Natural current profiles in tokamaks

International Nuclear Information System (INIS)

Biskamp, D.

1986-01-01

It is proposed that a certain class of equilibrium, which follow from an elementary variational principle, are the natural current profiles in tokamaks, to which actual discharge profiles tend to relax. (orig.)

Current profile evolution during fast wave current drive on the DIII-D tokamak

International Nuclear Information System (INIS)

Petty, C.C.; Forest, C.B.; Baity, F.W.

1995-06-01

The effect of co and counter fast wave current drive (FWCD) on the plasma current profile has been measured for neutral beam heated plasmas with reversed magnetic shear on the DIII-D tokamak. Although the response of the loop voltage profile was consistent with the application of co and counter FWCD, little difference was observed between the current profiles for the opposite directions of FWCD. The evolution of the current profile was successfully modeled using the ONETWO transport code. The simulation showed that the small difference between the current profiles for co and counter FWCD was mainly due to an offsetting change in the o at sign c current proffie. In addition, the time scale for the loop voltage to reach equilibrium (i.e., flatten) was found to be much longer than the FWCD pulse, which limited the ability of the current profile to fully respond to co or counter FWCD

Current deposition profiles in advanced geometries

International Nuclear Information System (INIS)

Wright, J.C.; Phillips, C.K.; Bonoli, P.T.

1997-01-01

In advanced toroidal devices, plasma shaping can have a significant effect on quantities of interest, including the radio frequency (RF) deposited power and current. Most 2D RF modeling codes use a parameterization of current drive efficiencies to calculate fast wave driven currents. This parameterization is derived from a ray-tracing model in a low-beta model equilibrium. There are difficulties in applying it to a spectrum of waves, and it cannot account for multiple resonances and coherency effects between the electrons and the waves. By evaluating a formulation of the quasilinear diffusion coefficient in an arbitrary inhomogenous geometry with the fields from a full wave code, we address the effects of wave spectra, plasma inhomogeneity, and plasma profile on the evaluation of current deposition profiles. Current profiles are calculated directly from the quasilinear diffusion using the adjoint formulation, with the magnetic equilibrium specified consistently in both the adjoint routine and the full wave code. Results are benchmarked by comparing a power deposition calculation from conductivity to one from the quasilinear expression. RF driven current profiles for various devices, including tokamaks with different aspect ratios, will be presented. copyright 1997 American Institute of Physics

Lower-hybrid counter current drive for edge current density modification in DIII-D

International Nuclear Information System (INIS)

Fenstermacher, M.E.; Nevins, W.M.; Porkolab, M.; Bonoli, P.T.; Harvey, R.W.

1994-01-01

Each of the Advanced Tokamak operating modes in DIII-D is thought to have a distinctive current density profile. So far these modes have only been achieved transiently through experiments which ramp the plasma current and shape. Extension of these modes to steady state requires non-inductive current profile control, e.g., with lower hybrid current drive (LHCD). Calculations of LHCD have been done for DIII-D using the ACCOME and CQL3D codes, showing that counter driven current at the plasma edge can cancel some of the undesirable edge bootstrap current and potentially extend the VH-mode. Results will be presented for scenarios using 2.45 GHz LH waves launched from both the midplane and off-axis ports. The sensitivity of the results to injected power, n e and T e , and launched wave spectrum will also be shown

Profiling Changes in Histone Post-translational Modifications by Top-Down Mass Spectrometry

Energy Technology Data Exchange (ETDEWEB)

Zhou, Mowei; Wu, Si; Stenoien, David L.; Zhang, Zhaorui; Connolly, Lanelle; Freitag, Michael; Pasa-Tolic, Ljiljana

2016-11-11

Top-down mass spectrometry is a valuable tool for charactering post-translational modifications on histones for understanding of gene control and expression. In this protocol, we describe a top-down workflow using liquid chromatography coupled to mass spectrometry for fast global profiling of changes in histone proteoforms between a wild-type and a mutant of a fungal species. The proteoforms exhibiting different abundances can be subjected to further targeted studies by other mass spectrometric or biochemical assays. This method can be generally adapted for preliminary screening for changes in histone modifications between samples such as wild-type vs. mutant, and control vs. disease.

Measurements of edge density profile modifications during IBW on TFTR

International Nuclear Information System (INIS)

Hanson, G.R.; Bush, C.E.; Wilgen, J.B.

1997-01-01

Ion Bernstein wave (IBW) antennas are known to have substantial localized effects on the plasma edge. To allow better understanding and measurement of these effects, the TFTR edge reflectometer has been relocated to the new IBW antenna. This move was facilitated by the incorporation of a diagnostic access tube in the IBW antenna identical to the original diagnostic tube in the fast-wave (FW) antenna. This allowed the reflectometer launcher to simply be moved from the old FW antenna to the new IBW antenna. Only a moderate extension of the waveguide transmission line was required to reconnect the reflectometer to the launcher in its new location. Edge density profile modification during IBW experiments has been observed. Results from IBW experiments will be presented and contrasted to the edge density modifications previously observed during FW heating experiments

Profile modification and hot electron temperature from resonant absorption at modest intensity

International Nuclear Information System (INIS)

Albritton, J.R.; Langdon, A.B.

1980-01-01

Resonant absorption is investigated in expanding plasmas. The momentum deposition associated with the ejection of hot electrons toward low density via wavebreaking readily exceeds that of the incident laser radiation and results in significant modification of the density profile at critical. New scaling of hot electron temperature with laser and plasma parameters is presented

Active core profile and transport modification by application of Ion Bernstein Wave power in PBX-M

International Nuclear Information System (INIS)

LeBlanc, B.; Bell, R.

1995-01-01

Application of Ion Bernstein Wave Heating (IBWH) into the Princeton Beta Experiment-Modification (PBX-M) tokamak stabilizes sawtooth oscillations and generates peaked density profiles. A transport barrier, spatially correlated with the IBWH power deposition profile, is observed in the core of IBWH assisted neutral beam injection (NBI) discharges. A precursor to the fully developed barrier is seen in the soft x-ray data during edge localized mode (ELM) activity. Sustained IBWH operation is conducive to a regime where the barrier supports large triangledown n e , triangledown T e , triangledown v phi , and triangledown T i , delimiting the confinement zone. This regime is reminiscent of the H(high)-mode but with a confinement zone moved inwards. The core region has better than H-mode confinement while the peripheral region is L(low)-mode-like. The peaked profile enhanced NBI core deposition and increases nuclear reactivity. An increase in central T i results from χ i reduction (compared to H-mode) and better beam penetration. Bootstrap current fractions of up to 0.32--0.35 locally and 0.28 overall were obtained when an additional NBI burst is applied to this plasma

Flux surface shape and current profile optimization in tokamaks

International Nuclear Information System (INIS)

Dobrott, D.R.; Miller, R.L.

1977-01-01

Axisymmetric tokamak equilibria of noncircular cross section are analyzed numerically to study the effects of flux surface shape and current profile on ideal and resistive interchange stability. Various current profiles are examined for circles, ellipses, dees, and doublets. A numerical code separately analyzes stability in the neighborhood of the magnetic axis and in the remainder of the plasma using the criteria of Mercier and Glasser, Greene, and Johnson. Results are interpreted in terms of flux surface averaged quantities such as magnetic well, shear, and the spatial variation in the magnetic field energy density over the cross section. The maximum stable β is found to vary significantly with shape and current profile. For current profiles varying linearly with poloidal flux, the highest β's found were for doublets. Finally, an algorithm is presented which optimizes the current profile for circles and dees by making the plasma everywhere marginally stable

Effect of Equilibrium Current Profiles on External Kink Modes in Tokamaks

International Nuclear Information System (INIS)

Liu Chao; Liu Yue; Ma Zhaoshuai

2014-01-01

Based on a linearized MHD model, the effect of equilibrium current profiles on external kink modes in tokamaks is studied by MARS code. Three types of equilibrium current profiles are adopted in this work. Firstly, a set of parabolic equilibrium current profiles are chosen. In these profiles the maximum current values in the center of the plasma are fixed, and the currents have different gradient and jump at the plasma boundary. The effects of the current gradient and jump on the growth rate of external kink mode are investigated. It is found that the current jump which causes the q profiles to change plays an important role in the external kink modes in tokamaks. Secondly, a set of step equilibrium current profiles with different jump positions are chosen. The effect of jump position on external kink modes is discussed. Thirdly, a set of parabolic equilibrium current profiles with current bumps are chosen for the case of off-axis heating. The effects of height, width and position of the current bumps on external kink modes are analyzed. The flat equilibrium current profiles are disadvantageous for the MHD stabilities of tokamaks, because of the large current jump at the plasma edge. The peaked equilibrium current profiles and a large and localized current bump near the plasma edge benefit the MHD stabilities of tokamaks

Stage-specific histone modification profiles reveal global transitions in the Xenopus embryonic epigenome.

Directory of Open Access Journals (Sweden)

Tobias D Schneider

Full Text Available Vertebrate embryos are derived from a transitory pool of pluripotent cells. By the process of embryonic induction, these precursor cells are assigned to specific fates and differentiation programs. Histone post-translational modifications are thought to play a key role in the establishment and maintenance of stable gene expression patterns underlying these processes. While on gene level histone modifications are known to change during differentiation, very little is known about the quantitative fluctuations in bulk histone modifications during development. To investigate this issue we analysed histones isolated from four different developmental stages of Xenopus laevis by mass spectrometry. In toto, we quantified 59 modification states on core histones H3 and H4 from blastula to tadpole stages. During this developmental period, we observed in general an increase in the unmodified states, and a shift from histone modifications associated with transcriptional activity to transcriptionally repressive histone marks. We also compared these naturally occurring patterns with the histone modifications of murine ES cells, detecting large differences in the methylation patterns of histone H3 lysines 27 and 36 between pluripotent ES cells and pluripotent cells from Xenopus blastulae. By combining all detected modification transitions we could cluster their patterns according to their embryonic origin, defining specific histone modification profiles (HMPs for each developmental stage. To our knowledge, this data set represents the first compendium of covalent histone modifications and their quantitative flux during normogenesis in a vertebrate model organism. The HMPs indicate a stepwise maturation of the embryonic epigenome, which may be causal to the progressing restriction of cellular potency during development.

Profiling of integral membrane proteins and their post translational modifications using high-resolution mass spectrometry

Science.gov (United States)

Souda, Puneet; Ryan, Christopher M.; Cramer, William A.; Whitelegge, Julian

2011-01-01

Integral membrane proteins pose challenges to traditional proteomics approaches due to unique physicochemical properties including hydrophobic transmembrane domains that limit solubility in aqueous solvents. A well resolved intact protein molecular mass profile defines a protein’s native covalent state including post-translational modifications, and is thus a vital measurement toward full structure determination. Both soluble loop regions and transmembrane regions potentially contain post-translational modifications that must be characterized if the covalent primary structure of a membrane protein is to be defined. This goal has been achieved using electrospray-ionization mass spectrometry (ESI-MS) with low-resolution mass analyzers for intact protein profiling, and high-resolution instruments for top-down experiments, toward complete covalent primary structure information. In top-down, the intact protein profile is supplemented by gas-phase fragmentation of the intact protein, including its transmembrane regions, using collisionally activated and/or electroncapture dissociation (CAD/ECD) to yield sequence-dependent high-resolution MS information. Dedicated liquid chromatography systems with aqueous/organic solvent mixtures were developed allowing us to demonstrate that polytopic integral membrane proteins are amenable to ESI-MS analysis, including top-down measurements. Covalent post-translational modifications are localized regardless of their position in transmembrane domains. Top-down measurements provide a more detail oriented high-resolution description of post-transcriptional and post-translational diversity for enhanced understanding beyond genomic translation. PMID:21982782

A method for measuring the inductive electric field profile and noninductive current profiles on DIII-D

International Nuclear Information System (INIS)

Forest, C.B.; Luce, T.C.; Politzer, P.A.; Lao, L.L.; Kupfer, K.; Wroblewski, D.

1994-07-01

A new technique for determining the parallel electric field profile and noninductive current profile in tokamak plasmas has been developed and applied to two DIII-D tokamak discharges. Central to this technique is the determination of the current density profile, J(ρ), and poloidal flux, ψ(ρ), from equilibrium reconstructions. From time sequences of the reconstructions, the flux surface averaged, parallel electric field can be estimated from appropriate derivatives of the poloidal flux. With a model for the conductivity and measurements of T e and Z eff , the noninductive fraction of the current can be determined. Such a technique gives the possibility of measuring directly the bootstrap current profile and the noninductively driven current from auxiliary heating such as neutral beam injection or fast wave current drive. Furthermore, if the noninductively driven current is small or if the noninductive current profile is assumed to be known, this measurement provides a local test of the conductivity model under various conditions

Fast-ion transport and neutral beam current drive in ASDEX upgrade

DEFF Research Database (Denmark)

Geiger, B.; Weiland, M.; Jacobsen, Asger Schou

2015-01-01

The neutral beam current drive efficiency has been investigated in the ASDEX Upgrade tokamak by replacing on-axis neutral beams with tangential off-axis beams. A clear modification of the radial fast-ion profiles is observed with a fast-ion D-alpha diagnostic that measures centrally peaked profiles...... during on-axis injection and outwards shifted profiles during off-axis injection. Due to this change of the fast-ion population, a clear modification of the plasma current profile is predicted but not observed by a motional Stark effect diagnostic. The fast-ion transport caused by MHD activity has been...

High-current heavy-ion accelerator system and its application to material modification

International Nuclear Information System (INIS)

Kishimoto, Naoki; Takeda, Yoshihiko; Lee, C.G.; Umeda, Naoki; Okubo, Nariaki; Iwamoto, Eiji

2001-01-01

A high-current heavy-ion accelerator system has been developed to realize intense particle fluxes for material modification. The facility of a tandem accelerator attained 1 mA-class ion current both for negative low-energy ions and positive high-energy ions. The negative ion source of the key device is of the plasma-sputter type, equipped with mutli-cusp magnets and Cs supply. The intense negative ions are either directly used for material irradiation at 60 keV or further accelerated up to 6 MeV after charge transformation. Application of negative ions, which alleviates surface charging, enables us to conduct low-energy high-current irradiation on insulating substrates. Since positive ions above the MeV range are irrelevant for Coulomb repulsion, the facility as a whole meets the needs of high-current irradiation onto insulators over a wide energy range. Application of high flux ions provides technological merits not only for efficient implantation but also for essentially different material kinetics, which may become an important tool of material modification. Other advantages of the system are co-irradiation by intense laser and in-situ detection of kinetic processes. For examples of material modifications, we present nanoparticle fabrication in insulators, and synergistic phenomena by co-irradiation due to ions and photons. (author)

Time evolution of the bootstrap current profile in LHD plasmas

International Nuclear Information System (INIS)

Nakamura, Yuji; Kawaoto, K.; Watanabe, K.Y.

2008-10-01

The direction of the bootstrap current is inverted in the outward shifted plasmas of the Large Helical Device (LHD). In order to verify the reliability of the theoretical models of the bootstrap current in helical plasmas, the rotational transform profiles are observed by the Motional Stark Effect measurement in the bootstrap current carrying plasmas of the LHD, and they are compared with the numerical simulations of the toroidal current profile including the bootstrap current. Since the toroidal current profile is not in the steady state in these plasmas, taking care of the inversely induced component of the toroidal current and finite duration of the resistive diffusion of the toroidal current are important in the numerical simulations. Reasonable agreement can be obtained between the rotational transform profiles measured in the experiments and those calculated in the numerical simulations. (author)

Some high-current ion sources for materials modification

International Nuclear Information System (INIS)

Taylor, T.

1989-01-01

Ion sources for materials modification have evolved through three distinct generations. The first generation was adopted from research accelerators. These cold-cathode plasma-discharge devices generate beam currents of less than 100 μA. The hot-cathode plasma-discharge ion sources, originally developed for isotope separation, comprise the second generation. They produce between 100 μA and 10 mA of beam current. The third generation ion sources give beam currents in excess of 10 mA. This technology, transferred from industrial accelerators, has already made SIMOX (Separation by IMplanted OXygen) into a commercially viable semiconductor process and promises to do the same for ion implantation of metals and insulators. The author focuses on the third generation technology that will play a key role in the future of ion implantation. 10 refs.; 5 figs.; 2 tabs

Full-wave simulations of current profiles for fast magnetosonic wave current drive

International Nuclear Information System (INIS)

Dmitrieva, M.V.; Eriksson, L.-G.; Gambier, D.J.

1992-12-01

Numerical simulations of current drive in tokamaks by fast waves (FWCD) have been performed in the range of the ion cyclotron and at lower frequencies via 3-Dimensional numerical code ICTOR. Trapped particles effects were taken into account in the calculation of the fast wave current drive efficiency and the bootstrap current generation. The global efficiency of FWCD if found to be γ∼ 0.1 x 10 20 AW -1 m -2 for the Joint European Torus tokamak (JET) parameters at a central electron temperature of ∼ 10 kev. The efficiency of FWCD for reactor-like plasmas is found to be γ∼0.3 x 10 20 AW -1 m -2 for ∼ 100% of FWCD and γ∼ 1 x 10 20 AW -1 m -2 for FWCD and ∼ 65% of bootstrap in a total current of ∼ 25MA at a 25kev central temperature with a density of ∼10 20 m -3 and major radius R ∼ 8m. Non-inductive current density profiles are studied. Broad FWCD current profiles are obtained for flat reactor temperature and density profiles with bootstrap current concentrated at the plasma edge. The possibility of a steady-state reactor on full wave (FW) with a large fraction of bootstrap current is discussed. It appears to be impractical to rely on such an external current driven (CD) scheme for a reactor as long a γ is less than 2 x 10 20 AW -1 m -2 . (Author)

Experimentally determined profiles of fast wave current drive on DIII-D

International Nuclear Information System (INIS)

Forest, C.B.; Petty, C.C.; Baity, F.W.; Chiu, S.C.; deGrassie, J.S.; Groebner, R.J.; Ikezi, H.; Jaeger, E.F.; Kupfer, K.; Murakami, M.; Pinsker, R.I.; Prater, R.; Rice, B.W.; Wade, M.R.; Whyte, D.G.

1996-01-01

Profiles of non-inductive current driven by fast waves have been determined for reversed-shear DIII-D discharges. Both the current profile and toroidal electric field profile are determined from time sequences of equilibrium reconstructions [C. B. Forest et al., Phys. Rev. Lett. 73, 2224 (1994)]. Using this information, the measured current profile has been separated into inductive and non-inductive portions. By comparing similar discharges with co and counter antenna phasings and similar fast wave power, the portion of the total non-inductive current driven by fast waves was determined. The experimentally determined profiles of FWCD are in general agreement with theoretical predictions. Specifically, 135 kA was driven by 1.4 MW of rf power with a profile peaked inside ρ=2. copyright 1996 American Institute of Physics

Modification of the genetic effect of gamma irradiation by electric current

International Nuclear Information System (INIS)

Grigor'eva, N.N.; Shakhbazov, V.G.

1985-01-01

The authors study the effect of direct current of varying strength and polarity on the genetic damage due to gamma irradiation of Vicia faba seedlings. The modificational effect of direct current observed earlier is confirmed here. The extent and nature of this effect depends on the strength and polarity of the current as well as interval between irradiation and exposure to the electric field. Conditions having no effect on the irradiated seedlings, those protecting the cells from damage and enhancing the irradiation effect, are identified

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

International Nuclear Information System (INIS)

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

2008-01-01

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

Neural network evaluation of tokamak current profiles for real time control

Science.gov (United States)

Wróblewski, Dariusz

1997-02-01

Active feedback control of the current profile, requiring real-time determination of the current profile parameters, is envisioned for tokamaks operating in enhanced confinement regimes. The distribution of toroidal current in a tokamak is now routinely evaluated based on external (magnetic probes, flux loops) and internal (motional Stark effect) measurements of the poloidal magnetic field. However, the analysis involves reconstruction of magnetohydrodynamic equilibrium and is too intensive computationally to be performed in real time. In the present study, a neural network is used to provide a mapping from the magnetic measurements (internal and external) to selected parameters of the safety factor profile. The single-pass, feedforward calculation of output of a trained neural network is very fast, making this approach particularly suitable for real-time applications. The network was trained on a large set of simulated equilibrium data for the DIII-D tokamak. The database encompasses a large variety of current profiles including the hollow current profiles important for reversed central shear operation. The parameters of safety factor profile (a quantity related to the current profile through the magnetic field tilt angle) estimated by the neural network include central safety factor, q0, minimum value of q, qmin, and the location of qmin. Very good performance of the trained neural network both for simulated test data and for experimental datais demonstrated.

Neural network evaluation of tokamak current profiles for real time control

International Nuclear Information System (INIS)

Wroblewski, D.

1997-01-01

Active feedback control of the current profile, requiring real-time determination of the current profile parameters, is envisioned for tokamaks operating in enhanced confinement regimes. The distribution of toroidal current in a tokamak is now routinely evaluated based on external (magnetic probes, flux loops) and internal (motional Stark effect) measurements of the poloidal magnetic field. However, the analysis involves reconstruction of magnetohydrodynamic equilibrium and is too intensive computationally to be performed in real time. In the present study, a neural network is used to provide a mapping from the magnetic measurements (internal and external) to selected parameters of the safety factor profile. The single-pass, feedforward calculation of output of a trained neural network is very fast, making this approach particularly suitable for real-time applications. The network was trained on a large set of simulated equilibrium data for the DIII-D tokamak. The database encompasses a large variety of current profiles including the hollow current profiles important for reversed central shear operation. The parameters of safety factor profile (a quantity related to the current profile through the magnetic field tilt angle) estimated by the neural network include central safety factor, q 0 , minimum value of q, q min , and the location of q min . Very good performance of the trained neural network both for simulated test data and for experimental datais demonstrated. copyright 1997 American Institute of Physics

Current density profile inside q=1 on Tore Supra

International Nuclear Information System (INIS)

Joffrin, E.; Desgranges, C.; Sabot, R.; Dubois, M.A.

1995-01-01

The Tore Supra polarimeter used to measure the poloidal field distribution is described. The current density profiles are computed in two different ways using the interferometric and polarimetric data in conjunction with the magnetic data and the location of the inversion radius determined by the soft X-ray camera. The current density inside the q=1 surface is investigated for normal and monster sawteeth. Its variation are also measured by the polarimeter and compared with that predicted by the current diffusion equation assuming complete reconnection. Finally, the safety factor profile is compared with that obtained with the striation data of the pellet ablation. The results of the evolution of the q profile during sawteeth are in good agreement with those obtained in other devices. (author) 9 refs.; 4 figs

Proteomic investigation of protein profile changes and amino acid residue-level modification in cooked lamb longissimus thoracis et lumborum: The effect of roasting.

Science.gov (United States)

Yu, Tzer-Yang; Morton, James D; Clerens, Stefan; Dyer, Jolon M

2016-09-01

Protein modifications of meat cooked by typical dry-heat methods (e.g., roasting) are currently not well understood. The present study utilised a shotgun proteomic approach to examine the molecular-level effect of roasting on thin lamb longissimus thoracis et lumborum patties, in terms of changes to both the protein profile and amino acid residue side-chain modifications. Cooking caused aggregation of actin, myosin heavy chains and sarcoplasmic proteins. Longer roasting time resulted in significantly reduced protein extractability as well as protein truncation involving particularly a number of myofibrillar and sarcoplasmic proteins, e.g., 6-phosphofructokinase, beta-enolase, l-lactate dehydrogenase A chain, alpha-actinin-3, actin and possibly myosin heavy chains. Modifications that have potential influence on nutritional properties, including carboxyethyllysine and a potentially glucose-derived N-terminal Amadori compound, were observed in actin and myoglobin after roasting. This study provided new insights into molecular changes resulting from the dry-heat treatment of meat, such as commonly used in food preparation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Determining the near-surface current profile from measurements of the wave dispersion relation

Science.gov (United States)

Smeltzer, Benjamin; Maxwell, Peter; Aesøy, Eirik; Ellingsen, Simen

2017-11-01

The current-induced Doppler shifts of waves can yield information about the background mean flow, providing an attractive method of inferring the current profile in the upper layer of the ocean. We present measurements of waves propagating on shear currents in a laboratory water channel, as well as theoretical investigations of inversion techniques for determining the vertical current structure. Spatial and temporal measurements of the free surface profile obtained using a synthetic Schlieren method are analyzed to determine the wave dispersion relation and Doppler shifts as a function of wavelength. The vertical current profile can then be inferred from the Doppler shifts using an inversion algorithm. Most existing algorithms rely on a priori assumptions of the shape of the current profile, and developing a method that uses less stringent assumptions is a focus of this study, allowing for measurement of more general current profiles. The accuracy of current inversion algorithms are evaluated by comparison to measurements of the mean flow profile from particle image velocimetry (PIV), and a discussion of the sensitivity to errors in the Doppler shifts is presented.

Enhancement of anodic biofilm formation and current output in microbial fuel cells by composite modification of stainless steel electrodes

Science.gov (United States)

Liang, Yuxiang; Feng, Huajun; Shen, Dongsheng; Li, Na; Guo, Kun; Zhou, Yuyang; Xu, Jing; Chen, Wei; Jia, Yufeng; Huang, Bin

2017-02-01

In this paper, we first systematically investigate the current output performance of stainless steel electrodes (SS) modified by carbon coating (CC), polyaniline coating (PANI), neutral red grafting (NR), surface hydrophilization (SDBS), and heat treatment (HEAT). The maximum current density of 13.0 A m-2 is obtained on CC electrode (3.0 A m-2 of the untreated anode). Such high performance should be attributed to its large effective surface area, which is 2.3 times that of the unmodified electrode. Compared with SS electrode, about 3-fold increase in current output is achieved with PANI. Functionalization with hydrophilic group and electron medium result in the current output rising to 1.5-2 fold, through enhancing bioadhesive and electron transport rate, respectively. CC modification is the best choice of single modification for SS electrode in this study. However, this modification is not perfect because of its poor hydrophilicity. So CC electrode is modified by SDBS for further enhancing the current output to 16 A m-2. These results could provide guidance for the choice of suitable single modification on SS electrodes and a new method for the perfection of electrode performance through composite modification.

Neural network evaluation of tokamak current profiles for real time control (abstract)

Science.gov (United States)

Wróblewski, Dariusz

1997-01-01

Active feedback control of the current profile, requiring real-time determination of the current profile parameters, is envisioned for tokamaks operating in enhanced confinement regimes. The distribution of toroidal current in a tokamak is now routinely evaluated based on external (magnetic probes, flux loops) and internal (motional Stark effect) measurements of the poloidal magnetic field. However, the analysis involves reconstruction of magnetohydrodynamic equilibrium and is too intensive computationally to be performed in real time. In the present study, a neural network is used to provide a mapping from the magnetic measurements (internal and external) to selected parameters of the safety factor profile. The single-pass, feedforward calculation of output of a trained neural network is very fast, making this approach particularly suitable for real-time applications. The network was trained on a large set of simulated equilibrium data for the DIII-D tokamak. The database encompasses a large variety of current profiles including the hollow current profiles important for reversed central shear operation. The parameters of safety factor profile (a quantity related to the current profile through the magnetic field tilt angle) estimated by the neural network include central safety factor, q0, minimum value of q, qmin, and the location of qmin. Very good performance of the trained neural network both for simulated test data and for experimental data is demonstrated.

Neural network evaluation of tokamak current profiles for real time control (abstract)

International Nuclear Information System (INIS)

Wroblewski, D.

1997-01-01

Active feedback control of the current profile, requiring real-time determination of the current profile parameters, is envisioned for tokamaks operating in enhanced confinement regimes. The distribution of toroidal current in a tokamak is now routinely evaluated based on external (magnetic probes, flux loops) and internal (motional Stark effect) measurements of the poloidal magnetic field. However, the analysis involves reconstruction of magnetohydrodynamic equilibrium and is too intensive computationally to be performed in real time. In the present study, a neural network is used to provide a mapping from the magnetic measurements (internal and external) to selected parameters of the safety factor profile. The single-pass, feedforward calculation of output of a trained neural network is very fast, making this approach particularly suitable for real-time applications. The network was trained on a large set of simulated equilibrium data for the DIII-D tokamak. The database encompasses a large variety of current profiles including the hollow current profiles important for reversed central shear operation. The parameters of safety factor profile (a quantity related to the current profile through the magnetic field tilt angle) estimated by the neural network include central safety factor, q 0 , minimum value of q, q min , and the location of q min . Very good performance of the trained neural network both for simulated test data and for experimental data is demonstrated. copyright 1997 American Institute of Physics

Lower hybrid wave accessibility as a means for current profile control

International Nuclear Information System (INIS)

Briffod, G.; Gormezano, C.; Parlange, F.; Van Houtte, D.

1986-01-01

Powerful ICRH experiments on JET and Neutral Beam Injection of various species on TFTR have recently confirmed the insensitivity of the temperature and safety factor profile shapes to the heating profile and the important role played by the sawtooth activity on the overall performances. In order to overcome these limitations, we propose in this paper, in a Tokamak operating at constant plasma current: to control the resistive part of the current by driving an H.F. current by Lower Hybrid Wave. To act on the current profile, with the constraint that q(o) > 1 by controlling the wave penetration. Constant plasma current Tokamak discharges in which a part of the current is driven by L.H.W. have been extensively studied on PETULA and this mode of operation has proven to be very efficient in stabilizing the sawtooth and M.H.D. activity

Observation of Self-Generated Flows in Tokamak Plasmas with Lower-Hybrid-Driven Current

International Nuclear Information System (INIS)

Ince-Cushman, A.; Rice, J. E.; Reinke, M.; Greenwald, M.; Wallace, G.; Parker, R.; Fiore, C.; Hughes, J. W.; Bonoli, P.; Shiraiwa, S.; Hubbard, A.; Wolfe, S.; Hutchinson, I. H.; Marmar, E.; Bitter, M.; Wilson, J.; Hill, K.

2009-01-01

In Alcator C-Mod discharges lower hybrid waves have been shown to induce a countercurrent change in toroidal rotation of up to 60 km/s in the central region of the plasma (r/a∼<0.4). This modification of the toroidal rotation profile develops on a time scale comparable to the current redistribution time (∼100 ms) but longer than the energy and momentum confinement times (∼20 ms). A comparison of the co- and countercurrent injected waves indicates that current drive (as opposed to heating) is responsible for the rotation profile modifications. Furthermore, the changes in central rotation velocity induced by lower hybrid current drive (LHCD) are well correlated with changes in normalized internal inductance. The application of LHCD has been shown to generate sheared rotation profiles and a negative increment in the radial electric field profile consistent with a fast electron pinch

Exploration of one-dimensional plasma current density profile for K-DEMO steady-state operation

Energy Technology Data Exchange (ETDEWEB)

Kang, J.S. [Seoul National University, Seoul 151-742 (Korea, Republic of); Jung, L. [National Fusion Research Institute, Daejeon (Korea, Republic of); Byun, C.-S.; Na, D.H.; Na, Y.-S. [Seoul National University, Seoul 151-742 (Korea, Republic of); Hwang, Y.S., E-mail: yhwang@snu.ac.kr [Seoul National University, Seoul 151-742 (Korea, Republic of)

2016-11-01

Highlights: • One-dimensional current density and its optimization for the K-DEMO are explored. • Plasma current density profile is calculated with an integrated simulation code. • The impact of self and external heating profiles is considered self-consistently. • Current density is identified as a reference profile by minimizing heating power. - Abstract: Concept study for Korean demonstration fusion reactor (K-DEMO) is in progress, and basic design parameters are proposed by targeting high magnetic field operation with ITER-sized machine. High magnetic field operation is a favorable approach to enlarge relative plasma performance without increasing normalized beta or plasma current. Exploration of one-dimensional current density profile and its optimization process for the K-DEMO steady-state operation are reported in this paper. Numerical analysis is conducted with an integrated plasma simulation code package incorporating a transport code with equilibrium and current drive modules. Operation regimes are addressed with zero-dimensional system analysis. One-dimensional plasma current density profile is calculated based on equilibrium, bootstrap current analysis, and thermal transport analysis. The impact of self and external heating profiles on those parameters is considered self-consistently, where thermal power balance and 100% non-inductive current drive are the main constraints during the whole exploration procedure. Current and pressure profiles are identified as a reference steady-state profile by minimizing the external heating power with desired fusion power.

Observation of instability-induced current redistribution in a spherical-torus plasma.

Science.gov (United States)

Menard, J E; Bell, R E; Gates, D A; Kaye, S M; LeBlanc, B P; Levinton, F M; Medley, S S; Sabbagh, S A; Stutman, D; Tritz, K; Yuh, H

2006-09-01

A motional Stark effect diagnostic has been utilized to reconstruct the parallel current density profile in a spherical-torus plasma for the first time. The measured current profile compares favorably with neoclassical theory when no large-scale magnetohydrodynamic instabilities are present in the plasma. However, a current profile anomaly is observed during saturated interchange-type instability activity. This apparent anomaly can be explained by redistribution of neutral beam injection current drive and represents the first observation of interchange-type instabilities causing such redistribution. The associated current profile modifications contribute to sustaining the central safety factor above unity for over five resistive diffusion times, and similar processes may contribute to improved operational scenarios proposed for ITER.

Electron cyclotron heating for current profile control of non-circular plasmas

International Nuclear Information System (INIS)

Chan, V.S.; Davidson, R.; Guest, G.; Hacker, M.; Miller, L.

1981-01-01

Electron Cyclotron Heating (ECH) offers a promising approach to modifying the radial profiles of electron temperature and plasma current in tokamaks to increase the ideal MHD beta limits and permit experimental access to particular noncircular cross-section tokamaks that cannot be achieved with the peaked current profiles characteristic of ohmically heated tokamaks. We use a one-and-one-half-dimensional, time-dependent transport model that incorporates a self-consistent model of electron cyclotron power absorption to study the temporal evolution of electron temperature and plasma current profiles and the resulting noncircular equilibria. Startup scenarios for high-beta dees and doublets are investigated with this transport modeling

Fast electron current density profile and diffusion studies during LHCD in PBX-M

International Nuclear Information System (INIS)

Jones, S.E.; Kesner, J.; Luckhardt, S.; Paoletti, F.

1993-08-01

Successful current profile control experiments using lower hybrid current drive (LCHD) clearly require knowledge of (1) the location of the driven fast electrons and (2) the ability to maintain that location from spreading due to radial diffusion. These issues can be addressed by examining the data from the hard x-ray camera on PBX-M, a unique diagnostic producing two-dimensional, time resolved tangential images of fast electron bremsstrahlung. Using modeling, these line-of-sight images are inverted to extract a radial fast electron current density profile. We note that ''hollow'' profiles have been observed, indicative of off-axis current drive. These profiles can then be used to calculate an upper bound for an effective fast electron diffusion constant: assuming an extremely radially narrow lower hybrid absorption profile and a transport model based on Rax and Moreau, a model fast electron current density profile is calculated and compared to the experimentally derived profile. The model diffusion constant is adjusted until a good match is found. Applied to steady-state quiescent modes on PBX-M, we obtain an upper limit for an effective diffusion constant of about D*=1.1 m 2 /sec

Control of the current density profile with lower hybrid current drive on PBX-M

International Nuclear Information System (INIS)

Bell, R.E.; Bernabei, S.; Chu, T.K.; Gettelfinger, G.; Greenough, N.; Hatcher, R.; Ignat, D.; Jardin, S.; Kaita, R.; Kaye, S.; Kozub, T.; Kugel, H.; LeBlanc, B.; Okabayashi, M.; Paul, S.; Sauthoff, N.; Sesnic, S.; Sun, Y.; Takahashi, H.; Tighe, W.; Valeo, E.; von Goeler, S.; Jones, S.; Kesner, J.; Luckhardt, S.; Paoletti, F.; Levinton, F.; Timini, F.

1993-07-01

Lower hybrid current drive (LHCD) is being explored as a means to control the current density profile on PBX-M with the goal of raising the central safety factor q(O) to values of 1.5-2 to facilitate access to a full-volume second stable regime. Initial experiments have been conducted with up to 400 kW of 4.6 GHz LH power in circular and indented plasmas with modest parameters. A tangential-viewing two-dimensional hard x-ray imaging diagnostic has been used to observe the bremsstrahlung emission from the suprathermal electrons generated during LHCD. Hollow hard x-ray images have indicated off-axis localization of the driven current. A serious obstacle to the control of the current density profile with LHCD is the concomitant generation of MHD activity, which can seriously degrade the confinement of suprathermal electrons. By combining neutral beam injection with LHCD, an MHD-free condition has been obtained where q(O) is raised above 1

Energy deposition profile for modification proposal of ISOLDE’s HRS Beam Dump, from FLUKA simulations

CERN Document Server

Vlachoudis, V

2014-01-01

The current ISOLDE HRS beam dump has been found to be unsuitable on previous simulations, due to thermomechanical stresses. In this paper a proposal for modifying HRS dump is studied using FLUKA. The energy deposited in this modified beam dump and the amount of neutrons streaming to the tunnel area are scored and compared with the simulation of current dump. Two versions of the modification have been assessed, determining which of them is more desirable in terms of influence of radiation on ISOLDE’s tunnel. Finally, a rough estimate of temperature raise in the modified dump is shown. Further conclusions on the adequacy of these modifications need to include the thermomechanical calculations’ results, based on those presented here.

Profile formation and sustainment of autonomous tokamak plasma with current hole configuration

International Nuclear Information System (INIS)

Hayashi, N.; Takizuka, T.; Ozeki, T.

2005-01-01

We have investigated the profile formation and sustainment of tokamak plasmas with the current hole (CH) configuration by using 1.5D time-dependent transport simulations. A model of the current limit inside the CH on the basis of the Axisymmetric Tri-Magnetic-Islands equilibrium is introduced into the transport simulation. We found that a transport model with the sharp reduction of anomalous transport in the reversed-shear (RS) region can reproduce the time evolution of profiles observed in JT-60U experiments. The transport becomes neoclassical-level in the RS region, which results in the formation of profiles with internal transport barrier (ITB) and CH. The CH plasma has an autonomous property because of the strong interaction between a pressure profile and a current profile through the large bootstrap current fraction. The ITB width determined by the neoclassical-level transport agrees well with that measured in JT-60U. The energy confinement inside the ITB agrees with the scaling based on the JT-60U data. The scaling means the autonomous limitation of energy confinement in the CH plasma. The plasma with the large CH is sustained with the full current drive by the bootstrap current. The plasma with the small CH and the small bootstrap current fraction shrinks due to the penetration of inductive current. This shrink is prevented and the CH size can be controlled by the appropriate external current drive (CD). The CH plasma is found to respond autonomically to the external CD. (author)

Modification of K-line emission profiles in laser-created solid-density plasmas

International Nuclear Information System (INIS)

Sengebusch, A.; Reinholz, H.; Roepke, G.

2010-01-01

Complete text of publication follows. X-ray emissions in the keV energy range have shown to be suitable radiation to investigate the properties of laser-created solid-density plasmas. We use the modifications of inner shell transitions due to the environment to characterize these plasmas. A theoretical treatment of spectral line profiles based on a self-consistent ion sphere model is applied on moderately ionized mid-Z materials, such as titanium, silicon and chlorine. We observe large contributions of satellite transitions due to M-shell ionization and excitation. To determine the composition a mixture of various excited and ionized ionic states embedded in a plasma has to be considered. Plasma polarization effects that cause shifts of the emission and ionization energies are taken into account. K-line profiles are calculated for bulk temperatures up to 100 eV and free electron densities up to 10 24 cm -3 in order to analyze recent measurements with respect to the plasma parameters of electron heated target regions. Moreover, in high-intensity laser-matter interactions, inevitable prepulses are likely to create preplasma and shocks within the target before the main pulse arrives. We investigate the influence of density gradients due to prepulses on the spectral profiles. Further, radial bulk temperature distributions as well the composition of the created warm dense matter are inferred.

Modification of steel 35 HL surge current during crystallization

Directory of Open Access Journals (Sweden)

Zhbanova O.M.

2017-04-01

Full Text Available The method of electro steel melt modification 35 HL variable polarity current pulses with a duration of more 10-3s frequency within the 5–33 Hz, 5–24 porosity meanders, strength 30–40 A at a voltage of 180–240 V during crystallization, which allows to obtain high-quality castings 35 HL steel grade. Show that electro melt processing improves the structure and reduces the physical heterogeneity of castings and increases the rate of dissolution of metallic impurities and other components in the melt, providing fine-grained structure and increases the homogeneity of metal carbides reduces the amount of manganese reduces gases and nonmetallic inclusions. Modifying steel 35 HL pulse current during crystallization of the melt increases the physical and mechanical properties of tempered steel, increasing yield strength by 30 %, the tensile strength at 7 % elongation of 1,5 % relative narrowing by 2 %, toughness at 20 %.

Current profile reconstruction using electron temperature imaging diagnostics

International Nuclear Information System (INIS)

Tritz, K.; Stutman, D.; Delgado-Aparicio, L.F.; Finkenthal, M.; Pacella, D.; Kaita, R.; Stratton, B.; Sabbagh, S.

2004-01-01

Flux surface shape information can be used to constrain the current profile for reconstruction of the plasma equilibrium. One method of inferring flux surface shape relies on plasma x-ray emission; however, deviations from the flux surfaces due to impurity and density asymmetries complicate the interpretation. Electron isotherm surfaces should correspond well to the plasma flux surfaces, and equilibrium constraint modeling using this isotherm information constrains the current profile. The KFIT code is used to assess the profile uncertainty and to optimize the number, location and SNR required for the Te detectors. As Te imaging detectors we consider tangentially viewing, vertically spaced, linear gas electron multiplier arrays operated in pulse height analysis (PHA) mode and multifoil soft x-ray arrays. Isoflux coordinate sets provided by T e measurements offer a strong constraint on the equilibrium reconstruction in both a stacked horizontal array configuration and a crossed horizontal and vertical beam system, with q 0 determined to within ±4%. The required SNR can be provided with either PHA or multicolor diagnostic techniques, though the multicolor system requires ∼x4 better statistics for comparable final errors

Analysis of tidal currents in the North Sea from shipboard acoustic Doppler current profiler data

Science.gov (United States)

Vindenes, Håvard; Orvik, Kjell Arild; Søiland, Henrik; Wehde, Henning

2018-06-01

North Sea tidal currents are determined by applying harmonic analysis to ship-borne acoustic Doppler current profiler data recorded from 1999 to 2016, covering large areas of the northern North Sea. Direct current measurement data sets of this magnitude are rare in the otherwise well investigated North Sea, and thus it is a valuable asset in studying and expanding our understanding of its tidal currents and circulation in general. The harmonic analysis is applied to a least squares fit of the current observations at a set of knot points. Results from the harmonic analysis compare favorably to tidal parameters estimated from observations from moored instruments. The analysis shows that the tides are characterized by strong semi-diurnal component, with amplitudes of the principal Lunar constituent ranging from 1.6 cm/s in the Skagerrak to 67 cm/s in the Fair Isle Channel. Diurnal tides are found to be approximately one fifth the strength of the predominant semi-diurnal constituent. Output from a regional barotropic tide model compares well to tidal current determined from the harmonic analysis of the Acoustic Doppler Current Profiler data.

Effect of resistivity profile on current decay time of initial phase of current quench in neon-gas-puff inducing disruptions of JT-60U

Energy Technology Data Exchange (ETDEWEB)

Kawakami, S.; Ohno, N. [Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan); Shibata, Y.; Isayama, A.; Kawano, Y. [Japan Atomic Energy Agency, Naka 311-0193 (Japan); Watanabe, K. Y. [Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan); National Institute for Fusion Science, Toki 509-5292 (Japan); Takizuka, T. [Graduate School of Engineering, Osaka University, Suita 565-0871 (Japan); Okamoto, M. [Ishikawa National College of Technology, Ishikawa 929-0392 (Japan)

2013-11-15

According to an early work [Y. Shibata et al., Nucl. Fusion 50, 025015 (2010)] on the behavior of the plasma current decay in the JT-60U disruptive discharges caused by the radiative collapse with a massive neon-gas-puff, the increase of the internal inductance mainly determined the current decay time of plasma current during the initial phase of current quench. To investigate what determines the increase of the internal inductance, we focus attention on the relationship between the electron temperature (or the resistivity) profile and the time evolution of the current density profile and carry out numerical calculations. As a result, we find the reason of the increase of the internal inductance: The current density profile at the start of the current quench is broader than an expected current density profile in the steady state, which is determined by the temperature (or resistivity) profile. The current density profile evolves into peaked one and the internal inductance is increasing.

Real-time control of current and pressure profiles in tokamak plasmas

International Nuclear Information System (INIS)

Laborde, L.

2005-12-01

Recent progress in the field of 'advanced tokamak scenarios' prefigure the operation regime of a future thermonuclear fusion power plant. Compared to the reference regime, these scenarios offer a longer plasma confinement time thanks to increased magnetohydrodynamic stability and to a better particle and energy confinement through a reduction of plasma turbulence. This should give access to comparable fusion performances at reduced plasma current and could lead to a steady state fusion reactor since the plasma current could be entirely generated non-inductively. Access to this kind of regime is provided by the existence of an internal transport barrier, linked to the current profile evolution in the plasma, which leads to steep temperature and pressure profiles. The comparison between heat transport simulations and experiments allowed the nature of the barriers to be better understood as a region of strongly reduced turbulence. Thus, the control of this barrier in a stationary manner would be a remarkable progress, in particular in view of the experimental reactor ITER. The Tore Supra and JET tokamaks, based in France and in the United Kingdom, constitute ideal instruments for such experiments: the first one allows stationary plasmas to be maintained during several minutes whereas the second one provides unique fusion performances. In Tore Supra, real-time control experiments have been accomplished where the current profile width and the pressure profile gradient were controlled in a stationary manner using heating and current drive systems as actuators. In the JET tokamak, the determination of an empirical static model of the plasma allowed the current and pressure profiles to be simultaneously controlled and so an internal transport barrier to be sustained. Finally, the identification of a dynamic model of the plasma led to the definition of a new controller capable, in principle, of a more efficient control. (author)

Real-time control of the current density and pressure profiles in Jet

International Nuclear Information System (INIS)

Mazon, D.; Moreau, D.; Litaudon, X.; Joffrin, E.; Laborde, L.; Zabeo, L.; Crisanti, F.; Riva, M.; Felton, R.; Murari, A.; Tala, T.

2003-01-01

In order to ultimately control internal transport barriers during advanced operation scenarios, new algorithms using a truncated singular value decomposition of a linearized model operator have been implemented in the JET real-time controller, with the potentiality of retaining the distributed nature of plasma parameter profiles. First experiments using the simplest, lumped-parameter, version of this technique have been dedicated to the feedback control of the current density profile in a negative shear plasma using three heating and current drive actuators, namely neutral beam injection (NBI), ion cyclotron resonant frequency heating (ICRH) and lower hybrid current drive (LHCD). Successful control of the safety factor profile has been achieved on the time scale of the current redistribution time, first during an extended preheat phase with only LHCD as actuator and, then, in quasi steady-state conditions during the main heating phase of a discharge, using the three heating and current drive actuators

Accuracy Improvement of Discharge Measurement with Modification of Distance Made Good Heading

Directory of Open Access Journals (Sweden)

Jongkook Lee

2016-01-01

Full Text Available Remote control boats equipped with an Acoustic Doppler Current Profiler (ADCP are widely accepted and have been welcomed by many hydrologists for water discharge, velocity profile, and bathymetry measurements. The advantages of this technique include high productivity, fast measurements, operator safety, and high accuracy. However, there are concerns about controlling and operating a remote boat to achieve measurement goals, especially during extreme events such as floods. When performing river discharge measurements, the main error source stems from the boat path. Due to the rapid flow in a flood condition, the boat path is not regular and this can cause errors in discharge measurements. Therefore, improvement of discharge measurements requires modification of boat path. As a result, the measurement errors in flood flow conditions are 12.3–21.8% before the modification of boat path, but 1.2–3.7% after the DMG modification of boat path. And it is considered that the modified discharges are very close to the observed discharge in the flood flow conditions. In this study, through the distance made good (DMG modification of the boat path, a comprehensive discharge measurement with high accuracy can be achieved.

Gene expression profiling during intensive cardiovascular lifestyle modification: Relationships with vascular function and weight loss

Directory of Open Access Journals (Sweden)

Heather L. Blackburn

2015-06-01

Full Text Available Heart disease and related sequelae are a leading cause of death and healthcare expenditure throughout the world. Although many patients opt for surgical interventions, lifestyle modification programs focusing on nutrition and exercise have shown substantial health benefits and are becoming increasing popular. We conducted a year-long lifestyle modification program to mediate cardiovascular risk through traditional risk factors and to investigate how molecular changes, if present, may contribute to long-term risk reduction. Here we describe the lifestyle intervention, including clinical and molecular data collected, and provide details of the experimental methods and quality control parameters for the gene expression data generated from participants and non-intervention controls. Our findings suggest successful and sustained modulation of gene expression through healthy lifestyle changes may have beneficial effects on vascular health that cannot be discerned from traditional risk factor profiles. The data are deposited in the Gene Expression Omnibus, series GSE46097 and GSE66175.

Magnetohydrodynamic effects of current profile control in reversed field pinches

International Nuclear Information System (INIS)

Sovinec, C.R.; Prager, S.C.

1999-01-01

Linear and non-linear MHD computations are used to investigate reversed field pinch configurations with magnetic fluctuations reduced through current profile control. Simulations with reduced ohmic drive and moderate auxiliary current drive, represented generically with an electron force term, applied locally in radius near the plasma edge show magnetic fluctuation energies that are orders of magnitude smaller than those in simulations without profile control. The core of the improved configurations has reduced magnetic shear and closed flux surfaces in some cases, and reversal is sustained through the auxiliary current drive. Modes resonant near the edge may become unstable with auxiliary drive, but their saturation levels can be controlled. The space of auxiliary drive parameters is explored, and the ill effects of deviating far from optimal conditions is demonstrated in non-linear simulations. (author)

Diagnostic development for current density profile control at KSTAR

Energy Technology Data Exchange (ETDEWEB)

Ko, J., E-mail: jinseok@nfri.re.kr [National Fusion Research Institute, Daejeon 34133 (Korea, Republic of); University of Science and Technology, Daejeon 34113 (Korea, Republic of); Chung, J. [National Fusion Research Institute, Daejeon 34133 (Korea, Republic of); Messmer, M.C.C. [Department of Applied Physics, Eindhoven University of Technology, Eindhoven (Netherlands)

2016-11-01

Highlights: • The motional Stark effect (MSE) diagnostic installed at KSTAR. • Engineering challenges and solutions on the design and fabrication of the front optics housing and filter modules. • Characterization of the bandpass filters and the responses to polarized light. - Abstract: The current density profile diagnostics are critical for the control of the steady-state burning plasma operations. A multi-channel motional Stark effect (MSE) diagnostic system has been implemented for the measurements of the internal magnetic field structures that constrain the magnetic equilibrium reconstruction to accurately produce the tokamak safety factor and current density profiles for the Korea Superconducting Tokamak Advanced Research (KSTAR). This work presents the design and fabrication of the front optics and the filter modules and the calibration activities for the MSE diagnostic at KSTAR.

Optimization and control of the plasma shape and current profile in noncircular cross-section tokamaks

International Nuclear Information System (INIS)

Moore, R.W.; Bernard, L.C.; Chan, V.S.; Davidson, R.H.; Dobrott, D.R.; Helton, F.J.; Miller, R.L.; Pfeiffer, W.; Waltz, R.E.; Wang, T.S.

1980-06-01

High-β equilibria which are stable to all ideal MHD modes are found by optimizing the plasma shape and current profile for doublets, up-down asymmetric dees, and symmetric dees. The ideal MHD stability of these equilibria for low toroidal mode number n is analyzed with a global MHD stability code, GATO. The stability to high-n modes is analyzed with a localized ballooning code, BLOON. The attainment of high β is facilitated by an automated optimization search on shape and current parameters. The equilibria are calculated with a free-boundary equilibrium code using coils appropriate for the Doublet III experimental device. The optimal equilibria are characterized by broad current profiles with values of β/sub poloidal/ approx. =1. Experimental realization of the shapes and current profiles giving the highest β limits is explored with a 1 1/2-D transport code, which simulates the time evolution of the 2-D MHD equilibrium while calculating consistent current profiles from a 1-D transport model. Transport simulations indicate that nearly optimal shapes may be obtained provided that the currents in the field-shaping coils are appropriately programmed and the plasma current profile is sufficiently broad. Obtaining broad current profiles is possible by current ramping, neutral beam heating, and electron cyclotron heating. With combinations of these techniques it is possible to approach the optimum β predicted by the MHD theory

Modifications in agricultural and animal breeding current operations to reduce the contamination of food chains

International Nuclear Information System (INIS)

Maubert, Henry; Renard, Philippe

1997-01-01

After a nuclear accident it is compulsory to reduce as much as possible the population exposure to radioactive aerosols deposed upon soils and different surfaces. The radio-agronomic countermeasures are protection directives applicable to the agricultural system and agro-alimentary chain which enable to implement this commandment. Their intrinsic and cumulated efficiency, the conditions and preoccupations of implementation are now better recognized especially now by their large scale application after the Chernobyl accident. As modifications in the current agricultural operation two procedures are mentioned: the rehabilitation techniques and the utilization of adjuvants. Concerning modifications in the current animal breeding methodology in the specific conditions of animal production and restricted pasturage there are discussed methods of diminishing the metabolic transfer to milk and meat and removing radioactivity by proper and simpler agro-alimentary processing and culinary preparations

Towards Current Profile Control in ITER: Potential Approaches and Research Needs

Science.gov (United States)

Schuster, E.; Barton, J. E.; Wehner, W. P.

2014-10-01

Many challenging plasma control problems still need to be addressed in order for the ITER Plasma Control System (PCS) to be able to successfully achieve the ITER project goals. For instance, setting up a suitable toroidal current density profile is key for one possible advanced scenario characterized by noninductive sustainment of the plasma current and steady-state operation. The nonlinearity and high dimensionality exhibited by the plasma demand a model-based current-profile control synthesis procedure that can accommodate this complexity through embedding the known physics within the design. The development of a model capturing the dynamics of the plasma relevant for control design enables not only the design of feedback controllers for regulation or tracking but also the design of optimal feedforward controllers for a systematic model-based approach to scenario planning, the design of state estimators for a reliable real-time reconstruction of the plasma internal profiles based on limited and noisy diagnostics, and the development of a fast predictive simulation code for closed-loop performance evaluation before implementation. Progress towards control-oriented modeling of the current profile evolution and associated control design has been reported following both data-driven and first-principles-driven approaches. An overview of these two approaches will be provided, as well as a discussion on research needs associated with each one of the model applications described above. Supported by the US Department of Energy under DE-SC0001334 and DE-SC0010661.

Optimization and control of plasma shape and current profile in non-circular cross-section tokamaks

International Nuclear Information System (INIS)

Moore, R.W.; Bernard, L.C.; Chan, V.S.

1981-01-01

Tokamaks with elongated, non-circular cross-sections are under consideration as fusion reactors because they have the potential for stable operation at high β. Ideal MHD theory, however, predicts that careful current profile control will be required to achieve the potential high-β advantages of non-circular cross-sections. In this paper, high-β equilibria which are stable to all ideal MHD modes are found by optimizing the plasma shape and current profile for doublets, up-down asymmetric dees, and symmetric dees. The ideal MHD stability of these equilibria for low toroidal mode number n is analysed with a global MHD stability code, GATO. The stability to high-n modes is analysed with a localized ballooning code, BLOON. The attainment of high β is facilitated by an automated optimization search on shape and current parameters. The equilibria are calculated with a free-boundary equilibrium code using coils appropriate for the Doublet III experimental device. The optimal equilibria are characterized by broad current profiles with values of βsub(poloidal) approximately equal to 1. Experimental realization of the shapes and current profiles giving the highest β limits is explored with a 1 1/2-D transport code, which simulates the time evolution of the 2-D MHD equilibrium while calculating consistent current profiles from a 1-D transport model. Transport simulations indicate that nearly optimal shapes may be obtained provided that the currents in the field-shaping coils are appropriately programmed and the plasma current profile is sufficiently broad. Obtaining broad current profiles is possible by current ramping, neutral-beam heating, and electron-cyclotron heating. With combinations of these techniques it is possible to approach the optimum β predicted by the MHD theory. (author)

Implications for the future and recommendations for modifications to current regulations concerning virgin olive oil

Directory of Open Access Journals (Sweden)

Peri, Claudio

1994-04-01

Full Text Available The main conclusions of the FLAIR project can be summarized as follows:
1. The sensory wheel set up by the FLAIR team is proposed as a European standard to evaluate the sensory profile of extra virgin olive oil.
2. Preference studies demonstrate that the sensory profile of extra virgin olive oil should be optimized as a function of consumer expectations. Once a sensory profile has been selected, it must be used as a reference for product standardization.
3. Sensory analysis cannot be used as a legal tool for evaluating the quality or the origin of extra virgin olive oils. It is suggested that a sensory test can only be used as a legal tool if it is applied to assess the absence of defects. This implies a modification of the COI test.
4. The Good Manufacturing Practices set up by the Flair team are proposed as a European standard for process control and quality system certification.
5. Nutritional studies demonstrate that extra virgin olive oil has a noticeable in vivo antioxidant activity. This activity is related to the tocopherols and phenols content of oil and is highly varietydependent.

Determination of current and rotational transform profiles in a current-carrying stellarator using soft x-ray emissivity measurements

Science.gov (United States)

Ma, X.; Cianciosa, M. R.; Ennis, D. A.; Hanson, J. D.; Hartwell, G. J.; Herfindal, J. L.; Howell, E. C.; Knowlton, S. F.; Maurer, D. A.; Traverso, P. J.

2018-01-01

Collimated soft X-ray (SXR) emissivity measurements from multi-channel cameras on the Compact Toroidal Hybrid (CTH) tokamak/torsatron device are incorporated in the 3D equilibrium reconstruction code V3FIT to reconstruct the shape of flux surfaces and infer the current distribution within the plasma. Equilibrium reconstructions of sawtoothing plasmas that use data from both SXR and external magnetic diagnostics show the central safety factor to be near unity under the assumption that SXR iso-emissivity contours lie on magnetic flux surfaces. The reconstruction results are consistent with those using the external magnetic data and a constraint on the location of q = 1 surfaces determined from the sawtooth inversion surface extracted from SXR brightness profiles. The agreement justifies the use of approximating SXR emission as a flux function in CTH, at least within the core of the plasma, subject to the spatial resolution of the SXR diagnostics. This improved reconstruction of the central current density indicates that the current profile peakedness decreases with increasing external transform and that the internal inductance is not a relevant measure of how peaked the current profile is in hybrid discharges.

Study on possibility of plasma current profile determination using an analytical model of tokamak equilibrium

International Nuclear Information System (INIS)

Moriyama, Shin-ichi; Hiraki, Naoji

1996-01-01

The possibility of determining the current profile of tokamak plasma from the external magnetic measurements alone is investigated using an analytical model of tokamak equilibrium. The model, which is based on an approximate solution of the Grad-Shafranov equation, can set a plasma current profile expressed with four free parameters of the total plasma current, the poloidal beta, the plasma internal inductance and the axial safety factor. The analysis done with this model indicates that, for a D-shaped plasma, the boundary poloidal magnetic field prescribing the external magnetic field distribution is dependent on the axial safety factor in spite of keeping the boundary safety factor and the plasma internal inductance constant. This suggests that the plasma current profile is reversely determined from the external magnetic analysis. The possibility and the limitation of current profile determination are discussed through this analytical result. (author)

RIKEN 200 kV high current implanter for metal surface modification

International Nuclear Information System (INIS)

Iwaki, M.; Yoshida, K.; Sakudo, N.

1985-01-01

A high current, metal ion implanter was constructed in order to aid the formation of a new metastable surface alloy. This implanter, called a RIKEN 200 kV high current implanter, is a modified Lintott high current machine (Series III), which has the advantages of having its own microwave ion source and an extra target chamber. The microwave discharge ion source without a hot-filament has a comparatively long lifetime because the chloride ions and radicals in a plasma during discharge of metal chlorides might prevent metal to deposit on the inner walls of the discharge chamber by bombarding and chemically cleaning them. An extra target chamber for metal modification is able to control the surface composition by utilizing the sputtering effect of the ion beam during ion implantation. The use of this ion source and the extra target chamber is suggested to be suitable for the production of metallic ions and for the implantation into metals. The case study will be introduced for TI implantation into Fe. (orig.)

Adjoint optimization scheme for lower hybrid current rampup and profile control in Tokamak

International Nuclear Information System (INIS)

Litaudon, X.; Moreau, D.; Bizarro, J.P.; Hoang, G.T.; Kupfer, K.; Peysson, Y.; Shkarofsky, I.P.; Bonoli, P.

1992-12-01

The purpose of this work is to take into account and study the effect of the electric field profiles on the Lower Hybrid (LH) current drive efficiency during transient phases such as rampup. As a complement to the full ray-tracing / Fokker Planck studies, and for the purpose of optimization studies, we developed a simplified 1-D model based on the adjoint Karney-Fisch numerical results. This approach allows us to estimate the LH power deposition profile which would be required for ramping the current with prescribed rate, total current density profile (q-profile) and surface loop voltage. For rampup optimization studies, we can therefore scan the whole parameter space and eliminate a posteriori those scenarios which correspond to unrealistic deposition profiles. We thus obtain the time evolution of the LH power, minor radius of the plasma, volt-second consumption and total energy dissipated. Optimization can thus be performed with respect to any of those criteria. This scheme is illustrated by some numerical simulations performed with TORE-SUPRA and NET/ITER parameters. We conclude with a derivation of a simple and general scaling law for the flux consumption during the rampup phase

Simultaneous real-time control of the current and pressure profiles in JET: experiments and modelling

Energy Technology Data Exchange (ETDEWEB)

Mazon, D.; Laborde, L.; Litaudon, X.; Moreau, D.; Zabeo, L.; Joffrin, E. [Association Euratom-CEA Cadarache (DSM/DRFC), 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee; Murari, A. [Consorzio RFX Association Euratom-ENEA, Padova (Italy); Ariola, M.; Albanese, R.; Tommasi, G. de; Pironti, A. [Association Euratom-ENEA, CREATE, Napoly (Italy); Moreau, D. [EFDA-JET CSU, Culham Science Centre, Abingdon, OX (United Kingdom); Tala, T. [Euratom-Tekes Association, VTT Processes (Finland); Crisanti, F.; Pericoli-Ridolfini, V.; Tuccillo, A. [Association Euratom-ENEA, C.R. Frascati (Italy); Baar, M. de; Vries, P. de [Euratom-FOM Association, TEC Cluster, Nieuwegein (Netherlands); De la Luna, E. [Euratom-Ciemat Association (Spain); Felton, R.; Corrigan, G. [Euratom-UKAEA Association, Culham Science Centre, Abingdon (United Kingdom)

2004-07-01

Real-time control of the plasma profiles (current density, pressure and flow) is one of the major issues for sustaining internal transport barriers (ITB) in a high performance plasma, with a large bootstrap current fraction. We have recently investigated the experimental and numerical aspects of the simultaneous control of the current and pressure profiles in JET ITB discharges. The current density and the electron temperature were successfully controlled via the safety factor profile (or via its inverse the tau-profile) and the {rho}{sup *}{sub Te} profile respectively. The results of these new studies are presented. With only a limited number of actuators, the technique aims at minimizing an integral square error signal which combines the 2 profiles, rather than attempting to control plasma parameters at some given radii with great precision. The resulting fuzziness of the control scheme allows the plasma to relax towards a physically accessible non-linear state which may not be accurately known in advance, but is close enough to the requested one to provide the required plasma performance. Closed loop experiments have allow to reach different target q and {rho}{sup *}{sub Te} profiles, and to some degree, to displace the region of maximum electron temperature gradient. The control has also shown some robustness in front of rapid transients.

Calculation of the non-inductive current profile in high-performance NSTX plasmas

Science.gov (United States)

Gerhardt, S. P.; Fredrickson, E.; Gates, D.; Kaye, S.; Menard, J.; Bell, M. G.; Bell, R. E.; Le Blanc, B. P.; Kugel, H.; Sabbagh, S. A.; Yuh, H.

2011-03-01

The constituents of the current profile have been computed for a wide range of high-performance plasmas in NSTX (Ono et al 2000 Nucl. Fusion 40 557); these include cases designed to maximize the non-inductive fraction, pulse length, toroidal-β or stored energy. In the absence of low-frequency MHD activity, good agreement is found between the reconstructed current profile and that predicted by summing the independently calculated inductive, pressure-driven and neutral beam currents, without the need to invoke any anomalous beam ion diffusion. Exceptions occur, for instance, when there are toroidal Alfvén eigenmode avalanches or coupled m/n = 1/1 + 2/1 kink-tearing modes. In these cases, the addition of a spatially and temporally dependent fast-ion diffusivity can reduce the core beam current drive, restoring agreement between the reconstructed profile and the summed constituents, as well as bringing better agreement between the simulated and measured neutron emission rate. An upper bound on the fast-ion diffusivity of ~0.5-1 m2 s-1 is found in 'MHD-free' discharges, based on the neutron emission, the time rate of change in the neutron signal when a neutral beam is stepped and reconstructed on-axis current density.

Calculation of the Non-Inductive Current Profile in High-Performance NSTX Plasmas

International Nuclear Information System (INIS)

Gerhardt, S.P.; Fredrickson, E.; Gates, D.; Kaye, S.; Menard, J.; Bell, M.G.; Bell, R.E.; Le Blanc, B.P.; Kugel, H.; Sabbagh, S.A.; Yuh, H.

2011-01-01

The constituents of the current profile have been computed for a wide range of high-performance plasmas in NSTX [M. Ono, et al., Nuclear Fusion 40, 557 (2000)]; these include cases designed to maximize the non-inductive fraction, pulse length, toroidal-β, or stored energy. In the absence of low-frequency MHD activity, good agreement is found between the reconstructed current profile and that predicted by summing the independently calculated inductive, pressure-driven, and neutral beam currents, without the need to invoke any anomalous beam ion diffusion. Exceptions occur, for instance, when there are toroidal Alfven eigenmode avalanches or coupled m/n=1/1+2/1 kink-tearing modes. In these cases, the addition of a spatially and temporally dependent fast ion diffusivity can reduce the core beam current drive, restoring agreement between the reconstructed profile and the summed constituents, as well as bringing better agreement between the simulated and measured neutron emission rate. An upper bound on the fast ion diffusivity of ∼0.5-1 m 2 /sec is found in 'MHD-free' discharges, based on the neutron emission, time rate of change of the neutron signal when a neutral beam is stepped, and reconstructed on-axis current density.

Analysis of plasma equilibrium based on orbit-driven current density profile in steady-state plasma on QUEST

Energy Technology Data Exchange (ETDEWEB)

Nakamura, K., E-mail: nakamura@triam.kyushu-u.ac.jp [RIAM, Kyushu University, Kasuga 816-8580 (Japan); Alam, M.M. [IGSES, Kyushu University, Kasuga 816-8580 (Japan); Jiang, Y.Z. [Tsinghua University, Beijing 100084 (China); Mitarai, O. [Tokai University, Kumamoto 862-8652 (Japan); Kurihara, K.; Kawamata, Y.; Sueoka, M.; Takechi, M. [Japan Atomic Energy Agency, Naka 311-0193 (Japan); Hasegawa, M.; Tokunaga, K.; Araki, K.; Zushi, H.; Hanada, K.; Fujisawa, A.; Idei, H.; Nagashima, Y.; Kawasaki, S.; Nakashima, H.; Higashijima, A.; Nagata, T. [RIAM, Kyushu University, Kasuga 816-8580 (Japan); and others

2016-11-01

Highlights: • High energy particle guiding center orbit is calculated as a contour plot of conserved variable. • Current density profile is analyzed based on the orbit-driven current. • Plasma equilibrium is reconstructed by considering the hollow current profile. - Abstract: In the present RF-driven (ECCD) steady-state plasma on QUEST (B{sub t} = 0.25 T, R = 0.68 m, a = 0.40 m), plasma current seems to flow in the open magnetic surface outside of the closed magnetic surface in the low-field region according to plasma current fitting (PCF) method. We consider that the current in the open magnetic surface is due to orbit-driven current by high-energy particles in RF-driven plasma. So based on the analysis of current density profile based on the orbit-driven current, plasma equilibrium is to be calculated. We calculated high energy particles guiding center orbits as a contour plot of conserved variable in Hamiltonian formulation and considered particles initial position with different levels of energy and pitch angles that satisfy resonance condition. Then the profile of orbit-driven current is estimated by multiplying the particle density on the resonance surface and the velocity on the orbits. This analysis shows negative current near the magnetic axis and hollow current profile is expected even if pressure driven current is considered. Considering the hollow current profile shifted toward the low-field region, the equilibrium is fitted by J-EFIT coded by MATLAB.

Influence of Different Surface Modifications on the Photovoltaic Performance and Dark Current of Dye-Sensitized Solar Cells

Institute of Scientific and Technical Information of China (English)

XU Weiwei; DAI Songyuan; HU Linhua; ZHANG Changneng; XIAO Shangfeng; LUO Xiangdong; JING Weiping; WANG Kongjia

2007-01-01

The TiO2 nanoporous film photoelectrode, as a crucial component of dye-sensitized solar cells, has been investigated. The photovoltaic properties and the dark current were studied by two surface modification methods. One was to apply a compact layer between the conductive glass substrate and nanoporous TiO2 film. Another was to produce TiO2 nanoparticles among the microstructure by TiCU treatment. A suitable concentration and number of times for TiCU treatment were found in our experiment. The dark current is suppressed by surface modifications, leading to a significant improvement in the solar cells performance. An excessive concentration of TiCU will produce more surface states and introduce a larger dark current reversely. The dye is also regarded as a source of charge recombination in dark to some extent, due to an amount of surface protonations introduced by the interfacial link in the conductive glass substrate/dye interface and dye/TiO2 interface.

Comparative LC-MS/MS profiling of free and protein-bound early and advanced glycation-induced lysine modifications in dairy products

International Nuclear Information System (INIS)

Hegele, Joerg; Buetler, Timo; Delatour, Thierry

2008-01-01

Free and protein-bound forms of early and advanced glycation-induced lysine (Lys) modifications were quantified in dairy products by LC-MS/MS using a stable isotope dilution assay. The glycation profiles for N ε -fructoselysine (FL), N ε -carboxymethyllysine (CML) and pyrraline (Pyr) were monitored in raw and processed cow milk to investigate whether free glycation products could serve as fast and simple markers to assess the extent of protein glycation in dairy products. In all milk samples, the fraction of free glycation adducts was predominantly composed of advanced modifications, e.g. 8.34 ± 3.81 nmol CML per μmol of free Lys (Lys free ) and 81.5 ± 87.8 nmol Pyr μmol -1 Lys free -1 vs. 3.72 ± 1.29 nmol FL μmol -1 Lys free -1 . In contrast, the protein-bound early glycation product FL considerably outweighed the content of CML and Pyr in milk proteins of raw and processed cow milk, whereas severely heat treated milk products, e.g. condensed milk, contained a higher amount of protein-bound advanced glycation adducts. Typical values recorded for milk samples processed under mild conditions were 0.47 ± 0.08 nmol FL μmol -1 of protein-bound Lys (Lys p-b ), 0.04 ± 0.03 nmol CML μmol -1 Lys p-b -1 and 0.06 ± 0.02 nmol Pyr μmol -1 Lys p-b -1 . It was particularly noticeable, however, that mild heat treatment of raw milk, i.e. pasteurization and UHT treatment, did not significantly increase the amount of both free and protein-bound Lys modifications. In conclusion, the profiles of free and protein-bound glycation-induced Lys modifications were found to be different and a screening of free glycation adducts does, therefore, not allow for a conclusion about the protein glycation status of dairy products

Axisymmetric disruption dynamics including current profile changes in the ASDEX-Upgrade tokamak

International Nuclear Information System (INIS)

Nakamura, Y.; Pautasso, G.; Gruber, O.; Jardin, S.C.

2002-01-01

Axisymmetric MHD simulations have revealed a new driving mechanism that governs the vertical displacement event (VDE) dynamics in tokamak disruptions. A rapid flattening of the plasma current profile during the disruption plays a substantial role in dragging a single null-diverted plasma vertically towards the divertor. As a consequence, the occurrence of downward-going VDEs predominates over the upward-going ones in bottom-diverted discharges. This dragging effect, due to an abrupt change in the current profile, is absent in up-down symmetric limiter discharges. These simulation results are consistent with experiments in ASDEX-Upgrade. Together with the attractive force that arises from passive shell currents induced by the plasma current quench, the dragging effect explains many details of the VDE dynamics over the whole period of the disruptive termination. (author)

Modification of Particle Distributions by MHD Instabilities II

International Nuclear Information System (INIS)

White, Roscoe B.

2011-01-01

The modification of particle distributions by low amplitude magnetohydrodynamic modes is an important topic for magnetically confined plasmas. Low amplitude modes are known to be capable of producing significant modification of injected neutral beam profiles, and the same can be expected in burning plasmas for the alpha particle distributions. Flattening of a distribution in an island due to phase mixing and portions of phase space becoming stochastic lead to modification of the particle distribution, a process extremely rapid in the time scale of an experiment but still very long compared to the time scale of guiding center simulations. Large amplitude modes can cause profile avalanche and particle loss. Thus it is very valuable to be able to predict the temporal evolution of a particle distribution produced by a given spectrum of magnetohydrodynamic modes. In this paper we further develop and investigate the use of a new method of determining domains of phase space in which good KAM surfaces do not exist and use this method to examine a well documented case of profile modification by instabilities.

Buoyancy package for self-contained acoustic doppler current profiler mooring

Digital Repository Service at National Institute of Oceanography (India)

Venkatesan, R.; Krishnakumar, V.

A buoyancy package for self-contained Acoustic Doppler Current Profiler(SC-ADCP 1200 RD instruments USA) was designed and fabricated indigenously, for subsurface mooring in coastal waters. The system design is discussed. The design to keep SC...

Silhouette and spectral line profiles in the special modification of the Kerr black hole geometry generated by quintessential fields

Energy Technology Data Exchange (ETDEWEB)

Schee, Jan; Stuchlik, Zdenek [Silesian University in Opava, Faculty of Philosophy and Science, Institute of Physics and Research Centre for Theoretical Physics and Astrophysics, Opava (Czech Republic)

2016-11-15

We study optical effects in quintessential Kerr black hole spacetimes corresponding to the limiting case of the equation-of-state parameter ω{sub q} = -1/3 of the quintessence. In dependence on the dimensionless quintessential field parameter c, we determine the black hole silhouette and the spectral line profiles of Keplerian disks generated in this special quintessential Kerr geometry, representing an extension of the general modifications of the Kerr geometry introduced recently by Ghasemi-Nodehi and Bambi (Eur. Phys. J. C 56:290, 2016). We demonstrate that due to the influence of the parameter c, the silhouette is almost homogeneously enlarged, and the spectral line profiles are redshifted with almost conserved shape. (orig.)

Conductivity Profile Determination by Eddy Current for Shot Peened Superalloy Surfaces Toward Residual Stress Assessment

International Nuclear Information System (INIS)

Shen, Y.; Lo, C. C. H.; Frishman, A. M.; Lee, C.; Nakagawa, N.

2007-01-01

This paper describes an eddy current model-based method for inverting near-surface conductivity deviation profiles of surface treated materials from swept-high frequency eddy current (SHFEC) data. This work forms part of our current research directed towards the development of an electromagnetic nondestructive technique for assessing residual stress of shot-peened superalloy components. The inversion procedure is based on the use of a parameterized function to describe the near-surface conductivity as a function of depth for a shot-peened surface, and the laterally uniform multi-layer theory of Cheng, Dodd and Deeds to calculate the resulting coil impedance deviations. The convergence of the inversion procedure has been tested against synthesized eddy current data. As a demonstration, the conductivity deviation profiles of a series of Inconel 718 specimens, shot peened at various Almen intensities, have been obtained by inversion. Several consistency tests were conducted to examine the reliability of the inverted conductivity profiles. The results show that conductivity deviation profiles can be reliably determined from SHFEC data within the accuracy of the current measurement system

Cool Down Experiences with the SST-1 Helium Cryogenics System before and after Current Feeders System Modification

Science.gov (United States)

Patel, R.; Panchal, P.; Panchal, R.; Tank, J.; Mahesuriya, G.; Sonara, D.; Srikanth, G. L. N.; Garg, A.; Bairagi, N.; Christian, D.; Patel, K.; Shah, P.; Nimavat, H.; Sharma, R.; Patel, J. C.; Gupta, N. C.; Prasad, U.; Sharma, A. N.; Tanna, V. L.; Pradhan, S.

The SST-1 machine comprises a superconducting magnet system (SCMS), which includes TF and PF magnets. In order to charge the SCMS, we need superconducting current feeders consisting of SC feeders and vapor cooled current leads (VCCLs). We have installed all 10 (+/-) pairs of VCCLs for the TF and PF systems. While conducting initial engineering validation of the SST-1 machine, our prime objective was to produce circular plasma using only the TF system. During the SST-1 campaign I to VI, we have to stop the PF magnets cooling in order to get the cryo- stable conditions for current charging of the TF magnets system. In that case, the cooling of the PF current leads is not essential. It has been also observed that after aborting the PF system cooling, there was a limited experimental window of TF operation. Therefore, in the recent SST-1 campaign-VII, we removed the PF current leads (9 pairs) and kept only single (+/-) pair of the 10,000 A rated VCCLs to realize the charging of the TF system for the extended window of operation. We have observed a better cryogenic stability in the TF magnets after modifications in the CFS. In this paper, we report the comparison of the cool down performance for the SST-1 machine operation before and after modifications of the current feeders system.

A current profile model for magnetic analysis of the start-up phase of toroidal plasmas driven by electron cyclotron heating and current drive

International Nuclear Information System (INIS)

Yoshinaga, T.; Uchida, M.; Tanaka, H.; Maekawa, T.

2007-01-01

An estimation model of plasma current density distribution for the start-up phase of toroidal plasmas generated by electron cyclotron heating (ECH) in the low aspect ratio torus experiment device is presented. The model assumes a power law parabolic current profile having seven fitting parameters. Its position, extent and broadness (or steepness) are fitted by adjusting these parameters to the observed magnetic flux signals. The adequacy of the model has been examined and confirmed by comparisons of the reconstructed current profiles and the resultant poloidal flux surfaces with the plasma images at visible light range at various stages of start-up discharges, including both the initial open field phase, the subsequent closed field phase, the current decay phase after ECH is turned off and also by a current-profile limiting experiment. This method may be useful for the study of non-inductive start-up experiments by ECH, where there is no appropriate MHD constraint on the current distribution as that in the full tokamak discharge plasmas

Algorithm Validation of the Current Profile Reconstruction of EAST Based on Polarimeter/Interferometer

International Nuclear Information System (INIS)

Qian Jinping; Ren Qilong; Wan Baonian; Liu Haiqin; Zeng Long; Luo Zhengping; Chen Dalong; Shi Tonghui; Sun Youwen; Shen Biao; Xiao Bingjia; Lao, L. L.; Hanada, K.

2015-01-01

The method of plasma current profile reconstruction using the polarimeter/interferometer (POINT) data from a simulated equilibrium is explored and validated. It is shown that the safety factor (q) profile can be generally reconstructed from the external magnetic and POINT data. The reconstructed q profile is found to reasonably agree with the initial equilibriums. Comparisons of reconstructed q and density profiles using the magnetic data and the POINT data with 3%, 5% and 10% random errors are investigated. The result shows that the POINT data could be used to a reasonably accurate determination of the q profile. (fusion engineering)

Real-time evaluation of electron and current density profile parameters on TEXTOR

International Nuclear Information System (INIS)

Bruessau, W.D.; Soltwisch, H.

1985-08-01

The shapes of electron and current density profiles are monitored in real-time mode in order to get rapid qualitative information on the development of a TEXTOR tokamak plasma. The profiles are described by form parameters which relate to the signals of a 9-channel FIR-polari/interferometer in simple mathematical formulae. These profile parameters are obtained by real-time conversion of measured quantities for display on a storage oscilloscope or on a chart recorder. The application of the parameters is demonstrated in some examples. (orig.)

Shear optimization experiments with current profile control on JET

International Nuclear Information System (INIS)

1997-01-01

A record performance on JET has been obtained with shear optimization scenarios. A neutron yield of 5.6x10 16 s -1 in deuterium discharges, and a global energy confinement improvement above the ITER-89 L-mode scaling with H ≤ 2.5 in L-mode and H ≤ 3 in H-mode have been achieved. The tailoring of plasma current, density and heating power waveforms and current profile control with lower hybrid current drive and ICRF phasing have been essential. Internal energy, particle and momentum transport barriers develop spontaneously upon heating above a threshold power of about 15 MW with neutral beams and ICRH into a low-density target plasma, with a wide central region of slightly negative or flat magnetic shear with q > 1 everywhere. An additional H-mode transition can also raise the pressure in the region between internal and edge transport barriers. The ion heat conductivity falls to the neoclassical level in the improved core confinement region. Pressure profile control through power deposition feedback control makes it possible to work close to the marginal stability boundary for pressure-driven MHD modes. First experiments in deuterium/tritium plasmas, with up to 75% tritium target concentration, have established internal transport barriers already with heating powers at the lowest threshold of pure deuterium plasmas, resulting in a fusion power output of P fusion = 2 MW. (author)

Current Evidence of Gait Modification with Real-time Biofeedback to Alter Kinetic, Temporospatial, and Function-Related Outcomes: A Review

Directory of Open Access Journals (Sweden)

Oladipo Eddo

2017-07-01

Full Text Available Background: Gait retraining using real-time biofeedback (RTB may have positive outcomes in decreasing knee adduction moment (KAM in healthy individuals and has shown equal likelihood in patients with knee osteoarthritis (OA. Currently, there is no consensus regarding the most effective gait modification strategy, mode of biofeedback or treatment dosage. Objective: The purpose of this review was: i to assess if gait retraining interventions using RTB are valuable to reduce KAM, pain, and improve function in individuals with knee osteoarthritis, ii to evaluate the effectiveness of different gait modifications and modes of RTB in reducing KAM in healthy individuals, and iii to assess the impact of gait retraining interventions with RTB on other variables that may affect clinical outcomes. Methods: Seven electronic databases were searched using five search terms. Studies that utilized any form of gait retraining with RTB to improve one or a combination of the following measures were included: KAM, knee pain, and function. Twelve studies met the inclusion criteria, evaluating eleven distinctive gait modifications and three modes of RTB. Results: All but one study showed positive outcomes. Self-selected and multi-parameter gait modifications showed the greatest reductions in KAM with visual and haptic RTB being more effective than auditory. Conclusions: Current evidence suggests that gait modification using RTB can Positively alter KAM in asymptomatic and symptomatic participants. However, the existing literature is limited and of low quality, with the optimal combination strategies remaining unclear (gait and biofeedback mode. Future studies should employ randomized controlled study designs to compare the effects of different gait modification strategies and biofeedback modes on individuals with knee OA.

Feedback control of current drive by using hybrid wave in tokamaks

International Nuclear Information System (INIS)

Wijnands, T.J.; CEA Centre d'Etudes de Cadarache, 13 - Saint-Paul-lez-Durance

1997-03-01

This work is focussed on an important and recent development in present day Controlled Nuclear Fusion Research and Tokamaks. The aim is to optimise the energy confinement for a certain magnetic configuration by adapting the radial distribution of the current. Of particular interest are feedback control scenarios with stationary modifications of the current profile using current, driven by Lower Hybrid waves. A new feedback control system has been developed for Tore Supra and has made a large number of new operation scenarios possible. In one of the experiments described here, there is no energy exchange between the poloidal field system and the plasma, the current is controlled by the power of the Lower Hybrid waves while the launched wave spectrum is used to optimise the current profile shape and the energy confinement. (author)

Comparative LC-MS/MS profiling of free and protein-bound early and advanced glycation-induced lysine modifications in dairy products

Energy Technology Data Exchange (ETDEWEB)

Hegele, Joerg [Nestle Research Centre, Nestec Ltd., Vers-chez-les-Blanc, CH-1000 Lausanne 26 (Switzerland)], E-mail: joerg.hegele@rdls.nestle.com; Buetler, Timo; Delatour, Thierry [Nestle Research Centre, Nestec Ltd., Vers-chez-les-Blanc, CH-1000 Lausanne 26 (Switzerland)

2008-06-09

Free and protein-bound forms of early and advanced glycation-induced lysine (Lys) modifications were quantified in dairy products by LC-MS/MS using a stable isotope dilution assay. The glycation profiles for N{sup {epsilon}}-fructoselysine (FL), N{sup {epsilon}}-carboxymethyllysine (CML) and pyrraline (Pyr) were monitored in raw and processed cow milk to investigate whether free glycation products could serve as fast and simple markers to assess the extent of protein glycation in dairy products. In all milk samples, the fraction of free glycation adducts was predominantly composed of advanced modifications, e.g. 8.34 {+-} 3.81 nmol CML per {mu}mol of free Lys (Lys{sub free}) and 81.5 {+-} 87.8 nmol Pyr {mu}mol{sup -1} Lys{sub free}{sup -1} vs. 3.72 {+-} 1.29 nmol FL {mu}mol{sup -1} Lys{sub free}{sup -1}. In contrast, the protein-bound early glycation product FL considerably outweighed the content of CML and Pyr in milk proteins of raw and processed cow milk, whereas severely heat treated milk products, e.g. condensed milk, contained a higher amount of protein-bound advanced glycation adducts. Typical values recorded for milk samples processed under mild conditions were 0.47 {+-} 0.08 nmol FL {mu}mol{sup -1} of protein-bound Lys (Lys{sub p-b}), 0.04 {+-} 0.03 nmol CML {mu}mol{sup -1} Lys{sub p-b}{sup -1} and 0.06 {+-} 0.02 nmol Pyr {mu}mol{sup -1} Lys{sub p-b}{sup -1}. It was particularly noticeable, however, that mild heat treatment of raw milk, i.e. pasteurization and UHT treatment, did not significantly increase the amount of both free and protein-bound Lys modifications. In conclusion, the profiles of free and protein-bound glycation-induced Lys modifications were found to be different and a screening of free glycation adducts does, therefore, not allow for a conclusion about the protein glycation status of dairy products.

Simulations of enhanced reversed shear TFTR discharges with lower hybrid current drive

International Nuclear Information System (INIS)

Kesner, J.; Bateman, G.

1996-01-01

The BALDUR based BBK code permits predictive simulations of time-dependent tokamak discharges and has the capability to include neutral beam heating, pellet injection, bootstrap currents and lower hybrid current drive. BALDUR contains a theory based multi-regime transport model and previous work has shown excellent agreement with both L-mode and supershot TFTR discharges. These simulations reveal that core transport is dominated by η i and trapped electron modes and the outer region by resistive ballooning. We simulate enhanced reverse shear discharges by beginning with a supershot simulation with a reversed shear profile. Similarly to the TFTR experiments the reversed shear profile is obtained through the programming of the current during startup and the freezing in of these profiles by subsequent heating. At the time of transition into the enhanced confinement regime we turn off the η i and trapped-electron mode transport. We examine the further modification of the plasma current profile that can be obtained with the application of lower hybrid current drive. The results of these simulations will be discussed

Theory and experiments on RF plasma heating, current drive and profile control in TORE SUPRA

International Nuclear Information System (INIS)

Moreau, D.

1994-01-01

This paper reviews the main experimental and theoretical achievements related to the study of RF heating and non-inductive current drive and particularly phenomena related to the current density profile control and the potentiality of producing stationary enhanced performance regimes: description of the Lower Hybrid (LH) and Ion Cyclotron Resonant Frequency (ICRF) systems; long pulse coupling performance of the RF systems; observation of the transition to the so-called ''stationary LHEP regime'' in which the (flat) central current density and (peaked) electron temperature profiles are fully decoupled; experiments on ICRF sawtooth stabilization with the combined effect of LHCD modifying the current density profile; diffusion of fast electrons generated by LH waves; ramp-up experiments in which the LH power provided a significant part of the resistive poloidal flux and flux consumption scaling; theory of spectral wave diffusion and multipass absorption; fast wave current drive modelling with the Alcyon full wave code; a reflector LH antenna concept. 18 figs., 48 refs

Effect of current tobacco consumption on the male reproductive hormone profile.

Science.gov (United States)

Blanco-Muñoz, Julia; Lacasaña, Marina; Aguilar-Garduño, Clemente

2012-06-01

The knowledge about the effect of cigarette smoking on the male reproductive function is still limited. The objective of this study was to evaluate the association between active exposure to tobacco smoke and the male reproductive hormone profile in a group of 136 Mexican flower growers. Serum levels of FSH, LH, prolactin, total testosterone, Inhibin B and estradiol were measured using enzyme-linked immunoabsorbent assay. Weight and height were also measured and a structured questionnaire was applied to get information on sociodemographic characteristics, clinical and work history and alcohol and tobacco consumption (current smoking habit and number of cigarettes smoked per day). Based on this information tobacco consumption was divided into four categories: never-smokers, ex-smokers, current smokers under five cigarettes/day and current smokers over or equal to five cigarettes/day. Using the group of never-smokers as reference and after adjusting for potential confounders, current smokers of five or more cigarettes/day showed significantly higher levels of LH (β=0.33, p=0.01), prolactin (β=0.18, p=0.03) and testosterone (β=0.21, p=0.02). Current smokers of less than five cigarettes/day also showed higher levels of prolactin (β=0.12, p=0.03) and testosterone (β=0.18, pconsumption may act as an endocrine disruptor on the male hormone profile. Copyright © 2012 Elsevier B.V. All rights reserved.

Core fluctuations and current profile dynamics in the MST reversed-field pinch

International Nuclear Information System (INIS)

Brower, D.L.; Ding, W.X.; Lei, J.

2003-01-01

First measurements of the current density profile, magnetic field fluctuations and electrostatic (e.s.) particle flux in the core of a high-temperature reversed-field pinch (RFP) are presented. We report three new results: (1) The current density peaks during the slow ramp phase of the sawtooth cycle and flattens promptly at the crash. Profile flattening can be linked to magnetic relaxation and the dynamo which is predicted to drive anti-parallel current in the core. Measured core magnetic fluctuations are observed to increases four-fold at the crash. Between sawtooth crashes, measurements indicate the particle flux driven by e.s. fluctuations is too small to account for the total radial particle flux. (2) Core magnetic fluctuations are observed to decrease at least twofold in plasmas where energy confinement time improves ten-fold. In this case, the radial particle flux is also reduced, suggesting core e.s. fluctuation-induced transport may play role in confinement. (3) The parallel current density increases in the outer region of the plasma during high confinement, as expected, due to the applied edge parallel electric field. However, the core current density also increases due to dynamo reduction and the emergence of runaway electrons. (author)

The profile of the domain walls in amorphous glass-covered microwires

Energy Technology Data Exchange (ETDEWEB)

Beck, F.; Rigue, J.N. [Universidade Federal de Santa Maria, Campus Cachoeira do Sul, RS (Brazil); Carara, M., E-mail: carara@smail.ufsm.br [Departamento de Física, Universidade Federal de Santa Maria, Santa Maria, RS (Brazil)

2017-08-01

Highlights: • Glass-covered microwires with positive magnetostriction were studied. • The single domain wall dynamics was studied under different conditions. • We have evaluated the profile and shape of the moving domain walls. • The domain wall evolves from a bell shape to a parabolic one when a current is applied. - Abstract: We have studied the domain wall dynamics in Joule-annealed amorphous glass-covered microwires with positive magnetostriction in the presence of an electric current, in order to evaluate the profile and shape of the moving domain wall. Such microwires are known to present magnetic bi-stability when axially magnetized. The single domain wall dynamics was evaluated under different conditions, under an axially applied stress and an electric current. We have observed the well known increasing of the domain wall damping with the applied stress due to the increase in the magnetoelastic anisotropy and, when the current is applied, depending on the current intensity and direction, a modification on the axial domain wall damping. When the orthogonal motion of the domain wall is considered, we have observed that the associated velocity present a smaller dependence on the applied current intensity. It was observed a modification on both the domain wall shape and length. In a general way, the domain wall evolves from a bell shape to a parabolic shape as the current intensity is increased. The results were explained in terms of the change in the magnetic energy promoted by the additional Oersted field.

A simulation study on burning profile tailoring of steady state, high bootstrap current tokamaks

International Nuclear Information System (INIS)

Nakamura, Y.; Takei, N.; Tobita, K.; Sakamoto, Y.; Fujita, T.; Fukuyama, A.; Jardin, S.C.

2007-01-01

From the aspect of fusion burn control in steady state DEMO plant, the significant challenges are to maintain its high power burning state of ∝3-5 GW without burning instability, hitherto well-known as ''thermal stability'', and also to keep its desired burning profile relevant with internal transport barrier (ITB) that generates high bootstrap current. The paper presents a simulation modeling of the burning stability coupled with the self-ignited fusion burn and the structure-formation of the ITB. A self-consistent simulation, including a model for improved core energy confinement, has pointed out that in the high power fusion DEMO plant there is a close, nonlinear interplay between the fusion burnup and the current source of non-inductive, ITB-generated bootstrap current. Consequently, as much distinct from usual plasma controls under simulated burning conditions with lower power (<<1 GW), the selfignited fusion burn at a high power burning state of ∝3-5 GW becomes so strongly selforganized that any of external means except fuelling can not provide the effective control of the stable fusion burn.It is also demonstrated that externally applied, inductive current perturbations can be used to control both the location and strength of ITB in a fully noninductive tokamak discharge. We find that ITB structures formed with broad noninductive current sources such as LHCD are more readily controlled than those formed by localized sources such as ECCD. The physics of the inductive current is well known. Consequently, we believe that the controllability of the ITB is generic, and does not depend on the details of the transport model (as long as they can form an ITB for sufficiently reversed magnetic shear q-profile). Through this external control of the magnetic shear profile, we can maintain the ITB strength that is otherwise prone to deteriorate when the bootstrap current increases. These distinguishing capabilities of inductive current perturbation provide steady

Measurement of current drive profile using electron cyclotron wave attenuation near the O-mode cutoff

International Nuclear Information System (INIS)

Fidone, I.; Meyer, R.L.; Caron, X.

1992-01-01

A method for determining the radial profile of the lower-hybrid current drive in tokamaks using electron cyclotron attenuation of the O mode for frequencies ω near the cutoff frequency is discussed. The basic idea is that, for a given wave frequency, the cutoff plays the role of a spatial filter selecting a variable portion of the noninductive current. It is shown that the incremental attenuation resulting from a small increase of ω displays specific features related to the current density near the cutoff point. Using the relation between the wave damping and the current density, it is possible to determine the radial profile of the current drive from the wave attenuation measurements. A numerical application is also presented for plasma parameters in the reactor regime

A Profile of Current Employee Training Practices in Selected Businesses and Industries in Southwest Virginia

OpenAIRE

Hundley, Katrina M.

2003-01-01

The purposes of this study were to (a) establish a profile of the current training practices of selected businesses and industries in Southwest Virginia; (b) identify the type of training methods these companies are choosing -- such as traditional classroom training or web-based training programs, and (c) identify how the training methods are selected. This profile established baseline data for current business and industry employee training programs. The population of this study include...

Complementary Medicine, Exercise, Meditation, Diet, and Lifestyle Modification for Anxiety Disorders: A Review of Current Evidence

Directory of Open Access Journals (Sweden)

J. Sarris

2012-01-01

Full Text Available Use of complementary medicines and therapies (CAM and modification of lifestyle factors such as physical activity, exercise, and diet are being increasingly considered as potential therapeutic options for anxiety disorders. The objective of this metareview was to examine evidence across a broad range of CAM and lifestyle interventions in the treatment of anxiety disorders. In early 2012 we conducted a literature search of PubMed, Scopus, CINAHL, Web of Science, PsycInfo, and the Cochrane Library, for key studies, systematic reviews, and metaanalyses in the area. Our paper found that in respect to treatment of generalized anxiety or specific disorders, CAM evidence revealed current support for the herbal medicine Kava. One isolated study shows benefit for naturopathic medicine, whereas acupuncture, yoga, and Tai chi have tentative supportive evidence, which is hampered by overall poor methodology. The breadth of evidence does not support homeopathy for treating anxiety. Strong support exists for lifestyle modifications including adoption of moderate exercise and mindfulness meditation, whereas dietary improvement, avoidance of caffeine, alcohol, and nicotine offer encouraging preliminary data. In conclusion, certain lifestyle modifications and some CAMs may provide a beneficial role in the treatment of anxiety disorders.

Magnetically filtered Faraday probe for measuring the ion current density profile of a Hall thruster

International Nuclear Information System (INIS)

Rovey, Joshua L.; Walker, Mitchell L.R.; Gallimore, Alec D.; Peterson, Peter Y.

2006-01-01

The ability of a magnetically filtered Faraday probe (MFFP) to obtain the ion current density profile of a Hall thruster is investigated. The MFFP is designed to eliminate the collection of low-energy, charge-exchange (CEX) ions by using a variable magnetic field as an ion filter. In this study, a MFFP, Faraday probe with a reduced acceptance angle (BFP), and nude Faraday probe are used to measure the ion current density profile of a 5 kW Hall thruster operating over the range of 300-500 V and 5-10 mg/s. The probes are evaluated on a xenon propellant Hall thruster in the University of Michigan Large Vacuum Test Facility at operating pressures within the range of 4.4x10 -4 Pa Xe (3.3x10 -6 Torr Xe) to 1.1x10 -3 Pa Xe (8.4x10 -6 Torr Xe) in order to study the ability of the Faraday probe designs to filter out CEX ions. Detailed examination of the results shows that the nude probe measures a greater ion current density profile than both the MFFP and BFP over the range of angular positions investigated for each operating condition. The differences between the current density profiles obtained by each probe are attributed to the ion filtering systems employed. Analysis of the results shows that the MFFP, operating at a +5 A solenoid current, provides the best agreement with flight-test data and across operating pressures

Electron and ion heat transport with lower hybrid current drive and neutral beam injection heating in ASDEX

International Nuclear Information System (INIS)

Soeldner, F.X.; Pereverzev, G.V.; Bartiromo, R.; Fahrbach, H.U.; Leuterer, F.; Murmann, H.D.; Staebler, A.; Steuer, K.H.

1993-01-01

Transport code calculations were made for experiments with the combined operation of lower hybrid current drive and heating and of neutral beam injection heating on ASDEX. Peaking or flattening of the electron temperature profile are mainly explained by modifications of the MHD induced electron heat transport. They originate from current profile changes due to lower hybrid and neutral beam current drive and to contributions from the bootstrap current. Ion heat transport cannot be described by one single model for all heating scenarios. The ion heat conductivity is reduced during lower hybrid heated phases with respect to Ohmic and neutral beam heating. (author). 13 refs, 5 figs

Sawtooth control by on-axis electron cyclotron current drive on the WT-3 tokamak

International Nuclear Information System (INIS)

Asakawa, M.; Tanabe, K.; Nakayama, A.; Watanabe, M.; Nakamura, M.; Tanaka, H.; Maekawa, T.; Terumichi, Y.

1999-01-01

The experiments on control of sawtooth oscillations (STO) by electron cyclotron current drive (ECCD) have been performed on the WT-3 tokamak. Stabilization and excitation of STO are observed for counter-ECCD and co-ECCD, respectively, when the position of the power deposition is located inside the inversion radius. These results are due to the modification of the current profile near the magnetic axis. (author)

Control of the radial electric field shear by modification of the magnetic field configuration in LHD

International Nuclear Information System (INIS)

Ida, K.; Yoshinuma, M.; Yokoyama, M.

2005-01-01

Control of the radial electric field, E r , is considered to be important in helical plasmas, because the radial electric field and its shear are expected to reduce neoclassical and anomalous transport, respectively. In general, the radial electric field can be controlled by changing the collisionality, and positive or negative electric fields have been obtained by decreasing or increasing the electron density, respectively. Although the sign of the radial electric field can be controlled by changing the collisionality, modification of the magnetic field is required to achieve further control of the radial electric field, especially to produce a strong radial electric field shear. In the Large Helical Device (LHD) the radial electric field profiles are shown to be controlled by the modification of the magnetic field by (1) changing the radial profile of the effective helical ripples, ε h (2) creating a magnetic island with an external perturbation field coil and (3) changing the local island divertor coil current

Control of the radial electric field shear by modification of the magnetic field configuration in LHD

International Nuclear Information System (INIS)

Ida, K.; Yoshinuma, M.; Yokoyama, M.

2005-01-01

Control of the radial electric field, E γ , is considered to be important in helical plasmas, because the radial electric field and its shear are expected to reduce neoclassical and anomalous transport, respectively. In general, the radial electric field can be controlled by changing the collisionality, and positive or negative electric field have been obtained by decreasing or increasing the electron density, respectively. Although the sign of the radial electric field can be controlled by changing the collisionality, modification of the magnetic field is required to achieve further control of the radial electric field, especially producing a strong radial electric field shear. In the Large Helical Device (LHD) the radial electric field profiles are shown to be controlled by the modification of the magnetic field by 1) changing the radial profile of the helical ripples, ε h , 2) creating a magnetic island with an external perturbation field coil and 3) changing the local island divertor coil current. (author)

Current Profile and Magnetic Structure Measurements through Tangential Soft X-Ray Imaging in Compact Tori

International Nuclear Information System (INIS)

Fonck, Raymond J.

2004-01-01

This report describes the fabrication and tests of a tangentially imaging soft X-ray (SXR) camera diagnostic for fusion energy plasma research. It can be used for the determination of the current distribution in strongly shaped toroidal magnetically confined plasmas, such as those found in spherical tori or advanced tokamaks. It included the development of both an appropriate imaging SXR camera and image analysis techniques necessary to deduce the plasma shape and current distribution. The basic camera concept consists of a tangentially viewing pinhole imaging system with thin-film SXR filters, a scintillator screen to provide SXR to visible conversion, a fast shuttering system, and an sensitive visible camera imaging device. The analysis approach consists of integrating the 2-D SXR image data into a Grad-Shafranov toroidal equilibrium solver code to provide strong constraints on the deduced plasma current and pressure profiles. Acceptable sensitivity in the deduced current profile can be obtained if the relative noise in the measured image can be kept in the range of 1% or less. Tests on the Pegasus Toroidal Experiment indicate very flat safety factor profiles in the plasma interior

Resistive flux saving and current profile control during lower hybrid waves assisted current rise in TORE SUPRA

International Nuclear Information System (INIS)

van Houtte, D.; Hoang, G.T.; Joffrin, E.; Lecoustey, P.; Moreau, D.; Parlange, F.; Tonon, G.; Vallet, J.C.

1992-01-01

Resistive flux saving at densities n e = (1 - 2) x 10 19 m -3 has been studied. High flux saving efficiency (0.7 x 10 13 Wb/J/m -1 ) can be achieved for a low rf power (P LH = 0.5 MW) due to the beneficial effect of the electric field on the suprathermal electrons. However for power higher than 1 MW, the efficiency is 0.25 x 10 13 Wb/J/m -1 . This flux saving efficiency is comparable to the one obtained during the flat top phase. The application of the LH power during a low density current ramp-up tends to peak the electron temperature and current density profiles. The rf power level, the parallel wavenumber and the current ramp rate allow to control the trajectories of the plasma discharges during the current rise inside the MHD stable domain

Modification Semantics in Now-Relative Databases

DEFF Research Database (Denmark)

Torp, Kristian; Jensen, Christian Søndergaard; Snodgrass, R. T.

2004-01-01

Most real-world databases record time-varying information. In such databases, the notion of ??the current time,?? or NOW, occurs naturally and prominently. For example, when capturing the past states of a relation using begin and end time columns, tuples that are part of the current state have some...... past time as their begin time and NOW as their end time. While the semantics of such variable databases has been described in detail and is well understood, the modification of variable databases remains unexplored. This paper defines the semantics of modifications involving the variable NOW. More...... specifically,  the problems with modifications in the presence of NOW are explored, illustrating that the main problems are with modifications of tuples that reach into the future. The paper defines the semantics of modifications?including insertions, deletions, and updates?of databases without NOW, with NOW...

Surface modification of steels and magnesium alloy by high current pulsed electron beam

Science.gov (United States)

Hao, Shengzhi; Gao, Bo; Wu, Aimin; Zou, Jianxin; Qin, Ying; Dong, Chuang; An, Jian; Guan, Qingfeng

2005-11-01

High current pulsed electron beam (HCPEB) is now developing as a useful tool for surface modification of materials. When concentrated electron flux transferring its energy into a very thin surface layer within a short pulse time, superfast processes such as heating, melting, evaporation and consequent solidification, as well as dynamic stress induced may impart the surface layer with improved physico-chemical and mechanical properties. This paper presents our research work on surface modification of steels and magnesium alloy with HCPEB of working parameters as electron energy 27 keV, pulse duration ∼1 μs and energy density ∼2.2 J/cm2 per pulse. Investigations performed on carbon steel T8, mold steel D2 and magnesium alloy AZ91HP have shown that the most pronounced changes of phase-structure state and properties occurring in the near-surface layers, while the thickness of the modified layer with improved microhardness (several hundreds of micrometers) is significantly greater than that of the heat-affected zone. The formation mechanisms of surface cratering and non-stationary hardening effect in depth are discussed based on the elucidation of non-equilibrium temperature filed and different kinds of stresses formed during pulsed electron beam melting treatment. After the pulsed electron beam treatments, samples show significant improvements in measurements of wear and corrosion resistance.

Surface modification of steels and magnesium alloy by high current pulsed electron beam

International Nuclear Information System (INIS)

Hao, Shengzhi; Gao, Bo; Wu, Aimin; Zou, Jianxin; Qin, Ying; Dong, Chuang; An, Jian; Guan, Qingfeng

2005-01-01

High current pulsed electron beam (HCPEB) is now developing as a useful tool for surface modification of materials. When concentrated electron flux transferring its energy into a very thin surface layer within a short pulse time, superfast processes such as heating, melting, evaporation and consequent solidification, as well as dynamic stress induced may impart the surface layer with improved physico-chemical and mechanical properties. This paper presents our research work on surface modification of steels and magnesium alloy with HCPEB of working parameters as electron energy 27 keV, pulse duration ∼1 μs and energy density ∼2.2 J/cm 2 per pulse. Investigations performed on carbon steel T8, mold steel D2 and magnesium alloy AZ91HP have shown that the most pronounced changes of phase-structure state and properties occurring in the near-surface layers, while the thickness of the modified layer with improved microhardness (several hundreds of micrometers) is significantly greater than that of the heat-affected zone. The formation mechanisms of surface cratering and non-stationary hardening effect in depth are discussed based on the elucidation of non-equilibrium temperature filed and different kinds of stresses formed during pulsed electron beam melting treatment. After the pulsed electron beam treatments, samples show significant improvements in measurements of wear and corrosion resistance

Measurement of current drive profile using electron cyclotron wave attenuation near the O-mode cut-off

International Nuclear Information System (INIS)

Fidone, I.

1991-01-01

A method for determining the radial profile of the lower-hybrid current drive in tokamaks uing electron-cyclotron attenuation of the O-mode for frequencies ω near the cut-off frequency is discussed. The basic idea is that for a given wave frequency, the cut-off plays the role of a spatial filter selecting a variable portion of the non-inductive current. It is shown that the incremental attenuation resulting from a small increase of ω displays specific features related to the current density near the cut-off point. Using the relation between the wave damping and the current density it is possible to determine the radial profile of the current drive from the wave attenuation measurements. A numerical application is also presented for plasma parameters in the reactor regime

Current profile control experiments in EXTRAP T2R

Science.gov (United States)

Brunsell, P.; Cecconello, M.; Drake, J.; Franz, P.; Malmberg, J. A.; Marrelli, L.; Martin, P.; Spizzo, G.

2002-11-01

EXTRAP T2R is a high aspect ratio (R=1.24 m, a = 0.183 m) reversed-field pinch device, characterised by a double, thin shell system. The simultaneous presence of many m=1, |n| > 11 tearing modes is responsible for a magnetic field turbulence, which is believed to produce the rather high energy and particle transport that is observed in this type of magnetic configuration. In this paper first results from current profile control experiments (PPCD) in a thin shell device are shown. When an edge poloidal electric field is transiently applied, an increase of the electron temperature and of the electron density is seen, which is consistent with an increase of the thermal content of the plasma. At the same time, the soft x-ray emission, measured with a newly installed miniaturised camera, shows a peaking of the profile in the core. Furthermore, the amplitudes of the m=1 tearing modes are reduced and and the rotation velocities increase during PPCD, which is also consistent with a reduction of magnetic turbulence and a heating of the plasma

Model-based Optimization and Feedback Control of the Current Density Profile Evolution in NSTX-U

Science.gov (United States)

Ilhan, Zeki Okan

Nuclear fusion research is a highly challenging, multidisciplinary field seeking contributions from both plasma physics and multiple engineering areas. As an application of plasma control engineering, this dissertation mainly explores methods to control the current density profile evolution within the National Spherical Torus eXperiment-Upgrade (NSTX-U), which is a substantial upgrade based on the NSTX device, which is located in Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ. Active control of the toroidal current density profile is among those plasma control milestones that the NSTX-U program must achieve to realize its next-step operational goals, which are characterized by high-performance, long-pulse, MHD-stable plasma operation with neutral beam heating. Therefore, the aim of this work is to develop model-based, feedforward and feedback controllers that can enable time regulation of the current density profile in NSTX-U by actuating the total plasma current, electron density, and the powers of the individual neutral beam injectors. Motivated by the coupled, nonlinear, multivariable, distributed-parameter plasma dynamics, the first step towards control design is the development of a physics-based, control-oriented model for the current profile evolution in NSTX-U in response to non-inductive current drives and heating systems. Numerical simulations of the proposed control-oriented model show qualitative agreement with the high-fidelity physics code TRANSP. The next step is to utilize the proposed control-oriented model to design an open-loop actuator trajectory optimizer. Given a desired operating state, the optimizer produces the actuator trajectories that can steer the plasma to such state. The objective of the feedforward control design is to provide a more systematic approach to advanced scenario planning in NSTX-U since the development of such scenarios is conventionally carried out experimentally by modifying the tokamak's actuator

Identification and real time control of current profile in Tore-supra: algorithms and simulation; Identification et controle en temps reel du profil de courant dans Tore Supra: algorithmes et simulations

Energy Technology Data Exchange (ETDEWEB)

Houy, P

1999-10-15

The aim of this work is to propose a real-time control of the current profile in order to achieve reproducible operating modes with improved energetic confinement in tokamaks. The determination of the profile is based on measurements given by interferometry and polarimetry diagnostics. Different ways to evaluate and improve the accuracy of these measurements are exposed. The position and the shape of a plasma are controlled by the poloidal system that forces them to cope with standard values. Gas or neutral ions or ice pellet or extra power injection are technical means used to control other plasma parameters. These controls are performed by servo-controlled loops. The poloidal system of Tore-supra is presented. The main obstacle to a reliable determination of the current profile is the fact that slightly different Faraday angles lead to very different profiles. The direct identification method that is exposed in this work, gives the profile that minimizes the square of the margin between measured and computed values. The different algorithms proposed to control current profiles on Tore-supra have been validated by using a plasma simulation. The code Cronos that solves the resistive diffusion equation of current has been used. (A.C.)

LHCD current profile control experiments towards steady state improved confinement on JT-60U

International Nuclear Information System (INIS)

Ide, S.; Naito, O.; Oikawa, T.; Fujita, T.; Kondoh, T.; Seki, M.; Ushigusa, K.

2001-01-01

In JT-60U lower hybrid current drive (LHCD) experiments, a reversed magnetic shear configuration that was accompanied by the internal transport barriers was successfully maintained by means of LHCD almost in the full current drive quasi-steady state for 4.7 s. The normalized beta was kept near 1 and the neutron emission rate was almost steady as well indicating no accumulation of impurities into the plasma. Diagnostics data showed that all the profiles of the electron and ion temperatures, the electron density and the current profile were almost unchanged during the LHCD phase. Moreover, capability of LHCD in H-mode plasmas has been also investigated. It was found that the lower hybrid waves can be coupled to an H-mode edge plasma even with the plasma wall distance of about 14 cm. The maximum coupling distance was found to depend on the edge recycling. (author)

Spreading of wave-driven currents in a tokamak

International Nuclear Information System (INIS)

Ignat, D.W.; Kaita, R.; Jardin, S.C.; Okabayashi, M.

1996-01-01

Lower hybrid current drive (LHCD) in the tokamak Princeton Beta Experiment-Modification (PBX-M) is computed with a dynamic model in order to understand an actual discharge aimed at raising the central q above unity. Such configurations offer advantages for steady-state operation and plasma stability. For the particular parameters of this PBX-M experiment, the calculation found singular profiles of plasma current density J and safety factor q developing soon after LHCD begins. Smoothing the lower hybrid-driven current and power using a diffusion-Eke equation and a velocity-independent diffusivity for fast-electron current brought the model into reasonable agreement with the measurements if D fast ∼ 1.0 m 2 /s. Such a value for D fast is in the range suggested by other work

Surface modification of polyacrylonitrile co-polymer membranes using pulsed direct current nitrogen plasma

Energy Technology Data Exchange (ETDEWEB)

Pal, Dipankar; Neogi, Sudarsan; De, Sirshendu, E-mail: sde@che.iitkgp.ernet.in

2015-12-31

Low temperature plasma treatment using pulsed direct current discharge of nitrogen gas was employed to enhance hydrophilicity of the polyacrylonitrile co-polymer membranes. The membranes were characterized in terms of morphology, structure, hydrophilicity, and membrane performance. Properties and functional groups on the surface of polyacrylonitrile co-polymer membranes were investigated by contact angle, scanning electron microscopy, Fourier transform infrared and X-ray photoelectron spectroscopy. Effects of plasma conditions, namely, pulsed voltage, duty cycle and treatment time on increase in membrane hydrophilicity were studied. Permeability of treated membrane was increased by 47% and it was retained up to 70 days. Surface etching due to plasma treatment was confirmed by weight loss of the treated membranes. Due to surface etching, average pore size increased and rejection of 200 kDa polyethylene glycol decreased to about 70% for the treated membrane. Oxygen and nitrogen functional groups were responsible for surface hydrophilicity. - Highlights: • Surface modification of polyacrylonitrile co-polymer membranes by pulsed direct current nitrogen plasma • Hydrophilic functional groups incorporated on the membrane surface • Significant enhancement of the permeability and wettability of the membranes • Water contact angle increased with storage time and finally stabilized.

Surface modification of polyacrylonitrile co-polymer membranes using pulsed direct current nitrogen plasma

International Nuclear Information System (INIS)

Pal, Dipankar; Neogi, Sudarsan; De, Sirshendu

2015-01-01

Low temperature plasma treatment using pulsed direct current discharge of nitrogen gas was employed to enhance hydrophilicity of the polyacrylonitrile co-polymer membranes. The membranes were characterized in terms of morphology, structure, hydrophilicity, and membrane performance. Properties and functional groups on the surface of polyacrylonitrile co-polymer membranes were investigated by contact angle, scanning electron microscopy, Fourier transform infrared and X-ray photoelectron spectroscopy. Effects of plasma conditions, namely, pulsed voltage, duty cycle and treatment time on increase in membrane hydrophilicity were studied. Permeability of treated membrane was increased by 47% and it was retained up to 70 days. Surface etching due to plasma treatment was confirmed by weight loss of the treated membranes. Due to surface etching, average pore size increased and rejection of 200 kDa polyethylene glycol decreased to about 70% for the treated membrane. Oxygen and nitrogen functional groups were responsible for surface hydrophilicity. - Highlights: • Surface modification of polyacrylonitrile co-polymer membranes by pulsed direct current nitrogen plasma • Hydrophilic functional groups incorporated on the membrane surface • Significant enhancement of the permeability and wettability of the membranes • Water contact angle increased with storage time and finally stabilized.

Q-profile evolution and improved core electron confinement in the full current drive operation on Tore Supra

International Nuclear Information System (INIS)

Litaudon, X.; Peysson, Y.; Aniel, T.; Huysmans, G.; Imbeaux, F.; Joffrin, E.; Lasalle, J.; Lotte, Ph.; Schunke, B.; Segui, J.; Tresset, G.; Zabiego, M.

2000-12-01

The formation of a core region with improved electron confinement is reported in the recent full current drive operation of Tore Supra where the plasma current is sustained with the Lower Hybrid, LH, wave. Current profile evolution and thermal electron transport coefficients are directly assessed using the data of the new fast electron Bremsstrahlung tomography that provides the most accurate determination of the LH current and power deposition profiles. The spontaneous rise of the core electron temperature observed a few seconds after the application of the LH power is ascribed to a bifurcation towards a state of reduced electron transport. The role of the magnetic shear is invoked to partly stabilize the anomalous electron turbulence. The electron temperature transition occurs when the q-profile evolves towards a non-inductive state with a non-monotonic shape i.e. when the magnetic shear is reduced close to zero in the plasma core. The improved core confinement phase is often terminated by a sudden MHD activity when the minimum q approaches two. (authors)

Surface modification of TA2 pure titanium by low energy high current pulsed electron beam treatments

International Nuclear Information System (INIS)

Gao Yukui

2011-01-01

Surface integrity changes of TA2 pure titanium including surface topography, microstructure and nanohardness distribution along surface layer were investigated by different techniques of low energy high current pulsed electron beam treatments (LEHCPEBTs). The surface topography was characterized by SEM. Moreover, the TEM observation and X-ray diffraction analysis were performed to reveal the surface modification mechanism of TA2 pure titanium by LEHCPEBTs. The surface roughness was modified by electron beam treatment and the polishing mechanism was analyzed by studying the cross section microstructure of electron beam treated specimens by SEM and TEM. The results show that the surface finish obtains good polishing quality and there is no phase transformation but the dislocations by LEHCPEBT. Furthermore, the nanohardness in the surface modified layer is improved. The remelt and fine-grain microstructure of surface layer caused by LEHCPEBTs are the main polishing mechanism and the reason of modification of surface topography and the increment in nanohardness is mainly due to the dislocations and fine grains in the modified layer induced by LEHCPEBT.

Measurement of lower-hybrid-driven current profile by Abel inversion of electron-cyclotron wave transmission spectra

International Nuclear Information System (INIS)

Fidone, I.; Giruzzi, G.; Caron, X.; Meyer, R.L.

1991-01-01

A method for measuring the radial profile of the lower-hybrid-driven current in a low-density tokamak plasma using electron-cyclotron wave attenuation is discussed. This diagnostic scheme is reminiscent of the transmission interferometry approach, commonly used in tokamaks to measure the plasma density, but now the wave amplitude instead of the phase is measured. Wave attenuation of the ordinary mode at ω p much-lt ω c along vertical chords is measured; at these frequencies, the waves are absorbed by the superthermal tail sustained by lower-hybrid waves and the local wave absorption coefficient is proportional to the noninductive current density. The radial profile of this current is obtained from Abel inversion. An application to the Tore Supra tokamak is presented

Anomalous plasma heating induced by modulation of the current-density profile

International Nuclear Information System (INIS)

Lopes Cardozo, N.J.

1985-05-01

The usual plasma heating in a tokamak needs additional heating to reach ignition temperature (approx. 10 8 K). The method used in the TORTUR III experiment is to induce anomalous plasma resistivity by applying a short (10 microseconds) high-voltage pulse. A sharp rise of the plasma temperature is found almost simultaneously, but this effect, though considerable, is too short-lived to be of interest for a thermonuclear chain reaction. A second pulse gives a second rise of temperature, but this time a slow one, extending over several milliseconds. The mechanism of this delayed heating and the reservoir within the plasma supplying the energy are subjects of investigation in the TORTUR III experiments. Some conclusions concerning the plasma heating mechanism are presented. The conclusion is reached that the application of the high-voltage pulse results in a modulation of the current-density profile: the (normally already peaked) profile sharpens, the current concentrates in the centre of the plasma column. This is a non-equilibrium situation. It relaxes to the noraml current distribution within approximately 2 milliseconds. As long as this relaxation process is not finished, the dissipation is on an enhanced level and anomalous plasma heating is observed. Many plasma parameters are surveyed and evaluated: temperature (both of the ions and the electrons), density, emission spectrum (from microwaves to hard X-rays) and the fluctuation spectrum. Main subject of this report is the measurement and interpretation of the X-rays of the emission spectrum. Experimental results are presented and discussed

Dental modifications: a perspective of Indonesian chronology and the current applications

Directory of Open Access Journals (Sweden)

Rusyad Adi Suriyanto

2010-06-01

Full Text Available Background: Dental modifications are one of the forms of initiation rite. Thus tradition can be found in all of Indonesian regions, even in South East Asia, in previous era. Modes and dentistry, as a culture product, including its modifications or decorations toward body and teeth have appeared in present day, such as tattoo and decorations on teeth which are taken particular model and superimpose or inculcate ornament of jewel, diamond, gold and others. The first research aim is to describe how functions of modifications on teeth represent cultural affinity and population of biologic affinity that accompany it from time to time; starting from prehistoric period to present day, especially in Indonesian region. The second aim is to submit applicable proposal that is useful for medical area, particularly in dentistry. Method: The research materials include teeth of the adult human skulls of Java, Balinese, and East Nusa Tenggara from some paleoanthropological–archaeological sites, as well as isolated permanent dental sample from modern Balinese population. The methods used are visual comparative descriptive method, and browsed through ethnographic and archaeological classic literatures. Result: Chronologically, dental modifications as reference to the pattern of migration and the domination of the culture in the past, and these facts indicate to the biological affinity and indicate to how the culture influences other culture. Conclusion: Some effects of the practices of dental modifications are the emergence of some diseases. Therefore, it is necessary for the agent of health and the traditional practitioner to be aware when they practice the dental modifications. Nevertheless, on the other side, based on explanations the research results, it is clear that dental modifications provide broader knowledge, because it has a very long journey of migration history, occupancy, and culture in this Indonesian Archipelago, which stretches from the period

Generation and characterization of electron bunches with ramped current profiles in a dual-frequency superconducting linear accelerator.

Science.gov (United States)

Piot, P; Behrens, C; Gerth, C; Dohlus, M; Lemery, F; Mihalcea, D; Stoltz, P; Vogt, M

2012-01-20

We report on the successful experimental generation of electron bunches with ramped current profiles. The technique relies on impressing nonlinear correlations in the longitudinal phase space using a superconducing radio frequency linear accelerator operating at two frequencies and a current-enhancing dispersive section. The produced ~700-MeV bunches have peak currents of the order of a kilo-Ampère. Data taken for various accelerator settings demonstrate the versatility of the method and, in particular, its ability to produce current profiles that have a quasilinear dependency on the longitudinal (temporal) coordinate. The measured bunch parameters are shown, via numerical simulations, to produce gigavolt-per-meter peak accelerating electric fields with transformer ratios larger than 2 in dielectric-lined waveguides. © 2012 American Physical Society

Thermal-mechanical simulation of high-current pulsed electron beam surface modification process of pure aluminum

International Nuclear Information System (INIS)

Zou Jianxin; Qin Ying; Wu Aimin; Hao Shengzhi; Wang Xiaogang; Dong Chuang

2004-01-01

A mathematical physics model is established to describe the surface modification process of High Current Pulsed Electron Beams (HCPEB) of pure aluminum alloy. Computer simulation is used to reveal the phenomena of fast heating and cooling, melting, solidification, evaporation, and thermal stress wave associated with the HCPEB bombardment. The calculated melting depth is about 1-10 μm, which is close to the experimental results. The evaporated layer is at nanometer level, which can be omitted in the calculation of temperature field. The thermal stress wave, though as weak as about 0.1 MPa in peak amplitude (proportional to pulsed energy density), has strong impacts on material's structure and properties. (authors)

Profiling of Current Transients in Capacitor Type Diamond Sensors

Science.gov (United States)

Gaubas, Eugenijus; Ceponis, Tomas; Meskauskaite, Dovile; Kazuchits, Nikolai

2015-01-01

The operational characteristics of capacitor-type detectors based on HPHT and CVD diamond have been investigated using perpendicular and parallel injection of carrier domain regimes. Simulations of the drift-diffusion current transients have been implemented by using dynamic models based on Shockley-Ramo’s theorem, under injection of localized surface domains and of bulk charge carriers. The bipolar drift-diffusion regimes have been analyzed for the photo-induced bulk domain (packet) of excess carriers. The surface charge formation and polarization effects dependent on detector biasing voltage have been revealed. The screening effects ascribed to surface charge and to dynamics of extraction of the injected bulk excess carrier domain have been separated and explained. The parameters of drift mobility of the electrons μe = 4000 cm2/Vs and holes μh = 3800 cm2/Vs have been evaluated for CVD diamond using the perpendicular profiling of currents. The coefficient of carrier ambipolar diffusion Da = 97 cm2/s and the carrier recombination lifetime τR,CVD ≌ 110 ns in CVD diamond were extracted by combining analysis of the transients of the sensor current and the microwave probed photoconductivity. The carrier trapping with inherent lifetime τR,HPHT ≌ 2 ns prevails in HPHT diamond. PMID:26061200

Impact of Te and ne on edge current density profiles in ELM mitigated regimes on ASDEX Upgrade

Science.gov (United States)

Dunne, M. G.; Rathgeber, S.; Burckhart, A.; Fischer, R.; Giannone, L.; McCarthy, P. J.; Schneider, P. A.; Wolfrum, E.; the ASDEX Upgrade Team

2015-01-01

ELM resolved edge current density profiles are reconstructed using the CLISTE equilibrium code. As input, highly spatially and temporally resolved edge electron temperature and density profiles are used in addition to data from the extensive set of external poloidal field measurements available at ASDEX Upgrade, flux loop difference measurements, and current measurements in the scrape-off layer. Both the local and flux surface averaged current density profiles are analysed for several ELM mitigation regimes. The focus throughout is on the impact of altered temperature and density profiles on the current density. In particular, many ELM mitigation regimes rely on operation at high density. Two reference plasmas with type-I ELMs are analysed, one with a deuterium gas puff and one without, in order to provide a reference for the behaviour in type-II ELMy regimes and high density ELM mitigation with external magnetic perturbations at ASDEX Upgrade. For type-II ELMs it is found that while a similar pedestal top pressure is sustained at the higher density, the temperature gradient decreases in the pedestal. This results in lower local and flux surface averaged current densities in these phases, which reduces the drive for the peeling mode. No significant differences between the current density measured in the type-I phase and ELM mitigated phase is seen when external perturbations are applied, though the pedestal top density was increased. Finally, ELMs during the nitrogen seeded phase of a high performance discharge are analysed and compared to ELMs in the reference phase. An increased pedestal pressure gradient, which is the source of confinement improvement in impurity seeded discharges, causes a local current density increase. However, the increased Zeff in the pedestal acts to reduce the flux surface averaged current density. This dichotomy, which is not observed in other mitigation regimes, could act to stabilize both the ballooning mode and the peeling mode at the

Ballooning mode stability for self-consistent pressure and current profiles at the H-mode edge

International Nuclear Information System (INIS)

Miller, R.L.; Lin-Liu, Y.R.; Osborne, T.H.; Taylor, T.S.

1997-11-01

The edge pressure gradient (H-mode pedestal) for computed equilibria in which the current density profile is consistent with the bootstrap current may not be limited by the first regime ballooning limit. The transition to second stability is easier for: higher elongation, intermediate triangularity, larger ratio, pedestal at larger radius, narrower pedestal width, higher q 95 , and lower collisionality

Microarray-based analysis of plasma cirDNA epigenetic modification profiling in xenografted mice exposed to intermittent hypoxia

Directory of Open Access Journals (Sweden)

Rene Cortese

2015-09-01

Full Text Available Intermittent hypoxia (IH during sleep is one of the major abnormalities occurring in patients suffering from obstructive sleep apnea (OSA, a highly prevalent disorder affecting 6–15% of the general population, particularly among obese people. IH has been proposed as a major determinant of oncogenetically-related processes such as tumor growth, invasion and metastasis. During the growth and expansion of tumors, fragmented DNA is released into the bloodstream and enters the circulation. Circulating tumor DNA (cirDNA conserves the genetic and epigenetic profiles from the tumor of origin and can be isolated from the plasma fraction. Here we report a microarray-based epigenetic profiling of cirDNA isolated from blood samples of mice engrafted with TC1 epithelial lung cancer cells and controls, which were exposed to IH during sleep (XenoIH group, n = 3 or control conditions, (i.e., room air (RA; XenoRA group, n = 3 conditions. To prepare the targets for microarray hybridization, we applied a previously developed method that enriches the modified fraction of the cirDNA without amplification of genomic DNA. Regions of differential cirDNA modification between the two groups were identified by hybridizing the enriched fractions for each sample to Affymetrix GeneChip Human Promoter Arrays 1.0R. Microarray raw and processed data were deposited in NCBI's Gene Expression Omnibus (GEO database (accession number: GSE61070.

Highly Sensitive and High-Throughput Analysis of Plant Hormones Using MS-Probe Modification and Liquid Chromatography–Tandem Mass Spectrometry: An Application for Hormone Profiling in Oryza sativa

Science.gov (United States)

Kojima, Mikiko; Kamada-Nobusada, Tomoe; Komatsu, Hirokazu; Takei, Kentaro; Kuroha, Takeshi; Mizutani, Masaharu; Ashikari, Motoyuki; Ueguchi-Tanaka, Miyako; Matsuoka, Makoto; Suzuki, Koji; Sakakibara, Hitoshi

2009-01-01

We have developed a highly sensitive and high-throughput method for the simultaneous analysis of 43 molecular species of cytokinins, auxins, ABA and gibberellins. This method consists of an automatic liquid handling system for solid phase extraction and ultra-performance liquid chromatography (UPLC) coupled with a tandem quadrupole mass spectrometer (qMS/MS) equipped with an electrospray interface (ESI; UPLC-ESI-qMS/MS). In order to improve the detection limit of negatively charged compounds, such as gibberellins, we chemically derivatized fractions containing auxin, ABA and gibberellins with bromocholine that has a quaternary ammonium functional group. This modification, that we call ‘MS-probe’, makes these hormone derivatives have a positive ion charge and permits all compounds to be measured in the positive ion mode with UPLC-ESI-qMS/MS in a single run. Consequently, quantification limits of gibberellins increased up to 50-fold. Our current method needs 180 plant samples simultaneously. Application of this method to plant hormone profiling enabled us to draw organ distribution maps of hormone species in rice and also to identify interactions among the four major hormones in the rice gibberellin signaling mutants, gid1-3, gid2-1 and slr1. Combining the results of hormone profiling data with transcriptome data in the gibberellin signaling mutants allows us to analyze relationships between changes in gene expression and hormone metabolism. PMID:19369275

Modification of Sunlight Radiation through Colored Photo-Selective Nets Affects Anthocyanin Profile in Vaccinium spp. Berries.

Science.gov (United States)

Zoratti, Laura; Jaakola, Laura; Häggman, Hely; Giongo, Lara

2015-01-01

In recent years, the interest on the effects of the specific wavelengths of the light spectrum on growth and metabolism of plants has been increasing markedly. The present study covers the effect of modified sunlight conditions on the accumulation of anthocyanin pigments in two Vaccinium species: the European wild bilberry (V. myrtillus L.) and the cultivated highbush blueberry (V. corymbosum L.). The two Vaccinium species were grown in the same test field in the Alps of Trentino (Northern Italy) under modified light environment. The modification of sunlight radiation was carried out in field, through the use of colored photo-selective nets throughout the berry ripening during two consecutive growing seasons. The anthocyanin profile was then assessed in berries at ripeness. The results indicated that the light responses of the two Vaccinium species studied were different. Although both studied species are shade-adapted plants, 90% shading of sunlight radiation was beneficial only for bilberry plants, which accumulated the highest content of anthocyanins in both seasons. The same condition, instead, was not favorable for blueberries, whose maturation was delayed for at least two weeks, and anthocyanin accumulation was significantly decreased compared to berries grown under sunlight conditions. Moreover, the growing season had strong influence on the anthocyanin accumulation in both species, in relation to temperature flow and sunlight spectra composition during the berry ripening period. Our results suggest that the use of colored photo-selective nets may be a complementary agricultural practice for cultivation of Vaccinium species. However, further studies are needed to analyze the effect of the light spectra modifications to other nutritional properties, and to elucidate the molecular mechanisms behind the detected differences between the two relative Vaccinium species.

Extraction Analysis and Creation of Three-Dimensional Road Profiles Using Matlab OpenCRG Tool

Directory of Open Access Journals (Sweden)

Rakesh Hari Borse

2015-08-01

Full Text Available In vehicle systems dynamics there are wide applications of simulation of vehicles on road surfaces. These simulation applications are related to vehicle handling ride comfort and durability. For accurate prediction of results there is a need for a reliable and efficient road representations. The efficient representation of road surface profiles is to represent them in three-dimensional space. This is made possible by the CRG Curved Regular Grid approach. OpenCRG is a completely open source project including a tool suite for the creation modification and evaluation of road surfaces. Its objective is to standardized detailed road surface description and it may be used for applications like tire models vibrations or driving simulation. The Matlab tool suite of OpenCRG provides powerful modification or creation tools and allows to visualize the 3D road data representation. The current research focuses on basic concepts of OpenCRG and its Matlab environment. The extraction of longitudinal two-dimensional road profiles from three-dimensional CRG format is researched. The creation of simple virtual three-dimensional roads has been programmed. A Matlab software tool to extract create and analyze the three-dimensional road profiles is to be developed.

Current meter and temperature profile data from moored current meter casts in the TOGA area - Atlantic Ocean from 10 September 1970 - 27 October 1980 (NODC Accession 8600320)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Current meter and temperature profile data were collected using moored current meter - PCM casts in the TOGA area - Atlantic Ocean from September 10, 1970 to October...

Improving sensitivity of residual current transformers to high frequency earth fault currents

Directory of Open Access Journals (Sweden)

Czapp Stanislaw

2017-09-01

Full Text Available For protection against electric shock in low voltage systems residual current devices are commonly used. However, their proper operation can be interfered when high frequency earth fault current occurs. Serious hazard of electrocution exists then. In order to detect such a current, it is necessary to modify parameters of residual current devices, especially the operating point of their current transformer. The authors proposed the modification in the structure of residual current devices. This modification improves sensitivity of residual current devices when high frequency earth fault current occurs. The test of the modified residual current device proved that the authors’ proposition is appropriate.

Improvised explosive devices: pathophysiology, injury profiles and current medical management.

Science.gov (United States)

Ramasamy, A; Hill, A M; Clasper, J C

2009-12-01

The improvised explosive device (IED), in all its forms, has become the most significant threat to troops operating in Afghanistan and Iraq. These devices range from rudimentary home made explosives to sophisticated weapon systems containing high-grade explosives. Within this broad definition they may be classified as roadside explosives and blast mines, explosive formed pojectile (EFP) devices and suicide bombings. Each of these groups causeinjury through a number of different mechanisms and can result in vastly different injury profiles. The "Global War on Terror" has meant that incidents which were previously exclusively seen in conflict areas, can occur anywhere, and clinicians who are involved in emergency trauma care may be required to manage casualties from similar terrorist attacks. An understanding of the types of devices and their pathophysiological effects is necessary to allow proper planning of mass casualty events and to allow appropriate management of the complex poly-trauma casualties they invariably cause. The aim of this review article is to firstly describe the physics and injury profile from these different devices and secondly to present the current clinical evidence that underpins their medical management.

A Review of Additive Mixed-Electric Discharge Machining: Current Status and Future Perspectives for Surface Modification of Biomedical Implants

Directory of Open Access Journals (Sweden)

Abdul’Azeez Abdu Aliyu

2017-01-01

Full Text Available Surface treatment remained a key solution to numerous problems of synthetic hard tissues. The basic methods of implant surface modification include various physical and chemical deposition techniques. However, most of these techniques have several drawbacks such as excessive cost and surface cracks and require very high sintering temperature. Additive mixed-electric discharge machining (AM-EDM is an emerging technology which simultaneously acts as a machining and surface modification technique. Aside from the mere molds, dies, and tool fabrication, AM-EDM is materializing to finishing of automobiles and aerospace, nuclear, and biomedical components, through the concept of material migrations. The mechanism of material transfer by AM-EDM resembles electrophoretic deposition, whereby the additives in the AM-EDM dielectric fluids are melted and migrate to the machined surface, forming a mirror-like finishing characterized by extremely hard, nanostructured, and nanoporous layers. These layers promote the bone in-growth and strengthen the cell adhesion. Implant shaping and surface treatment through AM-EDM are becoming a key research focus in recent years. This paper reports and summarizes the current advancement of AM-EDM as a potential tool for orthopedic and dental implant fabrication. Towards the end of this paper, the current challenges and future research trends are highlighted.

HMCan-diff: a method to detect changes in histone modifications in cells with different genetic characteristics

KAUST Repository

Ashoor, Haitham; Louis-Brennetot, Caroline; Janoueix-Lerosey, Isabelle; Bajic, Vladimir B.; Boeva, Valentina

2016-01-01

Comparing histone modification profiles between cancer and normal states, or across different tumor samples, can provide insights into understanding cancer initiation, progression and response to therapy. ChIP-seq histone modification data of cancer

Radial profiles of hard X-ray emission during steady state current drive in the TRIAM-1M tokamak

International Nuclear Information System (INIS)

Nakamura, Y.; Takabatake, Y.; Jotaki, E.; Moriyama, S.; Nagao, A.; Nakamura, K.; Hiraki, N.; Itoh, S.

1990-01-01

The hard X-ray emission from the TRIAM-1M tokamak plasma during steady state lower hybrid current drive with a discharge duration of a few minutes was measured with sodium iodide scintillation spectrometers. The radial profiles of the X-ray emission were also measured and indicate that, in the low density regime (n e =(1-3)x10 12 cm -3 ), the current carrying high energy electrons are mainly in the inner region of the plasma column and their radial profile remains unchanged during current drive. On the other hand, high density discharges (n e =(3-6)x10 12 cm -3 ) are always accompanied by an abrupt drop of the plasma current, and the X-ray emission profile changes from peaked to broad. This change can be attributed to the conditions of wave accessibility. As the electron density increases, the accessibility of the plasma to lower hybrid waves with low values of the parallel wave number n parallel is significantly reduced and high energy electrons resonating with the waves are produced at the plasma periphery. Interaction of these electrons with the limiters causes an increase of the electron density in this region; waves with low n parallel then become completely excluded from the inner part of the plasma column. This interpretation is supported by measurements of the density profile and impurity radiation, and has been confirmed in an investigation of discharges with additional gas puffing. (author). 17 refs, 21 figs

Power deposition profile during lower hybrid current drive in Tore Supra

International Nuclear Information System (INIS)

Pecquet, A.L.; Moreau, D.; Fall, T.; Lasalle, J.; Lecoustey, P.; Mattioli, M.; Peysson, Y.; Auge, N.; Rodriguez, L.; Talvard, M.; Hubbard, A.; Moret, J.M.

1991-01-01

Lower hybrid current drive (LHCD) experiments have been performed in Tore Supra in various density regimes. The total power coupled to the plasma reached 4MW and a strong electron heating has been observed. To investigate the power deposition mechanism on the electrons, r.f power modulation experiments have been performed. These experiments allow us to estimate the power deposition profiles on both thermal and non-thermal electrons and also to study their respective time responses. From these studies it is possible to deduce a thermal heating scenario which agrees with the experimental results

Direct Profiling the Post-Translational Modification Codes of a Single Protein Immobilized on a Surface Using Cu-free Click Chemistry.

Science.gov (United States)

Kim, Kyung Lock; Park, Kyeng Min; Murray, James; Kim, Kimoon; Ryu, Sung Ho

2018-05-23

Combinatorial post-translational modifications (PTMs), which can serve as dynamic "molecular barcodes", have been proposed to regulate distinct protein functions. However, studies of combinatorial PTMs on single protein molecules have been hindered by a lack of suitable analytical methods. Here, we describe erasable single-molecule blotting (eSiMBlot) for combinatorial PTM profiling. This assay is performed in a highly multiplexed manner and leverages the benefits of covalent protein immobilization, cyclic probing with different antibodies, and single molecule fluorescence imaging. Especially, facile and efficient covalent immobilization on a surface using Cu-free click chemistry permits multiple rounds (>10) of antibody erasing/reprobing without loss of antigenicity. Moreover, cumulative detection of coregistered multiple data sets for immobilized single-epitope molecules, such as HA peptide, can be used to increase the antibody detection rate. Finally, eSiMBlot enables direct visualization and quantitative profiling of combinatorial PTM codes at the single-molecule level, as we demonstrate by revealing the novel phospho-codes of ligand-induced epidermal growth factor receptor. Thus, eSiMBlot provides an unprecedentedly simple, rapid, and versatile platform for analyzing the vast number of combinatorial PTMs in biological pathways.

Chimira: analysis of small RNA sequencing data and microRNA modifications.

Science.gov (United States)

Vitsios, Dimitrios M; Enright, Anton J

2015-10-15

Chimira is a web-based system for microRNA (miRNA) analysis from small RNA-Seq data. Sequences are automatically cleaned, trimmed, size selected and mapped directly to miRNA hairpin sequences. This generates count-based miRNA expression data for subsequent statistical analysis. Moreover, it is capable of identifying epi-transcriptomic modifications in the input sequences. Supported modification types include multiple types of 3'-modifications (e.g. uridylation, adenylation), 5'-modifications and also internal modifications or variation (ADAR editing or single nucleotide polymorphisms). Besides cleaning and mapping of input sequences to miRNAs, Chimira provides a simple and intuitive set of tools for the analysis and interpretation of the results (see also Supplementary Material). These allow the visual study of the differential expression between two specific samples or sets of samples, the identification of the most highly expressed miRNAs within sample pairs (or sets of samples) and also the projection of the modification profile for specific miRNAs across all samples. Other tools have already been published in the past for various types of small RNA-Seq analysis, such as UEA workbench, seqBuster, MAGI, OASIS and CAP-miRSeq, CPSS for modifications identification. A comprehensive comparison of Chimira with each of these tools is provided in the Supplementary Material. Chimira outperforms all of these tools in total execution speed and aims to facilitate simple, fast and reliable analysis of small RNA-Seq data allowing also, for the first time, identification of global microRNA modification profiles in a simple intuitive interface. Chimira has been developed as a web application and it is accessible here: http://www.ebi.ac.uk/research/enright/software/chimira. aje@ebi.ac.uk Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press.

CoverageAnalyzer (CAn: A Tool for Inspection of Modification Signatures in RNA Sequencing Profiles

Directory of Open Access Journals (Sweden)

Ralf Hauenschild

2016-11-01

Full Text Available Combination of reverse transcription (RT and deep sequencing has emerged as a powerful instrument for the detection of RNA modifications, a field that has seen a recent surge in activity because of its importance in gene regulation. Recent studies yielded high-resolution RT signatures of modified ribonucleotides relying on both sequence-dependent mismatch patterns and reverse transcription arrests. Common alignment viewers lack specialized functionality, such as filtering, tailored visualization, image export and differential analysis. Consequently, the community will profit from a platform seamlessly connecting detailed visual inspection of RT signatures and automated screening for modification candidates. CoverageAnalyzer (CAn was developed in response to the demand for a powerful inspection tool. It is freely available for all three main operating systems. With SAM file format as standard input, CAn is an intuitive and user-friendly tool that is generally applicable to the large community of biomedical users, starting from simple visualization of RNA sequencing (RNA-Seq data, up to sophisticated modification analysis with significance-based modification candidate calling.

Y-12 Industrial Landfill V. Permit application modifications

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

This report contains the modifications in operations and design to meet the Tennessee Department of Environment and Conversation (TDEC) July 10, 1993, amendments to the regulations for Class 2 landfills. These modifications, though extensive in design and construction cost, are considered minor revisions and should not require a processing fee. Area 1 of ILF V, comprising approximately 20% of the ILF V footprint, was designed and submitted to TDEC prior to the implementation of current regulations. This initial area was constructed with a compacted clay liner and leachate collection system, and became operational in April 1994. The current regulations require landfills to have a composite liner with leachate collection system and closure cap. Modifications to upgrade Areas 2 and 3 of ILF V to meet the current TDEC requirements are included.

Y-12 Industrial Landfill V. Permit application modifications

International Nuclear Information System (INIS)

1995-09-01

This report contains the modifications in operations and design to meet the Tennessee Department of Environment and Conversation (TDEC) July 10, 1993, amendments to the regulations for Class 2 landfills. These modifications, though extensive in design and construction cost, are considered minor revisions and should not require a processing fee. Area 1 of ILF V, comprising approximately 20% of the ILF V footprint, was designed and submitted to TDEC prior to the implementation of current regulations. This initial area was constructed with a compacted clay liner and leachate collection system, and became operational in April 1994. The current regulations require landfills to have a composite liner with leachate collection system and closure cap. Modifications to upgrade Areas 2 and 3 of ILF V to meet the current TDEC requirements are included

Modification of Sunlight Radiation through Colored Photo-Selective Nets Affects Anthocyanin Profile in Vaccinium spp. Berries.

Directory of Open Access Journals (Sweden)

Laura Zoratti

Full Text Available In recent years, the interest on the effects of the specific wavelengths of the light spectrum on growth and metabolism of plants has been increasing markedly. The present study covers the effect of modified sunlight conditions on the accumulation of anthocyanin pigments in two Vaccinium species: the European wild bilberry (V. myrtillus L. and the cultivated highbush blueberry (V. corymbosum L..The two Vaccinium species were grown in the same test field in the Alps of Trentino (Northern Italy under modified light environment. The modification of sunlight radiation was carried out in field, through the use of colored photo-selective nets throughout the berry ripening during two consecutive growing seasons. The anthocyanin profile was then assessed in berries at ripeness.The results indicated that the light responses of the two Vaccinium species studied were different. Although both studied species are shade-adapted plants, 90% shading of sunlight radiation was beneficial only for bilberry plants, which accumulated the highest content of anthocyanins in both seasons. The same condition, instead, was not favorable for blueberries, whose maturation was delayed for at least two weeks, and anthocyanin accumulation was significantly decreased compared to berries grown under sunlight conditions. Moreover, the growing season had strong influence on the anthocyanin accumulation in both species, in relation to temperature flow and sunlight spectra composition during the berry ripening period.Our results suggest that the use of colored photo-selective nets may be a complementary agricultural practice for cultivation of Vaccinium species. However, further studies are needed to analyze the effect of the light spectra modifications to other nutritional properties, and to elucidate the molecular mechanisms behind the detected differences between the two relative Vaccinium species.

Continuous measurements of discharge from a horizontal acoustic Doppler current profiler in a tidal river

NARCIS (Netherlands)

Hoitink, A.J.F.; Buschman, F.A.; Vermeulen, B.

2009-01-01

Acoustic Doppler current profilers (ADCPs) can be mounted horizontally at a river bank, yielding single-depth horizontal array observations of velocity across the river. This paper presents a semideterministic, semistochastic method to obtain continuous measurements of discharge from horizontal ADCP

Measurement of neoclassically predicted edge current density at ASDEX Upgrade

Science.gov (United States)

Dunne, M. G.; McCarthy, P. J.; Wolfrum, E.; Fischer, R.; Giannone, L.; Burckhart, A.; the ASDEX Upgrade Team

2012-12-01

Experimental confirmation of neoclassically predicted edge current density in an ELMy H-mode plasma is presented. Current density analysis using the CLISTE equilibrium code is outlined and the rationale for accuracy of the reconstructions is explained. Sample profiles and time traces from analysis of data at ASDEX Upgrade are presented. A high time resolution is possible due to the use of an ELM-synchronization technique. Additionally, the flux-surface-averaged current density is calculated using a neoclassical approach. Results from these two separate methods are then compared and are found to validate the theoretical formula. Finally, several discharges are compared as part of a fuelling study, showing that the size and width of the edge current density peak at the low-field side can be explained by the electron density and temperature drives and their respective collisionality modifications.

Measurement of neoclassically predicted edge current density at ASDEX Upgrade

International Nuclear Information System (INIS)

Dunne, M.G.; McCarthy, P.J.; Wolfrum, E.; Fischer, R.; Giannone, L.; Burckhart, A.

2012-01-01

Experimental confirmation of neoclassically predicted edge current density in an ELMy H-mode plasma is presented. Current density analysis using the CLISTE equilibrium code is outlined and the rationale for accuracy of the reconstructions is explained. Sample profiles and time traces from analysis of data at ASDEX Upgrade are presented. A high time resolution is possible due to the use of an ELM-synchronization technique. Additionally, the flux-surface-averaged current density is calculated using a neoclassical approach. Results from these two separate methods are then compared and are found to validate the theoretical formula. Finally, several discharges are compared as part of a fuelling study, showing that the size and width of the edge current density peak at the low-field side can be explained by the electron density and temperature drives and their respective collisionality modifications. (paper)

Fabrication and Modification of Nanoporous Silicon Particles

Science.gov (United States)

Ferrari, Mauro; Liu, Xuewu

2010-01-01

Silicon-based nanoporous particles as biodegradable drug carriers are advantageous in permeation, controlled release, and targeting. The use of biodegradable nanoporous silicon and silicon dioxide, with proper surface treatments, allows sustained drug release within the target site over a period of days, or even weeks, due to selective surface coating. A variety of surface treatment protocols are available for silicon-based particles to be stabilized, functionalized, or modified as required. Coated polyethylene glycol (PEG) chains showed the effective depression of both plasma protein adsorption and cell attachment to the modified surfaces, as well as the advantage of long circulating. Porous silicon particles are micromachined by lithography. Compared to the synthesis route of the nanomaterials, the advantages include: (1) the capability to make different shapes, not only spherical particles but also square, rectangular, or ellipse cross sections, etc.; (2) the capability for very precise dimension control; (3) the capacity for porosity and pore profile control; and (4) allowance of complex surface modification. The particle patterns as small as 60 nm can be fabricated using the state-of-the-art photolithography. The pores in silicon can be fabricated by exposing the silicon in an HF/ethanol solution and then subjecting the pores to an electrical current. The size and shape of the pores inside silicon can be adjusted by the doping of the silicon, electrical current application, the composition of the electrolyte solution, and etching time. The surface of the silicon particles can be modified by many means to provide targeted delivery and on-site permanence for extended release. Multiple active agents can be co-loaded into the particles. Because the surface modification of particles can be done on wafers before the mechanical release, asymmetrical surface modification is feasible. Starting from silicon wafers, a treatment, such as KOH dipping or reactive ion

Risk-profile modification of energy projects

International Nuclear Information System (INIS)

Larson, B.O.

1992-01-01

The commodity futures and swaps markets are thought to be the invention of speculators, the bane of the oil business, or possibly something confined to finance departments of major corporations. In actuality, they should be considered more as an insurance vehicle and can be used at the project level to modify the risk profile of a property. In this context, an increased familiarity with them can be useful for an engineer. Either futures of swaps can be used to guarantee or modify product prices. While this does not necessarily maximize cash flow or present worth, it can protect a project or company for several years from downside price risk, thereby reducing the risk of the venture. This can be particularly important if lower product prices would cause unacceptable cash flows or net incomes. This paper reports that reducing risk by limiting downside price exposure could alter budgeting decisions, allow continued or expanded operations of a particular property, or increase debt capacity

Alterations in Aspergillus brasiliensis (niger) ATCC 9642 membranes associated to metabolism modifications during application of low-intensity electric current.

Science.gov (United States)

Velasco-Alvarez, Nancy; Gutiérrez-Rojas, Mariano; González, Ignacio

2017-12-01

The effects of electric current on membranes associated with metabolism modifications in Aspergillus brasiliensis (niger) ATCC 9642 were studied. A 450-mL electrochemical cell with titanium ruthenium-oxide coated electrodes and packed with 15g of perlite, as inert support, was inoculated with A. brasiliensis spores and incubated in a solid inert-substrate culture (12 d; 30°C). Then, 4.5days after starting the culture, a current of 0.42mAcm -2 was applied for 24h. The application of low-intensity electric current increased the molecular oxygen consumption rate in the mitochondrial respiratory chain, resulting in high concentrations of reactive oxygen species, promoting high lipoperoxidation levels, according to measured malondialdehyde, and consequent alterations in membrane permeability explained the high n-hexadecane (HXD) degradation rates observed here (4.7-fold higher than cultures without current). Finally, cell differentiation and spore production were strongly stimulated. The study contributes to the understanding of the effect of current on the cell membrane and its association with HXD metabolism. Copyright © 2017. Published by Elsevier B.V.

Applications of Bayesian temperature profile reconstruction to automated comparison with heat transport models and uncertainty quantification of current diffusion

International Nuclear Information System (INIS)

Irishkin, M.; Imbeaux, F.; Aniel, T.; Artaud, J.F.

2015-01-01

Highlights: • We developed a method for automated comparison of experimental data with models. • A unique platform implements Bayesian analysis and integrated modelling tools. • The method is tokamak-generic and is applied to Tore Supra and JET pulses. • Validation of a heat transport model is carried out. • We quantified the uncertainties due to Te profiles in current diffusion simulations. - Abstract: In the context of present and future long pulse tokamak experiments yielding a growing size of measured data per pulse, automating data consistency analysis and comparisons of measurements with models is a critical matter. To address these issues, the present work describes an expert system that carries out in an integrated and fully automated way (i) a reconstruction of plasma profiles from the measurements, using Bayesian analysis (ii) a prediction of the reconstructed quantities, according to some models and (iii) a comparison of the first two steps. The first application shown is devoted to the development of an automated comparison method between the experimental plasma profiles reconstructed using Bayesian methods and time dependent solutions of the transport equations. The method was applied to model validation of a simple heat transport model with three radial shape options. It has been tested on a database of 21 Tore Supra and 14 JET shots. The second application aims at quantifying uncertainties due to the electron temperature profile in current diffusion simulations. A systematic reconstruction of the Ne, Te, Ti profiles was first carried out for all time slices of the pulse. The Bayesian 95% highest probability intervals on the Te profile reconstruction were then used for (i) data consistency check of the flux consumption and (ii) defining a confidence interval for the current profile simulation. The method has been applied to one Tore Supra pulse and one JET pulse.

The ability of current micro-velocity models to represent center-limb line profiles

International Nuclear Information System (INIS)

Evans, J.C.; Testerman, L.

1975-01-01

Results are presented on the ability of microturbulences, LTE line formation and a homogeneous thermal model to realistically represent the center-limb variation of temporally and spacially averaged solar line profiles. Three somewhat similar semi-empirical thermal models have been used in combination with five current microturbulence models which cover the gamut of homogeneous-isotropic to nonhomogeneous-anisotropic. From high resolution photoelectric data for (lambdalambda 5000-6000 at five μ-values(1,0.63,0.4,0.25,0.16) obtained at KPNO, were selected 17 Fe I and 5 Fe II line profiles to be unblended and symmetrized for study. An iterative scheme has been developed to calculate theoretical profiles for the various combination of models and compare them to the observed profile using the abundance at each limb position and the magnitude of the pressure broadening at the center of the disc as parameters. It was found that a microturbulence model, for which the radial and tangential components increase into deeper layers with xisub(tan)>xisub(rad), produces a reasonable good center-limb fit for lines less than 100mA. However for lines stronger than 140mA, microturbulence models with no depth dependence produce the best match between theory and observation. Thus there is reason to question the uniqueness of the microturbulence concept. (Auth.)

Subthreshold Current and Swing Modeling of Gate Underlap DG MOSFETs with a Source/Drain Lateral Gaussian Doping Profile

Science.gov (United States)

Singh, Kunal; Kumar, Sanjay; Goel, Ekta; Singh, Balraj; Kumar, Mirgender; Dubey, Sarvesh; Jit, Satyabrata

2017-01-01

This paper proposes a new model for the subthreshold current and swing of the short-channel symmetric underlap ultrathin double gate metal oxide field effect transistors with a source/drain lateral Gaussian doping profile. The channel potential model already reported earlier has been utilized to formulate the closed form expression for the subthreshold current and swing of the device. The effects of the lateral straggle and geometrical parameters such as the channel length, channel thickness, and oxide thickness on the off current and subthreshold slope have been demonstrated. The devices with source/drain lateral Gaussian doping profiles in the underlap structure are observed to be highly resistant to short channel effects while improving the current drive. The proposed model is validated by comparing the results with the numerical simulation data obtained by using the commercially available ATLAS™, a two-dimensional (2-D) device simulator from SILVACO.

Plasma current profile during current reversal in a tokamak

International Nuclear Information System (INIS)

Huang Jianguo; Yang Xuanzong; Zheng Shaobai; Feng Chunhua; Zhang Houxian; Wang Long

1999-01-01

Alternating current operation with one full cycle and a current level of 2.5 kA have been achieved in the CT-6B tokamak. The poloidal magnetic field in the plasma is measured with two internal magnetic probes in repeated discharges. The current distribution is reconstructed with an inversion algorithm. The inverse current first appears on the weak field side. The existence of magnetic surfaces and rotational transform provide particle confinement in the current reversal phase

Application of the inverse estimation method of current distribution from magnetic fields using genetic algorithm to beam profile measurement

International Nuclear Information System (INIS)

Kishimoto, M.; Sakasai, K.; Ara, K.

1994-01-01

In this paper, the new type of non-invasive beam profile monitor for intense ion accelerator using high-temperature superconductor. We regard the inverse estimation problem of beam profile as the optimum allocation problem of the currents into the cross-section of the beam vacuum pipe and applied genetic algorithm to solve this optimization problem. And we carried out the computer simulation to verify the effectiveness of this inverse estimation method of beam profile. (author)

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

Energy Technology Data Exchange (ETDEWEB)

Parke, E. [Department of Physics and Astronomy, University of California Los Angeles 475 Portola Plaza, Los Angeles, California 90095 (United States); Department of Physics, University of Wisconsin-Madison 1150 University Ave., Madison, Wisconsin 53706 (United States); Anderson, J. K.; Den Hartog, D. J. [Department of Physics, University of Wisconsin-Madison 1150 University Ave., Madison, Wisconsin 53706 (United States); Brower, D. L.; Ding, W. X.; Lin, L. [Department of Physics and Astronomy, University of California Los Angeles 475 Portola Plaza, Los Angeles, California 90095 (United States); Johnson, C. A. [Department of Physics, University of Wisconsin-Madison 1150 University Ave., Madison, Wisconsin 53706 (United States); Department of Physics, Auburn University 206 Allison Laboratory, Auburn, Alabama 36849 (United States)

2016-05-15

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

Differential profiles of direct and indirect modification of vector feeding behaviour by a plant virus.

Science.gov (United States)

He, Wen-Bo; Li, Jie; Liu, Shu-Sheng

2015-01-08

Plant viruses interact with their insect vectors directly and indirectly via host plants, and this tripartite interaction may produce fitness benefits to both the vectors and the viruses. Our previous studies show that the Middle East-Asia Minor 1 (MEAM1) species of the whitefly Bemisia tabaci complex improved its performance on tobacco plants infected by the Tomato yellow leaf curl China virus (TYLCCNV), which it transmits, although virus infection of the whitefly per se reduced its performance. Here, we use electrical penetration graph recording to investigate the direct and indirect effects of TYLCCNV on the feeding behaviour of MEAM1. When feeding on either cotton, a non-host of TYLCCNV, or uninfected tobacco, a host of TYLCCNV, virus-infection of the whiteflies impeded their feeding. Interestingly, when viruliferous whiteflies fed on virus-infected tobacco, their feeding activities were no longer negatively affected; instead, the virus promoted whitefly behaviour related to rapid and effective sap ingestion. Our findings show differential profiles of direct and indirect modification of vector feeding behaviour by a plant virus, and help to unravel the behavioural mechanisms underlying a mutualistic relationship between an insect vector and a plant virus that also has features reminiscent of an insect pathogen.

Isotope-beam modification of materials at eV energies

International Nuclear Information System (INIS)

Krug, C.; Radtke, C.; Stedile, F.C.; Baumvol, I.J.R.

2001-01-01

We developed a low energy ion beam deposition system for isotope-selective modification of materials. It consists of a conventional ion implanter (HVEE 500 kV) and an attachable deceleration system. 29 (N 2 ) + ion beams were used for the nitridation of Si(0 0 1) and the resulting 15 N retained doses and profiles were determined by narrow nuclear resonance profiling. 29 Si was deposited on amorphous carbon films on Si(0 0 1) and the doses evaluated by channeled α particle beams with detection of scattered α at grazing angles. 29 Si was also deposited on Si(0 0 1) and the resulting profiles determined by narrow nuclear resonance

Water vapour and ozone profiles in the midlatitude upper troposphere

Directory of Open Access Journals (Sweden)

G. Vaughan

2005-01-01

Full Text Available We present an investigation of upper tropospheric humidity profiles measured with a standard radiosonde, the Vaisala RS80-A, and a commercial frost-point hygrometer, the Snow White. Modifications to the Snow White, to enable the mirror reflectivity and Peltier cooling current to be monitored during flight, were found to be necessary to determine when the instrument was functioning correctly; a further modification to prevent hydrometeors entering the inlet was also implemented. From 23 combined flights of an ozonesonde, radiosonde and Snow White between September 2001 and July 2002, clear agreement was found between the two humidity sensors, with a mean difference of <2% in relative humidity from 2 to 10km, and 2.2% between 10 and 13km. This agreement required a correction to the radiosonde humidity, as described by Miloshevich et al. (2001. Using this result, the dataset of 324 ozonesonde/RS80-A profiles measured from Aberystwyth between 1991 and 2002 was examined to derive statistics for the distribution of water vapour and ozone. Supersaturation with respect to ice was frequently seen at the higher levels - 24% of the time in winter between 8 and 10km. The fairly uniform distribution of relative humidity persisted to 120% in winter, but decreased rapidly above 100% in summer.

Risk profile modification of energy projects

International Nuclear Information System (INIS)

Larson, B.O.

1992-01-01

The commodity futures and swaps markets are thought by some to be the invention of speculators, the bane of the oil business, or possibly something confined to finance departments of major corporations. In actuality, they should be considered more as insurance and can be utilized at the project level to modify the risk profile of a property. In this context, an increased familiarity with them can be useful for an engineer. This paper reports that either futures or swaps can be used to guarantee or modify product prices, an accomplishment very difficult or impossible to duplicate through other means, particularly with such integrity. Participation in futures or swaps does not necessarily maximize cashflow or present worth, it can either guarantee the price, put a minimum price in place or offer a combination of the above. A project or company can be protected for several years from downside price risk using swaps. Not being subject to market price swings substantially reduces the risk of the venture. This can be particularly important if lower product prices would cause unacceptable cashflows or net incomes

Methodological guidelines for developing accident modification functions

DEFF Research Database (Denmark)

Elvik, Rune

2015-01-01

This paper proposes methodological guidelines for developing accident modification functions. An accident modification function is a mathematical function describing systematic variation in the effects of road safety measures. The paper describes ten guidelines. An example is given of how to use...... limitations in developing accident modification functions are the small number of good evaluation studies and the often huge variation in estimates of effect. It is therefore still not possible to develop accident modification functions for very many road safety measures. © 2015 Elsevier Ltd. All rights...... the guidelines. The importance of exploratory analysis and an iterative approach in developing accident modification functions is stressed. The example shows that strict compliance with all the guidelines may be difficult, but represents a level of stringency that should be strived for. Currently the main...

Visualizing flow fields using acoustic Doppler current profilers and the Velocity Mapping Toolbox

Science.gov (United States)

Jackson, P. Ryan

2013-01-01

The purpose of this fact sheet is to provide examples of how the U.S. Geological Survey is using acoustic Doppler current profilers for much more than routine discharge measurements. These instruments are capable of mapping complex three-dimensional flow fields within rivers, lakes, and estuaries. Using the Velocity Mapping Toolbox to process the ADCP data allows detailed visualization of the data, providing valuable information for a range of studies and applications.

Drug delivery from hydrophobic-modified mesoporous silicas: Control via modification level and site-selective modification

International Nuclear Information System (INIS)

Tang Qunli; Chen Yuxi; Chen Jianghua; Li Jin; Xu Yao; Wu Dong; Sun Yuhan

2010-01-01

Dimethylsilyl (DMS) modified mesoporous silicas were successfully prepared via co-condensation and post-grafting modification methods. The post-grafting modification was carried out by the reaction of the as-synthesized MCM-41 material (before CTAB removal) with diethoxydimethylsinale (DEDMS). N 2 adsorption-desorption and 29 Si MAS NMR characterization demonstrated that different amount of DMS groups were successfully incorporated into the co-condensation modified samples, and the functional DMS groups were placed selectively on the pore openings and external pore surfaces in the post-grafting modified samples. Subsequently, the controlled drug delivery properties from the resulting DMS-modified mesoporous silicas were investigated in detail. The drug adsorption experiments showed that the adsorption capacities were mainly depended on the content of silanol group (CSG) in the corresponding carriers. The in vitro tests exhibited that the incorporation of DMS groups greatly retarded the ibuprofen release rate. Moreover, the ibuprofen release profiles could be well modulated by varying DMS modification levels and site-selective distribution of functional groups in mesoporous carriers. - The distribution of DMS groups on the pore surfaces of the mesostructures strongly affects the drug release rate. The P-M41-1 and the P-M41-2 possess the close DMS modification levels as the C-M41-10, but the ibuprofen release rates from the P-M41-1 and P-M41-2 are much slower than that from the C-M41-10.

Density and temperature profile modifications with electron cyclotron power injection in quiescent double barrier discharges on DIII-D

International Nuclear Information System (INIS)

Casper, T A; Burrell, K H; Doyle, E J; Gohil, P; Lasnier, C J; Leonard, A W; Moller, J M; Osborne, T H; Snyder, P B; Thomas, D M; Weiland, J; West, W P

2006-01-01

Quiescent double barrier (QDB) conditions often form when an internal transport barrier is created with high-power neutral-beam injection into a quiescent H-mode (QH) plasma. These QH-modes offer an attractive, high-performance operating scenario for burning plasma experiments due to their quasi-stationarity and lack of edge localized modes. Our initial experiments and modelling using ECH/ECCD in QDB shots were designed to control the current profile and, indeed, we have observed a strong dependence on the q-profile when EC-power is used inside the core transport barrier region. While strong electron heating is observed with EC power injection, we also observe a drop in the other core parameters, namely ion temperature and rotation, electron density and impurity concentration. At onset and termination of the EC pulse, dynamically changing conditions are induced that provide a rapid evolution of T e /T i profiles accessible with 0.3 e /T i ) axis e /T i ratio as the ion temperature and density profiles flatten with this change in transport. The change in transport is consistent with a destabilization of ITG turbulence as inferred from the reduction of the stability threshold due to the change in T e /T i

Modification of a Turbulent Boundary Layer within a Homogeneous Concentration of Drag reducing Polymer Solution

Science.gov (United States)

Farsiani, Yasaman; Elbing, Brian

2017-11-01

High molecular weight polymer solutions in wall-bounded flows can reduce the local skin friction by as much as 80%. External flow studies have typical focused on injection of polymer within a developing turbulent boundary layer (TBL), allowing the concentration and drag reduction level to evolve with downstream distance. Modification of the log-law region of the TBL is directly related to drag reduction, but recent results suggest that the exact behavior is dependent on flow and polymer properties. Weissenberg number and the viscosity ratio (ratio of solvent viscosity to the zero-shear viscosity) are concentration dependent, thus the current study uses a polymer ocean (i.e. a homogenous concentration of polymer solution) with a developing TBL to eliminate uncertainty related to polymer properties. The near-wall modified TBL velocity profiles are acquired with particle image velocimetry. In the current presentation the mean velocity profiles and the corresponding flow (Reynolds number) and polymer (Weissenberg number, viscosity ratio, and length ratio) properties are reported. Note that the impact of polymer degradation on molecular weight will also be quantified and accounted for when estimating polymer properties This work was supported by NSF Grant 1604978.

Current meter and temperature profile data from current meter and buoy casts in the TOGA area of Pacific Ocean from 29 March 1991 to 24 December 1993 (NODC Accession 9900057)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Current meter and temperature profile data were collected using current meter and buoy casts in the TOGA area of Pacific Ocean from 29 March 1991 to 24 December...

Feedback control of current drive by using hybrid wave in tokamaks; Asservissement de la generation de courant par l`onde hybride dans un plasma de tokamak

Energy Technology Data Exchange (ETDEWEB)

Wijnands, T.J. [Association Euratom-CEA, Centre d`Etudes Nucleaires de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee]|[CEA Centre d`Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Direction des Sciences de la Matiere

1997-03-01

This work is focussed on an important and recent development in present day Controlled Nuclear Fusion Research and Tokamaks. The aim is to optimise the energy confinement for a certain magnetic configuration by adapting the radial distribution of the current. Of particular interest are feedback control scenarios with stationary modifications of the current profile using current, driven by Lower Hybrid waves. A new feedback control system has been developed for Tore Supra and has made a large number of new operation scenarios possible. In one of the experiments described here, there is no energy exchange between the poloidal field system and the plasma, the current is controlled by the power of the Lower Hybrid waves while the launched wave spectrum is used to optimise the current profile shape and the energy confinement. (author) 151 refs.

The computational nature of memory modification.

Science.gov (United States)

Gershman, Samuel J; Monfils, Marie-H; Norman, Kenneth A; Niv, Yael

2017-03-15

Retrieving a memory can modify its influence on subsequent behavior. We develop a computational theory of memory modification, according to which modification of a memory trace occurs through classical associative learning, but which memory trace is eligible for modification depends on a structure learning mechanism that discovers the units of association by segmenting the stream of experience into statistically distinct clusters (latent causes). New memories are formed when the structure learning mechanism infers that a new latent cause underlies current sensory observations. By the same token, old memories are modified when old and new sensory observations are inferred to have been generated by the same latent cause. We derive this framework from probabilistic principles, and present a computational implementation. Simulations demonstrate that our model can reproduce the major experimental findings from studies of memory modification in the Pavlovian conditioning literature.

Current meter and temperature profile data from current meter and buoy casts in the TOGA area of Pacific Ocean from 27 April 1993 to 09 June 1994 (NODC Accession 9700042)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Current meter and temperature profile data were collected using current meter and buoy casts in the TOGA area of Pacific Ocean from 27 April 1993 to 09 June 1994....

Measurement of fatigue crack growth using low-profile eddy-current sensors

International Nuclear Information System (INIS)

Ditchburn, R.J.; Ibrahim, M.E.; Burke, S.K.

2011-01-01

Conformable spiral coils show promise as permanently mounted eddy-current sensors for the detection and monitoring of surface-breaking cracks in electrically conductive structures. Flexibility and a low profile (typically less than 0.5 mm) are key advantages that allow the sensors to be unobtrusively mounted on curved surfaces and beneath surface coatings. Furthermore, these sensors can be permanently mounted in areas that would otherwise be difficult or impossible to reach without significant disassembly. The sensors can be activated and interrogated using the same well-established electromagnetic measurement principles in eddy-current nondestructive inspection. A material test machine was used to grow through-thickness fatigue crack in a compact-tension specimen made from the aerospace-grade aluminium alloy AA2014. The growth of the crack was examined by measuring the small impedance changes of planar spiral-coil sensors attached to the specimen. The results indicate that permanently attached conformable spiral coils can be used to detect a deep crack once it has grown beneath the sensor, and then to monitor subsequent crack growth.

High-resolution velocimetry in energetic tidal currents using a convergent-beam acoustic Doppler profiler

Science.gov (United States)

Sellar, Brian; Harding, Samuel; Richmond, Marshall

2015-08-01

An array of single-beam acoustic Doppler profilers has been developed for the high resolution measurement of three-dimensional tidal flow velocities and subsequently tested in an energetic tidal site. This configuration has been developed to increase spatial resolution of velocity measurements in comparison to conventional acoustic Doppler profilers (ADPs) which characteristically use divergent acoustic beams emanating from a single instrument. This is achieved using geometrically convergent acoustic beams creating a sample volume at the focal point of 0.03 m3. Away from the focal point, the array is also able to simultaneously reconstruct three-dimensional velocity components in a profile throughout the water column, and is referred to herein as a convergent-beam acoustic Doppler profiler (C-ADP). Mid-depth profiling is achieved through integration of the sensor platform with the operational commercial-scale Alstom 1 MW DeepGen-IV Tidal Turbine deployed at the European Marine Energy Center, Orkney Isles, UK. This proof-of-concept paper outlines the C-ADP system configuration and comparison to measurements provided by co-installed reference instrumentation. Comparison of C-ADP to standard divergent ADP (D-ADP) velocity measurements reveals a mean difference of 8 mm s-1, standard deviation of 18 mm s-1, and an order of magnitude reduction in realisable length scale. C-ADP focal point measurements compared to a proximal single-beam reference show peak cross-correlation coefficient of 0.96 over 4.0 s averaging period and a 47% reduction in Doppler noise. The dual functionality of the C-ADP as a profiling instrument with a high resolution focal point make this configuration a unique and valuable advancement in underwater velocimetry enabling improved quantification of flow turbulence. Since waves are simultaneously measured via profiled velocities, pressure measurements and surface detection, it is expected that derivatives of this system will be a powerful tool in

Numerical studies of active current profile control in the reversed-field pinch

International Nuclear Information System (INIS)

Dahlin, J-E; Scheffel, J; Anderson, J K

2007-01-01

Quenching of the reversed-field pinch (RFP) dynamo is observed in numerical simulations using current profile control. A novel algorithm employing active feedback of the dynamo field has been utilized. The quasi-steady state achieved represents an important improvement as compared with earlier numerical work and may indicate a direction for the design of future experiments. Both earlier and the novel schemes of feedback control result in quasi-single helicity states. The energy confinement time and poloidal beta are observed to be substantially increased, as compared with the conventional RFP, in both the cases. Different techniques for experimental implementation are discussed

Small-sized monitor of beam current and profile for the proton pulse electrostatic accelerator

International Nuclear Information System (INIS)

Getmanov, V.N.

1985-01-01

Design and principle of operation of current monitor and beam profile of range-coordinate type are described. Monitor operation peculiarities are discussed using diagnostics of a beam of 330-420 keV electrostatic pulse proton accelerator with a beam current of up to 20 mA, at a current density of up to 23 mA x cm -2 and wth pulse duraton of about 20 μs. The monitor consists of a vacuum-dense foil of 3.0+-0.1 μm in thickness (or 0.81+-0.0x- mg x cm -2 ) two grid electrodes, each containing 12 wires, and as solid copper bottom. Foil serves for chopping off background particles with a path lesser 3.0 μm and stands thermal pulse load up to 0.5 J/cm -2 . Grid electrode wires are oriented perpendicularly to lach other and form a two-coordinate secondary-emisson roughness indicator. The bothhom is used for measuring an absolute value of beam current

Considerations on ECFH current drive and bootstrap current for W VII-X

International Nuclear Information System (INIS)

Gasparino, U.; Maassberg, H.

1988-01-01

Low shear is the characteristic of all proposed Wendelstein VII-X configurations. To avoid low harmonic rational numbers within the rotational transform profile, the current contribution to the rotational transform, Δt a α I/B, should be typically less than 10%. This leads to an upper limit of 50 kA (at B = 2.5 T) for the tolerable net toroidal current. A considerable net toroidal current (bootstrap current) is expected by neoclassical theory in the plateau and the low-collisionality regimes. Both radial transport as well as the bootstrap current densities depend sensitively on the magnetic configuration (see A. Montvai, this workshop). In case of an axisymmetric configuration with dimension and plasma parameters as predicted for the high- regime of WVII-X ( ∼ 5%), this current (∼ 0.5/1 MA) would dominate the rotational transform profile. This requires a reduction of magnitude of the bootstrap current to some % of the value of an equivalent tokamak. This reduction must act on the current profile itself and should not be merely obtained by having two channels of currents of different sign at different radii. Due to the possibility of controlling absorbed power and driven current profiles, electron cyclotron waves are a natural candidate for current profile control. Linear calculations show the possibility to drive a counteracting current with a profile similar to the bootstrap one. For ∼ 5% conditions, however, the optimium current drive efficiency (η ∼ 10 kA per MW) is far too low to make ECF-current drive suitable

Impact of maternal obesity on the metabolic profiles of pregnant women and their offspring at birth

OpenAIRE

Desert , Romain; Canlet , Cécile; Costet , Nathalie; Cordier , Sylvaine; Bonvallot , Nathalie

2015-01-01

International audience; Obesity is currently an increasing public health problem. The intra-uterine environment plays a critical role in foetal development. The objective of this study is to investigate the association of obesity with modifications in the metabolic profiles of pregnant women, and their new-borns. Based on the PELAGIE cohort (Brittany, France), a sample of 321 pregnant women was divided into three groups according to their body mass index (BMI) (normal, over-weight and obese)....

Particle Distribution Modification by Low Amplitude Modes

International Nuclear Information System (INIS)

White, R.B.; Gorelenkov, N.; Heidbrink, W.W.; Van Zeeland, M.A.

2009-01-01

Modification of a high energy particle distribution by a spectrum of low amplitude modes is investigated using a guiding center code. Only through resonance are modes effective in modifying the distribution. Diagnostics are used to illustrate the mode-particle interaction and to find which effects are relevant in producing significant resonance, including kinetic Poincare plots and plots showing those orbits with time averaged mode-particle energy transfer. Effects of pitch angle scattering and drag are studied, as well as plasma rotation and time dependence of the equilibrium and mode frequencies. A specific example of changes observed in a DIII-D deuterium beam distribution in the presence of low amplitude experimentally validated Toroidal Alfven (TAE) eigenmodes and Reversed Shear Alfven (RSAE) eigenmodes is examined in detail. Comparison with experimental data shows that multiple low amplitude modes can account for significant modification of high energy beam particle distributions. It is found that there is a stochastic threshold for beam profile modification, and that the experimental amplitudes are only slightly above this threshold.

Dependence of CIT [Compact Ignition Tokamak] PF [poloidal field] coil currents on profile and shape parameters using the Control Matrix

International Nuclear Information System (INIS)

Strickler, D.J.; Peng, Y-K.M.; Jardin, S.C.; Pomphrey, N.

1990-01-01

The plasma shaping flexibility of the Compact Ignition Tokamak (CIT) poloidal field (PF) coil set is demonstrated through MHD equilibrium calculations of optimal PF coil current distributions and their variation with poloidal beta, internal inductance, plasma 95% elongation, and 95% triangularity. Calculations of the magnetic stored energy are used to compare solutions associated with various plasma parameters. The Control Matrix (CM) equilibrium code, together with the nonlinear equation and numerical optimization software packages HYBRD, and VMCON, respectively, are used to find equilibrium coil current distributions for fixed divertor geometry, volt-seconds, and plasma profiles in order to isolate the dependence on individual parameters. A reference equilibrium and coil current distribution are chosen, and correction currents dI are determined using the CM equilibrium method to obtain other specified plasma shapes. The reference equilibrium is the κ = 2 divertor at beginning of flattop (BOFT) with a minimum stored energy solution for the coil current distribution. The pressure profile function is fixed

Current and proposed revisions, changes, and modifications to American codes and standards to address packaging, handling, and transportation of radioactive materials and how they relate to comparable international regulations

International Nuclear Information System (INIS)

Borter, W.H.; Froehlich, C.H.

2004-01-01

This paper addresses current and proposed revisions, additions, and modifications to American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (BPVC) (i.e., ''ASMEthe Code'') Section III, Division 3 and American National Standards Institute (ANSI)/ASME N14.6. It provides insight into the ongoing processes of the associated committees and highlights important revisions, changes, and modifications to this Code and Standard. The ASME Code has developed and issued Division 3 to address items associated with the transportation and storage of radioactive materials. It currently only addresses ''General Requirements'' in Subsections WA and ''Class TP (Type B) Containments'' (Transportation Packages) in Subsection WB, but is in the process of adding a new Subsection WC to address ''Class SC'' (Storage Containments). ANSI/ASME Standard N14.6 which interacts with components constructed to Division 3 by addressinges special lifting devices for radioactive material shipping containers. This Standard is in the process of a complete re-write. This Code and Standard can be classified as ''dynamic'' in that their committees meet at least four times a year to evaluate proposed modifications and additions that reflect current safety practices in the nuclear industry. These evaluations include the possible addition of new materials, fabrication processes, examination methods, and testing requirements. An overview of this ongoing process is presented in this paper along with highlights of the more important proposed revisions, changes, and modifications and how they relate to United States (US) and international regulations and guidance like International Atomic Energy Agency (IAEA) Requirement No. TS-R-1

Confinement bifurcation by current density profile perturbation in TUMAN-3M tokamak

International Nuclear Information System (INIS)

Lebedev, S.V.; Andreiko, M.V.; Askinazi, L.G.

2001-01-01

In the recent experiments performed on TUMAN-3M the possibility to switch on/off the H-mode by current density profile perturbations has been shown. The j(r) perturbations were created by fast Current Ramp Up/Down or by Magnetic Compression produced by a fast increase of the toroidal magnetic field. It was found that the Current Ramp Up (CRU) and Magnetic Compression (MC) are useful means for H-mode triggering. The Current Ramp Down (CRD) triggers H-L transition. The difference in the j(r) behavior in these experiments suggests the peripheral current density may not be the critical parameter controlling L-H and H-L transitions. Confinement bifurcation in the above experiments could be explained by the unified mechanism: variation of a turbulent transport resulting from radial electric field emerging near the edge in the conditions of alternating toroidal electric field Ej and different electron and ion collisionalities. According to the suggested model the toroidal field E φ arising in the periphery during the CRU and MC processes amplifies Ware drift, which mainly influences electron component. As a result the favorable for the transition negative (inward directed) E r emerges. In the CRD scenario, when E φ is opposite to the total plasma current direction, the mechanism should generate positive E r , which is thought to be unfavorable for the H-mode. The experimental data on L-H and H-L transitions in various scenarios and the results of the modeling of E r emerging in the CRU experiment are presented in the paper. (author)

Measurements of Pfirsch-Schlueter current and pressure profile for the high density ECH plasmas in Heliotron DR

International Nuclear Information System (INIS)

Morimoto, S.; Yanagi, N.; Nakasuga, M.; Obiki, T.; Iiyoshi, A.; Uo, K.

1988-01-01

The Pfirsch-Schlueter current and pressure profiles are estimated from magnetic measurements for high density electron cyclotron heating (ECH) plasmas (n-bar e =(2-3)x10 13 cm -3 , T e0 =200-400 eV, (β) 0 (1-(r/a) 2 ) s , is about two in macroscopically stable plasmas. A fast loss of plasma energy from the centre to the periphery is observed during the onset of the MHD instability. This method of measuring the pressure profile shape is simple and useful for heliotron type devices. (author). 20 refs, 8 figs, 1 tab

Methods and Systems for Use of an Acoustic Doppler Current Profiler for Measurement of Compact Jets

National Research Council Canada - National Science Library

Hendricks, Peter J

2007-01-01

... an Acoustic Doppler Current Profiler (ADCP). The ADCP is a four-beam, Janus-type ADCP having beams aligned so that each of the beams is at an angle of about 200 to 300 to vertical and at 450 to the fore and aft axis of the vessel, such that two...

The computational nature of memory modification

Science.gov (United States)

Gershman, Samuel J; Monfils, Marie-H; Norman, Kenneth A; Niv, Yael

2017-01-01

Retrieving a memory can modify its influence on subsequent behavior. We develop a computational theory of memory modification, according to which modification of a memory trace occurs through classical associative learning, but which memory trace is eligible for modification depends on a structure learning mechanism that discovers the units of association by segmenting the stream of experience into statistically distinct clusters (latent causes). New memories are formed when the structure learning mechanism infers that a new latent cause underlies current sensory observations. By the same token, old memories are modified when old and new sensory observations are inferred to have been generated by the same latent cause. We derive this framework from probabilistic principles, and present a computational implementation. Simulations demonstrate that our model can reproduce the major experimental findings from studies of memory modification in the Pavlovian conditioning literature. DOI: http://dx.doi.org/10.7554/eLife.23763.001 PMID:28294944

Resistive evolution of current profile in tokamaks, application to the optimization of Tore-supra plasma discharges; Evolution resistive du profil de courant dans les Tokamaks, application a l'optimisation des decharges de Tore Supra

Energy Technology Data Exchange (ETDEWEB)

Bregeon, R

1999-03-01

In Tokamak plasma physics, current profile shaping has now become a key issue to improve the confinement properties of the plasma discharge. The objective of this work is to study the processes governing the current diffusion when non-inductive current are playing a major role in the discharge. Ultimately, this study aims to identify the key parameters to control the plasma current density profile with external current drive heating systems such as Lower Hybrid Current drive (LHCD) or self generated current drive such as the bootstrap current. Principles of non inductive current drive and heating systems are introduced as well as bootstrap current mechanisms. Then we present the experimental study of plasma parallel electric conductivity to validate existing models. Using these results, the poloidal magnetic field flux diffusion is modelled, using toroidal co-ordinates in order to give an accurate description of the current density profiles evolution. The initial and boundary conditions required for numerical resolution of the diffusion equation are also presented. Finally, we conclude this work with the simulations of two discharges: one with Fast Wave Electron Heating and the second using Lower Hybrid Current Drive. These simulations have multiples aims: validity test of our numerical tool and to show some limits of cylindrical models. Test of electric conductivity and bootstrap current models. To identify the key parameters involved in the current diffusion processes of a high performance plasma discharge on Tore Supra. Such simulations are crucial to determine the amount of non-inductive current required to control and sustain long plasma discharges in steady state. (author)

Dependence of the DIII-D beta limit on the current profile

Energy Technology Data Exchange (ETDEWEB)

Strait, E.J.; Chu, M.S.; Ferron, J.R.; Lao, L.L.; Osborne, T.H.; Taylor, T.S.; Turnbull, A.D. (General Atomics, San Diego, CA (United States)); Lazarus, E.A. (Oak Ridge National Lab., TN (United States))

1991-01-01

The maximum beta values achieved in DIII-D are not fully described by the simple scaling law [beta][sub max][proportional to]I/aB. There is, in addition, a dependence on the form of the current profile as parameterized by the safety factor q and internal inductance l[sub i]. The maximum experimentally achieved value of normalized beta [beta][sub N] = [beta]/(I/aB) varies from 3.5 at low safety factor q (q[sub 95]<3) to 5 at higher values of q. At low q, discharges are terminated by disruptions at high [beta][sub N] and at both the low and high l[sub i] boundaries of the stable range. These disruptions are attributed to external and global kink modes. At higher q, such disruptions are much less frequent, and beta is limited by slowly growing resistive modes, fishbones, and possibly by ballooning modes. At each value of q, the maximum beta tends to increase with internal inductance l[sub i]. A numerical study of kink mode stability has shown a similar trend for optimized pressure profiles. These observations have suggested a new scaling law for the operational beta limit: [beta][sub max]=4l[sub i](I/aB), which fits the DIII-D data well. (author) 13 refs., 4 figs.

Internal m=1, n=1 helical mode in a tokamak with nonmonotonic current profile

International Nuclear Information System (INIS)

Kuvshinov, B.N.; Mikhajlovskij, A.B.

1988-01-01

Internal helical mode in a tokamak with two resonance surfaces, on which storing coefficient reduces to unity is studied theoretically. A general criterion for the investigated perturbations stability is obtained. Dispersion equation, describing both ideal and resistive helical modes, is derived. Analytic calculations for the case of perturbations localized near the tokamak axis are made. It is shown that in the framework of standard ideal hydrodynamics such perturbations are unstable at characteristic nonmonotonous profiles of the current

Technical Note: Influence of Compton currents on profile measurements in small-volume ion chambers

Energy Technology Data Exchange (ETDEWEB)

Tanny, Sean; Sperling, Nicholas; Parsai, E. Ishmael, E-mail: e.parsai@utoledo.edu [Department of Radiation Oncology, University of Toledo Medical Center, 1325 Conference Drive, Toledo, Ohio 43614 (United States); Holmes, Shannon [Standard Imaging, 3120 Deming Way, Middleton, Wisconsin 53562 (United States)

2015-10-15

Purpose: This work is to evaluate the effects of Compton current generation in three small-volume ionization chambers on measured beam characteristics for electron fields. Methods: Beam scans were performed using Exradin A16, A26, and PTW 31014 microchambers. Scans with varying chamber components shielded were performed. Static point measurements, output factors, and cable only irradiations were performed to determine the contribution of Compton currents to various components of the chamber. Monte Carlo simulations were performed to evaluate why one microchamber showed a significant reduction in Compton current generation. Results: Beam profiles demonstrated significant distortion for two of the three chambers when scanned parallel to the chamber axis, produced by electron deposition within the wire. Measurements of ionization produced within the cable identified Compton current generation as the cause of these distortions. The size of the central collecting wire was found to have the greatest influence on the magnitude of Compton current generation. Conclusions: Microchambers can demonstrate significant (>5%) deviations from properties as measured with larger volume chambers (0.125 cm{sup 3} and above). These deviations can be substantially reduced by averaging measurements conducted at opposite polarities.

Ocean Current Velocity Moored Time-Series Records, collected from moored Acoustic Doppler Current Profilers (ADCP) during 2011 near Grammanik Bank SPAG and Frenchcap Cay, USVI (NODC Accession 0088064)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Nortek 600kHz Aquadopp acoustic current profilers were deployed between April 2011 and September 2011 on shallow water moorings located on the coastal shelf south of...

Aircraft Modifications: Assessing the Current State of Air Force Aircraft Modifications and the Implications for Future Military Capability

Science.gov (United States)

2007-01-25

J IVF MNA M J J DA S 0 TM C J JV A i KIT DELIVERYO TYS h. KIT INSTALL OTYS-DEPOT JI I- - - 1. KIT INSTALL OTYS-TEAM 24. INFLATED COST SUMMgARIES BY...as a part of a study examining the costing of modifying Air Force weapon systems. Over the same time that the concept for this dissertation was...planning and modernization. The project documented here was conducted within the Costing of Modifications and Upgrades program of RAND’s Project AIR

Modifying locally the safety profile to improve the confinement of magnetic field lines in tokamak plasmas

International Nuclear Information System (INIS)

Constantinescu, D.; Firpo, M.-C.

2012-01-01

Using Hamiltonian models for the magnetic field lines, we propose a methodology to improve their confinement through the creation of transport barriers. A local modification of the safety profile creating a low-shear zone is shown to be sufficient to locally enhance drastically the regularity of the magnetic field lines without requesting a reversed shear. The optimal benefits of low-shear are obtained when the value q 0 of the safety profile in the low-shear zone is sufficiently far from the main resonance values m/n with low m and n, in the case of large enough values of those (m, n) mode amplitudes. A practical implementation in tokamak plasmas should involve electron cyclotron current drive to locally modify the magnetic shear. (paper)

Recent Advances in Attention Bias Modification for Substance Addictions

Directory of Open Access Journals (Sweden)

Melvyn Weibin Zhang

2018-04-01

Full Text Available Research on attentional bias modification has increased since 2014. A recent meta-analysis demonstrates evidence for bias modification for substance disorders, including alcohol and tobacco use disorders. Several pharmacological trials have shown that pharmacological agents can attenuate and modify such attentional bias. The pharmacological trials that have appeared to date have produced mixed results, which has clinical implications. Developments in Internet and mobile technologies have transformed how attention bias modification is currently being achieved. There remains great potential for further research that examines the efficacy of technology-aided attention bias interventions.

Sampling Modification Effects in the Subgingival Microbiome Profile of Healthy Children

Science.gov (United States)

Santigli, Elisabeth; Trajanoski, Slave; Eberhard, Katharina; Klug, Barbara

2017-01-01

grouping by sampling modes (p = 0.914 by R2 = 0.09). Conclusion: A slight modification of sampling mode has minor effects corresponding to a natural variability in the microbiome profiles of healthy children. The inter-individual variability in subgingival microprints is greater than intra-individual differences. Statistical analyses of microbial populations should consider this baseline variability and move beyond mere quantification with input from visual analytics. Comparative results are difficult to summarize as methods for studying huge datasets are still evolving. Advanced approaches are needed for sample size calculations in clinical settings. PMID:28149291

Sampling Modification Effects in the Subgingival Microbiome Profile of Healthy Children.

Science.gov (United States)

Santigli, Elisabeth; Trajanoski, Slave; Eberhard, Katharina; Klug, Barbara

2016-01-01

sampling modes ( p = 0.914 by R 2 = 0.09). Conclusion: A slight modification of sampling mode has minor effects corresponding to a natural variability in the microbiome profiles of healthy children. The inter-individual variability in subgingival microprints is greater than intra-individual differences. Statistical analyses of microbial populations should consider this baseline variability and move beyond mere quantification with input from visual analytics. Comparative results are difficult to summarize as methods for studying huge datasets are still evolving. Advanced approaches are needed for sample size calculations in clinical settings.

A CO2 laser polarimeter for measurement of plasma current profile in Alcator C-Mod

International Nuclear Information System (INIS)

Ma, C.H.; Hutchinson, D.P.; Richards, R.K.; Irby, J.; Luke, T.

1994-01-01

A multichannel infrared polarimeter system for measurement of the plasma current profile in Alcator C-Mod has been designed, constructed, and tested. The system utilizes a cw CO 2 , laser at a wavelength of 10.6 μm. An electro-optic polarization-modulation technique has been used to achieve the high sensitivity required for the measurement. The recent results of the measurements as well as the feasibility of its application on ITER are presented

EG and G electron linac modifications

International Nuclear Information System (INIS)

Norris, N.J.; Detch, J.L.; Kocimski, S.M.; Sawyer, C.R.; Hudson, C.L.

1986-01-01

The electron linear accelerator at EG and G/EM, Santa Barbara Operations, installed in 1963, has been subsequently modified to produce short, intense beam pulses used in the test, calibration and development of many types of fast radiation detectors and systems. The first practical use of the single RF pulse operation, now used in many accelerators, was demonstrated on this accelerator in the late 60s. A major three-year modification, to replace obsolete equipment and bring all the subsystems up to the current state of the art, has increased the beam intensity, stability and reliability. These modifications are discussed

Multiplexed Thiol Reactivity Profiling for Target Discovery of Electrophilic Natural Products.

Science.gov (United States)

Tian, Caiping; Sun, Rui; Liu, Keke; Fu, Ling; Liu, Xiaoyu; Zhou, Wanqi; Yang, Yong; Yang, Jing

2017-11-16

Electrophilic groups, such as Michael acceptors, expoxides, are common motifs in natural products (NPs). Electrophilic NPs can act through covalent modification of cysteinyl thiols on functional proteins, and exhibit potent cytotoxicity and anti-inflammatory/cancer activities. Here we describe a new chemoproteomic strategy, termed multiplexed thiol reactivity profiling (MTRP), and its use in target discovery of electrophilic NPs. We demonstrate the utility of MTRP by identifying cellular targets of gambogic acid, an electrophilic NP that is currently under evaluation in clinical trials as anticancer agent. Moreover, MTRP enables simultaneous comparison of seven structurally diversified α,β-unsaturated γ-lactones, which provides insights into the relative proteomic reactivity and target preference of diverse structural scaffolds coupled to a common electrophilic motif and reveals various potential druggable targets with liganded cysteines. We anticipate that this new method for thiol reactivity profiling in a multiplexed manner will find broad application in redox biology and drug discovery. Copyright © 2017 Elsevier Ltd. All rights reserved.

10 CFR 830 Major Modification Determination for Emergency Firewater Injection System Replacement

International Nuclear Information System (INIS)

Duckwitz, Noel

2011-01-01

The continued safe and reliable operation of the ATR is critical to the Department of Energy (DOE) Office of Nuclear Energy (NE) mission. While ATR is safely fulfilling current mission requirements, a variety of aging and obsolescence issues challenge ATR engineering and maintenance personnel's capability to sustain ATR over the long term. First documented in a series of independent assessments, beginning with an OA Environmental Safety and Health Assessment conducted in 2003, the issues were validated in a detailed Material Condition Assessment (MCA) conducted as a part of the ATR Life Extension Program in 2007. Accordingly, near term replacement of aging and obsolescent original ATR equipment has become important to ensure ATR capability in support of NE's long term national missions. To that end, a mission needs statement has been prepared for a non-major system acquisition which is comprised of three interdependent sub-projects. The first project will replace the existent diesel-electrical bus (E-3), switchgear, and the fifty year old antiquated marine diesels with commercial power that is backed with safety-related emergency diesel generators (EDGs), switchgear, and uninterruptible power supply. The second project will replace the four, obsolete, original primary coolant pumps and motors. The third project, the subject of this major modification determination, will replace the current emergency firewater injection system (EFIS). The replacement water injection system will function as the primary emergency water injection system with the EFIS being retained as a defense-in-depth backup. Completion of this and the two other age-related projects (replacement of the ATR diesel bus (E-3) and switchgear and replacement of the existent aged primary coolant pumps and motors) will resolve major age-related operational issues plus make a significant contribution in sustaining the ATR safety and reliability profile. The major modification criteria evaluation of the

Variance of discharge estimates sampled using acoustic Doppler current profilers from moving boats

Science.gov (United States)

Garcia, Carlos M.; Tarrab, Leticia; Oberg, Kevin; Szupiany, Ricardo; Cantero, Mariano I.

2012-01-01

This paper presents a model for quantifying the random errors (i.e., variance) of acoustic Doppler current profiler (ADCP) discharge measurements from moving boats for different sampling times. The model focuses on the random processes in the sampled flow field and has been developed using statistical methods currently available for uncertainty analysis of velocity time series. Analysis of field data collected using ADCP from moving boats from three natural rivers of varying sizes and flow conditions shows that, even though the estimate of the integral time scale of the actual turbulent flow field is larger than the sampling interval, the integral time scale of the sampled flow field is on the order of the sampling interval. Thus, an equation for computing the variance error in discharge measurements associated with different sampling times, assuming uncorrelated flow fields is appropriate. The approach is used to help define optimal sampling strategies by choosing the exposure time required for ADCPs to accurately measure flow discharge.

Radial profile of pressure in a storm ring current as a function of D st

Science.gov (United States)

Kovtyukh, A. S.

2010-06-01

Using satellite data obtained near the equatorial plane during 12 magnetic storms with amplitudes from -61 down to -422 nT, the dependences of maximum in L-profile of pressure ( L m) of the ring current (RC) on the current value of D st are constructed, and their analytical approximations are derived. It is established that function L m( D st ) is steeper on the phase of recovery than during the storm’s main phase. The form of the outer edge of experimental radial profiles of RC pressure is studied, and it is demonstrated to correspond to exponential growth of the total energy of RC particles on a given L shell with decreasing L. It is shown that during the storms’ main phase the ratio of plasma and magnetic field pressures at the RC maximum does not practically depend on the storm strength and L m value. This fact reflects resistance of the Earth’s magnetic field to RC expansion, and testifies that during storms the possibilities of injection to small L are limited for RC particles. During the storms’ recovery phase this ratio quickly increases with increasing L m, which reflects an increased fraction of plasma in the total pressure balance. It is demonstrated that function L m( D st ) is derived for the main phase of storms from the equations of drift motion of RC ions in electrical and magnetic fields, reflecting the dipole character of magnetic field and scale invariance of the pattern of particle convection near the RC maximum. For the recovery phase it is obtained from the Dessler-Parker-Sckopke relationship. The obtained regularities allow one to judge about the radial profile of RC pressure from ground-based magnetic measurements (data on the D st variation).

QRev—Software for computation and quality assurance of acoustic doppler current profiler moving-boat streamflow measurements—User’s manual for version 2.8

Science.gov (United States)

Mueller, David S.

2016-05-12

The software program, QRev computes the discharge from moving-boat acoustic Doppler current profiler measurements using data collected with any of the Teledyne RD Instrument or SonTek bottom tracking acoustic Doppler current profilers. The computation of discharge is independent of the manufacturer of the acoustic Doppler current profiler because QRev applies consistent algorithms independent of the data source. In addition, QRev automates filtering and quality checking of the collected data and provides feedback to the user of potential quality issues with the measurement. Various statistics and characteristics of the measurement, in addition to a simple uncertainty assessment are provided to the user to assist them in properly rating the measurement. QRev saves an extensible markup language file that can be imported into databases or electronic field notes software. The user interacts with QRev through a tablet-friendly graphical user interface. This report is the manual for version 2.8 of QRev.

Shear Alfven Wave Injection in the Magnetosphere by Ionospheric Modifications in the Absence of Electrojet Currents

Science.gov (United States)

Papadopoulos, K.; Eliasson, B.; Shao, X.; Labenski, J.; Chang, C.

2011-12-01

A new concept of generating ionospheric currents in the ULF/ELF range with modulated HF heating using ground-based transmitters even in the absence of electrojet currents is presented. The new concept relies on using HF heating of the F-region to modulate the electron temperature and has been given the name Ionospheric Current Drive (ICD). In ICD, the pressure gradient associated with anomalous or collisional F-region electron heating drives a local diamagnetic current that acts as an antenna to inject mainly Magneto-Sonic (MS) waves in the ionospheric plasma. The electric field associated with the MS wave drives Hall currents when it reaches the E region of the ionosphere. The Hall currents act as a secondary antenna that inject waves in the Earth-Ionosphere Waveguide (EIW) below and shear Alfven waves or EMIC waves upwards towards the conjugate regions. The paper presents: (i) Theoretical results using a cold Hall MHD model to study ICD and the generation of ULF/ELF waves by the modulation of the electron pressure at the F2-region with an intense HF electromagnetic wave. The model solves equations governing the dynamics of the shear Alfven and magnetosonic modes, of the damped modes in the diffusive Pedersen layer, and of the weakly damped helicon wave mode in the Hall-dominated E-region. The model incorporates realistic profile of the ionospheric conductivities and magnetic field configuration. We use the model to simulate propagation and dynamics of the low-frequency waves and their injection into the magnetosphere from the HAARP and Arecibo ionospheric heaters. (ii) Proof of principle experiments using the HAARP ionospheric heater in conjunction with measurements by the DEMETER satellite This work is supported by ONR MURI grant and DARPA BRIOCHE Program

Inter-ELM evolution of the edge current density profile on the ASDEX Upgrade tokamak

International Nuclear Information System (INIS)

Dunne, Michael G.

2014-01-01

The sudden decrease of plasma stored energy and subsequent power deposition on the first wall of a tokamak device due to edge localised modes (ELMs) is potentially detrimental to the success of a future fusion reactor. Understanding and control of ELMs is critical for the longevity of these devices and also to maximise their performance. The commonly accepted picture of ELMs posits a critical pressure gradient and current density in the plasma edge, above which coupled magnetohydrodynamic (MHD) peeling-ballooning modes are driven unstable. Much analysis has been presented in recent years on the spatial and temporal evolution of the edge pressure gradient. However, the edge current density has typically been overlooked due to the difficulties in measuring this quantity. In this thesis, a novel method of current density recovery is presented, using the equilibrium solver CLISTE to reconstruct a high resolution equilibrium utilising both external magnetic and internal edge kinetic data measured on the ASDEX Upgrade (AUG) tokamak. The evolution of the edge current density relative to an ELM crash is presented, showing that a resistive delay in the buildup of the current density is unlikely. An uncertainty analysis shows that the edge current density can be determined with an accuracy consistent with that of the kinetic data used. A comparison with neoclassical theory demonstrates excellent agreement between the current density determined by CLISTE and the calculated profiles. Three ELM mitigation regimes are investigated: Type-II ELMs, ELMs suppressed by external magnetic perturbations (MPs), and Nitrogen seeded ELMs. In the first two cases, the current density is found to decrease as mitigation onsets, indicating a more ballooning-like plasma behaviour. In the latter case, the flux surface averaged current density can decrease while the local current density increases, thus providing a mechanism to suppress both the peeling and ballooning modes.

Inter-ELM evolution of the edge current density profile on the ASDEX Upgrade tokamak

Energy Technology Data Exchange (ETDEWEB)

Dunne, Michael G.

2014-02-15

The sudden decrease of plasma stored energy and subsequent power deposition on the first wall of a tokamak device due to edge localised modes (ELMs) is potentially detrimental to the success of a future fusion reactor. Understanding and control of ELMs is critical for the longevity of these devices and also to maximise their performance. The commonly accepted picture of ELMs posits a critical pressure gradient and current density in the plasma edge, above which coupled magnetohydrodynamic (MHD) peeling-ballooning modes are driven unstable. Much analysis has been presented in recent years on the spatial and temporal evolution of the edge pressure gradient. However, the edge current density has typically been overlooked due to the difficulties in measuring this quantity. In this thesis, a novel method of current density recovery is presented, using the equilibrium solver CLISTE to reconstruct a high resolution equilibrium utilising both external magnetic and internal edge kinetic data measured on the ASDEX Upgrade (AUG) tokamak. The evolution of the edge current density relative to an ELM crash is presented, showing that a resistive delay in the buildup of the current density is unlikely. An uncertainty analysis shows that the edge current density can be determined with an accuracy consistent with that of the kinetic data used. A comparison with neoclassical theory demonstrates excellent agreement between the current density determined by CLISTE and the calculated profiles. Three ELM mitigation regimes are investigated: Type-II ELMs, ELMs suppressed by external magnetic perturbations (MPs), and Nitrogen seeded ELMs. In the first two cases, the current density is found to decrease as mitigation onsets, indicating a more ballooning-like plasma behaviour. In the latter case, the flux surface averaged current density can decrease while the local current density increases, thus providing a mechanism to suppress both the peeling and ballooning modes.

HMCan-diff: a method to detect changes in histone modifications in cells with different genetic characteristics

KAUST Repository

Ashoor, Haitham

2016-12-19

Comparing histone modification profiles between cancer and normal states, or across different tumor samples, can provide insights into understanding cancer initiation, progression and response to therapy. ChIP-seq histone modification data of cancer samples are distorted by copy number variation innate to any cancer cell. We present HMCan-diff, the first method designed to analyze ChIP-seq data to detect changes in histone modifications between two cancer samples of different genetic backgrounds, or between a cancer sample and a normal control. HMCan-diff explicitly corrects for copy number bias, and for other biases in the ChIP-seq data, which significantly improves prediction accuracy compared to methods that do not consider such corrections. On in silico simulated ChIP-seq data generated using genomes with differences in copy number profiles, HMCan-diff shows a much better performance compared to other methods that have no correction for copy number bias. Additionally, we benchmarked HMCan-diff on four experimental datasets, characterizing two histone marks in two different scenarios. We correlated changes in histone modifications between a cancer and a normal control sample with changes in gene expression. On all experimental datasets, HMCan-diff demonstrated better performance compared to the other methods.

Fast wave experiments in LAPD: RF sheaths, convective cells and density modifications

Science.gov (United States)

Carter, T. A.; van Compernolle, B.; Martin, M.; Gekelman, W.; Pribyl, P.; van Eester, D.; Crombe, K.; Perkins, R.; Lau, C.; Martin, E.; Caughman, J.; Tripathi, S. K. P.; Vincena, S.

2017-10-01

An overview is presented of recent work on ICRF physics at the Large Plasma Device (LAPD) at UCLA. The LAPD has typical plasma parameters ne 1012 -1013 cm-3, Te 1 - 10 eV and B 1000 G. A new high-power ( 150 kW) RF system and fast wave antenna have been developed for LAPD. The source runs at a frequency of 2.4 MHz, corresponding to 1 - 7fci , depending on plasma parameters. Evidence of rectified RF sheaths is seen in large increases ( 10Te) in the plasma potential on field lines connected to the antenna. The rectified potential scales linearly with antenna current. The rectified RF sheaths set up convective cells of local E × B flows, measured indirectly by potential measurements, and measured directly with Mach probes. At high antenna powers substantial modifications of the density profile were observed. The plasma density profile initially exhibits transient low frequency oscillations (10 kHz). The amplitude of the fast wave fields in the core plasma is modulated at the same low frequency, suggesting fast wave coupling is affected by the density rearrangement. Work performed at the Basic Plasma Science Facility, supported jointly by the National Science Foundation and the Department of Energy.

Measuring discharge with acoustic Doppler current profilers from a moving boat

Science.gov (United States)

Mueller, David S.; Wagner, Chad R.; Rehmel, Michael S.; Oberg, Kevin A.; Rainville, Francois

2013-01-01

The use of acoustic Doppler current profilers (ADCPs) from a moving boat is now a commonly used method for measuring streamflow. The technology and methods for making ADCP-based discharge measurements are different from the technology and methods used to make traditional discharge measurements with mechanical meters. Although the ADCP is a valuable tool for measuring streamflow, it is only accurate when used with appropriate techniques. This report presents guidance on the use of ADCPs for measuring streamflow; this guidance is based on the experience of U.S. Geological Survey employees and published reports, papers, and memorandums of the U.S. Geological Survey. The guidance is presented in a logical progression, from predeployment planning, to field data collection, and finally to post processing of the collected data. Acoustic Doppler technology and the instruments currently (2013) available also are discussed to highlight the advantages and limitations of the technology. More in-depth, technical explanations of how an ADCP measures streamflow and what to do when measuring in moving-bed conditions are presented in the appendixes. ADCP users need to know the proper procedures for measuring discharge from a moving boat and why those procedures are required, so that when the user encounters unusual field conditions, the procedures can be adapted without sacrificing the accuracy of the streamflow-measurement data.

Albumin modification and fragmentation in renal disease.

Science.gov (United States)

Donadio, Carlo; Tognotti, Danika; Donadio, Elena

2012-02-18

Albumin is the most important antioxidant substance in plasma and performs many physiological functions. Furthermore, albumin is the major carrier of endogenous molecules and exogenous ligands. This paper reviews the importance of post-translational modifications of albumin and fragments thereof in patients with renal disease. First, current views and controversies on renal handling of proteins, mainly albumin, will be discussed. Post-translational modifications, namely the fragmentation of albumin found with proteomic techniques in nephrotic patients, diabetics, and ESRD patients will be presented and discussed. It is reasonable to hypothesize that proteolytic fragmentation of serum albumin is due to a higher susceptibility to proteases, induced by oxidative stress. The clinical relevance of the fragmentation of albumin has not yet been established. These modifications could affect some physiological functions of albumin and have a patho-physiological role in uremic syndrome. Proteomic analysis of serum allows the identification of over-expressed proteins and can detect post-translational modifications of serum proteins, hitherto hidden, using standard laboratory techniques. Copyright © 2011 Elsevier B.V. All rights reserved.

Hull-Mounted Acoustic Doppler Current Profiler Data (SADCP) collected aboard the NOAA Ship NANCY FOSTER during cruise NF-10-01 and NF-10-02

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Upper ocean current velocity measurements collected with NOAA Ship NANCY FOSTER's Teledyne RD Instruments 150 kHz hull-mounted acoustic Doppler current profiler...

Cigar Product Modification Among High School Youth.

Science.gov (United States)

Trapl, Erika S; Koopman Gonzalez, Sarah J; Cofie, Leslie; Yoder, Laura D; Frank, Jean; Sterling, Kymberle L

2018-02-07

Prevalence of cigar use has been increasing among youth. Research indicates that youth are modifying cigar products either by "freaking" (ie, removing the filter paper) or "blunting" (removing the tobacco and supplementing or replacing with marijuana), yet little is known about youth who engage in this behavior. Thus, this study examines demographic and concurrent substance use behaviors of youth who modify cigars. Data from the 2013 Cuyahoga County Youth Risk Behavior survey were examined (n = 16 855). The survey collected data on demographics, cigar product use, cigar modification behaviors, and current cigarette, hookah and marijuana use. Responses to cigar product use items were used to create a composite to classify youth in one of eight unique user categories. Univariate and bivariate statistics were calculated using SPSS complex samples procedures. Overall, 15.2% reported current cigar product use, 11.0% reported current freaking, and 18.5% reported current blunt use; taken together, 25.3% of respondents reported any current use of a cigar product. When examined by user category, of those who endorsed any cigar product use, cigars, cigarillos, and little cigars use only was most endorsed (26.3%), followed by Blunt only (25.2%) and all three (ie, cigars, cigarillos, and little cigars, freaking, and blunting; 17.4%). A substantial proportion of high school youth who report using cigar products are modifying them in some way, with nearly half freaking and nearly two-thirds blunting. Given the FDA Center for Tobacco products recent extension of its regulatory authority to include cigar products, it is imperative to understand more about the prevalence of and reasons for cigar modification behaviors. Although the FDA has recently enacted regulatory authority over cigar products, little is known about cigar product modification. This is the first study to concurrently examine two unique cigar modification behaviors, "freaking" (ie, removing the filter paper) and

Trophic interaction modifications: an empirical and theoretical framework.

Science.gov (United States)

Terry, J Christopher D; Morris, Rebecca J; Bonsall, Michael B

2017-10-01

Consumer-resource interactions are often influenced by other species in the community. At present these 'trophic interaction modifications' are rarely included in ecological models despite demonstrations that they can drive system dynamics. Here, we advocate and extend an approach that has the potential to unite and represent this key group of non-trophic interactions by emphasising the change to trophic interactions induced by modifying species. We highlight the opportunities this approach brings in comparison to frameworks that coerce trophic interaction modifications into pairwise relationships. To establish common frames of reference and explore the value of the approach, we set out a range of metrics for the 'strength' of an interaction modification which incorporate increasing levels of contextual information about the system. Through demonstrations in three-species model systems, we establish that these metrics capture complimentary aspects of interaction modifications. We show how the approach can be used in a range of empirical contexts; we identify as specific gaps in current understanding experiments with multiple levels of modifier species and the distributions of modifications in networks. The trophic interaction modification approach we propose can motivate and unite empirical and theoretical studies of system dynamics, providing a route to confront ecological complexity. © 2017 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.

Variations of Histone Modification Patterns: Contributions of Inter-plant Variability and Technical Factors

Directory of Open Access Journals (Sweden)

Sylva Brabencová

2017-12-01

Full Text Available Inter-individual variability of conspecific plants is governed by differences in their genetically determined growth and development traits, environmental conditions, and adaptive responses under epigenetic control involving histone post-translational modifications. The apparent variability in histone modifications among plants might be increased by technical variation introduced in sample processing during epigenetic analyses. Thus, to detect true variations in epigenetic histone patterns associated with given factors, the basal variability among samples that is not associated with them must be estimated. To improve knowledge of relative contribution of biological and technical variation, mass spectrometry was used to examine histone modification patterns (acetylation and methylation among Arabidopsis thaliana plants of ecotypes Columbia 0 (Col-0 and Wassilewskija (Ws homogenized by two techniques (grinding in a cryomill or with a mortar and pestle. We found little difference in histone modification profiles between the ecotypes. However, in comparison of the biological and technical components of variability, we found consistently higher inter-individual variability in histone mark levels among Ws plants than among Col-0 plants (grown from seeds collected either from single plants or sets of plants. Thus, more replicates of Ws would be needed for rigorous analysis of epigenetic marks. Regarding technical variability, the cryomill introduced detectably more heterogeneity in the data than the mortar and pestle treatment, but mass spectrometric analyses had minor apparent effects. Our study shows that it is essential to consider inter-sample variance and estimate suitable numbers of biological replicates for statistical analysis for each studied organism when investigating changes in epigenetic histone profiles.

Variations of Histone Modification Patterns: Contributions of Inter-plant Variability and Technical Factors.

Science.gov (United States)

Brabencová, Sylva; Ihnatová, Ivana; Potěšil, David; Fojtová, Miloslava; Fajkus, Jiří; Zdráhal, Zbyněk; Lochmanová, Gabriela

2017-01-01

Inter-individual variability of conspecific plants is governed by differences in their genetically determined growth and development traits, environmental conditions, and adaptive responses under epigenetic control involving histone post-translational modifications. The apparent variability in histone modifications among plants might be increased by technical variation introduced in sample processing during epigenetic analyses. Thus, to detect true variations in epigenetic histone patterns associated with given factors, the basal variability among samples that is not associated with them must be estimated. To improve knowledge of relative contribution of biological and technical variation, mass spectrometry was used to examine histone modification patterns (acetylation and methylation) among Arabidopsis thaliana plants of ecotypes Columbia 0 (Col-0) and Wassilewskija (Ws) homogenized by two techniques (grinding in a cryomill or with a mortar and pestle). We found little difference in histone modification profiles between the ecotypes. However, in comparison of the biological and technical components of variability, we found consistently higher inter-individual variability in histone mark levels among Ws plants than among Col-0 plants (grown from seeds collected either from single plants or sets of plants). Thus, more replicates of Ws would be needed for rigorous analysis of epigenetic marks. Regarding technical variability, the cryomill introduced detectably more heterogeneity in the data than the mortar and pestle treatment, but mass spectrometric analyses had minor apparent effects. Our study shows that it is essential to consider inter-sample variance and estimate suitable numbers of biological replicates for statistical analysis for each studied organism when investigating changes in epigenetic histone profiles.

Use of profile hidden Markov models in viral discovery: current insights

Directory of Open Access Journals (Sweden)

Reyes A

2017-07-01

Full Text Available Alejandro Reyes,1–3 João Marcelo P Alves,4 Alan Mitchell Durham,5 Arthur Gruber4 1Department of Biological Sciences, Universidad de los Andes, Bogotá, Colombia; 2Department of Pathology and Immunology, Center for Genome Sciences and Systems Biology, Washington University in Saint Louis, St Louis, MO, USA; 3Max Planck Tandem Group in Computational Biology, Universidad de los Andes, Bogotá, Colombia; 4Department of Parasitology, Institute of Biomedical Sciences, 5Department of Computer Science, Institute of Mathematics and Statistics, Universidade de São Paulo, São Paulo, Brazil Abstract: Sequence similarity searches are the bioinformatic cornerstone of molecular sequence analysis for all domains of life. However, large amounts of divergence between organisms, such as those seen among viruses, can significantly hamper analyses. Profile hidden Markov models (profile HMMs are among the most successful approaches for dealing with this problem, which represent an invaluable tool for viral identification efforts. Profile HMMs are statistical models that convert information from a multiple sequence alignment into a set of probability values that reflect position-specific variation levels in all members of evolutionarily related sequences. Since profile HMMs represent a wide spectrum of variation, these models show higher sensitivity than conventional similarity methods such as BLAST for the detection of remote homologs. In recent years, there has been an effort to compile viral sequences from different viral taxonomic groups into integrated databases, such as Prokaryotic Virus Orthlogous Groups (pVOGs and database of profile HMMs (vFam database, which provide functional annotation, multiple sequence alignments, and profile HMMs. Since these databases rely on viral sequences collected from GenBank and RefSeq, they suffer in variable extent from uneven taxonomic sampling, with low sequence representation of many viral groups, which affects the

Fractal Analysis of Rock Joint Profiles

Science.gov (United States)

Audy, Ondřej; Ficker, Tomáš

2017-10-01

Surface reliefs of rock joints are analyzed in geotechnics when shear strength of rocky slopes is estimated. The rock joint profiles actually are self-affine fractal curves and computations of their fractal dimensions require special methods. Many papers devoted to the fractal properties of these profiles were published in the past but only a few of those papers employed a convenient computational method that would have guaranteed a sound value of that dimension. As a consequence, anomalously low dimensions were presented. This contribution deals with two computational modifications that lead to sound fractal dimensions of the self-affine rock joint profiles. These are the modified box-counting method and the modified yard-stick method sometimes called the compass method. Both these methods are frequently applied to self-similar fractal curves but the self-affine profile curves due to their self-affine nature require modified computational procedures implemented in computer programs.

Magnetic diagnostics: General principles and the problem of reconstruction of plasma current and pressure profiles in toroidal systems

International Nuclear Information System (INIS)

Pustovitov, V.D.

2001-01-01

Restrictions on magnetic diagnostics are discussed. Being related to the integral nature of the measurable quantities, these follow from the fundamental laws of electromagnetism. A series of examples demonstrating the strength of these restrictions is analysed. The general rule is emphasized that information obtained from external magnetic measurements is insufficient for reliable evaluation of plasma current and pressure profiles in tokamaks and in stellarators. The underlying reason is that outside the plasma the self-field of the equilibrium plasma currents is determined by the boundary conditions on the plasma surface alone. (author)

ECH power deposition at 3rd harmonic in high elongation TCV discharges sustained by 2nd harmonic current profile broadening

International Nuclear Information System (INIS)

Pochelon, A. . E-mail : Antoine.Pochelon@epfl.ch; Arnoux, G.; Camenen, Y.

2003-01-01

This paper summarises the present effort aimed at developing high elongation heated discharges and testing their confinement properties at normalised currents for which the highest ideal MHD β-limits are predicted. 2nd harmonic (X2) far off-axis ECH/CD is used to stabilise the plasma vertically at high elongation by broadening the current profile in stationary conditions (during the current flat top and over several current diffusion times). Current broadening is maximal for a power deposition in a narrow region (∼a/5), for a finite toroidal injection angle and for high plasma density using upper lateral launchers to minimise refraction. In these discharges which are twice X2 overdense in the centre, 3rd harmonic (X3) is injected from a top launcher to deposit power in the centre and increase the central pressure, simultaneously with far off-axis X2. Using modulated X3, full absorption is measured by the diamagnetic probe. Absorption higher than calculated by thermal ray tracing is occasionally found, indicating absorption on the electron bulk as well as in the suprathermal electron population sometimes with a hollow deposition profile. The high sensitivity of the power coupling to the beam angle stresses the need for developing a mirror feedback scheme to increase the coupling efficiency in transient heating scenarios. (author)

Sensitivity profiles calculated with the UNISENS system

International Nuclear Information System (INIS)

Claro, L.H.; Menezes, A.

1985-01-01

Sensitivity profiles of the multiplication factor and several central reaction ratios for benchmarks ZPR 6/7, ZPR 3/11, FLATTOP-25, GODIVA and BIG-TEN, are presented in grafic form. A possible utilization is showed throught some modification to the ENDF/B-IV data file proposed for version ENDF/B-V. (Author) [pt

On-current modeling of short-channel double-gate (DG) MOSFETs with a vertical Gaussian-like doping profile

International Nuclear Information System (INIS)

Dubey, Sarvesh; Jit, S.; Tiwari Pramod Kumar

2013-01-01

An analytic drain current model is presented for doped short-channel double-gate MOSFETs with a Gaussian-like doping profile in the vertical direction of the channel. The present model is valid in linear and saturation regions of device operation. The drain current variation with various device parameters has been demonstrated. The model is made more physical by incorporating the channel length modulation effect. Parameters like transconductance and drain conductance that are important in assessing the analog performance of the device have also been formulated. The model results are validated by numerical simulation results obtained by using the commercially available ATLAS™, a two dimensional device simulator from SILVACO. (semiconductor devices)

Surface modification of polyester biomaterials for tissue engineering

International Nuclear Information System (INIS)

Jiao Yanpeng; Cui Fuzhai

2007-01-01

Surfaces play an important role in a biological system for most biological reactions occurring at surfaces and interfaces. The development of biomaterials for tissue engineering is to create perfect surfaces which can provoke specific cellular responses and direct new tissue regeneration. The improvement in biocompatibility of biomaterials for tissue engineering by directed surface modification is an important contribution to biomaterials development. Among many biomaterials used for tissue engineering, polyesters have been well documented for their excellent biodegradability, biocompatibility and nontoxicity. However, poor hydrophilicity and the lack of natural recognition sites on the surface of polyesters have greatly limited their further application in the tissue engineering field. Therefore, how to introduce functional groups or molecules to polyester surfaces, which ideally adjust cell/tissue biological functions, becomes more and more important. In this review, recent advances in polyester surface modification and their applications are reviewed. The development of new technologies or methods used to modify polyester surfaces for developing their biocompatibility is introduced. The results of polyester surface modifications by surface morphological modification, surface chemical group/charge modification, surface biomacromolecule modification and so on are reported in detail. Modified surface properties of polyesters directly related to in vitro/vivo biological performances are presented as well, such as protein adsorption, cell attachment and growth and tissue response. Lastly, the prospect of polyester surface modification is discussed, especially the current conception of biomimetic and molecular recognition. (topical review)

Monitoring the deep western boundary current in the western North Pacific by echo intensity measured with lowered acoustic Doppler current profiler

Science.gov (United States)

Komaki, Kanae; Nagano, Akira

2018-05-01

Oxidation of iron and manganese ions is predominant in the oxygen-rich deep western boundary current (DWBC) within the Pacific Ocean. By the faster removal of particulate iron hydroxide and manganese oxide, densities of the particulate matters are considered to be lower in the DWBC than the interior region. To detect the density variation of suspended particles between the DWBC and interior regions, we analyzed echo intensity (EI) measured in the western North Pacific by hydrographic casts with a 300 kHz lowered acoustic Doppler current profiler (LADCP) in a whole water column. At depths greater than 3000 m ( 3000 dbar), EI is almost uniformly low between 12°N and 30°N but peaks sharply from 30°N to 35°N to a maximum north of 35°N. EI is found to be anomalously low in the DWBC compared to the background distribution. The DWBC pathways are identifiable by the low EI and high dissolved oxygen concentration. EI data by LADCPs and other acoustic instruments may be used to observe the temporal variations of the DWBC pathways.

Modification of Particle Distributions By MHD Instabilities I

International Nuclear Information System (INIS)

White, R.B.

2010-01-01

The modification of particle distributions by low amplitude magnetohydrodynamic modes is an important topic for magnetically confined plasmas. Low amplitude modes are known to be capable of producing significant modification of injected neutral beam profiles, and the same can be expected in burning plasmas for the alpha particle distributions. Flattening of a distribution due to phase mixing in an island or due to portions of phase space becoming stochastic is a process extremely rapid on the time scale of an experiment but still very long compared to the time scale of guiding center simulations. Thus it is very valuable to be able to locate significant resonances and to predict the final particle distribution produced by a given spectrum of magnetohydrodynamic modes. In this paper we introduce a new method of determining domains of phase space in which good surfaces do not exist and use this method for quickly determining the final state of the particle distribution without carrying out the full time evolution leading to it.

Theoretical model of gravitational perturbation of current collector axisymmetric flow field

Science.gov (United States)

Walker, John S.; Brown, Samuel H.; Sondergaard, Neal A.

1990-05-01

Some designs of liquid-metal current collectors in homopolar motors and generators are essentially rotating liquid-metal fluids in cylindrical channels with free surfaces and will, at critical rotational speeds, become unstable. An investigation at David Taylor Research Center is being performed to understand the role of gravity in modifying this ejection instability. Some gravitational effects can be theoretically treated by perturbation techniques on the axisymmetric base flow of the liquid metal. This leads to a modification of previously calculated critical-current-collector ejection values neglecting gravity effects. The purpose of this paper is to document the derivation of the mathematical model which determines the perturbation of the liquid-metal base flow due to gravitational effects. Since gravity is a small force compared with the centrifugal effects, the base flow solutions can be expanded in inverse powers of the Froude number and modified liquid-flow profiles can be determined as a function of the azimuthal angle. This model will be used in later work to theoretically study the effects of gravity on the ejection point of the current collector.

Current regimen of pulse therapy for pemphigus: Minor modifications, improved results

Directory of Open Access Journals (Sweden)

Pasricha J

2008-01-01

Full Text Available Background: If administered properly, dexamethasone cyclophosphamide pulse (DCP therapy has the potential to effect lifelong recovery from pemphigus. Aims: The objective of this paper is to highlight various parameters of DCP therapy and also, to report the effects of a few modifications in the regimen. Methods: An analysis of 123 patients treated with the DCP/DP regimen over a period of five years (1998 to 2002 is presented here. Seventeen patients who did not start/continue the treatment and three patients who died during the treatment have been excluded from the analysis. Twenty patients who had not yet started families were given only dexamethasone pulses (DPs while 103 patients received DCPs. Low dose (50 mg/day cyclophosphamide was used as in the standard regimen. The three modifications introduced into the regimen were: (1 an additional daily dose of oral betamethasone sufficient to control the disease activity during phase I, which was progressively tapered off completely as the patient recovered, (2 use of systemic antibiotics if the patient had skin lesions, and oral anti-candida drugs if the patient had oral ulcers until complete healing, and (3 insistence on thorough cleaning of the skin and scalp with a normal soap and shampoo, and proper maintenance of oral hygiene in spite of skin/mucosal lesions. The regimen consisted of DCP/DP repeated in exactly 28-day cycles, along with 50 mg cyclophosphamide per day, insistence on completing the treatment and avoiding irregular pulses in all patients. The number of DCPs/DPs during phase I varied in different patients depending upon the dose of betamethasone used and the rate of recovery, but phase II (nine DCPs/DPs in exactly 28-day cycles along with 50 mg cyclophosphamide per day and phase III (only 50 mg cyclophosphamide per day was fixed at nine months each. This was followed by posttreatment follow-up (phase IV. Results: At present, all the patients are in complete remission. The

Parameters affecting profile shape of a high energy low current thin ion beam. Vol. 2

Energy Technology Data Exchange (ETDEWEB)

Abdel Salam, F W; Moustafa, O A; El-Khabeary, H [Accelerators Department, Nuclear Research Center, Atomic Energy Authority, Cairo, (Egypt)

1996-03-01

The shape of the profile of a high energy, low current beam of finite length has beam investigated. The beam profile shape depends on the initial beam radius, beam perveance, atomic mass number, charge state of ions, and beam length. These parameters can affect the relation between the initial beam radius and the corresponding final one. An optimum initial beam radius corresponding to minimum final beam at the target has been formulated and the relation between them is deduced taking account of the space charge effect. The minimum beam radius at the target was found to be equal to 2.3 of the optimum initial radius. It is concluded that in order to obtain a small beam radius at a target placed at a finite distance from an ion source, a beam of a low perveance, low atomic mass number and high number of electronic charge is required. This is an important detection for micro machining applications using the oscillating electron ion source which produces nearly paraxial thin beam of low perveance. 12 figs.

Modification of genetic effect of gamma irradiation by electric current

International Nuclear Information System (INIS)

Grigor'eva, N.N.; Shakhbazov, V.G.

1985-01-01

The effect of direct electric current of different value and polarity on genetic sequences of γ-irradiation of Vicia faba seedlings has been studied. The previously found modifying effect of direct electric current is confirmed. The extent and character of this effect depend on the value and polarity of current as well as time between irradiation and electric effects. Current effect modes having no effect on irradiated seedlings protecting cells from injury and the modes aggravating radiation effect have been found. At certain modes the effects of direct electric current on irradiated seedlings changes in the rearrangement spectrum are observed, particularly the number of bridges is increased

Magnetic diagnostics: general principles and the problem of reconstruction of plasma current and pressure profiles in toroidal systems

Energy Technology Data Exchange (ETDEWEB)

Pustovitov, V.D.

2000-04-01

The restrictions of the magnetic diagnostics are discussed. Being related to the integral nature of the measurable quantities, they follow from the fundamental laws of electromagnetism. A series of particular examples demonstrating the strength of these restrictions is given and analyzed. A general rule is emphasized that the information obtained from external magnetic measurements is obviously insufficient for the reliable evaluation of plasma current and pressure profiles in tokamaks or in stellarators. The underlying reason is that outside the plasma the own field of the equilibrium plasma currents is determined by the boundary conditions on the plasma surface only. (author)

Ethanol consumption and pineal melatonin daily profile in rats.

Science.gov (United States)

Peres, Rafael; do Amaral, Fernanda Gaspar; Madrigrano, Thiago Cardoso; Scialfa, Julieta Helena; Bordin, Silvana; Afeche, Solange Castro; Cipolla-Neto, José

2011-10-01

It is well known that melatonin participates in the regulation of many important physiological functions such as sleep-wakefulness cycle, motor coordination and neural plasticity, and cognition. However, as there are contradictory results regarding the melatonin production diurnal profile under alcohol consumption, the aim of this paper was to study the phenomenology and mechanisms of the putative modifications on the daily profile of melatonin production in rats submitted to chronic alcohol intake. The present results show that rats receiving 10% ethanol in drinking water for 35 days display an altered daily profile of melatonin production, with a phase delay and a reduction in the nocturnal peak. This can be partially explained by a loss of the daily rhythm and the 25% reduction in tryptophan hydroxylase activity and, mainly, by a phase delay in arylalkylamine N-acetyltransferase gene expression and a 70% reduction in its peak activity. Upstream in the melatonin synthesis pathway, the results showed that noradrenergic signaling is impaired as well, with a decrease in β1 and α1 adrenergic receptors' mRNA contents and in vitro sustained loss of noradrenergic-stimulated melatonin production by glands from alcohol-treated rats. Together, these results confirm the alterations in the daily melatonin profile of alcoholic rats and suggest the possible mechanisms for the observed melatonin synthesis modification. © 2011 The Authors, Addiction Biology © 2011 Society for the Study of Addiction.

Modification of genetic effect of gamma-irradiation by electric current

International Nuclear Information System (INIS)

Grigor'eva, N.N.; Shakhbazov, V.G.

1983-01-01

The effect of direct current of different polarity on genetic sequels of #betta#-radiation of Vicia faba seedlings is studied. It is established that weak current might modify genetic sequels of #betta#-radiation. Protective current effect on irradiated meristem cells of seedlings manifests at negative polarization of the meristem before radiation and at positive polarization-after radiation. Modifying effect of electric current is brought about at the expense of redistribution of anions and cations between the meristem and other root zones

Acoustic Doppler current profiling from the JGOFS Arabian Sea cruises aboard the RV T.G. Thompson

Energy Technology Data Exchange (ETDEWEB)

Kim, H.S.; Flagg, C.N.; Shi, Y. [Brookhaven National Lab., Upton, NY (United States). Oceanographic and Atmospheric Sciences Div.

1996-12-01

Acoustic Doppler current profiler (ADCP) data is part of the core data for the US JGOFS Arabian Sea project, along with hydrographic and nutrient data. Seventeen cruises are scheduled to take place between September 1994 and January 1996 on the R/V T.G. Thompson. Seven of the cruises follow a standard cruise track, taking hydrographic, chemical and biological measurements. The rest of the cruises, which take place generally within the standard cruise region defined by a set track, are for the deployment and recovery of moored equipment and towing of a SeaSoar. Detailed description of ADCP hardware, the AutoADCP data acquisition system, and the collection of navigation and compass data on the Thompson is documented in Section 2. Followed by data collection for each cruise together with a cruise track, Section 3 presents the processing and analysis of velocity and acoustic backscatter intensity data. Section 5 shows results of profile quality diagnosis.

Use of an Acoustic Doppler Current Profiler (ADCP) to Measure Hypersaline Bidirectional Discharge

Science.gov (United States)

Johnson, K.K.; Loving, B.L.; ,

2002-01-01

The U.S. Geological Survey measures the exchange of flow between the north and south parts of Great Salt Lake, Utah, as part of a monitoring program. Turbidity and bidirectional flow through the breach in the causeway that divides the lake into two parts makes it difficult to measure discharge with conventional streamflow techniques. An acoustic Doppler current profiler (ADCP) can be used to more accurately define the angles of flow and the location of the interface between the layers of flow. Because of the high salinity levels measured in Great Salt Lake (60-280 parts per thousand), special methods had to be developed to adjust ADCP-computed discharges for the increased speed of sound in hypersaline waters and for water entrained at the interface between flow layers.

RNomics and Modomics in the halophilic archaea Haloferax volcanii: identification of RNA modification genes

Directory of Open Access Journals (Sweden)

Decatur Wayne A

2008-10-01

Full Text Available Abstract Background Naturally occurring RNAs contain numerous enzymatically altered nucleosides. Differences in RNA populations (RNomics and pattern of RNA modifications (Modomics depends on the organism analyzed and are two of the criteria that distinguish the three kingdoms of life. If the genomic sequences of the RNA molecules can be derived from whole genome sequence information, the modification profile cannot and requires or direct sequencing of the RNAs or predictive methods base on the presence or absence of the modifications genes. Results By employing a comparative genomics approach, we predicted almost all of the genes coding for the t+rRNA modification enzymes in the mesophilic moderate halophile Haloferax volcanii. These encode both guide RNAs and enzymes. Some are orthologous to previously identified genes in Archaea, Bacteria or in Saccharomyces cerevisiae, but several are original predictions. Conclusion The number of modifications in t+rRNAs in the halophilic archaeon is surprisingly low when compared with other Archaea or Bacteria, particularly the hyperthermophilic organisms. This may result from the specific lifestyle of halophiles that require high intracellular salt concentration for survival. This salt content could allow RNA to maintain its functional structural integrity with fewer modifications. We predict that the few modifications present must be particularly important for decoding, accuracy of translation or are modifications that cannot be functionally replaced by the electrostatic interactions provided by the surrounding salt-ions. This analysis also guides future experimental validation work aiming to complete the understanding of the function of RNA modifications in Archaeal translation.

Temperature profiles and current measurements from the Nathaniel B. Palmer during the 1997 Dovetail cruise in the Southern Ocean (NODC Accession 9900243)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data collection includes temperature profiles from CTD casts and current measurements from hull-mounted ADCP system aboard the research vessel Nathaniel B....

Nanoscale surface modifications to control capillary flow characteristics in PMMA microfluidic devices

Directory of Open Access Journals (Sweden)

Mukhopadhyay Subhadeep

2011-01-01

Full Text Available Abstract Polymethylmethacrylate (PMMA microfluidic devices have been fabricated using a hot embossing technique to incorporate micro-pillar features on the bottom wall of the device which when combined with either a plasma treatment or the coating of a diamond-like carbon (DLC film presents a range of surface modification profiles. Experimental results presented in detail the surface modifications in the form of distinct changes in the static water contact angle across a range from 44.3 to 81.2 when compared to pristine PMMA surfaces. Additionally, capillary flow of water (dyed to aid visualization through the microfluidic devices was recorded and analyzed to provide comparison data between filling time of a microfluidic chamber and surface modification characteristics, including the effects of surface energy and surface roughness on the microfluidic flow. We have experimentally demonstrated that fluid flow and thus filling time for the microfluidic device was significantly faster for the device with surface modifications that resulted in a lower static contact angle, and also that the incorporation of micro-pillars into a fluidic device increases the filling time when compared to comparative devices.

Underling modification in ion beam induced Si wafers

International Nuclear Information System (INIS)

Hazra, S.; Chini, T.K.; Sanyal, M.K.; Grenzer, J.; Pietsch, U.

2005-01-01

Subsurface (amorphous-crystalline interface) structure of keV ion beam modified Si(001) wafers was studied for the first time using non-destructive technique and compared with that of the top one. Ion-beam modifications of the Si samples were done using state-of-art high-current ion implanter facility at Saha Institute of Nuclear Physics by changing energy, dose and angle of incidence of the Ar + ion beam. To bring out the underlying modification depth-resolved x-ray grazing incidence diffraction has been carried out using synchrotron radiation facility, while the structure of the top surface was studied through atomic force microscopy

Comparison of acoustic doppler current profiler and Price AA mechanical current meter measurements made during the 2011 Mississippi River Flood

Science.gov (United States)

O'Brien, Patrick; Mueller, David; Pratt, Thad

2012-01-01

The Mississippi River and Tributaries project performed as designed during the historic 2011 Mississippi River flood, with many of the operational decisions based on discharge targets as opposed to stage. Measurement of discharge at the Tarbert Landing, Mississippi range provides critical information used in operational decisions for the floodways located in Louisiana. Historically, discharge measurements have been made using a Price AA current meter and the mid-section method, and a long record exists based on these types of measurements, including historical peak discharges. Discharge measurements made using an acoustic Doppler current profiler from a moving boat have been incorporated into the record since the mid 1990's, and are used along with the Price AA mid-section measurements. During the 2011 flood event, both methods were used and appeared to provide different results at times. The apparent differences between the measurement techniques are due to complex hydrodynamics at this location that created large spatial and temporal fluctuations in the flow. The data and analysis presented herein show the difference between the two methods to be within the expected accuracy of the measurements when the measurements are made concurrently. The observed fluctuations prevent valid comparisons of data collected sequentially or even with different observation durations.

Direct-current resistivity profiling at the Pecos River Ecosystem Project study site near Mentone, Texas, 2006

Science.gov (United States)

Teeple, Andrew; McDonald, Alyson K.; Payne, Jason; Kress, Wade H.

2009-01-01

The U.S. Geological Survey, in cooperation with Texas A&M University AgriLife, did a surface geophysical investigation at the Pecos River Ecosystem Project study site near Mentone in West Texas intended to determine shallow (to about 14 meters below the water [river] surface) subsurface composition (lithology) in and near treated (eradicated of all saltcedar) and control (untreated) riparian zone sites during June-August 2006. Land-based direct-current resistivity profiling was applied in a 240-meter section of the riverbank at the control site, and waterborne direct-current continuous resistivity profiling (CRP) was applied along a 2.279-kilometer reach of the river adjacent to both sites to collect shallow subsurface resistivity data. Inverse modeling was used to obtain a nonunique estimate of the true subsurface resistivity from apparent resistivity calculated from the field measurements. The land-based survey showed that the sub-surface at the control site generally is of relatively low resis-tivity down to about 4 meters below the water surface. Most of the section from about 4 to 10 meters below the water surface is of relatively high resistivity. The waterborne CRP surveys convey essentially the same electrical representation of the lithology at the control site to 10 meters below the water surface; but the CRP surveys show considerably lower resistivity than the land-based survey in the subsection from about 4 to 10 meters below the water surface. The CRP surveys along the 2.279-kilometer reach of the river adjacent to both the treated and control sites show the same relatively low resistivity zone from the riverbed to about 4 meters below the water surface evident at the control site. A slightly higher resistivity zone is observed from about 4 to 14 meters below the water surface along the upstream approximately one-half of the profile than along the downstream one-half. The variations in resistivity could not be matched to variations in lithology because

Assessment of Design Modifications to Final Clothe the Soldier Rucksack

National Research Council Canada - National Science Library

Reid, S. A; Stevenson, J. M

2006-01-01

.... Quantitative assessment of these functional parameters was undertaken to compare the behaviour of a proposed modification to that of the currently fielded design to ensure no degradation in performance...

EG and G electron linac modifications

International Nuclear Information System (INIS)

Norris, N.J.; Detch, J.L.; Kocimski, S.M.; Sawyer, C.R.; Hudson, C.L.

1986-01-01

A three-year modification of the EG and G electron linac has been performed to replace obsolete equipment and bring all subsystems up to the current state of the art. Components and subsystems were designed, constructed, and tested off-line to minimize interruption of experiments. The configuration of the modified linac is shown schematically, and performance characteristics are give. Each subsystem is described, including: the electron gun; solenoid focusing system; subharmonic bunchers; accelerating system; RF system; klystron modulators and power supplies; control system; beam handling system; vacuum system; and beam current monitors. 7 refs., 4 figs., 2 tabs

Surface modification of TC4 titanium alloy by high current pulsed electron beam (HCPEB) with different pulsed energy densities

International Nuclear Information System (INIS)

Gao, Yu-kui

2013-01-01

Highlights: •The hardness changes were determined by nanoindention method. •The surface integrity changes were investigated by different techniques. •The mechanism was analyzed based on AFM and TEM investigations. -- Abstract: Surface changes including surface topography and nanohardness distribution along surface layer were investigated for TC4 titanium alloy by different energy densities of high current pulsed electron beam (HCPEB). The surface topography was characterized by SEM and AFM, and cross-sectional TEM observation was performed to reveal the surface modification mechanism of TC4 titanium alloy by HCPEB. The surface roughness was modified by HCPEB and the polishing mechanism was analyzed by studying the cross section microstructure of electron beam treated specimens by SEM. The fine grain structure inherited from the rapid solidification of the melted layer as well as the strain hardening of the sub-surface are two of the factors responsible the increase in nanohardness

40 CFR 144.41 - Minor modifications of permits.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Minor modifications of permits. 144.41 Section 144.41 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... responsibility, coverage, and liability between the current and new permittees has been submitted to the Director...

Pulsed Direct Current Electrospray: Enabling Systematic Analysis of Small Volume Sample by Boosting Sample Economy.

Science.gov (United States)

Wei, Zhenwei; Xiong, Xingchuang; Guo, Chengan; Si, Xingyu; Zhao, Yaoyao; He, Muyi; Yang, Chengdui; Xu, Wei; Tang, Fei; Fang, Xiang; Zhang, Sichun; Zhang, Xinrong

2015-11-17

We had developed pulsed direct current electrospray ionization mass spectrometry (pulsed-dc-ESI-MS) for systematically profiling and determining components in small volume sample. Pulsed-dc-ESI utilized constant high voltage to induce the generation of single polarity pulsed electrospray remotely. This method had significantly boosted the sample economy, so as to obtain several minutes MS signal duration from merely picoliter volume sample. The elongated MS signal duration enable us to collect abundant MS(2) information on interested components in a small volume sample for systematical analysis. This method had been successfully applied for single cell metabolomics analysis. We had obtained 2-D profile of metabolites (including exact mass and MS(2) data) from single plant and mammalian cell, concerning 1034 components and 656 components for Allium cepa and HeLa cells, respectively. Further identification had found 162 compounds and 28 different modification groups of 141 saccharides in a single Allium cepa cell, indicating pulsed-dc-ESI a powerful tool for small volume sample systematical analysis.

Magnetic field profiles of NbTi tapes

International Nuclear Information System (INIS)

Migliori, A.; Taylor, R.D.; Bartlett, R.D.

1976-01-01

Magnetic field profile measurements were performed on stabilized NbTi tapes in zero applied field carrying large transport current densities. Field profile data were taken on large diameter superconducting sample loops at temperatures between 2 0 K and T/sub c/ (about 9.2 0 K) and several persistent currents up to I/sub c/(T), the maximum. The field profiles scaled with current, independent of temperature, at temperatures below 8.5 0 K and were well described by an elliptical shell approximation which left a current-free, field-free central region. Critical state models applied to this self-field situation proved inadequate. Complex profiles produced by trapped flux in the tape loop were described quantitatively by assuming concentric elliptical shells each with a different current density. The maximum current which could be persisted in the loop at each temperature was linear from 4 to 8.5 K. The effective resistance of the superconducting loop including its joint was less than 10 -13 ohms

Neoclassical MHD equilibria with ohmic current

International Nuclear Information System (INIS)

Tokuda, Shinji; Takeda, Tatsuoki; Okamoto, Masao.

1989-01-01

MHD equilibria of tokamak plasmas with neoclassical current effects (neoclassical conductivity and bootstrap current) were calculated self-consistently. Neoclassical effects on JFT-2M tokamak plasmas, sustained by ohmic currents, were studied. Bootstrap currents flow little for L-mode type equilibria because of low attainable values of poloidal beta, β J . H-mode type equilibria give bootstrap currents of 30% ohmic currents for β J attained by JFT-2M and 100% for β J ≥ 1.5, both of which are sufficient to change the current profiles and the resultant MHD equilibria. Neoclassical conductivity which has roughly half value of the classical Spitzer conductivity brings peaked ohmic current profiles to yield low safety factor at the magnetic axis. Neoclassical conductivity reduces the value of effective Z(Z eff ) which is necessary to give the observed one-turn voltage but it needs impurities accumulating at the center when such peaked current profiles are not observed. (author)

Causal dissipation and shock profiles in the relativistic fluid dynamics of pure radiation.

Science.gov (United States)

Freistühler, Heinrich; Temple, Blake

2014-06-08

CURRENT THEORIES OF DISSIPATION IN THE RELATIVISTIC REGIME SUFFER FROM ONE OF TWO DEFICITS: either their dissipation is not causal or no profiles for strong shock waves exist. This paper proposes a relativistic Navier-Stokes-Fourier-type viscosity and heat conduction tensor such that the resulting second-order system of partial differential equations for the fluid dynamics of pure radiation is symmetric hyperbolic. This system has causal dissipation as well as the property that all shock waves of arbitrary strength have smooth profiles. Entropy production is positive both on gradients near those of solutions to the dissipation-free equations and on gradients of shock profiles. This shows that the new dissipation stress tensor complies to leading order with the principles of thermodynamics. Whether higher order modifications of the ansatz are required to obtain full compatibility with the second law far from the zero-dissipation equilibrium is left to further investigations. The system has exactly three a priori free parameters χ , η , ζ , corresponding physically to heat conductivity, shear viscosity and bulk viscosity. If the bulk viscosity is zero (as is stated in the literature) and the total stress-energy tensor is trace free, the entire viscosity and heat conduction tensor is determined to within a constant factor.

Current, profile, and other data from current meters and CTD casts from NOAA Ship DISCOVERER and other platforms from the NW Pacific (limit-180) as part of the VENTS program from 1991-06-11 to 1992-06-11 (NODC Accession 9300078)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Current, profile, and other data were collected from current meters and CTD casts from NOAA Ship Discoverer and other platforms from the NW Pacific (limit-180) from...

Modification of membrane sulfhydryl groups in bacteriostatic action of nitrite

International Nuclear Information System (INIS)

Buchman, G.W. III; Hansen, J.N.

1987-01-01

The mechanism by which nitrite inhibits outgrowing spores of bacillus cereus T was examined by using techniques developed earlier for nitrite analogs. The morphological stage of inhibition, cooperativity effects, effect of pH on inhibition, kinetics of protection against tritiated iodoacetate incorporation into membrane sulfhydryl groups, and protection against the bacteriocidal effect of carboxymethylation of iodoacetate indicate that nitrite acts as a membrane-directed sulfhydryl agent. The mechanism by which nitrite modifies the chemical reactivity of the sulfhyrdyl group could be either direct covalent modification or inactivation through communication with another modified membrane component. Profiles of pH effects suggest that the active agent is the protonated form of nitrite. The nitrite concentrations which modify membrane sulfhydryl activity coincide with those which have a bacteriostatic effect. These results are consistent with membrane sulfhydryl modification as a component of the mechanism of nitrite-induced bacteriostasis in this aerobic sporeformer

Comparison of proteomic and transcriptomic profiles in the bronchial airway epithelium of current and never smokers.

Directory of Open Access Journals (Sweden)

Katrina Steiling

Full Text Available Although prior studies have demonstrated a smoking-induced field of molecular injury throughout the lung and airway, the impact of smoking on the airway epithelial proteome and its relationship to smoking-related changes in the airway transcriptome are unclear.Airway epithelial cells were obtained from never (n = 5 and current (n = 5 smokers by brushing the mainstem bronchus. Proteins were separated by one dimensional polyacrylamide gel electrophoresis (1D-PAGE. After in-gel digestion, tryptic peptides were processed via liquid chromatography/ tandem mass spectrometry (LC-MS/MS and proteins identified. RNA from the same samples was hybridized to HG-U133A microarrays. Protein detection was compared to RNA expression in the current study and a previously published airway dataset. The functional properties of many of the 197 proteins detected in a majority of never smokers were similar to those observed in the never smoker airway transcriptome. LC-MS/MS identified 23 proteins that differed between never and current smokers. Western blotting confirmed the smoking-related changes of PLUNC, P4HB1, and uteroglobin protein levels. Many of the proteins differentially detected between never and current smokers were also altered at the level of gene expression in this cohort and the prior airway transcriptome study. There was a strong association between protein detection and expression of its corresponding transcript within the same sample, with 86% of the proteins detected by LC-MS/MS having a detectable corresponding probeset by microarray in the same sample. Forty-one proteins identified by LC-MS/MS lacked detectable expression of a corresponding transcript and were detected in profiled the airway epithelium proteome and identified proteins expressed at different levels as a result of cigarette smoke exposure. While there was a strong correlation

Effects of centrifugal modification of magnetohydrodynamic equilibrium on resistive wall mode stability

International Nuclear Information System (INIS)

Shiraishi, J.; Aiba, N.; Miyato, N.; Yagi, M.

2014-01-01

Toroidal rotation effects are self-consistently taken into account not only in the linear magnetohydrodynamic (MHD) stability analysis but also in the equilibrium calculation. The MHD equilibrium computation is affected by centrifugal force due to the toroidal rotation. To study the toroidal rotation effects on resistive wall modes (RWMs), a new code has been developed. The RWMaC modules, which solve the electromagnetic dynamics in vacuum and the resistive wall, have been implemented in the MINERVA code, which solves the Frieman–Rotenberg equation that describes the linear ideal MHD dynamics in a rotating plasma. It is shown that modification of MHD equilibrium by the centrifugal force significantly reduces growth rates of RWMs with fast rotation in the order of M 2  = 0.1 where M is the Mach number. Moreover, it can open a stable window which does not exist under the assumption that the rotation affects only the linear dynamics. The rotation modifies the equilibrium pressure gradient and current density profiles, which results in the change of potential energy including rotational effects. (paper)

Fundamental aspects on ion-beam surface modification: defect production and migration processes

International Nuclear Information System (INIS)

Rehn, L.E.; Averback, R.S.; Okamoto, P.R.

1984-09-01

Ion-beam modification of metals is generating increasing scientific interest not only because it has exciting technological potential, but also because it has raised fundamental questions concerning radiation-induced diffusion processes. In addition to the implanted species, several defect production and migration mechanisms contribute to changes in the near-surface composition of an alloy during ion bombardment, e.g., atoms exchange positions via displacements and replacement sequences; preferential sputtering effects arise; radiation-enhanced diffusion and radiation-induced segregation occur. The latter two defect migration mechanisms are of particular significance since they can alter the composition to depths which are much greater than the implanted ion range. By altering various parameters such as irradiation temperature, ion mass, energy, and current density, and initial alloying distributions, a rich variety of near-surface composition profiles can be created. We have utilized changes in ion mass and energy, and irradiation temperature to distinguish defect production from defect migration effects. Experimental results are presented which provide a guide to the relative efficiencies of different mechanisms under various irradiation conditions. 46 references

Internet-based cognitive bias modification for obsessive compulsive disorder : study protocol for a randomized controlled trial

NARCIS (Netherlands)

Williams, Alishia D; Pajak, Rosanna; O'Moore, Kathleen; Andrews, Gavin; Grisham, Jessica R

2014-01-01

BACKGROUND: Cognitive bias modification (CBM) interventions have demonstrated efficacy in augmenting core biases implicated in psychopathology. The current randomized controlled trial (RCT) will evaluate the efficacy of an internet-delivered positive imagery cognitive bias modification intervention

Role of Oxidative Stress in Epigenetic Modification in Endometriosis.

Science.gov (United States)

Ito, Fuminori; Yamada, Yuki; Shigemitsu, Aiko; Akinishi, Mika; Kaniwa, Hiroko; Miyake, Ryuta; Yamanaka, Shoichiro; Kobayashi, Hiroshi

2017-11-01

Aberrant DNA methylation and histone modification are associated with an increased risk of reproductive disorders such as endometriosis. However, a cause-effect relationship between epigenetic mechanisms and endometriosis development has not been fully determined. This review provides current information based on oxidative stress in epigenetic modification in endometriosis. This article reviews the English-language literature on epigenetics, DNA methylation, histone modification, and oxidative stress associated with endometriosis in an effort to identify epigenetic modification that causes a predisposition to endometriosis. Oxidative stress, secondary to the influx of hemoglobin, heme, and iron during retrograde menstruation, is involved in the expression of CpG demethylases, ten-eleven translocation, and jumonji (JMJ). Ten-eleven translocation and JMJ recognize a wide range of endogenous DNA methyltransferases (DNMTs). The increased expression levels of DNMTs may be involved in the subsequent downregulation of the decidualization-related genes. This review supports the hypothesis that there are at least 2 distinct phases of epigenetic modification in endometriosis: the initial wave of iron-induced oxidative stress would be followed by the second big wave of epigenetic modulation of endometriosis susceptibility genes. We summarize the recent advances in our understanding of the underlying epigenetic mechanisms focusing on oxidative stress in endometriosis.

Current pharmacotherapies for obesity: A practical perspective.

Science.gov (United States)

Golden, Angela

2017-10-01

To review the currently available pharmacotherapies for obesity management with a particular focus on the United States. Narrative review based on literature searches and the latest prescribing information (up to July 2017). Obesity pharmacotherapies may assist those individuals who have obesity, or overweight with comorbidities, who have failed to maintain weight loss with lifestyle modifications alone (caloric restriction and increased physical activity). Currently approved options in the United States include phentermine for short-term use and five obesity pharmacotherapies that can be used long-term (orlistat, lorcaserin, phentermine-topiramate, naltrexone-bupropion, and liraglutide 3.0 mg). If the use of an obesity pharmacotherapy is indicated, treatment should be selected to provide the most appropriate option for each individual and their circumstances. Variables such as contraindications, individual comorbidities, patient choice, patient readiness to incorporate additional behavioral changes (e.g., alcohol prohibition), and cost should guide choices. Each of the obesity pharmacotherapies has advantages and disadvantages that can help guide treatment choice. Those receiving treatment may also have individual preferences based on factors such as administration route, frequency of dosing, and/or safety profile. In addition, some options may be particularly appropriate for patients with common obesity-related complications such as depression or diabetes. ©2017 American Association of Nurse Practitioners.

Quantitative proteomic characterization of redox-dependent post-translational modifications on protein cysteines

Energy Technology Data Exchange (ETDEWEB)

Duan, Jicheng; Gaffrey, Matthew J.; Qian, Wei-Jun

2017-01-01

Protein cysteine thiols play a crucial role in redox signaling, regulation of enzymatic activity and protein function, and maintaining redox homeostasis in living systems. The unique chemical reactivity of thiol groups makes cysteine susceptible to oxidative modifications by reactive oxygen and nitrogen species to form a broad array of reversible and irreversible protein post-translational modifications (PTMs). The reversible modifications in particular are one of the major components of redox signaling and are involved in regulation of various cellular processes under physiological and pathological conditions. The biological significance of these redox PTMs in health and diseases has been increasingly recognized. Herein, we review the recent advances of quantitative proteomic approaches for investigating redox PTMs in complex biological systems, including the general considerations of sample processing, various chemical or affinity enrichment strategies, and quantitative approaches. We also highlight a number of redox proteomic approaches that enable effective profiling of redox PTMs for addressing specific biological questions. Although some technological limitations remain, redox proteomics is paving the way towards a better understanding of redox signaling and regulation in human health and diseases.

Modifications to nuclear power plants. Safety guide

International Nuclear Information System (INIS)

2004-01-01

This Safety Guide was prepared under the IAEA's programme for safety standards for nuclear power plants. It supplements Section 7 of the Safety Requirements publication on Safety of Nuclear Power Plants: Operation, which establishes the safety requirements for the modification of nuclear power plants. Reasons for carrying out modifications to nuclear power plants may include: (1) maintaining or strengthening existing safety provisions and thus maintaining consistency with or improving on the current design. (2) recovering from plant faults. (3) improving the thermal performance or increasing the power rating of the plant. (4) increasing the maintainability of the plant, reducing the radiation exposure of personnel or reducing the costs of plant maintenance. And (5) extending the design life of the plant. Most modifications, made on the basis of operating experience, are intended to improve on the design or to improve operational performance and flexibility. Some are rendered necessary by new regulatory requirements, ageing of the plant or obsolescence of equipment. However, the benefits of regularly updating the plant design can be jeopardized if modifications are not kept under rigorous control throughout the lifetime of the plant. The need to reduce costs and improve efficiency, in combination with changes to the structure of the electricity generation sector of the economy in many countries, has led many companies to make changes in the structure of the operating organization for nuclear power plants. Whatever the reason for such organizational changes, consideration should be given to the effects of those changes with the aim of ensuring that they would have no impacts that would compromise the safety of the plant. The objective of this Safety Guide is to provide guidance and recommendations on controlling activities relating to modifications at nuclear power plants in order to reduce risk and to ensure that the configuration of the plant is at all times under

Modifications to nuclear power plants. Safety guide

International Nuclear Information System (INIS)

2007-01-01

This Safety Guide was prepared under the IAEA's programme for safety standards for nuclear power plants. It supplements Section 7 of the Safety Requirements publication on Safety of Nuclear Power Plants: Operation, which establishes the safety requirements for the modification of nuclear power plants. Reasons for carrying out modifications to nuclear power plants may include: (1) maintaining or strengthening existing safety provisions and thus maintaining consistency with or improving on the current design. (2) recovering from plant faults. (3) improving the thermal performance or increasing the power rating of the plant. (4) increasing the maintainability of the plant, reducing the radiation exposure of personnel or reducing the costs of plant maintenance. And (5) extending the design life of the plant. Most modifications, made on the basis of operating experience, are intended to improve on the design or to improve operational performance and flexibility. Some are rendered necessary by new regulatory requirements, ageing of the plant or obsolescence of equipment. However, the benefits of regularly updating the plant design can be jeopardized if modifications are not kept under rigorous control throughout the lifetime of the plant. The need to reduce costs and improve efficiency, in combination with changes to the structure of the electricity generation sector of the economy in many countries, has led many companies to make changes in the structure of the operating organization for nuclear power plants. Whatever the reason for such organizational changes, consideration should be given to the effects of those changes with the aim of ensuring that they would have no impacts that would compromise the safety of the plant. The objective of this Safety Guide is to provide guidance and recommendations on controlling activities relating to modifications at nuclear power plants in order to reduce risk and to ensure that the configuration of the plant is at all times under

Effects of controlled school-based multi-component model of nutrition and lifestyle interventions on behavior modification, anthropometry and metabolic risk profile of urban Asian Indian adolescents in North India.

Science.gov (United States)

Singhal, N; Misra, A; Shah, P; Gulati, S

2010-04-01

To study the effectiveness of a multi-component intervention model of nutrition and lifestyle education on behavior modification, anthropometry and metabolic risk profile of urban Asian-Indian adolescents in North India. Two schools matched for student strength and middle socioeconomic strata were randomly allocated to intervention and control group. Changes in nutrition-related knowledge, attitude, lifestyle practices, food frequency and body image of eleventh-grade students (15-17 years) in both schools were tested using a validated questionnaire. Anthropometric and biochemical measurements were made using standard methods. Segmental body composition analysis was carried out using an 8-electrode multifrequency bioelectrical impedance method of body fat estimation. At 6 months follow-up, significant improvement in several domains of knowledge was observed in intervention children (n=99; males=60; females=39) as compared with control school children (n=102; males=61; females=41). In the intervention group, significantly lower proportion of children consumed aerated drinks (15.1%; Phabits and lifestyle practices, and resulted in beneficial changes in anthropometric and biochemical profiles of the Asian Indian adolescents. This model should be applied on countrywide basis to prevent obesity and diabetes.

Predictions of fast wave heating, current drive, and current drive antenna arrays for advanced tokamaks

International Nuclear Information System (INIS)

Batchelor, D.B.; Baity, F.W.; Carter, M.D.

1994-01-01

The objective of the advanced tokamak program is to optimize plasma performance leading to a compact tokamak reactor through active, steady state control of the current profile using non-inductive current drive and profile control. To achieve these objectives requires compatibility and flexibility in the use of available heating and current drive systems--ion cyclotron radio frequency (ICRF), neutral beams, and lower hybrid. For any advanced tokamak, the following are important challenges to effective use of fast waves in various roles of direct electron heating, minority ion heating, and current drive: (1) to employ the heating and current drive systems to give self-consistent pressure and current profiles leading to the desired advanced tokamak operating modes; (2) to minimize absorption of the fast waves by parasitic resonances, which limit current drive; (3) to optimize and control the spectrum of fast waves launched by the antenna array for the required mix of simultaneous heating and current drive. The authors have addressed these issues using theoretical and computational tools developed at a number of institutions by benchmarking the computations against available experimental data and applying them to the specific case of TPX

40 CFR 122.63 - Minor modifications of permits.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Minor modifications of permits. 122.63..., coverage, and liability between the current and new permittees has been submitted to the Director. (e)(1...) Incorporate changes to the terms of a CAFO's nutrient management plan that have been revised in accordance...

Monitoring of the current profile by using cyclotronic electron waves in tokamaks; Controle du profil de courant par ondes cyclotroniques electroniques dans les tokamaks

Energy Technology Data Exchange (ETDEWEB)

Dumont, R

2001-08-01

The subject of this thesis is the study of the cyclotronic electron wave as a monitoring tool of the current profile. The first chapter is dedicated to basic notions concerning tokamak plasmas and current generation. The second chapter is centered on the use of fast electrons to generate current and on its modelling. The propagation and absorption of the cyclotronic electron wave require a specific polarization state whose characteristics must be carefully chosen according to some parameters of the discharge, the chapter 3 deals with this topic. The absorption of a wave in a plasma depends greatly on the velocity distribution of the particles that make up the plasma and this distribution is constantly modified by the energy of the wave, so this phenomenon is non-linear and its physical description is difficult. In a case of a fusion plasma, a sophisticated approximation called quasi-linear theory can be applied with some restrictions that are presented in chapter 4. Chapters 5 and 6 are dedicated to kinetics scenarios involving the low hybrid wave and the cyclotronic electron wave inside the plasma. Some experiments dedicated to the study of the cyclotronic electron wave have been performed in Tore-supra (France) and FTU (Italy) tokamaks, they are presented in the last chapter. (A.C.)

Fast current ramp experiments on TFTR

International Nuclear Information System (INIS)

Fredrickson, E.D.; McGuire, K.; Goldston, R.J.

1987-05-01

Electron heat transport on TFTR and other tokamaks is several orders of magnitude larger than neoclassical calculations would predict. Despite considerable effort, there is still no clear theoretical understanding of this anomalous transport. The electron temperature profile T/sub e/(r), shape has shown a marked consistency on many machines, including TFTR, for a wide range of plasma parameters and heating profiles. This could be an important clue as to the process responsible for this enhanced thermal transport. In this paper 'profile consistency' in TFTR is described and an experiment which uses a fast current ramp to transiently decouple the current density profile J(r), and the T/sub e/(r) profiles is discussed. From this experiment the influence of J(r) on electron temperature profile consistency can be determined

Role of turbulence fluctuations on uncertainties of acoutic Doppler current profiler discharge measurements

Science.gov (United States)

Tarrab, Leticia; Garcia, Carlos M.; Cantero, Mariano I.; Oberg, Kevin

2012-01-01

This work presents a systematic analysis quantifying the role of the presence of turbulence fluctuations on uncertainties (random errors) of acoustic Doppler current profiler (ADCP) discharge measurements from moving platforms. Data sets of three-dimensional flow velocities with high temporal and spatial resolution were generated from direct numerical simulation (DNS) of turbulent open channel flow. Dimensionless functions relating parameters quantifying the uncertainty in discharge measurements due to flow turbulence (relative variance and relative maximum random error) to sampling configuration were developed from the DNS simulations and then validated with field-scale discharge measurements. The validated functions were used to evaluate the role of the presence of flow turbulence fluctuations on uncertainties in ADCP discharge measurements. The results of this work indicate that random errors due to the flow turbulence are significant when: (a) a low number of transects is used for a discharge measurement, and (b) measurements are made in shallow rivers using high boat velocity (short time for the boat to cross a flow turbulence structure).

Surface modification of yttria stabilized zirconia by ion implantation

International Nuclear Information System (INIS)

Scholten, D.

1987-01-01

The results of investigations of surface modification by ion implantation in zirconia are described. As dopant material, iron was investigated thoroughly. The depth distribution of implanted ions depends on implantation parameters and the dopant-matrix system. The investigations of thermal stability of some implanted iron profiles by RBS and AES are described. Special interest lies in the thermal stability under working conditions of the zirconia material (400-1000 0 C). Radiation damage introduced in the implanted layer was investigated using transmission electron microscopy on polycrystalline material and channeling experiments on a single crystal implanted with iron. 179 refs.; 87 figs.; 20 tabs

O-GlcNAc profiling: from proteins to proteomes

Science.gov (United States)

2014-01-01

O-linked β-D-N-acetylglucosamine (O-GlcNAc) modification (O-GlcNAcylation) onto serine and threonine residues of proteins is an important post-translational modification (PTM), which is involved in many crucial biological processes including transcription, translation, proteasomal degradation, and signal transduction. Aberrant protein O-GlcNAcylation is directly linked to the pathological progression of chronic diseases including diabetes, cancer, and neurodegenerative disorders. Identification, site mapping, and quantification of O-GlcNAc proteins are a prerequisite to decipher their functions. In this review, we mainly focus on technological developments regarding O-GlcNAc protein profiling. Specifically, on one hand, we show how these techniques are being used for the comprehensive characterization of certain targeted proteins in which biologists are most interested. On the other hand, we present several newly developed approaches for O-GlcNAcomic profiling as well as how they provide us with a systems perspective to crosstalk amongst different PTMs and complicated biological events. Promising technical trends are also highlighted to evoke more efforts by diverse laboratories, which would further expand our understanding of the physiological and pathological roles of protein O-GlcNAcylation in chronic diseases. PMID:24593906

Bipolar transurethral resection of the prostate - technical modifications and early clinical experience

NARCIS (Netherlands)

Rassweiler, Jens; Schulze, Michael; Stock, Christian; Teber, Dogu; de la Rosette, Jean

2007-01-01

The purpose of the study was to update the current modifications of transurethral resection of the prostate (TURP) using bipolar high frequency current and to report on our first own clinical experience. Based on a Medline search covering the period from January 2000 to September 2006 and our

Peptidomics of Peptic Digest of Selected Potato Tuber Proteins: Post-Translational Modifications and Limited Cleavage Specificity.

Science.gov (United States)

C K Rajendran, Subin R; Mason, Beth; Udenigwe, Chibuike C

2016-03-23

Bioinformatic tools are useful in predicting bioactive peptides from food proteins. This study was focused on using bioinformatics and peptidomics to evaluate the specificity of peptide release and post-translational modifications (PTMs) in a peptic digest of potato protein isolate. Peptides in the protein hydrolysate were identified by LC-MS/MS and subsequently aligned to their parent potato tuber proteins. Five major proteins were selected for further analysis, namely, lipoxygenase, α-1,4-glucan phosphorylase, annexin, patatin, and polyubiquitin, based on protein coverage, abundance, confidence levels, and function. Comparison of the in silico peptide profile generated with ExPASy PeptideCutter and experimental peptidomics data revealed several differences. The experimental peptic cleavage sites were found to vary in number and specificity from PeptideCutter predictions. Average peptide chain length was also found to be higher than predicted with hexapeptides as the smallest detected peptides. Moreover, PTMs, particularly Met oxidation and Glu/Asp deamidation, were observed in some peptides, and these were unaccounted for during in silico analysis. PTMs can be formed during aging of potato tubers, or as a result of processing conditions during protein isolation and hydrolysis. The findings provide insights on the limitations of current bioinformatics tools for predicting bioactive peptide release from proteins, and on the existence of structural modifications that can alter the peptide bioactivity and functionality.

Effects of Harbor Modification on Crescent City, California's Tsunami Vulnerability

Science.gov (United States)

Dengler, Lori; Uslu, Burak

2011-06-01

More damaging tsunamis have impacted Crescent City, California in historic times than any other location on the West Coast of the USA. Crescent City's harbor has undergone significant modification since the early 20th century, including construction of several breakwaters, dredging, and a 200 × 300 m2 small boat basin. In 2006, a M w 8.3 earthquake in the Kuril Islands generated a moderate Pacific-wide tsunami. Crescent City recorded the highest amplitudes of any tide gauge in the Pacific and was the only location to experience structural damage. Strong currents damaged docks and boats within the small boat basin, causing more than US 20 million in damage and replacement costs. We examine how modifications to Crescent City's harbor may have affected its vulnerability to moderate tsunamis such as the 2006 event. A bathymetric grid of the basin was constructed based on US Army Corps of Engineers soundings in 1964 and 1965 before the construction of the small boat basin. The method of splitting tsunamis was used to estimate tsunami water heights and current velocities at several locations in the harbor using both the 1964-1965 grid and the 2006 bathymetric grid for the 2006 Kuril event and a similar-sized source along the Sanriku coast of Japan. Model velocity outputs are compared for the two different bathymetries at the tide gauge location and at six additional computational sites in the harbor. The largest difference between the two grids is at the small boat basin entrance, where the 2006 bathymetry produces currents over three times the strength of the currents produced by the 1965 bathymetry. Peak currents from a Sanriku event are comparable to those produced by the 2006 event, and within the boat basin may have been higher. The modifications of the harbor, and in particular the addition of the small boat basin, appear to have contributed to the high current velocities and resulting damage in 2006 and help to explain why the 1933 M w 8.4-8.7 Sanriku tsunami

In vitro profiling of epigenetic modifications underlying heavy metal toxicity of tungsten-alloy and its components

International Nuclear Information System (INIS)

Verma, Ranjana; Xu, Xiufen; Jaiswal, Manoj K.; Olsen, Cara; Mears, David; Caretti, Giuseppina; Galdzicki, Zygmunt

2011-01-01

Tungsten-alloy has carcinogenic potential as demonstrated by cancer development in rats with intramuscular implanted tungsten-alloy pellets. This suggests a potential involvement of epigenetic events previously implicated as environmental triggers of cancer. Here, we tested metal induced cytotoxicity and epigenetic modifications including H3 acetylation, H3-Ser10 phosphorylation and H3-K4 trimethylation. We exposed human embryonic kidney (HEK293), human neuroepithelioma (SKNMC), and mouse myoblast (C2C12) cultures for 1-day and hippocampal primary neuronal cultures for 1-week to 50-200 μg/ml of tungsten-alloy (91% tungsten/6% nickel/3% cobalt), tungsten, nickel, and cobalt. We also examined the potential role of intracellular calcium in metal mediated histone modifications by addition of calcium channel blockers/chelators to the metal solutions. Tungsten and its alloy showed cytotoxicity at concentrations > 50 μg/ml, while we found significant toxicity with cobalt and nickel for most tested concentrations. Diverse cell-specific toxic effects were observed, with C2C12 being relatively resistant to tungsten-alloy mediated toxic impact. Tungsten-alloy, but not tungsten, caused almost complete dephosphorylation of H3-Ser10 in C2C12 and hippocampal primary neuronal cultures with H3-hypoacetylation in C2C12. Dramatic H3-Ser10 dephosphorylation was found in all cobalt treated cultures with a decrease in H3 pan-acetylation in C2C12, SKNMC and HEK293. Trimethylation of H3-K4 was not affected. Both tungsten-alloy and cobalt mediated H3-Ser10 dephosphorylation were reversed with BAPTA-AM, highlighting the role of intracellular calcium, confirmed with 2-photon calcium imaging. In summary, our results for the first time reveal epigenetic modifications triggered by tungsten-alloy exposure in C2C12 and hippocampal primary neuronal cultures suggesting the underlying synergistic effects of tungsten, nickel and cobalt mediated by changes in intracellular calcium homeostasis and

X-ray photoelectron spectroscopic depth profilometry of nitrogen implanted in materials for modification of their surface properties

International Nuclear Information System (INIS)

Sarkissian, A.H.; Paynter, R.; Stansfield, B.L.

1996-01-01

The modification of the surface properties of materials has a wide range of industrial applications. For example, the authors change the electrical characteristics of semiconductors, improve surface hardness, decrease friction, increase resistance to corrosion, improve adhesion, etc. Nitriding is one of the most common processes used in industry for surface treatment. Nitrogen ion implantation is one technique often used to achieve this goal. Ion implantation offers the power to control the deposition profile, and can be achieved by either conventional ion beam implantation or plasma assisted ion implantation. They have used the technique of plasma assisted ion implantation to implant nitrogen in several materials, including titanium, silicon and stainless steel. The plasma source is a surface ECR source developed at INRS-Energie et Materiaux. The depth profile of the implanted ions has been measured by X-ray photoelectron spectroscopy. They have also conducted simulations using the TRIM-95 code to predict the depth profile of the implanted ions. Comparisons of the measured results with those from simulations are used to deduce information regarding the plasma composition and the collisional effects in the plasma. A fast responding, current and voltage measuring circuit with fiber optic links is being developed, which allows more accurate quantitative measurements. Further experiments to study the characteristics of the plasma, and their effects on the characteristics of the implanted surfaces are in progress, and the results are presented at this meeting

Predictions of of fast wave heating, current drive, and current drive antenna arrays for advanced tokamaks

International Nuclear Information System (INIS)

Batchelor, D.B.; Baity, F.W.; Carter, M.D.

1995-01-01

The objective of the advanced tokamak program is to optimize plasma performance leading to a compact tokamak reactor through active, steady state control of the current profile using non-inductive current drive and profile control. To achieve this objective requires compatibility and flexibility in the use of available heating and current drive systems - ion cyclotron radio frequency (ICRF), neutral beams, and lower hybrid. For any advanced tokamak, the following are important challenges to effective use of fast waves in various role of direct electron heating, minority ion heating, and current drive: (1) to employ the heating and current drive systems to give self-consistent pressure and current profiles leading to the desired advanced tokamak operating modes; (2) to minimize absorption of the fast waves by parasitic resonances, which limit current drive; (3) to optimize and control the spectrum of fast waves launched by the antenna array for the required mix of simultaneous heating and current drive. The paper addresses these issues using theoretical and computational tools developed at a number of institutions by benchmarking the computations against available experimental data and applying them to the specific case of TPX. (author). 6 refs, 3 figs

76 FR 57681 - Modification of Interlibrary Loan Fee Schedule

Science.gov (United States)

2011-09-16

... through the National Technical Information Service (NTIS) or payment through the Online Computer Library... in order to support the current cost of providing the service and will enable customers to estimate... Service 7 CFR Part 505 RIN 0518-8AA04 Modification of Interlibrary Loan Fee Schedule AGENCY: Agricultural...

Basic principle of constant q/sub a/ current build-up in tokamaks

International Nuclear Information System (INIS)

Kikuchi, M.

1985-05-01

An analytic expression is derived such that the current profile shape is kept constant during the current build-up phase in tokamaks. The required conductivity profile is parametrized by two externally controllable parameters, I/sub p/ and a/sub p/ in the case of the Gaussian current profile. It is shown that a Gaussian current profile can be maintained for a realistically broad conductivity profile by using the constant q/sub a/ current build-up method even under the condition of a high I/sub p/

Site-selective protein-modification chemistry for basic biology and drug development.

Science.gov (United States)

Krall, Nikolaus; da Cruz, Filipa P; Boutureira, Omar; Bernardes, Gonçalo J L

2016-02-01

Nature has produced intricate machinery to covalently diversify the structure of proteins after their synthesis in the ribosome. In an attempt to mimic nature, chemists have developed a large set of reactions that enable post-expression modification of proteins at pre-determined sites. These reactions are now used to selectively install particular modifications on proteins for many biological and therapeutic applications. For example, they provide an opportunity to install post-translational modifications on proteins to determine their exact biological roles. Labelling of proteins in live cells with fluorescent dyes allows protein uptake and intracellular trafficking to be tracked and also enables physiological parameters to be measured optically. Through the conjugation of potent cytotoxicants to antibodies, novel anti-cancer drugs with improved efficacy and reduced side effects may be obtained. In this Perspective, we highlight the most exciting current and future applications of chemical site-selective protein modification and consider which hurdles still need to be overcome for more widespread use.

Issues in neutral currents

International Nuclear Information System (INIS)

Sehgal, L.M.

1980-01-01

The experimental results on low energy confirming the structure of the effective Lagrangian of the weak neutral current processes as predicted by the Salam-Weinberg model are reviewed. Some possible modifications of the effective Lagrangian and the feasibility of their experimental verification are also considered. (P.L.)

Fabrication and surface-modification of implantable microprobes for neuroscience studies

International Nuclear Information System (INIS)

Cao, H; Nguyen, C M; Chiao, J C

2012-01-01

In this work implantable micro-probes for central nervous system (CNS) studies were developed on silicon and polyimide substrates. The probes which contained micro-electrode arrays with different surface modifications were designed for implantation in the CNS. The electrode surfaces were modified with nano-scale structures that could greatly increase the active surface area in order to enhance the electrochemical current outputs while maintaining micro-scale dimensions of the electrodes and probes. The electrodes were made of gold or platinum, and designed with different sizes. The silicon probes were modified by silicon nanowires fabricated with the vapor–liquid–solid mechanism at high temperatures. With polyimide substrates, the nanostructure modification was carried out by applying concentrated gold or silver colloid solutions onto the micro-electrodes at room temperature. The surfaces of electrodes before and after modification were observed by scanning electron microscopy. The silicon nanowire-modified surface was characterized by cyclic voltammetry. Experiments were carried out to investigate the improvement in sensing performance. The modified electrodes were tested with H 2 O 2 , electrochemical L-glutamate and dopamine. Comparisons between electrodes with and without nanostructure modification were conducted showing that the modifications have enhanced the signal outputs of the electrochemical neurotransmitter sensors

Fabrication and surface-modification of implantable microprobes for neuroscience studies

Science.gov (United States)

Cao, H.; Nguyen, C. M.; Chiao, J. C.

2012-06-01

In this work implantable micro-probes for central nervous system (CNS) studies were developed on silicon and polyimide substrates. The probes which contained micro-electrode arrays with different surface modifications were designed for implantation in the CNS. The electrode surfaces were modified with nano-scale structures that could greatly increase the active surface area in order to enhance the electrochemical current outputs while maintaining micro-scale dimensions of the electrodes and probes. The electrodes were made of gold or platinum, and designed with different sizes. The silicon probes were modified by silicon nanowires fabricated with the vapor-liquid-solid mechanism at high temperatures. With polyimide substrates, the nanostructure modification was carried out by applying concentrated gold or silver colloid solutions onto the micro-electrodes at room temperature. The surfaces of electrodes before and after modification were observed by scanning electron microscopy. The silicon nanowire-modified surface was characterized by cyclic voltammetry. Experiments were carried out to investigate the improvement in sensing performance. The modified electrodes were tested with H2O2, electrochemical L-glutamate and dopamine. Comparisons between electrodes with and without nanostructure modification were conducted showing that the modifications have enhanced the signal outputs of the electrochemical neurotransmitter sensors.

When gene medication is also genetic modification--regulating DNA treatment.

Science.gov (United States)

Foss, Grethe S; Rogne, Sissel

2007-07-26

The molecular methods used in DNA vaccination and gene therapy resemble in many ways the methods applied in genetic modification of organisms. In some regulatory regimes, this creates an overlap between 'gene medication' and genetic modification. In Norway, an animal injected with plasmid DNA, in the form of DNA vaccine or gene therapy, currently is viewed as being genetically modified for as long as the added DNA is present in the animal. However, regulating a DNA-vaccinated animal as genetically modified creates both regulatory and practical challenges. It is also counter-intuitive to many biologists. Since immune responses can be elicited also to alter traits, the borderline between vaccination and the modification of properties is no longer distinct. In this paper, we discuss the background for the Norwegian interpretation and ways in which the regulatory challenge can be handled.

Attention bias modification for anxiety and phobias: current status and future directions.

Science.gov (United States)

Kuckertz, Jennie M; Amir, Nader

2015-02-01

Attention bias modification (ABM) was introduced over a decade ago as a computerized method of manipulating attentional bias and has been followed by intense interest in applying ABM for clinical purposes. While meta-analyses support ABM as a method of modifying attentional biases and reducing anxiety symptoms, there have been notable discrepancies in findings published within the last several years. In this review, we comment on recent research that may help explain some of the inconsistencies across ABM studies. More relevant to the future of ABM research, we highlight areas in which continuing research is needed. We suggest that ABM appears to be a promising treatment for anxiety disorders, but relative to other interventions, ABM is in its infancy. Thus, research is needed in order to improve ABM as a clinical treatment and advance the psychological science of ABM.

A simultaneous description of fast wave e-TTMP and ion current drive effects on shear in a tokamak: theory and experiments in JET

International Nuclear Information System (INIS)

Bhatnagar, V.P.; Bosia, G.; Jacquinot, J.; Porcelli, F.

1993-01-01

A controlled local modification of the plasma-current profile, the safety factor q or shear (dq/dr) in a tokamak can lead to an improvement in its performance. For example, enhanced confinement in JET discharges with deep pellet injection is found to be associated with a reversal of the shear. Also, a significant control over the sawteeth behaviour in the JET tokamak has been found to occur when the shear at the q = 1 surface is modified by a dipolar-current driven by ICRF in the minority-ion heating regime. This could give a handle on the ejection of fast particles and hence on burn control in a reactor. The above sawtooth control may also be used to ease the ash removal in a reactor. When an ICRH antenna array is phased (Δφ ≠ 0 or π), the excited asymmetric k // -spectrum can drive non inductive currents by interaction of waves both with electrons (TTMP and e-Landau damping) and ions at minority (fundamental) or harmonic cyclotron resonances depending upon the scenario. Therefore, in any modeling of ICRF current drive, both (electron and ion) current drive mechanisms must be included simultaneously to correctly represent the non inductive current drive profile. To devise scenarios of shear control by minority current drive, that take advantage of the inherent electron current drive as well, we have developed a model based on earlier theories to calculate, for the first time, the two effects simultaneously. (author) 11 refs., 5 figs

An integrative analysis of post-translational histone modifications in the marine diatom Phaeodactylum tricornutum

KAUST Repository

Veluchamy, Alaguraj

2015-05-20

Background: Nucleosomes are the building blocks of chromatin where gene regulation takes place. Chromatin landscapes have been profiled for several species, providing insights into the fundamental mechanisms of chromatin-mediated transcriptional regulation of gene expression. However, knowledge is missing for several major and deep-branching eukaryotic groups, such as the Stramenopiles, which include the diatoms. Diatoms are highly diverse and ubiquitous species of phytoplankton that play a key role in global biogeochemical cycles. Dissecting chromatin-mediated regulation of genes in diatoms will help understand the ecological success of these organisms in contemporary oceans. Results: Here, we use high resolution mass spectrometry to identify a full repertoire of post-translational modifications on histones of the marine diatom Phaeodactylum tricornutum, including eight novel modifications. We map five histone marks coupled with expression data and show that P. tricornutum displays both unique and broadly conserved chromatin features, reflecting the chimeric nature of its genome. Combinatorial analysis of histone marks and DNA methylation demonstrates the presence of an epigenetic code defining activating or repressive chromatin states. We further profile three specific histone marks under conditions of nitrate depletion and show that the histone code is dynamic and targets specific sets of genes. Conclusions: This study is the first genome-wide characterization of the histone code from a stramenopile and a marine phytoplankton. The work represents an important initial step for understanding the evolutionary history of chromatin and how epigenetic modifications affect gene expression in response to environmental cues in marine environments. © 2015 Veluchamy et al.

Eddy current spectroscopy for near-surface residual stress profiling in surface treated nonmagnetic engine alloys

Science.gov (United States)

Abu-Nabah, Bassam A.

Recent research results indicated that eddy current conductivity measurements can be exploited for nondestructive evaluation of near-surface residual stresses in surface-treated nickel-base superalloy components. Most of the previous experimental studies were conducted on highly peened (Almen 10-16A) specimens that exhibit harmful cold work in excess of 30% plastic strain. Such high level of cold work causes thermo-mechanical relaxation at relatively modest operational temperatures; therefore the obtained results were not directly relevant to engine manufacturers and end users. The main reason for choosing peening intensities in excess of recommended normal levels was that in low-conductivity engine alloys the eddy current penetration depth could not be forced below 0.2 mm without expanding the measurements above 10 MHz which is beyond the operational range of most commercial eddy current instruments. As for shot-peened components, it was initially felt that the residual stress effect was more difficult to separate from cold work, texture, and inhomogeneity effects in titanium alloys than in nickel-base superalloys. In addition, titanium alloys have almost 50% lower electric conductivity than nickel-base superalloys; therefore require proportionally higher inspection frequencies, which was not feasible until our recent breakthrough in instrument development. Our work has been focused on six main aspects of this continuing research, namely, (i) the development of an iterative inversion technique to better retrieve the depth-dependent conductivity profile from the measured frequency-dependent apparent eddy current conductivity (AECC), (ii) the extension of the frequency range up to 80 MHz to better capture the peak compressive residual stress in nickel-base superalloys using a new eddy current conductivity measuring system, which offers better reproducibility, accuracy and measurement speed than the previously used conventional systems, (iii) the lift-off effect on

Surface modification of titanium and titanium alloys by ion implantation.

Science.gov (United States)

Rautray, Tapash R; Narayanan, R; Kwon, Tae-Yub; Kim, Kyo-Han

2010-05-01

Titanium and titanium alloys are widely used in biomedical devices and components, especially as hard tissue replacements as well as in cardiac and cardiovascular applications, because of their desirable properties, such as relatively low modulus, good fatigue strength, formability, machinability, corrosion resistance, and biocompatibility. However, titanium and its alloys cannot meet all of the clinical requirements. Therefore, to improve the biological, chemical, and mechanical properties, surface modification is often performed. In view of this, the current review casts new light on surface modification of titanium and titanium alloys by ion beam implantation. (c) 2010 Wiley Periodicals, Inc.

Applications of high power microwaves to atmospheric modification and measurement

International Nuclear Information System (INIS)

Benford, J.

1993-01-01

The current state of proposals to use high power microwaves in the atmosphere is reviewed. HPM has been proposed to aid in the conservation of stratospheric ozone by partial breakdown, facilitating chemistry to eliminate chlorine. Another proposal is over-the-horizon radar using a partial breakdown area in the ionosphere. A key to any such effort is rapid diagnosis of the state of the atmosphere before, during and after intervention. Technology requirements of these modification and measurement proposals are reviewed. The elements of an atmospheric modification program are identified and political, economic and ideological factors are discussed

Improvement of Carbon Dioxide Sweep Efficiency by Utilization of Microbial Permeability Profile Modification to Reduce the Amount of Oil Bypassed During Carbon Dioxide Flood

Energy Technology Data Exchange (ETDEWEB)

Schmitz, Darrel [Mississippi State Univ., Mississippi State, MS (United States); Brown, Lewis [Mississippi State Univ., Mississippi State, MS (United States); Lynch, F. Leo [Mississippi State Univ., Mississippi State, MS (United States); Kirkland, Brenda L. [Mississippi State Univ., Mississippi State, MS (United States); Collins, Krystal M. [Mississippi State Univ., Mississippi State, MS (United States); Funderburk, William K. [Mississippi State Univ., Mississippi State, MS (United States)

2010-12-31

The objective of this project was to couple microbial permeability profile modification (MPPM), with carbon dioxide flooding to improve oil recovery from the Upper Cretaceous Little Creek Oil Field situated in Lincoln and Pike counties, MS. This study determined that MPPM technology, which improves production by utilizing environmentally friendly nutrient solutions to simulate the growth of the indigenous microflora in the most permeable zones of the reservoir thus diverting production to less permeable, previously unswept zones, increased oil production without interfering with the carbon dioxide flooding operation. Laboratory tests determined that no microorganisms were produced in formation waters, but were present in cores. Perhaps the single most significant contribution of this study is the demonstration that microorganisms are active at a formation temperature of 115°C (239°F) by using a specially designed culturing device. Laboratory tests were employed to simulate the MPPM process by demonstrating that microorganisms could be activated with the resulting production of oil in coreflood tests performed in the presence of carbon dioxide at 66°C (the highest temperature that could be employed in the coreflood facility). Geological assessment determined significant heterogeneity in the Eutaw Formation, and documented relatively thin, variably-lithified, well-laminated sandstone interbedded with heavily-bioturbated, clay-rich sandstone and shale. Live core samples of the Upper Cretaceous Eutaw Formation from the Heidelberg Field, MS were quantitatively assessed using SEM, and showed that during MPPM permeability modification occurs ubiquitously within pore and throat spaces of 10-20 μm diameter. Testing of the MPPM procedure in the Little Creek Field showed a significant increase in production occurred in two of the five production test wells; furthermore, the decline curve in each of the production wells became noticeably less steep. This project greatly

Physics issues of high bootstrap current tokamaks

International Nuclear Information System (INIS)

Ozeki, T.; Azumi, M.; Ishii, Y.

1997-01-01

Physics issues of a tokamak plasma with a hollow current profile produced by a large bootstrap current are discussed based on experiments in JT-60U. An internal transport barrier for both ions and electrons was obtained just inside the radius of zero magnetic shear in JT-60U. Analysis of the toroidal ITG microinstability by toroidal particle simulation shows that weak and negative shear reduces the toroidal coupling and suppresses the ITG mode. A hard beta limit was observed in JT-60U negative shear experiments. Ideal MHD mode analysis shows that the n = 1 pressure-driven kink mode is a plausible candidate. One of the methods to improve the beta limit against the kink mode is to widen the negative shear region, which can induce a broader pressure profile resulting in a higher beta limit. The TAE mode for the hollow current profile is less unstable than that for the monotonic current profile. The reason is that the continuum gaps near the zero shear region are not aligned when the radius of q min is close to the region of high ∇n e . Finally, a method for stable start-up for a plasma with a hollow current profile is describe, and stable sustainment of a steady-state plasma with high bootstrap current is discussed. (Author)

Effects of Cognitive Bias Modification Training via Smartphones

Directory of Open Access Journals (Sweden)

Ranming Yang

2017-08-01

Full Text Available Background and Objectives: Negative cognitive biases have been linked to anxiety and mood problems. Accumulated data from laboratory studies show that positive and negative interpretation styles with accompanying changes in mood can be induced through cognitive bias modification (CBM paradigms. Despite the therapeutic potential of positive training effects, few studies have explored training paradigms administered via smartphones. The current study aimed to compare the effectiveness of three different types of training programmes (cognitive bias modification-attention, CBM-A; cognitive bias modification-interpretation, CBM-I; attention and interpretation modification, AIM administered via smart-phones by using a control condition (CC.Methods:Seventy-six undergraduate participants with high social anxiety (Liebowitz Social Anxiety Scale, LSAS ≥ 30 were randomly assigned to four groups: CBM-A (n = 20, CBM-I (n = 20, AIM (n = 16, and CC (n = 20.Results: The results showed that the effects of CBM training, CBM-I training, or AIM training vs. CC for attention yielded no significant differences in dot-probe attention bias scores. The CBM-I group showed significantly less threat interpretation and more benign interpretation than the CC group on interpretation bias scores.Conclusions: The present results supported the feasibility of delivering CBM-I via smartphones, but the effectiveness of CBM-A and AIM training via smartphones was limited.

A GIS-based Computational Tool for Multidimensional Flow Velocity by Acoustic Doppler Current Profilers

International Nuclear Information System (INIS)

Kim, D; Winkler, M; Muste, M

2015-01-01

Acoustic Doppler Current Profilers (ADCPs) provide efficient and reliable flow measurements compared to other tools for characteristics of the riverine environments. In addition to originally targeted discharge measurements, ADCPs are increasingly utilized to assess river flow characteristics. The newly developed VMS (Velocity Mapping Software) aims at providing an efficient process for quality assurance, mapping velocity vectors for visualization and facilitating comparison with physical and numerical model results. VMS was designed to provide efficient and smooth work flows for processing groups of transects. The software allows the user to select group of files and subsequently to conduct statistical and graphical quality assurance on the files as a group or individually as appropriate. VMS also enables spatial averaging in horizontal and vertical plane for ADCP data in a single or multiple transects over the same or consecutive cross sections. The analysis results are displayed in numerical and graphical formats. (paper)

Reduction of structural inhomogeneity of 35GL alloys through modification by means of electric emission current in the process of crystallization

Directory of Open Access Journals (Sweden)

Олена Миколаївна Жбанова

2017-07-01

Full Text Available The method of a crystallizing alloy processing which makes it possible to obtain high-quality castings from 35GL steel has been considered. It has been shown that the electro impulse treatment of the melt improves the structure and reduces the physical heterogeneity of the castings. Processing of the melt with a current substantially increases the dissolution rate of metallic impurities and other components in the melt, provides a fine-grained structure, increases the homogeneity of the cast metal as well. The structural heterogeneity decreases as a result of the change in morphology and disorientation and as a result of manganese carbides grinding the size and quantity of the grain ball decrease from 7 to 8. Physical heterogeneity reduces due to the changes in the location and size of pores and nonmetallic inclusions; the content of gases and non-metallic inclusions reduces as well. In this article, studies of the modification of certain parameters by the electric impulse current, have been made. It results in a significant increase in the basic mechanical properties of the 35GL cast structural steel: the tensile strength increases by 9%, the toughness increases by 21%, and the hardness by 6% without changing the chemical composition of the steel, due to the fine grain structure

Ohmic ion temperature and thermal diffusivity profiles from the JET neutron emission profile monitor

Energy Technology Data Exchange (ETDEWEB)

Esposito, B. (ENEA, Frascati (Italy). Centro Ricerche Energia); Marcus, F.B.; Conroy, S.; Jarvis, O.N.; Loughlin, M.J.; Sadler, G.; Belle, P. van (Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking); Adams, J.M.; Watkins, N. (AEA Industrial Technology, Harwell (United Kingdom))

1993-10-01

The JET neutron emission profile monitor was used to study ohmically heated deuterium discharges. The radial profile of the neutron emissivity is deduced from the line-integral data. The profiles of ion temperature, T[sub i], and ion thermal diffusivity, [chi][sub i], are derived under steady-state conditions. The ion thermal diffusivity is higher than, and its scaling with plasma current opposite to, that predicted by neoclassical theory. (author).

Ohmic ion temperature and thermal diffusivity profiles from the JET neutron emission profile monitor

International Nuclear Information System (INIS)

Esposito, B.

1993-01-01

The JET neutron emission profile monitor was used to study ohmically heated deuterium discharges. The radial profile of the neutron emissivity is deduced from the line-integral data. The profiles of ion temperature, T i , and ion thermal diffusivity, χ i , are derived under steady-state conditions. The ion thermal diffusivity is higher than, and its scaling with plasma current opposite to, that predicted by neoclassical theory. (author)

Modification of Turbulent Pipe Flow Equations to Estimate the Vertical Velocity Profiles Under Woody Debris Jams

Science.gov (United States)

Cervania, A.; Knack, I. M. W.

2017-12-01

The presence of woody debris (WD) jams in rivers and streams increases the risk of backwater flooding and reduces the navigability of a channel, but adds fish and macroinvertebrate habitat to the stream. When designing river engineering projects engineers use hydraulic models to predict flow behavior around these obstructions. However, the complexities of flow through and beneath WD jams are still poorly understood. By increasing the ability to predict flow behavior around WD jams, landowners and engineers are empowered to develop sustainable practices regarding the removal or placement of WD in rivers and flood plains to balance the desirable and undesirable effects to society and the environment. The objective of this study is to address some of this knowledge gap by developing a method to estimate the vertical velocity profile of flow under WD jams. When flow passes under WD jams, it becomes affected by roughness elements on all sides, similar to turbulent flows in pipe systems. Therefore, the method was developed using equations that define the velocity profiles of turbulent pipe flows: the law of the wall, the logarithmic law, and the velocity defect law. Flume simulations of WD jams were conducted and the vertical velocity profiles were measured along the centerline. A calculated velocity profile was fit to the measured profile through the calibration of eight parameters. An optimal value or range of values have been determined for several of these parameters using cross-validation techniques. The results indicate there may be some promise to using this method in hydraulic models.

Pulsed electric field-assisted modification of pectin from sugar beet pulp.

Science.gov (United States)

Ma, Sen; Wang, Zhong-he

2013-02-15

This current work is concerned with the modification of sugar beet pulp (SBP) pectin assisted by pulsed electric filed (PEF) without solvent. Pectin-arachates with degree of esterification (DE) ranging from 49 to 84 were prepared in one-step modification. The results showed that the DE of pectin derivatives increased significantly with the PEF intensity from 18 to 30 kV cm((1) and total specific energy input from 124 to 345 J mL((1). Evidence of modification of pectin was provided by FT-IR, X-ray diffraction patterns and NMR spectra. Thermogravimetric investigation of modified pectin indicated a higher thermal stability than the untreated one. Results revealed that PEF technology is a promising method for industrial manufacture of pectin derivatives. Copyright © 2012 Elsevier Ltd. All rights reserved.

Mapping of Complete Set of Ribose and Base Modifications of Yeast rRNA by RP-HPLC and Mung Bean Nuclease Assay.

Directory of Open Access Journals (Sweden)

Jun Yang

Full Text Available Ribosomes are large ribonucleoprotein complexes that are fundamental for protein synthesis. Ribosomes are ribozymes because their catalytic functions such as peptidyl transferase and peptidyl-tRNA hydrolysis depend on the rRNA. rRNA is a heterogeneous biopolymer comprising of at least 112 chemically modified residues that are believed to expand its topological potential. In the present study, we established a comprehensive modification profile of Saccharomyces cerevisiae's 18S and 25S rRNA using a high resolution Reversed-Phase High Performance Liquid Chromatography (RP-HPLC. A combination of mung bean nuclease assay, rDNA point mutants and snoRNA deletions allowed us to systematically map all ribose and base modifications on both rRNAs to a single nucleotide resolution. We also calculated approximate molar levels for each modification using their UV (254nm molar response factors, showing sub-stoichiometric amount of modifications at certain residues. The chemical nature, their precise location and identification of partial modification will facilitate understanding the precise role of these chemical modifications, and provide further evidence for ribosome heterogeneity in eukaryotes.

Profiling the Mobile Customer

DEFF Research Database (Denmark)

Jessen, Pernille Wegener; King, Nancy J.

2010-01-01

of significant concerns about privacy and data protection. This second article in a two part series on "Profiling the Mobile Customer" explores how to best protect consumers' privacy and personal data through available mechanisms that include industry self-regulation, privacy-enhancing technologies...... discusses the current limitations of using technology to protect consumers from privacy abuses related to profiling. Concluding that industry self-regulation and available privacy-enhancing technologies will not be adequate to close important privacy gaps related to consumer profiling without legislative...

Polysaccharides from Traditional Chinese Medicines: Extraction, Purification, Modification, and Biological Activity.

Science.gov (United States)

Chen, Yun; Yao, Fangke; Ming, Ke; Wang, Deyun; Hu, Yuanliang; Liu, Jiaguo

2016-12-13

Traditional Chinese Medicine (TCM) has been used to treat diseases in China for thousands of years. TCM compositions are complex, using as their various sources plants, animals, fungi, and minerals. Polysaccharides are one of the active and important ingredients of TCMs. Polysaccharides from TCMs exhibit a wide range of biological activities in terms of immunity- modifying, antiviral, anti-inflammatory, anti-oxidative, and anti-tumor properties. With their widespread biological activities, polysaccharides consistently attract scientist's interests, and the studies often concentrate on the extraction, purification, and biological activity of TCM polysaccharides. Currently, numerous studies have shown that the modification of polysaccharides can heighten or change the biological activities, which is a new angle of polysaccharide research. This review highlights the current knowledge of TCM polysaccharides, including their extraction, purification, modification, and biological activity, which will hopefully provide profound insights facilitating further research and development.

Stability of a plasma filament with a skinned current

International Nuclear Information System (INIS)

Blekher, P.M.

1984-01-01

An effective sufficient condition of existence of ideal helical plasma filament instability in a strong longitUdinal magnetic field for skinned current profiles is deduced in the paper. The results of numerical calculations of current skinned profiles of instability diagrams are presented and these results are compared with the obtained sufficient condition. An analytical solution for one model current profile skinning and this solution also is compared with the sufficient condition of instability

Modal Profiles for the WISC-III.

Science.gov (United States)

Pritchard, David A.; Livingston, Ronald B.; Reynolds, Cecil R.; Moses, James A., Jr.

2000-01-01

Presents a normative typology for classifying the Wechsler Intelligence Scale for Children-Third Edition (WISC-III) factor index profiles according to profile shape. Current analyses indicate that overall profile level accounted for a majority of the variance in WISC-III index scores, but a considerable proportion of the variance was because of…

Modification of critical current in HTSC tape conductors by a ferromagnetic layer

International Nuclear Information System (INIS)

Goemoery, F; Souc, J; Seiler, E; Vojenciak, M; Granados, X

2008-01-01

In some applications of tape conductors from high temperature superconductors (HTSC) the magnetic field is created by the transported current itself. This is e.g. the case of power transmission cables or current leads. Quite complex distribution of local magnetic field determines then the ability of the superconducting element to carry electrical current. We have investigated how much the critical current of a tape conductor can be changed by putting a ferromagnetic layer in the vicinity of the HTSC material. Numerical procedure has been developed to resolve the current and field distribution in such superconductor-ferromagnet composite tape. Theoretical predictions have been confirmed by experiments on sample made from Bi-2223/Ag composite tape. The critical current of such tape can be improved by placing a soft ferromagnetic material at the tape's edges. On the other hand, the calculations show that the ferromagnetic substrate of YBCO coated tape reduces its self-field critical current

Epigenetic modifications: An important mechanism in diabetic disturbances.

Science.gov (United States)

Rorbach-Dolata, Anna; Kubis, Adriana; Piwowar, Agnieszka

2017-11-29

In the search for explanations of diabetes pathomechanisms, especially the development of its vascular complications (micro- and macrovascular ), although current, good metabolic control of diabetes, attention was drawn to the role of epigenetic inheritance associated with epigenetic modifications of histone proteins and DNA in hyperglycemia conditions. This study showed the significant role of DNA methylation and histone epigenetic modifications (a different nature and a different degree) in the transmission of information that is not connected with gene inheritance but concerns the persistent changes induced by hyperglycemia..Attention was paid to the role of DNA methylation of pancreatic cells in the pathogenesis of type 1 diabetes, but also type 2. The important role of DNA methylation changes in a so-called intrauterine growth restriction (IUGR) as reason of subsequent development of diabetes was particularly emphasized. In the pathogenesis of type 2 diabetes and its complications, especially microvascular complications, the greatest share and importance of epigenetic modifications on mitochondrial DNA metylation are the most important. The multidirectionality Complicaand complexity of epigenetic modifications of histone proteins indicate their importance in the development of diabetic disturbances. An especially important role is attributed to methylation and acetylation of histone proteins, in particular on arginine and lysine, whose changes occur most frequently. Moreover, epigenetic modifications of the enzymes, especially methylases, responsible for these processes are the underlying. It has been indicated that the identification of epigenetic differences within the DNA or histone proteins may be a useful prognostic biomarker of susceptibility to the disease development in the future. Moreover, they may become a potential target for future therapeutic interventions for clinical disorders in diabetes.

Ti(r) profiles from the JET neutron profile monitor for ohmic discharges

Energy Technology Data Exchange (ETDEWEB)

Esposito, B. (ENEA, Frascati (Italy). Centro Ricerche Energia); Marcus, F.B.; Conroy, S.; Jarvis, O.N.; Loughlin, M.J.; Sadler, G.; Belle, P. van (Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking); Adams, J.M.; Watkins, N. (AEA Industrial Technology, Harwell (United Kingdom))

1991-01-01

A study has been made of the neutron emissivity, using the JET neutron profile monitor, obtained for ohmically heated deuterium discharges. Both one-dimensional (1-D) best-fit inversion procedures and 2-D tomography have been used to deduce the radial profile of the neutron emission from the line-integral data. The profiles of ion temperature and ion thermal conductivity are then derived. The scaling of the ion thermal conductivity with plasma current is found to be opposite to that of neoclassical theory. (author) 4 refs., 5 figs.

Development of a high current 60 keV neutral lithium beam injector for beam emission spectroscopy measurements on fusion experiments

Science.gov (United States)

Anda, G.; Dunai, D.; Lampert, M.; Krizsanóczi, T.; Németh, J.; Bató, S.; Nam, Y. U.; Hu, G. H.; Zoletnik, S.

2018-01-01

A 60 keV neutral lithium beam system was designed and built up for beam emission spectroscopy measurement of edge plasma on the KSTAR and EAST tokamaks. The electron density profile and its fluctuation can be measured using the accelerated lithium beam-based emission spectroscopy system. A thermionic ion source was developed with a SiC heater to emit around 4-5 mA ion current from a 14 mm diameter surface. The ion optic is following the 2 step design used on other devices with small modifications to reach about 2-3 cm beam diameter in the plasma at about 4 m from the ion source. A newly developed recirculating sodium vapour neutralizer neutralizes the accelerated ion beam at around 260-280 °C even during long (manipulation techniques are applied to allow optimization, aiming, cleaning, and beam modulation. The maximum 60 keV beam energy with 4 mA ion current was successfully reached at KSTAR and at EAST. Combined with an efficient observation system, the Li-beam diagnostic enables the measurement of the density profile and fluctuations on the plasma turbulence time scale.

Proceedings of the international symposium on research reactor safety operations and modifications

International Nuclear Information System (INIS)

1990-03-01

The International Symposium on Research Reactor Safety, Operations and Modifications was organized by the International Atomic Energy Agency in cooperation with Atomic Energy of Canada Limited-Research Company. The main objectives of this Symposium were: (1) to exchange information and to discuss current perspectives and concerns relating to all aspects to research reactor safety, operations, and modifications; and, (2) to present views and to discuss future initiatives and directions for research reactor design, operations, utilization, and safety. The symposium topics included: research reactor programmes and experience; research reactor design safety and analysis; research reactor modifications and decommissioning; research reactor licensing; and new research reactors. These topics were covered during eight oral sessions and three poster sessions. These Proceedings include the full text of the 93 papers presented. The subject of Symposium was quite wide-ranging in that it covered essentially all aspects of research reactor safety, operations, and modifications. This was considered to be appropriate and timely given the 326 research reactors currently in operation in some 56 countries; given the degree of their utilization which ranges from pure and applied research to radioisotopes production to basic training and manpower development; and given that many of these reactors are undergoing extensive modifications, core conversions, power upratings, and are becoming the subject of safety reassessment and regulatory reviews. Although the Symposium covered many topics, the majority of papers and discussions tended to focus mainly on research reactor safety. This was seen as a clear sign of the continuing recognition of the fundamental importance of identifying and addressing, particularly through international cooperation, issues and concerns associated with research reactor safety

NF-Y dependent epigenetic modifications discriminate between proliferating and postmitotic tissue

DEFF Research Database (Denmark)

Gurtner, Aymone; Fuschi, Paola; Magi, Fiorenza

2008-01-01

The regulation of gene transcription requires posttranslational modifications of histones that, in concert with chromatin remodeling factors, shape the structure of chromatin. It is currently under intense investigation how this structure is modulated, in particular in the context of proliferatio...

Variations of current profiles in tokamaks. Formation mechanism and confinement property of current-hole configuration

International Nuclear Information System (INIS)

Takizuka, Tomonori

2003-01-01

The formation mechanism of the current hole in tokamak plasmas is reviewed. Experimental results of JT-60U are shown. Increase of the off-central noninductive current is a key factor for the current-hole formation. The internal Transport Barrier (ITB), which generates large bootstrap current, plays an important role. The central current density in the hole stays nearly 0. The idea of a new equilibrium for a tokamak plasma with a current hole is introduced. This equilibrium configuration called Axisymmetric Tri-Magnetic-Islands (ATMI) equilibrium', has three islands along the R direction (a central-negative-current island and side-positive-current islands). The equilibrium is stable with the elongation coils when the current in the ATMI region is limited to a small amount. The confinement properties of a current-hole configuration with box-type ITB is described. A scaling of the core poloidal beta inside the ITB, β p,core , is given as ε f β p,core approx. = 1, which suggests the equilibrium limit (ε f : inverse aspect ratio at the ITB foot). Though the core stored energy is little dependent on the heating power, the estimated heat diffusivity in the ITB region moderately correlates with a neoclassical diffusivity. (author)

Surface waves on currents with arbitrary vertical shear

Science.gov (United States)

Smeltzer, Benjamin K.; Ellingsen, Simen Å.

2017-04-01

We study dispersion properties of linear surface gravity waves propagating in an arbitrary direction atop a current profile of depth-varying magnitude using a piecewise linear approximation and develop a robust numerical framework for practical calculation. The method has been much used in the past for the case of waves propagating along the same axis as the background current, and we herein extend and apply it to problems with an arbitrary angle between the wave propagation and current directions. Being valid for all wavelengths without loss of accuracy, the scheme is particularly well suited to solve problems involving a broad range of wave vectors, such as ship waves and Cauchy-Poisson initial value problems. We examine the group and phase velocities over different wavelength regimes and current profiles, highlighting characteristics due to the depth-variable vorticity. We show an example application to ship waves on an arbitrary current profile and demonstrate qualitative differences in the wake patterns between concave down and concave up profiles when compared to a constant shear profile with equal depth-averaged vorticity. We also discuss the nature of additional solutions to the dispersion relation when using the piecewise-linear model. These are vorticity waves, drifting vortical structures which are artifacts of the piecewise model. They are absent for a smooth profile and are spurious in the present context.

Susceptibility profiles of Nocardia isolates based on current taxonomy.

Science.gov (United States)

Schlaberg, Robert; Fisher, Mark A; Hanson, Kimberley E

2014-01-01

The genus Nocardia has undergone rapid taxonomic expansion in recent years, and an increasing number of species are recognized as human pathogens. Many established species have predictable antimicrobial susceptibility profiles, but sufficient information is often not available for recently described organisms. Additionally, the effectiveness of sulfonamides as first-line drugs for Nocardia has recently been questioned. This led us to review antimicrobial susceptibility patterns for a large number of molecularly identified clinical isolates. Susceptibility results were available for 1,299 isolates representing 39 different species or complexes, including 11 that were newly described, during a 6-year study period. All tested isolates were susceptible to linezolid. Resistance to trimethoprim-sulfamethoxazole (TMP-SMX) was rare (2%) except among Nocardia pseudobrasiliensis (31%) strains and strains of the N. transvalensis complex (19%). Imipenem susceptibility varied for N. cyriacigeorgica and N. farcinica, as did ceftriaxone susceptibility of the N. nova complex. Resistance to more than one of the most commonly used drugs (amikacin, ceftriaxone, TMP-SMX, and imipenem) was highest for N. pseudobrasiliensis (100%), N. transvalensis complex (83%), N. farcinica (68%), N. puris (57%), N. brasiliensis (51%), N. aobensis (50%), and N. amikacinitolerans (43%). Thus, while antimicrobial resistance can often be predicted, susceptibility testing should still be considered when combination therapy is warranted, for less well characterized species or those with variable susceptibility profiles, and for patients with TMP-SMX intolerance.

PEEK with Reinforced Materials and Modifications for Dental Implant Applications

Directory of Open Access Journals (Sweden)

Fitria Rahmitasari

2017-12-01

Full Text Available Polyetheretherketone (PEEK is a semi-crystalline linear polycyclic thermoplastic that has been proposed as a substitute for metals in biomaterials. PEEK can also be applied to dental implant materials as a superstructure, implant abutment, or implant body. This article summarizes the current research on PEEK applications in dental implants, especially for the improvement of PEEK surface and body modifications. Although various benchmark reports on the reinforcement and surface modifications of PEEK are available, few clinical trials using PEEK for dental implant bodies have been published. Controlled clinical trials, especially for the use of PEEK in implant abutment and implant bodies, are necessary.

Profiles of current speed, direction and other data from ADCP casts from MULTIPLE SHIPS from 01 January 1996 to 25 May 1999 (NODC Accession 9900096)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Profiles of current speed , direction and other data from ADCP casts from MULTIPLE SHIPS. Data were collected by the University of Hawaii at Manoa (UHM) from 01...

Modifications to POISSON

International Nuclear Information System (INIS)

Harwood, L.H.

1981-01-01

At MSU we have used the POISSON family of programs extensively for magnetic field calculations. In the presently super-saturated computer situation, reducing the run time for the program is imperative. Thus, a series of modifications have been made to POISSON to speed up convergence. Two of the modifications aim at having the first guess solution as close as possible to the final solution. The other two aim at increasing the convergence rate. In this discussion, a working knowledge of POISSON is assumed. The amount of new code and expected time saving for each modification is discussed

DNA modification by sulfur mustards and nitrosoureas and repair of these lesions

International Nuclear Information System (INIS)

Ludlum, D.B.; Papirmeister, B.; Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD)

1986-01-01

The nature and significance of DNA modifications caused by chloroethyl ethyl sulfide (CEES) is compared with those produced by chloroethyl cyclohexyl nitrosourea (CCNU). This comparison illustrates the differences in the kind of biological response which can arise from DNA modification by different agents and the role of DNA repair in determining this response. In particular, the ability of tumor cells to become resistant to therapeutic agents has some important implications for the ability of cells in general to tolerate environmental mutagens. DNA modification by CEES and CCNU can be viewed in the context of DNA modification caused by compounds which naturally react with DNA. For example, cycasin and S-adenosylmethionine both methylate DNA. Not surprisingly, a variety of repair mechanisms has evolved which serve to maintain the integrity of DNA in the presence of such naturally-occurring DNA modifiers. The ability of these enzymes to repair other DNA lesions is currently under active investigation as described here. 19 refs., 4 figs., 3 tabs

Modeling and control of the current density profile in Tokamaks and its relation to electron transport

International Nuclear Information System (INIS)

Zucca, C.

2009-04-01

current drive schemes employed. The increase of confinement with the negative magnetic shear was observed to be gradual, but constant, and did not depend on specific values of the safety factor. Therefore, the transition from standard to improved confinement appeared to be smooth, although it can be very fast. The flexible EC system in TCV allowed us to attain strong global confinement improvement to produce eITB regimes. It also permitted us to perform transport studies on plasmas characterized by low confinement, in which we modified the magnetic shear profile, locally, around the deposition location. For instance, alternate and periodic injection of co- and counter-ECCD within the same plasma discharge has been realized on TCV, while maintaining the same amount of total input EC power. Such a heating scheme has been the basis of Swing ECCD experiments, which were initially carried out using nearly off-axis EC deposition locations in the plasma, in order to maximize the EC power absorption, and therefore the magnetic shear variation. ASTRA, interfaced with the experimental data and the CQL3D code for the computation of the EC heating and current drive sources, has again been used as a reliable tool for transport analysis and planning of new experiments. The simulations have pointed out the effects of Swing ECCD on the magnetic shear and on the electron temperature profile around the radius at which the EC waves are absorbed. Both profiles turned out to be modulated at the same frequency as the frequency of the Swing ECCD. Moreover, the maximum magnetic shear variation has been observed to be independent of the transport models used for the simulations, therefore underlying the robustness of the modeling. Additionally, the numerical results have motivated further experiments with more off-axis EC deposition, which were found roughly in agreement with recent gyrokinetic predictions, according to which, at higher positive values of the magnetic shear, an inversion of the

Effects of Cognitive Bias Modification Training via Smartphones

OpenAIRE

Ranming Yang; Ranming Yang; Lixia Cui; Feng Li; Jing Xiao; Qin Zhang; Tian P. S. Oei; Tian P. S. Oei

2017-01-01

Background and Objectives: Negative cognitive biases have been linked to anxiety and mood problems. Accumulated data from laboratory studies show that positive and negative interpretation styles with accompanying changes in mood can be induced through cognitive bias modification (CBM) paradigms. Despite the therapeutic potential of positive training effects, few studies have explored training paradigms administered via smartphones. The current study aimed to compare the effectiveness of three...

Fault-current limiter using a superconducting coil

International Nuclear Information System (INIS)

Boenig, H.J.; Paice, D.A.

1982-01-01

A novel circuit, consisting of solid-state diodes and a biased superconducting coil, for limiting the fault currents in three-phase ac systems is presented. A modification of the basic circuit results in a solid-state ac breaker with current-limiting features. The operating characteristics of the fault-current limiter and the ac breaker are analyzed. An optimization procedure for sizing the superconducting coil is derived

Genetic variability in MCF-7 sublines: evidence of rapid genomic and RNA expression profile modifications

International Nuclear Information System (INIS)

Nugoli, Mélanie; Theillet, Charles; Chuchana, Paul; Vendrell, Julie; Orsetti, Béatrice; Ursule, Lisa; Nguyen, Catherine; Birnbaum, Daniel; Douzery, Emmanuel JP; Cohen, Pascale

2003-01-01

Both phenotypic and cytogenetic variability have been reported for clones of breast carcinoma cell lines but have not been comprehensively studied. Despite this, cell lines such as MCF-7 cells are extensively used as model systems. In this work we documented, using CGH and RNA expression profiles, the genetic variability at the genomic and RNA expression levels of MCF-7 cells of different origins. Eight MCF-7 sublines collected from different sources were studied as well as 3 subclones isolated from one of the sublines by limit dilution. MCF-7 sublines showed important differences in copy number alteration (CNA) profiles. Overall numbers of events ranged from 28 to 41. Involved chromosomal regions varied greatly from a subline to another. A total of 62 chromosomal regions were affected by either gains or losses in the 11 sublines studied. We performed a phylogenetic analysis of CGH profiles using maximum parsimony in order to reconstruct the putative filiation of the 11 MCF-7 sublines. The phylogenetic tree obtained showed that the MCF-7 clade was characterized by a restricted set of 8 CNAs and that the most divergent subline occupied the position closest to the common ancestor. Expression profiles of 8 MCF-7 sublines were analyzed along with those of 19 unrelated breast cancer cell lines using home made cDNA arrays comprising 720 genes. Hierarchical clustering analysis of the expression data showed that 7/8 MCF-7 sublines were grouped forming a cluster while the remaining subline clustered with unrelated breast cancer cell lines. These data thus showed that MCF-7 sublines differed at both the genomic and phenotypic levels. The analysis of CGH profiles of the parent subline and its three subclones supported the heteroclonal nature of MCF-7 cells. This strongly suggested that the genetic plasticity of MCF-7 cells was related to their intrinsic capacity to generate clonal heterogeneity. We propose that MCF-7, and possibly the breast tumor it was derived from, evolved

Anti-addiction drug ibogaine inhibits voltage-gated ionic currents: A study to assess the drug's cardiac ion channel profile

International Nuclear Information System (INIS)

Koenig, Xaver; Kovar, Michael; Rubi, Lena; Mike, Agnes K.; Lukacs, Peter; Gawali, Vaibhavkumar S.; Todt, Hannes; Hilber, Karlheinz; Sandtner, Walter

2013-01-01

The plant alkaloid ibogaine has promising anti-addictive properties. Albeit not licenced as a therapeutic drug, and despite hints that ibogaine may perturb the heart rhythm, this alkaloid is used to treat drug addicts. We have recently reported that ibogaine inhibits human ERG (hERG) potassium channels at concentrations similar to the drugs affinity for several of its known brain targets. Thereby the drug may disturb the heart's electrophysiology. Here, to assess the drug's cardiac ion channel profile in more detail, we studied the effects of ibogaine and its congener 18-Methoxycoronaridine (18-MC) on various cardiac voltage-gated ion channels. We confirmed that heterologously expressed hERG currents are reduced by ibogaine in low micromolar concentrations. Moreover, at higher concentrations, the drug also reduced human Na v 1.5 sodium and Ca v 1.2 calcium currents. Ion currents were as well reduced by 18-MC, yet with diminished potency. Unexpectedly, although blocking hERG channels, ibogaine did not prolong the action potential (AP) in guinea pig cardiomyocytes at low micromolar concentrations. Higher concentrations (≥ 10 μM) even shortened the AP. These findings can be explained by the drug's calcium channel inhibition, which counteracts the AP-prolonging effect generated by hERG blockade. Implementation of ibogaine's inhibitory effects on human ion channels in a computer model of a ventricular cardiomyocyte, on the other hand, suggested that ibogaine does prolong the AP in the human heart. We conclude that therapeutic concentrations of ibogaine have the propensity to prolong the QT interval of the electrocardiogram in humans. In some cases this may lead to cardiac arrhythmias. - Highlights: • We study effects of anti-addiction drug ibogaine on ionic currents in cardiomyocytes. • We assess the cardiac ion channel profile of ibogaine. • Ibogaine inhibits hERG potassium, sodium and calcium channels. • Ibogaine’s effects on ion channels are a potential

The alteration of the urinary steroid profile under the stress

Directory of Open Access Journals (Sweden)

A Gronowska

2010-03-01

Full Text Available In the second part of twentieth century anabolic-androgenic steroids were introduced into doping practice and received continuously increasing significance. In order to prove the usage of doping substances, the determination of steroid profile in the urine came into practice. Several factors may be responsible for alterations in the normal steroid profile for example age, sex and diet. The aim of this study was to find out, whether the psychological stress may cause modifications in the steroid profile and T/Et ratio. The effect of physical activity was also considered. The steroid profile was determined in the group of 34 students being in non-stress conditions and under stress immediately before an important university exam. The intensity of stress was rated by self-reported questionnaire. The GC/MS method was applied to determine the steroid profile in the urine samples. The results of the experiment have shown that psychological stress may cause significant changes in the steroid profile, especially in females. Physical activity, independently of stress significantly modified the steroid profile. In summary, observed changes in steroid profile suggest, that major fluctuations of T/Et and A/E ratios under the influence of stressogenic factors and physical activity are unlikely.

PES Surface Modification Using Green Chemistry: New Generation of Antifouling Membranes.

Science.gov (United States)

Nady, Norhan

2016-04-18

A major limitation in using membrane-based separation processes is the loss of performance due to membrane fouling. This drawback can be addressed thanks to surface modification treatments. A new and promising surface modification using green chemistry has been recently investigated. This modification is carried out at room temperature and in aqueous medium using green catalyst (enzyme) and nontoxic modifier, which can be safely labelled "green surface modification". This modification can be considered as a nucleus of new generation of antifouling membranes and surfaces. In the current research, ferulic acid modifier and laccase bio-catalyst were used to make poly(ethersulfone) (PES) membrane less vulnerable to protein adsorption. The blank and modified PES membranes are evaluated based on e.g., their flux and protein repellence. Both the blank and the modified PES membranes (or laminated PES on silicon dioxide surface) are characterized using many techniques e.g., SEM, EDX, XPS and SPM, etc. The pure water flux of the most modified membranes was reduced by 10% on average relative to the blank membrane, and around a 94% reduction in protein adsorption was determined. In the conclusions section, a comparison between three modifiers-ferulic acid, and two other previously used modifiers (4-hydroxybenzoic acid and gallic acid)-is presented.

Geoengineering Downwelling Ocean Currents. A Cost Assessment

International Nuclear Information System (INIS)

Zhou, S.; Flynn, P.C.

2005-01-01

Downwelling ocean currents carry carbon into the deep ocean (the solubility pump), and play a role in controlling the level of atmospheric carbon. The formation of North Atlantic Deep Water (NADW) also releases heat to the atmosphere, which is a contributor to a mild climate in Europe. One possible response to the increase in anthropogenic carbon in the atmosphere and to the possible weakening of the NADW is modification of downwelling ocean currents, by an increase in carbon concentration or volume. This study assesses the costs of seven possible methods of modifying downwelling currents, including using existing industrial techniques for exchange of heat between water and air. Increasing carbon concentration in downwelling currents is not practical due to the high degree of saturation of high latitude surface water. Two of the methods for increasing the volume of downwelling currents were found to be impractical, and four were too expensive to warrant further consideration. Formation of thicker sea ice by pumping ocean water onto the surface of ice sheets is the least expensive of the methods identified for enhancing downwelling ocean currents. Modifying downwelling ocean currents is highly unlikely to ever be a competitive method of sequestering carbon in the deep ocean, but may find future application for climate modification

Fitting of the Thomson scattering density and temperature profiles on the COMPASS tokamak

International Nuclear Information System (INIS)

Stefanikova, E.; Peterka, M.; Bohm, P.; Bilkova, P.; Aftanas, M.; Urban, J.; Hron, M.; Panek, R.; Sos, M.

2016-01-01

A new technique for fitting the full radial profiles of electron density and temperature obtained by the Thomson scattering diagnostic in H-mode discharges on the COMPASS tokamak is described. The technique combines the conventionally used modified hyperbolic tangent function for the edge transport barrier (pedestal) fitting and a modification of a Gaussian function for fitting the core plasma. Low number of parameters of this combined function and their straightforward interpretability and controllability provide a robust method for obtaining physically reasonable profile fits. Deconvolution with the diagnostic instrument function is applied on the profile fit, taking into account the dependence on the actual magnetic configuration.

Fitting of the Thomson scattering density and temperature profiles on the COMPASS tokamak

Energy Technology Data Exchange (ETDEWEB)

Stefanikova, E. [Institute of Plasma Physics of the CAS, Za Slovankou 1782/3, 180 00 Prague (Czech Republic); Division of Fusion Plasma Physics, KTH Royal Institute of Technology, SE-10691 Stockholm (Sweden); Peterka, M. [Institute of Plasma Physics of the CAS, Za Slovankou 1782/3, 180 00 Prague (Czech Republic); MFF Charles University, V Holešovičkách 2, 180 00 Prague 8 (Czech Republic); Bohm, P., E-mail: bohm@ipp.cas.cz; Bilkova, P.; Aftanas, M.; Urban, J.; Hron, M.; Panek, R. [Institute of Plasma Physics of the CAS, Za Slovankou 1782/3, 180 00 Prague (Czech Republic); Sos, M. [Institute of Plasma Physics of the CAS, Za Slovankou 1782/3, 180 00 Prague (Czech Republic); Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Břehová 7, 115 19 Prague 1 (Czech Republic)

2016-11-15

A new technique for fitting the full radial profiles of electron density and temperature obtained by the Thomson scattering diagnostic in H-mode discharges on the COMPASS tokamak is described. The technique combines the conventionally used modified hyperbolic tangent function for the edge transport barrier (pedestal) fitting and a modification of a Gaussian function for fitting the core plasma. Low number of parameters of this combined function and their straightforward interpretability and controllability provide a robust method for obtaining physically reasonable profile fits. Deconvolution with the diagnostic instrument function is applied on the profile fit, taking into account the dependence on the actual magnetic configuration.

Statistical theory of wave propagation and multipass absorption for current drive in Tokamaks

International Nuclear Information System (INIS)

Moreau, D.; Litaudon, X.

1993-07-01

The effect of ray stochasticity on the multipass absorption of lower-hybrid waves, used to drive current in tokamaks, is considered. In toroidal geometry, stochasticity arises as an intrinsic property of the Hamiltonian ray trajectories for lower-hybrid waves. Based on the wave kinetic equation, a diffusion equation is derived, with damping and sources, for the wave energy density in the stochastic layer. This equation is solved simultaneously with the electron Fokker-Planck equation to describe the quasilinear flattening of the electron distribution function and the subsequent modification of the wave damping. It is shown that the spectral gap is filled in a self-regulating manner, so that the boundaries of the diffused wave spectrum are independent of the level of ray stochastic diffusion. A simple model for the self-consistent wave spectrum and the radial profile of absorbed power is proposed

Profile modifications in laser-driven temperature fronts using flux-limiters and delocalization models

Science.gov (United States)

Colombant, Denis; Manheimer, Wallace; Busquet, Michel

2004-11-01

A simple steady-state model using flux-limiters by Day et al [1] showed that temperature profiles could formally be double-valued. Stability of temperature profiles in laser-driven temperature fronts using delocalization models was also discussed by Prasad and Kershaw [2]. We have observed steepening of the front and flattening of the maximum temperature in laser-driven implosions [3]. Following the simple model first proposed in [1], we solve for a two-boundary value steady-state heat flow problem for various non-local heat transport models. For the more complicated models [4,5], we obtain the steady-state solution as the asymptotic limit of the time-dependent solution. Solutions will be shown and compared for these various models. 1.M.Day, B.Merriman, F.Najmabadi and R.W.Conn, Contrib. Plasma Phys. 36, 419 (1996) 2.M.K.Prasad and D.S.Kershaw, Phys. Fluids B3, 3087 (1991) 3.D.Colombant, W.Manheimer and M.Busquet, Bull. Amer. Phys. Soc. 48, 326 (2003) 4.E.M.Epperlein and R.W.Short, Phys. Fluids B3, 3092 (1991) 5.W.Manheimer and D.Colombant, Phys. Plasmas 11, 260 (2004)

Shipboard Acoustic Current Profiling during the Coastal Ocean Dynamics Experiment,

Science.gov (United States)

1985-05-01

average profile based on the bottori depth estimated from the ship’s posit ion. in the CODEU region. an efficient computer routine was developed for... forex ~and and( port ward comnport ent s of V. at conistant z ., the depth Iill ships coordi- nlatv (’S(Chap 2). The data cort- from I -mintIe

Polysaccharides from Traditional Chinese Medicines: Extraction, Purification, Modification, and Biological Activity

Directory of Open Access Journals (Sweden)

Yun Chen

2016-12-01

Full Text Available Traditional Chinese Medicine (TCM has been used to treat diseases in China for thousands of years. TCM compositions are complex, using as their various sources plants, animals, fungi, and minerals. Polysaccharides are one of the active and important ingredients of TCMs. Polysaccharides from TCMs exhibit a wide range of biological activities in terms of immunity- modifying, antiviral, anti-inflammatory, anti-oxidative, and anti-tumor properties. With their widespread biological activities, polysaccharides consistently attract scientist's interests, and the studies often concentrate on the extraction, purification, and biological activity of TCM polysaccharides. Currently, numerous studies have shown that the modification of polysaccharides can heighten or change the biological activities, which is a new angle of polysaccharide research. This review highlights the current knowledge of TCM polysaccharides, including their extraction, purification, modification, and biological activity, which will hopefully provide profound insights facilitating further research and development.

Acoustic Doppler current profiler applications used in rivers and estuaries by the U.S. Geological Survey

Science.gov (United States)

Gotvald, Anthony J.; Oberg, Kevin A.

2009-01-01

The U.S. Geological Survey (USGS) has collected streamflow information for the Nation's streams since 1889. Streamflow information is used to predict floods, manage and allocate water resources, design engineering structures, compute water-quality loads, and operate water-control structures. The current (2007) size of the USGS streamgaging network is over 7,400 streamgages nationwide. The USGS has progressively improved the streamgaging program by incorporating new technologies and techniques that streamline data collection while increasing the quality of the streamflow data that are collected. The single greatest change in streamflow measurement technology during the last 100 years has been the development and application of high frequency acoustic instruments for measuring streamflow. One such instrument, the acoustic Doppler current profiler (ADCP), is rapidly replacing traditional mechanical current meters for streamflow measurement (Muste and others, 2007). For more information on how an ADCP works see Simpson (2001) or visit http://hydroacoustics.usgs.gov/. The USGS has used ADCPs attached to manned or tethered boats since the mid-1990s to measure streamflow in a wide variety of conditions (fig. 1). Recent analyses have shown that ADCP streamflow measurements can be made with similar or greater accuracy, efficiency, and resolution than measurements made using conventional current-meter methods (Oberg and Mueller, 2007). ADCPs also have the ability to measure streamflow in streams where traditional current-meter measurements previously were very difficult or costly to obtain, such as streams affected by backwater or tides. In addition to streamflow measurements, the USGS also uses ADCPs for other hydrologic measurements and applications, such as computing continuous records of streamflow for tidally or backwater affected streams, measuring velocity fields with high spatial and temporal resolution, and estimating suspended-sediment concentrations. An overview

The Bootstrap Current and Neutral Beam Current Drive in DIII-D

International Nuclear Information System (INIS)

Politzer, P.A.

2005-01-01

Noninductive current drive is an essential part of the implementation of the DIII-D Advanced Tokamak program. For an efficient steady-state tokamak reactor, the plasma must provide close to 100% bootstrap fraction (f bs ). For noninductive operation of DIII-D, current drive by injection of energetic neutral beams [neutral beam current drive (NBCD)] is also important. DIII-D experiments have reached ∼80% bootstrap current in stationary discharges without inductive current drive. The remaining current is ∼20% NBCD. This is achieved at β N [approximately equal to] β p > 3, but at relatively high q 95 (∼10). In lower q 95 Advanced Tokamak plasmas, f bs ∼ 0.6 has been reached in essentially noninductive plasmas. The phenomenology of high β p and β N plasmas without current control is being studied. These plasmas display a relaxation oscillation involving repetitive formation and collapse of an internal transport barrier. The frequency and severity of these events increase with increasing β, limiting the achievable average β and causing modulation of the total current as well as the pressure. Modeling of both bootstrap and NBCD currents is based on neoclassical theory. Measurements of the total bootstrap and NBCD current agree with calculations. A recent experiment based on the evolution of the transient voltage profile after an L-H transition shows that the more recent bootstrap current models accurately describe the plasma behavior. The profiles and the parametric dependences of the local neutral beam-driven current density have not yet been compared with theory

Surface profile gradient in amorphous Ta{sub 2}O{sub 5} semi conductive layers regulates nanoscale electric current stability

Energy Technology Data Exchange (ETDEWEB)

Cefalas, A.C., E-mail: ccefalas@eie.gr [National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48 Vassileos Constantinou Avenue, Athens 11635 (Greece); Kollia, Z.; Spyropoulos-Antonakakis, N.; Gavriil, V. [National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48 Vassileos Constantinou Avenue, Athens 11635 (Greece); Christofilos, D.; Kourouklis, G. [Physics Division, School of Technology, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece); Semashko, V.V.; Pavlov, V. [Kazan Federal University, Institute of Physics, 18 Kremljovskaja str., Kazan 420008 (Russian Federation); Sarantopoulou, E. [National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48 Vassileos Constantinou Avenue, Athens 11635 (Greece); Kazan Federal University, Institute of Physics, 18 Kremljovskaja str., Kazan 420008 (Russian Federation)

2017-02-28

Highlights: • The work links the surface morphology of amorphous semiconductors with both their electric-thermal properties and current stability at the nanoscale (<1 μm). • Measured high correlation value between surface morphological spatial gradient and conductive electron energy spatial gradient or thermal gradient. • Unidirectional current stability is associated with asymmetric nanodomains along nanosize conductive paths. • Bidirectional current stability is inherent with either long conductive paths or nanosize conductive paths along symmetric nanodomains. • Conclusion: Surface design improves current stability across nanoelectonic junctions. - Abstract: A link between the morphological characteristics and the electric properties of amorphous layers is established by means of atomic, conductive, electrostatic force and thermal scanning microscopy. Using amorphous Ta{sub 2}O{sub 5} (a-Ta{sub 2}O{sub 5}) semiconductive layer, it is found that surface profile gradients (morphological gradient), are highly correlated to both the electron energy gradient of trapped electrons in interactive Coulombic sites and the thermal gradient along conductive paths and thus thermal and electric properties are correlated with surface morphology at the nanoscale. Furthermore, morphological and electron energy gradients along opposite conductive paths of electrons intrinsically impose a current stability anisotropy. For either long conductive paths (L > 1 μm) or along symmetric nanodomains, current stability for both positive and negative currents i is demonstrated. On the contrary, for short conductive paths along non-symmetric nanodomains, the set of independent variables (L, i) is spanned by two current stability/intability loci. One locus specifies a stable state for negative currents, while the other locus also describes a stable state for positive currents.

MARCC (Matrix-Assisted Reader Chromatin Capture): an antibody-free method to enrich and analyze combinatorial nucleosome modifications

Science.gov (United States)

Su, Zhangli

2016-01-01

Combinatorial patterns of histone modifications are key indicators of different chromatin states. Most of the current approaches rely on the usage of antibodies to analyze combinatorial histone modifications. Here we detail an antibody-free method named MARCC (Matrix-Assisted Reader Chromatin Capture) to enrich combinatorial histone modifications. The combinatorial patterns are enriched on native nucleosomes extracted from cultured mammalian cells and prepared by micrococcal nuclease digestion. Such enrichment is achieved by recombinant chromatin-interacting protein modules, or so-called reader domains, which can bind in a combinatorial modification-dependent manner. The enriched chromatin can be quantified by western blotting or mass spectrometry for the co-existence of histone modifications, while the associated DNA content can be analyzed by qPCR or next-generation sequencing. Altogether, MARCC provides a reproducible, efficient and customizable solution to enrich and analyze combinatorial histone modifications. PMID:26131849

Flux consumption, current ramp-up and current diffusion in Tore Supra non-inductive Lower Hybrid scenarios

International Nuclear Information System (INIS)

Kazarian, F.; Litaudon, X.; Moreau, D.; Arslanbekov, R.; Hoang, G.T.; Joffrin, E.; Peysson, Y.; Allibert, J.P.; Ane, J.M.; Bremond, S.

1995-01-01

The main objective of the Lower Hybrid (LH) experiments performed on Tore Supra is to provide large flux savings for long pulse operation while controlling the plasma current density profile. This goal will be best achieved by applying LH wave directly during the current ramp-up phase. Experiments have been performed where a large fraction of the current is driven non-inductively during the ramp-up phase. A theoretical flux consumption scaling is presented and compared to experimental data. The time evolutions of the current density profiles are analysed with a new current diffusion code (CRONOS). In view to achieve fully non-inductive current drive discharges in a fast, systematic and reproducible way, experiments where the primary voltage is imposed have been carried out. In a complementary approach, an appropriate transformer flux feedback scheme has been also studied. (author) 6 refs.; 6 figs

Analysis of Modifications on a Spark Ignition Engine for Operation with Natural Gas

Directory of Open Access Journals (Sweden)

Ramasamy D.

2016-01-01

Full Text Available Transportation is one of the key contributors to petroleum usage and emissions to the atmosphere. According to researchers, there are many ways to use transport by using renewable energy sources. Of these solutions, the immediate solution which requires less modification to current engine technology is by using gaseous fuels. Natural gas is the fuel of choice for minor modification to current engines. As it can be derived from anaerobic digestion process, the potential as a renewable energy source is tremendous, especially for an agricultural country such a Malaysia. The aim in the future will be operating an engine with natural gas only with pipelines straight to houses for easy filling. The fuel is light and can be easily carried in vehicles when in compressed form. As such, Compressed Natural Gas (CNG is currently used in bi-fuel engines, but is mostly not optimized in term of their performance. The focus of the paper is to optimize a model of natural gas engine by one dimensional flow modeling for operation with natural gas. The model is analyzed for performance and emission characteristics produced by a gasoline engine and later compared with natural gas. The average performance drop is about 15% from its gasoline counterpart. The 4% benchmark indicates that the modification to ignition timing and compression ratio does improve engine performance using natural gas as fuel.

Genetic modification and genetic determinism

Science.gov (United States)

Resnik, David B; Vorhaus, Daniel B

2006-01-01

In this article we examine four objections to the genetic modification of human beings: the freedom argument, the giftedness argument, the authenticity argument, and the uniqueness argument. We then demonstrate that each of these arguments against genetic modification assumes a strong version of genetic determinism. Since these strong deterministic assumptions are false, the arguments against genetic modification, which assume and depend upon these assumptions, are therefore unsound. Serious discussion of the morality of genetic modification, and the development of sound science policy, should be driven by arguments that address the actual consequences of genetic modification for individuals and society, not by ones propped up by false or misleading biological assumptions. PMID:16800884

Genetic modification and genetic determinism

Directory of Open Access Journals (Sweden)

Vorhaus Daniel B

2006-06-01

Full Text Available Abstract In this article we examine four objections to the genetic modification of human beings: the freedom argument, the giftedness argument, the authenticity argument, and the uniqueness argument. We then demonstrate that each of these arguments against genetic modification assumes a strong version of genetic determinism. Since these strong deterministic assumptions are false, the arguments against genetic modification, which assume and depend upon these assumptions, are therefore unsound. Serious discussion of the morality of genetic modification, and the development of sound science policy, should be driven by arguments that address the actual consequences of genetic modification for individuals and society, not by ones propped up by false or misleading biological assumptions.

Modeling streamflow from coupled airborne laser scanning and acoustic Doppler current profiler data

Science.gov (United States)

Norris, Lam; Kean, Jason W.; Lyon, Steve

2016-01-01

The rating curve enables the translation of water depth into stream discharge through a reference cross-section. This study investigates coupling national scale airborne laser scanning (ALS) and acoustic Doppler current profiler (ADCP) bathymetric survey data for generating stream rating curves. A digital terrain model was defined from these data and applied in a physically based 1-D hydraulic model to generate rating curves for a regularly monitored location in northern Sweden. Analysis of the ALS data showed that overestimation of the streambank elevation could be adjusted with a root mean square error (RMSE) block adjustment using a higher accuracy manual topographic survey. The results of our study demonstrate that the rating curve generated from the vertically corrected ALS data combined with ADCP data had lower errors (RMSE = 0.79 m3/s) than the empirical rating curve (RMSE = 1.13 m3/s) when compared to streamflow measurements. We consider these findings encouraging as hydrometric agencies can potentially leverage national-scale ALS and ADCP instrumentation to reduce the cost and effort required for maintaining and establishing rating curves at gauging station sites similar to the Röån River.

Proteomic profiling of exosomes: Current perspectives

DEFF Research Database (Denmark)

Simpson, Richard J; Jensen, Søren S; Lim, Justin W E

2008-01-01

for the spread of morphogens in epithelia. The advent of current MS-based proteomic technologies has contributed significantly to our understanding of the molecular composition of exosomes. In addition to a common set of membrane and cytosolic proteins, it is becoming increasingly apparent that exosomes harbor...... distinct subsets of proteins that may be linked to cell-type associated functions. The secretion of exosomes by tumor cells and their implication in the transport and propagation of infectious cargo such as prions and retroviruses such as HIV suggest their participation in pathological situations...

Accommodating for plant modifications

International Nuclear Information System (INIS)

Weirich, P.H.

1977-01-01

Modification to a nuclear power plant may have different causes: 1) new instructions by the authorities; 2) changes of the marginal conditions on the construction site; 3) progress in the technological development. - Examples from different plants are supposed to demonstrate how such changes influence the planning or the construction and how they are integrated in the process of preparation. A distinction can be made between modifications before the completion of the submission of the order, during the phase of preparatory planning and during the construction phase. Of great importance are especially modifications made after the beginning of the construction works, since, in general, there is little scope for technical modifications and since consequences for the time schedule are to be expected. (orig.) [de

Biomaterials modification by ion beam

International Nuclear Information System (INIS)

Zhang Tonghe; Yi Zhongzhen; Zhang Xu; Wu Yuguang

2001-01-01

Ion beam technology is one of best ways for the modification of biomaterials. The results of ion beam modification of biomaterials are given. The method and results of improved biocompatibility are indicated by ion beam technology. The future development of ion beam modification of biomaterials is discussed

Current profile control and magnetohydrodynamic stability in Tore Supra discharges with edge-plasma control by the ergodic divertor

International Nuclear Information System (INIS)

Zabiego, M.; Friant, C.; Ghendrih, P.; Becoulet, M.; Bucalossi, J.; Saint-Laurent, F.

1999-01-01

Although ergodic divertors are primarily designed to control particle and heat fluxes at the plasma edge, they also happen to affect the MHD stability of tokamak discharges. On Tore Supra, the ergodic divertor has long been known to stabilize the m/n=2/1 tearing mode induced, for instance, by edge radiation and detachment processes, thus allowing safe high-current and high-density operations. More recently, though, in discharges where ergodic divertor operations were optimised relative to the control of the edge-plasma (i.e., with large divertor perturbation), a detrimental increase in the disruptiveness has been observed. The action that the ergodic divertor has on the MHD activity is interpreted in terms of a redistribution of the current profile. The latter results from a large increase in the edge resistivity, primarily induced by the degradation of the electron energy confinement in the ergodic layer. The possibility that a transport barrier develops in the vicinity of the separatrix strongly affects the considered modelling. (authors)

Safety of modifications at nuclear power plants - the role of minor modifications and human and organisational factors

International Nuclear Information System (INIS)

2005-01-01

Operating experience repeatedly shows that changes and modifications at nuclear power plants (NPPs) may lead to safety significant events. At the same time, modifications are necessary to ensure a safe and economic functioning of the NPPs. To ensure safety in all plant configurations it is important that modification processes are given proper attention both by the utilities and the regulators. The operability, maintainability and testability of every modification should be thoroughly assessed from different points of view to ensure that no safety problems are introduced. The OECD/NEA Committee on Safety of Nuclear Installations (CSNI) has recently addressed the issue of modifications by organising a 'Workshop on Modifications at Nuclear Power Plants Operating Experience, Safety Significance and Role of Human Factors'. This workshop was undertaken as a joint effort of the Working Group on Operating Experience (WGOE) and the Special Experts Group on Human and Organisational Factors (SEGHOF), and it was held at the OECD Headquarters in Paris on October 6 to 8, 2003. The initiative to organise the workshop was taken by the WGOE and the SEGHOF based on findings from events and incidents due to modifications at nuclear power plants in the world and weaknesses experienced in modification processes. During the workshop, the WGOE focused on the theme of 'Minor Modifications and their Safety Significance', while the SEGHOF focused on the topic 'Human and Organisational Factors in NPP Modifications'. This report is based on material collected before the workshop, the workshop proceedings, discussions of the group of experts responsible for the arrangement of the workshop, and additional material collected by a consultant. The workshop was preceded by extensive preparations, which included collection of national surveys in response to questionnaires on modifications at the NPPs. Not all of these surveys were available at the workshop, but their findings have now been included

Modification of JRR-2

International Nuclear Information System (INIS)

Miyasaka, Yasuhiko

1978-01-01

This report gives an outline of some of the main modifications carried out around the Reactor Core on the Research Reactor JRR-2, at the Tokai Research Establishment of JAERI. The JRR-2 was shut down in December 1973, to improve it in heavy water leakage from the metal packing between core tank and support ring, corrosion of the lower shielding plug, and fault in the control-rod mechanism. Main modifications were a standing seal weld at the support ring to stop heavy water leakage, replacement of the reactor top shield and improvement of the helium system. The control-rod assemblies and the refueling devices were replaced by the newly designed ones also. In addition to the modification plan, the irradiated air exhaust system was improved to reduce radioactive argon gas release through the stack. Works were completed successfully in September 1975. But a light water leakage occurred at the stand pipe below the light water tank on November 11, 1975, which was repaired in about 4 months. When considering the operation of above 5,000 hours after the modification, however, the quality of the modification work may be said to be quite satisfactory. The present report in which works to the completion are described may be valuable as a record of reactor modification which is a new experience at JAERI. (auth.)

Knowledge and Practice on lifestyle modifications among males with hypertension

Directory of Open Access Journals (Sweden)

Vanitha Durai

2015-03-01

Full Text Available Background: In 2004, prevalence of hypertension was 25% in urban and 10% in rural population in India, leads to 57% of all stroke deaths and 42% of cardiovascular deaths.(1,2 Life style modifications control hypertension and prevent complications. Aims and Objectives: To find out the level of knowledge about life style modifications needed for control of blood pressure among males with hypertension and their current life style practice. Materials and methods: This cross sectional study was conducted among males with hypertension in the age group of 30-59 years who attended Hypertension Clinic of Medicine Outpatient Department in Sri Ramachandra Medical College and Hospital, Porur, Chennai in November 2013 using an interview schedule. Result: Among 100 males with hypertension, 34% were in the age group of less than 50 years and 64% had hypertension for less than 5 years. Nearly 84% had knowledge about influence of smoking and alcohol on hypertension and 82% had knowledge about at least 3 dietary factors which control hypertension. About 70% of males were aware that more than 30 minutes of physical activity/day is needed to control hypertension. Currently 89% were physically active for more than 30 minutes/day, 72% did not consume alcohol, 89% were nonsmokers but 25% were adding extra salt in their diet and none of them increased fibre intake. Conclusion: Dietary modification practices were less among hypertensive males.

In-situ kinetics of modifications induced by swift heavy ions in Al2O3: Colour centre formation, structural modification and amorphization

International Nuclear Information System (INIS)

Grygiel, C.; Moisy, F.; Sall, M.; Lebius, H.; Balanzat, E.; Madi, T.; Been, T.; Marie, D.; Monnet, I.

2017-01-01

This paper details in-situ studies of modifications induced by swift heavy ion irradiation in α-Al2O3. This complex behaviour is intermediary between the behaviour of amorphizable and non-amorphizable materials, respectively. A unique combination of irradiation experiments was performed at the IRRSUD beam line of the GANIL facility, with three different characterisation techniques: in-situ UV–Vis absorption, in-situ grazing incidence X-Ray diffraction and ex-situ transmission electron microscopy. This allows a complete study of point defects, and by depth profile of structural and microstructural modifications created on the trajectory of the incident ion. The α-Al2O3 crystals have been irradiated by 92 MeV Xenon and 74 MeV Krypton ions, the irradiation conditions have been chosen rather similar with an energy range where the ratio between electronic and nuclear stopping power changes dramatically as function of depth penetration. The main contribution of electronic excitation, above the threshold for track formation, is present beneath the surface to finally get almost only elastic collisions at the end of the projected range. Amorphization kinetics by the overlapping of multiple ion tracks is observed. In the crystalline matrix, long range strains, unit-cell swelling, local microstrain, domain size decrease, disordering of oxygen sublattice as well as colour centre formation are found. This study highlights the relationship between ion energy losses into a material and its response. While amorphization requires electronic stopping values above a certain threshold, point defects are predominantly induced by elastic collisions, while some structural modifications of the crystalline matrix, such as unit-cell swelling, are due to contribution of both electronic and nuclear processes.

Stimulating the addicted brain : The effects of transcranial direct current stimulation and cognitive bias modification in alcohol users

NARCIS (Netherlands)

den Uyl, T.E.

2017-01-01

In this PhD project we investigated a new intervention in which we combined brain stimulation with cognitive training. We used a form of training called cognitive bias modification (CBM) aimed at retraining dysfunctional automatic reactions towards alcohol. We investigated whether transcranial

Permit application modifications

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-11-01

This document contains the Permit Application Modifications for the Y-12 Industrial Landfill V site on the Oak Ridge Reservation. These modifications include the assessment of stability of the proposed Landfill V under static and loading conditions. Analyses performed include the general slope stability, veneer stability of the bottom liner and cover system, and a liquefaction potential assessment of the foundation soils.

Permit application modifications

International Nuclear Information System (INIS)

1995-11-01

This document contains the Permit Application Modifications for the Y-12 Industrial Landfill V site on the Oak Ridge Reservation. These modifications include the assessment of stability of the proposed Landfill V under static and loading conditions. Analyses performed include the general slope stability, veneer stability of the bottom liner and cover system, and a liquefaction potential assessment of the foundation soils

Calculation of pole profiles for the design of particle accelerators magnets. Equivalent current and conformal representation methods; Calcul de profils polaires destines a des aimants d'accelerateurs de particules. Methode des courants et methode des transformations conformes

Energy Technology Data Exchange (ETDEWEB)

Jaidane, S [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1968-04-01

These two methods allow the determination of the shape of the poles in magnets, for a given field distribution in the air-gap. First method: The principle of the method consists to create the desired law of field by means of current sheets in which one can adjust the density given in a polynomial form. For the right distribution of these currents, the equipotential corresponding to the magnetic potential of the excitation coils is calculated. The pole profile of the H or C magnet identified with this equipotential line will finally take the place of the distribution of the current sheets used in the calculation. Steel permeability is assumed to be infinite and Foucault current effects are neglected in the case of variable fields. Second method: It consists to find a conformal representation that maps the pole profile plane upon the upper half of another plane where the equipotentials are two half straight lines, and where the field problems are easier to solve. Steel permeability is also considered to be infinite and the coils far from the pole faces. This known method has been applied to be compared with the first one. (author) [French] Ces deux methodes consistent a determiner la forme des pieces polaires d'aimants pour une distribution de champ determinee a l'avance dans l'entrefer. Premiere methode: Le principe de la methode consiste a creer la loi de champ desiree par l'intermediaire de nappes de courant dont on peut ajuster la densite exprimee sous une forme polynominale. Pour une distribution convenable de ces courants, on calcule l'equipotentielle correspondant au potentiel magnetique des bobines d'excitation. Le profil polaire d'un aimant en H ou C identifie a l'equipotentielle se substitue finalement a la repartition des nappes de courant utilisee dans la methode de calcul. La permeabilite de l'acier est supposee infinie et les courants de Foucault sont negliges dans le cas des champs variables. Seconde methode: Elle consiste a trouver une transformation

The third generation multi-purpose plasma immersion ion implanter for surface modification of materials

CERN Document Server

Tang Bao Yin; Wang Xiao Feng; Gan Kong Yin; Wang Song Yan; Chu, P K; Huang Nian Ning; Sun Hong

2002-01-01

The third generation multi-purpose plasma immersion ion implantation (PIII) equipment has been successfully used for research and development of surface modification of biomedical materials, metals and their alloys in the Southwest Jiaotong University. The implanter equipped with intense current, pulsed cathodic arc metal plasma sources which have both strong coating function and gas and metal ion implantation function. Its pulse high voltage power supply can provide big output current. It can acquire very good implantation dose uniformity. The equipment can both perform ion implantation and combine ion implantation with sputtering deposition and coating to form many kinds of synthetic surface modification techniques. The main design principles, features of important components and achievement of research works in recent time have been described

Profiling of Histone Post-Translational Modifications in Mouse Brain with High-Resolution Top-Down Mass Spectrometry

Energy Technology Data Exchange (ETDEWEB)

Zhou, Mowei; Paša-Tolić, Ljiljana; Stenoien, David L.

2016-12-21

Histones play central roles in most chromosomal functions and both their basic biology and roles in disease have been the subject of intense study. Since multiple PTMs along the entire protein sequence are potential regulators of histones, a top-down approach, where intact proteins are analyzed, is ultimately required for complete characterization of proteoforms. However, significant challenges remain for top-down histone analysis primarily because of deficiencies in separation/resolving power and effective identification algorithms. Here, we used state of the art mass spectrometry and a bioinformatics workflow for targeted data analysis and visualization. The workflow uses ProMex for intact mass deconvolution, MSPathFinder as search engine, and LcMsSpectator as a data visualization tool. ProMex sums across retention time to maximize sensitivity and accuracy for low abundance species in MS1deconvolution. MSPathFinder searches the MS2 data against protein sequence databases with user-defined modifications. LcMsSpectator presents the results from ProMex and MSPathFinder in a format that allows quick manual evaluation of critical attributes for high-confidence identifications. When complemented with the open-modification tool TopPIC, this workflow enabled identification of novel histone PTMs including tyrosine bromination on histone H4 and H2A, H3 glutathionylation, and mapping of conventional PTMs along the entire protein for many histone subunits.

Behavior Modification in Coaching.

Science.gov (United States)

Lynch, Annette Rutt; Stillman, Stephen M.

1979-01-01

An example of behavior modification used in athletic coaching is presented. The case study involves a member of a women's basketball team and details the use of behavior modification for both weight reduction and skill improvement. (JMF)

Towards Selective Tidal-Stream Transport for Lagrangian profilers

DEFF Research Database (Denmark)

Jouffroy, Jerome; Zhou, Qiuyang; Zielinski, Oliver

2011-01-01

Autonomous Lagrangian profilers are widely used as measurement and monitoring platforms. In their current mode of operation, the profilers usually drift passively at their parking depth before making a vertical profile to go back to the surface. This paper presents a control strategy to actively...

Ninth international conference on ion beam modification of materials. Book of abstracts

International Nuclear Information System (INIS)

1995-01-01

The conference focused on new developments and current status in the use of ion beams for modification of materials including: fundamental ion beam research and secondary effects of ion beams; materials modifications and techniques; biomedical and industrial applications; low energy processes; point defects and damage, nanocrystals in insulators, plasma immersion ion implantation, molecular dynamics simulations of ion-surface interactions, ion-beam mixing of insulators, GeV ion irradiation, electro-optical materials, polymers, tribological materials, and semiconductor processing. The handbook contains the workshop's program, abstracts and an author index. Separate abstracts were prepared for all papers in this volume

Ninth international conference on ion beam modification of materials. Book of abstracts

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-12-31

The conference focused on new developments and current status in the use of ion beams for modification of materials including: fundamental ion beam research and secondary effects of ion beams; materials modifications and techniques; biomedical and industrial applications; low energy processes; point defects and damage, nanocrystals in insulators, plasma immersion ion implantation, molecular dynamics simulations of ion-surface interactions, ion-beam mixing of insulators, GeV ion irradiation, electro-optical materials, polymers, tribological materials, and semiconductor processing. The handbook contains the workshop`s program, abstracts and an author index. Separate abstracts were prepared for all papers in this volume.

Anatomy of a turbidity current: Concentration and grain size structure of a deep-sea flow revealed by multiple-frequency acoustic profilers

Science.gov (United States)

Simmons, S.; Parsons, D. R.; Paull, C. K.; Barry, J.; Chaffey, M. R.; Gwiazda, R.; O'Reilly, T. C.; Maier, K. L.; Rosenberger, K. J.; Talling, P.; Xu, J.

2017-12-01

Turbidity currents are responsible for transporting large volumes of sediment to the deep ocean, yet remain poorly understood due to the limited number of field observations of these episodic, high energy events. As part of the Monterey Coordinated Canyon Experiment high resolution, sub-minute acoustic velocity and backscatter profiles were acquired with downward-looking acoustic Doppler current profilers (ADCPs) distributed along the canyon on moorings at depths ranging from 270 to 1,900 m over a period of 18 months. Additionally, three upward-looking ADCPs on different frequencies (300, 600 and 1200 kHz) profiled the water column above a seafloor instrument node (SIN) at 1850 m water depth. Traps on the moorings collected sediment carried by the flows at different heights above the seafloor and sediment cores were taken to determine the depositional record produced by the flows. Several sediment-laden turbidity flows were observed during the experiment, three of which ran out for more than 50 km to water depths of greater than 1,900 m and were observed on all of the moorings. Flow speeds of up to 6 m/s were observed and individual moorings, anchored by railroad wheels, moved up to 7.8 km down-canyon during these powerful events. We present results based on a novel analysis of the multiple-frequency acoustic data acquired by the ADCPs at the SIN integrated with grain size data from the sediment traps, close to the deepest mooring in the array where the flow thickened to the 70 m height of the ADCP above the bed. The analysis allows, for the first time, retrieval of the suspended sediment concentration and vertical distribution of grain size structure within a turbidity in spectacular detail. The details of the stratification and flow dynamics will be used to re-evaluate and discuss our existing models for these deep-sea flows.

Profile relaxation and tilt instability in a field-reversed configuration

International Nuclear Information System (INIS)

Ohtani, H.; Horiuchi, R.; Sato, T.

2003-01-01

The profile relaxation from a magnetic hydrodynamic (MHD) profile to a kinetic equilibrium in field-reversed configurations (FRCs) is investigated by two-dimensional electromagnetic particle simulation. The radial oscillation takes place in order to relax an excess energy in the MHD profile, and the system spontaneously relaxes toward a kinetic equilibrium. In this kinetic equilibrium, the hollow electron current profile is realized as a result of the combined effects of the single particle orbits and the ion finite Larmor radius, and the ion current profile becomes peaked due to the effect of the ion meandering motion. Three-dimensional full electromagnetic particle simulation is also performed to study the stability of these kinetic equilibrium against the tilt mode. The growth rate of the tilt instability is reduced by the kinetic effects. It is found that the stabilization effect of tilt mode becomes much distinct when the current density changes from the peaked profile to the hollow one. (author)

Profile relaxation and tilt instability in a field-reversed configuration

International Nuclear Information System (INIS)

Ohtani, H.; Horiuchi, R.; Sato, T.

2002-10-01

The profile relaxation from a magnetohydrodynamic (MHD) profile to a kinetic equilibrium in field-reversed configurations (FRCs) is investigated by two-dimensional electromagnetic particle simulation. The radial oscillation takes place in order to relax an excess energy in the MHD profile, and the system spontaneously relaxes toward a kinetic equilibrium. In this kinetic equilibrium, the hollow electron current profile is realized as a result of the combined effects of the single particle orbits and the ion finite Larmor radius, and the ion current profile becomes peaked due to the effect of the ion meandering motion. Three-dimensional full electromagnetic particle simulation is also performed to study the stability of these kinetic equilibrium against the tilt mode. The growth rate of the tilt instability is reduced by the kinetic effects. It is found that the stabilization effect of tilt mode becomes much distinct when the current density changes from the peaked profile to the hollow one. (author)

Profile relaxation and tilt instability in a field-reversed configuration

International Nuclear Information System (INIS)

Ohtani, H.; Horiuchi, R.; Sato, T.

2002-01-01

The profile relaxation from a magnetichydrodynamic (MHD) profile to a kinetic equilibrium in field-reversed configurations (FRCs) in investigated by two-dimensional electromagnetic particle simulation. The radial oscillation takes place in order to relax an excess energy in the MHD profile, and the system spontaneously relaxes toward a kinetic equilibrium. In this kinetic equilibrium, the hollow electron current profile is realized as a result of the combined effects of the single particle orbits and the ion finite Larmor radius, and the ion current profile becomes peaked due to the effect of the ion meandering motion. Three-dimensional full electromagnetic particle simulations is also performed to study the stability of these kinetic equilibrium against the tilt mode. The growth rate of the tilt instability is reduced by the kinetic is effects. It is found that the stabilization effect of tilt mode becomes much distinct when the current density changes from the peaked profile to the hollow one. (author)

Implicit User Interest Profile

CERN Document Server

Chan, K

2002-01-01

User interest profile presents items that the users are interested in. Typically those items can be listed or grouped. Listing is good but it does not possess interests at different abstraction levels - the higher-level interests are more general, while the lower-level ones are more specific. Furthermore, more general interests, in some sense, correspond to longer-term interests, while more specific interests correspond to shorter-term interests. This hierarchical user interest profile has obvious advantages: specifying user's specific interests and general interests and representing their relationships. Current user interest profile structures mostly do not use implicit method, nor use an appropriate clustering algorithm especially for conceptually hierarchical structures. This research studies building a hierarchical user interest profile (HUIP) and the hierarchical divisive algorithm (HDC). Several users visit hundreds of web pages and each page is recorded in each users profile. These web pages are used t...

Enzymatic Modification of Sphingomyelin

DEFF Research Database (Denmark)

Due to its major role in maintaining the water-retaining properties of the epidermis, ceramide is of great commercial potential in cosmetic and pharmaceuticals such as hair and skin care products. Currently, chemical synthesis of ceramide is a costly process, and developments of alternative cost......-efficient, high yield production methods are of great interest. In the present study, the potential of producing ceramide through the enzymatic hydrolysis of sphingomyelin have been studied. sphingomyelin is a ubiquitous membrane-lipid and rich in dairy products or by-products. It has been verified...... that sphingomyelin modification gives a feasible approach to the potential production of ceramide. The reaction system has been improved through system evaluation and the optimization of several important factors, and phospholipase C from Clostridium perfringens shows higher activity towards the hydrolysis reaction...

Crystal modifications and dissolution rate of piroxicam.

Science.gov (United States)

Lyn, Lim Yee; Sze, Huan Wen; Rajendran, Adhiyaman; Adinarayana, Gorajana; Dua, Kamal; Garg, Sanjay

2011-12-01

Piroxicam is a nonsteroidal anti-inflammatory drug with low aqueous solubility which exhibits polymorphism. The present study was carried out to develop polymorphs of piroxicam with enhanced solubility and dissolution rate by the crystal modification technique using different solvent mixtures prepared with PEG 4000 and PVP K30. Physicochemical characteristics of the modified crystal forms of piroxicam were investigated by X-ray powder diffractometry, FT-IR spectrophotometry and differential scanning calorimetry. Dissolution and solubility profiles of each modified crystal form were studied and compared with pure piroxicam. Solvent evaporation method (method I) produced both needle and cubic shaped crystals. Slow crystallization from ethanol with addition of PEG 4000 or PVP K30 at room temperature (method II) produced cubic crystal forms. Needle forms produced by method I improved dissolution but not solubility. Cubic crystals produced by method I had a dissolution profile similar to that of untreated piroxicam but showed better solubility than untreated piroxicam. Cubic shaped crystals produced by method II showed improved dissolution, without a significant change in solubility. Based on the XRPD results, modified piroxicam crystals obtained by method I from acetone/benzene were cube shaped, which correlates well with the FTIR spectrum; modified needle forms obtained from ethanol/methanol and ethanol/acetone showed a slight shift of FTIR peak that may be attributed to differences in the internal structure or conformation.

Mobile Phone Cognitive Bias Modification Research Platform for Substance Use Disorders: Protocol for a Feasibility Study.

Science.gov (United States)

Zhang, Melvyn; Ying, JiangBo; Song, Guo; Fung, Daniel Ss; Smith, Helen

2018-06-12

Cognitive biases refer to automatic attentional and interpretational tendencies, which could be retained by cognitive bias modification interventions. Cristea et al and Jones et al have published reviews (in 2016 and 2017 respectively) on the effectiveness of such interventions. The advancement of technologies such as electronic health (eHealth) and mobile health (mHealth) has led to them being harnessed for the delivery of cognitive bias modification. To date, at least eight studies have demonstrated the feasibility of mobile technologies for the delivery of cognitive bias modification. Most of the studies are limited to a description of the conventional cognitive bias modification methodology that has been adopted. None of the studies shared the developmental process for the methodology involved, such that future studies could adopt it in the cost-effective replication of such interventions. It is important to have a common platform that could facilitate the design and customization of cognitive bias modification interventions for a variety of psychiatric and addictive disorders. It is the aim of the current research protocol to describe the design of a research platform that allows for customization of cognitive bias modification interventions for addictive disorders. A multidisciplinary team of 2 addiction psychiatrists, a psychologist with expertise in cognitive bias modification, and a computer engineer, were involved in the development of the intervention. The proposed platform would comprise of a mobile phone version of the cognitive bias task which is controlled by a server that could customize the algorithm for the tasks and collate the reaction-time data in realtime. The server would also allow the researcher to program the specific set of images that will be present in the task. The mobile phone app would synchronize with the backend server in real-time. An open-sourced cross-platform gaming software from React Native was used in the current development

Pulsed glow discharge mass spectrometry for molecular depth profiling of polymers

International Nuclear Information System (INIS)

Lobo, L.; Pereiro, R.; Sanz-Medel, A.; Bordel, N.; Pisonero, J.; Licciardello, A.; Tuccitto, N.; Tempez, A.; Chapon, P.

2009-01-01

Full text: Nowadays thin films of polymeric materials involve a wide range of industrial applications, so techniques capable of providing in-depth profile information are required. Most of the techniques available for this purpose are based on the use of energetic particle beams which interact with polymers producing undesirable physicochemical modifications. Radiofrequency pulsed glow discharge (rf-pulsed-GD) coupled to time-of-flight mass spectrometry (TOFMS) could afford the possibility of acquiring both elemental and molecular information creating minimal damage to surfaces and thereby obtaining depth profiles. This work will evaluate rf-GDs coupled to an orthogonal TOFMS for direct analysis of polymers. (author)

Modification of surfaces and surface layers by non equilibrium processes

International Nuclear Information System (INIS)

Beamson, G.; Brennan, W.J.; Clark, D.T.; Howard, J.

1988-01-01

Plasmas are examples of non-equilibrium phenomena which are being used increasingly for the synthesis and modification of materials impossible by conventional routes. This paper introduces methods available by describing the construction and characteristics of some equipment used for the production of different types of plasmas and other non-equilibrium phenomena. This includes high energy ion beams. The special features, advantages and disadvantages of the techniques will be described. There are a multitude of potential application relevant to electronic, metallic, ceramic, and polymeric materials. However, scale-up from the laboratory to production equipment depends on establishing a better understanding of both the physics and chemistry of plasma as well as plasma-solid interactions. Examples are given of how such an understanding can be gained. The chemical analysis of polymer surfaces undergoing modification by inert gas, hydrogen or oxygen plasmas is shown to give physical information regarding the relative roles of diffusion of active species, and direct and radiative energy transfer from the plasma. Surface modification by plasma depositing a new material onto an existing substrate is discussed with particular reference to the deposition of amorphous carbon films. Applications of the unique properties of these films are outlined together with our current understanding of these properties based on chemical and physical methods of analysis of both the films and the plasmas producing them. Finally, surface modification by ion beams is briefly illustrated using examples from the electronics and metals industries where the modification has had a largely physical rather than chemical effect on the starting material. (orig.)

Effects on physicochemical characteristics of yoghurt and ice cream with fatty acid modification and cholesterol removal

International Nuclear Information System (INIS)

Nadeem, M.; Ullah, R.; Arif, A.M.

2015-01-01

This study investigated the effect of fatty acid modification and cholesterol removal on physico-chemical characteristics of yoghurt and ice cream. Fatty acid profile of milk fat was modified by feeding calcium salts of soybean oil fatty acids to cows and cholesterol was removed by b-cyclodextrin b-cyclodextrin removed 76% and 60% cholesterol from yoghurt and ice cream. Modification of fatty acid composition did not have a significant effect on a-tocopherol content; while b-cyclodextrin treated milk had substantially lower a-tocopherol content. The concentration of a-tocopherol in control and b-cyclodextrin treated yoghurt was 45.62, 32.73 mg/g and 210.34, 185.56 mg/g for ice cream, respectively. Fatty acid modification and cholesterol removal significantly decreased the overrun in ice cream (P<0.05), with no effect on sensory characteristics of yoghurt and ice cream. These results evidenced that milk with higher content of unsaturated fatty acids and low cholesterol can be used in the formulation of yoghurt and ice cream with improved health benefits and suitable sensory features. (author)

Impact of magnetic shear modification on confinement and turbulent fluctuations in LHD plasmas

International Nuclear Information System (INIS)

Fukuda, T.; Tamura, N.; Ida, K.

2008-10-01

For the comprehensive understandings of transport phenomena in toroidal confinement systems and improvement of the predictive capability of burning plasmas in ITER, the impact of magnetic shear has been extensively investigated in the Large Helical Device (LHD) for comparison with tokamaks. Consequently, it was heuristically documented that the pronounced effect of magnetic shear, which has been hitherto considered to be ubiquitous and strongly impacts the core transport in the tokamak experiments, is not quite obvious. Namely, the kinetic profiles respond little under extensive modification of the magnetic shear in the core, although the local transport analysis indicates the sign of improvement in confinement transiently when the magnetic shear is reduced. It was thereby concluded that the magnetic shear in the core strongly influences the MHD activity, but it may only be one of the necessary conditions for the transport reduction, and some other crucial knobs, such as the density gradient or T e /T i ratio, would have to be simultaneously controlled. The low wavenumber turbulence seems to be suppressed under the weak shear, and the turbulent fluctuation intensity behaves in a consistent manner as a whole, following the conventional paradigm accumulated in the negative shear experiments in tokamaks. However, vigorous dynamics of turbulent fluctuations have occasionally been observed under the magnetic shear modification, which respond in much faster time scale than the characteristic time scale for either the magnetic diffusion or the profile evolution. (author)

Parent Prevention Communication Profiles and Adolescent Substance Use: A Latent Profile Analysis and Growth Curve Model

Science.gov (United States)

Choi, Hye Jeong; Miller-Day, Michelle; Shin, YoungJu; Hecht, Michael L.; Pettigrew, Jonathan; Krieger, Janice L.; Lee, JeongKyu; Graham, John W.

2017-01-01

This current study identifies distinct parent prevention communication profiles and examines whether youth with different parental communication profiles have varying substance use trajectories over time. Eleven schools in two rural school districts in the Midwestern United States were selected, and 784 students were surveyed at three time points from the beginning of 7th grade to the end of 8th grade. A series of latent profile analyses were performed to identify discrete profiles/subgroups of substance-specific prevention communication (SSPC). The results revealed a 4-profile model of SSPC: Active-Open, Passive-Open, Active-Silent, and Passive-Silent. A growth curve model revealed different rates of lifetime substance use depending on the youth’s SSPC profile. These findings have implications for parenting interventions and tailoring messages for parents to fit specific SSPC profiles. PMID:29056872

Quantification and Analysis of Suspended Sediments Concentration Using Mobile and Static Acoustic Doppler Current Profiler Instruments

Directory of Open Access Journals (Sweden)

Angga Dwinovantyo

2017-01-01

Full Text Available The application of Acoustic Doppler Current Profiler (ADCP can be used not only for measuring ocean currents, but also for quantifying suspended sediment concentrations (SSC from acoustic backscatter strength based on sonar principle. Suspended sediment has long been recognized as the largest sources of sea contaminant and must be considered as one of the important parameters in water quality of seawater. This research was to determine SSC from measured acoustic backscattered intensity of static and mobile ADCP. In this study, vertically mounted 400 kHz and 750 kHz static ADCP were deployed in Lembeh Strait, North Sulawesi. A mobile ADCP 307.2 kHz was also mounted on the boat and moved to the predefined cross-section, accordingly. The linear regression analysis of echo intensity measured by ADCP and by direct measurement methods showed that ADCP is a reliable method to measure SSC with correlation coefficient (r 0.92. Higher SSC was observed in low water compared to that in high water and near port area compared to those in observed areas. All of this analysis showed that the combination of static and mobile ADCP methods produces reasonably good spatial and temporal data of SSC.

Changes in serum lipid profile of obese or overweight children and adolescents following a lifestyle modification course

Directory of Open Access Journals (Sweden)

Roya Kelishadi

2012-10-01

Full Text Available BACKGROUND: Considering rapid global increase in children obesity and high prevalence of dyslipidemia in obese and overweight children, this study aimed to evaluate the effect of an educational course on changes of lipid profile in children.    METHODS: This non-pharmacological clinical trial study was performed on 4-18 year-old children attending outpatient clinics of Isfahan Endocrine and Metabolism Research Center (Iran. Anthropometric measurements were conducted for all children. Fasting blood samples were taken from right hand of the participants at the first laboratory visit. Biochemical tests including measurement of total cholesterol (TC, triglyceride (TG, high-density lipoprotein cholesterol (HDL-C and low-density lipoprotein cholesterol (LDL-C were also carried out. Children took part in one educational session in which they were taught about ways and benefits of having regular physical activity once a day and having healthy foods. All children were followed up for about four months and anthropometrics and biochemical tests were repeated. Data was analyzed using SPSS16.    RESULTS: A total number of 412 children (245 girls and 167 boys were divided into four age groups of under 6, 6-9, 10-13, and 14-18 years old. Baseline anthropometric measures were significantly higher in boys. However, there was no difference between boys and girls in baseline lipid profile. Children's body mass index (BMI z-score increased in all age groups except for 14-18 year-old boys. In boys older than 10 years, there were significant reductions in LDL-C and TC. In girls over 10 years of age, there was a significant increase in HDL-C. Although anthropometric measurements did not change in children (except for 14-18 year-old-boys, there was a significant reduction in children's lipid profile after the study.    CONCLUSION: Our study showed that although one session of interventional education had no significant effects on children's anthropometric

Proteomic Investigation of Protein Profile Changes and Amino Acid Residue Level Modification in Cooked Lamb Meat: The Effect of Boiling.

Science.gov (United States)

Yu, Tzer-Yang; Morton, James D; Clerens, Stefan; Dyer, Jolon M

2015-10-21

Hydrothermal treatment (heating in water) is a common method of general food processing and preparation. For red-meat-based foods, boiling is common; however, how the molecular level effects of this treatment correlate to the overall food properties is not yet well-understood. The effects of differing boiling times on lamb meat and the resultant cooking water were here examined through proteomic evaluation. The longer boiling time was found to result in increased protein aggregation involving particularly proteins such as glyceraldehyde-3-phosphate dehydrogenase, as well as truncation in proteins such as in α-actinin-2. Heat-induced protein backbone cleavage was observed adjacent to aspartic acid and asparagine residues. Side-chain modifications of amino acid residues resulting from the heating, including oxidation of phenylalanine and formation of carboxyethyllysine, were characterized in the cooked samples. Actin and myoglobin bands from the cooked meat per se remained visible on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, even after significant cooking time. These proteins were also found to be the major source of observed heat-induced modifications. This study provides new insights into molecular-level modifications occurring in lamb meat proteins during boiling and a protein chemistry basis for better understanding the effect of this common treatment on the nutritional and functional properties of red-meat-based foods.

Mechanisms of the negative synergy effect between electron cyclotron current drive and lower hybrid current drive in tokamak

International Nuclear Information System (INIS)

Chen Shaoyong; Hong Binbin; Tang Changjian; Yang Wen; Zhang Xinjun

2013-01-01

The synergy current drive by combining electron cyclotron wave (ECW) with lower hybrid wave (LHW) can be used to either increase the noninductive current drive efficiency or shape the plasma current profile. In this paper, the synergy current drive by ECW and LHW is studied with numerical simulation. The nonlinear relationship between the wave powers and the synergy current of ECW and LHW is revealed. When the LHW power is small, the synergy current reduces as the ECW power increases, and the synergy current is even reduced to lower than zero, which is referred as negative synergy in the this context. Research shows that the mechanism of the negative synergy is the peaking effect of LHW power profile and the trapped electrons effect. The present research is helpful for understanding the physics of synergy between electron cyclotron current drive and lower hybrid current drive, it can also instruct the design of experiments. (authors)

Effects of Computer-Based Training on Procedural Modifications to Standard Functional Analyses

Science.gov (United States)

Schnell, Lauren K.; Sidener, Tina M.; DeBar, Ruth M.; Vladescu, Jason C.; Kahng, SungWoo

2018-01-01

Few studies have evaluated methods for training decision-making when functional analysis data are undifferentiated. The current study evaluated computer-based training to teach 20 graduate students to arrange functional analysis conditions, analyze functional analysis data, and implement procedural modifications. Participants were exposed to…

Mass spectrometric identification of isocyanate-induced modifications of keratins in human skin

NARCIS (Netherlands)

Hulst, A.G.; Verstappen, D.R.W.; Riet-van Oeveren, D. van der; Vermeulen, N.P.E.; Noort, D.

2015-01-01

In the current paper we show that exposure of human callus to isocyanates leads to covalent modifications within keratin proteins. Mass spectrometric analyses of pronase digests of keratin isolated from exposed callus show that both mono- and di-adducts (for di-isocyanates) are predominantly formed

Electron beam induced modification of grafted polyamides

International Nuclear Information System (INIS)

Timus, D.M.; Brasoveanu, M.M.; Bradley, D.A.; Popov, A.M.

1998-01-01

It is well known that irradiation, when applied on its own or in combination with other physical and chemical treatments, can manifest in radiation damage to materials. Radiation processing technology focuses upon producing favourable modification of materials through use of relatively high dose and dose rates. Current interest is in modifying the thermal and electrical properties of textured polymers in an effort to improve safety and wear comfort of clothing. No less important is the production of textiles which are safe to use, both in homes and offices. Present investigations provide additional data in support of findings which show that polyamides, a particular class of textured polymer, are amenable to radiation processing. Accelerated electron beam irradiation of sheets of polyamide fibre results in induced grafting of acrylic and methacrylic acids. The degree of grafting is critically dependent upon irradiation dose and the extent of monomers dilution. Of particular importance is the high correlation which is found between degree of grafting and a decrease in the softening rate of the modified polyamide. A systematic modification of electrical conductivity is also observed. (author)

Modifications to HFEF/S for IFR fuel cycle demonstration

International Nuclear Information System (INIS)

Lineberry, M.J.; Phipps, R.D.; Forrester, R.J.; Carnes, M.D.; Rigg, R.H.

1988-01-01

Modifications have begun to the Hot Fuel Examination Facility-South (HFEF/S) in order to demonstrate the technology of the integral fast reactor (IFR) fuel cycle. This paper describes the status of the modifications to the facility and briefly reviews the status of the development of the process equipment. The HFEF/S was the demonstration facility for the early Experimental Breeder Reactor II (EBR-II) melt refining/injection-casting fuel cycle. Then called the Fuel Cycle Facility, ∼400 EBR-II fuel assemblies were recycled in the two hot cells of the facility during the 1964-69 period. Since then it has been utilized as a fuels examination facility. The objective of the IFR fuel cycle program is to upgrade HFEF/S to current standards, install new process equipment, and demonstrate the commercial feasibility of the IFR pyroprocess fuel cycle

Particle transport analysis in lower hybrid current drive discharges of JT-60U

International Nuclear Information System (INIS)

Nagashima, K.; Ide, S.; Naito, O.

1996-01-01

Particle transport is modified in lower hybrid current drive discharges of JT-60U. The density profile becomes broad during the lower hybrid wave injection and the profile change depends on the injected wave spectrum. Particle transport coefficients (diffusion coefficient and profile peaking factor) were evaluated using gas-puff modulation experiments. The diffusion coefficient in the current drive discharges is about three times larger than in the ohmic discharges. The profile peaking factor decreases in the current drive discharges and the evaluated values are consistent with the measured density profiles. (author)

Sm2Fe17Nx with discontinuous nitrogen profiles

International Nuclear Information System (INIS)

Skomski, R.; Kobayashi, K.; Brennan, S.; Coey, J.M.D.

1995-01-01

Microprobe analysis and theoretical calculations based on Hooke's law are used to investigate Sm 2 Fe 17 N x nitrides produced by N 2 and NH 3 interstitial modification. In the case of molecular nitrogen, stress and strain as well as Curie temperature, magnetization and anisotropy exhibit a smooth spatial variation, while nitrogen overloading due to the presence of ammonia leads to large excess strain and lattice incoherency. Discontinuous nitrogen profiles are associated with the occurrence of microcracks. ((orig.))

Temporal characteristics of coherent flow structures generated over alluvial sand dunes, Mississippi River, revealed by acoustic doppler current profiling and multibeam echo sounding

Science.gov (United States)

Czuba, John A.; Oberg, Kevin A.; Best, Jim L.; Parsons, Daniel R.; Simmons, S. M.; Johnson, K.K.; Malzone, C.

2009-01-01

This paper investigates the flow in the lee of a large sand dune located at the confluence of the Mississippi and Missouri Rivers, USA. Stationary profiles collected from an anchored boat using an acoustic Doppler current profiler (ADCP) were georeferenced with data from a real-time kinematic differential global positioning system. A multibeam echo sounder was used to map the bathymetry of the confluence and provided a morphological context for the ADCP measurements. The flow in the lee of a low-angle dune shows good correspondence with current conceptual models of flow over dunes. As expected, quadrant 2 events (upwellings of low-momentum fluid) are associated with high backscatter intensity. Turbulent events generated in the lower lee of a dune near the bed are associated with periods of vortex shedding and wake flapping. Remnant coherent structures that advect over the lower lee of the dune in the upper portion of the water column, have mostly dissipated and contribute little to turbulence intensities. The turbulent events that occupy most of the water column in the upper lee of the dune are associated with periods of wake flapping.

Turbulent Flow Modification With Thermoacoustic Waves for Separation Control

Science.gov (United States)

2017-08-24

respectively. At the outlet, the time-average flow is set to be the target state of the sponge zone. In this section, the effects of momentum thickness...Turbulent Flow Modification With Thermoacoustic Waves For Separation Control The views, opinions and/or findings contained in this report are those...currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. Florida State University Sponsored Research Administration 874

Evidence for Anomalous Effects on the Current Evolution in Tokamak Operating Scenarios

Energy Technology Data Exchange (ETDEWEB)

Casper, T; Jayakumar, R; Allen, S; Holcomb, C; Makowski, M; Pearlstein, L; Berk, H; Greenfield, C; Luce, T; Petty, C; Politzer, P; Wade, M; Murakami, M; Kessel, C

2006-10-03

Alternatives to the usual picture of advanced tokamak (AT) discharges are those that form when anomalous effects alter the plasma current and pressure profiles and those that achieve stationary characteristics through mechanisms so that a measure of desired AT features is maintained without external current-profile control. Regimes exhibiting these characteristics are those where the safety factor (q) evolves to a stationary profile with the on-axis and minimum q {approx} 1 and those with a deeply hollow current channel and high values of q. Operating scenarios with high fusion performance at low current and where the inductively driven current density achieves a stationary configuration with either small or non-existing sawteeth may enhance the neutron fluence per pulse on ITER and future burning plasmas. Hollow current profile discharges exhibit high confinement and a strong ''box-like'' internal transport barrier (ITB). We present results providing evidence for current profile formation and evolution exhibiting features consistent with anomalous effects or with self-organizing mechanisms. Determination of the underlying physical processes leading to these anomalous effects is important for scaling of current experiments for application in future burning plasmas.

Advanced Design Mixer Pump Tank 18 Design Modifications Summary Report

International Nuclear Information System (INIS)

Adkins, B.J.

2002-01-01

The Westinghouse Savannah River Company (WSRC) is preparing to retrieve high level waste (HLW) from Tank 18 in early FY03 to provide feed for the Defense Waste Processing Facility (DWPF) and to support tank closure in FY04. As part of the Tank 18 project, WSRC will install a single Advanced Design Mixer Pump (ADMP) in the center riser of Tank 18 to mobilize, suspend, and mix radioactive sludge in preparation for transfer to Tank 7. The use of a single ADMP is a change to the current baseline of four (4) standard slurry pumps used during previous waste retrieval campaigns. The ADMP was originally conceived by Hanford and supported by SRS to provide a more reliable and maintainable mixer pump for use throughout the DOE complex. The ADMP underwent an extensive test program at SRS between 1998 and 2002 to assess reliability and hydraulic performance. The ADMP ran for approximately 4,200 hours over the four-year period. A detailed tear down and inspection of the pump following the 4,2 00-hour run revealed that the gas mechanical seals and anti-friction bearings would need to be refurbished/replaced prior to deployment in Tank 18. Design modifications were also needed to meet current Authorization Basis safety requirements. This report documents the modifications made to the ADMP in support of Tank 18 deployment. This report meets the requirements of Tanks Focus Area (TFA) Milestone 3591.4-1, ''Issue Report on Modifications Made to the ADMP,'' contained in Technical Task Plan (TTP) SR16WT51, ''WSRC Retrieval and Closure.''

Optimized profiles for improved confinement and stability in the Dill-D tokamak

International Nuclear Information System (INIS)

Taylor, T.S.; St John, H.; Turnbull, A.D.

1994-01-01

Simultaneous achievement of high energy confinement, τ E , and high plasma beta, β, leads to an economically attractive compact tokamak fusion reactor. High confinement enhancement, H τ E /τ E -ITER89P 4, and high normalized beta β N β/(I/aB) = 6%-m-T/MA. have been obtained in DIII-D experimental discharges. These improved confinement and/or improved stability limits are observed in several DIII-D high performance operational regimes: VH-mode, high l i H-mode, second stable core, and high beta poloidal. We have identified several important features of the improved performance in these discharges: details of the plasma shape, toroidal rotation or ExB flow profile, q profile and current density profile, and pressure profile. From our improved physics understanding of these enhanced performance regimes, we have developed operational scenarios which maintain the essential features of the improved confinement and which increase the stability limits using localized current profile control. The stability limit is increased by modifying the interior safety factor profile to be nonmonotonic with high central q, while maintaining the edge current density consistent with the improved transport regimes and the high edge bootstrap current. We have calculated high beta equilibria with β N 6.5, stable to ideal n=1 kinks and stable to ideal ballooning modes. The safety factor at the 95% flux surface is 6, the central q value is 3.9 and the minimum in q is 2.6. The current density profile is maintained by the natural profile of the bootstrap current, and a modest amount of electron cyclotron current drive. (Author)

Optimized profiles for improved confinement and stability in the DIII-D tokamak

International Nuclear Information System (INIS)

Taylor, T.S.; St. John, H.; Turnbull, A.D.

1995-02-01

Simultaneous achievement of high energy confinement, τ E , and high plasma beta, β, leads to an economically attractive compact tokamak fusion reactor. High confinement enhancement, H = τ E /τ E-ITER89P = 4, and high normalized beta β N = β/(I/aB) = 6%-m-T/MA, have been obtained in DIII-D experimental discharges. These improved confinement and/or improved stability limits are observed in several DIII-D high performance operational regimes: VH-mode, high ell i H-mode, second stable core, and high beta poloidal. The authors have identified several important features of the improved performance in these discharges: details of the plasma shape, toroidal rotation or ExB flow profile, q profile and current density profile, and pressure profile. From the improved physics understanding of these enhanced performance regimes, they have developed operational scenarios which maintain the essential features of the improved confinement and which increase the stability limits using localized current profile control. The stability limit is increased by modifying the interior safety factor profile to be nonmonotonic with high central q, while maintaining the edge current density consistent with the improved transport regimes and the high edge bootstrap current. They have calculated high beta equilibria with β N = 6.5, stable to ideal n = 1 kinks and stable to ideal ballooning modes. The safety factor at the 95% flux surface is 6, the central q value is 3.9 and the minimum in q is 2.6. The current density profile is maintained by the natural profile of the bootstrap current, and a modest amount of electron cyclotron current drive

The management of modifications

International Nuclear Information System (INIS)

Bernard, C.

1992-01-01

Description of the management methods of modifications at EDF. To maintain safety standards of the nuclear power station the 'Direction de l'Equipment' and the 'Direction du Parc en Exploitation' have jointly fixed the modalities of management for all modifications and recorded them in a 'Practical Guide'

The NNR requirements to address modification, modernization, refurbishment and ageing management

International Nuclear Information System (INIS)

Thugwane, Samuel

2013-01-01

The National Nuclear Regulator (NNR) is a national competent authority in South African which has been mandated under Act 47 of 1999 to provide for the protection of property people and environment. The NNR achieves its mandated by issuing Nuclear Authorisations in case of Nuclear Installations and Certificate of registration for the mining industry. Currently SAFARI-1 Research Reactor at Pelindaba site is the only Research Reactor that is licensed by NNR through a Process based licensing. SAFARI-1 is a 20 MW research reactor and has been in operation since 1965 and is approaching its full lifetime. Regular, periodic and systematic examination, inspection, maintenance and testing of all plant, systems, structures and components have been developed and implemented. Modification and refurbishment has been implemented over years since its construction. Ageing of structural components and obsolescence is now becoming a challenge; as a result, Ageing Management Programme has been developed to address these issues. In accordance with the NNR requirements any modification that the licensee plan to implement, must comply with NNR approved processes and procedures relating to control of such modification to the design of existing plant, facility or system design, including modifications that may be of a temporary nature

PES Surface Modification Using Green Chemistry: New Generation of Antifouling Membranes

Directory of Open Access Journals (Sweden)

Norhan Nady

2016-04-01

Full Text Available A major limitation in using membrane-based separation processes is the loss of performance due to membrane fouling. This drawback can be addressed thanks to surface modification treatments. A new and promising surface modification using green chemistry has been recently investigated. This modification is carried out at room temperature and in aqueous medium using green catalyst (enzyme and nontoxic modifier, which can be safely labelled “green surface modification”. This modification can be considered as a nucleus of new generation of antifouling membranes and surfaces. In the current research, ferulic acid modifier and laccase bio-catalyst were used to make poly(ethersulfone (PES membrane less vulnerable to protein adsorption. The blank and modified PES membranes are evaluated based on e.g., their flux and protein repellence. Both the blank and the modified PES membranes (or laminated PES on silicon dioxide surface are characterized using many techniques e.g., SEM, EDX, XPS and SPM, etc. The pure water flux of the most modified membranes was reduced by 10% on average relative to the blank membrane, and around a 94% reduction in protein adsorption was determined. In the conclusions section, a comparison between three modifiers—ferulic acid, and two other previously used modifiers (4-hydroxybenzoic acid and gallic acid—is presented.

The NNR requirements to address modification, modernization, refurbishment and ageing management

Energy Technology Data Exchange (ETDEWEB)

Thugwane, Samuel [National Nuclear Regulator, Pretoria (South Africa)

2013-07-01

The National Nuclear Regulator (NNR) is a national competent authority in South African which has been mandated under Act 47 of 1999 to provide for the protection of property people and environment. The NNR achieves its mandated by issuing Nuclear Authorisations in case of Nuclear Installations and Certificate of registration for the mining industry. Currently SAFARI-1 Research Reactor at Pelindaba site is the only Research Reactor that is licensed by NNR through a Process based licensing. SAFARI-1 is a 20 MW research reactor and has been in operation since 1965 and is approaching its full lifetime. Regular, periodic and systematic examination, inspection, maintenance and testing of all plant, systems, structures and components have been developed and implemented. Modification and refurbishment has been implemented over years since its construction. Ageing of structural components and obsolescence is now becoming a challenge; as a result, Ageing Management Programme has been developed to address these issues. In accordance with the NNR requirements any modification that the licensee plan to implement, must comply with NNR approved processes and procedures relating to control of such modification to the design of existing plant, facility or system design, including modifications that may be of a temporary nature.

Simple currents versus orbifolds with discrete torsion -- a complete classification

CERN Document Server

Kreuzer, M

1994-01-01

We give a complete classification of all simple current modular invariants, extending previous results for $(\\Zbf_p)^k$ to arbitrary centers. We obtain a simple explicit formula for the most general case. Using orbifold techniques to this end, we find a one-to-one correspondence between simple current invariants and subgroups of the center with discrete torsions. As a by-product, we prove the conjectured monodromy independence of the total number of such invariants. The orbifold approach works in a straightforward way for symmetries of odd order, but some modifications are required to deal with symmetries of even order. With these modifications the orbifold construction with discrete torsion is complete within the class of simple current invariants. Surprisingly, there are cases where discrete torsion is a necessity rather than a possibility.

Simple currents versus orbifolds with discrete torsion - a complete classification

International Nuclear Information System (INIS)

Kreuzer, M.; Schellekens, A.N.

1993-01-01

We give a complete classification of all simple current modular invariants, extending previous results for (Z p ) k to arbitrary centers. We obtain a simple explicit formula for the most general case. Using orbifold techniques to this end, we find a one-to-one correspondence between simple current invariants and subgroups of the center with discrete torsions. As a by-product, we prove the conjectured monodromy independence of the total number of such invariants. The orbifold approach works in a straightforward way for symmetries of odd order, but some modifications are required to deal with symmetries of even order. With these modifications the orbifold construction with discrete torsion is complete within the class of simple current invariants. Surprisingly, there are cases where discrete torsion is a necessity rather than a possibility. (orig.)

Scaling laws for TEXT plasma profiles

International Nuclear Information System (INIS)

McCool, S.C.; Bravenec, R.V.; Chen, J.Y.; Foster, M.S.; Li, W.L.; Ouroura, A.; Phillips, P.E.; Richards, B.; Wenzel, K.W.; Zhang, Z.M.

1994-01-01

Regression analysis has been performed on a number of measured profiles including temperature and density vs. nominal macroscopic operating parameters for TEXT tokamak (pre-upgrade) ohmic plasmas. The resulting simple empirical model has enabled the authors to quickly approximate profiles of electron temperature and density, ion temperature, and soft x-ray brightness, as well as the scalar quantities: total radiated power, q=1 radius, sawtooth period and amplitude, and energy confinement time as a power law of toroidal field, plasma current, chord average density, and fueling gas atomic weight. The model profiles are only applicable to the plasma interior, i.e. within the limiter radius. In most cases the predicted model profiles are within the experimental error bars of measured profiles and are more accurate at predicting profile variation for small operating parameter changes than the measured profiles

Modulated Current Drive Measurements

International Nuclear Information System (INIS)

Petty, C.C.; Lohr, J.; Luce, T.C.; Prater, R.; Cox, W.A.; Forest, C.B.; Jayakumar, R.J.; Makowski, M.A.

2005-01-01

A new measurement approach is presented which directly determines the noninductive current profile from the periodic response of the motional Stark effect (MSE) signals to the slow modulation of the external current drive source. A Fourier transform of the poloidal magnetic flux diffusion equation is used to analyze the MSE data. An example of this measurement technique is shown using modulated electron cyclotron current drive (ECCD) discharges from the DIII-D tokamak

Proteomic profiling of mitochondria: what does it tell us about the ageing brain?

Science.gov (United States)

Ingram, Thomas; Chakrabarti, Lisa

2016-12-13

Mitochondrial dysfunction is evident in numerous neurodegenerative and age-related disorders. It has also been linked to cellular ageing, however our current understanding of the mitochondrial changes that occur are unclear. Functional studies have made some progress reporting reduced respiration, dynamic structural modifications and loss of membrane potential, though there are conflicts within these findings. Proteomic analyses, together with functional studies, are required in order to profile the mitochondrial changes that occur with age and can contribute to unravelling the complexity of the ageing phenotype. The emergence of improved protein separation techniques, combined with mass spectrometry analyses has allowed the identification of age and cell-type specific mitochondrial changes in energy metabolism, antioxidants, fusion and fission machinery, chaperones, membrane proteins and biosynthesis pathways. Here, we identify and review recent data from the analyses of mitochondria from rodent brains. It is expected that knowledge gained from understanding age-related mitochondrial changes of the brain should lead to improved biomarkers of normal ageing and also age-related disease progression.

Q-profile requirements for electro ITB formation

Energy Technology Data Exchange (ETDEWEB)

Goodman, T. P.; Coda, S.; Henderson, M. A.; Sauter, O.; Behn, R.; Bottino, A.; Fable, E.; Martynov, A.; Nikkola, P.; Zucca, C.

2005-07-01

The formation requirements of ITBs on numerous tokamaks have been correlated with either a power threshold, appearance of a low order rational surface near q{sub m}in or q{sub 9}5, weak or negative shear, etc. On TCV, electron ITBs (eITBs) can be formed during a gradual evolution from a centrally peaked to hollow current profile while all external actuators are held constant. The formation occurs rapidly (<{tau}{sub e}E) and locally and, according to ASTRA modeling, is correlated with the appearance of a local minimum in the q-profile. There is no clear evidence that the minimum in q appears at a low order rational. These eITBs are sustained by non-inductively driven current (ECCD and bootstrap current) while the current in the tokamak transformer is beld constant. Thus, they are not inherently transient but can exist for several current redistribution times; limited only by the pulse length of the gyrotrons. After the barrier is formed, the gransformer coil can be used as a counter (or co-) current source with negligible accompanying input power. The eITB performance can be enhanced (degraded) by altering solely the current or q-profile: when negative (positive) inductive current is driven, the on-axis current density decreases (increases) resulting in a stronger (weaker) reversed shear as both the ECCD and bootstrap currents are peaked off-axis. These experiments provide a unique realm of eITB formation and performance characteristics that can be used to isolate the physics criteria governing the eITB. (Author)

Assessment of modification level of hypoeutectic Al -Si alloys by pattern recognition of cooling curves

Directory of Open Access Journals (Sweden)

CHEN Xiang

2005-11-01

Full Text Available Most evaluations of modification level are done according to a specific scale based on an merican Foundry Society (AFS standard wall chart as qualitative analysis in Al-Si casting production currently. This method is quite dependent on human experience when making comparisons of the microstructure with the standard chart. And the structures depicted in the AFS chart do not always resemble those seen in actual Al-Si castings. Therefore, this ualitativeanalysis procedure is subjective and can introduce human-caused errors into comparative metallographic analyses. A quantization parameter of the modification level was introduced by setting up the relationship between mean area weighted shape factor of eutectic silicon phase and the modification level using image analysis technology. In order to evaluate the modification level, a new method called "intelligent evaluating of melt quality by pattern recognition of hermal analysis cooling curves" has also been introduced. The results show that silicon modification level can be precisely assessed by comparison of the cooling curve of the melt to be evaluated with the one most similar to it in a database.

Protein Expression Modifications in Phage-Resistant Mutants of Aeromonas salmonicida after AS-A Phage Treatment

Directory of Open Access Journals (Sweden)

Catarina Moreirinha

2018-03-01

Full Text Available The occurrence of infections by pathogenic bacteria is one of the main sources of financial loss for the aquaculture industry. This problem often cannot be solved with antibiotic treatment or vaccination. Phage therapy seems to be an alternative environmentally-friendly strategy to control infections. Recognizing the cellular modifications that bacteriophage therapy may cause to the host is essential in order to confirm microbial inactivation, while understanding the mechanisms that drive the development of phage-resistant strains. The aim of this work was to detect cellular modifications that occur after phage AS-A treatment in A. salmonicida, an important fish pathogen. Phage-resistant and susceptible cells were subjected to five successive streak-plating steps and analysed with infrared spectroscopy, a fast and powerful tool for cell study. The spectral differences of both populations were investigated and compared with a phage sensitivity profile, obtained through the spot test and efficiency of plating. Changes in protein associated peaks were found, and these results were corroborated by 1-D electrophoresis of intracellular proteins analysis and by phage sensitivity profiles. Phage AS-A treatment before the first streaking-plate step clearly affected the intracellular proteins expression levels of phage-resistant clones, altering the expression of distinct proteins during the subsequent five successive streak-plating steps, making these clones recover and be phenotypically more similar to the sensitive cells.

Anti-addiction drug ibogaine inhibits voltage-gated ionic currents: A study to assess the drug's cardiac ion channel profile

Energy Technology Data Exchange (ETDEWEB)

Koenig, Xaver; Kovar, Michael; Rubi, Lena; Mike, Agnes K.; Lukacs, Peter; Gawali, Vaibhavkumar S.; Todt, Hannes [Center for Physiology and Pharmacology, Department of Neurophysiology and -pharmacology, Medical University of Vienna, 1090 Vienna (Austria); Hilber, Karlheinz, E-mail: karlheinz.hilber@meduniwien.ac.at [Center for Physiology and Pharmacology, Department of Neurophysiology and -pharmacology, Medical University of Vienna, 1090 Vienna (Austria); Sandtner, Walter [Center for Physiology and Pharmacology, Institute of Pharmacology, Medical University of Vienna, 1090 Vienna (Austria)

2013-12-01

The plant alkaloid ibogaine has promising anti-addictive properties. Albeit not licenced as a therapeutic drug, and despite hints that ibogaine may perturb the heart rhythm, this alkaloid is used to treat drug addicts. We have recently reported that ibogaine inhibits human ERG (hERG) potassium channels at concentrations similar to the drugs affinity for several of its known brain targets. Thereby the drug may disturb the heart's electrophysiology. Here, to assess the drug's cardiac ion channel profile in more detail, we studied the effects of ibogaine and its congener 18-Methoxycoronaridine (18-MC) on various cardiac voltage-gated ion channels. We confirmed that heterologously expressed hERG currents are reduced by ibogaine in low micromolar concentrations. Moreover, at higher concentrations, the drug also reduced human Na{sub v}1.5 sodium and Ca{sub v}1.2 calcium currents. Ion currents were as well reduced by 18-MC, yet with diminished potency. Unexpectedly, although blocking hERG channels, ibogaine did not prolong the action potential (AP) in guinea pig cardiomyocytes at low micromolar concentrations. Higher concentrations (≥ 10 μM) even shortened the AP. These findings can be explained by the drug's calcium channel inhibition, which counteracts the AP-prolonging effect generated by hERG blockade. Implementation of ibogaine's inhibitory effects on human ion channels in a computer model of a ventricular cardiomyocyte, on the other hand, suggested that ibogaine does prolong the AP in the human heart. We conclude that therapeutic concentrations of ibogaine have the propensity to prolong the QT interval of the electrocardiogram in humans. In some cases this may lead to cardiac arrhythmias. - Highlights: • We study effects of anti-addiction drug ibogaine on ionic currents in cardiomyocytes. • We assess the cardiac ion channel profile of ibogaine. • Ibogaine inhibits hERG potassium, sodium and calcium channels. • Ibogaine’s effects on

Human Rights and Behavior Modification

Science.gov (United States)

Roos, Philip

1974-01-01

Criticisms of behavior modification, which charge that it violates ethical and legal principles, are discussed and reasons are presented to explain behavior modification's susceptibility to attack. (GW)

Centrifugal compressor shape modification using a proposed inverse design method

International Nuclear Information System (INIS)

Niliahmadabadi, Mahdi; Poursadegh, Farzad

2013-01-01

This paper is concerned with a quasi-3D design method for the radial and axial diffusers of a centrifugal compressor on the meridional plane. The method integrates a novel inverse design algorithm, called ball-spine algorithm (BSA), and a quasi-3D analysis code. The Euler equation is solved on the meridional plane for a numerical domain, of which unknown boundaries (hub and shroud) are iteratively modified under the BSA until a prescribed pressure distribution is reached. In BSA, unknown walls are composed of a set of virtual balls that move freely along specified directions called spines. The difference between target and current pressure distributions causes the flexible boundary to deform at each modification step. In validating the quasi-3D analysis code, a full 3D Navier-Stokes code is used to analyze the existing and designed compressors numerically. Comparison of the quasi-3D analysis results with full 3D analysis results shows viable agreement. The 3D numerical analysis of the current compressor shows a huge total pressure loss on the 90 .deg. bend between the radial and axial diffusers. Geometric modification of the meridional plane causes the efficiency to improve by about 10%.

Centrifugal compressor shape modification using a proposed inverse design method

Energy Technology Data Exchange (ETDEWEB)

Niliahmadabadi, Mahdi [Isfahan University of Technology, Isfahan (Iran, Islamic Republic of); Poursadegh, Farzad [Sharif University of Technology, Tehran (Iran, Islamic Republic of)

2013-03-15

This paper is concerned with a quasi-3D design method for the radial and axial diffusers of a centrifugal compressor on the meridional plane. The method integrates a novel inverse design algorithm, called ball-spine algorithm (BSA), and a quasi-3D analysis code. The Euler equation is solved on the meridional plane for a numerical domain, of which unknown boundaries (hub and shroud) are iteratively modified under the BSA until a prescribed pressure distribution is reached. In BSA, unknown walls are composed of a set of virtual balls that move freely along specified directions called spines. The difference between target and current pressure distributions causes the flexible boundary to deform at each modification step. In validating the quasi-3D analysis code, a full 3D Navier-Stokes code is used to analyze the existing and designed compressors numerically. Comparison of the quasi-3D analysis results with full 3D analysis results shows viable agreement. The 3D numerical analysis of the current compressor shows a huge total pressure loss on the 90 .deg. bend between the radial and axial diffusers. Geometric modification of the meridional plane causes the efficiency to improve by about 10%.

Surface glycosylation profiles of urine extracellular vesicles.

Directory of Open Access Journals (Sweden)

Jared Q Gerlach

Full Text Available Urinary extracellular vesicles (uEVs are released by cells throughout the nephron and contain biomolecules from their cells of origin. Although uEV-associated proteins and RNA have been studied in detail, little information exists regarding uEV glycosylation characteristics. Surface glycosylation profiling by flow cytometry and lectin microarray was applied to uEVs enriched from urine of healthy adults by ultracentrifugation and centrifugal filtration. The carbohydrate specificity of lectin microarray profiles was confirmed by competitive sugar inhibition and carbohydrate-specific enzyme hydrolysis. Glycosylation profiles of uEVs and purified Tamm Horsfall protein were compared. In both flow cytometry and lectin microarray assays, uEVs demonstrated surface binding, at low to moderate intensities, of a broad range of lectins whether prepared by ultracentrifugation or centrifugal filtration. In general, ultracentrifugation-prepared uEVs demonstrated higher lectin binding intensities than centrifugal filtration-prepared uEVs consistent with lesser amounts of co-purified non-vesicular proteins. The surface glycosylation profiles of uEVs showed little inter-individual variation and were distinct from those of Tamm Horsfall protein, which bound a limited number of lectins. In a pilot study, lectin microarray was used to compare uEVs from individuals with autosomal dominant polycystic kidney disease to those of age-matched controls. The lectin microarray profiles of polycystic kidney disease and healthy uEVs showed differences in binding intensity of 6/43 lectins. Our results reveal a complex surface glycosylation profile of uEVs that is accessible to lectin-based analysis following multiple uEV enrichment techniques, is distinct from co-purified Tamm Horsfall protein and may demonstrate disease-specific modifications.

Theory and discretization of ideal magnetohydrodynamic equilibria with fractal pressure profiles

Science.gov (United States)

Kraus, B. F.; Hudson, S. R.

2017-09-01

In three-dimensional ideal magnetohydrodynamics, closed flux surfaces cannot maintain both rational rotational-transform and pressure gradients, as these features together produce unphysical, infinite currents. A proposed set of equilibria nullifies these currents by flattening the pressure on sufficiently wide intervals around each rational surface. Such rational surfaces exist at every scale, which characterizes the pressure profile as self-similar and thus fractal. The pressure profile is approximated numerically by considering a finite number of rational regions and analyzed mathematically by classifying the irrational numbers that support gradients into subsets. Applying these results to a given rotational-transform profile in cylindrical geometry, we find magnetic field and current density profiles compatible with the fractal pressure.

Differential N-glycan patterns identified in lung adenocarcinoma by N-glycan profiling of formalin-fixed paraffin-embedded (FFPE) tissue sections.

Science.gov (United States)

Wang, Xiaoning; Deng, Zaian; Huang, Chuncui; Zhu, Tong; Lou, Jiatao; Wang, Lin; Li, Yan

2018-02-10

N-glycan profiling is a powerful approach for analyzing the functional relationship between N-glycosylation and cancer. Current methods rely on either serum or fresh tissue samples; however, N-glycan patterns may differ between serum and tissue, as the proteins of serum originate from a variety of tissues. Furthermore, fresh tissue samples are difficult to ship and store. Here, we used a profiling method based on formalin-fixed paraffin-embedded (FFPE) tissue sections from lung adenocarcinoma patients. We found that our method was highly reproducible. We identified 58 N-glycan compositions from lung adenocarcinoma FFPE samples, 51 of which were further used for MS n -based structure prediction. We show that high mannose type N-glycans are upregulated, while sialylated N-glycans are downregulated in our FFPE lung adenocarcinoma samples, compared to the control samples. Our receiver operating characteristic (ROC) curve analysis shows that high mannose type and sialylated N-glycans are useful discriminators to distinguish between lung adenocarcinoma and control tissue. Together, our results indicate that expression levels of specific N-glycans correlate well with lung adenocarcinoma, and strongly suggest that our FFPE-based method will be useful for N-glycan profiling of cancer tissues. Glycosylation is one of the most important post-translational protein modifications, and is associated with several physiopathological processes, including carcinogenesis. In this study, we tested the feasibility of using formalin-fixed paraffin-embedded (FFPE) tissue sections to identify changes in N-glycan patterns and identified the differentially expressed N-glycans of lung adenocarcinoma. Our study shows that the FFPE-based N-glycan profiling method is useful for clinical diagnosis as well as identification of potential biomarkers, and our data expand current knowledge of differential N-glycan patterns of lung adenocarcinoma. Copyright © 2017 Elsevier B.V. All rights reserved.

Non-inductive current drive experiments on DIII-D, and future plans

International Nuclear Information System (INIS)

Prater, R.; Austin, M.; Baity, F.W.; Callis, R.W.; Chiu, S.C.; DeGrassie, J.S.; Freeman, R.L.; Forest, C.B.; Goulding, R.H.; Harvey, R.W.; Hoffman, D.J.; Ikezi, H.; Lohr, J.; James, R.A.; Kupfer, K.; Lin-Liu, Y.R.; Luce, T.C.; Moeller, C.P.; Petty, C.C.; Pinsker, R.I.; Porkolab, M.; Squire, J.; Trukhin, V.

1995-01-01

Experiments on DIII-D (and other tokamaks) have shown that improved performance can follow from optimization of the current density profile. Increased confinement of energy and a higher limit on β have both been found in discharges in which the current density profile is modified through transient means, such as ramping of current or elongation. Peaking of the current distribution to obtain discharges with high internal inductance l i has been found to be beneficial. Alternatively, discharges with broader profiles, as in the VH mode or with high β poloidal, have shown improved performance. Non-inductive current drive is a means to access these modes of improved confinement on a steady state basis. Accordingly, experiments on non-inductive current drive are underway on the DIII-D tokamak using fast waves and electron cyclotron waves. Recent experiments on fast wave current drive have demonstrated the ability to drive up to 180kA of non-inductive current using 1.5MW of power at 60MHz, including the contribution from 1MW of ECCD and the bootstrap current. Higher power r.f. current drive systems are needed to affect strongly the current profile on DIII-D. An upgrade to the fast wave current drive system is underway to increase the total power to 6MW, using two additional antennas and two new 30-120MHz transmitters. Additionally, a 1MW prototype ECH system at 110GHz is being developed (with eventual upgrade to 10MW). With these systems, non-inductive current drive at the 1MA level will be available for experiments on profile control in DIII-D. ((orig.))

Towards fully non-inductive current drive operation in JET

International Nuclear Information System (INIS)

Litaudon, X.; Crisanti, F.; Alper, B.

2002-01-01

Quasi-steady operation has been achieved at JET in the high-confinement regime with internal transport barriers (ITBs). The ITB has been maintained up to 11 s. This duration, much larger than the energy confinement time, is already approaching a current resistive time. The high-performance phase is limited only by plant constraints. The radial profiles of the thermal electron and ion pressures have steep gradients typically at mid-plasma radius. A large fraction of non-inductive current (above 80%) is sustained throughout the high-performance phase with a poloidal beta exceeding unity. The safety factor profile plays an important role in sustaining the ITB characteristics. In this regime where the self-generated bootstrap current (up to 1.0 MA) represents 50% of the total current, the resistive evolution of the non-monotonic q-profile is slowed down by using off-axis lower-hybrid current drive. (author)

Towards fully non-inductive current drive operation in JET

International Nuclear Information System (INIS)

Litaudon, X.; Crisanti, F.; Alper, B.

2002-01-01

Quasi steady operation has been achieved at JET in the high confinement regime with Internal Transport Barriers, ITBs. The ITBs' performances are maintained up to 11 s. This duration, much larger than the energy confinement time, is already approaching a current resistive time. The high performance phase is limited only by plant constraints. The radial profiles of the thermal electron and ion pressures have steep gradients typically at mid-plasma radius. A large fraction of non-inductive current (above 80%) is sustained throughout the high performance phase with a poloidal beta exceeding unity. The safety factor profile plays an important role in sustaining the ITB characteristics. In this regime where the self-generated bootstrap current (up to LOMA) represents 50% of the total current, the resistive evolution of the non-monotonic q-profile is slowed down by using off-axis lower hybrid current drive. (authors)

Towards fully non-inductive current drive operation in JET

Energy Technology Data Exchange (ETDEWEB)

Litaudon, X. [Association Euratom-CEA Cadarache, Dept. de Recherches sur la Fusion Controlee, 13 - Saint-Paul-lez-Durance (France); Crisanti, F. [Association Euratom-ENEA sulla Fusione, Centro Ricerche Frascati (Italy); Alper, B. [Euratom-UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxon (United Kingdom)] [and others

2002-01-01

Quasi steady operation has been achieved at JET in the high confinement regime with Internal Transport Barriers, ITBs. The ITBs' performances are maintained up to 11 s. This duration, much larger than the energy confinement time, is already approaching a current resistive time. The high performance phase is limited only by plant constraints. The radial profiles of the thermal electron and ion pressures have steep gradients typically at mid-plasma radius. A large fraction of non-inductive current (above 80%) is sustained throughout the high performance phase with a poloidal beta exceeding unity. The safety factor profile plays an important role in sustaining the ITB characteristics. In this regime where the self-generated bootstrap current (up to LOMA) represents 50% of the total current, the resistive evolution of the non-monotonic q-profile is slowed down by using off-axis lower hybrid current drive. (authors)

Direct Coupling of Electron Beam Irradiation and Polymer Extrusion for a Continuous Polymer Modification in Molten State

International Nuclear Information System (INIS)

Stephan, M.

2006-01-01

The new approach of an e-beam initiating of chemical reactions in polymers in molten state results in some innovative results. High temperature, intensive macromolecular mobility and the absence of any crystallinity are some reasons for achieving unexpected structures, processing behaviour and properties changes in such treated thermoplastics and rubbers. Examples are a much more effective crosslinking of polyethylene and special rubbers, long chain branching of polypropylene or a partial crosslinking of polysulfone. Additionally, most of these modification effects are also achievable by a direct coupling of electron beam irradiation and conventional polymer extrusion processing for a continuous polymer modification in molten state. For realizing this unique processing technique a special MOBILE RADIATION FACILITY (MOBRAD1/T) was designed, constructed and manufactured in the IPF Dresden at which a lab-scale single screw extruder was adapted direct to an electron beam accelerator to realize a prompt irradiation of extruded polymer melt profiles before there solidification. Surprisingly, as a result of these short-time-melt reactions some effective and new polymer modification effects were found and will be presented

Beam profile monitors in the NLCTA

International Nuclear Information System (INIS)

Nantista, C.; Adolphsen, C.; Brown, R.L.; Fuller, R.; Rifkin, J.

1997-05-01

The transverse current profile in the Next Linear Collider Test Accelerator (NLCTA) electron beam can be monitored at several locations along the beam line by means of profile monitors. These consist of insertable phosphor screens, light collection and transport systems, CID cameras, a frame-grabber, and PC and VAX based image analysis software. In addition to their usefulness in tuning and steering the accelerator, the profile monitors are utilized for emittance measurement. A description of these systems and their performance is presented

Drug Release Profile from Calcium-Induced Alginate-Phosphate Composite Gel Beads

Directory of Open Access Journals (Sweden)

Yoshifumi Murata

2009-01-01

Full Text Available Calcium-induced alginate-phosphate composite gel beads were prepared, and model drug release profiles were investigated in vitro. The formation of calcium phosphate in the alginate gel matrix was observed and did not affect the rheological properties of the hydrogel beads. X-ray diffraction patterns showed that the calcium phosphate does not exist in crystalline form in the matrix. The initial release amount and release rate of a water-soluble drug, diclofenac, from the alginate gel beads could be controlled by modifying the composition of the matrix with calcium phosphate. In contrast, the release profile was not affected by the modification for hydrocortisone, a drug only slightly soluble in water.

Behavior Modification in the Classroom

Science.gov (United States)

Whitman, Mryon; Whitman, Joan

1971-01-01

This article presents the theoretical rationale for behavior modification, principally through its comparison with traditional psychotherapies, and suggests some behavior modification techniques for the classroom management of maladaptive behavior. (Author)

Single Amino Acid Modification of Adeno-Associated Virus Capsid Changes Transduction and Humoral Immune Profiles

Science.gov (United States)

Diprimio, Nina; Bowles, Dawn E.; Hirsch, Matthew L.; Monahan, Paul E.; Asokan, Aravind; Rabinowitz, Joseph; Agbandje-McKenna, Mavis

2012-01-01

Adeno-associated virus (AAV) vectors have the potential to promote long-term gene expression. Unfortunately, humoral immunity restricts patient treatment and in addition provides an obstacle to the potential option of vector readministration. In this study, we describe a comprehensive characterization of the neutralizing antibody (NAb) response to AAV type 1 (AAV1) through AAV5 both in vitro and in vivo. These results demonstrated that NAbs generated from one AAV type are unable to neutralize the transduction of other types. We extended this observation by demonstrating that a rationally engineered, muscle-tropic AAV2 mutant containing 5 amino acid substitutions from AAV1 displayed a NAb profile different from those of parental AAV2 and AAV1. Here we found that a single insertion of Thr from AAV1 into AAV2 capsid at residue 265 preserved high muscle transduction, while also changing the immune profile. To better understand the role of Thr insertion at position 265, we replaced all 20 amino acids and evaluated both muscle transduction and the NAb response. Of these variants, 8 mutants induced higher muscle transduction than AAV2. Additionally, three classes of capsid NAb immune profile were defined based on the ability to inhibit transduction from AAV2 or mutants. While no relationship was found between transduction, amino acid properties, and NAb titer or its cross-reactivity, these studies map a critical capsid motif involved in all steps of AAV infectivity. Our results suggest that AAV types can be utilized not only as templates to generate mutants with enhanced transduction efficiency but also as substrates for repeat administration. PMID:22593151

Cell Signalling Through Covalent Modification and Allostery

Science.gov (United States)

Johnson, Louise N.

Phosphorylation plays essential roles in nearly every aspect of cell life. Protein kinases catalyze the transfer of the γ-phosphate of ATP to a serine, threonine or tyrosine residue in protein substrates. This covalent modification allows activation or inhibition of enzyme activity, creates recognition sites for other proteins and promotes order/disorder or disorder/order transitions. These properties regulate ­signalling pathways and cellular processes that mediate metabolism, transcription, cell cycle progression, differentiation, cytoskeleton arrangement and cell movement, apoptosis, intercellular communication, and neuronal and immunological functions. In this lecture I shall review the structural consequences of protein phosphorylation using our work on glycogen phosphorylase and the cell cycle cyclin dependent protein kinases as illustrations. Regulation of protein phosphorylation may be disrupted in the diseased state and protein kinases have become high profile targets for drug development. To date there are 11 compounds that have been approved for clinical use in the treatment of cancer.

Chemoproteomics Reveals Chemical Diversity and Dynamics of 4-Oxo-2-nonenal Modifications in Cells.

Science.gov (United States)

Sun, Rui; Fu, Ling; Liu, Keke; Tian, Caiping; Yang, Yong; Tallman, Keri A; Porter, Ned A; Liebler, Daniel C; Yang, Jing

2017-10-01

4-Oxo-2-nonenal (ONE) derived from lipid peroxidation modifies nucleophiles and transduces redox signaling by its reactions with proteins. However, the molecular interactions between ONE and complex proteomes and their dynamics in situ remain largely unknown. Here we describe a quantitative chemoproteomic analysis of protein adduction by ONE in cells, in which the cellular target profile of ONE is mimicked by its alkynyl surrogate. The analyses reveal four types of ONE-derived modifications in cells, including ketoamide and Schiff-base adducts to lysine, Michael adducts to cysteine, and a novel pyrrole adduct to cysteine. ONE-derived adducts co-localize and exhibit crosstalk with many histone marks and redox sensitive sites. All four types of modifications derived from ONE can be reversed site-specifically in cells. Taken together, our study provides much-needed mechanistic insights into the cellular signaling and potential toxicities associated with this important lipid derived electrophile. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Current diffusion and flux consumption in Tore Supra

International Nuclear Information System (INIS)

Van Houtte, D.; Talvard, M.; Agostini, E.; Gil, C.; Hoang, G.T.; Lecoustey, P.; Parlange, F.; Rodriguez, L.; Vallet, J.C.

1991-01-01

TORE SUPRA has been designed to study long pulse plasmas (t > 30 s) at high plasma current (Ip < 2 MA) associated with high additional power (20 MW). Current diffusion studies are essentially based on the analysis of the plasma discharge paths. The current diffusion rate during the current rise phase is analysed with a numerical code using plasma resistivity profiles from Te profiles measured by the ECE diagnostic. Owing to the fact that the quantity of magnetic flux available in a tokamak is limited, perfect knowledge is required of the various components of the flux consumed in order to minimize consumption and to be able to define a suitable transformer size for future high current tokamak projects

Plasma surface modification of rigid contact lenses decreases bacterial adhesion.

Science.gov (United States)

Wang, Yingming; Qian, Xuefeng; Zhang, Xiaofeng; Xia, Wei; Zhong, Lei; Sun, Zhengtai; Xia, Jing

2013-11-01

Contact lens safety is an important topic in clinical studies. Corneal infections usually occur because of the use of bacteria-carrying contact lenses. The current study investigated the impact of plasma surface modification on bacterial adherence to rigid contact lenses made of fluorosilicone acrylate materials. Boston XO and XO2 contact lenses were modified using plasma technology (XO-P and XO2-P groups). Untreated lenses were used as controls. Plasma-treated and control lenses were incubated in solutions containing Staphylococcus aureus or Pseudomonas aeruginosa. MTT colorimetry, colony-forming unit counting method, and scanning electron microscopy were used to measure bacterial adhesion. MTT colorimetry measurements showed that the optical density (OD) values of XO-P and XO2-P were significantly lower than those of XO and XO2, respectively, after incubation with S. aureus (P lenses and to the XO2-P versus XO2 lenses incubated with S. aureus (P lenses incubated with P. aeruginosa (P lenses. Plasma surface modification can significantly decrease bacterial adhesion to fluorosilicone acrylate contact lenses. This study provides important evidence of a unique benefit of plasma technology in contact lens surface modification.

MODIFICATION OF PAPERMAKING GRADE FILLERS: A BRIEF REVIEW

Directory of Open Access Journals (Sweden)

Jing Shen

2009-08-01

Full Text Available The use of fillers in paper products can provide cost and energy savings, improved paper properties, increased productivities, and specifically desired paper functionalities. There are many problems associated with the use of fillers, such as unsuitability of calcium carbonate fillers in acid papermaking, negative effects of filler loading on paper strength, sizing, and retention, and tendencies of fillers to cause abrasion and dusting. In order to solve these problems and to make better use of fillers, many methods have been proposed, among which filler modification has been a hot topic. The available technologies of filler modification mainly include modification with inorganic substances, modification with natural polymers or their derivatives, modification with water-soluble synthetic polymers, modification with surfactants, modification with polymer latexes, hydrophobic modification, cationic modification, surface nano-structuring, physical modification by compressing, calcination or grinding, and modification for use in functional papers. The methods of filler modification can provide improved acid tolerant and optical properties of fillers, enhanced fiber-filler bonding, improved filler retention and filler sizabilities, alleviated filler abrasiveness, improved filler dispersability, and functionalization of filled papers. Filler modification has been an indispensable way to accelerate the development of high filler technology in papermaking, which is likely to create additional benefits to papermaking industry in the future.

Amplification of S-1 Spheromak current by an inductive current transformer

International Nuclear Information System (INIS)

Jardin, S.C.; Janos, A.; Yamada, M.

1985-11-01

We attempt to predict the consequences of adding an inductive current transformer (OH Transformer) to the present S-1 Spheromak experiment. Axisymmetric modeling with only classical dissipation shows an increase of toroidal current and a shrinking and hollowing of the current channel, conserving toroidal flux. These unstable profiles will undergo helical reconnection, conserving helicity K = ∫ A-vector x B-vector d tau while increasing the toroidal flux and decreasing the poloidal flux so that the plasma relaxes toward the Taylor state. This flux rearrangement is modeled by a new current viscosity term in the mean-field Ohm's law which conserves helicity and dissipates energy

In Situ Determination of Thermal Profiles during Czochralski Silicon Crystal Growth by an Eddy Current Technique.

Science.gov (United States)

Choe, Kwang Su.

An eddy current testing method was developed to continuously monitor crystal growth process and determine thermal profiles in situ during Czochralski silicon crystal growth. The work was motivated by the need to improve the quality of the crystal by controlling thermal gradients and annealing history over the growth cycle. The experimental concept is to monitor intrinsic electrical conductivities of the growing crystal and deduce temperature values from them. The experiments were performed in a resistance-heated Czochralski puller with a 203 mm (8 inch) diameter crucible containing 6.5 kg melt. The silicon crystals being grown were about 80 mm in diameter and monitored by an encircling sensor operating at three different test frequencies (86, 53 and 19 kHz). A one-dimensional analytical solution was employed to translate the detected signals into electrical conductivities. In terms of experiments, the effects of changes in growth condition, which is defined by crystal and crucible rotation rates, crucible position, pull rate, and hot-zone configuration, were investigated. Under a given steady-state condition, the thermal profile was usually stable over the entire length of crystal growth. The profile shifted significantly, however, when the crucible rotation rate was kept too high. As a direct evidence to the effects of melt flow on heat transfer process, a thermal gradient minimum was observed about the crystal/crucible rotation combination of 20/-10 rpm cw. The thermal gradient reduction was still most pronounced when the pull rate or the radiant heat loss to the environment was decreased: a nearly flat axial thermal gradient was achieved when either the pull rate was halved or the height of the exposed crucible wall was effectively doubled. Under these conditions, the average axial thermal gradient along the surface of the crystal was about 4-5 ^{rm o}C/mm. Regardless of growth condition, the three-frequency data revealed radial thermal gradients much larger

CAR models: next-generation CAR modifications for enhanced T-cell function

Directory of Open Access Journals (Sweden)

Daniel Abate-Daga

2016-01-01

Full Text Available T cells genetically targeted with a chimeric antigen receptor (CAR to B-cell malignancies have demonstrated tremendous clinical outcomes. With the proof in principle for CAR T cells as a therapy for B-cell malignancies being established, current and future research is being focused on adapting CAR technology to other cancers, as well as enhancing its efficacy and/or safety. The modular nature of the CAR, extracellular antigen-binding domain fused to a transmembrane domain and intracellular T-cell signaling domains, allows for optimization by replacement of the various components. These modifications are creating a whole new class of therapeutic CARs. In this review, we discuss the recent major advances in CAR design and how these modifications will impact its clinical application.

Monte Carlo simulation of lower hybrid current drive in tokamaks

International Nuclear Information System (INIS)

Sipilae, S.K.; Heikkinen, J.A.

1994-01-01

In the report a method for noninductive current drive studies based on three-dimensional simulation of test particle orbits is presented. A Monte Carlo momentum diffusion operator is developed to model the wave-particle interaction. The scheme can be utilised in studies of current drive efficiency as well as in examining the current density profiles caused by waves with a finite parallel wave number spectrum and a nonuniform power deposition profile in a toroidal configuration space of arbitrary shape. Calculations performed with a uniform poorer deposition profile of lower hybrid waves for axisymmetric magnetic configurations having different aspect ratios and poloidal cross-section shape confirm the semianalytic estimates for the current drive efficiency based on the solutions of the flux surface averaged Fokker-Planck equation for configurations with circular poloidal cross section. The consequences of the combined effect of radial diffusion, magnetic trapping and radially nonhomogeneous power deposition and background plasma parameter profiles are investigated

Modifications to Replacement Costs System

International Nuclear Information System (INIS)

Godec, M.

1989-01-01

The purpose of this memorandum is to document the improvements and modifications made to the Replacement Costs of Crude Oil (REPCO) Supply Analysis System. While some of this work was performed under our previous support contract to DOE/ASFE, we are presenting all modifications and improvements are presented here for completeness. The memo primarily documents revisions made to the Lower-48 Onshore Model. Revisions and modifications made to other components and models in the REPCO system which are documented elsewhere are only highlighted in this memo. Generally, the modifications made to the Lower-48 Onshore Model reflect changes that have occurred in domestic drilling, oil field costs, and reserves since 1982, the date of the most recent available data used for the original Replacement Costs report, published in 1985

Surface modification of materials by ion implantations for industrial and medical applications. Final report of a co-ordinated research project

International Nuclear Information System (INIS)

2000-07-01

The objectives of the Co-ordinated Research Project on Modification of Materials by Ion Treatment for Industrial Applications were to develop economically acceptable surface modification techniques leading to thick treated layers, to predict ion beam mixing and impurity atom migration during and after implantation, and to evaluate the tribological post-implantation properties and performance of treated components. This TECDOC summarises the current status and prospects in surface modification by ion implantation methodology and technology, providing new information in basic and applied research

Surface modification of materials by ion implantations for industrial and medical applications. Final report of a co-ordinated research project

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-07-01

The objectives of the Co-ordinated Research Project on Modification of Materials by Ion Treatment for Industrial Applications were to develop economically acceptable surface modification techniques leading to thick treated layers, to predict ion beam mixing and impurity atom migration during and after implantation, and to evaluate the tribological post-implantation properties and performance of treated components. This TECDOC summarises the current status and prospects in surface modification by ion implantation methodology and technology, providing new information in basic and applied research.

Chemical Modification of Boron-Doped Diamond Electrodes for Applications to Biosensors and Biosensing.

Science.gov (United States)

Svítková, Jana; Ignat, Teodora; Švorc, Ľubomír; Labuda, Ján; Barek, Jiří

2016-05-03

Boron-doped diamond (BDD) is a prospective electrode material that possesses many exceptional properties including wide potential window, low noise, low and stable background current, chemical and mechanical stability, good biocompatibility, and last but not least exceptional resistance to passivation. These characteristics extend its usability in various areas of electrochemistry as evidenced by increasing number of published articles over the past two decades. The idea of chemically modifying BDD electrodes with molecular species attached to the surface for the purpose of creating a rational design has found promising applications in the past few years. BDD electrodes have appeared to be excellent substrate materials for various chemical modifications and subsequent application to biosensors and biosensing. Hence, this article presents modification strategies that have extended applications of BDD electrodes in electroanalytical chemistry. Different methods and steps of surface modification of this electrode material for biosensing and construction of biosensors are discussed.

Comparison of Cluster Lensing Profiles with Lambda CDM Predictions

Energy Technology Data Exchange (ETDEWEB)

Broadhurst, Tom; /Tel Aviv U.; Umetsu, Keiichi; /Taipei, Inst. Astron. Astrophys.; Medezinski, Elinor; /Tel Aviv U.; Oguri, Masamune; /KIPAC, Menlo Park; Rephaeli, Yoel; /Tel Aviv U. /San Diego, CASS

2008-05-21

We derive lens distortion and magnification profiles of four well known clusters observed with Subaru. Each cluster is very well fitted by the general form predicted for Cold Dark Matter (CDM) dominated halos, with good consistency found between the independent distortion and magnification measurements. The inferred level of mass concentration is surprisingly high, 8 < c{sub vir} < 15 ( = 10.39 {+-} 0.91), compared to the relatively shallow profiles predicted by the {Lambda}CDM model, c{sub vir} = 5.06 {+-} 1.10 (for = 1.25 x 10{sup 15} M{sub {circle_dot}}/h). This represents a 4{sigma} discrepancy, and includes the relatively modest effects of projection bias and profile evolution derived from N-body simulations, which oppose each other with little residual effect. In the context of CDM based cosmologies, this discrepancy implies some modification of the widely assumed spectrum of initial density perturbations, so clusters collapse earlier (z {ge} 1) than predicted (z < 0.5) when the Universe was correspondingly denser.

Influence of tungsten microstructure and ion flux on deuterium plasma-induced surface modifications and deuterium retention

Energy Technology Data Exchange (ETDEWEB)

Buzi, Luxherta [IEK - Plasmaphysik, Forschungszentrum Juelich GmbH, Association EURATOM-FZJ, Juelich (Germany); FOM Institute DIFFER-Dutch Institute for Fundamental Energy Research (Netherlands); Ghent University (Belgium); Temmerman, Greg de [FOM Institute DIFFER-Dutch Institute for Fundamental Energy Research (Netherlands); Reinhart, Michael; Matveev, Dmitry; Unterberg, Bernhard; Wienhold, Peter; Breuer, Uwe; Kreter, Arkadi [IEK - Plasmaphysik, Forschungszentrum Juelich GmbH, Association EURATOM-FZJ, Juelich (Germany); Oost, Guido van [Ghent University (Belgium)

2014-07-01

Tungsten is to be used as plasma-facing material for the ITER divertor due to its favourable thermal properties, low erosion and fuel retention. Bombardment of tungsten by low energy ions of hydrogen isotopes, at different surface temperature, can lead to surface modifications and influence the fuel accumulation in the material. This contribution will assess the impact of material microstructure and the correlation between the particle flux, surface modifications and deuterium retention in tungsten. Tungsten samples were exposed to deuterium plasma at a surface temperature of 510 K, 670 K and 870 K, ion energy of 40 eV and ion fluence of 10{sup 26} m{sup -2}. The high and low ion flux ranges were in the order 10{sup 24} m{sup -2}s{sup -1} and 10{sup 22} m{sup -2}s{sup -1}. Depth profiling of deuterium in all the samples was done by secondary ion mass spectroscopy technique and a scanning electron microscope was used to investigate the surface modifications. Modelling of the D desorption spectra with the coupled reaction diffusion system model will be also presented.

On transport and the bootstrap current in toroidal plasmas

International Nuclear Information System (INIS)

Connor, J.W.; Taylor, J.B.

1987-01-01

The recently reported observation of the bootstrap current in a tokamak plasma highlights the problem of reconciling this neoclassical effect with the anomalous (i.e., non-neoclassical) electron thermal transport. This Comment reviews the bootstrap current and considers the implications of a self-consistent modification of neoclassical theory based on an enhanced electron-electron interaction. (author)

Value-impact assessment of safety-related modifications

International Nuclear Information System (INIS)

Knowles, W.M.C.; Dinnie, K.S.; Gordon, C.W.

1992-01-01

Like other nuclear utilities, Ontario Hydro, as part of its risk management activities, continually assesses the safety of its nuclear operations. In addition, new regulatory requirements are being applied to the older nuclear power plants. Both of these result in proposed plant modifications designed to reduce the risk to the public. However, modifications to an operating plant can have serious economic effects, and the resources, both financial and personnel, required for the implementation of these modifications are limited. Thus, all potential benefits and effects of a proposed modification must be thoroughly investigated to judge whether the modification is beneficial. Ontario Hydro has begun to use comprehensive value-impact assessments, utilizing plant-specific probabilistic risk assessments (PRAs), as tools to provide an informed basis for judgments on the benefit of safety-related modifications. The results from value-impact assessments can also be used to prioritize the implementation of these modifications

Beam profile for Malaysian electron accelerator

International Nuclear Information System (INIS)

Abu Bakar Ghazali; Muhamad Zahidee Taat

2007-01-01

This paper comprises of two calculations that require in designing a dose profile for an electron accelerator machine before its fabrication. The first is to calculate the beam deflection due to changes of high voltage (HV) supply as well as the deflection coil currents so that the electron beam will only scan at the window foil of 18 cm length and 6 cm width. Secondly, we also require to calculate the beam profile at 50 mm underneath the window foil. The electron gun that produces a beam of 10 mm diameter has to be oscillated in a sawtooth wave for the prescribed window size at frequencies of 50 Hz and 400 Hz along the length and width directions respectively. For the beam deflection, we apply a basic formula from Lorentz force law to obtain a set of HV supply and the coil current that is suitable for both deflections and this result can assist in designing the coil current against HV changes via an electronic controller. The dose profile was calculated using the RMS current formulation along the length direction. We found that the measured and the calculated RMS currents are in comparable for the case of 1 MeV, 50 mA accelerator facility that is going to be installed at Nuclear Malaysia complex. A similar measurement will be carried out for our locally designed accelerator of 150 KeV, 10 mA after fabrication and installation of the machine are completed. (Author)

Attention bias for chocolate increases chocolate consumption--an attention bias modification study.

Science.gov (United States)

Werthmann, Jessica; Field, Matt; Roefs, Anne; Nederkoorn, Chantal; Jansen, Anita

2014-03-01

The current study examined experimentally whether a manipulated attention bias for food cues increases craving, chocolate intake and motivation to search for hidden chocolates. To test the effect of attention for food on subsequent chocolate intake, attention for chocolate was experimentally modified by instructing participants to look at chocolate stimuli ("attend chocolate" group) or at non-food stimuli ("attend shoes" group) during a novel attention bias modification task (antisaccade task). Chocolate consumption, changes in craving and search time for hidden chocolates were assessed. Eye-movement recordings were used to monitor the accuracy during the experimental attention modification task as possible moderator of effects. Regression analyses were conducted to test the effect of attention modification and modification accuracy on chocolate intake, craving and motivation to search for hidden chocolates. Results showed that participants with higher accuracy (+1 SD), ate more chocolate when they had to attend to chocolate and ate less chocolate when they had to attend to non-food stimuli. In contrast, for participants with lower accuracy (-1 SD), the results were exactly reversed. No effects of the experimental attention modification on craving or search time for hidden chocolates were found. We used chocolate as food stimuli so it remains unclear how our findings generalize to other types of food. These findings demonstrate further evidence for a link between attention for food and food intake, and provide an indication about the direction of this relationship. Copyright © 2013 Elsevier Ltd. All rights reserved.

Analysis and solution of current spike occurred in dynamic compensation of self-powered neutron detectors

International Nuclear Information System (INIS)

Peng, Xingjie; Li, Qing; Wang, Kan

2017-01-01

Highlights: • The current spike problem is observed in the dynamic compensation process of SPNDs. • The current spike is caused by unphysical current change due to range switching. • Modification on the compensation algorithm is introduced to deal with current spike. - Abstract: Dynamic compensation methods are required to improve the response speed of the Self-Powered Neutron Detectors (SPNDs) and make it possible to apply the SPNDs for core monitoring and surveillance. During the experimental test of the compensation method based on linear matrix inequality (LMI), spikes are observed in the compensated SPND current. After analyzing the measurement data, the cause is fixed on the unphysical change of the uncompensated SPND current due to range switching. Then some modifications on the dynamic compensation algorithms are proposed to solve the current spike problem.

Real-time control of the plasma density profile on ASDEX upgrade

International Nuclear Information System (INIS)

Mlynek, Alexander

2010-01-01

The tokamak concept currently is the most promising approach to future power generation by controlled thermonuclear fusion. The spatial distribution of the particle density in the toroidally confined fusion plasma is of particular importance. This thesis work therefore focuses on the question as to what extent the shape of the density profile can be actively controlled by a feedback loop in the fusion experiment ASDEX Upgrade. There are basically two essential requirements for such feedback control of the density profile, which has been experimentally demonstrated within the scope of this thesis work: On the one hand, for this purpose the density profile must be continuously calculated under real-time constraints during a plasma discharge. The calculation of the density profile is based on the measurements of a sub-millimeter interferometer, which provides the line-integrated electron density along 5 chords through the plasma. Interferometric density measurements can suffer from counting errors by integer multiples of 2π when detecting the phase difference between a probing and a reference beam. As such measurement errors have severe impact on the reconstructed density profile, one major part of this work consists in the development of new readout electronics for the interferometer, which allows for detection of such measurement errors in real-time with high reliability. A further part of this work is the design of a computer algorithm which reconstructs the spatial distribution of the plasma density from the line-integrated measurements. This algorithm has to be implemented on a computer which communicates the measured data to other computers in real-time, especially to the tokamak control system. On the other hand, a second fundamental requirement for the successful implementation of a feedback controller is the identification of at least one actuator which enables a modification of the density profile. Here, electron cyclotron resonance heating (ECRH) has been

Evaluation of the methodologies used to generate random pavement profiles based on the power spectral density: An approach based on the International Roughness Index

Directory of Open Access Journals (Sweden)

Boris Jesús Goenaga

2017-01-01

Full Text Available The pavement roughness is the main variable that produces the vertical excitation in vehicles. Pavement profiles are the main determinant of (i discomfort perception on users and (ii dynamic loads generated at the tire-pavement interface, hence its evaluation constitutes an essential step on a Pavement Management System. The present document evaluates two specific techniques used to simulate pavement profiles; these are the shaping filter and the sinusoidal approach, both based on the Power Spectral Density. Pavement roughness was evaluated using the International Roughness Index (IRI, which represents the most used index to characterize longitudinal road profiles. Appropriate parameters were defined in the simulation process to obtain pavement profiles with specific ranges of IRI values using both simulation techniques. The results suggest that using a sinusoidal approach one can generate random profiles with IRI values that are representative of different road types, therefore, one could generate a profile for a paved or an unpaved road, representing all the proposed categories defined by ISO 8608 standard. On the other hand, to obtain similar results using the shaping filter approximation a modification in the simulation parameters is necessary. The new proposed values allow one to generate pavement profiles with high levels of roughness, covering a wider range of surface types. Finally, the results of the current investigation could be used to further improve our understanding on the effect of pavement roughness on tire pavement interaction. The evaluated methodologies could be used to generate random profiles with specific levels of roughness to assess its effect on dynamic loads generated at the tire-pavement interface and user’s perception of road condition.