preparation of the platelet-rich plasma is based on our treatment algorithm. 20 patients have been subject to TKA within the period from October 2012 to November 2014 and underwent TKA, as platelet rich plasma was used intraoperatively. The average patient age is 72,3; 9 male and 11 female patients. Control group consisted of 17 patients, who underwent surgery in the same period but no platelet rich plasma was used during surgery. Average patient age 73,1; 8 male and 9 female patients. RESULTS: The following results have been reported for the PRP group of patients: the average amount of blood in the aspiration drainage tube in 24 hours - 285 ml.; postoperative pain on the 1st postoperative day was - 7 p., on the 5th day - 5 p., on the 10th day - 2 p., average circumference (centimetry of the knee between the 1st and the 10th postoperative day decreased on average by 1,5-2 cm., range of motion – reported average degrees per patient on the 1st postoperative day in sagittal plane: 0-10-20 degrees; on the 10th postoperative day: 0-0-55 degrees, surgical wounds of all patients healed primarily without any complications. No PRP group: average amount of blood in the aspiration drainage in 24 hours – 300 pl., postoperative pain on the 1st, 5th , and 10th postoperative day - 8 p., on the 5th day - 6 p., on the 10th day - 3 p., average knee circumference (centimetry between 1 and 10 postoperative day has decreased by 1 cm on average, range of motion - reported average degrees per patient on the 1st postoperative day in sagittal plane 0-5-20 degrees, on the 10th: 0-0-50 degrees, surgical wounds healed primarily without any complications in 10 patients, but in 7 patients we observed superficial wound edge skin necrosis. CONCLUSION: Our results unequivocally