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Sample records for high-performance nbi plasmas

  1. Conceptual design of NBI beamline for VEST plasma heating

    Energy Technology Data Exchange (ETDEWEB)

    Kim, T.S., E-mail: tskim@kaeri.re.kr; In, S.R.; Jeong, S.H.; Park, M.; Chang, D.H.; Jung, B.K.; Lee, K.W.

    2016-11-01

    Highlights: • VEST NBI injector is conceptually designed to support further VEST plasma experiment. • VEST NBI injector composed of 2 sets of 20 keV/25A magnetic cusp type bucket ion source, neutralizer ducts, electrostatic ion dumps, NB vessel with cryopump, and rotating calorimerter. • The vacuum vessel of the beamline is divided into two parts for high injection efficiency and different direction (co- and counter-current) of neutral beam injection. • An ion source for the VEST NBI system was also designed to deliver neutral hydrogen beams with a power of 0.3 MW. The plasma generator of the VEST NB ion source has modified TFTR bucket multi-cusp chamber. The plasma generator has twelve hair-pin shaped tungsten filaments used as a cathode and an arc chamber including a bucket and an electron dump which serve as anode. The accelerator system consists of three grids, each having extraction area of 100 mm × 320 mm and 64 shaped slits of 3 mm spacing. • The preliminary structure design and the layout of the main components of the injector have been completed. Simulation and calculation for optimization of the NB beamline design results prove that the parameters of ion source, neutralization efficiency (76%:95% equilibrium neutralization efficiency), and beam power transmission efficiency (higher than 90%) are in agreement with design targets of the VEST NB beamline. • This VEST NBI system will provide a neutral beam of ∼0.6 MW for both heating and current drive in torus plasma. - Abstract: A 10 m s-pulsed NBI (Neutral Beam Injection) system for VEST (Versatile Experiment Spherical Torus) plasma heating is designed to provide a beam power of more than 0.6 MW with 20 keV H° neutrals. The VEST NBI injector is composed of 2 sets of 20 keV/25A magnetic cusp type bucket ion source, neutralizer ducts, residual ion dump, NB vessel with a cryopump, and rotating calorimeter. The position and size of these beamline components are roughly determined with geometric

  2. NBI - plasma vaporization hybrid approach in bladder cancer endoscopic management.

    Science.gov (United States)

    Stănescu, F; Geavlete, B; Georgescu, D; Jecu, M; Moldoveanu, C; Adou, L; Bulai, C; Ene, C; Geavlete, P

    2014-06-15

    A prospective study was performed aiming to evaluate the surgical efficacy, perioperative safety profile, diagnostic accuracy and medium term results of a multi-modal approach consisting in narrow band imaging (NBI) cystoscopy and bipolar plasma vaporization (BPV) when compared to the standard protocol represented by white light cystoscopy (WLC) and transurethral resection of bladder tumors (TURBT). A total of 260 patients with apparently at least one bladder tumor over 3 cm were included in the trial. In the first group, 130 patients underwent conventional and NBI cystoscopy followed by BPV, while in a similar number of cases of the second arm, classical WLC and TURBT were applied. In all non-muscle invasive bladder tumors' (NMIBT) pathologically confirmed cases, standard monopolar Re-TUR was performed at 4-6 weeks after the initial intervention, followed by one year' BCG immunotherapy. The follow-up protocol included abdominal ultrasound, urinary cytology and WLC, performed every 3 months for a period of 2 years. The obturator nerve stimulation, bladder wall perforation, mean hemoglobin level drop, postoperative bleeding, catheterization period and hospital stay were significantly reduced for the plasma vaporization technique by comparison to conventional resection. Concerning tumoral detection, the present data confirmed the NBI superiority when compared to standard WLC regardless of tumor stage (95.3% vs. 65.1% for CIS, 93.3% vs. 82.2% for pTa, 97.4% vs. 94% for pT1, 95% vs. 84.2% overall). During standard Re-TUR the overall (6.3% versus 17.4%) and primary site (3.6% versus 12.8%) residual tumors' rates were significantly lower for the NBI-BPV group. The 1 (7.2% versus 18.3%) and 2 (11.5% versus 25.8%) years' recurrence rates were substantially lower for the combined approach. NBI cystoscopy significantly improved diagnostic accuracy, while bipolar technology showed a higher surgical efficiency, lower morbidity and faster postoperative recovery. The combined

  3. Recent results with NBI plasmas in TJ-II stellarator

    Energy Technology Data Exchange (ETDEWEB)

    Liniers, M.; Ascasibar, E.; Estrada, T.; Tabares, F. L.; Acedo, M.; Alonso, J.; Balbin, R.; Blanco, B.; Branas, B.; Cappa, A.; Carrasco, R.; Castejon, F.; Fernandez, A.; Fontdecaba, J. M.; Fuentes, C.; Garcia, A.; Garcia-Cortes, I.; Guasp, J.; Hidalgo, A.; Hidalgo, C.; Jimenez, R.; Lopez-Bruna, D.; Lopez-Fraguas, A.; Marcon, G.; McCarthy, K. J.; Medina, F.; Medrano, M.; Ochando, M.; Pastor, I.; Pedrosa, M. A.; Rapisarda, D.; Sanchez, E.; Sanchez, M.; Sanchez, J.; Tafalla, D.; Wolfers, G.; Zurro, B.

    2005-07-01

    During the last experimental campaign Neutral Beam Injection into TJ-II plasmas has been available, with a single H0 beam aiming tangentially in the Co-direction. As the ion source conditioning was improved along the campaign, the injected power increased from 200 kW to 400 kW port-through, and the beam energy was raised from 26 kV to 30 kV [1]. Target plasmas are created by ECR heating, using two gyrotrons of 200 kW power, at the second harmonic frequency (53 GHz). The injection direction of the microwaves can be steered by means of movable mirrors placed inside the vacuum chamber, making it possible to vary the power deposition region from the plasma core (on-axis) to the outer regions near ?=0.5 (off-axis). The plasma temperature and density profiles obtained with on-axis or off axis ECRH are seen to differ widely, allowing us to study the neutral beam absorption in two qualitatively different plasma target scenarios. Other factors affecting the plasma profiles have also been investigated, such as the magnetic configuration or the OH-driven current. TJ-II has the capability of varying the magnetic configuration by changing the ratio of the current through the circular and helical conductors that form the Central Conductor. The iota values can be swept between 0.9 and 2.2 and the magnetic well between -1% and 6% giving rise to configurations with different confinement properties. A negative OH driven current has the effect of increasing the magnetic shear value, allowing low-order rationals in the central region which have been seen to modify density profiles in ECH plasmas. In most NBI discharges the central plasma density increases continuously from ECH typical values below 1.1 x 10 19 m-3 up to 6.5 x 10 19 m-3, as the beam is injected, until a thermal collapse that terminates the discharge is reached. So far, density control with NBI plasmas has not been achieved, although an improved behaviour is observed with wall cleaning. (Author)

  4. Transport studies in high-performance field reversed configuration plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, S., E-mail: sgupta@trialphaenergy.com; Barnes, D. C.; Dettrick, S. A.; Trask, E.; Tuszewski, M.; Deng, B. H.; Gota, H.; Gupta, D.; Hubbard, K.; Korepanov, S.; Thompson, M. C.; Zhai, K.; Tajima, T. [Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688 (United States)

    2016-05-15

    A significant improvement of field reversed configuration (FRC) lifetime and plasma confinement times in the C-2 plasma, called High Performance FRC regime, has been observed with neutral beam injection (NBI), improved edge stability, and better wall conditioning [Binderbauer et al., Phys. Plasmas 22, 056110 (2015)]. A Quasi-1D (Q1D) fluid transport code has been developed and employed to carry out transport analysis of such C-2 plasma conditions. The Q1D code is coupled to a Monte-Carlo code to incorporate the effect of fast ions, due to NBI, on the background FRC plasma. Numerically, the Q1D transport behavior with enhanced transport coefficients (but with otherwise classical parametric dependencies) such as 5 times classical resistive diffusion, classical thermal ion conductivity, 20 times classical electron thermal conductivity, and classical fast ion behavior fit with the experimentally measured time evolution of the excluded flux radius, line-integrated density, and electron/ion temperature. The numerical study shows near sustainment of poloidal flux for nearly 1 ms in the presence of NBI.

  5. Modelling of combined ICRF and NBI heating in JET hybrid plasmas

    Directory of Open Access Journals (Sweden)

    Gallart Dani

    2017-01-01

    Full Text Available During the 2015-2016 JET campaigns many efforts have been devoted to the exploration of high performance plasma scenarios envisaged for ITER operation. In this paper we model the combined ICRF+NBI heating in selected key hybrid discharges using PION. The antenna frequency was tuned to match the cyclotron frequency of minority hydrogen (H at the center of the tokamak coinciding with the second harmonic cyclotron resonance of deuterium. The modelling takes into account the synergy between ICRF and NBI heating through the second harmonic cyclotron resonance of deuterium beam ions which allows us to assess its impact on the neutron rate RNT. We evaluate the influence of H concentration which was varied in different discharges in order to test their role in the heating performance. According to our modelling, the ICRF enhancement of RNT increases by decreasing the H concentration which increases the ICRF power absorbed by deuterons. We find that in the recent hybrid discharges this ICRF enhancement was in the range of 10-25%. Finally, we extrapolate the results to D-T and find that the best performing hybrid discharges correspond to an equivalent fusion power of ∼7.0 MW in D-T.

  6. Development of Powerful RF Plasma Sources for Present and Future NBI Systems

    Science.gov (United States)

    Speth, E.; NBI-Team

    2004-02-01

    This paper deals with the topic of RF plasma sources and their application in high-power neutral beam heating systems for nuclear fusion devices. RF sources represent an interesting alternative to the conventional arc discharge sources. Due to the absence of hot filaments they exhibit an inherent simplicity both in mechanical and electrical aspects and consequently offer advantages in terms of cost savings, gain in availability and reliability and reduced maintenance. This renders the RF plasma source attractive for any long pulse (> 10 sec) NBI system and in particular for the ITER NBI system. The latter, however, requires that the RF plasma source is also capable of delivering negative rather than positive hydrogen ions. In the first part of the paper the types, characteristics and operation experience of RF plasma sources for positive ions in operation are described. The second part is devoted to the development for ITER NBI: The basic requirements, physics and technology issues and the present status are discussed.

  7. Long Pulse High Performance Plasma Scenario Development for the National Spherical Torus Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Kessel, C.E.; Bell, R.E.; Bell, M.G.; Gates, D.A.; Harvey, R.W.

    2006-01-01

    The National Spherical Torus Experiment [Ono et al., Nucl. Fusion, 44, 452 (2004)] is targeting long pulse high performance, noninductive sustained operations at low aspect ratio, and the demonstration of nonsolenoidal startup and current rampup. The modeling of these plasmas provides a framework for experimental planning and identifies the tools to access these regimes. Simulations based on neutral beam injection (NBI)-heated plasmas are made to understand the impact of various modifications and identify the requirements for (1) high elongation and triangularity, (2) density control to optimize the current drive, (3) plasma rotation and/or feedback stabilization to operate above the no-wall limit, and (4) electron Bernstein waves (EBW) for off-axis heating/current drive (H/CD). Integrated scenarios are constructed to provide the transport evolution and H/CD source modeling, supported by rf and stability analyses. Important factors include the energy confinement, Zeff, early heating/H mode, broadening of the NBI-driven current profile, and maintaining q(0) and qmin>1.0. Simulations show that noninductive sustained plasmas can be reached at IP=800 kA, BT=0.5 T, 2.5, N5, 15%, fNI=92%, and q(0)>1.0 with NBI H/CD, density control, and similar global energy confinement to experiments. The noninductive sustained high plasmas can be reached at IP=1.0 MA, BT=0.35 T, 2.5, N9, 43%, fNI=100%, and q(0)>1.5 with NBI H/CD and 3.0 MW of EBW H/CD, density control, and 25% higher global energy confinement than experiments. A scenario for nonsolenoidal plasma current rampup is developed using high harmonic fast wave H/CD in the early low IP and low Te phase, followed by NBI H/CD to continue the current ramp, reaching a maximum of 480 kA after 3.4 s.

  8. Exit points, on plasma, of lost fast ions during NBI in TJ-II; Puntos de salida en el plasma de los iones rapidos durante NBI en el TJ-II

    Energy Technology Data Exchange (ETDEWEB)

    Guasp, J.

    1995-07-01

    The distribution of the exit points, on plasma border, for the lost fast ions during tangential balanced NBI in TJ-II helical axis Stellarator is theoretically analysed, as well for direct as for delayed losses. The link between, the position of those exit points and the corresponding at birth, orbits and drifts is analysed also. It is shown that such relation is rather independent of beam energy and plasma density and is mainly related to the magnetic configuration characteristics. This study is a needed intermediate step to the analysis of impacts of those ions on the vacuum vessel of TJ-II. (Author) 2 refs.

  9. Plasma grid design for optimized filter field configuration for the NBI test facility ELISE

    Energy Technology Data Exchange (ETDEWEB)

    Nocentini, R. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, D-85740 Garching (Germany)], E-mail: riccardo.nocentini@ipp.mpg.de; Gutser, R.; Heinemann, B.; Froeschle, M.; Riedl, R. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, D-85740 Garching (Germany)

    2009-12-15

    Maintenance-free RF sources for negative hydrogen ions with moderate extraction areas (100-200 cm{sup 2}) have been successfully developed in the last years at IPP Garching in the test facilities BATMAN and MANITU. A facility with larger extraction area (1000 cm{sup 2}), ELISE, is being designed with a 'half-size' ITER-like extraction system, pulsed ion acceleration up to 60 kV for 10 s and plasma generation up to 1 h. Due to the large size of the source, the magnetic filter field (FF) cannot be produced solely by permanent magnets. Therefore, an additional magnetic field produced by current flowing through the plasma grid (PG current) is required. The filter field homogeneity and the interaction with the electron suppression magnetic field have been studied in detail by finite element method (FEM) during the ELISE design phase. Significant improvements regarding the field homogeneity have been introduced compared to the ITER reference design. Also, for the same PG current a 50% higher field in front of the grid has been achieved by optimizing the plasma grid geometry. Hollow spaces have been introduced in the plasma grid for a more homogeneous PG current distribution. The introduction of hollow spaces also allows the insertion of permanent magnets in the plasma grid.

  10. Application of beam emission spectroscopy to NBI plasmas of Heliotron J.

    Science.gov (United States)

    Kobayashi, S; Kado, S; Oishi, T; Kagawa, T; Ohshima, S; Mizuuchi, T; Nagasaki, K; Yamamoto, S; Okada, H; Minami, T; Murakami, S; Lee, H Y; Minami, T; Nakamura, Y; Hanatani, K; Konoshima, S; Takeuchi, M; Toushi, K; Sano, F

    2010-10-01

    This paper describes the application of the beam emission spectroscopy (BES) to Heliotron J, having the nonsymmetrical helical-magnetic-axis configuration. The spectral and spatial profile of the beam emission has been estimated by the numerical calculation taking the collisional excitation processes between plasmas (electrons/ions) and beam atoms. Two sets of the sightlines with good spatial resolution are presented. One is the optimized viewing chords which have 20 sightlines and observe the whole plasma region with the spatial resolution Δρ less than ±0.055 using the newly designed viewing port. The other is 15 sightlines from the present viewing port of Heliotron J for the preliminary measurement to discuss the feasibility of the density fluctuation measurement by BES. The beam emission has been measured by a monochromator with a CCD camera. A good consistency has been obtained between the spectral profiles of the beam emission measured by the monochromator and the beam emission spectrum deduced by the model calculation. An avalanche photodiode with an interference filter system was also used to evaluate the signal-to-noise (S/N) ratio of the beam emission in the present experimental setup. The modification of the optical system is being planned to improve the S/N ratio, which will enable us to estimate the density fluctuation in Heliotron J.

  11. High-performance simulations for atmospheric pressure plasma reactor

    Science.gov (United States)

    Chugunov, Svyatoslav

    Plasma-assisted processing and deposition of materials is an important component of modern industrial applications, with plasma reactors sharing 30% to 40% of manufacturing steps in microelectronics production. Development of new flexible electronics increases demands for efficient high-throughput deposition methods and roll-to-roll processing of materials. The current work represents an attempt of practical design and numerical modeling of a plasma enhanced chemical vapor deposition system. The system utilizes plasma at standard pressure and temperature to activate a chemical precursor for protective coatings. A specially designed linear plasma head, that consists of two parallel plates with electrodes placed in the parallel arrangement, is used to resolve clogging issues of currently available commercial plasma heads, as well as to increase the flow-rate of the processed chemicals and to enhance the uniformity of the deposition. A test system is build and discussed in this work. In order to improve operating conditions of the setup and quality of the deposited material, we perform numerical modeling of the plasma system. The theoretical and numerical models presented in this work comprehensively describe plasma generation, recombination, and advection in a channel of arbitrary geometry. Number density of plasma species, their energy content, electric field, and rate parameters are accurately calculated and analyzed in this work. Some interesting engineering outcomes are discussed with a connection to the proposed setup. The numerical model is implemented with the help of high-performance parallel technique and evaluated at a cluster for parallel calculations. A typical performance increase, calculation speed-up, parallel fraction of the code and overall efficiency of the parallel implementation are discussed in details.

  12. NBI and NBI Combined with Magnifying Colonoscopy

    Directory of Open Access Journals (Sweden)

    Mineo Iwatate

    2012-01-01

    Full Text Available Although magnifying chromoendoscopy had been a reliable diagnostic tool, narrow-band imaging (NBI has been developed in Japan since 1999 and has now replaced the major role of chromoendoscopy because of its convenience and simplicity. In this paper, we principally describe the efficacy of magnifying chromoendoscopy and magnifying colonoscopy with NBI for detection, histological prediction, estimation of the depth of early colorectal cancer, and future prospects. Although some meta-analyses have concluded that NBI is not superior to white light imaging for detection of adenomatous polyps in screening colonoscopy, NBI with magnification colonoscopy is useful for histological prediction, or for estimating the depth of invasion. To standardize these diagnostic strategies, we will focus on the NBI International Colorectal Endoscopic (NICE classification proposed for use by endoscopists with or without a magnifying endoscope. However, more prospective research is needed to prove that this classification can be applied with satisfactory availability, feasibility, and reliability. In the future, NBI might contribute to the evaluation of real-time histological prediction during colonoscopy, which has substantial benefits for both reducing the risk of polypectomy and saving the cost of histological evaluation by resecting and discarding diminutive adenomatous polyps (resect and discard strategy.

  13. Experimental observation of multi-scale interactions among kink /tearing modes and high-frequency fluctuations in the HL-2A core NBI plasmas

    Science.gov (United States)

    Chen, W.; Jiang, M.; Xu, Y.; Shi, P. W.; Yu, L. M.; Ding, X. T.; Shi, Z. B.; Ji, X. Q.; Yu, D. L.; Li, Y. G.; Yang, Z. C.; Zhong, W. L.; Qiu, Z. Y.; Li, J. Q.; Dong, J. Q.; Yang, Q. W.; Liu, Yi.; Yan, L. W.; Xu, M.; Duan, X. R.

    2017-11-01

    Multi-scale interactions have been observed recently in the HL-2A core NBI plasmas, including the synchronous coupling between m/n=1/1 kink mode and m/n=2/1 tearing mode, nonlinear couplings of TAE/BAE and m/n=2/1 TM near q=2 surface, AITG/KBM/BAE and m/n=1/1 kink mode near q=1 surface, and between m/n=1/1 kink mode and high-frequency turbulence. Experimental results suggest that several couplings can exist simultaneously, Alfvenic fluctuations have an important contribution to the high-frequency turbulence spectra, and the couplings reveal the electromagnetic character. Multi-scale interactions via the nonlinear modulation process maybe enhance plasma transport and trigger sawtooth-crash onset.

  14. Mixed-Language High-Performance Computing for Plasma Simulations

    Directory of Open Access Journals (Sweden)

    Quanming Lu

    2003-01-01

    Full Text Available Java is receiving increasing attention as the most popular platform for distributed computing. However, programmers are still reluctant to embrace Java as a tool for writing scientific and engineering applications due to its still noticeable performance drawbacks compared with other programming languages such as Fortran or C. In this paper, we present a hybrid Java/Fortran implementation of a parallel particle-in-cell (PIC algorithm for plasma simulations. In our approach, the time-consuming components of this application are designed and implemented as Fortran subroutines, while less calculation-intensive components usually involved in building the user interface are written in Java. The two types of software modules have been glued together using the Java native interface (JNI. Our mixed-language PIC code was tested and its performance compared with pure Java and Fortran versions of the same algorithm on a Sun E6500 SMP system and a Linux cluster of Pentium~III machines.

  15. Optimization and Control of Burning Plasmas Through High Performance Computing

    Energy Technology Data Exchange (ETDEWEB)

    Pankin, Alexei

    2017-12-18

    This project has revived the FACETS code, that has been developed under SciDAC fund- ing in 2008-2012. The code has been dormant for a number of years after the SciDAC funding stopped. FACETS depends on external packages. The external packages and libraries such as PETSc, FFTW, HDF5 and NETCDF that are included in FACETS have evolved during these years. Some packages in FACETS are also parts of other codes such as PlasmaState, NUBEAM, GACODES, and UEDGE. These packages have been also evolved together with their host codes which include TRANSP, TGYRO and XPTOR. Finally, there is also a set of packages in FACETS that are being developed and maintained by Tech-X. These packages include BILDER, SciMake, and FcioWrappers. Many of these packages evolved significantly during the last several years and FACETS had to be updated to synchronize with the re- cent progress in the external packages. The PI has introduced new changes to the BILDER package to support the updated interfaces to the external modules. During the last year of the project, the FACETS version of the UEDGE code has been extracted from FACETS as a standalone package. The PI collaborates with the scientists from LLNL on the updated UEDGE model in FACETS. Drs. T. Rognlien, M. Umansky and A. Dimits from LLNL are contributing to this task.

  16. Conceptual design of cesium removal device for ITER NBI maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Oka, Kiyoshi; Shibanuma, Kiyoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2003-03-01

    Cesium is required in order to generate a stable negative ion of hydrogen in an ion source of the neutral beam injector (NBI), which is one of the plasma-heating devices for International Thermonuclear Experimental Reactor (ITER). After long time operation of the NBI, the cesium deposits to the insulators supporting the electrode. Due to the deterioration of the insulation resistance, the continuous operation of the NBI will be difficult. In addition, the NBI device is activated by neutrons from D-T plasma, so that periodic removal and cleaning of the cesium on the insulators by remove handling is required. A study of the cesium removal scenario and the device is therefore required considering remote handling. In this report, a cesium removal procedure and conceptual design of the cesium removal device using laser ablation technique are studied, and the feasibility of the laser ablation method is shown. (author)

  17. Simple high-performance liquid chromatographic method to analyse megazol in human and rat plasma

    OpenAIRE

    Enanga, Bertin; Labat, Christian; Boudra, Hamid; Chauvière, G; Keita, M; Bouteille, B.; Dumas, Michel; Houin, Georges

    1997-01-01

    A simple and sensitive high-performance liquid chromatographic method has been developed to measure megazol in human plasma. The method was optimized and validated according to the Washington Concensus Conference on the Validation of Analytical Methods (V.P. Shah et al., Eur. J. Drug Metab. Pharmacokinet., 15 (1991) 249). The criteria of complete validation were specificity, linearity, precision, analytical recovery, dilution and stability. It involved extraction of the plasma with dichlorome...

  18. National Bridge Inventory (NBI) Bridges

    Data.gov (United States)

    Department of Homeland Security — The NBI is a collection of information (database) describing the more than 600,000 of the Nation's bridges located on public roads, including Interstate Highways,...

  19. HIGH PERFORMANCE LIQUID CHROMATOGRAPHY METHOD FOR DETERMINATION OF NIFEDIPINE IN HUMAN PLASMA

    Directory of Open Access Journals (Sweden)

    MOHAMMAD ABDOLLAHI

    1999-10-01

    Full Text Available A relatively simple normal phase high performance liquid chromatography (HPLC method was modified for determination of nifedipine in human plasma. The method is based on ultraviolet detection at 235 nm and acidic plasma extraction by a mixture of dichioromethane (30% and n-hexane (70% using nimodipine as an internal standard. The system was stabilized with the use of n-hexane (80%, chloroform (17% and methanol (3% as mobile phase. The assay was linear up to at least 120 ng/ml of nifedipine in plasma. The limit of reliable determination was at least 3 ng/ml plasma. The reproducibility of the method was satisfactory. The procedure can be used effectively to quantitate nifedipine in the human plasma.

  20. Simultaneous high-performance liquid chromatographic determination of suxibuzone and its metabolites in plasma and urine.

    Science.gov (United States)

    Marunaka, T; Shibata, T; Minami, Y; Umeno, Y; Shindo, T

    1980-11-01

    A high-performance liquid chromatographic method is described for the simultaneous determination of the anti-inflammatory agent suxibuzone and its metabolites, 4-hydroxymethylphenylbutazone, phenylbutazone, oxyphenbutazone, and gamma-hydroxyphenylbutazone, in plasma and urine. Acidified plasma or urine is extracted with benzenecyclohexane (1:1). The organic extract is reduced to dryness and the resulting residue is redissolved in methanol. Aliquots of this solution are chromatographed on a reversed-phase column using a mobile phase of methanol--0.5 M KH2PO4 (linear gradient from 0 to 100% methanol at 8% min with a flow rate of 2.0 ml/min) on a high-performance liquid chromatograph equipped with a UV absorbance detector (254 nm). Detection is limited to 0.10 microgram/ml for suxibuzone and 4-hydroxymethylphenylbutazone and to 0.05 microgram/ml for the other metabolites.

  1. Coupling nanoliter high-performance liquid chromatography to inductively coupled plasma mass spectrometry for arsenic speciation.

    Science.gov (United States)

    Cheng, Heyong; Shen, Lihuan; Liu, Jinhua; Xu, Zigang; Wang, Yuanchao

    2017-12-23

    Nanoliter high-performance liquid chromatography shows low consumption of solvents and samples, offering one of the best choices for arsenic speciation in precious samples in combination with inuctively coupled plasma mass spectrometry. A systematic investigation on coupling nanoliter high-performance liquid chromatography to inductively coupled plasma mass spectrometry from instrument design to injected sample volume and mobile phase was performed in this study. Nanoflow mobile phase was delivered by flow splitting using a conventional high-pressure pump with reuse of mobile phase waste. Dead volume was minimized to 60 nL for the sheathless interface based on the previously developed nanonebulizer. Capillary columns for nanoliter high-performance liquid chromatography were found to be sensitive to sample loading volume. An apparent difference was also found between the mobile phases for nanoliter and conventional high-performance liquid chromatography. Baseline separation of arsenite, arsenate, monomethylarsenic, and dimethylarsenic was achieved within 11 min on a 15 cm C18 capillary column and within 12 min on a 25 cm strong anion exchange column. Detection limits of 0.9-1.8 μg/L were obtained with precisions variable in the range of 1.6-4.2%. A good agreement between determined and certified values of a certified reference material of human urine (GBW 09115) validated its accuracy along with good recoveries (87-102%). © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Advanced Plasma Shape Control to Enable High-Performance Divertor Operation on NSTX-U

    Science.gov (United States)

    Vail, Patrick; Kolemen, Egemen; Boyer, Mark; Welander, Anders

    2017-10-01

    This work presents the development of an advanced framework for control of the global plasma shape and its application to a variety of shape control challenges on NSTX-U. Operations in high-performance plasma scenarios will require highly-accurate and robust control of the plasma poloidal shape to accomplish such tasks as obtaining the strong-shaping required for the avoidance of MHD instabilities and mitigating heat flux through regulation of the divertor magnetic geometry. The new control system employs a high-fidelity model of the toroidal current dynamics in NSTX-U poloidal field coils and conducting structures as well as a first-principles driven calculation of the axisymmetric plasma response. The model-based nature of the control system enables real-time optimization of controller parameters in response to time-varying plasma conditions and control objectives. The new control scheme is shown to enable stable and on-demand plasma operations in complicated magnetic geometries such as the snowflake divertor. A recently-developed code that simulates the nonlinear evolution of the plasma equilibrium is used to demonstrate the capabilities of the designed shape controllers. Plans for future real-time implementations on NSTX-U and elsewhere are also presented. Supported by the US DOE under DE-AC02-09CH11466.

  3. Simple high-performance liquid chromatographic method to analyse megazol in human and rat plasma.

    Science.gov (United States)

    Enanga, B; Labat, C; Boudra, H; Chauvière, G; Keita, M; Bouteille, B; Dumas, M; Houin, G

    1997-08-29

    A simple and sensitive high-performance liquid chromatographic method has been developed to measure megazol in human plasma. The method was optimized and validated according to the Washington Concensus Conference on the Validation of Analytical Methods (V.P. Shah et al., Eur. J. Drug Metab. Pharmacokinet., 15 (1991) 249). The criteria of complete validation were specificity, linearity, precision, analytical recovery, dilution and stability. It involved extraction of the plasma with dichloromethane, followed by reversed-phase high-performance liquid chromatography using a Kromasil C8 column and UV detection at 360 nm. The retention times of the internal standard (tinidazol) and megazol were 6.10 and 9.60 min, respectively. The standard curve was linear from 2 ng ml-1 (limit of quantification) to 2000 ng ml-1. The coefficients of variation for all the criteria of validation were less than 6%; 85 to 92% extraction efficiencies were obtained. Megazol was stable during the storage period (one month at -20 degrees C) in plasma and for two months at 25 degrees C in standard solution. The method was tested by measuring the plasma concentration following oral administration to rat and was shown to be suitable for pharmacokinetic studies.

  4. Sensitive determination of clarithromycin in human plasma by high-performance liquid chromatography with spectrophotometric detection.

    Science.gov (United States)

    Amini, Hossein; Ahmadiani, Abolhassan

    2005-03-25

    A rapid, selective and sensitive high-performance liquid chromatographic method with spectrophotometric detection was developed for the determination of clarithromycin in human plasma. Liquid-liquid extraction of clarithromycin and norverapamil (as internal standard) from plasma samples was performed with n-hexane/1-butanol (98:2, v/v) in alkaline condition followed by back-extraction into diluted acetic acid. Chromatography was carried out using a CN column (250 mm x 4.6 mm, 5 microm) under isocratic elution with acetonitrile-50 mM aqueous sodium dihydrogen phosphate (32:68, v/v), pH 4.5. Detection was made at 205 nm and analyses were run at a flow-rate of 1.0 ml/min at 40 degrees C. The analysis time was less than 11 min. The method was specific and sensitive with a quantification limit of 31.25 ng/ml and a detection limit of 10 ng/ml in plasma. The mean absolute recovery of clarithromycin from plasma was 95.9%, while the intra- and inter-day coefficient of variation and percent error values of the assay method were all less than 9.5%. Linearity was assessed in the range of 31.25-2000 ng/ml in plasma with a correlation coefficient of greater than 0.999. The method was used to analyze several hundred human plasma samples for bioavailability studies.

  5. Determination of Duloxetine and Its Major Metabolites in Rabbit Plasma by High-Performance Liquid Chromatography

    OpenAIRE

    T. K. Laha; S. Sen; G. Mishra

    2015-01-01

    A rapid and sensitive high performance liquid chromatographic method is described for simultaneous determination of duloxetine and its major metabolites, such as 4- hydroxy duloxetine (M7), Glucuronide conjugate of 5-hydroxy-6-methoxy duloxetine (M6) and Glucuronide conjugate of dihydrodiol duloxetine (M12) in rabbit plasma. HPLC analysis was carried out on a µ-Bondapak C18 column (250 mm × 4.6 mm, 5µm particle size) using methanol: phosphate buffer (pH 7.9, 50 mM) (7:3 v/v) as the mobile pha...

  6. Simple Quantification of Pentosidine in Human Urine and Plasma by High-Performance Liquid Chromatography

    Directory of Open Access Journals (Sweden)

    Ji Sang Lee

    2017-01-01

    Full Text Available Pentosidine is an advanced glycation end-product (AGE and fluorescent cross-link compound. A simple high-performance liquid chromatographic (HPLC method was developed for the detection and quantification of pentosidine in human urine and plasma. The mobile phase used a gradient system to improve separation of pentosidine from endogenous peaks, and chromatograms were monitored by fluorescent detector set at excitation and emission wavelengths of 328 and 378 nm, respectively. The retention time for pentosidine was 24.3 min and the lower limits of quantification (LLOQ in human urine and plasma were 1 nM. The intraday assay precisions (coefficients of variation were generally low and found to be in the range of 5.19–7.49% and 4.96–8.78% for human urine and plasma, respectively. The corresponding values of the interday assay precisions were 9.45% and 4.27%. Accuracies (relative errors ranged from 87.9% to 115%. Pentosidine was stable in a range of pH solutions, human urine, and plasma. In summary, this HPLC method can be applied in future preclinical and clinical evaluation of pentosidine in the diabetic patients.

  7. A New VMAT-2 Inhibitor NBI-641449 in the Treatment of Huntington Disease.

    Science.gov (United States)

    Chen, Sheng; Zhang, Xiao-Jie; Xie, Wen-Jie; Qiu, Hong-Yan; Liu, Hui; Le, Wei-Dong

    2015-08-01

    To evaluate the effectiveness of a new VMAT-2 inhibitor NBI-641449 in controlling hyperkinetic movements of Huntington disease (HD) and to investigate its possible therapeutic effects. We applied three different doses of NBI-641449 (1, 10, 100 mg/kg/day) for 2 weeks in 4-month-old YAC128 mice and wild-type (WT) mice. Rotarod performance and locomotive activities were tested during the administration of the drug. The concentration of dopamine (DA) and its metabolites was quantified in the striatal tissues by high-performance liquid chromatography (HPLC). Neuron survival in striatum and huntingtin protein aggregates were assessed with immunostaining. Expression levels of endoplasmic reticulum (ER) stress proteins were detected by immunoblotting. Rotarod performance was significantly improved after treatment with low or middle dose of NBI-641449 in YAC128 mice. Open field test showed that NBI-641449 treatment could attenuate the increased horizontal activity (HACTV), total vertical movement, moving time, and moving distance in YAC128 mice. High dose of NBI-641449 might cause sedative effects in WT and YAC128 mice. HPLC showed that NBI-641449 caused a dose-dependent decrease of DA, 3,4-dihydroxyphenylacetic acid, and homovanillic acid levels in the striatum. NeuN and DARPP-32 immunostaining revealed that NBI-641449 had no significant effect on the neuron survival in the striatum. However, NBI-641449 treatment reduced the huntingtin protein aggregates in the cortex of YAC128 mice. In addition, the levels of ER stress proteins were increased in YAC128 mice, which can be suppressed by NBI-641449. These findings suggest that this new VMAT-2 inhibitor NBI-641449 may have therapeutic potential for the treatment of HD. © 2015 John Wiley & Sons Ltd.

  8. Comparative determination of phenytoin in plasma by fluorescence polarization immunoassay and high performance liquid chromatography.

    Science.gov (United States)

    Othman, S; al-Turk, W A; Awidi, A S; Daradkeh, T K; Shaheen, O

    1987-09-01

    The need for careful monitoring of plasma concentrations of phenytoin during use of the drug in the treatment of epilepsy is well recognized; there can be great intersubject variation in the absorption rate and clearance rate of the drug, and its therapeutic ratio is narrow. In this study, two methods for determining plasma phenytoin concentrations were compared. One, based on fluorescence polarisation immunoassay (FPIA), is utilised in a commercially-available kit. The other, our own modification of a published procedure, was based on high performance liquid chromatography (HPLC). The accuracy and precision of both methods were evaluated, and the coefficients of variation (C.V.) were calculated. The C.V.'s ranged from 0.71 to 1.86% for the FPIA method, and from 2.81 to 8.69% for the HPLC method. Corresponding bias values were 1.20 to 1.60%, and 2.81 to 8.69%, respectively. A good correlation coefficient (0.977) was obtained, but estimated phenytoin concentrations were significantly higher (95% confidence level) using the HPLC method. We conclude that both methods perform adequately for clinical purposes. The HPLC method is, however, less expensive than the FPIA method.

  9. A validated new method for nevirapine quantitation in human plasma via high-performance liquid chromatography.

    Science.gov (United States)

    Silverthorn, Courtney F; Parsons, Teresa L

    2006-01-01

    A fully validated and clinically relevant assay was developed for the assessment of nevirapine concentrations in neonate blood plasma samples. Solid-phase extraction with an acid-base wash series was used to prepare subject samples for analysis. Samples were separated by high performance liquid chromatography and detected at 280 nm on a C8 reverse-phase column in an isocratic mobile phase. The retention times of nevirapine and its internal standard were 5.0 and 6.9 min, respectively. The method was validated by assessment of accuracy and precision (statistical values 0.996) and the average recovery was 93% (n = 18). The lower limit of quantification (relative standard deviation <20%) was determined to be 25 ng/mL for 50 microL of plasma, allowing detection of as little as 1.25 ng of nevirapine in a sample. This value represents an increase in sensitivity of up to 30-fold over previously published methods. Copyright 2005 John Wiley & Sons, Ltd.

  10. Determination by high-performance liquid chromatography of phenylbutazone in samples of plasma from fighting bulls.

    Science.gov (United States)

    Marti, M I González; Sánchez, González C I; Jiménez, Hernández; Cachán, García; Castro, de Cabo M J; Cuadrado, A L Garzón

    2002-03-25

    The purpose of this study was to investigate the possible presence of phenylbutazone in plasma samples from fighting bulls killed in 2nd and 3rd category bullrings in the province of Salamanca (Spain) in 1998, 1999 and 2000. For quantitative and qualitative determination, a high-performance liquid chromatograph was used, equipped with a photodiode-array detector and setting wavelengths at 240, 254 and 284 nm. The mobile phase optimized for the simultaneous detection of dexamethasone, betamethasone, flunixin and phenylbutazone, was 0.01 M acetic acid pH 3 in methanol (35:65 v/v) at a flow rate of 1 ml/min. Plasma samples were deproteinized with 400 microl of acetonitrile and 20 microl of the supernatant were injected directly into the chromatographic system equipped with a Lichrospher 60 RP select B column and guard column. For the quantitative analysis, standard calibration curves were made in a concentration range between 0.25 and 30 microg/ml, using betamethasone as internal standard. The retention time of phenylbutazone was 8.7 +/- 0.2 min and recovery was 83%. The detection and quantification limits were 0.016 and 0.029, respectively for A=240 nm. The study results show that 17 of the 74 samples analyzed in 1998, 18 of those from 1999 and 10 of those from 2000 were positive for phenylbutazone.

  11. Determination of metformin in human plasma by high-performance liquid chromatography.

    Science.gov (United States)

    Amini, Hossein; Ahmadiani, Abolhassan; Gazerani, Parisa

    2005-09-25

    A simple, selective and sensitive high-performance liquid chromatographic method with spectrophotometric detection was developed for the determination of antihyperglycemic agent metformin in human plasma using a novel sample extraction procedure. Liquid-liquid extraction of metformin and ranitidine (as internal standard) from plasma samples was performed with 1-butanol/n-hexane (50:50, v/v) in alkaline condition followed by back-extraction into diluted acetic acid. Chromatography was carried out using a silica column (250 mmx4.6 mm, 5 microm) under isocratic elution with acetonitrile-40 mM aqueous sodium dihydrogen phosphate (25:75, v/v), pH 6. The limit of quantification (LOQ) was 15.6 ng/ml and the calibration curves were linear up to 2000 ng/ml. The mean absolute recoveries for metformin and internal standard using the present extraction procedure were 98 and 95%, respectively. The intra- and inter-day coefficient of variation and percent error values of the assay method were all less than 8.3%.

  12. A high performance charge plasma PN-Schottky collector transistor on silicon-on-insulator

    Science.gov (United States)

    Loan, Sajad A.; Bashir, Faisal; Rafat, M.; Alamoud, Abdul Rehman M.; Abbasi, Shuja A.

    2014-09-01

    In this paper, we propose a new high performance PN-Schottky collector (PN-SC) lateral bipolar junction transistor (BJT) on silicon-on-insulator (SOI). The proposed device addresses the problem of poor speed of conventional lateral PNP-BJT device by using a Schottky collector. Further, it does not use the conventional ways of ion implantation/diffusion to realize n and p type doped region. However, it uses metal electrodes of different work functions to create n and p type charge plasma in an undoped silicon film. The simulation study of the proposed lateral PN-SC bipolar charge plasma transistor on SOI (PN-SC-BCPT) device has shown a significant improvement in current gain (β), cutoff frequency (f T) and switching performance in comparison to conventional PNP-BJT and PNP-bipolar charge plasma transistor (PNP-BCPT) devices. A significantly high β is obtained in the proposed PN-SC-BCPT (˜2100) in comparison to PNP-BCPT (˜1450) and the conventional BJT (˜9) devices, respectively. It has been observed that there is 89.56% and 153.5% increase in f T for the proposed PN-SC-BCPT device (2.18 GHz) in comparison to conventional PNP-BJT (1.15 GHz) and PNP-BCPT (0.86 GHz) devices, respectively. Further, reductions of 24.6% and 15.4% in switching ON-delay and 66% and 30.76% in switching OFF-delay have been achieved in the proposed device based inverters in comparison to PNP-BCPT and the conventional BJT devices based inverters, respectively. Furthermore, the proposed device does not face doping related issues and the requirement of high temperature processing is absent.

  13. High-performance liquid chromatographic determination of levodropropizine in human plasma with fluorometric detection.

    Science.gov (United States)

    Tagliaro, F; Moffa, M; De Battisti, Z; Smith, F P; Gentile, M

    1996-10-11

    The present paper describes a new high-performance liquid chromatographic method with fluorescence detection for the analysis of levodropropizine [S-(-)-3-(4-phenylpiperazin-1-yl)-propane-1,2-diol] (Levotuss), an anti-tussive drug, in human serum and plasma. A reversed-phase separation of levodropropizine was coupled with detection of the native fluorescence of the molecule, using excitation and emission wavelengths of 240 nm and 350 nm respectively. The analytical column was packed with spherical 5 microns poly(styrene-divinylbenzene) particles and the mobile phase was 0.1 M NaH2PO4 pH 3-methanol (70:30, v/v), containing 0.5% (v/v) tetrahydrofuran. For quantitation, p-methoxylevodropropizine was used as the internal standard. Samples of 200 microliters of either serum or plasma were mixed with 200 microliters of 0.1 M Na2HPO4 pH 8.9 and extracted with 5 ml of chloroform-2-propanol (9:1, v/v). The dried residue from the organic extract was redissolved with distilled water and directly injected into the chromatograph. The limit of detection for levodropropizine, in biological matrix, was about 1-2 ng/ml, at a signal-to-noise ratio of 3. The linearity was satisfactory over a range of concentrations from 3 to 1000 ng/ml (r2 = 0.99910); within-day precision tested in the range 5-100 ng/ml as well as day-to-day reproducibility proved acceptable, with relative standard deviations better than 1% in most cases. Interferences from as many as 91 therapeutic or illicit drugs were excluded.

  14. Discovery of Stationary Operation of Quiescent H-mode Plasmas with Net-Zero NBI Torque and High Energy Confinement on DIII-D

    Science.gov (United States)

    Burrell, Keith

    2015-11-01

    Experiments this summer in DIII-D have used edge turbulence control to achieve stationary, high confinement operation without Edge Localized Mode (ELM) instabilities and with no external torque input. Eliminating the ELM-induced heat bursts and controlling plasma stability at low rotation represent two of the great challenges for fusion energy. By exploiting edge turbulence in a novel manner, we achieved outstanding tokamak performance, well above the H98 international tokamak energy confinement scaling (H98 =1.25), thus meeting an additional confinement challenge that is usually difficult at low torque. The new regime is triggered in double null plasmas by ramping the injected torque to zero and then maintaining it there. This lowers ExB rotation shear in the plasma edge, allowing low-k, broadband, electromagnetic turbulence to increase. In the H-mode edge, a narrow transport barrier usually grows until MHD instability (a peeling ballooning mode) leads to the ELM heat burst. However, the increased turbulence reduces the pressure gradient, allowing the development of a broader and thus higher transport barrier. A 60% increase in pedestal pressure and 40% increase in energy confinement result. Strong double-null plasma shaping raises the threshold for the ELM instability, allowing the plasma to reach a transport-limited state near but below the explosive ELM stability boundary. The resulting plasmas have burning-plasma-relevant betan =1.6-1.8 and run without the need for extra torque from 3D magnetic fields. To date, stationary conditions have been produced for 2 s or 12 energy confinement times, limited only by external hardware constraints. Stationary operation with improved pedestal conditions is highly significant for future burning plasma devices, since operation without ELMs at low rotation and good confinement is key for fusion energy production. Supported by the US DOE under DE-FC02-04ER54698.

  15. Determination of Posaconazole in Plasma/Serum by High-Performance Liquid Chromatography with Fluorescence Detection

    Directory of Open Access Journals (Sweden)

    Peter H. Tang

    2017-05-01

    Full Text Available A sensitive high-performance liquid chromatographic (HPLC method is described for the determination of posaconazole in human plasma/serum. The method is based on a single dilution step by treating the sample with methanol, and followed by the direct injection of the sample into the HPLC system. Posaconazole and internal standard ketoconazole in the methanol extract are subsequently analyzed by using a fluorescence (FL detector at optimized wavelengths (excitation 245 nm and emission 380 nm. The method achieves a linear detector response for peak height measurements over the concentration range of 0.1–10 µg/mL which adequately covers the therapeutic range for appropriate patient monitoring. The chromatographic time is less than 8 min per injection, an improvement over most published HPLC/FL or HPLC/UV methods. The method’s limit of quantitation, linearity, imprecision, and accuracy met all criteria required by the Guidance for Industry Bioanalytical Method Validation. In comparison to other published methods, the current method would be of interest to analytical and clinical laboratories because it employs simple, rapid, and cost-effective procedures.

  16. Arsenic speciation in soil using high performance liquid chromatography/inductively coupled plasma/mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Bass, D.A.; Yaeger, J.S.; Parish, K.J.; Crain, J.S.; Kiely, J.T.; Gowdy, M.J. [Argonne National Lab., IL (United States); Mohrman, G.B.; Besmer, M.G. [Rocky Mountain Arsenal, Commerce City, CO (United States)

    1996-08-01

    A method has been developed to identify and quantify As(III), As(V), and organoarsenic compounds in soil samples from the Rocky Mountain Arsenal (RMA) by high performance liquid chromatography/inductively coupled plasma/mass spectrometry (HPLC/ICP/MS). The soils were extracted using tetrabutylammonium hydroxide (TBAH) and sonication. The percentages of As(III), As(V), and organoarsenic species extracted from soil samples were 30, 50, and 100 respectively. The arsenic species were not altered during the extraction process. They were separated by reversed-phase, ion-pairing, HPLC using a microbore Inertsil-ODS{trademark} column. The HPLC column effluent was introduced into an ICP/MS system using a direct injection nebulizer (DIN). Detection limits of less than 1 pg were readily obtained for each arsenic species. Internal standards are recommended to increase accuracy and precision. Soil samples spiked with arsenic oxide, sodium arsenate, dimethylarsinic acid (DMAA), and chlorovinyl arsenious acid (CVAA) were extracted, identified and quantified with the HPLC/ICP/MS system. The soil samples were analyzed in support of the analytical needs of a thermal desorption treatability study being conducted at the RMA.

  17. High Performance Double-null Plasma Operation Under Radiating Divertor Conditions

    Science.gov (United States)

    Petrie, T. W.; Osborne, T.; Leonard, A. W.; Luce, T. C.; Petty, C. C.; Fenstermacher, M. E.; Lasnier, C. J.; Turco, F.; Watkins, J. G.

    2017-10-01

    We report on heat flux reduction experiments in which deuterium/neon- or deuterium/argon-based radiating mantle/divertor approaches were applied to high performance double-null (DN) plasmas (H98 1.4-1.7,βN 4 , q 95 6) with a combined neutral beam and ECH power input PIN 15 MW. When the radial location of the ECH deposition is close to the magnetic axis (e.g., ρ seeding' with respect to core dilution, energy confinement, and heat flux reduction under these conditions favors argon. Conditions that lead to an improved τE as predicted previously from ELITE code analysis, i.e., very high PIN, proximity to magnetic balance, and higher q95, are largely consistent with this data. Work was supported by the US DOE under DE-FC02-04ER54698, DE-AC52-07NA27344, DE-FG02-04ER54761, and DE-AC04-94AL85000.

  18. 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.

  19. Piezoresistive Effect in Plasma-Doping of Graphene Sheet for High-Performance Flexible Pressure Sensing Application.

    Science.gov (United States)

    Haniff, M A S M; Hafiz, S M; Huang, N M; Rahman, S A; Wahid, K A A; Syono, M I; Azid, I A

    2017-05-03

    This paper presents a straightforward plasma treatment modification of graphene with an enhanced piezoresistive effect for the realization of a high-performance pressure sensor. The changes in the graphene in terms of its morphology, structure, chemical composition, and electrical properties after the NH3/Ar plasma treatment were investigated in detail. Through a sufficient plasma treatment condition, our studies demonstrated that plasma-treated graphene sheet exhibits a significant increase in sensitivity by one order of magnitude compared to that of the unmodified graphene sheet. The plasma-doping introduced nitrogen (N) atoms inside the graphene structure and was found to play a significant role in enhancing the pressure sensing performance due to the tunneling behavior from the localized defects. The high sensitivity and good robustness demonstrated by the plasma-treated graphene sensor suggest a promising route for simple, low-cost, and ultrahigh resolution flexible sensors.

  20. Atmospheric Pressure Plasma: A High-Performance Tool for the Efficient Removal of Biofilms

    Science.gov (United States)

    Fricke, Katja; Koban, Ina; Tresp, Helena; Jablonowski, Lukasz; Schröder, Karsten; Kramer, Axel; Weltmann, Klaus-Dieter; von Woedtke, Thomas; Kocher, Thomas

    2012-01-01

    Introduction The medical use of non-thermal physical plasmas is intensively investigated for sterilization and surface modification of biomedical materials. A further promising application is the removal or etching of organic substances, e.g., biofilms, from surfaces, because remnants of biofilms after conventional cleaning procedures are capable to entertain inflammatory processes in the adjacent tissues. In general, contamination of surfaces by micro-organisms is a major source of problems in health care. Especially biofilms are the most common type of microbial growth in the human body and therefore, the complete removal of pathogens is mandatory for the prevention of inflammatory infiltrate. Physical plasmas offer a huge potential to inactivate micro-organisms and to remove organic materials through plasma-generated highly reactive agents. Method In this study a Candida albicans biofilm, formed on polystyrene (PS) wafers, as a prototypic biofilm was used to verify the etching capability of the atmospheric pressure plasma jet operating with two different process gases (argon and argon/oxygen mixture). The capability of plasma-assisted biofilm removal was assessed by microscopic imaging. Results The Candida albicans biofilm, with a thickness of 10 to 20 µm, was removed within 300 s plasma treatment when oxygen was added to the argon gas discharge, whereas argon plasma alone was practically not sufficient in biofilm removal. The impact of plasma etching on biofilms is localized due to the limited presence of reactive plasma species validated by optical emission spectroscopy. PMID:22880025

  1. Atmospheric pressure plasma: a high-performance tool for the efficient removal of biofilms.

    Directory of Open Access Journals (Sweden)

    Katja Fricke

    Full Text Available INTRODUCTION: The medical use of non-thermal physical plasmas is intensively investigated for sterilization and surface modification of biomedical materials. A further promising application is the removal or etching of organic substances, e.g., biofilms, from surfaces, because remnants of biofilms after conventional cleaning procedures are capable to entertain inflammatory processes in the adjacent tissues. In general, contamination of surfaces by micro-organisms is a major source of problems in health care. Especially biofilms are the most common type of microbial growth in the human body and therefore, the complete removal of pathogens is mandatory for the prevention of inflammatory infiltrate. Physical plasmas offer a huge potential to inactivate micro-organisms and to remove organic materials through plasma-generated highly reactive agents. METHOD: In this study a Candida albicans biofilm, formed on polystyrene (PS wafers, as a prototypic biofilm was used to verify the etching capability of the atmospheric pressure plasma jet operating with two different process gases (argon and argon/oxygen mixture. The capability of plasma-assisted biofilm removal was assessed by microscopic imaging. RESULTS: The Candida albicans biofilm, with a thickness of 10 to 20 µm, was removed within 300 s plasma treatment when oxygen was added to the argon gas discharge, whereas argon plasma alone was practically not sufficient in biofilm removal. The impact of plasma etching on biofilms is localized due to the limited presence of reactive plasma species validated by optical emission spectroscopy.

  2. Determination of plasma and brain levels of isotretinoin in mice following single oral dose by high-performance liquid chromatography.

    Science.gov (United States)

    Yang, Yongsheng; Faustino, Patrick J; Pine, P Scott; Davis, Hirsch; Grunberg, Neil; Phillips, Jennifer; Lyon, Robbe C; Yu, Lawrence X; Ciavarella, Anthony B; Del Grosso, Alfred V; Hanig, Joseph P

    2005-02-07

    An isocratic reversed-phase high-performance liquid chromatographic method was established and validated according to FDA's Guidance for Industry, "Bioanalytical Method Validation", for the determination of isotretinoin in plasma and brain tissue from mice following single and multiple oral doses of Accutane. Plasma sample preparation included deproteination with acetonitrile-perchloric acid followed by centrifugation. Brain tissue was homogenized and extracted with acetonitrile-perchloric acid followed by centrifugation. The supernatants were analyzed by high-performance liquid chromatography (HPLC). Benz[alpha]anthrancene-7,12-dione was used as the internal standard. Chromatographic separation was achieved on a C18 column using an acetonitrile-aqueous 0.5% acetic acid (85:15, v/v) elution. The average extraction efficiency was >95% for plasma and >82% for brain. The lower limit of quantification was 30 ng/mL for plasma and was 30 ng/0.1g for brain tissue, respectively. The linear range for plasma was 30-600 ng/mL, and 15-300 ng/0.1g for brain. Maximum concentrations of isotretinoin in both plasma and brain were observed at 1h after single oral dosing (25 mg/kg). The maximum concentrations in plasma and brain were 2.36 microg/mL and 0.34 microg/g, respectively. The mean area under curve (AUC) in plasma was 6.13 microg h/mL. The mean eliminate half-life in plasma was estimated as 46 min.

  3. High performance solution-deposited amorphous indium gallium zinc oxide thin film transistors by oxygen plasma treatment

    KAUST Repository

    Nayak, Pradipta K.

    2012-05-16

    Solution-deposited amorphous indium gallium zinc oxide (a-IGZO) thin film transistors(TFTs) with high performance were fabricated using O2-plasma treatment of the films prior to high temperature annealing. The O2-plasma treatment resulted in a decrease in oxygen vacancy and residual hydrocarbon concentration in the a-IGZO films, as well as an improvement in the dielectric/channel interfacial roughness. As a result, the TFTs with O2-plasma treated a-IGZO channel layers showed three times higher linear field-effect mobility compared to the untreated a-IGZO over a range of processing temperatures. The O2-plasma treatment effectively reduces the required processing temperature of solution-deposited a-IGZO films to achieve the required performance.

  4. High Performance Plasma Channel Insulators for High Power Hall Thrusters Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA missions for planetary exploration require high power, long-life Hall thrusters. However, thruster power and lifetime are limited by the erosion of plasma...

  5. Determination of total L-Ascorbic Acid by high performance liquid chromatography in human plasma

    Directory of Open Access Journals (Sweden)

    Oveisi MR

    2001-07-01

    Full Text Available The total vitamin C content in human plasma is widely accepted as an indicator of the tissue status of vitamin C. A liquid chromatography method with ultraviolet detector (264 nm for measuring ascorbic acid in human plasma was developed. A C18 reversed-phase column and cetrimide as an ion-pairing agent was employed. Ascorbic acid (AA was measured after reducing L-dehydroascorbic acid to L-ascorbic acid with dithiothreitol. The stability of the ascorbic acid in plasma, metaphosphoric acid and trichloroacetic acid was also evaluated. The analytical parameters, including linearity (1-60 µg/ml, accuracy (98.98%, repeatability (2.8% and reproducibility (7.2%, showed that the method is reliable for measuring the total vitamin C content in plasma.

  6. High-Performance Kinetic Plasma Simulations with GPUs and load balancing

    Science.gov (United States)

    Germaschewski, Kai; Ahmadi, Narges; Abbott, Stephen; Lin, Liwei; Wang, Liang; Bhattacharjee, Amitava; Fox, Will

    2014-10-01

    We will describe the Plasma Simulation Code (PSC), a modern particle-in-cell code with GPU support and dynamic load balancing capabilities. For 2-d problems, we achieve a speed-up of up to 6 × on the Cray XK7 ``Titan'' using its GPUs over the well-known VPIC code, which has been optimized for conventional CPUs with SIMD support. Our load-balancing algorithm employs a space-filling Hilbert-Peano curve to maintain locality and has shown to keep the load balanced within approximately 10% in production runs which otherwise slow down up to 5 × with only static load balancing. PSC is based on the libmrc computational framework, which also supports explicit and implicit time integration of fluid plasma models. Applications include magnetic reconnection in HED plasmas, particle acceleration in space plasmas and the nonlinear evolution of anisotropy-based kinetic instabilities like the mirror mode.

  7. Plasma-spraying synthesis of high-performance photocatalytic TiO2 coatings

    Science.gov (United States)

    Takahashi, Yasuo; Shibata, Yoshitaka; Maeda, Masakatsu; Miyano, Yasuyuki; Murai, Kensuke; Ohmori, Akira

    2014-08-01

    Anatase (A-) TiO2 is a photocatalytic material that can decompose air-pollutants, acetaldehyde, bacteria, and so on. In this study, three kinds of powder (A-TiO2 without HAp, TiO2 + 10mass%HAp, and TiO2+30mass%HAp, where HAp is hydroxyapatite and PBS is polybutylene succinate) were plasma sprayed on biodegradable PBS substrates. HAp powder was mixed with A-TiO2 powder by spray granulation in order to facilitate adsorption of acetaldehyde and bacteria. The crystal structure was almost completely maintained during the plasma spray process. HAp enhanced the decomposition of acetaldehyde and bacteria by promoting adsorption. A 10mass% HAp content was the most effective for decomposing acetaldehyde when plasma preheating of the PBS was not carried out before the plasma spraying. The plasma preheating of PBS increased the yield rate of the spray process and facilitated the decomposition of acetaldehyde by A-TiO2 coatings without HAp. HAp addition improved photocatalytic sterilization when plasma preheating of the PBS was performed.

  8. Determination of inositol hexanicotinate in rat plasma by high performance liquid chromatography with UV detection.

    Science.gov (United States)

    Liang, Dong; Ma, Jing; Wei, Bo; Poon, Ivy O; Bell, Edward C; Bates, Theodore R

    2008-02-15

    A HPLC method with UV detection at 262nm was developed to analyze inositol hexanicotinate in rat plasma. Plasma samples were extracted with an equal volume of acetonitrile, followed by dilution with mobile phase buffer (5mM phosphate buffer, pH 6.0) to eliminate any solvent effects. Inositol hexanicotinate and the internal standard (mebendazole) were separated isocratically using a mobile phase of acetonitrile/phosphate buffer (35:65, v/v, pH 6.0) at a flow rate of 1.0mL/min and a reverse-phase XTerra MS C(18) column (4.6mmx150mm, 3.5microm). The standard curve was linear over a concentration range of 1.5-100.0microg/mL of inositol hexanicotinate in rat plasma. The HPLC method was validated with intra- and inter-day precisions of 1.55-4.30% and 2.69-21.5%, respectively. The intra- and inter-day biases were -0.75 to 19.8% and 2.58-22.0%, respectively. At plasma concentrations of 1.5-100microg/mL, the mean recovery of inositol hexanicotinate was 99.6%. The results of a stability study indicated that inositol hexanicotinate was unstable in rat plasma samples, but was stable in acetonitrile extracts of rat plasma for up to 24h at 4 degrees C. The assay is simple, rapid, specific, sensitive, and reproducible and has been used successfully to analyze inositol hexanicotinate plasma concentrations in a pharmacokinetic study using the rat as an animal model.

  9. The UPSF code: a metaprogramming-based high-performance automatically parallelized plasma simulation framework

    Science.gov (United States)

    Gao, Xiatian; Wang, Xiaogang; Jiang, Binhao

    2017-10-01

    UPSF (Universal Plasma Simulation Framework) is a new plasma simulation code designed for maximum flexibility by using edge-cutting techniques supported by C++17 standard. Through use of metaprogramming technique, UPSF provides arbitrary dimensional data structures and methods to support various kinds of plasma simulation models, like, Vlasov, particle in cell (PIC), fluid, Fokker-Planck, and their variants and hybrid methods. Through C++ metaprogramming technique, a single code can be used to arbitrary dimensional systems with no loss of performance. UPSF can also automatically parallelize the distributed data structure and accelerate matrix and tensor operations by BLAS. A three-dimensional particle in cell code is developed based on UPSF. Two test cases, Landau damping and Weibel instability for electrostatic and electromagnetic situation respectively, are presented to show the validation and performance of the UPSF code.

  10. Plasma transport properties at the L-H transition and high performance phase of JET discharges

    Energy Technology Data Exchange (ETDEWEB)

    Balet, B.; Cordey, J.G.; Erba, M.; Jones, T.T.C.; Lomas, P.J.; Smeulders, P.; Springmann, E.M.; Stubberfield, P.M.; Taroni, A.; Thomsen, K. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Parail, V.V. [Kurchatov Institute, Moscow (Russian Federation)

    1994-07-01

    Numerical analysis are performed which show that both electron and ion thermal diffusivities are reduced by one order of magnitude everywhere, not only in a narrow region near separatrix during the L-H transition. There is no separate H-VH transition on JET, this transition coincides with the cessation of ELMs. In the ELM free phase ion transport in the core is close to its neoclassical value, but probably rises towards plasma edge (however still remaining much less than it was in L-mode). The best agreement with experiment is obtained with the model which simultaneously takes into account both the global reduction of Bohm type anomalous transport in plasma core and formation of temperature pedestal near plasma edge. (authors). 6 refs., 5 figs.

  11. Development of 4.6 GHz lower hybrid current drive system for steady state and high performance plasma in EAST

    Energy Technology Data Exchange (ETDEWEB)

    Liu, F.K.; Li, J.G.; Shan, J.F.; Wang, M.; Liu, L.; Zhao, L.M.; Hu, H.C.; Feng, J.Q.; Yang, Y.; Jia, H.; Wang, X.J.; Wu, Z.G.; Ma, W.D.; Huang, Y.Y.; Xu, H.D.; Zhang, J.; Cheng, M.; Xu, L.; Li, M.H.; Li, Y.C.; and others

    2016-12-15

    In order to achieve steady state and high performance plasma in EAST, a new lower hybrid current drive system at a frequency of 4.6 GHz has been built. The system is composed of 24 continuous wave (CW) klystron amplifiers to generate 6MW/CW microwave, 24 standard rectangle waveguide transmission lines with water-cooling plate, a multi-junction grill composed of 576 active (in groups of 8) and 84 passive sub-waveguides arranged in 12 rows and 6 columns, and four sets of high voltage power supplies. The power value and the spectrum of the launched microwave from the antenna can be controlled by the low-power microwave circuits in front of the klystrons. The new LHCD system has been applied to the experiments on EAST tokmak since 2014, and the obtained results suggest that it is effective to couple the wave into plasma and drive plasma current.

  12. A novel remote plasma sputtering technique for depositing high-performance optical thin films

    Science.gov (United States)

    Bu, Y. K.; Liu, Z.; Dutson, J. D.; Thwaites, M. J.; Chen, N.; Cai, Z. P.

    2011-02-01

    This paper describes a novel remote plasma sputtering technique for depositing optical thin films. This technology is based on generating intensive plasma remotely from the target and then magnetically steering the plasma to the target to realize the sputter deposition. It overcomes several of inherent limitations in conventional sputtering techniques and realizes the fully uniform erosion over the surface of the target and less target poison. This allows a uniform reaction in the plasma phase when performing reactive sputtering, leading to the formation and deposition of material with a uniform stoichiometry and gives pseudo-independence of target current and voltage. This pseudo-independence offers a great deal of flexibility with regard to the control of growth conditions and film properties, the benefits include control of stress, very low deposition rates for ultra thin films. By remote reactive sputtering, dense metal-oxide optical thin films (SiO2, Ta2O5, Nb2O5) with a high deposition rate, excellent optical properties are achieved. High process stability shows an excellent time terminating accuracy for multilayer coating thickness control. Typically, thin film thickness control to coating, including anti-reflection, dichroic mirror and 2μm laser mirrors are presented.

  13. Plasma nitriding induced growth of Pt-nanowire arrays as high performance electrocatalysts for fuel cells

    NARCIS (Netherlands)

    Du, S.; Lin, K.; Malladi, S.R.K.; Lu, Y.; Sun, S.; Xu, Q.; Steinberger-Wilckens, R.; Dong, H.

    2014-01-01

    In this work, we demonstrate an innovative approach, combing a novel active screen plasma (ASP) technique with green chemical synthesis, for a direct fabrication of uniform Pt nanowire arrays on large-area supports. The ASP treatment enables in-situ N-doping and surface modification to the support

  14. High performance liquid chromatography method for rapid and accurate determination of homocysteine in plasma and serum

    DEFF Research Database (Denmark)

    Vester, Birte; Rasmussen, K

    1991-01-01

    Determination of homocysteine in plasma or serum for evaluation of cobalamin and folate deficiency is becoming an important diagnostic procedure. Accurate, rapid and low cost methods for measuring homocysteine are therefore required. We have improved an HPLC method and made it suitable for clinical...

  15. High-performance liquid chromatographic determination of rivastigmine in human plasma for application in pharmacokinetic studies.

    Science.gov (United States)

    Amini, Hossein; Ahmadiani, Abolhassan

    2010-01-01

    A simple and reproducible HPLC method with spectrophotometric detection was developed for determination of rivastigmine in human plasma. Liquid-liquid extraction of rivastigmine and donepezil (as internal standard) from plasma samples was performed with 1-butanol/n-hexane (2:98 v/v) in alkaline condition followed by back-extraction into diluted acetic acid. Chromatography was carried out using a Silica column (250 mm × 4.6 mm, 5 μm) under isocratic elution with acetonitrile-50 mM aqueous sodium dihydrogen phosphate (17: 83 v/v, pH 3.1. Analyses were run at a flow-rate of 1.3 mL/min at of 50°C. The recovery was 90.8% and 95.7% for rivastigmine and the internal standard donepezil, respectively. The precision of the method was 2.6% to 9.1% over the concentration range of 0.5-16 ng/mL for rivastigmine in plasma with a linearity greater than 0.999. The method was specific and sensitive, with a quantification limit of 0.5 ng/mL and a detection limit of 0.2 ng/mL in plasma. The method was used for a bioequivalence study in healthy subjects.

  16. Plasma-induced nanoporous metal oxides with nitrogen doping for high-performance electrocatalysis

    Science.gov (United States)

    Wang, Min

    2017-06-01

    The oxygen evolution reaction (OER) is a critical reaction in energy storage and conversion systems such as metal-air batteries and water splitting. The current commercial OER catalysts are the noble metal based materials, which have a high cost and a limited supply. Xu et al have prepared the nanoporous N-Co3O4 materials as cost-effective and high efficient electrocatalysts for OER by N2 plasma (Xu et al 2017 Nanotechnology 28 165402). This work has successfully demonstrated the simple N2 plasma treatment to be a powerful technique to introduce the nitrogen doping and nanoporous structure in the bulk materials, enhancing the performance of electrochemical catalysis. Based on this study, more future work on developing highly porous non-precious metal-based materials with good conductivity would be promising for energy storage and conversion.

  17. A quick and easy high performance liquid chromatography method for evaluation of cefixime in human plasma

    Directory of Open Access Journals (Sweden)

    Hossein Danafar

    2015-12-01

    Full Text Available Cefixime is essential member of orally energetic third generation cephalosporin and has tremendous activity aligned with many pathogens. The virtual bioavailability of a newly industrial dispersible tablet as compared with a recognized identified formulation.  A simple and available reversed-phase HPLC method with UV detection has been urbanized and validate for cefixime evaluate in human plasma using a C18 analytical column and a mobile phase of tetrabutylammonium hydroxide (pH 6.5-acetonitrile (3:1 v/v. The detection wavelength was 280 nm. To method observed major linear response-concentration association all through the cefixime concentration range of 15-100 ng/ml, with the average accuracy within-run and between-run values of 97.29% and 99.27%. The average drug recovery from plasma was 98.2% throughout the linear concentration range. The limits of detection (LOD and quantitation (LOQ of the method were 5 and 15 ng/ml, respectively. The method is quick, easy, very steady and precise for the partition, assignment, evaluation of cefixime in human plasma.

  18. High-performance liquid chromatographic determination of aspirin and its metabolites in plasma and urine.

    Science.gov (United States)

    Bakar, S K; Niazi, S

    1983-09-01

    A simple quantitative method for the rapid determination of aspirin and its metabolites, salicylic acid, salicyluric acid, and gentisic acid, in plasma and urine using o-toluic and o-anisic acids, respectively, as internal standards was developed. Plasma proteins were precipitated by the addition of acetonitrile and, after centrifugation, the supernatant fluid was injected directly onto a reverse-phase column. The mobile phase consisted of an isocratic mixture of water, methanol, and glacial acetic acid (64:25:1, v/v/v) and the separated components were detected at 238 nm using a UV detector. Concentrations greater than or equal to 0.5 microgram/ml could be quantitated for aspirin or its metabolites in plasma. The peak heights and peak height ratios to the internal standard, o-toluic acid, were linear for the concentration range of 0.5-200 micrograms/ml. The aspirin metabolites in urine were isolated by extracting the acidified urine with either and then reextracting the material into an aqueous buffer solution at pH 7.0. Twenty microliters of the buffer extract was directly injected onto the column. The separated components were detected and quantitated at 305 nm. Concentrations greater than or equal to 5 micrograms/ml of salicyluric acid, salicylic acid, and gentisic acid could be determined accurately. The peak heights and peak height ratios to the internal standard, o-anisic acid, were found to be linear for the concentration range of 5-200 micrograms/ml in urine.

  19. A simple high-performance liquid chromatography for the determination of linezolid in human plasma and saliva.

    Science.gov (United States)

    Hara, Shuuji; Uchiyama, Masanobu; Yoshinari, Masami; Matsumoto, Taichi; Jimi, Shiro; Togawa, Atsushi; Takata, Tohru; Takamatsu, Yasushi

    2015-09-01

    Linezolid is an antimicrobial agent for the treatment of multiresistant Gram-positive infections. A practical high-performance liquid chromatography method was developed for the determination of linezolid in human plasma and saliva. Linezolid and an internal standard (o-ethoxybenzamide) were extracted from plasma and saliva with ethyl acetate and analyzed on a Capcell Pak C18 MG column with UV detection at 254 nm. The calibration curve was linear through the range 0.5-50 µg/mL using a 200 μL sample volume. The intra- and interday precisions were all saliva. The accuracies ranged from 98.8 to 110% for both matrices. The mean recoveries of linezolid were 80.8% for plasma and 79.0% for saliva. This method was used to determine the plasma and saliva concentrations of linezolid in healthy volunteers who were orally administered a 600 mg dose of linezolid. Our liquid-liquid extraction procedure is easy and requires a small volume of plasma or saliva (200 μL). This small volume can be advantageous in clinical pharmacokinetic studies, especially if children participate. Copyright © 2015 John Wiley & Sons, Ltd.

  20. "Determination of mycophenolic acid in human plasma by high-performance liquid chromatography"

    Directory of Open Access Journals (Sweden)

    "Mehdi Ahadi Barzoki

    2005-05-01

    Full Text Available A simple, sensitive and reproducible HPLC method is presented for determination of mycophenolic acid(MPA in human plasma. Samples were prepared after precipitation of the plasma protein by addition of acetonitrile and naproxen was used as internal standard (I.S.. Separation was performed by reversedphase HPLC, using a Hamilton PRP-C18 Column, 51% acetonitrile and 49% potassium phosphate buffer (20 mM at pH 3.0 as mobile phase, flow rate of 1.0 ml/min, and UV detection at 215 nm. MPA and I.S. had retention times of 7.5 and 11.35 min, respectively. The method showed an acceptable linearity in the range of 0.1µg/ml-40µg/ml with r2 of .9992. The concentration of 0.1µg/ml was determined as quantification limit. Mean absolute recovery was 94.8%. The mean intra- and inter-day reproducibility of method was 4.6 and 11.4% respectively.

  1. High-Performance Liquid Chromatographic-Tandem Mass Spectrometric Determination of Itraconazole in Human Plasma for Bioavailability and Bioequivalence Studies

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Young Wook; Nam, Dae Young; Kang, Kyoung Hoon; Ha, Kyung Wook; Han, In Hee; Chang, Byung Kon; Yoon, Mi Kyeong; Lee, Jae Hwi [Chung-Ang University, Seoul (Korea, Republic of)

    2006-02-15

    A highly sensitive high-performance liquid chromatographic-tandem mass spectrometric method (HPLC-MSMS) has been developed to quantify itraconazole in human plasma for the purpose of pharmacokinetic studies. Sample preparation was carried out by liquid-liquid extraction using loratadine as an internal standard. Chromatographic separation used a YMC C{sub 18} column, giving an extremely fast total run time of 3 min. The method was validated and used for the bioequivalence study of itraconazole tablets in healthy male volunteers (n = 31). The lower limit of detection proved to be 0.2 ng /mL for itraconazole.

  2. Measurement of lumefantrine and its metabolite in plasma by high performance liquid chromatography with ultraviolet detection

    DEFF Research Database (Denmark)

    Khalil, Insaf F; Abildrup, Ulla; Alifrangis, Lene H

    2011-01-01

    measurement of LUM and its major metabolite the desbutyl LUM (DL) in plasma. Halofantrine was used as an internal standard. Liquid-liquid extraction of samples was carried out using hexane-ethyl acetate (70:30, v/v). Chromatographic separation was carried out on a Synergi Polar-RP column (250 mm × 300 mm......, particle size 4 µm). The mobile phase consisted of acetonitrile-0.1M ammonium acetate buffer adjusted to pH 4.9 (85:15%, v/v). Absorbance of the compounds was monitored at 335 nm using a reference wavelength of 360 nm. Absolute extraction recovery for LUM and DL were 88% and 90%, respectively. Inter...

  3. A high-performance channel engineered charge-plasma-based MOSFET with high-κ spacer

    Science.gov (United States)

    Shan, Chan; Wang, Ying; Luo, Xin; Bao, Meng-tian; Yu, Cheng-hao; Cao, Fei

    2017-12-01

    In this paper, the performance of graded channel double-gate MOSFET (GC-DGFET) that utilizes the charge-plasma concept and a high-κ spacer is investigated through 2-D device simulations. The results demonstrate that GC-DGFET with high-κ spacer can effectively improve the ON-state driving current (ION) and reduce the OFF-leakage current (IOFF). We find that reduction of the initial energy barrier between the source and channel is the origin of this ION enhancement. The reason for the IOFF reduction is identified to be the extension of the effective channel length owing to the fringing field via high-κ spacers. Consequently, these devices offer enhanced performance by reducing the total gate-to-gate capacitance (Cgg) and decreasing the intrinsic delay (τ).

  4. Toward High-Performance Coatings for Biomedical Devices: Study on Plasma-Deposited Fluorocarbon Films and Ageing in PBS

    Directory of Open Access Journals (Sweden)

    Diego Mantovani

    2010-03-01

    Full Text Available High performance coatings tailored to medical devices represent a recognised approach to modulate surface properties. Plasma-deposited fluorocarbon films have been proposed as a potential stent coating. Previous studies have shown promising adhesion properties: the 35 nm-thick film sustained plastic deformation up to 25% such as induced during the clinical implantation. In this study, the compositional and morphological changes of plasma-deposited fluorocarbon films were examined during ageing in a pseudo-physiological medium, a phosphate buffer solution (PBS, by angle-resolved XPS, FT-IR data and AFM images. The evolution of the ageing process is discussed: defluorination and crosslinking yielded an oxidized protective top layer onto the films, which showed further degradation.

  5. Plasma nitriding induced growth of Pt-nanowire arrays as high performance electrocatalysts for fuel cells

    Science.gov (United States)

    Du, Shangfeng; Lin, Kaijie; Malladi, Sairam K.; Lu, Yaxiang; Sun, Shuhui; Xu, Qiang; Steinberger-Wilckens, Robert; Dong, Hanshan

    2014-09-01

    In this work, we demonstrate an innovative approach, combing a novel active screen plasma (ASP) technique with green chemical synthesis, for a direct fabrication of uniform Pt nanowire arrays on large-area supports. The ASP treatment enables in-situ N-doping and surface modification to the support surface, significantly promoting the uniform growth of tiny Pt nuclei which directs the growth of ultrathin single-crystal Pt nanowire (2.5-3 nm in diameter) arrays, forming a three-dimensional (3D) nano-architecture. Pt nanowire arrays in-situ grown on the large-area gas diffusion layer (GDL) (5 cm2) can be directly used as the catalyst electrode in fuel cells. The unique design brings in an extremely thin electrocatalyst layer, facilitating the charge transfer and mass transfer properties, leading to over two times higher power density than the conventional Pt nanoparticle catalyst electrode in real fuel cell environment. Due to the similar challenges faced with other nanostructures and the high availability of ASP for other material surfaces, this work will provide valuable insights and guidance towards the development of other new nano-architectures for various practical applications.

  6. Simple and sensitive high performance liquid chromatographic method for the simultaneous quantitation of the phenylalanine in human plasma

    Directory of Open Access Journals (Sweden)

    Hossein Danafar

    2015-09-01

    Full Text Available Phenylalanine (Phe is the most reliable indicator for the diagnosis of phenylketonuria (PKU. The purpose of this study is to establish a reliable and quick method for the assignment of Phe in peripheral capillary blood from newborns and children by high performance liquid chromatography with ultraviolet detection (HPLC-UV. PKU is an inborn error of metabolism characterized by the inability of the body to use Phe. A rapid and sensitive high performance liquid chromatographic (HPLC method has been developed for determination of Phe in plasma. The method uses a protein precipitation step with sulfosalicilic acid for sample preparation by separation on a Nova-pack C18 column using sodium acetate buffer and acetonitrile (94: 6 v/v adjusted to pH 6.5 with glacial acetic acid. The eluted peaks detected by a UV detector was set at wavelength of 215 nm. The method was validated in the range of Phe concentrations from 0.1 to 20 µg/ml. The limits of detection (LOD and quantitation (LOQ of the method were 0.05 and 0.1 µg/ml, respectively. The average drug recovery from plasma was 88.60 percent throughout the linear concentration range., with the average within-run and between-run accuracy values of 103.3 and 115.350, respectively. The method is quick, easy, very steady and precise for the screen, assignment, and evaluation of Phe in human plasma by HPLC, which is particularly a useful way for screening and diagnosis of PKU and monitoring of a diet therapy.

  7. Optimized method for the determination of itopride in human plasma by high-performance liquid chromatography with fluorimetric detection.

    Science.gov (United States)

    Ptácek, Pavel; Klíma, Josef; Macek, Jan

    2009-03-15

    A high-performance liquid chromatographic method with fluorescence detection for the determination of itopride in human plasma is reported. The sample preparation was based on liquid-liquid extraction of itopride from plasma with t-butylmethylether and dichloromethane (70:30, v/v) mixture followed by a back extraction of the analyte to the phosphate buffer (pH 3.2). Liquid chromatography was performed on an octadecylsilica column (55 mm x 4 mm, 3 microm particles), the mobile phase consisted of acetonitrile-triethylamine-15 mM dihydrogenpotassium phosphate (14.5:0.5:85, v/v/v), pH of the mobile phase was adjusted to 4.8. The run time was 3 min. The fluorimetric detector was operated at 250/342 nm (excitation/emission wavelength). Naratriptan was used as the internal standard. The limit of quantitation was 9.5 ng/ml using 0.5 ml of plasma. The method precision and inaccuracy were less than 8%. The assay was applied to the analysis of samples from a bioequivalence study.

  8. Quantitation of Pyrrole-Imidazole Polyamide in Rat Plasma by High-Performance Liquid Chromatography Coupled with UV Detection

    Directory of Open Access Journals (Sweden)

    Tomonori Kamei

    2012-01-01

    Full Text Available A simple and robust method using high-performance liquid chromatography with UV detection was developed and validated for the determination of six pyrrole-imidazole (PI polyamides (HN.49, TGF-β1f, TGF-β1t, HN.50f, HN.50t, and LOX-1 in rat plasma. After the plasma proteins were precipitated with methanol containing phenacetin as an internal standard, the analytes were separated on a Luna C18 (2 (5 μm, 4.6×150 mm. Calibration curves were linear over the range of 0.5 to 200 μg/mL for HN.49, 0.25 to 200 μg/mL for TGF-β1f, TGF-β1t, HN.50t, and LOX-1, 1 to 200 μg/mL for HN.50f in rat plasma. The inter- and intraday precision were below 15%, and the accuracy was within 15% at the quality controls. The validated method was successfully applied to sample analysis for the pharmacokinetic study.

  9. Simultaneous determination of dapsone, monoacetyldapsone and pyrimethamine in whole blood and plasma by high-performance liquid chromatography

    DEFF Research Database (Denmark)

    Lemnge, M M; Rønn, A; Flachs, H

    1993-01-01

    A sensitive, selective and rapid reversed-phase high-performance liquid chromatographic method was developed for the simultaneous analysis of dapsone, monoacetyldapsone and pyrimethamine in human whole blood and plasma. The procedure involved extraction of the compounds and the internal standard...... absorbance was monitored at 286 nm. The limit of determination using a 150-microliters sample was 10 ng/ml (40 nM) for dapsone and pyrimethamine and 8 ng/ml (28 nM) for monoacetyldapsone. Given that only a small amount of blood is required in this method, it could now be applied in studies involving blood...... level monitoring and pharmacokinetics in children on Maloprim (dapsone-pyrimethamine) prophylaxis in malaria endemic areas....

  10. Analysis of native human plasma proteins and haemoglobin for the presence of bityrosine by high-performance liquid chromatography

    DEFF Research Database (Denmark)

    Daneshvar, B; Frandsen, H; Dragsted, L O

    1997-01-01

    fluorescent substance, bityrosine. High-performance liquid chromatography (HPLC) analysis of acid hydrolyzed serum albumin after oxidation with peroxidase/H2O2 or with Cu++/H2O2 showed that bityrosine had been formed whereas oxidation of this protein with Fe(III)/ascorbate did not result in the formation......Generation of reactive oxygen species in vivo results in oxidative-damage to cellular components, including proteins. Due to the relatively long half-lives of several blood proteins the cumulative formation of oxidatively damaged proteins might serve as a biomarker for reactive oxygen species...... of bityrosine. Bityrosine could not be detected in human plasma proteins or haemoglobin with the detection limit of one pmol per mg protein....

  11. Cobalamin speciation using reversed-phase micro-high-performance liquid chromatography interfaced to inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Yanes, Enrique G. E-mail: yanes@bhnrc.usda.gov; Miller-Ihli, Nancy J. E-mail: miller-ihli@bhnrc.usda.gov

    2004-06-18

    Micro-high-performance liquid chromatography interfaced to inductively coupled plasma mass spectrometry was optimized for the determination and separation of a mixture of cobalt containing species. Four cobalamin species (cyanocobalamin, hydroxocobalamin, methylcobalamin, and 5'-deoxyadenosylcobalamin) representing the various forms of vitamin B12 as well as the harmful corrinoid analogue cobinamide dicyanide were separated using reversed-phase microcapillary chromatography with columns containing C18 packing material with a 2-{mu}m particle size. Selection of organic solvents for the separation took into consideration compatibility with the inductively coupled plasma mass spectrometer being used for element specific detection. Optimized method conditions included use of a methanol gradient and make-up solution for the nebulizer. Some issues associated with dead volume were overcome by the extension of the gradient program. The total analysis time was 52 min. The column-to-column variability was evaluated and was found to be very reasonable (9% RSD on average), confirming that this method is rugged and that the technology should be easily transferred to other laboratories.

  12. Determination of hexavalent chromium in traditional Chinese medicines by high-performance liquid chromatography with inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Li, Peng; Li, Li-Min; Xia, Jing; Cao, Shuai; Hu, Xin; Lian, Hong-Zhen; Ji, Shen

    2015-12-01

    An analytical method that combined high-performance liquid chromatography with inductively coupled plasma mass spectrometry has been developed for the determination of hexavalent chromium in traditional Chinese medicines. Hexavalent chromium was extracted using the alkaline solution. The parameters such as the concentration of alkaline and the extraction temperature have been optimized to minimize the interconversion between trivalent chromium and hexavalent chromium. The extracted hexavalent chromium was separated on a weak anion exchange column in isocratic mode, followed by inductively coupled plasma mass spectrometry determination. To obtain a better chromatographic resolution and sensitivity, 75 mM NH4 NO3 at pH 7 was selected as the mobile phase. The linearity of the proposed method was investigated in the range of 0.2-5.0 μg L(-1) (r(2) = 0.9999) for hexavalent chromium. The limits of detection and quantitation are 0.1 and 0.3 μg L(-1) , respectively. The developed method was successfully applied to the determination of hexavalent chromium in Chloriti lapis and Lumbricus with satisfactory recoveries of 95.8-112.8%. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. New High-performance Liquid Chromatography-DAD Method for Analytical Determination of Arbutin and Hydroquinone in Rat Plasma.

    Science.gov (United States)

    Gallo, F R; Pagliuca, G; Multari, G; Panzini, G; D'amore, E; Altieri, I

    2015-01-01

    Natural substances present in herbal preparations should be carefully used because they can give toxic or therapeutic effects despite of their amount or the way of administration. The safety of products of vegetable origin must be assessed before commercialisation by monitoring the active ingredients and their metabolites. This study was therefore designed to identify and quantify arbutin and its metabolite hydroquinone, naturally present in Arctostaphylos uva-ursi (L.) Spreng plant in rat plasma, after an acute and subacute administration of aqueous arbutin solution in Wistar rats. For this purpose a reversed-phase high-performance liquid chromatography coupled with photodiode array detection was developed to assess the pharmacokinetic of arbutin and hydroquinone in plasma of female rats treated with aqueous arbutin solutions. The detection (arbutin: 0.0617 µg/ml and hydroquinone 0.0120 µg/ml) and quantification (arbutin: 0.2060 µg/ml and hydroquinone: 0.0400 µg/ml) limits were determined. At the arbutin concentration level of 10.7 µg/ml repeatability was 13.33% and its recovery 93.4±6.93%, while at the hydroquinone concentration level of 10.6 µg/ml repeatability was 11.66% and its recovery 92.9±7.75%. Furthermore the method was fully validated and the obtained data indicate that the new method provides good performances.

  14. [Determination of serum or plasma alpha-tocopherol by high performance liquid chromatography: optimization of operative models].

    Science.gov (United States)

    Jezequel-Cuer, M; Le Moël, G; Mounié, J; Peynet, J; Le Bizec, C; Vernet, M H; Artur, Y; Laschi-Loquerie, A; Troupel, S

    1995-01-01

    A previous multicentric study set up by the Société française de biologie clinique has emphasized the usefulness of a standardized procedure for the determination by high performance liquid chromatography of alpha-tocopherol in serum or plasma. In our study, we have tested every step of the different published procedures: internal standard adduct, lipoprotein denaturation and vitamin extraction. Reproducibility of results was improved by the use of tocol as an internal standard when compared to retinol or alpha-tocopherol acetates. Lipoprotein denaturation was more efficient with ethanol addition than with methanol and when the ethanol/water ratio was > or = 0.7. Use of n-hexane or n-heptane gave the same recovery of alpha-tocopherol. When organic solvent/water ratio was > or = 1, n-hexane enabled to efficiently extract, in a one-step procedure, the alpha-tocopherol from both normo and hyperlipidemic sera. Performances of the selected procedure were: detection limit: 0.5 microM--linear range: 750 microM--within run coefficient of variation: 2.03%--day to day: 4.76%. Finally, this pluricentric study allows us to propose an optimised procedure for the determination of alpha-tocopherol in serum or plasma.

  15. Separation and Quantification of Eight Antidiabetic Drugs on A High-Performance Liquid Chromatography: Its Application to Human Plasma Assay

    Science.gov (United States)

    Lakshmi, Karunanidhi S.; Rajesh, Tirumala

    2011-01-01

    An analytical method based on isocratic reverse phase high-performance liquid chromatography was developed and validated for the separation and quantification of eight antidiabetic drugs: rosiglitazone, pioglitazone, glipizide, gliclazide, repaglinide, nateglinide, glibenclamide, and glimepiride for their application in human plasma assay. Metformin is used as internal standard. Analysis was done on Onyx monolithic C18 column (100 × 4.6 mm, i.d., 5 μm) using a mixture of 0.05% formic acid in water and methanol in the ratio of 42 : 58 (v/v) fixed at a flow rate of 0.5 mL/min, and they were monitored at 234 nm. Separation was achieved in less than 20 min. The calibration curves were linear in the range of 50–2000 ng/mL. The method was validated for its recovery, intra- and interday precision, stability, specificity, and selectivity. Plasma samples were prepared using solid-phase extraction of analytes. Hence, the developed method was found to be suitable for the routine analysis of selected antidiabetic drugs in biological matrices. PMID:22389851

  16. A quantitative method for the determination of bosutinib in human plasma using high-performance liquid chromatography and ultraviolet detection.

    Science.gov (United States)

    Sumimoto, Takahiro; Nakahara, Ryosuke; Sato, Yuhki; Itoh, Hiroki

    2018-01-01

    We propose a simple, sensitive, and fast high-performance liquid chromatography ultraviolet detection (HPLC-UV) method for the quantitative determination of bosutinib in human plasma. Plasma samples were processed using an Oasis hydrophilic-lipophilic balance extraction cartridge (1 mL, 30 mg). Bosutinib and the internal standard imatinib were separated using a mobile phase of 0.5% Na2 PO4 H2 O (pH 3.5)-acetonitrile-methanol (55:25:20, v/v/v) on a CAPCELL PAK C18 MG II reversed-phase column 250 nm×4.6 nm i.d., at a flow rate of 1.0 mL/min, with ultraviolet detection at 250 nm. The calibration curve exhibited linearity over the bosutinib concentration range of 25-1500 ng/mL at 250 nm, with coefficient of variation for intraday precision of 2.42%, 6.04%, and 1.11% for 100, 250, and 1500 ng/mL, respectively, of bosutinib. The lower limit of detection was 20 ng/mL. The extraction recovery rates for bosutinib ranged from 84.36% to 85.82%. The intra- and interday precision was below 8.7%, and the accuracy ranged from -5.95% to 5.85% over the linear range. No notable matrix effects or astaticism were observed. The proposed HPLC-UV method was successfully applied as an assay to detect bosutinib in human plasma. © 2017 Wiley Periodicals, Inc.

  17. Analysis of drugs of abuse in human plasma by dispersive liquid-liquid microextraction and high-performance liquid chromatography.

    Science.gov (United States)

    Fernández, P; Regenjo, M; Bermejo, A M; Fernández, A M; Lorenzo, R A; Carro, A M

    2015-04-01

    Opioids and cocaine are widely used at present, both for recreational purposes and as drugs of abuse. This raises the need to develop new analytical methods specifically designed for the simultaneous detection of several drugs of abuse in biological samples. In this work, dispersive liquid-liquid microextraction (DLLME) was assessed as a new sample treatment for the simultaneous extraction of morphine (MOR), 6-acetylmorphine (6AM), cocaine (COC), benzoylecgonine (BZE) and methadone (MET) from human plasma. Preliminary assays were done before developing an experimental design based on a Uniform Network Doehlert which allowed the optimum extraction conditions to be identified, namely: a volume of extractant solvent (chloroform) and dispersant solvent (acetonitrile) of 220 µl and 3.2 ml, respectively; 0.2 g of NaCl as a salting-out additive; pH 10.6 and ultrasound stirring for 3.5 min. The resulting extracts were analyzed by high-performance liquid chromatography with photodiode array detection (HPLC-PDA), using an XBridge® RP18 column (250 × 4.6 mm i.d., 5 µm particle size). Calibration graphs were linear over the concentration range 0.1-10 µg ml⁻¹, and detection limits ranged from 13.9 to 28.5 ng ml⁻¹. Precision calculated at three different concentration levels in plasma was included in the range 0.1-6.8% RSD. Recoveries of the five drugs were all higher than 84% on average. Finally the proposed method was successfully applied to 22 plasma samples from heroin, cocaine and/or methadone users, and the most frequently detected drug was benzoylecgonine, followed by methadone, cocaine and morphine. Copyright © 2014 John Wiley & Sons, Ltd.

  18. Determination of metabolite of nicergoline in human plasma by high-performance liquid chromatography and its application in pharmacokinetic studies

    Directory of Open Access Journals (Sweden)

    Rong Zheng

    2012-02-01

    Full Text Available A fast, simple and sensitive high performance liquid chromatographic (HPLC method has been developed for determination of 10α-methoxy-6-methyl ergoline-8β-methanol (MDL, a main metabolite of nicergoline in human plasma. One-step liquid–liquid extraction (LLE with diethyl ether was employed as the sample preparation method. Tizanidine hydrochloride was selected as the internal standard (IS. Analysis was carried out on a Diamonsil ODS column (150 mm×4.6 mm, 5 μm using acetonitrile–ammonium acetate (0.1 mol/L (15/85, v/v as mobile phase at detection wavelength of 224 nm. The calibration curves were linear over the range of 2.288–73.2 ng/mL with a lower limit of quantitation (LLOQ of 2.288 ng/mL. The intra- and inter-day precision values were below 13% and the recoveries were from 74.47% to 83.20% at three quality control levels. The method herein described was successfully applied in a randomized crossover bioequivalence study of two different nicergoline preparations after administration of 30 mg in 20 healthy volunteers. Keywords: Nicergoline, 10α-methoxy-6-methylergoline-8β-methanol (MDL, HPLC, Plasma-drug concentration, Bioequivalence study

  19. Determination of calcium dobesilate in human plasma using ion-pairing extraction and high-performance liquid chromatography.

    Science.gov (United States)

    Róna, K; Ary, K

    2001-05-05

    A rapid, simple reversed-phase high-performance liquid chromatographic method with ultraviolet absorbance detection has been developed for the determination of calcium dobesilate in human plasma. Sample processing is based on an ion-pairing extraction with tetra-n-butylammonium hydroxide as cationic pairing ion and dichloromethane. Separation of the investigated calcium dobesilate and 2,4-dihydroxybenzoic acid as internal standard was achieved on a Discovery RP-Amide C16 analytical column with 50 mM, pH 2.5, potassium dihydrogenphosphate buffer-acetonitrile (75:25, v/v) mobile phase. The wavelength was set at 305 nm. The limit of quantitation is 100 ng/ml and the calibration curve is linear up to 50 microg/ml. Within-day and between-day precision expressed as the relative standard deviation is about 10% and the accuracy of the determination did not deviate from 100% by more than +/-10%. The developed method was found to be suitable for application in human bioequivalence studies.

  20. [Chromatographic identification and analysis of dextromoramide in the plasma by the method of high performance liquid chromatography].

    Science.gov (United States)

    Misztal, G; Przyborowski, L; Jednacz, T

    1989-01-01

    Dextromoramide and pethidine were separated and identified by thin-layer chromatography on silica gel, using ammonia and methanol (1.5:100) as the mobile phase, after previous extraction with dicthyl ether or with a mixture of n-hexane and isoamyl alcohol (98.5:1.5) from blood alkalized to pH 10.3 Dextromoramide can be revealed on the chromatograms in the amount of 0.5 micrograms and pethidine in the amount of 1 micrograms using the Dragendorff reagent. Reversed-phase TLC proved less sensitive. High-performance liquid chromatography on the column of LiChrosorb RP-18 was applied to the determination of dextromoramide in blood after extraction with diethyl ether, using methanol--phosphate buffer pH 4.5 (95:5) as the mobile phase. The determination range was of 0.5-5.0 micrograms per 2 cm3 of blood plasma (1.26.10(-8)-1.26.10(-7) mole/dm3).

  1. High performance liquid chromatography hyphenated to inductively coupled plasma mass spectrometry for V and Ni quantification as tetrapyrroles

    Energy Technology Data Exchange (ETDEWEB)

    Duyck, Christiane Beatrice, E-mail: cbduyck@vm.uff.br [Pontificia Universidade Catolica do Rio de Janeiro (PUC-Rio), R. Marques de Sao Vicente, 225, Gavea, Rio de Janeiro, RJ, 22451-900 (Brazil); Universidade Federal Fluminense (UFF), Campus do Valonguinho, Outeiro de Sao Joao Batista, s/no, 24020-150, Niteroi, RJ (Brazil); Saint' Pierre, Tatiana Dillenburg; Miekeley, Norbert [Pontificia Universidade Catolica do Rio de Janeiro (PUC-Rio), R. Marques de Sao Vicente, 225, Gavea, Rio de Janeiro, RJ, 22451-900 (Brazil); Oliveira da Fonseca, Teresa Cristina; Szatmari, Peter [Centro de Pesquisas Leopoldo A. Miguez de Mello da Petrobras (CENPES), Av. Horacio Macedo, 950, Cidade Universitaria, Rio de Janeiro, RJ, 21941-915 (Brazil)

    2011-05-15

    A method was developed for the determination of V and Ni as tetrapyrroles by High Performance Liquid Chromatography hyphenated to Inductively Coupled Plasma Mass Spectrometry (HPLC-ICP-MS) using reversed phase and elution gradient. Chlorinated solvents and tetrahydrofuran were investigated as regard to separation time and ICP-MS detection efficiencies. The final elution gradient program started from pure methanol to a mixture of 20:80 (v/v) chloroform:methanol. External quantification of V and Ni with inorganic standards by flow injection ICP-MS, used online with HPLC, resulted in 95% of recoveries. The Limits of Detection for V during methanol elution and for Ni during the 20% chloroform gradient elution were evaluated by their minimum detectable concentrations, which were, respectively, 5 {mu}g L{sup -1} and 8 {mu}g L{sup -1}. The methodology was applied to polar and resin fractions separated from a Brazilian crude oil and a sediment extract from an oil-polluted area in the Guanabara Bay, Rio de Janeiro, Brazil. Vanadium as tetrapyrroles represented the totality of V content in the polar fraction, whereas Ni was in different polar forms in the resin and sediment extract.

  2. Quantification of darunavir (TMC114) in human plasma by high-performance liquid chromatography with ultra-violet detection.

    Science.gov (United States)

    Goldwirt, Lauriane; Chhun, Stéphanie; Rey, Elisabeth; Launay, Odile; Viard, Jean-Paul; Pons, Gérard; Jullien, Vincent

    2007-10-01

    A precise and accurate high-performance liquid chromatography (HPLC) method with UV detection has been developed and validated for darunavir, a peptidic protease inhibitor. An internal standard, methylclonazepam, was added to 100 microL of plasma before a solid-phase extraction on C18 Bond Elut column. The eluted solutions were evaporated to dryness and reconstituted with 100 microL of mobile phase before being injected in the chromatographic system. The separation was performed on a C8 column using an acetonitrile and ultrapure water mixture (40:60, v/v) as mobile phase. All compounds were detected at a wavelength of 266 nm. The method was linear and validated over a concentration range of 0.25-20mg/L. The within-day precision, ranged from 3.0 to 7.9%, while the within-day accuracy ranged from -11.4 to 0.5%. The between day precision and accuracy were respectively less than 13.7 and -11.4%. The mean recovery was 75.7% for darunavir and 66.7% for methylclonazepam. This method provides a useful tool for therapeutic drug monitoring in HIV patients.

  3. Simultaneous quantification of purine and pyrimidine bases, nucleosides and their degradation products in bovine blood plasma by high performance liquid chromatography tandem mass spectrometry

    DEFF Research Database (Denmark)

    Nielsen, Charlotte Stentoft; Vestergaard, Mogens; Løvendahl, Peter

    2014-01-01

    ), and their degradation products (uric acid, allantoin, β-alanine, β-ureidopropionic acid, β-aminoisobutyric acid) in blood plasma of dairy cows. The high performance liquid chromatography-based technique coupled to electrospray ionization tandem mass spectrometry (LC–MS/MS) was combined with individual matrix...

  4. [Qualitative and quantitative analysis of amygdalin and its metabolite prunasin in plasma by ultra-high performance liquid chromatography-tandem quadrupole time of flight mass spectrometry and ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometry].

    Science.gov (United States)

    Gao, Meng; Wang, Yuesheng; Wei, Huizhen; Ouyang, Hui; He, Mingzhen; Zeng, Lianqing; Shen, Fengyun; Guo, Qiang; Rao, Yi

    2014-06-01

    A method was developed for the determination of amygdalin and its metabolite prunasin in rat plasma after intragastric administration of Maxing shigan decoction. The analytes were identified by ultra-high performance liquid chromatography-tandem quadrupole time of flight mass spectrometry and quantitatively determined by ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometry. After purified by liquid-liquid extraction, the qualitative analysis of amygdalin and prunasin in the plasma sample was performed on a Shim-pack XR-ODS III HPLC column (75 mm x 2.0 mm, 1.6 microm), using acetonitrile-0.1% (v/v) formic acid aqueous solution. The detection was performed on a Triple TOF 5600 quadrupole time of flight mass spectrometer. The quantitative analysis of amygdalin and prunasin in the plasma sample was performed by separation on an Agilent C18 HPLC column (50 mm x 2.1 mm, 1.7 microm), using acetonitrile-0.1% (v/v) formic acid aqueous solution. The detection was performed on an AB Q-TRAP 4500 triple quadrupole mass spectrometer utilizing electrospray ionization (ESI) interface operated in negative ion mode and multiple-reaction monitoring (MRM) mode. The qualitative analysis results showed that amygdalin and its metabolite prunasin were detected in the plasma sample. The quantitative analysis results showed that the linear range of amygdalin was 1.05-4 200 ng/mL with the correlation coefficient of 0.999 0 and the linear range of prunasin was 1.25-2 490 ng/mL with the correlation coefficient of 0.997 0. The method had a good precision with the relative standard deviations (RSDs) lower than 9.20% and the overall recoveries varied from 82.33% to 95.25%. The limits of detection (LODs) of amygdalin and prunasin were 0.50 ng/mL. With good reproducibility, the method is simple, fast and effective for the qualitative and quantitative analysis of the amygdalin and prunasin in plasma sample of rats which were administered by Maxing shigan decoction.

  5. QUANTITATIVE-DETERMINATION OF THE DOPAMINE AGONIST LISURIDE IN PLASMA USING HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH FLUORESCENCE DETECTION

    NARCIS (Netherlands)

    WOLTHERS, BG; KAMERBEEK, WDJV; VANBEUSEKOM, CM; ELSHOF, F; BUITENHUIS, AWD; BRUNT, EPR; LAKKE, JPWF

    1993-01-01

    An HPLC method for the determination of lisuride hydrogen maleate in plasma is described. After addition of ergotamine tartrate as internal standard, plasma is extracted with diethyl ether. Following evaporation of the solvent and redissolving in methanol the extract is injected on a silica HPLC

  6. Vitamin D analysis in plasma by high performance liquid chromatography (HPLC) with C30 reversed phase column and UV detection - easy and acetonitrile-free

    DEFF Research Database (Denmark)

    Hymøller, Lone; Jensen, Søren Krogh

    2011-01-01

    Two physiologically important forms of vitamin D exist: vitamin D2 and vitamin D3, which by liver based hydroxylase enzymes are converted to 25-hydroxyvitamin D2 and 25-hydroxyvitamin D3, respectively. These hydroxylated metabolites of vitamin D are measured in plasma to assess the vtamin D status...... of animals and humans. Therefore cheap and reliable analytical methods are very much in demand in nutritional and physiological research. After saponification and extraction of plasma or serum samples the current method uses reverse phase high performance liquid chromatography on a C30 column and with UV...

  7. Demonstration of high-performance p-type tin oxide thin-film transistors using argon-plasma surface treatments

    Science.gov (United States)

    Bae, Sang-Dae; Kwon, Soo-Hun; Jeong, Hwan-Seok; Kwon, Hyuck-In

    2017-07-01

    In this work, we investigated the effects of low-temperature argon (Ar)-plasma surface treatments on the physical and chemical structures of p-type tin oxide thin-films and the electrical performance of p-type tin oxide thin-film transistors (TFTs). From the x-ray photoelectron spectroscopy measurement, we found that SnO was the dominant phase in the deposited tin oxide thin-film, and the Ar-plasma treatment partially transformed the tin oxide phase from SnO to SnO2 by oxidation. The resistivity of the tin oxide thin-film increased with the plasma-treatment time because of the reduced hole concentration. In addition, the root-mean-square roughness of the tin oxide thin-film decreased as the plasma-treatment time increased. The p-type oxide TFT with an Ar-plasma-treated tin oxide thin-film exhibited excellent electrical performance with a high current on-off ratio (5.2 × 106) and a low off-current (1.2 × 10-12 A), which demonstrates that the low-temperature Ar-plasma treatment is a simple and effective method for improving the electrical performance of p-type tin oxide TFTs.

  8. CO2Plasma-Treated TiO2Film as an Effective Electron Transport Layer for High-Performance Planar Perovskite Solar Cells.

    Science.gov (United States)

    Wang, Kang; Zhao, Wenjing; Liu, Jia; Niu, Jinzhi; Liu, Yucheng; Ren, Xiaodong; Feng, Jiangshan; Liu, Zhike; Sun, Jie; Wang, Dapeng; Liu, Shengzhong Frank

    2017-10-04

    Perovskite solar cells (PSCs) have received great attention because of their excellent photovoltaic properties especially for the comparable efficiency to silicon solar cells. The electron transport layer (ETL) is regarded as a crucial medium in transporting electrons and blocking holes for PSCs. In this study, CO 2 plasma generated by plasma-enhanced chemical vapor deposition (PECVD) was introduced to modify the TiO 2 ETL. The results indicated that the CO 2 plasma-treated compact TiO 2 layer exhibited better surface hydrophilicity, higher conductivity, and lower bulk defect state density in comparison with the pristine TiO 2 film. The quality of the stoichiometric TiO 2 structure was improved, and the concentration of oxygen-deficiency-induced defect sites was reduced significantly after CO 2 plasma treatment for 90 s. The PSCs with the TiO 2 film treated by CO 2 plasma for 90 s exhibited simultaneously improved short-circuit current (J SC ) and fill factor. As a result, the PSC-based TiO 2 ETL with CO 2 plasma treatment affords a power conversion efficiency of 15.39%, outperforming that based on pristine TiO 2 (13.54%). These results indicate that the plasma treatment by the PECVD method is an effective approach to modify the ETL for high-performance planar PSCs.

  9. Quantitative determination of the dopamine agonist lisuride in plasma using high-performance liquid chromatography with fluorescence detection.

    Science.gov (United States)

    Wolthers, B G; Verhagen Kamerbeek, W D; van Beusekom, C M; Elshof, F; de Ruyter Buitenhuis, A W; Brunt, E P; Lakke, J P

    1993-12-08

    An HPLC method for the determination of lisuride hydrogen maleate in plasma is described. After addition of ergotamine tartrate as internal standard, plasma is extracted with diethyl ether. Following evaporation of the solvent and redissolving in methanol the extract is injected on a silica HPLC column and lisuride is monitored by fluorescence detection using an excitation wavelength of 322 nm and an emission wavelength of 405 nm. The method is sufficiently accurate and precise with a detection limit of 20 pg/ml lisuride in plasma. The usefulness of the method is demonstrated by measurements of lisuride levels after oral intake of a 0.6 mg dose of the drug by a healthy male volunteer, showing a peak level of 1266 pg/ml, 45 min after intake.

  10. High performance liquid chromatography method for quantification of the N-phenylpiperazine derivative LASSBio-579 in rat plasma

    Directory of Open Access Journals (Sweden)

    Daniela J. Conrado

    2007-01-01

    Full Text Available A rapid HPLC analytical method was developed and validated for the determination of the N-phenylpiperazine derivative LASSBio-579in plasma rat. Analyses were performed using a C18 column and elution with 20 mM sodium dihydrogen phosphate monohydrate - methanol. The analyte was monitored using a photodiode array detector (257 nm. Calibration curves in spiked plasma were linear over the concentration range of 0.3-8 mg/mL with determination coefficient > 0.99. The lower limit of quantification was 0.3 mg/mL. The applicability of the HPLC method for pharmacokinetic studies was tested using plasma samples obtained after administration of LASSBio-579 to Wistar rats, showing the specificity of the method.

  11. High-performance liquid chromatographic determination of fluconazole in plasma and its application to a bioequivalence study

    OpenAIRE

    CARLOS E.M. SOUSA; Bedor, Danilo C. G.; Sampaio Fhilo, L. C. A.; Silva, T.M.; Bonifácio, F. N.; Albuquerque, Miracy M.; Davi P. de Santana

    2011-01-01

    A sensitive and accurate HPLC-UV method for the quantification of fluconazole (FNZ) in human plasma has been developed. The sample was prepared by liquid–liquid extraction (LLE) of FNZ from plasma using ethyl acetate. Nevirapine (NVP) was used as internal standard. The chromatographic retention times of FNZ and NVP were 3.4 and 5.7 min, respectively. The lower limit of quantitation (LLOQ) was 0.5 μg/mL, and no interferences were detected in the chromatograms. The HPLC-UV method was...

  12. Determination of nifedipine in dog plasma by high-performance liquid chromatography with tandem mass spectrometric detection.

    Science.gov (United States)

    Pan, Xigui; Zhou, Shunchang; Fu, Qinqin; Hu, Xianming; Wu, Jianhong

    2014-07-01

    Nifedipine is a dihydropyridine calcium channel blocker used widely in the management of hypertension and other cardiovascular disorders. In this work, a simple, rapid and sensitive liquid chromatography/tandem mass spectrometry method was developed and validated to determine nifedipine in dog plasma using nimodipine as the internal standard. Chromatographic separation was carried out on a C₈ column. The mobile phase consisted of a mixture of acetonitrile, water and formic acid (60:40:0.2, v/v/v) at a flow rate of 0.5 mL/min. Detection was performed on a triple quadrupole tandem mass spectrometer in selected reaction monitoring mode via an atmospheric pressure chemical ionization source. The method has a lower limit of quantification of 0.20 ng/mL with consumption of plasma as low as 0.05 mL. The linear calibration curves were obtained in the concentration range of 0.20-50.0 ng/mL (r = 0.9948). The recoveries of the liquid extraction method were 74.5-84.1%. Intra-day and inter-day precisions were 4.1-8.8 and 6.7-7.4%, respectively. The quantification was not interfered with by other plasma components and the method was applied to determine nifedipine in plasma after a single oral administration of two controlled-release nifedipine tablets to beagle dogs. Copyright © 2013 John Wiley & Sons, Ltd.

  13. Measurement of deuterium-labeled phylloquinone in plasma by high-performance liquid chromatography/mass spectrometry (LC/MS)

    Science.gov (United States)

    Phylloquinone (vitamin K1) is a lipophilic compound present in plasma at low concentrations, which presents technical challenges for determining its bioavailability or metabolic fate using stable isotopes. We developed a method to simultaneously measure unlabeled and deuterium-labeled phylloquinone ...

  14. Simple O2 Plasma-Processed V2O5 as an Anode Buffer Layer for High-Performance Polymer Solar Cells

    DEFF Research Database (Denmark)

    Bao, Xichang; Zhu, Qianqian; Wang, Ting

    2015-01-01

    A simple O2 plasma processing method for preparation of a vanadium oxide (V2O5) anode buffer layer on indium tin oxide (ITO)-coated glass for polymer solar cells (PSCs) is reported. The V2O5 layer with high transmittance and good electrical and interfacial properties was prepared by spin coating...... a vanadium(V) triisopropoxide oxide alcohol solution on ITO and then O2 plasma treatment for 10 min [V2O5 (O2 plasma)]. PSCs based on P3HT:PC61BM and PBDTTT-C:PC71BM using V2O5 (O2 plasma) as an anode buffer layer show high power conversion efficiencies (PCEs) of 4.47 and 7.54%, respectively, under...... transport property of the V2O5 (O2 plasma) layer. The results indicate that an O2 plasma-processed V2O5 film is an efficient and economical anode buffer layer for high-performance PSCs. It also provides an attractive choice for low-cost fabrication of organic electronics...

  15. Sawtooth control using electron cyclotron current drive in the presence of energetic particles in high performance ASDEX Upgrade plasmas

    CERN Document Server

    Chapman, I T; Maraschek, M; McCarthy, P J; Tardini, G

    2013-01-01

    Sawtooth control using steerable electron cyclotron current drive (ECCD) has been demonstrated in ASDEX Upgrade plasmas with a significant population of energetic ions in the plasma core and long uncontrolled sawtooth periods. The sawtooth period is found to be minimised when the ECCD resonance is swept to just inside the q = 1 surface. By utilising ECCD inside q = 1 for sawtooth control, it is possible to avoid the triggering of neoclassical tearing modes, even at significnatly higher pressure than anticipated in the ITER baseline scenario. Operation at 25% higher normalised pressure has been achieved when only modest ECCD power is used for sawtooth control compared to identical discharges without sawtooth control when neo-classical tearing modes are triggered by the sawteeth. Modelling suggests that the destabilisation arising from the change in the local magnetic shear caused by the ECCD is able to compete with the stabilising influence of the energetic particles inside the q = 1 surface.

  16. Direct analysis of salicylic acid, salicyl acyl glucuronide, salicyluric acid and gentisic acid in human plasma and urine by high-performance liquid chromatography.

    Science.gov (United States)

    Liu, J H; Smith, P C

    1996-01-12

    A method for the simultaneous direct determination of salicylate (SA), its labile, reactive metabolite, salicyl acyl glucuronide (SAG), and two other major metabolites, salicyluric acid and gentisic acid in plasma and urine is described. Isocratic reversed-phase high performance liquid chromatography (HPLC) employed a 15-cm C18 column using methanol-acetonitrile-25 mM acetic acid as the mobile phase, resulting in HPLC analysis time of less than 20 min. Ultraviolet detection at 310 nm permitted analysis of SAG in plasma, but did not provide sensitivity for measurement of salicyl phenol glucuronide. Plasma or urine samples are stabilized immediately upon collection by adjustment of pH to 3-4 to prevent degradation of the labile acyl glucuronide metabolite. Plasma is then deproteinated with acetonitrile, dried and reconstituted for injection, whereas urine samples are simply diluted prior to injection on HPLC. m-Hydroxybenzoic acid served as the internal standard. Recoveries from plasma were greater than 85% for all four compounds over a range of 0.2-20 micrograms/ml and linearity was observed from 0.1-200 micrograms/ml and 5-2000 micrograms/ml for SA in plasma and urine, respectively. The method was validated to 0.2 microgram/ml, thus allowing accurate measurement of SA, and three major metabolites in plasma and urine of subjects and small animals administered salicylates. The method is unique by allowing quantitation of reactive SAG in plasma at levels well below 1% that of the parent compound, SA, as is observed in patients administered salicylates.

  17. Determination of metformin in human plasma and urine by high-performance liquid chromatography using small sample volume and conventional octadecyl silane column.

    Science.gov (United States)

    Gabr, Raniah Q; Padwal, Raj S; Brocks, Dion R

    2010-01-01

    To develop a selective and sensitive high-performance liquid chromatographic method for the determination of metformin in human plasma and urine, using a conventional reverse phase column and low specimen volume. Extraction of metformin and ranitidine (as internal standard) from plasma and urine samples (100 µL) was performed with a 1-butanol-hexane (50:50, v/v) mixture under alkaline conditions followed by back-extraction into diluted acetic acid. Chromatography was carried out using a C18 column (250 mm×4.6 mm, 5 μm). A mobile phase consisting of acetonitrile and KH2PO4 (34:66, v/v) and sodium dodecyl sulphate (3 mM) was pumped at an isocratic flow rate of 0.7 mL/min. The calibration curves were linear (>0.995) in the concentration ranges of 10-5000 and 2-2000 μg/mL for metformin in plasma and urine respectively. .The mean absolute recoveries for 100 and 1000 ng/mL metformin in plasma using the present extraction procedure were 93.7 and 88.5%, respectively. The intra- and inter-day coefficients of variation in plasma and urine were <20% at the lowest, and <16% at other concentrations. The percent error values were less than 2% in plasma while it reached ~9% in urine. The lower limits of quantification were 7.8 ng/mL and 1.6 μg/mL of metformin base in plasma and urine respectively. The method showed high calibers of sensitivity and selectivity for monitoring therapeutic concentrations of metformin in both plasma and urine based on a 0.1 ml sample size._____________________________________________________________________________________

  18. Simultaneous quantification of dabrafenib and trametinib in human plasma using high-performance liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Nijenhuis, C M; Haverkate, H; Rosing, H; Schellens, J H M; Beijnen, J H

    2016-06-05

    Dabrafenib (Tafinlar(®)) and trametinib (Mekinist(®)) are registered for the treatment of patients with BRAF V600 mutation positive unresectable or metastatic melanoma. To support therapeutic drug monitoring (TDM) and clinical pharmacological trials, an assay to simultaneously quantify dabrafenib and trametinib in human plasma using liquid chromatography tandem mass spectrometry was developed and validated. Human plasma samples were collected on an outpatient base and stored at nominally -20°C. Analytes and internal standards (stable isotope labeled compounds) were extracted with TBME. After snap freezing the samples in a dry ice-ethanol bath, the organic layer was transferred to a clean tube and evaporated under a gentle stream of nitrogen gas. The dry extract was then reconstituted with 100μL acetonitrile and 5μL of the final extract was injected and separated on a C18 column with gradient elution, and analyzed with triple quadrupole mass spectrometry in positive-ion mode. The validated assay ranges from 50 to 5000ng/mL for dabrafenib and 0.5-50ng/mL for trametinib were linear, and correlation coefficient (r(2)) of 0.996 or better. At all concentrations of both analytes the biases were within ±15% of the nominal concentrations and precisions were ≤15%. All results were within the acceptance criteria of the latest US FDA guidance and EMA guidelines on method validation. Dabrafenib was found to degrade under the influence of light in different organic solvents and at least seven degradation products were detected. In conclusion, the described method to simultaneously quantify dabrafenib and trametinib in human plasma was successfully validated and applied for therapeutic drug monitoring in cancer patients treated with dabrafenib and trametinib. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Determination of the class III antiarrhythmic drugs dronedarone and amiodarone, and their principal metabolites in plasma and myocardium by high-performance liquid chromatography and UV-detection.

    Science.gov (United States)

    Bolderman, Robert W; Hermans, J J Rob; Maessen, Jos G

    2009-06-15

    Dronedarone, a noniodinated benzofuran derivative of amiodarone, is believed to have a better side effect profile, and is currently undergoing phase III clinical trials. A novel method was developed for the determination of dronedarone and its principal metabolite debutyldronedarone in both plasma and myocardial tissue by high-performance liquid chromatography (HPLC) coupled with UV-detection. The assay was also validated for determination of amiodarone and desethylamiodarone. Samples were obtained from healthy humans (plasma) and goats (plasma and myocardium). Sample preparation included deproteinization with acetonitrile and extraction with a mixture of heptane and dichloromethane (50/50, v/v). Chromatographic separation was performed on a Pathfinder PS polymeric C18 column (50 mm x 4.6 mm, 2.5 microm) with a mobile phase of acetonitrile, isopropanol, water and ammonia (80/10/10/0.025, v/v/v/v) at a flow-rate of 1 ml/min. Calibration curves of all analytes were linear in the range of 0.01-5 microg/ml for plasma samples, with a lower limit of quantification (LLOQ) of 0.04 microg/ml. For myocardial tissue samples, linear curves of all analytes were observed in the range of 0.02-500 microg/g, with a LLOQ of 0.08 microg/g. Within- and between-day precision was amiodarone and principal metabolites in plasma as well as myocardial tissue.

  20. Homodyne reflectometer for NBI interlock on Large Helical Device

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Kenji; Ito, Yasuhiko; Kawahata, Kazuo; Tokuzawa, Tokihiko; Osakabe, Masaki; Takeiri, Yasuhiko [National Inst. for Fusion Science, Toki, Gifu (Japan); Ejiri, Akira [Tokyo Univ., Graduate School of Frontier Sciences, Tokyo (Japan)

    2001-05-01

    Neutral Beam Injection (NBI) under low density causes serious damage on vacuum vessel wall. It is necessary to stop NBI when electron density becomes lower than 1x10{sup 19} m{sup -3}. This needs reliable density monitor for NBI interlock. A three-channel homodyne reflectometer was installed on Large Helical Device (LHD) and was used for NBI interlock. 28.5, 34.9 and 40.2 GHz Gunn oscillators were used with O mode injection. Their O mode cut off density correspond to 1x10{sup 19}, 1.5x10{sup 19} and 2x10{sup 19} m{sup -3} respectively. The simple homodyne detection is presently used. When the density reaches to the cutoff density, the reflected signals are detected. The reflected signal consists of DC signal due to local and reflected power, and AC signal due to position of cut off layer and density fluctuation. Since the change of DC signal at lower and higher than cut off density was very small, root mean square (RMS) value of AC signal were used for interlock signal. This interlock system is successfully working from the beginning of the NBI experiments campaign on LHD. (author)

  1. Automated high-performance liquid chromatographic method with precolumn reduction for the determination of ubiquinol and ubiquinone in human plasma.

    Science.gov (United States)

    Wang, Q; Lee, B L; Ong, C N

    1999-04-16

    We developed a gradient HPLC method with automated precolumn reduction for direct electrochemical detection of ubiquinol-10 (CoQ10H2) and total coenzyme Q10 (TQ10) in human plasma. The concentration of ubiquinone-10 (CoQ10) was calculated by subtraction of CoQ10H2 from TQ10. Preparation of reducing agent and precolumn reduction was performed by a programmable auto-injector. The two mobile phases used were: A, 100% of methanol containing 50 mM sodium perchlorate and 10 mM perchloric acid; and B, a mixture of ethanol and tert.-butanol (80:20, v/v). Sample preparation was simply a deproteinisation process with 10-fold ethanol. A good linear relationship was obtained for CoQ10H2 concentration from 0.1 to 3 micromol/l. The detection limit was 2.5 nmol/l with an injection volume of 20 microl. The analytical recovery and reproduciblity were generally >90%. To validate the method, 18 freshly collected plasma samples of normal healthy subjects were analysed. The mean ratio of CoQ10H2/CoQ10 was 93:7. The proposed method is sensitive, reliable and can be used for clinical investigation.

  2. High performance liquid chromatography-tandem mass spectrometric determination of rupatadine in human plasma and its pharmacokinetics.

    Science.gov (United States)

    Tian, Yuan; Zhang, Jingjing; Lin, Hui; Liang, Jiabi; Zhang, Zunjian; Chen, Yun

    2008-08-05

    A simple, rapid, sensitive and selective liquid chromatographic-tandem mass spectrometric (LC-MS/MS) method was developed and validated for the quantification of rupatadine in human plasma using estazolam as internal standard (IS). Following liquid-liquid extraction, the analytes were separated using a mobile phase of methanol-ammonium acetate (pH 2.2; 5mM) (50:50, v/v) on a reverse phase C18 column and analyzed by a triple-quadrupole mass spectrometer in the positive ion and multiple reaction monitoring (MRM) mode, m/z 416-->309 for rupatadine and m/z 295-->267 for the IS. The assay exhibited a linear dynamic range of 0.1-100 ng/ml for rupatadine in human plasma. The lower limit of quantification (LLOQ) was 0.1 ng/ml with a relative standard deviation of less than 20%. Acceptable precision and accuracy were obtained for concentrations over the standard curve range. The validated LC-MS/MS method has been successfully applied to study the pharmacokinetics of rupatadine in healthy volunteers.

  3. Determination of total and unbound warfarin and warfarin alcohols in human plasma by high performance liquid chromatography with fluorescence detection.

    Science.gov (United States)

    Lomonaco, Tommaso; Ghimenti, Silvia; Piga, Isabella; Onor, Massimo; Melai, Bernardo; Fuoco, Roger; Di Francesco, Fabio

    2013-11-01

    Two analytical procedures are presented for the determination of the total content and unbound fraction of both warfarin and warfarin alcohols in human plasma. Chromatographic separation was carried out in isocratic conditions at 25°C on a C-18 reversed-phase column with a mobile phase consisting of a 70% buffer phosphate 25mM at pH=7, 25% methanol and 5% acetonitrile at a flow rate of 1.2mL/min. Fluorescence detection was performed at 390nm (excitation wavelength 310nm). Neither method showed any detectable interference or matrix effect. Inter-day recovery of the total warfarin and warfarin alcohols at a concentration level of 1000ng/mL was 89±3% and 73±3%, respectively, whereas for their unbound fraction (at a concentration level of 10ng/mL) was 66±8% and 90±7%, respectively. The intra- and inter-day precision (assessed as relative standard deviation) was alcohols, respectively. The methods were successfully applied to a pooled plasma sample obtained from 69 patients undergoing warfarin therapy. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Simple O2 plasma-processed V2O5 as an anode buffer layer for high-performance polymer solar cells.

    Science.gov (United States)

    Bao, Xichang; Zhu, Qianqian; Wang, Ting; Guo, Jing; Yang, Chunpeng; Yu, Donghong; Wang, Ning; Chen, Weichao; Yang, Renqiang

    2015-04-15

    A simple O2 plasma processing method for preparation of a vanadium oxide (V2O5) anode buffer layer on indium tin oxide (ITO)-coated glass for polymer solar cells (PSCs) is reported. The V2O5 layer with high transmittance and good electrical and interfacial properties was prepared by spin coating a vanadium(V) triisopropoxide oxide alcohol solution on ITO and then O2 plasma treatment for 10 min [V2O5 (O2 plasma)]. PSCs based on P3HT:PC61BM and PBDTTT-C:PC71BM using V2O5 (O2 plasma) as an anode buffer layer show high power conversion efficiencies (PCEs) of 4.47 and 7.54%, respectively, under the illumination of AM 1.5G (100 mW/cm(2)). Compared to that of the control device with PBDTTT-C:PC71BM as the active layer and PSS (PCE of 6.52%) and thermally annealed V2O5 (PCE of 6.27%) as the anode buffer layer, the PCE was improved by 15.6 and 20.2%, respectively, after the introduction of a V2O5 (O2 plasma) anode buffer layer. The improved PCE is ascribed to the greatly improved fill factor and enhanced short-circuit current density of the devices, which benefited from the change in the work function of V2O5, a surface with many dangling bonds for better interfacial contact, and the excellent charge transport property of the V2O5 (O2 plasma) layer. The results indicate that an O2 plasma-processed V2O5 film is an efficient and economical anode buffer layer for high-performance PSCs. It also provides an attractive choice for low-cost fabrication of organic electronics.

  5. Formation and sustainment of field reversed configuration (FRC) plasmas by spheromak merging and neutral beam injection

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Masaaki [Princeton Plasma Physics Laboratory, Princeton University Princeton, New Jersey USA (United States)

    2016-03-25

    This paper briefly reviews a compact toroid reactor concept that addresses critical issues for forming, stabilizing and sustaining a field reversed configuration (FRC) with the use of plasma merging, plasma shaping, conducting shells, neutral beam injection (NBI). In this concept, an FRC plasma is generated by the merging of counter-helicity spheromaks produced by inductive discharges and sustained by the use of neutral beam injection (NBI). Plasma shaping, conducting shells, and the NBI would provide stabilization to global MHD modes. Although a specific FRC reactor design is outside the scope of the present paper, an example of a promising FRC reactor program is summarized based on the previously developed SPIRIT (Self-organized Plasmas by Induction, Reconnection and Injection Techniques) concept in order to connect this concept to the recently achieved the High Performance FRC plasmas obtained by Tri Alpha Energy [Binderbauer et al, Phys. Plasmas 22,056110, (2015)]. This paper includes a brief summary of the previous concept paper by M. Yamada et al, Plasma Fusion Res. 2, 004 (2007) and the recent experimental results from MRX.

  6. Determination of levamisole in the plasma of patients with falciparum malaria using high-performance liquid chromatography.

    Science.gov (United States)

    Chiadmi, Fouad; Schlatter, Jöel

    2013-01-01

    The oral antihelmintic drug levamisole reduces sequestration of late stage parasites in falciparum malaria. Levamisole has been also identified as a cocaine adulterant. In the present study, authors developed a sensitive and selective HPLC-assay for the determination of levamisole in the plasma from patients with falciparum malaria. Chromatographic separation was achieved by using a C18 column and with an isocratic elution system comprising phosphate buffer and acetonitrile. The eluate was monitored at 235 nm by diode array detection. The calibration curve for levamisole was linear in the range from 50 to 2000 ng/mL (r2 > 0.999). The limit of quantification was 28 ng/mL and the inter- and intraday coefficients of variation were less than 7%. No interference from commonly prescribed malaria treatments was observed. The HPLC method is simple, rapid, and robust and is suited for monitoring levamisole patients in routine or toxicological studies.

  7. Improvement of selectivity and sensitivity by column switching in the determination of glycyrrhizin and glycyrrhetic acid in human plasma by high-performance liquid chromatography.

    Science.gov (United States)

    de Groot, G; Koops, R; Hogendoorn, E A; Goewie, C E; Savelkoul, T J; van Vloten, P

    1988-12-02

    A sensitive method is described for the simultaneous determination of glycyrrhizin and glycyrrhetic acid in human plasma. Quantitation is by high-performance liquid chromatography using ion-pair chromatography on a reversed-phase column. Variable-wavelength ultraviolet detection is employed. For the extraction of both compounds from plasma, a new solid-phase ion-pair extraction procedure using octadecylsilane columns was developed. Because of the strong forces involved in the protein binding of glycyrrhizin, quantitative extraction of this compound from plasma was possible only after an alkaline pH shift. A considerable improvement in selectivity and sensitivity was obtained by automated column switching involving on-line preseparation of the solid-phase extract on a short precolumn and chromatographic analysis of a heart-cut from the precolumn eluate. The limit of detection of both glycyrrhizin and glycyrrhetic acid was 0.1 mg/l in 0.5 ml of plasma. From a preliminary study in human volunteers, it was concluded that glycyrrhetic acid rather than glycyrrhizin is preferred in a study in human volunteers to assess the zero effect level of glycyrrhizin.

  8. High performance of hydrogen peroxide detection using Pt nanoparticles-dispersed carbon electrode prepared by pulsed arc plasma deposition.

    Science.gov (United States)

    Ito, Takeshi; Kunimatsu, Masayuki; Kaneko, Satoru; Hirabayashi, Yasuo; Soga, Masayasu; Agawa, Yoshiaki; Suzuki, Koji

    2012-09-15

    We propose novel electrodes with platinum nanoparticles dispersed on a glassy carbon (Pt-NPs/GC) prepared using a pulsed arc plasma deposition (APD) method. The method could coat Pt-NPs on a base material directly with a single-step process in a very short deposition time. The characteristics of the electrodes were discussed in detail. The detection of hydrogen peroxide was performed as an example for application of the electrodes. The distribution of nanoparticles was controlled easily by the number of pulse. The surface morphology changed with the pulse number and the annealing except for the sample prepared by 5 pulses deposition (APD(5)), implying that the APD(5) remained as NPs after the annealing. Average particle size was 2.7 nm on the Pt-NPs/GC. Catalyst activity for oxidizing hydrogen peroxide per Pt loading was excellent on the Pt-NPs/GC. When the Pt-NPs/GC was used as a detector for hydrogen peroxide on a flow injection analysis, the Pt-NPs/GC showed high sensitivity without deterioration. Oxidation current increased linearly with the concentration of hydrogen peroxide from 10nM to 100 μM. This fast and easily prepared electrode showed the capability to replace a conventional bulk metal electrode. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. High performance liquid chromatographic determination of some co-administered anticancer drugs in pharmaceutical preparations and in spiked human plasma.

    Science.gov (United States)

    Fahmy, Ossama T; Korany, Mohamed A; Maher, Hadir M

    2004-03-10

    Two HPLC methods are introduced in this paper for the simultaneous determination of doxorubicin hydrochloride (DOX) and 5-fluorouracil (5-FU), combination I, and of cytarabine (CYT) and etoposide (ETO), combination II, as co-administered drugs. In both combinations, a [250 mm x 4.6 mm C-18 column is used. The mobile phase for combination I consists of a mixture of acetonitrile and 0.05 M disodium hydrogenphosphate (50:50, v/v) containing 0.1% sodium laurylsulfate (SLS) adjusted to pH 3.7 at a flow rate 1 ml/min, with UV detection at 260 nm and ambient temperature. For combination II, the mobile phase consists of a mixture of 0.02 M sodium dihydrogenphosphate aqueous solution adjusted to pH 6.0 (with 0.2 M orthophosphoric acid or sodium hydroxide) and acetonitrile in a ratio of (7:3) at a flow rate 1 ml/min, with UV detection at 254 nm and ambient temperature. The methods also permitted the determination of methyl hydroxybenzoate (MHB) which is used as a preservative in DOX vials, combination I, and of benzyl alcohol (BZA) preservative in ETO vials, combination II. The proposed HPLC methods were successfully applied to the determination of the investigated drugs, of the two combinations, both in injection solutions and spiked human plasma samples with high precision and accuracy. Linearity, validation, accuracy, precision, limits of detection, limits of quantitation, and other aspects of analytical validation are presented in the text.

  10. A newly validated high-performance liquid chromatography method with diode array ultraviolet detection for analysis of the antimalarial drug primaquine in the blood plasma

    Directory of Open Access Journals (Sweden)

    Ana Paula Barbosa do Carmo

    Full Text Available Abstract INTRODUCTION: Primaquine (PQ diphosphate is an 8-aminoquinoline antimalarial drug with unique therapeutic properties. It is the only drug that prevents relapses of Plasmodium vivax or Plasmodium ovale infections. In this study, a fast, sensitive, cost-effective, and robust method for the extraction and high-performance liquid chromatography with diode array ultraviolet detection (HPLC-DAD-UV analysis of PQ in the blood plasma was developed and validated. METHODS: After plasma protein precipitation, PQ was obtained by liquid-liquid extraction and analyzed by HPLC-DAD-UV with a modified-silica cyanopropyl column (250mm × 4.6mm i.d. × 5μm as the stationary phase and a mixture of acetonitrile and 10mM ammonium acetate buffer (pH = 3.80 (45:55 as the mobile phase. The flow rate was 1.0mL·min-1, the oven temperature was 50OC, and absorbance was measured at 264nm. The method was validated for linearity, intra-day and inter-day precision, accuracy, recovery, and robustness. The detection (LOD and quantification (LOQ limits were 1.0 and 3.5ng·mL-1, respectively. The method was used to analyze the plasma of female DBA-2 mice treated with 20mg.kg-1 (oral PQ diphosphate. RESULTS: By combining a simple, low-cost extraction procedure with a sensitive, precise, accurate, and robust method, it was possible to analyze PQ in small volumes of plasma. The new method presents lower LOD and LOQ limits and requires a shorter analysis time and smaller plasma volumes than those of previously reported HPLC methods with DAD-UV detection. CONCLUSIONS: The new validated method is suitable for kinetic studies of PQ in small rodents, including mouse models for the study of malaria.

  11. A newly validated high-performance liquid chromatography method with diode array ultraviolet detection for analysis of the antimalarial drug primaquine in the blood plasma.

    Science.gov (United States)

    Carmo, Ana Paula Barbosa do; Borborema, Manoella; Ribeiro, Stephan; De-Oliveira, Ana Cecilia Xavier; Paumgartten, Francisco Jose Roma; Moreira, Davyson de Lima

    2017-01-01

    Primaquine (PQ) diphosphate is an 8-aminoquinoline antimalarial drug with unique therapeutic properties. It is the only drug that prevents relapses of Plasmodium vivax or Plasmodium ovale infections. In this study, a fast, sensitive, cost-effective, and robust method for the extraction and high-performance liquid chromatography with diode array ultraviolet detection (HPLC-DAD-UV ) analysis of PQ in the blood plasma was developed and validated. After plasma protein precipitation, PQ was obtained by liquid-liquid extraction and analyzed by HPLC-DAD-UV with a modified-silica cyanopropyl column (250mm × 4.6mm i.d. × 5μm) as the stationary phase and a mixture of acetonitrile and 10mM ammonium acetate buffer (pH = 3.80) (45:55) as the mobile phase. The flow rate was 1.0mL·min-1, the oven temperature was 50OC, and absorbance was measured at 264nm. The method was validated for linearity, intra-day and inter-day precision, accuracy, recovery, and robustness. The detection (LOD) and quantification (LOQ) limits were 1.0 and 3.5ng·mL-1, respectively. The method was used to analyze the plasma of female DBA-2 mice treated with 20mg.kg-1 (oral) PQ diphosphate. By combining a simple, low-cost extraction procedure with a sensitive, precise, accurate, and robust method, it was possible to analyze PQ in small volumes of plasma. The new method presents lower LOD and LOQ limits and requires a shorter analysis time and smaller plasma volumes than those of previously reported HPLC methods with DAD-UV detection. The new validated method is suitable for kinetic studies of PQ in small rodents, including mouse models for the study of malaria.

  12. [Detection of plasma and urine furosemide based on online enrichment and restricted- access media coupled with high-performance liquid chromatography].

    Science.gov (United States)

    Zhang, Xiao-Hui; Wang, Rong; Xie, Hua; Yin, Qiang; Li, Wen-Bin; Jia, Zheng-Ping; Zhang, Juan-Hong

    2014-10-01

    To establish a method based on restricted access media-high performance liquid chromatography for direct online sample injection and detection of plasma and urine furosemide in rats. The column of restricted access media was used as the pre-treatment column and a C18 column as the analytical column. The mobile phase of the pre- treatment column was water-methanol (95:5, V/V) with a volume percentage of formic acid of 0.1%. The mobile phase of the analytical column was methanol-water (65:35, V/V) for plasma and methanol-water (55:45, V/V) for urine samples, all containing a volume percentage of formic acid of 0.1% with a flow rate of 1 ml/min. The detection wavelength was 274 nm and the column temperature was maintained at 25 degrees celsius. The calibration curve showed an excellent linear relationship in rat plasma furosemide concentration range of 0.1-3.2 µg/ml (r=0.9995) and in urine concentration range of 0.5-32 µg/ml (r=0.9991). The average recoveries of furosemide at 3 spiked levels ranged from 101.82% to 113.36% for plasma and from 98.75% to 112.27% for urine samples. The detection showed good intra- and inter-day assay precisions and accuracies with the relative standard deviations all below 5%. The pharmacokinetic parameters AUC(0→24) was 6.265 g/(ml·h) with a t(1/2) of 2.447 h and a C(Max) of 1.414 g/ml. The mean cumulative excretory rate of furosemide in the urine of rats over 24 h was 32.50%-39.08%. Detection of furosemide in plasma and urine samples using restricted access media-high performance liquid chromatography is simple and efficient and allows direct online injection of the samples.

  13. Quantitative determination of famotidine in human maternal plasma, umbilical cord plasma and urine using high-performance liquid chromatography-mass spectrometry.

    Science.gov (United States)

    Wang, Xiaoming; Rytting, Erik; Abdelrahman, Doaa R; Nanovskaya, Tatiana N; Hankins, Gary D V; Ahmed, Mahmoud S

    2013-07-01

    Liquid chromatography with electrospray ionization mass spectrometry for the quantitative determination of famotidine in human urine, maternal and umbilical cord plasma was developed and validated. The plasma samples were alkalized with ammonium hydroxide and extracted twice with ethyl acetate. The extraction recovery of famotidine in maternal and umbilical cord plasma ranged from 53 to 64% and 72 to 79%, respectively. Urine samples were directly diluted with the initial mobile phase then injected into the HPLC system. Chromatographic separation of famotidine was achieved by using a Phenomenex Synergi™ Hydro-RP™ column with a gradient elution of acetonitrile and 10 mm ammonium acetate aqueous solution (pH 8.3, adjusted with ammonium hydroxide). Mass spectrometric detection of famotidine was set in the positive mode and used a selected ion monitoring method. Carbon-13-labeled famotidine was used as internal standard. The calibration curves were linear (r(2) > 0.99) in the concentration ranges of 0.631-252 ng/mL for umbilical and maternal plasma samples and 0.075-30.0 µg/mL for urine samples. The relative deviation of method was cord plasma was less than 17%. Copyright © 2013 John Wiley & Sons, Ltd.

  14. High-performance liquid chromatography-tandem mass spectrometry for the determination of pidotimod in human plasma and its application to a pharmacokinetic study.

    Science.gov (United States)

    Zhang, Yi; Xiong, Zhili; Qin, Feng; Lu, Shan; Liu, Wei; Li, Famei

    2009-08-15

    A selective, rapid and sensitive high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for the first time to determine pidotimod in human plasma and applied to a pharmacokinetic study. Diphenhydramine was used as the internal standard (I.S.). Sample pretreatment involved in one-step protein precipitation (PPT) with methanol of 0.1 mL plasma. The analysis was carried out on an Ultimate XB-C(8) column with mobile phase of methanol-water containing 0.5% formic acid (65:35, v/v). The detection was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring (MRM) mode via electrospray ionization (ESI) source. Each plasma sample was chromatographed within 4.5 min. The linear calibration curves were obtained in the concentration range of 0.05-20.00 microg/mL (r(2) > or = 0.99) with the lower limit of quantification (LLOQ) of 0.0500 microg/mL. The intra- and inter-day precision (relative standard deviation, R.S.D.) values were below 15% and accuracy (relative error, R.E.) was from -5.1% to 3.9% at all quality control (QC) levels. The method was applicable to clinical pharmacokinetic study of pidotimod in healthy volunteers after oral administration.

  15. An Ultra-High Performance Liquid Chromatographic-Tandem Mass Spectrometric Method for the Determination of Sinomenine in Human Plasma after Transdermal Delivery of the Zhengqing Fengtongning Injection

    Directory of Open Access Journals (Sweden)

    Tingbo Chen

    2015-04-01

    Full Text Available A sensitive, precise and selective ultra-high performance liquid chromatography method coupled with triple-quadrupole mass spectrometry was developed and validated for the determination of trace amounts of sinomenine (ng/mL in minute volumes of human plasma. Fifty microliter plasma samples were precipitated using methanol to extract sinomenine. Separation was carried out on a C18 column with a water and acetonitrile mobile phase gradient with formic acid as an additive. The mass spectrometry data were obtained in the positive ion mode, and the transition of multiple reactions was monitored at m/z 330.2→181.0 for sinomenine quantification. The working assay range for sinomenine was linear from 0.1173 to 15.02 ng/mL with the lower limit of quantification of 0.1173 ng/mL. The precision and accuracy of the method was less than 15% in intra-day and inter-day experiments with a matrix effect of less than 6.5%. After validation, the quantitative method was applied to analyze sinomenine levels in human plasma after transdermal delivery of the Zhengqing Fengtongning Injection. The results showed that some samples contained sinomenine within the concentration range 0.4131–4.407 ng/mL.

  16. NBI-driven Alfvenic modes at ASDEX Upgrade

    NARCIS (Netherlands)

    Lauber, P.; Classen, I.G.J.; Curran, D.; Igochine, V.; Geiger, B.; da Graca, S.; M. García-Muñoz,; Maraschek, M.; McCarthy, P.

    2012-01-01

    A large variety of electromagnetic modes excited by NBI-generated energetic ions are observed in the early phase of many discharges at ASDEX Upgrade. In addition to the well-known reversed shear Alfven eigenmodes (RSAE) and the toroidal Alfven eigenmodes (TAE), a set of modes around 70 kHz is

  17. High-performance liquid chromatographic determination of plasma triglyceride type composition in a normal population of Barcelona. Relationship with age, sex and other plasma lipid parameters.

    Science.gov (United States)

    Parreño, M; Castellote, A I; Codony, R

    1993-11-26

    A coupled TLC-HPLC procedure is proposed for the separation and determination of plasma triglycerides. The method was tested by application to plasma samples corresponding to a normal population of Barcelona (Spain). Eighteen different triglyceride types were identified and their relative proportions were established, in order to give a "normal profile" for men and women. Sex-related differences (p LOPa). A correlation study showed that palmitodiolein and total cholesterol levels increase with age, whereas LLP-LOPa decreases in men and palmitolinoleoolein + palmitooleopalmitolein in women.

  18. Development of a high-current hydrogen-negative ion source for LHD-NBI system

    Energy Technology Data Exchange (ETDEWEB)

    Takeiri, Yasuhiko; Osakabe, Masaki; Tsumori, Katsuyoshi; Oka, Yoshihide; Kaneko, Osamu; Asano, Eiji; Kawamoto, Toshikazu; Akiyama, Ryuichi [National Inst. for Fusion Science, Toki, Gifu (Japan); Tanaka, Masanobu

    1998-08-01

    We have developed a high-current hydrogen-negative ion source for a negative-ion-based NBI system in Large Helical Device (LHD). The ion source is a cesium-seeded volume-production source equipped with an external magnetic filter. An arc chamber is rectangular, the dimensions of which are 35 cm x 145 cm in cross section and 21 cm in depth. A three-grid single-stage accelerator is divided into five sections longitudinally, each of which has 154(14 x 11) apertures in an area of 25 cm x 25 cm. The ion source was tested in the negative-NBI teststand, and 25 A of the negative ion beam is incident on a beamdump 13 m downstream with an energy of 104 keV for 1 sec. Multibeamlets of 770 are focused on a focal point 13 m downstream with an averaged divergence angle of 10 mrad by the geometrical arrangement of five sections of grid and the aperture displacement technique of the grounded grid. A uniform beam in the vertical direction over 125 cm is obtained with uniform plasma production in the arc chamber by balancing individual arc currents flowing through each filament. Long-pulse beam production was performed, and 1.3 MW of the negative ion beam is incident on the beamdump for 10 sec, and the temperature rise of the cooling water is almost saturated for the extraction and the grounded grids. These results satisfy the first-step specification of the LHD-NBI system. (author)

  19. Determination of selected polybrominated diphenylethers and polybrominated biphenyl in polymers by ultrasonic-assisted extraction and high-performance liquid chromatography-inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Mingwu, Shao; Chao, Wei; Yongjuan, Jia; Xinhua, Dai; Xiang, Fang

    2010-06-15

    A new method has been developed for the determination of selected polybrominated diphenylethers (PBDEs) and polybrominated biphenyl (PBB) in four polymers: high-density polyethylene (HDPE), polystyrene (PS), acrylonitrile-butadiene-styrene copolymer (ABS), and polypropylene (PP). PBDEs and PBB in the polymers were extracted with toluene, using ultrasonic-assisted extraction (UAE). The extracts were then determined by high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS), using external calibration (single-point). Extraction parameters of UAE and several ICP-MS parameters were optimized. Extraction efficiencies almost reached 100%. The relative standard deviations (RSDs) were in the range of 0.7%-5.4%. The results demonstrate that the method possesses advantages of good precision, as well as high extraction efficiency and accuracy. The method especially overcomes the problem of the thermal degradation of highly brominated PBDEs, such as PBDE-209.

  20. Determination of torasemide in human plasma and its bioequivalence study by high-performance liquid chromatography with electrospray ionization tandem mass spectrometry

    Directory of Open Access Journals (Sweden)

    Lin Zhang

    2016-04-01

    Full Text Available A sensitive and selective method using high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (HPLC–ESI–MS to determine the concentration of torasemide in human plasma samples was developed and validated. Tolbutamide was chosen as the internal standard (IS. The chromatography was performed on a Gl Sciences Inertsil ODS-3 column (100 mm×2.1 mm i.d., 5.0 µm within 5 min, using methanol with 10 mM ammonium formate (60:40, v/v as mobile phase at a flow rate of 0.2 mL/min. The targeted compound was detected in negative ionization at m/z 347.00 for torasemide and 269.00 for IS. The linearity range of this method was found to be within the concentration range of 1–2500 ng/mL (r=0.9984 for torasemide in human plasma. The accuracy of this measurement was between 94.05% and 103.86%. The extracted recovery efficiency was from 84.20% to 86.47% at three concentration levels. This method was also successfully applied in pharmacokinetics and bioequivalence studies in Chinese volunteers.

  1. Solid-phase extraction for the high-performance liquid chromatographic determination of indomethacin, suxibuzone, phenylbutazone and oxyphenbutazone in plasma, avoiding degradation of compounds.

    Science.gov (United States)

    Caturla, M C; Cusido, E

    1992-10-02

    A solid-phase extraction method was validated for the simultaneous high-performance liquid chromatographic determination of indomethacin, suxibuzone, phenylbutazone, oxyphenbutazone and their degradation products. Indomethacin was added as internal standard to plasma samples, which were then acidified with citrate buffer and passed through a phenyl cartridge. The drugs were eluted with hexane-diethyl ether (1:1, v/v), and the organic extract was taken to dryness. The residue was dissolved in methanol and chromatographed on a C18 column with ultraviolet detection at 240 nm. The elution was isocratic with a mobile phase of 0.02 M ammonium sulphate-acetonitrile (45:55, v/v), pH 3. For indomethacin, suxibuzone, phenylbutazone and oxyphenbutazone the limit of quantitation was 0.05 microgram/ml. The linearity was checked between 0.05 and 100 micrograms/ml (r = 0.999); within this range the recovery was higher than 90% and the accuracy showed relative errors of less than 7.5%. The main advantage of this method is the avoidance of degradation by using citrate buffer instead of the usual 5 M hydrochloric acid to acidify the plasma. The method is also more specific and less time-consuming than the previously reported liquid-liquid extraction, and could possibly be automated.

  2. Simultaneous determination of MHD and DMD in dog plasma by high-performance liquid chromatography with fluorescence detection and its application to pharmacokinetic studies.

    Science.gov (United States)

    Li, Xiaoyu; Wang, Guangji; Xie, Haitang; Wang, Rui; Xu, Meijuan; Wang, Wei; Tao, Jining; Sun, Jianguo

    2006-02-01

    A rapid, reproducible high-performance liquid chromatographic (HPLC) method with fluorescence detection for the simultaneous determination of 3(or 8)-(1-methoxyethyl)-8(or 3)-(1-hydroxyethyl)-deuteroporphyrin IX (MHD) and 3,8-di-(1-methoxyethyl)-deuteroporphyrin IX (DMD) in dog plasma was described. Fluorescein was used as an internal standard. A simple extraction step with ethyl acetate was performed before chromatography on a Diamonsil C18 column (5 microm, 4.6 mm x 150 mm). The chromatography used 0.02 mol L(-1) sodium acetate/tetrahydrofuran (66:34 v/v). The analytical curve was linear over the concentration range 0.025-2.5 microg mL(-1). For a 100 microL dog plasma sample, the limit of determination for both MHD and DMD was 0.025 microg mL(-1). The recoveries of MHD and DMD were more than 76% and 89%, respectively. The intra-assay (within-run) and interassay (between-run) coefficients of variation (precisions) for MHD and DMD were less than 15%. This method was found to be suitable for the analysis of biosamples and was successfully applied to pharmacokinetic studies of Deuxemether in dogs.

  3. Low-density solvent-based dispersive liquid-liquid microextraction followed by high performance liquid chromatography for determination of warfarin in human plasma.

    Science.gov (United States)

    Ghambari, Hoda; Hadjmohammadi, Mohammadreza

    2012-06-15

    Extraction and determination of warfarin, a widely used anticoagulant drug, in human plasma were performed using a new generation of dispersive liquid-liquid microextraction (DLLME) and high performance liquid chromatography (HPLC). The extraction procedure is based on extraction solvents lighter than water and performing of extraction in a specially designed extraction cell. Some important parameters, including kind and volume of extraction and disperser solvents, pH of the sample solution, salt concentration in the sample solution and extraction time were investigated and optimized. Under the optimized conditions (150 μL 1-octanol as extraction solvent, 150 μL methanol as disperser solvent, pH(sample)=2.3, extraction time of 2 min, without salt addition), limit of detection (LOD) of 5 ng mL⁻¹ and extraction recovery of 91.0% were obtained. The calibration curve was linear within the range of 15-3000 ng mL⁻¹ with the square of correlation coefficient (R²) of 0.998. Repeatability and reproducibility of method based on five replicate extraction and determination were 2.8% and 6.5%, respectively. The proposed method was applied successfully for the determination of warfarin in plasma sample from a patient under treatment with this drug, and was demonstrated to be sensitive, efficient, and convenient. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Measurement of ethyl methanesulfonate in human plasma and breast milk samples using high-performance liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry.

    Science.gov (United States)

    Montesano, M Angela; Whitehead, Ralph D; Jayatilaka, Nayana K; Kuklenyik, Peter; Davis, Mark D; Needham, Larry L; Barr, Dana Boyd

    2010-06-05

    Ethyl methanesulfonate (EMS) is a mesylate ester, which is known to be a potent mutagen, teratogen, and possibly carcinogen. Mesylate esters have been found in pharmaceuticals as contaminants formed during the manufacturing process and may potentially pose an exposure hazard to humans. We have developed and validated a method for detection of trace amounts (ng/ml levels) of EMS in human plasma and breast milk. The samples were extracted by matrix solid-phase dispersion with ethyl acetate using Hydromatrix and the ASE 200 Accelerated Solvent Extractor. The extracts were separated by high-performance liquid chromatography (HPLC) using a HILIC column. The detection was performed with a triple quadrupole mass spectrometer (TSQ Quantum Ultra, Thermo Electron Corporation) using atmospheric pressure chemical ionization in negative-ion mode and multiple reaction monitoring. The use of a surrogate internal standard in combination with HPLC-MS/MS provided a high degree of accuracy and precision. The extraction efficiency was greater than 70%. Repeated analyses of plasma and breast milk samples spiked with high (100 ng/ml), medium (50 ng/ml) and low (5 ng/ml) concentrations of the analytes gave relative standard deviations of less than 12%. The limits of detection were in the range of 0.5-0.9 ng/ml for both matrices. Published by Elsevier B.V.

  5. In vivo study on the neurotransmitters and their metabolites change in depressive disorder rat plasma by ultra high performance liquid chromatography coupled to tandem mass spectrometry.

    Science.gov (United States)

    Zhao, Longshan; Zheng, Shuning; Su, Guangyue; Lu, Xiumei; Yang, Jingyu; Xiong, Zhili; Wu, Chunfu

    2015-04-15

    A sensitive and versatile, ultra-high performance, liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method coupled to pre-column derivatization for the simultaneous determination of 5-hydroxytryptamine (5-HT), 5-hydroxyindoleacetic acid (5-HIAA), dopamine (DA), norepinephrine (NE), homovanillic acid (HVA), γ-aminobutyric acid (GABA) and glutamic acid (Glu) was developed and validated in rat plasma. The analytes were dansylated under strong alkaline conditions after protein precipitation extraction, which were analyzed on a BEH C18 column using a gradient elution. The lower limit of quantification (LLOQ) values for 5-HT, 5-HIAA, DA, NE, HVA, GABA and Glu were 1.00, 1.00, 0.991, 0.992, 1.02, 1000, and 5030 pmol/mL, respectively. Good linearity was obtained (r > 0.99) and the intra- and inter-day precisions of the method (relative standard deviation, RSD%) were lower than 12%. The method was novel, sensitive and specific which can provide an alternative method for the quantification of neurotransmitters and their metabolites in plasma samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. High-performance liquid chromatography assay for the determination of the HIV-protease inhibitor tipranavir in human plasma in combination with nine other antiretroviral medications.

    Science.gov (United States)

    Choi, Sun Ok; Rezk, Naser L; Kashuba, Angela D M

    2007-03-12

    An accurate, sensitive and simple reverse-phase (RP) high-performance liquid chromatography (HPLC) assay has been developed and validated for the simultaneous quantitative determination of tipranavir with nine other antiretroviral drugs in plasma. A liquid-liquid extraction of the drugs in tert-butylmethylether (TBME) from 200 microL of plasma is followed by a reversed phase gradient HPLC assay with UV detection at 210 nm. The standard curve for the drug was linear in the range of 80-80,000 ng/mL for tipranavir; 10-10,000 ng/mL for nevirapine, indinavir, efavirenz, and saquinavir; and 25-10,000 ng/mL for amprenavir, atazanavir, ritonavir, lopinavir, and nelfinavir. The regression coefficient (r(2)) was greater than 0.998 for all analytes. This method has been fully validated and shown to be specific, accurate and precise. Due to an excellent extraction procedure giving good recovery and a clean baseline, this method is simple, rapid, accurate and provides excellent resolution and peak shape for all analytes. Thus this method is very suitable for therapeutic drug monitoring.

  7. In-tube solid-phase microextraction with molecularly imprinted polymer to determine interferon alpha 2a in plasma sample by high performance liquid chromatography.

    Science.gov (United States)

    Rodrigues Chaves, Andréa; Costa Queiroz, Maria Eugênia

    2013-11-29

    A molecularly imprinted sol–gel polymer (MIP) based on protein (biopharmaceutical) template with a mild template removal condition using protease was synthetized and evaluated as stationary phase for in-tube solid phase microextraction (in-tube SPME) of the interferon alpha 2a from plasma samples,followed by high performance liquid chromatography analysis with fluorescence detection (HPLC-FD).The developed MIP exhibited high selectivity for the analyte in a complex matrix. The in-tube SPME variables such as draw/eject cycles, draw/eject volume, and desorption conditions were optimized to establish the equilibrium conditions in a short time. The MIP in-tube SPME/HPLC-FD method presented linear response over a dynamic range of 8–300 ng mL−1, with a correlation coefficient of 0.997. The inter-assay precision presented coefficient of variation lower than 9.2%, and accuracy values between 92% and 98%. The developed MIP performed as well as other selective interferon alpha 2a stationary phases (e.g.,immunosorbent and restricted access material), with the advantage that it is robust, easy to handle and cheap to synthesize, in a addition to requiring smaller sample volume (50 L). Based on the analytical validation results, the proposed method (MIP in-tube SPME/HPLC-FD) can be a useful tool to determine interferon alpha 2a in plasma samples from patients receiving therapeutic dosages.

  8. Rapid and sensitive determination of levofloxacin in microsamples of human plasma by high-performance liquid chromatography and its application in a pharmacokinetic study.

    Science.gov (United States)

    Aguilar-Carrasco, José Carlos; Hernández-Pineda, Jessica; Jiménez-Andrade, Juan Miguel; Flores-Murrieta, Francisco Javier; Carrasco-Portugal, Miriam Del Carmen; López-Canales, Jorge Skiold

    2015-03-01

    A rapid, sensitive and simple high-performance liquid chromatographic assay with ultraviolet detection was developed for the quantification of levofloxacin in microsamples (100 μL) of human plasma. The extraction procedure included a protein precipitation technique and a short chromatographic running time (4.5 min). Analyses were carried out on a Symmetry C18 column using a mixture of acetonitrile and 0.01 m potassium dihydrogen aqueous solution (pH 3.4; 14:86 v/v) as mobile phase. The method provided specificity and was linear (r ≥ 0.9992) over the concentration range 0.1-12 µg/mL. The average absolute recovery was 93.59%. The intra- and inter-day coefficients of variation were levofloxacin was stable in all evaluations. The usefulness of this method was demonstrated in a pharmacokinetic study of levofloxacin in healthy adult volunteers. The present method offers two main advantages: (a) the use of microsamples reduces the total volume of blood to be collected from patients; and (b) it provides a good cost-effectiveness ratio. It is concluded that the method is rapid, simple, sensitive, economical and suitable for the determination of levofloxacin in human plasma using a small volume of sample. Copyright © 2014 John Wiley & Sons, Ltd.

  9. Simultaneous determination of acyclovir, ganciclovir, and (R)-9-[4-hydroxy-2-(hydroxymethyl)butyl]guanine in human plasma using high-performance liquid chromatography

    Science.gov (United States)

    Weller, Dennis R.; Balfour, Henry H.; Vezina, Heather E.

    2017-01-01

    Acyclovir, ganciclovir and (R)-9-[4-hydroxy-2-(hydroxymethyl)butyl]guanine are active in vitro against the Epstein–Barr virus (EBV) but their in vivo anti-EBV activity is not well understood. We developed a novel, sensitive high-performance liquid chromatography assay with ultraviolet detection for measuring acyclovir, ganciclovir and (R)-9-[4-hydroxy-2-(hydroxymethyl)butyl]guanine in human plasma to identify quantitative relationships between in vitro anti-EBV activity and therapeutic response. Characteristics of the assay include a low plasma volume (200 μL), perchloric acid protein precipitation, use of penciclovir as the internal standard, run times less than 8 min and a 50 ng/mL lower limit of quantification. The within- and between-assay variability is 0.7–4.8 and 1.0–7.9%, respectively. Accuracy for all three drugs ranges from 89.5 to 106.4% for four quality controls (50, 100, 1000 and 10,000 ng/mL). This assay supports pharmacokinetic and pharmacodynamic studies of candidate anti-EBV drugs in children and adults with EBV infections. PMID:19358150

  10. A simple and rapid ultra-high-performance liquid chromatography-tandem mass spectrometry method to determine plasma biotin in hemodialysis patients.

    Science.gov (United States)

    Yagi, Shigeaki; Nishizawa, Manabu; Ando, Itiro; Oguma, Shiro; Sato, Emiko; Imai, Yutaka; Fujiwara, Masako

    2016-08-01

    A simple, rapid, and selective method for determination of plasma biotin was developed using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). After single-step protein precipitation with methanol, biotin and stable isotope-labeled biotin as an internal standard (IS) were chromatographed on a pentafluorophenyl stationary-phase column (2.1 × 100 mm, 2.7 μm) under isocratic conditions using 10 mm ammonium formate-acetonitrile (93:7, v/v) at a flow rate of 0.6 mL/min. The total chromatographic runtime was 5 min for each injection. Detection was performed in a positive electrospray ionization mode by monitoring selected ion transitions at m/z 245.1/227.0 and 249.1/231.0 for biotin and the IS, respectively. The calibration curve was linear in the range of 0.05-2 ng/mL using 300 μL of plasma. The intra- and inter-day precisions were all biotin concentrations in hemodialysis patients. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  11. High-performance liquid chromatography with time-programmed fluorescence detection for the quantification of Levofloxacin in human plasma and cerebrospinal fluid in adults with tuberculous meningitis.

    Science.gov (United States)

    Van Toi, Pham; Pouplin, Thomas; Tho, Nguyen Duc Khanh; Phuong, Pham Nguyen; Chau, Tran Thi Hong; Thuong Thuong, Nguyen Thuy; Heemskerk, Dorothee; Hien, Tran Tinh; Thwaites, Guy E

    2017-09-01

    An accurate and reliable high-performance liquid chromatography with time-programmed fluorescence detection was developed and validated to measure levofloxacin in human plasma and cerebrospinal fluid (CSF). After solid phase extraction process using Evolute® ABN 96 fixed well plate; levofloxacin and internal standard-enoxacin were separated using a mobile phase consisting of phosphate buffer 10mM with 0.025% triethylamine pH 3.0 - acetonitrile (88:12, v/v) on a Purosphere RP-8e column (5μm, 125×4.0mm) at a flow rate of 1.2mL/min at 35°C. The excitation/emission wavelengths were set to 269/400nm and 294/500nm, for enoxacin and levofloxacin, respectively. The method was linear over the concentration range of 0.02 to 20.0μg/mL with a limit of detection of 0.01μg/mL. The relative standard deviation of intra-assay and inter-assay precision for levofloxacin at four quality controls concentrations (0.02, 0.06, 3.0 and 15.0μg/mL) were less than 7% and the accuracies ranged from 96.75% to 101.9% in plasma, and from 93.00% to 98.67% in CSF. The validated method was successfully applied to quantify levofloxacin in a considerable quantity of plasma (826) and CSF (477) samples collected from 232 tuberculous meningitis patients, and the preliminary intensive pharmacokinetics analysis from 14 tuberculous meningitis patients in Vietnam is described in this paper. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  12. Determination of plasma concentrations of levofloxacin by high performance liquid chromatography for use at a multidrug-resistant tuberculosis hospital in Tanzania.

    Science.gov (United States)

    Ebers, Andrew; Stroup, Suzanne; Mpagama, Stellah; Kisonga, Riziki; Lekule, Isaack; Liu, Jie; Heysell, Scott

    2017-01-01

    Therapeutic drug monitoring may improve multidrug-resistant tuberculosis (MDR-TB) treatment outcomes. Levofloxacin demonstrates significant individual pharmacokinetic variability. Thus, we sought to develop and validate a high-performance liquid chromatography (HPLC) method with ultraviolet (UV) detection for levofloxacin in patients on MDR-TB treatment. The HPLC-UV method is based on a solid phase extraction (SPE) and a direct injection into the HPLC system. The limit of quantification was 0.25 μg/mL, and the assay was linear over the concentration range of 0.25-15 μg/mL (y = 0.5668x-0.0603, R2 = 0.9992) for the determination of levofloxacin in plasma. The HPLC-UV methodology achieved excellent accuracy and reproducibility along a clinically meaningful range. The intra-assay RSD% of low, medium, and high quality control samples (QC) were 1.93, 2.44, and 1.90, respectively, while the inter-assay RSD% were 3.74, 5.65, and 3.30, respectively. The mean recovery was 96.84%. This method was then utilized to measure levofloxacin concentrations from patients' plasma samples from a retrospective cohort of consecutive enrolled subjects treated for MDR-TB at the national TB hospital in Tanzania during 5/3/2013-8/31/2015. Plasma was collected at 2 hours after levofloxacin administration, the time of estimated peak concentration (eCmax) treatment. Forty-one MDR-TB patients had plasma available and 39 had traceable programmatic outcomes. Only 13 (32%) patients had any plasma concentration that reached the lower range of the expected literature derived Cmax with the median eCmax being 5.86 (3.33-9.08 μg/ml). Using Classification and Regression Tree analysis, an eCmax ≥7.55 μg/mL was identified as the threshold which best predicted cure. Analyzing this CART derived threshold on treatment outcome, the time to sputum culture conversion was 38.3 ± 22.7 days vs. 47.8 ± 26.5 days (p = 0.27) and a greater proportion were cured, in 10 out of 15 (66.7%) vs. 6 out of 18 (33.3%) (p

  13. Ultra-high performance liquid chromatographic determination of levofloxacin in human plasma and prostate tissue with use of experimental design optimization procedures.

    Science.gov (United States)

    Szerkus, O; Jacyna, J; Wiczling, P; Gibas, A; Sieczkowski, M; Siluk, D; Matuszewski, M; Kaliszan, R; Markuszewski, M J

    2016-09-01

    Fluoroquinolones are considered as gold standard for the prevention of bacterial infections after transrectal ultrasound guided prostate biopsy. However, recent studies reported that fluoroquinolone- resistant bacterial strains are responsible for gradually increasing number of infections after transrectal prostate biopsy. In daily clinical practice, antibacterial efficacy is evaluated only in vitro, by measuring the reaction of bacteria with an antimicrobial agent in culture media (i.e. calculation of minimal inhibitory concentration). Such approach, however, has no relation to the treated tissue characteristics and might be highly misleading. Thus, the objective of this study was to develop, with the use of Design of Experiments approach, a reliable, specific and sensitive ultra-high performance liquid chromatography- diode array detection method for the quantitative analysis of levofloxacin in plasma and prostate tissue samples obtained from patients undergoing prostate biopsy. Moreover, correlation study between concentrations observed in plasma samples vs prostatic tissue samples was performed, resulting in better understanding, evaluation and optimization of the fluoroquinolone-based antimicrobial prophylaxis during transrectal ultrasound guided prostate biopsy. Box-Behnken design was employed to optimize chromatographic conditions of the isocratic elution program in order to obtain desirable retention time, peak symmetry and resolution of levofloxacine and ciprofloxacine (internal standard) peaks. Fractional Factorial design 2(4-1) with four center points was used for screening of significant factors affecting levofloxacin extraction from the prostatic tissue. Due to the limited number of tissue samples the prostatic sample preparation procedure was further optimized using Central Composite design. Design of Experiments approach was also utilized for evaluation of parameter robustness. The method was found linear over the range of 0.030-10μg/mL for human

  14. Narrow band imaging (NBI during medical thoracoscopy: first impressions

    Directory of Open Access Journals (Sweden)

    Blum Torsten

    2009-08-01

    Full Text Available Abstract Background This is the first ever evaluation of narrow band imaging (NBI, an innovative endoscopic imaging procedure, for the visualisation of pleural processes. Methods The pleural cavity was examined in 26 patients with pleural effusions using both white light and narrow band imaging during thoracoscopy under local anaesthesia. Results In the great majority of the patients narrow band imaging depicted the blood vessels more clearly than white light, but failed to reveal any differences in number, shape or size. Only in a single case with pleura thickened by chronic inflammation and metastatic spread of lung cancer did narrow band imaging show vessels that were not detectable under white light. Conclusion It is not yet possible to assess to what extent the evidence provided by NBI is superior to that achieved with white light. Further studies are required, particularly in the early stages of pleural processes.

  15. Simultaneous determination of fluoxetine, citalopram, paroxetine, venlafaxine in plasma by high performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-MS/ESI).

    Science.gov (United States)

    Juan, He; Zhiling, Zhou; Huande, Li

    2005-06-05

    Fluoxetine, citalopram, paroxetine and venlafaxine have been widely used in the treatment of depression. However, no study has been conducted to determine the four drugs simultaneously by high performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-MS/ESI). To establish a new, rapid and sensitive HPLC-MS/ESI method for simultaneous determination and screening in human plasma of the four most commonly prescribed nontricyclic antidepressants: fluoxetine, citalopram, paroxetine and venlafaxine. The analytes in plasma were extracted by solid-phase-extraction column after samples had been alkalinized. The HPLC separation of the analytes was performed on a MACHEREY-NAGEL C(18) (250 mmx4.6 mm, 5 microm, Germany) column, using water (formic acid 0.6 per thousand, ammonium acetate: 30 mmol/l)-acetonitrile (35:65, v/v) as mobile phase, with a flow-rate of 0.85 ml/min. The compounds were ionized in the electrospray ionization (ESI) ion source of the mass spectrometer and were detected in the selected ion recording (SIR) mode. The calibration curves were linear in the 5.0-1000.0 ng/ml range for all compounds, all of them with coefficients of determination above 0.9900. The average extraction recoveries for all the four analytes were above 73.2%. The methodology recoveries were higher than 95.0%. The limits of detection (LODs) were 0.5, 0.3, 0.3 and 0.1 ng/ml for fluoxetine, citalopram, paroxetine and venlafaxine, respectively. The intra- and inter-day variation coefficients were less than 15.0%. The method is accurate, sensitive and simple for routine therapeutic drug monitoring (TDM) as well as toxicologic screening, and for the study of the pharmacokinetics and metabolism of the four drugs.

  16. Quantification of cyproheptadine in human plasma by high-performance liquid chromatography coupled to electrospray tandem mass spectrometry in a bioequivalence study.

    Science.gov (United States)

    Mendes, Gustavo Duarte; Arruda, André; Chen, Lu Shi; de Almeida Magalhães, José Cássio; Alkharfy, Khalid M; De Nucci, Gilberto

    2012-01-01

    A rapid, sensitive and specific method to quantify cyproheptadine in human plasma using amitriptyline as the internal standard (IS) is described. The analyte and the IS were extracted from plasma by liquid-liquid extraction using a diethyl-ether/dichloromethane (70/30; v/v) solvent. After removing and drying the organic phase, the extracts were reconstituted with a fixed volume of acetonitrile/water (50/50 v/v)+0.1% of acetic acid. The extracts were analyzed by high performance liquid chromatography coupled to electrospray tandem mass spectrometry (LC-MS/MS). Chromatography was performed isocratically using an Alltech Prevail C18 5 µm analytical column, (150 mm x 4.6 mm I.D.). The method had a chromatographic run time of 4 min and a linear calibration curve ranging from 0.05 to 10 ng/mL (r2 > 0.99). The limit of quantification was 0.05 ng/mL. This HPLC/MS/MS procedure was used to assess the bioequivalence of cyproheptadine in two cyproheptadine + cobamamide (4 mg + 1 mg) tablet formulations (Cobactin® [cyproheptadine + cobamamide] test formulation supplied from Zambon Laboratórios Farmacêuticos Ltda. and Cobavital® from Solvay Farma (standard reference formulation)). A single 4 mg + 1 mg [cyproheptadine + cobamamide] dose of each formulation was administered to healthy volunteers. The study was conducted using an open, randomized, two-period crossover design with a 1-week washout interval. Since the 90% CI for Cmax and AUCs ratios were all within the 80-125% bioequivalence limit proposed by the US Food and Drug Administration, it was concluded that the cyproheptadine test formulation (Cobactin®) is bioequivalent to the Cobavital® formulation for both the rate and the extent of absorption of cyproheptadine. Copyright © 2011 John Wiley & Sons, Ltd.

  17. High-performance liquid chromatography assay for the quantification of HIV protease inhibitors and non-nucleoside reverse transcriptase inhibitors in human plasma.

    Science.gov (United States)

    Rezk, Naser L; Tidwell, Richard R; Kashuba, Angela D M

    2004-06-15

    An accurate, sensitive, and specific reverse-phase high-performance liquid chromatography (HPLC) assay for the simultaneous quantitative determination of HIV-protease inhibitors (PIs) (indinavir, IDV; amprenavir, APV; saquinavir, SQV; nelfinavir, NFV; ritonavir, RTV; and lopinavir, LPV) and non-nucleoside reverse transcriptase inhibitors (NNRTIs) (nevirapine, NVP; delavirdine, DLV; and efavirenz, EFV) in human blood plasma is described. The method provides excellent resolution and peak shape for nine analytes through a linear gradient (36-86%) of 25% phosphate buffer (pH 4.5), 60% acetonitrile, 15% methanol, and 0.75 ml TFA, with a gradient mobile phase flow rate (0.9-1.1 ml) over 30 min run time. The optimized solid phase extraction (SPE) extraction method using (1.0 ml, 100mg BOND ELUT-C18 Varian) column provides a clean base line and high extraction efficiency using a 550 microl plasma sample. The method was validated over the range of 10-10,000 ng/ml for NVP, IDV, and SQV; 10-5000 ng/ml for EFV; 25-10000 ng/ml for APV; and 25-5000 ng/ml for DLV, NFV, RTV, and LPV. This method is accurate (average accuracies of three different concentrations ranged from 91 to 112%), and precise (within- and between-day precision measures ranged from 0.2 to 5.7% and 0.1 to 5.4%, respectively). This method is suitable for use in clinical pharmacokinetic studies as well as in therapeutic drug monitoring (TDM).

  18. The Measurement of Meloxicam and Meloxicam Metabolites in Rat Plasma Using a High-Performance Liquid Chromatography-Ultraviolet Spectrophotometry Method.

    Science.gov (United States)

    Miyamoto, Aoi; Aoyama, Takahiko; Matsumoto, Yoshiaki

    2017-02-01

    A high-performance liquid chromatography-ultraviolet spectrophotometry (HPLC-UV) method for the determination of meloxicam (MEL) and meloxicam metabolites (5'-hydroxy meloxicam (5-HMEL) and 5'-carboxy meloxicam (5-CMEL)) has been developed. After extraction of MEL, 5-HMEL, and 5-CMEL from rat plasma using Oasis HLB cartridges, the extracts were separated with a Luna C18 (2) 100 A column (5 µm, 4.6×150 mm, Phenomenex) using a mobile phase of 50 mM phosphate buffer (pH 2.15, solvent A) and acetonitrile (solvent B) at a flow rate of 0.8 mL/min in a linear gradient. The detection wavelength was 360 nm, and the internal standard (IS) was piroxicam. Each calibration curve was linear in the range of 40 to 1000 ng/mL (r2>0.999). The extraction rates of MEL, 5-HMEL, and 5-CMEL were greater than 86.9%. The intra- and inter-day accuracies were in the range of 95.0 to 119.0%, and the precision was 0.2 to 17.0%. To the best of our knowledge, this is the first report of the quantitative and qualitative measurement of meloxicam and each metabolite using an HPLC-UV method.

  19. Determination of Tributyltin in Seafood Based on Magnetic Molecularly Imprinted Polymers Coupled with High-Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Hua Yang

    2017-01-01

    Full Text Available In this study, Fe3O4 was adopted as a carrier for surface molecular imprinting with two-stage polymerization. First, the functional monomer (methacrylic acid, MAA was modified on the surface of Fe3O4, which was then polymerized with the template molecule (tributyltin, TBT, cross linking agent (ethylene glycol dimethacrylate, EGDMA, and porogen (acetonitrile, hereby successfully preparing Fe3O4@MIPs prone to specifically identify TBT. The physical properties of Fe3O4@MIPs were then characterized, and adsorption and selection capacities were also assessed. Compared with conventional imprinting polymers, this magnetic molecular imprinting polymer (MIP displayed significantly increased and more specific adsorption. Meanwhile, its pretreatment was simpler and faster due to magnetic separation characteristics. Using magnetic MIPs as adsorbents for enrichment and separation, detection limit, recovery rate, and linear range were 1.0 ng g−1, 79.74–95.72%, and 5 ng g−1~1000 ng g−1, respectively, for a number of seafood samples. High-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS was used to analyze Tegillarca granosa, mussels, large yellow croaker, and other specimens, with recovery rates of 79.74–95.72% and RSD of 1.3%–4.7%. Overall, this method has a shorter total analysis time, lower detection limit, and wider linear range and can be more effectively applied to determine MAA in seawater and seafood.

  20. Arsenic Species in Edible Seaweeds Using In Vitro Biomimetic Digestion Determined by High-Performance Liquid Chromatography Inductively Coupled Plasma Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Yan-Fang Zhao

    2014-01-01

    Full Text Available Arsenite [As (III], arsenate [As (V], methylarsonate (MMA, and dimethylarsinate (DMA in five edible seaweeds (the brown algae Laminaria japonica, red algae Porphyra yezoensis, brown algae Undaria pinnatifida, brown algae Hizikia fusiformis, and green algae Enteromorpha prolifera were analyzed using in vitro digestion method determined by high-performance liquid chromatography inductively coupled plasma mass spectrometry. The results showed that DMA was found in the water extracts of all samples; As (III were detected in L. japonica and U. pinnatifida and about 23.0 and 0.15 mg/kg of As (V were found in H. fusiformis and E. prolifera respectively. However, after the gastrointestinal digestion, As (V was not detected in any of the five seaweeds. About 0.19 and 1.47 mg/kg of As (III was detected in the gastric extracts of L. japonica and H. fusiformis, respectively, and about 0.31 and 0.10 mg/kg of As (III were extracted from the intestinal extracts of Porphyra yezoensis and U. pinnatifida, respectively. The present results successfully reveal the differences of As species and levels in the water and biomimetic extracts of five edible seaweeds. The risk assessment of the inorganic arsenic in the five edible seaweeds based on present data showed almost no hazards to human health.

  1. Dithizone-functionalized solid phase extraction-displacement elution-high performance liquid chromatography-inductively coupled plasma mass spectrometry for mercury speciation in water samples.

    Science.gov (United States)

    Yin, Yong-guang; Chen, Ming; Peng, Jin-feng; Liu, Jing-fu; Jiang, Gui-bin

    2010-06-15

    A novel and simple solid phase extraction (SPE)-high performance liquid chromatography (HPLC)-inductively coupled plasma mass spectrometry (ICP-MS) method was developed for determination of inorganic mercury (IHg), methylmercury MeHg and ethylmercury (EtHg) in water samples in the present work. The procedure involves pre-functionalization of the commercially available C18 SPE column with dithizone, loading water sample, displacement elution of mercury species by Na(2)S(2)O(3) solution, followed by HPLC-ICP-MS determination. Characterization and optimization of operation parameters of this new SPE procedure were discussed, including eluting reagent selection, concentration of eluting reagent, volume of eluting reagent, effect of NaCl and humic acid in sample matrix. At optimized conditions, the detection limits of mercury species for 100mL water sample were about 3ngL(-1) and the average recoveries were 93.7, 83.4, and 71.7% for MeHg, IHg and EtHg, respectively, by spiking 0.2microgL(-1) mercury species into de-ion water. Stability experiment reveals that both the dithizone-functionalized SPE cartridge and the mercury species incorporated were stable in the storage procedure. These results obtained demonstrate that SPE-HPLC-ICP-MS is a simple and sensitive technique for the determination of mercury species at trace level in water samples with high reproducibility and accuracy.

  2. Speciation and determination of bioavailable arsenic species in soil samples by one-step solvent extraction and high-performance liquid chromatography with inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Sun, Jing; Ma, Li; Yang, Zhaoguang; Lee, Hsiaowan; Wang, Lin

    2015-03-01

    A new analytical method was developed to determine the bioavailable arsenic species (arsenite, arsenate, monomethylarsonic acid, and dimethylarsonic acid) in soil samples using high-performance liquid chromatography with inductively coupled plasma mass spectrometry. Bioavailable arsenic was extracted with ammonium phosphate buffer by a simplified one-step solvent extraction procedure. To estimate the effect of variables on arsenic extraction, a two-level Plackett-Burman factorial design was conducted to screen the significant factors that were further investigated by a separate univariate approach. The optimum conditions were confirmed by compromising the stability of arsenic species and the extraction efficiency. The concentration of arsenic species was determined in method blank and soil-certified reference materials both spiked with standard solutions of arsenic species. All the target arsenic species were stable during the whole extraction procedure. Furthermore, the proposed method was applied to release bioavailable arsenic from contaminated soil samples, showing that the major arsenic species in soil samples were inorganic arsenic: arsenite and arsenate, of which the latter was dominant. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Simultaneous determination of amoxicillin and clavulanic acid in the human plasma by high performance liquid chromatography: Mass spectrometry (UPLC/MS

    Directory of Open Access Journals (Sweden)

    Ćirić Biljana

    2010-01-01

    Full Text Available Background/Aim. Quantitative analysis of amoxicillin and clavulanic acid in biological matrices requires sensitive and specific methods which allow determination of therapeutic concentration in μg/mL range. Analytical methods for determination of their concentrations in body fluids described in literature include high performance liquid chromatography coupled to UV detector (HPLC-UV and liquid chromatography-mass spectrometry (LC-MS. The aim of this study was to develop sensitive and specific ultra performance liquid chromatography/ mass spectrometry (UPLC/MS method which could be used for the spectral identification and quantification of the low concentrations of amoxicillin and clavulanic acid in the human plasma. Method. A sensitive and specific UPLC/MS method for amoxicillin and clavulanic acid determination was developed in this study. The samples were taken from the adult healthy volunteers receiving per os one tablet of amoxicillin (875 mg in combination with clavulanic acid (125 mg. Results. Plasma samples were pretreated by direct deproteinization with perchloric acid. Quantification limit of 0.01 μg/ml for both amoxicillin and clavulanic acid was achieved. The method was reproducible day by day (RSD < 7 %. Analytical recoveries for amoxicillin ranged from 98.82% to 100.9% (for concentrations of 1, 5 and 20 μg/mL, and recoveries for clavulanic acid were 99,89% to 100.1% (for concentrations of 1, 2 and 5 μg/mL. This assay was successfully applied to a pilot pharmacokinetic study in healthy volunteers after a single-oral administration of amoxicillin/ clavulanic combination. The determined plasma concentrations of both amoxicillin and clavulanic acid were in the range of the expected values upon the literature data for HPLC-UV and LC-MS methods. Conclusion. The described method provided a few advantages comparing with LC/MS-MS method. The method is faster using running time of 5 minute, has lower limit of quantification (LOQ and it

  4. Three-phase, liquid-phase microextraction combined with high performance liquid chromatography-fluorescence detection for the simultaneous determination of fluoxetine and norfluoxetine in human plasma.

    Science.gov (United States)

    de Freitas, Daniela Fernanda; Porto, Carlos Eduardo Dobrovolskin; Vieira, Elisabeth Pizzamiglio; de Siqueira, Maria Elisa Pereira Bastos

    2010-01-05

    A three-phase, liquid-phase microextraction using a hollow fibre (HF-LPME) combined with high performance liquid chromatography-fluorescence detection (HPLC-FL) was developed for the analysis of fluoxetine (FLX) and its active metabolite, norfluoxetine (NFLX), in human plasma. An HF-LPME system using a disposable 7-cm polypropylene porous hollow fibre, 5 mL of alkaline plasma solution (donor phase), n-hexyl ether (extraction solvent) and 20 mM hydrochloric acid (acceptor phase) was used in the extraction. The method was validated after optimisation of several parameters that influence LPME efficiency. A reverse-phase LiChrospher 60 RP-Select B column (125 mm x 4 mm, 5 microm particle size) was used with 0.005 M sodium acetate buffer (pH 4.5) and acetonitrile at a 50:50 (v/v) as the mobile phase at a flow rate of 0.6 mL min(-1). In these conditions satisfactory chromatographic resolution and efficiency for the analytes were obtained. Fluorescence detection at 230 nm excitation wavelength and 290 nm emission wavelength was performed. Linearity over a range of 5-500 ng mL(-1), with determination coefficients (R(2)) of 0.9999 and 0.9962 for FLX and NFLX, respectively, was established. Venlafaxine was used as the internal standard for both analytes. Extraction recoveries from plasma samples were 70.9% for FLX and 59.7% for NFLX. The intra-day coefficients of variation (CVs) were below 5.4%, and inter-day CVs were below 13.0%, for both analytes at concentrations of 20, 80 and 160 ng mL(-1). HF-LPME extraction followed by HPLC-FL detection for FLX and NFLX analyses demonstrated excellent sample clean-up and selectivity. This method was simple, cheap, and easy to perform, yielding substantial analytes enrichment. The method was applied to the analysis of samples from 12 patients under fluoxetine treatment and proved suitable for routine therapeutic drug monitoring for this antidepressant.

  5. Propylthiouracil quantification in human plasma by high-performance liquid chromatography coupled with electrospray tandem mass spectrometry: application in a bioequivalence study.

    Science.gov (United States)

    Mendes, Gustavo D; Bittencourt, Samara; Vespasiano, Celso Francisco Pimentel; Babadópulos, Tainah; Gagliano-Jucá, Thiago; Arruda, André Moreira Martins; Perissutti, Elisa; Frecentese, Francesco; De Nucci, Gilberto

    2014-10-15

    A rapid, sensitive and specific method for quantifying propylthiouracil in human plasma using methylthiouracil as the internal standard (IS) is described. The analyte and the IS were extracted from plasma by liquid-liquid extraction using an organic solvent (ethyl acetate). The extracts were analyzed by high performance liquid chromatography coupled with electrospray tandem mass spectrometry (HPLC-MS/MS) in negative mode (ES-). Chromatography was performed using a Phenomenex Gemini C18 5μm analytical column (4.6mm×150mm i.d.) and a mobile phase consisting of methanol/water/acetonitrile (40/40/20, v/v/v)+0.1% of formic acid. For propylthiouracil and I.S., the optimized parameters of the declustering potential, collision energy and collision exit potential were -60 (V), -26 (eV) and -5 (V), respectively. The method had a chromatographic run time of 2.5min and a linear calibration curve over the range 20-5000ng/mL. The limit of quantification was 20ng/mL. The stability tests indicated no significant degradation. This HPLC-MS/MS procedure was used to assess the bioequivalence of two propylthiouracil 100mg tablet formulations in healthy volunteers of both sexes in fasted and fed state. The geometric mean and 90% confidence interval CI of Test/Reference percent ratios were, without and with food, respectively: 109.28% (103.63-115.25%) and 115.60% (109.03-122.58%) for Cmax, 103.31% (100.74-105.96%) and 103.40% (101.03-105.84) for AUClast. This method offers advantages over those previously reported, in terms of both a simple liquid-liquid extraction without clean-up procedures, as well as a faster run time (2.5min). The LOQ of 20ng/mL is well suited for pharmacokinetic studies. The assay performance results indicate that the method is precise and accurate enough for the routine determination of the propylthiouracil in human plasma. The test formulation with and without food was bioequivalent to reference formulation. Food administration increased the Tmax and decreased

  6. High performance liquid chromatographic method for the determination of cetirizine and ambroxol in human plasma and urine--a boxcar approach.

    Science.gov (United States)

    Dharuman, J; Vasudhevan, M; Ajithlal, T

    2011-09-01

    A column switching high performance liquid chromatographic method with estimable sensitivity and accuracy was developed for the determination of cetirizine and ambroxol in human plasma using nebivolol as the internal standard. Plasma samples were prepared by liquid-liquid extraction in methylene chloride and a mixture of diethylether (80:20, v/v). The extracted samples were injected into a multifunctional clean-up column Supelcosil LCABZ (50 mm × 4.6 mm, 5 μm particle size) using mobile phase 1 comprising acetonitrile-phosphate buffer (pH 3.5; 20 mM) (20:80, v/v). The eluate of cetirizine and ambroxol were separated to an analytical Kromasil C(8) micro bore column (50 mm × 0.3 mm, 5 μm particle size) via a column switching device. A Kromasil C(18) analytical column (250 mm × 2.1 mm, 5 μm particle size) was used as a separation column. Mobile phase 2 consisting acetonitrile-triethylamine (0.5%) in phosphate buffer (pH 3.5; 20mM) (55:45, v/v) was used for the compound elution. The eluents were detected at 230 nm with photodiode array detector. An aliquot of 150 μl of plasma sample was introduced into the pretreatment column via the auto sampler using mobile phase 1 at a flow rate of 0.5 ml/min, column switching valve being positioned at A. The pretreatment column retained cetirizine, ambroxol and nebivolol (IS) in the column leaving the residual proteins of plasma eluted in void volume and drained out. The switching valve was shifted to position B at 7.5 min. Cetirizine, ambroxol and IS were eluted from the pretreatment column between 7. 5 and 11.5 min and introduced to the concentration column. Finally, cetirizine, ambroxol and IS were introduced to the separation column by switching valve using mobile phase 2 at a flow rate of 0.4 ml/min. During the analysis the pretreatment column was washed for the next analysis and resume to the position A. The total run time was 25 min for a sample. The procedure was repeated for urine analysis also. The method was

  7. Development and Validation of a High-Performance Liquid Chromatography Method With UV Detection for Determination of 1-(2-phenylethyl)-5- (quinaldin-4-yl) Biuret in Rat Plasma

    OpenAIRE

    Adibpour, Neda; Ahmadnasr, Maryam; Khodayar, Mohammad Javad; Rezaee, Saeed

    2013-01-01

    Background Recently, biuret derivatives have been reported as showing moderate to good cytotoxic effect against certain cancer cell lines. In this study, a high-performance liquid chromatography method was developed for determination of 1-(2-phenylethyl)-5-(quinaldin-4-yl) biuret (PEQB) in rat plasma to use in future studies on this compound and related derivatives. Objectives In this study, we describe a simple and sensitive high-performance liquid chromatography method with UV detection for...

  8. Simultaneous determination of protein-free and total positron emission tomography radioligand concentrations in plasma using high-performance frontal analysis followed by mixed micellar liquid chromatography: application to [11C]PBR28 in human plasma.

    Science.gov (United States)

    Nakao, Ryuji; Amini, Nahid; Halldin, Christer

    2013-09-17

    A two-dimensional liquid chromatographic (LC) system was developed for the determination of protein-free and total (free + bound forms) positron emission tomography (PET) radioligand concentrations in plasma by direct plasma injection. The unbound PET radioligand was first analyzed by high-performance frontal analysis using a short gel-filtration column and phosphate buffered saline solution as the mobile phase. All the collected effluent from the gel-filtration column was then transferred to the second dimension consisting of a monolithic C-18 column and mixed (anionic and nonionic surfactants) micellar eluent for determination of the total PET radioligand concentration. The simultaneous analysis of protein binding and radiometabolism of [(11)C]PBR28 was completed within 11 min without any pretreatment of plasma and employing a single analytical system. This system allowed highly sensitive analysis of total [(11)C]PBR28 with a limit of detection (LOD) of 1.6 becquerel (Bq). The LOD for the determination of unbound [(11)C]PBR28 was 21 Bq. Finally, simultaneous measurements of protein binding and radiometabolism of [(11)C]PBR28 in human plasma were achieved for up to 50 min after radioligand administration.

  9. Development and validation of a high-performance liquid chromatography-fluorescence detection method for the accurate quantification of colistin in human plasma.

    Science.gov (United States)

    Chepyala, Divyabharathi; Tsai, I-Lin; Sun, Hsin-Yun; Lin, Shu-Wen; Kuo, Ching-Hua

    2015-02-01

    Recently, colistin has become one of the most important drugs for treating infections caused by multidrug-resistant Gram-negative bacteria. Therapeutic drug monitoring is recommended to ensure the safety and efficacy of colistin and to improve clinical outcomes. This study developed an accurate and sensitive high-performance liquid chromatography-fluorescence detection (HPLC-FLD) method for the quantification of colistin in human plasma. The sample preparation included protein precipitation using trichloroacetic acid (TCA) and methanol, followed by in-solid phase extraction (In-SPE) derivatization with 9-fluorenylmethyl chloroformate (FMOC-Cl). A Poroshell 120 EC-C18 2.1×100mm (2.7μm) column was used in the HPLC method with a mobile phase composed of acetonitrile (ACN), tetrahydrofuran (THF), and deionized (DI) water (82%, 2%, 16% (v/v), respectively). Polymyxin B1 was used as the internal standard. The total analysis time was 22min under optimal separation conditions. The HPLC-FLD method was validated over a therapeutic range of 0.3-6.0μgmL(-1). The intra-day and inter-day precisions for colistin A and colistin B were below 9.9% and 4.5% relative standard deviations, respectively. The accuracy test results were between 100.2 and 118.4%. The extraction recoveries were between 81.6 and 94.1%. The method was linear over the test range, with a 0.9991 coefficient of determination. The limit of detection was 0.1μgmL(-1). The validated HPLC-FLD method was successfully applied to quantify the colistin concentrations in 2 patient samples for therapeutic drug monitoring. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Speciation of Selenium in Selenium-Enriched Sunflower Oil by High-Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry/Electrospray-Orbitrap Tandem Mass Spectrometry.

    Science.gov (United States)

    Bierla, Katarzyna; Flis-Borsuk, Anna; Suchocki, Piotr; Szpunar, Joanna; Lobinski, Ryszard

    2016-06-22

    The reaction of sunflower oil with selenite produces a complex mixture of selenitriglycerides with antioxidant and anticancer properties. To obtain insight into the identity and characteristics of the species formed, an analytical approach based on the combination of high-performance liquid chromatography (HPLC) with (78)Se-specific selenium detection by inductively coupled plasma mass spectrometry (ICP MS) and high-resolution (100 000), high mass accuracy (sunflower oil dissolved in isopropanol and methanol extract of the oil containing 65% selenium. HPLC-ICP MS showed 14 peaks, 11 of which could also be detected in the methanol extract. Isotopic patterns corresponding to molecules with one or two selenium atoms could be attributed by Orbitrap MS at the retention times corresponding to the HPLC-ICP MS peak apexes. Structural data for these species were acquired by MS(2) and MS(3) fragmentation of protonated or sodiated ions using high-energy collisional dissociation (HCD). A total of 11 selenium-containing triglycerol derivatives resulting from the oxidation of one or two double bonds of linoleic acid and analogous derivatives of glycerol-mixed linoleate(s)/oleinate(s) have been identified for the first time. The presence of these species was confirmed by the targeted analysis in the total oil isopropanol solution. Their identification corroborated the predicted elution order in reversed-phase chromatography: LLL (glycerol trilinoleate), LLO (glycerol dilinoleate-oleinate), LOO (glycerol linoleate-dioleinate), OOO (glycerol trioleinate), of which the extrapolation allowed for the prediction of the identity [glycerol dioleinate-stearate (OOS) and glycerol oleinate-distearate (OSS)] of the nonpolar species detected by ICP MS in the oil but not detected by electrospray MS.

  11. Simultaneous pressurized enzymatic hydrolysis extraction and clean up for arsenic speciation in seafood samples before high performance liquid chromatography-inductively coupled plasma-mass spectrometry determination.

    Science.gov (United States)

    Moreda-Piñeiro, Jorge; Alonso-Rodríguez, Elia; Moreda-Piñeiro, Antonio; Moscoso-Pérez, Carmen; Muniategui-Lorenzo, Soledad; López-Mahía, Purificación; Prada-Rodríguez, Darío; Bermejo-Barrera, Pilar

    2010-10-29

    The feasibility of pressurized conditions to assist enzymatic hydrolysis of seafood tissues for arsenic speciation was novelty studied. A simultaneous in situ (in cell) clean-up procedure was also optimized, which speeds up the whole sample treatment. Arsenic species (As(III), MMA, DMA, As(V), AsB and AsC) were released from dried seafood tissues using pepsin as a protease, and the arsenic species were separated/quantified by anion exchange high performance liquid chromatography (HPLC) coupled to inductively coupled plasma-mass spectrometry (ICP-MS). Variables inherent to the enzymatic activity (pH, temperature and ionic strength), the amount of enzyme (pepsin), and factors affecting pressurization (pressure, static time, number of cycles and amount of dispersing agent, C-18) were fully evaluated. Pressurized assisted enzymatic hydrolysis (PAEH) with pepsin can be finished after few minutes (two cycles of 2 min each one plus 3 min to reach the hydrolysis temperature of 50 °C). A total sample solubilisation is not achieved after the procedure, however it is efficient enough for breaking down certain bonds of bio-molecules and for releasing arsenic species. The developed method has been found to be precise (RSDs lower than 6% for As(III), DMA and As(V); and 3% for AsB) and sensitive (LOQs of 18.1, 36.2, 35.7, 28.6, 20.6 and 22.5 ng/g for As(III), MMA, DMA, As(V), AsB and AsC, respectively). The optimized methodology was successfully applied to different certified reference materials (DORM-2 and BCR 627) which offer certified AsB and DMA contents, and also to different seafood products (mollusks, white fishes and cold water fishes). Copyright © 2010 Elsevier B.V. All rights reserved.

  12. Composition of chemical species of selenium contained in selenium-enriched shiitake mushroom and vegetables determined by high performance liquid chromatography with inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Yoshida, Munehiro; Sugihara, Satoru; Inoue, Yuki; Chihara, Yûko; Kondô, Mariko; Miyamoto, Saori; Sukcharoen, Benjama

    2005-06-01

    Selenium (Se) species in Se-enriched shiitake mushroom (Lentinula edodes) were identified and quantified by high performance liquid chromatography with inductively coupled plasma mass spectrometry (HPLC-ICPMS). Two types of Se-enriched shiitake obtained from selenite- or selenate-fertilized mushroom beds were used. More than 80% of Se in both shiitake samples could not be extracted with 0.2 M HCl. Protease digestion released a large amount of selenomethionine from the shiitake enriched with selenite. However, most of the Se in the shiitake enriched with selenate was not released by protease but was released by a cell wall digestive enzyme and most of the Se released was identified as selenate. These results indicate that the main Se species in the shiitake enriched with selenite or selenate is selenomethionine bound to protein or selenate bound to polysaccharides in the cell wall, respectively. Several Se-enriched vegetables grown on a soil fertilized with selenate were also analyzed by HPLC-ICPMS. Four Se species, selenate, Se-methylselenocysteine, selenomethionine, gamma-glutamyl-Se-methylselenocysteine, and an unknown Se compound were detected in the vegetables. The composition of Se species varied with the kinds or parts of vegetables. The main Se species in bulbs, leaves or flowers of the Se-enriched garlic, onions, cabbage and ashitaba were selenate, Se-methylselenocysteine or gamma-glutamyl-Se-methylselenocysteine, while those in fruit bodies of the peppers and pumpkin were selenomethionine bound to protein. Bioavailabilities of Se in the shiitake mushroom enriched with selenite and the vegetables enriched with selenate are expected to be high, but that in shiitake enriched with selenate may be low.

  13. SAFARI 2000 NBI Vegetation Map of the Savannas of Southern Africa

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: The National Botanical Institute (NBI) has mapped woody plant species distribution to provide estimates of individual species contribution to peak leaf...

  14. Study of NBI-driven chirping mode properties and radial location by the heavy ion beam probe in the TJ-II stellarator

    Science.gov (United States)

    Melnikov, A. V.; Eliseev, L. G.; Castejón, F.; Hidalgo, C.; Khabanov, P. O.; Kozachek, A. S.; Krupnik, L. I.; Liniers, M.; Lysenko, S. E.; de Pablos, J. L.; Sharapov, S. E.; Ufimtsev, M. V.; Zenin, V. N.; HIBP Group; TJ-II Team

    2016-11-01

    Alfvén eigenmodes (AEs) were studied in low magnetic shear flexible heliac TJ-II (B 0  =  0.95 T, R 0  =  1.5 m,   =  0.22 m) neutral beam injection (NBI) heated plasmas (P NBI  ⩽  1.1 MW, E NBI  =  32 keV) using the heavy ion beam probe (HIBP). L-mode hydrogen plasmas heated with co-, counter- and balanced-NBI and electron cyclotron resonance heating (ECRH) were investigated in various magnetic configurations with rotational transform ι(a)/2π  =  1/q ~ 1.5-1.6. The HIBP diagnostic is capable of simultaneously measuring the oscillations of the plasma electric potential, density and poloidal magnetic field. In earlier studies chirping modes have been observed with 250 kHz  vacuum vessel. The absence of ECRH in the discharges studied here shows that ECRH is not a necessary ingredient to obtain chirping modes in TJ-II but rather a tool for obtaining low-density discharges. Using the HIBP we deduce that the location of the AE chirping mode is  -0.8  ballooning character, while the density and B pol perturbations are nearly symmetric for both ECRH  +  NBI and NBI-only plasmas. On TJ-II, the dominant effect on the nonlinear evolution of the AE from the chirping state to the steady-frequency state is the magnetic configuration, determined by the vacuum ι and plasma current I pl.

  15. Simultaneous quantitative determination of the HIV protease inhibitors amprenavir, indinavir, nelfinavir, ritonavir and saquinavir in human plasma by ion-pair high-performance liquid chromatography with ultraviolet detection

    NARCIS (Netherlands)

    van Heeswijk, R. P.; Hoetelmans, R. M.; Harms, R.; Meenhorst, P. L.; Mulder, J. W.; Lange, J. M.; Beijnen, J. H.

    1998-01-01

    A reversed-phase high-performance liquid chromatographic assay for the simultaneous quantitative determination of five HIV protease inhibitors (i.e. amprenavir, indinavir, nelfinavir, ritonavir, and saquinavir) in human plasma is described. Sample pretreatment consisted of solid-phase extraction

  16. Clinical experiences of NBI laryngoscope in diagnosis of laryngeal lesions

    Science.gov (United States)

    Qi, Xinmeng; Yu, Dan; Zhao, Xue; Jin, Chunshun; Sun, Changling; Liu, Xueshibojie; Cheng, Jinzhang; Zhang, Dejun

    2014-01-01

    Endoscopy is essential for the diagnosis and treatment of cancers derived from the larynx. However, a laryngoscope with conventional white light (CWL) has technical limitations in detecting small or superficial lesions on the mucosa. Narrow band imaging especially combined with magnifying endoscopy (ME) is useful for the detection of superficial squamous cell carcinoma (SCC) within the oropharynx, hypopharynx, and oral cavity. A total of 3675 patients who have come to the outpatient clinic and complained of inspiratory stridor, dyspnea, phonation problems or foreign body sensation, were enrolled in this study. We describe the glottic conditions of the patients. All 3675 patients underwent laryngoscopy equipped with conventional white light (CWL) and NBI system. 1149 patients received a biopsy process. And 1153 lesions were classified into different groups according to their histopathological results. Among all the 1149 patients, 346 patients (312 males, 34 females; mean age 62.2±10.5 years) were suspected of having a total of 347 precancerous or cancerous (T1 or T2 without lymphnode involvement) lesions of the larynx under the CWL. Thus, we expected to attain a complete vision of what laryngeal lesions look like under the NBI view of a laryngoscope. The aim was to develop a complete description list of each laryngeal conditions (e.g. polyps, papilloma, leukoplakia, etc.), which can serve as a criteria for further laryngoscopic examinations and diagnosis. PMID:25419362

  17. Experiments and simulations for the dynamics of cesium in negative hydrogen ion sources for ITER N-NBI

    Energy Technology Data Exchange (ETDEWEB)

    Gutser, Raphael

    2010-07-21

    The injection of fast neutral particles (NBI) into a fusion plasma is an important method for plasma heating and current drive. A source for negative deuterium ions delivering an 1 MeV beam that is accelerated to a specific energy and neutralized by a gas target is required for the ITER-NBI. Cesium seeding is required to extract high negative ion current densities from these sources. The optimization of the cesium homogeneity and control are major objectives to achieve the source requirements imposed by ITER. Within the scope of this thesis, the Monte Carlo based numerical transport simulation CsFlow3D was developed, which is the first computer model that is capable of simulating the flux and the accumulation of cesium on the surfaces of negative-ion sources. Basic studies that support the code development were performed at a dedicated experiment at the University of Augsburg. Input parameters of the ad- and desorption of cesium at ion source relevant conditions were taken from systematic measurements with a quartz micro balance, while the injection rate of the cesium oven at the ion source was determined by surface ionization detection. This experimental setup was used for further investigations of the work function of cesium-coated samples during plasma exposure. (orig.)

  18. Towards powerful negative ion beams at the test facility ELISE for the ITER and DEMO NBI systems

    Science.gov (United States)

    Fantz, U.; Hopf, C.; Wünderlich, D.; Friedl, R.; Fröschle, M.; Heinemann, B.; Kraus, W.; Kurutz, U.; Riedl, R.; Nocentini, R.; Schiesko, L.

    2017-11-01

    The test facility ELISE represents an important step in the European R&D roadmap towards the neutral beam injection (NBI) systems on ITER. ELISE provides early experience with operation of large radio frequency (RF) driven negative hydrogen ion sources. Starting with first plasma pulses in March 2013, ELISE has demonstrated stable 1 h plasma discharges with repetitive 10 s beam extraction pulses every 3 min in hydrogen and deuterium at the pressure of 0.3 Pa required by ITER. Stable ion currents of 9.3 A and 5.8 A have been extracted using only one quarter of the available RF power and reducing the extraction voltage in order to control the co-extracted electrons. The best hydrogen pulse for the required 1000 s for hydrogen gave an extracted current of 21.4 A and resulted in an accelerated current of 17.9 A, using only 53 kW per driver. Linear scaling towards full RF power (90 kW/driver) predicts that the target value of the negative ion current (H-: 33 A extracted, 23 A accelerated; D-: 28 A extracted and 20 A accelerated) can be achieved or even exceeded. Issues in long pulse operation are the caesium dynamics and the stability of the co-extracted electron current, for which the caesium management and the magnetic field configuration are promising tools for optimisation. Operation at high RF power for long pulses has highest priority for the next experimental campaign. In parallel or in a later stage, ELISE could serve as a test bed for studies on a DEMO NBI system. Examples are concepts concerning RF efficiency, operation with largely reduced caesium consumption or with caesium alternatives, and neutralization of the accelerated ion beam by a laser neutralizer in order to improve efficiency and reliability of NBI systems. Lab scale experiments on these topics are carried out presently in parallel with ELISE operation.

  19. Liquid-liquid extraction combined with high performance liquid chromatography-diode array-ultra-violet for simultaneous determination of antineoplastic drugs in plasma

    Directory of Open Access Journals (Sweden)

    Ananda Lima Sanson

    2011-06-01

    Full Text Available A liquid-liquid extraction (LLE combined with high-performance liquid chromatography-diode array detection method for simultaneous analysis of four chemically and structurally different antineoplastic drugs (cyclophosphamide, doxorubicin, 5-fluorouracil and ifosfamide was developed. The assay was performed by isocratic elution, with a C18 column (5 µm, 250 x 4.6 mm and mobile phase constituted by water pH 4.0- acetonitrile-methanol (68:19:13, v/v/v, which allowed satisfactory separation of the compounds of interest. LLE, with ethyl acetate, was used for sample clean-up with recoveries ranging from 60 to 98%. The linear ranges were from 0.5 to 100 µg mL-1, for doxorubicin and 1 to 100 µg mL-1, for the other compounds. The relative standard deviations ranged from 5.5 to 17.7%. This method is a fast and simple alternative that can be used, simultaneously, for the determination of the four drugs in plasma, with a range enabling quantification of the drugs in pharmacokinetics, bioequivalence and therapeutic drug-monitoring studies.Um método de extração líquido-líquido (ELL combinado com cromatografia líquida de alta eficiência-detector de arranjo de diodos foi desenvolvido para análise simultânea de quatro fármacos antineoplásicos quimicamente e estruturalmente diferentes (ciclofosfamida, doxorrubicina, fluoruracila e ifosfamida. O estudo foi realizado sob condições isocráticas, com coluna C18 (5µm, 250 x 4.6 mm e fase móvel constituída por água pH 4.0-acetonitrila-metanol (68:19:13, v/v/v, que permitiu separação satisfatória dos analitos de interesse. A ELL, com acetato de etila, foi utilizada para limpeza da amostra, com recuperação variando de 60 a 98%. As faixas foram lineares de 0,5 a 100 µg mL-1 para doxorrubicina e 1 a 100 µg mL-1 para os outros compostos. O desvio padrão relativo variou de 5,5 a 17,7%. Este método é uma alternativa rápida e simples que pode ser usado, simultaneamente, para a determinação dos

  20. Determination of 20 trace elements and arsenic species for a realgar-containing traditional Chinese medicine Niuhuang Jiedu tablets by direct inductively coupled plasma-mass spectrometry and high performance liquid chromatography-inductively coupled plasma-mass spectrometry.

    Science.gov (United States)

    Jin, Pengfei; Liang, Xiaoli; Xia, Lufeng; Jahouh, Farid; Wang, Rong; Kuang, Yongmei; Hu, Xin

    2016-01-01

    Niuhuang Jiedu tablet (NHJDT) is a realgar-containing traditional Chinese medicine. A direct inductively coupled plasma-mass spectrometry (ICP-MS) method for the simultaneous determination of 20 trace elements (Mg, K, Ca, Na, Fe, As, Zn, Sr, Ba, Cu, Mn, Ni, Pb, V, Cr, Se, Co, Mo, Cd, Hg) in NHJDT, as well as in water, gastric fluid and intestinal fluid was established. Meanwhile, a high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) method was developed for the determination of arsenite (As(III)), arsenate (As(V)), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and for the identification of arsenobetaine (AsB) and arsenocholine (AsC) in these extracts. Both methods were fully validated in the respect of linearity, sensitivity, precision, stability and accuracy. The reliability of the ICP-MS method was further evaluated using a certified standard reference material prepared from dried tomato leaves (NIST, SRM 1572a). The analysis showed that some manufacturers formulated lower amount of realgar than required in the Chinese Pharmacopoeia (ChP) in their preparations. In addition, almost same extraction profiles for total As and inorganic As were found in water and in gastrointestinal fluids, while higher extraction rates for other 19 elements were observed in gastrointestinal fluids. Our findings show that the toxicities of Hg, Cu, Cd and Pb in NHJDP are low, while the real As toxicity in NHJDT should be deeply investigated. Copyright © 2015 Elsevier GmbH. All rights reserved.

  1. Strong suppression of impurity accumulation in steady-state hydrogen discharges with high power NBI heating on LHD

    Science.gov (United States)

    Nakamura, Y.; Tamura, N.; Yoshinuma, M.; Suzuki, C.; Yoshimura, S.; Kobayashi, M.; Yokoyama, M.; Nunami, M.; Nakata, M.; Nagaoka, K.; Tanaka, K.; Peterson, B. J.; Ida, K.; Osakabe, M.; Morisaki, T.; the LHD Experiment Group

    2017-05-01

    Strong suppression of impurity accumulation is observed in long pulse hydrogen discharges with high power NBI (neutral beam injection) heating (P nbi  >  10 MW) on the large helical device (LHD), even in the impurity accumulation window where the intrinsic impurities such as Fe and C are always accumulated into the plasma core. Density scan experiments in these discharges demonstrate to vanish the window and a new operational regime without impurity accumulation is found in steady state hydrogen discharges. Impurity pinch decreases with increasing ion temperature gradient and carbon Mach number. The peaking of the measured carbon profiles shows strong anti-correlations with the Mach number and its radial gradient. An external torque has a big impact on impurity transport and strong co-current rotation leads to an extremely hollow carbon profile, so-called ‘impurity hole’ observed in high ion temperature modes. Impurity pinch in the plasmas with net zero torque input (balanced NBI injection) is also strongly reduced by increasing ion temperature gradient, which can drive turbulent modes. The combination effect of turbulence and toroidal rotation plays an important role in the impurity transport.

  2. The role of narrow-band imaging (NBI) endoscopy in optical biopsy of vocal cord leukoplakia.

    Science.gov (United States)

    Staníková, L; Šatanková, J; Kučová, H; Walderová, R; Zeleník, K; Komínek, Pavel

    2017-01-01

    The aim of this study was to investigate whether observing microvascular changes by narrow-band imaging (NBI) endoscopy in the area surrounding leukoplakia is sufficient for discriminating between benign and malignant patterns of vocal cord leukoplakia. A total of 282 patients were investigated using white-light high-definition TV laryngoscopy and NBI endoscopy from 6/2013 to 8/2015, and 63 patients with a primary case of laryngeal leukoplakia were enrolled. Patients were divided into two groups based on leukoplakia with surrounding malignant intraepithelial papillary capillary loops (group I; 26/63) and leukoplakia with a surrounding benign vascular network (group II; 37/63), both by NBI endoscopy. All 63 patients were evaluated by blinded histological examination, and results were compared with NBI optical biopsy. Carcinoma in situ or invasive squamous cell carcinoma was confirmed in 22/26 cases (84.6 %) in group I. Hyperkeratosis or low-grade dysplasia was confirmed histologically in 31/37 (83.8 %) and squamous cell carcinoma in 2/37 (5.4 %) cases in group II. Accordance of NBI endoscopy and histopathological features of vocal cord leukoplakia lesions was statistically significant (kappa index 0.77, p leukoplakias based on optic prehistological diagnosis. The close accordance between NBI features and histological results suggests that a negative NBI endoscopy may be an indication for long-term endoscopy follow-up without histological evaluation.

  3. Impacts of lost fast ions on the TJ-II Vacuum Vessel during NBI; Impactos de los iones rapidos en la Camara de Vacio del TJ-II durante NBI

    Energy Technology Data Exchange (ETDEWEB)

    Guasp, J.

    1995-07-01

    The possible deposition patterns, on the Vacuum Vessel, of lost fast ions during the balanced tangential NBI in TJ-II helical axis Stellarator are analysed theoretically, establishing the relation between those impact points, the plasma exit and birth positions and the magnetic configuration characteristics. It is shown that direct losses are the most important, mainly those produced by the beam injected with the same direction that the magnetic field, increasing with beam energy and plasma density but with impacts remaining fixed on well defined zones, a periodically distributed along the Hard Core cover plates, producing high loads at high densities. The remaining losses, except for the shine through ones that predominate at low density, are periodically distributed, with smooth maxima and produce very low loads. No overlapping between the different kind of losses or beams is observed. (Author) 6 refs.

  4. A validated ultra-high-performance liquid chromatography-tandem mass spectrometry method for the selective analysis of free and total folate in plasma and red blood cells.

    Science.gov (United States)

    Kiekens, Filip; Van Daele, Jeroen; Blancquaert, Dieter; Van Der Straeten, Dominique; Lambert, Willy E; Stove, Christophe P

    2015-06-12

    A stable isotope dilution LC-MS/MS method is the method of choice for the selective quantitative determination of several folate species in clinical samples. By implementing an integrated approach to determine both the plasma and red blood cell (RBC) folate status, the use of consumables and time remains limited. Starting from a single 300μl whole blood sample, the folate status in plasma and RBCs can be determined after separating plasma and RBCs and sequential washing of the latter with isotonic buffer, followed by reproducible lysis using an ammonium-based buffer. Acidification combines both liberation of protein bound folates and protein precipitation. Sample cleanup is performed using a 96-well reversed-phase solid-phase extraction procedure, similar for both plasma and RBC samples. Analyses are performed by UHPLC-MS/MS. Method validation was successfully performed based on EMA-guidelines and encompassed selectivity, carry-over, linearity, accuracy, precision, recovery, matrix effect and stability. Plasma and RBC folates could be quantified in the range of 1-150nmol/l and 5-1500nmol/l, respectively. This method allows for the determination of 6 folate monoglutamates in both plasma and RBCs. It can be used to determine short and long term folate status in both normal and severely deficient subjects in a single analytical sequence. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. High Performance Liquid Chromatography Method for the ...

    African Journals Online (AJOL)

    High Performance Liquid Chromatography Method for the Determination of Anethole in Rat Plasma. ... Journal Home > Vol 13, No 5 (2014) > ... Results: GC determination showed that anethole in the essential oil of star anise exhibited a ...

  6. Determination of levodopa in human plasma by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS: application to a bioequivalence study

    Directory of Open Access Journals (Sweden)

    Heliana F. Martins

    2013-01-01

    Full Text Available A sensitive, accurate and simple method using HPLC-MS/MS was developed and validated for levodopa quantitation in human plasma. Analysis was achieved on a pursuit® C18 analytical column (5 µm; 150 x 4.6 mm i.d. using a mobile phase (methanol and water , 90:10, v/v containing formic acid 0.5% v/v, after extracting the samples using a simple protein plasma precipitation with perchloric acid. The developed method was validated in accordance with ANVISA guidelines and was successfully applied to a bioequivalence study in 60 healthy volunteers demonstrating the feasibility and reliability of the proposed method.

  7. Speciation of four selenium compounds using high performance liquid chromatography with on-line detection by inductively coupled plasma mass spectrometry or flame atomic absorption spectrometry

    DEFF Research Database (Denmark)

    Pedersen, Gitte Alsing; Larsen, Erik Huusfeldt

    1997-01-01

    An analytical method for the speciation of selenomethionine, selenocystine, selenite and selenate by high performance liquid chromatography (HPLC) with atomic spectrometric detection is presented. An organic polymeric strong anion exchange column was used as the stationary phase in combination...... of 1300 W. The limit of detection achieved under these conditions was 1 mu g L-1 (100 mu L injections). The HPLC-ICP-MS system was used for selenium speciation of selenite and selenate in aqueous solutions during a BCR certification exercise and for selenium speciation in the certified reference material...

  8. High Performance Marine Vessels

    CERN Document Server

    Yun, Liang

    2012-01-01

    High Performance Marine Vessels (HPMVs) range from the Fast Ferries to the latest high speed Navy Craft, including competition power boats and hydroplanes, hydrofoils, hovercraft, catamarans and other multi-hull craft. High Performance Marine Vessels covers the main concepts of HPMVs and discusses historical background, design features, services that have been successful and not so successful, and some sample data of the range of HPMVs to date. Included is a comparison of all HPMVs craft and the differences between them and descriptions of performance (hydrodynamics and aerodynamics). Readers will find a comprehensive overview of the design, development and building of HPMVs. In summary, this book: Focuses on technology at the aero-marine interface Covers the full range of high performance marine vessel concepts Explains the historical development of various HPMVs Discusses ferries, racing and pleasure craft, as well as utility and military missions High Performance Marine Vessels is an ideal book for student...

  9. SAFARI 2000 NBI Vegetation Map of the Savannas of Southern Africa

    Data.gov (United States)

    National Aeronautics and Space Administration — The National Botanical Institute (NBI) has mapped woody plant species distribution to provide estimates of individual species contribution to peak leaf area index...

  10. An optimized analytical method of fluconazole in human plasma by high-performance liquid chromatography with ultraviolet detection and its application to a bioequivalence study.

    Science.gov (United States)

    Kim, Sung-Su; Im, Ho-Taek; Kang, Il-Mo; Lee, Hyun-Su; Lee, Heon-Woo; Cho, Sung-Hee; Kim, Jong-Bin; Lee, Kyung-Tae

    2007-06-01

    A sensitive and accurate HPLC-UV method for the quantification of fluconazole (FLA) level in human plasma has been developed. The sample was prepared by one-step liquid-liquid extraction (LLE) of FLA from plasma using dichloromethane. Phenacetin was used as the internal standard. The chromatographic retention times of FLA and phenacetin were 4.6 and 8.3 min, respectively. The lower limit of quantitation (LLOQ) was 0.05 microg/mL, and no interferences were detected in the chromatograms. The devised HPLC-UV method was validated by evaluating its intra- and inter-day precisions and accuracies in a linear concentration range between 0.05 and 10.00 microg/mL. The devised method was successfully applied to a bioequivalence studies involving the oral administration of a single 150 mg FLA tablet and 3 x 50 mg FLA capsules in healthy Korean male volunteers.

  11. Determination of retinol and retinyl esters in human plasma by high-performance liquid chromatography with automated column switching and ultraviolet detection.

    Science.gov (United States)

    Hartmann, S; Froescheis, O; Ringenbach, F; Wyss, R; Bucheli, F; Bischof, S; Bausch, J; Wiegand, U W

    2001-02-25

    A HPLC method with automated column switching and UV detection is described for the simultaneous determination of retinol and major retinyl esters (retinyl palmitate, retinyl stearate, retinyl oleate and retinyl linoleate) in human plasma. Plasma (0.2 ml) was deproteinized by adding ethanol (1.5 ml) containing the internal standard retinyl propionate. Following centrifugation the supernatant was directly injected onto the pre-column packed with LiChrospher 100 RP-18 using 1.2% ammonium acetate-acetic acid-ethanol (80:1:20, v/v) as mobile phase. The elution strength of the ethanol containing sample solution was reduced by on-line supply of 1% ammonium acetate-acetic acid-ethanol (100:2:4, v/v). The retained retinol and retinyl esters were then transferred to the analytical column (Superspher 100 RP-18, endcapped) in the backflush mode and chromatographed under isocratic conditions using acetonitrile-methanol-ethanol-2-propanol (1:1:1:1, v/v) as mobile phase. Compounds of interest were detected at 325 nm. The method was linear in the range 2.5-2000 ng/ml with a limit of quantification for retinol and retinyl esters of 2.5 ng/ml. Mean recoveries from plasma were 93.4-96.5% for retinol (range 100-1000 ng/ml) and 92.7-96.0% for retinyl palmitate (range 5-1000 ng/ml). Inter-assay precision was retinol and retinyl palmitate, respectively. The method was successfully applied to more than 2000 human plasma samples from clinical studies. Endogenous levels of retinol and retinyl esters determined in female volunteers were in good accordance with published data.

  12. Determination of several N-methyl-D-aspartate receptor blockers in plasma and brain by a selective high-performance liquid chromatographic method with column switching.

    Science.gov (United States)

    Wyss, R; Bucheli, F; Philipp, W

    1998-02-27

    A general procedure is presented for the determination of several N-methyl-D-aspartate (NMDA) receptor open-channel and subtype-selective blockers, which have been evaluated and developed as neuroprotective drugs for the treatment of brain stroke and trauma. The method involves deproteination of plasma with ethanol, or homogenization of brain samples in ethanol, dilution of the supernatant with ammonium acetate and direct injection into an HPLC column-switching system. Although the investigated NMDA receptor blockers are all tertiary amines, they have quite different structures. However, they are all concentrated on the first column (Purospher RP-18, 125 x 4 mm), whereas polar interfering compounds are washed out with 1% ammonium acetate-acetic acid-acetonitrile (100:1:5, v/v/v). Due to the special selectivity of the Purospher RP-18 material, the analytes and the internal standard are then selectively eluted with 25% acetonitrile (without any buffer in the mobile phase) and transferred to the analytical column (Superspher 60 RP-select B, 250 x 4 mm), where they are separated by gradient elution and detected by UV or fluorescence detection. The low degree of interference allowed the development of sensitive methods with quantification limits of 5 ng/ml for animal plasma (0.4 ml used), 0.5 ng/ml for human plasma (1 ml used) and 50 ng/g for brain tissue (200 mg used).

  13. Arsenic speciation in seafood samples with emphasis on minor constituents. An investigation by high performance liquid chromatography with inductively coupled plasma mass spectrometric detection

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Pritzl, G.; Hansen, S. H.

    1993-01-01

    Extracts of 11 samples of shrimp, crab, fish, fish liver, shellfish and lobster digestive gland (hepatopancreas), including five certified reference materials, were investigated for their contents of arsenic compounds (arsenic speciation). The cation-exchange high performance liquid chromatography...... (as arsenic atom) relative to the total arsenic extracted from the samples were: arsenobetaine 19-98%, arsenocholine and trimethylarsine oxide 0-0.6% and the trimethylarsonium ion 0-2.2%. Additionally, an unknown arsenic species (U1) was present at 3.1-18% in the shellfish and in the lobster digestive...... gland, and another unknown (U2) was present at 0.2-6.4% in all samples. The contents of arsenite and arsenate were 0-1.4%, dimethylarsinate 8.2-29% while monomethylarsonate was detected only in oyster at 0.3% of the total extracted arsenic. Finding tetramethylarsonium ion and arsenocholine in a variety...

  14. Determination of fluoxetine enantiomers in rat plasma by pre-column fluorescence derivatization and column-switching high-performance liquid chromatography.

    Science.gov (United States)

    Guo, Xingjie; Fukushima, Takeshi; Li, Famei; Imai, Kazuhiro

    2002-04-01

    A column-switching HPLC method employing both octadecylsilica (ODS) and chiral columns with fluorescence detection was developed for the determination of enantiomer of fluoxetine (FLX), an antidepressant drug, in rat plasma. Racemic FLX was derivatized with a fluorescent reagent, 4-(N-chloroformylmethyl-N-methyl)amino-7-nitro-2,1,3-benzoxadiazole (NBD-COCl) or 4-(N-chloroformylmethyl-N-methyl)amino-7-N,N-dimethylaminosulfonyl-2,1,3-benzoxadiazole (DBD-COCl) and the enantiomeric separation of the resultant derivatives was examined on an amylose-based chiral column (CHIRALPAK AD-RH) in the reversed-phase mode. The derivative with NBD-COCl (NBD-FLX) showed a sufficient separation factor (a) and resolution (Rs) compared with that with DBD-COCl. Thus, FLX was derivatized with NBD-COCl and the resultant NBD-FLX was first quantified on the ODS column and then introduced to the CHIRALPAK AD-RH column via a six-port switching valve to examine the enantiomeric ratio. The intra- and inter-day accuracy (97.6-112.7%) and precision (1.47-10.60%) were satisfactory in the range 10-1000 nM FLX and the limit of quantification was approximately 10 nM. The absolute recoveries of FLX with hexane from rat plasma were in the range 87.5-92.2% (n = 3). The method was applied to determine FLX enantiomers in the plasma of rats administered FLX orally, and it was shown that the R-isomer was eliminated faster than the S-isomer.

  15. Method development for the determination of 24S-hydroxycholesterol in human plasma without derivatization by high-performance liquid chromatography with tandem mass spectrometry in atmospheric pressure chemical ionization mode.

    Science.gov (United States)

    Sugimoto, Hiroshi; Kakehi, Masaaki; Satomi, Yoshinori; Kamiguchi, Hidenori; Jinno, Fumihiro

    2015-10-01

    We developed a highly sensitive and specific high-performance liquid chromatography with tandem mass spectrometry method with an atmospheric pressure chemical ionization interface to determine 24S-hydroxycholesterol, a major metabolite of cholesterol formed by cytochrome P450 family 46A1, in human plasma without any derivatization step. Phosphate buffered saline including 1% Tween 80 was used as the surrogate matrix for preparation of calibration curves and quality control samples. The saponification process to convert esterified 24S-hydroxycholesterol to free sterols was optimized, followed by liquid-liquid extraction using hexane. Chromatographic separation of 24S-hydroxycholesterol from other isobaric endogenous oxysterols was successfully achieved with gradient mobile phase comprised of 0.1% propionic acid and acetonitrile using L-column2 ODS (2 μm, 2.1 mm id × 150 mm). This assay was capable of determining 24S-hydroxycholesterol in human plasma (200 μL) ranging from 1 to 100 ng/mL with acceptable intra- and inter-day precision and accuracy. The potential risk of in vitro formation of 24S-hydroxycholesterol by oxidation from endogenous cholesterol in human plasma was found to be negligible. The stability of 24S-hydroxycholesterol in relevant solvents and human plasma was confirmed. This method was successfully applied to quantify the plasma concentrations of 24S-hydroxycholesterol in male and female volunteers. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Simultaneous determination of HIV protease inhibitors amprenavir, atazanavir, indinavir, lopinavir, nelfinavir, ritonavir and saquinavir in human plasma by high-performance liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Dickinson, Laura; Robinson, Lesley; Tjia, John; Khoo, Saye; Back, David

    2005-12-27

    We report a precise and accurate method for simultaneous quantification of protease inhibitors (PIs) amprenavir, atazanavir, indinavir, lopinavir, nelfinavir, ritonavir and saquinavir in plasma. An internal standard was added to samples prior to protein precipitation with acetonitrile followed by addition of ammonium formate buffer. Analysis was by HPLC-MS/MS. Calibration curves were validated over concentration ranges encompassing both subtherapeutic and potentially 'toxic' drug concentrations. Inter- and intra-assay variation were below 11% and PI recovery was above 87%. The bioanalytical method described is successfully applied to measure PI concentrations obtained from clinical pharmacokinetic studies and routine therapeutic drug monitoring (TDM).

  17. High Performance Liquid Chromatography Method for the ...

    African Journals Online (AJOL)

    chromatography (HPLC) technique with UV-VIS detection method was developed for the determination of the compound in rat ... Keywords: Anethole, High performance liguid chromatography, Star anise, Essential oil, Rat plasma,. Illicium verum Hook. .... solution of anethole. Plasma proteins were precipitated by adding 0.3.

  18. High performance homes

    DEFF Research Database (Denmark)

    Beim, Anne; Vibæk, Kasper Sánchez

    2014-01-01

    . Consideration of all these factors is a precondition for a truly integrated practice and as this chapter demonstrates, innovative project delivery methods founded on the manufacturing of prefabricated buildings contribute to the production of high performance homes that are cost effective to construct, energy......Can prefabrication contribute to the development of high performance homes? To answer this question, this chapter defines high performance in more broadly inclusive terms, acknowledging the technical, architectural, social and economic conditions under which energy consumption and production occur...... efficient to operate and valuable for building communities. Herein discussed are two successful examples of low energy prefabricated housing projects built in Copenhagen Denmark, which embraced both the constraints and possibilities offered by prefabrication....

  19. Bioanalytical Method Development and Validation of Memantine in Human Plasma by High Performance Liquid Chromatography with Tandem Mass Spectrometry: Application to Bioequivalence Study

    Directory of Open Access Journals (Sweden)

    Ravi Kumar Konda

    2012-01-01

    Full Text Available A simple, sensitive, and rapid HPLC-MS/MS method was developed and validated for quantitative estimation of memantine in human plasma. Chromatography was performed on Zorbax SB-C18 (4.6×75 mm, 3.5 μm column. Memantine (ME and internal standard Memantine-d6(MED6 were extracted by using liquid-liquid extraction and analyzed by LC-ESI-MS/MS using multiple-reaction monitoring (MRM mode. The assay exhibited a linear dynamic range of 50.00–50000.00 pg/ml for ME in human plasma. This method demonstrated an intra- and interday precision within the range of 2.1–3.7 and 1.4–7.8%, respectively. Further intra- and interday accuracy was within the range of 95.6–99.8 and 95.7–99.1% correspondingly. The mean recovery of ME and MED6 was 86.07±6.87 and 80.31±5.70%, respectively. The described method was successfully employed in bioequivalence study of ME in Indian male healthy human volunteers under fasting conditions.

  20. PEEK tube-based online solid-phase microextraction-high-performance liquid chromatography for the determination of yohimbine in rat plasma and its application in pharmacokinetics study.

    Science.gov (United States)

    Xiang, Xiaowei; Shang, Bing; Wang, Xiaozheng; Chen, Qinhua

    2017-04-01

    Yohimbine is a novel compound for the treatment of erectile dysfunction derived from natural products, and pharmacokinetic study is important for its further development as a new medicine. In this work, we developed a novel PEEK tube-based solid-phase microextraction (SPME)-HPLC method for analysis of yohimbine in plasma and further for pharmacokinetic study. Poly (AA-EGDMA) was synthesized inside a PEEK tube as the sorbent for microextraction of yohimbine, and parameters that could influence extraction efficiency were systematically investigated. Under optimum conditions, the PEEK tube-based SPME method exhibits excellent enrichment efficiency towards yohimbine. By using berberine as internal standard, an online SPME-HPLC method was developed for analysis of yohimbine in human plasma sample. The method has wide linear range (2-1000 ng/mL) with an R2 of 0.9962; the limit of detection was determined and was as low as 0.1 ng/mL using UV detection. Finally, a pharmacokinetic study of yohimbine was carried out by the online SPME-HPLC method and the results have been compared with those of reported methods. Copyright © 2016 John Wiley & Sons, Ltd.

  1. Determination of rivaroxaban in patient's plasma samples by anti-Xa chromogenic test associated to High Performance Liquid Chromatography tandem Mass Spectrometry (HPLC-MS/MS).

    Science.gov (United States)

    Derogis, Priscilla Bento Matos; Sanches, Livia Rentas; de Aranda, Valdir Fernandes; Colombini, Marjorie Paris; Mangueira, Cristóvão Luis Pitangueira; Katz, Marcelo; Faulhaber, Adriana Caschera Leme; Mendes, Claudio Ernesto Albers; Ferreira, Carlos Eduardo Dos Santos; França, Carolina Nunes; Guerra, João Carlos de Campos

    2017-01-01

    Rivaroxaban is an oral direct factor Xa inhibitor, therapeutically indicated in the treatment of thromboembolic diseases. As other new oral anticoagulants, routine monitoring of rivaroxaban is not necessary, but important in some clinical circumstances. In our study a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was validated to measure rivaroxaban plasmatic concentration. Our method used a simple sample preparation, protein precipitation, and a fast chromatographic run. It was developed a precise and accurate method, with a linear range from 2 to 500 ng/mL, and a lower limit of quantification of 4 pg on column. The new method was compared to a reference method (anti-factor Xa activity) and both presented a good correlation (r = 0.98, p HPLC-MS/MS without interferences. The chromogenic and HPLC-MS/MS methods were highly correlated and should be used as clinical tools for drug monitoring. The method was applied successfully in a group of 49 real-life patients, which allowed an accurate determination of rivaroxaban in peak and trough levels.

  2. Determination of rivaroxaban in patient’s plasma samples by anti-Xa chromogenic test associated to High Performance Liquid Chromatography tandem Mass Spectrometry (HPLC-MS/MS)

    Science.gov (United States)

    Derogis, Priscilla Bento Matos; Sanches, Livia Rentas; de Aranda, Valdir Fernandes; Colombini, Marjorie Paris; Mangueira, Cristóvão Luis Pitangueira; Katz, Marcelo; Faulhaber, Adriana Caschera Leme; Mendes, Claudio Ernesto Albers; Ferreira, Carlos Eduardo dos Santos; França, Carolina Nunes; Guerra, João Carlos de Campos

    2017-01-01

    Rivaroxaban is an oral direct factor Xa inhibitor, therapeutically indicated in the treatment of thromboembolic diseases. As other new oral anticoagulants, routine monitoring of rivaroxaban is not necessary, but important in some clinical circumstances. In our study a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was validated to measure rivaroxaban plasmatic concentration. Our method used a simple sample preparation, protein precipitation, and a fast chromatographic run. It was developed a precise and accurate method, with a linear range from 2 to 500 ng/mL, and a lower limit of quantification of 4 pg on column. The new method was compared to a reference method (anti-factor Xa activity) and both presented a good correlation (r = 0.98, p HPLC-MS/MS without interferences. The chromogenic and HPLC-MS/MS methods were highly correlated and should be used as clinical tools for drug monitoring. The method was applied successfully in a group of 49 real-life patients, which allowed an accurate determination of rivaroxaban in peak and trough levels. PMID:28170419

  3. Determination of vitamin B6 vitamers and pyridoxic acid in plasma: development and evaluation of a high-performance liquid chromatographic assay

    DEFF Research Database (Denmark)

    Bisp, Marianne R; Bor, Mustafa Vakur; Heinsvig, Else-Marie

    2002-01-01

    were eluted with a gradient of acetonitrile (0.5-15%) in a potassium phosphate buffer with 1-octanesulfonic acid and triethylamine, pH 2.16. The concentration of the vitamers was determined with fluorescence detector (328 nm excitation, 393 nm emission) after postcolumn derivatization with phosphate...... vitamers pyridoxal 5'-phosphate (PLP), pyridoxal (PL), pyridoxamine 5'-phosphate (PMP), pyridoxine (PN), and pyridoxamine (PM) and the degradation product 4-pyridoxic acid (4-PA). The separation was accomplished using a C18 (ODS) analytical column and an ion-pair reversed-phase chromatography. B6 vitamers...... buffer containing 1 g/L sodium bisulfite. The performance of the assay was evaluated by analyzing six plasma samples with interrelated concentration and two control samples (unspiked and vitamer spiked) over a 3-months period. The HPLC method was able to identify PLP, 4-PA, PM, PL, PN, and PMP from all...

  4. Determination of imatinib plasma levels in patients with chronic myeloid leukemia by high performance liquid chromatography-ultraviolet detection and liquid chromatography-tandem mass spectrometry: methods' comparison.

    Science.gov (United States)

    Awidi, Abdalla; Salem, Isam I; Najib, Naji; Mefleh, Razan; Tarawneh, Bothainah

    2010-06-01

    The aims of this study were to validate and compare HPLC and LCMSMS analytical methods and their applicability for the quantitation of imatinib in human plasma. A total of 50 patients with chronic myeloid leukemia (CML) in chronic phase (CP) receiving 400 mg/day imatinib were enrolled in the study. Drug levels were determined by HPLC-UV and LCMSMS. HPLC intra-day accuracy ranged from 100.51 to 103.19%. LCMSMS accuracy ranged from 89.72 to 106.29%. The correlation coefficient between both methods was r(2)=0.96. HPLC can be used for imatinib levels' determinations in patients accurately and precisely. Copyright 2009 Elsevier Ltd. All rights reserved.

  5. Danish High Performance Concretes

    DEFF Research Database (Denmark)

    Nielsen, M. P.; Christoffersen, J.; Frederiksen, J.

    1994-01-01

    In this paper the main results obtained in the research program High Performance Concretes in the 90's are presented. This program was financed by the Danish government and was carried out in cooperation between The Technical University of Denmark, several private companies, and Aalborg University...

  6. High performance systems

    Energy Technology Data Exchange (ETDEWEB)

    Vigil, M.B. [comp.

    1995-03-01

    This document provides a written compilation of the presentations and viewgraphs from the 1994 Conference on High Speed Computing given at the High Speed Computing Conference, {open_quotes}High Performance Systems,{close_quotes} held at Gleneden Beach, Oregon, on April 18 through 21, 1994.

  7. Quantitative determination of several toxicological important mycotoxins in pig plasma using multi-mycotoxin and analyte-specific high performance liquid chromatography-tandem mass spectrometric methods.

    Science.gov (United States)

    Devreese, Mathias; De Baere, Siegrid; De Backer, Patrick; Croubels, Siska

    2012-09-28

    A sensitive and reliable multi-mycotoxin method was developed for the identification and quantification of several toxicological important mycotoxins such as deoxynivalenol (DON), deepoxy-deoxynivalenol (DOM-1), T-2 toxin (T-2), HT-2 toxin (HT-2), zearalenone (ZON), zearalanone (ZAN), α-zearalenol (α-ZOL), β-zearalenol (β-ZOL), α-zearalanol (α-ZAL), β-zearalanol (β-ZAL), ochratoxin A (OTA), fumonisin B1 (FB1) and aflatoxin B1 (AFB1) in pig plasma using liquid chromatography combined with heated electrospray ionization triple quadrupole tandem mass spectrometry (LC-h-ESI-MS/MS). Sample clean-up consisted of a deproteinization step using acetonitrile, followed by evaporation of the supernatant and resuspension of the dry residue in water/methanol (85/15, v/v). Each plasma sample was analyzed twice, i.e. once in the ESI+ and ESI- mode, respectively. This method can be used for the assessment of animal exposure to mycotoxins and in the diagnosis of mycotoxicoses. For the performance of toxicokinetic studies with individual mycotoxins, highly sensitive analyte-specific LC-MS/MS methods were developed. The multi-mycotoxin and analyte-specific methods were in-house validated: matrix-matched calibration graphs were prepared for all compounds and correlation and goodness-of-fit coefficients ranged between 0.9974-0.9999 and 2.4-15.5%, respectively. The within- and between-run precision and accuracy were evaluated and the results fell within the ranges specified. The limits of quantification for the multi-mycotoxin and analyte-specific methods ranged from 2 to 10 ng/mL and 0.5 to 5 ng/mL, respectively, whereas limits of detection fell between 0.01-0.52 ng/mL and <0.01-0.15 ng/mL, respectively. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Speciation of the bio-available iodine and bromine forms in edible seaweed by high performance liquid chromatography hyphenated with inductively coupled plasma-mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Romaris-Hortas, Vanessa; Bermejo-Barrera, Pilar [Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Chemistry, University of Santiago de Compostela, Avenida das Ciencias, s/n. 15782 - Santiago de Compostela (Spain); Moreda-Pineiro, Jorge [Department of Analytical Chemistry, Faculty of Sciences, University of A Coruna, Campus da Zapateira, s/n. 15071, A Coruna (Spain); Moreda-Pineiro, Antonio, E-mail: antonio.moreda@usc.es [Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Chemistry, University of Santiago de Compostela, Avenida das Ciencias, s/n. 15782 - Santiago de Compostela (Spain)

    2012-10-01

    Highlights: Black-Right-Pointing-Pointer Bioavailable iodine and bromine speciation in edible seaweed were developed. Black-Right-Pointing-Pointer In vitro dialyzability was used to assess the bioavailable fractions. Black-Right-Pointing-Pointer AEC hyphenated with inductively coupled plasma-mass spectrometry was used. Black-Right-Pointing-Pointer Iodide, MIT, DIT, bromide and bromate were found in dialyzates from edible seaweed. Black-Right-Pointing-Pointer Positive correlation between bioavailability and protein contents was found. - Abstract: A bioavailability study based on an in vitro dialyzability approach has been applied to assess the bio-available fractions of iodine and bromine species from edible seaweed. Iodide, iodate, 3-iodo-tyrosine (MIT), 3,5-diiodo-tyrosine (DIT), bromide and bromate were separated by anion exchange chromatography under a gradient elution mode (175 mM ammonium nitrate plus 15% (v/v) methanol, pH 3.8, as a mobile phase, and flow rates within the 0.5-1.5 mL min{sup -1} range). Inductively coupled plasma-mass spectrometry (ICP-MS) was used as a selective detector for iodine ({sup 127}I) and bromine ({sup 79}Br). Low dialyzability ratios (within the 2.0-18% range) were found for iodine species; whereas, moderate dialyzability percentages (from 9.0 to 40%) were obtained for bromine species. Iodide and bromide were the major species found in the dialyzates from seaweed, although MIT and bromate were also found in the dialyzates from most of the seaweed samples analysed. However, DIT was only found in dialyzates from Wakame, Kombu, and NIES 09 (Sargasso) certified reference material; whereas, iodate was not found in any dialyzate. Iodine dialyzability was found to be dependent on the protein content (negative correlation), and on the carbohydrate and dietary fibre levels (positive correlation). However, bromine dialyzability was only dependent on the protein amount in seaweed (negative correlation).

  9. Ultra high performance liquid chromatography-quadrupole-time of flight analysis for the identification and the determination of resveratrol and its metabolites in mouse plasma

    Energy Technology Data Exchange (ETDEWEB)

    Menet, M.C., E-mail: marie-claude.menet@parisdescartes.fr [Universite Paris Descartes, Sorbonne Paris cite, EA 4463, Faculte des Sciences Pharmaceutiques et Biologiques, 4 avenue de l' Observatoire, Paris 75270 (France); Cottart, C.H. [APHP, Groupe hospitalier Pitie-Salpetriere, Charles Foix, Service de Biochimie, 7 avenue de la Republique, Ivry sur Seine 94205 (France); Universite Paris Descartes, Sorbonne Paris cite, EA 4466, Faculte des Sciences Pharmaceutiques et Biologiques, 4 avenue de l' Observatoire, Paris 75270 (France); Taghi, M. [Universite Paris Descartes, Sorbonne Paris cite, EA 4463, Faculte des Sciences Pharmaceutiques et Biologiques, 4 avenue de l' Observatoire, Paris 75270 (France); Nivet-Antoine, V. [Universite Paris Descartes, Sorbonne Paris cite, EA 4466, Faculte des Sciences Pharmaceutiques et Biologiques, 4 avenue de l' Observatoire, Paris 75270 (France); APHP, Hopital Europeen Georges Pompidou, Service de Biochimie, 20 rue Leblanc, Paris 75015 (France); Dargere, D. [Universite Paris Descartes, Sorbonne Paris cite, EA 4463, Faculte des Sciences Pharmaceutiques et Biologiques, 4 avenue de l' Observatoire, Paris 75270 (France); and others

    2013-01-25

    Graphical abstract: Simultaneous identification and determination of new resveratrol metabolites in mice by UHPLC-Q-TOF in full scan mode. Highlights: Black-Right-Pointing-Pointer Fast method to quantify resveratrol and its main metabolites in the mouse plasma. Black-Right-Pointing-Pointer Isotope-labeled standards to build a linear calibration curve. Black-Right-Pointing-Pointer Linear calibration curve on a wide range of concentrations. Black-Right-Pointing-Pointer Simultaneous identification and quantification of metabolites by using full scan mode. Black-Right-Pointing-Pointer Detection of uncommon metabolites not yet described in mice. - Abstract: Resveratrol is a polyphenol that has numerous interesting biological properties, but, per os, it is quickly metabolized. Some of its metabolites are more concentrated than resveratrol, may have greater biological activities, and may act as a kind of store for resveratrol. Thus, to understand the biological impact of resveratrol on a physiological system, it is crucial to simultaneously analyze resveratrol and its metabolites in plasma. This study presents an analytical method based on UHPLC-Q-TOF mass spectrometry for the quantification of resveratrol and of its most common hydrophilic metabolites. The use of {sup 13}C- and D-labeled standards specific to each molecule led to a linear calibration curve on a larger concentration range than described previously. The use of high resolution mass spectrometry in the full scan mode enabled simultaneous identification and quantification of some hydrophilic metabolites not previously described in mice. In addition, UHPLC separation, allowing run times lower than 10 min, can be used in studies that requiring analysis of many samples.

  10. Development and validation of a high performance liquid chromatography quantification method of levo-tetrahydropalmatine and its metabolites in plasma and brain tissues: application to a pharmacokinetic study.

    Science.gov (United States)

    Abdallah, Inas A; Huang, Peng; Liu, Jing; Lee, David Y; Liu-Chen, Lee-Yuan; Hassan, Hazem E

    2017-04-01

    Levo-tetrahydropalmatine (l-THP) is an alkaloid isolated from Chinese medicinal herbs of the Corydalis and Stephania genera. It has been used in China for more than 40 years mainly as an analgesic with sedative/hypnotic effects. Despite its extensive use, its metabolism has not been quantitatively studied, nor there a sensitive reliable bioanalytical method for its quantification simultaneously with its metabolites. As such, the objective of this study was to develop and validate a sensitive and selective HPLC method for simultaneous quantification of l-THP and its desmethyl metabolites l-corydalmine (l-CD) and l-corypalmine (l-CP) in rat plasma and brain tissues. Rat plasma and brain samples were processed by liquid-liquid extraction using ethyl acetate. Chromatographic separation was achieved on a reversed-phase Symmetry® C18 column (4.6 × 150 mm, 5 μm) at 25°C. The mobile phase consisted of acetonitrile-methanol-10 mm ammonium phosphate (pH 3) (10:30:60, v/v) and was used at a flow rate of 0.8 mL/min. The column eluent was monitored at excitation and emission wavelengths of 230 and 315 nm, respectively. The calibration curves were linear over the concentration range of 1-10,000 ng/mL. The intra- and interday reproducibility studies demonstrated accuracy and precision within the acceptance criteria of bioanalytical guidelines. The validated HPLC method was successfully applied to analyze samples from a pharmacokinetic study of l-THP in rats. Taken together, the developed method can be applied for bioanalysis of l-THP and its metabolites in rodents and potentially can be transferred for bioanalysis of human samples. Copyright © 2016 John Wiley & Sons, Ltd.

  11. Identification and quantification of glucosamine in rabbit cartilage and correlation with plasma levels by high performance liquid chromatography-electrospray ionization-tandem mass spectrometry.

    Science.gov (United States)

    Pastorini, Elisabetta; Vecchiotti, Stefania; Colliva, Carolina; Persiani, Stefano; Rotini, Roberto; Roatti, Giulia; Zaccarelli, Lorenzo; Rovati, Lucio Claudio; Roda, Aldo

    2011-06-10

    A new HPLC-ESI-MS/MS method for the determination of glucosamine (2-amino-2-deoxy-d-glucose) in rabbit cartilage was developed and optimized. Glucosamine was extracted from cartilage by cryogenic grinding followed by protein precipitation with trichloroacetic acid. The HPLC separation was achieved with a polymer-based amino column using a mobile phase composed of 10mM ammonium acetate (pH 7.5)-acetonitrile (20:80%, v/v) at 0.3 mL min flow rate. d-[1-(13)C]Glucosamine was used as internal standard. Selective detection was performed by tandem mass spectrometry with electrospray source, operating in positive ionization mode and in multiple reaction monitoring acquisition (m/z 180→72 and 181→73 for glucosamine and internal standard, respectively). Limit of quantification was 0.045 ng injected, corresponding to 0.25 μg g⁻¹ in cartilage. Linearity was obtained up to 20 μg g⁻¹ (R(2)>0.991). Precision values (%R.S.D.) were <10%. Accuracy (% bias) ranged from -6.0% to 12%. Mean recoveries obtained at 3 concentration levels were higher than 81% (%R.S.D.≤8%). The method was applied to measure glucosamine levels in rabbit cartilage and plasma after single oral administration of glucosamine sulfate at a dose of 98 mg kg⁻¹(n=6). Glucosamine was present in cartilage in physiological condition before the treatment. After dosing, mean concentration of cartilage glucosamine significantly increased from 461 to 1040 ng g⁻¹. Cartilage glucosamine levels resulted to be well correlated with plasma concentrations, which therefore are useful to predict the target cartilage concentration and its pharmacological activity. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Simultaneous determination of seven anthraquinones in rat plasma by Ultra High Performance Liquid Chromatography-tandem Mass Spectrometry and pharmacokinetic study after oral administration of Semen Cassiae extract.

    Science.gov (United States)

    Yang, Chunjuan; Wang, Shuhong; Guo, Xiaowei; Sun, Jiahui; Liu, Lu; Wu, Lijun

    2015-07-01

    Semen Cassiae, called Juemingzi in China, is the seed of the annual Cassia obtusifolia L., of the leguminosae family. It has been used as healthy drinks to alleviate constipation and improve eyesight for many years in China. A simple sensitive UHPLC-MS/MS method has been developed and validated for the simultaneous determination and pharmacokinetic study of chrysophanol, emodin, aloe-emodin, rhein, physcion, obtusifolin and aurantio-obtusin in rat plasma. Chromatographic separation was accomplished on a C18 column with a 5min gradient elution. A tandem mass spectrometric detection was conducted using multiple reaction monitoring (MRM) via an electrospray ionization (ESI) source and operating in the negative ionization mode. The samples were prepared by LLE with ethyl acetate after being spiked with an internal standard (butylparaben). The current UHPLC-MS/MS assay was validated for linearity, intra-day and inter-day precisions, accuracy, extraction recovery and stability. The method was linear for all analytes over investigated range with all correlation coefficients greater than 0.9900. The lower limit of quantification (LLOQ) of each analyte was lower than 5ng/mL. Intra-day and inter-day precisions were less than 14.99%. The relative errors of accuracies were in the range of -14.60% to 5.11%. The mean recoveries and matrix effects of anthraquinones were higher than 65.54% and 93.26%, respectively. After oral administration 1.25g/kg of Semen Cassiae extract, the maximum plasma concentration (Cmax) was 1189.25±333.40ng/mL for chrysophanol, 38.48±3.15ng/mL for emodin, 79.20±34.76ng/mL for aloe-emodin, 152.70±23.91ng/mL for rhein, 461.85±266.77ng/mL for physcion, 243.59±22.71ng/mL for obtusifolin and 1950.44±638.86ng/mL for aurantio-obtusin, respectively. The time to reach the maximum plasma concentration (Tmax) was 0.333±0.071h for chrysophanol, 0.333±0.059h for emodin, 0.333±0.009h for aloe-emodin, 0.333±0.09h for rhein, 0.167±0.002h for physcion, 0.5

  13. Therapeutic drug monitoring of levetiracetam by high-performance liquid chromatography with photodiode array ultraviolet detection: preliminary observations on correlation between plasma concentration and clinical response in patients with refractory epilepsy.

    Science.gov (United States)

    Lancelin, Frédérique; Franchon, Emilie; Kraoul, Linda; Garciau, Isabelle; Brovedani, Sophie; Tabaouti, Khalid; Landré, Elisabeth; Chassoux, Francine; Paubel, Pascal; Piketty, Marie-Liesse

    2007-10-01

    Levetiracetam is a new antiepileptic drug prescribed for the treatment of patients with refractory partial seizures with or without secondary generalization as well as for the treatment of juvenile myoclonic epilepsy. A rapid and specific method by high-performance liquid chromatography diode array detection was developed to measure the concentration of levetiracetam in human plasma. The trough plasma concentrations measured in 69 epileptic patients treated with 500 to 3000 mg/d of levetiracetam ranged from 1.1 to 33.5 microg/mL. The mean (range) levetiracetam plasma concentrations in responders and nonresponders were 12.9 microg/mL (4.6-21 microg/mL) and 9.5 microg/mL (1.1-20.9 microg/mL), respectively. A wide variability in concentration-response relationships was observed in patients. Using a receiver operating characteristic curve, the threshold levetiracetam concentration for a therapeutic response was 11 microg/mL. The sensitivity and specificity for this threshold levetiracetam concentration were 73% and 71%, respectively. According to chi analysis, this finding was not significant probably because of the small number of patients and because of their refractory seizure type. Nevertheless, the levetiracetam plasma concentration could be used to help clinicians detect severe intoxication or to verify compliance by repeating the measurement in patients.

  14. Low temperature plasma synthesis of mesoporous Fe3O4 nanorods grafted on reduced graphene oxide for high performance lithium storage.

    Science.gov (United States)

    Zhou, Quan; Zhao, Zongbin; Wang, Zhiyu; Dong, Yanfeng; Wang, Xuzhen; Gogotsi, Yury; Qiu, Jieshan

    2014-02-21

    Transition metal oxide coupling with carbon is an effective method for improving electrical conductivity of battery electrodes and avoiding the degradation of their lithium storage capability due to large volume expansion/contraction and severe particle aggregation during the lithium insertion and desertion process. In our present work, we develop an effective approach to fabricate the nanocomposites of porous rod-shaped Fe3O4 anchored on reduced graphene oxide (Fe3O4/rGO) by controlling the in situ nucleation and growth of β-FeOOH onto the graphene oxide (β-FeOOH/GO) and followed by dielectric barrier discharge (DBD) hydrogen plasma treatment. Such well-designed hierarchical nanostructures are beneficial for maximum utilization of electrochemically active matter in lithium ion batteries and display superior Li uptake with high reversible capacity, good rate capability, and excellent stability, maintaining 890 mA h g(-1) capacity over 100 cycles at a current density of 500 mA g(-1).

  15. High-Performance Networking

    CERN Document Server

    CERN. Geneva

    2003-01-01

    The series will start with an historical introduction about what people saw as high performance message communication in their time and how that developed to the now to day known "standard computer network communication". It will be followed by a far more technical part that uses the High Performance Computer Network standards of the 90's, with 1 Gbit/sec systems as introduction for an in depth explanation of the three new 10 Gbit/s network and interconnect technology standards that exist already or emerge. If necessary for a good understanding some sidesteps will be included to explain important protocols as well as some necessary details of concerned Wide Area Network (WAN) standards details including some basics of wavelength multiplexing (DWDM). Some remarks will be made concerning the rapid expanding applications of networked storage.

  16. High Performance Concrete

    Directory of Open Access Journals (Sweden)

    Traian Oneţ

    2009-01-01

    Full Text Available The paper presents the last studies and researches accomplished in Cluj-Napoca related to high performance concrete, high strength concrete and self compacting concrete. The purpose of this paper is to raid upon the advantages and inconveniences when a particular concrete type is used. Two concrete recipes are presented, namely for the concrete used in rigid pavement for roads and another one for self-compacting concrete.

  17. Development of anion-exchange/reversed-phase high performance liquid chromatography-inductively coupled plasma-mass spectrometry methods for the speciation of bio-available iodine and bromine from edible seaweed.

    Science.gov (United States)

    Romarís-Hortas, Vanessa; Bermejo-Barrera, Pilar; Moreda-Piñeiro, Antonio

    2012-05-04

    Anion exchange high performance liquid chromatography hyphenated with inductively coupled plasma-mass spectrometry has been novelly applied to assess inorganic (iodide and iodate) and organic (3-iodotyrosine - MIT, and 3,5-diiodotyrosine - DIT) iodine species in a single chromatographic run. The optimized operating conditions (Dionex IonPac AS7, gradient elution with 175 mM ammonium nitrate plus 15% (v/v) methanol, pH 3.8, as a mobile phase and flow rates within the 0.5-1.5 mL min(-1) range) have also been used to perform inorganic bromine speciation analysis (bromide and bromate). The developed method has been applied for determining the bio-available contents of iodine and bromine species in dialyzates from edible seaweed. Reverse phase high performance liquid chromatography (Zorbax Eclipse XDB-C8, gradient elution with 0.2% (m/m) acetic acid, and 0.2% (m/m) acetic acid in methanol, as mobile phases, and a constant flow rate of 0.75 mL min(-1)) also hyphenated with inductively coupled plasma-mass spectrometry was used to confirm the presence of organic iodine species (MIT and DIT) in the dialyzates. The verification of the presence of iodinated amino acids (MIT and DIT) in the extracts was also performed by reverse phase high performance liquid chromatography-electrospray ionization-mass spectrometry (LTQ Orbitrap). The developed methods have provided good repeatability (RSD values lower than 10% for both anion exchange and reverse phase separations) and analytical recoveries within the 90-105% range for all cases. The in vitro bio-availability method consisted of a simulated gastric and an intestinal digestion/dialysis (10 kDa molecular weight cut-off - MWCO) two-stage procedure. Iodide and MIT were the main bio-available species quantified, whereas bromide was the major bromine species found in the extracts. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Finasteride Quantification in Human Plasma by High-Performance Liquid Chromatography Coupled to Electrospray Ionization Tandem Mass Spectrometry. Application to a Comparative Pharmacokinetics Study.

    Science.gov (United States)

    Moreno, R A; Moreno, P; Borges, N C; Donato, J L; Oliveira, S E; Borges, N C

    2015-09-01

    A specific, fast and sensitive LC-MS/MS assay was developed for the determination of finasteride in human plasma using betamethsone dipropionate as the internal standard (IS). The limit of quantification was 1.0 ng/ml and the method was linear in the range of 1.0-25.0 ng/ml. The retention times were 0.75 min for finasteride and 0.85 min for IS. Method intra-batch precision and accuracy ranged from 3.6 to 7.1%, and 96.6 to 103.9%, respectively. Inter-batch precision ranged from 2.5 to 3.4%, while Inter-batch accuracy ranged from 100.3 to 103.5%. The analytical method was applied to evaluate the pharmacokinetic and relative bioavailability of 2 different pharmaceutical formulations containing 1.0 mg of finasteride. This study evaluated 38 volunteers in a randomized, 2-period crossover study with 7 days washout period between doses. The geometric mean and respective 90% CI of finasteride test/reference percent ratios were 95.68% (91.2 - 104.6%) for Cmax, 97.5% (92.1-103.3%) for AUC0-t and 98.1 (92.67-103.8) for AUC0-inf. Based on the 90% confidence interval of the individual ratios (test formulation/reference formulation) for Cmax and AUC0-inf, it was concluded that the test formulation is bioequivalent to the reference one with respect to the rate and extent of absorption of finasteride. © Georg Thieme Verlag KG Stuttgart · New York.

  19. High performance AC drives

    CERN Document Server

    Ahmad, Mukhtar

    2010-01-01

    This book presents a comprehensive view of high performance ac drives. It may be considered as both a text book for graduate students and as an up-to-date monograph. It may also be used by R & D professionals involved in the improvement of performance of drives in the industries. The book will also be beneficial to the researchers pursuing work on multiphase drives as well as sensorless and direct torque control of electric drives since up-to date references in these topics are provided. It will also provide few examples of modeling, analysis and control of electric drives using MATLAB/SIMULIN

  20. High Performance Liquid Chromatography

    Science.gov (United States)

    Talcott, Stephen

    High performance liquid chromatography (HPLC) has many applications in food chemistry. Food components that have been analyzed with HPLC include organic acids, vitamins, amino acids, sugars, nitrosamines, certain pesticides, metabolites, fatty acids, aflatoxins, pigments, and certain food additives. Unlike gas chromatography, it is not necessary for the compound being analyzed to be volatile. It is necessary, however, for the compounds to have some solubility in the mobile phase. It is important that the solubilized samples for injection be free from all particulate matter, so centrifugation and filtration are common procedures. Also, solid-phase extraction is used commonly in sample preparation to remove interfering compounds from the sample matrix prior to HPLC analysis.

  1. Clojure high performance programming

    CERN Document Server

    Kumar, Shantanu

    2013-01-01

    This is a short, practical guide that will teach you everything you need to know to start writing high performance Clojure code.This book is ideal for intermediate Clojure developers who are looking to get a good grip on how to achieve optimum performance. You should already have some experience with Clojure and it would help if you already know a little bit of Java. Knowledge of performance analysis and engineering is not required. For hands-on practice, you should have access to Clojure REPL with Leiningen.

  2. High performance data transfer

    Science.gov (United States)

    Cottrell, R.; Fang, C.; Hanushevsky, A.; Kreuger, W.; Yang, W.

    2017-10-01

    The exponentially increasing need for high speed data transfer is driven by big data, and cloud computing together with the needs of data intensive science, High Performance Computing (HPC), defense, the oil and gas industry etc. We report on the Zettar ZX software. This has been developed since 2013 to meet these growing needs by providing high performance data transfer and encryption in a scalable, balanced, easy to deploy and use way while minimizing power and space utilization. In collaboration with several commercial vendors, Proofs of Concept (PoC) consisting of clusters have been put together using off-the- shelf components to test the ZX scalability and ability to balance services using multiple cores, and links. The PoCs are based on SSD flash storage that is managed by a parallel file system. Each cluster occupies 4 rack units. Using the PoCs, between clusters we have achieved almost 200Gbps memory to memory over two 100Gbps links, and 70Gbps parallel file to parallel file with encryption over a 5000 mile 100Gbps link.

  3. The role of nature-based infrastructure (NBI) in coastal resiliency planning: A literature review.

    Science.gov (United States)

    Saleh, Firas; Weinstein, Michael P

    2016-12-01

    The use of nature-based infrastructure (NBI) has attracted increasing attention in the context of protection against coastal flooding. This review is focused on NBI approaches to improve coastal resilience in the face of extreme storm events, including hurricanes. We not only consider the role of NBI as a measure to protect people and property but also in the context of other ecological goods and services provided by tidal wetlands including production of fish and shellfish. Although the results of many studies suggest that populated areas protected by coastal marshes were less likely to experience damage when exposed to the full force of storm surge, it was absolutely critical to place the role of coastal wetlands into perspective by noting that while tidal marshes can reduce wave energy from low-to-moderate-energy storms, their capacity to substantially reduce storm surge remains poorly quantified. Moreover, although tidal marshes can reduce storm surge from fast moving storms, very large expanses of habitat are needed to be most effective, and for most urban settings, there is insufficient space to rely on nature-based risk reduction strategies alone. The success of a given NBI method is also context dependent on local conditions, with potentially confounding influences from substrate characteristics, topography, near shore bathymetry, distance from the shore and other physical factors and human drivers such as development patterns. Furthermore, it is important to better understand the strengths and weaknesses of newly developed NBI projects through rigorous evaluations and characterize the local specificities of the particular built and natural environments surrounding these coastal areas. In order for the relevant science to better inform policy, and assist in land-use challenges, scientists must clearly state the likelihood of success in a particular circumstance and set of conditions. We conclude that "caution is advised" before selecting a particular NBI

  4. NBI Calculations for the TJ-II Experimental Discharges; Ajustes de los Perfiles Radiales de Densidad y Temperatura para las Descargas con NBI del TJ-II

    Energy Technology Data Exchange (ETDEWEB)

    Guasp, J.; Fuentes, C.; Liniers, M.

    2005-07-01

    The density and electron temperature radial profiles, corresponding to the experimental TJ-II campaigns 2003-2004, with NBI, have been fitted to simple functionals in order to allow a fast approximative evaluation for any given density and injected power... The fits have been calculated, separately, for the four possibilities: ECRH and NBI Phases as well as On and Off Axis ECRH injection. The average difference between the experimental profiles for the individual discharges and the fit predictions are around 8% for the density and 10% for the temperature. The behaviour of the predicted profiles with average line density and injected power has been analysed. The central electron temperature decreases monotonically with increasing density and the ECRH phase On Axis central value is clearly higher than the Off axis one. The radial density profiles narrow with increasing density and the NBI On axis case is clearly wider than de Off one. The electron temperature profile widens slightly with increasing density and the width of the On Axix case is lesser than for the Off case in all phases. There exist Fortran subroutines, available at the three CIEMAT computers, allowing the fast approximative evaluation of all these profiles. (Author) 8 refs.

  5. Mangafodipir trisodium injection, a new contrast medium for magnetic resonance imaging: detection and quantitation of the parent compound MnDPDP and metabolites in human plasma by high performance liquid chromatography.

    Science.gov (United States)

    Toft, K G; Friisk, G A; Skotland, T

    1997-04-01

    Manganese(II) dipyridoxyl diphosphate (MnDPDP) is the active component of mangafodipir trisodium injection (Teslascan), a new contrast medium for magnetic resonance imaging. A high performance liquid chromatography (HPLC) method was developed for the simultaneous determination of MnDPDP and its five major metabolites in human plasma, i.e. the dephosphorylation products MnDPMP (manganese(II) dipyridoxyl monophosphate) and MnPLED (manganese(II) dipyridoxyl ethylenediamine diacetate) and the corresponding substances obtained after transmetallation with zinc (ZnDPDP, ZnDPMP and ZnPLED). Heparinized blood samples from patients receiving mangafodipir trisodium injection were immediately mixed with solid trisodium phosphate dodecahydrate to obtain pH 10.0 +/- 0.2 in order to inhibit further in vitro dephosphorylation and transmetallation. The plasma thus obtained was ultrafiltrated prior to HPLC analysis. The chromatographic separation was obtained using a mixed-bed resin with both anion exchange and reversed-phase functions (OmniPac PAX-500) using isocratic elution and UV detection at 310 nm. With an injection volume of 50 microliters, the limit of quantitation (LOQ) values were 0.8-2.3 microM for the Mn compounds and 0.1-0.8 microM for the Zn compounds. The between-run accuracy of spiked plasma samples was in the range 97.5-106.7% with a precision in the range 3.1-9.0%. The best fit calibration curves were obtained using non-linear regression according to the equation Y = A + BXM in the concentration range from LOQ to 100 microM. Long-term storage of spiked plasma samples for three months at -20 degrees C demonstrated the required stability with recovery values within 85-115% of MnDPDP and its five metabolites.

  6. Development and Validation of a High-Performance Liquid Chromatography Method With UV Detection for Determination of 1-(2-phenylethyl)-5- (quinaldin-4-yl) Biuret in Rat Plasma.

    Science.gov (United States)

    Adibpour, Neda; Ahmadnasr, Maryam; Khodayar, Mohammad Javad; Rezaee, Saeed

    2013-01-01

    Recently, biuret derivatives have been reported as showing moderate to good cytotoxic effect against certain cancer cell lines. In this study, a high-performance liquid chromatography method was developed for determination of 1-(2-phenylethyl)-5-(quinaldin-4-yl) biuret (PEQB) in rat plasma to use in future studies on this compound and related derivatives. In this study, we describe a simple and sensitive high-performance liquid chromatography method with UV detection for determination of 1-(2-phenylethyl)-6-(quinaldin-4-yl) biuret (PEQB) in rat plasma. Separations were performed on a Nucleosil-100 CN HPLC column (125 × 4.0 mm) (5 µm), using a mixture of acetonitrile: methanol: potassium dihydrogen phosphate buffer (0.05 M, pH 3.5) (10:10:80) as mobile phase delivered at a flow rate of 1 mL/minute. Detection of PEQB and internal standard (1-([[3-(1,3-benzothiazol-2-ylsulfanyl)propyl]carbamoyl]amino)-N-phenylformamide) was performed at 235 nm and ambient temperature. Plasma samples (200 µL) were prepared by addition of 40 µL internal standard (100 µg/mL), and 400 µL acetonitrile. After vortex mixing and centrifugation at 10000 g, 50 µL of the clear supernatant was directly injected onto the chromatography column. Calibration curves were constructed by fitting the peak area ratio of the biuret to internal standard against concentration of biuret to a power model using generalized least squares nonlinear regression method. Under the above chromatography condition, biuret compound (PEQB) and the internal standard were detected at 4.5 and 13.5 minutes, respectively. Limit of quantitation of the PEQB was 0.1 µg/mL. Accuracy of the method over the concentration range of 0.1-100 µg/mL was between 88-109%. Inter- and intraday precisions were 4-19% and 6-8%, respectively. A good relationship in the form of a power model was found for two separate concentration ranges of 0.1-1 and 2.5-100 µg/mL (R (2)> 0.99). The presented simple HPLC method is sufficiently accurate

  7. Narrow band imaging (NBI cystoscopy and assisted bipolar TURBT: A preliminary experience in a single centre

    Directory of Open Access Journals (Sweden)

    Roberto Giulianelli

    2017-10-01

    Full Text Available Objective: The aim of this study was to compare, in order to increase our ability to detect bladder cancer, the predictive power of narrow band imaging (NBI versus white light cystoscopy (WL. The secondary objective was to evaluate how the preoperative use of NBI cystoscopy can increase the ability to detect bladder lesions in terms of status, multi-focality and dimensions. Materials and methods: Between June 2010 and April 2012, 797 consecutive patients, 423 male and 374 female, affected by suspected bladder cancer lesions, underwent to WL plus NBI cystoscopy and subsequently to WL Bipolar Gyrus PK (Olympus, Tokyo, Japan transurethral resection of bladder tumour (WL-TURBT. The average follow-up was 24 (16-38 months. Mean age was 67.7 yrs. (range 46-88. All the patients underwent by same surgeon to WL resection (WL-TURBT of the previously identified lesions by same surgeon. All the removed tissue was sent separately for histological evaluation after mapping the areas of resection on a topographic sheet. Results: In our study we considered 797 patients that matched our inclusion criteria. Through the use of WL cystoscopy, we identified 603 patients (75.53% with suspicious lesions, instead, with the use of light NBI, we found 786 patients with suspicious lesions (98.49%.The use of NBI cystoscopy increases by approximately 30% the specific ability to detect lesions not otherwise visible with WL cystoscopy (OR 21.9 and RR 1.30, in particular for patients with lesions size < 3 cm (OR 24.00; RR 1.40, unifocal (OR: 22.28; RR 1.47 and recurrent (OR 58.4; RR 1.34. Pathology demonstrated the presence of cancer in 512 (64.2% patients, of whom 412 (51.8% were visible both with WL cystoscopy and NBI cystoscopy. In our experience, only 11 (1.38% lesions were only positive at WL cystoscopy (negative at NBI cystoscopy thus 501 (62.8%, OR 10.13; RR 1.21 patients showed bladder oncological lesions positive at NBI cystoscopy. In these patients, the use the NBI

  8. High Performance Network Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Jesse E [Los Alamos National Laboratory

    2012-08-10

    Network Monitoring requires a substantial use of data and error analysis to overcome issues with clusters. Zenoss and Splunk help to monitor system log messages that are reporting issues about the clusters to monitoring services. Infiniband infrastructure on a number of clusters upgraded to ibmon2. ibmon2 requires different filters to report errors to system administrators. Focus for this summer is to: (1) Implement ibmon2 filters on monitoring boxes to report system errors to system administrators using Zenoss and Splunk; (2) Modify and improve scripts for monitoring and administrative usage; (3) Learn more about networks including services and maintenance for high performance computing systems; and (4) Gain a life experience working with professionals under real world situations. Filters were created to account for clusters running ibmon2 v1.0.0-1 10 Filters currently implemented for ibmon2 using Python. Filters look for threshold of port counters. Over certain counts, filters report errors to on-call system administrators and modifies grid to show local host with issue.

  9. Rapid high-performance liquid chromatography-tandem mass spectrometry method for simultaneous measurement of venlafaxine and O-desmethylvenlafaxine in human plasma and its application in comparative bioavailability study.

    Science.gov (United States)

    Rajasekhar, D; Kumar, I Jaswanth; Venkateswarlu, P

    2009-12-01

    A rapid high-performance liquid chromatography-tandem mass spectrometry method has been developed and validated for simultaneous measurement of venlafaxine and O-desmethylvenlafaxine in human plasma using fluoxetine as an internal standard. In the liquid-liquid extraction method, compounds and internal standard were extracted from plasma using methyl tertiary butyl ether as an extraction solvent. The HPLC separation of the analytes was performed on a Zorbax SB-C(18), 50 x 4.6 mm, 5 microm column, using a isocratic elution program using a mobile phase consisting of HPLC-grade methanol: 5 mm ammonium acetate (80:20 v/v) at a flow-rate of 1.0 mL/min with a total runtime of 3.0 min. The proposed method has been validated with a linear range of 4-400 ng/mL for venlafaxine and 5-500 ng/mL for O-desmethyl venlafaxine. The method was applied for a bio-equivalence study of 75 mg tablets formulation in 32 Indian male healthy subjects under fasting conditions.

  10. Optimization and validation of high performance liquid ...

    African Journals Online (AJOL)

    Optimization and validation of high performance liquid chromatography-ultra violet method for quantitation of metoprolol in rabbit plasma: application to ... Methods: Mobile phase of methanol and 50 mM ammonium dihydrogen phosphate solution (50:50) at pH 3.05 was used for separation of metoprolol on BDS hypersil ...

  11. Rapid high performance liquid chromatographic determination of ...

    African Journals Online (AJOL)

    Rapid high performance liquid chromatographic determination of chlorpropamide in human plasma. MTB Odunola, IS Enemali, M Garba, OO Obodozie. Abstract. Samples were extracted with dichloromethane and the organic layer evaporated to dryness. The residue was dissolved in methanol, and 25 ìl aliquot injected ...

  12. The Development of Data Acquisition and Remote Real-Time Display System for EAST NBI

    Science.gov (United States)

    Zhang, Xiaodan; Hu, Chundong; Sheng, Peng; Zhao, Yuanzhe; Wu, Deyun; Cui, Qinglong

    2013-10-01

    The data acquisition and remote real-time display system for the neutral beam injectors (NBI) on experimental advanced superconducting tokamak (EAST) are described in this paper. Distributed computer systems including local data acquisition (DAQ) facility, remote data server (DS), real-time display terminal are adopted with Linux and Windows operating system. Experimental signals are gathered by DAQ device at local working field. On the one hand, these gathered data will be sent to DS which runs on remote server main control layer on EAST NBI control network for saving and processing; on the other hand, these data will be sent to real-time display terminal which runs on remote monitoring layer on EAST NBI for displaying and monitoring experimental signals real-timely. Another point needs to be mentioned is that the real-time display software can call back historical data from DS for querying. The software of data acquisition and DS are programmed by C language while the real-time display software is programmed by Labview flow chart. The hardware mainly includes DAQ cards, server, industrial personal computer and others auxiliary hardware. Now the system proved to be performed well through experiments on NBI testing bed.

  13. Determination of unbound vismodegib (GDC-0449) concentration in human plasma using rapid equilibrium dialysis followed by solid phase extraction and high-performance liquid chromatography coupled to mass spectrometry.

    Science.gov (United States)

    Deng, Yuzhong; Wong, Harvey; Graham, Richard A; Liu, Wenbin; Shen, Heuy-shin; Shi, Yao; Wang, Laixin; Meng, Min; Malhi, Vikram; Ding, Xiao; Dean, Brian

    2011-07-15

    A rapid equilibrium dialysis (RED) assay followed by a solid phase extraction (SPE) high-performance liquid chromatography tandem mass spectrometry (LC-MS/MS) assay for the quantitative determination of unbound vismodegib in human plasma was developed and validated. The equilibrium dialysis was carried out using 0.3 mL plasma samples in the single-use plate RED system at 37°C for 6h. The dialysis samples (0.1 mL) were extracted using a Strata-X-C 33u Polymeric Strong Cation SPE plate and the resulting extracts were analyzed using reverse-phase chromatography and positive electrospray ionization (ESI) mass spectrometry. The standard curve, which ranged from 0.100 to 100 ng/mL for vismodegib, was fitted to a 1/x(2) weighted linear regression model. The lower limit of quantitation (LLOQ, 0.100 ng/mL) was sufficient to quantify unbound concentrations of vismodegib after dialysis. The intra-assay precision of the LC-MS/MS assay, based on the four analytical QC levels (LLOQ, low, medium and high), was within 7.7% CV and inter-assay precision was within 5.5% CV. The assay accuracy, expressed as %Bias, was within ±4.0% of the nominal concentration values. Extraction recovery of vismodegib was between 77.9 and 84.0%. The assay provides a means for accurate assessment of unbound vismodegib plasma concentrations in clinical studies. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Fiber-based liquid-phase micro-extraction of mebeverine enantiomers followed by chiral high-performance liquid chromatography analysis and its application to pharmacokinetics study in rat plasma.

    Science.gov (United States)

    Hatami, Mehdi; Farhadi, Khalil; Tukmechi, Amir

    2012-08-01

    The applicability of two-phase liquid-phase micro-extraction (LPME) in porous hollow polypropylene fiber for the sample preparation and the stereoselective pharmacokinetics of mebeverine (MEB) enantiomers (an antispasmodic drug) in rat after intramuscular administration were studied. Plasma was assayed for MEB enantiomer concentrations using stereospecific high-performance liquid chromatography with ultraviolet detection after a simple, inexpensive, and efficient preconcentration and clean-up hollow fiber-based LPME. Under optimized micro-extraction conditions, MEB enantiomers were extracted with 25 µl of 1-octanol within a lumen of a hollow fiber from 0.5 ml of plasma previously diluted with 4.5 ml alkalized water (pH 10). The chromatographic analysis was carried out through chiral liquid chromatography using a DELTA S column and hexane-isopropyl alcohol (85:15 v/v) containing 0.2% triethylamine as mobile phase. The mean recoveries of (+)-MEB and (-)-MEB were 75.5% and 71.0%, respectively. The limit of detection (LOD) was 3.0 ng/ml with linear response over the concentration range of 10-2500 ng/ml with correlation coefficient higher than 0.993 for both enantiomers. The pharmacokinetic studies showed that the mean plasma levels of (+)-MEB were higher than those of (-)-MEB at almost all time points. Also, (+)-MEB exhibited greater t(max) (peak time in concentration-time profile), C(max) (peak concentration in concentration-time profile), t(1/2) (elimination half-life), and AUC(0-240 min) (area under the curve for concentration versus time) and smaller CL (clearance) and V(d) (apparent distribution volume) than its antipode. The obtained results implied that the absorption, distribution, and elimination of (-)-MEB were more rapid than those of (+)-MEB and there were stereoselective differences in pharmacokinetics. Copyright © 2012 Wiley Periodicals, Inc.

  15. Langmuir probe studies on a RF ion source for NBI

    Energy Technology Data Exchange (ETDEWEB)

    McNeely, P. E-mail: p.mcneely@ipp.mpg.de; Heineman, B.; Kraus, W.; Riedl, R.; Speth, E.; Vollmer, O

    2001-10-01

    IPP Garching has been developing a RF ion source for H{sup -} production. In order to improve the data quality a new scanning probe system with passive RF compensation has been installed on the Type VI ion source on the BATMAN test stand. Using this probe, measurements have been carried out to study changes to the plasma parameters (electron density, electron temperature, and plasma potential) due to variation in the source operating conditions. The data were collected at a source pressure of 0.5 Pa and with 60{+-}5 kW applied RF power. Presented are some of the results of these measurements, focusing on the effect of: argon seeding, addition of Cs to the source, and the newly added Faraday screen. The electron density behaves in a fashion that agrees with the theory of ambipolar diffusion. Typically there is little change to the average electron energy observed regardless of which effect is considered. The plasma potential shows the most significant changes with external source conditions, both in value for all cases and shape when the Faraday screen was added.

  16. Quantification of 3α-hydroxytibolone in human plasma by high performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS: Application in a bioequivalence study in healthy postmenopausal volunteers

    Directory of Open Access Journals (Sweden)

    Lucas Azevedo Portela

    2016-06-01

    Full Text Available A sensitive, specific and fast method to quantify 3α-hydroxytibolone in human plasma using deuterated 3α-hydroxytibolone (d5 as internal standard is described. The analyte and the internal standard were extracted from plasma (900 μL by liquid-liquid extraction using ethyl ether/hexane (50/50, v/v and ammonium hydroxide (50%. The extracts were analyzed by high performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry without derivatization. Chromatography was performed isocratically on a Gemini-NX™ C18 5 μm (150 × 4.6 mm i. d. column. The method had a chromatographic run time of 3.75 min and a linear calibration curve over the range 1–100 ng/mL. The limit of quantification validated was 1 ng/mL. This method was used to assess the bioequivalence between two different tibolone oral formulations: Livolon (1.25 mg tablet provided by Biolab Sanus Farmacêutica (Brazil, as the test formulation, and Libiam™ (1.25 mg tablet produced by Libbs Farmacêutica (Brazil, as the reference formulation. A single 3.75 mg dose of each formulation was administered to 46 postmenopausal female healthy volunteers. The study was conducted in an open, randomized, two-period crossover balanced design with a 2 week washout interval between the doses. The 90% confidence interval for Cmax, AUC(0-last and AUC(0-inf individual test/reference ratios were 97.48–111.51, 95.35–103.20 and 96.42–103.86, respectively. It is concluded that Livolon (1.25 mg tablet is bioequivalent to Libiam™ (1.25 mg tablet, with regards to both rate and extent of absorption.

  17. Fast speciation of mercury in seawater by short-column high-performance liquid chromatography hyphenated to inductively coupled plasma spectrometry after on-line cation exchange column preconcentration.

    Science.gov (United States)

    Jia, Xiao-Yu; Gong, Di-Rong; Han, Yi; Wei, Chao; Duan, Tai-Cheng; Chen, Hang-Ting

    2012-01-15

    A simple and fast method for trace speciation analysis of mercury (Hg(2+)), methylmercury (MeHg(+)) and ethylmercury (EtHg(+)) in seawater has been developed by short-column high-performance liquid chromatography hyphenated to inductively coupled plasma spectrometry (HPLC-ICP-MS) after on-line cation-exchange column (CEC) preconcentration. The analytes were firstly adsorbed on the CEC without any extraneous reagent, and then were eluted rapidly (within seconds) and completely with a very low concentration of l-cysteine solution, which provides the conveniency for the on-line coupling of the preconcentration method and detection technique. To our best knowledge, it is for the first time to employ the CEC preconcentration technique to trap all of the three mercury species simultaneously at their positive charged status for the purpose of speciation analysis. Under the optimized conditions, a very high preconcentration factor up to 1250 has been obtained with 30mL sample solution, which leads to the very low detection limits of 0.042ngL(-1) for Hg(2+), 0.016ngL(-1) for MeHg(+) and 0.008ngL(-1) for EtHg(+) (as Hg), respectively. With the established method, three seawater samples were also analyzed, and all the three mercury species have been found in each sample, albeit at a very low concentration. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

  18. Simultaneous Determination of Purpurin, Munjistin and Mollugin in Rat Plasma by Ultra High Performance Liquid Chromatography-Tandem Mass Spectrometry: Application to a Pharmacokinetic Study after Oral Administration of Rubia cordifolia L. Extract

    Directory of Open Access Journals (Sweden)

    Mingjie Gao

    2016-06-01

    Full Text Available A specific, simple, sensitive Ultra High Performance Liquid Chromatography-tandem Mass Spectrometry (UHPLC-MS/MS method has been developed and validated for the simultaneous determination and pharmacokinetic study of purpurin, munjistin, and mollugin in rat plasma. Chromatographic separation was carried out using a C18 column (ACQUITY UPLC® HSS T3, 1.8 μm, 2.1 × 100 mm with gradient elution. The compounds were detected on a 6430 triple-quadrupole tandem MS with an electrospray ionization (ESI interface using multiple reaction monitoring (MRM in positive ionization mode. The samples were prepared by a liquid-liquid extraction (LLE method with ethyl acetate after being spiked with an internal standard (bifendate. The current UHPLC-MS/MS assay was validated for its linearity, intra-day and inter-day precisions, accuracy, extraction recovery, matrix effect and stability in different conditions. The method was linear for all analytes over the investigated range with all determined correlation coefficients exceeding 0.9900. The intra-day and inter-day precisions were in the range of 4.21% to 14.84%, and the relative errors of accuracies were in the range of −14.05% to 14.75%. The mean recoveries and matrix effects of purpurin, munjistin, and mollugin were higher than 78.87% and 92.56%, repectively. After oral administration of 0.82 g/kg of Rubia cordifolia extract, the maximum plasma concentrations (Cmax were 70.10 ± 11.78 ng/mL for purpurin, 26.09 ± 6.6 ng/mL for munjistin, and 52.10 ± 6.71 ng/mL for mollugin. The time for maximal concentration (Tmax was 1.61 ± 0.24 h for purpurin, 2.58 ± 0.19 h for munjistin, and 1.99 ± 0.21 h for mollugin. The established method was further applied to a pharmacokinetic study of purpurin, munjistin, and mollugin in rat plasma. It was concluded from the pharmacokinetic parameters that the three analytes showed a process of slow absorption and metabolism after oral administration of R. cordifolia extract to

  19. A fabric phase sorptive extraction-High performance liquid chromatography-Photo diode array detection method for the determination of twelve azole antimicrobial drug residues in human plasma and urine.

    Science.gov (United States)

    Locatelli, Marcello; Kabir, Abuzar; Innosa, Denise; Lopatriello, Teresa; Furton, Kenneth G

    2017-01-01

    This paper reports a novel fabric phase sorptive extraction-high performance liquid chromatography-photodiode array detection (FPSE-HPLC-PDA) method for the simultaneous extraction and analysis of twelve azole antimicrobial drug residues that include ketoconazole, terconazole, voriconazole, bifonazole, clotrimazole, tioconazole, econazole, butoconazole, miconazole, posaconazole, ravuconazole, and itraconazole in human plasma and urine samples. The selected azole antimicrobial drugs were well resolved by using a Luna C18 column (250mm×4.6mm; 5μm particle size) in gradient elution mode within 36min. The analytical method was calibrated and validated in the range from 0.1 to 8μg/mL for all the drug compounds. Blank human plasma and urine were used as the sample matrix for the analysis; while benzyl-4-hydroxybenzoate was used as the internal standard (IS). The limit of quantification of the FPSE-HPLC-PDA method was found as 0.1μg/mL and the weighted-matrix matched standard calibration curves of the drugs showed a good linearity upto a concentration of 8μg/mL. The parallelism tests were also performed to evaluate whether overrange sample can be analyzed after dilution, without compromising the analytical performances of the validated method. The intra- and inter-day precision (RSD%) values were found ≤13.1% and ≤13.9%, respectively. The intra- and inter-day trueness (bias%) values were found in the range from -12.1% to 10.5%. The performances of the validated FPSE-HPLC-PDA were further tested on real samples collected from healthy volunteers after a single dose administration of itraconazole and miconazole. To the best of our knowledge, this is the first FPSE extraction procedure applied on plasma and urine samples for the simultaneous determination of twelve azole drugs possessing a wide range of logKow values (extending from 0.4 for fluconazole to 6.70 of butoconazole) and could be adopted as a rapid and robust green analytical tool for clinical and

  20. Progress of negative-ion based NBI system for JT-60U

    Energy Technology Data Exchange (ETDEWEB)

    Kuriyama, M.; Akino, N.; Ebisawa, N.; Grisham, L.; Honda, A.; Itoh, T.; Kawai, M.; Kazawa, M.; Kusaka, M.; Liquen, H.; Mogaki, K.; Ohga, T.; Ohmori, K.; Ohshima, K.; Okumura, Y.; Oohara, H.; Satoh, F.; Seki, H.; Tanai, Y.; Toyokawa, Y.; Usui, K.; Watanabe, K.; Yamaguchi, M.; Yamazaki, H.; Yamazaki, T. [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    1998-07-01

    The operation of the negative ion based NBI system for JT-60U has been progressed since 1996. Most of the efforts in the operation for increasing beam power and energy have been concentrated to get over the troubles, caused by surge energy at the moment of the accelerator break-down, in the ion sources and high voltage power supplies. The ion source for the N-NBI, so far, has accelerated negative ion beams of 14.3 A at 380 keV with deuterium and 18.5 A at 360 keV with hydrogen against the target of 22 A. The neutral beam power injected into JT-60U has already reached 5.2 MW at 350 keV for 0.7 sec with deuterium. (author)

  1. Shielding of the NBI boxes against W7-X magnetic stray fields

    Energy Technology Data Exchange (ETDEWEB)

    Kick, Manfred [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstr. 2, D-85748 Garching (Germany)], E-mail: Kick@arcor.de; Sielanko, Juliusz [Maria Curie Sklodowska University, Pl. M. C. Sklodowskie 1, 20-031 Lublin (Poland); Heinemann, Bernd; Riedl, Rudolf; Speth, Eckehart; Staebler, Albrecht [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstr. 2, D-85748 Garching (Germany)

    2009-06-15

    Neutral Beam Injection (NBI), besides ECRH, is foreseen as one of the main heating devices at the W7-X stellarator currently under construction at IPP Greifswald, Germany. In a final stage 20 MW of NBI heating power will be installed generated by two NBI boxes of the ASDEX Upgrade (AUG) type. Since magnetic fields generally affect the trajectories of charged particles, essentially all the NBI boxes - including ion sources, acceleration sections, neutralisers and deflection magnets - must be shielded against the stray fields of W7-X. In the magnetic stray fields of W7-X there exist significant radial and toroidal components whereas at tokamaks the vertical components are dominant. The power loads on the ion dump and the protecting structures of the deflecting magnets and the beam lines caused by residual beam ions, therefore, will be strongly different. Thus the shielding concept of AUG cannot simply be taken over, but must be carefully redesigned in order to remain below the critical power limits. New modelling calculations of the magnetic shielding, the ion trajectories and the resulting power loads have been carried out for the 'high iota' and 'low shear' experimental scenarios of W7-X. The fields taken for these calculations are modelled by averaging the calculated W7-X stray fields on the one hand, and by fields generated by two-hypothetical-planar coils perpendicular to the x-y plane, on the other hand. The shielding concept for W7-X mainly consist of iron plates in the outer side regions of the boxes and as little magnetic material as possible inside the boxes.

  2. Design of a -1 MV dc UHV power supply for ITER NBI

    Science.gov (United States)

    Watanabe, K.; Yamamoto, M.; Takemoto, J.; Yamashita, Y.; Dairaku, M.; Kashiwagi, M.; Taniguchi, M.; Tobari, H.; Umeda, N.; Sakamoto, K.; Inoue, T.

    2009-05-01

    Procurement of a dc -1 MV power supply system for the ITER neutral beam injector (NBI) is shared by Japan and the EU. The Japan Atomic Energy Agency as the Japan Domestic Agency (JADA) for ITER contributes to the procurement of dc -1 MV ultra-high voltage (UHV) components such as a dc -1 MV generator, a transmission line and a -1 MV insulating transformer for the ITER NBI power supply. The inverter frequency of 150 Hz in the -1 MV power supply and major circuit parameters have been proposed and adopted in the ITER NBI. The dc UHV insulation has been carefully designed since dc long pulse insulation is quite different from conventional ac insulation or dc short pulse systems. A multi-layer insulation structure of the transformer for a long pulse up to 3600 s has been designed with electric field simulation. Based on the simulation the overall dimensions of the dc UHV components have been finalized. A surge energy suppression system is also essential to protect the accelerator from electric breakdowns. The JADA contributes to provide an effective surge suppression system composed of core snubbers and resistors. Input energy into the accelerator from the power supply can be reduced to about 20 J, which satisfies the design criteria of 50 J in total in the case of breakdown at -1 MV.

  3. High-performance sports medicine

    National Research Council Canada - National Science Library

    Speed, Cathy

    2013-01-01

    High performance sports medicine involves the medical care of athletes, who are extraordinary individuals and who are exposed to intensive physical and psychological stresses during training and competition...

  4. Selenium speciation in radix puerariae using ultrasonic assisted extraction combined with reversed phase high performance liquid chromatography-inductively coupled plasma-mass spectrometry after magnetic solid-phase extraction with 5-sulfosalicylic acid functionalized magnetic nanoparticles

    Science.gov (United States)

    Cao, Yupin; Yan, Lizhen; Huang, Hongli; Deng, Biyang

    2016-08-01

    A new method for determination of selenium species in radix puerariae was described. The method consists of sample enrichment with 5-sulfosalicylic acid (SSA)-functionalized silica-coated magnetic nanoparticles (SMNPs), high performance liquid chromatography (HPLC) separation, and online detection using inductively coupled plasma mass spectrometry (ICP-MS). The selenium species were extracted using ultrasonic extraction system with a mixture of protease K and lipase. The SSA-SMNPs were used to enrich trace amounts of selenite [Se(IV)], selenate [Se(VI)], selenomethionine (SeMet), and selenocystine (SeCys2) from lower selenium containing samples. Under the optimal conditions, the limits of detection (3σ) for SeCys2, Se(IV), SeMet and Se(VI) were observed as 0.0023, 0.0015, 0.0043, and 0.0016 ng mL- 1, respectively. The RSD values (n = 6) of method for intraday were observed between 0.5% and 0.9%. The RSD values of method for interday were less than 1.3%. The linear concentration ranges for SeCys2, Se(IV), SeMet and Se(VI) were 0.008-1000, 0.005-200, 0.015-500 and 0.006-200 ng mL- 1, respectively. The detection limits of this method were improved by 10 times due to the enrichment with the SSA-SMNP extraction. The contents of SeCys2, Se(IV), SeMet, and Se(VI) in radix puerariae were determined as 0.0140, 0.171, 0.0178, and 0.0344 μg g- 1, respectively. The recoveries were in the range of 95.6%-99.4% and the RSDs (n = 6) of recoveries were less than 1.5%.

  5. Simultaneous Determination of Eight β-Lactam Antibiotics, Amoxicillin, Cefazolin, Cefepime, Cefotaxime, Ceftazidime, Cloxacillin, Oxacillin, and Piperacillin, in Human Plasma by Using Ultra-High-Performance Liquid Chromatography with Ultraviolet Detection.

    Science.gov (United States)

    Legrand, Tiphaine; Vodovar, Dominique; Tournier, Nicolas; Khoudour, Nihel; Hulin, Anne

    2016-08-01

    A simple and rapid ultra-high-performance liquid chromatography (UHPLC) method using UV detection was developed for the simultaneous determination of eight β-lactam antibiotics in human plasma, including four penicillins, amoxicillin (AMX), cloxacillin (CLX), oxacillin (OXA), and piperacillin (PIP), and four cephalosporins, cefazolin (CFZ), cefepime (FEP), cefotaxime (CTX), and ceftazidime (CAZ). One hundred-microliter samples were spiked with thiopental as an internal standard, and proteins were precipitated by acetonitrile containing 0.1% formic acid. Separation was achieved on a pentafluorophenyl (PFP) column with a mobile phase composed of phosphoric acid (10 mM) and acetonitrile in gradient elution mode at a flow rate of 500 μl/min. Detection was performed at 230 nm for AMX, CLX, OXA, and PIP and 260 nm for CFZ, FEP, CTX, and CAZ. The total analysis time did not exceed 13 min. The method was found to be linear at concentrations ranging from 2 to 100 mg/liter for each compound, and all validation parameters fulfilled international requirements. Between- and within-run accuracy errors ranged from -5.2% to 11.4%, and precision was lower than 14.2%. This simple method requires small-volume samples and can easily be implemented in most clinical laboratories to promote the therapeutic drug monitoring of β-lactam antibiotics. The simultaneous determination of several antibiotics considerably reduces the time to results for clinicians, which may improve treatment efficiency, especially in critically ill patients. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  6. Titania immobilized polypropylene hollow fiber as a disposable coating for stir bar sorptive extraction-high performance liquid chromatography-inductively coupled plasma mass spectrometry speciation of arsenic in chicken tissues.

    Science.gov (United States)

    Mao, Xiangju; Chen, Beibei; Huang, Chaozhang; He, Man; Hu, Bin

    2011-01-07

    The bottleneck of applying stir bar sorptive extraction (SBSE) to elemental speciation analysis is lack of suitable extraction phases with good affinities to different elemental species. In this paper, a newly high polar extraction phase of titania immobilized polypropylene hollow fiber (TiO₂-PPHF) was prepared by sol-gel immersion and low temperature hydrothermal process and the obtained TiO₂-PPHF inherits the adsorption properties of TiO₂ and the toughness of PPHF. With a suitable size of stainless steel magnetic bar inserted into the prepared TiO₂-PPHF, a disposable TiO₂-PPHF coating stir bar was obtained. The prepared TiO₂-PPHF was characterized by X-ray diffraction spectrometry and scanning electron microscopy and the significant parameters affecting the extraction efficiency of different arsenic species were studied. Based on the above facts, a new method of SBSE combined with high performance liquid chromatography (HPLC)-inductively coupled plasma mass spectrometry (ICP-MS) was developed for the speciation of phenyl arsenic compounds and their possible transformation products in chicken tissues. Under the optimal conditions, limits of detection (LODs) of the developed method for eight target arsenic species were in the range of 11.4-64.6 ng L⁻¹ with enrichment factors of 8.5-22.3 (theory enrichment factor was 50), and the relative standard deviations (RSDs) were varying from 6.3 to 12.6% (c(AsIII/V)=5 μg L⁻¹, c(MMA,DMA,p-ASA,4-OH,3-NHPAA,PA,4-NPAA)=10 μg L⁻¹, n=7). The proposed method was successfully applied to the speciation of arsenic in chicken meat/liver samples and the recoveries for the spiked samples were in the range of 78.5-120.4%. In order to validate the accuracy of the proposed method, a certified reference material of BCR-627 tuna fish tissue was analyzed and the determined values were in good agreement with the certified values. The TiO₂-PPHF was demonstrated to be a highly selective coating for the target arsenic

  7. High Performance Space Pump Project

    Data.gov (United States)

    National Aeronautics and Space Administration — PDT is proposing a High Performance Space Pump based upon an innovative design using several technologies. The design will use a two-stage impeller, high temperature...

  8. RavenDB high performance

    CERN Document Server

    Ritchie, Brian

    2013-01-01

    RavenDB High Performance is comprehensive yet concise tutorial that developers can use to.This book is for developers & software architects who are designing systems in order to achieve high performance right from the start. A basic understanding of RavenDB is recommended, but not required. While the book focuses on advanced topics, it does not assume that the reader has a great deal of prior knowledge of working with RavenDB.

  9. Improvement of the ion source power supply for JT-60 negative-ion based NBI

    Energy Technology Data Exchange (ETDEWEB)

    Omori, K.; Usui, K.; Ohshima, K.; Ohga, T.; Kawai, M.; Watanabe, K.; Itoh, T.; Kuriyama, M. [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment; Ono, Y. [Hitachi Ltd (Japan); Kawashima, S. [Toshiba Corp. (Japan)

    1998-07-01

    In the operation of the N-NBI since 1996, many troubles in the power supplies both the negative-ion generation/extraction and the acceleration have been experienced. Most of the problems broken out in the operation have been caused by the ion source breakdown when increasing the beam power. Those have been solved by altering the components of the power supply hardware and remodeling of the control system and an injection power of 5.2 MW at 350 keV has already been obtained. (author)

  10. Design of a new P-NBI control system for 100-s injection in JT-60SA

    Energy Technology Data Exchange (ETDEWEB)

    Okano, F. [Fusion Research and Development Directorate, Japan Atomic Energy Agency, Naka, Ibaraki-ken 311-0193 (Japan)], E-mail: okano.fuminori@jaea.go.jp; Shinozaki, S.; Honda, A.; Ooshima, K. [Fusion Research and Development Directorate, Japan Atomic Energy Agency, Naka, Ibaraki-ken 311-0193 (Japan); Numazawa, S. [Streem Corporation, Hitachinaka, Ibaraki-ken 312-0062 (Japan); Ikeda, Y. [Fusion Research and Development Directorate, Japan Atomic Energy Agency, Naka, Ibaraki-ken 311-0193 (Japan)

    2008-04-15

    Modification of JT-60U to a superconducting device (so-called JT-60SA) has been planned to contribute to ITER and DEMO. The positive-ion-based NBI system (P-NBI) is required to inject 24 MW for 100 s with 12 units. The P-NBI control system is to be fully remodeled with PLC (Programmable Logic Controller), which is featured by high market availability, system extensibility, cost-effectiveness, and independent development in programming. One of the critical issues to apply the PLC to the P-NBI control system is to control quickly the high voltage power supplies within 200 {mu}s. For this purpose, the fastest PLC dealing with 4 refresh words at the processing time of 200 {mu}s is to be employed. The second issue is to construct a data acquisition system for such a large number of data channels ({approx}2300 digital and {approx}1300 analog data channels). The use of PLC linked with PC-based data measurement devices via Ethernet allows processing the large number of channels. The third issue is to make the man-machine interface simple. The marketed software giving an easy product of graphic menus is available for PLC programming. From these results, it is expected that commercial PLC could be applied to the large-scale control system of the P-NBI system for 100 s operations.

  11. MHD instabilities and their effects on plasma confinement in the large helical device plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Toi, K.; Ohdachi, S. [National Inst. for Fusion Science, Toki, Gifu (Japan); Yamamoto, S. [Nagoya Univ., Dept. of Energy Engineering and Science, Nagoya, Aichi (JP)] [and others

    2002-11-01

    Characteristics of MHD instabilities and their impacts on plasma confinement are studied in current free plasmas of the Large Helical Device (LHD). Spontaneous L-H transition is often observed in high beta plasmas in the range of 2% averaged beta at low toroidal field (B{sub t} {<=} 0.6T). The stored energy rapidly rises with the transition, but quickly saturates due to the growth of m=2/n=3 and m=2/n=2 modes (m and n: poloidal and toroidal mode numbers) excited in the plasma edge region. Even in low beta plasmas, ELM activities are sometimes induced in high performance plasmas with a steep edge pressure gradient, and transiently reduce the stored energy by about 10%. Energetic ion driven MHD modes such as Alfven eigenmodes are studied in the very wide range of characteristic parameters: the averaged beta of energetic ions <{beta}{sub b//}> up to 5% and the ratio of energetic ion velocity to the Alfven velocity V{sub b//}/V{sub A} up to 2.5. In addition to the observation of toroidicity induced Alfven eigenmodes (TAEs), coherent magnetic fluctuations of helicity induced Alfven eigenmodes (HAEs) have been observed for the first time in NBI heated plasmas. The transition of the TAE to the global Alfven eigenmode (GAE) is also observed in a discharge with temporal evolution of the rotational transform profile, having a similarity to the phenomenon in a reversed shear tokamak. At low magnetic field, bursting TAEs transiently induce a significant loss of energetic ions, but lead to the transient improvement of bulk plasma confinement in the plasma central region. (author)

  12. MHD instabilities and their effects on plasma confinement in the large helical device plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Toi, K.; Ohdachi, S. [National Inst. for Fusion Science, Toki, Gifu (Japan); Yamamoto, S. [Nagoya Univ., Dept. of Energy Engineering and Science, Nagoya, Aichi (JP)] [and others

    2002-10-01

    Characteristics of MHD instabilities and their impacts on plasma confinement are studied in current free plasmas of the Large Helical Device (LHD). Spontaneous L-H transition is often observed in high beta plasmas in the range of 2% averaged beta at low toroidal field (B{sub t} {<=} 0.6 T). The stored energy rapidly rises by the transition, but quickly saturates by the growth of m=2/n=3 and m=2/n=2 modes (m and n: poloidal and toroidal mode numbers) excited in the plasma edge region. Even low beta plasmas, ELM like activities are sometimes induced in high performance plasmas with high edge pressure pedestal, and transiently reduce the stored energy by about 10%. Energetic ion driven MHD modes such as Alfven eigenmodes are studied in the very wide parameter range of the averaged beta of energetic ions <{beta}{sub b} sub (parallel)> up to 5% and the ratio of energetic ion velocity to the Alfven velocity V{sub b} sub (parallel)/V{sub A} up to 2.5. In addition to the observation of toroidicity induced Alfven eigenmodes (TAEs), coherent magnetic fluctuations of helicity induced Alfven eigenmodes (HAEs) have been observed for the first time in NBI heated plasmas. Transition of TAE to global Alfven eigenmode (GAE) is also observed in a discharge with temporal evolution of the rotational transform profile, having a similarity to the phenomenon in a reversed shear tokamak. At the low magnetic field, bursting TAEs enhance energetic ion loss transiently, but lead to the transient improvement of bulk plasma confinement in the plasma central region. (author)

  13. Development and Validation of Reverse Phase High Performance ...

    African Journals Online (AJOL)

    Purpose: To develop a sensitive and validated reverse phase-high performance liquid chromatographic. (RP-HPLC) method for quantification of olanzapine in micro-sample of rat plasma using UV detection. Methods: A single oral dose of olanzapine (7 mg/kg) was given to overnight fasted rats (n = 6). Rat plasma samples ...

  14. Development and Validation of Reverse Phase High Performance ...

    African Journals Online (AJOL)

    Purpose: To develop a sensitive and validated reverse phase-high performance liquid chromatographic (RP-HPLC) method for quantification of olanzapine in micro-sample of rat plasma using UV detection. Methods: A single oral dose of olanzapine (7 mg/kg) was given to overnight fasted rats (n = 6). Rat plasma samples ...

  15. High Performance Computing at NASA

    Science.gov (United States)

    Bailey, David H.; Cooper, D. M. (Technical Monitor)

    1994-01-01

    The speaker will give an overview of high performance computing in the U.S. in general and within NASA in particular, including a description of the recently signed NASA-IBM cooperative agreement. The latest performance figures of various parallel systems on the NAS Parallel Benchmarks will be presented. The speaker was one of the authors of the NAS (National Aerospace Standards) Parallel Benchmarks, which are now widely cited in the industry as a measure of sustained performance on realistic high-end scientific applications. It will be shown that significant progress has been made by the highly parallel supercomputer industry during the past year or so, with several new systems, based on high-performance RISC processors, that now deliver superior performance per dollar compared to conventional supercomputers. Various pitfalls in reporting performance will be discussed. The speaker will then conclude by assessing the general state of the high performance computing field.

  16. INL High Performance Building Strategy

    Energy Technology Data Exchange (ETDEWEB)

    Jennifer D. Morton

    2010-02-01

    High performance buildings, also known as sustainable buildings and green buildings, are resource efficient structures that minimize the impact on the environment by using less energy and water, reduce solid waste and pollutants, and limit the depletion of natural resources while also providing a thermally and visually comfortable working environment that increases productivity for building occupants. As Idaho National Laboratory (INL) becomes the nation’s premier nuclear energy research laboratory, the physical infrastructure will be established to help accomplish this mission. This infrastructure, particularly the buildings, should incorporate high performance sustainable design features in order to be environmentally responsible and reflect an image of progressiveness and innovation to the public and prospective employees. Additionally, INL is a large consumer of energy that contributes to both carbon emissions and resource inefficiency. In the current climate of rising energy prices and political pressure for carbon reduction, this guide will help new construction project teams to design facilities that are sustainable and reduce energy costs, thereby reducing carbon emissions. With these concerns in mind, the recommendations described in the INL High Performance Building Strategy (previously called the INL Green Building Strategy) are intended to form the INL foundation for high performance building standards. This revised strategy incorporates the latest federal and DOE orders (Executive Order [EO] 13514, “Federal Leadership in Environmental, Energy, and Economic Performance” [2009], EO 13423, “Strengthening Federal Environmental, Energy, and Transportation Management” [2007], and DOE Order 430.2B, “Departmental Energy, Renewable Energy, and Transportation Management” [2008]), the latest guidelines, trends, and observations in high performance building construction, and the latest changes to the Leadership in Energy and Environmental Design

  17. High performance flexible heat pipes

    Science.gov (United States)

    Shaubach, R. M.; Gernert, N. J.

    1985-01-01

    A Phase I SBIR NASA program for developing and demonstrating high-performance flexible heat pipes for use in the thermal management of spacecraft is examined. The program combines several technologies such as flexible screen arteries and high-performance circumferential distribution wicks within an envelope which is flexible in the adiabatic heat transport zone. The first six months of work during which the Phase I contract goal were met, are described. Consideration is given to the heat-pipe performance requirements. A preliminary evaluation shows that the power requirement for Phase II of the program is 30.5 kilowatt meters at an operating temperature from 0 to 100 C.

  18. The High Performance Computing Initiative

    Science.gov (United States)

    Holcomb, Lee B.; Smith, Paul H.; Macdonald, Michael J.

    1991-01-01

    The paper discusses NASA High Performance Computing Initiative (HPCI), an essential component of the Federal High Performance Computing Program. The HPCI program is designed to provide a thousandfold increase in computing performance, and apply the technologies to NASA 'Grand Challenges'. The Grand Challenges chosen include integrated multidisciplinary simulations and design optimizations of aerospace vehicles throughout the mission profiles; the multidisciplinary modeling and data analysis of the earth and space science physical phenomena; and the spaceborne control of automated systems, handling, and analysis of sensor data and real-time response to sensor stimuli.

  19. Progress of the ITER NBI acceleration grid power supply reference design

    Energy Technology Data Exchange (ETDEWEB)

    Toigo, Vanni [Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, Corso Stati Uniti 4, I-35127 Padova (Italy); Zanotto, Loris, E-mail: loris.zanotto@igi.cnr.it [Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, Corso Stati Uniti 4, I-35127 Padova (Italy); Bigi, Marco [Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, Corso Stati Uniti 4, I-35127 Padova (Italy); Decamps, Hans [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France); Ferro, Alberto; Gaio, Elena [Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, Corso Stati Uniti 4, I-35127 Padova (Italy); Gutiérrez, Daniel [Fusion For Energy, C/Josep Pla 2, 08019 Barcelona (Spain); Tsuchida, Kazuki; Watanabe, Kazuhiro [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki-ken 311-0193 (Japan)

    2013-10-15

    Highlights: ► This paper reports the progress in the reference design of the Acceleration Grid Power Supply (AGPS) of the ITER Neutral Beam Injector (NBI) ► A critical revision of the main design choices is presented in light of the definition of some key interface parameters between the two AGPS subsystems. ► The verification of the fulfillment of the requirements in any operational conditions is reported and discussed. -- Abstract: This paper reports the progress in the reference design of the Acceleration Grid Power Supply (AGPS) of the ITER Neutral Beam Injector (NBI). The design of the AGPS is very challenging, as it shall be rated to provide about 55 MW at 1 MV dc in quasi steady-state conditions; moreover, the procurement of the system is shared between the European Domestic Agency (F4E) and the Japanese Domestic Agency (JADA), resulting in additional design complication due to the need of a common definition of the interface parameters. A critical revision of the main design choices is presented also in light of the definition of some key interface parameters between the two AGPS subsystems. Moreover, the verification of the fulfillment of the requirements in any operational conditions taking into account the tolerance of the different parameters is also reported and discussed.

  20. Development of a RF-driven ion source for the ITER NBI system

    Energy Technology Data Exchange (ETDEWEB)

    Staebler, A. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, 85748 Garching (Germany)], E-mail: albrecht.staebler@ipp.mpg.de; Fantz, U.; Franzen, P.; Berger, M.; Christ-Koch, S.; Falter, H.D.; Froeschle, M.; Gutser, R.; Heinemann, B.; Holtum, D.; Kraus, W.; Martens, C.; McNeely, P.; Nocentini, R.; Obermayer, S.; Riedl, R.; Speth, E.; Wuenderlich, D. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, 85748 Garching (Germany)

    2009-06-15

    Extensive R and D work on RF-driven negative hydrogen ion sources carried out at IPP Garching led to the decision of ITER to select this type of source as the new reference source for the ITER NBI system. The principle suitability of the RF source has been demonstrated in a small scale, short pulse length experiment: accelerated current densities, co-extracted electron currents at a source operation pressure, all well inside the range of the ITER requirements have been achieved simultaneously. In subsequent experiments, pulse lengths up to 1 h and the possibility of modularly extending the source to ITER source dimensions were demonstrated. The results achieved at the various IPP test beds, the lessons learnt during optimising the source for negative ion production and extraction as well as the problems still to be solved are summarized. As the next step in support of the NBI development for ITER, IPP plans to build a new test facility for beam extraction from a source of half the size for ITER.

  1. High-Performance Operating Systems

    DEFF Research Database (Denmark)

    Sharp, Robin

    1999-01-01

    Notes prepared for the DTU course 49421 "High Performance Operating Systems". The notes deal with quantitative and qualitative techniques for use in the design and evaluation of operating systems in computer systems for which performance is an important parameter, such as real-time applications......, communication systems and multimedia systems....

  2. High Performance Bulk Thermoelectric Materials

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Zhifeng [Boston College, Chestnut Hill, MA (United States)

    2013-03-31

    Over 13 plus years, we have carried out research on electron pairing symmetry of superconductors, growth and their field emission property studies on carbon nanotubes and semiconducting nanowires, high performance thermoelectric materials and other interesting materials. As a result of the research, we have published 104 papers, have educated six undergraduate students, twenty graduate students, nine postdocs, nine visitors, and one technician.

  3. High performance in software development

    CERN Multimedia

    CERN. Geneva; Haapio, Petri; Liukkonen, Juha-Matti

    2015-01-01

    What are the ingredients of high-performing software? Software development, especially for large high-performance systems, is one the most complex tasks mankind has ever tried. Technological change leads to huge opportunities but challenges our old ways of working. Processing large data sets, possibly in real time or with other tight computational constraints, requires an efficient solution architecture. Efficiency requirements span from the distributed storage and large-scale organization of computation and data onto the lowest level of processor and data bus behavior. Integrating performance behavior over these levels is especially important when the computation is resource-bounded, as it is in numerics: physical simulation, machine learning, estimation of statistical models, etc. For example, memory locality and utilization of vector processing are essential for harnessing the computing power of modern processor architectures due to the deep memory hierarchies of modern general-purpose computers. As a r...

  4. Neo4j high performance

    CERN Document Server

    Raj, Sonal

    2015-01-01

    If you are a professional or enthusiast who has a basic understanding of graphs or has basic knowledge of Neo4j operations, this is the book for you. Although it is targeted at an advanced user base, this book can be used by beginners as it touches upon the basics. So, if you are passionate about taming complex data with the help of graphs and building high performance applications, you will be able to get valuable insights from this book.

  5. High-performance sports medicine.

    Science.gov (United States)

    Speed, Cathy

    2013-02-01

    High performance sports medicine involves the medical care of athletes, who are extraordinary individuals and who are exposed to intensive physical and psychological stresses during training and competition. The physician has a broad remit and acts as a 'medical guardian' to optimise health while minimising risks. This review describes this interesting field of medicine, its unique challenges and priorities for the physician in delivering best healthcare.

  6. High Performance Tools And Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Collette, M R; Corey, I R; Johnson, J R

    2005-01-24

    This goal of this project was to evaluate the capability and limits of current scientific simulation development tools and technologies with specific focus on their suitability for use with the next generation of scientific parallel applications and High Performance Computing (HPC) platforms. The opinions expressed in this document are those of the authors, and reflect the authors' current understanding and functionality of the many tools investigated. As a deliverable for this effort, we are presenting this report describing our findings along with an associated spreadsheet outlining current capabilities and characteristics of leading and emerging tools in the high performance computing arena. This first chapter summarizes our findings (which are detailed in the other chapters) and presents our conclusions, remarks, and anticipations for the future. In the second chapter, we detail how various teams in our local high performance community utilize HPC tools and technologies, and mention some common concerns they have about them. In the third chapter, we review the platforms currently or potentially available to utilize these tools and technologies on to help in software development. Subsequent chapters attempt to provide an exhaustive overview of the available parallel software development tools and technologies, including their strong and weak points and future concerns. We categorize them as debuggers, memory checkers, performance analysis tools, communication libraries, data visualization programs, and other parallel development aides. The last chapter contains our closing information. Included with this paper at the end is a table of the discussed development tools and their operational environment.

  7. High-Performance Liquid Chromatographic Analysis of Duloxetine and Its Metabolites in Rat and Characterization of Metabolites in Plasma, Urine, Feces and Bile through Retro-Synthesis Followed By NMR and MS Study

    OpenAIRE

    T. K. Laha; G. Mishra; S. Sen

    2013-01-01

    A simple and sensitive reverse phase high performance liquid chromatographic (RP-HPLC) method for determination of duloxetine and twelve of its metabolites, Sulfate conjugate of 4-hydroxy duloxetine (M1), N-desmethyl duloxetine (M2), Glucuronide conjugate of 4-hydroxy duloxetine (M3), Glucuronide conjugate of 6-hydroxy duloxetine (M4), Glucuronide conjugate of 4,6-dihydroxy duloxetine (M5), Glucuronide conjugate of 5-hydroxy-6-methoxy duloxetine (M6), 4-Hydroxy duloxetine (M7), 5-Hydroxy dulo...

  8. Characterization of Alfvén eigenmodes using NBI during current ramp-up in the ASDEX Upgrade tokamak

    NARCIS (Netherlands)

    S da Graça,; Conway, G. D.; Lauber, P.; Curran, D.; Igochine, V.; Classen, I.G.J.; M. García-Muñoz,; Stober, J.; VanZeeland, M. A.; Manso, M. E.; ASDEX Upgrade team,

    2012-01-01

    Alfvén cascades (ACs) and beta-induced Alfvén eigenmodes (BAEs) have been studied in the ASDEX Upgrade tokamak during the current ramp-up phase of neutral beam heated (NBI) discharges using principally reflectometry, but also soft x-ray (SXR) and electron cyclotron emission imaging (ECEI). ACs have

  9. Development of a RF source for ITER NBI: First results with D{sup -} operation

    Energy Technology Data Exchange (ETDEWEB)

    Speth, E. [Max-Planck-Institut fuer Plasmaphysik, Postfach 1533, D-85740 Garching (Germany)]. E-mail: eckehart.speth@ipp.mpg.de; Falter, H.D. [Max-Planck-Institut fuer Plasmaphysik, Postfach 1533, D-85740 Garching (Germany); Franzen, P. [Max-Planck-Institut fuer Plasmaphysik, Postfach 1533, D-85740 Garching (Germany); Heinemann, B. [Max-Planck-Institut fuer Plasmaphysik, Postfach 1533, D-85740 Garching (Germany); Bandyopadhyay, M. [Max-Planck-Institut fuer Plasmaphysik, Postfach 1533, D-85740 Garching (Germany); Fantz, U. [Max-Planck-Institut fuer Plasmaphysik, Postfach 1533, D-85740 Garching (Germany); Kraus, W. [Max-Planck-Institut fuer Plasmaphysik, Postfach 1533, D-85740 Garching (Germany); McNeely, P. [Max-Planck-Institut fuer Plasmaphysik, Postfach 1533, D-85740 Garching (Germany); Riedl, R. [Max-Planck-Institut fuer Plasmaphysik, Postfach 1533, D-85740 Garching (Germany); Tanga, A. [Max-Planck-Institut fuer Plasmaphysik, Postfach 1533, D-85740 Garching (Germany); Wilhelm, R. [Max-Planck-Institut fuer Plasmaphysik, Postfach 1533, D-85740 Garching (Germany)

    2005-11-15

    As an alternative for ITER NBI a RF source is being developed at IPP, Garching. This paper reports the first results with deuterium extracted from a restricted extraction area and accelerated to about 22 KeV. A current density of 150 A/m{sup 2} (calorimetric) of D{sup -} ions has been reached so far in a Cs-seeded discharge with an electron/ion ration of {<=}1. The effect of the magnetic filter field on the yield and the electron suppression and possible limitations/improvements are discussed. The neutron production rate is about a factor 40 lower than expected from positive ions. Possible reasons for this are discussed.

  10. Effect of disease state on ionization during bioanalysis of MK-7009, a selective HCV NS3/NS4 protease inhibitor, in human plasma and human Tween-treated urine by high-performance liquid chromatography with tandem mass spectrometric detection.

    Science.gov (United States)

    Anderson, M D G; Breidinger, S A; Woolf, E J

    2009-04-15

    HPLC-MS/MS methods for the determination of a Hepatitis C NS3/NS4 protease inhibitor (MK-7009) in human plasma and Tween-treated urine were developed and validated over the concentration range 1-1000 ng/mL and 0.2-100 microg/mL respectively. A stable isotope labeled internal standard (ISTD), D(4)-MK-7009, was employed. Analytes were chromatographed by reversed phase HPLC and quantified by an MS/MS system. Electrospray ionization in the positive mode was employed. Multiple reaction monitoring of the precursor to product ion pairs m/z 758.6-->637.4 MK-7009 and m/z 762.5-->637.4 ISTD was used for quantitation. Analyte and internal standard were extracted from 250 microL of plasma using an automated 96-well liquid-liquid extraction. Plasma pH adjustment prior to extraction minimized ionization suppression in plasma samples from patients with Hepatitis C. The urine method involved direct dilution in the 96-well format of 0.020 mL Tween-treated urine. These methods have supported several clinical studies. Incurred plasma sample reanalysis demonstrated adequate assay reproducibility and ruggedness.

  11. Narrow-band imaging (NBI for improving the assessment of vocal fold leukoplakia and overcoming the umbrella effect.

    Directory of Open Access Journals (Sweden)

    H Klimza

    Full Text Available It is crucial to find a balance between functional and oncological outcome when choosing an adequate method for the management of vocal fold leukoplakia. Therefore, a detailed examination is a milestone in the decision-making process.To examine whether narrow-band imaging (NBI can be helpful in vocal fold assessment in the case of leukoplakia and how to overcome the "umbrella effect"- understood as the submucosal vascular pattern hidden under the plaque.Prospective cohort of 41 consecutive patients. Inclusion criteria: vocal fold leukoplakia, no previous procedures (surgery, radiotherapy, and preoperative endoscopy with an optical filter for NBI. Two groups: "suspicious" and "normal", according to the submucosal microvascular pattern of peripheral regions of the mucosa surrounding the plaque, were distinguished. Patients were qualified for a full-thickness or partial-thickness biopsy, respectively. Criteria defining suspected characters were well-demarcated brownish areas with scattered brown spots corresponding to type IV, Va, Vb, and Vc NI classifications.In 22/41 (53.7% patients with "suspected" microvascular pattern, full-thickness biopsy was performed. Moderate and severe dysplasia was revealed in 15 type IV and 7 type Va NI patients. In 19/41 (46.3% patients with proper NBI vessel pattern treated by partial-thickness biopsy, hyperkeratosis was diagnosed. There was a strong correlation between the NBI pattern and final histology: Chi2 (2 = 41.0 (p = 0.0000.The results demonstrate that NBI endoscopic assessment of the submucosal microvascular pattern of mucosa surrounding the plaque can be an effective method to categorise the risk in vocal fold leukoplakia prior to treatment.

  12. Narrow-band imaging (NBI) for improving the assessment of vocal fold leukoplakia and overcoming the umbrella effect

    Science.gov (United States)

    Tokarski, M.; Piersiala, K.; Wierzbicka, M.

    2017-01-01

    Background It is crucial to find a balance between functional and oncological outcome when choosing an adequate method for the management of vocal fold leukoplakia. Therefore, a detailed examination is a milestone in the decision-making process. Aim To examine whether narrow-band imaging (NBI) can be helpful in vocal fold assessment in the case of leukoplakia and how to overcome the “umbrella effect”- understood as the submucosal vascular pattern hidden under the plaque. Material and methods Prospective cohort of 41 consecutive patients. Inclusion criteria: vocal fold leukoplakia, no previous procedures (surgery, radiotherapy), and preoperative endoscopy with an optical filter for NBI. Two groups: “suspicious” and “normal”, according to the submucosal microvascular pattern of peripheral regions of the mucosa surrounding the plaque, were distinguished. Patients were qualified for a full-thickness or partial-thickness biopsy, respectively. Criteria defining suspected characters were well-demarcated brownish areas with scattered brown spots corresponding to type IV, Va, Vb, and Vc NI classifications. Results In 22/41 (53.7%) patients with “suspected” microvascular pattern, full-thickness biopsy was performed. Moderate and severe dysplasia was revealed in 15 type IV and 7 type Va NI patients. In 19/41 (46.3%) patients with proper NBI vessel pattern treated by partial-thickness biopsy, hyperkeratosis was diagnosed. There was a strong correlation between the NBI pattern and final histology: Chi2 (2) = 41.0 (p = 0.0000). Conclusion The results demonstrate that NBI endoscopic assessment of the submucosal microvascular pattern of mucosa surrounding the plaque can be an effective method to categorise the risk in vocal fold leukoplakia prior to treatment. PMID:28662209

  13. High-performing physician executives.

    Science.gov (United States)

    Brown, M; Larson, S R; McCool, B P

    1988-01-01

    Physician leadership extends beyond traditional clinical disciplines to hospital administration, group practice management, health policy making, management of managed care programs, and many business positions. What kind of person makes a good physician executive? What stands out as the most important motivations, attributes, and interests of high-performing physician executives? How does this compare with non-physician health care executives? Such questions have long been high on the agenda of executives in other industries. This article builds on existing formal assessments of leadership attributes of high-performing business, government, and educational executives and on closer examination of health care executives. Previous studies looked at the need for innovative, entrepreneurial, energetic, community-oriented leaders for positions throughout health care. Traits that distinguish excellence and leadership were described by Brown and McCool.* That study characterized successful leaders in terms of physical strengths (high energy, good health, and propensity for hard work), mental strengths (creativity, intuition, and innovation), and organizational strengths (mission orientation, vision, and entrepreneurial spirit). In this investigation, a subset of health care executives, including physician executives, was examined more closely. It was initially assumed that successful physician executives exhibit many of the same positive traits as do nonphysician executives. This assumption was tested with physician leaders in a range of administrative and managerial positions. We also set out to identify key differences between physician and nonphysician executives. Even with our limited exploration, it seems to us that physician executives probably do differ from nonphysician executives.

  14. Report on three aliphatic dimethylarsinoyl compounds as common minor constituents in marine samples. An investigation using high-performance liquid chromatography inductively coupled plasma mass spectrometry and electrospray ionisation tandem mass spectrometry

    DEFF Research Database (Denmark)

    Sloth, Jens Jørgen; Larsen, Erik Huusfeldt; Julshamn, K.

    2005-01-01

    Three water-soluble aliphatic arsenicals, dimethylarsinoyl acetate (DMAA), dimethylarsinoyl ethanol (DMAE), and dimethylarsinoyl propionate (DMAP), were identified in marine biological samples. Sample extracts in methanol/water (1 + 1) were analysed by cation-exchange high-performance liquid...... for the structures of the three compounds. The concentrations of the three arsenicals were determined in 37 marine organisms comprising algae, crustaceans, bivalves, fish and mammals by HPLC/ICPMS. The three arsenicals DMAA, DMAE and DMAP, which occurred at mug kg(-1) concentrations, were detected in 25, 23 and 17...

  15. Development of a hydrophilic liquid interaction chromatography-high-performance liquid chromatography-tandem mass spectrometry based stable isotope dilution analysis and pharmacokinetic studies on bioactive pyridines in human plasma and urine after coffee consumption.

    Science.gov (United States)

    Lang, Roman; Wahl, Anika; Skurk, Thomas; Yagar, Erkan Firat; Schmiech, Ludger; Eggers, Rudolf; Hauner, Hans; Hofmann, Thomas

    2010-02-15

    The paper reports on the development of an accurate hydrophilic liquid interaction chromatography tandem mass spectrometry (HILIC-MS/MS) based stable isotope dilution analysis for the simultaneous quantitation of the food-derived bioactive pyridines trigonelline, nicotinic acid, nicotinamide, and N-methylpyridinium, as well as their key metabolites nicotinamide-N-oxide, N-methylnicotinamide, N-methyl-2-pyridone-5-carboxamide, N-methyl-4-pyridone-5-carboxamide, and N-methyl-2-pyridone-5-carboxylic acid in human plasma and urine. Precision of the stable isotope dilution analysis (SIDA) was 1.9% and 11.9% relative standard deviation (n = 6), and accuracy was between 92.4% and 113.0%. The lower limit of quantitation (LLOQ) was 50 fmol (10 pmol/mL) injected onto the column for all analytes with the exception of N-methyl-2-pyridone-5-carboxylic acid and N-methyl-2-pyridone-5-carboxamide, for which an LLOQ of 100 fmol (20 pmol/mL) was found. The method was applied to monitor the plasma appearance and urinary excretion and to determine pharmacokinetic parameters of the bioactive pyridines as well as their metabolites in a clinical human intervention study with healthy volunteers (six women, seven men) after oral administration of 350 mL of a standard coffee beverage. Trigonelline plasma levels increased from 160 nmol/L to maximum concentrations of 5479 (males) or 6547 nmol/L (females), and N-methylpyridinium plasma levels raised from virtually complete absence to maximum values of 777 (females) or 804 nmol/L (males) within 2-3 and 1-2 h after coffee consumption, respectively. The high plasma levels of N-methylpyridinium found after coffee consumption clearly demonstrate for the first time that this cation is entering the vascular system, which is the prerequisite for biological in vivo effects claimed for that compound. In contrast, the coffee intervention did not significantly influence the plasma concentrations of N-methyl-2-pyridone-5-carboxamide and N-methyl-4-pyridone

  16. High Performance Flexible Thermal Link

    Science.gov (United States)

    Sauer, Arne; Preller, Fabian

    2014-06-01

    The paper deals with the design and performance verification of a high performance and flexible carbon fibre thermal link.Project goal was to design a space qualified thermal link combining low mass, flexibility and high thermal conductivity with new approaches regarding selected materials and processes. The idea was to combine the advantages of existing metallic links regarding flexibility and the thermal performance of high conductive carbon pitch fibres. Special focus is laid on the thermal performance improvement of matrix systems by means of nano-scaled carbon materials in order to improve the thermal performance also perpendicular to the direction of the unidirectional fibres.One of the main challenges was to establish a manufacturing process which allows handling the stiff and brittle fibres, applying the matrix and performing the implementation into an interface component using unconventional process steps like thermal bonding of fibres after metallisation.This research was funded by the German Federal Ministry for Economic Affairs and Energy (BMWi).

  17. High Performance Perovskite Solar Cells

    Science.gov (United States)

    Tong, Xin; Lin, Feng; Wu, Jiang

    2015-01-01

    Perovskite solar cells fabricated from organometal halide light harvesters have captured significant attention due to their tremendously low device costs as well as unprecedented rapid progress on power conversion efficiency (PCE). A certified PCE of 20.1% was achieved in late 2014 following the first study of long‐term stable all‐solid‐state perovskite solar cell with a PCE of 9.7% in 2012, showing their promising potential towards future cost‐effective and high performance solar cells. Here, notable achievements of primary device configuration involving perovskite layer, hole‐transporting materials (HTMs) and electron‐transporting materials (ETMs) are reviewed. Numerous strategies for enhancing photovoltaic parameters of perovskite solar cells, including morphology and crystallization control of perovskite layer, HTMs design and ETMs modifications are discussed in detail. In addition, perovskite solar cells outside of HTMs and ETMs are mentioned as well, providing guidelines for further simplification of device processing and hence cost reduction. PMID:27774402

  18. High Performance Perovskite Solar Cells.

    Science.gov (United States)

    Tong, Xin; Lin, Feng; Wu, Jiang; Wang, Zhiming M

    2016-05-01

    Perovskite solar cells fabricated from organometal halide light harvesters have captured significant attention due to their tremendously low device costs as well as unprecedented rapid progress on power conversion efficiency (PCE). A certified PCE of 20.1% was achieved in late 2014 following the first study of long-term stable all-solid-state perovskite solar cell with a PCE of 9.7% in 2012, showing their promising potential towards future cost-effective and high performance solar cells. Here, notable achievements of primary device configuration involving perovskite layer, hole-transporting materials (HTMs) and electron-transporting materials (ETMs) are reviewed. Numerous strategies for enhancing photovoltaic parameters of perovskite solar cells, including morphology and crystallization control of perovskite layer, HTMs design and ETMs modifications are discussed in detail. In addition, perovskite solar cells outside of HTMs and ETMs are mentioned as well, providing guidelines for further simplification of device processing and hence cost reduction.

  19. High Performance Proactive Digital Forensics

    Science.gov (United States)

    Alharbi, Soltan; Moa, Belaid; Weber-Jahnke, Jens; Traore, Issa

    2012-10-01

    With the increase in the number of digital crimes and in their sophistication, High Performance Computing (HPC) is becoming a must in Digital Forensics (DF). According to the FBI annual report, the size of data processed during the 2010 fiscal year reached 3,086 TB (compared to 2,334 TB in 2009) and the number of agencies that requested Regional Computer Forensics Laboratory assistance increasing from 689 in 2009 to 722 in 2010. Since most investigation tools are both I/O and CPU bound, the next-generation DF tools are required to be distributed and offer HPC capabilities. The need for HPC is even more evident in investigating crimes on clouds or when proactive DF analysis and on-site investigation, requiring semi-real time processing, are performed. Although overcoming the performance challenge is a major goal in DF, as far as we know, there is almost no research on HPC-DF except for few papers. As such, in this work, we extend our work on the need of a proactive system and present a high performance automated proactive digital forensic system. The most expensive phase of the system, namely proactive analysis and detection, uses a parallel extension of the iterative z algorithm. It also implements new parallel information-based outlier detection algorithms to proactively and forensically handle suspicious activities. To analyse a large number of targets and events and continuously do so (to capture the dynamics of the system), we rely on a multi-resolution approach to explore the digital forensic space. Data set from the Honeynet Forensic Challenge in 2001 is used to evaluate the system from DF and HPC perspectives.

  20. Simultaneous determination of corosolic acid and euscaphic acid in the plasma of normal and diabetic rat after oral administration of extract of Potentilla discolor Bunge by high-performance liquid chromatography/electrospray ionization mass spectrometry.

    Science.gov (United States)

    Li, Jing-jing; Li, Yi; Bai, Min; Tan, Jing-fu; Wang, Qiang; Yang, Jie

    2014-05-01

    Potentilla discolor Bunge has been used for diabetes in China for a long time. Corosolic acid (CA) and euscaphic acid (EA), with significant anti-diabetic activity, are two major triterpenoids in P. discolor. In this study, a specific, sensitive and convenient LC-MS method has been developed for simultaneous determination of CA and EA in the plasma of normal and diabetic rats after oral administration of the extract of P. discolor. The chromatographic separation was achieved using an Alltima C18 column (53 × 7.0 mm, i.d., 3 µm) with a mobile phase composed of 0.1% formic acid water and 0.1% formic acid acetonitrile at a flow rate of 1.0 mL/min. The detection was performed by MS with electrospray ionization interface in negative selected ion monitoring mode. All the validation data, such as specificity, linearity (r(2)  > 0.9991 within 0.025-10.0 µg/mL), lower limit of quantitation (2.5 ng/mL), precision (intra- and inter-day <14.7%), accuracy (<15.0%), recovery (85.7-110.8%) and stability were determined and all of them were within the required limits. This method was successfully applied for the evaluation of the pharmacokinetic behaviors of these two compounds in the plasma of normal and diabetic rats. Copyright © 2013 John Wiley & Sons, Ltd.

  1. Simultaneous Quantification of Diazepam and Dexamethasone in Plasma by High-Performance Liquid Chromatography with Tandem Mass Spectrometry and Its Application to a Pharmacokinetic Comparison between Normoxic and Hypoxic Rats.

    Science.gov (United States)

    Gong, Wenwen; Liu, Shuhong; Xu, Pingxiang; Fan, Ming; Xue, Ming

    2015-04-16

    In order to investigate the pharmacokinetics of a combination of diazepam and dexamethasone under hypoxic conditions, a novel, sensitive and specific liquid chromatography with tandem mass spectrometry (LC-MS/MS) method for the simultaneous determination of diazepam and dexamethasone in rat plasma was developed and validated. The chromatographic separation of analytes was successfully achieved on an XTerra® MS C18 column using a gradient elution of methanol and water containing 0.1% formic acid at a flow rate of 0.5 mL/min. This method demonstrated good linearity and no endogenous material interferences. The linear ranges were 1.0-100 ng/mL for diazepam and 2.0-200 ng/mL for dexamethasone. The intra- and inter-day precision for the two compounds in plasma were lower than 10.0%, and the accuracy was between -7.9% and 11.5%. Our method was then successfully applied in a pharmacokinetic comparison between normoxic and hypoxic rats. The results indicated that there were significant differences in the main pharmacokinetics parameters of diazepam and dexamethasone between normoxic and hypoxic rats. The results provide the important and valuable information for discovering and developing novel anti-hypoxia drug combinations, as well as a better understanding of the safety and efficacy of these drugs.

  2. Simultaneous determination of 8 HIV protease inhibitors in human plasma by isocratic high-performance liquid chromatography with combined use of UV and fluorescence detection: amprenavir, indinavir, atazanavir, ritonavir, lopinavir, saquinavir, nelfinavir and M8-nelfinavir metabolite.

    Science.gov (United States)

    Verbesselt, R; Van Wijngaerden, E; de Hoon, J

    2007-01-01

    A simple, accurate and fast method was developed for determination of the commonly used HIV protease inhibitors (PIs) amprenavir, indinavir, atazanavir, ritonavir, lopinavir, nelfinavir, M8-nelfinavir metabolite and saquinavir in human plasma. Liquid-liquid extraction was used with hexane/ethylacetate from buffered plasma samples with a borate buffer pH 9.0. Isocratic chromatographic separation of all components was performed on an Allsphere hexyl HPLC column with combined UV and fluorescence detection. Calibration curves were constructed in the range of 0.025-10 mg/l. Accuracy and precision of the standards were all below 15% and the lowest limit of quantitation was 0.025 mg/l. Stability of quality control samples at different temperature conditions was found to be below 20% of nominal values. The advantages of this method are: (1) inclusion and determination of the newly approved atazanavir, (2) simultaneous isocratic HPLC separation of all compounds and (3) increased specificity and sensitivity for amprenavir by using fluorescence detection. This method can be used for therapeutic drug monitoring of all PIs currently commercialised and is now part of current clinical practice.

  3. Sensitive high performance liquid chromatographic method for the ...

    African Journals Online (AJOL)

    A new simple, sensitive, cost-effective and reproducible high performance liquid chromatographic (HPLC) method for the determination of proguanil (PG) and its metabolites, cycloguanil (CG) and 4-chlorophenylbiguanide (4-CPB) in urine and plasma is described. The extraction procedure is a simple three-step process ...

  4. Ultra high performance liquid chromatography/tandem mass spectrometry based identification of steroid esters in serum and plasma: an efficient strategy to detect natural steroids abuse in breeding and racing animals.

    Science.gov (United States)

    Kaabia, Z; Dervilly-Pinel, G; Hanganu, F; Cesbron, N; Bichon, E; Popot, M A; Bonnaire, Y; Le Bizec, B

    2013-04-05

    During last decades, the use of natural steroids in racing and food producing animals for doping purposes has been flourishing. The endogenous or exogenous origin of these naturally occurring steroids has since remained a challenge for the different anti-doping laboratories. The administration of these substances to animals is usually made through an intra-muscular pathway with the steroid under its ester form for a higher bioavailability and a longer lasting effect. Detecting these steroid esters would provide an unequivocal proof of an exogenous administration of the considered naturally occurring steroids. A quick analytical method able to detect at trace level (below 50 pg/mL) a large panel of more than 20 steroid esters in serum and plasma potentially used for doping purposes in bovine and equine has been developed. Following a pre-treatment step, the sample is submitted to a solid phase extraction (SPE) before analysis with UPLC-MS/MS. The analytical method's efficiency has been probed through three different in vivo experiments involving testosterone propionate intra-muscular administration to three heifers, 17-estradiol benzoate intra-muscular administration to a bull and a heifer and nandrolone laurate intra-muscular administration to a stallion. The results enabled detecting the injected testosterone propionate and 17-estradiol benzoate 2 and 17 days, respectively, post-administration in bovine and nandrolone laurate up to 14 days post-administration in equine. The corresponding elimination profiles in bovine serum and equine plasma have been established. The first bovine experiment exhibited a maximal testosterone propionate concentration of 400 pg/mL in one of the three heifer serum within 5h post-administration. The second bovine experiment reported a maximal 17-estradiol benzoate concentration of 480 pg/mL in the same matrix recorded 9 days after its administration. The last equine experiment resulted in a maximal nandrolone laurate concentration of

  5. Sensitive chiral high-performance liquid chromatographic determination of anthelmintic flubendazole and its phase I metabolites in blood plasma using UV photodiode-array and fluorescence detection Application to pharmacokinetic studies in sheep.

    Science.gov (United States)

    Nobilis, Milan; Vybíralová, Zuzana; Krízová, Veronika; Kubícek, Vladimír; Soukupová, Marie; Lamka, Jirí; Szotáková, Barbora; Skálová, Lenka

    2008-12-01

    Although benzimidazole anthelmintic flubendazole, methyl ester of [5-(4-fluorobenzoyl)-1H-benzimidazol-2-yl]carbamic acid, is extensively used in veterinary and human medicine for the treatment of gastrointestinal parasitic helminth infections, reliable data about its pharmacokinetics in various species have not been reported. Our previous work [M. Nobilis, Th. Jira, M. Lísa, M. Holcapek, B. Szotáková, J. Lamka, L.Skálová, J. Chromatogr. A 1149 (2007) 112-120] had described the stereospecificity of carbonyl reduction during phase I metabolic experiments in vitro. For in vivo pharmacokinetic studies, further improvement and optimization of bioanalytical HPLC method in terms of sensitivity and selectivity was necessary. Hence, a modified chiral bioanalytical HPLC method involving both UV photodiode-array and fluorescence detection for the determination of flubendazole, both enantiomers of reduced flubendazole and hydrolyzed flubendazole in the extracts from plasma samples was tested and validated. Albendazole was used as an internal standard. Sample preparation process involved a pH-dependent extraction of the analytes from the blood plasma into tert-butylmethyl ether. Chromatographic separations were performed on a Chiralcel OD-R 250 mm x 4.6mm column with mobile phase methanol-1M NaClO(4) (75:25, v/v) at the flow rate 0.5 ml min(-1). In quantitation, selective UV absorption maxima of 290 nm (for reduced flubendazole), 295 nm (for albendazole), 310 nm (for flubendazole) and 330 nm (for hydrolyzed flubendazole) were used in the UV photodiode-array detection, and lambda(exc.)/lambda(emis.)=228 nm/310 nm (for reduced flubendazole) and lambda(exc.)/lambda(emis.)=236 nm/346 nm (for albendazole) were set on the fluorescence detector. The fluorescence detection was approximately 10-times more sensitive than the UV detection. Each HPLC run lasted 27 min. The validated chiral HPLC-PDA-FL method was employed in the pharmacokinetic studies of flubendazole in sheep. The

  6. Simultaneous measurement of testosterone, androstenedione and dehydroepiandrosterone (DHEA) in serum and plasma using Isotope-Dilution 2-Dimension Ultra High Performance Liquid-Chromatography Tandem Mass Spectrometry (ID-LC-MS/MS).

    Science.gov (United States)

    Büttler, Rahel M; Martens, Frans; Kushnir, Mark M; Ackermans, Mariette T; Blankenstein, Marinus A; Heijboer, Annemieke C

    2015-01-01

    The adrenal and gonadal androgens, testosterone, androstenedione and dehydroepiandrosterone (DHEA) play an important role in sexual development as well as in other processes. We developed a method for simultaneous quantitative analysis of serum and plasma testosterone, androstenedione and DHEA levels using Isotope-Dilution Liquid-Chromatography Tandem Mass Spectrometry (ID-LC-MS/MS). Samples underwent liquid-liquid extraction and were analyzed on an Acquity 2D-UPLC-System and a Xevo TQ-S tandem mass spectrometer (Waters). The intra-assay and inter-assay coefficients of variation were DHEA, respectively. Inter-assay CVs at the lower limit were 10.6%, 16.9% and 9.0% for testosterone (0.10nmol/L), androstenedione (0.10nmol/L) and DHEA (1.0nmol/L), respectively. Recoveries of spiked analytes were 93-107%. The present testosterone method compared well (y=1.00x-0.04; r=0.998) to a published ID-LC-MS/MS method for testosterone in our lab. The latter method being concordant with a published reference method (Bui et al., 2013). The present method compared well to a published ID-LC-MS/MS method (Kushnir et al., 2010) (y=1.06x-0.06; r=0.996 for testosterone; y=1.04x-0.04; r=0.995 for androstenedione and y=1.03x+0.01; r=0.991 for DHEA). In conclusion, we developed a sensitive and accurate ID-LC-MS/MS method to simultaneously measure serum testosterone, androstenedione and DHEA in serum and plasma. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. A Validated High-Performance Liquid Chromatography-Tandem Mass Spectrometric (Lc-Ms/Ms Method for Simultaneous Determination of R(+-Ketorolac and S(−-Ketorolac in Human Plasma and Its Application to a Bioequivalence Study

    Directory of Open Access Journals (Sweden)

    Sabyasachi Patri

    2011-01-01

    Full Text Available We report a selective, accurate, and reproducible liquid chromatography-tandem mass spectrometric (LC-MS/MS method that employs solid phase extraction for quantification of ketorolac enantiomers in human plasma. Resolution of R(+-ketorolac and S(−-ketorolac was achieved using a Chiral-AGP column and a mobile phase of ammonium formate buffer (10 mM, pH 4.70±0.05:acetonitrile (85 : 15, v/v and 70 : 30, v/v in a gradient time program. S(+-etodolac was used as the internal standard (IS. Quantification was achieved using a positive electrospray ionization (ESI+ interface under multiple reaction monitoring (MRM condition. The method was validated over the concentration range of 9.36–1198.69 ng/ml for R(+-ketorolac and 6.07–776.74 ng/ml for S(−-ketorolac. Matrix effect was found negligible and the method showed good performances in terms of accuracy (89.6–102.7% and precision (1.7–6.7% for both enantiomers. Extraction recoveries of R(+-ketorolac, S(−-ketorolac, and S(+-etodolac were 82.04, 70.94, and 93.90%, respectively. Results of all stability exercises in human plasma were within acceptable limits. The method was successfully applied to a single dose cross over bioequivalence study in healthy human male volunteers. Incurred Sample Reanalysis (ISR was performed by randomly selecting 10% of total subject samples of the study using Statistical Analysis Software (SAS. Values of 91.1% for R (+-ketorolac and 83.5% for S(−-ketorolac indicated good acceptance for ISR.

  8. High performance liquid chromatography using UV detection for the simultaneous quantification of the new non-nucleoside reverse transcriptase inhibitor etravirine (TMC-125), and 4 protease inhibitors in human plasma.

    Science.gov (United States)

    Hirano, Atsushi; Takahashi, Masaaki; Kinoshita, Eri; Shibata, Masaaki; Nomura, Toshiharu; Yokomaku, Yoshiyuki; Hamaguchi, Motohiro; Sugiura, Wataru

    2010-01-01

    Etravirine (TMC-125, ETV) is a second-generation non-nucleoside reverse transcriptase inhibitor (NNRTI) that demonstrates potent activity against NNRTI-resistant strains of human immunodeficiency virus type-1 (HIV-1). Thus, ETV has been used in combination with ritonavir-boosted protease inhibitor (PI) and integrase inhibitor for therapy-experienced HIV-1-infected patients. On the other hand, as ETV is a substrate and inducer of cytochrome P450 3A4 (CYP3A4), ETV may induce metabolism of PI and alter the concentrations of co-administered PIs. In order to ensure optimal drug efficacy and prevention of resistance, it is essential to monitor plasma concentrations of ETV and PIs. Here we describe the application of HPLC with UV detection for the simulataneous assay of ETV and 4 PIs, darunavir (DRV), atazanavir (ATV), ritonavir (RTV) and lopinavir (LPV). In this study, the calibration curve of each drug was linear with the average accuracy ranging from 93.6 to 110.9%. Both intra- and interday coefficients of variation for each drug were less than 11.6%. The mean recovery of all drugs ranged from 88.0 to 97.5%. The limit of quantification was 0.04, 0.04, 0.04, 0.05 and 0.07 microg/ml for ETV, DRV, ATV, RTV and LPV, respectively. These results demonstrate that our HPLC-UV method can be used for routine determination of plasma concentrations of ETV and 4 PIs in clinical settings.

  9. The Role of NBI HDTV Magnifying Endoscopy in the Prehistologic Diagnosis of Laryngeal Papillomatosis and Spinocellular Cancer

    Directory of Open Access Journals (Sweden)

    Petr Lukes

    2014-01-01

    Full Text Available Narrow band imaging (NBI HDTV (high definition television magnifying endoscopy is considered to be superior for the accurate display of the microvascular patterns of superficial mucosal lesions. Observation of changes in intraepithelial papillary capillary loops (IPCL can help distinguish benign from malignant lesions as part of an “optical biopsy.” However, IPCL changes in papillomas may be mistaken for spinocellular cancer (SCC. The aim of the study was to determine whether observing microvascular changes alone is sufficient for discriminating between laryngeal SCC and papillomatosis. An additional aim was to identify associated characteristics that could clarify the diagnosis. The study included 109 patients with a suspected laryngeal tumor or papilloma. HDTV NBI magnifying endoscopy was performed during direct laryngoscopy. It was possible to visualize IPCL changes in 82 out of 109 patients (75.2%. In 71 (86.6% patients, the diagnosis was correctly determined. In 4 (4.9% cases, the diagnosis of SCC was expressed on the basis of finding pathologic IPCL, but histology did not demonstrate malignancy. To achieve a correct diagnosis using HDTV NBI magnifying endoscopy, it is important not only to observe changes in the shape of IPCL but also to note possible papillary structures with central-axis capillaries typical of papillomatosis.

  10. The role of NBI HDTV magnifying endoscopy in the prehistologic diagnosis of laryngeal papillomatosis and spinocellular cancer.

    Science.gov (United States)

    Lukes, Petr; Zabrodsky, Michal; Lukesova, Eva; Chovanec, Martin; Astl, Jaromir; Betka, Jaroslav A; Plzak, Jan

    2014-01-01

    Narrow band imaging (NBI) HDTV (high definition television) magnifying endoscopy is considered to be superior for the accurate display of the microvascular patterns of superficial mucosal lesions. Observation of changes in intraepithelial papillary capillary loops (IPCL) can help distinguish benign from malignant lesions as part of an "optical biopsy." However, IPCL changes in papillomas may be mistaken for spinocellular cancer (SCC). The aim of the study was to determine whether observing microvascular changes alone is sufficient for discriminating between laryngeal SCC and papillomatosis. An additional aim was to identify associated characteristics that could clarify the diagnosis. The study included 109 patients with a suspected laryngeal tumor or papilloma. HDTV NBI magnifying endoscopy was performed during direct laryngoscopy. It was possible to visualize IPCL changes in 82 out of 109 patients (75.2%). In 71 (86.6%) patients, the diagnosis was correctly determined. In 4 (4.9%) cases, the diagnosis of SCC was expressed on the basis of finding pathologic IPCL, but histology did not demonstrate malignancy. To achieve a correct diagnosis using HDTV NBI magnifying endoscopy, it is important not only to observe changes in the shape of IPCL but also to note possible papillary structures with central-axis capillaries typical of papillomatosis.

  11. Development and validation of a high-performance liquid chromatography-tandem mass spectrometry method for the simultaneous determination of irinotecan and its main metabolites in human plasma and its application in a clinical pharmacokinetic study.

    Directory of Open Access Journals (Sweden)

    Elena Marangon

    Full Text Available Irinotecan is currently used in several cancer regimens mainly in colorectal cancer (CRC. This drug has a narrow therapeutic range and treatment can lead to side effects, mainly neutropenia and diarrhea, frequently requiring discontinuing or lowering the drug dose. A wide inter-individual variability in irinotecan pharmacokinetic parameters and pharmacodynamics has been reported and associated to patients' genetic background. In particular, a polymorphism in the UGT1A1 gene (UGT1A1*28 has been linked to an impaired detoxification of SN-38 (irinotecan active metabolite to SN-38 glucuronide (SN-38G leading to increased toxicities. Therefore, therapeutic drug monitoring of irinotecan, SN-38 and SN-38G is recommended to personalize therapy. In order to quantify simultaneously irinotecan and its main metabolites in patients' plasma, we developed and validated a new, sensitive and specific HPLC-MS/MS method applicable to all irinotecan dosages used in clinic. This method required a small plasma volume, addition of camptothecin as internal standard and simple protein precipitation. Chromatographic separation was done on a Gemini C18 column (3 μM, 100 mm x 2.0 mm using 0.1% acetic acid/bidistilled water and 0.1% acetic acid/acetonitrile as mobile phases. The mass spectrometer worked with electrospray ionization in positive ion mode and selected reaction monitoring. The standard curves were linear (R2 ≥0.9962 over the concentration ranges (10-10000 ng/mL for irinotecan, 1-500 ng/mL for SN-38 and SN-38G and 1-5000 ng/mL for APC and had good back-calculated accuracy and precision. The intra- and inter-day precision and accuracy, determined on three quality control levels for all the analytes, were always <12.3% and between 89.4% and 113.0%, respectively. Moreover, we evaluated this bioanalytical method by re-analysis of incurred samples as an additional measure of assay reproducibility. This method was successfully applied to a pharmacokinetic study in

  12. Indoor Air Quality in High Performance Schools

    Science.gov (United States)

    High performance schools are facilities that improve the learning environment while saving energy, resources, and money. The key is understanding the lifetime value of high performance schools and effectively managing priorities, time, and budget.

  13. Rapid, high performance method for the determination of vitamin K(1), menaquinone-4 and vitamin K(1) 2,3-epoxide in human serum and plasma using liquid chromatography-hybrid quadrupole linear ion trap mass spectrometry.

    Science.gov (United States)

    Gentili, Alessandra; Cafolla, Arturo; Gasperi, Tecla; Bellante, Simona; Caretti, Fulvia; Curini, Roberta; Fernández, Virginia Pérez

    2014-04-18

    Unlike the other fat-soluble vitamins, vitamin K circulates in the human bloodstream at very low levels because of a low intake in the diet. Mammals have developed an efficient recycling system, known as vitamin K-epoxide cycle, which involve quinone, hydroquinone and epoxide forms of the vitamin. Phylloquinone (K(1)) is the main homologue, while menaquinone-4 (MK-4) is both a member of the vitamin K(2) family and metabolite of K(1) in extra-hepatic tissues. Notwithstanding the recent advances, many aspects of the complex vitamin K physiology still remain to be investigated. Therefore, there is a critical need to develop more reliable analytical methods for determining the vitamin K and its metabolites in biological fluids and tissues. Nevertheless, relatively low concentrations, unavailability of some authentic standards and occurrence of interfering lipids make this a challenging task. The method proposed in the present paper can directly and accurately estimate K(1), K(1) 2,3-epoxide (K(1)O), and MK-4 in human serum and plasma at concentrations in the ng/L-μg/L range, using labelled internal standards and a quadrupole linear ion trap instrument operated in multiple reaction monitoring (MRM) mode. High sensitivity was achieved by removing signal "endogenous suppressors" and making the composition of the non-aqueous mobile phase suitable to support the positive atmospheric pressure chemical ionization of the analytes. An excellent selectivity resulted from the combination of some factors: the MRM acquisition, the adoption of an identification point system, an extraction optimized to remove most of the lipids and a tandem-C18 column-system necessary to separate isobaric interferences from analytes. The method was validated according to the Food and Drug Administration (FDA) guidelines and its accuracy was assessed by analysing 9 samples from the Vitamin K External Quality Assessment Scheme (KEQAS). Its feasibility in evaluating vitamin K status in human serum was

  14. Carpet Aids Learning in High Performance Schools

    Science.gov (United States)

    Hurd, Frank

    2009-01-01

    The Healthy and High Performance Schools Act of 2002 has set specific federal guidelines for school design, and developed a federal/state partnership program to assist local districts in their school planning. According to the Collaborative for High Performance Schools (CHPS), high-performance schools are, among other things, healthy, comfortable,…

  15. Electron-cyclotron plasma startup in the GDT experiment

    CERN Document Server

    Yakovlev, D V; Gospodchikov, E D; Solomakhin, A L; Savkin, V Ya; Bagryansky, P A

    2016-01-01

    The paper reports on a new plasma startup scenario in the Gas Dynamic Trap (GDT) magnetic mirror device. The primary 5 MW neutral beam injection (NBI) plasma heating system fires into a sufficiently dense plasma target ("seed plasma"), which is commonly supplied by an arc plasma generator. In the reported experiments, a different approach to seed plasma generation is explored. One of the channels of the electron cyclotron resonance (ECR) heating system is used to ionize the neutral gas and build up the density of plasma to a level suitable for NBI capture. After a short transition (about 1 ms) the discharge becomes essentially similar to a standard one initiated by the plasma gun. The paper presents the discharge scenario and experimental data on the seed plasma evolution during ECR heating, along with the dependencies on incident microwave power, magnetic configuration and pressure of a neutral gas. The characteristics of consequent high-power NBI discharge are studied and differences to the conventional sce...

  16. Electron cyclotron plasma startup in the GDT experiment

    Science.gov (United States)

    Yakovlev, D. V.; Shalashov, A. G.; Gospodchikov, E. D.; Solomakhin, A. L.; Savkin, V. Ya.; Bagryansky, P. A.

    2017-01-01

    We report on a new plasma startup scenario in the gas dynamic trap (GDT) magnetic mirror device. The primary 5 MW neutral beam injection (NBI) plasma heating system fires into a sufficiently dense plasma target (‘seed plasma’), which is commonly supplied by an arc plasma generator. In the reported experiments, a different approach to seed plasma generation is explored. One of the channels of the electron cyclotron resonance (ECR) heating system is used to ionize the neutral gas and build up the density of plasma to a level suitable for NBI capture. After a short transition of approximately 1 ms the discharge becomes essentially similar to a standard one initiated by the plasma gun. This paper presents the discharge scenario and experimental data on the seed plasma evolution during ECRH, along with the dependencies on incident microwave power, magnetic configuration and pressure of a neutral gas. The characteristics of the consequent high-power NBI discharge are studied and differences from the conventional scenario are discussed. A theoretical model describing the ECR breakdown and the seed plasma accumulation in a large-scale mirror trap is developed on the basis of the GDT experiment.

  17. ANALYSIS OF AMINO ACIDS BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

    Directory of Open Access Journals (Sweden)

    Qurat E Noor Baig

    2016-06-01

    Full Text Available Amino acids are the building blocks of proteins and are considered as the key precursors for the formation of hormones and low molecular weight nitrogenous substances with biological importance. Since the analysis of amino acids has been carried out for both qualitative and quantitative purposes with an aim to study their levels in the plasma concentration, the quantitative determination, in particular, also helps in the diagnosis of different diseases associated with their deficiency. This review article deals with the determination of amino acids by chromatographic methods which include ion-exchange chromatography (IEC, high performance liquid chromatography (HPLC, reverse phase-high performance liquid chromatography (RP-HPLC and ultra-performance liquid chromatography (UPLC. The review will also give an idea for the preparation of samples, derivatization methods for the analysis of amino acids (direct and indirect methods and separation of amino acids by high performance liquid chromatographic technique.

  18. High Performance Object-Oriented Scientific Programming in Fortran 90

    Science.gov (United States)

    Norton, Charles D.; Decyk, Viktor K.; Szymanski, Boleslaw K.

    1997-01-01

    We illustrate how Fortran 90 supports object-oriented concepts by example of plasma particle computations on the IBM SP. Our experience shows that Fortran 90 and object-oriented methodology give high performance while providing a bridge from Fortran 77 legacy codes to modern programming principles. All of our object-oriented Fortran 90 codes execute more quickly thatn the equeivalent C++ versions, yet the abstraction modelling capabilities used for scentific programming are comparably powereful.

  19. High performance computing and communications program

    Science.gov (United States)

    Holcomb, Lee

    1992-01-01

    A review of the High Performance Computing and Communications (HPCC) program is provided in vugraph format. The goals and objectives of this federal program are as follows: extend U.S. leadership in high performance computing and computer communications; disseminate the technologies to speed innovation and to serve national goals; and spur gains in industrial competitiveness by making high performance computing integral to design and production.

  20. High Performance Spaceflight Computing (HPSC) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In 2012, the NASA Game Changing Development Program (GCDP), residing in the NASA Space Technology Mission Directorate (STMD), commissioned a High Performance...

  1. High performance carbon nanocomposites for ultracapacitors

    Science.gov (United States)

    Lu, Wen

    2012-10-02

    The present invention relates to composite electrodes for electrochemical devices, particularly to carbon nanotube composite electrodes for high performance electrochemical devices, such as ultracapacitors.

  2. Confinement Studies in High Temperature Spheromak Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Hill, D N; Mclean, H S; Wood, R D; Casper, T A; Cohen, B I; Hooper, E B; LoDestro, L L; Pearlstein, L D; Romero-Talamas, C

    2006-10-23

    Recent results from the SSPX spheromak experiment demonstrate the potential for obtaining good energy confinement (Te > 350eV and radial electron thermal diffusivity comparable to tokamak L-mode values) in a completely self-organized toroidal plasma. A strong decrease in thermal conductivity with temperature is observed and at the highest temperatures, transport is well below that expected from the Rechester-Rosenbluth model. Addition of a new capacitor bank has produced 60% higher magnetic fields and almost tripled the pulse length to 11ms. For plasmas with T{sub e} > 300eV, it becomes feasible to use modest (1.8MW) neutral beam injection (NBI) heating to significantly change the power balance in the core plasma, making it an effective tool for improving transport analysis. We are now developing detailed designs for adding NBI to SSPX and have developed a new module for the CORSICA transport code to compute the correct fast-ion orbits in SSPX so that we can simulate the effect of adding NBI; initial results predict that such heating can raise the electron temperature and total plasma pressure in the core by a factor of two.

  3. An Associate Degree in High Performance Manufacturing.

    Science.gov (United States)

    Packer, Arnold

    In order for more individuals to enter higher paying jobs, employers must create a sufficient number of high-performance positions (the demand side), and workers must acquire the skills needed to perform in these restructured workplaces (the supply side). Creating an associate degree in High Performance Manufacturing (HPM) will help address four…

  4. Efficacy of Valbenazine (NBI-98854) in Treating Subjects with Tardive Dyskinesia and Schizophrenia or Schizoaffective Disorder.

    Science.gov (United States)

    Kane, John M; Correll, Christoph U; Liang, Grace S; Burke, Joshua; O'Brien, Christopher F

    2017-08-01

    Valbenazine (VBZ, NBI-98854) is a novel vesicular monoamine transporter 2 (VMAT2) inhibitor approved for the treatment of tardive dyskinesia (TD). The KINECT 3 study (NCT02274558) evaluated the effects of VBZ on TD in subjects with schizophrenia/schizoaffective disorder (SCHZ) or mood disorder (mood disorder presented separately) who received up to 48 weeks of treatment. KINECT 3 included: 6-week, double-blind, placebo (PBO)-controlled (DBPC) period (205 completers); 42-week VBZ extension (VE) period (124 completers): 4-week washout period (121 completers). Subjects entering the DBPC were randomized 1:1:1 to once-daily VBZ 80 mg, VBZ 40 mg, or PBO; stable concomitant antipsychotic medication regimens were allowed. Subjects completing the DBPC and entering the VE period were re-randomized (blinded) 1:1 from PBO to VBZ (80 or 40 mg) or continued VBZ treatment at the same dose. Efficacy assessments included: mean changes from baseline in Abnormal Involuntary Movement Scale (AIMS) total score (items 1-7); mean Clinical Global Impression of Change (CGI-TD) scores; AIMS responders (subjects with ≥50% score reduction from baseline): and CGI-TD responders (subjects with score ≤2 ["much improved" or "very much improved"]). Treatment effect sizes (Cohen's d) and numbers needed to treat (NNTs) were analyzed for DBPC outcomes. Efficacy analyses were conducted in 148 subjects (DBPC) and 125 subjects (VE) with SCHZ. At Week 6 (end of DBPC), AIMS mean score improvements were greater in the VBZ groups (in a dose-related pattern) than in the PBO group (80 mg, -2.9, d = 0.88; 40 mg, -1.6, d = 0.52; PBO, +0.3). AIMS score changes at Week 48 (end of VE) showed continued TD improvement during long-term VBZ treatment (80 mg, -4.2; 40 mg, -2.5). By Week 52 (end of washout), AIMS scores were returning toward baseline levels, indicating re-emergence of TD. CGI-TD mean scores were as follows: Week 6 (80 mg, 3.0, d = 0.11; 40 mg, 2.9, d = 0.23; PBO, 3.2), Week 48 (80 mg, 2.2; 40 mg, 2

  5. Strategy Guideline: High Performance Residential Lighting

    Energy Technology Data Exchange (ETDEWEB)

    Holton, J.

    2012-02-01

    The Strategy Guideline: High Performance Residential Lighting has been developed to provide a tool for the understanding and application of high performance lighting in the home. The high performance lighting strategies featured in this guide are drawn from recent advances in commercial lighting for application to typical spaces found in residential buildings. This guide offers strategies to greatly reduce lighting energy use through the application of high quality fluorescent and light emitting diode (LED) technologies. It is important to note that these strategies not only save energy in the home but also serve to satisfy the homeowner's expectations for high quality lighting.

  6. High Performance Grinding and Advanced Cutting Tools

    CERN Document Server

    Jackson, Mark J

    2013-01-01

    High Performance Grinding and Advanced Cutting Tools discusses the fundamentals and advances in high performance grinding processes, and provides a complete overview of newly-developing areas in the field. Topics covered are grinding tool formulation and structure, grinding wheel design and conditioning and applications using high performance grinding wheels. Also included are heat treatment strategies for grinding tools, using grinding tools for high speed applications, laser-based and diamond dressing techniques, high-efficiency deep grinding, VIPER grinding, and new grinding wheels.

  7. Radiation Hard High Performance Optoelectronic Devices Project

    Data.gov (United States)

    National Aeronautics and Space Administration — High-performance, radiation-hard, widely-tunable integrated laser/modulator chip and large-area avalanche photodetectors (APDs) are key components of optical...

  8. High Performance Methane Thrust Chamber (HPMTC) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC proposes to develop a High-Performance Methane Thrust Chamber (HPMRE) to meet the demands of advanced chemical propulsion systems for deep-space mission...

  9. High-performance computing using FPGAs

    CERN Document Server

    Benkrid, Khaled

    2013-01-01

    This book is concerned with the emerging field of High Performance Reconfigurable Computing (HPRC), which aims to harness the high performance and relative low power of reconfigurable hardware–in the form Field Programmable Gate Arrays (FPGAs)–in High Performance Computing (HPC) applications. It presents the latest developments in this field from applications, architecture, and tools and methodologies points of view. We hope that this work will form a reference for existing researchers in the field, and entice new researchers and developers to join the HPRC community.  The book includes:  Thirteen application chapters which present the most important application areas tackled by high performance reconfigurable computers, namely: financial computing, bioinformatics and computational biology, data search and processing, stencil computation e.g. computational fluid dynamics and seismic modeling, cryptanalysis, astronomical N-body simulation, and circuit simulation.     Seven architecture chapters which...

  10. Analog circuit design designing high performance amplifiers

    CERN Document Server

    Feucht, Dennis

    2010-01-01

    The third volume Designing High Performance Amplifiers applies the concepts from the first two volumes. It is an advanced treatment of amplifier design/analysis emphasizing both wideband and precision amplification.

  11. Prompt loss of beam ions in KSTAR plasmas

    Directory of Open Access Journals (Sweden)

    Jun Young Kim

    2016-10-01

    Full Text Available For a toroidal plasma facility to realize fusion energy, researching the transport of fast ions is important not only due to its close relation to the heating and current drive efficiencies but also to determine the heat load on the plasma-facing components. We present a theoretical analysis and orbit simulation for the origin of lost fast-ions during neutral beam injection (NBI heating in Korea Superconducting Tokamak Advanced Research (KSTAR device. We adopted a two-dimensional phase diagram of the toroidal momentum and magnetic moment and describe detectable momentums at the fast-ion loss detector (FILD position as a quadratic line. This simple method was used to model birth ions deposited by NBI and drawn as points in the momentum phase space. A Lorentz orbit code was used to calculate the fast-ion orbits and present the prompt loss characteristics of the KSTAR NBI. The scrape-off layer deposition of fast ions produces a significant prompt loss, and the model and experimental results closely agreed on the pitch-angle range of the NBI prompt loss. Our approach can provide wall load information from the fast ion loss.

  12. High performance computing in Windows Azure cloud

    OpenAIRE

    Ambruš, Dejan

    2013-01-01

    High performance, security, availability, scalability, flexibility and lower costs of maintenance have essentially contributed to the growing popularity of cloud computing in all spheres of life, especially in business. In fact cloud computing offers even more than this. With usage of virtual computing clusters a runtime environment for high performance computing can be efficiently implemented also in a cloud. There are many advantages but also some disadvantages of cloud computing, some ...

  13. High performance protection circuit for power electronics applications

    Science.gov (United States)

    Tudoran, Cristian D.; Dǎdârlat, Dorin N.; Toşa, Nicoleta; Mişan, Ioan

    2015-12-01

    In this paper we present a high performance protection circuit designed for the power electronics applications where the load currents can increase rapidly and exceed the maximum allowed values, like in the case of high frequency induction heating inverters or high frequency plasma generators. The protection circuit is based on a microcontroller and can be adapted for use on single-phase or three-phase power systems. Its versatility comes from the fact that the circuit can communicate with the protected system, having the role of a "sensor" or it can interrupt the power supply for protection, in this case functioning as an external, independent protection circuit.

  14. High performance protection circuit for power electronics applications

    Energy Technology Data Exchange (ETDEWEB)

    Tudoran, Cristian D., E-mail: cristian.tudoran@itim-cj.ro; Dădârlat, Dorin N.; Toşa, Nicoleta; Mişan, Ioan [National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, PO 5 Box 700, 400293 Cluj-Napoca (Romania)

    2015-12-23

    In this paper we present a high performance protection circuit designed for the power electronics applications where the load currents can increase rapidly and exceed the maximum allowed values, like in the case of high frequency induction heating inverters or high frequency plasma generators. The protection circuit is based on a microcontroller and can be adapted for use on single-phase or three-phase power systems. Its versatility comes from the fact that the circuit can communicate with the protected system, having the role of a “sensor” or it can interrupt the power supply for protection, in this case functioning as an external, independent protection circuit.

  15. Alternative High-Performance Ceramic Waste Forms

    Energy Technology Data Exchange (ETDEWEB)

    Sundaram, S. K. [Alfred Univ., NY (United States)

    2017-02-01

    This final report (M5NU-12-NY-AU # 0202-0410) summarizes the results of the project titled “Alternative High-Performance Ceramic Waste Forms,” funded in FY12 by the Nuclear Energy University Program (NEUP Project # 12-3809) being led by Alfred University in collaboration with Savannah River National Laboratory (SRNL). The overall focus of the project is to advance fundamental understanding of crystalline ceramic waste forms and to demonstrate their viability as alternative waste forms to borosilicate glasses. We processed single- and multiphase hollandite waste forms based on simulated waste streams compositions provided by SRNL based on the advanced fuel cycle initiative (AFCI) aqueous separation process developed in the Fuel Cycle Research and Development (FCR&D). For multiphase simulated waste forms, oxide and carbonate precursors were mixed together via ball milling with deionized water using zirconia media in a polyethylene jar for 2 h. The slurry was dried overnight and then separated from the media. The blended powders were then subjected to melting or spark plasma sintering (SPS) processes. Microstructural evolution and phase assemblages of these samples were studied using x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersion analysis of x-rays (EDAX), wavelength dispersive spectrometry (WDS), transmission electron spectroscopy (TEM), selective area x-ray diffraction (SAXD), and electron backscatter diffraction (EBSD). These results showed that the processing methods have significant effect on the microstructure and thus the performance of these waste forms. The Ce substitution into zirconolite and pyrochlore materials was investigated using a combination of experimental (in situ XRD and x-ray absorption near edge structure (XANES)) and modeling techniques to study these single phases independently. In zirconolite materials, a transition from the 2M to the 4M polymorph was observed with increasing Ce content. The resulting

  16. Strategy Guideline. Partnering for High Performance Homes

    Energy Technology Data Exchange (ETDEWEB)

    Prahl, Duncan [IBACOS, Inc., Pittsburgh, PA (United States)

    2013-01-01

    High performance houses require a high degree of coordination and have significant interdependencies between various systems in order to perform properly, meet customer expectations, and minimize risks for the builder. Responsibility for the key performance attributes is shared across the project team and can be well coordinated through advanced partnering strategies. For high performance homes, traditional partnerships need to be matured to the next level and be expanded to all members of the project team including trades, suppliers, manufacturers, HERS raters, designers, architects, and building officials as appropriate. This guide is intended for use by all parties associated in the design and construction of high performance homes. It serves as a starting point and features initial tools and resources for teams to collaborate to continually improve the energy efficiency and durability of new houses.

  17. Optimization and validation of high performance liquid ...

    African Journals Online (AJOL)

    Relative standard deviation (RSD) of intra- day and inter-day precision was < 14.27 and 7.61 %, respectively. Relative error of accuracy was between 4.85 and 14.37 %. Maximum plasma concentration (Cmax), time to maximum plasma concentration (Tmax) and half-life (t½) after metoprolol oral administration in rabbits ...

  18. Toward High Performance in Industrial Refrigeration Systems

    DEFF Research Database (Denmark)

    Thybo, C.; Izadi-Zamanabadi, Roozbeh; Niemann, H.

    2002-01-01

    Achieving high performance in complex industrial systems requires information manipulation at different system levels. The paper shows how different models of same subsystems, but using different quality of information/data, are used for fault diagnosis as well as robust control design in industr......Achieving high performance in complex industrial systems requires information manipulation at different system levels. The paper shows how different models of same subsystems, but using different quality of information/data, are used for fault diagnosis as well as robust control design...... in industrial refrigeration systems....

  19. Towards High Performance in Industrial Refrigeration Systems

    DEFF Research Database (Denmark)

    Thybo, C.; Izadi-Zamanabadi, Roozbeh; Niemann, H.

    2002-01-01

    Achieving high performance in complex industrial systems requires information manipulation at different system levels. The paper shows how different models of same subsystems, but using different quality of information/data, are used for fault diagnosis as well as robust control design in industr......Achieving high performance in complex industrial systems requires information manipulation at different system levels. The paper shows how different models of same subsystems, but using different quality of information/data, are used for fault diagnosis as well as robust control design...... in industrial refrigeration systems....

  20. High performance parallel I/O

    CERN Document Server

    Prabhat

    2014-01-01

    Gain Critical Insight into the Parallel I/O EcosystemParallel I/O is an integral component of modern high performance computing (HPC), especially in storing and processing very large datasets to facilitate scientific discovery. Revealing the state of the art in this field, High Performance Parallel I/O draws on insights from leading practitioners, researchers, software architects, developers, and scientists who shed light on the parallel I/O ecosystem.The first part of the book explains how large-scale HPC facilities scope, configure, and operate systems, with an emphasis on choices of I/O har

  1. High performance computing at Sandia National Labs

    Energy Technology Data Exchange (ETDEWEB)

    Cahoon, R.M.; Noe, J.P.; Vandevender, W.H.

    1995-10-01

    Sandia`s High Performance Computing Environment requires a hierarchy of resources ranging from desktop, to department, to centralized, and finally to very high-end corporate resources capable of teraflop performance linked via high-capacity Asynchronous Transfer Mode (ATM) networks. The mission of the Scientific Computing Systems Department is to provide the support infrastructure for an integrated corporate scientific computing environment that will meet Sandia`s needs in high-performance and midrange computing, network storage, operational support tools, and systems management. This paper describes current efforts at SNL/NM to expand and modernize centralized computing resources in support of this mission.

  2. Estudo pré-analítico e de validação para determinação de malondialdeído em plasma humano por cromatografia líquida de alta eficiência, após derivatização com 2,4-dinitrofenilhidrazina Preanalytical and validation studies for the determination of malondialdehyde in human plasma through high performance liquid chromatography after derivatization with 2,4-dinitrophenylhydrazine

    Directory of Open Access Journals (Sweden)

    Marina Venzon Antunes

    2008-06-01

    Full Text Available O malondialdeído (MDA é um importante biomarcador utilizado na avaliação do estresse oxidativo. O objetivo deste estudo foi desenvolver uma metodologia para a quantificação plasmática de MDA, através de cromatografia líquida de alta eficiência com detecção por arranjo de diodos (CLAE-DAD, após processo de derivatização com 2,4-dinitrofenilhidrazina (DNPH, avaliando as principais variáveis pré-analíticas. A curva de calibração em plasma (0 a 40 µM apresentou elevada linearidade (r²=0,998. Os principais parâmetros de validação foram: recuperação absoluta: 78%; limite de detecção: 0,11 µM e limite de quantificação: 0,38 µM. Os valores de MDA determinados em indivíduos adultos saudáveis (n=38 foram 3,31 ± 0,38 µM (média ± DP. Estudos de estabilidade do padrão de MDA, reagente derivatizante e MDA plasmáticos, indicaram que a solução padrão pode ser armazenada a -20 e 4 ºC.Malondialdehyde (MDA is an important biomarker for the evaluation of oxidative stress status. The aim of this study was to develop a method for plasma MDA quantification by high performance liquid chromatography with diode-array detection (HPLC-DAD, following derivatization with 2,4-dinitrophenylhydrazine (DNPH, evaluating the main preanalytical variables. The calibration curve in plasma (0 to 40 µM presented high linearity (r² = 0.998. Main validation parameters were: recovery: 78%; LOD: 0.11 µM and LOQ: 0.38 µM. The MDA values obtained in healthy volunteers (n=38 were 3.31 ± 0.38 µM (mean ± SD. Stability studies of MDA standard solution and derivatizing reagent and plasma MDA indicated that the standard solution can be stored at -20 and 4 ºC, remaining stable for at least 30 days.

  3. Plasma Response to Lithium-Coated Plasma-Facing Components in the National Spherical Torus Experiment

    Energy Technology Data Exchange (ETDEWEB)

    M.G. Bell, H.W. Kugel, R. Kaita, L.E. Zakharov, H. Schneider, B.P. LeBlanc, D. Mansfield, R.E. Bell, R. Maingi, S. Ding, S.M. Kaye, S.F. Paul, S.P. Gerhardt, J.M. Canik, J.C. Hosea, G. Taylor and the NSTX Research Team

    2009-08-20

    Experiments in the National Spherical Torus Experiment (NSTX) have shown beneficial effects on the performance of divertor plasmas as a result of applying lithium coatings on the graphite and carbonfiber- composite plasma-facing components. These coatings have mostly been applied by a pair of lithium evaporators mounted at the top of the vacuum vessel which inject collimated streams of lithium vapor towards the lower divertor. In NBI-heated, deuterium H-mode plasmas run immediately after the application of lithium, performance modifications included decreases in the plasma density, particularly in the edge, and inductive flux consumption, and increases in the electron and ion temperatures and the energy confinement time. Reductions in the number and amplitude of ELMs were observed, including complete ELM suppression for periods up to 1.2 s, apparently as a result of altering the stability of the edge. However, in the plasmas where ELMs were suppressed, there was a significant secular increase in the effective ion charge Zeff and the radiated power as a result of increases in the carbon and medium-Z metallic impurities, although not of lithium itself which remained at a very low level in the plasma core, <0.1%. The impurity buildup could be inhibited by repetitively triggering ELMs with the application of brief pulses of an n = 3 radial field perturbation. The reduction in the edge density by lithium also inhibited parasitic losses through the scrape-off layer of ICRF power coupled to the plasma, enabling the waves to heat electrons in the core of H-mode plasmas produced by NBI. Lithium has also been introduced by injecting a stream of chemically stabilized, fine lithium powder directly into the scrape-off layer of NBI-heated plasmas. The lithium was ionized in the SOL and appeared to flow along the magnetic field to the divertor plates. This method of coating produced similar effects to the evaporated lithium but at lower amounts.

  4. High Performance Networks for High Impact Science

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Mary A.; Bair, Raymond A.

    2003-02-13

    This workshop was the first major activity in developing a strategic plan for high-performance networking in the Office of Science. Held August 13 through 15, 2002, it brought together a selection of end users, especially representing the emerging, high-visibility initiatives, and network visionaries to identify opportunities and begin defining the path forward.

  5. An Introduction to High Performance Fortran

    Directory of Open Access Journals (Sweden)

    John Merlin

    1995-01-01

    Full Text Available High Performance Fortran (HPF is an informal standard for extensions to Fortran 90 to assist its implementation on parallel architectures, particularly for data-parallel computation. Among other things, it includes directives for specifying data distribution across multiple memories, and concurrent execution features. This article provides a tutorial introduction to the main features of HPF.

  6. Debugging a high performance computing program

    Science.gov (United States)

    Gooding, Thomas M.

    2013-08-20

    Methods, apparatus, and computer program products are disclosed for debugging a high performance computing program by gathering lists of addresses of calling instructions for a plurality of threads of execution of the program, assigning the threads to groups in dependence upon the addresses, and displaying the groups to identify defective threads.

  7. High Performance Work Systems for Online Education

    Science.gov (United States)

    Contacos-Sawyer, Jonna; Revels, Mark; Ciampa, Mark

    2010-01-01

    The purpose of this paper is to identify the key elements of a High Performance Work System (HPWS) and explore the possibility of implementation in an online institution of higher learning. With the projected rapid growth of the demand for online education and its importance in post-secondary education, providing high quality curriculum, excellent…

  8. Project materials [Commercial High Performance Buildings Project

    Energy Technology Data Exchange (ETDEWEB)

    None

    2001-01-01

    The Consortium for High Performance Buildings (ChiPB) is an outgrowth of DOE'S Commercial Whole Buildings Roadmapping initiatives. It is a team-driven public/private partnership that seeks to enable and demonstrate the benefit of buildings that are designed, built and operated to be energy efficient, environmentally sustainable, superior quality, and cost effective.

  9. Comparing Dutch and British high performing managers

    NARCIS (Netherlands)

    Waal, A.A. de; Heijden, B.I.J.M. van der; Selvarajah, C.; Meyer, D.

    2016-01-01

    National cultures have a strong influence on the performance of organizations and should be taken into account when studying the traits of high performing managers. At the same time, many studies that focus upon the attributes of successful managers show that there are attributes that are similar

  10. High performance computing on vector systems

    CERN Document Server

    Roller, Sabine

    2008-01-01

    Presents the developments in high-performance computing and simulation on modern supercomputer architectures. This book covers trends in hardware and software development in general and specifically the vector-based systems and heterogeneous architectures. It presents innovative fields like coupled multi-physics or multi-scale simulations.

  11. Performance, Performance System, and High Performance System

    Science.gov (United States)

    Jang, Hwan Young

    2009-01-01

    This article proposes needed transitions in the field of human performance technology. The following three transitions are discussed: transitioning from training to performance, transitioning from performance to performance system, and transitioning from learning organization to high performance system. A proposed framework that comprises…

  12. Gradient High Performance Liquid Chromatography Method ...

    African Journals Online (AJOL)

    Purpose: To develop a gradient high performance liquid chromatography (HPLC) method for the simultaneous determination of phenylephrine (PHE) and ibuprofen (IBU) in solid dosage form. Methods: HPLC determination was carried out on an Agilent XDB C-18 column (4.6 x 150mm, 5 μ particle size) with a gradient ...

  13. Teacher Accountability at High Performing Charter Schools

    Science.gov (United States)

    Aguirre, Moises G.

    2016-01-01

    This study will examine the teacher accountability and evaluation policies and practices at three high performing charter schools located in San Diego County, California. Charter schools are exempted from many laws, rules, and regulations that apply to traditional school systems. By examining the teacher accountability systems at high performing…

  14. Technology Leadership in Malaysia's High Performance School

    Science.gov (United States)

    Yieng, Wong Ai; Daud, Khadijah Binti

    2017-01-01

    Headmaster as leader of the school also plays a role as a technology leader. This applies to the high performance schools (HPS) headmaster as well. The HPS excel in all aspects of education. In this study, researcher is interested in examining the role of the headmaster as a technology leader through interviews with three headmasters of high…

  15. High Performance Computing and Communications Panel Report.

    Science.gov (United States)

    President's Council of Advisors on Science and Technology, Washington, DC.

    This report offers advice on the strengths and weaknesses of the High Performance Computing and Communications (HPCC) initiative, one of five presidential initiatives launched in 1992 and coordinated by the Federal Coordinating Council for Science, Engineering, and Technology. The HPCC program has the following objectives: (1) to extend U.S.…

  16. High Performance Liquid Chromatographic Determination of ...

    African Journals Online (AJOL)

    Purpose: To develop a simple, precise and rapid high-performance liquid chromatographic technique coupled with photodiode array detection (DAD) method for the simultaneous determination of rutin, quercetin, luteolin, genistein, galangin and curcumin in propolis. Methods: Ultrasound-assisted extraction was applied to ...

  17. High-performance computing reveals missing genes

    OpenAIRE

    Whyte, Barry James

    2010-01-01

    Scientists at the Virginia Bioinformatics Institute and the Department of Computer Science at Virginia Tech have used high-performance computing to locate small genes that have been missed by scientists in their quest to define the microbial DNA sequences of life.

  18. Recent developments of long pulse RF ion sources for NBI systems

    Energy Technology Data Exchange (ETDEWEB)

    Kraus, W. E-mail: wrk@ipp.mpg.de; Franzen, P.; Heinemann, B.; Speth, E.; Vollmer, O

    2001-10-01

    For the new radial injector of the Wendelstein 7-AS stellerator, two medium size 40 kW RF sources ('W7-AS RF source') have been built and tested. A positive hydrogen ion beam of 28 A at 50 kV with a proton fraction of 60% has been extracted. For future injection systems, in particular those based on negative ions, large area beam extraction and long pulse capability up to cw operation are envisaged. At IPP two different design concepts of RF sources are being investigated in order to meet these requirements: in the first one, the plasma is generated in one or two small circular RF sources ('drivers'), which are mounted onto the back plate of a 30 l expansion volume ('bucket') with magnetic multi-cusp confinement of the plasma ('Type 6-1' and 'Type 6-2' respectively). In the second concept the plasma is generated inside the bucket by an internal RF coil, which is insulated by a quartz tube ('Type 5'). In both cases the applicability for negative as well as for positive ion production is being tested. The next application will be in the positive ion based injectors in the third injector of JET and in the W7X stellerator.

  19. Improvement of a plasma uniformity of the 2nd ion source of KSTAR neutral beam injector.

    Science.gov (United States)

    Jeong, S H; Kim, T S; Lee, K W; Chang, D H; In, S R; Bae, Y S

    2014-02-01

    The 2nd ion source of KSTAR (Korea Superconducting Tokamak Advanced Research) NBI (Neutral Beam Injector) had been developed and operated since last year. A calorimetric analysis revealed that the heat load of the back plate of the ion source is relatively higher than that of the 1st ion source of KSTAR NBI. The spatial plasma uniformity of the ion source is not good. Therefore, we intended to identify factors affecting the uniformity of a plasma density and improve it. We estimated the effects of a direction of filament current and a magnetic field configuration of the plasma generator on the plasma uniformity. We also verified that the operation conditions of an ion source could change a uniformity of the plasma density of an ion source.

  20. Validated High Performance Liquid Chromatography Method for ...

    African Journals Online (AJOL)

    The method was selective to determine cefadroxil in plasma because there was no peak interference of plasma with cefadroxil at its retention time (7.792 min). Linearity was in the range of 0.5 - 30 μg/ml with slope and intercept of 41694.53 and 22614.87, respectively (R2 = 0.9953). Limit of detection (LOD) and lower limit of ...

  1. Validated High Performance Liquid Chromatography Method for ...

    African Journals Online (AJOL)

    absorbed through gastrointestinal tract and protein binding is just 20 %. Plasma half-life is. 1.5 h. Most of the drug is excreted unchanged in urine. Side effects of .... and intercept of 41694.53 and 22614.87, respectively (R2 = 0.9953). Fig 2: Chromatogram of blank human plasma. 0.0. 2.5. 5.0. 7.5. 10.0 min. 0. 50. 100. 150.

  2. Architecting Web Sites for High Performance

    Directory of Open Access Journals (Sweden)

    Arun Iyengar

    2002-01-01

    Full Text Available Web site applications are some of the most challenging high-performance applications currently being developed and deployed. The challenges emerge from the specific combination of high variability in workload characteristics and of high performance demands regarding the service level, scalability, availability, and costs. In recent years, a large body of research has addressed the Web site application domain, and a host of innovative software and hardware solutions have been proposed and deployed. This paper is an overview of recent solutions concerning the architectures and the software infrastructures used in building Web site applications. The presentation emphasizes three of the main functions in a complex Web site: the processing of client requests, the control of service levels, and the interaction with remote network caches.

  3. High performance cloud auditing and applications

    CERN Document Server

    Choi, Baek-Young; Song, Sejun

    2014-01-01

    This book mainly focuses on cloud security and high performance computing for cloud auditing. The book discusses emerging challenges and techniques developed for high performance semantic cloud auditing, and presents the state of the art in cloud auditing, computing and security techniques with focus on technical aspects and feasibility of auditing issues in federated cloud computing environments.   In summer 2011, the United States Air Force Research Laboratory (AFRL) CyberBAT Cloud Security and Auditing Team initiated the exploration of the cloud security challenges and future cloud auditing research directions that are covered in this book. This work was supported by the United States government funds from the Air Force Office of Scientific Research (AFOSR), the AFOSR Summer Faculty Fellowship Program (SFFP), the Air Force Research Laboratory (AFRL) Visiting Faculty Research Program (VFRP), the National Science Foundation (NSF) and the National Institute of Health (NIH). All chapters were partially suppor...

  4. Failure analysis of high performance ballistic fibers

    OpenAIRE

    Spatola, Jennifer S

    2015-01-01

    High performance fibers have a high tensile strength and modulus, good wear resistance, and a low density, making them ideal for applications in ballistic impact resistance, such as body armor. However, the observed ballistic performance of these fibers is much lower than the predicted values. Since the predictions assume only tensile stress failure, it is safe to assume that the stress state is affecting fiber performance. The purpose of this research was to determine if there are failure mo...

  5. Performance tuning for high performance computing systems

    OpenAIRE

    Pahuja, Himanshu

    2017-01-01

    A Distributed System is composed by integration between loosely coupled software components and the underlying hardware resources that can be distributed over the standard internet framework. High Performance Computing used to involve utilization of supercomputers which could churn a lot of computing power to process massively complex computational tasks, but is now evolving across distributed systems, thereby having the ability to utilize geographically distributed computing resources. We...

  6. Nanoparticles for high performance concrete (HPC)

    OpenAIRE

    Torgal, Fernando Pacheco; Miraldo, Sérgio; Ding, Yining; J.A. Labrincha

    2013-01-01

    According to the 2011 ERMCO statistics, only 11% of the production of ready-mixed concrete relates to the high performance concrete (HPC) target. This percentage has remained unchanged since at least 2001 and appears a strange choice on the part of the construction industry, as HPC offers several advantages over normal-strength concrete, specifically those of high strength and durability. It allows for concrete structures requiring less steel reinforcement and offers a longer serviceable life...

  7. Robust High Performance Aquaporin based Biomimetic Membranes

    DEFF Research Database (Denmark)

    Helix Nielsen, Claus; Zhao, Yichun; Qiu, C.

    2013-01-01

    Aquaporins are water channel proteins with high water permeability and solute rejection, which makes them promising for preparing high-performance biomimetic membranes. Despite the growing interest in aquaporin-based biomimetic membranes (ABMs), it is challenging to produce robust and defect......% rejection for urea and a water permeability around 10 L/(m2h) with 2M NaCl as draw solution. Our results demonstrate the feasibility of using aquaporin proteins in biomimetic membranes for technological applications....

  8. High Performance Computing Operations Review Report

    Energy Technology Data Exchange (ETDEWEB)

    Cupps, Kimberly C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2013-12-19

    The High Performance Computing Operations Review (HPCOR) meeting—requested by the ASC and ASCR program headquarters at DOE—was held November 5 and 6, 2013, at the Marriott Hotel in San Francisco, CA. The purpose of the review was to discuss the processes and practices for HPC integration and its related software and facilities. Experiences and lessons learned from the most recent systems deployed were covered in order to benefit the deployment of new systems.

  9. High performance work practices, innovation and performance

    DEFF Research Database (Denmark)

    Jørgensen, Frances; Newton, Cameron; Johnston, Kim

    2013-01-01

    Research spanning nearly 20 years has provided considerable empirical evidence for relationships between High Performance Work Practices (HPWPs) and various measures of performance including increased productivity, improved customer service, and reduced turnover. What stands out from......, and Africa to examine these various questions relating to the HPWP-innovation-performance relationship. Each paper discusses a practice that has been identified in HPWP literature and potential variables that can facilitate or hinder the effects of these practices of innovation- and performance...

  10. vSphere high performance cookbook

    CERN Document Server

    Sarkar, Prasenjit

    2013-01-01

    vSphere High Performance Cookbook is written in a practical, helpful style with numerous recipes focusing on answering and providing solutions to common, and not-so common, performance issues and problems.The book is primarily written for technical professionals with system administration skills and some VMware experience who wish to learn about advanced optimization and the configuration features and functions for vSphere 5.1.

  11. High Performance Electronics on Flexible Silicon

    KAUST Repository

    Sevilla, Galo T.

    2016-09-01

    Over the last few years, flexible electronic systems have gained increased attention from researchers around the world because of their potential to create new applications such as flexible displays, flexible energy harvesters, artificial skin, and health monitoring systems that cannot be integrated with conventional wafer based complementary metal oxide semiconductor processes. Most of the current efforts to create flexible high performance devices are based on the use of organic semiconductors. However, inherent material\\'s limitations make them unsuitable for big data processing and high speed communications. The objective of my doctoral dissertation is to develop integration processes that allow the transformation of rigid high performance electronics into flexible ones while maintaining their performance and cost. In this work, two different techniques to transform inorganic complementary metal-oxide-semiconductor electronics into flexible ones have been developed using industry compatible processes. Furthermore, these techniques were used to realize flexible discrete devices and circuits which include metal-oxide-semiconductor field-effect-transistors, the first demonstration of flexible Fin-field-effect-transistors, and metal-oxide-semiconductors-based circuits. Finally, this thesis presents a new technique to package, integrate, and interconnect flexible high performance electronics using low cost additive manufacturing techniques such as 3D printing and inkjet printing. This thesis contains in depth studies on electrical, mechanical, and thermal properties of the fabricated devices.

  12. Supervising the highly performing general practice registrar.

    Science.gov (United States)

    Morgan, Simon

    2014-02-01

    There is extensive literature on the poorly performing learner. In contrast, there is very little written on supervising the highly performing registrar. Outstanding trainees with high-level knowledge and skills can be a challenge for supervisors to supervise and teach. Narrative review and discussion. As with all learners, a learning-needs analysis is fundamental to successful supervision. The key to effective teaching of the highly performing registrar is to contextualise clinical knowledge and skills with the wisdom of accumulated experience. Moreover, supervisors must provide a stimulating learning environment, with regular opportunities for intellectual challenge. The provision of specific, constructive feedback is essential. There are potential opportunities to extend the highly performing registrar in all domains of general practice, namely communication skills and patient-centred care, applied knowledge and skills, population health, professionalism, and organisation and legal issues. Specific teaching strategies include role-play, video-consultation review, random case analysis, posing hypothetical clinical scenarios, role modelling and teaching other learners. © 2014 John Wiley & Sons Ltd.

  13. High Performance with Prescriptive Optimization and Debugging

    DEFF Research Database (Denmark)

    Jensen, Nicklas Bo

    Parallel programming is the dominant approach to achieve high performance in computing today. Correctly writing efficient and fast parallel programs is a big challenge mostly carried out by experts. We investigate optimization and debugging of parallel programs. We argue that automatic paralleliz......Parallel programming is the dominant approach to achieve high performance in computing today. Correctly writing efficient and fast parallel programs is a big challenge mostly carried out by experts. We investigate optimization and debugging of parallel programs. We argue that automatic...... analysis and vectorizer in GCC. Automatic optimizations often fail for theoretical and practical reasons. When they fail we argue that a hybrid approach can be effective. Using compiler feedback, we propose to use the programmer’s intuition and insight to achieve high performance. Compiler feedback...... the prescriptive debugging model, which is a user-guided model that allows the programmer to use his intuition to diagnose bugs in parallel programs. The model is scalable, yet capable enough, to be general-purpose. In our evaluation we demonstrate low run time overhead and logarithmic scalability. This enable...

  14. Computational Biology and High Performance Computing 2000

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Horst D.; Zorn, Manfred D.; Spengler, Sylvia J.; Shoichet, Brian K.; Stewart, Craig; Dubchak, Inna L.; Arkin, Adam P.

    2000-10-19

    The pace of extraordinary advances in molecular biology has accelerated in the past decade due in large part to discoveries coming from genome projects on human and model organisms. The advances in the genome project so far, happening well ahead of schedule and under budget, have exceeded any dreams by its protagonists, let alone formal expectations. Biologists expect the next phase of the genome project to be even more startling in terms of dramatic breakthroughs in our understanding of human biology, the biology of health and of disease. Only today can biologists begin to envision the necessary experimental, computational and theoretical steps necessary to exploit genome sequence information for its medical impact, its contribution to biotechnology and economic competitiveness, and its ultimate contribution to environmental quality. High performance computing has become one of the critical enabling technologies, which will help to translate this vision of future advances in biology into reality. Biologists are increasingly becoming aware of the potential of high performance computing. The goal of this tutorial is to introduce the exciting new developments in computational biology and genomics to the high performance computing community.

  15. Beam acceleration test in negative-ion based NBI system for JT-60U

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, K.; Akino, N.; Araki, M.; Ebisawa, N.; Fujiwara, Y.; Hanada, M.; Honda, A.; Inoue, T.; Itoh, T.; Kawai, M.; Kazawa, M.; Koizumi, J.; Kuriyama, M.; Miyamoto, K.; Miyamoto, N.; Mogaki, K.; Nagase, A.; Ohara, Y.; Ohga, T.; Okumura, Y.; Oohara, H.; Ohshima, K.; Satoh, F.; Takahashi, S.; Takenouchi, T.; Usami, H.; Usui, K.; Yamamoto, M.; Yamazaki, T. [Japan Atomic Energy Research Institute, Naka-machi, Naka-gun, Ibaraki-ken, 311-01 (Japan)

    1996-07-01

    Beam extraction and acceleration test in the Negative Ion Based Neutral Beam Injector for JT-60U has been started using one ion source that is designed to produce a 500 keV, 22 A D{sup {minus}} ion beam. Deuterium negative ions are produced in a cesium-seeded semi-cylindrical plasma generator and accelerated by a multi-aperture three-stage electrostatic accelerator. In the preliminary experiment of beam acceleration, the D{sup {minus}} ion beam of 13.5 A was successfully accelerated to 400 keV for a pulse duration of 0.12 s. The negative ion beam power was 5.4 MW. The operating gas pressure in the plasma generator was as low as 0.22 Pa. The highest energy beam of 460 keV, 2.4 A, 0.44 s was also obtained. The ratio of extracted electron current to extracted negative ion current is estimated Ie/I{sub D{sup {minus}}}{lt}1. It was confirmed that the electron leak from the extractor to the accelerator is suppressed efficiently by the effects of biassing, electron trapping gap and magnetic field. {copyright} {ital 1996 American Institute of Physics.}

  16. ANALYSIS OF COMBINED FWCD AND NBI IN THE DIII-D TOKAMAK

    Energy Technology Data Exchange (ETDEWEB)

    MANTSINEN, M.J.; PETTY, C.C.; ERIKSSON, L.-G.; MAU, T.K.; PINSKER, R.I.; PORKOLAB, M.

    2001-08-01

    In recent experiments with combined fast wave current drive (FWCD) and deuterium neutral beam injection on the DIII-D tokamak [Luxon and Davis, Fusion Technol. 8, 441 (1985)], an enhanced fusion reactivity and fast ion energy content have been observed in the presence of FWCD, with a concomitant low FWCD efficiency [Petty et al., Radio Frequency Power in Plasmas (AIP, New York, 1997), p. 225]. In this paper, we investigate whether high-harmonic ion cyclotron damping could be responsible for the low FWCD efficiency in these experiments, since a number of high-harmonic hydrogen and deuterium cyclotron resonance layers existed in the plasma. The main analysis tool is the ICRF code PION [Eriksson, Hellsten and Willen, Nucl. Fusion 33, 1037 (1993)], modified to allow multiple frequencies simultaneously as was done in the DIII-D experiments. According to the PION modeling, high harmonic damping of fast wave power can give rise to enhanced fusion reactivity and fast ion energy content, which is consistent with the experimental observations.

  17. Toward a theory of high performance.

    Science.gov (United States)

    Kirby, Julia

    2005-01-01

    What does it mean to be a high-performance company? The process of measuring relative performance across industries and eras, declaring top performers, and finding the common drivers of their success is such a difficult one that it might seem a fool's errand to attempt. In fact, no one did for the first thousand or so years of business history. The question didn't even occur to many scholars until Tom Peters and Bob Waterman released In Search of Excellence in 1982. Twenty-three years later, we've witnessed several more attempts--and, just maybe, we're getting closer to answers. In this reported piece, HBR senior editor Julia Kirby explores why it's so difficult to study high performance and how various research efforts--including those from John Kotter and Jim Heskett; Jim Collins and Jerry Porras; Bill Joyce, Nitin Nohria, and Bruce Roberson; and several others outlined in a summary chart-have attacked the problem. The challenge starts with deciding which companies to study closely. Are the stars the ones with the highest market caps, the ones with the greatest sales growth, or simply the ones that remain standing at the end of the game? (And when's the end of the game?) Each major study differs in how it defines success, which companies it therefore declares to be worthy of emulation, and the patterns of activity and attitude it finds in common among them. Yet, Kirby concludes, as each study's method incrementally solves problems others have faced, we are progressing toward a consensus theory of high performance.

  18. High performance HRM: NHS employee perspectives.

    Science.gov (United States)

    Hyde, Paula; Sparrow, Paul; Boaden, Ruth; Harris, Claire

    2013-01-01

    The purpose of this paper is to examine National Health Service (NHS) employee perspectives of how high performance human resource (HR) practices contribute to their performance. The paper draws on an extensive qualitative study of the NHS. A novel two-part method was used; the first part used focus group data from managers to identify high-performance HR practices specific to the NHS. Employees then conducted a card-sort exercise where they were asked how or whether the practices related to each other and how each practice affected their work. In total, 11 high performance HR practices relevant to the NHS were identified. Also identified were four reactions to a range of HR practices, which the authors developed into a typology according to anticipated beneficiaries (personal gain, organisation gain, both gain and no-one gains). Employees were able to form their own patterns (mental models) of performance contribution for a range of HR practices (60 interviewees produced 91 groupings). These groupings indicated three bundles particular to the NHS (professional development, employee contribution and NHS deal). These mental models indicate employee perceptions about how health services are organised and delivered in the NHS and illustrate the extant mental models of health care workers. As health services are rearranged and financial pressures begin to bite, these mental models will affect employee reactions to changes both positively and negatively. The novel method allows for identification of mental models that explain how NHS workers understand service delivery. It also delineates the complex and varied relationships between HR practices and individual performance.

  19. Optimization and validation of high performance liquid ...

    African Journals Online (AJOL)

    Conclusion: A simple, accurate and precise HPLC-UV method for metoprolol determination in rabbit plasma has been successfully developed .... immediately for 5 min in vortex mixer at speed of. 1200 rpm/min. After mixing, the mixture .... DECLARATIONS. Acknowledgement. The authors are thankful to Higher Education.

  20. Strategy Guideline. High Performance Residential Lighting

    Energy Technology Data Exchange (ETDEWEB)

    Holton, J. [IBACOS, Inc., Pittsburgh, PA (United States)

    2012-02-01

    This report has been developed to provide a tool for the understanding and application of high performance lighting in the home. The strategies featured in this guide are drawn from recent advances in commercial lighting for application to typical spaces found in residential buildings. This guide offers strategies to greatly reduce lighting energy use through the application of high quality fluorescent and light emitting diode (LED) technologies. It is important to note that these strategies not only save energy in the home but also serve to satisfy the homeowner’s expectations for high quality lighting.

  1. The monogroove high performance heat pipe

    Science.gov (United States)

    Alario, J.; Haslett, R.; Kosson, R.

    1981-06-01

    The development of the monogroove heat pipe, a fundamentally new high-performance device suitable for multi-kilowatt space radiator heat-rejection systems, is reported. The design separates heat transport and transfer functions, so that each can be separately optimized to yield heat transport capacities on the order of 25 kW/m. Test versions of the device have proven the concept of heat transport capacity control by pore dimensions and the permeability of the circumferential wall wick structure, which together render it insensitive to tilt. All cases tested were for localized, top-side heat input and cooling and produced results close to theoretical predictions.

  2. Playa: High-Performance Programmable Linear Algebra

    Directory of Open Access Journals (Sweden)

    Victoria E. Howle

    2012-01-01

    Full Text Available This paper introduces Playa, a high-level user interface layer for composing algorithms for complex multiphysics problems out of objects from other Trilinos packages. Among other features, Playa provides very high-performance overloaded operators implemented through an expression template mechanism. In this paper, we give an overview of the central Playa objects from a user's perspective, show application to a sequence of increasingly complex solver algorithms, provide timing results for Playa's overloaded operators and other functions, and briefly survey some of the implementation issues involved.

  3. High performance channel injection sealant invention abstract

    Science.gov (United States)

    Rosser, R. W.; Basiulis, D. I.; Salisbury, D. P. (Inventor)

    1982-01-01

    High performance channel sealant is based on NASA patented cyano and diamidoximine-terminated perfluoroalkylene ether prepolymers that are thermally condensed and cross linked. The sealant contains asbestos and, in its preferred embodiments, Lithofrax, to lower its thermal expansion coefficient and a phenolic metal deactivator. Extensive evaluation shows the sealant is extremely resistant to thermal degradation with an onset point of 280 C. The materials have a volatile content of 0.18%, excellent flexibility, and adherence properties, and fuel resistance. No corrosibility to aluminum or titanium was observed.

  4. Portability Support for High Performance Computing

    Science.gov (United States)

    Cheng, Doreen Y.; Cooper, D. M. (Technical Monitor)

    1994-01-01

    While a large number of tools have been developed to support application portability, high performance application developers often prefer to use vendor-provided, non-portable programming interfaces. This phenomena indicates the mismatch between user priorities and tool capabilities. This paper summarizes the results of a user survey and a developer survey. The user survey has revealed the user priorities and resulted in three criteria for evaluating tool support for portability. The developer survey has resulted in the evaluation of portability support and indicated the possibilities and difficulties of improvements.

  5. Prevalencias de sobrepeso y obesidad en niños y adolescentes de barrios con alto NBI de Puerto Madryn

    Directory of Open Access Journals (Sweden)

    Botterón, Tania Vanesa

    2005-01-01

    Full Text Available Estudios previos indican que Pto. Madryn presenta características de una población en transición nutricional, con bajos índices de desnutrición e incremento en la incidencia de sobrepeso infantil. En relación a ello en el presente trabajo se evalúa la prevalencia de sobrepeso y obesidad en niños y adolescentes de barrios con alto promedio de familias con NBI y valorados con tres referencias: NCHS, SAP-IOTF y Frisancho, 1991. Se relevaron peso, estatura total, pliegues subescapular y tricipital y se calculó el IMC en 656 niños de ambos sexos (6 a 16 años. El análisis de datos se realizó según las referencias indicadas para comparar sus valoraciones. Los resultados obtenidos hasta el presente muestran para ambos sexos un promedio de 60 a 75 % de valores de IMC normales, un 25 % de sobrepeso y entre un 3 a 7 % de obesidad Esto se relaciona con lo hallado por otros autores, por cuanto el sobrepeso y la obesidad son independientes de la condición socioeconómica de los individuos y, contar con datos actualizados y transferirlos a las entidades de aplicación correspondientes, redundarán en una disminución del riesgo de obesidad y de enfermedades crónicas no transmisibles (ECNT.

  6. Application of PLC to dynamic control system for liquid He cryogenic pumping facility on JT-60U NBI system

    Energy Technology Data Exchange (ETDEWEB)

    Honda, A. [Fusion Research and Development Directorate, Japan Atomic Energy Agency, 801-1 Mukouyayama, Naka-shi, Ibaraki-ken 311-0193 (Japan)], E-mail: honda.atsushi@jaea.go.jp; Okano, F.; Ooshima, K.; Akino, N.; Kikuchi, K.; Tanai, Y.; Takenouchi, T.; Numazawa, S.; Ikeda, Y. [Fusion Research and Development Directorate, Japan Atomic Energy Agency, 801-1 Mukouyayama, Naka-shi, Ibaraki-ken 311-0193 (Japan)

    2008-04-15

    The control system of the cryogenic facility in the JT-60 NBI system has been replaced by employing the PLC (Programmable Logic Controller) and SCADA (Supervisory Control And Data Acquisition) system. The original control system was constructed about 20 years ago by specifying the DCS (Distributed Control System) computer to deal with {approx}400 feedback loops. Recently, troubles on this control system have increased due to its age-induced deterioration. To maintain the high reliability of the cryogenic facility, a new control system has been planned with the PLC and SCADA systems. Their attractive features include high market availability and cost-effectiveness, however, the use of PLC for such a large facility with {approx}400 feedback loops has not been established because of insufficient processing capability of the early PLC. Meanwhile, the recent progress in the PLC enables to use the FBD (function block diagram) programming language for 500 function blocks. By optimizing the function blocks and connecting them in the FBD language, the feedback loops have been successfully replaced from DCS to PLC without a software developer. Moreover, an oscillation of the liquid He level, which often occurs during the cooldown mode of the cryopumps, can be automatically stabilized by easily adding a new process program in the PLC. At present, the new control system has worked well.

  7. Some aspects of the design of the ITER NBI Active Correction and Compensation Coils

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, Javier, E-mail: javier.alonso@ciemat.es [CIEMAT, Laboratorio Nacional de Fusión, Avda. Complutense 40, 28040 Madrid (Spain); Barrera, Germán; Cabrera, Santiago; Rincón, Esther; Ríos, Luis; Soleto, Alfonso [CIEMAT, Laboratorio Nacional de Fusión, Avda. Complutense 40, 28040 Madrid (Spain); El-Ouazzani, Anass; Graceffa, Joseph; Shah, Darshan; Urbani, Marc [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St Paul Lez Durance Cedex (France); Agarici, Gilbert [Fusion for Energy, Josep Pla 2, Torres Diagonal Litoral B3 – 07/08, 08019 Barcelona (Spain)

    2015-10-15

    Highlights: • Water cooled coil design. • Magnetic shielding of the plasma heating Neutral Beam Injection System. • Active coils for magnetic field compensation. - Abstract: The neutral beam system for ITER consists of two heating and current drive injectors plus a diagnostic neutral beam injector. The proposed physical plant layout allows for a possible third heating injector to be installed later. For correct operation of the beam source, and to avoid deflections of the charged fraction of the beam, the magnetic field along the beam path must be very low. To minimize the stray ITER field in critical areas (ion source, acceleration grids, neutralizer, residual ion dump), a Magnetic Field Reduction System will envelop the beam vessels and the high voltage transmission lines to ion source. This whole system comprises the Passive Magnetic Shield, a set of thick steel plates, and the Active Correction and Compensation Coils, a set of coils carrying currents which depend on the tokamak stray field. This paper describes the status of the coil design, terminals and support structures, as well as a description of the calculations carried out. Most coils are suitable for removal from their final position to be replaced in case of a fault. Conclusions of the chosen design highlight the strategy for the system feasibility.

  8. Strategy Guideline: Partnering for High Performance Homes

    Energy Technology Data Exchange (ETDEWEB)

    Prahl, D.

    2013-01-01

    High performance houses require a high degree of coordination and have significant interdependencies between various systems in order to perform properly, meet customer expectations, and minimize risks for the builder. Responsibility for the key performance attributes is shared across the project team and can be well coordinated through advanced partnering strategies. For high performance homes, traditional partnerships need to be matured to the next level and be expanded to all members of the project team including trades, suppliers, manufacturers, HERS raters, designers, architects, and building officials as appropriate. In an environment where the builder is the only source of communication between trades and consultants and where relationships are, in general, adversarial as opposed to cooperative, the chances of any one building system to fail are greater. Furthermore, it is much harder for the builder to identify and capitalize on synergistic opportunities. Partnering can help bridge the cross-functional aspects of the systems approach and achieve performance-based criteria. Critical success factors for partnering include support from top management, mutual trust, effective and open communication, effective coordination around common goals, team building, appropriate use of an outside facilitator, a partnering charter progress toward common goals, an effective problem-solving process, long-term commitment, continuous improvement, and a positive experience for all involved.

  9. High-performance computing for airborne applications

    Energy Technology Data Exchange (ETDEWEB)

    Quinn, Heather M [Los Alamos National Laboratory; Manuzzato, Andrea [Los Alamos National Laboratory; Fairbanks, Tom [Los Alamos National Laboratory; Dallmann, Nicholas [Los Alamos National Laboratory; Desgeorges, Rose [Los Alamos National Laboratory

    2010-06-28

    Recently, there has been attempts to move common satellite tasks to unmanned aerial vehicles (UAVs). UAVs are significantly cheaper to buy than satellites and easier to deploy on an as-needed basis. The more benign radiation environment also allows for an aggressive adoption of state-of-the-art commercial computational devices, which increases the amount of data that can be collected. There are a number of commercial computing devices currently available that are well-suited to high-performance computing. These devices range from specialized computational devices, such as field-programmable gate arrays (FPGAs) and digital signal processors (DSPs), to traditional computing platforms, such as microprocessors. Even though the radiation environment is relatively benign, these devices could be susceptible to single-event effects. In this paper, we will present radiation data for high-performance computing devices in a accelerated neutron environment. These devices include a multi-core digital signal processor, two field-programmable gate arrays, and a microprocessor. From these results, we found that all of these devices are suitable for many airplane environments without reliability problems.

  10. Building Trust in High-Performing Teams

    Directory of Open Access Journals (Sweden)

    Aki Soudunsaari

    2012-06-01

    Full Text Available Facilitation of growth is more about good, trustworthy contacts than capital. Trust is a driving force for business creation, and to create a global business you need to build a team that is capable of meeting the challenge. Trust is a key factor in team building and a needed enabler for cooperation. In general, trust building is a slow process, but it can be accelerated with open interaction and good communication skills. The fast-growing and ever-changing nature of global business sets demands for cooperation and team building, especially for startup companies. Trust building needs personal knowledge and regular face-to-face interaction, but it also requires empathy, respect, and genuine listening. Trust increases communication, and rich and open communication is essential for the building of high-performing teams. Other building materials are a shared vision, clear roles and responsibilities, willingness for cooperation, and supporting and encouraging leadership. This study focuses on trust in high-performing teams. It asks whether it is possible to manage trust and which tools and operation models should be used to speed up the building of trust. In this article, preliminary results from the authors’ research are presented to highlight the importance of sharing critical information and having a high level of communication through constant interaction.

  11. A Linux Workstation for High Performance Graphics

    Science.gov (United States)

    Geist, Robert; Westall, James

    2000-01-01

    The primary goal of this effort was to provide a low-cost method of obtaining high-performance 3-D graphics using an industry standard library (OpenGL) on PC class computers. Previously, users interested in doing substantial visualization or graphical manipulation were constrained to using specialized, custom hardware most often found in computers from Silicon Graphics (SGI). We provided an alternative to expensive SGI hardware by taking advantage of third-party, 3-D graphics accelerators that have now become available at very affordable prices. To make use of this hardware our goal was to provide a free, redistributable, and fully-compatible OpenGL work-alike library so that existing bodies of code could simply be recompiled. for PC class machines running a free version of Unix. This should allow substantial cost savings while greatly expanding the population of people with access to a serious graphics development and viewing environment. This should offer a means for NASA to provide a spectrum of graphics performance to its scientists, supplying high-end specialized SGI hardware for high-performance visualization while fulfilling the requirements of medium and lower performance applications with generic, off-the-shelf components and still maintaining compatibility between the two.

  12. Hybrid ventilation systems and high performance buildings

    Energy Technology Data Exchange (ETDEWEB)

    Utzinger, D.M. [Wisconsin Univ., Milwaukee, WI (United States). School of Architecture and Urban Planning

    2009-07-01

    This paper described hybrid ventilation design strategies and their impact on 3 high performance buildings located in southern Wisconsin. The Hybrid ventilation systems combined occupant controlled natural ventilation with mechanical ventilation systems. Natural ventilation was shown to provide adequate ventilation when appropriately designed. Proper control integration of natural ventilation into hybrid systems was shown to reduce energy consumption in high performance buildings. This paper also described the lessons learned from the 3 buildings. The author served as energy consultant on all three projects and had the responsibility of designing and integrating the natural ventilation systems into the HVAC control strategy. A post occupancy evaluation of building energy performance has provided learning material for architecture students. The 3 buildings included the Schlitz Audubon Nature Center completed in 2003; the Urban Ecology Center completed in 2004; and the Aldo Leopold Legacy Center completed in 2007. This paper included the size, measured energy utilization intensity and percentage of energy supplied by renewable solar power and bio-fuels on site for each building. 6 refs., 2 tabs., 6 figs.

  13. Management issues for high performance storage systems

    Energy Technology Data Exchange (ETDEWEB)

    Louis, S. [Lawrence Livermore National Lab., CA (United States); Burris, R. [Oak Ridge National Lab., TN (United States)

    1995-03-01

    Managing distributed high-performance storage systems is complex and, although sharing common ground with traditional network and systems management, presents unique storage-related issues. Integration technologies and frameworks exist to help manage distributed network and system environments. Industry-driven consortia provide open forums where vendors and users cooperate to leverage solutions. But these new approaches to open management fall short addressing the needs of scalable, distributed storage. We discuss the motivation and requirements for storage system management (SSM) capabilities and describe how SSM manages distributed servers and storage resource objects in the High Performance Storage System (HPSS), a new storage facility for data-intensive applications and large-scale computing. Modem storage systems, such as HPSS, require many SSM capabilities, including server and resource configuration control, performance monitoring, quality of service, flexible policies, file migration, file repacking, accounting, and quotas. We present results of initial HPSS SSM development including design decisions and implementation trade-offs. We conclude with plans for follow-on work and provide storage-related recommendations for vendors and standards groups seeking enterprise-wide management solutions.

  14. The path toward HEP High Performance Computing

    CERN Document Server

    Apostolakis, John; Carminati, Federico; Gheata, Andrei; Wenzel, Sandro

    2014-01-01

    High Energy Physics code has been known for making poor use of high performance computing architectures. Efforts in optimising HEP code on vector and RISC architectures have yield limited results and recent studies have shown that, on modern architectures, it achieves a performance between 10% and 50% of the peak one. Although several successful attempts have been made to port selected codes on GPUs, no major HEP code suite has a 'High Performance' implementation. With LHC undergoing a major upgrade and a number of challenging experiments on the drawing board, HEP cannot any longer neglect the less-than-optimal performance of its code and it has to try making the best usage of the hardware. This activity is one of the foci of the SFT group at CERN, which hosts, among others, the Root and Geant4 project. The activity of the experiments is shared and coordinated via a Concurrency Forum, where the experience in optimising HEP code is presented and discussed. Another activity is the Geant-V project, centred on th...

  15. Determination of trace elements in high pure rare earth oxide by double focusing inductively coupled plasma mass spectrometry (HR ICP-MS) and high performance liquid chromatography (HPLC) techniques; Determinacao de impurezas metalicas em oxidos de terras raras de alta pureza pela espectrometria de massa (setor magnetico) com fonte de plasma induzida por argonio (HR ICP-MS) e cromatografia liquida de alto desempenho (HPLC)

    Energy Technology Data Exchange (ETDEWEB)

    Pedreira Filho, Walter dos Reis

    2000-07-01

    Rare earth oxides are used in several technological fields whose applications can be observed in several areas of modern technology, among which are included: lasers, semiconductors semi, high purity materials and metallic alloys. The field of applications of the rare earth elements is quite wide. Several important industrial applications are ceramics, catalysts and metallurgical as well as research areas and high technology sectors. Such applications have been presenting an accentuated growth in the last years. Chemical characterization of rare earth oxides of high purity has been constituting one of the major challenges of analytical chemistry. Several analytical techniques were used for chemical characterization of high purity rare earth the oxides. Even so, those techniques present limitations when one needs to characterize materials of a high level of purity, as in the case of rare earth oxides. Some of those limitations are associated, for example, to spectral interference. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) is a powerful analytical tool for quantitative analysis of metal impurities in high purity materials. The Instituto de Pesquisas Energeticas e Nucleares (IPEN) has an unit of production and purification of rare earth oxides, with above 99,9% level of purity. In this work, the rare earth impurities were characterized in samples (La{sub 2}O{sub 3}; CeO{sub 2}; Pr{sub 6}O{sub 11}; Nd{sub 2}O{sub 3}; Sm{sub 2}O{sub 3}; Gd{sub 2}O{sub 3}; Y{sub 2}O{sub 3}) produced at the IPEN and certified standard materials produced by Johnson Matthey Chemical (JMC). The technique of high performance liquid chromatography (HPLC) was used in the separation of the impurities. Quantification of metallic impurities was carried out as inductively coupled plasma mass spectrometer (HR-ICP MS). In this work it is presented a new analytical methodology in the chemical characterization of metallic impurities in rare earth oxides of high purity (> 99,9%) with and

  16. Bioinspired phospholipid polymer biomaterials for making high performance artificial organs

    Directory of Open Access Journals (Sweden)

    K Ishihara

    2000-01-01

    Full Text Available Novel polymer biomaterials, which can be used in contact with blood, are prepared with strong inspiration from the surface structure of biomembrane. That is, the polymers with a phospholipid polar group in the side chain, 2-methacrylooyloxyethyl phosphorylcholine (MPC polymers were synthesized. The MPC polymers can inhibit surface-induced clot formation effectively, when they are in contact with blood even in the absence of an anticoagulant. This phenomenon was due to the reduction of plasma protein and suppression of denaturation of adsorbed proteins, that is the MPC polymers interact with blood components very mildly. As the molecular structure of the MPC polymer was easily designed by changing the monomer units and their composition, it could be applied to surface modification of artificial organs and biomedical devices for improving blood and tissue compatibility. Thus, the MPC polymers are useful polymer biomaterials for manufacturing high performance artificial organs and biomedical devices to provide safe medical treatments.

  17. Negative ion RF sources for ITER NBI: status of the development and recent achievements

    Energy Technology Data Exchange (ETDEWEB)

    Fantz, U; Franzen, P; Kraus, W; Berger, M; Christ-Koch, S; Froeschle, M; Gutser, R; Heinemann, B; Martens, C; McNeely, P; Riedl, R; Speth, E; Wuenderlich, D [Max-Planck-Insitut fuer Plasmaphysik, EURATOM Association, Boltzmannstrasse 2, D-85748 Garching (Germany)

    2007-12-15

    For heating and current drive the neutral beam injection system for ITER requires a deuterium beam with an energy of 1 MeV for up to 1 h. In order to inject the required 17 MW the ion source has to deliver 40 A of negative ion current. For an accelerated current density of 200 A m{sup -2} at the specified source pressure of 0.3 Pa the extraction area is 0.2 m{sup 2} resulting in a large area source of 1.5 x 0.6 m{sup 2}. Two types of sources have been under discussion, the filamented arc source and the inductively driven RF source, the latter now having been chosen for the ITER reference design. The development of negative ion RF sources, which fulfil these specifications is being carried out at the Max-Planck-Institut fuer Plasmaphysik at three test facilities in parallel. The required current densities at the ITER relevant pressure have been achieved and even exceeded in a test facility equipped with a small ion source (extraction area of 0.007 m{sup 2}) at limited pulse length (<4 s). The extraction area can be extended up to 0.03 m{sup 2} and the pulse length up to 3600 s at a second test facility which is dedicated to long pulse operation experiments where pulses up to 800 s have already been achieved. The ion source at the third test facility has roughly the full width and half the height of the ITER source but is not equipped with an extraction system. The aim is to demonstrate the size scaling and plasma homogeneity of RF ion sources. First results from different diagnostic techniques (optical emission spectroscopy and Langmuir probe) are very promising.

  18. How to create high-performing teams.

    Science.gov (United States)

    Lam, Samuel M

    2010-02-01

    This article is intended to discuss inspirational aspects on how to lead a high-performance team. Cogent topics discussed include how to hire staff through methods of "topgrading" with reference to Geoff Smart and "getting the right people on the bus" referencing Jim Collins' work. In addition, once the staff is hired, this article covers how to separate the "eagles from the ducks" and how to inspire one's staff by creating the right culture with suggestions for further reading by Don Miguel Ruiz (The four agreements) and John Maxwell (21 Irrefutable laws of leadership). In addition, Simon Sinek's concept of "Start with Why" is elaborated to help a leader know what the core element should be with any superior culture. Thieme Medical Publishers.

  19. Parallel Algebraic Multigrid Methods - High Performance Preconditioners

    Energy Technology Data Exchange (ETDEWEB)

    Yang, U M

    2004-11-11

    The development of high performance, massively parallel computers and the increasing demands of computationally challenging applications have necessitated the development of scalable solvers and preconditioners. One of the most effective ways to achieve scalability is the use of multigrid or multilevel techniques. Algebraic multigrid (AMG) is a very efficient algorithm for solving large problems on unstructured grids. While much of it can be parallelized in a straightforward way, some components of the classical algorithm, particularly the coarsening process and some of the most efficient smoothers, are highly sequential, and require new parallel approaches. This chapter presents the basic principles of AMG and gives an overview of various parallel implementations of AMG, including descriptions of parallel coarsening schemes and smoothers, some numerical results as well as references to existing software packages.

  20. A high performance microfabricated surface ion trap

    Science.gov (United States)

    Lobser, Daniel; Blain, Matthew; Haltli, Raymond; Hollowell, Andrew; Revelle, Melissa; Stick, Daniel; Yale, Christopher; Maunz, Peter

    2017-04-01

    Microfabricated surface ion traps present a natural solution to the problem of scalability in trapped ion quantum computing architectures. We address some of the chief concerns about surface ion traps by demonstrating low heating rates, long trapping times as well as other high-performance features of Sandia's high optical access (HOA-2) trap. For example, due to the HOA's specific electrode layout, we are able to rotate principal axes of the trapping potential from 0 to 2 π without any change in the secular trap frequencies. We have also achieved the first single-qubit gates with a diamond norm below a rigorous fault tolerance threshold, and a two-qubit Mølmer-Sørensen gate with a process fidelity of 99.58(6). Here we present specific details of trap capabilities, such as shuttling and ion reordering, as well as details of our high fidelity single- and two-qubit gates.

  1. High-Performance, Low Environmental Impact Refrigerants

    Science.gov (United States)

    McCullough, E. T.; Dhooge, P. M.; Glass, S. M.; Nimitz, J. S.

    2001-01-01

    Refrigerants used in process and facilities systems in the US include R-12, R-22, R-123, R-134a, R-404A, R-410A, R-500, and R-502. All but R-134a, R-404A, and R-410A contain ozone-depleting substances that will be phased out under the Montreal Protocol. Some of the substitutes do not perform as well as the refrigerants they are replacing, require new equipment, and have relatively high global warming potentials (GWPs). New refrigerants are needed that addresses environmental, safety, and performance issues simultaneously. In efforts sponsored by Ikon Corporation, NASA Kennedy Space Center (KSC), and the US Environmental Protection Agency (EPA), ETEC has developed and tested a new class of refrigerants, the Ikon (registered) refrigerants, based on iodofluorocarbons (IFCs). These refrigerants are nonflammable, have essentially zero ozone-depletion potential (ODP), low GWP, high performance (energy efficiency and capacity), and can be dropped into much existing equipment.

  2. High performance nano-composite technology development

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Whung Whoe; Rhee, C. K.; Kim, S. J.; Park, S. D. [KAERI, Taejon (Korea, Republic of); Kim, E. K.; Jung, S. Y.; Ryu, H. J. [KRICT, Taejon (Korea, Republic of); Hwang, S. S.; Kim, J. K.; Hong, S. M. [KIST, Taejon (Korea, Republic of); Chea, Y. B. [KIGAM, Taejon (Korea, Republic of); Choi, C. H.; Kim, S. D. [ATS, Taejon (Korea, Republic of); Cho, B. G.; Lee, S. H. [HGREC, Taejon (Korea, Republic of)

    1999-06-15

    The trend of new material development are being to carried out not only high performance but also environmental attraction. Especially nano composite material which enhances the functional properties of components, extending the component life resulting to reduced the wastes and environmental contamination, has a great effect on various industrial area. The application of nano composite, depends on the polymer matrix and filler materials, has various application from semiconductor to medical field. In spite of nano composite merits, nano composite study are confined to a few special materials as a lab, scale because a few technical difficulties are still on hold. Therefore, the purpose of this study establishes the systematical planning to carried out the next generation projects on order to compete with other countries and overcome the protective policy of advanced countries with grasping over sea's development trends and our present status. (author).

  3. High Performance Database Management for Earth Sciences

    Science.gov (United States)

    Rishe, Naphtali; Barton, David; Urban, Frank; Chekmasov, Maxim; Martinez, Maria; Alvarez, Elms; Gutierrez, Martha; Pardo, Philippe

    1998-01-01

    The High Performance Database Research Center at Florida International University is completing the development of a highly parallel database system based on the semantic/object-oriented approach. This system provides exceptional usability and flexibility. It allows shorter application design and programming cycles and gives the user control via an intuitive information structure. It empowers the end-user to pose complex ad hoc decision support queries. Superior efficiency is provided through a high level of optimization, which is transparent to the user. Manifold reduction in storage size is allowed for many applications. This system allows for operability via internet browsers. The system will be used for the NASA Applications Center program to store remote sensing data, as well as for Earth Science applications.

  4. High performance stepper motors for space mechanisms

    Science.gov (United States)

    Sega, Patrick; Estevenon, Christine

    1995-01-01

    Hybrid stepper motors are very well adapted to high performance space mechanisms. They are very simple to operate and are often used for accurate positioning and for smooth rotations. In order to fulfill these requirements, the motor torque, its harmonic content, and the magnetic parasitic torque have to be properly designed. Only finite element computations can provide enough accuracy to determine the toothed structures' magnetic permeance, whose derivative function leads to the torque. It is then possible to design motors with a maximum torque capability or with the most reduced torque harmonic content (less than 3 percent of fundamental). These later motors are dedicated to applications where a microstep or a synchronous mode is selected for minimal dynamic disturbances. In every case, the capability to convert electrical power into torque is much higher than on DC brushless motors.

  5. High performance computing applications in neurobiological research

    Science.gov (United States)

    Ross, Muriel D.; Cheng, Rei; Doshay, David G.; Linton, Samuel W.; Montgomery, Kevin; Parnas, Bruce R.

    1994-01-01

    The human nervous system is a massively parallel processor of information. The vast numbers of neurons, synapses and circuits is daunting to those seeking to understand the neural basis of consciousness and intellect. Pervading obstacles are lack of knowledge of the detailed, three-dimensional (3-D) organization of even a simple neural system and the paucity of large scale, biologically relevant computer simulations. We use high performance graphics workstations and supercomputers to study the 3-D organization of gravity sensors as a prototype architecture foreshadowing more complex systems. Scaled-down simulations run on a Silicon Graphics workstation and scale-up, three-dimensional versions run on the Cray Y-MP and CM5 supercomputers.

  6. High Performance OLED Panel and Luminaire

    Energy Technology Data Exchange (ETDEWEB)

    Spindler, Jeffrey [OLEDWorks LLC, Rochester, NY (United States)

    2017-02-20

    In this project, OLEDWorks developed and demonstrated the technology required to produce OLED lighting panels with high energy efficiency and excellent light quality. OLED panels developed in this program produce high quality warm white light with CRI greater than 85 and efficacy up to 80 lumens per watt (LPW). An OLED luminaire employing 24 of the high performance panels produces practical levels of illumination for general lighting, with a flux of over 2200 lumens at 60 LPW. This is a significant advance in the state of the art for OLED solid-state lighting (SSL), which is expected to be a complementary light source to the more advanced LED SSL technology that is rapidly replacing all other traditional forms of lighting.

  7. High performance anode for advanced Li batteries

    Energy Technology Data Exchange (ETDEWEB)

    Lake, Carla [Applied Sciences, Inc., Cedarville, OH (United States)

    2015-11-02

    The overall objective of this Phase I SBIR effort was to advance the manufacturing technology for ASI’s Si-CNF high-performance anode by creating a framework for large volume production and utilization of low-cost Si-coated carbon nanofibers (Si-CNF) for the battery industry. This project explores the use of nano-structured silicon which is deposited on a nano-scale carbon filament to achieve the benefits of high cycle life and high charge capacity without the consequent fading of, or failure in the capacity resulting from stress-induced fracturing of the Si particles and de-coupling from the electrode. ASI’s patented coating process distinguishes itself from others, in that it is highly reproducible, readily scalable and results in a Si-CNF composite structure containing 25-30% silicon, with a compositionally graded interface at the Si-CNF interface that significantly improve cycling stability and enhances adhesion of silicon to the carbon fiber support. In Phase I, the team demonstrated the production of the Si-CNF anode material can successfully be transitioned from a static bench-scale reactor into a fluidized bed reactor. In addition, ASI made significant progress in the development of low cost, quick testing methods which can be performed on silicon coated CNFs as a means of quality control. To date, weight change, density, and cycling performance were the key metrics used to validate the high performance anode material. Under this effort, ASI made strides to establish a quality control protocol for the large volume production of Si-CNFs and has identified several key technical thrusts for future work. Using the results of this Phase I effort as a foundation, ASI has defined a path forward to commercialize and deliver high volume and low-cost production of SI-CNF material for anodes in Li-ion batteries.

  8. PREFACE: High Performance Computing Symposium 2011

    Science.gov (United States)

    Talon, Suzanne; Mousseau, Normand; Peslherbe, Gilles; Bertrand, François; Gauthier, Pierre; Kadem, Lyes; Moitessier, Nicolas; Rouleau, Guy; Wittig, Rod

    2012-02-01

    HPCS (High Performance Computing Symposium) is a multidisciplinary conference that focuses on research involving High Performance Computing and its application. Attended by Canadian and international experts and renowned researchers in the sciences, all areas of engineering, the applied sciences, medicine and life sciences, mathematics, the humanities and social sciences, it is Canada's pre-eminent forum for HPC. The 25th edition was held in Montréal, at the Université du Québec à Montréal, from 15-17 June and focused on HPC in Medical Science. The conference was preceded by tutorials held at Concordia University, where 56 participants learned about HPC best practices, GPU computing, parallel computing, debugging and a number of high-level languages. 274 participants from six countries attended the main conference, which involved 11 invited and 37 contributed oral presentations, 33 posters, and an exhibit hall with 16 booths from our sponsors. The work that follows is a collection of papers presented at the conference covering HPC topics ranging from computer science to bioinformatics. They are divided here into four sections: HPC in Engineering, Physics and Materials Science, HPC in Medical Science, HPC Enabling to Explore our World and New Algorithms for HPC. We would once more like to thank the participants and invited speakers, the members of the Scientific Committee, the referees who spent time reviewing the papers and our invaluable sponsors. To hear the invited talks and learn about 25 years of HPC development in Canada visit the Symposium website: http://2011.hpcs.ca/lang/en/conference/keynote-speakers/ Enjoy the excellent papers that follow, and we look forward to seeing you in Vancouver for HPCS 2012! Gilles Peslherbe Chair of the Scientific Committee Normand Mousseau Co-Chair of HPCS 2011 Suzanne Talon Chair of the Organizing Committee UQAM Sponsors The PDF also contains photographs from the conference banquet.

  9. Wearable Accelerometers in High Performance Jet Aircraft.

    Science.gov (United States)

    Rice, G Merrill; VanBrunt, Thomas B; Snider, Dallas H; Hoyt, Robert E

    2016-02-01

    Wearable accelerometers have become ubiquitous in the fields of exercise physiology and ambulatory hospital settings. However, these devices have yet to be validated in extreme operational environments. The objective of this study was to correlate the gravitational forces (G forces) detected by wearable accelerometers with the G forces detected by high performance aircraft. We compared the in-flight G forces detected by the two commercially available portable accelerometers to the F/A-18 Carrier Aircraft Inertial Navigation System (CAINS-2) during 20 flights performed by the Navy's Flight Demonstration Squadron (Blue Angels). Postflight questionnaires were also used to assess the perception of distractibility during flight. Of the 20 flights analyzed, 10 complete in-flight comparisons were made, accounting for 25,700 s of correlation between the CAINS-2 and the two tested accelerometers. Both accelerometers had strong correlations with that of the F/A-18 Gz axis, averaging r = 0.92 and r = 0.93, respectively, over 10 flights. Comparison of both portable accelerometer's average vector magnitude to each other yielded an average correlation of r = 0.93. Both accelerometers were found to be minimally distracting. These results suggest the use of wearable accelerometers is a valid means of detecting G forces during high performance aircraft flight. Future studies using this surrogate method of detecting accelerative forces combined with physiological information may yield valuable in-flight normative data that heretofore has been technically difficult to obtain and hence holds the promise of opening the door for a new golden age of aeromedical research.

  10. SISYPHUS: A high performance seismic inversion factory

    Science.gov (United States)

    Gokhberg, Alexey; Simutė, Saulė; Boehm, Christian; Fichtner, Andreas

    2016-04-01

    In the recent years the massively parallel high performance computers became the standard instruments for solving the forward and inverse problems in seismology. The respective software packages dedicated to forward and inverse waveform modelling specially designed for such computers (SPECFEM3D, SES3D) became mature and widely available. These packages achieve significant computational performance and provide researchers with an opportunity to solve problems of bigger size at higher resolution within a shorter time. However, a typical seismic inversion process contains various activities that are beyond the common solver functionality. They include management of information on seismic events and stations, 3D models, observed and synthetic seismograms, pre-processing of the observed signals, computation of misfits and adjoint sources, minimization of misfits, and process workflow management. These activities are time consuming, seldom sufficiently automated, and therefore represent a bottleneck that can substantially offset performance benefits provided by even the most powerful modern supercomputers. Furthermore, a typical system architecture of modern supercomputing platforms is oriented towards the maximum computational performance and provides limited standard facilities for automation of the supporting activities. We present a prototype solution that automates all aspects of the seismic inversion process and is tuned for the modern massively parallel high performance computing systems. We address several major aspects of the solution architecture, which include (1) design of an inversion state database for tracing all relevant aspects of the entire solution process, (2) design of an extensible workflow management framework, (3) integration with wave propagation solvers, (4) integration with optimization packages, (5) computation of misfits and adjoint sources, and (6) process monitoring. The inversion state database represents a hierarchical structure with

  11. NCI's Transdisciplinary High Performance Scientific Data Platform

    Science.gov (United States)

    Evans, Ben; Antony, Joseph; Bastrakova, Irina; Car, Nicholas; Cox, Simon; Druken, Kelsey; Evans, Bradley; Fraser, Ryan; Ip, Alex; Kemp, Carina; King, Edward; Minchin, Stuart; Larraondo, Pablo; Pugh, Tim; Richards, Clare; Santana, Fabiana; Smillie, Jon; Trenham, Claire; Wang, Jingbo; Wyborn, Lesley

    2016-04-01

    The Australian National Computational Infrastructure (NCI) manages Earth Systems data collections sourced from several domains and organisations onto a single High Performance Data (HPD) Node to further Australia's national priority research and innovation agenda. The NCI HPD Node has rapidly established its value, currently managing over 10 PBytes of datasets from collections that span a wide range of disciplines including climate, weather, environment, geoscience, geophysics, water resources and social sciences. Importantly, in order to facilitate broad user uptake, maximise reuse and enable transdisciplinary access through software and standardised interfaces, the datasets, associated information systems and processes have been incorporated into the design and operation of a unified platform that NCI has called, the National Environmental Research Data Interoperability Platform (NERDIP). The key goal of the NERDIP is to regularise data access so that it is easily discoverable, interoperable for different domains and enabled for high performance methods. It adopts and implements international standards and data conventions, and promotes scientific integrity within a high performance computing and data analysis environment. NCI has established a rich and flexible computing environment to access to this data, through the NCI supercomputer; a private cloud that supports both domain focused virtual laboratories and in-common interactive analysis interfaces; as well as remotely through scalable data services. Data collections of this importance must be managed with careful consideration of both their current use and the needs of the end-communities, as well as its future potential use, such as transitioning to more advanced software and improved methods. It is therefore critical that the data platform is both well-managed and trusted for stable production use (including transparency and reproducibility), agile enough to incorporate new technological advances and

  12. A high performance field-reversed configuration

    Energy Technology Data Exchange (ETDEWEB)

    Binderbauer, M. W.; Tajima, T.; Steinhauer, L. C.; Garate, E.; Tuszewski, M.; Smirnov, A.; Gota, H.; Barnes, D.; Deng, B. H.; Thompson, M. C.; Trask, E.; Yang, X.; Putvinski, S.; Rostoker, N.; Andow, R.; Aefsky, S.; Bolte, N.; Bui, D. Q.; Ceccherini, F.; Clary, R. [Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688 (United States); and others

    2015-05-15

    Conventional field-reversed configurations (FRCs), high-beta, prolate compact toroids embedded in poloidal magnetic fields, face notable stability and confinement concerns. These can be ameliorated by various control techniques, such as introducing a significant fast ion population. Indeed, adding neutral beam injection into the FRC over the past half-decade has contributed to striking improvements in confinement and stability. Further, the addition of electrically biased plasma guns at the ends, magnetic end plugs, and advanced surface conditioning led to dramatic reductions in turbulence-driven losses and greatly improved stability. Together, these enabled the build-up of a well-confined and dominant fast-ion population. Under such conditions, highly reproducible, macroscopically stable hot FRCs (with total plasma temperature of ∼1 keV) with record lifetimes were achieved. These accomplishments point to the prospect of advanced, beam-driven FRCs as an intriguing path toward fusion reactors. This paper reviews key results and presents context for further interpretation.

  13. Materials for high performance light water reactors

    Science.gov (United States)

    Ehrlich, K.; Konys, J.; Heikinheimo, L.

    2004-05-01

    A state-of-the-art study was performed to investigate the operational conditions for in-core and out-of-core materials in a high performance light water reactor (HPLWR) and to evaluate the potential of existing structural materials for application in fuel elements, core structures and out-of-core components. In the conventional parts of a HPLWR-plant the approved materials of supercritical fossil power plants (SCFPP) can be used for given temperatures (⩽600 °C) and pressures (≈250 bar). These are either commercial ferritic/martensitic or austenitic stainless steels. Taking the conditions of existing light water reactors (LWR) into account an assessment of potential cladding materials was made, based on existing creep-rupture data, an extensive analysis of the corrosion in conventional steam power plants and available information on material behaviour under irradiation. As a major result it is shown that for an assumed maximum temperature of 650 °C not only Ni-alloys, but also austenitic stainless steels can be used as cladding materials.

  14. High performance hand-held gas chromatograph

    Energy Technology Data Exchange (ETDEWEB)

    Yu, C.M.

    1998-04-28

    The Microtechnology Center of Lawrence Livermore National Laboratory has developed a high performance hand-held, real time detection gas chromatograph (HHGC) by Micro-Electro-Mechanical-System (MEMS) technology. The total weight of this hand-held gas chromatograph is about five lbs., with a physical size of 8{close_quotes} x 5{close_quotes} x 3{close_quotes} including carrier gas and battery. It consumes about 12 watts of electrical power with a response time on the order of one to two minutes. This HHGC has an average effective theoretical plate of about 40k. Presently, its sensitivity is limited by its thermal sensitive detector at PPM. Like a conventional G.C., this HHGC consists mainly of three major components: (1) the sample injector, (2) the column, and (3) the detector with related electronics. The present HHGC injector is a modified version of the conventional injector. Its separation column is fabricated completely on silicon wafers by means of MEMS technology. This separation column has a circular cross section with a diameter of 100 pm. The detector developed for this hand-held GC is a thermal conductivity detector fabricated on a silicon nitride window by MEMS technology. A normal Wheatstone bridge is used. The signal is fed into a PC and displayed through LabView software.

  15. Optimizing High Performance Self Compacting Concrete

    Directory of Open Access Journals (Sweden)

    Raymond A Yonathan

    2017-01-01

    Full Text Available This paper’s objectives are to learn the effect of glass powder, silica fume, Polycarboxylate Ether, and gravel to optimizing composition of each factor in making High Performance SCC. Taguchi method is proposed in this paper as best solution to minimize specimen variable which is more than 80 variations. Taguchi data analysis method is applied to provide composition, optimizing, and the effect of contributing materials for nine variable of specimens. Concrete’s workability was analyzed using Slump flow test, V-funnel test, and L-box test. Compressive and porosity test were performed for the hardened state. With a dimension of 100×200 mm the cylindrical specimens were cast for compressive test with the age of 3, 7, 14, 21, 28 days. Porosity test was conducted at 28 days. It is revealed that silica fume contributes greatly to slump flow and porosity. Coarse aggregate shows the greatest contributing factor to L-box and compressive test. However, all factors show unclear result to V-funnel test.

  16. Automatic Energy Schemes for High Performance Applications

    Energy Technology Data Exchange (ETDEWEB)

    Sundriyal, Vaibhav [Iowa State Univ., Ames, IA (United States)

    2013-01-01

    Although high-performance computing traditionally focuses on the efficient execution of large-scale applications, both energy and power have become critical concerns when approaching exascale. Drastic increases in the power consumption of supercomputers affect significantly their operating costs and failure rates. In modern microprocessor architectures, equipped with dynamic voltage and frequency scaling (DVFS) and CPU clock modulation (throttling), the power consumption may be controlled in software. Additionally, network interconnect, such as Infiniband, may be exploited to maximize energy savings while the application performance loss and frequency switching overheads must be carefully balanced. This work first studies two important collective communication operations, all-to-all and allgather and proposes energy saving strategies on the per-call basis. Next, it targets point-to-point communications to group them into phases and apply frequency scaling to them to save energy by exploiting the architectural and communication stalls. Finally, it proposes an automatic runtime system which combines both collective and point-to-point communications into phases, and applies throttling to them apart from DVFS to maximize energy savings. The experimental results are presented for NAS parallel benchmark problems as well as for the realistic parallel electronic structure calculations performed by the widely used quantum chemistry package GAMESS. Close to the maximum energy savings were obtained with a substantially low performance loss on the given platform.

  17. Development of a High Performance Spacer Grid

    Energy Technology Data Exchange (ETDEWEB)

    Song, Kee Nam; Song, K. N.; Yoon, K. H. (and others)

    2007-03-15

    A spacer grid in a LWR fuel assembly is a key structural component to support fuel rods and to enhance the heat transfer from the fuel rod to the coolant. In this research, the main research items are the development of inherent and high performance spacer grid shapes, the establishment of mechanical/structural analysis and test technology, and the set-up of basic test facilities for the spacer grid. The main research areas and results are as follows. 1. 18 different spacer grid candidates have been invented and applied for domestic and US patents. Among the candidates 16 are chosen from the patent. 2. Two kinds of spacer grids are finally selected for the advanced LWR fuel after detailed performance tests on the candidates and commercial spacer grids from a mechanical/structural point of view. According to the test results the features of the selected spacer grids are better than those of the commercial spacer grids. 3. Four kinds of basic test facilities are set up and the relevant test technologies are established. 4. Mechanical/structural analysis models and technology for spacer grid performance are developed and the analysis results are compared with the test results to enhance the reliability of the models.

  18. Initial rheological description of high performance concretes

    Directory of Open Access Journals (Sweden)

    Alessandra Lorenzetti de Castro

    2006-12-01

    Full Text Available Concrete is defined as a composite material and, in rheological terms, it can be understood as a concentrated suspension of solid particles (aggregates in a viscous liquid (cement paste. On a macroscopic scale, concrete flows as a liquid. It is known that the rheological behavior of the concrete is close to that of a Bingham fluid and two rheological parameters regarding its description are needed: yield stress and plastic viscosity. The aim of this paper is to present the initial rheological description of high performance concretes using the modified slump test. According to the results, an increase of yield stress was observed over time, while a slight variation in plastic viscosity was noticed. The incorporation of silica fume showed changes in the rheological properties of fresh concrete. The behavior of these materials also varied with the mixing procedure employed in their production. The addition of superplasticizer meant that there was a large reduction in the mixture's yield stress, while plastic viscosity remained practically constant.

  19. High Performance Graphene Oxide Based Rubber Composites

    Science.gov (United States)

    Mao, Yingyan; Wen, Shipeng; Chen, Yulong; Zhang, Fazhong; Panine, Pierre; Chan, Tung W.; Zhang, Liqun; Liang, Yongri; Liu, Li

    2013-08-01

    In this paper, graphene oxide/styrene-butadiene rubber (GO/SBR) composites with complete exfoliation of GO sheets were prepared by aqueous-phase mixing of GO colloid with SBR latex and a small loading of butadiene-styrene-vinyl-pyridine rubber (VPR) latex, followed by their co-coagulation. During co-coagulation, VPR not only plays a key role in the prevention of aggregation of GO sheets but also acts as an interface-bridge between GO and SBR. The results demonstrated that the mechanical properties of the GO/SBR composite with 2.0 vol.% GO is comparable with those of the SBR composite reinforced with 13.1 vol.% of carbon black (CB), with a low mass density and a good gas barrier ability to boot. The present work also showed that GO-silica/SBR composite exhibited outstanding wear resistance and low-rolling resistance which make GO-silica/SBR very competitive for the green tire application, opening up enormous opportunities to prepare high performance rubber composites for future engineering applications.

  20. High Performance Graphene Oxide Based Rubber Composites

    Science.gov (United States)

    Mao, Yingyan; Wen, Shipeng; Chen, Yulong; Zhang, Fazhong; Panine, Pierre; Chan, Tung W.; Zhang, Liqun; Liang, Yongri; Liu, Li

    2013-01-01

    In this paper, graphene oxide/styrene-butadiene rubber (GO/SBR) composites with complete exfoliation of GO sheets were prepared by aqueous-phase mixing of GO colloid with SBR latex and a small loading of butadiene-styrene-vinyl-pyridine rubber (VPR) latex, followed by their co-coagulation. During co-coagulation, VPR not only plays a key role in the prevention of aggregation of GO sheets but also acts as an interface-bridge between GO and SBR. The results demonstrated that the mechanical properties of the GO/SBR composite with 2.0 vol.% GO is comparable with those of the SBR composite reinforced with 13.1 vol.% of carbon black (CB), with a low mass density and a good gas barrier ability to boot. The present work also showed that GO-silica/SBR composite exhibited outstanding wear resistance and low-rolling resistance which make GO-silica/SBR very competitive for the green tire application, opening up enormous opportunities to prepare high performance rubber composites for future engineering applications. PMID:23974435

  1. Design of high performance CMC brake discs

    Energy Technology Data Exchange (ETDEWEB)

    Krenkel, W.; Henke, T. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Stuttgart (Germany)

    1999-03-01

    Ceramic matrix composite (CMC) materials based on 2D-carbon fibre preforms show high heat-absorption capacities and good tribological as well as thermomechanical properties. To take advantage of the full lightweight potential of these new materials in high performance automotive brake discs, the thermal conductivity transverse to the friction surface has to be high in order to reduce the surface temperature. Experimental tests showed, that lower surface temperatures prevent overheating of the brake`s periphery and stabilizes the friction behaviour. In this study different design approaches with improved transverse heat conductivity have been investigated by finite element analysis. C/C-SiC bolts as well as SiC coatings and combinations of them have been investigated and compared with an orthotropic brake disc, showing a reduction of temperature of up to 50%. Original sized brake discs with C/C-SiC have been manufactured and tested under real conditions which verified the calculations. Using only low-cost CMC materials and avoiding any additional processing steps, the potential of C/C-SiC brake discs are very attractive under tribological as well as under economical aspects. (orig.) 4 refs.

  2. 24 CFR 902.71 - Incentives for high performers.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Incentives for high performers. 902... DEVELOPMENT PUBLIC HOUSING ASSESSMENT SYSTEM PHAS Incentives and Remedies § 902.71 Incentives for high performers. (a) Incentives for high performer PHAs. A PHA that is designated a high performer will be...

  3. High-performance phase-field modeling

    KAUST Repository

    Vignal, Philippe

    2015-04-27

    Many processes in engineering and sciences involve the evolution of interfaces. Among the mathematical frameworks developed to model these types of problems, the phase-field method has emerged as a possible solution. Phase-fields nonetheless lead to complex nonlinear, high-order partial differential equations, whose solution poses mathematical and computational challenges. Guaranteeing some of the physical properties of the equations has lead to the development of efficient algorithms and discretizations capable of recovering said properties by construction [2, 5]. This work builds-up on these ideas, and proposes novel discretization strategies that guarantee numerical energy dissipation for both conserved and non-conserved phase-field models. The temporal discretization is based on a novel method which relies on Taylor series and ensures strong energy stability. It is second-order accurate, and can also be rendered linear to speed-up the solution process [4]. The spatial discretization relies on Isogeometric Analysis, a finite element method that possesses the k-refinement technology and enables the generation of high-order, high-continuity basis functions. These basis functions are well suited to handle the high-order operators present in phase-field models. Two-dimensional and three dimensional results of the Allen-Cahn, Cahn-Hilliard, Swift-Hohenberg and phase-field crystal equation will be presented, which corroborate the theoretical findings, and illustrate the robustness of the method. Results related to more challenging examples, namely the Navier-Stokes Cahn-Hilliard and a diusion-reaction Cahn-Hilliard system, will also be presented. The implementation was done in PetIGA and PetIGA-MF, high-performance Isogeometric Analysis frameworks [1, 3], designed to handle non-linear, time-dependent problems.

  4. Scalable resource management in high performance computers.

    Energy Technology Data Exchange (ETDEWEB)

    Frachtenberg, E. (Eitan); Petrini, F. (Fabrizio); Fernandez Peinador, J. (Juan); Coll, S. (Salvador)

    2002-01-01

    Clusters of workstations have emerged as an important platform for building cost-effective, scalable and highly-available computers. Although many hardware solutions are available today, the largest challenge in making large-scale clusters usable lies in the system software. In this paper we present STORM, a resource management tool designed to provide scalability, low overhead and the flexibility necessary to efficiently support and analyze a wide range of job scheduling algorithms. STORM achieves these feats by closely integrating the management daemons with the low-level features that are common in state-of-the-art high-performance system area networks. The architecture of STORM is based on three main technical innovations. First, a sizable part of the scheduler runs in the thread processor located on the network interface. Second, we use hardware collectives that are highly scalable both for implementing control heartbeats and to distribute the binary of a parallel job in near-constant time, irrespective of job and machine sizes. Third, we use an I/O bypass protocol that allows fast data movements from the file system to the communication buffers in the network interface and vice versa. The experimental results show that STORM can launch a job with a binary of 12MB on a 64 processor/32 node cluster in less than 0.25 sec on an empty network, in less than 0.45 sec when all the processors are busy computing other jobs, and in less than 0.65 sec when the network is flooded with a background traffic. This paper provides experimental and analytical evidence that these results scale to a much larger number of nodes. To the best of our knowledge, STORM is at least two orders of magnitude faster than existing production schedulers in launching jobs, performing resource management tasks and gang scheduling.

  5. High-performance laboratories and cleanrooms

    Energy Technology Data Exchange (ETDEWEB)

    Tschudi, William; Sartor, Dale; Mills, Evan; Xu, Tengfang

    2002-07-01

    The California Energy Commission sponsored this roadmap to guide energy efficiency research and deployment for high performance cleanrooms and laboratories. Industries and institutions utilizing these building types (termed high-tech buildings) have played an important part in the vitality of the California economy. This roadmap's key objective to present a multi-year agenda to prioritize and coordinate research efforts. It also addresses delivery mechanisms to get the research products into the market. Because of the importance to the California economy, it is appropriate and important for California to take the lead in assessing the energy efficiency research needs, opportunities, and priorities for this market. In addition to the importance to California's economy, energy demand for this market segment is large and growing (estimated at 9400 GWH for 1996, Mills et al. 1996). With their 24hr. continuous operation, high tech facilities are a major contributor to the peak electrical demand. Laboratories and cleanrooms constitute the high tech building market, and although each building type has its unique features, they are similar in that they are extremely energy intensive, involve special environmental considerations, have very high ventilation requirements, and are subject to regulations--primarily safety driven--that tend to have adverse energy implications. High-tech buildings have largely been overlooked in past energy efficiency research. Many industries and institutions utilize laboratories and cleanrooms. As illustrated, there are many industries operating cleanrooms in California. These include semiconductor manufacturing, semiconductor suppliers, pharmaceutical, biotechnology, disk drive manufacturing, flat panel displays, automotive, aerospace, food, hospitals, medical devices, universities, and federal research facilities.

  6. Flow simulation and high performance computing

    Science.gov (United States)

    Tezduyar, T.; Aliabadi, S.; Behr, M.; Johnson, A.; Kalro, V.; Litke, M.

    1996-10-01

    Flow simulation is a computational tool for exploring science and technology involving flow applications. It can provide cost-effective alternatives or complements to laboratory experiments, field tests and prototyping. Flow simulation relies heavily on high performance computing (HPC). We view HPC as having two major components. One is advanced algorithms capable of accurately simulating complex, real-world problems. The other is advanced computer hardware and networking with sufficient power, memory and bandwidth to execute those simulations. While HPC enables flow simulation, flow simulation motivates development of novel HPC techniques. This paper focuses on demonstrating that flow simulation has come a long way and is being applied to many complex, real-world problems in different fields of engineering and applied sciences, particularly in aerospace engineering and applied fluid mechanics. Flow simulation has come a long way because HPC has come a long way. This paper also provides a brief review of some of the recently-developed HPC methods and tools that has played a major role in bringing flow simulation where it is today. A number of 3D flow simulations are presented in this paper as examples of the level of computational capability reached with recent HPC methods and hardware. These examples are, flow around a fighter aircraft, flow around two trains passing in a tunnel, large ram-air parachutes, flow over hydraulic structures, contaminant dispersion in a model subway station, airflow past an automobile, multiple spheres falling in a liquid-filled tube, and dynamics of a paratrooper jumping from a cargo aircraft.

  7. Integrating advanced facades into high performance buildings

    Energy Technology Data Exchange (ETDEWEB)

    Selkowitz, Stephen E.

    2001-05-01

    Glass is a remarkable material but its functionality is significantly enhanced when it is processed or altered to provide added intrinsic capabilities. The overall performance of glass elements in a building can be further enhanced when they are designed to be part of a complete facade system. Finally the facade system delivers the greatest performance to the building owner and occupants when it becomes an essential element of a fully integrated building design. This presentation examines the growing interest in incorporating advanced glazing elements into more comprehensive facade and building systems in a manner that increases comfort, productivity and amenity for occupants, reduces operating costs for building owners, and contributes to improving the health of the planet by reducing overall energy use and negative environmental impacts. We explore the role of glazing systems in dynamic and responsive facades that provide the following functionality: Enhanced sun protection and cooling load control while improving thermal comfort and providing most of the light needed with daylighting; Enhanced air quality and reduced cooling loads using natural ventilation schemes employing the facade as an active air control element; Reduced operating costs by minimizing lighting, cooling and heating energy use by optimizing the daylighting-thermal tradeoffs; Net positive contributions to the energy balance of the building using integrated photovoltaic systems; Improved indoor environments leading to enhanced occupant health, comfort and performance. In addressing these issues facade system solutions must, of course, respect the constraints of latitude, location, solar orientation, acoustics, earthquake and fire safety, etc. Since climate and occupant needs are dynamic variables, in a high performance building the facade solution have the capacity to respond and adapt to these variable exterior conditions and to changing occupant needs. This responsive performance capability

  8. Toward high performance in Powder Metallurgy

    Directory of Open Access Journals (Sweden)

    Torralba, José M.

    2014-06-01

    Full Text Available Powder Metallurgy (PM is technology well known for mass production of parts at low cost but usually with worse mechanical properties than same parts obtained by alternative routes. But using this technology, high performance materials can be obtained, depending of the processing route and the type and amount of porosity. In this paper, a brief review of the capabilities of powder technology is made with the objective of attaining the highest level of mechanical and physical properties. For this purpose, different strategies over the processing can be chosen: to act over the density/porosity level and properties of the pores, to act over strengthening mechanisms apart from the density of the material (the alloying system, the microstructure, the grain size,.., to improve the sintering activity by different routes and to use techniques that avoid the grain growth during sintering.La Pulvimetalurgia es una tecnología bien conocida por su faceta de producir piezas de forma masiva a bajo coste, pero habitualmente con una pérdida de propiedades mecánicas si se la compara con tecnologías alternativas para obtener las mismas piezas. Sin embargo, mediante esta tecnología, también se pueden obtener piezas de altas prestaciones, dependiendo de la ruta de procesado y del nivel de porosidad. En este trabajo, se realiza una sucinta revisión de las posibilidades de la tecnología de polvos que permitirían obtener los mayores niveles de prestaciones en cuanto a propiedades mecánicas y físicas. Se pueden elegir distintas estrategias en el procesado: actuar sobre el nivel de densidad/porosidad y las propiedades de los poros, actuar sobre mecanismos de endurecimiento distintos a la densidad (el sistema de aleación, la microestructura, el tamaño de grano,…, mejorar la activación durante la sinterización y utilizar técnicas que inhiban el tamaño de grano durante la sinterización.

  9. High Performance Commercial Fenestration Framing Systems

    Energy Technology Data Exchange (ETDEWEB)

    Mike Manteghi; Sneh Kumar; Joshua Early; Bhaskar Adusumalli

    2010-01-31

    A major objective of the U.S. Department of Energy is to have a zero energy commercial building by the year 2025. Windows have a major influence on the energy performance of the building envelope as they control over 55% of building energy load, and represent one important area where technologies can be developed to save energy. Aluminum framing systems are used in over 80% of commercial fenestration products (i.e. windows, curtain walls, store fronts, etc.). Aluminum framing systems are often required in commercial buildings because of their inherent good structural properties and long service life, which is required from commercial and architectural frames. At the same time, they are lightweight and durable, requiring very little maintenance, and offer design flexibility. An additional benefit of aluminum framing systems is their relatively low cost and easy manufacturability. Aluminum, being an easily recyclable material, also offers sustainable features. However, from energy efficiency point of view, aluminum frames have lower thermal performance due to the very high thermal conductivity of aluminum. Fenestration systems constructed of aluminum alloys therefore have lower performance in terms of being effective barrier to energy transfer (heat loss or gain). Despite the lower energy performance, aluminum is the choice material for commercial framing systems and dominates the commercial/architectural fenestration market because of the reasons mentioned above. In addition, there is no other cost effective and energy efficient replacement material available to take place of aluminum in the commercial/architectural market. Hence it is imperative to improve the performance of aluminum framing system to improve the energy performance of commercial fenestration system and in turn reduce the energy consumption of commercial building and achieve zero energy building by 2025. The objective of this project was to develop high performance, energy efficient commercial

  10. High Performance Computing in Science and Engineering '17 : Transactions of the High Performance Computing Center

    CERN Document Server

    Kröner, Dietmar; Resch, Michael; HLRS 2017

    2018-01-01

    This book presents the state-of-the-art in supercomputer simulation. It includes the latest findings from leading researchers using systems from the High Performance Computing Center Stuttgart (HLRS) in 2017. The reports cover all fields of computational science and engineering ranging from CFD to computational physics and from chemistry to computer science with a special emphasis on industrially relevant applications. Presenting findings of one of Europe’s leading systems, this volume covers a wide variety of applications that deliver a high level of sustained performance.The book covers the main methods in high-performance computing. Its outstanding results in achieving the best performance for production codes are of particular interest for both scientists and engineers. The book comes with a wealth of color illustrations and tables of results.

  11. High Performance Computing in Science and Engineering '15 : Transactions of the High Performance Computing Center

    CERN Document Server

    Kröner, Dietmar; Resch, Michael

    2016-01-01

    This book presents the state-of-the-art in supercomputer simulation. It includes the latest findings from leading researchers using systems from the High Performance Computing Center Stuttgart (HLRS) in 2015. The reports cover all fields of computational science and engineering ranging from CFD to computational physics and from chemistry to computer science with a special emphasis on industrially relevant applications. Presenting findings of one of Europe’s leading systems, this volume covers a wide variety of applications that deliver a high level of sustained performance. The book covers the main methods in high-performance computing. Its outstanding results in achieving the best performance for production codes are of particular interest for both scientists and engineers. The book comes with a wealth of color illustrations and tables of results.

  12. Intelligent Facades for High Performance Green Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Dyson, Anna [Rensselaer Polytechnic Inst., Troy, NY (United States)

    2017-03-01

    Progress Towards Net-Zero and Net-Positive-Energy Commercial Buildings and Urban Districts Through Intelligent Building Envelope Strategies Previous research and development of intelligent facades systems has been limited in their contribution towards national goals for achieving on-site net zero buildings, because this R&D has failed to couple the many qualitative requirements of building envelopes such as the provision of daylighting, access to exterior views, satisfying aesthetic and cultural characteristics, with the quantitative metrics of energy harvesting, storage and redistribution. To achieve energy self-sufficiency from on-site solar resources, building envelopes can and must address this gamut of concerns simultaneously. With this project, we have undertaken a high-performance building integrated combined-heat and power concentrating photovoltaic system with high temperature thermal capture, storage and transport towards multiple applications (BICPV/T). The critical contribution we are offering with the Integrated Concentrating Solar Façade (ICSF) is conceived to improve daylighting quality for improved health of occupants and mitigate solar heat gain while maximally capturing and transferring onsite solar energy. The ICSF accomplishes this multi-functionality by intercepting only the direct-normal component of solar energy (which is responsible for elevated cooling loads) thereby transforming a previously problematic source of energy into a high quality resource that can be applied to building demands such as heating, cooling, dehumidification, domestic hot water, and possible further augmentation of electrical generation through organic Rankine cycles. With the ICSF technology, our team is addressing the global challenge in transitioning commercial and residential building stock towards on-site clean energy self-sufficiency, by fully integrating innovative environmental control systems strategies within an intelligent and responsively dynamic building

  13. Long-range correlations during plasma transitions in the TJ-II stellarator

    Energy Technology Data Exchange (ETDEWEB)

    Pedrosa, M.A.; Carreras, B.A.; Carralero, D. [Laboratorio Nacional de Fusion, Asociacion EURATOM-CIEMAT, Madrid (Spain); Hidalgo, C. [Associacaeo EURATOM-IST, Centro de Fusaeo Nuclear, Lisboa (Portugal); Silva, C. [Departamento de Fisica, Universidad Carlos III, Madrid (Spain); Calvo, I.

    2010-08-15

    The mechanism underlying the development of edge transport barriers is still one of the fundamental issues con-fronting the magnetic fusion community. The results presented show the importance of long-range correlation as approaching plasma bifurcations in different plasma scenarios, including biasing induced and spontaneous edge transport bifurcations in ECRH and NBI plasmas. These findings are consistent with the theory of zonal flows, pointing out the importance of both mean and fluctuating electric fields during the development of edge plasma transitions. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  14. High-performance commercial building systems

    Energy Technology Data Exchange (ETDEWEB)

    Selkowitz, Stephen

    2003-10-01

    This report summarizes key technical accomplishments resulting from the three year PIER-funded R&D program, ''High Performance Commercial Building Systems'' (HPCBS). The program targets the commercial building sector in California, an end-use sector that accounts for about one-third of all California electricity consumption and an even larger fraction of peak demand, at a cost of over $10B/year. Commercial buildings also have a major impact on occupant health, comfort and productivity. Building design and operations practices that influence energy use are deeply engrained in a fragmented, risk-averse industry that is slow to change. Although California's aggressive standards efforts have resulted in new buildings designed to use less energy than those constructed 20 years ago, the actual savings realized are still well below technical and economic potentials. The broad goal of this program is to develop and deploy a set of energy-saving technologies, strategies, and techniques, and improve processes for designing, commissioning, and operating commercial buildings, while improving health, comfort, and performance of occupants, all in a manner consistent with sound economic investment practices. Results are to be broadly applicable to the commercial sector for different building sizes and types, e.g. offices and schools, for different classes of ownership, both public and private, and for owner-occupied as well as speculative buildings. The program aims to facilitate significant electricity use savings in the California commercial sector by 2015, while assuring that these savings are affordable and promote high quality indoor environments. The five linked technical program elements contain 14 projects with 41 distinct R&D tasks. Collectively they form a comprehensive Research, Development, and Demonstration (RD&D) program with the potential to capture large savings in the commercial building sector, providing significant economic benefits to

  15. High Performance Home Building Guide for Habitat for Humanity Affiliates

    Energy Technology Data Exchange (ETDEWEB)

    Lindsey Marburger

    2010-10-01

    This guide covers basic principles of high performance Habitat construction, steps to achieving high performance Habitat construction, resources to help improve building practices, materials, etc., and affiliate profiles and recommendations.

  16. High Performance Computing in Science and Engineering '99 : Transactions of the High Performance Computing Center

    CERN Document Server

    Jäger, Willi

    2000-01-01

    The book contains reports about the most significant projects from science and engineering of the Federal High Performance Computing Center Stuttgart (HLRS). They were carefully selected in a peer-review process and are showcases of an innovative combination of state-of-the-art modeling, novel algorithms and the use of leading-edge parallel computer technology. The projects of HLRS are using supercomputer systems operated jointly by university and industry and therefore a special emphasis has been put on the industrial relevance of results and methods.

  17. High Performance Computing in Science and Engineering '98 : Transactions of the High Performance Computing Center

    CERN Document Server

    Jäger, Willi

    1999-01-01

    The book contains reports about the most significant projects from science and industry that are using the supercomputers of the Federal High Performance Computing Center Stuttgart (HLRS). These projects are from different scientific disciplines, with a focus on engineering, physics and chemistry. They were carefully selected in a peer-review process and are showcases for an innovative combination of state-of-the-art physical modeling, novel algorithms and the use of leading-edge parallel computer technology. As HLRS is in close cooperation with industrial companies, special emphasis has been put on the industrial relevance of results and methods.

  18. High Performance Input/Output Systems for High Performance Computing and Four-Dimensional Data Assimilation

    Science.gov (United States)

    Fox, Geoffrey C.; Ou, Chao-Wei

    1997-01-01

    The approach of this task was to apply leading parallel computing research to a number of existing techniques for assimilation, and extract parameters indicating where and how input/output limits computational performance. The following was used for detailed knowledge of the application problems: 1. Developing a parallel input/output system specifically for this application 2. Extracting the important input/output characteristics of data assimilation problems; and 3. Building these characteristics s parameters into our runtime library (Fortran D/High Performance Fortran) for parallel input/output support.

  19. High Performance Computing in Science and Engineering '02 : Transactions of the High Performance Computing Center

    CERN Document Server

    Jäger, Willi

    2003-01-01

    This book presents the state-of-the-art in modeling and simulation on supercomputers. Leading German research groups present their results achieved on high-end systems of the High Performance Computing Center Stuttgart (HLRS) for the year 2002. Reports cover all fields of supercomputing simulation ranging from computational fluid dynamics to computer science. Special emphasis is given to industrially relevant applications. Moreover, by presenting results for both vector sytems and micro-processor based systems the book allows to compare performance levels and usability of a variety of supercomputer architectures. It therefore becomes an indispensable guidebook to assess the impact of the Japanese Earth Simulator project on supercomputing in the years to come.

  20. Monte Carlo simulations for plasma physics

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, M.; Murakami, S.; Nakajima, N.; Wang, W.X. [National Inst. for Fusion Science, Toki, Gifu (Japan)

    2000-07-01

    Plasma behaviours are very complicated and the analyses are generally difficult. However, when the collisional processes play an important role in the plasma behaviour, the Monte Carlo method is often employed as a useful tool. For examples, in neutral particle injection heating (NBI heating), electron or ion cyclotron heating, and alpha heating, Coulomb collisions slow down high energetic particles and pitch angle scatter them. These processes are often studied by the Monte Carlo technique and good agreements can be obtained with the experimental results. Recently, Monte Carlo Method has been developed to study fast particle transports associated with heating and generating the radial electric field. Further it is applied to investigating the neoclassical transport in the plasma with steep gradients of density and temperatures which is beyong the conventional neoclassical theory. In this report, we briefly summarize the researches done by the present authors utilizing the Monte Carlo method. (author)

  1. DOE research in utilization of high-performance computers

    Energy Technology Data Exchange (ETDEWEB)

    Buzbee, B.L.; Worlton, W.J.; Michael, G.; Rodrigue, G.

    1980-12-01

    Department of Energy (DOE) and other Government research laboratories depend on high-performance computer systems to accomplish their programatic goals. As the most powerful computer systems become available, they are acquired by these laboratories so that advances can be made in their disciplines. These advances are often the result of added sophistication to numerical models whose execution is made possible by high-performance computer systems. However, high-performance computer systems have become increasingly complex; consequently, it has become increasingly difficult to realize their potential performance. The result is a need for research on issues related to the utilization of these systems. This report gives a brief description of high-performance computers, and then addresses the use of and future needs for high-performance computers within DOE, the growing complexity of applications within DOE, and areas of high-performance computer systems warranting research. 1 figure.

  2. High Performance Work Practices In Indian Organizations- An Understanding

    OpenAIRE

    Awasthi, Shakti

    2013-01-01

    In todays global competitive era, every business aims to optimize their processes. High performance work practices are such a practice, which can lead to the optimal utilization of human resources. In the present article I have tried to bring into light different aspects related to the high performing work practices in the organizational setup and their implementation can make a difference in the organization. The high performance work practices not only can bring the change in human resource...

  3. High Performance Monopropellants for Future Planetary Ascent Vehicles Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Physical Sciences Inc. proposes to design, develop, and demonstrate, a novel high performance monopropellant for application in future planetary ascent vehicles. Our...

  4. High Performance Computing in Science and Engineering '08 : Transactions of the High Performance Computing Center

    CERN Document Server

    Kröner, Dietmar; Resch, Michael

    2009-01-01

    The discussions and plans on all scienti?c, advisory, and political levels to realize an even larger “European Supercomputer” in Germany, where the hardware costs alone will be hundreds of millions Euro – much more than in the past – are getting closer to realization. As part of the strategy, the three national supercomputing centres HLRS (Stuttgart), NIC/JSC (Julic ¨ h) and LRZ (Munich) have formed the Gauss Centre for Supercomputing (GCS) as a new virtual organization enabled by an agreement between the Federal Ministry of Education and Research (BMBF) and the state ministries for research of Baden-Wurttem ¨ berg, Bayern, and Nordrhein-Westfalen. Already today, the GCS provides the most powerful high-performance computing - frastructure in Europe. Through GCS, HLRS participates in the European project PRACE (Partnership for Advances Computing in Europe) and - tends its reach to all European member countries. These activities aligns well with the activities of HLRS in the European HPC infrastructur...

  5. Approach to the determination of insulin-like-growth-factor-I (IGF-I) concentration in plasma by high-performance liquid chromatography-ion trap mass spectrometry: use of a deconvolution algorithm for the quantification of multiprotonated molecules in electrospray ionization.

    Science.gov (United States)

    Bobin, S; Popot, M A; Bonnaire, Y; Tabet, J C

    2001-11-01

    The insulin-like-growth-factor-I (IGF-I) peptide is known to be a marker for growth hormone administration. The development of a quantification method by electrospray ionization mass spectrometry (ESI-MS) coupled with high-performance liquid chromatography (HPLC) is required. This paper describes a method to quantify IGF-I using the internal standard R3 IGF-I in its oxidized forms. A deconvolution software was used to quantify the set of multi-charged molecules recorded on an ESI ion trap mass spectrometer. The results (i.e., linearity, reproducibility and concentration range) were obtained on standard samples and the described LC-ESI-MS method should be applicable to biological samples.

  6. Magnetic properties of Aurivillius lanthanide-bismuth (LnFeO3nBi4Ti3O12 (n = 1,2 layered titanates

    Directory of Open Access Journals (Sweden)

    Tartaj, J.

    2008-06-01

    Full Text Available Bismuth titanates of Aurivillius layer-structure (BiFeO3nBi4Ti3O12, are of great technological interest because of their applications as non-volatile ferroelectric memories and high-temperature piezoelectric materials. The synthesis and crystallographic characterization of a new family of compounds (LnFeO3nBi4Ti3O12 was recently reported, in which the layers consist of LnFeO3 perovskites with a lanthanide Ln3+ substituting diamagnetic Bi3+. We report herein the magnetic properties of bulk samples, with Ln = Nd, Eu, Gd and Tb, and n = 1 and 2. Single-layer materials are paramagnetic, similar to non-substituted bismuth titanate Bi5FeTi3O15, and show crystal field effects due to the crystallographic environment of Eu3+ and Tb3+. Several anomalies are detected in the magnetization M(T of double-layer (LnFeO32Bi4Ti3O12 compounds, related to the strong magnetism of Tb and Gd, since they weakly appear for Nd and they are absent in the VanVleck Eu3+ ion and in the parent Bi6Fe2Ti3O18 compound.Los titanatos de hierro y bismuto con estructura laminar tipo Aurivillius, (BiFeO3nBi4Ti3O12, tienen un gran interés tecnológico debido a sus aplicaciones como memorias ferroeléctricas no volátiles y como piezoeléctrico cerámico de alta temperatura. La síntesis y la caracterización cristalina de una nueva familia de compuestos (LnFeO3nBi4Ti3O12 han sido recientemente reportadas, en la que el catión diamagnético Bi3+ ha sido sustituido por los paramagnéticos Ln3+ en los bloques de perovskita. Se estudian las propiedades magnéticas de muestras cerámicas en volumen con Ln = Nd, Eu, Gd y Tb, y n = 1 y 2. Los materiales con n=1 son paramagnéticos y similares al no sustituido Bi5FeTi3O15, y muestran efectos de campo cristalino debido al entorno cristalino de Eu3+ y Tb3+. Se han detectado algunas anomalías en la magnetización M(T de los compuestos n=2 (LnFeO32Bi4Ti3O12 que están relacionadas con el fuerte magnetismo de Tb y Gd, que aparecen d

  7. Mechanical Properties of High Performance Cementitious Grout Masterflow 9300

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.

    The present report describes tests carried out on the high performance grout MASTERFLOW 9300, developed by BASF Construction Chemicals A/S.......The present report describes tests carried out on the high performance grout MASTERFLOW 9300, developed by BASF Construction Chemicals A/S....

  8. Myth Busting: Do High-Performance Students Prefer Working Alone?

    Science.gov (United States)

    Walker, Cheryl L.; Shore, Bruce M.

    2015-01-01

    There has been a longstanding assumption that gifted, high-ability, or high-performing students prefer working alone; however, this may not be true in every case. The current study expanded on this assumption to reveal more nuanced learning preferences of these students. Sixty-nine high-performing and community-school students in Grades 5 and 6…

  9. 7 CFR 275.24 - High performance bonuses.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 4 2010-01-01 2010-01-01 false High performance bonuses. 275.24 Section 275.24... High performance bonuses. (a) General rule. (1) FNS will award bonuses totaling $48 million for each fiscal year to State agencies that show high or improved performance in accordance with the performance...

  10. New Entrepreneurs and High Performance Enterprises in the Middle ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    New Entrepreneurs and High Performance Enterprises in the Middle East and North Africa. Book cover New Entrepreneurs and High Performance Enterprises in the Middle East and North Africa. Auteur(s) : OECD, IDRC. Maison(s) d'édition : OECD, IDRC. 6 février 2013. ISBN : 9789264100251. 114 pages. e-ISBN :.

  11. Turning High-Poverty Schools into High-Performing Schools

    Science.gov (United States)

    Parrett, William H.; Budge, Kathleen

    2012-01-01

    If some schools can overcome the powerful and pervasive effects of poverty to become high performing, shouldn't any school be able to do the same? Shouldn't we be compelled to learn from those schools? Although schools alone will never systemically eliminate poverty, high-poverty, high-performing (HP/HP) schools take control of what they can to…

  12. Mechanical Properties of High Performance Cementitious Grout (II)

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.

    The present report is an update of the report “Mechanical Properties of High Performance Cementitious Grout (I)” [1] and describes tests carried out on the high performance grout MASTERFLOW 9500, marked “WMG 7145 FP”, developed by BASF Construction Chemicals A/S and designed for use in grouted co...... connections of offshore windmill foundations....

  13. From the Editor: The High Performance Computing Act of 1991.

    Science.gov (United States)

    McClure, Charles R.

    1992-01-01

    Discusses issues related to the High Performance Computing and Communication program and National Research and Education Network (NREN) established by the High Performance Computing Act of 1991, including program management, specific program development, affecting policy decisions, access to the NREN, the Department of Education role, and…

  14. Interaction of Fast Ions with Global Plasma Modes in the C-2 Field Reversed Configuration Experiment

    Science.gov (United States)

    Smirnov, Artem; Dettrick, Sean; Clary, Ryan; Korepanov, Sergey; Thompson, Matthew; Trask, Erik; Tuszewski, Michel

    2012-10-01

    A high-confinement operating regime [1] with plasma lifetimes significantly exceeding past empirical scaling laws was recently obtained by combining plasma gun edge biasing and tangential Neutral Beam Injection (NBI) in the C-2 field-reversed configuration (FRC) experiment [2, 3]. We present experimental and computational results on the interaction of fast ions with the n=2 rotational and n=1 wobble modes in the C-2 FRC. It is found that the n=2 mode is similar to quadrupole magnetic fields in its detrimental effect on the fast ion transport due to symmetry breaking. The plasma gun generates an inward radial electric field, thus stabilizing the n=2 rotational instability without applying the quadrupole magnetic fields. The resultant FRCs are nearly axisymmetric, which enables fast ion confinement. The NBI further suppresses the n=2 mode, improves the plasma confinement characteristics, and increases the plasma configuration lifetime [4]. The n=1 wobble mode has relatively little effect on the fast ion transport, likely due to the approximate axisymmetry about the displaced plasma column. [4pt] [1] M. Tuszewski et al., Phys. Rev. Lett. 108, 255008 (2012).[0pt] [2] M. Binderbauer et al., Phys. Rev. Lett. 105, 045003 (2010).[0pt] [3] H.Y. Guo et al., Phys. Plasmas 18, 056110 (2011).[0pt] [4] M. Tuszewski et al., Phys. Plasmas 19, 056108 (2012)

  15. A new high performance field reversed configuration operating regime in the C-2 device

    Energy Technology Data Exchange (ETDEWEB)

    Tuszewski, M.; Smirnov, A.; Thompson, M. C.; Barnes, D.; Binderbauer, M. W.; Brown, R.; Bui, D. Q.; Clary, R.; Conroy, K. D.; Deng, B. H.; Dettrick, S. A.; Douglass, J. D.; Garate, E.; Glass, F. J.; Gota, H.; Guo, H.Y.; Gupta, D.; Gupta, S.; Kinley, J. S.; Knapp, K. [Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688 (United States); and others

    2012-05-15

    Large field reversed configurations (FRCs) are produced in the C-2 device by combining dynamic formation and merging processes. The good confinement of these FRCs must be further improved to achieve sustainment with neutral beam (NB) injection and pellet fuelling. A plasma gun is installed at one end of the C-2 device to attempt electric field control of the FRC edge layer. The gun inward radial electric field counters the usual FRC spin-up and mitigates the n = 2 rotational instability without applying quadrupole magnetic fields. Better plasma centering is also obtained, presumably from line-tying to the gun electrodes. The combined effects of the plasma gun and of neutral beam injection lead to the high performance FRC operating regime, with FRC lifetimes up to 3 ms and with FRC confinement times improved by factors 2 to 4.

  16. Diazepam e nordiazepam em plasma: métodos de extração líquido-líquido e em fase sólida no pré-tratamento de amostras para análise cromatográfica em fase líquida Diazepam and nordiazepam in plasma: liquid-liquid and solid phase extraction in sample pre-treatment for high performance liquid chromatography analysis

    Directory of Open Access Journals (Sweden)

    Ellen Figueiredo Freire

    2005-10-01

    Full Text Available Analysis of diazepam (DZP and its active metabolite nordiazepam (NDZP in plasma is commonly performed in clinical medicine to ensure proper therapeutic effects while minimizing the incidence of toxicity. This study aimed to optimize analytical parameters and compare two pre-treatment techniques, liquid-liquid (LLE and solid phase extraction (SPE, as well as liquid chromatographic conditions to analyze simultaneously DZP and NDZP in plasma from 20 patients treated with a daily dose of 10 mg. Both techniques showed to be well in line with the international criteria for analytical validation, which permitted to quantify DZP (66.2 - 1148.6 ng mL-1 and NDZP (138.5 - 808.6 ng mL -1 in all samples. The correlation coefficients between SPE and LLE were respectively 0.9729 for DZP and 0.9643 for NDZP.

  17. Propranolol plasma monitoring in children submitted to surgery of tetralogy of Fallot by a micromethod using high performance liquid chromatography Monitoramento do propranolol plasmático em crianças operadas da tetralogia de Fallot através de micrométodo utilizando a cromatografia líquida de alta eficiência

    Directory of Open Access Journals (Sweden)

    Cristina Sanches

    2007-01-01

    Full Text Available OBJECTIVE: To evaluate the analytical micromethod using liquid chromatography for the quantification of propranolol in children submitted to surgery of tetralogy of Fallot (TLF. Methods: Only 0.2 mL of plasma is required for the assay. Peaks eluted at 8.4 (Propranolol and 17.5 min (verapamil, internal standard from a C18 column, with a mobile phase 0.1 M acetate buffer, pH 5.0, and acetonitrile (60:40, v/v at flow rate 0.7 mL/min, detected at 290 nm (excitation and 358 nm (emission. Surgery was started 776 min of drug administration (8.7mg, mean; seven blood samples were collected from six patients (4M/2F; 2.1yrs;11.5kg; 0.80m; 18.9kg/m². RESULTS: Confidence limits of the method showed high selectivity and recovery, sensitivity of 0.02ng/mL, good linearity (0.05-1000ng/mL, precision of 8.6% and accuracy of 3.1%. The mean duration of surgery was 283.2min, with the patients remaining under cardiopulmonary bypass (CPB for 114min. A declining curve of propranolol plasma concentration was obtained after the last dose in the night that preceded the day of surgery. Plasma concentration also was normalized with hematocrit due to the hemodilution caused by the CPB procedure. On the other hand a decrease on drug plasma concentration was obtained between periods, the beginning of surgery to the postoperative day 2 (7.09 ng/mL and 0.05 ng/mL, pOBJETIVO: Avaliar o micrométodo analítico empregando a cromatografia líquida para quantificação de propranolol em crianças operadas de tetralogia de Fallot (TLF. MÉTODO: Requereu-se apenas volumes de 0,2mL de plasma para a realização do ensaio. Os picos foram eluídos em 8.4 (Propranolol e 17.5 min (verapamil, padrão interno de uma coluna C18, com fase móvel (tampão acetato 0,1 M pH 5,0 e acetonitrila, 60:40, v/v em fluxo de 0,7 mL/min, sendo detectados em 290 nm (excitação e em 358 nm (emissão. A cirurgia iniciou-se 776 min depois da dose administrada (8,7mg, média e sete amostras de sangue foram

  18. A Versatile Glass Processor for High-Performance Photonic Platforms

    Science.gov (United States)

    2015-12-08

    SECURITY CLASSIFICATION OF: With the DURIP fund, we acquire a glass processing station to enhance our capabilities to achieve ultra-high performance...funded by PECASE (supported by DoD-ARO under the contract/grant number W911NF-12-1-0026) on high performance optical sensors. The multipurpose glass ...Distribution Unlimited UU UU UU UU 08-12-2016 1-Aug-2014 31-Jul-2015 Final Report: A Versatile Glass Processor for High-Performance Photonic Platforms The views

  19. Inclusive vision for high performance computing at the CSIR

    CSIR Research Space (South Africa)

    Gazendam, A

    2006-02-01

    Full Text Available gaining popularity in South Africa. One reason for this relatively slow adoption is the lack of appropriate scientific computing infrastructure. Open and distributed high-performance computing (HPC) represents a radically new computing concept for data...

  20. Fracture in high performance fibre reinforced concrete pavement materials

    CSIR Research Space (South Africa)

    Denneman, E

    2011-05-01

    Full Text Available high performance fibre reinforced concrete pavement slab with a nominal thickness of approximately 50 mm. The material has a significant post crack stress capacity compared to plain concrete. Current design methods for UTCRCP are based on conventional...

  1. Application of ultra-high performance concrete to bridge girders.

    Science.gov (United States)

    2009-02-01

    "Ultra-High Performance Concrete (UHPC) is a new class of concrete that has superior performance characteristics : compared to conventional concrete. The enhanced strength and durability properties of UHPC are mainly due to optimized : particle grada...

  2. High Performance Concrete (HPC) bridge project for SR 43.

    Science.gov (United States)

    2012-10-01

    The objective of this research was to develop and test high performance concrete mixtures, made of locally available materials, having : durability characteristics that far exceed those of conventional concrete mixtures. Based on the results from the...

  3. Internal curing of high-performance concrete for bridge decks.

    Science.gov (United States)

    2013-03-01

    High performance concrete (HPC) provides a long lasting, durable concrete that is typically used in bridge decks due to its low permeability, high abrasion resistance, freeze-thaw resistance and strength. However, this type of concrete is highly susc...

  4. Innovative Deep Throttling, High Performance Injector Concept Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Science and Technology Applications, LLC's (STA) vision for a versatile space propulsion system is a highly throttleable, high performance, and cost effective Liquid...

  5. Energy Design Guidelines for High Performance Schools: Tropical Island Climates

    Energy Technology Data Exchange (ETDEWEB)

    None

    2004-11-01

    Design guidelines outline high performance principles for the new or retrofit design of K-12 schools in tropical island climates. By incorporating energy improvements into construction or renovation plans, schools can reduce energy consumption and costs.

  6. High-performance inhoudsstoffen vinden hun weg naar de markt

    NARCIS (Netherlands)

    Meer, van der I.M.; Vollebregt, M.

    2015-01-01

    High-performance inhoudsstoffen uit biomassa ontstijgen de onderzoekslaboratoria en duiken op in proefprojecten met bedrijven en concrete toepassingen in eindproducten. Het tempo waarmee dit gebeurt en de onderliggende markt drivers verschillen per productgebied, zo blijkt uit een rondje langs

  7. High Performance Low Mass Nanowire Enabled Heatpipe Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Heat pipes are widely used for passive, two-phase electronics cooling. As advanced high power, high performance electronics in space based and terrestrial...

  8. Advanced Risk Analysis for High-Performing Organizations

    National Research Council Canada - National Science Library

    Alberts, Christopher; Dorofee, Audrey

    2006-01-01

    ...) are not readily identified using traditional risk analysis techniques. High-performing organizations have the basic skills needed to identify and manage these new types of risk, but lack sufficient techniques...

  9. Mastering the Challenge of High-Performance Computing.

    Science.gov (United States)

    Roach, Ronald

    2003-01-01

    Discusses how, just as all of higher education got serious with wiring individual campuses for the Internet, the nation's leading research institutions have initiated "high-performance computing." Describes several such initiatives involving historically black colleges and universities. (EV)

  10. Analysis of Simvastatin using a Simple and Fast High Performance ...

    African Journals Online (AJOL)

    phase high performance liquid chromatography (RP-HPLC) analytical method for the lipid lowering drug, simvastatin, and to apply the developed method to study the solubility of the drug in various oils and surfactants. Methods: Isocratic ...

  11. High Performance Low Mass Nanowire Enabled Heatpipe Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Illuminex Corporation proposes a NASA Phase I SBIR project to develop high performance, lightweight, low-profile heat pipes with enhanced thermal transfer properties...

  12. Export Control of High Performance Computing: Analysis and Alternative Strategies

    National Research Council Canada - National Science Library

    Holland, Charles

    2001-01-01

    High performance computing has historically played an important role in the ability of the United States to develop and deploy a wide range of national security capabilities, such as stealth aircraft...

  13. Validation of Kinetic-Turbulent-Neoclassical Theory for Edge Intrinsic Rotation in DIII-D Plasmas

    Science.gov (United States)

    Ashourvan, Arash

    2017-10-01

    Recent experiments on DIII-D with low-torque neutral beam injection (NBI) have provided a validation of a new model of momentum generation in a wide range of conditions spanning L- and H-mode with direct ion and electron heating. A challenge in predicting the bulk rotation profile for ITER has been to capture the physics of momentum transport near the separatrix and steep gradient region. A recent theory has presented a model for edge momentum transport which predicts the value and direction of the main-ion intrinsic velocity at the pedestal-top, generated by the passing orbits in the inhomogeneous turbulent field. In this study, this model-predicted velocity is tested on DIII-D for a database of 44 low-torque NBI discharges comprised of bothL- and H-mode plasmas. For moderate NBI powers (PNBInet injected torque through the edge can exceed 1 N.m in the counter-current direction. The theory model has been extended to compute the rotation degradation from this counter-current NBI torque by solving a reduced momentum evolution equation for the edge and found the revised velocity prediction to be in agreement with experiment. Projecting to the ITER baseline scenario, this model predicts a value for the pedestal-top rotation (ρ 0.9) comparable to 4 kRad/s. Using the theory modeled - and now tested - velocity to predict the bulk plasma rotation opens up a path to more confidently projecting the confinement and stability in ITER. Supported by the US DOE under DE-AC02-09CH11466 and DE-FC02-04ER54698.

  14. Architecture and Programming Models for High Performance Intensive Computation

    Science.gov (United States)

    2016-06-29

    AFRL-AFOSR-VA-TR-2016-0230 Architecture and Programming Models for High Performance Intensive Computation XiaoMing Li UNIVERSITY OF DELAWARE Final...TITLE AND SUBTITLE Architecture and Programming Models for High Performance Intensive Computation 5a. CONTRACT NUMBER 5b. GRANT NUMBER FA9550-13-1-0213...developing an efficient system architecture and software tools for building and running Dynamic Data Driven Application Systems (DDDAS). The foremost

  15. Energy Design Guidelines for High Performance Schools: Tropical Island Climates

    Energy Technology Data Exchange (ETDEWEB)

    2004-11-01

    The Energy Design Guidelines for High Performance Schools--Tropical Island Climates provides school boards, administrators, and design staff with guidance to help them make informed decisions about energy and environmental issues important to school systems and communities. These design guidelines outline high performance principles for the new or retrofit design of your K-12 school in tropical island climates. By incorporating energy improvements into their construction or renovation plans, schools can significantly reduce energy consumption and costs.

  16. Highlighting High Performance: Whitman Hanson Regional High School; Whitman, Massachusetts

    Energy Technology Data Exchange (ETDEWEB)

    2006-06-01

    This brochure describes the key high-performance building features of the Whitman-Hanson Regional High School. The brochure was paid for by the Massachusetts Technology Collaborative as part of their Green Schools Initiative. High-performance features described are daylighting and energy-efficient lighting, indoor air quality, solar and wind energy, building envelope, heating and cooling systems, water conservation, and acoustics. Energy cost savings are also discussed.

  17. Mechanical Properties of High Performance Cementitious Grout Masterflow 9200

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.

    The present report describes tests carried out on the high performance grout Masterflow 9200, developed by BASF Construction Chemicals A/S and designed for use in grouted connections of windmill foundations.......The present report describes tests carried out on the high performance grout Masterflow 9200, developed by BASF Construction Chemicals A/S and designed for use in grouted connections of windmill foundations....

  18. Defining a Comprehensive Threat Model for High Performance Computational Clusters

    OpenAIRE

    Mogilevsky, Dmitry; Lee, Adam; Yurcik, William

    2005-01-01

    Over the past decade, high performance computational (HPC) clusters have become mainstream in academic and industrial settings as accessible means of computation. Throughout their proliferation, HPC security has been a secondary concern to performance. It is evident, however, that ensuring HPC security presents different challenges than the ones faced when dealing with traditional networks. To design suitable security measures for high performance computing, it is necessary to first realize t...

  19. High performance top-gated multilayer WSe2 field effect transistors

    Science.gov (United States)

    Pudasaini, Pushpa Raj; Stanford, Michael G.; Oyedele, Akinola; Wong, Anthony T.; Hoffman, Anna N.; Briggs, Dayrl P.; Xiao, Kai; Mandrus, David G.; Ward, Thomas Z.; Rack, Philip D.

    2017-11-01

    In this paper, high performance top-gated WSe2 field effect transistor (FET) devices are demonstrated via a two-step remote plasma assisted ALD process. High-quality, low-leakage aluminum oxide (Al2O3) gate dielectric layers are deposited onto the WSe2 channel using a remote plasma assisted ALD process with an ultrathin (∼1 nm) titanium buffer layer. The first few nanometers (∼2 nm) of the Al2O3 dielectric film is deposited at relatively low temperature (i.e. 50 °C) and remainder of the film is deposited at 150 °C to ensure the conformal coating of Al2O3 on the WSe2 surface. Additionally, an ultra-thin titanium buffer layer is introduced at the WSe2 channel surface prior to ALD process to mitigate oxygen plasma induced doping effects. Excellent device characteristics with current on–off ratio in excess of 106 and a field effect mobility as high as 70.1 cm2 V–1 s–1 are achieved in a few-layer WSe2 FET device with a 30 nm Al2O3 top-gate dielectric. With further investigation and careful optimization, this method can play an important role for the realization of high performance top gated FETs for future optoelectronic device applications.

  20. A review of recent developments in joining high-performance thermoplastic composites

    Science.gov (United States)

    Cole, K. C.

    1991-06-01

    There is currently a great deal of interest in the use of thermoplastic polymers as matrices in fiber reinforced composites for high performance applications, such as those encountered in the aerospace industry. These materials include polyether ether ketone (PEEK), polyphenylene sulphide (PPS), polyetherimide (PEI), polyamideimide (PAI), polyamides, polyimides, and polysulphones. A literature review is provided on the different ways of joining high performance thermoplastic composites by adhesive and fusion bonding. The discussion on adhesive bonding includes examination of the performance of specific adhesive/thermoplastic combinations and of techniques for the preparation of composite surfaces: abrasion, etching, flame, and plasma treatments. Thermoplastic composite welding techniques discussed in depth include the following: heated press welding, resistance welding, induction welding, and ultrasonic welding. Works which examine or compare applications for these bonding techniques are also reviewed.

  1. Observation of SOL Current Correlated with MHD Activity in NBI-heated DIII-D Tokamak Discharges

    Energy Technology Data Exchange (ETDEWEB)

    H. Takahashi; E.D. Fredrickson; M.J. Schaffer; M.E. Austin; T.E. Evans; L.L. Lao; J.G. Watkins

    2004-03-26

    This work investigates the potential roles played by the scrape-off-layer current (SOLC) in MHD activity of tokamak plasmas, including effects on stability. SOLCs are found during MHD activity that are: (1) slowly growing after a mode-locking-like event, (2) oscillating in the several kHz range and phase-locked with magnetic and electron temperature oscillations, (3) rapidly growing with a sub-ms time scale during a thermal collapse and a current quench, and (4) spiky in temporal behavior and correlated with spiky features in Da signals commonly identified with the edge localized mode (ELM). These SOLCs are found to be an integral part of the MHD activity, with a propensity to flow in a toroidally non-axisymmetric pattern and with magnitude potentially large enough to play a role in the MHD stability. Candidate mechanisms that can drive these SOLCs are identified: (a) toroidally non-axisymmetric thermoelectric potential, (b) electromotive force (EMF) from MHD activity, and (c) flux swing, both toroidal and poloidal, of the plasma column. An effect is found, stemming from the shear in the field line pitch angle, that mitigates the efficacy of a toroidally non-axisymmetric SOLC to generate a toroidally non-axisymmetric error field. Other potential magnetic consequences of the SOLC are identified: (i) its error field can introduce complications in feedback control schemes for stabilizing MHD activity and (ii) its toroidally non-axisymmetric field can be falsely identified as an axisymmetric field by the tokamak control logic and in equilibrium reconstruction. The radial profile of a SOLC observed during a quiescent discharge period is determined, and found to possess polarity reversals as a function of radial distance.

  2. Producing High-Performance, Stable, Sheared-Flow Z-Pinches in the FuZE project

    Science.gov (United States)

    Golingo, R. P.; Shumlak, U.,; Nelson, B. A.; Claveau, E. L.; Forbes, E. G.; Stepanov, A. D.; Weber, T. R.; Zhang, Y.; McLean, H. S.; Tummel, K. K.; Higginson, D. P.; Schmidt, A. E.; University of Washington (UW) Collaboration; Lawrence Livermore National Laboratory (LLNL) Collaboration

    2017-10-01

    The Fusion Z-Pinch Experiment (FuZE) has made significant strides towards generating high-performance, stable Z-pinch plasmas with goals of ne = 1018 cm-3 and T =1 keV. The Z-pinch plasmas are stabilized with a sheared axial flow that is driven by a coaxial accelerator. The new FuZE device has been constructed and reproduces the major scientific achievements the ZaP project at the University of Washington; ne = 1016 cm-3,T = 100 eV, r20 μs. These parameters are measured with an array of magnetic field probes, spectroscopy, and fast framing cameras. The plasma parameters are achieved using a small fraction of the maximum energy storage and gas injection capability of the FuZE device. Higher density, ne = 5×1017 cm-3, and temperature, T = 500 eV, Z-pinch plasmas are formed by increasing the pinch current. At the higher voltages and currents, the ionization rates in the accelerator increase. By modifying the neutral gas profile in the accelerator, the plasma flow from the accelerator is maintained, driving the flow shear. Formation and sustainment of the sheared-flow Z-pinch plasma will be discussed. Experimental data demonstrating high performance plasmas in a stable Z-pinches will be shown. This work is supported by an award from US ARPA-E.

  3. Resource estimation in high performance medical image computing.

    Science.gov (United States)

    Banalagay, Rueben; Covington, Kelsie Jade; Wilkes, D M; Landman, Bennett A

    2014-10-01

    Medical imaging analysis processes often involve the concatenation of many steps (e.g., multi-stage scripts) to integrate and realize advancements from image acquisition, image processing, and computational analysis. With the dramatic increase in data size for medical imaging studies (e.g., improved resolution, higher throughput acquisition, shared databases), interesting study designs are becoming intractable or impractical on individual workstations and servers. Modern pipeline environments provide control structures to distribute computational load in high performance computing (HPC) environments. However, high performance computing environments are often shared resources, and scheduling computation across these resources necessitates higher level modeling of resource utilization. Submission of 'jobs' requires an estimate of the CPU runtime and memory usage. The resource requirements for medical image processing algorithms are difficult to predict since the requirements can vary greatly between different machines, different execution instances, and different data inputs. Poor resource estimates can lead to wasted resources in high performance environments due to incomplete executions and extended queue wait times. Hence, resource estimation is becoming a major hurdle for medical image processing algorithms to efficiently leverage high performance computing environments. Herein, we present our implementation of a resource estimation system to overcome these difficulties and ultimately provide users with the ability to more efficiently utilize high performance computing resources.

  4. Resource Estimation in High Performance Medical Image Computing

    Science.gov (United States)

    Banalagay, Rueben; Covington, Kelsie Jade; Wilkes, D.M.

    2015-01-01

    Medical imaging analysis processes often involve the concatenation of many steps (e.g., multi-stage scripts) to integrate and realize advancements from image acquisition, image processing, and computational analysis. With the dramatic increase in data size for medical imaging studies (e.g., improved resolution, higher throughput acquisition, shared databases), interesting study designs are becoming intractable or impractical on individual workstations and servers. Modern pipeline environments provide control structures to distribute computational load in high performance computing (HPC) environments. However, high performance computing environments are often shared resources, and scheduling computation across these resources necessitates higher level modeling of resource utilization. Submission of ‘jobs’ requires an estimate of the CPU runtime and memory usage. The resource requirements for medical image processing algorithms are difficult to predict since the requirements can vary greatly between different machines, different execution instances, and different data inputs. Poor resource estimates can lead to wasted resources in high performance environments due to incomplete executions and extended queue wait times. Hence, resource estimation is becoming a major hurdle for medical image processing algorithms to efficiently leverage high performance computing environments. Herein, we present our implementation of a resource estimation system to overcome these difficulties and ultimately provide users with the ability to more efficiently utilize high performance computing resources. PMID:24906466

  5. High performance leadership in unusually challenging educational circumstances

    Directory of Open Access Journals (Sweden)

    Andy Hargreaves

    2015-04-01

    Full Text Available This paper draws on findings from the results of a study of leadership in high performing organizations in three sectors. Organizations were sampled and included on the basis of high performance in relation to no performance, past performance, performance among similar peers and performance in the face of limited resources or challenging circumstances. The paper concentrates on leadership in four schools that met the sample criteria.  It draws connections to explanations of the high performance ofEstoniaon the OECD PISA tests of educational achievement. The article argues that leadership in these four schools that performed above expectations comprised more than a set of competencies. Instead, leadership took the form of a narrative or quest that pursued an inspiring dream with relentless determination; took improvement pathways that were more innovative than comparable peers; built collaboration and community including with competing schools; and connected short-term success to long-term sustainability.

  6. A Component Architecture for High-Performance Scientific Computing

    Energy Technology Data Exchange (ETDEWEB)

    Bernholdt, David E; Allan, Benjamin A; Armstrong, Robert C; Bertrand, Felipe; Chiu, Kenneth; Dahlgren, Tamara L; Damevski, Kostadin; Elwasif, Wael R; Epperly, Thomas G; Govindaraju, Madhusudhan; Katz, Daniel S; Kohl, James A; Krishnan, Manoj Kumar; Kumfert, Gary K; Larson, J Walter; Lefantzi, Sophia; Lewis, Michael J; Malony, Allen D; McInnes, Lois C; Nieplocha, Jarek; Norris, Boyana; Parker, Steven G; Ray, Jaideep; Shende, Sameer; Windus, Theresa L; Zhou, Shujia

    2006-07-03

    The Common Component Architecture (CCA) provides a means for software developers to manage the complexity of large-scale scientific simulations and to move toward a plug-and-play environment for high-performance computing. In the scientific computing context, component models also promote collaboration using independently developed software, thereby allowing particular individuals or groups to focus on the aspects of greatest interest to them. The CCA supports parallel and distributed computing as well as local high-performance connections between components in a language-independent manner. The design places minimal requirements on components and thus facilitates the integration of existing code into the CCA environment. The CCA model imposes minimal overhead to minimize the impact on application performance. The focus on high performance distinguishes the CCA from most other component models. The CCA is being applied within an increasing range of disciplines, including combustion research, global climate simulation, and computational chemistry.

  7. A Component Architecture for High-Performance Scientific Computing

    Energy Technology Data Exchange (ETDEWEB)

    Bernholdt, D E; Allan, B A; Armstrong, R; Bertrand, F; Chiu, K; Dahlgren, T L; Damevski, K; Elwasif, W R; Epperly, T W; Govindaraju, M; Katz, D S; Kohl, J A; Krishnan, M; Kumfert, G; Larson, J W; Lefantzi, S; Lewis, M J; Malony, A D; McInnes, L C; Nieplocha, J; Norris, B; Parker, S G; Ray, J; Shende, S; Windus, T L; Zhou, S

    2004-12-14

    The Common Component Architecture (CCA) provides a means for software developers to manage the complexity of large-scale scientific simulations and to move toward a plug-and-play environment for high-performance computing. In the scientific computing context, component models also promote collaboration using independently developed software, thereby allowing particular individuals or groups to focus on the aspects of greatest interest to them. The CCA supports parallel and distributed computing as well as local high-performance connections between components in a language-independent manner. The design places minimal requirements on components and thus facilitates the integration of existing code into the CCA environment. The CCA model imposes minimal overhead to minimize the impact on application performance. The focus on high performance distinguishes the CCA from most other component models. The CCA is being applied within an increasing range of disciplines, including combustion research, global climate simulation, and computational chemistry.

  8. High Performance Fiber Reinforced Cement Composites 6 HPFRCC 6

    CERN Document Server

    Reinhardt, Hans; Naaman, A

    2012-01-01

    High Performance Fiber Reinforced Cement Composites (HPFRCC) represent a class of cement composites whose stress-strain response in tension undergoes strain hardening behaviour accompanied by multiple cracking, leading to a high strain prior to failure. The primary objective of this International Workshop was to provide a compendium of up-to-date information on the most recent developments and research advances in the field of High Performance Fiber Reinforced Cement Composites. Approximately 65 contributions from leading world experts are assembled in these proceedings and provide an authoritative perspective on the subject. Special topics include fresh and hardening state properties; self-compacting mixtures; mechanical behavior under compressive, tensile, and shear loading; structural applications; impact, earthquake and fire resistance; durability issues; ultra-high performance fiber reinforced concrete; and textile reinforced concrete. Target readers: graduate students, researchers, fiber producers, desi...

  9. Designing high-Performance layered thermoelectric materials through orbital engineering

    DEFF Research Database (Denmark)

    Zhang, Jiawei; Song, Lirong; Madsen, Georg K. H.

    2016-01-01

    Thermoelectric technology, which possesses potential application in recycling industrial waste heat as energy, calls for novel high-performance materials. The systematic exploration of novel thermoelectric materials with excellent electronic transport properties is severely hindered by limited...... insight into the underlying bonding orbitals of atomic structures. Here we propose a simple yet successful strategy to discover and design high-performance layered thermoelectric materials through minimizing the crystal field splitting energy of orbitals to realize high orbital degeneracy. The approach......-abundant elements. Moreover, the approach can be extended to several other non-cubic materials, thereby substantially accelerating the screening and design of new thermoelectric materials....

  10. Contemporary high performance computing from petascale toward exascale

    CERN Document Server

    Vetter, Jeffrey S

    2013-01-01

    Contemporary High Performance Computing: From Petascale toward Exascale focuses on the ecosystems surrounding the world's leading centers for high performance computing (HPC). It covers many of the important factors involved in each ecosystem: computer architectures, software, applications, facilities, and sponsors. The first part of the book examines significant trends in HPC systems, including computer architectures, applications, performance, and software. It discusses the growth from terascale to petascale computing and the influence of the TOP500 and Green500 lists. The second part of the

  11. High-Performance Matrix-Vector Multiplication on the GPU

    DEFF Research Database (Denmark)

    Sørensen, Hans Henrik Brandenborg

    2012-01-01

    In this paper, we develop a high-performance GPU kernel for one of the most popular dense linear algebra operations, the matrix-vector multiplication. The target hardware is the most recent Nvidia Tesla 20-series (Fermi architecture), which is designed from the ground up for scientific computing....... We show that it is essentially a matter of fully utilizing the fine-grained parallelism of the many-core GPU in order to achieve high-performance for dense matrix-vector multiplication. We show that auto-tuning can be successfully employed to the GPU kernel so that it performs well for all matrix...

  12. High performance computing and communications: FY 1997 implementation plan

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    The High Performance Computing and Communications (HPCC) Program was formally authorized by passage, with bipartisan support, of the High-Performance Computing Act of 1991, signed on December 9, 1991. The original Program, in which eight Federal agencies participated, has now grown to twelve agencies. This Plan provides a detailed description of the agencies` FY 1996 HPCC accomplishments and FY 1997 HPCC plans. Section 3 of this Plan provides an overview of the HPCC Program. Section 4 contains more detailed definitions of the Program Component Areas, with an emphasis on the overall directions and milestones planned for each PCA. Appendix A provides a detailed look at HPCC Program activities within each agency.

  13. Visualization and Data Analysis for High-Performance Computing

    Energy Technology Data Exchange (ETDEWEB)

    Sewell, Christopher Meyer [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-27

    This is a set of slides from a guest lecture for a class at the University of Texas, El Paso on visualization and data analysis for high-performance computing. The topics covered are the following: trends in high-performance computing; scientific visualization, such as OpenGL, ray tracing and volume rendering, VTK, and ParaView; data science at scale, such as in-situ visualization, image databases, distributed memory parallelism, shared memory parallelism, VTK-m, "big data", and then an analysis example.

  14. Profiling high performance dense linear algebra algorithms on multicore architectures for power and energy efficiency

    KAUST Repository

    Ltaief, Hatem

    2011-08-31

    This paper presents the power profile of two high performance dense linear algebra libraries i.e., LAPACK and PLASMA. The former is based on block algorithms that use the fork-join paradigm to achieve parallel performance. The latter uses fine-grained task parallelism that recasts the computation to operate on submatrices called tiles. In this way tile algorithms are formed. We show results from the power profiling of the most common routines, which permits us to clearly identify the different phases of the computations. This allows us to isolate the bottlenecks in terms of energy efficiency. Our results show that PLASMA surpasses LAPACK not only in terms of performance but also in terms of energy efficiency. © 2011 Springer-Verlag.

  15. A Research and Development Strategy for High Performance Computing.

    Science.gov (United States)

    Office of Science and Technology Policy, Washington, DC.

    This report is the result of a systematic review of the status and directions of high performance computing and its relationship to federal research and development. Conducted by the Federal Coordinating Council for Science, Engineering, and Technology (FCCSET), the review involved a series of workshops attended by numerous computer scientists and…

  16. Contemporary high performance computing from petascale toward exascale

    CERN Document Server

    Vetter, Jeffrey S

    2015-01-01

    A continuation of Contemporary High Performance Computing: From Petascale toward Exascale, this second volume continues the discussion of HPC flagship systems, major application workloads, facilities, and sponsors. The book includes of figures and pictures that capture the state of existing systems: pictures of buildings, systems in production, floorplans, and many block diagrams and charts to illustrate system design and performance.

  17. Enabling High-Performance Computing as a Service

    KAUST Repository

    AbdelBaky, Moustafa

    2012-10-01

    With the right software infrastructure, clouds can provide scientists with as a service access to high-performance computing resources. An award-winning prototype framework transforms the Blue Gene/P system into an elastic cloud to run a representative HPC application. © 2012 IEEE.

  18. Effect of residual elements on high performance nickel base ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 28; Issue 4. Effect of residual elements on high performance nickel base superalloys for gas turbines and strategies for manufacture. O P Sinha M Chatterjee V V R S Sarma S N Jha. Volume 28 Issue 4 July 2005 pp 379-382 ...

  19. Dynamic Social Networks in High Performance Football Coaching

    Science.gov (United States)

    Occhino, Joseph; Mallett, Cliff; Rynne, Steven

    2013-01-01

    Background: Sports coaching is largely a social activity where engagement with athletes and support staff can enhance the experiences for all involved. This paper examines how high performance football coaches develop knowledge through their interactions with others within a social learning theory framework. Purpose: The key purpose of this study…

  20. Two Profiles of the Dutch High Performing Employee

    Science.gov (United States)

    de Waal, A. A.; Oudshoorn, Michella

    2015-01-01

    Purpose: The purpose of this study is to explore the profile of an ideal employee, to be more precise the behavioral characteristics of the Dutch high-performing employee (HPE). Organizational performance depends for a large part on the commitment of employees. Employees provide their knowledge, skills, experiences and creativity to the…

  1. Understanding the Work and Learning of High Performance Coaches

    Science.gov (United States)

    Rynne, Steven B.; Mallett, Cliff J.

    2012-01-01

    Background: The development of high performance sports coaches has been proposed as a major imperative in the professionalization of sports coaching. Accordingly, an increasing body of research is beginning to address the question of how coaches learn. While this is important work, an understanding of how coaches learn must be underpinned by an…

  2. The Case for High-Performance, Healthy Green Schools

    Science.gov (United States)

    Carter, Leesa

    2011-01-01

    When trying to reach their sustainability goals, schools and school districts often run into obstacles, including financing, training, and implementation tools. Last fall, the U.S. Green Building Council-Georgia (USGBC-Georgia) launched its High Performance, Healthy Schools (HPHS) Program to help Georgia schools overcome those obstacles. By…

  3. Neural Correlates of High Performance in Foreign Language Vocabulary Learning

    Science.gov (United States)

    Macedonia, Manuela; Muller, Karsten; Friederici, Angela D.

    2010-01-01

    Learning vocabulary in a foreign language is a laborious task which people perform with varying levels of success. Here, we investigated the neural underpinning of high performance on this task. In a within-subjects paradigm, participants learned 92 vocabulary items under two multimodal conditions: one condition paired novel words with iconic…

  4. Fatigue Behaviour of High Performance Cementitious Grout Masterflow 9500

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.

    The present report describes the fatigue behaviour of the high performance grout MASTERFLOW 9500 subjected to cyclic loading, in air as well as submerged in water, at various frequencies and levels of maximum stress. Part of the results were also reported in [1] together with other mechanical...

  5. Maintaining High-Performance Schools after Construction or Renovation

    Science.gov (United States)

    Luepke, Gary; Ronsivalli, Louis J., Jr.

    2009-01-01

    With taxpayers' considerable investment in schools, it is critical for school districts to preserve their community's assets with new construction or renovation and effective facility maintenance programs. "High-performance" school buildings are designed to link the physical environment to positive student achievement while providing such benefits…

  6. Computer science of the high performance; Informatica del alto rendimiento

    Energy Technology Data Exchange (ETDEWEB)

    Moraleda, A.

    2008-07-01

    The high performance computing is taking shape as a powerful accelerator of the process of innovation, to drastically reduce the waiting times for access to the results and the findings in a growing number of processes and activities as complex and important as medicine, genetics, pharmacology, environment, natural resources management or the simulation of complex processes in a wide variety of industries. (Author)

  7. Development of High Performance Thin Layer Chromatography for ...

    African Journals Online (AJOL)

    and validation, a high performance thin layer chromatography (HPTLC) system with WinCATS software was used. Freshly prepared ... recommended in routine analysis of pharmaceutical products containing lamivudine and tenofovir disoproxil fumarate. Introduction ... A strong system of quality control and quality assurance ...

  8. High Performance Skiing. How to Become a Better Alpine Skier.

    Science.gov (United States)

    Yacenda, John

    This book is intended for people who desire to improve their skiing by exploring high performance techniques leading to: (1) more consistent performance; (2) less fatigue and more endurance; (3) greater strength and flexibility; (4) greater versatility; (5) greater confidence in all skiing conditions; and (6) the knowledge to participate in…

  9. Replica-Based High-Performance Tuple Space Computing

    DEFF Research Database (Denmark)

    Andric, Marina; De Nicola, Rocco; Lluch Lafuente, Alberto

    2015-01-01

    We present the tuple-based coordination language RepliKlaim, which enriches Klaim with primitives for replica-aware coordination. Our overall goal is to offer suitable solutions to the challenging problems of data distribution and locality in large-scale high performance computing. In particular,...

  10. Algorithms and Methods for High-Performance Model Predictive Control

    DEFF Research Database (Denmark)

    Frison, Gianluca

    The goal of this thesis is to investigate algorithms and methods to reduce the solution time of solvers for Model Predictive Control (MPC). The thesis is accompanied with an open-source toolbox for High-Performance implementation of solvers for MPC (HPMPC), that contains the source code of all...

  11. The high performance liquid chromatography (HPLC) analysis of ...

    African Journals Online (AJOL)

    The high performance liquid chromatography (HPLC) analysis of ultraviolet (UV) irradiated chlorophyll a and secondary plant compounds. ... in all the samples leaving a bleached extract suitable for biological assays. Key words: Chlorophyll a, UV radiation, activated charcoal, HPLC, secondary compounds in plant extracts.

  12. Comparative Studies of Some Polypores Using High Performance ...

    African Journals Online (AJOL)

    Isolates of four polypores; Ganoderma colossum, Ganoderma lucidum, Trametes cingulata and Daedalea quercina were compared using the High performance liquid chromatographic profiles of their triterpenoids. A higher abundance of colossolactone E was found in Ganoderma colossum isolate (FC 876) when compared ...

  13. Developments on HNF based high performance and green solid propellants

    NARCIS (Netherlands)

    Keizers, H.L.J.; Heijden, A.E.D.M. van der; Vliet, L.D. van; Welland-Veltmans, W.H.M.; Ciucci, A.

    2001-01-01

    Worldwide developments are ongoing to develop new and more energetic composite solid propellant formulations for space transportation and military applications. Since the 90's, the use of HNF as a new high performance oxidiser is being reinvestigated. Within European development programmes,

  14. High performance sport and sustainability: a contradiction of terms?

    NARCIS (Netherlands)

    Barker, D.; Barker-Ruchtia, N.; Wals, A.E.J.; Tinning, R.

    2014-01-01

    Success in high performance sport has always been highly valued. Today, lucrative contracts, sponsorship deals and opportunities for celebrity status are balanced against substantial time spent training and high chances of failure. With pressure mounting on athletes to make the most of their

  15. Development and validation of a reversed phase High Performance ...

    African Journals Online (AJOL)

    A simple, rapid, accurate and economical isocratic Reversed Phase High Performance Liquid Chromatography (RPHPLC) method was developed, validated and used for the evaluation of content of different brands of paracetamol tablets. The method was validated according to ICH guidelines and may be adopted for the ...

  16. Quantification of Tea Flavonoids by High Performance Liquid Chromatography

    Science.gov (United States)

    Freeman, Jessica D.; Niemeyer, Emily D.

    2008-01-01

    We have developed a laboratory experiment that uses high performance liquid chromatography (HPLC) to quantify flavonoid levels in a variety of commercial teas. Specifically, this experiment analyzes a group of flavonoids known as catechins, plant-derived polyphenolic compounds commonly found in many foods and beverages, including green and black…

  17. An optimized gossypol high-performance liquid chromatography ...

    Indian Academy of Sciences (India)

    A comparative study on gossypol content of various genetic types of pigment glands of cotton varieties was conducted through an optimized high-performance liquid chromatography (HPLC) on a C18 column (4.6 mm × 250 mm, 5 m particle) with methanol–0.5% acetic acid aqueous solution, 90 : 10 (v/v), as mobile phase, ...

  18. Achieving High Performance with FPGA-Based Computing

    Science.gov (United States)

    Herbordt, Martin C.; VanCourt, Tom; Gu, Yongfeng; Sukhwani, Bharat; Conti, Al; Model, Josh; DiSabello, Doug

    2011-01-01

    Numerous application areas, including bioinformatics and computational biology, demand increasing amounts of processing capability. In many cases, the computation cores and data types are suited to field-programmable gate arrays. The challenge is identifying the design techniques that can extract high performance potential from the FPGA fabric. PMID:21603088

  19. Control switching in high performance and fault tolerant control

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2010-01-01

    The problem of reliability in high performance control and in fault tolerant control is considered in this paper. A feedback controller architecture for high performance and fault tolerance is considered. The architecture is based on the Youla-Jabr-Bongiorno-Kucera (YJBK) parameterization. By usi....... The architecture will also allow changing the applied sensors and/or actuators when switching between different controllers. This switchingget particular simple for open-loop stable systems.......The problem of reliability in high performance control and in fault tolerant control is considered in this paper. A feedback controller architecture for high performance and fault tolerance is considered. The architecture is based on the Youla-Jabr-Bongiorno-Kucera (YJBK) parameterization. By using...... the nominal controller in the architecture as a simple and robust controller, it is possible to use the YJBK transfer function for optimization of the closed-loop performance. This can be done both in connections with normal operation of the system as well as in connection with faults in the system...

  20. Design and Modeling of High Performance Permanent Magnet Synchronous Machines

    NARCIS (Netherlands)

    Van der Geest, M.

    2015-01-01

    The electrification of transportation, and especially aerospace transportation, increases the demand for high performance electrical machines. Those machines often need to be fault-tolerant, cheap, highly efficient, light and small, and interface well with the inverter. In addition, the development

  1. A high-performance, low-cost, leading edge discriminator

    Indian Academy of Sciences (India)

    A high-performance, low-cost, leading edge discriminator has been designed with a timing performance comparable to state-of-the-art, commercially available ... Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005, India; Graduate School of Science, Osaka City University, Osaka 558-8585, Japan ...

  2. Buffer-Free High Performance Liquid Chromatography Method for ...

    African Journals Online (AJOL)

    Purpose: To develop and validate a simple, economical and reproducible high performance liquid chromatographic (HPLC) method for the determination of theophylline in pharmaceutical dosage forms. Method: Caffeine was used as the internal standard and reversed phase C-18 column was used to elute the drug and ...

  3. High performance current controller for particle accelerator magnets supply

    DEFF Research Database (Denmark)

    Maheshwari, Ram Krishan; Bidoggia, Benoit; Munk-Nielsen, Stig

    2013-01-01

    The electromagnets in modern particle accelerators require high performance power supply whose output is required to track the current reference with a very high accuracy (down to 50 ppm). This demands very high bandwidth controller design. A converter based on buck converter topology is used...

  4. High Performance Computing and Networking for Science--Background Paper.

    Science.gov (United States)

    Congress of the U.S., Washington, DC. Office of Technology Assessment.

    The Office of Technology Assessment is conducting an assessment of the effects of new information technologies--including high performance computing, data networking, and mass data archiving--on research and development. This paper offers a view of the issues and their implications for current discussions about Federal supercomputer initiatives…

  5. Promoting High-Performance Computing and Communications. A CBO Study.

    Science.gov (United States)

    Webre, Philip

    In 1991 the Federal Government initiated the multiagency High Performance Computing and Communications program (HPCC) to further the development of U.S. supercomputer technology and high-speed computer network technology. This overview by the Congressional Budget Office (CBO) concentrates on obstacles that might prevent the growth of the…

  6. Seeking Solution: High-Performance Computing for Science. Background Paper.

    Science.gov (United States)

    Congress of the U.S., Washington, DC. Office of Technology Assessment.

    This is the second publication from the Office of Technology Assessment's assessment on information technology and research, which was requested by the House Committee on Science and Technology and the Senate Committee on Commerce, Science, and Transportation. The first background paper, "High Performance Computing & Networking for…

  7. Optical interconnection networks for high-performance computing systems.

    Science.gov (United States)

    Biberman, Aleksandr; Bergman, Keren

    2012-04-01

    Enabled by silicon photonic technology, optical interconnection networks have the potential to be a key disruptive technology in computing and communication industries. The enduring pursuit of performance gains in computing, combined with stringent power constraints, has fostered the ever-growing computational parallelism associated with chip multiprocessors, memory systems, high-performance computing systems and data centers. Sustaining these parallelism growths introduces unique challenges for on- and off-chip communications, shifting the focus toward novel and fundamentally different communication approaches. Chip-scale photonic interconnection networks, enabled by high-performance silicon photonic devices, offer unprecedented bandwidth scalability with reduced power consumption. We demonstrate that the silicon photonic platforms have already produced all the high-performance photonic devices required to realize these types of networks. Through extensive empirical characterization in much of our work, we demonstrate such feasibility of waveguides, modulators, switches and photodetectors. We also demonstrate systems that simultaneously combine many functionalities to achieve more complex building blocks. We propose novel silicon photonic devices, subsystems, network topologies and architectures to enable unprecedented performance of these photonic interconnection networks. Furthermore, the advantages of photonic interconnection networks extend far beyond the chip, offering advanced communication environments for memory systems, high-performance computing systems, and data centers.

  8. High Performance Computing and Communications: Toward a National Information Infrastructure.

    Science.gov (United States)

    Federal Coordinating Council for Science, Engineering and Technology, Washington, DC.

    This report describes the High Performance Computing and Communications (HPCC) initiative of the Federal Coordinating Council for Science, Engineering, and Technology. This program is supportive of and coordinated with the National Information Infrastructure Initiative. Now halfway through its 5-year effort, the HPCC program counts among its…

  9. Development and Validation of Reversed Phase High Performance ...

    African Journals Online (AJOL)

    Purpose: To develop and validate a new sensitive and low-cost method for the analysis of amlodipine in tablet dosage form using reversed phase high performance liquid chromatography (RP-HPLC) with ultraviolet (UV) detection. Methods: Standards and samples were prepared by dissolving amlodipine besylate standard ...

  10. Profiling elite/high performance sport athletes with impairments at ...

    African Journals Online (AJOL)

    Worldwide, universities have increasingly become hubs for high performance sports, as student-athletes enter the latter phase of the long-term athlete development process (LTAD). Within the South African context, several universities have and continue to play a significant role in the training and preparation of numerous ...

  11. Spectrum-effect relationships between high performance liquid ...

    African Journals Online (AJOL)

    Purpose: To investigate the spectrum-effect relationships between high performance liquid chromatography (HPLC) fingerprints and duodenum contractility of charred areca nut (CAN) on rats. Methods: An HPLC method was used to establish the fingerprint of charred areca nut (CAN). The promoting effect on contractility of ...

  12. Manufacturing Advantage: Why High-Performance Work Systems Pay Off.

    Science.gov (United States)

    Appelbaum, Eileen; Bailey, Thomas; Berg, Peter; Kalleberg, Arne L.

    A study examined the relationship between high-performance workplace practices and the performance of plants in the following manufacturing industries: steel, apparel, and medical electronic instruments and imaging. The multilevel research methodology combined the following data collection activities: (1) site visits; (2) collection of plant…

  13. Enantioselective determination of sotalol enantiomers in biological fluids using high-performance liquid chromatography.

    Science.gov (United States)

    Shimizu, T; Hiraoka, M; Nakanomyo, H

    1995-12-01

    A simple and sensitive high-performance liquid chromatographic (HPLC) method for the determination of (+)-(S)-sotalol and (-)-(R)-sotalol in biological fluids was established. Following extraction with isopropyl alcohol from biological samples on a Sep-Pak C18 cartridge, the eluent was derivatized with 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosyl isothiocyanate (GITC). The diastereoisomeric derivates were resolved by HPLC with UV detection at 225 nm. Calibration was linear from 0.022 to 4.41 micrograms/ml in human plasma and from 0.22 to 88.2 micrograms/ml in human urine for both (+)-(S)- and (-)-(R)-sotalol. The lower limit of determination was 0.022 microgram/ml for plasma and 0.22 microgram/ml for urine. The within-day and day-to-day coefficients of variation were less than 7.5% for each enantiomer at 0.09 and 1.8 microgram/ml in plasma and at 0.44 and 4.4 micrograms/ml in urine. The method is also applicable to other biological specimens such as rat, mouse and rabbit plasma.

  14. Micropatterned single-walled carbon nanotube electrodes for use in high-performance transistors and inverters.

    Science.gov (United States)

    Kang, Woonggi; Kim, Nam Hee; Lee, Dong Yun; Chang, Suk Tai; Cho, Jeong Ho

    2014-06-25

    We demonstrated the solution-processed single-walled carbon nanotube (SWNT) source-drain electrodes patterned using a plasma-enhanced detachment patterning method for high-performance organic transistors and inverters. The high-resolution SWNT electrode patterning began with the formation of highly uniform SWNT thin films on a hydrophobic silanized substrate. The SWNT source-drain patterns were then formed by modulating the interfacial energies of the prepatterned elastomeric mold and the SWNT thin film using oxygen plasma. The SWNT films were subsequently selectively delaminated using a rubber mold. The patterned SWNTs could be used as the source-drain electrodes for both n-type PTCDI-C8 and p-type pentacene field-effect transistors (FETs). The n- and p-type devices exhibited good and exactly matched electrical performances, with a field-effect mobility of around 0.15 cm(2) V(-1) s(-1) and an ON/OFF current ratio exceeding 10(6). The single electrode material was used for both the n and p channels, permitting the successful fabrication of a high-performance complementary inverter by connecting a p-type pentacene FET to an n-type PTCDI-C8 FET. This patterning technique was simple, inexpensive, and easily scaled for the preparation of large-area electrode micropatterns for flexible microelectronic device fabrication.

  15. Helium exhaust in plasmas with strong radiative edge cooling

    Science.gov (United States)

    Samm, U.; Boedo, J.; Bertschinger, G.; Dippel, K. H.; Euringer, H.; Finken, K. H.; Gray, D.; Hillis, D.; Pospieszczyk, A.; Reiter, D.; Tokar, M.; Unterberg, B.

    1992-12-01

    The compatibility of radiative edge cooling by neon injection and He exhaust with the pump limiter ALT-II is studied on TEXTOR. It is demonstrated that in plasmas with strong auxiliary heating (2 MW NBI) and with the highest average electron densities (¯ ne≈5.5×10 19 m -3) the effective confinement time τ p* for He has a minimum. This good pumping performance is maintained even for cases in which up to 90% of the heating power is radiated from the plasma boundary (cold radiative edge). The processes inside the scoops of the pump limiter (neutral particle transport, re-ionization) and the variation of particle confinement in the main plasma dominate this behavior.

  16. Fast ions and momentum transport in JET tokamak plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Salmi, A.

    2012-07-01

    Fast ions are an inseparable part of fusion plasmas. They can be generated using electromagnetic waves or injected into plasmas as neutrals to heat the bulk plasma and to drive toroidal rotation and current. In future power plants fusion born fast ions deliver the main heating into the plasma. Understanding and controlling the fast ions is of crucial importance for the operation of a power plant. Furthermore, fast ions provide ways to probe the properties of the thermal plasma and get insight of its confinement properties. In this thesis, numerical code packages are used and developed to simulate JET experiments for a range of physics issues related to fast ions. Namely, the clamping fast ion distribution at high energies with RF heating, fast ion ripple torque generation and the toroidal momentum transport properties using NBI modulation technique are investigated. Through a comparison of numerical simulations and the JET experimental data it is shown that the finite Larmor radius effects in ion cyclotron resonance heating are important and that they can prevent fast ion tail formation beyond certain energy. The identified mechanism could be used for tailoring the fast ion distribution in future experiments. Secondly, ASCOT simulations of NBI ions in a ripple field showed that most of the reduction of the toroidal rotation that has been observed in the JET enhanced ripple experiments could be attributed to fast ion ripple torque. Finally, fast ion torque calculations together with momentum transport analysis have led to the conclusion that momentum transport in not purely diffusive but that a convective component, which increases monotonically in radius, exists in a wide range of JET plasmas. Using parameter scans, the convective transport has been shown to be insensitive to collisionality and q-profile but to increase strongly against density gradient. (orig.)

  17. Micro-crack detection in high-performance cementitious materials

    DEFF Research Database (Denmark)

    Lura, Pietro; Guang, Ye; Tanaka, Kyoji

    2005-01-01

    Detection and quantification of microcracks due to autogenous shrinkage in high-performance concrete represents a problematic issue. Techniques based on crack impregnation typically require drying of the samples, which may introduce further cracks. Other non-destructive techniques, such as x......-ray tomography, do not allow sufficient resolution of microcracks. A new technique presented in this paper allows detection of microcracks in cement paste while avoiding artefacts induced by unwanted restraint, drying or temperature variations. The technique consists in casting small circular cylindrical samples...... of high-performance cement pastes in silicone moulds that exert minimal external restraint. Cast-in steel rods with varying diameter internally restrain the autogenous shrinkage and lead to crack formation. Dimensions of the steel rods are chosen so that the size of this restraining inclusion resembles...

  18. High Performance Computing in Science and Engineering '14

    CERN Document Server

    Kröner, Dietmar; Resch, Michael

    2015-01-01

    This book presents the state-of-the-art in supercomputer simulation. It includes the latest findings from leading researchers using systems from the High Performance Computing Center Stuttgart (HLRS). The reports cover all fields of computational science and engineering ranging from CFD to computational physics and from chemistry to computer science with a special emphasis on industrially relevant applications. Presenting findings of one of Europe’s leading systems, this volume covers a wide variety of applications that deliver a high level of sustained performance. The book covers the main methods in high-performance computing. Its outstanding results in achieving the best performance for production codes are of particular interest for both scientists and   engineers. The book comes with a wealth of color illustrations and tables of results.  

  19. Progress on high-performance rapid prototype aluminum mirrors

    Science.gov (United States)

    Woodard, Kenneth S.; Myrick, Bruce H.

    2017-05-01

    Near net shape parts can be produced using some very old processes (investment casting) and the relatively new direct metal laser sintering (DMLS) process. These processes have significant advantages for complex blank lightweighting and costs but are not inherently suited for producing high performance mirrors. The DMLS process can provide extremely complex lightweight structures but the high residual stresses left in the material results in unstable mirror figure retention. Although not to the extreme intricacy of DMLS, investment casting can also provide complex lightweight structures at considerably lower costs than DMLS and even conventional wrought mirror blanks but the less than 100% density for casting (and also DMLS) limits finishing quality. This paper will cover the progress that has been made to make both the DMLS and investment casting processes into viable near net shape blank options for high performance aluminum mirrors. Finish and figure results will be presented to show performance commensurate with existing conventional processes.

  20. High-Performance Photovoltaic Project: Identifying Critical Pathways; Kickoff Meeting

    Energy Technology Data Exchange (ETDEWEB)

    Symko-Davis, M.

    2001-11-07

    The High Performance Photovoltaic Project held a Kickoff Meeting in October, 2001. This booklet contains the presentations given by subcontractors and in-house teams at that meeting. The areas of subcontracted research under the HiPer project include Polycrystalline Thin Films and Multijunction Concentrators. The in-house teams in this initiative will focus on three areas: (1) High-Performance Thin-Film Team-leads the investigation of tandem structures and low-flux concentrators, (2) High-Efficiency Concepts and Concentrators Team-an expansion of an existing team that leads the development of high-flux concentrators, and (3) Thin-Film Process Integration Team-will perform fundamental process and characterization research, to resolve the complex issues of making thin-film multijunction devices.