Science.gov

Sample records for aunapuu lle pechter

  1. LLE Review

    SciTech Connect

    Keck, R.L.

    1992-01-01

    This volume of the LLE Review, covering the period January--March 1992, contains articles on the use of diffraction gratings in laser applications, and the fabrication of gratings for use in these applications. there are two articles on the use of lasers to explore fundamental physics issues and an article on the use of a solid-state diode array for x-ray imaging. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser systems are summarized.

  2. LLE review

    NASA Astrophysics Data System (ADS)

    Bradley, D. K.

    This volume of the LLE Review, covering the period October to December 1989, contains an article discussing saturation effects and power-balance considerations in the design of high-power lasers and an article describing numerical modeling of the effects of power imbalances on target behavior. The advanced technology section reports on the development of a liquid crystal laser-beam apodizer and an experiment to study the high-intensity ionization of noble gases. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized. The highlights of this issue are: The problem of achieving power balance in high-efficiency, multibeam lasers has been studied in terms of gain-saturation effects and the nonlinear nature of harmonic frequency conversion. It is shown that power imbalance can be minimized by balancing the gains and losses in equivalent amplification stages in each beamline. The effects of target implosion behavior of various power-imbalance sources in the OMEGA laser system have been studied using the two-dimensional hydrodynamics code ORCHID. The simulations show good agreement with an experiment in which a deliberate power imbalance was applied to the target drive. Laser-beam apodizers with large clear apertures have been fabricated using cholesteric liquid crystals.

  3. LLE review

    SciTech Connect

    Keck, R.L.

    1991-01-01

    This volume of the LLE Review, covering the period October-December 1991, contains articles on the analysis of argon-filled target experiments, and a theoretical analysis of the impact of nonlocal heat transport in laser filamentation in plasmas. In the Advanced Technology section there is an article on mechanisms that affect thin-film conductivity, and a report on the gain characteristics of the 20-cm SSA prototype amplifier to be used in the OMEGA Upgrade. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized. Highlights of the research reported in this issue are: argon radiation from argon-filled, polymer-shell targets is used as a core-temperature diagnostic and density diagnostic of the surrounding region in a regime where the argon line radiation is strongly absorbed. A theoretical analysis of the impact of nonlocal heat transport on laser filamentation in plasmas is developed. The resulting model is compared with experimental observations and the implications for ICF are discussed. A study of thermal conductivity in thin films seeks to identify mechanisms that result in degradation of thin-film conductivity. Identifying these mechanisms can lead to changes in the thin-film manufacture that will improve their resistance to laser damage.

  4. LLE review

    SciTech Connect

    Bradley, D.K.

    1989-01-01

    This volume of the LLE Review, covering the period October--December 1989, contains an article discussing saturation effects and power-balance considerations in the design of high-power lasers and an article describing numerical modeling of the effects of power imbalances on target behavior. The advanced technology section reports on the development of a liquid crystal laser-beam apodizer and an experiment to study the high-intensity ionization of noble gases. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized. The highlights of this issue are: The problem of achieving power balance in high-efficiency, multibeam lasers has been studied in terms of gain-saturation effects and the nonlinear nature of harmonic frequency conversion. It is shown that power imbalance can be minimized by balancing the gains and losses in equivalent amplification stages in each beamline. The effects of target implosion behavior of various power-imbalance sources in the OMEGA laser system have been studied using the two-dimensional hydrodynamics code ORCHID. The simulations show good agreement with an experiment in which a deliberate power imbalance was applied to the target drive. Laser-beam apodizers with large clear apertures have been fabricated using cholesteric liquid crystals. A soft-edge profile has been achieved by filling a cell with two separate liquid crystals with different selective-reflection bands, and allowing them to partially mix at the interface. A study of the ionization of noble gases in the tunneling regime using high- intensity, 1-ps pulses from the tabletop terawatt laser (T{sup 3}) has been carried out. The measured ion production is well predicted by a Coulomb barrier suppression ionization theory.

  5. LLE Review 101 (October-December 2004)

    SciTech Connect

    Shmayda, W. T.

    2005-03-01

    This volume of the LLE Review, covering October to December 2004, highlights the significance of shaped adiabats to inertial confinement fusion. Theory suggests that inertial confinement fusion (ICF) capsules compressed by shaped adiabats will exhibit improved hydrodynamic stability.

  6. LLE Review 83, Quarterly Report

    SciTech Connect

    2000-12-01

    This volume of the LLE Review, covering April-June 2000, features an article by F. J. Marshall, T. Ohki, D. McInnis, Z. Ninkov, and J. Carbone, who detail the conversion of the OMEGA time-integrated x-ray diagnostics to electronic readout using direct-detection x-ray cameras [charge-injection devices (CID's)]. Pinhole and x-ray microscope images are shown along with inferred calibration measurements of the CID cameras. Currently, the same cameras are being used to obtain x-ray spectra in a TIM-based spectrometer, extending their use to all time-integrated imaging and spectroscopic x-ray instruments used on OMEGA. Additional highlights of the research presented in this issue are: (1) V. A. Smalyuk, B. Yaakobi, F. J. Marshall, and D. D. Meyerhofer investigate the spatial structure of the temperature and density of target-shell plasmas at peak compression (stagnation). This is accomplished by examining the energy dependence of the x-ray emission using narrow-band x-ray filters and the known absorption properties of the shell dopant (Ti). (2) F. Sequin, C. K. Ll, D. G. Hicks, J. A. Frenje, K. M. Green, R. D. Petrasso, J. M. Soures, V. Yu. Glebov, C. Stoeckl, P. B. Radha, D. D. Meyerhofer, S. Roberts, C. Sorce, T. C. Sangster, M. D. Cable, S. Padalino, and K. Fletcher detail the physics and instrumentation used to obtain and interpret secondary D-{sup 3}He proton spectra from current gas-filled-target and future cryogenic-target experiments. Through a novel extension of existing charged-particle detection techniques with track detectors, the authors demonstrate the ability to obtain secondary proton spectra with increased sensitivity. (3) M. Guardelben, L. Ning, N. Jain, D. Battaglia, and K. Marshall compare the utility of a novel liquid-crystal-based, point-diffraction interferometer (LCPDI) with the commercial standard phase-shifting interferometer and conclude that the LCPDI is a viable low-cost alternative. (4) A. B. Shorey, S. D. Jacobs, W. I. Kordonski, and R. F

  7. LLE Review 102 (January-March 2005)

    SciTech Connect

    Shmayda, W.T., ed.

    2005-09-01

    This volume of the LLE Review, covering January–March 2005, features the new “Saturn” target design concept for use in polar direct drive on National Ignition Facility (NIF) while the facility is in its initial, indirect-drive configuration.

  8. LLE Review 120 (July-September 2009)

    SciTech Connect

    Edgell, D.H., editor

    2001-02-19

    This issue has the following articles: (1) The Omega Laser Facility Users Group Workshop; (2) The Effect of Condensates and Inner Coatings on the Performance of Vacuum Hohlraum Targets; (3) Zirconia-Coated-Carbonyl-Iron-Particle-Based Magnetorheological Fluid for Polishing Optical Glasses and Ceramics; (4) All-Fiber Optical Magnetic Field Sensor Based on Faraday Rotation in Highly Terbium Doped Fiber; (5) Femtosecond Optical Pump-Probe Characterization of High-Pressure-Grown Al{sub 0.86}Ga{sub 0.14}N Single Crystals; (6) LLE's Summer High School Research Program; (7) Laser Facility Report; and (8) National Laser Users Facility and External Users Programs.

  9. LLE Review Quarterly Report (January-March 1984). Volume 18

    SciTech Connect

    Lund, L.

    1984-03-01

    This volume of the LLE Review contains articles on the operations of the GDL and OMEGA facilities, energy measurement and beam characterization in the ultraviolet (UV), theoretical calculations of thermal self-focusing in laser plasmas, two aspects of the picosecond optics activities at the LLE, and the NLUF activities during this quarter (January through March 1984).

  10. LLE Review Quarterly Report (January-March 1985). Volume 22

    SciTech Connect

    Kim, H.

    1985-03-01

    This volume of the LLE Review contains articles on completion of frequency conversion of the OMEGA system, recent progress in the laser-fusion effort, certain aspects of the LLE advanced technology program, and the National Laser Users Facility activities for January-March 1985.

  11. LLE Review Quarterly Report (October-December 1984). Volume 21

    SciTech Connect

    Kim, H.

    1984-12-01

    This volume of the LLE Review contains articles on upgrade of the GDL system, theoretical advances in the laser fusion effort, improved target fabrication capabilities, x-ray laser research, developments in the picosecond optics research of the LLE advanced technology program, and on the National Laser Users Facility activities for October-December 1984.

  12. LLE Review 117 (October-December 2008)

    SciTech Connect

    Bittle, W., editor

    2009-05-28

    This volume of the LLE Review, covering October-December 2008, features 'Demonstration of the Shock-Timing Technique for Ignition Targets at the National Ignition Facility' by T. R. Boehly, V. N. Goncharov, S. X. Hu, J. A. Marozas, T. C. Sangster, D. D. Meyerhofer (LLE), D. Munro, P. M. Celliers, D. G. Hicks, G. W. Collins, H. F. Robey, O. L. Landen (LLNL), and R. E. Olson (SNL). In this article (p. 1) the authors report on a technique to measure the velocity and timing of shock waves in a capsule contained within hohlraum targets. This technique is critical for optimizing the drive profiles for high-performance inertial-confinement-fusion capsules, which are compressed by multiple precisely timed shock waves. The shock-timing technique was demonstrated on OMEGA using surrogate hohlraum targets heated to 180 eV and fitted with a re-entrant cone and quartz window to facilitate velocity measurements using velocity interferometry. Cryogenic experiments using targets filled with liquid deuterium further demonstrated the entire timing technique in a hohlraum environment. Direct-drive cryogenic targets with multiple spherical shocks were also used to validate this technique, including convergence effects at relevant pressures (velocities) and sizes. These results provide confidence that shock velocity and timing can be measured in NIF ignition targets, thereby optimizing these critical parameters.

  13. LLE (Laboratory for Laser Energetics) review

    SciTech Connect

    Kumpan, S.A.

    1990-01-01

    This volume of the LLE Review, covering the period July--September 1990, contains articles in two main sections: the OMEGA Upgrade and Advanced Technology Developments. The first article in Section 1 describes the changes in the overall system design of the 60-beam OMEGA Upgrade since the release of the OMEGA Upgrade Preliminary Design Document in October 1989. It is followed by an article that presents results of an investigation into stimulated rotational Raman scattering as it relates to the propagation of high-fluence ultraviolet laser beams in the OMEGA Upgrade. The third article is a report on the energy-transport measurements made on the multisegmented amplifier (MSA), built as a prototype amplifier for the original OMEGA Upgrade system configuration. The final article in Section 1 describes the design of the 20-cm-clear-aperture, single-segmented amplifier (SSA), which will be the final amplifier in the current OMEGA Upgrade system configuration. Section 2 presents the results to date of an intensive in-house effort at LLE to develop the various optical coatings required for the OMEGA Upgrade.

  14. LLE (Laboratory for Laser Energetics) review

    NASA Astrophysics Data System (ADS)

    Kumpan, S. A.

    This volume of the LLE Review, covering the period April to June 1990, contains articles in two main sections, Progress in Laser Fusion and Advanced Technology Developments. The first article presents the theoretical interpretation of the glass-ablator cryogenic-implosion experiments recently conducted on OMEGA. It is followed by an article describing the analysis of neutron time-of-flight data taken during DT and DD experiments; and a discussion of the improvements to laser diagnostics that now provide for precise control of the OMEGA laser is given. This paper contains a report on the development of transparent conductive coatings for KDP crystals, and a discussion of the study of the transient-surface Debye-Waller effect in materials irradiated with an ultrafast laser.

  15. LLE (Laboratory for Laser Energetics) review

    SciTech Connect

    Kumpan, S.A.

    1990-01-01

    This volume of the LLE Review, covering the period April--June 1990, contains articles in two main sections, Progress in Laser Fusion and Advanced Technology Developments. The first article presents the theoretical interpretation of the glass-ablator cryogenic-implosion experiments recently conducted on OMEGA. It is followed by an article describing the analysis of neutron time-of-flight data taken during DT and DD experiments; and a discussion of the improvements to laser diagnostics that now provide for precise control of the OMEGA laser is given. This paper contains a report on the development of transparent conductive coatings for KDP crystals, and a discussion of the study of the transient-surface Debye-Waller effect in materials irradiated with an ultrafast laser.

  16. LLE Review 116 (July-September 2008)

    SciTech Connect

    Marozas, J.A., editor

    2010-03-12

    This issue has the following articles: (1) Optimizing Electron-Positron Pair Production on kJ-Class High-Intensity Lasers for the Purpose of Pair-Plasma Creation; (2) Neutron Yield Study of Direct-Drive, Low-Adiabat Cryogenic D2 Implosions on OMEGA; (3) Al 1s-2p Absorption Spectroscopy of Shock-Wave Heating and Compression in Laser-Driven Planar Foil; (4) A Measurable Lawson Criterion and Hydro-Equivalent Curves for Inertial Confinement Fusion; (5) Pulsed-THz Characterization of Hg-Based, High-Temperature Superconductors; (6) LLE's Summer High School Research Program; (7) FY08 Laser Facility Report; and (8) National Laser Users Facility and External Users Programs.

  17. LLE 2008 annual report, October 2007 - September 2008

    SciTech Connect

    2009-01-31

    The research program at the University of Rochester’s Laboratory for Laser Energetics (LLE) focuses on inertial confinement fusion (ICF) research supporting the goal of achieving ignition on the National Ignition Facility (NIF). This program includes the full use of the OMEGA EP Laser System. Within the National Ignition Campaign (NIC), LLE is the lead laboratory for the validation of the performance of cryogenic target implosions, essential to all forms of ICF ignition. LLE has taken responsibility for a number of critical elements within the Integrated Experimental Teams (IET’s) supporting the demonstration of indirect-drive ignition on the NIF and is the lead laboratory for the validation of the polardrive approach to ignition on the NIF. LLE is also developing, testing, and building a number of diagnostics to be deployed on the NIF for the NIC.

  18. LLE Review Quarterly Report (January-March 1986). Volume 26

    SciTech Connect

    Schmid, A.

    1986-03-01

    This volume of the LLE Review contains reports on OMEGA and GDL laser activities; characterization of laser-generated x-ray sources for nuclear level excitation; the physics of parametric instabilities driven by two pump beams in laser-produced plasmas; developments in advanced technology areas at LLE, specifically ultra-high-speed opto-electronic devices and methods and the modeling of thin-film features in physical vapor deposition; and the National Laser Users Facility activities for January- March 1986.

  19. LLE Review Quarterly Report (October-December 1985). Volume 25

    SciTech Connect

    Schmid, A.

    1985-12-01

    This volume of the LLE Review comprises reports on the performance of the active-mirror-boosted glass development laser (GDL) single-beam system; the implementation of multichannel, soft x-ray diagnostic instrumentation; computer simulation of recent OMEGA laser implosion experiments; materials and ultrafast technology developments in the LLE advanced technology program; and the National Laser Users Facility activities for October-December 1985.

  20. LLE Review 98 (January-March 2004)

    SciTech Connect

    Goncharov, V.N.

    2004-08-10

    This volume of the LLE Review, covering January-March 2004, features ''Performance of 1-THz-Bandwidth, 2-D Smoothing by Spectral Dispersion and Polarization Smoothing of High-Power, Solid-State Laser Beams'', by S. P. Regan, J. A. Marozas, R. S. Craxton, J. H. Kelly, W. R. Donaldson, P. A. Jaanimagi, D. Jacobs-Perkins, R. L. Keck, T. J. Kessler, D. D. Meyerhofer, T. C. Sangster, W. Seka, V.A. Smalyuk, S. Skupsky, and J. D. Zuegel (p. 49). Laser-beam smoothing achieved with 1-THz-bandwidth, two-dimensional smoothing by spectral dispersion and polarization smoothing on the 60-beam, 30-kJ, 351-nm OMEGA laser system is reported. These beam-smoothing techniques are directly applicable to direct-drive ignition target designs for the 192-beam, 1.8-MJ, 351-nm National Ignition Facility. Equivalent-target-plane images for constant-intensity laser pulses of varying duration were used to determine the smoothing. The properties of the phase plates, frequency modulators, and birefringent wedges were simulated and found to be in good agreement with the measurements.

  1. LLE Review Quarterly Report (April-June 1989). Volume 39

    SciTech Connect

    Simon, A.

    1989-06-01

    This volume of the LLE Review, covering the period April-June 1989, includes the second part of a two-part series dealing with the preliminary design of the OMEGA Upgrade. One article provides a general overview of the current upgrade system configuration and another article describes the target system. Future issues of the LLE Review will cover other aspects of the OMEGA Upgrade as the detailed system design develops. In addition, the advanced technology section of this issue contains an article discussing the interaction of a picosecond optical pulse with high temperature superconductors. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  2. LLE Review Quarterly Report (April-June 1986). Volume 27

    SciTech Connect

    Yaakobi, B.

    1986-06-01

    This volume of the LLE Review, covering the period April-June 1986, contains reports on GDL and OMEGA laser activities; analysis of neutron diagnostic methods of compressed laser targets; modeling of non-local heat flow in laser-heated plasmas; and development~ in advanced technology areas at LLE: protective polymeric coatings for nonlinear optical materials, time-resolved observation of electron-phonon relaxation in copper, and non-contact electro-optic sampling of high-speed electrical wave forms with a gallium-arsenide injection laser. Finally, the National Laser Users Facility activities for this period are summarized.

  3. LLE Review 114 (January-March 2008)

    SciTech Connect

    Zuegel, J.D.

    2008-07-30

    This volume of the LLE Review, covering January-March 2008, features 'Cryogenic Targets: Current Status and Future Development', by D. R. Harding, D. H. Edgell, M. D. Wittman, L. M. Elasky, S. J. Verbridge, A. J. Weaver, L. D. Lund, W. Seka, W. T. Shmayda, R. T. Janezic, M. J. Shoup III, M. Moore, R. Junquist, and A. V. Okishev. In this article (p. 57), the authors report on the status of layering cryogenic DT and D{sub 2} targets at LLE for inertial confinement fusion (ICF) targets. This critical effort achieves the important milestone of routinely providing cryogenic DT targets that meet the 1.0-{micro}m (rms) OMEGA ice-quality-surface specification. The best D{sub 2}-ice layers produced so far (rms roughness of 1.1 {micro}m) are approaching the quality typically achieved in DT targets. Efforts to improve the consistency of this process are reported along with investigations supporting the National Ignition Campaign studying issues relevant to indirect-drive and direct-drive cryogenic targets. Additional highlights of recent research presented in this issue include the following: (1) an improved laser speckle smoothing scheme that augments the current NIF 1-D SSD system by using multiple-FM modulators (MultiFM 1-D SSD) (p. 73). With a judicious choice of modulator frequencies, MultiFM 1-D SSD smoothes resonances produced at the higher spatial frequencies and can attain similar or even faster smoothing rates compared to the baseline NIF 2-D SSD system. DRACO simulations have shown that MultiFM 1-D SSD beam smoothing is sufficient for the direct-drive-ignition targets and pulse shapes analyzed thus far, and may even allow reducing the bandwidth enough to eliminate the need for dual-tripler frequency conversion on the NIF. (2) describes a time-gated, monoenergetic proton radiography that provides unique measurements of implosion dynamics of spherical targets in direct-drive inertial confinement fusion (ICF) (p. 81). Radiographs obtained at different implosion times

  4. LLE Review Quarterly Report (October-December 1988). Volume 37

    SciTech Connect

    McKenty, P. W.

    1988-12-01

    This volume of the LLE Review, covering the period October-December 1988, contains several articles devoted to our work in the understanding, identification, and correction of illumination non-uniformities on the OMEGA laser system. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  5. LLE Review Quarterly Report (April-June 1984). Volume 19

    SciTech Connect

    Iwan, L.

    1984-06-01

    This volume of the LLE Review contains articles on the activities in the GDL and OMEGA laser facilities, new theoretical and experimental developments in the physics of laser-produced plasmas, uniformity calculations for a direct-drive fusion reactor, technological advances in picosecond-measurement techniques, and NLUF activities during this quarter (April-June 1984).

  6. LLE Review Quarterly Report (April-June 1985). Volume 23

    SciTech Connect

    Skupsky, S.

    1985-06-01

    This volume of the LLE Review contains articles on the fully UV converted OMEGA laser system, mass-ablation rate experiments, reactor-size target designs, plasma processes in the target corona, degradation in optical performance of dielectric thin films, and the National Laser Users Facility activities for April-June 1985.

  7. LLE 2004 annual report, October 2003-September 2004

    SciTech Connect

    None, None

    2005-01-01

    This report summarizes research at the Laboratory for Laser Energetics (LLE) conducted during the year, operation of the National Laser Users’ Facility (NLUF), a status report of the new OMEGA Extended Performance (EP) laser project, and programs concerning the education of high school, undergraduate, and graduate students during the year.

  8. LLE 2010 Annual Report October 2009 - September 2010

    SciTech Connect

    2011-01-01

    The fiscal year ending September 2010 (FY10) concluded the third year of the third five-year renewal of Cooperative Agreement DE-FC52-08NA28302 with the U.S. Department of Energy (DOE). This annual report summarizes progress in inertial fusion research at the Laboratory for Laser Energetics (LLE) during the past fiscal year including work on the National Ignition Campaign (NIC). It also reports on LLE's progress on laboratory basic science research; laser, optical materials, and advanced technology development; operation of OMEGA and OMEGA EP for the NIC and high-energy density (HED) campaigns, the National Laser Users Facility (NLUF), and for other external users; and programs focusing on the education of high school, undergraduate, and graduate students during the year.

  9. LLE 2007 Annual Report, October 2006 - September 2007

    SciTech Connect

    None, None

    2008-01-31

    The laser-fusion research program at the University of Rochester’s Laboratory for Laser Energetics (LLE) is focused on the National Nuclear Security Administration’s (NNSA’s) Campaign-10 inertial confinement fusion (ICF) ignition and experimental support technology, operation of facilities (OMEGA), and the construction of OMEGA EP -- a high energy petawatt laser system. While LLE is the lead laboratory for research into the direct-drive approach to ICF ignition, it also takes a lead role in certain indirect-drive tasks within the National Ignition Campaign. During this past year progress in the laser-fusion research program was made in three principal areas: OMEGA direct drive and indirect-drive experiments and targets; development of diagnostics for experiments on OMEGA, OMEGA EP, and the National Ignition Facility (NIF); and theoretical analysis and design efforts aimed at improving direct-drive-ignition capsule designs and advanced ignition concepts such as fast ignition and shock ignition.

  10. LLE Review Quarterly Report (July-September 1989). Volume 40

    SciTech Connect

    Knox, R.

    1989-09-01

    This volume of the LLE Review, covering the period July-September 1989, is concerned primarily with uniformity studies. The first article is a report on a series of target experiments with improved irradiation uniformity in which major increases in neutron yields were produced. The first of two articles on theoretical developments presents a new interpretation of burn through experiments, continuing a study reported in LLE Review 35. The second theoretical article suggests a change in distributed phase-plate design that can improve beam uniformity over that achieved with random pattern plates. The fourth and fifth articles report that uniformity in the deposition of DT layers in micro balloons at very low temperatures has been achieved by a temperature-gradient technique, and that aberration free interferograms are now being obtained in the target chamber. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  11. LLE review. Volume 65. Quarterly report, October--December 1995

    SciTech Connect

    Boehly, T.R.

    1996-06-01

    This volume of the LLE Review, covering the period October-December 1995, contains a description of the generation and characterization of continuous, deep-surface-relief phase plates that are more efficient and versatile than previous designs. The LLE program plan has scheduled a number of enhancements to OMEGA`s performance and uniformity, the first of which is the implementation of these new distributed phase plates. Other articles in this volume include the discussion of an x-ray diagnostic method to measure shell-fuel mixing, the theoretical analysis of ablation-front stability, a description of a major subsystem in the OMEGA control system software, a study of the population inversions in intensely pumped Nd:YLF, and a description of a new ultrafast laser system and its uses.

  12. LLE Review Quarterly Report October - December 2011. Volume 129

    SciTech Connect

    Shvydky, Alex

    2011-12-01

    This volume of LLE Review, covering October–December 2011, features “Crossed-Beam Energy Transfer in Direct-Drive Implosions” by I. V. Igumenshchev, W. Seka, D. H. Edgell, D. T. Michel, D. H. Froula, R. S. Craxton, R. Follett, J. H. Kelly, T. Z. Kosc, J. F. Myatt, T. C. Sangster, A. Shvydky, S. Skupsky, and C. Stoeckl (LLE); V. N. Goncharov and A. V. Maximov (LLE and Department of Mechanical Engineering, U. of Rochester); L. Divol and P. Michel (LLNL); and R. L. McCrory and D. D. Meyerhofer (LLE and Departments of Mechanical Engineering and Physics, U. of Rochester). In this article (p. 1), direct-drive–implosion experiments on the OMEGA laser [T. R. Boehly et al., Opt. Commun. 133, 495 (1995)] have shown discrepancies between simulations of the scattered (non-absorbed) light levels and measured ones that indicates the presence of a mechanism that reduces laser coupling efficiency by 10% to 20%. The authors attribute this degradation in laser coupling to crossed-beam energy transfer (CBET)— which is electromagnetically seeded—low-gain stimulated Brillouin scattering. CBET scatters energy from the central portion of the incoming light beam to outgoing light, reducing the laser absorption and hydrodynamic efficiency of implosions. One-dimensional hydrodynamic simulations including CBET show good agreement with all observables in implosion experiments on OMEGA. Three strategies to mitigate CBET and improve laser coupling are considered: the use of narrow beams, multicolor lasers, and higher-Z ablators. Experiments on OMEGA using narrow beams have demonstrated improvements in implosion performance.

  13. LLE Review Quarterly Report (April-June 1988). Volume 35

    SciTech Connect

    Kremens, R.

    1988-06-01

    This volume of the LLE Review, covering the period April-June 1988, contains an in-depth article on recent cryogenic target experiments on the OMEGA laser system; two articles on laser-plasma interactions; and an advanced technology article discussing laser damage in polymeric materials. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  14. LLE Review Quarterly Report (January-March 1988). Volume 34

    SciTech Connect

    Kelly, J.

    1988-03-01

    This volume of the LLE Review, covering the period January-March 1988, contains articles on the spectra of scattered laser radiation from laser-produced plasmas and on the bounce coating of ablation layers on fusion targets. The advanced technology section has reports on a novel technique for characterizing surface breakdown on semiconductor devices and on a versatile alexandrite regenerative amplifier. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  15. LLE 1997. Annual report, October 1996--September 1997

    SciTech Connect

    1998-01-01

    The fiscal year ending September 1997 (FY97) concluded the fifth year of the cooperative agreement (DE-FC03-92SF19460) with the U.S. Department of Energy (DOE). This report summarizes research at the Laboratory for Laser Energetics (LLE) and is the final report for the first five years of the cooperative agreement. In September 1997, the cooperative agreement was renewed for an additional five years. We summarize our research during FY97, the operation of the National Laser Users` Facility (NLUF), and the education of high school, undergraduate, and graduate students in LLE programs. A general introduction to LLE`s experimental physics program and a report on recent results are found on pp. 161-167. This article includes a useful summary of the system`s operational capabilities and system parameters after three years of operation. Direct-drive inertial confinement fusion requires precise drive uniformity, the control of hydrodynamic instabilities during the implosion of the fusion target, and accurate target fabrication and characterization. The article summarizes a wide variety of experiments relating to direct-drive laser fusion, from high-yield implosion experiments to planar and spherical Rayleigh-Taylor experiments, laser-imprinting experiments, and laser-plasma interaction experiments. A detailed analysis of the equation of motion for an electron in a plane wave is presented beginning on p. 24. A guiding center model is postulated and compared to numerical simulation of the actual particle motion. The formula is also verified analytically using the method of multiple scales. Work continues on this formalism to study the effects of the pondermotive force on laser-plasma interactions. A theoretical calculation of the dephasing time of an electron accelerated by a laser pulse is found on pp. 92-100. The trajectory of a charged particle, determined analytically for various pulse shapes, is then used to determine the dephasing time of an accelerated particle.

  16. LLE Review Quarterly Report (July-September 1987). Volume 32

    SciTech Connect

    Donaldson, W.

    1987-09-01

    This volume of the LLE Review, covering the period July-September 1987, contains an article on the measurement of pR in high-compression laser-fusion experiments using secondary reactions. The section on advanced technology has reports on the development of high-repetitionrate active-mirror amplifiers; electro-optic time-domain reflectometry; a new electro-optic finger probe; picosecond high-energy electron diffraction; and a method of using radial transmission lines to obtain very high electric fields. Finally, the activities of the National Laser Users facility and the glass development and OMEGA laser facilities are summarized.

  17. LLE review. Quarterly report, January 1994--March 1994, Volume 58

    SciTech Connect

    Simon, A.

    1994-07-01

    This volume of the LLE Review, covering the period Jan - Mar 1994, contains articles on backlighting diagnostics; the effect of electron collisions on ion-acoustic waves and heat flow; using PIC code simulations for analysis of ultrashort laser pulses interacting with solid targets; creating a new instrument for characterizing thick cryogenic layers; and a description of a large-aperture ring amplifier for laser-fusion drivers. Three of these articles - backlighting diagnostics; characterizing thick cryogenic layers; and large-aperture ring amplifier - are directly related to the OMEGA Upgrade, now under construction. Separate abstracts have been prepared for articles from this report.

  18. LLE Review Quarterly Report (July-September 1986). Volume 28

    SciTech Connect

    Yaakobi, B.

    1986-09-01

    This volume of the LLE Review, covering the period July-September 1986, contains reports on GDL and OMEGA laser activities; generation of timing fiducials on x-ray streak cameras on OMEGA; new theoretical results on the thermodynamic properties of high-density plasmas; experimental results and analysis of target implosions on OMEGA; calculation of thermal self-focusing with multiple laser beams; and test results of multiple x-ray diffraction in crystals. Two reports describe developments in advanced technology: subpicosecond signal propagation on superconducting transmission lines, and progress in two dimensional image processing capabilities. Finally, the National Laser Users Facility activities for this period are summarized.

  19. LLE review. Quarterly report, Volume 69, October--December 1996

    SciTech Connect

    1997-04-01

    This volume of the LLE Review, covering the period October-December 1996, includes a review of 2-D SSD as implemented on the OMEGA laser system. A summary of the detailed mathematical formalism is shown, and the predicted level of uniformity achievable on OMEGA is given. The first experimental results on uniformity using narrow-band 2-D SSD are compared to theoretical calculations. Excellent agreement between experiment and theory is found, which gives confidence that broadband 2-D SSD with polarization wedges should achieve an rms nonuniformity in the 1%-2% level necessary for cryogenic implosion experiments.

  20. LLE Review Quarterly Report (October-December 1987). Volume 33

    SciTech Connect

    Donaldson, W.

    1987-09-01

    This volume of the LLE Review, covering the period October-December 1987, contains descriptions of the implementation of distributed phase plates for improved irradiation uniformity and the implementation of a cryogenic target capability on the OMEGA facility. The section on advanced technology has reports on the design and optimization of recombination x-ray lasers and a near-infrared dichroic dye for use in both active and passive liquid-crystal devices. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  1. LLE Review Quarterly Report (January-March 1989). Volume 38

    SciTech Connect

    McKenty, P. W.

    1989-03-01

    This volume of the LLE Review, covering the period January-March 1989, contains the first part of a two-part series of articles dealing with the OMEGA Upgrade. The two articles in this issue discuss the theoretical and laser design work performed to characterize the basic requirements for the upgrade. In addition, the advanced technology section contains articles discussing a new computer code developed to model x-ray refraction in line-focus geometry and experiments involving the use of time-resolved spectroscopy to diagnose high density in argon implosions. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  2. LLE Review Quarterly Report (April-June 1987). Volume 31

    SciTech Connect

    Donaldson, W.

    1987-06-01

    This volume of the LLE Review, covering the period April-June 1987, contains a summary of the recent high-density campaign on the OMEGA laser system; a report on the absorption and radiation of energy from spherically irradiated targets; and a computer model describing the source of hot spots in the OMEGA laser. The section on advanced technology has reports on a method for accurately measuring the phase of a high power laser and the development of an extremely bright and compact laser. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  3. LLE Review Quarterly Report (July-September 1984). Volume 20

    SciTech Connect

    Iwan, L.

    1984-09-01

    This volume of the LLE Review contains articles on the activities in the GDL and OMEGA laser facilities, some design changes to be implemented on the OMEGA laser, techniques for estimating UV target-irradiation uniformity, progress in fabricating polymer-shell targets, refined estimates of thermal electron transport in IR-irradiated targets, a program to develop a surgical instrument to excise arterial blockages with a laser, a new damage criterion for optical coatings, and NI-UF activities for July-September 1984.

  4. LLE review. Quarterly report, April 1997--June 1997. Volume 71

    SciTech Connect

    1997-10-01

    This volume of the LLE Review, covering the period April-June 1997, includes an article discussing the results from recent experiments performed on OMEGA. These experiments used a new beam-smoothing device-distributed polarization rotators-in concert with existing techniques to improve the on-target uniformity of each beam. The result of this improved radiation uniformity was a substantive reduction in imprinting-the nonuniformity caused by the laser. A novel way to study the time dependence of this imprinting is also presented in this article.

  5. LLE review quarterly report, July--September 1991

    SciTech Connect

    Jaanimagi, P.A.

    1991-01-01

    This volume of the LLE Review, contains articles describing the results of imploding-target burnthrough experiments using smoothing by spectral dispersion (SSD), and a practical nonlocal model for electron transport in laser plasmas. The section on advanced technology includes a report on explosion fraction measurements of water-cooled xenon flashlamps, results on perfluorinated copolymer coatings for high-power laser applications, and a time-resolved study of surface disordering of Pb(110). A brief report reviewing the projects from the high school summer student program is also included. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  6. LLE review quarterly report, July--September 1991. Volume 48

    SciTech Connect

    Jaanimagi, P.A.

    1991-12-31

    This volume of the LLE Review, contains articles describing the results of imploding-target burnthrough experiments using smoothing by spectral dispersion (SSD), and a practical nonlocal model for electron transport in laser plasmas. The section on advanced technology includes a report on explosion fraction measurements of water-cooled xenon flashlamps, results on perfluorinated copolymer coatings for high-power laser applications, and a time-resolved study of surface disordering of Pb(110). A brief report reviewing the projects from the high school summer student program is also included. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  7. LLE Review Quarterly Report (October-December 1990). Volume 45

    SciTech Connect

    Epperlein, E. M.

    1990-12-01

    This volume of the LLE Review, covering the period October-December 1990, contains descriptions of a new phase-conversion technique designed to improve irradiation uniformity, a report on the interpretation of highdensity implosion experiments of argon-filled targets, and an article on the use of absorption spectroscopy to diagnose compressed target layers. The section on advanced technology has a report on the application of KTP crystals as electro-optic amplitude modulators, and describes the use of chirped-pulse technology to measure X(3) by nearly degenerate four-wave mixing. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  8. LLE Review Quarterly Report (April-June 1996). Volume 67

    SciTech Connect

    Skeldon, Mark D.

    1996-06-01

    This volume of the LLE Review, covering the period April-June 1996, contains articles detailing several nonlinear processes associated with lasers and their use, as well as an article describing the computer control systems necessary to maintain and operate a large laser system such as the 60-beam OMEGA laser. The specific topics discussed in this issue include stimulated scattering in laser plasmas, power exchange between interacting laser beams, charged particles interacting with a laser pulse, thermal equilibration of optically excited states, an overview of the laser control system software in OMEGA, and a technique for cancellation of the nonlinear phase accumulation in short-pulse lasers.

  9. LLE 2009 annual report, October 2008-September 2009

    SciTech Connect

    none, none

    2010-01-01

    The fiscal year ending September 2009 (FY2009) concluded the second year of the third five-year renewal of Cooperative Agreement DE-FC52-08NA28302 with the U.S. Department of Energy (DOE). This annual report summarizes progress in inertial fusion research at the Laboratory for Laser Energetics (LLE) during the past fiscal year. It also reports on LLE’s progress on laboratory basic science research; laser, optical materials, and advanced technology development; operation of OMEGA and OMEGA EP for the National Laser Users’ Facility (NLUF), and other external users; and programs focusingon the education of high school, undergraduate, and graduate students during the year.

  10. LLE Review Quarterly Report (July-September 1985). Volume 24

    SciTech Connect

    Skupsky, S.

    1985-09-01

    This volume of the LLE Review contains articles on the first 24-beam UV experiments on the OMEGA laser system, the use of absorption spectroscopy to diagnose high-density compressions, the development of a new target fabrication technique to coat mechanically unsupported laser-fusion targets with a parylene layer, the use of liquid crystals as laser-beam apodizers, the investigation of the process of melting using a subpicosecond probe, the development of a new picosecond oscilloscope, and the National Laser Users Facility activities for June-September 1985.

  11. LLE Review. Quarterly report, January--March 1992: Volume 50

    SciTech Connect

    Keck, R.L.

    1992-09-01

    This volume of the LLE Review, covering the period January--March 1992, contains articles on the use of diffraction gratings in laser applications, and the fabrication of gratings for use in these applications. there are two articles on the use of lasers to explore fundamental physics issues and an article on the use of a solid-state diode array for x-ray imaging. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser systems are summarized.

  12. LLE review: Quarterly report, April--June 1992. Volume 51

    SciTech Connect

    Short, R.W.

    1992-12-31

    This volume of the LLE Review, covering the period April--June 1992, contains articles on laser-plasma interaction experiments in long-scale-length plasmas and on the theory of a new form of the stimulated Brillouin scattering instabilitity. The advanced technology section includes reports on the optical response of superconducting films, the development of high-reflectance transport mirrors for the OMEGA Upgrade, and a new high-brightness mono-mode laser oscillator. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser systems are summarized.

  13. LLE Review Quarterly Report (April-June 1994). Volume 59

    SciTech Connect

    Knauer, James P.

    1994-06-01

    This volume of the LLE Review, covering the period of April-June 1994, contains articles on surface characterization by atomic force microscopy; electron acceleration with intense laser field; spatial intensity variations induced by nonlinear beam propagation; backlighting of implosion targets exhibiting mix; and the use of cosmic rays to monitor large, multielement detectors. Four of these articles - surface characterization; nonlinear beam propagation; backlighting of mixed targets; and monitoring of the MEDUSA detector array - are related to the OMEGA Upgrade, which is currently under construction.

  14. LLE Review Quarterly Report (July-September 2001). Volume 88

    SciTech Connect

    Hinterman, Thomas H.

    2001-09-01

    This volume of the LLE Review, covering July-September 2001, features an article by C. Stoeckl, V. Yu. Glebov, J. D. Zuegel, and D. D. Meyerhofer (p. 171) that describes a simple, low-cost, wide dynamic-range, neutron bang time (NBT) detector. This instrument complements the capabilities of the streak camera-based neutron temporal diagnostic (NTD), which is also installed on the OMEGA laser. The new NBT measures the neutron bang time of D2- and DT-filled inertial confinement fusion (ICF) implosion capsules at neutron yields between 107 and 1011 with an absolute timing accuracy of better than100 ps. This level of accuracy allows the modeling of the implosions to be effectively guided using hydrocode calculations. Other articles in this volume include: Functional Damage Thresholds of Hafnia/Silica Coating Designs for the NIF Laser; High-Gain Direct-Drive Target Designs for the national Ignition Facility; Ultrafast Optoelectronic Interface for Digital Superconducting Electronics; Optimizing the Fabrication of Polyimide Shells; LLE's Summer High School Research Program; FY01 Laser Facility Report; and, National Laser Users' Facility News.

  15. LLE Review quarterly report, January--March 1993. Volume 54

    SciTech Connect

    Meyerhofer, D.D.

    1993-07-01

    This volume of the LLE Review covers the three-month period January--March 1993. The OMEGA laser facility was decommissioned during this quarter to make room for the OMEGA Upgrade laser facility. The decommissioning is described in this volume. Electron thermal transport in the corona and laser-irradiation uniformity are related issues for direct-drive laser fusion. Thermal transport can affect the laser-irradiation uniformity requirements. The status of Fokker-Planck modeling of electron transport at LLE is reviewed and is followed by a description of a new technique for achieving high laser uniformity using zero-correlation phase masks. The use of fast, optically triggered, superconducting opening switches can, in principle, reduce the peak electrical load requirements of systems like the OMEGA Upgrade. Recent research in this area is described. The last three articles discuss vacuum ultraviolet and x-ray emission from short-pulse, laser-matter interactions. The generation of a high spectral brightness, picosecond K{alpha} source is described. The subsequent articles describe the generation of high-order harmonics of a high-intensity laser system laser system in low- density, laser-atom interactions and the novel gas target used.

  16. LLE Review Quarterly Report (July - September 2004). Volume 100

    SciTech Connect

    Schmid, Ansgar W.

    2004-09-01

    The key article in this volume of the LLE Review, covering July-September 2004, addresses "Shock Propagation in Deuterium-Tritium-Saturated Foam" by T. J. B. Collins (LLE) and A. Poludnenko, A. Cunningham, and A. Frank (UR, Department of Physics and Astronomy) (p. 227). Testing the assumption of homogeneous mixing in fibrous foams saturated with cryogenic deuterium and tritium, shock passage in wetted-foam mixtures was simulated by the adaptive-mesh, two-dimensional hydrodynamic code AstroBEAR. For foam fibers of diameter ~1/10 µm and relevant foam densities, the mixing length behind the shock is found to be of the order of microns. Transverse motion dampens out sufficiently that, at the mixing region's edge farthest from the shock, Rankine-Hugoniot jump conditions are obeyed to within a few percent and shock speeds are also within a few percent of their homogeneous values. In addition, questions of feedthrough and feedout are addressed, showing that the stability of the shock front, once it leaves the wetted-foam layer, minimizes the effect of feedthrough. As a result, simulations of whole-foam-pellet implosions may model the wetted foam as a homogeneous mixture.

  17. LLE Review Quarterly Report (October-December 2000). Volume 85

    SciTech Connect

    Sources, John M.

    2000-12-01

    This volume of the LLE Review, covering October-December 2000, begins with an article by R. Betti, M. Umansky, V. Lobatchev, V. N. Goncharov, and R. L. McCrory, who report on the development of a model for the deceleration phase of an imploding inertial fusion capsule (p. 1). The model shows that the ablative flow off the inner shell surface plays a critical role in reducing the growth rate and suppressing short-wavelength modes in the deceleration-phase Rayleigh-Taylor instability. Other articles in this volume are: The Effect of Shock Heating on the Stability of Laser-Driven Targets; Spherical Cavity Expansion in Material with Densification; Design and Performance of a Selectable-Rate Streak-Camera Deflection Ramp Generator; Unique High-Bandwidth, UV Fiber Deliver System for OMEGA Diagnostics Applications; Fabrication and Properties of an Ultrafast NbN Hot-Electron Single-Photon detector; and, Preliminary Design of NIF 2-D SSD.

  18. LLE Review Quarterly Report (April-June 2001). Volume 87

    SciTech Connect

    Hinterman, Thomas H.

    2001-06-01

    This volume of the LLE Review, covering April–June 2001, features ''A Self-Calibrating, Multichannel Streak Camera for Inertial Confinement Fusion Applications'' by Dr. W. R. Donaldson, R. Boni, R. L. Keck, and P. A. Jaanimagi. This article (p. 109) describes the 60-beam streak camera system used on OMEGA and focuses on the hardware and software calibration techniques that maximize its utility. The system can diagnose each of the beams on every target shot and can measure beam energies with 8% accuracy and timing at 7 ps rms. Beam-to-beam power variations of less than 5% can be detected. Other articles in this volume are: Evolution of Shell Nonuniformities Near Peak Compression of a Spherical Implosion; Multibeam Stimulated Brillouin Scattering from Hot Solid-Target Plasmas; Hot-Electron Effect in Superconductors and Is Applications for Radiation Sensors; and, Scaling Law for Marginal Ignition.

  19. LLE review: Quarterly report, July--September 1995. Volume 64

    SciTech Connect

    Craxton, R.S.

    1995-09-01

    This volume of the LLE Review, covering the period July--September 1995, includes a description of the first target experiments performed on the upgraded OMEGA laser system. These experiments, carried out to active and test several diagnostics systems, have demonstrated successful functioning of the overall experimental system and have produced high neutron yields and high core temperatures. Other articles in this volume describe the diagnosis of core conditions using krypton line spectroscopy, a mix model for LILAC that can be applied to study the deceleration instability at the pusher-core interface, a simulated-annealing algorithm for improved phase-plate design, a simple method for characterizing the thickness and uniformity of transparent laser-fusion targets, and femtosecond pump-probe experiments on semiconducting YBCO.

  20. LLE review. Volume 61, Quarterly report, October--December 1994

    SciTech Connect

    1994-12-31

    This volume of the LLE review, covering the period of October--December 1994, contains articles on a diagnostic method employing krypton spectroscopy for measurement of temperature and shell-fuel mixing in high-temperature implosions; the first direct assessment of the ion-acoustic decay instability in a large-scale length, hot plasma; measurements of polarization mode dispersion and group-velocity walkaway in birefringent media using a frequency domain interferometer; an evaluation of the magnetic flux dynamics occurring in an optically triggered, thin-film superconducting switch; the effect of slurry fluid chemistry on particle size distribution during aqueous polishing of optical glass; and the influence of thermal and mechanical processing history in the preparation of well-ordered liquid crystal elastomer systems.

  1. LLE Review quarterly report, January--March 1995. Volume 62

    SciTech Connect

    1995-07-01

    This volume of the LLE review, covering the period of January-March 1995, contains articles on the evaluation of the mechanism for laser damage in OMEGA UV multilayer coatings using a combination of conventional laser-damage characterization methods and atomic force microscopy; a dual-amplitude, fiber-coupled waveguide integrated-optic modulation device for generating temporally shaped optical pulses in OMEGA-, a proposal for modifying the indirect-drive irradiation geometry of the National Ignition Facility (NIF) to provide the additional flexibility for performing direct-drive experiments; direct measurements of terminal-level lifetime in several different Nd:YLF laser media; an overview of the materials science issues, basic mechanisms, and potential device applications for light-emitting porous silicon; and a study of the time-dependent reflection and surface temperatures for laser-irradiated dental hard tissue at two CO{sub 2} laser wavelengths.

  2. LLE Review Quarterly Report (April-June 1998). Volume 75

    SciTech Connect

    Epstein, Reuben

    1998-06-01

    This volume of the LLE Review, covering the period April–June 1998, includes a report on a recent series of experiments, performed by A. Babushkin, M. Guardalben, R. Keck, and W. Seka, that demonstrate a new scheme for converting the infrared light of OMEGA to the third harmonic in the ultraviolet over a bandwidth that is significantly wider than has been previously attainable. This innovative scheme, employing a second tripling crystal in addition to the doubler-tripler pair currently in use, was proposed by D. Eimerl at Lawrence Livermore National Laboratory and adapted to the OMEGA system by S. Craxton and S. Oskoui, a recent participant in LLE’s Summer High-School Research Program. Wider bandwidths on OMEGA will allow the use of broadband beam smoothing with faster smoothing times than have been employed until now.

  3. LLE Review quarterly report, October--December 1992. Volume 53

    SciTech Connect

    Meyerhofer, D.D.

    1992-12-31

    This volume of the LLE Review covers the three-month period October--December 1992. On 18 December, the OMEGA Laser Facility fired its last shot. It will be decommissioned during the next quarter to make room for the OMEGA Upgrade Laser Facility. This volume deals with two areas of interest for the OMEGA Upgrade, the development of advanced x-ray and neutron diagnostics and the development of long-pulse (>1-ns) laser sources. The first three articles discuss the development of time-dependent diagnostics. The development of an x-ray framing camera is described and measurements of the high-voltage pulse propagation in the camera are presented. Time-resolved and time-integrated neutron diagnostics for the OMEGA Upgrade are then discussed. Two schemes for the generation of >1-ns laser pulses are presented. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  4. LLE Review Quarterly Report (October-December 1999). Volume 81

    SciTech Connect

    Radha, P. B.

    1999-12-01

    This volume of the LLE Review, covering the period October–December 1999, includes a report on the stability of direct-drive NIF capsules. V. N. Goncharov, R. Betti, J. A. Delettrez, P. W. McKenty, S. Skupsky, and R. P. J. Town examine the conditions under which direct-drive NIF capsules ignite. Their numerical study uses two-dimensional hydrodynamic simulations in conjunction with a model that includes the various mechanisms that can influence target performance. Inner-surface roughness of the DT ice of the direct-drive cryogenic capsules and laser nonuniformities have been identified as the principal seeds of the instabilities that can potentially quench ignition. The authors conclude that a target gain greater than 10 can be achieved for a realistic inner-surface ice roughness when beam smoothing with 2-D SSD and a bandwidth greater than 0.5 THz is used.

  5. LLE Review Quarterly Report (July-September 1988). Volume 36

    SciTech Connect

    Kremens, R.

    1988-09-01

    This volume of the LLE Review, covering the period July-September 1988, contains several articles on important diagnostics used during a recent high-density target experiment series; a report on a novel technique for improving laser illumination uniformity on laser-fusion experiments; and a report on non local electron transport simulations as applied to laser produced plasmas. The advanced technology section has an article discussing multiphoton ionization using the T3 (table-top-terrawatt) laser system; and a discussion of a new computer code to model x-ray refraction in line-focus geometry. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized.

  6. LLE Review Quarterly Report (January-March 2001). Volume 86

    SciTech Connect

    Sources, John M.

    2001-03-01

    This volume of LLE Review, covering January-March 2001, includes a report on the characterization of direct-drive implosion core conditions using time-resolved Ar K-shell spectroscopy. This work was carried out by a team that included S. P. Regan, J. A. Delettrez, P. A. Jaanimagi, B. Yaakobi, V. A. Smalyuk, F. J. Marshall, D. D. Meyerhofer, and W. Seka of the Laboratory for Laser Energetics (LLE), University of Rochester; D. A. Haynes, Jr. of the Department of Engineering Physics, University of Wisconsin; and C. F. Hooper, Jr. of the Department of Physics, University of Florida. The experiments involved the implosion of polymer shells filled with Ar-doped deuterium gas driven with up to 24-kJ, 1-ns square laser pulses smoothed with 1-THz, 2-D smoothing by spectral dispersion (SSD) and polarization smoothing (PS). The emissivity-averaged core electron temperature and density were inferred from the measured time-dependent Ar K-shell spectral line shapes. Electron densities in excess of 2.5 × 1024 cm-3 and electron temperatures ~2.5 keV were measured in these experiments. This represents the highest combination of electron temperature and density measured for these types of implosions in laser-driven inertial fusion experiments. Other articles in this volume are titled: Study of Direct-Drive, DT-Gas-Filled-Plastic-Capsule Implosions Using Nuclear Diagnostics on OMEGA; A Consistent Measurement-Based Picture of Core-Mix in Direct-Drive Implosions on OMEGA; High-Resolution Neutron Imaging of Laser-Imploded DT Targets; The Smoothing Performance of Ultrafast Pickets on the NIF; Tests of EXAFS on OMEGA: Feasibility for Shock Heating Measurements; and, Microhardness and Indention Fracture of Potassium Dihydrogen Phosphate (KDP).

  7. LLE review. Quarterly report, July 1997--September 1997

    SciTech Connect

    1998-02-01

    This volume of the LLE Review, covering the period July--September 1997, begins with a general introduction to LLE`s experimental physics program and a report on recent results. This article includes a useful summary of the system`s operational capabilities and system parameters. Other highlights of the wide variety of research presented in this issue are: a promising method to directly observe the cold compressed shell of an imploding target. The shell is normally observed by backlighting. The proposal described here is to use a high-Z dopant that fluoresces under radiation from the hot core in the K{alpha} line. A study of the instabilities associated with near-forward stimulated Brillouin scattering. It includes a calculation of the saturation times and steady-state gain exponents. A successful program of pulse shaping for the OMEGA laser system. Examples of a variety of pulse shapes that can be programmed are presented. A description of the angular-scattering characteristics of ferroelectric liquid crystal electro-optical devices operating in transient and extended scattering modes. The possibility of applying these devices as modulators in practical IR imaging systems is evaluated. A faster method of shaping and finishing IR materials by the use of magnetorheological fluids. Detailed specifications and test results are included. An integrated circuit tester based on interferometric imaging. This technique holds promise of ultrafast noninvasive testing of the voltage states of sections of microchips. Continued success of the Laboratory`s High School Summer Research Program. The program, which started in 1989, has brought several dozen young people into intimate contact with modern science and technology. The volume concludes with a Laser Facility Report and the National Laser Users` Facility News.

  8. LLE Review. Volume 68, July--September 1996

    SciTech Connect

    1996-07-01

    This volume of the LLE Review, covering the period of July-September 1996, includes a description of an important experiment carried out on OMEGA by researchers from LANL, LLNL, and LLE to demonstrate the feasibility of using OMEGA for indirect drive. Additional topics include tetrahedral hohlraums, the speckle properties of phase- converted laser beams, design criteria for SSD phase modulators, and the design of slab amplifiers. Highlights of the research presented in this issue are (1) Results from the proof-of-principle indirect- drive experiments in which up to 40 OMEGA beams were used to irradiate cylindrical hohlraums. Nova results were reproduced, and new capabilities not available on other lasers were demonstrated. (2) A discussion of tetrahedral hohlraums (spherical hohlraums with four laser entrance holes) as a means of achieving better capsule irradiation uniformity. Tetrahedral hohlraums also allow the use of all 60 OMEGA beams and may provide an alternate route to ignition on the NIF. (3) An analysis of the residual target irradiation nonuniformity due to the fine laser speckle remaining on the beam after being phase converted by the DPP`s. A model shows how a uniformly ablating plasma atmosphere reduces the speckle contribution to the effective time-averaged irradiation nonuniformity. (4) A discussion of the theory, design, manufacture, testing, and implementation of the microwave SSD phase modulators used on OMEGA for two-dimensional SSD. The modulators are capable of operating in the gigahertz frequency range. (5) A discussion of the design and performance of a large-aperture, high-gain Nd:glass zig-zag slab amplifier for materials testing. The design incorporates improvements from previous work in addition to improvements obtained from careful design choices guided by analytic calculations.

  9. LLE Review Quarterly Report (July-September 1998). Volume 76

    SciTech Connect

    Epstein, Reuben

    1998-09-01

    This volume of the LLE Review, covering the period July-September 1998, includes reports on two of the newest subsystems in the OMEGA laser facility. A. V. Okishev, M. D. Skeldon, and W. Seka have developed a highly stable, diode-pumped Nd:YLF master oscillator for the OMEGA laser system. This new master oscillator produces either single-frequency Q-switched pulses or cw radiation for the OMEGA pulse-shaping system. The switch-over between these two regimes requires no laser realignment. The new master oscillator is completely computer controlled and has been operating continuously in OMEGA for six months without operator intervention. A. Babushkin, W. Bittle, S. A. Letzring, M. D. Skeldon, and W. Seka have designed a negative-feedback–controlled regenerative amplifier that has been part of the OMEGA laser system for the past two years. The negative feedback makes the energy output of the regenerative amplifier stable and insensitive to the variations in pulse energy. This amplifier’s long-term output energy stability is the highest ever demonstrated for a millijoule-level laser system, either flashlamp pumped or diode pumped. Other articles in this volume are titled: Transcient Bandwidth Analysis of Photoconductive Microwave Switches Implemented in the OMEGA Pulse-Shaping System; Simulations of Near-Field Intensity Modulations in High-Intensity Laser Beams due to Self- and Cross-Phase Modulation Between Orthogonally Polarized Laser Beams Emerging from a Diamond-Turned KDP Wedge; X-Ray Radiographic System Used to Measure the Evolution of Broadband Imprint in Laser-Driven Planar Targets; Collisionless Damping of Localized Plasma Waves in Laser-Produces Plasmas and Application to Stimulated Raman Scattering in Filaments; LLE's Summer High School Research Program; FY98 Laser Facility Report; and, National Laser Users' Facilty News.

  10. LLE Review Quarterly Report (October - December 2007). Volume 113

    SciTech Connect

    Zuegel, Jonathan D.

    2007-12-01

    This volume of the LLE Review, covering October–December 2007, features “High-Intensity Laser–Plasma Interactions in the Refluxing Limit,” by P. M. Nilson, W. Theobald, J. Myatt, C. Stoeckl, M. Storm, O. V. Gotchev, J. D. Zuegel, R. Betti, D. D. Meyerhofer, and T. C. Sangster. In this article (p. 1), the authors report on target experiments using the Multi-Terawatt (MTW) Laser Facility to study isochoric heating of solid-density targets by fast electrons produced from intense, short-pulse laser irradiation. Electron refluxing occurs due to target-sheath field effects and contains most of the fast electrons within the target volume. This efficiently heats the solid-density plasma through collisions. X-ray spectroscopic measurements of absolute Kα (x-radiation) photon yields and variations of the Kβ/Kα b emission ratio both indicate that laser energy couples to fast electrons with a conversion efficiency of approximately 20%. Bulk electron temperatures of at least 200 eV are inferred for the smallest mass targets.

  11. LLE Review Quarterly Report (January-March 1993). Volume 54

    SciTech Connect

    Meyerhofer, D. D.

    1993-03-01

    This volume of the LLE Review covers the three-month period January-March1993. The OMEGA laser facility was decommissioned during this quarter to make room for the OMEGA Upgrade laser facility. The decommissioning is described in this volume. Electron thermal transport in the corona and laserirradiation uniformity are related issues for direct-drive laser fusion. Thermal transport can affect the laser-irradiation uniformity requirements. The status of Fokker-Planckmodeling of electron transport at LLEis reviewed and is followed by a description of a new technique for achieving high laser uniformity using zero-correlation phase masks. The use of fast, optically triggered, superconducting opening switches can, in principle, reduce the peak electrical load requirements of systems like the OMEGA Upgrade. Recent research in this area is described. The last three articles discuss vacuum ultraviolet and x-ray emission from shortpulse, laser-matter interactions. The generation of a high spectral brightness, picosecond K, source is described.The subsequent articles describe the generation of high-order harmonics of a high-intensity laser system in low-density, laseratom interactions and the novel gas target used.

  12. LLE 1995 annual report, October 1994--September 1995

    SciTech Connect

    1996-01-01

    The fiscal year ending September 1995 (FY95) concluded the third year of the cooperative agreement (DE-FC03-92SF19460) with the U.S. Department of Energy (DOE). This report summarizes research at the Laboratory for Laser Energetics (LLE) and reports on the successful completion of the OMEGA Upgrade. Previous annual reports describe the OMEGA Upgrade design. The preliminary design for the system was complete in October 1989 and the detailed design started in October 1990. The original 24-beam OMEGA system was decommissioned in December 1992 as construction for the OMEGA Upgrade began. We discuss the initial performance results (p. 99) of the upgraded OMEGA laser system. All acceptance tests were completed, and we demonstrated that all 60 beams can irradiate a target with more energy and better beam balance than was required by DOE`s acceptance criteria. We are most proud that all program milestones were met or exceeded, and that the system was completed on time and on budget.

  13. LLE Review Quarterly Report (January-March 2000). Volume 82

    SciTech Connect

    Radha, P. B.

    2000-03-01

    This volume of the LLE Review, covering the period January-March 2000, includes a report on OMEGA cryogenic target designs for the soon-to-be-commissioned OMEGA Cryogenic Target Handling System. R. P. J. Town, J. A. Delettrez, R. Epstein, V. N. Goncharov, P. W. McKenty, P. B. Radha, and S. Skupsky use two-dimensional hydrodynamic simulations in conjunction with a stability analysis model to study the performance of OMEGA cryogenic capsules. They show that these targets are energy-scaled from the NIF ignition designs and have similar 1-D behavior and stability properties. This similarity will facilitate the extrapolation of cryogenic target studies on OMEGA to ignition targets on the NIF. Other articles in this volume are: Imprint Reduction using an Intensity Spike in Omega Cryogenic Targets; Measurement of Preheat Due to Fast Electrons in Laser Implosions; Holographic Transmission Gratings for Spectral Dispersion; Laser Beam Smoothing Caused by the Small-Spatial-Scale B-Integral; Three-Dimensional Modeling of Capsule Implosions in OMEGA Tetrahedral Hohlraums; and, Nanoindentation Hardness of Particles Used in Magnetoheological finishing (MRF).

  14. LLE Review Quarterly Report (October-December 2001). Volume 89

    SciTech Connect

    Donaldson, William R.

    2001-12-01

    This volume of the LLE Review, covering October-December 2001, features “Time-Integrated Light Images of OMEGA Implosions” by P. Morley and W. Seka (p. 1). E. Kowaluk initiated this project for aesthetic rather than scientific reasons when he began taking visible light photographs of imploding OMEGA targets. These beautiful images are used to communicate LLE’s mission to the general public. A closer examination of the images revealed a one-to-one correspondence between the bright spots in the image and each of the 60 laser beams. The intensity of the bright spots has been related to refraction and absorption in the plasma surrounding the imploding target. These photographs are now proving to be the basis of a new laser-plasma interaction diagnostic. Other articles in this volume are titled the following: Analytical Model of Nonlinear, Single-Mode, Classical Rayleigh-Taylor Instability at Arbitrary Atwood Numbers; A High-Pass Phase Plate Design for OMEGA and the NIF; Advanced Tritium Recovery System; Establishing Links Between Single Gold Nanoparticles Buried Inside SiO2 Thin Film and 351-nm Pulsed-Laser-Damage Morphology; Resistive Switching Dynamics in Current-Biased Y-Ba-Cu-O Microbridges Excited by Nanosecond Electrical Pulses; and, Properties of Amorphous Carbon Films.

  15. LLE Review Quarterly Report (July-September 1991). Volume 48

    SciTech Connect

    none,

    1991-09-01

    This report was prepared as an account of work conducted by the Laboratory for Laser Energetics and sponsored by New York State Energy Research and Development Authority, the University of Rochester, the U.S. Department of Energy, and other agencies. Neither the above-named sponsors, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed. or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, mark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof or any other sponsor. Results reported in the LLE Review should not be taken as necessarily final results as they represent active research. The views and opinions of authors expressed herein do not necessarily state or reflect those of any of the above sponsoring entities.

  16. LLE review. Quarterly report, October--December 1991: Volume 49

    SciTech Connect

    Keck, R.L.

    1991-12-31

    This volume of the LLE Review, covering the period October-December 1991, contains articles on the analysis of argon-filled target experiments, and a theoretical analysis of the impact of nonlocal heat transport in laser filamentation in plasmas. In the Advanced Technology section there is an article on mechanisms that affect thin-film conductivity, and a report on the gain characteristics of the 20-cm SSA prototype amplifier to be used in the OMEGA Upgrade. Finally, the activities of the National Laser Users Facility and the GDL and OMEGA laser facilities are summarized. Highlights of the research reported in this issue are: argon radiation from argon-filled, polymer-shell targets is used as a core-temperature diagnostic and density diagnostic of the surrounding region in a regime where the argon line radiation is strongly absorbed. A theoretical analysis of the impact of nonlocal heat transport on laser filamentation in plasmas is developed. The resulting model is compared with experimental observations and the implications for ICF are discussed. A study of thermal conductivity in thin films seeks to identify mechanisms that result in degradation of thin-film conductivity. Identifying these mechanisms can lead to changes in the thin-film manufacture that will improve their resistance to laser damage.

  17. LLE Review Quarterly Report (January-March 2002). Volume 90

    SciTech Connect

    Donaldson, William R.

    2002-03-01

    This volume of the LLE Review, covering January-March 2002, features “First Results from Cryogenic Target Implosions on OMEGA” by C. Stoeckl et al. (p. 49). This article describes initial results from direct-drive spherical cryogenic target implosions on the 60-beam OMEGA laser system. These experiments are part of the scientific base leading to direct-drive ignition implosions planned for the National Ignition Facility (NIF). Results shown include neutron yield, secondary-neutron and proton yields, the time of peak neutron emission, and both time-integrated and time-resolved x-ray images of the imploding core. The experimental values are compared with 1-D numerical simulations. The target with an ice-layer nonuniformity of srms = 9 mm showed 30% of the 1-D predicted neutron yield. These initial results are encouraging for future cryogenic implosions on OMEGA and the NIF. Other articles in this issue are titled the following: Equation-of-State Measurements of Porous Materials on OMEGA: Numerical Modeling; Observations of Modulated Shock Waves in Solid Targets Driven by Spatially Modulated Laser Beams; Time-Dependent Electron Thermal Flux Inhibition in direct-Drive Laser Implosions; Precision Spectral Sculpting of Broadband FM Pulses Amplified in a Narrowband Medium; Electric-Field-Induced Motion of Polymer Cholesteric Liquid Crystal Flakes in a Moderately Conductive Fluid; and, Femtosecond Response of a Freestanding LT-GaAs Photoconductive Switch.

  18. LLE Review quarterly report, July--September 1992. Volume 52

    SciTech Connect

    Short, R.W.

    1992-12-31

    This volume of the LLE Review, covering the period July--September 1992, contains articles on methods of balancing the beam power on the OMEGA Upgrade and on the damping of ion-sound waves in laser-produced plasmas. The advanced technology section includes reports on optical nonlinearities in high-temperature superconductors, a method of increasing gas retention time for laser-fusion targets, and a study of stimulated Raman scattering of laser beams in air. Highlights of the research reported in this issue are: An efficient method has been developed for balancing the power in the 60 beams of the OMEGA Upgrade. The method can achieve 2% power balance for both main and foot beams using only four system shots. A study of ion-sound-wave damping has substantially revised and expanded our knowledge of this effect. The damping of ion waves can have important consequences for laser-plasma interaction. The use of femtosecond laser pulses to study the properties of thin-film, high-temperature superconductors is discussed. A method for increasing the gas retention time of polymer-shell laser-fusion targets by overcoating them with a thin layer of aluminum is described. A code has been developed to study stimulated rotational Raman scattering in high-power laser beams propagating through air.

  19. LLE Review Quarterly Report (January-March 1999). Volume 78

    SciTech Connect

    Regan, Sean P.

    1999-03-01

    This volume of the LLE Review, covering the period January-March 1999, features two articles concerning issues relevant to 2-D SSD laser-beam smoothing on OMEGA. In the first article J. D. Zuegel and J. A. Marozas present the design of an efficient, bulk phase modulator operating at approximately 10.5 GHz, which can produce substantial phase-modulated bandwidth with modest microwave drive power. This modulator is the cornerstone of the 1-THz UV bandwidth operation planned for OMEGA this year. In the second article J. A. Marozas and J. H. Kelly describe a recently developed code -- Waasese -- that simulates the collective behavior of the optical components in the SSD driver line. The measurable signatures predicted by the code greatly enhance the diagnostic capability of the SSD driver line. Other articles in this volume are titled: Hollow-Shell Implosion Studies on the 60-Beam, UC OMEGA Laser System; Simultaneous Measurements of Fuel Areal Density, Shell Areal Density, and Fuel Temperature in D3He-Filled Imploding Capsules; The Design of Optical Pulse Shapes with an Aperture-Coupled-Stripline Pulse-Shaping System; Measurement Technique for Characterization of Rapidly Time- and Frequency-Varying Electronic Devices; and, Damage to Fused-Silica, Spatial-Filter Lenses on the OMEGA Laser System.

  20. Late language emergence in 24 month twins: Heritable and increased risk for LLE in twins

    PubMed Central

    Rice, Mabel L.; Zubrick, Stephen R.; Taylor, Catherine L.; Gayán, Javier; Bontempo, Daniel E.

    2013-01-01

    Purpose This study investigated the etiology of Late Language Emergence (LLE) in 24-month-old twins considering possible twinning, zygosity, gender, and heritability effects for vocabulary and grammar phenotypes. Method A population-based sample of 473 twin pairs participated. Multilevel modelling estimated means and variances of vocabulary and grammar phenotypes, controlling for familiality. Heritability was estimated with DeFries-Fulker regression, and variance components models, to determine effects of heritability, shared-environment, and non-shared environment. Results Twins had lower average language scores than norms for singleborn children, with lower average performance for MZ than DZ twins, and lower for boys than girls, although gender and zygosity did not interact. Gender did not predict LLE. Significant heritability was detected for vocabulary (.26) and grammar phenotypes (.52/.43 for males/females) in the full sample, and in the sample selected for LLE (.42 and .44). LLE and the appearance of Word Combinations were also significantly heritable (.22-.23). Conclusion The findings revealed an increased likelihood of LLE in twin toddlers compared to singleborn children that is modulated by zygosity and gender differences. Heritability estimates are consistent with previous research for vocabulary and add further suggestion of heritable differences in early grammar acquisition. PMID:24167238

  1. LLE Review Quarterly Report July-September 2000

    SciTech Connect

    2000-12-01

    This volume of the LLE Review, covering July-September 2000, begins with an article by T. R. Boehly, V. N. Goncharov, O. Gotchev, J. P. Knauer, D. D. Meyerhofer, D. Oron, S. P. Regan, Y. Srebro, W. Seka, D. Shvarts, S. Skupsky, and V.A. Smalyuk, who describe measurements of the effect of beam smoothing and pulse shape on imprinting. (Imprinting is defined as the imposition of pressure perturbations on the target by spatial variations in the laser intensity.) A principal result is the observation of reduced levels of imprint with the higher beam smoothing afforded by 1-THz smoothing by spectral dispersion (SSD). Additional highlights of research presented in this issue are: (1) P. W. McKenty, V. N. Goncharov, R. P. J. Town, S. Skupsky, R. Betti, and R. L. McCrory describe calculations of directly driven ignition capsule performance on the National Ignition Facility (NIF). The authors detail how the various contributors to implosion disruption (laser imprint, power imbalance, and target roughness) affect target performance and final gain. The conclusions are obtained by examining the simulated target evolution with the two-dimensional hydrodynamics computer code ORCHID. (2) D. D. Meyerhofer, J. A. Delettrez, R. Epstein, V. Yu. Glebov, V. N. Goncharov, R. L. Keck, R. L. McCrory, P. W. McKenty, F. J. Marshall, P. B. Radha, S. P. Regan, S. Roberts, W. Seka, S. Skupsky, V. A. Smalyuk, C. Sorce, C. Stoeckl, J. M. Soures, R. P. J. Town, B. Yaakobi, J. D. Zuegel, J. Frenje, C. K. L1,R. D. Petrasso, F. Seguin, K. Fletcher, S. Padalino, C. Freeman, N. Izumi, R. Lerche, T. W. Phillips, and T. C. Sangster describe the results of a series of direct-drive implosions of gas-fusion-fuel-filled plastic shells performed on the OMEGA laser system. The experiments include those performed with 1-THZ SSD and high-quality power balance. (3) V. Yu. Glebov, D. D. Meyerhofer, C. Stoeckl, and J. D. Zuegel describe the technique of measuring secondary neutron yield (DT neutron yield from D

  2. LLE review, Volume 77. Quarterly report, October--December 1998

    SciTech Connect

    Regan, S.P.

    1998-12-31

    This volume of the LLE Review, covering the period October--December 1998, includes two articles addressing issues applicable to direct-drive ICF on the National Ignition Facility (NIF): laser-plasma interactions and laser-irradiation uniformity. Additional highlights of the research presented in this issue are: (1) P.B. Radha and S. Skupsky present a novel charged-particle diagnostic that performs simultaneous {rho}R measurements of the fuel, shell, and ablator regions of a compressed ICF target, consisting of an inner DT fuel region, a plastic (CH) shell, and an ablator (CD), by measuring the knock-on deuteron spectrum. (2) F. Dahmani, S. Burns, J. Lambropoulos, S. Papernov, and A. Schmid report results from stress-inhibited laser-driven crack propagation and stress-delayed damage-initiation experiments in fused silica at 351 nm. Research is underway presently to determine the ramifications of these findings for large-aperture systems, such as OMEGA. (3) V. Goncharov presents an analytic theory of the ablative Richtmyer-Meshkov instability, which shows that the main stabilizing mechanism of the ablation-front perturbations is the dynamic overpressure of the blowoff plasma with respect to the target material. The perturbation evolution during the shock transit time is studied to determine the initial conditions for the Rayleigh-Taylor phase of the instability and to analyze the level of laser imprint on ICF direct-drive targets. (4) J.M. Larkin, W.R. Donaldson, T.H. Foster, and R.S. Knox examine the triplet state of rose bengal, a dye used in photodynamic therapy, that is produced by 1,064-nm excitation of T{sub 1}. (5) R. Adam, M. Currie, R. Sobolewski, O. Harnack, and M. Darula report measurements of the picosecond photoresponse of a current-biased YBCO microbridge coupled to a bicrystal YBCO Josephson junction.

  3. LLE Review quarterly report July--September 1993. Volume 56

    SciTech Connect

    Hutchison, R.J.

    1993-12-31

    This volume of the LLE Review, covering the period July--September 1993, contains articles on self-focusing of broad-bandwidth laser light with angular dispersion, laser patterning of thin-film circuits, and construction of foam-shell fusion targets. Reports on the detailed designs of major subsystems of the OMEGA Upgrade and on the continuing activation of the upgraded Glass Development Laser system are summarized. Descriptions of research proposals for NLUF are also included in this issue. Highlights of the research reported in this issue are: Previous investigations of self-focusing behavior of broad-bandwidth laser light without angular dispersion showed only slight differences when compared to laser light with angular dispersion. A new, numerical investigation of self-focusing with applied angular dispersion shows the development of transverse amplitude modulation, which can act to enhance or impede instantaneous self-focusing. Averaging over one period of phase modulation with imposed bandwidth shows consistent smoothing of the beam, nearly replicating the original spatial profile, including smoothing of induced perturbations due to laser-system imperfections. A continuous-wave argon-ion laser beam is focused onto a Y-Ba-Cu-O thin-film circuit. The laser beam selectively heats the epitaxy, which enriches oxygen in irradiated regions alongside depleted regions. Oxygen enrichment results in the formation of superconducting regions, while oxygen depletion results in semiconducting regions. This maskless operation yields applications in microbridges,coplanar transmisson lines, field-effect transistors, and photoconductive switches. One technique to form thick fusion fuel layers is to use a low-density polymer or aerosol foam matrix to hold the liquid DT. This issue summarizes the results of a collaborative experiment conducted at the Institute for Laser Engineering (ILE) to fabricate foam-shell targets with plastic-layer overcoats.

  4. [Neurousurpation--the expropriation and suppression of Dölle's neurobiological pioneer work].

    PubMed

    Bertram, Wulf

    2011-08-01

    The discovery of a hitherto unpublished dissertational thesis in the archive of a publishing house has lead to a lost publication by Ernst August Dölle. In this manuscript, the author reports on the stimulation of a cerebral libido area in the dog, long before Olds and Milner published their work on the discovery of the rewarding area. The reasons for the suppression of this early publication by Dölle are investigated and are ascribed to an effort to use his neurobiologic research for secret mental manipulation experiments of the CIA at the beginning of the Cold War. PMID:21823065

  5. LLE Review Quarterly Report (April-June 2005). Volume 103

    SciTech Connect

    Myatt, Jason

    2005-06-01

    This volume of the LLE Review, covering April-June 2005, features the following articles. ''High-Density and High ρR Fuel Assembly for Fast-Ignition Inertial Confinement Fusion'' by R. Betti and C. Zhou. In this article (p. 117), the authors optimize implosion parameters for fast-ignition inertial confinement fusion and design fast-ignition targets relevant to direct-drive inertial fusion energy (IFE). It is shown that a 750-kJ laser can assemble fuel with VI = 1.7 X 107 cm/s, a = 0.7, t = 400 g/cc, tR = 3 g/cm2, and a hot-spot volume of less than 10% of the compressed core. If fully ignited, this fuel assembly can produce energy gains of 150. In the second article (p. 122), C. Stoeckl, T. R. Boehly, J. A. Delettrez, V. Yu. Glebov, J. Miller, V. A. Smalyuk, W. Theobald, B. Yaakobi, and T. C. Sangster, along with J. A. Frenje, C. K. Li, R. D. Petrasso, and F. H. Séguin (MIT), S. P. Hatchett (LLNL), and R. B. Stephens (GA) describe recent OMEGA experiments that have studied the fuel assembly of gas-filled, cone-in-shell, fast-ignition targets. Using both fusion products and backlit images, an areal density of ~60-70 mg/cm2 was inferred for the dense core assembly. The results are promising for successful integrated fast-ignition experiments on the OMEGA EP facility, scheduled to be completed in 2007. Other articles are titled ''Planar Cryogenic Target Hangling Capability for the OMEGA Laser-Fusion Facility''; "Fourier-Space, Nonlinear Rayleigh-Taylor Growth Measurements of 3-D Laser-Imprinted Modulations in Planar Targets''; ''Technologies for Mitigating Tritum Releases to the Environment''; ''All-Solid-State, Diode-Pumped, Multiharmonic Laser System for Timing Fiducial''; and ''EXAFS Measurement of Iron bcc-to-hcp Phase Transformation in Nanosecond-Laser Shocks''.

  6. LLE Review Quarterly Report January - March 2012. Volume 130

    SciTech Connect

    Shvydky, Alex

    2012-03-01

    This volume of the LLE Review, covering January–March 2012, features “OMEGA Polar-Drive Target Designs,” by P. B. Radha, J. A. Marozas, F. J. Marshall, A. Shvydky, T. J. B. Collins, V. N. Goncharov, R. L. McCrory, P. W. McKenty, D. D. Meyerhofer, T. C. Sangster, and S. Skupsky. This article (p. 57) describes low-adiabat, cryogenic-deuterium–tritium, and warm-plastic-shell polar-drive (PD)–implosion designs for the OMEGA laser. The designs are at two different on-target laser intensities, each at a different in-flight aspect ratio (IFAR). The first design permits one to study implosion energetics and target performance closer to ignition-relevant intensities (7 X 1014 W/cm2 at the quarter-critical surface), where nonlocal heat conduction and laser–plasma interactions can play an important role, but at lower values of IFAR (~22). The second design permits one to study implosion energetics and target performance at a lower intensity (3 X 1014 W/cm2) but at higher IFAR (~32), where the shell instability can play an important role. The higher IFAR designs are accessible on the existing OMEGA Laser System only at lower intensities. Implosions at ignition-relevant intensities can be obtained only by reducing target radius, although only at smaller values of IFAR. Polar-drive geometry requires repointing the laser beams to improve shell symmetry. The higher-intensity designs optimize target performance by repointing beams to a lesser extent and compensate for the reduced equatorial drive by increasing beam energies for the repointed beams and using custom beam profiles that improve equatorial illumination at the expense of irradiation at higher latitudes. These designs will be studied when new phase plates for the OMEGA Laser System, corresponding to the smaller target radii and custom beam profiles, are obtained. Implosion results from the combined set of high-intensity and high-IFAR implosions should yield valuable

  7. LLE Review Quarterly Report. Volume 79, April-June 1999 [Laboratory for Laser Energetics

    SciTech Connect

    1999-04-01

    This volume of the Laboratory for Laser Energetics (LLE) Review, covering the period April-June 1999, features a theoretical analysis of direct-drive target performance on National Ignition Facility (NIF). In this article R. P. J. Town, J. A. Delettrez, R. Epstein, V. N. Goncharov, R. L. McCrory, P. W. McKenty, R. W. Short, and S. Skupsky detail ignition target designs developed at LLE specifically to achieve successful direct-drive ignition on the NIF facility. A baseline ''all-DT'' target design is described along with a two shock compression analysis, which includes discussion of the parameters leading to variability in shock timing. The modeling and analysis presented flow down to specification requirements for the laser and target parameters to ignite this baseline target design with the NIF laser.

  8. LLE (Laboratory for Laser Energetics) review: Quarterly report, January-March 1988

    SciTech Connect

    Kelly, J.

    1988-01-01

    This volume of the LLE Review, covering the period January-March 1988, contains articles on the spectra of scattered laser radiation from laser-produced plasmas and on the bounce coating of ablation layers on fusion targets. The advanced technology section has reports on a novel technique for characterizing surface breakdown on semiconductor devices and on a versatile alexandrite regenerative amplifier. Finally, the activities of the National Laser Users. Facility and the GDL and OMEGA laser facilities are summarized. 49 refs., 30 figs.

  9. LLE experimental data, thermodynamic modeling and sensitivity analysis in the ethyl biodiesel from macauba pulp oil settling step.

    PubMed

    Basso, Rodrigo Corrêa; da Silva, César Augusto Sodré; Sousa, Camila de Oliveira; Meirelles, Antonio José de Almeida; Batista, Eduardo Augusto Caldas

    2013-03-01

    The aim of this study was to obtain experimental data related to liquid–liquid equilibrium (LLE) of systems containing glycerol + ethanol + ethyl biodiesel from macauba pulp oil, perform thermodynamic modeling and simulate the settling step of this biodiesel using simulation software. Binary interaction parameters were adjusted for NRTL and UNIQUAC models. The UNIFAC-LLE and UNIFAC-Dortmund models were used to predict the LLE of the systems. A sensitivity analysis was applied to the settling step to describe the composition of the output streams as a function of ethanol in the feed stream. Ethanol had greater affinity for the glycerol-rich phase. The deviations between experimental data and calculated values were 0.44%, 1.07%, 3.52% and 2.82%, respectively, using the NRTL, UNIQUAC, UNIFAC-LLE and UNIFAC-Dortmund models. Excess ethanol in the feed stream causes losses of ethyl ester in the glycerol-rich stream and high concentration of glycerol in the ester-rich stream. PMID:23384780

  10. LLE 1998 annual report, October 1997--September 1998. Inertial fusion program and National Laser Users` Facility program

    SciTech Connect

    1999-01-01

    This report summarizes research at the Laboratory for Laser Energetics (LLE), the operation of the National Laser Users` Facility (NLUF), and programs involving the education of high school, undergraduate, and graduate students for FY98. Research summaries cover: progress in laser fusion; diagnostic development; laser and optical technology; and advanced technology for laser targets.

  11. Children's Literature as Tools of and for Activism: Reflections of JoLLE's inaugural Activist Literacies Conference

    ERIC Educational Resources Information Center

    Graff, Jennifer M.

    2013-01-01

    Inspired by her attendance at the inaugural JoLLE Activist Literacies conference, the author ruminates on the ways in which children's literature and activitist literacies are inextricably wed and manifested in myriad ways. References to a sampling of children's literature spanning genres and grade levels, websites, and affiliated articles provide…

  12. LLE Quarterly Report (July-September 1999)[Library for Laser Energetics

    SciTech Connect

    2000-01-07

    This volume of the LLE Review, covering the period July-September 1999, features a theoretical analysis of a process that generates mass perturbations of an imploding target driven by modulated laser illumination. The process, referred to as laser imprint, impacts the integrity of the shell during direct-drive implosions, potentially quenching target performance. In this article V. N. Goncharov, J. A. Delettrez, S. Skupsky, and R. P. J. Town present a model of the generation of mass perturbations and analyze the mass perturbation growth due to nonuniform ablation pressure. Stabilizing mechanisms of thermal conduction smoothing and mass ablation are shown to suppress the acceleration perturbation, and mass ablation is also shown to impact velocity perturbations. The model predicts that a direct-drive cryogenic NIF target will remain intact during the implosion when l-Thz SSD beam smoothing is used.

  13. Variable Spaced Grating (VSG) Snout, Rotator and Rails for use at LLE

    SciTech Connect

    Mukherjee, S K; Emig, J A; Griffith, L V; Heeter, R F; House, F A; James, D L; Schneider, M B; Sorce, C M

    2010-01-25

    The Variable Spaced Grating (VSG) is a spectrometer snout mounted to an X-Ray Framing Camera (XRFC) through the Unimount flange. This equipment already exists and is used at the University of Rochester, Laboratory for Laser Energetics (LLE) facility. The XRFC and the Unimount flange are designed by LLE. The Tilt Rotator fixture that mounts next to the XRFC and the cart rails are designed by LLNL, and are included in this safety note. The other related components, such as the TIM rails and the Unimount flange, are addressed in a separate safety note, EDSN09-500005-AA. The Multipurpose Spectrometer (MSPEC) and VSG are mounted on the TIM Boat through the cart rails that are very similar in design. The tilt rotator combination with the Unimount flange is also a standard mounting procedure. The later mounting system has been included in this safety note. Figure-1 shows the interface components and the VSG snout. Figure-2 shows the VSG assembly mounted on the Unimount flange. The calibration pointer attachment is shown in place of the snout. There are two types of VSG, one made of 6061-T6 aluminum, weighing approximately 3 pounds, and the other made of 304 stainless steel, weighing approximately 5.5 pounds. This safety note examines the VSG steel design. Specific experiments may require orienting the VSG snout in 90 degrees increment with respect to the Unimount flange. This is done by changing the bolts position on the VSG-main body adapter flange to the Unimount adapter plate. There is no hazard involved in handling the VSG during this procedure as it is done outside the target chamber on the cart rail before installing on the TIM. This safety note addresses the mechanical integrity of the VSG structure, the tilt rotating fixture, the cart rails with handle and their connections. Safety Factors are also calculated for the MSPEC in place of the VSG.

  14. LLE (Laboratory for Laser Energetics) Review: Quarterly report, January--March 1997. Volume 70

    SciTech Connect

    1997-06-01

    This volume of the LLE Review includes an article on the status of the optics on the OMEGA laser system after the first 18 months of operation. A vigorous program to monitor the performance of the optics has been followed since the inception of the OMEGA laser. The article presents results from these observations and defines the various types of possible damage. Many of the optics have not damaged, such as the frequency-conversion crystals, polarizers, calorimeters, and liquid crystal optics. The most significant damage has been sustained by the fused-silica spatial filter lenses. There has been no evidence of any propagation of damage downstream of damage optics. Other highlights of research presented here are: The development of a single-beam, ponderomotive optical trap for energetic free electrons. A description of the new diode-pumped Nd:YLF master oscillator for the OMEGA laser. Simulations of heat transfer from localized absorbing defects to the host coating material in HfO{sub 2}/SiO{sub 2} 351-nm high reflectors. An experimental study of target performance and mixing in titanium-doped target implosions on OMEGA. A theoretical calculation of the dephasing time of an electron accelerated by a laser pulse. Separate abstracts have been indexed into the energy database from articles in this volume.

  15. Cross-examination of liquid-liquid extraction (LLE) and solid-phase microextraction (SPME) methods for impurity profiling of methamphetamine.

    PubMed

    Lee, Jaesin; Park, Yonghoon; Yang, Wonkyung; Chung, Heesun; Choi, Wonjun; Inoue, Hiroyuki; Kuwayama, Kenji; Park, Jeonghill

    2012-02-10

    Impurities in 48 methamphetamine (MA) samples were analyzed by liquid-liquid extraction (LLE) and headspace solid-phase microextraction (HS-SPME) methods. MPS-2 autosampler was used to improve reproducibility of SPME method, and nonadecane (C(19)) diluted with potassium bromide (KBr) powder was used as an internal standard for standardizing retention time. Impurities identified by SPME method showed different patterns compared with LLE method. Non-volatile impurities like methamphetamine dimer were not identified by SPME method, but some volatile impurities like diphenylketone, caprolactam and lots of unknowns were identified only by SPME method. 1-Phenyl-2-propanone (P2P), 1-phenyl-2-propanol and benzylcyanide peaks could be discriminated clearly by SPME method without interference of amphetamine, an artifact originates from MA degradation. Differences in the impurity patterns resulted in different clustering results. When 48 MA samples were classified into 5 LLE and 5 SPME clusters, cross-matching of the clusters resulted in 8 sub-clusters. It shows that combination of the different extraction methods can distinguish the differences which cannot be distinguished by LLE or SPME method alone, and can improve reliability of the profiling results. PMID:21376486

  16. Analytical power of LLE-HPLC-PDA-MS/MS in drug metabolism studies: identification of new nabumetone metabolites.

    PubMed

    Nobilis, Milan; Mikušek, Jiří; Szotáková, Barbora; Jirásko, Robert; Holčapek, Michal; Chamseddin, Chamseddin; Jira, Thomas; Kučera, Radim; Kuneš, Jiří; Pour, Milan

    2013-06-01

    Nabumetone is a non-acidic, nonsteroidal anti-inflammatory prodrug. Following oral administration, the prodrug is converted in the liver to 6-methoxy-2-naphthylacetic acid (6-MNA), which was found to be the principal metabolite responsible for the NSAID effect. The pathway of nabumetone transformation to 6-MNA has not been clarified, with no intermediates between nabumetone and 6-MNA having been identified to date. In this study, a new, as yet unreported phase I metabolite was discovered within the evaluation of nabumetone metabolism by human and rat liver microsomal fractions. Extracts from the biomatrices were subjected to chiral LLE-HPLC-PDA and achiral LLE-UHPLC-MS/MS analyses to elucidate the chemical structure of this metabolite. UHPLC-MS/MS experiments detected the presence of a structure corresponding to elemental composition C15H16O3, which was tentatively assigned as a hydroxylated nabumetone. Identical nabumetone and HO-nabumetone UV spectra obtained from the PDA detector ruled out the presence of the hydroxy group in the aromatic moiety of nabumetone. Hence, the most likely structure of the new metabolite was 4-(6-methoxy-2-naphthyl)-3-hydroxybutan-2-one (3-hydroxy nabumetone). To confirm this structure, the standard of this nabumetone metabolite was synthesized, its spectral (UV, CD, NMR, MS/MS) and retention properties on chiral and achiral chromatographic columns were evaluated and compared with those of the authentic nabumetone metabolite. To elucidate the subsequent biotransformation of 3-hydroxy nabumetone, the compound was used as a substrate in incubation with human and rat liver microsomal fraction. A number of 3-hydroxy nabumetone metabolites (products of conjugation with glucuronic acid, O-desmethylation, carbonyl reduction and their combination) were discovered in the extracts from the incubated microsomes using LLE-HPLC-PDA-MS/MS experiments. On the other hand, when 3-hydroxy nabumetone was incubated with isolated rat hepatocytes, 6-MNA was

  17. Process-scale reversed-phase high-performance liquid chromatography purification of LL-E19020 alpha, a growth promoting antibiotic produced by Streptomyces lydicus ssp. tanzanius.

    PubMed

    Williams, D R; Carter, G T; Pinho, F; Borders, D B

    1989-12-22

    LL-E19020 alpha is a novel antibiotic produced by fermentation of the soil microorganism Streptomyces lydicus ssp. tanzanius. The compound is highly effective in inducing increases in weight gain and feed conversion efficiency in livestock. In order to obtain kilogram quantities of the material for field trials, pilot plant scale fermentations (up to 7500 l) were carried out. The antibiotic was recovered from the fermentation broth by solvent extraction. The resultant crude extract was subjected to reversed-phase (C18) chromatography on a process-scale high-performance liquid chromatography (HPLC) unit. The heart of the instrumentation is the Millipore Kiloprep chromatograph with the standard 12-l cartridge column. The laboratory housing the chromatograph has been specifically designed for this work. Tanks for mobile phase preparation are mounted on load cells for precise measurement of components. In this explosion-proof laboratory, all solvent handling areas are well ventilated and a separate breathing air system is provided for the operators. For the purification of the LL-E19020 antibiotics, the mobile phase consisted of a gradient of acetonitrile in 0.1 M ammonium acetate at pH 4.5. The effluent was monitored by UV absorbance at 325 nm. Fractions were collected across the peaks of interest and these were analyzed by analytical HPLC. The maximum yield of LL-E19020 alpha obtained in a single run was approximately 100 g. The antibiotic was recovered from the mobile phase by extraction with methylene chloride. The methylene chloride phase was concentrated under reduced pressure to yield a gummy residue which was finally freeze-dried from tertiary butanol to yield an off-white solid suitable for blending with various feed components. PMID:2613793

  18. Simultaneous analysis of aflatoxins B1, B2, G1, G2, M1 and ochratoxin A in breast milk by high-performance liquid chromatography/fluorescence after liquid-liquid extraction with low temperature purification (LLE-LTP).

    PubMed

    Andrade, Patricia Diniz; Gomes da Silva, Julyane Laine; Caldas, Eloisa Dutra

    2013-08-23

    The aims of this study were to optimize and validate a methodology for the simultaneous analysis of aflatoxins B1, B2, G1, G2, M1 (AFB1, AFB2, AFG1, AFG2, AFM1) and ochratoxin A (OTA) in breast milk, and to analyze these mycotoxins in samples obtained from human milk banks in the Federal District, Brazil. The optimized analytical method was based on liquid-liquid extraction with low temperature purification (3.25mL of acidified acetonitrile+0.75mL of ethyl acetate), followed by analysis by high-performance liquid chromatography with fluorescence detector (HPLC/FLD) and a photochemical post-column reactor. Limits of quantification (LOQ) ranged from 0.005 to 0.03ng/mL, recoveries from 73 to 99.5%, and relative standard deviations (RSD) from 1.8 to 17.3%. The LLE-LTP extraction method was shown to be simple and cost-effective, since no columns were needed for clean-up. Only 2 of the 224 breast milk samples analyzed were positive for the mycotoxins, both samples containing AFB2 at the LOQ level (0.005ng/mL). The identity of the mycotoxin detected was confirmed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). This result indicates that infants who are fed with breast milk from the milk banks are not at risk from aflatoxin and ochratoxin exposure. PMID:23871563

  19. Unfälle mit Pkw

    NASA Astrophysics Data System (ADS)

    Burg, Heinz

    Der Verkehrsunfall ereignete sich innerorts auf einer Kreuzung mit rechts vor links Regelung. Es galt dort die allgemeine Geschwindigkeitsbegrenzung auf 50 km/h. Zur Unfallzeit war es hell und trocken. Die Fahrbahn hatte eine Schwarzdecke.

  20. LLE Review 119 (April-June 2009)

    SciTech Connect

    Edgell, D.H., editor

    2009-10-22

    This issue has the following articles: (1) Shock-Ignition Experiments on OMEGA at NIF-Relevant Intensities; (2) Laser-Driven Magnetic-Flux Compression in High-Energy-Density Plasmas; (3) Lorentz Mapping of Magnetic Fields in Hot, Dense Plasmas; (4) Characterization and Optimization of Yb-Doped Photonic-Crystal Fiber Rod Amplifiers Using Spatially Resolved Spectral Interferometry; (5) Optical Differentiation and Multimillijoule {approx}150-ps Pulse Generation in a Regenerative Amplifier with a Temperature-Tuned Intracavity Volume Bragg Grating; (6) Slow Crack Growth During Radiatiave Cooling of LHG8 and BK7 Plates; and (7) Finite Element Simulation of Metal-Semiconductor-Metal Photoconductor.

  1. LLE Review 121 (September-December 2009)

    SciTech Connect

    Anderson, K.S., editor

    2010-04-14

    This issue has the following articles: (1) Demonstration of the Highest Deuterium-Tritium Areal Density Using Triple-Picket Cryogenic Designs on OMEGA; (2) High-Precision Measurements of the Equation of State of Hydrocarbons at 1 to 10 Mbar Using Laser-Driven Shock Waves; (3) A Generalized Measurable Ignition Condition for Inertial Confinement Fusion (4) In-Situ Detection and Analysis of Laser-Induced Damage on a 1.5-m Multilayer-Dielectric Grating Compressor for High-Energy, Petawatt-Class Laser Systems; (5) Probing High-Areal-Density ({rho}R) Cryogenic-DT Implosions Using Down-Scattered Neutron Spectra Measured by the Magnetic Recoil Spectrometer; (6) Strong-Coupling and Degeneracy Effects in Inertial Confinement Fusion Implosions; and (7) Neutron-Induced Nucleation Inside Bubble Chambers Using Freon 115 as the Active Medium.

  2. LLE Review 118 (January-March 2009)

    SciTech Connect

    Bittle, W., editor

    2009-08-03

    This issue has the following articles: (1) Applied Plasma Spectroscopy: Laser-Fusion Experiments; (2) Relativistic Electron-Beam Transport Studies Using High-Resolution, Coherent Transition Radiation Imaging; (3) Pressure-Driven, Resistive Magnetohydrodynamic Interchange Instabilities in Laser-Produced, High-Energy-Density Plasmas; (4) Extended Model for Polymer Cholesteric Liquid Crystal Flake Reorientation and Relaxation; (5) Modeling the Effects of Microencapsulation on the Electro-Optic Behavior of Polymer Cholesteric Liquid Crystal Flakes; (6) Capillarity and Dielectrophoresis of Liquid Deuterium; and (7) A Stable Mid-IR, GaSb-Based Diode Laser Source for Cryogenic Target Layering at the OMEGA Laser Facility.

  3. LLE 1994 annual report, October 1993--September 1994

    SciTech Connect

    1995-01-01

    This is the 1994 annual report for the University of Rochester, Laboratory for Laser Energetics. The report is presented as a series of research type reports. The titles emphasize the breadth of work carried out. They are: stability analysis of unsteady ablation fronts; characterization of laser-produced plasma density profiles using grid image refractometry; transport and sound waves in plasmas with light and heavy ions; three-halves-harmonic radiation from long-scale-length plasmas revisited; OMEGA upgrade status report; target imaging and backlighting diagnosis; effect of electron collisions on ion-acoustic waves and heat flow; particle-in-cell code simulations of the interaction of gaussian ultrashort laser pulses with targets of varying initial scale lengths; characterization of thick cryogenic fuel layers: compensation for the lens effect using convergent beam interferometry; compact, multijoule-output, Nd:Glass, large-aperture ring amplifier; atomic force microscopy observation of water-induced morphological changes in Y{sub 2}O{sub 3} monolayer coatings; observation of longitudinal acceleration of electrons born in a high-intensity laser focus; spatial intensity nonuniformities of an OMEGA beam due to nonlinear beam propagation; calculated X-ray backlighting images of mixed imploded targets; evaluation of cosmic rays for use in the monitoring of the MEDUSA scintillator-photomultiplier diagnostic array; highly efficient second-harmonic generation of ultra-intense Nd:Glass laser pulses multiple cutoff wave numbers of the ablative Rayleigh-Taylor instability; ultrafast, all-silicon light modulator; angular dependence of the stimulated Brillouin scattering in homogeneous plasma; femtosecond excited-state dynamics of a conjugated ladder polymer.

  4. LLE Review: Quarterly report, July--September 1994. Volume 60

    SciTech Connect

    Knauer, J.P.

    1994-12-31

    This volume contains articles on efficient generation of second-harmonic radiation from short-pulse lasers; calculation of the stabilization cutoff wave numbers for the Rayleigh-Taylor instability; a high-frequency silicon optical modulator; the angular dependence of stimulated Brillouin scattering; and femtosecond dynamics of ladder polymers. Three of these articles--second-harmonic generation, Rayleigh-Taylor cutoff wave numbers, and angular dependence of Brillouin scattering--are directly related to the OMEGA Upgrade, currently under construction. A summary of the status of the OMEGA Upgrade laser facility and the NLUF News for FY94 are included in this volume.

  5. LLE Review, Volume 57. Quarterly report, October--December 1993

    SciTech Connect

    Simon, A.

    1993-12-31

    During this quarter, the visible fruits of long design labors on the OMEGA Upgrade began to appear. The target mirror structure was put in place, along with the target chamber itself. The laser bay structures were also installed, and the bay is now being prepared to receive optomechanical, control, and laser assemblies. Further details are in the OMEGA Upgrade Status Report in this issue. Theory and analysis of previous experiments continued during this reporting period. Articles contained herein describe an improved theory of the ablative Rayleigh-Taylor instability; a novel proposal for characterizing plasma-density profiles by using grid image refractometry; a much-improved treatment of the damping of ion sound waves in a mixture of light and heavy ions; and, finally, a new interpretation of measurements of 3/2-harmonic radiation emitted from the long-scale-length plasmas created in earlier OMEGA experiments.

  6. LLE review: Quarterly report, April--June 1996. Volume 67

    SciTech Connect

    Skeldon, M.D.

    1996-11-01

    This volume contains articles detailing several nonlinear processes associated with lasers and their use, as well as an article describing the computer control systems necessary to maintain and operate a large laser system such as the 60-beam OMEGA laser. The specific topics discussed in this issue include stimulated scattering in laser plasmas, power exchange between interacting laser beams, charged particles interacting with a laser pulse, thermal equilibration of optically excited states, an overview of the laser control system software in OMEGA, and a technique for cancellation of the nonlinear phase accumulation in short-pulse lasers.

  7. LLE 2005 annual report, October 2004-September 2005

    SciTech Connect

    None, None

    2006-01-01

    Progress in laser fusion this past year falls into five broad categories: (1) direct-drive results from OMEGA; (2) progress in the development of the cryogenic target system and experiments with cryogenic targets; (3) results for polar direct drive (the application of nonspherically disposed laser beams for direct-drive spherically symmetrically driven systems), which is of great interest for the National Ignition Facility (NIF); (4) fast ignition, which uses short-pulse (<100-ps), high-intensity (~1015-W) laser beams to ignite a compressed thermonuclear fusion capsule; and (5) high-energy-density physics results that use inertial fusion facilities to produce matter in extreme states that are central to understanding and modeling nuclear weapons phenomena important to the National Stockpile Stewardship Program.

  8. Unfälle mit motorisierten Zweirädern

    NASA Astrophysics Data System (ADS)

    Tschirschwitz, Christian

    Der Fahrer eines Pkw Opel Astra überquerte mit seinem Pkw von einer untergeordneten Einmündung kommend eine außerörtliche Bundesstraße in gerade Richtung. Dabei kam es zur Kollision mit einem sich von rechts vorfahrtsberechtigt annähernden Krad Suzuki RGV250. Der Anprall des Krades erfolgte mit dem Heck an die rechte Pkw-Flanke zwischen vorderem Radausschnitt und Fahrzeugecke. Der Krad-Fahrer, welcher sofort tot war und das Zweirad verklemmten sich am Pkw und verblieben relativ zu selbigem annähernd in Kollisionsstellung.

  9. LLE review, volume 73. Quarterly report, October 1997--December 1997

    SciTech Connect

    1998-04-01

    This progress report contains discussion on the following topics: A high-bandwidth electrical-waveform generator based on aperture-coupled striplines for OMEGA pulse-shaping applications; sweep deflection circuit development using computer-aided circuit design for the OMEGA multichannel streak camera; D-{sup 3}He protons as a diagnostic for target {rho}R; growth rates of the ablative Rayleigh-Taylor instability in inertial confinement fusion; three-dimensional analysis of the power transfer between crossed laser beams; characterization of freestanding polymer films for application in 351-nm, high-peak-power laser systems; subsurface damage in microgrinding optical glasses; bound-abrasive polishers for optical glass; and color gamut of cholesteric liquid crystal films and flakes by standard colorimetry.

  10. Effectiveness of Program Visualization: A Case Study with the ViLLE Tool

    ERIC Educational Resources Information Center

    Rajala, Teemu; Laakso, Mikko-Jussi; Kaila, Erkki; Salakoski, Tapio

    2008-01-01

    Program visualization is one of the various methods developed over the years to aid novices with their difficulties in learning to program. It consists of different graphical--often animated--and textual objects, visualizing the execution of programs. The aim of program visualization is to enhance students' understanding of different areas of…

  11. LLNL Contribution to LLE FY09 Annual Report: NIC and HED Results

    SciTech Connect

    Heeter, R F; Landen, O L; Hsing, W W; Fournier, K B

    2009-10-01

    In FY09, LLNL led 238 target shots on the OMEGA Laser System. Approximately half of these LLNL-led shots supported the National Ignition Campaign (NIC). The remainder was dedicated to experiments for the high-energy-density stewardship experiments (HEDSE). Objectives of the LLNL led NIC campaigns at OMEGA included: (1) Laser-plasma interaction studies in physical conditions relevant for the NIF ignition targets; (2) Demonstration of Tr = 100 eV foot symmetry tuning using a reemission sphere; (3) X-ray scattering in support of conductivity measurements of solid density Be plasmas; (4) Experiments to study the physical properties (thermal conductivity) of shocked fusion fuels; (5) High-resolution measurements of velocity nonuniformities created by microscopic perturbations in NIF ablator materials; (6) Development of a novel Compton Radiography diagnostic platform for ICF experiments; and (7) Precision validation of the equation of state for quartz. The LLNL HEDSE campaigns included the following experiments: (1) Quasi-isentropic (ICE) drive used to study material properties such as strength, equation of state, phase, and phase-transition kinetics under high pressure; (2) Development of a high-energy backlighter for radiography in support of material strength experiments using Omega EP and the joint OMEGA-OMEGA-EP configuration; (3) Debris characterization from long-duration, point-apertured, point-projection x-ray backlighters for NIF radiation transport experiments; (4) Demonstration of ultrafast temperature and density measurements with x-ray Thomson scattering from short-pulse laser-heated matter; (5) The development of an experimental platform to study nonlocal thermodynamic equilibrium (NLTE) physics using direct-drive implosions; (6) Opacity studies of high-temperature plasmas under LTE conditions; and (7) Characterization of copper (Cu) foams for HEDSE experiments.

  12. Arsenic-related skin lesions and glutathione S-transferase P1 A1578G (lle105Val) polymorphism in two ethnic clans exposed to indoor combustion of high arsenic coal in one village

    SciTech Connect

    Lin, G.F.; Du, H.; Chen, J.G.; Lu, H.C.; Guo, W.C.; Meng, H.; Zhang, T.B.; Zhang, X.J.; Lu, D.R.; Golka, K.; Shen, J.H.

    2006-12-15

    A total of 2402 patients with arsenic-related skin lesions, such as hyperkeratosis, hyperpigmentation or hypopigmentation, or even skin cancer in a few villages in Southwest Guizhou Autonomous Prefecture, China represent a unique case of endemic arsenism related with indoor combustion of high arsenic coal. This study aimed to investigate the cluster of arsenism cases and the possible relevant factors including GSTP1 polymorphism in two clans of different ethnic origin living in one village for generations. Arsenism morbidity in Miao clan P was significantly lower than in the neighbouring Han clan G1 (5.9 vs. 32.7%, odds ratio (OR)=0.13, 95% confidence interval (CI): 0.06-0.27, P < 0.0001). No sex differences were confirmed inside both clans. Analyses of the environmental samples indicated that Miao clan P members were exposed to higher amounts of arsenic via inhalation and food ingestion. Hair and urine samples also proved a higher arsenic body burden in ethnic Miao individuals. No corresponding differences by sex were found. Higher frequencies of combined mutant genotype G/G1578 and A/G1578 (OR=4.72, 95% CI: 2.34-9.54, P < 0.0001) and of mutant allele G1578 (OR=3.22, 95% CI: 2.00-5.18, P < 0.0001) were detected in diagnosed arsenism patients than in non-diseased individuals. The Miao individuals showed a lower percentage of combined mutant genotypes (30.6 vs. 52.7%, OR=0.40, 95% CI: 0.19-0.84, P=0.015) as well as of mutant allele G1578 (OR=0.46, 95% CI: 0.24-0.88, P=0.017) than their Han neighbours. Conclusions Genetic predisposition influences dermal arsenism toxicity. The GSTP1 A1578G (IIe105Val) status might be a susceptibility factor for arsenic-related skin lesions.

  13. A Pilot Study Using the Gynecologic Cancer Lymphedema Questionnaire (GCLQ) as a Clinical Care Tool to Identify Lower Extremity Lymphedema in Gynecologic Cancer Survivors

    PubMed Central

    Carter, Jeanne; Raviv, Leigh; Appollo, Kathleen; Baser, Raymond E.; Iasonos, Alexia; Barakat, Richard R.

    2016-01-01

    Objective To determine the feasibility and efficacy of using the Gynecologic Cancer Lymphedema Questionnaire (GCLQ) as a symptom scale for lymphedema of the lower extremity (LLE). Methods Twenty-eight gynecologic cancer survivors with documented LLE and 30 without a history or presence of lymphedema completed the GCLQ and provided feedback about their satisfaction with and feasibility of using the GCLQ at their oncology follow-ups. The study survey took approximately 5–10 minutes to complete, and it was easily understood by the majority of the sample. Results Participants had a mean age of 59.6 years (range, 28–80 years). Twenty-eight women (48%) had LLE and 30 (52%) had no history or presence of LLE (confirmed by limb volume [LV] measurements at assessment). Type of cancer history included: endometrial, 38 (66%); cervical, 13 (22%); and vulvar, 7 (12%). GCLQ scores differed significantly by lymphedema diagnosis; LLE patients had higher scores (P<0.01). The large area under the curve (AUC) of 0.95 (95% CI: 0.90–1.000) suggests that the GCLQ can distinguish between patients with and without LLE. Although all 28 (100%) of the LLE patients were aware of their LLE diagnosis, only 23 (82%) underwent treatment. The GCLQ was easily understood by most (55/58, 95%); and overall, patients showed a high willingness (56/58, 96%) to complete the questionnaire at future appointments. Twenty-five (88%) of the LLE patients found the GCLQ to be helpful in identifying symptoms of lymphedema. Conclusions The GCLQ effectively distinguished between gynecologic cancer survivors with and those without LLE, with good sensitivity and specificity. The patients, particularly those with LLE, showed high confidence in the GCLQ’s ability to detect LLE symptoms. PMID:20163847

  14. Computing Liquid-Liquid Phase Equilibria: An Exercise for Understanding the Nature of False Solutions and How to Avoid Them

    ERIC Educational Resources Information Center

    Olaya, Maria del Mar; Ibarra, Isabel; Reyes-Labarta, Juan A.; Serrano, Maria Dolores; Marcilla, Antonio

    2007-01-01

    An exercise to compute LLE data is presented to illustrate the problems that can arise when the isoactivity equilibrium condition is used in the LLE calculations. A much more efficient condition is obtained when isoactivity is combined with the common tangent line criterion, avoiding false solutions that correspond with very low values of the…

  15. Becoming an L2 Learner (Again): How a Brief Language Learning Experience Sparked Connections with SLA Theory

    ERIC Educational Resources Information Center

    Forman, Ross

    2015-01-01

    A brief "language learning experience" (LLE) in Thai was integrated into a second language development course as part of postgraduate TESOL study at an Australian university. Sixty primary and secondary teachers from a range of schools evaluated the impact of the LLE by means of a questionnaire; the teachers proved highly affirming of…

  16. The Relations between the Mental Condition of the Care House Residents and Finger Plethysmograms

    NASA Astrophysics Data System (ADS)

    Hirohashi, Yoko; Oyama-Higa, Mayumi; Lee, Sangjae

    2011-06-01

    We measured the fingertip pulse waves of some of the elderly living in a care house (a welfare facility for the elderly) four times a day over two days to investigate their mental condition. We analyzed the chaotic information produced by the finger pulse waves using a nonlinear analysis method. The results of our research are as follows: 1) The Largest Lyapunov Exponent (LLE), which synchronizes to mental revitalization, rose when the care house residents felt happy. 2) After moderate movement (a stroll, etc.), the LLE was high. 3) The LLE did not rise when a regular action was carried out non-vigorously to kill time. 4) When residents made contact (a phone call or letter, etc.) with a family member, the LLE was high. 5) The LLE of long-term residents was high. 6) The majority of residents with high LLE moved into the care house in their early seventies. 7) The LLE of short-term residents was low and their sympathetic nerves were high. 8) There was no relativity between the LLE and present age of the care house residents. On this basis, the authors propose that fuller support of care house residents is crucial for the objective ascertainment of their mental condition.

  17. Narrative Skill and Syntactic Complexity in School-Age Children with and without Late Language Emergence

    ERIC Educational Resources Information Center

    Domsch, Celeste; Richels, Corrin; Saldana, Michelle; Coleman, Cardin; Wimberly, Clayton; Maxwell, Lauren

    2012-01-01

    Background: Children who do not produce single words by the expected age have been described as "late talkers" or as demonstrating "late language emergence" (LLE). Although their short-term growth in vocabulary is often strong, longer-term consequences of LLE remain in dispute. It has been argued that the majority of school-age children who had…

  18. High-Energy Petawatt Capability for the Omega Laser

    SciTech Connect

    Waxer, L.J.; Maywar, D.N.; Kelly, J.H.; Kessler, T.J.; Kruschwitz, B.E.; Loucks, S.J.; McCrory, R.L.; Meyerhofer, D.D.; Morse, S.F.B.; Stoeckl, C.; Zuegel, J.D.

    2005-07-25

    The 60-beam Omega laser system at the University of Rochester's Laboratory for Laser Energetics (LLE) has been a workhorse on the frontier of laser fusion and high-energy-density physics for more than a decade. LLE scientists are currently extending the performance of this unique, direct-drive laser system by adding high-energy petawatt capabilities.

  19. Principles of Stagewise Separation Process Calculations: A Simple Algebraic Approach Using Solvent Extraction.

    ERIC Educational Resources Information Center

    Crittenden, Barry D.

    1991-01-01

    A simple liquid-liquid equilibrium (LLE) system involving a constant partition coefficient based on solute ratios is used to develop an algebraic understanding of multistage contacting in a first-year separation processes course. This algebraic approach to the LLE system is shown to be operable for the introduction of graphical techniques…

  20. Light Lithophile Elements in Natural and Experimental Phases in Martian Basalts: Implications for the Degassing of Water from Martian Magmas

    NASA Technical Reports Server (NTRS)

    Herd, C. D. K.; Treiman, A. H.; McKay, G. A.; Shearer, C. K.

    2003-01-01

    Lentz et al. argued that zoning trends in light lithophile elements (LLE) in pyroxene in Shergotty and Zagami are evidence for the degassing of magmatic water. We tested this inference by obtaining: additional LLE analyses of Shergotty and Zagami pyroxene; analyses of Pasamonte pyroxene; and silicate and phosphate partition coefficients for B and Li for martian magma and mineral compositions.

  1. Estimating the largest Lyapunov exponent and noise level from chaotic time series.

    PubMed

    Yao, Tian-Liang; Liu, Hai-Feng; Xu, Jian-Liang; Li, Wei-Feng

    2012-09-01

    A novel method for estimating simultaneously the largest Lyapunov exponent (LLE) and noise level (NL) from a noisy chaotic time series is presented in this paper. We research the influence of noise on the average distance of different pairs of points in an embedding phase space and provide a rescaled formula for calculating the LLE when the time series is contaminated with noise. Our algorithm is proposed based on this formula and the invariant of the LLE in different dimensional embedding phase spaces. With numerical simulation, we find that the proposed method provides a reasonable estimate of the LLE and NL when the NL is less than 10% of the signal content. The comparison with Kantz algorithm shows that our method gives more accurate results of the LLE for the noisy time series. Furthermore, our method is not sensitive to the distribution of the noise. PMID:23020441

  2. REDUCING THE DIMENSIONALITY OF DATA: LOCALLY LINEAR EMBEDDING OF SLOAN GALAXY SPECTRA

    SciTech Connect

    Vanderplas, Jake; Connolly, Andrew

    2009-11-15

    We introduce locally linear embedding (LLE) to the astronomical community as a new classification technique, using Sloan Digital Sky Survey spectra as an example data set. LLE is a nonlinear dimensionality reduction technique that has been studied in the context of computer perception. We compare the performance of LLE to well-known spectral classification techniques, e.g., principal component analysis and line-ratio diagnostics. We find that LLE combines the strengths of both methods in a single, coherent technique, and leads to improved classification of emission-line spectra at a relatively small computational cost. We also present a data subsampling technique that preserves local information content, and proves effective for creating small, efficient training samples from large, high-dimensional data sets. Software used in this LLE-based classification is made available.

  3. Partitioning of light lithophile elements during basalt eruptions on Earth and application to Martian shergottites

    NASA Astrophysics Data System (ADS)

    Edmonds, Marie

    2015-02-01

    An enigmatic record of light lithophile element (LLE) zoning in pyroxenes in basaltic shergottite meteorites, whereby LLE concentrations decrease dramatically from the cores to the rims, has been interpreted as being due to partitioning of LLE into a hydrous vapor during magma ascent to the surface on Mars. These trends are used as evidence that Martian basaltic melts are water-rich (McSween et al., 2001). Lithium and boron are light lithophile elements (LLE) that partition into volcanic minerals and into vapor from silicate melts, making them potential tracers of degassing processes during magma ascent to the surface of Earth and of other planets. While LLE degassing behavior is relatively well understood for silica-rich melts, where water and LLE concentrations are relatively high, very little data exists for LLE abundance, heterogeneity and degassing in basaltic melts. The lack of data hampers interpretation of the trends in the shergottite meteorites. Through a geochemical study of LLE, volatile and trace elements in olivine-hosted melt inclusions from Kilauea Volcano, Hawaii, it can be demonstrated that lithium behaves similarly to the light to middle rare Earth elements during melting, magma mixing and fractionation. Considerable heterogeneity in lithium and boron is inherited from mantle-derived primary melts, which is dominant over the fractionation and degassing signal. Lithium and boron are only very weakly volatile in basaltic melt erupted from Kilauea Volcano, with vapor-melt partition coefficients <0.1. Degassing of LLE is further inhibited at high temperatures. Pyroxene and associated melt inclusion LLE concentrations from a range of volcanoes are used to quantify lithium pyroxene-melt partition coefficients, which correlate negatively with melt H2O content, ranging from 0.13 at low water contents to <0.08 at H2O contents >4 wt%. The observed terrestrial LLE partitioning behavior is extrapolated to Martian primitive melts through modeling. The zoning

  4. Monte Carlo modelling of the low-loss electron signal in scanning electron microscopy and comparison with the BSE signal

    NASA Astrophysics Data System (ADS)

    Bonet, C.; El-Gomati, M. M.; Matthew, J. A. D.; Tear, S. P.

    2010-02-01

    Nanotechnology places increasing demands on techniques for sample characterisation on the sub-100 nm length scale, and the low-loss electron (LLE) signal may provide one possible way of addressing this need. Simulations of the LLE signal from a line-scan across a semiconductor superlattice structure have been performed using two different Monte Carlo models in order to assess their effectiveness in predicting spatial resolution for compositional imaging. Additionally, experimental measurements of LLE data using a detector added to a scanning electron microscope were made to investigate compositional contrast.

  5. Event-shape of dileptons plus missing energy at a linear collider as a supersymmetry/Arkani-Hamed-Dimopoulos-Dvali discriminant

    NASA Astrophysics Data System (ADS)

    Roy, Probir

    2007-11-01

    An event-shape analysis of the dileptons in the process e+e- → l+l-E, studied in ILC or CLIC, can clearly discriminate between a supersymmetric or a large extra dimensional (ADD) production mechanism.

  6. Evaluation of Risk for Late Language Emergence after In Utero Antiretroviral Drug Exposure in HIV-exposed Uninfected Infants

    PubMed Central

    Rice, Mabel L.; Zeldow, Bret; Siberry, George K.; Purswani, Murli; Malee, Kathleen; Hoffman, Howard J.; Frederick, Toni; Buchanan, Ashley; Sirois, Patricia A.; Allison, Susannah M.; Williams, Paige L

    2013-01-01

    Background Combination antiretroviral (cARV) regimens are recommended for pregnant women with HIV to prevent perinatal HIV transmission. Safety is a concern for infants who were HIV-exposed but uninfected (HEU), particularly for neurodevelopmental problems, such as language delays. Methods We studied late language emergence (LLE) in HEU children enrolled in a US-based prospective cohort study. LLE was defined as a caregiver-reported score ≤ 10th percentile in any of 4 domains of the MacArthur-Bates Communicative Development Inventory for one-year-olds and as ≥1 standard deviation below age-specific norms for the Ages and Stages Questionnaire for two-year-olds. Logistic regression models were used to evaluate associations of in utero cARV exposure with LLE, adjusting for infant, maternal, and environmental characteristics. Results 1,129 language assessments were conducted among 792 one- and two-year-olds (50% male, 62% black, and 37% Hispanic). Overall, 86% had in utero exposure to cARV and 83% to protease inhibitors. LLE was identified in 26% of one-year-olds and 23% of two-year-olds, with higher rates among boys. In adjusted models, LLE was not associated with maternal cARV or ARV drug classes in either age group. Among cARV-exposed one-year-olds, increased odds of LLE was observed for those exposed to atazanavir (aOR=1.83, 95% CI=1.10-3.04), particularly after the first trimester (aOR=3.56, p=0.001), compared to atazanavir-unexposed infants. No associations of individual ARV drugs with LLE were observed among two-year-olds. Conclusions In utero cARV exposure showed little association with LLE, except for a higher risk of language delay observed in one-year-old infants with atazanavir exposure. PMID:24067563

  7. [Diverse sustainability--sustainable diversity].

    PubMed

    Schmeling-Kludas, Christoph; Koch-Gromus, Uwe

    2011-08-01

    In spite of its plenitude, the scientific works of the important German psychologist Ernst August Dölle (1898-1972) are little adapted till today, mostly they are being reduced to his studies about dichotomy and duplicity. But based on his diaries of the year 1968, the authors can verify without doubt, that Dölle far ahead of his time, carried on research about sustainability and diversity. He was the first scientist worldwide to connect these two concepts. PMID:21837611

  8. Thiolene and SIFEL-based Microfluidic Platforms for Liquid-Liquid Extraction

    PubMed Central

    Goyal, Sachit; Desai, Amit V.; Lewis, Robert W.; Ranganathan, David R.; Li, Hairong; Zeng, Dexing; Reichert, David E.; Kenis, Paul J.A.

    2014-01-01

    Microfluidic platforms provide several advantages for liquid-liquid extraction (LLE) processes over conventional methods, for example with respect to lower consumption of solvents and enhanced extraction efficiencies due to the inherent shorter diffusional distances. Here, we report the development of polymer-based parallel-flow microfluidic platforms for LLE. To date, parallel-flow microfluidic platforms have predominantly been made out of silicon or glass due to their compatibility with most organic solvents used for LLE. Fabrication of silicon and glass-based LLE platforms typically requires extensive use of photolithography, plasma or laser-based etching, high temperature (anodic) bonding, and/or wet etching with KOH or HF solutions. In contrast, polymeric microfluidic platforms can be fabricated using less involved processes, typically photolithography in combination with replica molding, hot embossing, and/or bonding at much lower temperatures. Here we report the fabrication and testing of microfluidic LLE platforms comprised of thiolene or a perfluoropolyether-based material, SIFEL, where the choice of materials was mainly guided by the need for solvent compatibility and fabrication amenability. Suitable designs for polymer-based LLE platforms that maximize extraction efficiencies within the constraints of the fabrication methods and feasible operational conditions were obtained using analytical modeling. To optimize the performance of the polymer-based LLE platforms, we systematically studied the effect of surface functionalization and of microstructures on the stability of the liquid-liquid interface and on the ability to separate the phases. As demonstrative examples, we report (i) a thiolene-based platform to determine the lipophilicity of caffeine, and (ii) a SIFEL-based platform to extract radioactive copper from an acidic aqueous solution. PMID:25246730

  9. Thiolene and SIFEL-based Microfluidic Platforms for Liquid-Liquid Extraction.

    PubMed

    Goyal, Sachit; Desai, Amit V; Lewis, Robert W; Ranganathan, David R; Li, Hairong; Zeng, Dexing; Reichert, David E; Kenis, Paul J A

    2014-01-01

    Microfluidic platforms provide several advantages for liquid-liquid extraction (LLE) processes over conventional methods, for example with respect to lower consumption of solvents and enhanced extraction efficiencies due to the inherent shorter diffusional distances. Here, we report the development of polymer-based parallel-flow microfluidic platforms for LLE. To date, parallel-flow microfluidic platforms have predominantly been made out of silicon or glass due to their compatibility with most organic solvents used for LLE. Fabrication of silicon and glass-based LLE platforms typically requires extensive use of photolithography, plasma or laser-based etching, high temperature (anodic) bonding, and/or wet etching with KOH or HF solutions. In contrast, polymeric microfluidic platforms can be fabricated using less involved processes, typically photolithography in combination with replica molding, hot embossing, and/or bonding at much lower temperatures. Here we report the fabrication and testing of microfluidic LLE platforms comprised of thiolene or a perfluoropolyether-based material, SIFEL, where the choice of materials was mainly guided by the need for solvent compatibility and fabrication amenability. Suitable designs for polymer-based LLE platforms that maximize extraction efficiencies within the constraints of the fabrication methods and feasible operational conditions were obtained using analytical modeling. To optimize the performance of the polymer-based LLE platforms, we systematically studied the effect of surface functionalization and of microstructures on the stability of the liquid-liquid interface and on the ability to separate the phases. As demonstrative examples, we report (i) a thiolene-based platform to determine the lipophilicity of caffeine, and (ii) a SIFEL-based platform to extract radioactive copper from an acidic aqueous solution. PMID:25246730

  10. Preventive effects of lignan extract from flax hulls on experimentally induced benign prostate hyperplasia.

    PubMed

    Bisson, Jean-François; Hidalgo, Sophie; Simons, Rudy; Verbruggen, Marian

    2014-06-01

    Consumption of diet rich in lignans may decrease the risk of some chronic hormonal conditions such as benign prostatic hyperplasia (BPH). This study investigated whether a lignan-rich extract from flaxseed hulls, LinumLife EXTRA (LLE), could prevent BPH using the testosterone propionate (TP)-induced BPH rat model. Male Wistar-Unilever rats were randomly divided into four groups of 12 rats each: a negative control group fed with control diet and receiving daily subcutaneous injections of corn oil without TP, and three groups fed with control diet (positive control), diet containing 0.5% LLE (LLE 0.5) or 1.0% LLE (LLE 1.0) and receiving daily subcutaneous injections of TP in corn oil. Treatments with diets started 2 weeks before the induction of BPH and were carried out for 5 consecutive weeks. The influence of TP and LLE on body weight (BW), food and water consumptions, and enterolactone (ENL) levels in serum and urine of rats was examined at the end of the 5-week treatment period. TP significantly diminished the mean body weight gain (MBWG) of positive control rats and their food and water consumptions while LLE reduced significantly this MBWG reduction in a dose-dependent manner. The lignan-rich extract significantly inhibited TP-induced prostate size ratio (prostate weight/rat BW) increase in comparison with positive controls (P<.001). This effect was dose dependent. Higher serum and urine levels of ENL correlated well with the dose of extract provided to rats. It was concluded that the lignan-rich flaxseed hull extract prevented the TP-induced BPH indicating it might be beneficial in the prevention of BPH. PMID:24460407

  11. 1999 Summer Research Program for High School Juniors at the University of Rochester's Laboratory for Laser Energetics

    SciTech Connect

    2002-10-09

    oak-B202--During the summer of 1999, 12 students from Rochester-area high schools participated in the Laboratory for Laser Energetics' Summer High School Research Program. The goal of this program is to excite a group of high school students about careers in the areas of science and technology by exposing them to research in a state-of-the-art environment. Too often, students are exposed to ''research'' only through classroom laboratories that have prescribed procedures and predictable results. In LLE's summer program, the students experience all of the trials, tribulations, and rewards of scientific research. By participating in research in a real environment, the students often become more enthusiastic about careers in science and technology. In addition, LLE gains from the contributions of the many highly talented students who are attracted to the program. The students spent most of their time working on their individual research projects with members of LLE's technical staff. The projects were related to current research activities at LLE and covered a broad range of areas of interest including laser modeling, diagnostic development, chemistry, liquid crystal devices, and opacity data visualization. The students, their high schools, their LLE supervisors and their project titles are listed in the table. Their written reports are collected in this volume. The students attended weekly seminars on technical topics associated with LLE's research. Topics this year included lasers, fusion, holography, optical materials, global warming, measurement errors, and scientific ethics. The students also received safety training, learned how to give scientific presentations, and were introduced to LLE's resources, especially the computational facilities. The program culminated with the High School Student Summer Research Symposium on 25 August at which the students presented the results of their research to an audience that included parents, teachers, and members of LIX. Each

  12. A Study of Care Work in Welfare Facilities for the Elderly, Using Non Linear Analysis of Finger Plethysmograms

    NASA Astrophysics Data System (ADS)

    Hirohashi, Yoko; Oyama-Higa, Mayumi; Lee, Sangjae

    2011-06-01

    The fingertip pulse waves of a number of staff working in a daycare center for the elderly and a special nursing home for the elderly were measured several times throughout the day for a period of one or two days, and the chaotic information gained was analyzed using a non linear analysis method. As a result, a relation between the staff's length of career and the change of Largest Lyapunov Exponent (LLE) of the fingertip pulse waves that synchronized with the mental revitalization degrees and the tension of the sympathetic nerve was evident. The LLE of the staff with short careers dramatically changed and also took a long time to settle down again. In addition, staff LLE changed greatly after sessions of bathing assistance and watching residents with dementia. LLE measurements showed drops in some staff after a period of rest, but this was not the case for other staff. It can be concluded that the LLE is related to the length of the staff member's career and what is actually done during working hours and rest periods. A high level of sympathetic nerve was seen in almost all of the care workers. On this basis, the authors propose that improvements are needed in the content of the care work.

  13. Liquid-Liquid Extraction and Solid Phase Extraction for Urinary Organic Acids: A Comparative Study from a Resource Constraint Setting.

    PubMed

    Kumari, Chandrawati; Varughese, Bijo; Ramji, Siddarth; Kapoor, Seema

    2016-10-01

    Pre analytical process of extraction for accurate detection of organic acids is a crucial step in diagnosis of organic acidemias by GCMS analysis. This process is accomplished either by solid phase extraction (SPE) or by liquid-liquid extraction (LLE). Both extraction procedures are used in different metabolic laboratories all over the world. In this study we compared these two extraction procedures in respect of precision, accuracy, percent recovery of metabolites, number of metabolites isolated, time and cost in a resource constraint setup. We observed that the mean recovery from SPE was 84.1 % and by LLE it was 77.4 % (p value <0.05). Moreover, the average number of metabolites isolated by SPE and LLE was 161.8 ± 18.6 and 140.1 ± 20.4 respectively. The processing cost of LLE was economical. In a cost constraint setting using LLE may be the practical option if used for organic acid analysis. PMID:27605738

  14. Spectral optimization of color temperature tunable white LEDs with excellent color rendering and luminous efficacy.

    PubMed

    He, Guoxing; Tang, Ju

    2014-10-01

    The optimization model of limited luminous efficacy (LLE) for correlated color temperature (CCT) tunable phosphor-coated white light-emitting diodes (pc-W LEDs) consisting of blue chips, green and yellow phosphors, and red chips, including downconversion energy loss, has been developed under the constraint of a designated color-rendering index (CRI) and a special CRI of R9 for strong red. The optimal spectra of pc-W LEDs are obtained with a nonlinear program for maximizing LLE under conditions of both CRI and R9 above 90, 95, and 98 at CCTs of 2700-6500 K. The pc-W LEDs with LLE>301  lm/W for both CRI and R9 above 90, LLE>290  lm/W for both CRI and R9 above 95, and LLE>276  lm/W for both CRI and R9 above 98 could be achieved at CCTs of 2700-6500 K. The recommended peak wavelengths and full widths at half-maximum (FWHMs) for the current LEDs and phosphors and their photometric and colorimetric performances are presented. PMID:25360930

  15. Miniaturized preconcentration methods based on liquid-liquid extraction and their application in inorganic ultratrace analysis and speciation: A review

    NASA Astrophysics Data System (ADS)

    Pena-Pereira, Francisco; Lavilla, Isela; Bendicho, Carlos

    2009-01-01

    Liquid-liquid extraction (LLE) is widely used as a pre-treatment technique for separation and preconcentration of both organic and inorganic analytes from aqueous samples. Nevertheless, it has several drawbacks, such as emulsion formation or the use of large volumes of solvents, which makes LLE expensive and labour intensive. Therefore, miniaturization of conventional liquid-liquid extraction is needed. The search for alternatives to the conventional LLE using negligible volumes of extractant and the minimum number of steps has driven the development of three new miniaturized methodologies, i.e. single-drop microextraction (SDME), hollow fibre liquid-phase microextraction (HF-LPME) and dispersive liquid-liquid microextraction (DLLME). The aim of this paper is to provide an overview of these novel preconcentration approaches and their potential use in analytical labs involved in inorganic (ultra)trace analysis and speciation. Relevant applications to the determination of metal ions, metalloids, organometals and non-metals are included.

  16. The Fifth Omega Laser Facility Users Group Workshop

    SciTech Connect

    Petrasso, R. D.

    2015-10-01

    A capacity gathering of over 100 researchers from 25 universities and laboratories met at the Laboratory for Laser Energetics (LLE) for the Fifth Omega Laser Facility Users Group (OLUG) workshop. The purpose of the 2.5-day workshop was to facilitate communications and exchanges among individual Omega users and between users and the LLE management; to present ongoing and proposed research; to encourage research opportunities and collaborations that could be undertaken at the Omega Laser Facility and in a complementary fashion at other facilities [such as the National Ignition Facility (NIF) or the Laboratoire pour l’Utilisation des Lasers Intenses (LULI)]; to provide an opportunity for students, postdoctoral fellows, and young researchers to present their research in an informal setting; and to provide feedback to LLE management from the users about ways to improve the facility and future experimental campaigns.

  17. A simple liquid extraction protocol for overcoming the ion suppression of triacylglycerols by phospholipids in liquid chromatography mass spectrometry studies.

    PubMed

    Araujo, Pedro; Tilahun, Ephrem; Breivik, Joar Fjørtoft; Abdulkader, Bashir M; Frøyland, Livar; Zeng, Yingxu

    2016-02-01

    It is well-known that triacylglycerol (TAG) ions are suppressed by phospholipid (PL) ions in regiospecific analysis of TAG by mass spectrometry (MS). Hence, it is essential to remove the PL during sample preparation prior to MS analysis. The present article proposes a cost-effective liquid-liquid extraction (LLE) method to remove PL from TAG in different kinds of biological samples by using methanol, hexane and water. High performance thin layer chromatography confirmed the lack of PL in krill oil and salmon liver samples, submitted to the proposed LLE protocol, and liquid chromatography tandem MS confirmed that the identified TAG ions were highly enhanced after implementing the LLE procedure. PMID:26653473

  18. Locally linear embedding: dimension reduction of massive protostellar spectra

    NASA Astrophysics Data System (ADS)

    Ward, J. L.; Lumsden, S. L.

    2016-09-01

    We present the results of the application of locally linear embedding (LLE) to reduce the dimensionality of dereddened and continuum subtracted near-infrared spectra using a combination of models and real spectra of massive protostars selected from the Red MSX Source survey data base. A brief comparison is also made with two other dimension reduction techniques; principal component analysis (PCA) and Isomap using the same set of spectra as well as a more advanced form of LLE, Hessian locally linear embedding. We find that whilst LLE certainly has its limitations, it significantly outperforms both PCA and Isomap in classification of spectra based on the presence/absence of emission lines and provides a valuable tool for classification and analysis of large spectral data sets.

  19. Development of a harmonised method for the profiling of amphetamines: IV. Optimisation of sample preparation.

    PubMed

    Andersson, Kjell; Jalava, Kaisa; Lock, Eric; Huizer, Henk; Kaa, Elisabet; Lopes, Alvaro; Poortman-van der Meer, Anneke; Cole, Michael D; Dahlén, Johan; Sippola, Erkki

    2007-06-14

    The suitability of liquid-liquid extraction (LLE) and solid-phase extraction (SPE) for the preparation of impurity extracts intended for gas chromatographic profiling analyses of amphetamine were evaluated. Both techniques were optimised with respect to the extraction of selected target compounds by use of full factorial designs in which the variables affecting the performance were evaluated. Test samples consisted of amphetamine synthesised by the Leuckart reaction, by reductive amination of benzyl methyl ketone and by the nitrostyrene route. The performance of LLE and SPE were comparable in terms of repeatability and recovery of the target compounds. LLE was considered the better choice for the present harmonised amphetamine profiling method due to the lack of information on the long-term stability of SPE columns. PMID:17134863

  20. Discovery of novel 5,6,7,8-tetrahydro[1,2,4]triazolo[4,3-a]pyridine derivatives as γ-secretase modulators (Part 2).

    PubMed

    Takai, Takafumi; Koike, Tatsuki; Nakamura, Minoru; Kajita, Yuichi; Yamashita, Toshiro; Taya, Naohiro; Tsukamoto, Tetsuya; Watanabe, Tomomichi; Murakami, Koji; Igari, Tomoko; Kamata, Makoto

    2016-07-15

    γ-Secretase modulators (GSMs), which lower pathogenic amyloid beta (Aβ) without affecting the production of total Aβ or Notch signal, have emerged as a potential therapeutic agent for Alzheimer's disease (AD). A novel series of 5,6,7,8-tetrahydro[1,2,4]triazolo[4,3-a]pyridine derivatives was discovered and characterized as GSMs. Optimization of substituents at the 8-position of the core scaffold using ligand-lipophilicity efficiency (LLE) as a drug-likeness guideline led to identification of various types of high-LLE GSMs. Phenoxy compound (R)-17 exhibited especially high LLE as well as potent in vivo Aβ42-lowering effect by single administration. Furthermore, multiple oral administration of (R)-17 significantly reduced soluble and insoluble brain Aβ42, and ameliorated cognitive deficit in novel object recognition test (NORT) using Tg2576 mice as an AD model. PMID:27255179

  1. The Sixth Omega Laser Facility Users Group Workshop

    SciTech Connect

    Petrasso, R. D.

    2014-10-01

    A capacity gathering of over 100 researchers from 25 universities and laboratories met at the Laboratory for Laser Energetics (LLE) for the Sixth Omega Laser Facility Users Group (OLUG) workshop. The purpose of the 2.5-day workshop was to facilitate communications and exchanges among individual OMEGA users, and between users and the LLE management; to present ongoing and proposed research; to encourage research opportunities and collaborations that could be undertaken at the Omega Laser Facility and in a complementary fashion at other facilities [such as the National Ignition Facility (NIF) or the Laboratoire pour l’Utilisation des Lasers Intenses (LULI)]; to provide an opportunity for students, postdoctoral fellows, and young researchers to present their research in an informal setting; and to provide feedback from the users to LLE management about ways to improve and keep the facility and future experimental campaigns at the cutting edge.

  2. Comparison of two extraction methods for evaluation of volatile constituents patterns in commercial whiskeys Elucidation of the main odour-active compounds.

    PubMed

    Caldeira, M; Rodrigues, F; Perestrelo, R; Marques, J C; Câmara, J S

    2007-11-15

    An analytical procedure based on manual dynamic headspace solid-phase microextraction (HS-SPME) method and the conventional extraction method by liquid-liquid extraction (LLE), were compared for their effectiveness in the extraction and quantification of volatile compounds from commercial whiskey samples. Seven extraction solvents covering a wide range of polarities and two SPME fibres coatings, has been evaluated. The highest amounts extracted, were achieved using dichloromethane (CH2Cl2) by LLE method (LLE(CH2Cl2)) and using a CAR/PDMS fibre (SPME(CAR/PDMS)) in HS-SPME. Each method was used to determine the responses of 25 analytes from whiskeys and calibration standards, in order to provide sensitivity comparisons between the two methods. Calibration curves were established in a synthetic whiskey and linear correlation coefficient (r) were greater than 0.9929 for LLE(CH2Cl2) and 0.9935 for SPME(CAR/PDMS), for all target compounds. Recoveries greater than 80% were achieved. For most compounds, precision (expressed by relative standard deviation, R.S.D.) are very good, with R.S.D. values lower than 14.78% for HS-SPME method and than 19.42% for LLE method. The detection limits ranged from 0.13 to 19.03 microg L(-1) for SPME procedure and from 0.50 to 12.48 microg L(-1) for LLE. A tentative study to estimate the contribution of a specific compound to the aroma of a whiskey, on the basis of their odour activity values (OAV) was made. Ethyl octanoate followed by isoamyl acetate and isobutyl alcohol, were found the most potent odour-active compounds. PMID:18371616

  3. Base-Catalyzed Depolymerization of Lignin: Separation of Monomers

    SciTech Connect

    Vigneault, A.; Johnson, D. K.; Chornet, E.

    2007-12-01

    In our quest for fractionating lignocellulosic biomass and valorizing specific constitutive fractions, we have developed a strategy for the separation of 12 added value monomers generated during the hydrolytic based-catalyzed depolymerization of a Steam Exploded Aspen Lignin. The separation strategy combines liquid-liquid-extraction (LLE), followed by vacuum distillation, liquid chromatography (LC) and crystallization. LLE, vacuum distillation and flash LC were tested experimentally. Batch vacuum distillation produced up to 4 fractions. Process simulation confirmed that a series of 4 vacuum distillation columns could produce 5 distinct monomer streams, 3 of which require further chromatography and crystallization for purification.

  4. Risk equivalent of exposure versus dose of radiation

    SciTech Connect

    Bond, V.P.

    1986-01-01

    This report describes a risk analysis study of low-dose irradiation and the resulting biological effects on a cell. The author describes fundamental differences between the effects of high-level exposure (HLE) and low-level exposure (LLE). He stresses that the concept of absorbed dose to an organ is not a dose but a level of effect produced by a particular number of particles. He discusses the confusion between a linear-proportional representation of dose limits and a threshold-curvilinear representation, suggesting that a LLE is a composite of both systems. (TEM)

  5. Prospective Changes in Infertile Patients using Nonlinear Analysis

    NASA Astrophysics Data System (ADS)

    Takahashi, Yuko; Tomiyama, Tatsuhiro; Matsubayashi, Hidehiko; Tsukamoto, Asami; Oyama-Higa, Mayumi

    2011-06-01

    We measured pulse waves in 22 infertile women from the beginning of in vitro fertilization-embryo transfer (IVF-ET) through to pregnancy testing. The largest Lyapunov exponent (LLE) and autonomic nerve balance in the pregnancy group were significantly lower than that in the non-pregnancy group. In this study, we measured plethysmograms of four women who became pregnant and 18 who did not, ten times from each. We calculated LLE and a value for the autonomic nerve balance; from this analysis, we conclude that a mental state that allows for the possibility of becoming pregnant is necessary for a successful pregnancy.

  6. Comparative evaluation of the efficiency of low-cost adsorbents and ligninolytic fungi to remove a combination of xenoestrogens and pesticides from a landfill leachate and abate its phytotoxicity.

    PubMed

    Loffredo, Elisabetta; Castellana, Giancarlo

    2015-01-01

    In this study, two widely available low-cost adsorbents, almond shells and a green compost, and two ligninolytic fungi, Pleurotus ostreatus and Stereum hirsutum, were used to remove organic contaminants from a landfill leachate (LLe) and abate its phytotoxicity. The methodology adopted was based on the occurrence of two simultaneous processes, such as adsorption and bioremoval. The leachate was artificially contaminated with a mixture of the xenoestrogens bisphenol A (BPA), ethynilestadiol (EE2) and 4-n-nonylphenol (NP), the herbicide linuron and the insecticide dimethoate at concentrations of 10, 1, 1, 10 and 10 mg L(-1), respectively. Three adsorption substrates were prepared: potato dextrose agar alone or the same incorporating each adsorbent. The substrates were either not inoculated or inoculated with each fungus, separately, before to be superimposed on LLe. After 2 months, the residual amount of each contaminant, the electrical conductivity, the pH and the content of total phenols were measured in treated LLe. Germination assays using lettuce, ryegrass and radish were performed to evaluate LLe phytotoxicity. The combination substrate+P. ostreatus showed the best results with average removals of 88, 96, 99, 58 and 46% for BPA, EE2, NP, linuron and dimethoate, respectively. The same treatment considerably reduced the phenol content in LLe compared to no treatment. The combination substrate+S. hirsutum produced average removals of 39, 71, 100, 61 and 32% for BPA, EE2, NP, linuron and dimethoate, respectively. Also uninoculated substrates showed relevant adsorption capacities towards the five contaminants. Most treatments significantly reduced LLe phytotoxicity, especially on lettuce. The best results were obtained with the treatment compost+S. hirsutum, which produced root and shoot lengths and seedling biomass of lettuce, respectively, 2.3, 3.3, and 1.9 times those measured in untreated LLe. In general, germination results were negatively correlated with LLe

  7. Determination of the Spatial Location of Coke in Catalysts by a Novel NMR Approach

    NASA Astrophysics Data System (ADS)

    Gopinathan, Navin; Rigby, Sean; Greaves, Malcolm; Lowe, John; Wood, Joseph; Dong, Leilei

    2011-03-01

    In this work, a liquid-liquid exchange (LLE) process within nanoporous heterogeneous catalysts has been followed using NMR relaxometry. Under so-called `metered' supply conditions, when a high affinity liquid (water) displaced a low affinity liquid (cyclohexane) from a nanoporous sol-gel silica, entrapment of the low affinity liquid was observed which was similar to that observed in mercury porosimetry. In a similar experiment, comparing LLE in fresh and coked samples of bimodal Pt-alumina catalyst pellets, it was found that, while for the fresh sample water initially displaced cyclohexane from the smallest pores, as expected under metered conditions, this did not occur for coked catalysts.

  8. Optimizing Ligand Efficiency of Selective Androgen Receptor Modulators (SARMs).

    PubMed

    Handlon, Anthony L; Schaller, Lee T; Leesnitzer, Lisa M; Merrihew, Raymond V; Poole, Chuck; Ulrich, John C; Wilson, Joseph W; Cadilla, Rodolfo; Turnbull, Philip

    2016-01-14

    A series of selective androgen receptor modulators (SARMs) containing the 1-(trifluoromethyl)benzyl alcohol core have been optimized for androgen receptor (AR) potency and drug-like properties. We have taken advantage of the lipophilic ligand efficiency (LLE) parameter as a guide to interpret the effect of structural changes on AR activity. Over the course of optimization efforts the LLE increased over 3 log units leading to a SARM 43 with nanomolar potency, good aqueous kinetic solubility (>700 μM), and high oral bioavailability in rats (83%). PMID:26819671

  9. Advanced liquid and solid extraction procedures for ultratrace determination of rhenium by radiochemical neutron activation analysis

    NASA Astrophysics Data System (ADS)

    Mizera, J.; Kučera, J.; Řanda, Z.; Lučaníková, M.

    2006-01-01

    Radiochemical neutron activation analysis (RNAA) procedures for determination of Re at the ultratrace level based on use of liquid-liquid extraction (LLE) and extraction chromatography (EXC) have been developed. Two different LLE procedures were used depending on the way of sample decomposition using either 2-butanone or tetraphenylarsonium chloride in CHCl3. EXC employed new solid extractant materials prepared by incorporation of the liquid trioctyl-methyl-ammonium chloride into an inert polyacrylonitrile matrix. The RNAA procedures presented have been compared and applied for Re determination in several biological and environmental reference materials.

  10. Plethysmogram and EEG: Effects of Music and Voice Sound

    NASA Astrophysics Data System (ADS)

    Miao, Tiejun; Oyama-Higa, Mayumi; Sato, Sadaka; Kojima, Junji; Lin, Juan; Reika, Sato

    2011-06-01

    We studied a relation of chaotic dynamics of finger plethysmogram to complexity of high cerebral center in both theoretical and experimental approaches. We proposed a mathematical model to describe emergence of chaos in finger tip pulse wave, which gave a theoretical prediction indicating increased chaoticity in higher cerebral center leading to an increase of chaos dynamics in plethysmograms. We designed an experiment to observe scalp-EEG and finger plethysmogram using two mental tasks to validate the relationship. We found that scalp-EEG showed an increase of the largest Lyapunov exponents (LLE) during speaking certain voices. Topographical scalp map of LLE showed enhanced arise around occipital and right cerebral area. Whereas there was decreasing tendency during listening music, where LLE scalp map revealed a drop around center cerebral area. The same tendency was found for LLE obtained from finger plethysmograms as ones of EEG under either speaking or listening tasks. The experiment gave results that agreed well with the theoretical relation derived from our proposed model.

  11. Bearing Fault Diagnosis Based on Statistical Locally Linear Embedding

    PubMed Central

    Wang, Xiang; Zheng, Yuan; Zhao, Zhenzhou; Wang, Jinping

    2015-01-01

    Fault diagnosis is essentially a kind of pattern recognition. The measured signal samples usually distribute on nonlinear low-dimensional manifolds embedded in the high-dimensional signal space, so how to implement feature extraction, dimensionality reduction and improve recognition performance is a crucial task. In this paper a novel machinery fault diagnosis approach based on a statistical locally linear embedding (S-LLE) algorithm which is an extension of LLE by exploiting the fault class label information is proposed. The fault diagnosis approach first extracts the intrinsic manifold features from the high-dimensional feature vectors which are obtained from vibration signals that feature extraction by time-domain, frequency-domain and empirical mode decomposition (EMD), and then translates the complex mode space into a salient low-dimensional feature space by the manifold learning algorithm S-LLE, which outperforms other feature reduction methods such as PCA, LDA and LLE. Finally in the feature reduction space pattern classification and fault diagnosis by classifier are carried out easily and rapidly. Rolling bearing fault signals are used to validate the proposed fault diagnosis approach. The results indicate that the proposed approach obviously improves the classification performance of fault pattern recognition and outperforms the other traditional approaches. PMID:26153771

  12. Bearing Fault Diagnosis Based on Statistical Locally Linear Embedding.

    PubMed

    Wang, Xiang; Zheng, Yuan; Zhao, Zhenzhou; Wang, Jinping

    2015-01-01

    Fault diagnosis is essentially a kind of pattern recognition. The measured signal samples usually distribute on nonlinear low-dimensional manifolds embedded in the high-dimensional signal space, so how to implement feature extraction, dimensionality reduction and improve recognition performance is a crucial task. In this paper a novel machinery fault diagnosis approach based on a statistical locally linear embedding (S-LLE) algorithm which is an extension of LLE by exploiting the fault class label information is proposed. The fault diagnosis approach first extracts the intrinsic manifold features from the high-dimensional feature vectors which are obtained from vibration signals that feature extraction by time-domain, frequency-domain and empirical mode decomposition (EMD), and then translates the complex mode space into a salient low-dimensional feature space by the manifold learning algorithm S-LLE, which outperforms other feature reduction methods such as PCA, LDA and LLE. Finally in the feature reduction space pattern classification and fault diagnosis by classifier are carried out easily and rapidly. Rolling bearing fault signals are used to validate the proposed fault diagnosis approach. The results indicate that the proposed approach obviously improves the classification performance of fault pattern recognition and outperforms the other traditional approaches. PMID:26153771

  13. Factors Mititating against the Establishment, Development, Management and Utilization of Instructional Television (ITV) in Higher Institutions in Nigeria

    ERIC Educational Resources Information Center

    Sofowora, Olaniyi Alaba

    2007-01-01

    This paper highlights the problems facing the establishment, development, management and utilization of instructional television (ITV) in higher institutions in Nigeria. The paper also discusses chronicle of activities and achievements made at Obafemi Awolowo University, lle-lfe in the effort at revamping the television system. Obafemi Awolowo…

  14. Late Language Emergence at 24 Months: An Epidemiological Study of Prevalence, Predictors, and Covariates

    ERIC Educational Resources Information Center

    Zubrick, Stephen R.; Taylor, Catherine L.; Rice, Mabel L.; Slegers, David W.

    2007-01-01

    Purpose: The primary objectives of this study were to determine the prevalence of late language emergence (LLE) and to investigate the predictive status of maternal, family, and child variables. Method: This is a prospective cohort study of 1,766 epidemiologically ascertained 24-month-old singleton children. The framework was an ecological model…

  15. Final Report: Development of X-ray tracer diagnostics for radiatively-driven ablator experiments, November 1, 1997 - October 31, 1998

    SciTech Connect

    MacFarlane, J.J.; Cohen, D.H.; Ping Wang, G.A.; Moses, R.R.; Peterson, P.A.; Jaanimagi; Landen, O.L.; Olson, R.E.; Murphy, T.J.; Magelssen, G.R.; Delamater, N.D.

    1999-06-01

    This is a combined experimental and theoretical analysis of tracer layers as spectral diagnostics for radiation burn-through of ablator materials. German-doped plastic is attached as a witness plate to a laser driven hohlraum. Backlit absorption spectroscopy is used as a diagnostic. Target shots were performed on the OMEGSA laser at UR/LLE.

  16. Simultaneous Promotion of Indigenisation and Internationalisation: New Language-in-Education Policy in Taiwan

    ERIC Educational Resources Information Center

    Chen, Su-Chiao

    2006-01-01

    The indigenisation and internationalisation of Taiwan emerged as issues of national concern as a result of the democratisation of politics in the late 1980s which profoundly changed the sociopolitical and economic climate. One manifestation of these changes was "new" language-in-education policies. These were the Local-Language-in-Education (LLE)…

  17. Late Language Emergence in 24-Month-Old Twins: Heritable and Increased Risk for Late Language Emergence in Twins

    ERIC Educational Resources Information Center

    Rice, Mabel L.; Zubrick, Stephen R.; Taylor, Catherine L.; Gayán, Javier; Bontempo, Daniel E.

    2014-01-01

    Purpose: This study investigated the etiology of late language emergence (LLE) in 24-month-old twins, considering possible twinning, zygosity, gender, and heritability effects for vocabulary and grammar phenotypes. Method: A population-based sample of 473 twin pairs participated. Multilevel modeling estimated means and variances of vocabulary and…

  18. Low tritium partial pressure permeation system for mass transport measurement in lead lithium eutectic

    DOE PAGESBeta

    Pawelko, R. J.; Shimada, M.; Katayama, K.; Fukada, S.; Humrickhouse, P. W.; Terai, T.

    2015-11-28

    This paper describes a new experimental system designed to investigate tritium mass transfer properties in materials important to fusion technology. Experimental activities were carried out at the Safety and Tritium Applied Research (STAR) facility located at the Idaho National Laboratory (INL). The tritium permeation measurement system was developed as part of the Japan/US TITAN collaboration to investigate tritium mass transfer properties in liquid lead lithium eutectic (LLE) alloy. The experimental system is configured to measure tritium mass transfer properties at low tritium partial pressures. Initial tritium permeation scoping tests were conducted on a 1 mm thick α-Fe plate to determinemore » operating parameters and to validate the experimental technique. A second series of permeation tests was then conducted with the α-Fe plate covered with an approximately 8.5 mm layer of liquid lead lithium eutectic alloy (α-Fe/LLE). We present preliminary tritium permeation data for α-Fe and α-Fe/LLE at temperatures between 400 and 600°C and at tritium partial pressures between 1.7E-3 and 2.5 Pa in helium. Preliminary results for the α-Fe plate and α-Fe/LLE indicate that the data spans a transition region between the diffusion-limited regime and the surface-limited regime. In conclusion, additional data is required to determine the existence and range of a surface-limited regime.« less

  19. Low tritium partial pressure permeation system for mass transport measurement in lead lithium eutectic

    SciTech Connect

    Pawelko, R. J.; Shimada, M.; Katayama, K.; Fukada, S.; Humrickhouse, P. W.; Terai, T.

    2015-11-28

    This paper describes a new experimental system designed to investigate tritium mass transfer properties in materials important to fusion technology. Experimental activities were carried out at the Safety and Tritium Applied Research (STAR) facility located at the Idaho National Laboratory (INL). The tritium permeation measurement system was developed as part of the Japan/US TITAN collaboration to investigate tritium mass transfer properties in liquid lead lithium eutectic (LLE) alloy. The experimental system is configured to measure tritium mass transfer properties at low tritium partial pressures. Initial tritium permeation scoping tests were conducted on a 1 mm thick α-Fe plate to determine operating parameters and to validate the experimental technique. A second series of permeation tests was then conducted with the α-Fe plate covered with an approximately 8.5 mm layer of liquid lead lithium eutectic alloy (α-Fe/LLE). We present preliminary tritium permeation data for α-Fe and α-Fe/LLE at temperatures between 400 and 600°C and at tritium partial pressures between 1.7E-3 and 2.5 Pa in helium. Preliminary results for the α-Fe plate and α-Fe/LLE indicate that the data spans a transition region between the diffusion-limited regime and the surface-limited regime. In conclusion, additional data is required to determine the existence and range of a surface-limited regime.

  20. In vitro and in vivo evaluation of inhibition activity of lotus (Nelumbo nucifera Gaertn.) leaves against ultraviolet B-induced phototoxicity.

    PubMed

    Huang, Bo; Zhu, Ling; Liu, Song; Li, Dong; Chen, Yuxin; Ma, Bingxin; Wang, Youwei

    2013-04-01

    Lotus (Nelumbo nucifera Gaertn.), an aquatic vegetable, is extensively cultivated in eastern Asia, particularly in China. Our previous study showed that lotus leaf extracts (LLEs) have strong antioxidant effects in vitro and in vivo. The main antioxidants in lotus leaf have been identified via liquid chromatography-mass spectrometry. Ultraviolet B (UVB) protective effects have been associated with plant extracts rich in antioxidants. The current study focuses on the mitochondria model to evaluate the potent inhibition activity of LLE against UVB-induced phototoxicity. The level of thiobarbituric acid reactive substances, glutathione, lipid hydroperoxide, conjugated diene, and 4-hydroxynonenal were measured. The in vivo activity of LLE was also investigated in mice model. The results showed that all concentrations of LLE (10, 100, and 1000μg/ml) possessed strong protective effect against UVB-induced phototoxicity in the mitochondria model. The in vivo test showed that LLE have significant protective effects on the level of superoxide dismutase, catalase, and glutathione peroxidase, as well as the contents of hydroxyproline and malondialdehyde in the skin samples. This study would provide a foundation for broadening the applications of lotus leaf in both the medical and food industries. PMID:23474526

  1. Expression of fibronectin binding protein A (FnBPA) from Staphylococcus aureus at the cell surface of Lactococcus lactis improves its immunomodulatory properties when used as protein delivery vector.

    PubMed

    Almeida, Juliana F; Breyner, Natalia M; Mahi, Miloud; Ahmed, Bensoltane; Benbouziane, Bouasria; Boas, Priscilla C B Vilas; Miyoshi, Anderson; Azevedo, Vasco; Langella, Philippe; Bermúdez-Humarán, Luis G; Chatel, Jean-Marc

    2016-03-01

    A recombinant strain of Lactococcus lactis displaying a cell-surface anchored fibronectin binding protein A (FnBPA) from Staphylococcus aureus (LL-FnBPA) had been shown to be more efficient in delivering plasmid than its wild-type counterpart both in vitro and in vivo, and have the ability to orientate the immune response toward a Th2 profile in a context of a DNA vaccination. The aim of this work was to test whether this LL-FnBPA strain could shape the immune response after mucosal administration in mice. For this, we used a mouse model of human papilloma virus (HPV)-induced cancer and a L. lactis strain displaying at its cell surface both HPV-16-E7 antigen (LL-E7) and FnBPA (LL-E7+FnBPA). Our results revealed a more efficient systemic Th1 immune response with recombinant LL-E7+FnBPA. Furthermore, mice vaccinated with LL-E7+FnBPA were better protected when challenged with HPV-16-induced tumors. Altogether, the results suggest that FnBPA displays adjuvant properties when used in the context of mucosal delivery using L. lactis as a live vector. PMID:26854905

  2. Sparsity divergence index based on locally linear embedding for hyperspectral anomaly detection

    NASA Astrophysics Data System (ADS)

    Zhang, Lili; Zhao, Chunhui

    2016-04-01

    Hyperspectral imagery (HSI) has high spectral and spatial resolutions, which are essential for anomaly detection (AD). Many anomaly detectors assume that the spectrum signature of HSI pixels can be modeled with a Gaussian distribution, which is actually not accurate and often leads to many false alarms. Therefore, a sparsity model without any distribution hypothesis is usually employed. Dimensionality reduction (DR) as a preprocessing step for HSI is important. Principal component analysis as a conventional DR method is a linear projection and cannot exploit the nonlinear properties in hyperspectral data, whereas locally linear embedding (LLE) as a local, nonlinear manifold learning algorithm works well for DR of HSI. A modified algorithm of sparsity divergence index based on locally linear embedding (SDI-LLE) is thus proposed. First, kernel collaborative representation detection is adopted to calculate the sparse dictionary matrix of local reconstruction weights in LLE. Then, SDI is obtained both in the spectral and spatial domains, where spatial SDI is computed after DR by LLE. Finally, joint SDI, combining spectral SDI and spatial SDI, is computed, and the optimal SDI is performed for AD. Experimental results demonstrate that the proposed algorithm significantly improves the performance, when compared with its counterparts.

  3. Intrinsic modulation of ENSO predictability viewed through a local Lyapunov lens

    NASA Astrophysics Data System (ADS)

    Karamperidou, Christina; Cane, Mark A.; Lall, Upmanu; Wittenberg, Andrew T.

    2013-04-01

    The presence of rich ENSO variability in the long unforced simulation of GFDL's CM2.1 motivates the use of tools from dynamical systems theory to study variability in ENSO predictability, and its connections to ENSO magnitude, frequency, and physical evolution. Local Lyapunov exponents (LLEs) estimated from the monthly NINO3 SSTa model output are used to characterize periods of increased or decreased predictability. The LLEs describe the growth of infinitesimal perturbations due to internal variability, and are a measure of the immediate predictive uncertainty at any given point in the system phase-space. The LLE-derived predictability estimates are compared with those obtained from the error growth in a set of re-forecast experiments with CM2.1. It is shown that the LLEs underestimate the error growth for short forecast lead times (less than 8 months), while they overestimate it for longer lead times. The departure of LLE-derived error growth rates from the re-forecast rates is a linear function of forecast lead time, and is also sensitive to the length of the time series used for the LLE calculation. The LLE-derived error growth rate is closer to that estimated from the re-forecasts for a lead time of 4 months. In the 2,000-year long simulation, the LLE-derived predictability at the 4-month lead time varies (multi)decadally only by 9-18 %. Active ENSO periods are more predictable than inactive ones, while epochs with regular periodicity and moderate magnitude are classified as the most predictable by the LLEs. Events with a deeper thermocline in the west Pacific up to five years prior to their peak, along with an earlier deepening of the thermocline in the east Pacific in the months preceding the peak, are classified as more predictable. Also, the GCM is found to be less predictable than nature under this measure of predictability.

  4. Intrinsic modulation of ENSO predictability viewed through a local Lyapunov lens

    NASA Astrophysics Data System (ADS)

    Karamperidou, Christina; Cane, Mark A.; Lall, Upmanu; Wittenberg, Andrew T.

    2014-01-01

    The presence of rich ENSO variability in the long unforced simulation of GFDL's CM2.1 motivates the use of tools from dynamical systems theory to study variability in ENSO predictability, and its connections to ENSO magnitude, frequency, and physical evolution. Local Lyapunov exponents (LLEs) estimated from the monthly NINO3 SSTa model output are used to characterize periods of increased or decreased predictability. The LLEs describe the growth of infinitesimal perturbations due to internal variability, and are a measure of the immediate predictive uncertainty at any given point in the system phase-space. The LLE-derived predictability estimates are compared with those obtained from the error growth in a set of re-forecast experiments with CM2.1. It is shown that the LLEs underestimate the error growth for short forecast lead times (less than 8 months), while they overestimate it for longer lead times. The departure of LLE-derived error growth rates from the re-forecast rates is a linear function of forecast lead time, and is also sensitive to the length of the time series used for the LLE calculation. The LLE-derived error growth rate is closer to that estimated from the re-forecasts for a lead time of 4 months. In the 2,000-year long simulation, the LLE-derived predictability at the 4-month lead time varies (multi)decadally only by 9-18 %. Active ENSO periods are more predictable than inactive ones, while epochs with regular periodicity and moderate magnitude are classified as the most predictable by the LLEs. Events with a deeper thermocline in the west Pacific up to five years prior to their peak, along with an earlier deepening of the thermocline in the east Pacific in the months preceding the peak, are classified as more predictable. Also, the GCM is found to be less predictable than nature under this measure of predictability.

  5. Optimal spectra of white LED integrated with quantum dots for mesopic vision.

    PubMed

    Zan, Linlin; Lin, Duyang; Zhong, Ping; He, Guoxing

    2016-04-01

    The spectral optimization model for limited mesopic luminous efficacy (LLEm) of white LED integrated with quantum dots (QD-WLED) consisting of a blue chip, green, yellow and red quantum dots, including down-conversion energy loss, was developed under constraint of designated color rendering properties. The optimal spectra of QD-WLEDs with CRI ≥ 70 and CQS ≥ 60 as well as CRI ≥ 85 and CQS ≥ 85 for mesopic vision, photometric and colorimetric performances at correlated color temperature of 2700 K to 45000 K, as well as the LLEms of optimal QD-WLEDs for four road lighting standards of the USA and the UK were presented. These results suggest that QD-WLEDs make strong candidates for replacing conventional light sources in the future as they enhance the vision quality in the road lighting in addition to energy saving. PMID:27137051

  6. Direct-Drive Inertial Fusion Research at the University of Rochester's Laboratory for Laser Energetics: A Review

    SciTech Connect

    McCrory, R.L.; Meyerhofer, D.D.; Loucks, S.J.; Skupsky, S.; Bahr, R.E.; Betti, R.; Boehly, T.R.; Craxton, R.S.; Collins, T.J.B.; Delettrez, J.A.; Donaldson, W.R.; Epstein, R.; Fletcher, K.A.; Freeman, C.; Frenje, J.A.; Glebov, V.Yu.; Goncharov, V.N.; Harding, D.R.; Jaanimagi, P.A.; Keck, R.L.; Kelly, J.H.; Kessler, T.J.; Kilkenny, J.D.; Knauer, J.P.; Li, C.K.; Lund, L.D.; Marozas, J.A.; McKenty, P.W.; Marshall, F.J.; Morse, S.F.B.; Padalino, S.; Petrasso, R.D.; Radha, P.B.; Regan, S.P.; Roberts, S.; Sangster, T.C.; Seguin, F.H.; Seka, W.; Smalyuk, V.A.; Soures, J.M.; Stoeckl, C.; Thorp, K.A.; Yaakobi, B.; Zuegel, J.D.

    2010-04-16

    This paper reviews the status of direct-drive inertial confinement fusion (ICF) research at the University of Rochester's Laboratory for Laser Energetics (LLE). LLE's goal is to demonstrate direct-drive ignition on the National Ignition Facility (NIF) by 2014. Baseline "all-DT" NIF direct-drive ignition target designs have been developed that have a predicted gain of 45 (1-D) at a NIF drive energy of ~1.6 MJ. Significantly higher gains are calculated for targets that include a DT-wicked foam ablator. This paper also reviews the results of both warm fuel and initial cryogenic-fuel spherical target implosion experiments carried out on the OMEGA UV laser. The results of these experiments and design calculations increase confidence that the NIF direct-drive ICF ignition goal will be achieved.

  7. TRITIUM OPERATIONS AT THE LABORATORY FOR LASER ENERGETICS

    SciTech Connect

    Shmayda, W.T.; Loucks, S.J.; Janezic, R.; Duffy, T.W.; Harding, D. R.; Lund, L.D.

    2006-05-17

    The Laboratory for Laser Energetics (LLE) at the University of Rochester has conducted inertial confinement fusion experiments since the early 1970s. Beginning in 1996, LLE filled and fielded targets containing DT gas with pressures as high as 30 atm. Facilities are being upgraded to prepare, characterize, and field targets with DT ice on their inner surface. To this end, process loops that can pressurize DT gas to 1200 bar and operate at 17 K are in the final stages of commissioning. To preclude both accidental and chronic tritium releases and to minimize the potential for exposures to personnel, both metal hydride-based and oxidation drier-based cleanup systems have been installed and commissioned with hydrogen. Cryogenic DT targets will be fielded in 2006.

  8. Sicherheitssysteme

    NASA Astrophysics Data System (ADS)

    Reif, Konrad

    Fahrerassistenzsysteme helfen, Unfälle zu vermeiden. Das Ziel ist das unfallfreie Fahren. Mit immer effizienteren elektronischen Systemen und verbesserter Sensorik versucht, diesem Ziel nahezukommen. Für die Fälle, in denen ein Unfall nicht verhindert werden kann, müssen die Unfallfolgen gemildert werden. Das erste passive Sicherheitssystem für Pkw wurde mit dem Sicherheitsgurt eingeführt. In Deutschland ist er für die Vordersitze seit 1970, für die Rücksitze seit 1979 vorgeschrieben. Die Gurtanlegepflicht wurde 1976 eingeführt. Die Elektronik ermöglichte seit den 1980 er- Jahren weitere Systeme, die die Sicherheit der Insassen im Falle eines Unfalls erhöhen.

  9. Evaluating source separation of plastic waste using conjoint analysis.

    PubMed

    Nakatani, Jun; Aramaki, Toshiya; Hanaki, Keisuke

    2008-11-01

    Using conjoint analysis, we estimated the willingness to pay (WTP) of households for source separation of plastic waste and the improvement of related environmental impacts, the residents' loss of life expectancy (LLE), the landfill capacity, and the CO2 emissions. Unreliable respondents were identified and removed from the sample based on their answers to follow-up questions. It was found that the utility associated with reducing LLE and with the landfill capacity were both well expressed by logarithmic functions, but that residents were indifferent to the level of CO2 emissions even though they approved of CO2 reduction. In addition, residents derived utility from the act of separating plastic waste, irrespective of its environmental impacts; that is, they were willing to practice the separation of plastic waste at home in anticipation of its "invisible effects", such as the improvement of citizens' attitudes toward solid waste issues. PMID:18207727

  10. Face Recognition Using ALLE and SIFT for Human Robot Interaction

    NASA Astrophysics Data System (ADS)

    Pan, Yaozhang; Ge, Shuzhi Sam; He, Hongsheng

    Face recognition is a very important aspect in developing human-robot interaction (HRI) for social robots. In this paper, an efficient face recognition algorithm is introduced for building intelligent robot vision system to recognize human faces. Dimension deduction algorithms locally linear embedding (LLE) and adaptive locally linear embedding (ALLE) and feature extraction algorithm scale-invariant feature transform (SIFT) are combined to form new methods called LLE-SIFT and ALLE-SIFT for finding compact and distinctive descriptors for face images. The new feature descriptors are demonstrated to have better performance in face recognition applications than standard SIFT descriptors, which shows that the proposed method is promising for developing robot vision system of face recognition.

  11. Gearbox fault diagnosis based on time-frequency domain synchronous averaging and feature extraction technique

    NASA Astrophysics Data System (ADS)

    Zhang, Shengli; Tang, Jiong

    2016-04-01

    Gearbox is one of the most vulnerable subsystems in wind turbines. Its healthy status significantly affects the efficiency and function of the entire system. Vibration based fault diagnosis methods are prevalently applied nowadays. However, vibration signals are always contaminated by noise that comes from data acquisition errors, structure geometric errors, operation errors, etc. As a result, it is difficult to identify potential gear failures directly from vibration signals, especially for the early stage faults. This paper utilizes synchronous averaging technique in time-frequency domain to remove the non-synchronous noise and enhance the fault related time-frequency features. The enhanced time-frequency information is further employed in gear fault classification and identification through feature extraction algorithms including Kernel Principal Component Analysis (KPCA), Multilinear Principal Component Analysis (MPCA), and Locally Linear Embedding (LLE). Results show that the LLE approach is the most effective to classify and identify different gear faults.

  12. Application of the largest Lyapunov exponent algorithm for feature extraction in low speed slew bearing condition monitoring

    NASA Astrophysics Data System (ADS)

    Caesarendra, Wahyu; Kosasih, Buyung; Tieu, Anh Kiet; Moodie, Craig A. S.

    2015-01-01

    This paper presents a new application of the largest Lyapunov exponent (LLE) algorithm for feature extraction method in low speed slew bearing condition monitoring. The LLE algorithm is employed to measure the degree of non-linearity of the vibration signal which is not easily monitored by existing methods. The method is able to detect changes in the condition of the bearing and demonstrates better tracking of the progressive deterioration of the bearing during the 139 measurement days than comparable methods such as the time domain feature methods based on root mean square (RMS), skewness and kurtosis extraction from the raw vibration signal and also better than extracting similar features from selected intrinsic mode functions (IMFs) of the empirical mode decomposition (EMD) result. The application of the method is demonstrated with laboratory slew bearing vibration data and industrial bearing data from a coal bridge reclaimer used in a local steel mill.

  13. CLASSIFICATION OF STELLAR SPECTRA WITH LOCAL LINEAR EMBEDDING

    SciTech Connect

    Daniel, Scott F.; Connolly, Andrew; Vanderplas, Jake; Schneider, Jeff; Xiong Liang

    2011-12-15

    We investigate the use of dimensionality reduction techniques for the classification of stellar spectra selected from the Sloan Digital Sky Survey. Using local linear embedding (LLE), a technique that preserves the local (and possibly nonlinear) structure within high-dimensional data sets, we show that the majority of stellar spectra can be represented as a one-dimensional sequence within a three-dimensional space. The position along this sequence is highly correlated with spectral temperature. Deviations from this 'stellar locus' are indicative of spectra with strong emission lines (including misclassified galaxies) or broad absorption lines (e.g., carbon stars). Based on this analysis, we propose a hierarchical classification scheme using LLE that progressively identifies and classifies stellar spectra in a manner that requires no feature extraction and that can reproduce the classic MK classifications to an accuracy of one type.

  14. Strahlungsfeldbedingungen bei der Ionisationsdosimetrie

    NASA Astrophysics Data System (ADS)

    Krieger, Hanno

    Bei der Dosimetrie von Photonenstrahlungen mit luftgefüllten Ionisationskammern werden in diesem Kapitel zwei Grenzfälle unterschieden. Der eine Fall ist die Bedingung des so genannten Sekundärelektronengleichwichts im Kammervolumen. In diesem Fall bestimmen ausschließlich die Photonen im Messvolumen die dosimetrische Anzeige. Der zweite Grenzfall ist gegeben, wenn das Luftvolumen und die Kammer das Strahlungsfeld im Phantom so wenig stören, dass der Sekundärelektronenfluss unverändert bleibt. Diese Bedingungen nennt man BRAGG-GRAY-Bedingungen. Beide Grenzfälle sind in der Praxis nur näherungsweise zu verwirklichen. Abweichungen müssen durch entsprechende Korrekturen oder Kalibrierungen berücksichtigt werden.

  15. RaPToRS Sample Delivery System

    NASA Astrophysics Data System (ADS)

    Henchen, Robert; Shibata, Kye; Krieger, Michael; Pogozelski, Edward; Padalino, Stephen; Glebov, Vladimir; Sangster, Craig

    2010-11-01

    At various labs (NIF, LLE, NRL), activated material samples are used to measure reaction properties. The Rapid Pneumatic Transport of Radioactive Samples (RaPToRS) system quickly and safely moves these radioactive samples through a closed PVC tube via airflow. The carrier travels from the reaction chamber to the control and analysis station, pneumatically braking at the outlet. A reversible multiplexer routes samples from various locations near the shot chamber to the analysis station. Also, the multiplexer allows users to remotely load unactivated samples without manually approaching the reaction chamber. All elements of the system (pneumatic drivers, flow control valves, optical position sensors, multiplexers, Geiger counters, and release gates at the analysis station) can be controlled manually or automatically using a custom LabVIEW interface. A prototype is currently operating at NRL in Washington DC. Prospective facilities for Raptors systems include LLE and NIF.

  16. Was the Risk from Nursing-Home Evacuation after the Fukushima Accident Higher than the Radiation Risk?

    PubMed Central

    Murakami, Michio; Ono, Kyoko; Tsubokura, Masaharu; Nomura, Shuhei; Oikawa, Tomoyoshi; Oka, Tosihiro; Kami, Masahiro; Oki, Taikan

    2015-01-01

    After the 2011 accident at the Fukushima Daiichi nuclear power plant, nursing-home residents and staff were evacuated voluntarily from damaged areas to avoid radiation exposure. Unfortunately, the evacuation resulted in increased mortalities among nursing home residents. We assessed the risk trade-off between evacuation and radiation for 191 residents and 184 staff at three nursing homes by using the same detriment indicator, namely loss of life expectancy (LLE), under four scenarios, i.e. “rapid evacuation (in accordance with the actual situation; i.e. evacuation on 22 March),” “deliberate evacuation (i.e. evacuation on 20 June),” “20-mSv exposure,” and “100-mSv exposure.” The LLE from evacuation-related mortality among nursing home residents was assessed with survival probability data from nursing homes in the city of Minamisoma and the city of Soma. The LLE from radiation mortality was calculated from the estimated age-specific mortality rates from leukemia and all solid cancers based on the additional effective doses and the survival probabilities. The total LLE of residents due to evacuation-related risks in rapid evacuation was 11,000 persons-d—much higher than the total LLEs of residents and staff due to radiation in the other scenarios (27, 1100, and 5800 persons-d for deliberate evacuation, 20 mSv-exposure, and 100 mSv-exposure, respectively). The latitude for reducing evacuation risks among nursing home residents is surprisingly large. Evacuation regulation and planning should therefore be well balanced with the trade-offs against radiation risks. This is the first quantitative assessment of the risk trade-off between radiation exposure and evacuation after a nuclear power plant accident. PMID:26359666

  17. Was the Risk from Nursing-Home Evacuation after the Fukushima Accident Higher than the Radiation Risk?

    PubMed

    Murakami, Michio; Ono, Kyoko; Tsubokura, Masaharu; Nomura, Shuhei; Oikawa, Tomoyoshi; Oka, Tosihiro; Kami, Masahiro; Oki, Taikan

    2015-01-01

    After the 2011 accident at the Fukushima Daiichi nuclear power plant, nursing-home residents and staff were evacuated voluntarily from damaged areas to avoid radiation exposure. Unfortunately, the evacuation resulted in increased mortalities among nursing home residents. We assessed the risk trade-off between evacuation and radiation for 191 residents and 184 staff at three nursing homes by using the same detriment indicator, namely loss of life expectancy (LLE), under four scenarios, i.e. "rapid evacuation (in accordance with the actual situation; i.e. evacuation on 22 March)," "deliberate evacuation (i.e. evacuation on 20 June)," "20-mSv exposure," and "100-mSv exposure." The LLE from evacuation-related mortality among nursing home residents was assessed with survival probability data from nursing homes in the city of Minamisoma and the city of Soma. The LLE from radiation mortality was calculated from the estimated age-specific mortality rates from leukemia and all solid cancers based on the additional effective doses and the survival probabilities. The total LLE of residents due to evacuation-related risks in rapid evacuation was 11,000 persons-d-much higher than the total LLEs of residents and staff due to radiation in the other scenarios (27, 1100, and 5800 persons-d for deliberate evacuation, 20 mSv-exposure, and 100 mSv-exposure, respectively). The latitude for reducing evacuation risks among nursing home residents is surprisingly large. Evacuation regulation and planning should therefore be well balanced with the trade-offs against radiation risks. This is the first quantitative assessment of the risk trade-off between radiation exposure and evacuation after a nuclear power plant accident. PMID:26359666

  18. Free trade negotiations can be harmful to your health.

    PubMed

    Krikorian, Gaëlle

    2006-12-01

    When negotiating free trade agreements (FTAs), the U.S. uses its considerable power to get countries to agree to intellectual property (IP) provisions that go beyond what is mandated in international IP accords. In this article, which is based on a poster presented at the conference, Gaëlle Krikorian describes the tactics used by the U.S. and explains how the results of its efforts can impede access to newer medicines in developing countries. PMID:17375436

  19. Electron Positron Proton Spectrometer for use at Laboratory for Laser Energetics

    SciTech Connect

    Ayers, S L

    2010-04-07

    The Electron Positron Proton Spectrometer (EPPS) is mounted in a TIM (Ten-Inch Manipulator) system on the Omega-60 or Omega-EP laser facilities at the University of Rochester, Laboratory for Laser Energetics (LLE), when in use, see Fig. 1. The Spectrometer assembly, shown in Fig. 2, is constructed of a steel box containing magnets, surrounded by Lead 6% Antimony shielding with SS threaded insert, sitting on an Aluminum 6061-T6 plate.

  20. Hyperspectral target detection using graph theory models and manifold geometry via an adaptive implementation of locally linear embedding

    NASA Astrophysics Data System (ADS)

    Ziemann, Amanda K.; Messinger, David W.

    2014-06-01

    Hyperspectral images comprise, by design, high dimensional image data. However, research has shown that for a d-dimensional hyperspectral image, it is typical for the data to inherently occupy an m-dimensional space, with m << d. In the remote sensing community, this has led to a recent increase in the use of non-linear manifold learning, which aims to characterize the embedded lower-dimensional, non-linear manifold upon which the hyperspectral data inherently lie. Classic hyperspectral data models include statistical, linear subspace, and linear mixture models, but these can place restrictive assumptions on the distribution of the data. With graph theory and manifold learning based models, the only assumption is that the data reside on an underlying manifold. In previous publications, we have shown that manifold coordinate approximation using locally linear embedding (LLE) is a viable pre-processing step for target detection with the Adaptive Cosine/Coherence Estimator (ACE) algorithm. Here, we improve upon that methodology using a more rigorous, data-driven implementation of LLE that incorporates the injection of a cloud" of target pixels and the Spectral Angle Mapper (SAM) detector. The LLE algorithm, which holds that the data is locally linear, is typically governed by a user defined parameter k, indicating the number of nearest neighbors to use in the initial graph model. We use an adaptive approach to building the graph that is governed by the data itself and does not rely upon user input. This implementation of LLE can yield greater separation between the target pixels and the background pixels in the manifold space. We present an analysis of target detection performance in the manifold coordinates using scene-derived target spectra and laboratory-measured target spectra across two different data sets.

  1. State Anxiety and Nonlinear Dynamics of Heart Rate Variability in Students

    PubMed Central

    Dimitriev, Aleksey D.

    2016-01-01

    Objectives Clinical and experimental research studies have demonstrated that the emotional experience of anxiety impairs heart rate variability (HRV) in humans. The present study investigated whether changes in state anxiety (SA) can also modulate nonlinear dynamics of heart rate. Methods A group of 96 students volunteered to participate in the study. For each student, two 5-minute recordings of beat intervals (RR) were performed: one during a rest period and one just before a university examination, which was assumed to be a real-life stressor. Nonlinear analysis of HRV was performed. The Spielberger’s State-Trait Anxiety Inventory was used to assess the level of SA. Results Before adjusting for heart rate, a Wilcoxon matched pairs test showed significant decreases in Poincaré plot measures, entropy, largest Lyapunov exponent (LLE), and pointwise correlation dimension (PD2), and an increase in the short-term fractal-like scaling exponent of detrended fluctuation analysis (α1) during the exam session, compared with the rest period. A Pearson analysis indicated significant negative correlations between the dynamics of SA and Poincaré plot axes ratio (SD1/SD2), and between changes in SA and changes in entropy measures. A strong negative correlation was found between the dynamics of SA and LLE. A significant positive correlation was found between the dynamics of SA and α1. The decreases in Poincaré plot measures (SD1, complex correlation measure), entropy measures, and LLE were still significant after adjusting for heart rate. Corrected α1 was increased during the exam session. As before, the dynamics of adjusted LLE was significantly correlated with the dynamics of SA. Conclusions The qualitative increase in SA during academic examination was related to the decrease in the complexity and size of the Poincaré plot through a reduction of both the interbeat interval and its variation. PMID:26807793

  2. Inertial confinement fusion target component fabrication and technology development support: Annual report, October 1, 1997--September 30, 1998

    SciTech Connect

    Gibson, J.

    1998-12-01

    During this period, General Atomics (GA) and their partner Schafer Corporation were assigned 17 formal tasks in support of the Inertial Confinement Fusion (ICF) program and its five laboratories. A portion of the effort on these tasks included providing direct ``On-site Support`` at Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), and Sandia National Laboratory Albuquerque (SNLA). They fabricated and delivered over 1,200 hohlraum mandrels and numerous other micromachined components to LLNL, LANL, and SNLA. They produced more than 1,300 glass and plastic target capsules for LLNL, LANL, SNLA, and the University of Rochester/Laboratory for Laser Energetics (UR/LLE). They also delivered nearly 2,000 various target foils and films for Naval Research Lab (NRL) and UR/LLE in FY98. This report describes these target fabrication activities and the target fabrication and characterization development activities that made the deliveries possible. During FY98, great progress was made by the GA/Schafer-UR/LLE-LANL team in the design, procurement, installation, and testing of the OMEGA Cryogenic Target System (OCTS) that will field cryogenic targets on OMEGA. The design phase was concluded for all components of the OCTS and all major components were procured and nearly all were fabricated. Many of the components were assembled and tested, and some have been shipped to UR/LLE. The ICF program is anticipating experiments at the OMEGA laser and the National Ignition Facility (NIF) which will require targets containing cryogenic layered D{sub 2} or deuterium-tritium (DT) fuel. They are part of the National Cryogenic Target Program and support experiments at LLNL and LANL to generate and characterize cryogenic layers for these targets. They also contributed cryogenic support and developed concepts for NIF cryogenic targets. This report summarizes and documents the technical progress made on these tasks.

  3. University of Rochester, Laboratory for Laser Energetics

    NASA Astrophysics Data System (ADS)

    1987-01-01

    In FY86 the Laboratory has produced a list of accomplishments in which it takes pride. LLE has met every laser-fusion program milestone to date in a program of research for direct-drive ultraviolet laser fusion originally formulated in 1981. LLE scientists authored or co-authored 135 scientific papers during 1985 to 1986. The collaborative experiments with NRL, LANL, and LLNL have led to a number of important ICF results. The cryogenic target system developed by KMS Fusion for LLE will be used in future high-density experiments on OMEGA to demonstrate the compression of thermonuclear fuel to 100 to 200 times that of solid (20 to 40 g/cm) in a test of the direct-drive concept, as noted in the National Academy of Sciences' report. The excellence of the advanced technology efforts at LLE is illustrated by the establishment of the Ultrafast Science Center by the Department of Defense through the Air Force Office of Scientific Research. Research in the Center will concentrate on bridging the gap between high-speed electronics and ultrafast optics by providing education, research, and development in areas critical to future communications and high-speed computer systems. The Laboratory for Laser Energetics continues its pioneering work on the interaction of intense radiation with matter. This includes inertial-fusion and advanced optical and optical electronics research; training people in the technology and applications of high-power, short-pulse lasers; and interacting with the scientific community, business, industry, and government to promote the growth of laser technology.

  4. Cleaning Process Versus Laser-Damage Threshold of Coated Optical Components

    SciTech Connect

    Rigatti, A.L.

    2005-03-31

    The cleaning of optical surfaces is important in the manufacture of high-laser-damage-threshold coatings, which are a key component on peak-power laser systems such as OMEGA located at the Laboratory for Laser Energetics (LLE). Since cleaning adds time, labor, and ultimately cost to the final coated component, this experiment was designed to determine the impact of different cleaning protocols on the measured laser-damage performance.

  5. Structural Optimization of Ghrelin Receptor Inverse Agonists to Improve Lipophilicity and Avoid Mechanism-Based CYP3A4 Inactivation.

    PubMed

    Takahashi, Bitoku; Funami, Hideaki; Shibata, Makoto; Maruoka, Hiroshi; Koyama, Makoto; Kanki, Satomi; Muto, Tsuyoshi

    2015-01-01

    Structural optimization of 2-aminonicotinamide derivatives as ghrelin receptor inverse agonists is reported. So as to avoid mechanism-based inactivation (MBI) of CYP3A4, 1,3-benzodioxol ring of the lead compound was modified. Improvement of the main activity and lipophilicity was achieved simultaneously, leading to compound 18a, which showed high lipophilic ligand efficiency (LLE) and low MBI activity. PMID:26423040

  6. Loss of lifetime due to radiation exposure-averaging problems.

    PubMed

    Raicević, J J; Merkle, M; Ehrhardt, J; Ninković, M M

    1997-04-01

    A new method is presented for assessing a years of life lost (YLL) due to stochastic effects caused by the exposure to ionizing radiation. The widely accepted method from the literature uses a ratio of means of two quantities, defining in fact the loss of life as a derived quantity. We start from the real stochastic nature of the quantity (YLL), which enables us to obtain its mean values in a consistent way, using the standard averaging procedures, based on the corresponding joint probability density functions needed in this problem. Our method is mathematically different and produces lower values of average YLL. In this paper we also found certain similarities with the concept of loss of life expectancy among exposure induced deaths (LLE-EID), which is accepted in the recently published UNSCEAR report, where the same quantity is defined as years of life lost per radiation induced case (YLC). Using the same data base, the YLL and the LLE-EID are calculated and compared for the simplest exposure case-the discrete exposure at age a. It is found that LLE-EID overestimates the YLL, and that the magnitude of this overestimation reaches more than 15%, which depends on the effect under consideration. PMID:9119679

  7. Determination of fluoride in toothpaste using headspace solid-phase microextraction and gas chromatography-flame ionization detection.

    PubMed

    Wejnerowska, Grazyna; Karczmarek, Anna; Gaca, Jerzy

    2007-05-25

    A new method for determination of fluoride in toothpaste employing the headspace solid-phase microextraction (HS-SPME) followed by gas chromatography/flame ionization detection (GC/FID) has been proposed. It is a development of the method for determination of fluoride using trimethylchlorosilane (TMCS) as the derivatization reagent to form trimethylfluorosilane (TMFS), with the liquid/liquid extraction (LLE) step replaced by HS-SPME. To introduce the latter, it was necessary to determine the conditions of the reaction and to optimize the two stages of the SPME procedure: extraction and desorption. The parameters of the SPME analysis using carboxen/polydimethylsiloxane (CAR/PDMS) fiber were defined and compared with the corresponding ones for the LLE method, used as a reference. Also, these two methods were compared with respect to their linearity, precision, and accuracy. Results from toothpaste analyses using these two methods were highly correlated, indicating the potential to use the SPME extraction as an inexpensive and solventfree alternative to the LLE method. PMID:17070826

  8. Identification and quantification analysis of nonlinear dynamics properties of combustion instability in a diesel engine

    NASA Astrophysics Data System (ADS)

    Yang, Li-Ping; Ding, Shun-Liang; Litak, Grzegorz; Song, En-Zhe; Ma, Xiu-Zhen

    2015-01-01

    The cycling combustion instabilities in a diesel engine have been analyzed based on chaos theory. The objective was to investigate the dynamical characteristics of combustion in diesel engine. In this study, experiments were performed under the entire operating range of a diesel engine (the engine speed was changed from 600 to 1400 rpm and the engine load rate was from 0% to 100%), and acquired real-time series of in-cylinder combustion pressure using a piezoelectric transducer installed on the cylinder head. Several methods were applied to identify and quantitatively analyze the combustion process complexity in the diesel engine including delay-coordinate embedding, recurrence plot (RP), Recurrence Quantification Analysis, correlation dimension (CD), and the largest Lyapunov exponent (LLE) estimation. The results show that the combustion process exhibits some determinism. If LLE is positive, then the combustion system has a fractal dimension and CD is no more than 1.6 and within the diesel engine operating range. We have concluded that the combustion system of diesel engine is a low-dimensional chaotic system and the maximum values of CD and LLE occur at the lowest engine speed and load. This means that combustion system is more complex and sensitive to initial conditions and that poor combustion quality leads to the decrease of fuel economy and the increase of exhaust emissions.

  9. A simultaneous extraction method for organophosphate, pyrethroid, and neonicotinoid insecticides in aqueous samples.

    PubMed

    de Perre, Chloé; Whiting, Sara A; Lydy, Michael J

    2015-05-01

    A method was developed for the extraction and analysis of 2 organophosphate, 8 pyrethroid, and 5 neonicotinoid insecticides from the same water sample. A salted liquid-liquid extraction (LLE) was optimized with a solid-phase extraction (SPE) step that separated the organophosphates (OPs) and pyrethroids from the neonicotinoids. Factors that were optimized included volume of solvent and amount of salt used in the LLE, homogenization time for the LLE, and type and volume of eluting solvent used for the SPE. The OPs and pyrethroids were quantified using gas chromatography-mass spectrometry, and the neonicotinoids were quantified using liquid chromatography-diode array detector. Results showed that the optimized method was accurate, precise, reproducible, and robust; recoveries in river water spiked with 100 ng L(-1) of each of the insecticides were all between 86 and 114 % with RSDs between 2 and 8 %. The method was also sensitive with method detection limits ranging from 0.1 to 27.2 ng L(-1) depending on compounds and matrices. The optimized method was thus appropriate for the simultaneous extraction of 15 widely applied insecticides from three different classes and was shown to provide valuable information on their environmental fate from field-collected aqueous samples. PMID:25608617

  10. Influence of Salts on the Partitioning of 5-Hydroxymethylfurfural in Water/MIBK.

    PubMed

    Mohammad, Sultan; Held, Christoph; Altuntepe, Emrah; Köse, Tülay; Sadowski, Gabriele

    2016-04-28

    This study investigates the influence of electrolytes on the performance of extracting 5-hydroxymethylfurfural (HMF) from aqueous media using methyl isobutyl ketone (MIBK). For that purpose, liquid-liquid phase equilibria (LLE) of quaternary systems containing HMF, water, MIBK and salts were measured at atmospheric pressure and 298.15 K. The salts under investigation were composed of one of the anions NO(3-), SO4(2-), Cl(-), or CH3COO(-) and of one of the alkali cations Li(+), Na(+), or K(+). On the basis of these LLE data, the partition coefficient of HMF between the aqueous and the MIBK phase KHMF was determined. It could be shown that KHMF significantly depends on the kind and concentration of the added salt. Weak electrolytes (e.g., sulfates, acetates) caused salting-out, whereas nitrates caused salting-in of HMF to the aqueous phase. Unexpectedly, LiCl caused salting-out at low LiCl concentrations and salting-in at LiCl concentrations higher than 3 mol/kgH2O. The model electrolyte perturbed-chain SAFT (ePC-SAFT) was used to predict the salt influence on the LLE in the quaternary systems water/MIBK/HMF/salt in good agreement with the experimental data. On the basis of ePC-SAFT, it could be concluded that the different salting-out/salting-in behavior of the various salts is mainly caused by their different tendency to form ion pairs in aqueous solutions. PMID:27027570

  11. Automated GC-MS Determination of Δ9-Tetrahydrocannabinol, Cannabinol and Cannabidiol in Hair.

    PubMed

    Heinl, Sonja; Lerch, Oliver; Erdmann, Freidoon

    2016-09-01

    The determination of Δ(9)-tetrahydrocannabinol (THC), cannabinol (CBN) and cannabidiol (CBD) in hair is a major routine task in forensic laboratories worldwide. A comprehensively automated liquid-liquid extraction (LLE) method has been developed. The automation was carried out by an x-y-z sample robot equipped with modules capable of shaking, centrifugation and solvent evaporation. It comprises digestion of hair in sodium hydroxide solution, LLE, extract evaporation, reconstitution in silylation reagent, inlet derivatization and GC-MS analysis. Method validation guidelines of the Society for Toxicological and Forensic Chemistry were fulfilled. The limit of quantification (LOQ) was 0.01 ng/mg for THC, 0.06 ng/mg for CBN and 0.03 ng/mg for CBD. This is below the required LOQ for THC (0.02 ng/mg) in medical psychological assessments in Germany. Also it is far below the required LOQ of the Society of Hair Testing of 0.1 ng/mg for THC. Four-round robin tests were passed successfully and several post- and ante-mortem samples were analyzed. To date the method is routinely employed at the Institute of Legal Medicine in Giessen, Germany. To the best of our knowledge, this is the first publication on a comprehensively automated classical LLE workflow in the field of hair analysis. PMID:27344041

  12. Late Language Emergence at 24 Months: An Epidemiological Study of Prevalence, Predictors, and Covariates

    PubMed Central

    Zubrick, Stephen R.; Taylor, Catherine L.; Rice, Mabel L.

    2012-01-01

    Purpose The primary objectives of this study were to determine the prevalence of late language emergence (LLE) and to investigate the predictive status of maternal, family, and child variables. Method This is a prospective cohort study of 1766 epidemiologically ascertained twenty-four-month singleton children. The framework was an ecological model of child development, encompassing a wide range of maternal, family, and child variables. Data were obtained using postal questionnaire. Item analyses of the 6-item Ages and Stages Questionnaire (ASQ) Communication Scale yielded a composite score encompassing comprehension as well as production items. One standard deviation below the mean yielded good separation of affected from unaffected children. Analyses of bivariate relationships with maternal, family, and child variables were carried out, followed by multivariate logistic regression to predict LLE group membership. Results 13.4% of the sample showed late language emergence via the ASQ criterion; 19.1% using a single item “combining words.” Risk for LLE at 24 months was not associated with particular strata of parental educational levels, socioeconomic resources, parental mental health, parenting practices or family functioning. Significant predictors included familial history of late language emergence, male gender and early neurobiological growth. Covariates included psychosocial indicators. Conclusion Results are congruent with models of language emergence and impairment that posit a strong role for neurobiological and genetic mechanisms of onset that operate across a wide variation in maternal and family characteristics. PMID:18055773

  13. Determination of tamoxifen and its metabolites using micelle to solvent stacking in nonaqueous capillary electrophoresis.

    PubMed

    Thang, Lee Yien; See, Hong Heng; Quirino, Joselito P

    2016-05-01

    Micelle to solvent stacking was implemented for the recently established NACE-C(4) D method to determine tamoxifen and its metabolites in standard samples and human plasma of breast cancer patients. For stacking, the standard samples and extract after liquid-liquid extraction (LLE) were prepared in methanol and the resulting sample solution was pressure injected after a micellar plug of SDS. Factors that affected the stacking such as SDS concentration, micelle, and sample plug length were examined. The sensitivity enhancement factor (peak height from stacking/peak height from typical injection of sample in BGE) was 15-22. The method detection limits with LLE were in the range of 5-10 ng/mL, which was lower than the established method (where the LLE extract was also prepared in methanol) with reported method detection limits of 25-40 ng/mL. The intraday and interday repeatability were in the range of 1.0-3.4% and 3.8-6.5%, respectively. PMID:26873060

  14. Pattern Freezing Process Free Litho-Litho-Etch Double Patterning

    NASA Astrophysics Data System (ADS)

    Ando, Tomoyuki; Takeshita, Masaru; Takasu, Ryoichi; Yoshii, Yoshihiro; Iwashita, Jun; Matsumaru, Shogo; Abe, Sho; Iwai, Takeshi

    2009-06-01

    Double patterning technology based on existing ArF immersion lithography is considered as the most viable option for complementary metal oxide semiconductor (CMOS) node of 32 nm and below. Most of double patterning approaches previously described requires intermediate processing step such as hard mask etching, spacer material deposition, and resist pattern freezing. The requirement of these additional steps is now leading way to requests for throughput reduction and low cost for production for double patterning technology applications. In this paper, litho-litho-etch (LLE) double patterning without any intermediate processing steps is investigated to achieve narrow pitch resist imaging. The LLE options examined in this work are combinations of positive tone-negative tone and positive tone-positive tone photoresist double patterning process. These are the alternative processes in pattern freezing process free LLE double patterning. The goals of this work are to determine witch of these approaches is the most viable for future application and to confirm the patterning potential for 32 nm and below half pitch resist imaging.

  15. Molecular Recognition of the Catalytic Zinc(II) Ion in MMP-13: Structure-Based Evolution of an Allosteric Inhibitor to Dual Binding Mode Inhibitors with Improved Lipophilic Ligand Efficiencies

    PubMed Central

    Fischer, Thomas; Riedl, Rainer

    2016-01-01

    Matrix metalloproteinases (MMPs) are a class of zinc dependent endopeptidases which play a crucial role in a multitude of severe diseases such as cancer and osteoarthritis. We employed MMP-13 as the target enzyme for the structure-based design and synthesis of inhibitors able to recognize the catalytic zinc ion in addition to an allosteric binding site in order to increase the affinity of the ligand. Guided by molecular modeling, we optimized an initial allosteric inhibitor by addition of linker fragments and weak zinc binders for recognition of the catalytic center. Furthermore we improved the lipophilic ligand efficiency (LLE) of the initial inhibitor by adding appropriate zinc binding fragments to lower the clogP values of the inhibitors, while maintaining their potency. All synthesized inhibitors showed elevated affinity compared to the initial hit, also most of the novel inhibitors displayed better LLE. Derivatives with carboxylic acids as the zinc binding fragments turned out to be the most potent inhibitors (compound 3 (ZHAWOC5077): IC50 = 134 nM) whereas acyl sulfonamides showed the best lipophilic ligand efficiencies (compound 18 (ZHAWOC5135): LLE = 2.91). PMID:26938528

  16. Characteristic Extraction of Mental Disease Patients by Nonlinear Analysis of Plethysmograms

    NASA Astrophysics Data System (ADS)

    Hu, Yuyu; Wang, Wenbiao; Suzuki, Takashi; Oyama-Higa, Mayumi

    2011-06-01

    We measured the pulse waves of 196 mentally ill patients and 113 healthy students. Using heartbeat changes, we calculated the values of their sympathetic nerves, parasympathetic nerves, and autonomic nerve balance. In addition, we calculated the largest Lyapunov exponents (LLE) by non-linear analysis of plethysmograms. Values were analyzed by group. The results revealed a significant relationship between LLE and the autonomic nerve balance. The sympathetic nerve values in the patient group were significantly higher than those in the student group, whereas the LLE values were significantly lower. Furthermore, we illustrated the dynamic change in the results for single participants over several testing times. The measurement of pulse waves is easy and economical and does not put a strain on the subject. Additionally, these values can provide information that is more accurate than medical examination obtained from an interview. Our study contributed to the existing methodology in this field, and future data collection and measurement will be carried out. We hope that our study will be useful for neurologists and psychotherapists in their detection and treatment of mental illness.

  17. Approximate Orthogonal Sparse Embedding for Dimensionality Reduction.

    PubMed

    Lai, Zhihui; Wong, Wai Keung; Xu, Yong; Yang, Jian; Zhang, David

    2016-04-01

    Locally linear embedding (LLE) is one of the most well-known manifold learning methods. As the representative linear extension of LLE, orthogonal neighborhood preserving projection (ONPP) has attracted widespread attention in the field of dimensionality reduction. In this paper, a unified sparse learning framework is proposed by introducing the sparsity or L1-norm learning, which further extends the LLE-based methods to sparse cases. Theoretical connections between the ONPP and the proposed sparse linear embedding are discovered. The optimal sparse embeddings derived from the proposed framework can be computed by iterating the modified elastic net and singular value decomposition. We also show that the proposed model can be viewed as a general model for sparse linear and nonlinear (kernel) subspace learning. Based on this general model, sparse kernel embedding is also proposed for nonlinear sparse feature extraction. Extensive experiments on five databases demonstrate that the proposed sparse learning framework performs better than the existing subspace learning algorithm, particularly in the cases of small sample sizes. PMID:25955995

  18. 1991 Summer research program for high school juniors at the University of Rochester`s Laboratory for Laser Energetics. Student research reports

    SciTech Connect

    Not Available

    1991-09-01

    Ten students participated in the 1991 summer high school student research program at the University of Rochester`s Laboratory for Laser Energetics (LLE). The participants spent 8 weeks working and learning at LLE. They spent most of their time working on individual research projects. Each student was assigned a project, upon which he/she worked under the direct supervision of one of the staff members of the laboratory. The students, their high schools, and their projects are listed in Table 1. The program culminated in oral and written reports describing their work. The oral reports were presented at a symposium on 23 August 1991, at which the student`s parents and teachers and members of the LLE staff were present. The written reports are collected in this volume. The titles of the works are UV alignment table; neutron yields can be measured by using the relative gain of a photomultiplier tube; scattering in isotropic and anisotropic media; a better approximation of the diffusion equation; use of the SLAC code to produce a photoemissive electrostatic electron gun; spatial resolution deteriorates with increasing film exposure; analysis of refractive image distortion; making of pinholes for x-ray pinhole cameras; does perturbation theory accurately describe multiphoton ionization? and wave front analysis using shearing interferometry.

  19. 1991 Summer research program for high school juniors at the University of Rochester's Laboratory for Laser Energetics

    SciTech Connect

    Meyerhofer, David D.

    1991-09-01

    Ten students participated in the 1991 summer high school student research program at the University of Rochester's Laboratory for Laser Energetics (LLE). The participants spent 8 weeks working and learning at LLE. They spent most of their time working on individual research projects. Each student was assigned a project, upon which he/she worked under the direct supervision of one of the staff members of the laboratory. The students, their high schools, and their projects are listed in Table 1. The program culminated in oral and written reports describing their work. The oral reports were presented at a symposium on 23 August 1991, at which the student's parents and teachers and members of the LLE staff were present. The written reports are collected in this volume. The titles of the works are UV alignment table; neutron yields can be measured by using the relative gain of a photomultiplier tube; scattering in isotropic and anisotropic media; a better approximation of the diffusion equation; use of the SLAC code to produce a photoemissive electrostatic electron gun; spatial resolution deteriorates with increasing film exposure; analysis of refractive image distortion; making of pinholes for x-ray pinhole cameras; does perturbation theory accurately describe multiphoton ionization and wave front analysis using shearing interferometry.

  20. Identification and quantification analysis of nonlinear dynamics properties of combustion instability in a diesel engine

    SciTech Connect

    Yang, Li-Ping Ding, Shun-Liang; Song, En-Zhe; Ma, Xiu-Zhen; Litak, Grzegorz

    2015-01-15

    The cycling combustion instabilities in a diesel engine have been analyzed based on chaos theory. The objective was to investigate the dynamical characteristics of combustion in diesel engine. In this study, experiments were performed under the entire operating range of a diesel engine (the engine speed was changed from 600 to 1400 rpm and the engine load rate was from 0% to 100%), and acquired real-time series of in-cylinder combustion pressure using a piezoelectric transducer installed on the cylinder head. Several methods were applied to identify and quantitatively analyze the combustion process complexity in the diesel engine including delay-coordinate embedding, recurrence plot (RP), Recurrence Quantification Analysis, correlation dimension (CD), and the largest Lyapunov exponent (LLE) estimation. The results show that the combustion process exhibits some determinism. If LLE is positive, then the combustion system has a fractal dimension and CD is no more than 1.6 and within the diesel engine operating range. We have concluded that the combustion system of diesel engine is a low-dimensional chaotic system and the maximum values of CD and LLE occur at the lowest engine speed and load. This means that combustion system is more complex and sensitive to initial conditions and that poor combustion quality leads to the decrease of fuel economy and the increase of exhaust emissions.

  1. Detection of sulfonamide drug in urine using liquid-liquid extraction and surface-enhanced Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Markina, Natalia E.; Shalabay, Victoria V.; Zakharevich, Andrey M.; Markin, Alexey V.

    2016-04-01

    In this article we have applied liquid-liquid extraction (LLE) as a sample preparation technique for detection of sulfadimethoxine (one of sulfonamide drugs) in urine using surface-enhanced Raman spectroscopy (SERS). SERS substrate based on silver nanoparticles has been prepared by citrate reduction of silver nitrate. Obtained calibration curve (SERS intensity vs. sulfadimethoxine concentration) has been used for detection of sulfadimethoxine in human urine samples artificially contaminated by sulfadimethoxine. Three different solvents (ethyl acetate, diethyl ether, chloroform) have been used for LLE performance tests. Chloroform being found as the most effective one based on calculation of recoveries after SERS measurements. Thus we would like to propose fast (less than 20 minutes), simple and sensitive (detection limit up to 1 μg/ml) test for detecting sulfa drugs in urine using a combination of SERS with LLE with sample volume as low as 100 μL. Such test can be applied for evaluation of the degree of drug extraction from human body and half-life of such drug applied in the course of therapeutic treatments of certain diseases.

  2. Analytical Treatment of the Metabolic Effects of Isocaloric Stimulant on Heart Rate Variability as Measured by Electrocardiograph

    NASA Astrophysics Data System (ADS)

    Taffe, Lauren Rachelle

    Heart Rate variability (HRV) is measured during a period that includes ingestion and digestion of 900 kilogram calories of carbohydrate and fat beverages on two separate occasions. Autoregressive (AR) analysis, Poincare Plot Analysis (PPA), Detrended Fluctuation Analysis (DFA), and the Largest Lyapunov Exponent (LLE) highlights variations in the linear and non-linear indices with respect to time. DFA indices indicated that all individuals were healthy (α≈1). In addition, an overall increase of α over the 3-hour observation time shows increased sympathetic intonation. Body Mass Index (BMI) influences on HRV were found. Over short time scales, DFA's α 1 index suggests the potentiality for future patho-physiological risk in those with high BMI>25. Over longer time scales, α2 has no significant differentiation among different BMI groups. The application of k-means cluster analysis revealed a connection to BMI when α and α 1 /α2 parameters were used. We believe that the LLE indicates an increased stability during digestion of the hypercaloric beverages. Groups with BMI>25 have smaller LLE, on average, than BMI≤ 25. This does substantiate the AR, Poincare, and DFA analyses of groups with higher BMI having less sympathetic increase when compared to lower BMI groups due to caloric metabolism.

  3. THREE-DIMENSIONAL CHARACTERIZATION OF CRYOGENIC TARGET ICE LAYERS USING MULTIPLE SHADOWGRAPH VIEWS

    SciTech Connect

    Edgell, D.H.; Craxton, R.S.; Elasky, L.M.; Harding, D.R.; Iwan, L.S.; Keck, R.L.; Lund, L.D.; Verbridge, S.J.; WIttman, M.D.; Warrick, A.; Brown, T.; Seka, W.

    2006-05-17

    Backlit optical shadowgraphy is the primary diagnostic for D2 ice layer characterization of cryogenic targets for the OMEGA Laser System at the Laboratory for Laser Energetics (LLE). Reflection and refraction of light passing through the ice layer produce characteristic rings. The position of the most prominent of the shadowgraph rings, known as the bright ring, can be resolved to ~0.1-pixel rms, corresponding to about 0.12 um for typical LLE target shadowgraphs. Measurement of the bright ring position in conjuction with ray-trace model predictions determines the ice layer thickness and the Fourier-mode spectrum of the ice roughness for that view. The LLE target characterization stations use two camera angles and target rotation to record target shadowgraphs from many different views. Combining these views allows construction of a 3-D ice layer representation, an estimation of the global surface roughness, and a determination of a Legendre-mode spectrum suitable for implosion modeling. The standard operating procedure is to construct a 3-D ice layer representation using the analysis of 48 separate shadowgraphic views. The 3-D ice surface is then decomposed in terms of spherical harmonics, allowing the determination of low-mode number (l < 8 to 10) elements of a Legendre-mode power spectrum. High-mode number elements of the Legendre power spectrum are determined by mapping the Fourier-mode power spectrum averaged over all views.

  4. Use of domesticated pigs by Mesolithic hunter-gatherers in northwestern Europe

    PubMed Central

    Krause-Kyora, Ben; Makarewicz, Cheryl; Evin, Allowen; Flink, Linus Girdland; Dobney, Keith; Larson, Greger; Hartz, Sönke; Schreiber, Stefan; von Carnap-Bornheim, Claus; von Wurmb-Schwark, Nicole; Nebel, Almut

    2013-01-01

    Mesolithic populations throughout Europe used diverse resource exploitation strategies that focused heavily on collecting and hunting wild prey. Between 5500 and 4200 cal BC, agriculturalists migrated into northwestern Europe bringing a suite of Neolithic technologies including domesticated animals. Here we investigate to what extent Mesolithic Ertebølle communities in northern Germany had access to domestic pigs, possibly through contact with neighbouring Neolithic agricultural groups. We employ a multidisciplinary approach, applying sequencing of ancient mitochondrial and nuclear DNA (coat colour-coding gene MC1R) as well as traditional and geometric morphometric (molar size and shape) analyses in Sus specimens from 17 Neolithic and Ertebølle sites. Our data from 63 ancient pig specimens show that Ertebølle hunter-gatherers acquired domestic pigs of varying size and coat colour that had both Near Eastern and European mitochondrial DNA ancestry. Our results also reveal that domestic pigs were present in the region ~500 years earlier than previously demonstrated. PMID:23982268

  5. Sustainable efficient way for opioid peptide LVV-h7 preparation from enzymatic proteolysis in a microfluidic-based reaction-extraction process with solvent recycling.

    PubMed

    Elagli, Adil; Belhacene, Kalim; Dhulster, Pascal; Froidevaux, Renato

    2016-05-01

    LVV-h7 (LVVYPWTQFR) is a bioactive peptide that can be obtained from blood as waste of food industry, more precisely from hemoglobin hydrolysis by pepsin. This opioid peptide belongs to the hemorphins family and have strong physiological effects that bring its use in pharmaceutics and various therapeutic treatments attractive, in particular for substituting its costly chemically synthetized analogous. Hemoglobin hydrolysis by pepsin generates a huge variety of peptides among whose LVV-h7 can be purified by liquid-liquid extraction (LLE). Herein, selective preparation of this peptide is proposed by a microfluidic-based continuous reaction-separation process. Hemoglobin hydrolysis in microreactor was firstly coupled to LVV-h7 LLE in octan-1-ol and then coupled to LVV-h7 back LLE in acidic water. This continuous process allowed to prepare pure LVV-h7, as confirmed by liquid chromatography and mass spectrometry. The microfluidic circuit also allowed octan-1-ol recycling in a closed loop, making this method more sustainable than similar biphasic batch process. PMID:26998857

  6. Recent advances in sample preparation techniques for effective bioanalytical methods.

    PubMed

    Kole, Prashant Laxman; Venkatesh, Gantala; Kotecha, Jignesh; Sheshala, Ravi

    2011-01-01

    This paper reviews the recent developments in bioanalysis sample preparation techniques and gives an update on basic principles, theory, applications and possibilities for automation, and a comparative discussion on the advantages and limitation of each technique. Conventional liquid-liquid extraction (LLE), protein precipitation (PP) and solid-phase extraction (SPE) techniques are now been considered as methods of the past. The last decade has witnessed a rapid development of novel sample preparation techniques in bioanalysis. Developments in SPE techniques such as selective sorbents and in the overall approach to SPE, such as hybrid SPE and molecularly imprinted polymer SPE, have been addressed. Considerable literature has been published in the area of solid-phase micro-extraction and its different versions, e.g. stir bar sorptive extraction, and their application in the development of selective and sensitive bioanalytical methods. Techniques such as dispersive solid-phase extraction, disposable pipette extraction and micro-extraction by packed sorbent offer a variety of extraction phases and provide unique advantages to bioanalytical methods. On-line SPE utilizing column-switching techniques is rapidly gaining acceptance in bioanalytical applications. PP sample preparation techniques such as PP filter plates/tubes offer many advantages like removal of phospholipids and proteins in plasma/serum. Newer approaches to conventional LLE techniques (salting-out LLE) are also covered in this review article. PMID:21154887

  7. Molecular Recognition of the Catalytic Zinc(II) Ion in MMP-13: Structure-Based Evolution of an Allosteric Inhibitor to Dual Binding Mode Inhibitors with Improved Lipophilic Ligand Efficiencies.

    PubMed

    Fischer, Thomas; Riedl, Rainer

    2016-01-01

    Matrix metalloproteinases (MMPs) are a class of zinc dependent endopeptidases which play a crucial role in a multitude of severe diseases such as cancer and osteoarthritis. We employed MMP-13 as the target enzyme for the structure-based design and synthesis of inhibitors able to recognize the catalytic zinc ion in addition to an allosteric binding site in order to increase the affinity of the ligand. Guided by molecular modeling, we optimized an initial allosteric inhibitor by addition of linker fragments and weak zinc binders for recognition of the catalytic center. Furthermore we improved the lipophilic ligand efficiency (LLE) of the initial inhibitor by adding appropriate zinc binding fragments to lower the clogP values of the inhibitors, while maintaining their potency. All synthesized inhibitors showed elevated affinity compared to the initial hit, also most of the novel inhibitors displayed better LLE. Derivatives with carboxylic acids as the zinc binding fragments turned out to be the most potent inhibitors (compound 3 (ZHAWOC5077): IC50 = 134 nM) whereas acyl sulfonamides showed the best lipophilic ligand efficiencies (compound 18 (ZHAWOC5135): LLE = 2.91). PMID:26938528

  8. Progress towards polar-drive ignition for the NIF

    NASA Astrophysics Data System (ADS)

    McCrory, R. L.; Betti, R.; Boehly, T. R.; Casey, D. T.; Collins, T. J. B.; Craxton, R. S.; Delettrez, J. A.; Edgell, D. H.; Epstein, R.; Frenje, J. A.; Froula, D. H.; Gatu-Johnson, M.; Glebov, V. Yu.; Goncharov, V. N.; Harding, D. R.; Hohenberger, M.; Hu, S. X.; Igumenshchev, I. V.; Kessler, T. J.; Knauer, J. P.; Li, C. K.; Marozas, J. A.; Marshall, F. J.; McKenty, P. W.; Meyerhofer, D. D.; Michel, D. T.; Myatt, J. F.; Nilson, P. M.; Padalino, S. J.; Petrasso, R. D.; Radha, P. B.; Regan, S. P.; Sangster, T. C.; Séguin, F. H.; Seka, W.; Short, R. W.; Shvydky, A.; Skupsky, S.; Soures, J. M.; Stoeckl, C.; Theobald, W.; Yaakobi, B.; Zuegel, J. D.

    2013-11-01

    The University of Rochester's Laboratory for Laser Energetics (LLE) performs direct-drive inertial confinement fusion (ICF) research. LLE's Omega Laser Facility is used to study direct-drive ICF ignition concepts, developing an understanding of the underlying physics that feeds into the design of ignition targets for the National Ignition Facility (NIF). The baseline symmetric-illumination, direct-drive-ignition target design consists of a 1.5 MJ multiple-picket laser pulse that generates four shock waves (similar to the NIF baseline indirect-drive design) and is predicted to produce a one-dimensional (1D) gain of 48. LLE has developed the polar-drive (PD) illumination concept (for NIF beams in the x-ray-drive configuration) to allow the pursuit of direct-drive ignition without significant reconfiguration of the beam paths on the NIF. Some less-invasive changes in the NIF infrastructure will be required, including new phase plates, polarization rotators, and a PD-specific beam-smoothing front end. A suite of PD ignition designs with implosion velocities from 3.5 to 4.3 × 107 cm s-1 are predicted to have significant 2D gains (Collins et al 2012 Bull. Am. Phys. Soc. 57 155). Verification of the physics basis of these simulations is a major thrust of direct-drive implosion experiments on both OMEGA and the NIF. Many physics issues are being examined with symmetric beam irradiation on OMEGA, varying the implosion parameters over a wide region of design space. Cryogenic deuterium-tritium target experiments with symmetric irradiation have produced areal densities of ˜0.3 g cm-2, ion temperatures over 3 keV, and neutron yields in excess of 20% of the ‘clean’ 1D predicted value. The inferred Lawson criterion figure of merit (Betti R. et al 2010 Phys. Plasmas 17 058102) has increased from 1.7 atm s (IAEA 2010) to 2.6 atm s.

  9. Techno-economic analysis for incorporating a liquid-liquid extraction system to remove acetic acid into a proposed commercial scale biorefinery.

    PubMed

    Aghazadeh, Mahdieh; Engelberth, Abigail S

    2016-07-01

    Mitigating the effect of fermentation inhibitors in bioethanol plants can have a great positive impact on the economy of this industry. Liquid-liquid extraction (LLE) using ethyl acetate is able to remove fermentation inhibitors-chiefly, acetic acid-from an aqueous solution used to produce bioethanol. The fermentation broth resulting from LLE has higher performance for ethanol yield and its production rate. Previous techno-economic analyses focused on second-generation biofuel production did not address the impact of removing the fermentation inhibitors on the economic performance of the biorefinery. A comprehensive analysis of applying a separation system to mitigate the fermentation inhibition effect and to provide an analysis on the economic impact of removal of acetic acid from corn stover hydrolysate on the overall revenue of the biorefinery is necessary. This study examines the pros and cons associated with implementing LLE column along with the solvent recovery system into a commercial scale bioethanol plant. Using details from the NREL-developed model of corn stover biorefinery, the capital costs associated with the equipment and the operating cost for the use of solvent were estimated and the results were compared with the profit gain due to higher ethanol production. Results indicate that the additional capital will add 1% to the total capital and manufacturing cost will increase by 5.9%. The benefit arises from the higher ethanol production rate and yield as a consequence of inhibitor extraction and results in a $0.35 per gallon reduction in the minimum ethanol selling price (MESP). © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:971-977, 2016. PMID:27390294

  10. Critical development by design of a rugged HPLC-MS/MS method for direct determination of ibuprofen enantiomers in human plasma.

    PubMed

    Nakov, Natalija; Petkovska, Rumenka; Ugrinova, Liljana; Kavrakovski, Zoran; Dimitrovska, Aneta; Svinarov, Dobrin

    2015-06-15

    Development and validation of a HPLC-MS/MS method for direct determination of R- and S-ibuprofen (Ibu) in human plasma without a need of derivatization or other complexities such as postcolumn infusion of solvents or reagents was performed. Critical steps were investigated during method development using experimental design to achieve a reliable and rugged assay. The LC-MS/MS separation of R-Ibu and S-Ibu was obtained on Lux Cellulose chiral column utilizing 0.1% (v/v) acetic acid in mixture of methanol and water (90:10%, v/v) as a mobile phase. Two types of extraction procedure for Ibu and Ketoprofen (internal standard, IS) were optimized using Full factorial 3(2) design (LLE) and D-Optimal Experimental Design (SPE). Excellent recovery values, 80% (mean) and 95% (mean) for LLE and SPE respectively, were obtained using 50μL plasma. The matrix effect was assessed for both of the extraction procedures, including hyperlipidaemic and haemolyzed plasma. The extensive investigation of matrix effect showed that LLE yields cleaner extracts than the SPE. The result of the investigation of in vitro interconversion of R-Ibu and S-Ibu showed that it does not occur under the influence of pH, temperature, and in the overall analytical procedure. The validation data, adhered to EMA guideline for validation of bioanalytical methods, showed that the proposed method provides accurate and reproducible results in range of 0.1-50mg/L with a lower limit of detection of 0.02mg/L. The applicability of the method was demonstrated through determination of R-Ibu and S-Ibu in human plasma after oral administration of 400mg rac-Ibu. PMID:25958322

  11. A different approach to evaluating health effects from radiation exposure

    SciTech Connect

    Bond, V.P.; Sondhaus, C.A.; Feinendegen, L.E.

    1988-01-01

    Absorbed dose D is shown to be a composite variable, the product of the fraction of cells hit (I/sub H/) and the mean /open quotes/dose/close quotes/ (hit size) /ovr z/ to those cells. D is suitable for use with high level (HLE) to radiation and its resulting acute organ effects because, since I/sub H/ = 1.0, D approximates closely enough the mean energy density in the cell as well as in the organ. However, with low-level exposure (LLE) to radiation and its consequent probability of cancer induction from a single cell, stochastic delivery of energy to cells results in a wide distribution of hit sizes z, and the expected mean value, /ovr z/, is constant with exposure. Thus, with LLE, only I/sub H/ varies with D so that the apparent proportionality between /open quotes/dose/close quotes/ and the fraction of cells transformed is misleading. This proportionality therefore does not mean that any (cell) dose, no matter how small, can be lethal. Rather, it means that, in the exposure of a population of individual organisms consisting of the constituent relevant cells, there is a small probabililty of particle-cell interactions which transfer energy. The probability of a cell transforming and initiating a cancer can only be greater than zero if the hit size (/open quotes/dose of energy/close quotes/) to the cell is large enough. Otherwise stated, if the /open quotes/dose/close quotes/ is defined at the proper level of biological organization, namely, the cell and not the organ, only a large dose z to that cell is effective. The above precepts are utilized to develop a drastically different approach to evaluation oif risk from LLE, that holds promise of obviating any requirement for the components of the present system: absorbed organ dose, LET, a standard radiation, REB(Q), dose equivalent and rem. 12 refs., 11 figs.

  12. Development of a low-density polyethylene-containing passive sampler for measuring dissolved hydrophobic organic compounds in open waters.

    PubMed

    Bao, Lian-Jun; Xu, Shi-Ping; Liang, Yan; Zeng, Eddy Y

    2012-05-01

    A passive water sampler with low-density polyethylene (LDPE) as the sorbent phase was built and field-tested for sensing freely dissolved concentrations of hydrophobic organic compounds (HOCs) in fresh and coastal water. Based on the measured LDPE-water partition coefficients (K(pew)) of 12 polycyclic aromatic hydrocarbons (PAHs) and dichlorodiphenyltrichloroethane (DDT) and its seven metabolites, the detection limits with the passive sampler containing 10-g LDPE ranged from 0.04 to 56.9 pg/L in the equilibrium sampling mode. Furthermore, the utility of the passive sampler in measuring dissolved HOC concentrations in open waters was examined through a comparison with solid-phase extraction combined with liquid-liquid extraction (SPE-LLE) and poly(dimethyl)siloxane (PDMS) coated fiber samplers. The total concentrations of PAHs (3.8-16 ng/L) obtained by the passive sampler were lower than those (87.7-115.5 ng/L) obtained through SPE-LLE. This large difference was probably attributable to slower water exchange in and out of the passive sampler as time progressed because of blockage by algae in eutrophia reservoirs and high dissolved organic carbon contents resulting in higher-than-expected PAH concentrations by SPE-LLE. Furthermore, the concentrations and compositional profiles of DDXs (sum of p,p'-DDT, p,p'-DDD, p,p'-DDE, o,p'-DDT, o,p'-DDD, o,p'-DDE, and p,p'-DDMU) at site A obtained by the passive sampler agreed with the results obtained with the PDMS-coated fibers, suggesting that the passive sampler was able to reasonably quantify dissolved HOCs in seawater. PMID:22388779

  13. Effects of hypercapnia and hypocapnia on ventilatory variability and the chaotic dynamics of ventilatory flow in humans.

    PubMed

    Fiamma, Marie-Noëlle; Straus, Christian; Thibault, Sylvain; Wysocki, Marc; Baconnier, Pierre; Similowski, Thomas

    2007-05-01

    In humans, lung ventilation exhibits breath-to-breath variability and dynamics that are nonlinear, complex, sensitive to initial conditions, unpredictable in the long-term, and chaotic. Hypercapnia, as produced by the inhalation of a CO(2)-enriched gas mixture, stimulates ventilation. Hypocapnia, as produced by mechanical hyperventilation, depresses ventilation in animals and in humans during sleep, but it does not induce apnea in awake humans. This emphasizes the suprapontine influences on ventilatory control. How cortical and subcortical commands interfere thus depend on the prevailing CO(2) levels. However, CO(2) also influences the variability and complexity of ventilation. This study was designed to describe how this occurs and to test the hypothesis that CO(2) chemoreceptors are important determinants of ventilatory dynamics. Spontaneous ventilatory flow was recorded in eight healthy subjects. Breath-by-breath variability was studied through the coefficient of variation of several ventilatory variables. Chaos was assessed with the noise titration method (noise limit) and characterized with numerical indexes [largest Lyapunov exponent (LLE), sensitivity to initial conditions; Kolmogorov-Sinai entropy (KSE), unpredictability; and correlation dimension (CD), irregularity]. In all subjects, under all conditions, a positive noise limit confirmed chaos. Hypercapnia reduced breathing variability, increased LLE (P = 0.0338 vs. normocapnia; P = 0.0018 vs. hypocapnia), increased KSE, and slightly reduced CD. Hypocapnia increased variability, decreased LLE and KSE, and reduced CD. These results suggest that chemoreceptors exert a strong influence on ventilatory variability and complexity. However, complexity persists in the quasi-absence of automatic drive. Ventilatory variability and complexity could be determined by the interaction between the respiratory central pattern generator and suprapontine structures. PMID:17218438

  14. SU-E-J-261: Statistical Analysis and Chaotic Dynamics of Respiratory Signal of Patients in BodyFix

    SciTech Connect

    Michalski, D; Huq, M; Bednarz, G; Lalonde, R; Yang, Y; Heron, D

    2014-06-01

    Purpose: To quantify respiratory signal of patients in BodyFix undergoing 4DCT scan with and without immobilization cover. Methods: 20 pairs of respiratory tracks recorded with RPM system during 4DCT scan were analyzed. Descriptive statistic was applied to selected parameters of exhale-inhale decomposition. Standardized signals were used with the delay method to build orbits in embedded space. Nonlinear behavior was tested with surrogate data. Sample entropy SE, Lempel-Ziv complexity LZC and the largest Lyapunov exponents LLE were compared. Results: Statistical tests show difference between scans for inspiration time and its variability, which is bigger for scans without cover. The same is for variability of the end of exhalation and inhalation. Other parameters fail to show the difference. For both scans respiratory signals show determinism and nonlinear stationarity. Statistical test on surrogate data reveals their nonlinearity. LLEs show signals chaotic nature and its correlation with breathing period and its embedding delay time. SE, LZC and LLE measure respiratory signal complexity. Nonlinear characteristics do not differ between scans. Conclusion: Contrary to expectation cover applied to patients in BodyFix appears to have limited effect on signal parameters. Analysis based on trajectories of delay vectors shows respiratory system nonlinear character and its sensitive dependence on initial conditions. Reproducibility of respiratory signal can be evaluated with measures of signal complexity and its predictability window. Longer respiratory period is conducive for signal reproducibility as shown by these gauges. Statistical independence of the exhale and inhale times is also supported by the magnitude of LLE. The nonlinear parameters seem more appropriate to gauge respiratory signal complexity since its deterministic chaotic nature. It contrasts with measures based on harmonic analysis that are blind for nonlinear features. Dynamics of breathing, so crucial for

  15. Experimental basis for laser-plasma interactions in ignition hohlraums at the National Ignition Facility

    SciTech Connect

    Froula, D H; Divol, L; London, R A; Berger, R L; Doeppner, T; Meezan, N B; Ralph, J; Ross, J S; Suter, L J; Glenzer, S H

    2009-11-12

    A series of laser plasma interaction experiments at OMEGA (LLE, Rochester) using gas-filled hohlraums shed light on the behavior of stimulated Raman scattering and stimulated Brillouin scattering at various plasma conditions encountered in indirect drive ignition designs. We present detailed experimental results that quantify the density, temperature, and intensity thresholds for both of these instabilities. In addition to controlling plasma parameters, the National Ignition Campaign relies on optical beam smoothing techniques to mitigate backscatter. We show that polarization smoothing is effective at controlling backscatter. These results provide an experimental basis for forthcoming experiments on National Ignition Facility.

  16. Risk assessment of mortality for all-cause, ischemic heart disease, cardiopulmonary disease, and lung cancer due to the operation of the world's largest coal-fired power plant

    NASA Astrophysics Data System (ADS)

    Kuo, Pei-Hsuan; Tsuang, Ben-Jei; Chen, Chien-Jen; Hu, Suh-Woan; Chiang, Chun-Ju; Tsai, Jeng-Lin; Tang, Mei-Ling; Chen, Guan-Jie; Ku, Kai-Chen

    2014-10-01

    Based on recent understanding of PM2.5 health-related problems from fossil-fueled power plants emission inventories collected in Taiwan, we have determined the loss of life expectancy (LLE) and the lifetime (75-year) risks for PM2.5 health-related mortalities as attributed to the operation of the world's largest coal-fired power plant; the Taichung Power Plant (TCP), with an installed nominal electrical capacity of 5780 MW in 2013. Five plausible scenarios (combinations of emission controls, fuel switch, and relocation) and two risk factors were considered. It is estimated that the lifetime (75-y) risk for all-cause mortality was 0.3%-0.6% for males and 0.2%-0.4% for females, and LLE at 84 days in 1997 for the 23 million residents of Taiwan. The risk has been reduced to one-fourth at 0.05%-0.10% for males and 0.03%-0.06% for females, and LLE at 15 days in 2007, which was mainly attributed to the installation of desulfurization and de-NOx equipment. Moreover, additional improvements can be expected if we can relocate the power plant to a downwind site on Taiwan, and convert the fuel source from coal to natural gas. The risk can be significantly reduced further to one-fiftieth at 0.001%-0.002% for males and 0.001% for females, and LLE at 0.3 days. Nonetheless, it is still an order higher than the commonly accepted elevated-cancer risk at 0.0001% (10-6), indicating that the PM2.5 health-related risk for operating such a world-class power plant is not negligible. In addition, this study finds that a better-chosen site (involving moving the plant to the leeward side of Taiwan) can reduce the risk significantly as opposed to solely transitioning the fuel source to natural gas. Note that the fuel cost of using natural gas (0.11 USD/kWh in 2013) in Taiwan is about twice the price of using coal fuel (0.05 USD/kWh in 2013).

  17. Synthesis and optimization of N-heterocyclic pyridinones as catechol-O-methyltransferase (COMT) inhibitors.

    PubMed

    Zhao, Zhijian; Harrison, Scott T; Schubert, Jeffrey W; Sanders, John M; Polsky-Fisher, Stacey; Zhang, Nanyan Rena; McLoughlin, Debra; Gibson, Christopher R; Robinson, Ronald G; Sachs, Nancy A; Kandebo, Monika; Yao, Lihang; Smith, Sean M; Hutson, Pete H; Wolkenberg, Scott E; Barrow, James C

    2016-06-15

    A series of N-heterocyclic pyridinone catechol-O-methyltransferase (COMT) inhibitors were synthesized. Physicochemical properties, including ligand lipophilic efficiency (LLE) and clogP, were used to guide compound design and attempt to improve inhibitor pharmacokinetics. Incorporation of heterocyclic central rings provided improvements in physicochemical parameters but did not significantly reduce in vitro or in vivo clearance. Nevertheless, compound 11 was identified as a potent inhibitor with sufficient in vivo exposure to significantly affect the dopamine metabolites homovanillic acid (HVA) and dihydroxyphenylacetic acid (DOPAC), and indicate central COMT inhibition. PMID:27133481

  18. Electric Fields Associated with Spherically Converging Shocks in Directly-Driven OMEGA Implosions

    NASA Astrophysics Data System (ADS)

    Li, C. K.; Zylstra, A.; Rosenberg, M. J.; Rinderknecht, H. G.; Frenje, J. A.; Seguin, F. H.; Petrasso, R. D.; Hu, S. X.; Betti, R.; Sangster, T. C.; Amendt, P. A.; Bellei, C.; Wilks, S. C.; Hoffman, N. M.; Nikroo, A.

    2014-10-01

    Time-gated, proton radiography provides direct measurements of radial electric fields and their temporal evolution in directly-driven capsule implosions. The experimental data indicate that such fields are associated with a spherically converging shock inside an imploding capsule. The implosions are simulated with the 2D hydrodynamic code DRACO. Several related mechanisms for generating such fields are discussed. The measurements provide physical insight into the structure, strength and dynamics of spherically converging shocks and have important implications in ICF implosion physics. This work was supported in part by the U.S. DOE, NLUF, LLNL and LLE.

  19. The risk equivalent of an exposure to-, versus a dose of radiation

    SciTech Connect

    Bond, V.P.

    1986-01-01

    The long-term potential carcinogenic effects of low-level exposure (LLE) are addressed. The principal point discussed is linear, no-threshold dose-response curve. That the linear no-threshold, or proportional relationship is widely used is seen in the way in which the values for cancer risk coefficients are expressed - in terms of new cases, per million persons exposed, per year, per unit exposure or dose. This implies that the underlying relationship is proportional, i.e., ''linear, without threshold''. 12 refs., 9 figs., 1 tab.

  20. Scientific Report (2002-2004)

    SciTech Connect

    Bedros Afeyan

    2004-05-11

    OAK-B135 An overview of our work as well as two recent publications are contained in this scientific report. The work reported here revolves around the discovery of new coherent nonlinear kinetic waves in laser produced plasmas, we call KEEN waves (kinetic, electrostatic electron nonlinear waves), and optical mixing experiments on the Imega laser system at LLE with blue-green light for the exploration of ways to suppress parametric instabilities in long scale length, long pulsewidth laser-plasmas such as those which will be found on NIF or LMJ.

  1. Non-rigid registration of medical images based on ordinal feature and manifold learning

    NASA Astrophysics Data System (ADS)

    Li, Qi; Liu, Jin; Zang, Bo

    2015-12-01

    With the rapid development of medical imaging technology, medical image research and application has become a research hotspot. This paper offers a solution to non-rigid registration of medical images based on ordinal feature (OF) and manifold learning. The structural features of medical images are extracted by combining ordinal features with local linear embedding (LLE) to improve the precision and speed of the registration algorithm. A physical model based on manifold learning and optimization search is constructed according to the complicated characteristics of non-rigid registration. The experimental results demonstrate the robustness and applicability of the proposed registration scheme.

  2. Broad spectrum drug screening using electron-ionization gas chromatography-mass spectrometry (EI-GCMS).

    PubMed

    Stone, Judy

    2010-01-01

    A liquid-liquid extraction (LLE) of drugs and internal standard (promazine) is performed by mixing urine at basic pH with 1-chlorobutane. There are no hydrolysis or derivatization steps. After centrifugation the organic (upper) layer is transferred to another tube and evaporated. The dried extract is reconstituted with ethyl acetate and 1 microL is injected onto the GCMS. Drugs are volatilized in the GC inlet and separated on a capillary column. In the EI source drugs become positively charged and fragment. Mass analysis of ionized fragments occurs with a single quadrupole. The resulting full scan mass spectra are automatically searched against three libraries. PMID:20077071

  3. Improvement of extraction capability of magnetic molecularly imprinted polymer beads in aqueous media via dual-phase solvent system.

    PubMed

    Hu, Yuling; Liu, Ruijin; Zhang, Yi; Li, Gongke

    2009-08-15

    In this study, a novel and simple dual-phase solvent system for the improvement of extraction capability of magnetic molecularly imprinted polymer (MIP) beads in aqueous sample was proposed. The method integrated MIP extraction and micro-liquid-liquid extraction (micro-LLE) into only one step. A magnetic MIP beads using atrazine as template was synthesized, and was applied to aqueous media by adding micro-volume of n-hexane to form a co-extraction system. The magnetic MIP beads preferred to suspend in the organic phase, which shielded them from the disturbance of water molecule. The target analytes in the water sample was extracted into the organic phase by micro-LLE and then further bound to the solid-phase of magnetic MIP beads. The beads specificity was significantly improved with the imprinting efficiency of template increasing from 0.5 to 4.4, as compared with that in pure aqueous media. The extraction capacity, equilibration process and cross-selectivity of the MIP dual-phase solvent extraction system were investigated. The proposed method coupled with high-performance liquid chromatography was applied to the analysis of atrazine, simazine, propazine, simetryn, prometryne, ametryn and terbutryn in complicated sample such as tomato, strawberry juice and milk. The method is selective, sensitive and low organic solvent-consuming, and has potential to broaden the range of MIP application in biological and environmental sample. PMID:19576415

  4. Determination of Rare Earth Elements in Hypersaline Solutions Using Low-Volume, Liquid-Liquid Extraction.

    PubMed

    Noack, Clinton W; Dzombak, David A; Karamalidis, Athanasios K

    2015-08-18

    Complex, hypersaline brines-including those coproduced with oil and gas, rejected from desalination technologies, or used as working fluids for geothermal electricity generation-could contain critical materials such as the rare earth elements (REE) in valuable concentrations. Accurate quantitation of these analytes in complex, aqueous matrices is necessary for evaluation and implementation of systems aimed at recovering those critical materials. However, most analytical methods for measuring trace metals have not been validated for highly saline and/or chemically complex brines. Here we modified and optimized previously published liquid-liquid extraction (LLE) techniques using bis(2-ethylhexyl) phosphate as the extractant in a heptane diluent, and studied its efficacy for REE recovery as a function of three primary variables: background salinity (as NaCl), concentration of a competing species (here Fe), and concentration of dissolved organic carbon (DOC). Results showed that the modified LLE was robust to a range of salinity, Fe, and DOC concentrations studied as well as constant, elevated Ba concentrations. With proper characterization of the natural samples of interest, this method could be deployed for accurate analysis of REE in small volumes of hyper-saline and chemically complex brines. PMID:25920439

  5. Detecting a wide range of environmental contaminants in human blood samples--combining QuEChERS with LC-MS and GC-MS methods.

    PubMed

    Plassmann, Merle M; Schmidt, Magdalena; Brack, Werner; Krauss, Martin

    2015-09-01

    Exposure to environmental pollution and consumer products may result in an uptake of chemicals into human tissues. Several studies have reported the presence of diverse environmental contaminants in human blood samples. However, previously developed multi-target methods for the analysis of human blood include a fairly limited amount of compounds stemming from one or two related compound groups. Thus, the sample preparation method QuEChERS (quick easy cheap effective rugged and safe) was tested for the extraction of 64 analytes covering a broad compound domain followed by detection using liquid and gas chromatography coupled to mass spectrometry (LC- and GC-MS). Forty-seven analytes showed absolute recoveries above 70% in the first QuEChERS step, being a simple liquid-liquid extraction (LLE) using acetonitrile and salt. The second QuEChERS step, being a dispersive solid phase extraction, did not result in an overall improvement of recoveries or removal of background signals. Using solely the LLE step, eight analytes could subsequently be detected in human blood samples from the German Environmental Specimen Bank. Using a LC-multiple reaction monitoring (MRM) method with a triple quadrupole instrument, better recoveries were achieved than with an older LC-high-resolution (HR) MS full scan orbitrap instrument, which required a higher concentration factor of the extracts. However, the application of HRMS full scan methods could be used for the detection of additional compounds retrospectively. PMID:26206704

  6. Optimisation of olive oil phenol extraction conditions using a high-power probe ultrasonication.

    PubMed

    Jerman Klen, T; Mozetič Vodopivec, B

    2012-10-15

    A new method of ultrasound probe assisted liquid-liquid extraction (US-LLE) combined with a freeze-based fat precipitation clean-up and HPLC-DAD-FLD-MS detection is described for extra virgin olive oil (EVOO) phenol analysis. Three extraction variables (solvent type; 100%, 80%, 50% methanol, sonication time; 5, 10, 20 min, extraction steps; 1-5) and two clean-up methods (n-hexane washing vs. low temperature fat precipitation) were studied and optimised with aim to maximise extracts' phenol recoveries. A three-step extraction of 10 min with pure methanol (5 mL) resulted in the highest phenol content of freeze-based defatted extracts (667 μg GAE g(-1)) from 10 g of EVOO, providing much higher efficiency (up to 68%) and repeatability (up to 51%) vs. its non-sonicated counterpart (LLE-agitation) and n-hexane washing. In addition, the overall method provided high linearity (r(2)≥0.97), precision (RSD: 0.4-9.3%) and sensitivity with LODs/LOQs ranging from 0.03 to 0.16 μg g(-1) and 0.10-0.51 μg g(-1) of EVOO, respectively. PMID:23442714

  7. β-lactam antibiotics residues analysis in bovine milk by LC-ESI-MS/MS: a simple and fast liquid-liquid extraction method.

    PubMed

    Jank, L; Hoff, R B; Tarouco, P C; Barreto, F; Pizzolato, T M

    2012-01-01

    This study presents the development and validation of a simple method for the detection and quantification of six β-lactam antibiotics residues (ceftiofur, penicillin G, penicillin V, oxacillin, cloxacillin and dicloxacillin) in bovine milk using a fast liquid-liquid extraction (LLE) for sample preparation, followed by liquid chromatography-electrospray-tandem mass spectrometry (LC-MS/MS). LLE consisted of the addition of acetonitrile to the sample, followed by addition of sodium chloride, centrifugation and direct injection of an aliquot into the LC-MS/MS system. Separation was performed in a C(18) column, using acetonitrile and water, both with 0.1% of formic acid, as mobile phase. Method validation was performed according to the criteria of Commission Decision 2002/657/EC. Limits of detection ranged from 0.4 (penicillin G and penicillin V) to 10.0 ng ml(-1) (ceftiofur), and linearity was achieved. The decision limit (CCα), detection capability (CCβ), accuracy, inter- and intra-day repeatability of the method are reported. PMID:21988179

  8. Mid-Holocene paleoceanographic conditions in the Limfjord region from gastropod (Littorina littorea) oxygen and carbon isotopes

    NASA Astrophysics Data System (ADS)

    Burman, J.; Schmitz, B.

    2003-04-01

    Stable oxygen and carbon isotope intrashell transects of common intertidal gastropods Littorina littorea have been used to reconstruct environmental conditions in the Limfjord region during the mid-Holocene (late Atlantic time). The subfossil specimens studied are from the excavated Stone Age Kitchenmidden in Ertebølle, northern Denmark, dated between 5970±95 to 5070±90 B.P. In addition recent specimens were studied from different coastal localities within the Limfjord, along a salinity gradient from the west to east. These modern shells were used as control samples, in order to construct an oceanographic model for the Limfjord, in which the seasonal isotopic range from the Littorina subfossils could be interpreted. The coastal marine climate in the Ertebølle region during the mid-Holocene indicates summer-SST close to 22^oC and 4-5 ppm reduced salinity compared to fully marine conditions. The mid-Holocene central Limfjord can be described as a coastal area, which experienced similar salinity conditions (c. 30.5 PSU) that prevail in the western part (Odden area) today. In terms of summer-SST as compared with a 10-year average (1989-1998) for the Limfjord region, temperatures were 2-3^oC above recent climatic settings. These results point towards a mid-Holocene Limfjord in contact with the North Sea/Skagerrak with possibly more pronounced water exchange with the North Sea than today.

  9. Searching for R-parity violation at run-II of the tevatron.

    SciTech Connect

    Allanach, B.; Banerjee, S.; Berger, E. L.; Chertok, M.; Diaz, M. A.; Dreiner, H.; Eboli, O. J. P.; Harris, B. W.; Hewett, J.; Magro, M. B.; Mondal, N. K.; Narasimham, V. S.; Navarro, L.; Parua, N.; Porod, W.; Restrepo, D. A.; Richardson, P.; Rizzo, T.; Seymour, M. H.; Sullivan, Z.; Valle, J. W. F.; de Campos, F.

    1999-06-22

    The authors present an outlook for possible discovery of supersymmetry with broken R-parity at Run II of the Tevatron. They first present a review of the literature and an update of the experimental bounds. In turn they then discuss the following processes: (1) resonant slepton production followed by R{sub P} decay, (a) via LQD{sup c} and (b) via LLE{sup c}; (2) how to distinguish resonant slepton production from Z{prime} or W{prime} production; (3) resonant slepton production followed by the decay to neutralino LSP, which decays via LQD{sup c}; (4) resonant stop production followed by the decay to a chargino, which cascades to the neutralino LSP; (5) gluino pair production followed by the cascade decay to charm squarks which decay directly via L{sub 1}Q{sub 2}D{sub 1}{sup c}; (6) squark pair production followed by the cascade decay to the neutralino LSP which decays via L{sub 1}Q{sub 2}D{sub 1}{sup c}; (7) MSSM pair production followed by the cascade decay to the LSP which decays (a) via LLE{sup c}, (b) via LQD{sup c}, and (c) via U{sup c}D{sup c}D{sup c}, respectively; and (8) top quark and top squark decays in spontaneous R{sub P}.

  10. An enzyme-linked immunosorbent assay for detecting 3-phenoxybenzoic acid in plasma and its application in farmers and consumers

    PubMed Central

    Thiphom, Sarunya; Prapamontol, Tippawan; Chantara, Somporn; Mangklabruks, Ampica; Suphavilai, Chaisuree; Ahn, Ki Chang; Gee, Shirley J.; Hammock, Bruce D.

    2013-01-01

    The aim of this study was to identify a plasma biomarker of exposure to pyrethroid insecticides. A major metabolite, 3-phenoxybenzoic acid (3-PBA), can be detected in urine but urinary 3-PBA cannot be used to assess the active dose. The 3-PBA-adduct represents a much more persistent class of biomarkers than metabolites excreted into urine, having half lives up to several weeks or months. We developed an enzyme-linked immunosorbent assay (ELISA) for total 3-PBA including adduct formed after alkaline hydrolysis, liquid-liquid extraction (LLE) and solid phase extraction (SPE) of the sample. The developed ELISA had an IC50 value of 26.7 ng/mL. The intra- and inter-assay coefficients of variation (%CV) were lower than 5% and were within the optimum condition variance (OCV) range. The LLE cleanup technique satisfactorily eliminated the matrix effect from plasma samples before SPE and ELISA analysis yielding good recoveries (85.9–99.4%) with a limit of quantitation (LOQ, 5 ng/mL) that was 30- to 47-fold more sensitive than previous studies. Moreover, the developed method could separate more than 80% of 3-PBA from adduct form. The method was successfully applied to the detection of the target in real samples obtained from consumers (n=50) and farmers (n=50). To our knowledge, this is the first ELISA method for detecting 3-PBA in human plasma and applied to a field study. PMID:23667388

  11. The multiple-pulse driver line on the OMEGA laser

    NASA Astrophysics Data System (ADS)

    Kosc, T. Z.; Kelly, J. H.; Hill, E. M.; Dorrer, C.; Waxer, L. J.; Donaldson, W. R.

    2015-02-01

    The multiple-pulse driver line (MPD) provides on-shot co-propagation of two separate pulse shapes in all 60 OMEGA beams at the Laboratory for Laser Energetics (LLE). The two co-propagating pulse shapes would typically be (1) a series of 100-ps "picket" pulses followed by (2) a longer square or shaped "drive" pulse. Smoothing by spectral dispersion (SSD), which increases the laser bandwidth, can be applied to either one of the two pulse shapes. Therefore, MPD allows for dynamic bandwidth reduction, where the bandwidth is applied only to the picket portion of a pulse shape. Since the use of SSD decreases the efficiency of frequency conversion from the IR to the UV, dynamic bandwidth reduction provides an increase in the drive-pulse energy. The design of the MPD required careful consideration of beam combination as well as the minimum pulse separation for two pulses generated by two separate sources. A new combined-pulse-shape diagnostic needed to be designed and installed after the last grating used for SSD. This new driver-line flexibility is built into the OMEGA front end as one component of the initiative to mitigate cross-beam energy transfer on target and to demonstrate hydro-equivalent ignition on the OMEGA laser at LLE.

  12. Effects of inspiratory loading on the chaotic dynamics of ventilatory flow in humans.

    PubMed

    Samara, Ziyad; Raux, Mathieu; Fiamma, Marie-Noëlle; Gharbi, Alexandre; Gottfried, Stewart B; Poon, Chi-Sang; Similowski, Thomas; Straus, Christian

    2009-01-01

    Human ventilation at rest exhibits complexity and chaos. The aim of this study was to determine whether suprapontine interferences with the automatic breathing control could contribute to ventilatory chaos. We conducted a post hoc analysis of a previous study performed in awake volunteers exhibiting cortical pre-motor potentials during inspiratory loading. In eight subjects, flow was recorded at rest, while breathing against inspiratory threshold loads (median 21.5 cm H(2)O) and resistive loads (50 cm H(2)Ol(-1)s(-1)) loads, and while inhaling 7% CO(2)-93% O(2). Chaos was identified through noise titration (noise limit, NL) and the sensitivity to initial conditions was assessed through the largest Lyapunov exponent (LLE). Breath-by-breath variability was evaluated using the coefficient of variation of several ventilatory variables. Chaos was consistently present in ventilatory flow recordings, but mechanical loading did not alter NL, LLE, or variability. In contrast, CO(2) altered chaos and reduced variability. In conclusion, inspiratory loading - and any resultant respiratory-related cortical activity - were not associated with changes in ventilatory chaos in this study, arguing against suprapontine contributions to ventilatory complexity. PMID:19013545

  13. Acoustic emission-based condition monitoring methods: Review and application for low speed slew bearing

    NASA Astrophysics Data System (ADS)

    Caesarendra, Wahyu; Kosasih, Buyung; Tieu, Anh Kiet; Zhu, Hongtao; Moodie, Craig A. S.; Zhu, Qiang

    2016-05-01

    This paper presents an acoustic emission-based method for the condition monitoring of low speed reversible slew bearings. Several acoustic emission (AE) hit parameters as the monitoring parameters for the detection of impending failure of slew bearings are reviewed first. The review focuses on: (1) the application of AE in typical rolling element bearings running at different speed classifications, i.e. high speed (>600 rpm), low speed (10-600 rpm) and very low speed (<10 rpm); (2) the commonly used AE hit parameters in rolling element bearings and (3) AE signal processing, feature extraction and pattern recognition methods. In the experiment, impending failure of the slew bearing was detected by the AE hit parameters after the new bearing had run continuously for approximately 15 months. The slew bearing was then dismantled and the evidence of the early defect was analysed. Based on the result, we propose a feature extraction method of the AE waveform signal using the largest Lyapunov exponent (LLE) algorithm and demonstrate that the LLE feature can detect the sign of failure earlier than the AE hit parameters with improved prediction of the progressive trend of the defect.

  14. The Dortmund Data Bank: A computerized system for retrieval, correlation, and prediction of thermodynamic properties of mixtures

    SciTech Connect

    Onken, U.; Rarey-Nies, J.; Gmehling, J. )

    1989-05-01

    The Dortmund Data Bank (DDB) was started in 1973 with the intention to employ the vast store of vapor-liquid equilibrium (VLE) data from the literature for the development of models for the prediction of VLE. From the beginning, the structure of the DDB has been organized in such a way that it was possible to take advantage of the full potential of electronic computers. With the experience gained in fitting and processing VLE data, the authors extended the DDB system to other types of mixture properties, i.e., liquid-liquid equilibria (LLE), gas solubilities (GLE), activity coefficients at infinite dilution ({gamma}{sup {infinity}}), heats of mixing h{sup E}, and excess heat capacities. Besides the files for mixture properties, the DDB contains pure-component data and program packages for various applications. New experimental data are checked for consistency before they are stored. For data retrieval user-specified search masks can be used. The data files are available via an online data service and through the Dechema Chemistry Data Series. For the purpose of data correlation and model testing, parameter fitting is performed with an optimization routine (Nelder-Mead). In the past years the DDB system has been successfully employed for the development of prediction methods for VLE, LLE, GLE, {gamma}{sup {infinity}}, and h{sup E} (UNIFAC, mod. UNIFAC, etc.).

  15. Development and comparison of two dispersive liquid-liquid microextraction techniques coupled to high performance liquid chromatography for the rapid analysis of bisphenol A in edible oils.

    PubMed

    Liu, Shuhui; Xie, Qilong; Chen, Jie; Sun, Janzhi; He, Hui; Zhang, Xiaoke

    2013-06-21

    In this study, two novel sample extraction methods for the analysis of bisphenol A (BPA) in edible oils were developed by using liquid-liquid extraction followed by a dispersive liquid-liquid microextraction (LLE-DLLME) and reversed-phase dispersive liquid-liquid microextraction (RP-DLLME). RP-DLLME showed a superior characteristic over LLE-DLLME and other previously reported procedures because of its easy operation, short extraction time, high sensitivity, low organic solvent consumption and waste generation. The optimized extraction conditions of RP-DLLME for 1.0 g of edible oil diluted in 4 mL of n-hexane were: extractant, 100 μL 0.2 M sodium hydroxide solution (80% methanol, v/v); extraction time, 1 min; centrifugation, 3 min. The determination of BPA was carried out by high performance liquid chromatography coupled with a DAD detector. The method offered excellent linearity over a range of 0.010-0.5 μg g(-1) with a correlation coefficient of r>0.997. Intra-day and inter-day repeatability values expressed as relative standard deviation were 1.9% and 5.9%, respectively. The quantitation limit and detection limit were 6.3 and 2.5 ng g(-1). The target analyte was detected in 5 out of 16 edible oil samples. The recovery rates in real samples ranged from 89.5 to 99.7%. PMID:23683892

  16. [A Standing Balance Evaluation Method Based on Largest Lyapunov Exponent].

    PubMed

    Liu, Kun; Wang, Hongrui; Xiao, Jinzhuang; Zhao, Qing

    2015-12-01

    In order to evaluate the ability of human standing balance scientifically, we in this study proposed a new evaluation method based on the chaos nonlinear analysis theory. In this method, a sinusoidal acceleration stimulus in forward/backward direction was forced under the subjects' feet, which was supplied by a motion platform. In addition, three acceleration sensors, which were fixed to the shoulder, hip and knee of each subject, were applied to capture the balance adjustment dynamic data. Through reconstructing the system phase space, we calculated the largest Lyapunov exponent (LLE) of the dynamic data of subjects' different segments, then used the sum of the squares of the difference between each LLE (SSDLLE) as the balance capabilities evaluation index. Finally, 20 subjects' indexes were calculated, and compared with evaluation results of existing methods. The results showed that the SSDLLE were more in line with the subjects' performance during the experiment, and it could measure the body's balance ability to some extent. Moreover, the results also illustrated that balance level was determined by the coordinate ability of various joints, and there might be more balance control strategy in the process of maintaining balance. PMID:27079089

  17. OMEGA: A NEW COLD X-RAY SIMULATION FACILITY FOR THE EVALUATION OF OPTICAL COATINGS

    SciTech Connect

    Fisher, J H; Newlander, C D; Fournier, K B; Beutler, D E; Coverdale, C A; May, M J; Tobin, M; Davis, J F; Shiekh, D

    2007-04-27

    We report on recent progress for the development of a new cold X-ray optical test capability using the Omega Facility located at the Laboratory for Laser Energetics (LLE) at the University of Rochester. These tests were done on the 30 kJ OMEGA laser at the Laboratory for Laser Energetics (LLE) at the University of Rochester, Rochester, NY. We conducted a six-shot series called OMEGA II on 14 July 2006 in one eight-hour day (supported by the Defense Threat Reduction Agency). The initial testing was performed using simple protected gold optical coatings on fused silica substrates. PUFFTFT analyses were completed and the specimen's thermal lateral stress and transverse stress conditions were calculated and interpreted. No major anomalies were detected. Comparison of the pre- and posttest reflective measurements coupled with the TFCALC analyses proved invaluable in guiding the analyses and interpreting the observed damage. The Omega facility is a high quality facility for performing evaluation of optical coatings and coupons and provides experience for the development of future National Ignition Facility (NIF) testing.

  18. Time Evolution and Asymmetries of OMEGA Direct-Drive D^3He Capsule Implosions Inferred from 3.0- and 14.7-MeV Protons and 3.6-MeV Alphas

    NASA Astrophysics Data System (ADS)

    Seguin, F. H.; Petrasso, R. D.; Frenje, J. A.; Li, C. K.; Rygg, J. R.; Stoeckl, C.; Radha, P. B.; Delettrez, J. A.; Glebov, V. N.; Meyerhofer, D. D.; Sangster, T. C.; Soures, J. M.

    2002-11-01

    Fusion of D and ^3He in direct-drive, spherical-capsule implosions results in the copious production of several charged fusion products that lose energy as they pass out through the hot fuel plasma and the cool (<=1 keV) shell plasma. Energy losses reflect the areal density (ρ L) of the plasma transited at the instant of burn. In experiments on OMEGA, up to 11 spectrometers were used to simultaneously measure spectra of D^3He protons from different directions for information about the symmetry and time evolution of ρL. There are often significant differences in the individual spectra from one implosion, both in mean energy loss and in maximum energy loss, which largely reflect nonuniformities in the shell. D^3He protons are also produced at first shock coalescence when the capsule is far less compressed, and they escape with energy losses indicating lower areal densities at that time. We examine whether asymmetries are detectable at first shock coalesence, and whether they are then amplified by bang time. This work was supported in part by the U.S. DOE Office of Inertial Confinement Fusion (Grant number DE-FG03-99DP00300 and Cooperative Agreement number DE-FC03-92SF19460), LLE (subcontract P0410025G), LLNL (subcontract B313975). (Petrasso: Visiting Senior Scientist at LLE.)

  19. Evaluation of Limb Load Asymmetry Using Two New Mathematical Models

    PubMed Central

    Kumar, Senthil NS; Omar, Baharudin; Joseph, Leonard H.; Htwe, Ohnmar; Jagannathan, K.; Hamdan, Nor M Y; Rajalakshmi, D.

    2015-01-01

    Quantitative measurement of limb loading is important in orthopedic and neurological rehabilitation. In current practice, mathematical models such as Symmetry index (SI), Symmetry ratio (SR), and Symmetry angle (SA) are used to quantify limb loading asymmetry. Literatures have identified certain limitations with the above mathematical models. Hence this study presents two new mathematical models Modified symmetry index (MSI) and Limb loading error (LLE) that would address these limitations. Furthermore, the current mathematical models were compared against the new model with the goal of achieving a better model. This study uses hypothetical data to simulate an algorithmic preliminary computational measure to perform with all numerical possibilities of even and uneven limb loading that can occur in human legs. Descriptive statistics are used to interpret the limb loading patterns: symmetry, asymmetry and maximum asymmetry. The five mathematical models were similar in analyzing symmetry between limbs. However, for asymmetry and maximum asymmetry data, the SA and SR values do not give any meaningful interpretation, and SI gives an inflated value. The MSI and LLE are direct, easy to interpret and identify the loading patterns with the side of asymmetry. The new models are notable as they quantify the amount and side of asymmetry under different loading patterns. PMID:25716372

  20. Method development aspects for the quantitation of pharmaceutical compounds in human plasma with a matrix-assisted laser desorption/ionization source in the multiple reaction monitoring mode.

    PubMed

    Kovarik, Peter; Grivet, Chantal; Bourgogne, Emmanuel; Hopfgartner, Gérard

    2007-01-01

    The present work investigates various method development aspects for the quantitative analysis of pharmaceutical compounds in human plasma using matrix-assisted laser desorption/ionization and multiple reaction monitoring (MALDI-MRM). Talinolol was selected as a model analyte. Liquid-liquid extraction (LLE) and protein precipitation were evaluated regarding sensitivity and throughput for the MALDI-MRM technique and its applicability without and with chromatographic separation. Compared to classical electrospray liquid chromatography/mass spectrometry (LC/ESI-MS) method development, with MALDI-MRM the tuning of the analyte in single MS mode is more challenging due to interfering matrix background ions. An approach is proposed using background subtraction. With LLE and using a 200 microL human plasma aliquot acceptable precision and accuracy could be obtained in the range of 1 to 1000 ng/mL without any LC separation. Approximately 3 s were required for one analysis. A full calibration curve and its quality control samples (20 samples) can be analyzed within 1 min. Combining LC with the MALDI analysis allowed improving the linearity down to 50 pg/mL, while reducing the throughput potential only by two-fold. Matrix effects are still a significant issue with MALDI but can be monitored in a similar way to that used for LC/ESI-MS analysis. PMID:17295425

  1. Towards the determination of the equation of state of hydrogen and helium at extreme densities: Laser induced shocks on pre-compressed samples.

    NASA Astrophysics Data System (ADS)

    Loubeyre, Paul

    2005-03-01

    The determination of the equation of state of helium and hydrogen at very high density is an important problem at the frontier between condensed matter physics and plasma physics. It is also an important issue in planetary physics for understanding the formation of giant and extrasolar planets. However, the extreme densities relevant to most of the interior of Jupiter are unreachable by either static or single-shock compression techniques alone. Recently, a laser-driven shock-wave in a hydrogen sample, pre-compressed in a diamond anvil cell, has been demonstrated [1]. Consequently, the compression factors of the dynamic and static techniques can now be multiplied. We will present our current effort with the Omega laser at LLE to measure accurately the Hugoniot curves of hydrogen and helium pre-compressed up to 1.5 GPa. The metrology and error bars of the measurements will be discussed. The Hugoniot data points will be compared to published calculations, and an interesting difference in the insulator-metal transition of hydrogen and helium will be discussed. Co-authors are Stephanie Brygoo, CEA, France; Jon Eggert, Peter Celliers, Guilbert Collins, LLNL, Livermore CA 94551 USA; Ryan McWilliam, Raymond Jeanloz, University of California, CA 94720 USA; and Tom Boehly, LLE, New-York 14623 USA. [1] P. Loubeyre et al., High Pressure Research 24, 25- 31 (2004).

  2. Time-Resolved Tandem Faraday Cup for High Energy TNSA Particles

    NASA Astrophysics Data System (ADS)

    Padalino, Stephen; Simone, Angela; Turner, Ethan; Ginnane, Mary Kate; Dubois, Natalie; Sangster, Craig; Regan, Sean

    2014-10-01

    MTW and OMEGA EP Lasers at LLE utilize ultra-intense laser light to produce bursts of high-energy ions through Target Normal Sheath Acceleration (TNSA). A Time Resolved Tandem Faraday Cup (TFC) is being designed to collect and differentiate protons and alphas from heavy ions produced during TNSA. The TFC will be comprised of a replaceable thickness absorber capable of stopping a range of user-selectable heavy ions. Ions heavier than alphas emitted from the TNSA plasma will stop within the primary TFC, while less massive particles will continue through and deposit their remaining charge in the secondary TFC. The time-resolved beam current generated in each cup will be measured on a fast storage scope in multiple channels. Secondary electrons released from the impact of heavy ions with the cups will be suppressed by magnetic and electrostatic fields. A charge-exchange foil at the TFC entrance will modify the charge state distribution of the heavy ions produced by the plasma to a known distribution. Using the known distribution and the time of flight of the heavy ions, the total heavy ion current can be determined. Ultimately the TFC will be used to normalize a variety of nuclear physics cross sections and stopping power measurements. Funded in part by a LLE contract through the DOE.

  3. Recycling of indium from CIGS photovoltaic cells: potential of combining acid-resistant nanofiltration with liquid-liquid extraction.

    PubMed

    Zimmermann, Yannick-Serge; Niewersch, Claudia; Lenz, Markus; Kül, Zöhre Zohra; Corvini, Philippe F-X; Schäffer, Andreas; Wintgens, Thomas

    2014-11-18

    Electronic consumer products such as smartphones, TV, computers, light-emitting diodes, and photovoltaic cells crucially depend on metals and metalloids. So-called "urban mining" considers them as secondary resources since they may contain precious elements at concentrations many times higher than their primary ores. Indium is of foremost interest being widely used, expensive, scarce and prone to supply risk. This study first investigated the capability of different nanofiltration membranes of extracting indium from copper-indium-gallium- selenide photovoltaic cell (CIGS) leachates under low pH conditions and low transmembrane pressure differences (<3 bar). Retentates were then subjected to a further selective liquid-liquid extraction (LLE). Even at very acidic pH indium was retained to >98% by nanofiltration, separating it from parts of the Ag, Sb, Se, and Zn present. LLE using di-(2-ethylhexyl)phosphoric acid (D2EHPA) extracted 97% of the indium from the retentates, separating it from all other elements except for Mo, Al, and Sn. Overall, 95% (2.4 g m(-2) CIGS) of the indium could be extracted to the D2EHPA phase. Simultaneously, by nanofiltration the consumption of D2EHPA was reduced by >60% due to the metal concentration in the reduced retentate volume. These results show clearly the potential for efficient scarce metal recovery from secondary resources. Furthermore, since nanofiltration was applicable at very low pH (≥ 0.6), it may be applied in hydrometallurgy typically using acidic conditions. PMID:25310266

  4. Challenges Associated with Sample Preparation for the Analysis of PBDEs in Human Serum.

    PubMed

    Siddique, Shabana; Kosarac, Ivana; Kubwabo, Cariton; Harris, Shelley

    2016-01-01

    Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in many applications; however, certain PBDE congeners are persistent, bioaccumulative, and toxic to both humans and the environment. PBDEs have been found in human specimens, and a variety of analytical techniques have been used for their determination in biological matrixes. Nevertheless, obtaining a relatively clean analytical blank sample during PBDE analysis is a big challenge because of the ubiquitous nature of these compounds. Thus, the present study was conducted to compare the PBDE background levels associated with the three most commonly used extraction techniques: liquid-liquid extraction (LLE), SPE, and accelerated solvent extraction (ASE). Conventionally used blank matrixes (HPLC grade water, Milli-Q water, and air) were spiked with internal standards and extracted using LLE, SPE, or ASE. The extracts were analyzed by GC/electron ionization-tandem MS. The ASE method achieved the lowest background levels for nearly all the PBDE congeners analyzed, which may be attributed to the stainless steel and closed-vessel nature of the ASE cells. PMID:26823234

  5. Aspergillus nidulans catalase-peroxidase gene (cpeA) is transcriptionally induced during sexual development through the transcription factor StuA.

    PubMed

    Scherer, Mario; Wei, Huijun; Liese, Ralf; Fischer, Reinhard

    2002-10-01

    Catalases, peroxidases, and catalase-peroxidases are important enzymes to cope with reactive oxygen species in pro- and eukaryotic cells. In the filamentous fungus Aspergillus nidulans three monofunctional catalases have been described, and a fourth catalase activity was observed in native polyacrylamide gels. The latter activity is probably due to the bifunctional enzyme catalase-peroxidase, which we characterized here. The gene, named cpeA, encodes an 81-kDa polypeptide with a conserved motif for heme coordination. The enzyme comprises of two similar domains, suggesting gene duplication and fusion during evolution. The first 439 amino acids share 22% identical residues with the C terminus. Homologous proteins are found in several prokaryotes, such as Escherichia coli and Mycobacterium tuberculosis (both with 61% identity). In fungi the enzyme has been noted in Penicillium simplicissimum, Septoria tritici, and Neurospora crassa (69% identical amino acids) but is absent from Saccharomyces cerevisiae. Expression analysis in A. nidulans revealed that the gene is transcriptionally induced upon carbon starvation and during sexual development, but starvation is not sufficient to reach high levels of the transcript during development. Besides transcriptional activation, we present evidence for posttranscriptional regulation. A green fluorescent protein fusion protein localized to the cytoplasm of Hülle cells. The Hülle cell-specific expression was dependent on the developmental regulator StuA, suggesting an activating function of this helix-loop-helix transcription factor. PMID:12455692

  6. Performance Characterization of RaPToRS Systems

    NASA Astrophysics Data System (ADS)

    Shibata, K.; Krieger, M.; Fallica, J.; Henchen, R.; Pogozelski, E.; Padalino, S.; SUNY Geneseo Collaboration; LaboratoryLaser Energetics at University of Rochester Collaboration

    2011-10-01

    The Rapid Pneumatic Transport of Radioactive Samples (RaPToRS) system can quickly and efficiently move radioactive materials from their activation site to a counting station. Facilities such as the NIF and LLE are considering these systems while NRL is currently using one. The system is essentially a 10 cm diameter pneumatic tube with a cylindrical sample carrier. The performance of the system depends on many factors, including the mass of the carrier, length of the tube, angle and difference in height of the tube's endpoints, the carrier's physical design, and the number, type, and distribution of blowers attached to the tube. These factors have been systematically examined to develop the fastest and most reliable system. The most significant factors are the mass and the vertical travel of the carrier. When the carrier mass is low, moving air supports the carrier in the tube, resulting in low friction. The terminal velocity ranges from 13.5 to 2.5 m/s for masses varying from 1 kg to 3 kg. Using a single 1100 W blower, the initial force exerted on the carrier was 11.3 N. This work was supported in part by the US Department of Energy through the LLE.

  7. A simple and reliable liquid chromatography-tandem mass spectrometry method for the determination of aflatoxin M1 in milk.

    PubMed

    Biancardi, A; Piro, R; Dall'asta, C; Galaverna, G

    2013-01-01

    A new chromatographic method is proposed for the analysis of aflatoxin M(1) in milk. The method is based on liquid-liquid extraction followed by LC-MS/MS analysis. Liquid-liquid extraction (LLE) is performed on the defatted milk plus sodium chloride by using ethyl acetate as an extraction solvent. Accuracy and precision were evaluated at the LOQ (15 ng kg(-1)) spiked sample as well as with three other different naturally contaminated reference materials. The mean overall recovery (n = 24) was 95% with a confidence interval of 1.9% and a CV% of 4.5%. The performance of the proposed method was compared with that of the Official ISO Method based on the use of immunoaffinity chromatography columns (IAC): LLE protocol could be considered a valid alternative to the LC-IAC. In general it showed better accuracy with lower data dispersion. Moreover, the sample preparation is very simple and straightforward, potentially being applicable as a high-throughput method which, on account of its simplicity and low cost, may be applied to the analysis of a large number of samples in the occasion of outbreaks of large-scale contamination. PMID:23176386

  8. Micro-extraction techniques in analytical toxicology: short review.

    PubMed

    Flanagan, R J; Morgan, P E; Spencer, E P; Whelpton, R

    2006-01-01

    This paper discusses new developments in plasma micro-extraction techniques in the context of established micro-extraction and protein precipitation methodology. Simple liquid-liquid solvent extraction (LLE) of plasma with direct GC or HPLC analysis of the resulting extract has been used for many years. Butyl acetate and methyl t-butyl ether (MTBE) give efficient extraction of many drugs and metabolites from small volumes of plasma or whole blood at an appropriate pH, and form the upper layer, thus simplifying extract removal. Butyl acetate does not interfere with NPD, ECD or MS in GC, whilst MTBE has a relatively low UV cutoff (220 nm). Thus, HPLC eluents that use a high proportion of an organic component allow MTBE extracts to be analysed directly. 'Salting-out' and extractive derivatization using acetic anhydride or phenylboronic acid can be used with appropriate analytes. As regards protein precipitation, an important consideration is lowering the pH, although this is not feasible with acid-labile analytes. More recent developments include sold-phase micro-extraction (SPME) and liquid-phase micro-extraction (LPME). This latter technique especially may prove invaluable as analytes that cannot easily be extracted with LLE can be isolated simply at low cost with a minimum of apparatus. PMID:16779788

  9. Assessing the lipophilicity of fragments and early hits.

    PubMed

    Mortenson, Paul N; Murray, Christopher W

    2011-07-01

    A key challenge in many drug discovery programs is to accurately assess the potential value of screening hits. This is particularly true in fragment-based drug design (FBDD), where the hits often bind relatively weakly, but are correspondingly small. Ligand efficiency (LE) considers both the potency and the size of the molecule, and enables us to estimate whether or not an initial hit is likely to be optimisable to a potent, druglike lead. While size is a key property that needs to be controlled in a small molecule drug, there are a number of additional properties that should also be considered. Lipophilicity is amongst the most important of these additional properties, and here we present a new efficiency index (LLE(AT)) that combines lipophilicity, size and potency. The index is intuitively defined, and has been designed to have the same target value and dynamic range as LE, making it easily interpretable by medicinal chemists. Monitoring both LE and LLE(AT) should help both in the selection of more promising fragment hits, and controlling molecular weight and lipophilicity during optimisation. PMID:21614595

  10. Light lithophile elements in pyroxenes of Northwest Africa (NWA) 817 and other Martian meteorites: Implications for water in Martian magmas

    NASA Astrophysics Data System (ADS)

    Treiman, Allan H.; Musselwhite, Donald S.; Herd, Christopher D. K.; Shearer, Charles K.

    2006-06-01

    Zoning patterns of light lithophile elements (the LLE: Li, Be, and B) in pyroxenes of some Martian basaltic meteorites have been used to suggest that the parent basalts were saturated in water and exsolved an aqueous fluid phase. Here, we examine LLE zoning in the augites of a quickly cooled Martian basalt that was not water-saturated—the Northwest Africa (NWA) 817 nakhlite. Analyses for LLE were by secondary ion mass spectrometry (SIMS), supported by EMP analyses of major and minor elements. In NWA 817, zoning of Be and B is consistent with igneous fractionations while Li abundances are effectively constant across wide ranges in abundance of other incompatible elements (Be, B, Ti, and Fe*). The lack of strong zoning in Li can be ascribed to intracrystalline diffusion, despite the rapid cooling of NWA 817. Most other nakhlites, notably Nakhla and Lafayette, cooled more slowly than did NWA 817 [Treiman, A.H., 2005. The nakhlite Martian meteorites: augite-rich igneous rock from Mars. Chem. Erde65, 203-270]. In them Li abundances are constant across augite, as are abundances of other elements. In Nakhla pyroxenes, all the LLE have effectively constant abundances across significant ranges in Fe* and Ti abundance. Lafayette is more equilibrated still, and shows constant abundances of LLE and nearly constant Fe*. A pyroxene in the NWA480 shergottite has constant Li abundances, and was interpreted to represent mineral fractionation coupled with exsolution of aqueous fluid. A simple quantitative model of this process requires that the partitioning of Li between basalt and aqueous fluid, LiDaq/bas, be 15 times larger than its experimentally determined value. Thus, its seems unlikely that the Li zoning pattern in NWA480 augite represents exsolution of aqueous fluid. Late igneous or sub-solidus diffusion seems more likely as is suggested by Li isotopic studies [Beck, P., Chaussidon, M., Barrat, J.-A., Gillet, Ph., Bohn, M., 2005. An ion-microprobe study of lithium isotopes