Sample records for gain medium comprising

  1. Microwave gain medium with negative refractive index.

    PubMed

    Ye, Dexin; Chang, Kihun; Ran, Lixin; Xin, Hao

    2014-12-19

    Artificial effective media are attractive because of the fantastic applications they may enable, such as super lensing and electromagnetic invisibility. However, the inevitable loss due to their strongly dispersive nature is one of the fundamental challenges preventing such applications from becoming a reality. In this study, we demonstrate an effective gain medium based on negative resistance, to overcompensate the loss of a conventional passive metamaterial, meanwhile keeping its original negative-index property. Energy conservation-based theory, full-wave simulation and experimental measurement show that a fabricated sample consisting of conventional sub-wavelength building blocks with embedded microwave tunnel diodes exhibits a band-limited Lorentzian dispersion simultaneously with a negative refractive index and a net gain. Our work provides experimental evidence to the assertion that a stable net gain in negative-index gain medium is achievable, proposing a potential solution for the critical challenge current metamateiral technology faces in practical applications.

  2. Active medium gain study of electric-discharge oxygen-iodine laser

    NASA Astrophysics Data System (ADS)

    Kolobyanin, Yuriy; Adamenkov, Yuriy; Vyskubenko, Boris; Goryachev, Leonid; Ilyin, Sergey; Kalashnik, Anatoliy; Rakhimova, Tatiana; Rogozhnikov, Georgiy

    2007-05-01

    The paper reports on experimental studies of the active medium gain in supersonic electric-discharge oxygen-iodine laser (DOIL) based on traveling mw discharge. The measurements have included: absolute concentration, yield, and energy efficiency of production of SO in pure oxygen and oxygen-helium mixes at an oxygen partial pressure 3 to 15 Torr. For the gas flow to get rid of atomic oxygen, both heterogeneous mercury oxide coatings of the tube walls and homogeneous additives to the work mix, such as nitrogen oxide, have been used. The active medium of DOIL was formed using a nozzle array of the type of ejector sized as 10*50 mm2. The singlet oxygen-helium mix was supplied through three rows of sonic cylindrical nozzles, while the iodine-carrier gas mix - through two rows of supersonic conical nozzles with a half-opening angle of 10°(arc). The gas-phase iodine was produced in a quartz cell filled with iodine crystals. Room-temperature iodine vapors were picked up with a carrier gas (nitrogen or helium) and thus delivered into the nozzle array. The active medium was investigated by the high-resolution laser diode spectroscopy approach that used the laser type Vortex 6025 purchased from New Focus, Inc. The laser medium gain factor was determined by the intra-cavity approach having a sensitivity about 1*10 -6 cm -1. The static temperature of the medium was determined from the measurements of gain half-width. The gain of the active medium of electric-discharge OIL has been investigated. The DOIL in use was operating on a mix composed as O II:He=1:1 at a total pressure of 6 Torr and flowrate - about 1 mmol/s. With helium as an iodine carrier gas at a flowrate ~3 mmol/s, we have recorded a positive gain in the DOIL medium.

  3. Single photons from a gain medium below threshold

    NASA Astrophysics Data System (ADS)

    Ghosh, Sanjib; Liew, Timothy C. H.

    2018-06-01

    The emission from a nonlinear photonic mode coupled weakly to a gain medium operating below threshold is predicted to exhibit antibunching. In the steady state regime, analytical solutions for the relevant observable quantities are found in accurate agreement with exact numerical results. Under pulsed excitation, the unequal time second-order correlation function demonstrates the triggered probabilistic generation of single photons well separated in time.

  4. Yb:FAP and related materials, laser gain medium comprising same, and laser systems using same

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Krupke, William F.; Payne, Stephen A.; Chase, Lloyd L.

    An ytterbium doped laser material remarkably superior to all others, including Yb:YAG, comprises Ytterbium doped apatite (Yb:Ca.sub.5 (PO.sub.4).sub.3 F) or Yb:FAP, or ytterbium doped crystals that are structurally related to FAP. The new laser material is used in laser systems pumped by diode pump sources having an output near 0.905 microns or 0.98 microns, such as InGaAs and AlInGaAs, or other narrowband pump sources near 0.905 microns or 0.98 microns. The laser systems are operated in either the conventional or ground state depletion mode.

  5. Yb:FAP and related materials, laser gain medium comprising same, and laser systems using same

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Krupke, W.F.; Payne, S.A.; Chase, L.L.

    An ytterbium doped laser material remarkably superior to all others, including Yb:YAG, comprises ytterbium doped apatite (Yb:Ca{sub 5}(PO{sub 4}){sub 3}F) or Yb:FAP, or ytterbium doped crystals structurally related to FAP. The new laser material is used in laser systems pumped by diode pump sources having an output near 0.905 microns or 0.98 microns, such as InGaAs and AlInGaAs, or other narrowband pump sources near 0.905 microns or 0.98 microns. The laser systems are operated in either the conventional or ground state depletion mode.

  6. Yb:FAP and related materials, laser gain medium comprising same, and laser systems using same

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Krupke, W.F.; Payne, S.A.; Chase, L.L.

    An ytterbium doped laser material remarkably superior to all others, including Yb:YAG, comprises ytterbium doped apatite (Yb:Ca[sub 5](PO[sub 4])[sub 3]F) or Yb:FAP, or ytterbium doped crystals that are structurally related to FAP. The new laser material is used in laser systems pumped by diode pump sources having an output near 0.905 microns or 0.98 microns, such as InGaAs and AlInGaAs, or other narrowband pump sources near 0.905 microns or 0.98 microns. The laser systems are operated in either the conventional or ground state depletion mode. 9 figures.

  7. Yb:FAP and related materials, laser gain medium comprising same, and laser systems using same

    DOEpatents

    Krupke, W.F.; Payne, S.A.; Chase, L.L.; Smith, L.K.

    1994-01-18

    An ytterbium doped laser material remarkably superior to all others, including Yb:YAG, comprises ytterbium doped apatite (Yb:Ca[sub 5](PO[sub 4])[sub 3]F) or Yb:FAP, or ytterbium doped crystals that are structurally related to FAP. The new laser material is used in laser systems pumped by diode pump sources having an output near 0.905 microns or 0.98 microns, such as InGaAs and AlInGaAs, or other narrowband pump sources near 0.905 microns or 0.98 microns. The laser systems are operated in either the conventional or ground state depletion mode. 9 figures.

  8. Graphene plasmons embedded in a gain medium: layer and ribbon plasmons

    NASA Astrophysics Data System (ADS)

    Altares Menendez, Galaad; Rosolen, Gilles; Maes, Bjorn

    2016-12-01

    Graphene plasmonics has attracted much attention due to its remarkable properties such as tunable conductivity and extreme confinement. However, losses remain one of the major drawbacks to developing more efficient devices based on graphene plasmons. Here we show that when a gain medium is introduced around a 1D graphene sheet, lossless propagation can be achieved for a critical gain value. Both numerics and analytics are employed; and with the Drude approximation the analytical expression for this critical gain becomes remarkably simple. Furthermore, we examine a single 2D graphene nanoribbon within a gain environment. We report that the plasmonic resonant modes exhibit a spasing effect for a specific value of the surrounding gain. This feature is indicated by an absorption cross section that strongly increases and narrows. Finally, we manage to connect the ribbon results to the 1D sheet critical gain, by taking external coupling into account.

  9. Influence of wave-packet dynamics on the medium gain of an atomic system

    NASA Astrophysics Data System (ADS)

    Delagnes, J. C.; Bouchene, M. A.

    2007-10-01

    A sequence of two femtosecond pulses—a strong driving π -polarized pulse and a weak propagating σ -polarized pulse—excites resonantly the S1/2→P1/2 transition of an atomic system. Strong interference effects take place in the system between absorption and emission paths leading to a substantial amplification of the σ pulse. We study the influence of the fine structure on the medium gain when the contribution of the off-resonant P3/2 level is taken into account. A drastic reduction of the medium gain is obtained. This effect is explained within the bright-state dark-state formalism where the strong driving pulse creates a wave packet that can be trapped in a state—the bright state—leading to a significant reduction of the gain for the σ pulse. Finally, we also show that periodical gain dependence with the driving pulse energy exhibits a significant change in its period value (compared with expected Rabi oscillations).

  10. Analytical solution of the transient temperature profile in gain medium of passively Q-switched microchip laser.

    PubMed

    Han, Xiahui; Li, Jianlang

    2014-11-01

    The transient temperature evolution in the gain medium of a continuous wave (CW) end-pumped passively Q-switched microchip (PQSM) laser is analyzed. By approximating the time-dependent population inversion density as a sawtooth function of time and treating the time-dependent pump absorption of a CW end-pumped PQSM laser as the superposition of an infinite series of short pumping pulses, the analytical expressions of transient temperature evolution and distribution in the gain medium for four- and three-level laser systems, respectively, are given. These analytical solutions are applied to evaluate the transient temperature evolution and distribution in the gain medium of CW end-pumped PQSM Nd:YAG and Yb:YAG lasers.

  11. New results for temperature rise in gain medium of operating DPAL causing its degradation

    NASA Astrophysics Data System (ADS)

    Zhdanov, B. V.; Rotondaro, M. D.; Shaffer, M. K.; Knize, R. J.

    2017-10-01

    Diode Pumped Alkali Laser (DPAL) is one of the main candidates for development of a high power directed energy system producing laser beam from a single aperture with high spatial quality. Currently, several groups in the US and abroad demonstrated DPAL systems with kW level output power and efficiency higher than 50%. At the same time, the DPAL power scaling experiments revealed some limiting effects, which require detailed study to understand the nature of these effects and ways to mitigate them. Examples of such effects are output power degradation in time, alkali cell windows and gain medium contamination and damage that causes lasing efficiency decrease or even lasing termination. These problems can be connected to thermal effects, ionization, chemical interactions between the gain medium components and alkali cells materials. Study of all these and, possibly, other limiting effects and ways to mitigate them is very important for high power DPAL development. In this paper we present our new results of experiments on measurements of the temperature rise in the gain medium of operating DPAL leading to the output power degradation even before visible damage in the gain cell occurs. This degradation can be both recoverable and non-recoverable, depending on operation conditions and the system design.

  12. Method and system for edge cladding of laser gain media

    DOEpatents

    Bayramian, Andrew James; Caird, John Allyn; Schaffers, Kathleen Irene

    2014-03-25

    A gain medium operable to amplify light at a gain wavelength and having reduced transverse ASE includes an input surface and an output surface opposing the input surface. The gain medium also includes a central region including gain material and extending between the input surface and the output surface along a longitudinal optical axis of the gain medium. The gain medium further includes an edge cladding region surrounding the central region and extending between the input surface and the output surface along the longitudinal optical axis of the gain medium. The edge cladding region includes the gain material and a dopant operable to absorb light at the gain wavelength.

  13. Gain-adaptive vector quantization for medium-rate speech coding

    NASA Technical Reports Server (NTRS)

    Chen, J.-H.; Gersho, A.

    1985-01-01

    A class of adaptive vector quantizers (VQs) that can dynamically adjust the 'gain' of codevectors according to the input signal level is introduced. The encoder uses a gain estimator to determine a suitable normalization of each input vector prior to VQ coding. The normalized vectors have reduced dynamic range and can then be more efficiently coded. At the receiver, the VQ decoder output is multiplied by the estimated gain. Both forward and backward adaptation are considered and several different gain estimators are compared and evaluated. An approach to optimizing the design of gain estimators is introduced. Some of the more obvious techniques for achieving gain adaptation are substantially less effective than the use of optimized gain estimators. A novel design technique that is needed to generate the appropriate gain-normalized codebook for the vector quantizer is introduced. Experimental results show that a significant gain in segmental SNR can be obtained over nonadaptive VQ with a negligible increase in complexity.

  14. Toward the realization of erbium-doped GaN bulk crystals as a gain medium for high energy lasers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sun, Z. Y.; Li, J.; Zhao, W. P.

    Er-doped GaN (Er:GaN) is a promising candidate as a gain medium for solid-state high energy lasers (HELs) at the technologically important and eye-safe 1.54 μm wavelength window, as GaN has superior thermal properties over traditional laser gain materials such as Nd:YAG. However, the attainment of wafer-scale Er:GaN bulk or quasi-bulk crystals is a prerequisite to realize the full potential of Er:GaN as a gain medium for HELs. We report the realization of freestanding Er:GaN wafers of 2-in. in diameter with a thickness on the millimeter scale. These freestanding wafers were obtained via growth by hydride vapor phase epitaxy in conjunction withmore » a laser-lift-off process. An Er doping level of 1.4 × 10{sup 20} atoms/cm{sup 3} has been confirmed by secondary ion mass spectrometry measurements. The freestanding Er:GaN wafers exhibit strong photoluminescent emission at 1.54 μm with its emission intensity increasing dramatically with wafer thickness under 980 nm resonant excitation. A low thermal quenching of 10% was measured for the 1.54 μm emission intensity between 10 K and 300 K. This work represents a significant step in providing a practical approach for producing Er:GaN materials with sufficient thicknesses and dimensions to enable the design of gain media in various geometries, allowing for the production of HELs with improved lasing efficiency, atmosphere transmission, and eye-safety.« less

  15. Polymeric media comprising polybenzimidazoles N-substituted with organic-inorganic hybrid moiety

    DOEpatents

    Klaehn, John R [Idaho Falls, ID; Peterson, Eric S [Idaho Falls, ID; Wertsching, Alan K [Idaho Falls, ID; Orme, Christopher J [Shelley, ID; Luther, Thomas A [Idaho Falls, ID; Jones, Michael G [Pocatello, ID

    2009-12-15

    A PBI compound includes imidazole nitrogens at least a portion of which are substituted with an organic-inorganic hybrid moiety may be included in a separator medium. At least 85% of the imidazole nitrogens may be substituted. The organic-inorganic hybrid moiety may be an organosilane moiety, for example, (R)Me.sub.2SiCH.sub.2-- where R is selected from among methyl, phenyl, vinyl, and allyl. The separatory medium may exhibit an H.sub.2, Ar, N.sub.2, O.sub.2, CH.sub.3, or CO.sub.2 gas permeability greater than the gas permeability of a comparable separatory medium comprising the PBI compound without substitution. The separatory medium may further include an electronically conductive medium and/or ionically conductive medium. The separatory medium may be used as a membrane (semi-permeable, permeable, and non-permeable), a barrier, an ion exhcange media, a filter, a gas chromatography coating (such as stationary phase coating in affinity chromatography), etc.

  16. Wideband and flat-gain amplifier based on high concentration erbium-doped fibres in parallel double-pass configuration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hamida, B A; Cheng, X S; Harun, S W

    A wideband and flat gain erbium-doped fibre amplifier (EDFA) is demonstrated using a hybrid gain medium of a zirconiabased erbium-doped fibre (Zr-EDF) and a high concentration erbium-doped fibre (EDF). The amplifier has two stages comprising a 2-m-long ZEDF and 9-m-long EDF optimised for C- and L-band operations, respectively, in a double-pass parallel configuration. A chirp fibre Bragg grating (CFBG) is used in both stages to ensure double propagation of the signal and thus to increase the attainable gain in both C- and L-band regions. At an input signal power of 0 dBm, a flat gain of 15 dB is achievedmore » with a gain variation of less than 0.5 dB within a wide wavelength range from 1530 to 1605 nm. The corresponding noise figure varies from 6.2 to 10.8 dB within this wavelength region.« less

  17. RESONATORS. MODES: Modes of a plano - spherical laser resonator with the Gaussian gain distribution of the active medium

    NASA Astrophysics Data System (ADS)

    Malyutin, A. A.

    2007-03-01

    Modes of a laser with plano-spherical degenerate and nondegenerate resonators are calculated upon diode pumping producing the Gaussian gain distribution in the active medium. Axially symmetric and off-axis pumpings are considered. It is shown that in the first case the lowest Hermite-Gaussian mode is excited with the largest weight both in the degenerate and nondegenerate resonator if the pump level is sufficiently high or the characteristic size wg of the amplifying region greatly exceeds the mode radius w0. The high-order Ince-Gaussian modes are excited upon weak off-axis pumping in the nondegenerate resonator both in the absence and presence of the symmetry of the gain distribution with respect to the resonator axis. It is found that when the level of off-axis symmetric pumping of the resonator is high enough, modes with the parameters of the TEM00 mode periodically propagating over a closed path in the resonator can exist. The explanation of this effect is given.

  18. Doping-Induced Interband Gain in InAs/AlSb Quantum Wells

    NASA Technical Reports Server (NTRS)

    Kolokolov, K. I.; Ning, C. Z.

    2005-01-01

    A paper describes a computational study of effects of doping in a quantum well (QW) comprising a 10-nm-thick layer of InAs sandwiched between two 21-nm-thick AlSb layers. Heretofore, InAs/AlSb QWs have not been useful as interband gain devices because they have type-II energy-band-edge alignment, which causes spatial separation of electrons and holes, thereby leading to weak interband dipole matrix elements. In the doping schemes studied, an interior sublayer of each AlSb layer was doped at various total areal densities up to 5 X 10(exp 12) / square cm. It was found that (1) proper doping converts the InAs layer from a barrier to a well for holes, thereby converting the heterostructure from type II to type I; (2) the resultant dipole matrix elements and interband gains are comparable to those of typical type-I heterostructures; and (3) dipole moments and optical gain increase with the doping level. Optical gains in the transverse magnetic mode can be almost ten times those of other semiconductor material systems in devices used to generate medium-wavelength infrared (MWIR) radiation. Hence, doped InAs/AlSb QWs could be the basis of an alternative material system for devices to generate MWIR radiation.

  19. Holographic recording medium

    NASA Technical Reports Server (NTRS)

    Gange, Robert Allen (Inventor)

    1977-01-01

    A holographic recording medium comprising a conductive substrate, a photoconductive layer and an electrically alterable layer of a linear, low molecular weight hydrocarbon polymer has improved fatigue resistance. An acrylic barrier layer can be interposed between the photoconductive and electrically alterable layers.

  20. The influence of place on weight gain during early childhood: a population-based, longitudinal study.

    PubMed

    Carter, Megan Ann; Dubois, Lise; Tremblay, Mark S; Taljaard, Monica

    2013-04-01

    The objective of this paper was to determine the influence of place factors on weight gain in a contemporary cohort of children while also adjusting for early life and individual/family social factors. Participants from the Québec Longitudinal Study of Child Development comprised the sample for analysis (n = 1,580). A mixed-effects regression analysis was conducted to determine the longitudinal relationship between these place factors and standardized BMI, from age 4 to 10 years. The average relationship with time was found to be quadratic (rate of weight gain increased over time). Neighborhood material deprivation was found to be positively related to weight gain. Social deprivation, social disorder, and living in a medium density area were inversely related, while no association was found for social cohesion. Early life factors and genetic proxies appeared to be important in explaining weight gain in this sample. This study suggests that residential environments may play a role in childhood weight change; however, pathways are likely to be complex and interacting and perhaps not as important as early life factors and genetic proxies. Further work is required to clarify these relationships.

  1. Simulations on false gain in recombination-pumped soft-X-ray lasers

    NASA Astrophysics Data System (ADS)

    Ozaki, T.; Kuroda, H.

    1997-10-01

    Numerical investigations are performed on false gain due to axial plasma expansion, which is expected to be important in initial proof-of-principle studies of recombination-pumped soft-X-ray lasers with extended capabilities. Modelling calculations of experiments with slab boron nitride targets reveal large false gain coefficients approaching 20 cm-1 in the case of plasmas with short active medium lengths. The false gain in the case of fiber targets is found to be of equal magnitude to that for slabs in the case of plasmas with less than 0.1 cm active medium lengths. Calculations for slab targets predict that adopting a tolerance of ǃ cm-1 for gain will severely restrict the time and the active medium length of the plasma that can be used for error-free observations, while those for fiber targets are found to be considerably relaxed. The effects of false gain in the 54.2 + Na Balmer ! laser is also investigated, again revealing the importance of this phenomena under optimum gain conditions.

  2. Goos-Hänchen shifts of partially coherent light beams from a cavity with a four-level Raman gain medium

    NASA Astrophysics Data System (ADS)

    Ziauddin; Lee, Ray-Kuang; Qamar, Sajid

    2016-09-01

    We theoretically investigate spatial and angular Goos-Hänchen (GH) shifts (both negative and positive) in the reflected light for a partial coherent light incident on a cavity. A four-level Raman gain atomic medium is considered in a cavity. The effects of spatial coherence, beam width, and mode index of partial coherent light fields on spatial and angular GH shifts are studied. Our results reveal that a large magnitude of negative and positive GH shifts in the reflected light is achievable with the introduction of partial coherent light fields. Furthermore, the amplitude of spatial (negative and positive) GH shifts are sharply affected by the partial coherent light beam as compared to angular (negative and positive) GH shifts in the reflected light.

  3. Kinetics of the Active Medium of a Copper Vapor Brightness Amplifier

    NASA Astrophysics Data System (ADS)

    Kulagin, A. E.; Torgaev, S. N.; Evtushenko, G. S.; Trigub, M. V.

    2018-03-01

    A spatiotemporal kinetics of the active medium of a copper vapor brightness amplifier is described that allows gain characteristics to be investigated during the pump pulse. Model calculations show that changing the discharge parameters allows the radial gain profiles to be improved significantly, as well as the gain and the inversion duration to be increased. The data obtained will be used to choose the operating conditions for the active medium in the brightness amplifier mode.

  4. Method for inhibiting gum formation in liquid hydrocarbon mediums

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Reid, D.K.

    1990-07-17

    This patent describes a method of inhibiting the formation of gum and sediment in a liquid hydrocarbonaceous medium. It comprises: adding to the medium an inhibiting amount of an alkyl 1,2-dihydroquinoline or polymerized alkyl 1,2-dihydroquinoline.

  5. Extruder system and method for treatment of a gaseous medium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Silvi, Norberto; Perry, Robert James; Singh, Surinder Prabhjot

    A system for treatment of a gaseous medium, comprises an extruder having a barrel. The extruder further comprises a first inlet port, a second inlet port, and a plurality of outlet ports coupled to the barrel. The first inlet port is configured for feeding a lean sorbent, the second inlet port is configured for feeding a gaseous medium, and the plurality of outlet ports are configured for releasing a plurality of components removed from the gaseous medium. Further, the extruder comprises a plurality of helical elements coupled to a plurality of kneading elements, mounted on a shaft, and disposed withinmore » the barrel. The barrel and the plurality of helical and kneading elements together form an absorption unit and a desorption unit. The first and second inlet ports are formed in the absorption unit and the plurality of outlet ports are formed in the absorption and desorption units.« less

  6. Gain-phase modulation in chirped-pulse amplification

    NASA Astrophysics Data System (ADS)

    Shen, Yijie; Gao, Gan; Meng, Yuan; Fu, Xing; Gong, Mali

    2017-10-01

    The cross-modulation between the gain and chirped phase in chirped-pulse amplification (CPA) is theoretically and experimentally demonstrated. We propose a gain-phase coupled nonlinear Schrödinger equation (GPC-NLSE) for solving chirped-pulse propagation in a nonlinear gain medium involved in the gain-phase modulation (GPM) process. With the GPC-NLSE, the space-time-frequency-dependent gain, chirped phase, pulse, and spectrum evolutions can be precisely calculated. Moreover, a short-length high-gain Yb-doped fiber CPA experiment is presented in which a self-steepening distortion of the seed pulse is automatically compensated after amplification. This phenomenon can be explained by the GPM theory whereas conventional models cannot. The experimental results for the temporal and spectral intensities show excellent agreement with our theory. Our GPM theory paves the way for further investigations of the finer structures of the pulse and spectrum in CPA systems.

  7. Pulse generation without gain-bandwidth limitation in a laser with self-similar evolution.

    PubMed

    Chong, A; Liu, H; Nie, B; Bale, B G; Wabnitz, S; Renninger, W H; Dantus, M; Wise, F W

    2012-06-18

    With existing techniques for mode-locking, the bandwidth of ultrashort pulses from a laser is determined primarily by the spectrum of the gain medium. Lasers with self-similar evolution of the pulse in the gain medium can tolerate strong spectral breathing, which is stabilized by nonlinear attraction to the parabolic self-similar pulse. Here we show that this property can be exploited in a fiber laser to eliminate the gain-bandwidth limitation to the pulse duration. Broad (∼200 nm) spectra are generated through passive nonlinear propagation in a normal-dispersion laser, and these can be dechirped to ∼20-fs duration.

  8. Optical filter finesses enhancement based on nested coupled cavities and active medium

    NASA Astrophysics Data System (ADS)

    Adib, George A.; Sabry, Yasser M.; Khalil, Diaa

    2016-04-01

    Optical filters with relatively large FSR and narrow linewidth are simultaneously needed for different applications. The ratio between the FSR and the 3-dB linewidth is given by finesse of the filter, which is solely determined by the different energy loss mechanisms limited by the technology advancement. In this work, we present a novel coupled-cavity configuration embedding an optical filter and a gain medium; allowing an overall finesse enhancement and simultaneous FSR and 3-dB linewidth engineering beyond the technological limits of the filter fabrication method. The configuration consists of two resonators. An active ring resonator comprises an optical gain medium and a passive resonator. In one configuration, the optical filter is the passive resonator itself. In a second configuration, the passive resonator is another ring resonator that embeds the optical filter. The presented configurations using a semiconductor optical amplifier are applied one time to a mechanically Fabry-Perot filter in the first presented configuration; and a second time to a fiber ring filter in the second presented configuration. The mechanical filter has an original 3-dB linewidth of 1nm and an FSR that is larger than 100nm while the enhanced linewidth is about 0.3nm. The fiber ring filter length is 4 m and directional coupler ratios of 90/10corresponding to a 3-dBlinewidth of about 4MHz and an FSR of 47 MHz. The enhanced 3- dBlinewidth of the overall filter configuration is 200kHz, demonstrating finesse enhancement up to20 times the original finesse of the filter.

  9. Maximizing output power of a low-gain laser system.

    PubMed

    Carroll, D L; Sentman, L H

    1993-07-20

    Rigrod theory was used to model outcoupled power from a low-gain laser with good accuracy. For a low-gain overtone cw HF chemical laser, Rigrod theory shows that a higher medium saturation yields a higher overall overtone efficiency, but does not necessarily yield a higher measurable power (power in the bucket). For low-absorption-scattering loss overtone mirrors and a 5% penalty in outcoupled power, the intracavity flux and hence the mirror loading may be reduced by more than a factor of 2 when the gain length is long enough to saturate the medium well. For the University of Illinois at Urbana-Champaign overtone laser that has an extensive database with well-characterized mirrors for which the Rigrod parameters g(0) and I(sat) were firmly established, the accuracy to which the reflectivities of high-reflectivity overtone mirrors can be deduced by using measured mirror transmissivities, measured outcoupled power, and Rigrod theory is approximatly ±0.07%. This method of accurately deducing mirror reflectivities may be applicable to other low-gain laser systems that use high-reflectivity mirrors at different wavelengths. The maximum overtone efficiency is estimated to be approximately 80%-100%.

  10. Calculation of single-pass gain for laser ceramics with losses

    NASA Astrophysics Data System (ADS)

    Vatnik, S. M.

    2018-04-01

    Rate equations describing the single-pass gain in an active medium with losses are analytically solved. The found relations illustrate the dependences of the amplification efficiency of Nd : YAG ceramics on the pump power density and specific losses. It is concluded that specific losses can be estimated from comparative measurements of unsaturated and saturated gains.

  11. Energy Scaling of Nanosecond Gain-Switched Cr2+:ZnSe Lasers

    DTIC Science & Technology

    2011-01-01

    outcoupler or absorption from the lightly-doped active ions. Additionally, the edges of the crystals are cut at the Brewster angle , which raises...experiments we used Brewster cut Cr:ZnSe gain elements with a chromium concentration of 8x1018 cm-3. Under Cr:Tm:Ho:YAG pumping, the first Cr:ZnSe laser...the energy scaling of nanosecond gain-switched Cr:ZnSe lasers is optimization of the gain medium. In this study we used Brewster cut Cr:ZnSe gain

  12. Amplification and gas-dynamic parameters of the active oxygen-iodine medium produced by an ejector nozzle unit

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zagidullin, M V; Nikolaev, V D; Svistun, M I

    2001-08-31

    The gain, the temperature, and the absolute velocity of the supersonic active oxygen-iodine medium produced by an ejector nozzle unit were determined by the technique of high-resolution diode laser spectroscopy. The gain in the active medium is formed at less than 44 mm from the nozzle unit for an absolute flow velocity {nu} {approx} 600 m s{sup -1}. Upon dilution of oxygen by primary nitrogen in the ratio of 1 : 6.9, the gain of the active medium amounts to 7x10{sup -3} cm{sup -1}, the temperature of the active medium to 200 K, the absolute flow velocity to 580 mmore » s{sup -1}, and the pressure to 58 Torr. As the dilution is increased to 1 : 13.5, the gain reduces to 4.5x10{sup -3} cm{sup -1}, the temperature lowers to 180 K, the velocity of the active medium increases to 615 m s{sup -1}, and the pressure increases to 88 Torr. The increase in the initial content of water vapour in the oxygen flow results in an increase in the temperature and a decrease in the gain of the active medium. (active media)« less

  13. Information storage medium and method of recording and retrieving information thereon

    DOEpatents

    Marchant, D. D.; Begej, Stefan

    1986-01-01

    Information storage medium comprising a semiconductor doped with first and second impurities or dopants. Preferably, one of the impurities is introduced by ion implantation. Conductive electrodes are photolithographically formed on the surface of the medium. Information is recorded on the medium by selectively applying a focused laser beam to discrete regions of the medium surface so as to anneal discrete regions of the medium containing lattice defects introduced by the ion-implanted impurity. Information is retrieved from the storage medium by applying a focused laser beam to annealed and non-annealed regions so as to produce a photovoltaic signal at each region.

  14. Mechanism of the metallic metamaterials coupled to the gain material

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Huang, Zhixiang; Droulias, Sotiris; Koschny, Thomas

    2014-11-10

    In this study, we present evidence of strong coupling between the gain material and the metallic metamaterials. It is of vital importance to understand the mechanism of the coupling of metamaterials with the gain medium. Using a four-level gain system, the numerical pump-probe experiments are performed in several configurations (split–ring resonators (SRRs), inverse SRRs and fishnets) of metamaterials, demonstrating reduction of the resonator damping in all cases and hence the possibility for loss compensation. We find that the differential transmittance ΔT/T can be negative in different SRR configurations, such as SRRs on the top of the gain substrate, gain inmore » the SRR gap and gain covering the SRR structure, while in the fishnet metamaterial with gain ΔT/T is positive.« less

  15. Gain assisted nanocomposite multilayers with near zero permittivity modulus at visible frequencies

    NASA Astrophysics Data System (ADS)

    Rizza, Carlo; Di Falco, Andrea; Ciattoni, Alessandro

    2011-11-01

    We have fabricated a nano-laminate by alternating metal and gain medium layers, the gain dielectric consisting of a polymer incorporating optically pumped dye molecules. From standard reflection-transmission experiments, we show that, at a visible wavelength, both the real and the imaginary parts of the permittivity ɛ∥ attain very small values and we measure, at λ = 604 nm, |ɛ∥|=0.04 which is 21.5% smaller than its value in the absence of optical pumping. Our investigation thus proves that a medium with a permittivity with very small modulus, a key condition promising efficient subwavelength optical steering, can be actually synthesized.

  16. Cable Television...the Medium for Hispanics?

    ERIC Educational Resources Information Center

    Guernica, Antonio Jose

    1977-01-01

    Cable represents the only avenue available for Hispanics to gain substantial control over a communications medium. It has the potential to provide Hispanics not only with ownership opportunities, but also with employment, quality programming, and long-term commitments and responsibilities to meet the programming needs of the Hispanics in this…

  17. The Calibration of AVHRR/3 Visible Dual Gain Using Meteosat-8 as a MODIS Calibration Transfer Medium

    NASA Technical Reports Server (NTRS)

    Avey, Lance; Garber, Donald; Nguyen, Louis; Minnis, Patrick

    2007-01-01

    This viewgraph presentation reviews the NOAA-17 AVHRR visible channels calibrated against MET-8/MODIS using dual gain regression methods. The topics include: 1) Motivation; 2) Methodology; 3) Dual Gain Regression Methods; 4) Examples of Regression methods; 5) AVHRR/3 Regression Strategy; 6) Cross-Calibration Method; 7) Spectral Response Functions; 8) MET8/NOAA-17; 9) Example of gain ratio adjustment; 10) Effect of mixed low/high count FOV; 11) Monitor dual gains over time; and 12) Conclusions

  18. Red, green, and blue lasing enabled by single-exciton gain in colloidal quantum dot films

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nurmikko, Arto V.; Dang, Cuong

    The methods and materials described herein contemplate the use films of colloidal quantum dots as a gain medium in a vertical-cavity surface-emitting laser. The present disclosure demonstrates a laser with single-exciton gain in the red, green, and blue wavelengths. Leveraging this nanocomposite gain, the results realize a significant step toward full-color single-material lasers.

  19. Insulating Materials Comprising Polysilazane, Methods of Forming Such Insulating Materials, and Precursor Formulations Comprising Polysilazane

    NASA Technical Reports Server (NTRS)

    Larson, Robert S. (Inventor); Fuller, Michael E. (Inventor)

    2013-01-01

    Methods of forming an insulating material comprising combining a polysilazane, a cross-linking compound, and a gas-generating compound to form a reaction mixture, and curing the reaction mixture to form a modified polysilazane. The gas-generating compound may be water, an alcohol, an amine, or combinations thereof. The cross-linking compound may be an isocyanate, an epoxy resin, or combinations thereof. The insulating material may include a matrix comprising one of a reaction product of a polysilazane and an isocyanate and a reaction product of a polysilazane and an epoxy resin. The matrix also comprises a plurality of interconnected pores produced from one of reaction of the polysilazane and the isocyanate and from reaction of the polysilazane and the epoxy resin. A precursor formulation that comprises a polysilazane, a cross-linking compound, and a gas-generating compound is also disclosed.

  20. Compositions comprising free-standing two-dimensional nanocrystals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barsoum, Michel W.; Gogotsi, Yury; Abdelmalak, Michael Naguib

    2017-12-05

    The present invention is directed to methods of transferring urea from an aqueous solution comprising urea to a MXene composition, the method comprising contacting the aqueous solution comprising urea with the MXene composition for a time sufficient to form an intercalated MXene composition comprising urea.

  1. Subwavelength atom localization via coherent manipulation of the Raman gain process

    NASA Astrophysics Data System (ADS)

    Qamar, Sajid; Mehmood, Asad; Qamar, Shahid

    2009-03-01

    We present a simple scheme of atom localization in a subwavelength domain via manipulation of Raman gain process. We consider a four-level system with a pump and a weak probe field. In addition, we apply a coherent field to control the gain process. The system is similar to the one used by Agarwal and Dasgupta [Phys. Rev. A 70, 023802 (2004)] for the superluminal pulse propagation through Raman gain medium. For atom localization, we consider both pump and control fields to be the standing-wave fields of the cavity. We show that a much precise position of an atom passing through the standing-wave fields can be determined by measuring the gain spectrum of the probe field.

  2. Direct ink write fabrication of transparent ceramic gain media

    NASA Astrophysics Data System (ADS)

    Jones, Ivy Krystal; Seeley, Zachary M.; Cherepy, Nerine J.; Duoss, Eric B.; Payne, Stephen A.

    2018-01-01

    Solid-state laser gain media based on the garnet structure with two spatially distinct but optically contiguous regions have been fabricated. Transparent gain media comprised of a central core of Y2.97Nd0.03Al5.00O12.00 (Nd:YAG) and an undoped cladding region of Y3Al5O12 (YAG) were fabricated by direct ink write and transparent ceramic processing. Direct ink write (DIW) was employed to form the green body, offering a general route to preparing functionally structured solid-state laser gain media. Fully-dense transparent optical ceramics in a "top hat" geometry with YAG/Nd:YAG have been fabricated by DIW methods with optical scatter at 1064 nm of <3%/cm.

  3. Direct ink write fabrication of transparent ceramic gain media

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jones, Ivy Krystal; Seeley, Zachary M.; Cherepy, Nerine J.

    Solid-state laser gain media based on the garnet structure with two spatially distinct but optically contiguous regions have been fabricated. Transparent gain media comprised of a central core of Y 2.97Nd 0.03Al 5.00O 12.00 (Nd:YAG) and an undoped cladding region of Y 3Al 5O 12 (YAG) were fabricated by direct ink write and transparent ceramic processing. Direct ink write (DIW) was employed to form the green body, offering a general route to preparing functionally structured solid-state laser gain media. Lastly, fully-dense transparent optical ceramics in a “top hat” geometry with YAG/Nd:YAG have been fabricated by DIW methods with optical scattermore » at 1064 nm of <3%/cm.« less

  4. Direct ink write fabrication of transparent ceramic gain media

    DOE PAGES

    Jones, Ivy Krystal; Seeley, Zachary M.; Cherepy, Nerine J.; ...

    2018-11-06

    Solid-state laser gain media based on the garnet structure with two spatially distinct but optically contiguous regions have been fabricated. Transparent gain media comprised of a central core of Y 2.97Nd 0.03Al 5.00O 12.00 (Nd:YAG) and an undoped cladding region of Y 3Al 5O 12 (YAG) were fabricated by direct ink write and transparent ceramic processing. Direct ink write (DIW) was employed to form the green body, offering a general route to preparing functionally structured solid-state laser gain media. Lastly, fully-dense transparent optical ceramics in a “top hat” geometry with YAG/Nd:YAG have been fabricated by DIW methods with optical scattermore » at 1064 nm of <3%/cm.« less

  5. How should gestational weight gain be assessed? A comparison of existing methods and a novel method, area under the weight gain curve

    PubMed Central

    Kleinman, Ken P; Oken, Emily; Radesky, Jenny S; Rich-Edwards, Janet W; Peterson, Karen E; Gillman, Matthew W

    2007-01-01

    Background Gestational weight gain is important to assess for epidemiological and public health purposes: it is correlated with infant growth and may be related to maternal outcomes such as reproductive health and chronic disease risk. Methods commonly used to assess weight gain incorporate assumptions that are usually not borne out, such as a linear weight gain, or do not account for differential length of gestation. Methods We introduce a novel method to assess gestational weight gain, the area under the weight gain curve. This is easily interpretable as the additional pound-days carried due to pregnancy and avoids many flaws in alternative assessments. We compare the performance of the simple difference, weekly gain, Institute of Medicine categories and the area under the weight gain curve in predicting birthweight and maternal weight retention at 6, 12, 24 and 36 months post-partum. The analytic sample comprises 2016 participants in Project Viva, an observational prospective cohort study of pregnant women in Massachusetts. Results For birthweight outcomes, none of the weight gain measures is a meaningfully superior predictor. For 6-month postpartum weight retention the simple difference is superior, while for 12-, 24- and 36-month weight retention the area under the weight gain curve is superior. Conclusions These findings are plausible biologically: the same amount of weight gained early vs later in the pregnancy may reflect increased maternal fat stores. The timing of weight gain is reflected best in the area under the weight gain curve. Different methods of measuring gestational weight gain may be appropriate depending on the context. PMID:17715174

  6. Gain and losses in THz quantum cascade laser with metal-metal waveguide.

    PubMed

    Martl, Michael; Darmo, Juraj; Deutsch, Christoph; Brandstetter, Martin; Andrews, Aaron Maxwell; Klang, Pavel; Strasser, Gottfried; Unterrainer, Karl

    2011-01-17

    Coupling of broadband terahertz pulses into metal-metal terahertz quantum cascade lasers is presented. Mode matched terahertz transients are generated on the quantum cascade laser facet of subwavelength dimension. This method provides a full overlap of optical mode and active laser medium. A longitudinal optical-phonon depletion based active region design is investigated in a coupled cavity configuration. Modulation experiments reveal spectral gain and (broadband) losses. The observed gain shows high dynamic behavior when switching from loss to gain around threshold and is clamped at total laser losses.

  7. Gain enhancement with near-zero-index metamaterial superstrate

    NASA Astrophysics Data System (ADS)

    Bouzouad, M.; Chaker, S. M.; Bensafielddine, D.; Laamari, E. M.

    2015-11-01

    The objective of this paper was to use a near-zero-index ( n) metamaterial as a single- or a double-layer superstrate suspended above a microstrip patch antenna, operating at 43 GHz, for the gain enhancement. The single metamaterial layer superstrate consists of a periodic arrangement of Jerusalem cross unit cells and behaves as an homogeneous medium characterized by a refractive index close to zero. This metamaterial property allows gathering radiated waves from the antenna and collimates them toward the superstrate normal direction. The proposed design improves the antenna gain by 5.1 dB with the single-layer superstrate and 7 dB with the double-layer superstrate.

  8. Effects of Collaborative Group Composition and Inquiry Instruction on Reasoning Gains and Achievement in Undergraduate Biology

    PubMed Central

    Jensen, Jamie Lee; Lawson, Anton

    2011-01-01

    This study compared the effectiveness of collaborative group composition and instructional method on reasoning gains and achievement in college biology. Based on initial student reasoning ability (i.e., low, medium, or high), students were assigned to either homogeneous or heterogeneous collaborative groups within either inquiry or didactic instruction. Achievement and reasoning gains were assessed at the end of the semester. Inquiry instruction, as a whole, led to significantly greater gains in reasoning ability and achievement. Inquiry instruction also led to greater confidence and more positive attitudes toward collaboration. Low-reasoning students made significantly greater reasoning gains within inquiry instruction when grouped with other low reasoners than when grouped with either medium or high reasoners. Results are consistent with equilibration theory, supporting the idea that students benefit from the opportunity for self-regulation without the guidance or direction of a more capable peer. PMID:21364101

  9. Optofluidic lasers with a single molecular layer of gain

    PubMed Central

    Chen, Qiushu; Ritt, Michael; Sivaramakrishnan, Sivaraj; Sun, Yuze; Fan, Xudong

    2014-01-01

    We achieve optofluidic lasers with a single molecular layer of gain, in which green fluorescent protein, dye-labeled bovine serum albumin, and dye-labeled DNA are respectively used as the gain medium and attached to the surface of a ring resonator via surface immobilization biochemical methods. It is estimated that the surface density of the gain molecules is on the order of 1012/cm2, sufficient for lasing under pulsed optical excitation. It is further shown that the optofluidic laser can be tuned by energy transfer mechanisms through biomolecular interactions. This work not only opens a door to novel photonic devices that can be controlled at the level of a single molecular layer, but also provides a promising sensing platform to analyze biochemical processes at the solid-liquid interface. PMID:25312306

  10. Structured laser gain-medium by new bonding for power micro-laser

    NASA Astrophysics Data System (ADS)

    Kausas, Arvydas; Zheng, Lihe; Taira, Takunori

    2017-02-01

    In this work, we have compared the Q-switched performance of single rod crystal to a newly developed distributed face cooling structure. This structure was made by surface activated bonding technology and allowed to combine transparent heatsink to a gain crystal at room temperature. The Sapphire and Nd3+:YAG crystal plates were combined in this fashion to produce eight crystal chip which was further used to obtain Q-switch pulses with Cr4+:YAG crystal as saturable absorber. Energy of 9 mJ and pulse duration of 815 ps were achieved. Although the energy obtained with single rod system was 10 mJ, the degradation of the beam prevents such crystal to be used in further applications. This is the first demonstration of distributed face cooling system outperformed conventionally single rod system.

  11. How Pregnant African-American Women View Pregnancy Weight Gain

    PubMed Central

    Groth, Susan W.; Morrison-Beedy, Dianne; Meng, Ying

    2012-01-01

    Objective To gain insight into how low-income, pregnant African-American women viewed their weight gain while pregnant and how they managed their weight during pregnancy. Design Descriptive study using three focus groups. Setting Women were recruited from urban prenatal care sites and the Special Supplemental Nutrition Program for Women, Infants and Children (WIC) services in a medium-sized urban Northeastern city. Participants Twenty-six adult, low-income, pregnant African-American women, aged 18–39; the majority were within the first 20 weeks of pregnancy. Methods Three focus groups were conducted utilizing open-ended questions related to pregnancy weight gain. Content analysis was used to analyze the verbatim transcripts. Analysis focused on meaning, intention and context. Groups were compared and contrasted at the within and between group levels to identify themes. Results Four themes were identified that provided insight into how women viewed their pregnancy weight gain and managed weight gain during pregnancy: (a) pregnancy weight gain: no matter how much means a healthy baby; (b) weight retention: it happens; (c) there is a limit: weight gain impact on appearance; and (d) watching and waiting: plans for controlling weight. Conclusion Low-income African-American women, though cognizant of the likelihood of retention of weight following pregnancy, are not focused on limiting their gestational weight gain. The cultural acceptance of a larger body size along with the belief that gaining more weight is indicative of a healthy infant present challenges for interventions to limit excessive gestational weight gain. PMID:22789036

  12. Method for encapsulating and isolating hazardous cations, medium for encapsulating and isolating hazardous cations

    DOEpatents

    Wasserman, S.R.; Anderson, K.B.; Song, K.; Yuchs, S.E.; Marshall, C.L.

    1998-04-28

    A method for encapsulating hazardous cations is provided comprising supplying a pretreated substrate containing the cations; contacting the substrate with an organo-silane compound to form a coating on the substrate; and allowing the coating to cure. A medium for containing hazardous cations is also provided, comprising a substrate having ion-exchange capacity and a silane-containing coating on the substrate. 3 figs.

  13. Detection of gain enhancement in laser-induced fluorescence of rhodamine B lasing dye by silicon dioxide nanostructures-coated cavity

    NASA Astrophysics Data System (ADS)

    Al-Tameemi, Mohammed N. A.

    2018-03-01

    In this work, nanostructured silicon dioxide films are deposited by closed-field unbalanced direct-current (DC) reactive magnetron sputtering technique on two sides of quartz cells containing rhodamine B dye dissolved in ethanol with 10‒5 M concentration as a random gain medium. The preparation conditions are optimized to prepare highly pure SiO2 nanostructures with a minimum particle size of about 20 nm. The effect of SiO2 films as external cavity for the random gain medium is determined by the laser-induced fluorescence of this medium, and an increase of about 200% in intensity is observed after the deposition of nanostructured SiO2 thin films on two sides of the dye cell.

  14. Redesign of a Variable-Gain Output Feedback Longitudinal Controller Flown on the High-Alpha Research Vehicle (HARV)

    NASA Technical Reports Server (NTRS)

    Ostroff, Aaron J.

    1998-01-01

    This paper describes a redesigned longitudinal controller that flew on the High-Alpha Research Vehicle (HARV) during calendar years (CY) 1995 and 1996. Linear models are developed for both the modified controller and a baseline controller that was flown in CY 1994. The modified controller was developed with three gain sets for flight evaluation, and several linear analysis results are shown comparing the gain sets. A Neal-Smith flying qualities analysis shows that performance for the low- and medium-gain sets is near the level 1 boundary, depending upon the bandwidth assumed, whereas the high-gain set indicates a sensitivity problem. A newly developed high-alpha Bode envelope criterion indicates that the control system gains may be slightly high, even for the low-gain set. A large motion-base simulator in the United Kingdom was used to evaluate the various controllers. Desired performance, which appeared to be satisfactory for flight, was generally met with both the low- and medium-gain sets. Both the high-gain set and the baseline controller were very sensitive, and it was easy to generate pilot-induced oscillation (PIO) in some of the target-tracking maneuvers. Flight target-tracking results varied from level 1 to level 3 and from no sensitivity to PIO. These results were related to pilot technique and whether actuator rate saturation was encountered.

  15. Electrochemical energy storage devices comprising self-compensating polymers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Johnson, Paul; Bautista-Martinez, Jose Antonio; Friesen, Cody

    The disclosed technology relates generally to devices comprising conductive polymers and more particularly to electrochemical devices comprising self-compensating conductive polymers. In one aspect, electrochemical energy storage device comprises a negative electrode comprising an active material including a redox-active polymer. The device additionally comprises a positive electrode comprising an active material including a redox-active polymer. The device further comprises an electrolyte material interposed between the negative electrode and positive electrode and configured to conduct mobile counterions therethrough between the negative electrode and positive electrode. At least one of the negative electrode redox-active polymer and the positive electrode redox-active polymer comprises amore » zwitterionic polymer unit configured to reversibly switch between a zwitterionic state in which the zwitterionic polymer unit has first and second charge centers having opposite charge states that compensate each other, and a non-zwitterionic state in which the zwitterionic polymer unit has one of the first and second charge centers whose charge state is compensated by mobile counterions.« less

  16. Cationic electrodepositable coating composition comprising lignin

    DOEpatents

    Fenn, David; Bowman, Mark P; Zawacky, Steven R; Van Buskirk, Ellor J; Kamarchik, Peter

    2013-07-30

    A cationic electrodepositable coating composition is disclosed. The present invention in directed to a cationic electrodepositable coating composition comprising a lignin-containing cationic salt resin, that comprises (A) the reaction product of: lignin, an amine, and a carbonyl compound; (B) the reaction product of lignin, epichlorohydrin, and an amine; or (C) combinations thereof.

  17. Optical resonator and laser applications

    NASA Technical Reports Server (NTRS)

    Taghavi-Larigani, Shervin (Inventor); Vanzyl, Jakob J. (Inventor); Yariv, Amnon (Inventor)

    2006-01-01

    The invention discloses a semi-ring Fabry-Perot (SRFP) optical resonator structure comprising a medium including an edge forming a reflective facet and a waveguide within the medium, the waveguide having opposing ends formed by the reflective facet. The performance of the SRFP resonator can be further enhanced by including a Mach-Zehnder interferometer in the waveguide on one side of the gain medium. The optical resonator can be employed in a variety of optical devices. Laser structures using at least one SRFP resonator are disclosed where the resonators are disposed on opposite sides of a gain medium. Other laser structures employing one or more resonators on one side of a gain region are also disclosed.

  18. Optical resonator

    NASA Technical Reports Server (NTRS)

    Taghavi-Larigani, Shervin (Inventor); Vanzyl, Jakob J. (Inventor); Yariv, Amnon (Inventor)

    2006-01-01

    The invention discloses a semi-ring Fabry-Perot (SRFP) optical resonator structure comprising a medium including an edge forming a reflective facet and a waveguide within the medium, the waveguide having opposing ends formed by the reflective facet. The performance of the SRFP resonator can be further enhanced by including a Mach-Zehnder interferometer in the waveguide on one side of the gain medium. The optical resonator can be employed in a variety of optical devices. Laser structures using at least one SRFP resonator are disclosed where the resonators are disposed on opposite sides of a gain medium. Other laser structures employing one or more resonators on one side of a gain region are also disclosed.

  19. Long wavelength, high gain InAsSb strained-layer superlattice photoconductive detectors

    DOEpatents

    Biefeld, Robert M.; Dawson, L. Ralph; Fritz, Ian J.; Kurtz, Steven R.; Zipperian, Thomas E.

    1991-01-01

    A high gain photoconductive device for 8 to 12 .mu.m wavelength radiation including an active semiconductor region extending from a substrate to an exposed face, the region comprising a strained-layer superlattice of alternating layers of two different InAs.sub.1-x Sb.sub.x compounds having x>0.75. A pair of spaced electrodes are provided on the exposed face, and changes in 8 to 12 .mu.m radiation on the exposed face cause a large photoconductive gain between the spaced electrodes.

  20. Optoelectronic Instrument Monitors pH in a Culture Medium

    NASA Technical Reports Server (NTRS)

    Anderson, Melody M.; Pellis, Neal; Jeevarajan, Anthony S.; Taylor, Thomas D.

    2004-01-01

    An optoelectronic instrument monitors the pH of an aqueous cell-culture medium in a perfused rotating-wall-vessel bioreactor. The instrument is designed to satisfy the following requirements: It should be able to measure the pH of the medium continuously with an accuracy of 0.1 in the range from 6.5 to 7.5. It should be noninvasive. Any material in contact with the culture medium should be sterilizable as well as nontoxic to the cells to be grown in the medium. The biofilm that inevitably grows on any surface in contact with the medium should not affect the accuracy of the pH measurement. It should be possible to obtain accurate measurements after only one calibration performed prior to a bioreactor cell run. The instrument should be small and lightweight. The instrument includes a quartz cuvette through which the culture medium flows as it is circulated through the bioreactor. The cuvette is sandwiched between light source on one side and a photodetector on the other side. The light source comprises a red and a green light-emitting diode (LED) that are repeatedly flashed in alternation with a cycle time of 5 s. The responses of the photodiode to the green and red LEDs are processed electronically to obtain a quantity proportional to the ratio between the amounts of green and red light transmitted through the medium.

  1. VIIRS day-night band gain and offset determination and performance

    NASA Astrophysics Data System (ADS)

    Geis, J.; Florio, C.; Moyer, D.; Rausch, K.; De Luccia, F. J.

    2012-09-01

    On October 28th, 2011, the Visible-Infrared Imaging Radiometer Suite (VIIRS) was launched on-board the Suomi National Polar-orbiting Partnership (NPP) spacecraft. The instrument has 22 spectral bands: 14 reflective solar bands (RSB), 7 thermal emissive bands (TEB), and a Day Night Band (DNB). The DNB is a panchromatic, solar reflective band that provides visible through near infrared (IR) imagery of earth scenes with radiances spanning 7 orders of magnitude. In order to function over this large dynamic range, the DNB employs a focal plane array (FPA) consisting of three gain stages: the low gain stage (LGS), the medium gain stage (MGS), and the high gain stage (HGS). The final product generated from a DNB raw data record (RDR) is a radiance sensor data record (SDR). Generation of the SDR requires accurate knowledge of the dark offsets and gain coefficients for each DNB stage. These are measured on-orbit and stored in lookup tables (LUT) that are used during ground processing. This paper will discuss the details of the offset and gain measurement, data analysis methodologies, the operational LUT update process, and results to date including a first look at trending of these parameters over the early life of the instrument.

  2. Theory of lasing in a multiple-scattering medium

    NASA Astrophysics Data System (ADS)

    John, Sajeev; Pang, Gendi

    1996-10-01

    In several recent experiments, isotropic lasing action was observed in paints that contain rhodamine 640 dye molecules in methanol solution as gain media and titania particles as optical scatterers. These so-called paint-on laser systems are extraordinary because they are highly disordered systems. The microscopic mechanism for laser activity and the coherence properties of light emission in this multiple-light-scattering medium have not yet been elucidated. In this paper we derive the emission intensity properties of a model dye system with excited singlet and triplet electronic energy levels, which is immersed in a multiple-scattering medium with transport mean free path l*. Using physically reasonable estimates for the absorption and emission cross section for the singlet and triplet manifolds, and the singlet-triplet intersystem crossing rate, we solve the nonlinear laser rate equations for the dye molecules. This leads to a diffusion equation for the light intensity in the medium with a nonlinear intensity-dependent gain coefficient. Using this model we are able to account for nearly all of the experimentally observed properties of laser paint reported so far when l*>>λ0, the emission wavelength. This includes the dependence of the peak intensity of amplified emission on the mean free path l*, the dye concentration ρ, and the pump intensity characteristics. Our model recaptures the collapse of the emission linewidth at a specific threshold pump intensity and describes how this threshold intensity varies with l*. In addition, our model predicts a dramatic increase in the peak intensity and a further lowering of the lasing threshold for the strong scattering limit l*-->λ0. This suggests a striking enhancement of the characteristics of laser paint near the photon localization threshold in a disordered medium.

  3. High Average Power Laser Gain Medium With Low Optical Distortion Using A Transverse Flowing Liquid Host

    DOEpatents

    Comaskey, Brian J.; Ault, Earl R.; Kuklo, Thomas C.

    2005-07-05

    A high average power, low optical distortion laser gain media is based on a flowing liquid media. A diode laser pumping device with tailored irradiance excites the laser active atom, ion or molecule within the liquid media. A laser active component of the liquid media exhibits energy storage times longer than or comparable to the thermal optical response time of the liquid. A circulation system that provides a closed loop for mixing and circulating the lasing liquid into and out of the optical cavity includes a pump, a diffuser, and a heat exchanger. A liquid flow gain cell includes flow straighteners and flow channel compression.

  4. Effects of Developed Electronic Instructional Medium on Students' Achievement in Biology

    ERIC Educational Resources Information Center

    Chinna, Nsofor Caroline; Dada, Momoh Gabriel

    2013-01-01

    The study investigated the effects of developed electronic instructional medium (video DVD instructional package) on students' achievement in Biology. It was guided by two research questions and two hypotheses, using a quasi-experimental, pretest-postest control group design. The sample comprised of 180 senior secondary, year two students from six…

  5. Bistability in a hybrid optomechanical system: effect of a gain medium

    NASA Astrophysics Data System (ADS)

    Asghari Nejad, A.; Baghshahi, H. R.; Askari, H. R.

    2017-11-01

    In this paper, we investigate the optical bistability of a hybrid optomechanical system consisting of two coupled cavities: a bare optomechanical cavity (with an oscillating mirror at one end) and a traditional one. The traditional cavity is filled with an optical parametric amplifier (OPA), and an input pump laser is applied to it. The Hamiltonian of the system is written in a rotating frame. The dynamics of the system is driven by the quantum Langevin equations of motion. We demonstrate that the presence of an OPA can dramatically affect the type of stability of the optomechanical cavity. We show that it is possible to create a proper optical bistability for the optomechanical cavity by changing the gain coefficient of the OPA. Also, it is shown that changing the phase of the field driving the OPA has two different effects on the bistability region of the optomechanical cavity. Moreover, we show that by choosing a proper value for the detuning of the traditional cavity it is possible to observe a tristable behavior in the optomechanical cavity.

  6. Efficiency improvement of a concentrated solar receiver for water heating system using porous medium

    NASA Astrophysics Data System (ADS)

    Prasartkaew, Boonrit

    2018-01-01

    This experimental study aims at investigating on the performance of a high temperature solar water heating system. To approach the high temperature, a porous-medium concentrated solar collector equipped with a focused solar heliostat were proposed. The proposed system comprised of two parts: a 0.7x0.7-m2 porous medium receiver, was installed on a 3-m tower, and a focused multi-flat-mirror solar heliostat with 25-m2 aperture area. The porous medium used in this study was the metal swarf or metal waste from lathing process. To know how the system efficiency could be improved by using such porous medium, the proposed system with- and without-porous medium were tested and the comparative study was performed. The experimental results show that, using porous medium for enhancing the heat transfer mechanism, the system thermal efficiency was increased about 25%. It can be concluded that the efficiency of the proposed system can be substantially improved by using the porous medium.

  7. Laser amplifier and method

    DOEpatents

    Backus, S.; Kapteyn, H.C.; Murnane, M.M.

    1997-07-01

    Laser amplifiers and methods for amplifying a laser beam are disclosed. A representative embodiment of the amplifier comprises first and second curved mirrors, a gain medium, a third mirror, and a mask. The gain medium is situated between the first and second curved mirrors at the focal point of each curved mirror. The first curved mirror directs and focuses a laser beam to pass through the gain medium to the second curved mirror which reflects and recollimates the laser beam. The gain medium amplifies and shapes the laser beam as the laser beam passes therethrough. The third mirror reflects the laser beam, reflected from the second curved mirror, so that the laser beam bypasses the gain medium and return to the first curved mirror, thereby completing a cycle of a ring traversed by the laser beam. The mask defines at least one beam-clipping aperture through which the laser beam passes during a cycle. The gain medium is pumped, preferably using a suitable pumping laser. The laser amplifier can be used to increase the energy of continuous-wave or, especially, pulsed laser beams including pulses of femtosecond duration and relatively high pulse rate. 7 figs.

  8. Laser amplifier and method

    DOEpatents

    Backus, Sterling; Kapteyn, Henry C.; Murnane, Margaret M.

    1997-01-01

    Laser amplifiers and methods for amplifying a laser beam are disclosed. A representative embodiment of the amplifier comprises first and second curved mirrors, a gain medium, a third mirror, and a mask. The gain medium is situated between the first and second curved mirrors at the focal point of each curved mirror. The first curved mirror directs and focuses a laser beam to pass through the gain medium to the second curved mirror which reflects and recollimates the laser beam. The gain medium amplifies and shapes the laser beam as the laser beam passes therethough. The third mirror reflects the laser beam, reflected from the second curved mirror, so that the laser beam bypasses the gain medium and return to the first curved mirror, thereby completing a cycle of a ring traversed by the laser beam. The mask defines at least one beam-clipping aperture through which the laser beam passes during a cycle. The gain medium is pumped, preferably using a suitable pumping laser. The laser amplifier can be used to increase the energy of continuous-wave or, especially, pulsed laser beams including pulses of femtosecond duration and relatively high pulse rate.

  9. English-Medium Instruction in Japanese Universities: Policy Implementation and Constraints

    ERIC Educational Resources Information Center

    Chin Leong, Patrick N. G.

    2017-01-01

    English-medium instruction (EMI) is gaining momentum in Japan as politicians constantly highlight the need for Japanese universities to cultivate students with English skills to participate in the global market. Adopting a framework on the failure of policy implementation [Schiffman, H. (2007). Tamil language policy in Singapore. The role of…

  10. High-gain AlGaAs/GaAs double heterojunction Darlington phototransistors for optical neural networks

    NASA Technical Reports Server (NTRS)

    Kim, Jae H. (Inventor); Lin, Steven H. (Inventor)

    1991-01-01

    High-gain MOCVD-grown (metal-organic chemical vapor deposition) AlGaAs/GaAs/AlGaAs n-p-n double heterojunction bipolar transistors (DHBTs) and Darlington phototransistor pairs are provided for use in optical neural networks and other optoelectronic integrated circuit applications. The reduced base doping level used results in effective blockage of Zn out-diffusion, enabling a current gain of 500, higher than most previously reported values for Zn-diffused-base DHBTs. Darlington phototransitor pairs of this material can achieve a current gain of over 6000, which satisfies the gain requirement for optical neural network designs, which advantageously may employ neurons comprising the Darlington phototransistor pairs in series with a light source.

  11. Articles comprising ferritic stainless steels

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rakowski, James M.

    An article of manufacture comprises a ferritic stainless steel that includes a near-surface region depleted of silicon relative to a remainder of the ferritic stainless steel. The article has a reduced tendency to form an electrically resistive silica layer including silicon derived from the steel when the article is subjected to high temperature oxidizing conditions. The ferritic stainless steel is selected from the group comprising AISI Type 430 stainless steel, AISI Type 439 stainless steel, AISI Type 441 stainless steel, AISI Type 444 stainless steel, and E-BRITE.RTM. alloy, also known as UNS 44627 stainless steel. In certain embodiments, the articlemore » of manufacture is a fuel cell interconnect for a solid oxide fuel cell.« less

  12. Xylose utilizing Zymomonas mobilis with improved ethanol production in biomass hydrolysate medium

    DOEpatents

    Caimi, Perry G; Hitz, William D; Viitanen, Paul V; Stieglitz, Barry

    2013-10-29

    Xylose-utilizing, ethanol producing strains of Zymomonas mobilis with improved performance in medium comprising biomass hydrolysate were isolated using an adaptation process. Independently isolated strains were found to have independent mutations in the same coding region. Mutation in this coding may be engineered to confer the improved phenotype.

  13. Xylose utilizing zymomonas mobilis with improved ethanol production in biomass hydrolysate medium

    DOEpatents

    Caimi, Perry G; Hitz, William D; Stieglitz, Barry; Viitanen, Paul V

    2013-07-02

    Xylose-utilizing, ethanol producing strains of Zymomonas mobilis with improved performance in medium comprising biomass hydrolysate were isolated using an adaptation process. Independently isolated strains were found to have independent mutations in the same coding region. Mutation in this coding may be engineered to confer the improved phenotype.

  14. Coherent perfect absorption in a homogeneously broadened two-level medium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Longhi, Stefano

    2011-05-15

    In recent works, it has been shown, rather generally, that the time-reversed process of lasing at threshold realizes a coherent perfect absorber (CPA). In a CPA, a lossy medium in an optical cavity with a specific degree of dissipation, equal in modulus to the gain of the lasing medium, can perfectly absorb coherent optical waves that are the time-reversed counterpart of the lasing field. Here, the time-reversed process of lasing is considered in detail for a homogeneously broadened two-level medium in an optical cavity and the conditions for CPA are derived. It is shown that, owing to the dispersive propertiesmore » of the two-level medium, exact time-reversal symmetry is broken and the frequency of the field at which CPA occurs is generally different than the one of the lasing mode. Moreover, at a large cooperation parameter, the observation of CPA in the presence of bistability requires one to operate in the upper branch of the hysteresis cycle.« less

  15. Insulin and branched-chain amino acid depletion during mouse preimplantation embryo culture programmes body weight gain and raised blood pressure during early postnatal life.

    PubMed

    Velazquez, Miguel A; Sheth, Bhavwanti; Smith, Stephanie J; Eckert, Judith J; Osmond, Clive; Fleming, Tom P

    2018-02-01

    Mouse maternal low protein diet exclusively during preimplantation development (Emb-LPD) is sufficient to programme altered growth and cardiovascular dysfunction in offspring. Here, we use an in vitro model comprising preimplantation culture in medium depleted in insulin and branched-chain amino acids (BCAA), two proposed embryo programming inductive factors from Emb-LPD studies, to examine the consequences for blastocyst organisation and, after embryo transfer (ET), postnatal disease origin. Two-cell embryos were cultured to blastocyst stage in defined KSOM medium supplemented with four combinations of insulin and BCAA concentrations. Control medium contained serum insulin and uterine luminal fluid amino acid concentrations (including BCAA) found in control mothers from the maternal diet model (N-insulin+N-bcaa). Experimental medium (three groups) contained 50% reduction in insulin and/or BCAA (L-insulin+N-bcaa, N-insulin+L-bcaa, and L-insulin+N-bcaa). Lineage-specific cell numbers of resultant blastocysts were not affected by treatment. Following ET, a combined depletion of insulin and BCAA during embryo culture induced a non sex-specific increase in birth weight and weight gain during early postnatal life. Furthermore, male offspring displayed relative hypertension and female offspring reduced heart/body weight, both characteristics of Emb-LPD offspring. Combined depletion of metabolites also resulted in a strong positive correlation between body weight and glucose metabolism that was absent in the control group. Our results support the notion that composition of preimplantation culture medium can programme development and associate with disease origin affecting postnatal growth and cardiovascular phenotypes and implicate two important nutritional mediators in the inductive mechanism. Our data also have implications for human assisted reproductive treatment (ART) practice. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  16. Generation of 103 fs mode-locked pulses by a gain linewidth-variable Nd,Y:CaF2 disordered crystal.

    PubMed

    Qin, Z P; Xie, G Q; Ma, J; Ge, W Y; Yuan, P; Qian, L J; Su, L B; Jiang, D P; Ma, F K; Zhang, Q; Cao, Y X; Xu, J

    2014-04-01

    We have demonstrated a diode-pumped passively mode-locked femtosecond Nd,Y:CaF2 disordered crystal laser for the first time to our knowledge. By choosing appropriate Y-doping concentration, a broad fluorescence linewidth of 31 nm has been obtained from the gain linewidth-variable Nd,Y:CaF2 crystal. With the Nd,Y:CaF2 disordered crystal as gain medium, the mode-locked laser generated pulses with pulse duration as short as 103 fs, average output power of 89 mW, and repetition rate of 100 MHz. To our best knowledge, this is the shortest pulse generated from Nd-doped crystal lasers so far. The research results show that the Nd,Y:CaF2 disordered crystal will be a potential alternative as gain medium of repetitive chirped pulse amplification for high-peak-power lasers.

  17. Multi-level multi-thermal-electron FDTD simulation of plasmonic interaction with semiconducting gain media: applications to plasmonic amplifiers and nano-lasers.

    PubMed

    Chen, X; Bhola, B; Huang, Y; Ho, S T

    2010-08-02

    Interactions between a semiconducting gain medium and confined plasmon-polaritons are studied using a multilevel multi-thermal-electron finite-difference time-domain (MLMTE-FDTD) simulator. We investigated the amplification of wave propagating in a plasmonic metal-semiconductor-metal (MSM) waveguide filled with semiconductor gain medium and obtained the conditions required to achieve net optical gain. The MSM gain waveguide is used to form a plasmonic semiconductor nano-ring laser(PSNRL) with an effective mode volume of 0.0071 microm3, which is about an order of magnitude smaller than the smallest demonstrated integrated photonic crystal based laser cavities. The simulation shows a lasing threshold current density of 1kA/cm2 for a 300 nm outer diameter ring cavity with 80 nm-wide ring. This current density can be realistically achieved in typical III-V semiconductor, which shows the experimental feasibility of the proposed PSNRL structure.

  18. Resumption of gainful employment in aphasics: preliminary findings.

    PubMed

    Carriero, M R; Faglia, L; Vignolo, L A

    1987-12-01

    We report preliminary data on aphasic patients who, in spite of their language problems, have succeeded in finding a reasonably satisfactory occupational resettlement. Patients who: (a) still had a moderate to sever aphasia, (b) had resumed a gainful employment requiring interpersonal communication, were recalled for a check-up and assessed with: (1) a comprehensive aphasia test: (2) a semistructured interview including detailed questioning about the type and reaction to aphasia, the type of work before the onset of aphasia, the type of current work with particular emphasis on the patients' compensatory mechanisms and emotional reactions. Results comprise 10 cases up to date. One case is described in detail. Findings indicate that the ability to resume a gainful occupation is often greater than could be expected on the sole basis of formal language examination. Findings are discussed from a neuropsychological, social and rehabilitation point of view.

  19. Design of high-gain, wideband antenna using microwave hyperbolic metasurface

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhao, Yan, E-mail: yan.z@chula.ac.th

    In this work, we apply hyperbolic metasurfaces (HMSs) to design high-gain and wideband antennas. It is shown that HMSs formed by a single layer of split-ring resonators (SRRs) can be excited to generate highly directive beams. In particular, we suggest two types of the SRR-HMS: a capacitively loaded SRR (CLSRR)-HMS and a substrate-backed double SRR (DSRR)-HMS. Both configurations ensure that the periodicity of the structures is sufficiently small for satisfying the effective medium theory. For the antenna design, we propose a two-layer-stacked configuration for the 2.4 GHz frequency band based on the DSRR-HMS excited by a folded monopole. Measurement resultsmore » confirm numerical simulations and demonstrate that an antenna gain of more than 5 dBi can be obtained for the frequency range of 2.1 - 2.6 GHz, with a maximum gain of 7.8 dBi at 2.4 GHz.« less

  20. Sensor devices comprising field-structured composites

    DOEpatents

    Martin, James E.; Hughes, Robert C.; Anderson, Robert A.

    2001-02-27

    A new class of sensor devices comprising field-structured conducting composites comprising a textured distribution of conducting magnetic particles is disclosed. The conducting properties of such field-structured materials can be precisely controlled during fabrication so as to exhibit a large change in electrical conductivity when subject to any environmental influence which changes the relative volume fraction. Influences which can be so detected include stress, strain, shear, temperature change, humidity, magnetic field, electromagnetic radiation, and the presence or absence of certain chemicals. This behavior can be made the basis for a wide variety of sensor devices.

  1. Superluminal propagation in a poly-chromatically driven gain assisted four-level N-type atomic system

    NASA Astrophysics Data System (ADS)

    Amin Bacha, Bakht; Ahmad, Iftikhar; Ullah, Arif; Ali, Hazrat

    2013-10-01

    We investigate the behavior of light propagation in an N-type four-level gain assisted model (Agarwal and Dasgupta 2004 Phys. Rev. A 70 023802) under poly-chromatic pump fields. The system exhibits interesting results of multiple controllable pairs of the gain doublet profile with changes in the intensity of the control field. We observe multiple anomalous dispersive regions for superluminal propagation in the medium. A negative group velocity of -37.50 m s-1 with a negative time delay of -8 ms is observed between each gain doublet in anomalous dispersive regions. This generalized model and its predictions can be tested with existing experimental setups.

  2. Human body and head characteristics as a communication medium for Body Area Network.

    PubMed

    Kifle, Yonatan; Hun-Seok Kim; Yoo, Jerald

    2015-01-01

    An in-depth investigation of the Body Channel Communication (BCC) under the environment set according to the IEEE 802.15.6 Body Area Network (BAN) standard is conducted to observe and characterize the human body as a communication medium. A thorough measurement of the human head as part of the human channel is also carried out. Human forehead, head to limb, and ear to ear channel is characterized. The channel gain of the human head follows the same bandpass profile of the human torso and limbs with the maximum channel gain occurring at 35MHz. The human body channel gain distribution histogram at given frequencies, while all the other parameters are held constant, exhibits a maximum variation of 2.2dB in the channel gain at the center frequency of the bandpass channel gain profile.

  3. Strategies of Female Members of Parliament in Developing Empathy Values to Gain Constituent Support

    ERIC Educational Resources Information Center

    Ridhahani

    2017-01-01

    This qualitative research aims to describe the strategies applied by female parliamentary candidates to develop empathy values to gain constituent support in the legislative general election in 2014. Research subjects comprise 12 female members of parliament from seven regencies/cities in South Kalimantan who were chosen from different…

  4. Early Number Skills Gains and Mathematics Achievement: Intervening to Establish Successful Early Mathematics Trajectories

    ERIC Educational Resources Information Center

    Shanley, Lina; Clarke, Ben; Doabler, Christian T.; Kurtz-Nelson, Evangeline; Fien, Hank

    2017-01-01

    Early number skills, comprised of both informal and formal skills, are associated with later mathematics achievement. Thus, the development of foundational early number skills is an important aspect of early mathematics instruction. This study explored relations between early number skills gains and mathematics achievement for students at risk for…

  5. Ionization degree measurement in the gain medium of a hydrocarbon-free rubidium vapor laser operating in pulsed and CW modes.

    PubMed

    Zhao, Xiaofan; Yang, Zining; Hua, Weihong; Wang, Hongyan; Xu, Xiaojun

    2017-04-17

    Although the diode pumped alkali laser (DPAL) works in a three-level scheme, higher energy-state excitation and ionization processes exist during operation, which may lead to deleterious effects on laser performance. In this paper, we report the ionization degree measurement in the gain medium of an operational hydrocarbon-free Rb DPAL by using the optogalvanic method. The results show that, at the pulsed mode with a duration of ~1 ms, a maximal ionization degree of ~0.06% is obtained at a pump power of 140 W. While in the CW mode, the plasma reaches an ionization degree as high as ~2% at a pump power of 110 W, which is mainly due to the enough time for sufficient plasma development. A comparison with our previous work [Opt. Lett.39, 6501 (2014)] as well as modeling results is made and discussed. The influences of different population transfer channels on laser performance are simulated and analyzed. The results show that, for a typical hydrocarbon-free Rb laser (pump intensity of 15 kW/cm2, helium pressure of 10 atm and cell temperature of 438 K), all the high-energy excitation effects give an overall negative influence on laser efficiency of ~3.78%, while the top two influencing channels are the photoionization (~1.8%) and the energy pooling (~1.53%). The work in this paper experimentally reveals the influence of the macroscopic ionization evolution process on an operational DPAL for the first time, which would be helpful for a more comprehensive understanding of the physics in DPALs.

  6. Self-seeded single-frequency solid-state ring laser and system using same

    DOEpatents

    Dane, C. Brent; Hackel, Lloyd; Harris, Fritz B.

    2007-02-20

    A method of operating a laser to obtain an output pulse having a single wavelength, comprises inducing an intracavity loss into a laser resonator having an amount that prevents oscillation during a time that energy from the pump source is being stored in the gain medium. Gain is built up in the gain medium with energy from the pump source until formation of a single-frequency relaxation oscillation pulse in the resonator. Upon detection of the onset of the relaxation oscillation pulse, the intracavity loss is reduced, such as by Q-switching, so that the built-up gain stored in the gain medium is output from the resonator in the form of an output pulse at a single frequency. An electronically controllable output coupler is controlled to affect output pulse characteristics. The laser acts a master oscillator in a master oscillator power amplifier configuration. The laser is used for laser peening.

  7. Self-seeded single-frequency laser peening method

    DOEpatents

    Dane, C Brent [Livermore, CA; Hackel, Lloyd [Livermore, CA; Harris, Fritz B [Rocklin, CA

    2009-08-11

    A method of operating a laser to obtain an output pulse having a single wavelength, comprises inducing an intracavity loss into a laser resonator having an amount that prevents oscillation during a time that energy from the pump source is being stored in the gain medium. Gain is built up in the gain medium with energy from the pump source until formation of a single-frequency relaxation oscillation pulse in the resonator. Upon detection of the onset of the relaxation oscillation pulse, the intracavity loss is reduced, such as by Q-switching, so that the built-up gain stored in the gain medium is output from the resonator in the form of an output pulse at a single frequency. An electronically controllable output coupler is controlled to affect output pulse characteristics. The laser acts a master oscillator in a master oscillator power amplifier configuration. The laser is used for laser peening.

  8. Self-seeded single-frequency laser peening method

    DOEpatents

    DAne, C Brent; Hackey, Lloyd A; Harris, Fritz B

    2012-06-26

    A method of operating a laser to obtain an output pulse having a single wavelength, comprises inducing an intracavity loss into a laser resonator having an amount that prevents oscillation during a time that energy from the pump source is being stored in the gain medium. Gain is built up in the gain medium with energy from the pump source until formation of a single-frequency relaxation oscillation pulse in the resonator. Upon detection of the onset of the relaxation oscillation pulse, the intracavity loss is reduced, such as by Q-switching, so that the built-up gain stored in the gain medium is output from the resonator in the form of an output pulse at a single frequency. An electronically controllable output coupler is controlled to affect output pulse characteristics. The laser acts a master oscillator in a master oscillator power amplifier configuration. The laser is used for laser peening.

  9. Mode calculations in unstable resonators with flowing saturable gain. 1:hermite-gaussian expansion.

    PubMed

    Siegman, A E; Sziklas, E A

    1974-12-01

    We present a procedure for calculating the three-dimensional mode pattern, the output beam characteristics, and the power output of an oscillating high-power laser taking into account a nonuniform, transversely flowing, saturable gain medium; index inhomogeneities inside the laser resonator; and arbitrary mirror distortion and misalignment. The laser is divided into a number of axial segments. The saturated gain-and-index variation. across each short segment is lumped into a complex gain profile across the midplane of that segment. The circulating optical wave within the resonator is propagated from midplane to midplane in free-space fashion and is multiplied by the lumped complex gain profile upon passing through each midplane. After each complete round trip of the optical wave inside the resonator, the saturated gain profiles are recalculated based upon the circulating fields in the cavity. The procedure when applied to typical unstable-resonator flowing-gain lasers shows convergence to a single distorted steady-state mode of oscillation. Typical near-field and far-field results are presented. Several empirical rules of thumb for finite truncated Hermite-Gaussian expansions, including an approximate sampling theorem, have been developed as part of the calculations.

  10. Zymomonas with improved ethanol production in medium containing concentrated sugars and acetate

    DOEpatents

    Caimi, Perry G.; Chou, Yat-Chen; Franden, Mary Ann; Knoke, Kyle; Tao, Luan; Viitanen, Paul V.; Zhang, Min; Zhang, Yuying

    2010-09-28

    Through screening of a Zymomonas mutant library the himA gene was found to be involved in the inhibitory effect of acetate on Zymomonas performance. Xylose-utilizing Zymomonas further engineered to reduce activity of the himA gene were found to have increased ethanol production in comparison to a parental strain, when cultured in medium comprising xylose and acetate.

  11. Coated silicon comprising material for protection against environmental corrosion

    NASA Technical Reports Server (NTRS)

    Hazel, Brian Thomas (Inventor)

    2009-01-01

    In accordance with an embodiment of the invention, an article is disclosed. The article comprises a gas turbine engine component substrate comprising a silicon material; and an environmental barrier coating overlying the substrate, wherein the environmental barrier coating comprises cerium oxide, and the cerium oxide reduces formation of silicate glass on the substrate upon exposure to corrodant sulfates.

  12. The Social Context of Welsh-Medium Bilingual Education in Anglicised Areas.

    ERIC Educational Resources Information Center

    Bellin, Wynford; Farrell, Shaun; Higgs, Gary; White, Sean

    1999-01-01

    Principal component analysis of indicators from the 1991 Census was used to characterize the social context of school-age Welsh speakers in south east Wales. The growth of Welsh-medium education was responsible for net gains in numbers of younger Welsh/English bilinguals. The interrelationships between figures for Welsh speaking in the Census and…

  13. Ball bearings comprising nickel-titanium and methods of manufacture thereof

    NASA Technical Reports Server (NTRS)

    DellaCorte, Christopher (Inventor); Glennon, Glenn N. (Inventor)

    2012-01-01

    Disclosed herein is a friction reducing nickel-titanium composition. The nickel-titanium composition includes a first phase that comprises nickel and titanium in an atomic ratio of about 0.45:0.55 to about 0.55:0.45; a second phase that comprises nickel and titanium in an atomic ratio of about 0.70:0.30 to about 0.80:0.20; and a third phase that comprises nickel and titanium in an atomic ratio of about 0.52:0.48 to about 0.62:0.38. A bearing for reducing friction comprising a nickel-titanium composition comprising a first phase that comprises nickel and titanium in an atomic ratio of about 0.45:0.55 to about 0.55:0.45; a second phase that comprises nickel and titanium in an atomic ratio of about 0.70:0.30 to about 0.80:0.20; and a third phase that comprises nickel and titanium in an atomic ratio of about 0.52:0.48 to about 0.62:0.38; where the bearing is free from voids and pinholes.

  14. Holographic recording medium employing a photoconductive layer and a low molecular weight microcrystalline polymeric layer

    NASA Technical Reports Server (NTRS)

    Gange, Robert Allen (Inventor)

    1977-01-01

    A holographic recording medium comprising a conductive substrate, a photoconductive layer and an electrically alterable layer of a linear, low molecular weight hydrocarbon polymer has improved fatigue resistance. An acrylic barrier layer can be interposed between the photoconductive and electrically alterable layers.

  15. Gain dynamics of clad-pumped Yb-fiber amplifier and intensity noise control.

    PubMed

    Zhao, Jian; Guiraud, Germain; Floissat, Florian; Gouhier, Benoit; Rota-Rodrigo, Sergio; Traynor, Nicholas; Santarelli, Giorgio

    2017-01-09

    Gain dynamics study provides an attractive method to understand the intensity noise behavior in fiber amplifiers. Here, the gain dynamics of a medium power (5 W) clad-pumped Yb-fiber amplifier is experimentally evaluated by measuring the frequency domain transfer functions for the input seed and pump lasers from 10 Hz to 1 MHz. We study gain dynamic behavior of the fiber amplifier in the presence of significant residual pump power (compared to the seed power), showing that the seed transfer function is strongly saturated at low Fourier frequencies while the pump power modulation transfer function is nearly unaffected. The characterization of relative intensity noise (RIN) of the fiber amplifier is well explained by the gain dynamics analysis. Finally, a 600 kHz bandwidth feedback loop using an acoustic-optical modulator (AOM) controlling the seed intensity is successfully demonstrated to suppress the broadband laser intensity noise. A maximum noise reduction of about 30 dB is achieved leading to a RIN of -152 dBc/Hz (~1 kHz-10 MHz) at 2.5 W output power.

  16. Ionic liquids comprising heteraromatic anions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schneider, William F.; Brennecke, Joan F.; Maginn, Edward J.

    2018-04-24

    Some embodiments described herein relate to ionic liquids comprising an anion of a heteraromatic compound such as optionally substituted pyrrolide, optionally substituted pyrazolide, optionally substituted indolide, optionally substituted phospholide, or optionally substituted imidazolide. Methods and devices for gas separation or gas absorption related to these ionic liquids are also described herein.

  17. Compositions, methods, and systems comprising fluorous-soluble polymers

    DOEpatents

    Swager, Timothy M.; Lim, Jeewoo; Takeda, Yohei

    2015-10-13

    The present invention generally relates to compositions, methods, and systems comprising polymers that are fluorous-soluble and/or organize at interfaces between a fluorous phase and a non-fluorous phase. In some embodiments, emulsions or films are provided comprising a polymer. The polymers, emulsions, and films can be used in many applications, including for determining, treating, and/or imaging a condition and/or disease in a subject. The polymer may also be incorporated into various optoelectronic device such as photovoltaic cells, organic light-emitting diodes, organic field effect transistors, or the like. In some embodiments, the polymers comprise pi-conjugated backbones, and in some cases, are highly emissive.

  18. High-gain (43 dB), high-power (40 W), highly efficient multipass amplifier at 995 nm in Yb:LiYF4

    NASA Astrophysics Data System (ADS)

    Manni, Jeffrey; Harris, Dennis; Fan, Tso Yee

    2018-06-01

    A simple implementation of a multipass amplifier along with the use of a cryogenic Yb:LiYF4 (YLF) gain medium has enabled the demonstration of a bulk amplifier with an unprecedented combination of large-signal gain (43 dB), efficiency (>50% optical), average output power (40 W) and a near-diffraction-limited output beam.

  19. An improved medium for the anaerobic growth of Paracoccus denitrificans Pd1222

    PubMed Central

    Hahnke, Stefanie M.; Moosmann, Philipp; Erb, Tobias J.; Strous, Marc

    2014-01-01

    Paracoccus denitrificans is a well studied model organism with respect to its aerobic and anaerobic respiratory enzymes. However, until now, the growth medium for this organism has not been optimized for anaerobic growth. In particular, the requirements of P. denitrificans for trace elements (TEs) are not well known. In the present study we aimed to improve growth rates of P. denitrificans Pd1222 on a defined medium under anoxic conditions. We designed media containing different combinations of TEs at various concentrations, and tested their performance against previously reported media. Our results suggest that growth rate and yield depend on the availability and concentration of TEs in the medium. A chelated TE solution was more suitable than an acidified TE solution. Highest growth rates were achieved with medium comprising the TEs iron, manganese, molybdenum, copper and zinc ranging from 0.1 to 9 μM. On this medium, P. denitrificans Pd1222 grew with a generation time of 4.4 h under anoxic conditions and 2.8 h under oxic conditions. Diauxic growth was clearly shown with respect to nitrate and nitrite reduction under anoxic conditions. PMID:24550891

  20. An improved medium for the anaerobic growth of Paracoccus denitrificans Pd1222.

    PubMed

    Hahnke, Stefanie M; Moosmann, Philipp; Erb, Tobias J; Strous, Marc

    2014-01-01

    Paracoccus denitrificans is a well studied model organism with respect to its aerobic and anaerobic respiratory enzymes. However, until now, the growth medium for this organism has not been optimized for anaerobic growth. In particular, the requirements of P. denitrificans for trace elements (TEs) are not well known. In the present study we aimed to improve growth rates of P. denitrificans Pd1222 on a defined medium under anoxic conditions. We designed media containing different combinations of TEs at various concentrations, and tested their performance against previously reported media. Our results suggest that growth rate and yield depend on the availability and concentration of TEs in the medium. A chelated TE solution was more suitable than an acidified TE solution. Highest growth rates were achieved with medium comprising the TEs iron, manganese, molybdenum, copper and zinc ranging from 0.1 to 9 μM. On this medium, P. denitrificans Pd1222 grew with a generation time of 4.4 h under anoxic conditions and 2.8 h under oxic conditions. Diauxic growth was clearly shown with respect to nitrate and nitrite reduction under anoxic conditions.

  1. Gain-assisted broadband ring cavity enhanced spectroscopy

    NASA Astrophysics Data System (ADS)

    Selim, Mahmoud A.; Adib, George A.; Sabry, Yasser M.; Khalil, Diaa

    2017-02-01

    Incoherent broadband cavity enhanced spectroscopy can significantly increase the effective path length of light-matter interaction to detect weak absorption lines over broad spectral range, for instance to detect gases in confined environments. Broadband cavity enhancement can be based on the decay time or the intensity drop technique. Decay time measurement is based on using tunable laser source that is expensive and suffers from long scan time. Intensity dependent measurement is usually reported based on broadband source using Fabry-Perot cavity, enabling short measurement time but suffers from the alignment tolerance of the cavity and the cavity insertion loss. In this work we overcome these challenges by using an alignment-free ring cavity made of an optical fiber loop and a directional coupler, while having a gain medium pumped below the lasing threshold to improve the finesse and reduce the insertion loss. Acetylene (C2H2) gas absorption is measured around 1535 nm wavelength using a semiconductor optical amplifier (SOA) gain medium. The system is analyzed for different ring resonator forward coupling coefficient and loses, including the 3-cm long gas cell insertion loss and fiber connector losses used in the experimental verification. The experimental results are obtained for a coupler ratio of 90/10 and a fiber length of 4 m. The broadband source is the amplified spontaneous emission of another SOA and the output is measured using a 70pm-resolution optical spectrum analyzer. The absorption depth and the effective interaction length are improved about an order of magnitude compared to the direct absorption of the gas cell. The presented technique provides an engineering method to improve the finesse and, consequently the effective length, while relaxing the technological constraints on the high reflectivity mirrors and free-space cavity alignment.

  2. Distributed gain in plasmonic reflectors and its use for terahertz generation.

    PubMed

    Sydoruk, O; Syms, R R A; Solymar, L

    2012-08-27

    Semiconductor plasmons have potential for terahertz generation. Because practical device formats may be quasi-optical, we studied theoretically distributed plasmonic reflectors that comprise multiple interfaces between cascaded two-dimensional electron channels. Employing a mode-matching technique, we show that transmission through and reflection from a single interface depend on the magnitude and direction of a dc current flowing in the channels. As a result, plasmons can be amplified at an interface, and the cumulative effect of multiple interfaces increases the total gain, leading to plasmonic reflection coefficients exceeding unity. Reversing the current direction in a distributed reflector, however, has the opposite effect of plasmonic deamplification. Consequently, we propose structurally asymmetric resonators comprising two different distributed reflectors and predict that they are capable of terahertz oscillations at low threshold currents.

  3. Electrochemical Device Comprising an Electrically-Conductive, Selectively-Permeable Membrane

    NASA Technical Reports Server (NTRS)

    Laicer, Castro S. T. (Inventor); Mittelsteadt, Cortney K. (Inventor); Harrison, Katherine E. (Inventor); McPheeters, Bryn M. (Inventor)

    2017-01-01

    An electrochemical device, such as a fuel cell or an electrolyzer. In one embodiment, the electrochemical device includes a membrane electrode assembly (MEA), an anodic gas diffusion medium in contact with the anode of the MEA, a cathodic gas diffusion medium in contact with the cathode, a first bipolar plate in contact with the anodic gas diffusion medium, and a second bipolar plate in contact with the cathodic gas diffusion medium. Each of the bipolar plates includes an electrically-conductive, non-porous, liquid-permeable, substantially gas-impermeable membrane in contact with its respective gas diffusion medium, the membrane including a solid polymer electrolyte and a non-particulate, electrically-conductive material, such as carbon nanotubes, carbon nanofibers, and/or metal nanowires. In addition, each bipolar plate also includes an electrically-conductive fluid chamber in contact with the electrically-conductive, selectively-permeable membrane and further includes a non-porous and electrically-conductive plate in contact with the fluid chamber.

  4. Sound pressure level gain in an acoustic metamaterial cavity.

    PubMed

    Song, Kyungjun; Kim, Kiwon; Hur, Shin; Kwak, Jun-Hyuk; Park, Jihyun; Yoon, Jong Rak; Kim, Jedo

    2014-12-11

    The inherent attenuation of a homogeneous viscous medium limits radiation propagation, thereby restricting the use of many high-frequency acoustic devices to only short-range applications. Here, we design and experimentally demonstrate an acoustic metamaterial localization cavity which is used for sound pressure level (SPL) gain using double coiled up space like structures thereby increasing the range of detection. This unique behavior occurs within a subwavelength cavity that is 1/10(th) of the wavelength of the incident acoustic wave, which provides up to a 13 dB SPL gain. We show that the amplification results from the Fabry-Perot resonance of the cavity, which has a simultaneously high effective refractive index and effective impedance. We also experimentally verify the SPL amplification in an underwater environment at higher frequencies using a sample with an identical unit cell size. The versatile scalability of the design shows promising applications in many areas, especially in acoustic imaging and underwater communication.

  5. Sound Pressure Level Gain in an Acoustic Metamaterial Cavity

    PubMed Central

    Song, Kyungjun; Kim, Kiwon; Hur, Shin; Kwak, Jun-Hyuk; Park, Jihyun; Yoon, Jong Rak; Kim, Jedo

    2014-01-01

    The inherent attenuation of a homogeneous viscous medium limits radiation propagation, thereby restricting the use of many high-frequency acoustic devices to only short-range applications. Here, we design and experimentally demonstrate an acoustic metamaterial localization cavity which is used for sound pressure level (SPL) gain using double coiled up space like structures thereby increasing the range of detection. This unique behavior occurs within a subwavelength cavity that is 1/10th of the wavelength of the incident acoustic wave, which provides up to a 13 dB SPL gain. We show that the amplification results from the Fabry-Perot resonance of the cavity, which has a simultaneously high effective refractive index and effective impedance. We also experimentally verify the SPL amplification in an underwater environment at higher frequencies using a sample with an identical unit cell size. The versatile scalability of the design shows promising applications in many areas, especially in acoustic imaging and underwater communication. PMID:25502279

  6. Postnatal Weight Gain Modifies Severity and Functional Outcome of Oxygen-Induced Proliferative Retinopathy

    PubMed Central

    Stahl, Andreas; Chen, Jing; Sapieha, Przemyslaw; Seaward, Molly R.; Krah, Nathan M.; Dennison, Roberta J.; Favazza, Tara; Bucher, Felicitas; Löfqvist, Chatarina; Ong, Huy; Hellström, Ann; Chemtob, Sylvain; Akula, James D.; Smith, Lois E.H.

    2010-01-01

    In clinical studies, postnatal weight gain is strongly associated with retinopathy of prematurity (ROP). However, animal studies are needed to investigate the pathophysiological mechanisms of how postnatal weight gain affects the severity of ROP. In the present study, we identify nutritional supply as one potent parameter that affects the extent of retinopathy in mice with identical birth weights and the same genetic background. Wild-type pups with poor postnatal nutrition and poor weight gain (PWG) exhibit a remarkably prolonged phase of retinopathy compared to medium weight gain or extensive weight gain pups. A high (r2 = 0.83) parabolic association between postnatal weight gain and oxygen-induced retinopathy severity is observed, as is a significantly prolonged phase of proliferative retinopathy in PWG pups (20 days) compared with extensive weight gain pups (6 days). The extended retinopathy is concomitant with prolonged overexpression of retinal vascular endothelial growth factor in PWG pups. Importantly, PWG pups show low serum levels of nonfasting glucose, insulin, and insulin-like growth factor-1 as well as high levels of ghrelin in the early postoxygen-induced retinopathy phase, a combination indicative of poor metabolic supply. These differences translate into visual deficits in adult PWG mice, as demonstrated by impaired bipolar and proximal neuronal function. Together, these results provide evidence for a pathophysiological correlation between poor postnatal nutritional supply, slow weight gain, prolonged retinal vascular endothelial growth factor overexpression, protracted retinopathy, and reduced final visual outcome. PMID:21056995

  7. Postnatal weight gain modifies severity and functional outcome of oxygen-induced proliferative retinopathy.

    PubMed

    Stahl, Andreas; Chen, Jing; Sapieha, Przemyslaw; Seaward, Molly R; Krah, Nathan M; Dennison, Roberta J; Favazza, Tara; Bucher, Felicitas; Löfqvist, Chatarina; Ong, Huy; Hellström, Ann; Chemtob, Sylvain; Akula, James D; Smith, Lois E H

    2010-12-01

    In clinical studies, postnatal weight gain is strongly associated with retinopathy of prematurity (ROP). However, animal studies are needed to investigate the pathophysiological mechanisms of how postnatal weight gain affects the severity of ROP. In the present study, we identify nutritional supply as one potent parameter that affects the extent of retinopathy in mice with identical birth weights and the same genetic background. Wild-type pups with poor postnatal nutrition and poor weight gain (PWG) exhibit a remarkably prolonged phase of retinopathy compared to medium weight gain or extensive weight gain pups. A high (r(2) = 0.83) parabolic association between postnatal weight gain and oxygen-induced retinopathy severity is observed, as is a significantly prolonged phase of proliferative retinopathy in PWG pups (20 days) compared with extensive weight gain pups (6 days). The extended retinopathy is concomitant with prolonged overexpression of retinal vascular endothelial growth factor in PWG pups. Importantly, PWG pups show low serum levels of nonfasting glucose, insulin, and insulin-like growth factor-1 as well as high levels of ghrelin in the early postoxygen-induced retinopathy phase, a combination indicative of poor metabolic supply. These differences translate into visual deficits in adult PWG mice, as demonstrated by impaired bipolar and proximal neuronal function. Together, these results provide evidence for a pathophysiological correlation between poor postnatal nutritional supply, slow weight gain, prolonged retinal vascular endothelial growth factor overexpression, protracted retinopathy, and reduced final visual outcome.

  8. The Dynamics of Supply and Demand Chain of English-Medium Schools in Bangladesh

    ERIC Educational Resources Information Center

    Mousumi, Manjuma Akhtar; Kusakabe, Tatsuya

    2017-01-01

    This research concerns English-medium schools (EMSs), which are emerging as a popular new educational sector in Bangladesh. Because these schools have gained immense popularity, we seek to identify how these schools respond to parental demand and retain their clientele. In addition to English language demand, our findings reveal a symmetrical…

  9. College Freshmen Students’ Perspectives on Weight Gain Prevention in the Digital Age: Web-Based Survey

    PubMed Central

    Turner-McGrievy, Gabrielle; Larsen, Chelsea A; Magradey, Karen; Brandt, Heather M; Wilcox, Sara; Sundstrom, Beth; West, Delia Smith

    2017-01-01

    Background College freshmen are highly vulnerable to experiencing weight gain, and this phenomenon is associated with an increased risk of chronic diseases and mortality in older adulthood. Technology offers an attractive and scalable way to deliver behavioral weight gain prevention interventions for this population. Weight gain prevention programs that harness the appeal and widespread reach of Web-based technologies (electronic health or eHealth) are increasingly being evaluated in college students. Yet, few of these interventions are informed by college students’ perspectives on weight gain prevention and related lifestyle behaviors. Objective The objective of this study was to assess college freshmen students’ concern about weight gain and associated topics, as well as their interest in and delivery medium preferences for eHealth programs focused on these topics. Methods Web-based surveys that addressed college freshmen students’ (convenience sample of N=50) perspectives on weight gain prevention were administered at the beginning and end of the fall 2015 semester as part of a longitudinal investigation of health-related issues and experiences in first semester college freshmen. Data on weight gain prevention-related concerns and corresponding interest in eHealth programs targeting topics of potential concern, as well as preferred program delivery medium and current technology use were gathered and analyzed using descriptive statistics. Results A considerable proportion of the freshmen sample expressed concern about weight gain (74%, 37/50) and both traditional (healthy diet: 86%, 43/50; physical activity: 64%, 32/50) and less frequently addressed (stress: 82%, 41/50; sleep: 74%, 37/50; anxiety and depression: 60%, 30/50) associated topics within the context of behavioral weight gain prevention. The proportion of students who reported interest in eHealth promotion programs targeting these topics was also generally high (ranging from 52% [26/50] for stress

  10. Active metamaterial: Gain and stability, and microfluidic chip for THz cell spectroscopy

    NASA Astrophysics Data System (ADS)

    Tang, Qi

    Metamaterials are artificially designed composite materials which can exhibit unique and unusual properties such as the negative refractive index, negative phase velocity, etc. The concept of metamaterials becomes prevalent in the electromagnetic society since the first experimental implementation in the early 2000s. Many fascinated potential applications, e.g. super lens, invisibility cloaking, and novel antennas that are electrically small, have been proposed based on metamaterials. However, most of the applications still remain in theory and are not suitable for practical applications mainly due to the intrinsic loss and narrow bandwidth (large dispersion) determined by the fundamental physics of metamaterials. In this dissertation, we incorporate active gain devices into conventional passive metamaterials to overcome loss and even provide gain. Two types of active gain negative refractive index metamaterials are proposed, designed and experimentally demonstrated, including an active composite left-/right-handed transmission line and an active volumetric metamaterial. In addition, we investigate the non-Foster circuits for broadband matching of electrically small antennas. A rigorous way of analyzing the stability of non-Foster circuits by normalized determinant function is proposed. We study the practical factors that may affect the stability of non-Foster circuits, including the device parasitics, DC biasing, layouts and load impedance. A stable floating negative capacitor is designed, fabricated and tested. Moreover, it is important to resolve the sign of refractive index for active gain media which can be quite challenging. We investigate the analytical solution of a gain slab system, and apply the Nyquist criterion to analyze the stability of a causal gain medium. We then emphasize that the result of frequency domain simulation has to be treated with care. Lastly, this dissertation discusses another interesting topic about THz spectroscopy of live cells

  11. Zymomonas with improved ethanol production in medium containing concentrated sugars and acetate

    DOEpatents

    Caimi, Perry G [Kennett Square, PA; Chou, Yat-Chen [Lakewood, CO; Franden, Mary Ann [Centennial, CO; Knoke, Kyle [Newark, DE; Tao, Luan [Havertown, PA; Viitanen, Paul V [West Chester, PA; Zhang, Min [Lakewood, CO; Zhang, Yuying [New Hope, PA

    2011-03-01

    Through screening of a Zymomonas mutant library the himA gene was found to be involved in the inhibitory effect of acetate on Zymomonas performance. Xylose-utilizing Zymomonas strains further engineered to reduce activity of the himA gene were found to have increased ethanol production in comparison to a parental strain, when cultured in mixed-sugars medium comprising xylose, and, in particular, in the presence of acetate.

  12. Challenges in English Medium of Instruction from the Teachers and Students' Eyes

    ERIC Educational Resources Information Center

    Cankaya, Pinar

    2017-01-01

    The main concern of the current paper is to discuss English medium instruction (EMI, henceforth) in all aspects with a particular focus on its challenges and difficulties reported by both students and teachers based on the relevant research studies. As EMI is gaining greatest importance among the researchers, policy makers and educators; it is of…

  13. Compositions Comprising Nickel-Titanium, Methods Manufacture Thereof and Articles Comprising the Same

    NASA Technical Reports Server (NTRS)

    DellaCorte, Christopher (Inventor); Glennon, Glenn N. (Inventor)

    2016-01-01

    Disclosing herein is a method for manufacturing nickel-titanium compositions. The method includes disposing a powdered composition in a mold; the powdered composition comprising nickel and titanium; the titanium being present in an amount of about 38 to about 42 wt % and the nickel being present in an amount of about 58 to about 62 wt %; sintering the powdered composition to produce a sintered preform; compacting the preform; machining the preform to form an article; heat treating the article; the annealing being conducted at a temperature of about 1650.degree. F. to about 1900.degree. F. at a pressure of about 3 Torr to about 5 Kg-f/cm.sup.2 for a time period of about 10 minutes to about 5 hours; and quenching the article.

  14. A comparison of the original Rappaport medium (R medium) and the Rappaport-Vassiliadis medium (RV medium) in the isolation of salmonellae from meat products.

    PubMed Central

    Vassiliadis, P.; Kalapothaki, V.; Mavrommati, C.; Trichopoulos, D.

    1984-01-01

    The Rappaport-Vassiliadis enrichment medium (RV medium) in 10 ml quantities (RV/43 degrees C, 10 ml) inoculated with 0.1 ml of pre-enrichment medium (P medium) was found more efficient in the isolation of salmonellae from 409 pre-enriched samples (mainly meat products), than the original Rappaport medium incubated at 43 degrees C (R/43 degrees C) and the RV medium in 5 ml quantities (RV/43 degrees C, 5 ml) inoculated with 0.01 ml of P medium (P less than 0.001, in both instances). Therefore, the inoculum from pre-enriched foods should not be less than 0.1 ml in 10 ml of RV medium. The RV/43 degrees, 10 ml was also better (P less than 0.01) in detecting samples containing salmonellas than the original Rappaport medium incubated at 37 degrees C (R/37 degrees C, 10 ml) and the modification R25 of R medium incubated at 37 degrees C. The R25 modification was used in 10 ml quantities (R25/37 degrees C, 10 ml) inoculated with 0.1 ml of P medium and in 5 ml quantities (R25/37 degrees, 5 ml) inoculated with 0.01 ml of P medium. The last two R25 procedures were of the same efficiency in isolating salmonellas from meat products. PMID:6747286

  15. High power regenerative laser amplifier

    DOEpatents

    Miller, John L.; Hackel, Lloyd A.; Dane, Clifford B.; Zapata, Luis E.

    1994-01-01

    A regenerative amplifier design capable of operating at high energy per pulse, for instance, from 20-100 Joules, at moderate repetition rates, for instance from 5-20 Hertz is provided. The laser amplifier comprises a gain medium and source of pump energy coupled with the gain medium; a Pockels cell, which rotates an incident beam in response to application of a control signal; an optical relay system defining a first relay plane near the gain medium and a second relay plane near the rotator; and a plurality of reflectors configured to define an optical path through the gain medium, optical relay and Pockels cell, such that each transit of the optical path includes at least one pass through the gain medium and only one pass through the Pockels cell. An input coupler, and an output coupler are provided, implemented by a single polarizer. A control circuit coupled to the Pockels cell generates the control signal in timed relationship with the input pulse so that the input pulse is captured by the input coupler and proceeds through at least one transit of the optical path, and then the control signal is applied to cause rotation of the pulse to a polarization reflected by the polarizer, after which the captured pulse passes through the gain medium at least once more and is reflected out of the optical path by the polarizer before passing through the rotator again to provide an amplified pulse.

  16. High power regenerative laser amplifier

    DOEpatents

    Miller, J.L.; Hackel, L.A.; Dane, C.B.; Zapata, L.E.

    1994-02-08

    A regenerative amplifier design capable of operating at high energy per pulse, for instance, from 20-100 Joules, at moderate repetition rates, for instance from 5-20 Hertz is provided. The laser amplifier comprises a gain medium and source of pump energy coupled with the gain medium; a Pockels cell, which rotates an incident beam in response to application of a control signal; an optical relay system defining a first relay plane near the gain medium and a second relay plane near the rotator; and a plurality of reflectors configured to define an optical path through the gain medium, optical relay and Pockels cell, such that each transit of the optical path includes at least one pass through the gain medium and only one pass through the Pockels cell. An input coupler, and an output coupler are provided, implemented by a single polarizer. A control circuit coupled to the Pockels cell generates the control signal in timed relationship with the input pulse so that the input pulse is captured by the input coupler and proceeds through at least one transit of the optical path, and then the control signal is applied to cause rotation of the pulse to a polarization reflected by the polarizer, after which the captured pulse passes through the gain medium at least once more and is reflected out of the optical path by the polarizer before passing through the rotator again to provide an amplified pulse. 7 figures.

  17. Method and apparatus for communicating computer data from one point to another over a communications medium

    DOEpatents

    Arneson, Michael R [Chippewa Falls, WI; Bowman, Terrance L [Sumner, WA; Cornett, Frank N [Chippewa Falls, WI; DeRyckere, John F [Eau Claire, WI; Hillert, Brian T [Chippewa Falls, WI; Jenkins, Philip N [Eau Claire, WI; Ma, Nan [Chippewa Falls, WI; Placek, Joseph M [Chippewa Falls, WI; Ruesch, Rodney [Eau Claire, WI; Thorson, Gregory M [Altoona, WI

    2007-07-24

    The present invention is directed toward a communications channel comprising a link level protocol, a driver, a receiver, and a canceller/equalizer. The link level protocol provides logic for DC-free signal encoding and recovery as well as supporting many features including CRC error detection and message resend to accommodate infrequent bit errors across the medium. The canceller/equalizer provides equalization for destabilized data signals and also provides simultaneous bi-directional data transfer. The receiver provides bit deskewing by removing synchronization error, or skewing, between data signals. The driver provides impedance controlling by monitoring the characteristics of the communications medium, like voltage or temperature, and providing a matching output impedance in the signal driver so that fewer distortions occur while the data travels across the communications medium.

  18. Parametric instabilities and their control in multidimensional nonuniform gain media

    NASA Astrophysics Data System (ADS)

    Charbonneau-Lefort, Mathieu; Afeyan, Bedros; Fejer, Martin

    2007-11-01

    In order to control parametric instabilities in large scale long pulse laser produced plasmas, optical mixing techniques seem most promising [1]. We examine ways of controlling the growth of some modes while creating other unstable ones in nonuniform gain media, including the effects of transverse localization of the pump wave. We show that multidimensional effects are essential to understand laser-gain medium interactions [2] and that one dimensional models such as the celebrated Rosenbluth result [3] can be misleading [4]. These findings are verified in experiments carried out in a chirped quasi-phase-matched gratings in optical parametric amplifiers where thousands of shots can be taken and statistically significant and stable results obtained. [1] B. Afeyan, et al., IFSA Proceedings, 2003. [2] M. M. Sushchik and G. I. Freidman, Radiofizika 13, 1354 (1970). [3] M. N. Rosenbluth, Phys. Rev. Lett. 29, 565 (1972). [4] M. Charbonneau-Lefort, PhD thesis, Stanford University, 2007.

  19. Polyacrylamide medium for the electrophoretic separation of biomolecules

    DOEpatents

    Madabhushi, Ramakrishna S.; Gammon, Stuart A.

    2003-11-11

    A polyacryalmide medium for the electrophoretic separation of biomolecules. The polyacryalmide medium comprises high molecular weight polyacrylamides (PAAm) having a viscosity average molecular weight (M.sub.v) of about 675-725 kDa were synthesized by conventional red-ox polymerization technique. Using this separation medium, capillary electrophoresis of BigDye DNA sequencing standard was performed. A single base resolution of .about.725 bases was achieved in .about.60 minute in a non-covalently coated capillary of 50 .mu.m i.d., 40 cm effective length, and a filed of 160 V/cm at 40.degree. C. The resolution achieved with this formulation to separate DNA under identical conditions is much superior (725 bases vs. 625 bases) and faster (60 min. vs. 75 min.) to the commercially available PAAm, such as supplied by Amersham. The formulation method employed here to synthesize PAAm is straight-forward, simple and does not require cumbersome methods such as emulsion polymerizaiton in order to achieve very high molecular weights. Also, the formulation here does not require separation of PAAm from the reaction mixture prior to reconstituting the polymer to a final concentration. Furthermore, the formulation here is prepared from a single average mol. wt. PAAm as opposed to the mixture of two different average mo. wt. PAAm previously required to achieve high resolution.

  20. Oral Lactobacillus Counts Predict Weight Gain Susceptibility: A 6-Year Follow-Up Study

    PubMed Central

    Rosing, Johanne Aviaja; Walker, Karen Christina; Jensen, Benjamin A.H.; Heitmann, Berit L.

    2017-01-01

    Background Recent studies have shown an association between weight change and the makeup of the intestinal microbiota in humans. Specifically, Lactobacillus, a part of the entire gastrointestinal tract's microbiota, has been shown to contribute to weight regulation. Aim We examined the association between the level of oral Lactobacillus and the subsequent 6-year weight change in a healthy population of 322 Danish adults aged 35–65 years at baseline. Design Prospective observational study. Results In unadjusted analysis the level of oral Lactobacillus was inversely associated with subsequent 6-year change in BMI. A statistically significant interaction between the baseline level of oral Lactobacillus and the consumption of complex carbohydrates was found, e.g. high oral Lactobacillus count predicted weight loss for those with a low intake of complex carbohydrates, while a medium intake of complex carbohydrates predicted diminished weight gain. A closer examination of these relations showed that BMI change and Lactobacillus level was unrelated for those with high complex carbohydrate consumption. Conclusion A high level of oral Lactobacillus seems related to weight loss among those with medium and low intakes of complex carbohydrates. Absence, or a low level of oral Lactobacillus, may potentially be a novel marker to identify those at increased risk of weight gain. PMID:29020671

  1. Oral Lactobacillus Counts Predict Weight Gain Susceptibility: A 6-Year Follow-Up Study.

    PubMed

    Rosing, Johanne Aviaja; Walker, Karen Christina; Jensen, Benjamin A H; Heitmann, Berit L

    2017-01-01

    Recent studies have shown an association between weight change and the makeup of the intestinal microbiota in humans. Specifically, Lactobacillus, a part of the entire gastrointestinal tract's microbiota, has been shown to contribute to weight regulation. We examined the association between the level of oral Lactobacillus and the subsequent 6-year weight change in a healthy population of 322 Danish adults aged 35-65 years at baseline. Prospective observational study. In unadjusted analysis the level of oral Lactobacillus was inversely associated with subsequent 6-year change in BMI. A statistically significant interaction between the baseline level of oral Lactobacillus and the consumption of complex carbohydrates was found, e.g. high oral Lactobacillus count predicted weight loss for those with a low intake of complex carbohydrates, while a medium intake of complex carbohydrates predicted diminished weight gain. A closer examination of these relations showed that BMI change and Lactobacillus level was unrelated for those with high complex carbohydrate consumption. A high level of oral Lactobacillus seems related to weight loss among those with medium and low intakes of complex carbohydrates. Absence, or a low level of oral Lactobacillus, may potentially be a novel marker to identify those at increased risk of weight gain. © 2017 The Author(s) Published by S. Karger GmbH, Freiburg.

  2. Changing the Spatial Scope of Attention Alters Patterns of Neural Gain in Human Cortex

    PubMed Central

    Garcia, Javier O.; Rungratsameetaweemana, Nuttida; Sprague, Thomas C.

    2014-01-01

    Over the last several decades, spatial attention has been shown to influence the activity of neurons in visual cortex in various ways. These conflicting observations have inspired competing models to account for the influence of attention on perception and behavior. Here, we used electroencephalography (EEG) to assess steady-state visual evoked potentials (SSVEP) in human subjects and showed that highly focused spatial attention primarily enhanced neural responses to high-contrast stimuli (response gain), whereas distributed attention primarily enhanced responses to medium-contrast stimuli (contrast gain). Together, these data suggest that different patterns of neural modulation do not reflect fundamentally different neural mechanisms, but instead reflect changes in the spatial extent of attention. PMID:24381272

  3. Somatic embryogenesis of carrot in hormone-free medium: external pH control over morphogenesis

    NASA Technical Reports Server (NTRS)

    Smith, D. L.; Krikorian, A. D.

    1990-01-01

    Cultures of preglobular stage proembryos (PGSPs) were initiated from mechanically wounded mature zygotic embryos of carrot, Daucus carota, on a hormone-free, semisolid medium. These PGSPs have been maintained and multiplied for extended periods without their progression into later embryo stages on the same hormone-free medium containing 1 mM NH4+ as the sole nitrogen source. Sustained maintenance of cultures comprised exclusively of PGSPs was dependent on medium pH throughout the culture period. Best growth and multiplication of PGSP cultures occurred when the pH of unbuffered, hormone-free medium fell from 4.5 to 4 over a 2-week period or when buffered medium was titrated to pH 4. If the hormone-free medium was buffered to sustain a pH at or above 4.5, PGSPs developed into later embryo stages. Maintenance with continuous multiplication of PGSPs occurred equally well on medium containing NH4+ or NH4+ and NO3-, but growth was poor with NO3- alone. Additional observations on the effects of medium components such as various nitrogen sources and levels, sucrose concentration, semisolid supports, type of buffer, borate concentration, activated charcoal, and initial pH that permit optimum maintenance of the PGSPs or foster their continued developmental progression into mature embryos and plantlets are reported. The influence of the pH of the hormone-free medium as a determinant in maintaining cultures as PGSPs or allowing their continued embryonic development are unequivocally demonstrated by gross morphology, scanning electron microscopy, and histological preparations.

  4. College Freshmen Students' Perspectives on Weight Gain Prevention in the Digital Age: Web-Based Survey.

    PubMed

    Monroe, Courtney M; Turner-McGrievy, Gabrielle; Larsen, Chelsea A; Magradey, Karen; Brandt, Heather M; Wilcox, Sara; Sundstrom, Beth; West, Delia Smith

    2017-10-12

    College freshmen are highly vulnerable to experiencing weight gain, and this phenomenon is associated with an increased risk of chronic diseases and mortality in older adulthood. Technology offers an attractive and scalable way to deliver behavioral weight gain prevention interventions for this population. Weight gain prevention programs that harness the appeal and widespread reach of Web-based technologies (electronic health or eHealth) are increasingly being evaluated in college students. Yet, few of these interventions are informed by college students' perspectives on weight gain prevention and related lifestyle behaviors. The objective of this study was to assess college freshmen students' concern about weight gain and associated topics, as well as their interest in and delivery medium preferences for eHealth programs focused on these topics. Web-based surveys that addressed college freshmen students' (convenience sample of N=50) perspectives on weight gain prevention were administered at the beginning and end of the fall 2015 semester as part of a longitudinal investigation of health-related issues and experiences in first semester college freshmen. Data on weight gain prevention-related concerns and corresponding interest in eHealth programs targeting topics of potential concern, as well as preferred program delivery medium and current technology use were gathered and analyzed using descriptive statistics. A considerable proportion of the freshmen sample expressed concern about weight gain (74%, 37/50) and both traditional (healthy diet: 86%, 43/50; physical activity: 64%, 32/50) and less frequently addressed (stress: 82%, 41/50; sleep: 74%, 37/50; anxiety and depression: 60%, 30/50) associated topics within the context of behavioral weight gain prevention. The proportion of students who reported interest in eHealth promotion programs targeting these topics was also generally high (ranging from 52% [26/50] for stress management to 70% [35/50] for eating a

  5. "The Rolling Store" An economical and environmental approach to the prevention of weight gain in African American women.

    USDA-ARS?s Scientific Manuscript database

    The objective was to test the feasibility of the "Rolling Store," an innovative food delivery medium to provide healthy food choices (fruits and vegetables) to prevent weight gain in African American women. A randomized trial design was used in the study. Eligible participants from the community wer...

  6. Calcium-Iron Oxide as Energy Storage Medium in Rechargeable Oxide Batteries

    DOE PAGES

    Berger, Cornelius M.; Mahmoud, Abdelfattah; Hermann, Raphaël P.; ...

    2016-08-08

    Rechargeable oxide batteries (ROB) comprise a regenerative solid oxide cell (rSOC) and a storage medium for oxygen ions. A sealed ROB avoids pumping loss, heat loss, and gas purity expenses in comparison with conventional rSOC. However, the iron oxide base storage medium degrades during charging–discharging cycles. In comparison, CaFe 3O 5 has improved cyclability and a high reversible oxygen storage capacity of 22.3 mol%. In this paper, we analyzed the redox mechanism of this compound. After a solid-state synthesis of CaFe 3O 5, we verified the phase composition and studied the redox reaction by means of X-ray diffraction, Mössbauer spectrometry,more » and scanning electron microscopy. Finally, results show a great potential to operate the battery with this storage material during multiple charging–discharging cycles.« less

  7. Computer program for thin-wire structures in a homogeneous conducting medium

    NASA Technical Reports Server (NTRS)

    Richmond, J. H.

    1974-01-01

    A computer program is presented for thin-wire antennas and scatters in a homogeneous conducting medium. The anaylsis is performed in the real or complex frequency domain. The program handles insulated and bare wires with finite conductivity and lumped loads. The output data includes the current distribution, impedance, radiation efficiency, gain, absorption cross section, scattering cross section, echo area and the polarization scattering matrix. The program uses sinusoidal bases and Galerkin's method.

  8. Synthetic thermoelectric materials comprising phononic crystals

    DOEpatents

    El-Kady, Ihab F; Olsson, Roy H; Hopkins, Patrick; Reinke, Charles; Kim, Bongsang

    2013-08-13

    Synthetic thermoelectric materials comprising phononic crystals can simultaneously have a large Seebeck coefficient, high electrical conductivity, and low thermal conductivity. Such synthetic thermoelectric materials can enable improved thermoelectric devices, such as thermoelectric generators and coolers, with improved performance. Such synthetic thermoelectric materials and devices can be fabricated using techniques that are compatible with standard microelectronics.

  9. Electric line source illumination of a chiral cylinder placed in another chiral background medium

    NASA Astrophysics Data System (ADS)

    Aslam, M.; Saleem, A.; Awan, Z. A.

    2018-05-01

    An electric line source illumination of a chiral cylinder embedded in a chiral background medium is considered. The field expressions inside and outside of a chiral cylinder have been derived using the wave field decomposition approach. The effects of various chiral cylinders, chiral background media and source locations upon the scattering gain pattern have been investigated. It is observed that the chiral background reduces the backward scattering gain as compared to the free space background for a dielectric cylinder. It is also studied that by moving a line source away from a cylinder reduces the backward scattering gain for a chiral cylinder placed in a chiral background under some specific conditions. A unique phenomenon of reduced scattering gain has been observed at a specific observation angle for a chiral cylinder placed in a chiral background having an electric line source location of unity free space wavelength. An isotropic scattering gain pattern is observed for a chiral nihility background provided that if cylinder is chiral or chiral nihility type. It is also observed that this isotropic behaviour is independent of background and cylinder chirality.

  10. Simplified Modeling of Steady-State and Transient Brillouin Gain in Magnetoactive Non-Centrosymmetric Semiconductors

    NASA Astrophysics Data System (ADS)

    Singh, M.; Aghamkar, P.; Sen, P. K.

    With the aid of a hydrodynamic model of semiconductor-plasmas, a detailed analytical investigation is made to study both the steady-state and the transient Brillouin gain in magnetized non-centrosymmetric III-V semiconductors arising from the nonlinear interaction of an intense pump beam with the internally-generated acoustic wave, due to piezoelectric and electrostrictive properties of the crystal. Using the fact that the origin of coherent Brillouin scattering (CBS) lies in the third-order (Brillouin) susceptibility of the medium, we obtained an expression of the gain coefficient of backward Stokes mode in steady-state and transient regimes and studied the dependence of piezoelectricity, magnetic field and pump pulse duration on its growth rate. The threshold-pump intensity and optimum pulse duration for the onset of transient CBS are estimated. The piezoelectricity and externally-applied magnetic field substantially enhances the transient CBS gain coefficient in III-V semiconductors which can be of great use in the compression of scattered pulses.

  11. Do we need gadolinium-based contrast medium for brain magnetic resonance imaging in children?

    PubMed

    Dünger, Dennis; Krause, Matthias; Gräfe, Daniel; Merkenschlager, Andreas; Roth, Christian; Sorge, Ina

    2018-06-01

    Brain imaging is the most common examination in pediatric magnetic resonance imaging (MRI), often combined with the use of a gadolinium-based contrast medium. The application of gadolinium-based contrast medium poses some risk. There is limited evidence of the benefits of contrast medium in pediatric brain imaging. To assess the diagnostic gain of contrast-enhanced sequences in brain MRI when the unenhanced sequences are normal. We retrospectively assessed 6,683 brain MR examinations using contrast medium in children younger than 16 years in the pediatric radiology department of the University Hospital Leipzig to determine whether contrast-enhanced sequences delivered additional, clinically relevant information to pre-contrast sequences. All examinations were executed using a 1.5-T or a 3-T system. In 8 of 3,003 (95% confidence interval 0.12-0.52%) unenhanced normal brain examinations, a relevant additional finding was detected when contrast medium was administered. Contrast enhancement led to a change in diagnosis in only one of these cases. Children with a normal pre-contrast brain MRI rarely benefit from contrast medium application. Comparing these results to the risks and disadvantages of a routine gadolinium application, there is substantiated numerical evidence for avoiding routine administration of gadolinium in a pre-contrast normal MRI examination.

  12. Violet-to-Blue Gain and Lasing from Colloidal CdS Nanoplatelets: Low-Threshold Stimulated Emission Despite Low Photoluminescence Quantum Yield

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Diroll, Benjamin T.; Talapin, Dmitri V.; Schaller, Richard D.

    Amplified spontaneous emission (ASE) and lasing from solution-processed materials are demonstrated in the challenging violet-to-blue (430–490 nm) spectral region for colloidal nanoplatelets of CdS and newly synthesized core/shell CdS/ZnS nanoplatelets. Despite modest band-edge photoluminescence quantum yields of 2% or less for single excitons, which we show results from hole trapping, the samples exhibit low ASE thresholds. Furthermore, four-monolayer CdS samples show ASE at shorter wavelengths than any reported film of colloidal quantum-confined material. This work underlines that low quantum yields for single excitons do not necessarily lead to a poor gain medium. The low ASE thresholds originate from negligible dispersionmore » in thickness, large absorption cross sections of 2.8 × 10–14 cm–2, and rather slow (150 to 300 ps) biexciton recombination. We show that under higher-fluence excitation, ASE can kinetically outcompete hole trapping. Using nanoplatelets as the gain medium, lasing is observed in a linear optical cavity. This work confirms the fundamental advantages of colloidal quantum well structures as gain media, even in the absence of high photoluminescence efficiency.« less

  13. Structural analysis and taste evaluation of γ-glutamyl peptides comprising sulfur-containing amino acids.

    PubMed

    Amino, Yusuke; Wakabayashi, Hidehiko; Akashi, Satoko; Ishiwatari, Yutaka

    2018-03-01

    The structures, flavor-modifying effects, and CaSR activities of γ-glutamyl peptides comprising sulfur-containing amino acids were investigated. The chemical structures, including the linkage mode of the N-terminal glutamic acid, of γ-L-glutamyl-S-(2-propenyl)-L-cysteine (γ-L-glutamyl-S-allyl-L-cysteine) and its sulfoxide isolated from garlic were established by comparing their NMR spectra with those of authentic peptides prepared using chemical methods. Mass spectrometric analysis also enabled determination of the linkage modes in the glutamyl dipeptides by their characteristic fragmentation. In sensory evaluation, these peptides exhibited flavor-modifying effects (continuity) in umami solutions less pronounced but similar to that of glutathione. Furthermore, the peptides exhibited intrinsic flavor due to the sulfur-containing structure, which may be partially responsible for their flavor-modifying effects. In CaSR assays, γ-L-glutamyl-S-methyl-L-cysteinylglycine was most active, which indicates that the presence of a medium-sized aliphatic substituent at the second amino acid residue in γ-glutamyl peptides enhances CaSR activity.

  14. Nonlocal modification and quantum optical generalization of effective-medium theory for metamaterials

    NASA Astrophysics Data System (ADS)

    Wubs, Martijn; Yan, Wei; Amooghorban, Ehsan; Mortensen, N. Asger

    2013-09-01

    A well-known challenge for fabricating metamaterials is to make unit cells significantly smaller than the operating wavelength of light, so one can be sure that effective-medium theories apply. But do they apply? Here we show that nonlocal response in the metal constituents of the metamaterial leads to modified effective parameters for strongly subwavelength unit cells. For infinite hyperbolic metamaterials, nonlocal response gives a very large finite upper bound to the optical density of states that otherwise would diverge. Moreover, for finite hyperbolic metamaterials we show that nonlocal response affects their operation as superlenses, and interestingly that sometimes nonlocal theory predicts the better imaging. Finally, we discuss how to describe metamaterials effectively in quantum optics. Media with loss or gain have associated quantum noise, and the question is whether the effective index is enough to describe this quantum noise effectively. We show that this is true for passive metamaterials, but not for metamaterials where loss is compensated by linear gain. For such loss-compensated metamaterials we present a quantum optical effective medium theory with an effective noise photon distribution as an additional parameter. Interestingly, we find that at the operating frequency, metamaterials with the same effective index but with different amounts of loss compensation can be told apart in quantum optics.

  15. A 16.9 dBm InP DHBT W-band power amplifier with more than 20 dB gain

    NASA Astrophysics Data System (ADS)

    Hongfei, Yao; Yuxiong, Cao; Danyu, Wu; Xiaoxi, Ning; Yongbo, Su; Zhi, Jin

    2013-07-01

    A two-stage MMIC power amplifier has been realized by use of a 1-μm InP double heterojunction bipolar transistor (DHBT). The cascode structure, low-loss matching networks, and low-parasite cell units enhance the power gain. The optimum load impedance is determined from load-pull simulation. A coplanar waveguide transmission line is adopted for its ease of fabrication. The chip size is 1.5 × 1.7 mm2 with the emitter area of 16 × 1 μm × 15 μm in the output stage. Measurements show that small signal gain is more than 20 dB over 75.5-84.5 GHz and the saturated power is 16.9 dBm @ 79 GHz with gain of 15.2 dB. The high power gain makes it very suitable for medium power amplification.

  16. Downhole transmission system comprising a coaxial capacitor

    DOEpatents

    Hall, David R [Provo, UT; Pixton, David S [Lehi, UT; Johnson, Monte L [Orem, UT; Bartholomew, David B [Springville, UT; Hall, Jr., H. Tracy; Rawle, Michael [Springville, UT

    2011-05-24

    A transmission system in a downhole component comprises a plurality of data transmission elements. A coaxial cable having an inner conductor and an outer conductor is disposed within a passage in the downhole component such that at least one capacitor is disposed in the passage and having a first terminal coupled to the inner conductor and a second terminal coupled to the outer conductor. Preferably the transmission element comprises an electrically conducting coil. Preferably, within the passage a connector is adapted to electrically connect the inner conductor of the coaxial cable and the lead wire. The coaxial capacitor may be disposed between and in electrically communication with the connector and the passage. In another embodiment a connector is adapted to electrical connect a first and a second portion of the inner conductor of the coaxial cable and a coaxial capacitor is in electrical communication with the connector and the passage.

  17. Electrolyte membrane, methods of manufacture thereof and articles comprising the same

    DOEpatents

    Tamaki, Ryo; Rice, Steven Thomas; Yeager, Gary William

    2013-11-05

    Disclosed herein is a method of forming an electrolyte membrane comprising forming a mixture; the mixture comprising a polyhydroxy compound, an aromatic polyhalide compound and an alkali metal hydroxide; disposing the mixture on a porous substrate; reacting the mixture to form a crosslinked proton conductor; and sulfonating the proton conductor. Disclosed herein too is an article comprising a porous substrate; and a sulfonated crosslinked proton conductor disposed within pores of the porous substrate.

  18. The pattern of gestational weight gain is associated with changes in maternal body composition and neonatal size

    PubMed Central

    Widen, Elizabeth M.; Factor-Litvak, Pam R.; Gallagher, Dympna; Paxton, Anne; Pierson, Richard N.; Heymsfield, Steven B.; Lederman, Sally A.

    2015-01-01

    Objectives The pattern of gestational weight gain (GWG) reflects general nutrient availability to support growing fetal and maternal compartments and may contribute to later health; but how it relates to changes in maternal body composition is unknown. We evaluated how the pattern of gestational weight gain (GWG) related to changes in maternal body composition during pregnancy and infant size at birth. Methods A prospective, multi-ethnic cohort of 156 pregnant women and their infants was studied in New York City. Prenatal weights were used to estimate total and rate (kg/wk) of GWG by trimester. Linear regression models evaluated the association between trimester-specific GWG group (low, medium, high GWG) [total (low≤25%ile, high≥75%ile) or rate (defined by tertiles)] and infant weight, length and maternal body composition changes from 14–37 weeks, adjusting for covariates. Results Compared to the low gain group, medium/high rate of GWG in the second trimester and high rate of GWG in the third trimester was associated with larger gains in maternal fat mass (β range for fat Δ=2.86–5.29 kg, all p<0.01) For infant outcomes, high rate of GWG in the second trimester was associated with higher birth weight (β=356 g, p=0.001) and length (β=0.85 cm, p=0.002). First and third trimester GWG were not associated with neonatal size. Conclusions The trimester specific pattern and rate of GWG reflect changes in maternal body fat and body water, and are associated with neonatal size, which supports the importance of monitoring trimester-specific GWG. PMID:26179720

  19. Material gain engineering in GeSn/Ge quantum wells integrated with an Si platform

    NASA Astrophysics Data System (ADS)

    Mączko, H. S.; Kudrawiec, R.; Gladysiewicz, M.

    2016-09-01

    It is shown that compressively strained Ge1-xSnx/Ge quantum wells (QWs) grown on a Ge substrate with 0.1 ≤ x ≤ 0.2 and width of 8 nm ≤ d ≤ 14 nm are a very promising gain medium for lasers integrated with an Si platform. Such QWs are type-I QWs with a direct bandgap and positive transverse electric mode of material gain, i.e. the modal gain. The electronic band structure near the center of Brillouin zone has been calculated for various Ge1-xSnx/Ge QWs with use of the 8-band kp Hamiltonian. To calculate the material gain for these QWs, occupation of the L valley in Ge barriers has been taken into account. It is clearly shown that this occupation has a lot of influence on the material gain in the QWs with low Sn concentrations (Sn < 15%) and is less important for QWs with larger Sn concentration (Sn > 15%). However, for QWs with Sn > 20% the critical thickness of a GeSn layer deposited on a Ge substrate starts to play an important role. Reduction in the QW width shifts up the ground electron subband in the QW and increases occupation of the L valley in the barriers instead of the Γ valley in the QW region.

  20. Electrolyte membrane, methods of manufacture thereof and articles comprising the same

    DOEpatents

    Tamaki, Ryo [Santa Clarita, CA; Rice, Steven Thomas [Scotia, NY; Yeager, Gary William [Rexford, NY

    2012-06-12

    Disclosed herein is a method of forming an electrolyte membrane comprising forming a mixture; the mixture comprising a polyhydroxy compound, an aromatic polyhalide compound and an alkali metal hydroxide; disposing the mixture on a porous substrate; reacting the mixture to form a proton conductor; and crosslinking the proton conductor to form a cross-linked proton-conducting network. Disclosed herein too is an article comprising a porous substrate; and a crosslinked proton conductor disposed on the porous substrate.

  1. Optically pumped alkali laser and amplifier using helium-3 buffer gas

    DOEpatents

    Beach, Raymond J.; Page, Ralph; Soules, Thomas; Stappaerts, Eddy; Wu, Sheldon Shao Quan

    2010-09-28

    In one embodiment, a laser oscillator is provided comprising an optical cavity, the optical cavity including a gain medium including an alkali vapor and a buffer gas, the buffer gas including .sup.3He gas, wherein if .sup.4He gas is also present in the buffer gas, the ratio of the concentration of the .sup.3He gas to the .sup.4He gas is greater than 1.37.times.10.sup.-6. Additionally, an optical excitation source is provided. Furthermore, the laser oscillator is capable of outputting radiation at a first frequency. In another embodiment, an apparatus is provided comprising a gain medium including an alkali vapor and a buffer gas including .sup.3He gas, wherein if .sup.4He gas is also present in the buffer gas, the ratio of the concentration of the .sup.3He gas to the .sup.4He gas is greater than 1.37.times.10.sup.-6. Other embodiments are also disclosed.

  2. Electrode material comprising graphene-composite materials in a graphite network

    DOEpatents

    Kung, Harold H.; Lee, Jung K.

    2014-07-15

    A durable electrode material suitable for use in Li ion batteries is provided. The material is comprised of a continuous network of graphite regions integrated with, and in good electrical contact with a composite comprising graphene sheets and an electrically active material, such as silicon, wherein the electrically active material is dispersed between, and supported by, the graphene sheets.

  3. Electrode material comprising graphene-composite materials in a graphite network

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kung, Harold H.; Lee, Jung K.

    A durable electrode material suitable for use in Li ion batteries is provided. The material is comprised of a continuous network of graphite regions integrated with, and in good electrical contact with a composite comprising graphene sheets and an electrically active material, such as silicon, wherein the electrically active material is dispersed between, and supported by, the graphene sheets.

  4. Cells Comprising the Prostate Cancer Microenvironment Lack Recurrent Clonal Somatic Genomic Aberrations

    PubMed Central

    Bianchi-Frias, Daniella; Basom, Ryan; Delrow, Jeffrey J; Coleman, Ilsa M; Dakhova, Olga; Qu, Xiaoyu; Fang, Min; Franco, Omar E.; Ericson, Nolan G.; Bielas, Jason H.; Hayward, Simon W.; True, Lawrence; Morrissey, Colm; Brown, Lisha; Bhowmick, Neil A.; Rowley, David; Ittmann, Michael; Nelson, Peter S.

    2017-01-01

    Prostate cancer-associated stroma (CAS) plays an active role in malignant transformation, tumor progression, and metastasis. Molecular analyses of CAS have demonstrated significant changes in gene expression; however, conflicting evidence exists on whether genomic alterations in benign cells comprising the tumor microenvironment (TME) underlie gene expression changes and oncogenic phenotypes. This study evaluates the nuclear and mitochondrial DNA integrity of prostate carcinoma cells, CAS, matched benign epithelium and benign epithelium-associated stroma by whole genome copy number analyses, targeted sequencing of TP53, and fluorescence in situ hybridization. Comparative genomic hybridization (aCGH) of CAS revealed a copy-neutral diploid genome with only rare and small somatic copy number aberrations (SCNAs). In contrast, several expected recurrent SCNAs were evident in the adjacent prostate carcinoma cells, including gains at 3q, 7p, and 8q, and losses at 8p and 10q. No somatic TP53 mutations were observed in CAS. Mitochondrial DNA (mtDNA) extracted from carcinoma cells and stroma identified 23 somatic mtDNA mutations in neoplastic epithelial cells but only one mutation in stroma. Finally, genomic analyses identified no SCNAs, no loss of heterozygosity (LOH) or copy-neutral LOH in cultured cancer-associated fibroblasts (CAFs), which are known to promote prostate cancer progression in vivo. PMID:26753621

  5. Electrochemical Device Comprising Composite Bipolar Plate and Method of Using the Same

    NASA Technical Reports Server (NTRS)

    Mittelsteadt, Cortney K. (Inventor); Braff, William A. (Inventor)

    2013-01-01

    An electrochemical device and methods of using the same. In one embodiment, the electrochemical device may be used as a fuel cell and/or as an electrolyzer and includes a membrane electrode assembly (MEA), an anodic gas diffusion medium in contact with the anode of the MEA, a cathodic gas diffusion medium in contact with the cathode, a first bipolar plate in contact with the anodic gas diffusion medium, and a second bipolar plate in contact with the cathodic gas diffusion medium. Each of the bipolar plates includes an electrically-conductive, chemically-inert, non-porous, liquid-permeable, substantially gas-impermeable membrane in contact with its respective gas diffusion medium, as well as a fluid chamber and a non-porous an electrically-conductive plate.

  6. Electrochemical Device Comprising Composite Bipolar Plate and Method of Using the Same

    NASA Technical Reports Server (NTRS)

    Mittelsteadt, Cortney K. (Inventor); Braff, William A. (Inventor)

    2017-01-01

    An electrochemical device and methods of using the same. In one embodiment, the electrochemical device may be used as a fuel cell and/or as an electrolyzer and includes a membrane electrode assembly (MEA), an anodic gas diffusion medium in contact with the anode of the MEA, a cathodic gas diffusion medium in contact with the cathode, a first bipolar plate in contact with the anodic gas diffusion medium, and a second bipolar plate in contact with the cathodic gas diffusion medium. Each of the bipolar plates includes an electrically-conductive, chemically-inert, non-porous, liquid-permeable, substantially gas-impermeable membrane in contact with its respective gas diffusion medium, as well as a fluid chamber and a non-porous an electrically-conductive plate.

  7. Low-phonon-frequency chalcogenide crystalline hosts for rare earth lasers operating beyond three microns

    DOEpatents

    Payne, Stephen A.; Page, Ralph H.; Schaffers, Kathleen I.; Nostrand, Michael C.; Krupke, William F.; Schunemann, Peter G.

    2000-01-01

    The invention comprises a RE-doped MA.sub.2 X.sub.4 crystalline gain medium, where M includes a divalent ion such as Mg, Ca, Sr, Ba, Pb, Eu, or Yb; A is selected from trivalent ions including Al, Ga, and In; X is one of the chalcogenide ions S, Se, and Te; and RE represents the trivalent rare earth ions. The MA.sub.2 X.sub.4 gain medium can be employed in a laser oscillator or a laser amplifier. Possible pump sources include diode lasers, as well as other laser pump sources. The laser wavelengths generated are greater than 3 microns, as becomes possible because of the low phonon frequency of this host medium. The invention may be used to seed optical devices such as optical parametric oscillators and other lasers.

  8. Food cue reactivity and craving predict eating and weight gain: a meta-analytic review.

    PubMed

    Boswell, Rebecca G; Kober, Hedy

    2016-02-01

    According to learning-based models of behavior, food cue reactivity and craving are conditioned responses that lead to increased eating and subsequent weight gain. However, evidence supporting this relationship has been mixed. We conducted a quantitative meta-analysis to assess the predictive effects of food cue reactivity and craving on eating and weight-related outcomes. Across 69 reported statistics from 45 published reports representing 3,292 participants, we found an overall medium effect of food cue reactivity and craving on outcomes (r = 0.33, p < 0.001; approximately 11% of variance), suggesting that cue exposure and the experience of craving significantly influence and contribute to eating behavior and weight gain. Follow-up tests revealed a medium effect size for the effect of both tonic and cue-induced craving on eating behavior (r = 0.33). We did not find significant differences in effect sizes based on body mass index, age, or dietary restraint. However, we did find that visual food cues (e.g. pictures and videos) were associated with a similar effect size to real food exposure and a stronger effect size than olfactory cues. Overall, the present findings suggest that food cue reactivity, cue-induced craving and tonic craving systematically and prospectively predict food-related outcomes. These results have theoretical, methodological, public health and clinical implications. © 2015 World Obesity.

  9. Thermoacoustic refrigerators and engines comprising cascading stirling thermodynamic units

    DOEpatents

    Backhaus, Scott; Swift, Greg

    2013-06-25

    The present invention includes a thermoacoustic assembly and method for improved efficiency. The assembly has a first stage Stirling thermal unit comprising a main ambient heat exchanger, a regenerator and at least one additional heat exchanger. The first stage Stirling thermal unit is serially coupled to a first end of a quarter wavelength long coupling tube. A second stage Stirling thermal unit comprising a main ambient heat exchanger, a regenerator, and at least one additional heat exchanger, is serially coupled to a second end of the quarter wavelength long coupling tube.

  10. Biocatalytic material comprising multilayer enzyme coated fiber

    DOEpatents

    Kim, Jungbae [Richland, WA; Kwak, Ja Hun [Richland, WA; Grate, Jay W [West Richland, WA

    2009-11-03

    The present invention relates generally to high stability, high activity biocatalytic materials and processes for using the same. The materials comprise enzyme aggregate coatings having high biocatalytic activity and stability useful in heterogeneous environment. These new materials provide a new biocatalytic immobilized enzyme system with applications in bioconversion, bioremediation, biosensors, and biofuel cells.

  11. Medium-sized tandem repeats represent an abundant component of the Drosophila virilis genome.

    PubMed

    Abdurashitov, Murat A; Gonchar, Danila A; Chernukhin, Valery A; Tomilov, Victor N; Tomilova, Julia E; Schostak, Natalia G; Zatsepina, Olga G; Zelentsova, Elena S; Evgen'ev, Michael B; Degtyarev, Sergey K H

    2013-11-09

    Previously, we developed a simple method for carrying out a restriction enzyme analysis of eukaryotic DNA in silico, based on the known DNA sequences of the genomes. This method allows the user to calculate lengths of all DNA fragments that are formed after a whole genome is digested at the theoretical recognition sites of a given restriction enzyme. A comparison of the observed peaks in distribution diagrams with the results from DNA cleavage using several restriction enzymes performed in vitro have shown good correspondence between the theoretical and experimental data in several cases. Here, we applied this approach to the annotated genome of Drosophila virilis which is extremely rich in various repeats. Here we explored the combined approach to perform the restriction analysis of D. virilis DNA. This approach enabled to reveal three abundant medium-sized tandem repeats within the D. virilis genome. While the 225 bp repeats were revealed previously in intergenic non-transcribed spacers between ribosomal genes of D. virilis, two other families comprised of 154 bp and 172 bp repeats were not described. Tandem Repeats Finder search demonstrated that 154 bp and 172 bp units are organized in multiple clusters in the genome of D. virilis. Characteristically, only 154 bp repeats derived from Helitron transposon are transcribed. Using in silico digestion in combination with conventional restriction analysis and sequencing of repeated DNA fragments enabled us to isolate and characterize three highly abundant families of medium-sized repeats present in the D. virilis genome. These repeats comprise a significant portion of the genome and may have important roles in genome function and structural integrity. Therefore, we demonstrated an approach which makes possible to investigate in detail the gross arrangement and expression of medium-sized repeats basing on sequencing data even in the case of incompletely assembled and/or annotated genomes.

  12. Factors Influencing Information Communication Technology (ICT) Acceptance and Use in Small and Medium Enterprises (SMEs) in Kenya

    ERIC Educational Resources Information Center

    Nyandoro, Cephus K.

    2016-01-01

    Research demonstrates that there is a gap in focusing understanding factors of information communication technology (ICT) acceptance and use in small and medium enterprises (SMEs). ICT is gaining popularity because it is a force in the economic growth equation. SMEs adopt ICT to promote their business strategy, performance, and growth. This study…

  13. Impact of Raman scattering on pulse dynamics in a fiber laser with narrow gain bandwidth

    NASA Astrophysics Data System (ADS)

    Uthayakumar, T.; Alsaleh, M.; Igbonacho, J.; Tchomgo Felenou, E.; Tchofo Dinda, P.; Grelu, Ph; Porsezian, K.

    2018-06-01

    We examine theoretically the multi-pulse dynamics in a dispersion-managed fiber laser, in which the pulse’s spectral width is controlled by a pass-band filter. We show that in the domain of stable states with very narrow spectral width, i.e. which is one order of magnitude smaller than the bandwidth of the Raman gain of the intra-cavity fiber system, the Raman scattering (RS) significantly alters the multi-pulse dynamics. RS is found to have a greater impact in the immediate vicinity of some critical values of the pump power of the intra-cavity gain medium, where processes of pulse fragmentation occur. As a result, all the borders between the zones of stability of the multi-pulse states are altered, i.e. either shifted or suppressed.

  14. Calibrated Noise Measurements with Induced Receiver Gain Fluctuations

    NASA Technical Reports Server (NTRS)

    Racette, Paul; Walker, David; Gu, Dazhen; Rajola, Marco; Spevacek, Ashly

    2011-01-01

    The lack of well-developed techniques for modeling changing statistical moments in our observations has stymied the application of stochastic process theory in science and engineering. These limitations were encountered when modeling the performance of radiometer calibration architectures and algorithms in the presence of non stationary receiver fluctuations. Analyses of measured signals have traditionally been limited to a single measurement series. Whereas in a radiometer that samples a set of noise references, the data collection can be treated as an ensemble set of measurements of the receiver state. Noise Assisted Data Analysis is a growing field of study with significant potential for aiding the understanding and modeling of non stationary processes. Typically, NADA entails adding noise to a signal to produce an ensemble set on which statistical analysis is performed. Alternatively as in radiometric measurements, mixing a signal with calibrated noise provides, through the calibration process, the means to detect deviations from the stationary assumption and thereby a measurement tool to characterize the signal's non stationary properties. Data sets comprised of calibrated noise measurements have been limited to those collected with naturally occurring fluctuations in the radiometer receiver. To examine the application of NADA using calibrated noise, a Receiver Gain Modulation Circuit (RGMC) was designed and built to modulate the gain of a radiometer receiver using an external signal. In 2010, an RGMC was installed and operated at the National Institute of Standards and Techniques (NIST) using their Noise Figure Radiometer (NFRad) and national standard noise references. The data collected is the first known set of calibrated noise measurements from a receiver with an externally modulated gain. As an initial step, sinusoidal and step-function signals were used to modulate the receiver gain, to evaluate the circuit characteristics and to study the performance of

  15. Synthetic laser medium

    DOEpatents

    Stokowski, S.E.

    1987-10-20

    A laser medium is particularly useful in high average power solid state lasers. The laser medium includes a chromium dopant and preferably neodymium ions as codopant, and is primarily a gadolinium scandium gallium garnet, or an analog thereof. Divalent cations inhibit spiral morphology as large boules from which the laser medium is derived are grown, and a source of ions convertible between a trivalent state and a tetravalent state at a low ionization energy are in the laser medium to reduce an absorption coefficient at about one micron wavelength otherwise caused by the divalent cations. These divalent cations and convertible ions are dispersed in the laser medium. Preferred convertible ions are provided from titanium or cerium sources.

  16. Synthetic laser medium

    DOEpatents

    Stokowski, Stanley E.

    1989-01-01

    A laser medium is particularly useful in high average power solid state lasers. The laser medium includes a chormium dopant and preferably neodymium ions as codopant, and is primarily a gadolinium scandium gallium garnet, or an analog thereof. Divalent cations inhibit spiral morphology as large boules from which the laser medium is derived are grown, and a source of ions convertible between a trivalent state and a tetravalent state at a low ionization energy are in the laser medium to reduce an absorption coefficient at about one micron wavelength otherwise caused by the divalent cations. These divalent cations and convertible ions are dispersed in the laser medium. Preferred convertible ions are provided from titanium or cerium sources.

  17. Metal-polymer composites comprising nanostructures and applications thereof

    DOEpatents

    Wang, Hsing-Lin [Los Alamos, NM; Jeon, Sea Ho [Dracut, MA; Mack, Nathan H [Los Alamos, NM

    2011-08-02

    Metal-polymer composites, and methods of making and use thereof, said composites comprising a thermally-cured dense polyaniline substrate; an acid dopant; and, metal nanostructure deposits wherein the deposits have a morphology dependent upon the acid dopant.

  18. Metal-polymer composites comprising nanostructures and applications thereof

    DOEpatents

    Wang, Hsing-Lin [Los Alamos, NM; Jeon, Sea Ho [Dracut, MA; Mack, Nathan H [Los Alamos, NM

    2012-04-03

    Metal-polymer composites, and methods of making and use thereof, said composites comprising a thermally-cured dense polyaniline substrate; an acid dopant; and, metal nanostructure deposits wherein the deposits have a morphology dependent upon the acid dopant.

  19. Developmental gains in visuospatial memory predict gains in mathematics achievement.

    PubMed

    Li, Yaoran; Geary, David C

    2013-01-01

    Visuospatial competencies are related to performance in mathematical domains in adulthood, but are not consistently related to mathematics achievement in children. We confirmed the latter for first graders and demonstrated that children who show above average first-to-fifth grade gains in visuospatial memory have an advantage over other children in mathematics. The study involved the assessment of the mathematics and reading achievement of 177 children in kindergarten to fifth grade, inclusive, and their working memory capacity and processing speed in first and fifth grade. Intelligence was assessed in first grade and their second to fourth grade teachers reported on their in-class attentive behavior. Developmental gains in visuospatial memory span (d = 2.4) were larger than gains in the capacity of the central executive (d = 1.6) that in turn were larger than gains in phonological memory span (d = 1.1). First to fifth grade gains in visuospatial memory and in speed of numeral processing predicted end of fifth grade mathematics achievement, as did first grade central executive scores, intelligence, and in-class attentive behavior. The results suggest there are important individual differences in the rate of growth of visuospatial memory during childhood and that these differences become increasingly important for mathematics learning.

  20. Developmental Gains in Visuospatial Memory Predict Gains in Mathematics Achievement

    PubMed Central

    Li, Yaoran; Geary, David C.

    2013-01-01

    Visuospatial competencies are related to performance in mathematical domains in adulthood, but are not consistently related to mathematics achievement in children. We confirmed the latter for first graders and demonstrated that children who show above average first-to-fifth grade gains in visuospatial memory have an advantage over other children in mathematics. The study involved the assessment of the mathematics and reading achievement of 177 children in kindergarten to fifth grade, inclusive, and their working memory capacity and processing speed in first and fifth grade. Intelligence was assessed in first grade and their second to fourth grade teachers reported on their in-class attentive behavior. Developmental gains in visuospatial memory span (d = 2.4) were larger than gains in the capacity of the central executive (d = 1.6) that in turn were larger than gains in phonological memory span (d = 1.1). First to fifth grade gains in visuospatial memory and in speed of numeral processing predicted end of fifth grade mathematics achievement, as did first grade central executive scores, intelligence, and in-class attentive behavior. The results suggest there are important individual differences in the rate of growth of visuospatial memory during childhood and that these differences become increasingly important for mathematics learning. PMID:23936154

  1. Substrate comprising a nanometer-scale projection array

    DOEpatents

    Cui, Yi; Zhu, Jia; Hsu, Ching-Mei; Connor, Stephen T; Yu, Zongfu; Fan, Shanhui; Burkhard, George

    2012-11-27

    A method for forming a substrate comprising nanometer-scale pillars or cones that project from the surface of the substrate is disclosed. The method enables control over physical characteristics of the projections including diameter, sidewall angle, and tip shape. The method further enables control over the arrangement of the projections including characteristics such as center-to-center spacing and separation distance.

  2. Non-cementitious compositions comprising vaterite and methods thereof

    DOEpatents

    Devenney, Martin; Fernandez, Miguel; Morgan, Samuel O.

    2015-09-15

    Non-cementitious compositions and products are provided. The compositions of the invention include a carbonate additive comprising vaterite such as reactive vaterite. Additional aspects of the invention include methods of making and using the non-cementitious compositions and products.

  3. 'That proves my point': How mediums reconstrue disconfirmation in medium-sitter interactions.

    PubMed

    Enoksen, Anette Einan; Dickerson, Paul

    2018-04-01

    Previous research has examined how the talk of mediums attends to the epistemological status of their readings. Such work has identified that mediums frequently use question-framed propositions that are typically confirmed by the sitter, thereby conferring epistemological status on the medium. This study seeks to investigate what happens when the sitter disconfirms the propositions of the medium. The study focuses on the ways in which such disconfirmation can be responded to such that it is reconstrued as evidence of the psychic nature of the medium's reading. Televised demonstrations of psychic readings involving British and US mediums and their sitters are analysed. The results suggest that mediums rework disconfirmation as proof in several ways: first, by emphasizing the different access that sitter and medium have to knowledge (e.g., about the future); second, as evidence that the medium has access to the actual voice of the deceased (and may therefore mishear what the deceased has said to them); and third, as revealing an important truth that has hitherto been concealed from the sitter. The implications of these findings are considered for cases where speakers bring different and potentially competing, epistemological resources to an interaction. © 2018 The British Psychological Society.

  4. Quantum optical effective-medium theory and transformation quantum optics for metamaterials

    NASA Astrophysics Data System (ADS)

    Wubs, Martijn; Amooghorban, Ehsan; Zhang, Jingjing; Mortensen, N. Asger

    2016-09-01

    While typically designed to manipulate classical light, metamaterials have many potential applications for quantum optics as well. We argue why a quantum optical effective-medium theory is needed. We present such a theory for layered metamaterials that is valid for light propagation in all spatial directions, thereby generalizing earlier work for one-dimensional propagation. In contrast to classical effective-medium theory there is an additional effective parameter that describes quantum noise. Our results for metamaterials are based on a rather general Lagrangian theory for the quantum electrodynamics of media with both loss and gain. In the second part of this paper, we present a new application of transformation optics whereby local spontaneous-emission rates of quantum emitters can be designed. This follows from an analysis how electromagnetic Green functions trans- form under coordinate transformations. Spontaneous-emission rates can be either enhanced or suppressed using invisibility cloaks or gradient index lenses. Furthermore, the anisotropic material profile of the cloak enables the directional control of spontaneous emission.

  5. External locus of control contributes to racial disparities in memory and reasoning training gains in ACTIVE

    PubMed Central

    Zahodne, Laura B.; Meyer, Oanh L.; Choi, Eunhee; Thomas, Michael L.; Willis, Sherry L.; Marsiske, Michael; Gross, Alden L.; Rebok, George W.; Parisi, Jeanine M.

    2015-01-01

    Racial disparities in cognitive outcomes may be partly explained by differences in locus of control. African Americans report more external locus of control than non-Hispanic Whites, and external locus of control is associated with poorer health and cognition. The aims of this study were to compare cognitive training gains between African American and non-Hispanic White participants in the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) study and determine whether racial differences in training gains are mediated by locus of control. The sample comprised 2,062 (26% African American) adults aged 65 and older who participated in memory, reasoning, or speed training. Latent growth curve models evaluated predictors of 10-year cognitive trajectories separately by training group. Multiple group modeling examined associations between training gains and locus of control across racial groups. Compared to non-Hispanic Whites, African Americans evidenced less improvement in memory and reasoning performance after training. These effects were partially mediated by locus of control, controlling for age, sex, education, health, depression, testing site, and initial cognitive ability. African Americans reported more external locus of control, which was associated with smaller training gains. External locus of control also had a stronger negative association with reasoning training gain for African Americans than for Whites. No racial difference in training gain was identified for speed training. Future intervention research with African Americans should test whether explicitly targeting external locus of control leads to greater cognitive improvement following cognitive training. PMID:26237116

  6. Enhanced Bio-Ethanol Production from Industrial Potato Waste by Statistical Medium Optimization

    PubMed Central

    Izmirlioglu, Gulten; Demirci, Ali

    2015-01-01

    Industrial wastes are of great interest as a substrate in production of value-added products to reduce cost, while managing the waste economically and environmentally. Bio-ethanol production from industrial wastes has gained attention because of its abundance, availability, and rich carbon and nitrogen content. In this study, industrial potato waste was used as a carbon source and a medium was optimized for ethanol production by using statistical designs. The effect of various medium components on ethanol production was evaluated. Yeast extract, malt extract, and MgSO4·7H2O showed significantly positive effects, whereas KH2PO4 and CaCl2·2H2O had a significantly negative effect (p-value < 0.05). Using response surface methodology, a medium consisting of 40.4 g/L (dry basis) industrial waste potato, 50 g/L malt extract, and 4.84 g/L MgSO4·7H2O was found optimal and yielded 24.6 g/L ethanol at 30 °C, 150 rpm, and 48 h of fermentation. In conclusion, this study demonstrated that industrial potato waste can be used effectively to enhance bioethanol production. PMID:26501261

  7. Enhanced Bio-Ethanol Production from Industrial Potato Waste by Statistical Medium Optimization.

    PubMed

    Izmirlioglu, Gulten; Demirci, Ali

    2015-10-15

    Industrial wastes are of great interest as a substrate in production of value-added products to reduce cost, while managing the waste economically and environmentally. Bio-ethanol production from industrial wastes has gained attention because of its abundance, availability, and rich carbon and nitrogen content. In this study, industrial potato waste was used as a carbon source and a medium was optimized for ethanol production by using statistical designs. The effect of various medium components on ethanol production was evaluated. Yeast extract, malt extract, and MgSO₄·7H₂O showed significantly positive effects, whereas KH₂PO₄ and CaCl₂·2H₂O had a significantly negative effect (p-value<0.05). Using response surface methodology, a medium consisting of 40.4 g/L (dry basis) industrial waste potato, 50 g/L malt extract, and 4.84 g/L MgSO₄·7H₂O was found optimal and yielded 24.6 g/L ethanol at 30 °C, 150 rpm, and 48 h of fermentation. In conclusion, this study demonstrated that industrial potato waste can be used effectively to enhance bioethanol production.

  8. The Pattern of Gestational Weight Gain is Associated with Changes in Maternal Body Composition and Neonatal Size.

    PubMed

    Widen, Elizabeth M; Factor-Litvak, Pam R; Gallagher, Dympna; Paxton, Anne; Pierson, Richard N; Heymsfield, Steven B; Lederman, Sally A

    2015-10-01

    The pattern of gestational weight gain (GWG) reflects general nutrient availability to support growing fetal and maternal compartments and may contribute to later health, but how it relates to changes in maternal body composition is unknown. We evaluated how the pattern of GWG related to changes in maternal body composition during pregnancy and infant size at birth. A prospective, multi-ethnic cohort of 156 pregnant women and their infants was studied in New York City. Prenatal weights were used to estimate total and rate (kg/week) of GWG by trimester. Linear regression models evaluated the association between trimester-specific GWG group (low, medium, high GWG) [total (low ≤25, high ≥75 percentile) or rate (defined by tertiles)] and infant weight, length and maternal body composition changes from 14 to 37 weeks, adjusting for covariates. Compared to the low gain group, medium/high rate of GWG in the second trimester and high rate of GWG in the third trimester were associated with larger gains in maternal fat mass (β range for fat Δ = 2.86-5.29 kg, all p < 0.01). For infant outcomes, high rate of GWG in the second trimester was associated with higher birth weight (β = 356 g, p = 0.001) and length (β = 0.85 cm, p = 0.002). First and third trimester GWG were not associated with neonatal size. The trimester specific pattern and rate of GWG reflect changes in maternal body fat and body water, and are associated with neonatal size, which supports the importance of monitoring trimester-specific GWG.

  9. An amorphous silicon photodiode with 2 THz gain-bandwidth product based on cycling excitation process

    NASA Astrophysics Data System (ADS)

    Yan, Lujiang; Yu, Yugang; Zhang, Alex Ce; Hall, David; Niaz, Iftikhar Ahmad; Raihan Miah, Mohammad Abu; Liu, Yu-Hsin; Lo, Yu-Hwa

    2017-09-01

    Since impact ionization was observed in semiconductors over half a century ago, avalanche photodiodes (APDs) using impact ionization in a fashion of chain reaction have been the most sensitive semiconductor photodetectors. However, APDs have relatively high excess noise, a limited gain-bandwidth product, and high operation voltage, presenting a need for alternative signal amplification mechanisms of superior properties. As an amplification mechanism, the cycling excitation process (CEP) was recently reported in a silicon p-n junction with subtle control and balance of the impurity levels and profiles. Realizing that CEP effect depends on Auger excitation involving localized states, we made the counter intuitive hypothesis that disordered materials, such as amorphous silicon, with their abundant localized states, can produce strong CEP effects with high gain and speed at low noise, despite their extremely low mobility and large number of defects. Here, we demonstrate an amorphous silicon low noise photodiode with gain-bandwidth product of over 2 THz, based on a very simple structure. This work will impact a wide range of applications involving optical detection because amorphous silicon, as the primary gain medium, is a low-cost, easy-to-process material that can be formed on many kinds of rigid or flexible substrates.

  10. Gain weighted eigenspace assignment

    NASA Technical Reports Server (NTRS)

    Davidson, John B.; Andrisani, Dominick, II

    1994-01-01

    This report presents the development of the gain weighted eigenspace assignment methodology. This provides a designer with a systematic methodology for trading off eigenvector placement versus gain magnitudes, while still maintaining desired closed-loop eigenvalue locations. This is accomplished by forming a cost function composed of a scalar measure of error between desired and achievable eigenvectors and a scalar measure of gain magnitude, determining analytical expressions for the gradients, and solving for the optimal solution by numerical iteration. For this development the scalar measure of gain magnitude is chosen to be a weighted sum of the squares of all the individual elements of the feedback gain matrix. An example is presented to demonstrate the method. In this example, solutions yielding achievable eigenvectors close to the desired eigenvectors are obtained with significant reductions in gain magnitude compared to a solution obtained using a previously developed eigenspace (eigenstructure) assignment method.

  11. Sequence specific motor performance gains after memory consolidation in children and adolescents.

    PubMed

    Dorfberger, Shoshi; Adi-Japha, Esther; Karni, Avi

    2012-01-01

    Memory consolidation for a trained sequence of finger opposition movements, in 9- and 12-year-old children, was recently found to be significantly less susceptible to interference by a subsequent training experience, compared to that of 17-year-olds. It was suggested that, in children, the experience of training on any sequence of finger movements may affect the performance of the sequence elements, component movements, rather than the sequence as a unit; the latter has been implicated in the learning of the task by adults. This hypothesis implied a possible childhood advantage in the ability to transfer the gains from a trained to the reversed, untrained, sequence of movements. Here we report the results of transfer tests undertaken to test this proposal in 9-, 12-, and 17-year-olds after training in the finger-to-thumb opposition sequence (FOS) learning task. Our results show that the performance gains in the trained sequence partially transferred from the left, trained hand, to the untrained hand at 48-hours after a single training session in the three age-groups tested. However, there was very little transfer of the gains from the trained to the untrained, reversed, sequence performed by either hand. The results indicate sequence specific post-training gains in FOS performance, as opposed to a general improvement in performance of the individual, component, movements that comprised both the trained and untrained sequences. These results do not support the proposal that the reduced susceptibility to interference, in children before adolescence, reflects a difference in movement syntax representation after training.

  12. A selective medium for recovery and enumeration of endolithic bacteria.

    PubMed

    Bhattacharjee, Kaushik; Joshi, S R

    2016-10-01

    The study of lithic microbial communities, inhabiting rock substrates has been gathering momentum due to a growing attention of their wide importance as model systems in ecological studies and for their community structure. It is generally accepted that the success of cultivation-based technique is primarily based on suitable culture medium for isolation. The media available for enumeration and recovery of endolithic bacteria are mainly specific to particular type of rock which may not be suitable to isolate endolithic bacterial community from diverse lithobiontic niches. In this study, a new unoptimized medium was formulated, designated LM10 (unoptimized) for enumeration and recovery of endolithic bacteria by addition and/or omission of media components to the basal medium R2G, which was selected after experimental evaluation of five different existing media. The endolithic bacterial count in LM10 medium (unoptimized) was significantly higher than the R2G medium (t=-12.57, p<0.0001). The culture and nutritional parameters associated with unoptimized LM10 medium were optimized using statistical approach to maximize the recovery and enumeration of endolithic bacteria. The first phase of the study comprised of a Plackett-Burman (PB) design experiment conducted to screen thirteen medium components and two culture parameters as variables with effect on bacterial enumeration and recovery. Out of these, Yeast extract, Casein hydrolysate, Glucose, Starch and Sodium thiosulphate were found to be significantly affecting the bacterial count (p<0.05) based on PB design. On keeping rest of the media components and culture conditions at fixed value as per the PB design analyses (p>0.05 and coefficients), further optimization was carried out for significant factors using Box-Behnken design (BBD) of response surface methodology (RSM). Optimized media components obtained by BBD were Yeast extract, Casein hydrolysate, Glucose and Starch in 0.05g/l each and Sodium thiosulphate in 0

  13. Taking It Online--The Effects of Delivery Medium and Facilitator on Student Achievement in Problem-Based Learning

    ERIC Educational Resources Information Center

    Schoenfeld-Tacher, Regina; McConnell, Sherry; Kogan, Lori R.

    2004-01-01

    This study compares the effects of delivery medium (online vs. face-to-face) and facilitator content expertise on academic outcomes in a problem-based learning (PBL) course in anatomy for pre-health/medical majors. The content of online PBL sessions was examined to gain insight into the problem-solving process taking place in these situations.…

  14. Gain dynamics in a soft X-ray laser ampli er perturbed by a strong injected X-ray eld

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Yong; Wang, Shoujun; Oliva, E

    2014-01-01

    Seeding soft X-ray plasma ampli ers with high harmonics has been demonstrated to generate high-brightness soft X-ray laser pulses with full spatial and temporal coherence. The interaction between the injected coherent eld and the swept-gain medium has been modelled. However, no exper- iment has been conducted to probe the gain dynamics when perturbed by a strong external seed eld. Here, we report the rst X-ray pump X-ray probe measurement of the nonlinear response of a plasma ampli er perturbed by a strong soft X-ray ultra-short pulse. We injected a sequence of two time-delayed high-harmonic pulses (l518.9 nm) into a collisionallymore » excited nickel-like molybdenum plasma to measure with femto-second resolution the gain depletion induced by the saturated ampli cation of the high-harmonic pump and its subsequent recovery. The measured fast gain recovery in 1.5 1.75 ps con rms the possibility to generate ultra-intense, fully phase-coherent soft X-ray lasers by chirped pulse ampli cation in plasma ampli ers.« less

  15. Compositions comprising enhanced graphene oxide structures and related methods

    DOEpatents

    Kumar, Priyank Vijaya; Bardhan, Neelkanth M.; Belcher, Angela; Grossman, Jeffrey

    2016-12-27

    Embodiments described herein generally relate to compositions comprising a graphene oxide species. In some embodiments, the compositions advantageously have relatively high oxygen content, even after annealing.

  16. A Technology-Mediated Behavioral Weight Gain Prevention Intervention for College Students: Controlled, Quasi-Experimental Study

    PubMed Central

    Monroe, Courtney M; Turner-McGrievy, Gabrielle; Sundstrom, Beth; Larsen, Chelsea; Magradey, Karen; Wilcox, Sara; Brandt, Heather M

    2016-01-01

    Background Both men and women are vulnerable to weight gain during the college years, and this phenomenon is linked to an increased risk of several chronic diseases and mortality. Technology represents an attractive medium for the delivery of weight control interventions focused on college students, given its reach and appeal among this population. However, few technology-mediated weight gain prevention interventions have been evaluated for college students. Objective This study examined a new technology-based, social media-facilitated weight gain prevention intervention for college students. Methods Undergraduates (n =58) in two sections of a public university course were allocated to either a behavioral weight gain prevention intervention (Healthy Weight, HW; N=29) or a human papillomavirus (HPV) vaccination awareness intervention (control; N=29). All students were enrolled, regardless of initial body weight or expressed interest in weight management. The interventions delivered 8 lessons via electronic newsletters and Facebook postings over 9 weeks, which were designed to foster social support and introduce relevant educational content. The HW intervention targeted behavioral strategies to prevent weight gain and provided participants with a Wi-Fi-enabled scale and an electronic physical activity tracker to facilitate weight regulation. A repeated-measures analysis of variance was conducted to examine within- and between-group differences in measures of self-reported weight control practices and objectively measured weight. Use of each intervention medium and device was objectively tracked, and intervention satisfaction measures were obtained. Results Students remained weight stable (HW: −0.48+1.9 kg; control: −0.45+1.4 kg), with no significant difference between groups over 9 weeks (P =.94). However, HW students reported a significantly greater increase in the number of appropriate weight control strategies than did controls (2.1+4.5 vs −1

  17. A Technology-Mediated Behavioral Weight Gain Prevention Intervention for College Students: Controlled, Quasi-Experimental Study.

    PubMed

    West, Delia Smith; Monroe, Courtney M; Turner-McGrievy, Gabrielle; Sundstrom, Beth; Larsen, Chelsea; Magradey, Karen; Wilcox, Sara; Brandt, Heather M

    2016-06-13

    Both men and women are vulnerable to weight gain during the college years, and this phenomenon is linked to an increased risk of several chronic diseases and mortality. Technology represents an attractive medium for the delivery of weight control interventions focused on college students, given its reach and appeal among this population. However, few technology-mediated weight gain prevention interventions have been evaluated for college students. This study examined a new technology-based, social media-facilitated weight gain prevention intervention for college students. Undergraduates (n =58) in two sections of a public university course were allocated to either a behavioral weight gain prevention intervention (Healthy Weight, HW; N=29) or a human papillomavirus (HPV) vaccination awareness intervention (control; N=29). All students were enrolled, regardless of initial body weight or expressed interest in weight management. The interventions delivered 8 lessons via electronic newsletters and Facebook postings over 9 weeks, which were designed to foster social support and introduce relevant educational content. The HW intervention targeted behavioral strategies to prevent weight gain and provided participants with a Wi-Fi-enabled scale and an electronic physical activity tracker to facilitate weight regulation. A repeated-measures analysis of variance was conducted to examine within- and between-group differences in measures of self-reported weight control practices and objectively measured weight. Use of each intervention medium and device was objectively tracked, and intervention satisfaction measures were obtained. Students remained weight stable (HW: -0.48+1.9 kg; control: -0.45+1.4 kg), with no significant difference between groups over 9 weeks (P =.94). However, HW students reported a significantly greater increase in the number of appropriate weight control strategies than did controls (2.1+4.5 vs -1.1+3.4, respectively; P =.003) and there was no increase in

  18. Non-precious metal catalysts prepared from precursor comprising cyanamide

    DOEpatents

    Chung, Hoon Taek; Zelenay, Piotr

    2015-10-27

    Catalyst comprising graphitic carbon and methods of making thereof; said graphitic carbon comprising a metal species, a nitrogen-containing species and a sulfur containing species. A catalyst for oxygen reduction reaction for an alkaline fuel cell was prepared by heating a mixture of cyanamide, carbon black, and a salt selected from an iron sulfate salt and an iron acetate salt at a temperature of from about 700.degree. C. to about 1100.degree. C. under an inert atmosphere. Afterward, the mixture was treated with sulfuric acid at elevated temperature to remove acid soluble components, and the resultant mixture was heated again under an inert atmosphere at the same temperature as the first heat treatment step.

  19. Discharge-pumped cw gas lasers utilizing 'dressed-atom' gain media

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sorokin, P.P.; Glownia, J.H.; Hodgson, R.T.

    The possibility of realizing an efficient gaseous laser-beam-generating medium that utilizes {lambda}-type coherently phased (i.e., 'dressed') atoms for the active laser species, but that does not inherently require the use of external laser beams for pumping, is explored. Specifically, it is investigated if multiphoton stimulated hyper-Raman scattering (SHRS) processes driven by fluorescence radiation generated in a continuous electrical discharge present within the vapor-containing cell could produce continuous-wave (cw) optical gain at the {lambda}-atom resonance frequencies {omega}{sub o} and {omega}{sub o}{sup '}. It is deduced that such gain could result from n-photon (n{>=}4) SHRS processes only if absorption of fluorescence pumpmore » light occurs in the first three transitions of the n-photon sequence representing the process unit step. Estimates of the amount of optical gain that could be produced in such a system indicate that it should be sufficient to allow multiwatt cw laser operation to occur on one set of {lambda} transitions connecting levels in a 'double-{lambda}' structure, with the pump light being discharge-produced fluorescence centered about the transitions of the other {lambda} pair. However, to initiate operation of such a device would require injection into the laser optical cavity of intense 'starter' laser pulses at both lasing frequencies. What should be an optimal experimental configuration for determining feasibility of the proposed laser device is described. In the suggested configuration, Cs-atom 6S{sub 1/2}-6P{sub 1/2} transitions form the double-{lambda} structure.« less

  20. The Medium-Term Labor Market Returns to Community College Awards: Evidence from North Carolina. A CAPSEE Working Paper

    ERIC Educational Resources Information Center

    Belfield, Clive; Liu, Yuen Ting; Trimble, Madeline Joy

    2014-01-01

    In this paper, the authors examine the relative labor market gains for first-time college students who enrolled in the North Carolina Community College System in 2002-03. The medium-term returns to diplomas, certificates, and degrees are compared with returns for students who accumulated college credits but did not graduate. The authors also…

  1. Intensity fluctuations in bimodal micropillar lasers enhanced by quantum-dot gain competition

    NASA Astrophysics Data System (ADS)

    Leymann, H. A. M.; Hopfmann, C.; Albert, F.; Foerster, A.; Khanbekyan, M.; Schneider, C.; Höfling, S.; Forchel, A.; Kamp, M.; Wiersig, J.; Reitzenstein, S.

    2013-05-01

    We investigate correlations between orthogonally polarized cavity modes of a bimodal micropillar laser with a single layer of self-assembled quantum dots in the active region. While one emission mode of the microlaser demonstrates a characteristic S-shaped input-output curve, the output intensity of the second mode saturates and even decreases with increasing injection current above threshold. Measuring the photon autocorrelation function g(2)(τ) of the light emission confirms the onset of lasing in the first mode with g(2)(0) approaching unity above threshold. In contrast, strong photon bunching associated with superthermal values of g(2)(0) is detected for the other mode for currents above threshold. This behavior is attributed to gain competition of the two modes induced by the common gain material, which is confirmed by photon cross-correlation measurements revealing a clear anticorrelation between emission events of the two modes. The experimental studies are in qualitative agreement with theoretical studies based on a microscopic semiconductor theory, which we extend to the case of two modes interacting with the common gain medium. Moreover, we treat the problem by a phenomenological birth-death model extended to two interacting modes, which reveals that the photon probability distribution of each mode has a double-peak structure, indicating switching behavior of the modes for pump rates around threshold.

  2. Consultant-Client Relationship and Knowledge Transfer in Small- and Medium-Sized Enterprises Change Processes.

    PubMed

    Martinez, Luis F; Ferreira, Aristides I; Can, Amina B

    2016-04-01

    Based on Szulanski's knowledge transfer model, this study examined how the communicational, motivational, and sharing of understanding variables influenced knowledge transfer and change processes in small- and medium-sized enterprises, particularly under projects developed by funded programs. The sample comprised 144 entrepreneurs, mostly male (65.3%) and mostly ages 35 to 45 years (40.3%), who filled an online questionnaire measuring the variables of "sharing of understanding," "motivation," "communication encoding competencies," "source credibility," "knowledge transfer," and "organizational change." Data were collected between 2011 and 2012 and measured the relationship between clients and consultants working in a Portuguese small- and medium-sized enterprise-oriented action learning program. To test the hypotheses, structural equation modeling was conducted to identify the antecedents of sharing of understanding, motivational, and communicational variables, which were positively correlated with the knowledge transfer between consultants and clients. This transfer was also positively correlated with organizational change. Overall, the study provides important considerations for practitioners and academicians and establishes new avenues for future studies concerning the issues of consultant-client relationship and the efficacy of Government-funded programs designed to improve performance of small- and medium-sized enterprises. © The Author(s) 2016.

  3. External locus of control contributes to racial disparities in memory and reasoning training gains in ACTIVE.

    PubMed

    Zahodne, Laura B; Meyer, Oanh L; Choi, Eunhee; Thomas, Michael L; Willis, Sherry L; Marsiske, Michael; Gross, Alden L; Rebok, George W; Parisi, Jeanine M

    2015-09-01

    Racial disparities in cognitive outcomes may be partly explained by differences in locus of control. African Americans report more external locus of control than non-Hispanic Whites, and external locus of control is associated with poorer health and cognition. The aims of this study were to compare cognitive training gains between African American and non-Hispanic White participants in the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) study and determine whether racial differences in training gains are mediated by locus of control. The sample comprised 2,062 (26% African American) adults aged 65 and older who participated in memory, reasoning, or speed training. Latent growth curve models evaluated predictors of 10-year cognitive trajectories separately by training group. Multiple group modeling examined associations between training gains and locus of control across racial groups. Compared to non-Hispanic Whites, African Americans evidenced less improvement in memory and reasoning performance after training. These effects were partially mediated by locus of control, controlling for age, sex, education, health, depression, testing site, and initial cognitive ability. African Americans reported more external locus of control, which was associated with smaller training gains. External locus of control also had a stronger negative association with reasoning training gain for African Americans than for Whites. No racial difference in training gain was identified for speed training. Future intervention research with African Americans should test whether explicitly targeting external locus of control leads to greater cognitive improvement following cognitive training. (c) 2015 APA, all rights reserved).

  4. Fibrous composites comprising carbon nanotubes and silica

    DOEpatents

    Peng, Huisheng [Shanghai, CN; Zhu, Yuntian Theodore [Cary, NC; Peterson, Dean E [Los Alamos, NM; Jia, Quanxi [Los Alamos, NM

    2011-10-11

    Fibrous composite comprising a plurality of carbon nanotubes; and a silica-containing moiety having one of the structures: (SiO).sub.3Si--(CH.sub.2).sub.n--NR.sub.1R.sub.2) or (SiO).sub.3Si--(CH.sub.2).sub.n--NCO; where n is from 1 to 6, and R.sub.1 and R.sub.2 are each independently H, CH.sub.3, or C.sub.2H.sub.5.

  5. Nanophosphor composite scintillators comprising a polymer matrix

    DOEpatents

    Muenchausen, Ross Edward; Mckigney, Edward Allen; Gilbertson, Robert David

    2010-11-16

    An improved nanophosphor composite comprises surface modified nanophosphor particles in a solid matrix. The nanophosphor particle surface is modified with an organic ligand, or by covalently bonding a polymeric or polymeric precursor material. The surface modified nanophosphor particle is essentially charge neutral, thereby preventing agglomeration of the nanophosphor particles during formation of the composite material. The improved nanophosphor composite may be used in any conventional scintillator application, including in a radiation detector.

  6. Method to fabricate silicon chromatographic column comprising fluid ports

    DOEpatents

    Manginell, Ronald P.; Frye-Mason, Gregory C.; Heller, Edwin J.; Adkins, Douglas R.

    2004-03-02

    A new method for fabricating a silicon chromatographic column comprising through-substrate fluid ports has been developed. This new method enables the fabrication of multi-layer interconnected stacks of silicon chromatographic columns.

  7. Two-dimensional photonic crystal bandedge laser with hybrid perovskite thin film for optical gain

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cha, Hyungrae; Inter-University Semiconductor Research Center, Seoul National University, Seoul 08826; Bae, Seunghwan

    2016-05-02

    We report optically pumped room temperature single mode laser that contains a thin film of hybrid perovskite, an emerging photonic material, as gain medium. Two-dimensional square lattice photonic crystal (PhC) backbone structure enables single mode laser operation via a photonic bandedge mode, while a thin film of methyl-ammonium lead iodide (CH{sub 3}NH{sub 3}PbI{sub 3}) spin-coated atop provides optical gain for lasing. Two kinds of bandedge modes, Γ and M, are employed, and both devices laser in single mode at similar laser thresholds of ∼200 μJ/cm{sup 2} in pulse energy density. Polarization dependence measurements reveal a clear difference between the two kindsmore » of bandedge lasers: isotropic for the Γ-point laser and highly anisotropic for the M-point laser. These observations are consistent with expected modal properties, confirming that the lasing actions indeed originate from the corresponding PhC bandedge modes.« less

  8. Comparing gains and losses.

    PubMed

    McGraw, A Peter; Larsen, Jeff T; Kahneman, Daniel; Schkade, David

    2010-10-01

    Loss aversion in choice is commonly assumed to arise from the anticipation that losses have a greater effect on feelings than gains, but evidence for this assumption in research on judged feelings is mixed. We argue that loss aversion is present in judged feelings when people compare gains and losses and assess them on a common scale. But many situations in which people judge and express their feelings lack these features. When judging their feelings about an outcome, people naturally consider a context of similar outcomes for comparison (e.g., they consider losses against other losses). This process permits gains and losses to be normed separately and produces psychological scale units that may not be the same in size or meaning for gains and losses. Our experiments show loss aversion in judged feelings for tasks that encourage gain-loss comparisons, but not tasks that discourage them, particularly those using bipolar scales.

  9. The Calibration of AVHRR Visible Dual Gain using Meteosat-8 for NOAA-16 to 18

    NASA Technical Reports Server (NTRS)

    Doelling, David R.; Garber, Donald P.; Avey, L. A.; Nguyen, Louis; Minnis, Patrick

    2007-01-01

    The NOAA AVHRR program has given the remote sensing community over 25 years of imager radiances to retrieve global cloud, vegetation, and aerosol properties. This dataset can be used for long-term climate research, if the AVHRR instrument is well calibrated. Unfortunately, the AVHRR instrument does not have onboard visible calibration and does degrade over time. Vicarious post-launch calibration is necessary to obtain cloud properties that are not biased over time. The recent AVHRR-3 instrument has a dual gain in the visible channels in order to achieve greater radiance resolution in the clear-sky. This has made vicarious calibration of the AVHRR-3 more difficult to unravel. Reference satellite radiances from well-calibrated instruments, usually equipped with solar diffusers, such as MODIS, have been used to successfully vicariously calibrate other visible instruments. Transfer of calibration from one satellite to another using co-angled, collocated, coincident radiances has been well validated. Terra or Aqua MODIS and AVHRR comparisons can only be performed over the poles during summer. However, geostationary satellites offer a transfer medium that captures both parts of the dual gain. This AVHRR-3 calibration strategy uses, calibrated with MODIS, Meteosat-8 radiances simultaneously to determine the dual gains using 50km regions. The dual gain coefficients will be compared with the nominal coefficients. Results will be shown for all visible channels for NOAA-17.

  10. Olanzapine causes hypothermia, inactivity, a deranged feeding pattern and weight gain in female Wistar rats.

    PubMed

    Evers, S S; Calcagnoli, F; van Dijk, G; Scheurink, A J W

    2010-11-01

    Olanzapine is an a-typical antipsychotic drug antagonizing predominantly 5-HT and dopamine, but also histamine, muscarin, and α-adrenergic receptors. In humans, Olanzapine induces weight gain and increases the risk of type 2 diabetes. The underlying mechanisms of Olanzapine-induced weight gain are unclear. To study this we administered Olanzapine (5mg/kg) in female Wistar rats on a medium fat diet for 14 days via a permanent gastric catheter twice a day, just prior to the onset and at the middle of dark phase. Food and water intake, locomotor activity and body temperature were measured. Olanzapine acutely induced hypothermia, markedly decreased locomotor activity and increased body weight during 14 days of treatment. Olanzapine treatment did not result in an alteration of 24h food intake, but diurnal patterns of feeding behavior and body temperature were dramatically changed. We conclude that in female Wistar rats Olanzapine has an acute hypothermic effect, that the effect of Olanzapine on feeding behavior is secondary to the effect on activity, and that Olanzapine-induced weight gain is primarily the result of reduction in locomotor activity. Copyright © 2010 Elsevier Inc. All rights reserved.

  11. Thermal emitter comprising near-zero permittivity materials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Luk, Ting S.; Campione, Salvatore; Sinclair, Michael B.

    A novel thermal source comprising a semiconductor hyperbolic metamaterial provides control of the emission spectrum and the angular emission pattern. These properties arise because of epsilon-near-zero conditions in the semiconductor hyperbolic metamaterial. In particular, the thermal emission is dominated by the epsilon-near-zero effect in the doped quantum wells composing the semiconductor hyperbolic metamaterial. Furthermore, different properties are observed for s and p polarizations, following the characteristics of the strong anisotropy of hyperbolic metamaterials.

  12. The Institutional Design for Continuing Education in the "National Medium- and Long-Term Educational Reform and Development Guideline (2010-20)"

    ERIC Educational Resources Information Center

    Mingming, Ji

    2012-01-01

    The cause of continuing education has gained significant strides in China after the advent of Reform and Opening Up, but it is still the weakest link in the current system of education. The "National Medium- and Long-Term Educational Reform and Development Guideline (2010-20)" (hereafter abbreviated as the "Guideline") has…

  13. Propagation and scattering of vector light beam in turbid scattering medium

    NASA Astrophysics Data System (ADS)

    Doronin, Alexander; Milione, Giovanni; Meglinski, Igor; Alfano, Robert R.

    2014-03-01

    Due to its high sensitivity to subtle alterations in medium morphology the vector light beams have recently gained much attention in the area of photonics. This leads to development of a new non-invasive optical technique for tissue diagnostics. Conceptual design of the particular experimental systems requires careful selection of various technical parameters, including beam structure, polarization, coherence, wavelength of incident optical radiation, as well as an estimation of how the spatial and temporal structural alterations in biological tissues can be distinguished by variations of these parameters. Therefore, an accurate realistic description of vector light beams propagation within tissue-like media is required. To simulate and mimic the propagation of vector light beams within the turbid scattering media the stochastic Monte Carlo (MC) technique has been used. In current report we present the developed MC model and the results of simulation of different vector light beams propagation in turbid tissue-like scattering media. The developed MC model takes into account the coherent properties of light, the influence of reflection and refraction at the medium boundary, helicity flip of vortexes and their mutual interference. Finally, similar to the concept of higher order Poincaŕe sphere (HOPS), to link the spatial distribution of the intensity of the backscattered vector light beam and its state of polarization on the medium surface we introduced the color-coded HOPS.

  14. Active rc filter permits easy trade-off of amplifier gain and sensitivity to gain

    NASA Technical Reports Server (NTRS)

    Kerwin, W. J.; Shaffer, C. V.

    1968-01-01

    Passive RC network was designed with zeros of transmission in the right half of the complex frequency plane in the feedback loop of a simple negative-gain amplifier. The proper positioning provides any desired trade-off between amplifier gain and sensitivity to amplifier gain.

  15. Photovoltaic device comprising compositionally graded intrinsic photoactive layer

    DOEpatents

    Hoffbauer, Mark A; Williamson, Todd L

    2013-04-30

    Photovoltaic devices and methods of making photovoltaic devices comprising at least one compositionally graded photoactive layer, said method comprising providing a substrate; growing onto the substrate a uniform intrinsic photoactive layer having one surface disposed upon the substrate and an opposing second surface, said intrinsic photoactive layer consisting essentially of In.sub.1-xA.sub.xN,; wherein: i. 0.ltoreq.x.ltoreq.1; ii. A is gallium, aluminum, or combinations thereof; and iii. x is at least 0 on one surface of the intrinsic photoactive layer and is compositionally graded throughout the layer to reach a value of 1 or less on the opposing second surface of the layer; wherein said intrinsic photoactive layer is isothermally grown by means of energetic neutral atom beam lithography and epitaxy at a temperature of 600.degree. C. or less using neutral nitrogen atoms having a kinetic energy of from about 1.0 eV to about 5.0 eV, and wherein the intrinsic photoactive layer is grown at a rate of from about 5 nm/min to about 100 nm/min.

  16. Pigment production on L-tryptophan medium by Cryptococcus gattii and Cryptococcus neoformans.

    PubMed

    Chaskes, Stuart; Cammer, Michael; Nieves, Edward; Casadevall, Arturo

    2014-01-01

    In recent years strains previously grouped within Cryptococcus neoformans have been divided into two species C. neoformans and C. gattii, with Cryptococcus neoformans comprising serotypes A, D, and AD and C. gattii comprising serotypes B and C. Cryptococcus neoformans have also been subdivided into two varieties C. neoformans var. grubii, serotype A, and C. neoformans var. neoformans, serotype D. We analyzed the growth and pigment production characteristics of 139 strains of Cryptococcus spp. in L-tryptophan containing media. Nearly all strains of Cryptococcus, including each variety and serotype tested produced a pink water-soluble pigment (molecular weight of 535.2 Da) from L-tryptophan. Consequently, the partial separation of the species was based on whether the pink pigment was secreted into the medium (extracellular) or retained as an intracellular pigment. On L-tryptophan medium C. neoformans var. grubii and serotype AD produced a pink extracellular pigment. In contrast, for C. gattii, the pink pigment was localized intracellularly and masked by heavy production of brown pigments. Pigment production by C. neoformans var. neoformans was variable with some strains producing the pink extracellular pigment and others retained the pink pigment intracellularly. The pink intracellular pigment produced by strains of C. neoformans var. neoformans was masked by production of brown pigments. Cryptococcus laccase mutants failed to produce pigments from L-tryptophan. This is the first report that the enzyme laccase is involved in tryptophan metabolism. Prior to this report Cryptococcus laccase produced melanin or melanin like-pigments from heterocyclic compounds that contained ortho or para diphenols, diaminobenzenes and aminophenol compounds. The pigments produced from L-tryptophan were not melanin.

  17. Pigment Production on L-Tryptophan Medium by Cryptococcus gattii and Cryptococcus neoformans

    PubMed Central

    Chaskes, Stuart; Cammer, Michael; Nieves, Edward; Casadevall, Arturo

    2014-01-01

    In recent years strains previously grouped within Cryptococcus neoformans have been divided into two species C. neoformans and C. gattii, with Cryptococcus neoformans comprising serotypes A, D, and AD and C. gattii comprising serotypes B and C. Cryptococcus neoformans have also been subdivided into two varieties C. neoformans var. grubii, serotype A, and C. neoformans var. neoformans, serotype D. We analyzed the growth and pigment production characteristics of 139 strains of Cryptococcus spp. in L-tryptophan containing media. Nearly all strains of Cryptococcus, including each variety and serotype tested produced a pink water-soluble pigment (molecular weight of 535.2 Da) from L-tryptophan. Consequently, the partial separation of the species was based on whether the pink pigment was secreted into the medium (extracellular) or retained as an intracellular pigment. On L-tryptophan medium C. neoformans var. grubii and serotype AD produced a pink extracellular pigment. In contrast, for C. gattii, the pink pigment was localized intracellularly and masked by heavy production of brown pigments. Pigment production by C. neoformans var. neoformans was variable with some strains producing the pink extracellular pigment and others retained the pink pigment intracellularly. The pink intracellular pigment produced by strains of C. neoformans var. neoformans was masked by production of brown pigments. Cryptococcus laccase mutants failed to produce pigments from L-tryptophan. This is the first report that the enzyme laccase is involved in tryptophan metabolism. Prior to this report Cryptococcus laccase produced melanin or melanin like-pigments from heterocyclic compounds that contained ortho or para diphenols, diaminobenzenes and aminophenol compounds. The pigments produced from L-tryptophan were not melanin. PMID:24736553

  18. Improved Gain Microstrip Patch Antenna

    DTIC Science & Technology

    2015-08-06

    08-2015 Publication Improved Gain Microstrip Patch Antenna David A. Tonn Naval Under Warfare Center Division, Newport 1176 Howell St., Code 00L...GAIN MICROSTRIP PATCH ANTENNA STATEMENT OF GOVERNMENT INTEREST [0001] The invention described herein may be manufactured and used by or for the...patch antenna having increased gain, and an apparatus for increasing the gain and bandwidth of an existing microstrip patch antenna . (2) Description

  19. Numerical Investigations of Moisture Distribution in a Selected Anisotropic Soil Medium

    NASA Astrophysics Data System (ADS)

    Iwanek, M.

    2018-01-01

    The moisture of soil profile changes both in time and space and depends on many factors. Changes of the quantity of water in soil can be determined on the basis of in situ measurements, but numerical methods are increasingly used for this purpose. The quality of the results obtained using pertinent software packages depends on appropriate description and parameterization of soil medium. Thus, the issue of providing for the soil anisotropy phenomenon gains a big importance. Although anisotropy can be taken into account in many numerical models, isotopic soil is often assumed in the research process. However, this assumption can be a reason for incorrect results in the simulations of water changes in soil medium. In this article, results of numerical simulations of moisture distribution in the selected soil profile were presented. The calculations were conducted assuming isotropic and anisotropic conditions. Empirical verification of the results obtained in the numerical investigations indicated statistical essential discrepancies for the both analyzed conditions. However, better fitting measured and calculated moisture values was obtained for the case of providing for anisotropy in the simulation model.

  20. A Simplified Model for Detonation Based Pressure-Gain Combustors

    NASA Technical Reports Server (NTRS)

    Paxson, Daniel E.

    2010-01-01

    A time-dependent model is presented which simulates the essential physics of a detonative or otherwise constant volume, pressure-gain combustor for gas turbine applications. The model utilizes simple, global thermodynamic relations to determine an assumed instantaneous and uniform post-combustion state in one of many envisioned tubes comprising the device. A simple, second order, non-upwinding computational fluid dynamic algorithm is then used to compute the (continuous) flowfield properties during the blowdown and refill stages of the periodic cycle which each tube undergoes. The exhausted flow is averaged to provide mixed total pressure and enthalpy which may be used as a cycle performance metric for benefits analysis. The simplicity of the model allows for nearly instantaneous results when implemented on a personal computer. The results compare favorably with higher resolution numerical codes which are more difficult to configure, and more time consuming to operate.

  1. Non-aqueous liquid compositions comprising ion exchange polymers

    DOEpatents

    Kim, Yu Seung; Lee, Kwan-Soo; Rockward, Tommy Q. T.

    2013-03-12

    Compositions, and methods of making thereof, comprising from about 1% to about 5% of a perfluorinated sulfonic acid ionomer or a hydrocarbon-based ionomer; and from about 95% to about 99% of a solvent, said solvent consisting essentially of a polyol; wherein said composition is substantially free of water and wherein said ionomer is uniformly dispersed in said solvent.

  2. Non-aqueous liquid compositions comprising ion exchange polymers

    DOEpatents

    Kim, Yu Seung [Los Alamos, NM; Lee, Kwan-Soo [Blacksburg, VA; Rockward, Tommy Q. T. [Rio Rancho, NM

    2011-07-19

    Compositions, and methods of making thereof, comprising from about 1% to about 5% of a perfluorinated sulfonic acid ionomer or a hydrocarbon-based ionomer; and from about 95% to about 99% of a solvent, said solvent consisting essentially of a polyol; wherein said composition is substantially free of water and wherein said ionomer is uniformly dispersed in said solvent.

  3. Unequal Gain of Equal Resources across Racial Groups.

    PubMed

    Assari, Shervin

    2017-08-05

    The health effects of economic resources (eg, education, employment, and living place) and psychological assets (eg, self-efficacy, perceived control over life, anger control, and emotions) are well-known. This article summarizes the results of a growing body of evidence documenting Blacks' diminished return, defined as a systematically smaller health gain from economic resources and psychological assets for Blacks in comparison to Whites. Due to structural barriers that Blacks face in their daily lives, the very same resources and assets generate smaller health gain for Blacks compared to Whites. Even in the presence of equal access to resources and assets, such unequal health gain constantly generates a racial health gap between Blacks and Whites in the United States. In this paper, a number of public policies are recommended based on these findings. First and foremost, public policies should not merely focus on equalizing access to resources and assets, but also reduce the societal and structural barriers that hinder Blacks. Policy solutions should aim to reduce various manifestations of structural racism including but not limited to differential pay, residential segregation, lower quality of education, and crime in Black and urban communities. As income was not found to follow the same pattern demonstrated for other resources and assets (ie, income generated similar decline in risk of mortality for Whites and Blacks), policies that enforce equal income and increase minimum wage for marginalized populations are essential. Improving quality of education of youth and employability of young adults will enable Blacks to compete for high paying jobs. Policies that reduce racism and discrimination in the labor market are also needed. Without such policies, it will be very difficult, if not impossible, to eliminate the sustained racial health gap in the United States. © 2018 The Author(s); Published by Kerman University of Medical Sciences. This is an open

  4. High-gain subnanowatt power consumption hybrid complementary logic inverter with WSe2 nanosheet and ZnO nanowire transistors on glass.

    PubMed

    Shokouh, Seyed Hossein Hosseini; Pezeshki, Atiye; Ali Raza, Syed Raza; Lee, Hee Sung; Min, Sung-Wook; Jeon, Pyo Jin; Shin, Jae Min; Im, Seongil

    2015-01-07

    A 1D-2D hybrid complementary logic inverter comprising of ZnO nanowire and WSe2 nanosheet field-effect transistors (FETs) is fabricated on glass, which shows excellent static and dynamic electrical performances with a voltage gain of ≈60, sub-nanowatt power consumption, and at least 1 kHz inverting speed. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Coated phosphors, methods of making them, and articles comprising the same

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lyons, Robert Joseph

    Compositions comprising a phosphor and a compound having the formula R.sub.1R.sub.2M, wherein R.sub.1 is a substituted or unsubstituted alkyl, aryl, heteroaryl, arylalkyl, heteroarylalkyl, alkoxy, alkoxyl, acyl heterocycle, haloalkyl, oxaalkyl, or silyl; R.sub.2 is a sulfate, sulfonate, or carboxylate and M is an alkali metal or an alkaline earth metal are provided. Phosphors coated with the compound, methods of making the coated phosphors and articles comprising the compositions are provided.

  6. Brain Network Modularity Predicts Exercise-Related Executive Function Gains in Older Adults

    PubMed Central

    Baniqued, Pauline L.; Gallen, Courtney L.; Voss, Michelle W.; Burzynska, Agnieszka Z.; Wong, Chelsea N.; Cooke, Gillian E.; Duffy, Kristin; Fanning, Jason; Ehlers, Diane K.; Salerno, Elizabeth A.; Aguiñaga, Susan; McAuley, Edward; Kramer, Arthur F.; D'Esposito, Mark

    2018-01-01

    Recent work suggests that the brain can be conceptualized as a network comprised of groups of sub-networks or modules. The extent of segregation between modules can be quantified with a modularity metric, where networks with high modularity have dense connections within modules and sparser connections between modules. Previous work has shown that higher modularity predicts greater improvements after cognitive training in patients with traumatic brain injury and in healthy older and young adults. It is not known, however, whether modularity can also predict cognitive gains after a physical exercise intervention. Here, we quantified modularity in older adults (N = 128, mean age = 64.74) who underwent one of the following interventions for 6 months (NCT01472744 on ClinicalTrials.gov): (1) aerobic exercise in the form of brisk walking (Walk), (2) aerobic exercise in the form of brisk walking plus nutritional supplement (Walk+), (3) stretching, strengthening and stability (SSS), or (4) dance instruction. After the intervention, the Walk, Walk+ and SSS groups showed gains in cardiorespiratory fitness (CRF), with larger effects in both walking groups compared to the SSS and Dance groups. The Walk, Walk+ and SSS groups also improved in executive function (EF) as measured by reasoning, working memory, and task-switching tests. In the Walk, Walk+, and SSS groups that improved in EF, higher baseline modularity was positively related to EF gains, even after controlling for age, in-scanner motion and baseline EF. No relationship between modularity and EF gains was observed in the Dance group, which did not show training-related gains in CRF or EF control. These results are consistent with previous studies demonstrating that individuals with a more modular brain network organization are more responsive to cognitive training. These findings suggest that the predictive power of modularity may be generalizable across interventions aimed to enhance aspects of cognition and that

  7. Total cost comparison of standard antenatal care with a weight gain restriction programme for obese pregnant women.

    PubMed

    de Keyser, N; Josefsson, A; Monfils, W G; Claesson, I M; Carlsson, P; Sydsjö, A; Sydsjö, G

    2011-05-01

    To perform a cost comparison of a weight gain restriction programme for obese pregnant women with standard antenatal care, and to identify if there were differences in healthcare costs within the intervention group related to degree of gestational weight gain or degree of obesity at programme entry. A comparison of mean healthcare costs for participants of an intervention study at antenatal care clinics with controls in south-east Sweden. In total, 155 women in an intervention group attempted to restrict their gestational weight gain to <7 kg. The control group comprised 193 women. Mean costs during pregnancy, delivery and the neonatal period were compared with the costs of standard care. Costs were converted from Swedish Kronor to Euros (€). Healthcare costs during pregnancy were lower in the intervention group. There was no significant difference in total healthcare costs (i.e. sum of costs during pregnancy, delivery and the neonatal period) between the intervention group and the control group. Within the intervention group, the subgroup that gained 4.5-9.5 kg had the lowest costs. The total cost, including intervention costs, was € 1283 more per woman/infant in the intervention group compared with the control group (P=0.025). The degree of obesity at programme entry had no bearing on the outcome. The weight gain restriction programme for obese pregnant women was effective in restricting gestational weight gain to <7 kg, but had a higher total cost compared with standard antenatal care. Copyright © 2011 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  8. Poststapedectomy hearing gain: comparison of a Teflon (fluoroplastic ASTM F 754) prosthesis with a Schuknecht-type wire/Teflon prosthesis.

    PubMed

    Zepeda-López, Emilia Guadalupe; Bello-Mora, Antonio; Félix-Trujillo, Manuel Martín

    2005-11-01

    We conducted a retrospective study to compare poststapedectomy hearing gain in study-eligible patients who had received a Teflon (fluoroplastic ASTM F 754) prosthesis (study group; n = 76) with hearing gain achieved in a matched group (by age, sex, and degree of hypoacusis) of patients who had received a Schuknecht-type wire/Teflon prosthesis (control group; n = 70). All procedures had been performed by the authors at our institution between Jan. 2, 1994, and Dec. 31, 1997. Airway averages at low, medium, and high frequencies were estimated on the basis ofpre- and postoperative audiologic evaluations, as were total air-bone gaps at 7 frequencies between 125 and 8, 000 Hz. We found that the study group achieved a significantly greater degree of hearing gain at 125 and 250 Hz and significantly better closure of the air-bone gap at 250, 500, 1,000, 2,000, and 4,000 Hz. The hearing outcomes among patients in the study group were excellent.

  9. Association of gestational weight gain expectations with advice on actual weight gain

    USDA-ARS?s Scientific Manuscript database

    To examine pregnant women's gestational weight gain expectations/advice from various sources (i.e., self, family/friends, physician) and the impact of these sources of expectations/advice on actual measured gestational weight gain. Pregnant women (n=230, 87.4% Caucasian, second pregnancy) in a cohor...

  10. Increasing the formability of ferritic stainless steel tube by granular medium-based hot forming

    NASA Astrophysics Data System (ADS)

    Chen, H.; Staupendahl, D.; Hiegemann, L.; Tekkaya, A. E.

    2017-09-01

    Ferritic stainless steel without the alloy constituent nickel is an economical substitution for austenitic stainless steel in the automotive industry. Its lower formability, however, oftentimes prevents the direct material substitution in forming processes such as hydroforming, necessitating new forming strategies. To extend the forming capacity of ferritic stainless steel tube, the approach of forming at elevated temperatures is proposed. Utilizing granular material as forming medium, high forming temperatures up to 900°C are realized. The forming process works by moving punches axially into the granular medium, thereby, compressing it and causing axial as well as radial pressure. In experimental and numerical investigations it is shown that interfacial friction between the granular medium and the tube inherently causes tube feed, resulting in stain states in the tension-compression region of the FLD. Formability data for this region are gained by notched tensile tests, which are performed at room temperature as well as at elevated temperatures. The measured data show that the formability is improved at forming temperatures higher than 700°C. This observed formability increase is experimentally validated using a demonstrator geometry, which reaches expansion ratios that show fracture in specimens formed at room temperature.

  11. Weight Gain during Pregnancy

    MedlinePlus

    ... Global Map Premature Birth Report Cards Careers Archives Pregnancy Before or between pregnancies Nutrition, weight & fitness Prenatal ... fitness > Weight gain during pregnancy Weight gain during pregnancy E-mail to a friend Please fill in ...

  12. Asthma Triggers: Gain Control

    MedlinePlus

    ... Centers Asthma Contact Us Share Asthma Triggers: Gain Control Breathing Freely: Controlling Asthma Triggers This video features ... Air Quality: Biological Pollutants Help Your Child Gain Control Over Asthma Top of Page Molds About Molds ...

  13. Water quality in Gaines Creek and Gaines Creek arm of Eufaula Lake, Oklahoma

    USGS Publications Warehouse

    Kurklin, J.K.

    1990-01-01

    Based on samples collected from May 1978 to May 1980 and analyzed for major anions, nitrogen, trace elements, phytoplankton, and bacteria, the water in Gaines Creek and the Gaines Creek arm of Eufaula Lake was similar with respect to suitability for municipal use. Water from Gaines Creek had a pH range of 5.7 to 7.6 and a maximum specific conductance of 97 microsiemens per centimeter at 25o Celsius, whereas water from the Gaines Creek arm of Eufaula Lake had a pH range of 6.0 to 9.2 and a maximum specific conductance of 260 microsiemens per centimeter at 25o Celsius. Dissolved oxygen, pH, temperature, and specific conductance values for the lake varied with depth. With the exceptions of cadmium, iron, lead, and manganese, trace-element determinations of samples were within recommended national primary and secondary drinking-water standards. When compared to the National Academy of Sciences water-quality criteria, phytoplankton and bacteria counts exceeded recommendations; however, water from either Gaines Creek or Eufaula Lake could be treated similarly and used as a municipal water supply.

  14. Numerical simulations of the optical gain of crystalline fiber doped by rare earth and transition ion

    NASA Astrophysics Data System (ADS)

    Daoui, A. K.; Boubir, B.; Adouane, A.; Demagh, N.; Ghoumazi, M.

    2015-02-01

    A fiber laser is a laser whose gain medium is a doped fiber, although lasers whose cavity is made wholly of fibers have also been called fiber lasers. The gain media in a fiber laser is usually fiber doped with rare-earth ions, such as erbium (Er), neodymium (Nd), ytterbium (Yb), thulium (Tm), or praseodymium (Pr), which is doped into the core of the optical fiber, similar to those used to transmit telecommunications signals. Fiber lasers find many applications in materials processing, including cutting, welding, drilling, and marking metal. To maximize their market penetration, it is necessary to increase their output power. In this work, we present a detailed study based on the numerical simulation using MATLAB, of one of the principal characteristics of a fiber laser doped with rare earth ions and transition ion. The gain depends on several parameters such as the length of the doped fiber, the density, the pump power, noise, etc.). The used program resolves the state equations in this context together with those governing the light propagation phenomena. The developed code can also be used to study the dynamic operating modes of a doped fiber laser.

  15. Two new families of high-gain dc-dc power electronic converters for dc-microgrids

    NASA Astrophysics Data System (ADS)

    Prabhala, Venkata Anand Kishore

    Distributing the electric power in dc form is an appealing solution in many applications such as telecommunications, data centers, commercial buildings, and microgrids. A high gain dc-dc power electronic converter can be used to individually link low-voltage elements such as solar panels, fuel cells, and batteries to the dc voltage bus which is usually 400 volts. This way, it is not required to put such elements in a series string to build up their voltages. Consequently, each element can function at it optimal operating point regardless of the other elements in the system. In this dissertation, first a comparative study of dc microgrid architectures and their advantages over their ac counterparts is presented. Voltage level selection of dc distribution systems is discussed from the cost, reliability, efficiency, and safety standpoints. Next, a new family of non-isolated high-voltage-gain dc-dc power electronic converters with unidirectional power flow is introduced. This family of converters benefits from a low voltage stress across its switches. The proposed topologies are versatile as they can be utilized as single-input or double-input power converters. In either case, they draw continuous currents from their sources. Lastly, a bidirectional high-voltage-gain dc-dc power electronic converter is proposed. This converter is comprised of a bidirectional boost converter which feeds a switched-capacitor architecture. The switched-capacitor stage suggested here has several advantages over the existing approaches. For example, it benefits from a higher voltage gain while it uses less number of capacitors. The proposed converters are highly efficient and modular. The operating modes, dc voltage gain, and design procedure for each converter are discussed in details. Hardware prototypes have been developed in the lab. The results obtained from the hardware agree with those of the simulation models.

  16. A method to estimate the biomass of Spirulina platensis cultivated on a solid medium.

    PubMed

    Pelizer, Lúcia Helena; Moraes, Iracema de Oliveira

    2014-01-01

    This paper presents a method to estimate the biomass of Spirulina cultivated on solid medium with sugarcane bagasse as a support, in view of the difficulty in determining biomass concentrations in bioprocesses, particularly those conducted in semi-solid or solid media. The genus Spirulina of the family Oscillatoriaceae comprises the group of multicellular filamentous cyanobacteria (blue-green microalgae). Spirulina is used as fish feed in aquaculture, as a food supplement, a source of vitamins, pigments, antioxidants and fatty acids. Therefore, its growth parameters are extremely important in studies of the development and optimization of bioprocesses. For studies of biomass growth, Spirulina platensis was cultured on solid medium using sugarcane bagasse as a support. The biomass thus produced was estimated by determining the protein content of the material grown during the process, based on the ratio of dry weight to protein content obtained in the surface growth experiments. The protein content of the biomass grown in Erlenmeyer flasks on surface medium was examined daily to check the influence of culture time on the protein content of the biomass. The biomass showed an average protein content of 42.2%. This methodology enabled the concentration of biomass adhering to the sugarcane bagasse to be estimated from the indirect measurement of the protein content associated with cell growth.

  17. Potential of gene drives with genome editing to increase genetic gain in livestock breeding programs.

    PubMed

    Gonen, Serap; Jenko, Janez; Gorjanc, Gregor; Mileham, Alan J; Whitelaw, C Bruce A; Hickey, John M

    2017-01-04

    This paper uses simulation to explore how gene drives can increase genetic gain in livestock breeding programs. Gene drives are naturally occurring phenomena that cause a mutation on one chromosome to copy itself onto its homologous chromosome. We simulated nine different breeding and editing scenarios with a common overall structure. Each scenario began with 21 generations of selection, followed by 20 generations of selection based on true breeding values where the breeder used selection alone, selection in combination with genome editing, or selection with genome editing and gene drives. In the scenarios that used gene drives, we varied the probability of successfully incorporating the gene drive. For each scenario, we evaluated genetic gain, genetic variance [Formula: see text], rate of change in inbreeding ([Formula: see text]), number of distinct quantitative trait nucleotides (QTN) edited, rate of increase in favourable allele frequencies of edited QTN and the time to fix favourable alleles. Gene drives enhanced the benefits of genome editing in seven ways: (1) they amplified the increase in genetic gain brought about by genome editing; (2) they amplified the rate of increase in the frequency of favourable alleles and reduced the time it took to fix them; (3) they enabled more rapid targeting of QTN with lesser effect for genome editing; (4) they distributed fixed editing resources across a larger number of distinct QTN across generations; (5) they focussed editing on a smaller number of QTN within a given generation; (6) they reduced the level of inbreeding when editing a subset of the sires; and (7) they increased the efficiency of converting genetic variation into genetic gain. Genome editing in livestock breeding results in short-, medium- and long-term increases in genetic gain. The increase in genetic gain occurs because editing increases the frequency of favourable alleles in the population. Gene drives accelerate the increase in allele frequency

  18. Leading Gainful Employment Metric Reporting

    ERIC Educational Resources Information Center

    Powers, Kristina; MacPherson, Derek

    2016-01-01

    This chapter will address the importance of intercampus involvement in reporting of gainful employment student-level data that will be used in the calculation of gainful employment metrics by the U.S. Department of Education. The authors will discuss why building relationships within the institution is critical for effective gainful employment…

  19. Karyotypes of some medium-sized Dytiscidae (Agabinae and Colymbetinae) (Coleoptera)

    PubMed Central

    Angus, Robert B.; Clery, Molly J.; Carter, Jodie C.; Wenczek, Daniel E.

    2013-01-01

    Abstract An account is given of the karyotypes of 29 species of medium sized Dytiscidae (Coleoptera). Of the 20 species of Agabus Leach, 1817, 18 have karyotypes comprising 21 pairs of autosomes and sex chromosomes which are either X0(♂) or XX (♀). These species are Agabus serricornis (Paykull, 1799), Agabus labiatus (Brahm, 1791), Agabus congener (Thunberg, 1794), Agabus lapponicus (Thomson, 1867), Agabus thomsoni (J. Sahlberg, 1871), Agabus confinis (Gyllenhal, 1808), Agabus sturmii (Gyllenhal, 1808), Agabus bipustulatus (Linnaeus, 1767), Agabus nevadensis Håkan Lindberg, 1939, Agabus wollastoni Sharp, 1882, Agabus melanarius Aubé, 1837, Agabus biguttatus (Olivier, 1795), Agabus binotatus Aubé, 1837, Agabus affinis (Paykull, 1798), Agabus unguicularis (Thomson, 1867), Agabus ramblae Millan & Ribera, 2001, Agabus conspersus (Marsham, 1802) and Agabus nebulosus (Forster, 1771). However two species, Agabus infuscatus Aubé, 1838 and Agabus adpressus Aubé, 1837, have developed a neo-XY system, with karyotypes comprising 21 pairs of autosomes and XY sex chromosomes (♂). No chromosomal differences have been detected between typical Agabus bipustulatus and Agabus bipustulatus var. solieri Aubé, 1837, nor have any been found between the three species of the Agabus bipustulatus complex (Agabus bipustulatus, Agabus nevadensis and Agabus wollastoni). The four species of Colymbetes Clairville, 1806, Colymbetes fuscus (Linnaeus, 1758), Colymbetes paykulli Erichson, 1837, Colymbetes piceus Klug, 1834 and Colymbetes striatus (Linnaeus, 1758) have karyotypes comprising 20 pairs of autosomes and sex chromosomes which are X0 (♂), XX (♀). Two of the species of Rhantus Dejean, 1833, Rhantus exsoletus (Forster, 1771) and Rhantus suturellus (Harris, 1828) have karyotypes comprising 20 pairs of autosomes and X0/XX sex chromosomes, but the other three species, Rhantus grapii (Gyllenhal, 1808), Rhantus frontalis (Marsham, 1802) and Rhantus suturalis (Macleay, 1825) have 22

  20. Development of orally disintegrating tablets comprising controlled-release multiparticulate beads

    PubMed Central

    2012-01-01

    Melperone is an atypical antipsychotic agent that has shown a wide spectrum of neuroleptic properties, particularly effective in the treatment of senile dementia and Parkinson’s-associated psychosis, and is marketed in Europe as an immediate-release (IR) tablet and syrup. An orally disintegrating tablet (ODT) dosage form would be advantageous for patients who experience difficulty in swallowing large tablets or capsules or those who experience dysphagia. Controlled-release (CR) capsule and ODT formulations containing melperone HCl were developed with target in vitro release profiles suitable for a once-daily dosing regimen. Both dosage forms allow for the convenient production of dose-proportional multiple strengths. Two ODT formulations exhibiting fast and medium release profiles and one medium release profile capsule formulation (each 50 mg) were tested in vivo using IR syrup as the reference. The two medium release formulations were shown to be bioequivalent to each other and are suitable for once-daily dosing. Based on the analytical and organoleptic test results, as well as the blend uniformity and in-process compression data at various compression forces using coated beads produced at one-tenth (1/10) commercial scale, both formulations in the form of CR capsules and CR ODTs have shown suitability for progression into further clinical development. PMID:22356215

  1. Bockron as a Medium of Learning in The Process of Inquiry based Learning to Improve Science Process Skills of Junior High School Students in Growth and Development Concept

    NASA Astrophysics Data System (ADS)

    Mayasari, D.

    2017-02-01

    Investigative research on Influence of bockron as a medium of learning in process of inquiry-based learning to the development of science process skills on the concept of growth and development. This research was done in an effort to follow up underdeveloped skills of observing, communicating andconclude on students. This research was conducted using classroom action research (PTK), which consisted of 3 cycles. Cycle 1 students observe differences in growth and development, cycle 2 students measure the growth rate, cycle 3 students observe factors that influence growth and development, In these three cycles is used as a planting medium bocron (bottles and dacron). It involves 8th grade junior high-school students of 14-15 years old as research subjects in six meetings. Indicators of process skill include observation, communication, interpretation and inference. Data is collected through students’ work sheets, written tests and observation. Processing of the data to see N-Gain used Microsoft Excel 2007, and the results showed that an increase in science process skills with a value of medium N-Gain (0,63). Bokron learning medium easily and cheaply obtainable around the students, particularly those in urban areas is quite difficult to get land to be used as aplanting medium. In addition to observation of growth and development, bokron media can also be used to observe the motion in plants. The use bokron as a learning medium can train and develop science process skills, attitude and scientific method also gives students concrete experience of the process of growth and development in plants.

  2. Pre-Pregnancy Body Mass Index, Gestational Weight Gain, and Birth Weight: A Cohort Study in China.

    PubMed

    Yang, Shaoping; Peng, Anna; Wei, Sheng; Wu, Jing; Zhao, Jinzhu; Zhang, Yiming; Wang, Jing; Lu, Yuan; Yu, Yuzhen; Zhang, Bin

    2015-01-01

    To assess whether pre-pregnancy body mass index (BMI) modify the relationship between gestational weight gain (GWG) and child birth weight (specifically, presence or absence of low birth weight (LBW) or presence of absence of macrosomia), and estimates of the relative risk of macrosomia and LBW based on pre-pregnancy BMI were controlled in Wuhan, China. From June 30, 2011 to June 30, 2013. All data was collected and available from the perinatal health care system. Logistic regression models were used to estimate the independent association among pregnancy weight gain, LBW, normal birth weight, and macrosomia within different pre-pregnancy BMI groups. We built different logistic models for the 2009 Institute of Medicine (IOM) Guidelines and Chinese-recommended GWG which was made from this sample. The Chinese-recommended GWG was derived from the quartile values (25th-75th percentiles) of weight gain at the time of delivery in the subjects which comprised our sample. For LBW children, using the recommended weight gain of the IOM and Chinese women as a reference, the OR for a pregnancy weight gain below recommendations resulted in a positive relationship for lean and normal weight women, but not for overweight and obese women. For macrosomia, considering the IOM's recommended weight gain as a reference, the OR magnitude for pregnancy weight gain above recommendations resulted in a positive correlation for all women. The OR for a pregnancy weight gain below recommendations resulted in a negative relationship for normal BMI and lean women, but not for overweight and obese women based on the IOM recommendations, significant based on the recommended pregnancy weight gain for Chinese women. Of normal weight children, 56.6% were above the GWG based on IOM recommendations, but 26.97% of normal weight children were above the GWG based on Chinese recommendations. A GWG above IOM recommendations might not be helpful for Chinese women. We need unified criteria to classify adult

  3. Pre-Pregnancy Body Mass Index, Gestational Weight Gain, and Birth Weight: A Cohort Study in China

    PubMed Central

    Wei, Sheng; Wu, Jing; Zhao, Jinzhu; Zhang, Yiming; Wang, Jing; Lu, Yuan; Yu, Yuzhen; Zhang, Bin

    2015-01-01

    Objective To assess whether pre-pregnancy body mass index (BMI) modify the relationship between gestational weight gain (GWG) and child birth weight (specifically, presence or absence of low birth weight (LBW) or presence of absence of macrosomia), and estimates of the relative risk of macrosomia and LBW based on pre-pregnancy BMI were controlled in Wuhan, China. Methods From June 30, 2011 to June 30, 2013. All data was collected and available from the perinatal health care system. Logistic regression models were used to estimate the independent association among pregnancy weight gain, LBW, normal birth weight, and macrosomia within different pre-pregnancy BMI groups. We built different logistic models for the 2009 Institute of Medicine (IOM) Guidelines and Chinese-recommended GWG which was made from this sample. The Chinese-recommended GWG was derived from the quartile values (25th-75th percentiles) of weight gain at the time of delivery in the subjects which comprised our sample. Results For LBW children, using the recommended weight gain of the IOM and Chinese women as a reference, the OR for a pregnancy weight gain below recommendations resulted in a positive relationship for lean and normal weight women, but not for overweight and obese women. For macrosomia, considering the IOM’s recommended weight gain as a reference, the OR magnitude for pregnancy weight gain above recommendations resulted in a positive correlation for all women. The OR for a pregnancy weight gain below recommendations resulted in a negative relationship for normal BMI and lean women, but not for overweight and obese women based on the IOM recommendations, significant based on the recommended pregnancy weight gain for Chinese women. Of normal weight children, 56.6% were above the GWG based on IOM recommendations, but 26.97% of normal weight children were above the GWG based on Chinese recommendations. Conclusions A GWG above IOM recommendations might not be helpful for Chinese women. We

  4. Job Stress in the United Kingdom: Are Small and Medium-Sized Enterprises and Large Enterprises Different?

    PubMed

    Lai, Yanqing; Saridakis, George; Blackburn, Robert

    2015-08-01

    This paper examines the relationships between firm size and employees' experience of work stress. We used a matched employer-employee dataset (Workplace Employment Relations Survey 2011) that comprises of 7182 employees from 1210 private organizations in the United Kingdom. Initially, we find that employees in small and medium-sized enterprises experience lower level of overall job stress than those in large enterprises, although the effect disappears when we control for individual and organizational characteristics in the model. We also find that quantitative work overload, job insecurity and poor promotion opportunities, good work relationships and poor communication are strongly associated with job stress in the small and medium-sized enterprises, whereas qualitative work overload, poor job autonomy and employee engagements are more related with larger enterprises. Hence, our estimates show that the association and magnitude of estimated effects differ significantly by enterprise size. Copyright © 2013 John Wiley & Sons, Ltd.

  5. Invention and Gain Analysis.

    ERIC Educational Resources Information Center

    Weber, Robert J.; Dixon, Stacey

    1989-01-01

    Gain analysis is applied to the invention of the sewing needle as well as different sewing implements and modes of sewing. The analysis includes a two-subject experiment. To validate the generality of gain heuristics and underlying switching processes, the invention of the assembly line is also analyzed. (TJH)

  6. Optical devices and methods employing nanoparticles, microcavities, and semicontinuous metal films

    NASA Technical Reports Server (NTRS)

    Shalaev, Vladimir M. (Inventor); Sarychev, Andrey K. (Inventor); Armstrong, Robert L. (Inventor); Smith, Harold V. (Inventor); Ying, Z. Charles (Inventor)

    2006-01-01

    An optical sensing enhancing material (and corresponding method of making) comprising: a medium, the medium comprising a plurality of aggregated nanoparticles comprising fractals; and a microcavity, wherein the medium is located in a vicinity of the microcavity. Also an optical sensor and sensing method comprising: providing a doped medium, the medium comprising a plurality of aggregated nanoparticles comprising fractals, with the material; locating the doped medium in the vicinity of a microcavity; exciting the doped medium with a light source; and detecting light reflected from the doped medium. Also an optical sensing enhancing material comprising a medium, the medium comprising a semicontinuous metal film of randomly distributed metal particles and their clusters at approximately their percolation threshold. The medium preferably additionally comprises a microcavity/microresonator. Also devices and methods employing such material.

  7. Measurements of the Low Frequency Gain Fluctuations of a 30 GHz High-Electron-Mobility-Transistor Cryogenic Amplifier

    NASA Technical Reports Server (NTRS)

    Jarosik, Norman

    1994-01-01

    Low frequency gain fluctuations of a 30 GHz cryogenic HEMT amplifier have been measured with the input of the amplifier connected to a 15 K load. Effects of fluctuations of other components of the test set-up were eliminated by use of a power-power correlation technique. Strong correlation between output power fluctuations of the amplifier and drain current fluctuations of the transistors comprising the amplifier are observed. The existence of these correlations introduces the possibility of regressing some of the excess noise from the HEMT amplifier's output using the measured drain currents.

  8. An Enhanced Linkage Map of the Sheep Genome Comprising More Than 1000 Loci

    PubMed Central

    Maddox, Jillian F.; Davies, Kizanne P.; Crawford, Allan M.; Hulme, Dennis J.; Vaiman, Daniel; Cribiu, Edmond P.; Freking, Bradley A.; Beh, Ken J.; Cockett, Noelle E.; Kang, Nina; Riffkin, Christopher D.; Drinkwater, Roger; Moore, Stephen S.; Dodds, Ken G.; Lumsden, Joanne M.; van Stijn, Tracey C.; Phua, Sin H.; Adelson, David L.; Burkin, Heather R.; Broom, Judith E.; Buitkamp, Johannes; Cambridge, Lisa; Cushwa, William T.; Gerard, Emily; Galloway, Susan M.; Harrison, Blair; Hawken, Rachel J.; Hiendleder, Stefan; Henry, Hannah M.; Medrano, Juan F.; Paterson, Korena A.; Schibler, Laurent; Stone, Roger T.; van Hest, Beryl

    2001-01-01

    A medium-density linkage map of the ovine genome has been developed. Marker data for 550 new loci were generated and merged with the previous sheep linkage map. The new map comprises 1093 markers representing 1062 unique loci (941 anonymous loci, 121 genes) and spans 3500 cM (sex-averaged) for the autosomes and 132 cM (female) on the X chromosome. There is an average spacing of 3.4 cM between autosomal loci and 8.3 cM between highly polymorphic [polymorphic information content (PIC) ≥ 0.7] autosomal loci. The largest gap between markers is 32.5 cM, and the number of gaps of >20 cM between loci, or regions where loci are missing from chromosome ends, has been reduced from 40 in the previous map to 6. Five hundred and seventy-three of the loci can be ordered on a framework map with odds of >1000 : 1. The sheep linkage map contains strong links to both the cattle and goat maps. Five hundred and seventy-two of the loci positioned on the sheep linkage map have also been mapped by linkage analysis in cattle, and 209 of the loci mapped on the sheep linkage map have also been placed on the goat linkage map. Inspection of ruminant linkage maps indicates that the genomic coverage by the current sheep linkage map is comparable to that of the available cattle maps. The sheep map provides a valuable resource to the international sheep, cattle, and goat gene mapping community. PMID:11435411

  9. An amorphous alloy core medium frequency magnetic-link for medium voltage photovoltaic inverters

    NASA Astrophysics Data System (ADS)

    Rabiul Islam, Md.; Guo, Youguang; Wei Lin, Zhi; Zhu, Jianguo

    2014-05-01

    The advanced magnetic materials with high saturation flux density and low specific core loss have led to the development of an efficient, compact, and lightweight multiple-input multiple-output medium frequency magnetic-link. It offers a new route to eliminate some critical limitations of recently proposed medium voltage photovoltaic inverters. In this paper, a medium frequency magnetic-link is developed with Metglas amorphous alloy 2605S3A. The common magnetic-link generates isolated and balanced multiple DC supplies for all of the H-bridge inverter cells of the medium voltage inverter. The design and implementation of the prototype, test platform, and the experimental test results are analyzed and discussed. The medium frequency non-sinusoidal excitation electromagnetic characteristics of alloy 2605S3A are also compared with that of alloy 2605SA1. It is expected that the proposed new technology will have great potential for future renewable power generation systems and smart grid applications.

  10. Loop gain stabilizing with an all-digital automatic-gain-control method for high-precision fiber-optic gyroscope.

    PubMed

    Zheng, Yue; Zhang, Chunxi; Li, Lijing; Song, Lailiang; Chen, Wen

    2016-06-10

    For a fiber-optic gyroscope (FOG) using electronic dithers to suppress the dead zone, without a fixed loop gain, the deterministic compensation for the dither signals in the control loop of the FOG cannot remain accurate, resulting in the dither residuals in the FOG rotation rate output and the navigation errors in the inertial navigation system. An all-digital automatic-gain-control method for stabilizing the loop gain of the FOG is proposed. By using a perturbation square wave to measure the loop gain of the FOG and adding an automatic gain control loop in the conventional control loop of the FOG, we successfully obtain the actual loop gain and make the loop gain converge to the reference value. The experimental results show that in the case of 20% variation in the loop gain, the dither residuals are successfully eliminated and the standard deviation of the FOG sampling outputs is decreased from 2.00  deg/h to 0.62  deg/h (sampling period 2.5 ms, 10 points smoothing). With this method, the loop gain of the FOG can be stabilized over the operation temperature range and in the long-time application, which provides a solid foundation for the engineering applications of the high-precision FOG.

  11. Weight gain following treatment of hyperthyroidism.

    PubMed

    Dale, J; Daykin, J; Holder, R; Sheppard, M C; Franklyn, J A

    2001-08-01

    Patients frequently express concern that treating hyperthyroidism will lead to excessive weight gain. This study aimed to determine the extent of, and risk factors for, weight gain in an unselected group of hyperthyroid patients. We investigated 162 consecutive hyperthyroid patients followed for at least 6 months. Height, weight, clinical features, biochemistry and management were recorded at each clinic visit. Documented weight gain was 5.42 +/- 0.46 kg (mean +/- SE) and increase in BMI was 8.49 +/- 0.71%, over a mean 24.2 +/- 1.6 months. Pre-existing obesity, Graves' disease causing hyperthyroidism, weight loss before presentation and length of follow-up each independently predicted weight gain. Patients treated with thionamides or radioiodine gained a similar amount of weight (thionamides, n = 87, 5.16 +/- 0.63 kg vs. radioiodine, n = 62, 4.75 +/- 0.57 kg, P = 0.645), but patients who underwent thyroidectomy (n = 13) gained more weight (10.27 +/- 2.56 kg vs. others, P = 0.007). Development of hypothyroidism (even transiently) was associated with weight gain (never hypothyroid, n = 102, 4.57 +/- 0.52 kg, transiently hypothyroid, n = 29, 5.37 +/- 0.85 kg, on T4, n = 31, 8.06 +/- 1.42 kg, P = 0.014). This difference remained after correcting for length of follow-up. In the whole cohort, weight increased by 3.95 +/- 0.40 kg at 1 year (n = 144) to 9.91 +/- 1.62 kg after 4 years (n = 27) (P = 0.008), representing a mean weight gain of 3.66 +/- 0.44 kg/year. We have demonstrated marked weight gain after treatment of hyperthyroidism. Pre-existing obesity, a diagnosis of Graves' disease and prior weight loss independently predicted weight gain and weight continued to rise with time. Patients who became hypothyroid, despite T4 replacement, gained most weight.

  12. Study of gain-coupled distributed feedback laser based on high order surface gain-coupled gratings

    NASA Astrophysics Data System (ADS)

    Gao, Feng; Qin, Li; Chen, Yongyi; Jia, Peng; Chen, Chao; Cheng, LiWen; Chen, Hong; Liang, Lei; Zeng, Yugang; Zhang, Xing; Wu, Hao; Ning, Yongqiang; Wang, Lijun

    2018-03-01

    Single-longitudinal-mode, gain-coupled distributed feedback (DFB) lasers based on high order surface gain-coupled gratings are achieved. Periodic surface metal p-contacts with insulated grooves realize gain-coupled mechanism. To enhance gain contrast in the quantum wells without the introduction of effective index-coupled effect, groove length and depth were well designed. Our devices provided a single longitudinal mode with the maximum CW output power up to 48.8 mW/facet at 971.31 nm at 250 mA without facet coating, 3dB linewidth (<3.2 pm) and SMSR (>39 dB). Optical bistable characteristic was observed with a threshold current difference. Experimentally, devices with different cavity lengths were contrasted on power-current and spectrum characteristics. Due to easy fabrication technique and stable performance, it provides a method of fabricating practical gain-coupled distributed feedback lasers for commercial applications.

  13. Immunogenic compositions comprising human immunodeficiency virus (HIV) mosaic Nef proteins

    DOEpatents

    Korber, Bette T [Los Alamos, NM; Perkins, Simon [Los Alamos, NM; Bhattacharya, Tanmoy [Los Alamos, NM; Fischer, William M [Los Alamos, NM; Theiler, James [Los Alamos, NM; Letvin, Norman [Boston, MA; Haynes, Barton F [Durham, NC; Hahn, Beatrice H [Birmingham, AL; Yusim, Karina [Los Alamos, NM; Kuiken, Carla [Los Alamos, NM

    2012-02-21

    The present invention relates to mosaic clade M HIV-1 Nef polypeptides and to compositions comprising same. The polypeptides of the invention are suitable for use in inducing an immune response to HIV-1 in a human.

  14. 7. Detail view of reinforced concrete archrings comprising dam's upstream ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Detail view of reinforced concrete arch-rings comprising dam's upstream face. Impressions of the wooden formwork used in construction are visible in the concrete. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  15. Loss and gain of cone types in vertebrate ciliary photoreceptor evolution.

    PubMed

    Musser, Jacob M; Arendt, Detlev

    2017-11-01

    Ciliary photoreceptors are a diverse cell type family that comprises the rods and cones of the retina and other related cell types such as pineal photoreceptors. Ciliary photoreceptor evolution has been dynamic during vertebrate evolution with numerous gains and losses of opsin and phototransduction genes, and changes in their expression. For example, early mammals lost all but two cone opsins, indicating loss of cone receptor types in response to nocturnal lifestyle. Our review focuses on the comparison of specifying transcription factors and cell type-specific transcriptome data in vertebrate retinae to build and test hypotheses on ciliary photoreceptor evolution. Regarding cones, recent data reveal that a combination of factors specific for long-wavelength sensitive opsin (Lws)- cones in non-mammalian vertebrates (Thrb and Rxrg) is found across all differentiating cone photoreceptors in mice. This suggests that mammalian ancestors lost all but one ancestral cone type, the Lws-cone. We test this hypothesis by a correlation analysis of cone transcriptomes in mouse and chick, and find that, indeed, transcriptomes of all mouse cones are most highly correlated to avian Lws-cones. These findings underscore the importance of specifying transcription factors in tracking cell type evolution, and shed new light on the mechanisms of cell type loss and gain in retina evolution. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  16. Metal-air cell comprising an electrolyte with a room temperature ionic liquid and hygroscopic additive

    DOEpatents

    Friesen, Cody A.; Krishnan, Ramkumar; Tang, Toni; Wolfe, Derek

    2014-08-19

    An electrochemical cell comprising an electrolyte comprising water and a hydrophobic ionic liquid comprising positive ions and negative ions. The electrochemical cell also includes an air electrode configured to absorb and reduce oxygen. A hydrophilic or hygroscopic additive modulates the hydrophobicity of the ionic liquid to maintain a concentration of the water in the electrolyte is between 0.001 mol % and 25 mol %.

  17. Effect of the solution temperature in a singlet-oxygen generator on the formation of active medium in an ejector oxygen - iodine laser

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zagidullin, M V; Nikolaev, V D; Svistun, M I

    2002-02-28

    The influence of the solution temperature in a singlet-oxygen generator on the formation of the active medium in the ejector oxygen - iodine laser is investigated. The following parameters of the active medium at the solution temperature -20{sup 0}C are obtained: the gain is 7.2 x 10{sup -3} cm{sup -1}, the Mach number is M=2, the temperature is 205 K, and the static pressure is 9.3 mmHg. As the solution temperature is increased to -4{sup 0}C, the gain decreases to 5 x 10{sup 3} cm{sup -1}, the Mach number decreases to 1.78, while the temperature and the static pressure increasemore » to 241 K and 10.7 mmHg, respectively. As the solution temperature increases from -20 to -4{sup 0}C, the losses in O{sub 2}({sup 1}{Delta}) increase by less than 20%, while the dissociation efficiency of molecular iodine decreases by less than 21%. (lasers, active media)« less

  18. Optimization of control gain by operator adjustment

    NASA Technical Reports Server (NTRS)

    Kruse, W.; Rothbauer, G.

    1973-01-01

    An optimal gain was established by measuring errors at 5 discrete control gain settings in an experimental set-up consisting of a 2-dimensional, first-order pursuit tracking task performed by subjects (S's). No significant experience effect on optimum gain setting was found in the first experiment. During the second experiment, in which control gain was continuously adjustable, high experienced S's tended to reach the previously determined optimum gain quite accurately and quickly. Less experienced S's tended to select a marginally optimum gain either below or above the experimentally determined optimum depending on initial control gain setting, although mean settings of both groups were equal. This quick and simple method is recommended for selecting control gains for different control systems and forcing functions.

  19. Downhole geothermal well sensors comprising a hydrogen-resistant optical fiber

    DOEpatents

    Weiss, Jonathan D.

    2005-02-08

    A new class of optical fiber based thermal sensors has been invented. The new sensors comprise hydrogen-resistant optical fibers which are able to withstand a hot, hydrogen-containing environment as is often found in the downhole well environment.

  20. Optical antenna gain. I - Transmitting antennas

    NASA Technical Reports Server (NTRS)

    Klein, B. J.; Degnan, J. J.

    1974-01-01

    The gain of centrally obscured optical transmitting antennas is analyzed in detail. The calculations, resulting in near- and far-field antenna gain patterns, assume a circular antenna illuminated by a laser operating in the TEM-00 mode. A simple polynomial equation is derived for matching the incident source distribution to a general antenna configuration for maximum on-axis gain. An interpretation of the resultant gain curves allows a number of auxiliary design curves to be drawn that display the losses in antenna gain due to pointing errors and the cone angle of the beam in the far field as a function of antenna aperture size and its central obscuration. The results are presented in a series of graphs that allow the rapid and accurate evaluation of the antenna gain which may then be substituted into the conventional range equation.

  1. Viscous lubricant composition comprising mixed esters and a silicone oil

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ayres, P.J.

    1981-03-03

    A viscous composition capable of substantially retaining its viscosity within a temperature range of from 5*-30* C. Comprising as its components diisopropyl adipate, a mixture of cetyl and stearyl octanoates, glyceryl tribehenate, silicone oil and a surfactant is described.

  2. Behavioral Treatment for Weight Gain Prevention Among Black Women in Primary Care Practice

    PubMed Central

    Bennett, Gary G.; Foley, Perry; Levine, Erica; Whiteley, Jessica; Askew, Sandy; Steinberg, Dori M.; Batch, Bryan; Greaney, Mary L.; Miranda, Heather; Wroth, Thomas H.; Holder, Marni Gwyther; Emmons, Karen M.; Puleo, Elaine

    2014-01-01

    IMPORTANCE Few weight loss treatments produce clinically meaningful weight loss outcomes among black women, particularly in the primary care setting. New weight management strategies are necessary for this population. Weight gain prevention might be an effective treatment option, with particular benefits for overweight and class 1 obese black women. OBJECTIVE To compare changes in weight and cardiometabolic risk during a 12-month period among black women randomized to a primary care–based behavioral weight gain prevention intervention, relative to usual care. DESIGN, SETTING, AND PARTICIPANTS Two-arm randomized clinical trial (the Shape Program). We recruited patients from a 6-site community health center system. We randomized 194 overweight and class 1 obese (body mass index [calculated as weight in kilograms divided by height in meters squared], 25–34.9) premenopausal black women aged 25 to 44 years. Enrollment began on December 7, 2009; 12- and 18-month assessments were completed in February and October 2, 2012. INTERVENTIONS The medium-intensity intervention included tailored behavior change goals, weekly self-monitoring via interactive voice response, monthly counseling calls, tailored skills training materials, and a gym membership. MAIN OUTCOMES AND MEASURES Twelve-month change in weight and body mass index and maintenance of change at 18 months. RESULTS Participants had a mean age of 35.4 years, a mean weight of 81.1 kg, and a mean body mass index of 30.2 at baseline. Most were socioeconomically disadvantaged (79.7% with educational level less than a college degree; 74.3% reporting annual income <$30 000). The 12-month weight change was larger among intervention participants (mean [SD], −1.0 [0.5] kg), relative to usual care (0.5 [0.5] kg; mean difference, −1.4 kg [95%CI, −2.8 to −0.1 kg]; P = .04). At month 12, 62% of intervention participants were at or below their baseline weights compared with 45% of usual-care participants (P = .03). By 18

  3. Spatial solitons of desired intensity and width and their self-tapering/uptapering in cubic quintic nonlinear medium

    NASA Astrophysics Data System (ADS)

    Krishna Sarkar, Ram; Medhekar, S.

    2007-12-01

    In this paper, we have investigated the propagation behavior of a Gaussian beam in cubic quintic nonlinear medium with and without absorption or gain. A governing differential equation for the evolution of beam width with the distance of propagation has been derived using the standard parabolic equation approach. By solving the governing equation numerically for different sets of parameters, we have shown that spatial solitons of fixed width and desired intensity and of fixed intensity and desired width are possible. Such liberty does not exist in other saturable media. We have also investigated self-tapering and self-uptapering of spatial solitons in the presence of absorption or gain and showed that the rate of self-tapering/uptapering is not only controlled by the magnitude of absorption or gain but also by the values of cubic and quintic terms. It is revealed that by self-tapering, the smallest achievable soliton width decreases/increases by increasing the magnitude of the cubic/quintic term. It is also revealed that the smallest achievable soliton width by self-tapering, is smaller for a larger initial width.

  4. Chemically defined medium and Caenorhabditis elegans

    NASA Technical Reports Server (NTRS)

    Szewczyk, Nathaniel J.; Kozak, Elena; Conley, Catharine A.

    2003-01-01

    BACKGROUND: C. elegans has been established as a powerful genetic system. Use of a chemically defined medium (C. elegans Maintenance Medium (CeMM)) now allows standardization and systematic manipulation of the nutrients that animals receive. Liquid cultivation allows automated culturing and experimentation and should be of use in large-scale growth and screening of animals. RESULTS: We find that CeMM is versatile and culturing is simple. CeMM can be used in a solid or liquid state, it can be stored unused for at least a year, unattended actively growing cultures may be maintained longer than with standard techniques, and standard C. elegans protocols work well with animals grown in defined medium. We also find that there are caveats to using defined medium. Animals in defined medium grow more slowly than on standard medium, appear to display adaptation to the defined medium, and display altered growth rates as they change the composition of the defined medium. CONCLUSIONS: As was suggested with the introduction of C. elegans as a potential genetic system, use of defined medium with C. elegans should prove a powerful tool.

  5. Personalized Health Planning With Integrative Health Coaching to Reduce Obesity Risk Among Women Gaining Excess Weight During Pregnancy

    PubMed Central

    Yang, Nancy Y.; Wroth, Shelley; Parham, Catherine; Strait, Melva

    2013-01-01

    Health coaching is an emerging behavioral intervention to improve outcomes in chronic disease management and prevention; however, no studies have investigated its utility in postpartum women who have gained excess weight during pregnancy. A 32-year-old primigravida woman who was overweight at conception and gained 23 lbs more than Institute of Medicine recommendations for her pre-pregnancy body mass index participated in a 6-month personalized health planning with integrative health coaching (PHPIHC) intervention. The intervention included a baseline health risk assessment review with a healthcare provider and eight biweekly, 30-minute telephonic health coaching sessions. The participant demonstrated improvement in physical activity, energy expenditure, knowledge, and confidence to engage in healthpromoting behaviors. Although the participant did not reach the target weight by completion of the health coaching sessions, follow up 8 months later indicated she achieved the target goal (within 5% of prepregnancy weight). This case report suggests that PHP-IHC can support postpartum women in returning to pre-pregnancy weight after gaining excess gestational weight. Future research and clinical trials are needed to determine the best timing, length, and medium (online, in-person, telephonic) of PHP-IHC for postpartum women. PMID:24278848

  6. Recyclable organic solar cells on substrates comprising cellulose nanocrystals (CNC)

    DOEpatents

    Kippelen, Bernard; Fuentes-Hernandez, Canek; Zhou, Yinhua; Moon, Robert; Youngblood, Jeffrey P

    2015-12-01

    Recyclable organic solar cells are disclosed herein. Systems and methods are further disclosed for producing, improving performance, and for recycling the solar cells. In certain example embodiments, the recyclable organic solar cells disclosed herein include: a first electrode; a second electrode; a photoactive layer disposed between the first electrode and the second electrode; an interlayer comprising a Lewis basic oligomer or polymer disposed between the photoactive layer and at least a portion of the first electrode or the second electrode; and a substrate disposed adjacent to the first electrode or the second electrode. The interlayer reduces the work function associated with the first or second electrode. In certain example embodiments, the substrate comprises cellulose nanocrystals that can be recycled. In certain example embodiments, one or more of the first electrode, the photoactive layer, and the second electrode may be applied by a film transfer lamination method.

  7. Understanding Supply Chain Management Practices for Small and Medium-Sized Enterprises

    NASA Astrophysics Data System (ADS)

    Thoo, AC; Sulaiman, Z.; Choi, SL; Kohar, UHA

    2017-06-01

    Small and medium enterprises (SMEs) are a major source of dynamism, innovation and flexibility for emerging and developing countries, as well as for the economies of the most industrialised nations. However, the survival and growth of SMEs can be difficult in the current competitive business environment and global marketplace. It can be a real challenge to deliver the right product and service at the most opportune time and at the lowest possible cost to the right customer. The challenge stresses the importance of managing cross-boundary relationships between business partners. For gaining a competitive advantage, supply chain management (SCM) is an effective tool to SMEs. Therefore, this paper aims to review the tenet of SCM, its benefits and practices to SMEs.

  8. Building the Hot Intra-Group Medium in Spiral-Rich Compact Groups

    NASA Astrophysics Data System (ADS)

    O'Sullivan, Ewan

    2014-11-01

    Galaxy groups provide a natural laboratory for investigating the formation of the hot intergalactic medium (IGM). While galaxy clusters gain most of their hot gas through accretion and gravitational shocks, in groups the processes of galaxy evolution (stripping, collisions, star formation) play an important role in the initial build up of the hot halo. We present Chandra and XMM-Newton observations of groups still in the process of forming their IGM, including the well known compact groups HCG 16 and Stephan's Quintet (HCG 92). We show that starburst winds and shock-heating of stripped HI provide important contributions of gas and metals to the IGM, and discuss the impact of gas stripping, enhanced star formation and nuclear activity in the group member galaxies.

  9. Optical antenna gain. III - The effect of secondary element support struts on transmitter gain

    NASA Technical Reports Server (NTRS)

    Klein, B. J.; Degnan, J. J.

    1976-01-01

    The effect of a secondary-element spider support structure on optical antenna transmitter gain is analyzed. An expression describing the influence of the struts on the axial gain, in both the near and far fields, is derived as a function of the number of struts and their width. It is found that, for typical systems, the struts degrade the on-axis gain by less than 0.4 dB, and the first side-lobe level is not increased significantly. Contour plots have also been included to show the symmetry of the far-field distributions for three- and four-support members.

  10. High-gain magnetized inertial fusion.

    PubMed

    Slutz, Stephen A; Vesey, Roger A

    2012-01-13

    Magnetized inertial fusion (MIF) could substantially ease the difficulty of reaching plasma conditions required for significant fusion yields, but it has been widely accepted that the gain is not sufficient for fusion energy. Numerical simulations are presented showing that high-gain MIF is possible in cylindrical liner implosions based on the MagLIF concept [S. A. Slutz et al Phys. Plasmas 17, 056303 (2010)] with the addition of a cryogenic layer of deuterium-tritium (DT). These simulations show that a burn wave propagates radially from the magnetized hot spot into the surrounding much denser cold DT given sufficient hot-spot areal density. For a drive current of 60 MA the simulated gain exceeds 100, which is more than adequate for fusion energy applications. The simulated gain exceeds 1000 for a drive current of 70 MA.

  11. Design, fabrication, and optimization of quantum cascade laser cavities and spectroscopy of the intersubband gain

    NASA Astrophysics Data System (ADS)

    Dirisu, Afusat Olayinka

    Quantum Cascade (QC) lasers are intersubband light sources operating in the wavelength range of ˜ 3 to 300 mum and are used in applications such as sensing (environmental, biological, and hazardous chemical), infrared countermeasures, and free-space infrared communications. The mid-infrared range (i.e. lambda ˜ 3-30 mum) is of particular importance in sensing because of the strong interaction of laser radiation with various chemical species, while in free space communications the atmospheric windows of 3-5 mum and 8-12 mum are highly desirable for low loss transmission. Some of the requirements of these applications include, (1) high output power for improved sensitivity; (2) high operating temperatures for compact and cost-effective systems; (3) wide tunability; (4) single mode operation for high selectivity. In the past, available mid-infrared sources, such as the lead-salt and solid-state lasers, were bulky, expensive, or emit low output power. In recent years, QC lasers have been explored as cost-effective and compact sources because of their potential to satisfy and exceed all the above requirements. Also, the ultrafast carrier lifetimes of intersubband transitions in QC lasers are promising for high bandwidth free-space infrared communication. This thesis was focused on the improvement of QC lasers through the design and optimization of the laser cavity and characterization of the laser gain medium. The optimization of the laser cavity included, (1) the design and fabrication of high reflection Bragg gratings and subwavelength antireflection gratings, by focused ion beam milling, to achieve tunable, single mode and high power QC lasers, and (2) modeling of slab-coupled optical waveguide QC lasers for high brightness output beams. The characterization of the QC laser gain medium was carried out using the single-pass transmission experiment, a sensitive measurement technique, for probing the intersubband transitions and the electron distribution of QC lasers

  12. Ethanol production using a soy hydrolysate-based medium or a yeast autolysate-based medium

    DOEpatents

    Ingram, Lonnie O.

    2000-01-01

    This invention presents a method for the production of ethanol that utilizes a soy hydrolysate-based nutrient medium or a yeast autolysate-based medium nutrient medium in conjunction with ethanologenic bacteria and a fermentable sugar for the cost-effective production of ethanol from lignocellulosic biomass. The invention offers several advantages over presently available media for use in ethanol production, including consistent quality, lack of toxins and wide availability.

  13. The relative persuasiveness of gain-framed versus loss-Framed HIV testing message: evidence from a field experiment in northwest Ethiopia.

    PubMed

    Bekalu, Mesfin Awoke; Eggermont, Steven

    2014-01-01

    This study assessed the relative advantages of gain- versus loss-framed messages for promoting HIV testing among a sample of urban and rural residents in northwest Ethiopia. The authors randomly assigned 394 participants to read gain-framed (n = 196) or loss-framed (n = 198) HIV testing message prepared in a form of brochure. Experience with HIV testing, concern about and information needs on HIV/AIDS, and urbanity versus rurality significantly moderated the effects of framing on intention to test for HIV. A gain-frame advantage was found among urbanites, participants with high experience with HIV testing, and those with high concern about and information needs on HIV/AIDS, suggesting a more likely construal of HIV testing as a prevention behavior among these individuals. In contrast, a loss-frame advantage was found among ruralites and participants with low concern about and information needs on HIV/AIDS, suggesting a more likely construal of HIV testing as a detection behavior among such individuals. Moreover, gain- and loss-framing led to similar outcomes among individuals with low levels of experience with HIV testing, with a slight advantage for the loss-framed message. All of the framing effects obtained were of small to medium size.

  14. Determination of the STIS CCD Gain

    NASA Astrophysics Data System (ADS)

    Riley, Allyssa; Monroe, TalaWanda; Lockwood, Sean

    2016-09-01

    This report summarizes the analysis and absolute gain results of the STIS Cycle 23 special calibration program 14424 that was designed to measure the gain of amplifiers A, C and D at nominal gain settings of 1 and 4 e-/DN. We used the mean-variance technique and the results indicate a <3.5% change in the gain for amplifier D from when it was originally calculated pre-flight. We compared these values to previous measurements from Cycles 17 through 23. This report outlines the observations, methodology, and results of the mean-variance technique.

  15. Measurement of Antenna Bore-Sight Gain

    NASA Technical Reports Server (NTRS)

    Fortinberry, Jarrod; Shumpert, Thomas

    2016-01-01

    The absolute or free-field gain of a simple antenna can be approximated using standard antenna theory formulae or for a more accurate prediction, numerical methods may be employed to solve for antenna parameters including gain. Both of these methods will result in relatively reasonable estimates but in practice antenna gain is usually verified and documented via measurements and calibration. In this paper, a relatively simple and low-cost, yet effective means of determining the bore-sight free-field gain of a VHF/UHF antenna is proposed by using the Brewster angle relationship.

  16. IQ Gains and the Binet Decrements.

    ERIC Educational Resources Information Center

    Flynn, James R.

    1984-01-01

    Thorndike's Stanford-Binet data suggest that from 1932 to 1971-72 preschool children enjoyed greater IQ gains than older children, possibly due to the rise of television. Additional analysis indicated that gains were either due to sampling error or totally antedated 1947. Gains of 12 IQ points were found for Americans. (Author/EGS)

  17. An adaptive supramolecular hydrogel comprising self-sorting double nanofibre networks

    NASA Astrophysics Data System (ADS)

    Shigemitsu, Hajime; Fujisaku, Takahiro; Tanaka, Wataru; Kubota, Ryou; Minami, Saori; Urayama, Kenji; Hamachi, Itaru

    2018-02-01

    Novel soft materials should comprise multiple supramolecular nanostructures whose responses (for example, assembly and disassembly) to external stimuli can be controlled independently. Such multicomponent systems are present in living cells and control the formation and break-up of a variety of supramolecular assemblies made of proteins, lipids, DNA and RNA in response to external stimuli; however, artificial counterparts are challenging to make. Here, we present a hybrid hydrogel consisting of a self-sorting double network of nanofibres in which each network responds to an applied external stimulus independent of the other. The hydrogel can be made to change its mechanical properties and rates of release of encapsulated proteins by adding Na2S2O4 or bacterial alkaline phosphatase. Notably, the properties of the gel depend on the order in which the external stimuli are applied. Multicomponent hydrogels comprising orthogonal stimulus-responsive supramolecular assemblies would be suitable for designing novel adaptive materials.

  18. Switchable Ionic Liquids: An Environmentally Friendly Medium to Synthesise Nanoparticulate Green Rust

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lao, David; Kukkadapu, Ravi; Kovarik, Libor

    Under anoxic conditions, a novel nanoparticulate green rust with carbonate (nano GR) was synthesized by addition of methanol to degassed switchable ionic liquid (SWIL) solution comprised of 1-hexanol, diazabicycloundec-7-ene (DBU), CO2 and Fe(C2H3O2)2 (Fe(OAc)2). Variable temperature Mössbauer spectroscopy studies indicated the product to be predominantly GR while TEM-SAED method confirmed it be nanoparticulate in nature. Experiments with and without methanol in the SWIL medium suggest that methanol may be responsible for Fe(II) oxidation to Fe(III) necessary for GR formation. Studies with Ar instead of CO2 trigger gas indicated that CO2 is essential for GR formation. Conditions to generate CO32- anionmore » was most likely provided by basic environment of the medium. The nano GR suspension was very reactive and instantaneously oxidized completely to a reddish-brown precipitate upon exposure to ambient atmosphere. The nature of the oxidized sample is not certain. The oxidized product, however, appears to be a mix of ferric green rust- [GR(CO32-]*; major] and ferrihydrite-like minerals. To our knowledge, this is first report of use of environmentally-friendly SWIL reagents to synthesize very reactive nano GR materials.« less

  19. Medium Range Ensembles Flood Forecasts for Community Level Applications

    NASA Astrophysics Data System (ADS)

    Fakhruddin, S.; Kawasaki, A.; Babel, M. S.; AIT

    2013-05-01

    Early warning is a key element for disaster risk reduction. In recent decades, there has been a major advancement in medium range and seasonal forecasting. These could provide a great opportunity to improve early warning systems and advisories for early action for strategic and long term planning. This could result in increasing emphasis on proactive rather than reactive management of adverse consequences of flood events. This can be also very helpful for the agricultural sector by providing a diversity of options to farmers (e.g. changing cropping pattern, planting timing, etc.). An experimental medium range (1-10 days) flood forecasting model has been developed for Bangladesh which provides 51 set of discharge ensembles forecasts of one to ten days with significant persistence and high certainty. This could help communities (i.e. farmer) for gain/lost estimation as well as crop savings. This paper describe the application of ensembles probabilistic flood forecast at the community level for differential decision making focused on agriculture. The framework allows users to interactively specify the objectives and criteria that are germane to a particular situation, and obtain the management options that are possible, and the exogenous influences that should be taken into account before planning and decision making. risk and vulnerability assessment was conducted through community consultation. The forecast lead time requirement, users' needs, impact and management options for crops, livestock and fisheries sectors were identified through focus group discussions, informal interviews and questionnaire survey.

  20. Electromagnetic radiation absorbers and modulators comprising polyaniline

    DOEpatents

    Epstein, Arthur J.; Ginder, John M.; Roe, Mitchell G.; Hajiseyedjavadi, Hamid

    1992-01-01

    A composition for absorbing electromagnetic radiation, wherein said electromagnetic radiation possesses a wavelength generally in the range of from about 1000 Angstroms to about 50 meters, wherein said composition comprises a polyaniline composition of the formula ##STR1## where y can be equal to or greater than zero, and R.sup.1 and R.sup.2 are independently selected from the group containing of H, --OCH.sub.3, --CH.sub.3, --F, --Cl, --Br, --I, NR.sup.3 .sub.2, --NHCOR.sup.3, --OH, --O.sup.-, SR.sup.3, --OCOR.sup.3, --NO.sub.2, --COOH, --COOR.sup.3, --COR.sup.3, --CHO, and --CN, where R.sup.3 is a C.sub.1 to C.sub.8 alkyl, aryl or aralkyl group.

  1. Comparison of Mycobacterium tuberculosis culture using liquid culture medium and Lowenstein Jensen medium in abdominal tuberculosis.

    PubMed

    Shah, Sudeep R; Shenai, Shubhada; Desai, Devendra C; Joshi, Anand; Abraham, Philip; Rodrigues, Camilla

    2010-11-01

    Traditionally, the Lowenstein Jensen (LJ) medium has been used for culturing Mycobacterium tuberculosis. In abdominal tuberculosis (TB), the reported yield from tissue culture is between 20% and 60%. Liquid cultures are reported to give a higher yield but there is little data available in abdominal TB. To compare the yield of TB culture with BACTEC 460TB liquid medium and LJ medium for patients with suspected abdominal TB and determine cost effectiveness. This prospective study was done in consecutive cases with clinical, radiological, endoscopic/surgical, and histological suspicion of abdominal TB. Tissue biopsies obtained at colonoscopy or surgery were processed and plated on LJ medium as well as the BACTEC 460TB system. NAP (ρ-nitro-α-acetylamino-β-hydroxy-propiophenone) differentiation was carried out to determine species. The cost of each method and cost per yield were calculated. Of the 29 cases, 22 cases (76%) were positive on BACTEC 460TB culture while 14 (48%) were positive on LJ medium giving a 64% increment in yield. However, the culture of one patient grew on LJ medium, where the BACTEC 460TB was negative. The additional cost of BACTEC 460TB is Rs. 460 and LJ is Rs. 40. Samples from patients with abdominal TB should be processed on both liquid and LJ medium. For high yield, the use of a liquid culture medium system is essential.

  2. Semipermeable thin-film membranes comprising siloxane, alkoxysilyl and aryloxysilyl oligomers and copolymers

    DOEpatents

    Babcock, W.C.; Friesen, D.T.

    1988-11-01

    Novel semipermeable membranes and thin film composite (TFC) gas separation membranes useful in the separation of oxygen, nitrogen, hydrogen, water vapor, methane, carbon dioxide, hydrogen sulfide, lower hydrocarbons, and other gases are disclosed. The novel semipermeable membranes comprise the polycondensation reaction product of two complementary polyfunctional compounds, each having at least two functional groups that are mutually reactive in a condensation polymerization reaction, and at least one of which is selected from siloxanes, alkoxsilyls and aryloxysilyls. The TFC membrane comprises a microporous polymeric support, the surface of which has the novel semipermeable film formed thereon, preferably by interfacial polymerization.

  3. Semipermeable thin-film membranes comprising siloxane, alkoxysilyl and aryloxysilyl oligomers and copolymers

    DOEpatents

    Babcock, Walter C.; Friesen, Dwayne T.

    1988-01-01

    Novel semiperimeable membranes and thin film composite (TFC) gas separation membranes useful in the separation of oxygen, nitrogen, hydrogen, water vapor, methane, carbon dioxide, hydrogen sulfide, lower hydrocarbons, and other gases are disclosed. The novel semipermeable membranes comprise the polycondensation reaction product of two complementary polyfunctional compounds, each having at least two functional groups that are mutually reactive in a condensation polymerization reaction, and at least one of which is selected from siloxanes, alkoxsilyls and aryloxysilyls. The TFC membrane comprises a microporous polymeric support, the surface of which has the novel semipermeable film formed thereon, preferably by interfacial polymerization.

  4. Catalyst system comprising a first catalyst system tethered to a supported catalyst

    DOEpatents

    Angelici, Robert J.; Gao, Hanrong

    1998-08-04

    The present invention provides new catalyst formats which comprise a supported catalyst tethered to a second and different catalyst by a suitable tethering ligand. A preferred system comprises a heterogeneous supported metal catalyst tethered to a homogeneous catalyst. This combination of homogeneous and heterogeneous catalysts has a sufficient lifetime and unusually high catalytic activity in arene hydrogenations, and potentially many other reactions as well, including, but not limited to hydroformylation, hydrosilation, olefin oxidation, isomerization, hydrocyanation, olefin metathesis, olefin polymerization, carbonylation, enantioselective catalysis and photoduplication. These catalysts are easily separated from the products, and can be reused repeatedly, making these systems very economical.

  5. Effective equations governing an active poroelastic medium

    PubMed Central

    2017-01-01

    In this work, we consider the spatial homogenization of a coupled transport and fluid–structure interaction model, to the end of deriving a system of effective equations describing the flow, elastic deformation and transport in an active poroelastic medium. The ‘active’ nature of the material results from a morphoelastic response to a chemical stimulant, in which the growth time scale is strongly separated from other elastic time scales. The resulting effective model is broadly relevant to the study of biological tissue growth, geophysical flows (e.g. swelling in coals and clays) and a wide range of industrial applications (e.g. absorbant hygiene products). The key contribution of this work is the derivation of a system of homogenized partial differential equations describing macroscale growth, coupled to transport of solute, that explicitly incorporates details of the structure and dynamics of the microscopic system, and, moreover, admits finite growth and deformation at the pore scale. The resulting macroscale model comprises a Biot-type system, augmented with additional terms pertaining to growth, coupled to an advection–reaction–diffusion equation. The resultant system of effective equations is then compared with other recent models under a selection of appropriate simplifying asymptotic limits. PMID:28293138

  6. The spontaneous emission factor for lasers with gain induced waveguiding

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Newstein, M.

    1984-11-01

    The expression for the spontaneous emission factor for lasers with gain induced waveguiding has a factor K, called by Petermann ''the astigmatism parameter.'' This factor has been invoked to explain spectral and dynamic characteristics of this class of lasers. We contend that the widely accepted form of the K factor is based on a derivation which is not appropriate for the typical laser situation where the spontaneous emission factor is much smaller than unity. An alternative derivation is presented which leads to a different form for the K factor. The new expression predicts much smaller values under conditions where themore » previous theory gave values large compared to unity. Petermann's form for the K factor is shown to be relevant to large gain linear amplifiers where the power is amplified spontaneous emission noise. The expression for the power output has Petermann's value of K as a factor. The difference in the two situations is that in the laser oscillator the typical atom of interest couples a small portion of its incoherent spontaneous emission into the dominant mode, whereas in the amplifier only the atoms at the input end are important as sources and their output is converted to a greater degree into the dominant mode through the propagation process. In this analysis the authors use a classical model of radiating point dipoles in a continuous medium characterized by a complex permittivity. Since uncritical use of this model will lead to infinite radiation resistance they address the problem of its self-consistency.« less

  7. A weight-gain-for-gestational-age z score chart for the assessment of maternal weight gain in pregnancy.

    PubMed

    Hutcheon, Jennifer A; Platt, Robert W; Abrams, Barbara; Himes, Katherine P; Simhan, Hyagriv N; Bodnar, Lisa M

    2013-05-01

    To establish the unbiased relation between maternal weight gain in pregnancy and perinatal health, a classification for maternal weight gain is needed that is uncorrelated with gestational age. The goal of this study was to create a weight-gain-for-gestational-age percentile and z score chart to describe the mean, SD, and selected percentiles of maternal weight gain throughout pregnancy in a contemporary cohort of US women. The study population was drawn from normal-weight women with uncomplicated, singleton pregnancies who delivered at the Magee-Womens Hospital in Pittsburgh, PA, 1998-2008. Analyses were based on a randomly selected subset of 648 women for whom serial prenatal weight measurements were available through medical chart record abstraction (6727 weight measurements). The pattern of maternal weight gain throughout gestation was estimated by using a random-effects regression model. The estimates were used to create a chart with the smoothed means, percentiles, and SDs of gestational weight gain for each week of pregnancy. This chart allows researchers to express total weight gain as an age-standardized z score, which can be used in epidemiologic analyses to study the association between pregnancy weight gain and adverse or physiologic pregnancy outcomes independent of gestational age.

  8. Charge Gain, Voltage Gain, and Node Capacitance of the SAPHIRA Detector Pixel by Pixel

    NASA Astrophysics Data System (ADS)

    Pastrana, Izabella M.; Hall, Donald N. B.; Baker, Ian M.; Jacobson, Shane M.; Goebel, Sean B.

    2018-01-01

    The University of Hawai`i Institute for Astronomy has partnered with Leonardo (formerly Selex) in the development of HgCdTe linear mode avalanche photodiode (L-APD) SAPHIRA detectors. The SAPHIRA (Selex Avalanche Photodiode High-speed Infra-Red Array) is ideally suited for photon-starved astronomical observations, particularly near infrared (NIR) adaptive optics (AO) wave-front sensing. I have measured the stability, and linearity with current, of a 1.7-um (10% spectral bandpass) infrared light emitting diode (IR LED) used to illuminate the SAPHIRA and have then utilized this source to determine the charge gain (in e-/ADU), voltage gain (in uV/ADU), and node capacitance (in fF) for each pixel of the 320x256@24um SAPHIRA. These have previously only been averages over some sub-array. Determined from the ratio of the temporal averaged signal level to variance under constant 1.7-um LED illumination, I present the charge gain pixel-by-pixel in a 64x64 sub-array at the center of the active area of the SAPHIRA (analyzed separately as four 32x32 sub-arrays) to be about 1.6 e-/ADU (σ=0.5 e-/ADU). Additionally, the standard technique of varying the pixel reset voltage (PRV) in 10 mV increments and recording output frames for the same 64x64 subarray found the voltage gain per pixel to be about 11.7 uV/ADU (σ=0.2 uV/ADU). Finally, node capacitance was found to be approximately 23 fF (σ=6 fF) utilizing the aforementioned charge and voltage gain measurements. I further discuss the linearity measurements of the 1.7-um LED used in the charge gain characterization procedure.

  9. Effect of intermittent kangaroo mother care on weight gain of low birth weight neonates with delayed weight gain.

    PubMed

    Samra, Nashwa M; Taweel, Amal El; Cadwell, Karin

    2013-01-01

    To evaluate intermittent Kangaroo Mother Care (KMC) with additional opportunities to breastfeed on weight gain of low birth weight (LBW) neonates with delayed weight gain. 40 LBW neonates were followed to see whether KMC with additional opportunities to breastfeed improved weight gain. In the KMC group, the mean age of regaining birth weight was significantly less (15.68 vs. 24.56 days) and the average daily weight gain was significantly higher (22.09 vs. 10.39 g, p < .001) than controls. KMC with additional opportunities to breastfeed was found to be an effective intervention for LBWs with delayed weight gain and should be considered to be an effective strategy.

  10. Alignment of Carbon Nanotubes Comprising Magnetically Sensitive Metal Oxides in Nanofluids

    NASA Technical Reports Server (NTRS)

    Hong, Haiping (Inventor); Peterson, G. P. " Bud" (Inventor)

    2016-01-01

    The present invention is a nanoparticle mixture or suspension or nanofluid comprising nonmagnetically sensitive nanoparticles, magnetically sensitive nanoparticles, and surfactant(s). The present invention also relates to methods of preparing and using the same.

  11. Alignment of Carbon Nanotubes Comprising Magnetically Sensitive Metal Oxides in Nanofluids

    NASA Technical Reports Server (NTRS)

    Peterson, G. P. 'Bud' (Inventor); Hong, Haiping (Inventor)

    2014-01-01

    The present invention is a nanoparticle mixture or suspension or nanofluid comprising nonmagnetically sensitive nanoparticles, magnetically sensitive nanoparticles, and surfactant(s). The present invention also relates to methods of preparing and using the same.

  12. Cuphea: a new plant source of medium-chain fatty acids.

    PubMed

    Graham, S A

    1989-01-01

    The plant genus Cuphea (family Lythraceae) promises to provide a new source of industrially and nutritionally important medium-chain fatty acids, especially of lauric acid now supplied exclusively by coconut and palm kernel oils from foreign sources. The seed lipids of Cuphea were first discovered in the 1960s to contain high percentages of several medium-chain fatty acids, including caprylic, capric, lauric, and myristic acid. Research is still in the early stages, but it is intensifying toward the goal of developing the genus into a new temperate climate crop for production of specialty oils. Given the diversity of Cuphea seed lipid composition and the wide ecological and distributional range of the genus, it may be possible to tailor crops to produce selected fatty acids on demand under a variety of growing conditions. Cuphea comprises about 260 species, most native to the New World tropics. Its morphology, classification, chromosome numbers, distribution, ecology, and folk uses are presented. Seed structure is described and seed lipid composition for 73 species is summarized. Problems in domestication and agronomic progress are reviewed. Knowledge of the biosynthetic mechanism controlling the lipids produced by Cuphea remains very limited. Future research in this area, and particularly successful employment of gene transfer techniques, may allow genes controlling the mechanism to be transferred to an already established seed oil producer such as rapeseed. Presently, both traditional plant breeding techniques and newer biotechnological methods are directed toward Cuphea oilseed development.

  13. Method for pulse control in a laser including a stimulated brillouin scattering mirror system

    DOEpatents

    Dane, C. Brent; Hackel, Lloyd; Harris, Fritz B.

    2007-10-23

    A laser system, such as a master oscillator/power amplifier system, comprises a gain medium and a stimulated Brillouin scattering SBS mirror system. The SBS mirror system includes an in situ filtered SBS medium that comprises a compound having a small negative non-linear index of refraction, such as a perfluoro compound. An SBS relay telescope having a telescope focal point includes a baffle at the telescope focal point which blocks off angle beams. A beam splitter is placed between the SBS mirror system and the SBS relay telescope, directing a fraction of the beam to an alternate beam path for an alignment fiducial. The SBS mirror system has a collimated SBS cell and a focused SBS cell. An adjustable attenuator is placed between the collimated SBS cell and the focused SBS cell, by which pulse width of the reflected beam can be adjusted.

  14. Stimulated Brillouin scattering mirror system, high power laser and laser peening method and system using same

    DOEpatents

    Dane, C Brent [Livermore, CA; Hackel, Lloyd [Livermore, CA; Harris, Fritz B [Rocklin, CA

    2007-04-24

    A laser system, such as a master oscillator/power amplifier system, comprises a gain medium and a stimulated Brillouin scattering SBS mirror system. The SBS mirror system includes an in situ filtered SBS medium that comprises a compound having a small negative non-linear index of refraction, such as a perfluoro compound. An SBS relay telescope having a telescope focal point includes a baffle at the telescope focal point which blocks off angle beams. A beam splitter is placed between the SBS mirror system and the SBS relay telescope, directing a fraction of the beam to an alternate beam path for an alignment fiducial. The SBS mirror system has a collimated SBS cell and a focused SBS cell. An adjustable attenuator is placed between the collimated SBS cell and the focused SBS cell, by which pulse width of the reflected beam can be adjusted.

  15. [Marrow stromal cells cultured in N2-supplemented medium: implications on the generation of neural cells].

    PubMed

    Castillo-Díaz, L; de la Cuétara-Bernal, K; García-Varona, A Y

    Most of the culture system for in vitro maintenance and neural differentiation of marrow stromal cells (MSCs) use synthetic media supplemented with 10 or 20% fetal bovine serum (FBS). Serum, however, is comprised of unknown quantities of undefined substances which could interfere the effect of exogenous substances on neural differentiation of MSCs. AIM. Here we describe survival of MSCs cultured in culture conditions where serum was reduced at 0.5 and 1% using Bottenstein and Sato's N2 formula (1979) and poly-L-lysine (PLL)-coated substrate. Stromal cells isolated from rat femurs were cultivated in Dulbecco's modified Eagle medium at 10, 1, 0.5% FBS or in serum free medium containing N2 formula. In serum free medium or at low serum concentration culture surface was coated with PLL. Cell survival was determined by MTT method or by counting viable cells. Survival of MSCs cultured in N2 supplement was reduced at about 40% of that observed in 10% FBS containing medium. Under these conditions cell morphology was also affected. When N2 containing medium was supplemented with FBS at 0.5 or 1% a significant increase of survival with respect to that observed in N2-supplemented cultures was observed. Cells seeded on PLL-coated surface increased their survival by contrast with their homologous cultures seeded on uncoated surface. The culture system which combines N2 formula with FBS 1% and PLL-coated surface is useful for the maintenance of MSCs. These conditions offer advantages for the study of differentiation of these cells because they reduce the confounding influence of serum. The possible implication of this culture system for the study of neural differentiation by these cells is discussed.

  16. Comparison of Video Head Impulse Test (vHIT) Gains Between Two Commercially Available Devices and by Different Gain Analytical Methods.

    PubMed

    Lee, Sang Hun; Yoo, Myung Hoon; Park, Jun Woo; Kang, Byung Chul; Yang, Chan Joo; Kang, Woo Suk; Ahn, Joong Ho; Chung, Jong Woo; Park, Hong Ju

    2018-06-01

    To evaluate whether video head impulse test (vHIT) gains are dependent on the measuring device and method of analysis. Prospective study. vHIT was performed in 25 healthy subjects using two devices simultaneously. vHIT gains were compared between these instruments and using five different methods of comparing position and velocity gains during head movement intervals. The two devices produced different vHIT gain results with the same method of analysis. There were also significant differences in the vHIT gains measured using different analytical methods. The gain analytic method that compares the areas under the velocity curve (AUC) of the head and eye movements during head movements showed lower vHIT gains than a method that compared the peak velocities of the head and eye movements. The former method produced the vHIT gain with the smallest standard deviation among the five procedures tested in this study. vHIT gains differ in normal subjects depending on the device and method of analysis used, suggesting that it is advisable for each device to have its own normal values. Gain calculations that compare the AUC of the head and eye movements during the head movements show the smallest variance.

  17. Can LENR Energy Gains Exceed 1000?

    NASA Astrophysics Data System (ADS)

    Nagel, David J.

    2011-03-01

    Energy gain is defined as the energy realized from reactions divided by the energy required to produce those reactions. Low Energy Nuclear Reactions (LENR) have already been measured to significantly exceed the energy gain of 10 projected from ITER,possibly 15 years from now. Electrochemical experiments using the Pd-D system have shown energy gains exceeding 10. Gas phase experiments with the Ni-H system were reported to yield energy gains of over 100. Neither of these reports has been adequately verified or reproduced. However, the question in the title still deserves consideration. If, as thought by many, it is possible to trigger nuclear reactions that yield MeV energies with chemical energies of the order of eV, then the most optimistic expectation is that LENR gains could approach one million. Hence, the very tentative answer to the question above is yes. However, if LENR could be initiated with some energy cost, and then continue to ``burn,'' very high energy gains might be realized. Consider a match and a pile of dry logs. The phenomenon termed ``heat after death'' will be examined to see if it might be the initial evidence for nuclear ``burning.''

  18. Medium-chain triglycerides/long-chain triglycerides versus long-chain triglycerides in treatment of cancer patients with major body mass loss. Survival in patients with refractory cachexia.

    PubMed

    Szefel, Jarosław; Kruszewski, Wiesław J; Szajewski, Mariusz; Ciesielski, Maciej; Sobczak, Ewa; Czerepko, Maksymilian; Łysiak-Szydłowska, Wiesława

    2016-01-01

    Currently there are no established guidelines regarding the use of long-chain triglycerides (LCT) vs. medium-chain triglycerides medium-chain triglycerides (MCT)/long-chain triglycerides (LCT) in total parenteral nutrition (TPN). Severe malnutrition of patients with refractory cachexia (RC) often causes their disqualification from invasive methods of treatment thus decreasing their quality of life and survival time. To compare the changes in nutritional state of patients with RC receiving PN with LCT and LCT/MCT lipid emulsions and to assess the influence of enteral nutrition on their survival time. The study group comprised of 50 patients (23 female, 27 male) with a median age of 66 years. Refractory cachexia was diagnosed in them due to dysphagia secondary to solid tumours causing obstruction of the gastrointestinal tract (GT). All patients were qualified for surgical gastrostomy due to contraindications to percutaneous endoscopic gastrostomy. The patients were randomly assigned into one of two groups and perioperatively received either LCT or LCT/MCT. Blood samples were collected four times and tested for: total protein, albumin, prealbumin, and C-reactive protein concentration. Patients received Home Enteral Nutrition after discharge from hospital. Changes in nutritional status parameters were similar among patients receiving lipid emulsions LCT vs. MCT/LCT in TPN for 11 days. The mean survival time of all patients operated to gain enteral access to nutrition was 192 ±268 days, and the median survival was 98 days. Regarding the short-term TPN, the results of the study do not demonstrate any superiority of MCT/LCT lipid emulsions over LCT, or vice versa. The inability to eat significantly accelerates unintended body mass loss among patients with RC. Disqualification from invasive treatment options deprives some patients of the benefits they might have obtained from the surgical access to GT and enteral nutrition.

  19. Medium-chain triglycerides/long-chain triglycerides versus long-chain triglycerides in treatment of cancer patients with major body mass loss. Survival in patients with refractory cachexia

    PubMed Central

    Kruszewski, Wiesław J.; Szajewski, Mariusz; Ciesielski, Maciej; Sobczak, Ewa; Czerepko, Maksymilian; Łysiak-Szydłowska, Wiesława

    2016-01-01

    Introduction Currently there are no established guidelines regarding the use of long-chain triglycerides (LCT) vs. medium-chain triglycerides medium-chain triglycerides (MCT)/long-chain triglycerides (LCT) in total parenteral nutrition (TPN). Severe malnutrition of patients with refractory cachexia (RC) often causes their disqualification from invasive methods of treatment thus decreasing their quality of life and survival time. Aim To compare the changes in nutritional state of patients with RC receiving PN with LCT and LCT/MCT lipid emulsions and to assess the influence of enteral nutrition on their survival time. Material and methods The study group comprised of 50 patients (23 female, 27 male) with a median age of 66 years. Refractory cachexia was diagnosed in them due to dysphagia secondary to solid tumours causing obstruction of the gastrointestinal tract (GT). All patients were qualified for surgical gastrostomy due to contraindications to percutaneous endoscopic gastrostomy. The patients were randomly assigned into one of two groups and perioperatively received either LCT or LCT/MCT. Blood samples were collected four times and tested for: total protein, albumin, prealbumin, and C-reactive protein concentration. Patients received Home Enteral Nutrition after discharge from hospital. Results Changes in nutritional status parameters were similar among patients receiving lipid emulsions LCT vs. MCT/LCT in TPN for 11 days. The mean survival time of all patients operated to gain enteral access to nutrition was 192 ±268 days, and the median survival was 98 days. Conclusions Regarding the short-term TPN, the results of the study do not demonstrate any superiority of MCT/LCT lipid emulsions over LCT, or vice versa. The inability to eat significantly accelerates unintended body mass loss among patients with RC. Disqualification from invasive treatment options deprives some patients of the benefits they might have obtained from the surgical access to GT and enteral

  20. Controlling gain one photon at a time

    PubMed Central

    Schwartz, Gregory W; Rieke, Fred

    2013-01-01

    Adaptation is a salient property of sensory processing. All adaptational or gain control mechanisms face the challenge of obtaining a reliable estimate of the property of the input to be adapted to and obtaining this estimate sufficiently rapidly to be useful. Here, we explore how the primate retina balances the need to change gain rapidly and reliably when photons arrive rarely at individual rod photoreceptors. We find that the weakest backgrounds that decrease the gain of the retinal output signals are similar to those that increase human behavioral threshold, and identify a novel site of gain control in the retinal circuitry. Thus, surprisingly, the gain of retinal signals begins to decrease essentially as soon as background lights are detectable; under these conditions, gain control does not rely on a highly averaged estimate of the photon count, but instead signals from individual photon absorptions trigger changes in gain. DOI: http://dx.doi.org/10.7554/eLife.00467.001 PMID:23682314

  1. Multilayer Electroactive Polymer Composite Material Comprising Carbon Nanotubes

    NASA Technical Reports Server (NTRS)

    Ounaies, Zoubeida (Inventor); Park, Cheol (Inventor); Harrison, Joycelyn S. (Inventor); Holloway, Nancy M. (Inventor); Draughon, Gregory K. (Inventor)

    2009-01-01

    An electroactive material comprises multiple layers of electroactive composite with each layer having unique dielectric, electrical and mechanical properties that define an electromechanical operation thereof when affected by an external stimulus. For example, each layer can be (i) a 2-phase composite made from a polymer with polarizable moieties and an effective amount of carbon nanotubes incorporated in the polymer for a predetermined electromechanical operation, or (ii) a 3-phase composite having the elements of the 2-phase composite and further including a third component of micro-sized to nano-sized particles of an electroactive ceramic incorporated in the polymer matrix.

  2. Effect of Intermittent Kangaroo Mother Care on Weight Gain of Low Birth Weight Neonates With Delayed Weight Gain

    PubMed Central

    Samra, Nashwa M.; Taweel, Amal El; Cadwell, Karin

    2013-01-01

    Objective: To evaluate intermittent Kangaroo Mother Care (KMC) with additional opportunities to breastfeed on weight gain of low birth weight (LBW) neonates with delayed weight gain. Methods: 40 LBW neonates were followed to see whether KMC with additional opportunities to breastfeed improved weight gain. Results: In the KMC group, the mean age of regaining birth weight was significantly less (15.68 vs. 24.56 days) and the average daily weight gain was significantly higher (22.09 vs. 10.39 g, p < .001) than controls. Conclusion: KMC with additional opportunities to breastfeed was found to be an effective intervention for LBWs with delayed weight gain and should be considered to be an effective strategy. PMID:24868132

  3. Bilinearization of the generalized coupled nonlinear Schrödinger equation with variable coefficients and gain and dark-bright pair soliton solutions.

    PubMed

    Chakraborty, Sushmita; Nandy, Sudipta; Barthakur, Abhijit

    2015-02-01

    We investigate coupled nonlinear Schrödinger equations (NLSEs) with variable coefficients and gain. The coupled NLSE is a model equation for optical soliton propagation and their interaction in a multimode fiber medium or in a fiber array. By using Hirota's bilinear method, we obtain the bright-bright, dark-bright combinations of a one-soliton solution (1SS) and two-soliton solutions (2SS) for an n-coupled NLSE with variable coefficients and gain. Crucial properties of two-soliton (dark-bright pair) interactions, such as elastic and inelastic interactions and the dynamics of soliton bound states, are studied using asymptotic analysis and graphical analysis. We show that a bright 2-soliton, in addition to elastic interactions, also exhibits multiple inelastic interactions. A dark 2-soliton, on the other hand, exhibits only elastic interactions. We also observe a breatherlike structure of a bright 2-soliton, a feature that become prominent with gain and disappears as the amplitude acquires a minimum value, and after that the solitons remain parallel. The dark 2-soliton, however, remains parallel irrespective of the gain. The results found by us might be useful for applications in soliton control, a fiber amplifier, all optical switching, and optical computing.

  4. Catalyst system comprising a first catalyst system tethered to a supported catalyst

    DOEpatents

    Angelici, R.J.; Gao, H.

    1998-08-04

    The present invention provides new catalyst formats which comprise a supported catalyst tethered to a second and different catalyst by a suitable tethering ligand. A preferred system comprises a heterogeneous supported metal catalyst tethered to a homogeneous catalyst. This combination of homogeneous and heterogeneous catalysts has a sufficient lifetime and unusually high catalytic activity in arene hydrogenations, and potentially many other reactions as well, including, but not limited to hydroformylation, hydrosilication, olefin oxidation, isomerization, hydrocyanidation, olefin metathesis, olefin polymerization, carbonylation, enantioselective catalysis and photoduplication. These catalysts are easily separated from the products, and can be reused repeatedly, making these systems very economical. 2 figs.

  5. Modification of saccadic gain by reinforcement

    PubMed Central

    Paeye, Céline; Wallman, Josh

    2011-01-01

    Control of saccadic gain is often viewed as a simple compensatory process in which gain is adjusted over many trials by the postsaccadic retinal error, thereby maintaining saccadic accuracy. Here, we propose that gain might also be changed by a reinforcement process not requiring a visual error. To test this hypothesis, we used experimental paradigms in which retinal error was removed by extinguishing the target at the start of each saccade and either an auditory tone or the vision of the target on the fovea was provided as reinforcement after those saccades that met an amplitude criterion. These reinforcement procedures caused a progressive change in saccade amplitude in nearly all subjects, although the rate of adaptation differed greatly among subjects. When we reversed the contingencies and reinforced those saccades landing closer to the original target location, saccade gain changed back toward normal gain in most subjects. When subjects had saccades adapted first by reinforcement and a week later by conventional intrasaccadic step adaptation, both paradigms yielded similar degrees of gain changes and similar transfer to new amplitudes and to new starting positions of the target step as well as comparable rates of recovery. We interpret these changes in saccadic gain in the absence of postsaccadic retinal error as showing that saccade adaptation is not controlled by a single error signal. More generally, our findings suggest that normal saccade adaptation might involve general learning mechanisms rather than only specialized mechanisms for motor calibration. PMID:21525366

  6. CBI: Systems or Medium?

    ERIC Educational Resources Information Center

    Higginbotham-Wheat, Nancy L.

    This paper addresses one area of conflict in decisionmaking in computer-based instruction (CBI) research: the relationship between the researcher's definition of CBI either as a medium or as an integrated system and the design of meaningful research questions. (A medium is defined here as a device for the delivery of instruction, while an…

  7. Resonant Gain Singularities in 1D and 3D Metal/Dielectric Multilayered Nanostructures.

    PubMed

    Caligiuri, Vincenzo; Pezzi, Luigia; Veltri, Alessandro; De Luca, Antonio

    2017-01-24

    We present a detailed study on the resonant gain (RG) phenomena occurring in two nanostructures, in which the presence of dielectric singularities is used to reach a huge amplification of the emitted photons resonantly interacting with the system. The presence of gain molecules in the considered nanoresonator systems makes it possible to obtain optical features that are able to unlock several applications. Two noticeable cases have been investigated: a 1D nanoresonator based on hyperbolic metamaterials and a 3D metal/dielectric spherical multishell. The former has been designed in the framework of the effective medium theory, in order to behave as an epsilon-near-zero-and-pole metamaterial, showing extraordinary light confinement and collimation. Such a peculiarity represents the key to lead to a RG behavior, a condition in which the system is demonstrated to behave as a self-amplifying perfect lens. Very high enhancement and spectral sharpness of 1 nm of the emitted light are demonstrated by means of a transfer matrix method simulation. The latter system consists of a metal/doped-dielectric multishell. A dedicated theoretical approach has been set up to finely engineer its doubly tunable resonant nature. The RG condition has been demonstrated also in this case. Finite element method-based simulations, together with an analytical model, clarify the electric field distribution inside the multishell and suggest the opportunity to use this device as a self-enhanced loss compensated multishell, being a favorable scenario for low-threshold SPASER action. Counterintuitively, exceeding the resonant gain amount of molecules in both systems causes a significant drop in the amplitude of the resonance.

  8. Variable gain for a wind turbine pitch control

    NASA Technical Reports Server (NTRS)

    Seidel, R. C.; Birchenough, A. G.

    1981-01-01

    The gain variation is made in the software logic of the pitch angle controller. The gain level is changed depending upon the level of power error. The control uses low gain for low pitch activity the majority of the time. If the power exceeds ten percent offset above rated, the gain is increased to a higher gain to more effectively limit power. A variable gain control functioned well in tests on the Mod-0 wind turbine.

  9. Contrast Gain Control in Auditory Cortex

    PubMed Central

    Rabinowitz, Neil C.; Willmore, Ben D.B.; Schnupp, Jan W.H.; King, Andrew J.

    2011-01-01

    Summary The auditory system must represent sounds with a wide range of statistical properties. One important property is the spectrotemporal contrast in the acoustic environment: the variation in sound pressure in each frequency band, relative to the mean pressure. We show that neurons in ferret auditory cortex rescale their gain to partially compensate for the spectrotemporal contrast of recent stimulation. When contrast is low, neurons increase their gain, becoming more sensitive to small changes in the stimulus, although the effectiveness of contrast gain control is reduced at low mean levels. Gain is primarily determined by contrast near each neuron's preferred frequency, but there is also a contribution from contrast in more distant frequency bands. Neural responses are modulated by contrast over timescales of ∼100 ms. By using contrast gain control to expand or compress the representation of its inputs, the auditory system may be seeking an efficient coding of natural sounds. PMID:21689603

  10. Computer algorithm for coding gain

    NASA Technical Reports Server (NTRS)

    Dodd, E. E.

    1974-01-01

    Development of a computer algorithm for coding gain for use in an automated communications link design system. Using an empirical formula which defines coding gain as used in space communications engineering, an algorithm is constructed on the basis of available performance data for nonsystematic convolutional encoding with soft-decision (eight-level) Viterbi decoding.

  11. Direct measurements of fluorine atom concentration, gain length and small signal gain in an hydrogen fluoride overtone laser

    NASA Astrophysics Data System (ADS)

    Wisniewski, Charles F.; Hewett, Kevin B.; Manke, Gerald C., II; Randall Truman, C.; Hager, Gordon D.

    2003-03-01

    Experimental techniques have been developed to directly measure the concentration of fluorine atoms, the gain length and the small signal gain in a hydrogen fluoride 5 cm slit nozzle laser. A gas phase titration technique was utilized to measure the fluorine atom concentration using HCl as the titrant. The gain length was measured using a pitot probe to locate the interface of the primary flow with the high Mach number shroud flows. A tunable diode laser was utilized to perform small signal gain measurements on HF overtone ( ν=2→0) transitions.

  12. System comprising interchangeable electronic controllers and corresponding methods

    NASA Technical Reports Server (NTRS)

    Steele, Glen F. (Inventor); Salazar, George A. (Inventor)

    2009-01-01

    A system comprising an interchangeable electronic controller is provided with programming that allows the controller to adapt a behavior that is dependent upon the particular type of function performed by a system or subsystem component. The system reconfigures the controller when the controller is moved from one group of subsystem components to another. A plurality of application programs are provided by a server from which the application program for a particular electronic controller is selected. The selection is based on criteria such as a subsystem component group identifier that identifies the particular type of function associated with the system or subsystem group of components.

  13. 27 CFR 19.914 - Medium plants.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Medium plants. 19.914... OF THE TREASURY LIQUORS DISTILLED SPIRITS PLANTS Distilled Spirits For Fuel Use Permits § 19.914 Medium plants. Any person wishing to establish a medium plant shall make application for and obtain in...

  14. Laser pulse self-compression in an active fibre with a finite gain bandwidth under conditions of a nonstationary nonlinear response

    NASA Astrophysics Data System (ADS)

    Balakin, A. A.; Litvak, A. G.; Mironov, V. A.; Skobelev, S. A.

    2018-04-01

    We study the influence of a nonstationary nonlinear response of a medium on self-compression of soliton-like laser pulses in active fibres with a finite gain bandwidth. Based on the variational approach, we qualitatively analyse the self-action of the wave packet in the system under consideration in order to classify the main evolution regimes and to determine the minimum achievable laser pulse duration during self-compression. The existence of stable soliton-type structures is shown in the framework of the parabolic approximation of the gain profile (in the approximation of the Gnizburg – Landau equation). An analysis of the self-action of laser pulses in the framework of the nonlinear Schrödinger equation with a sign-constant gain profile demonstrate a qualitative change in the dynamics of the wave field in the case of a nonsta­tionary nonlinear response that shifts the laser pulse spectrum from the amplification region and stops the pulse compression. Expressions for a minimum duration of a soliton-like laser pulse are obtained as a function of the problem parameters, which are in good agreement with the results of numerical simulation.

  15. Optimal PID gain schedule for hydrogenerators

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Orelind, G.; Wozniak, L.; Medanic, J.

    1989-09-01

    This paper describes the development and testing of a digital gain switching governor for hydrogenerators. Optimal gains were found at different load points by minimizing a quadratic performance criterion prior to controller operating. During operation, the gain sets are switched in depending on the gate position and speed error magnitude. With gain switching operating, the digital governor was shown to have a substantial reduction of noise on the command signal and up to 42% faster responses to power requests. Non-linear control strategies enabled the digital governor to have a 2.5% to 2% reduction in speed overshoot on startups, and anmore » 8% to 1% reduction in undershoot on load rejections as compared to the analog.« less

  16. Realization of a gain with electromagnetically induced transparency system using non-degenerate Zeeman sublevels in 87 Rb

    NASA Astrophysics Data System (ADS)

    Zhou, Minchuan; Zhou, Zifan; Shahriar, Selim M.

    2017-11-01

    Previously, we had proposed an optically-pumped five-level Gain EIT (GEIT) system, which has a transparency dip superimposed on a gain profile and exhibits a negative dispersion suitable for the white-light-cavity signal-recycling (WLC-SR) scheme of the interferometric gravitational wave detector (Zhou et al., 2015). Using this system as the negative dispersion medium (NDM) in the WLC-SR, we get an enhancement in the quantum noise (QN) limited sensitivity-bandwidth product by a factor of ∼ 18. Here, we show how to realize this GEIT system in a realistic platform, using non-degenerate Zeeman sublevels in cold Rb atoms, employing anomalous dispersion at 795 nm. Using the Caves model for a phase insensitive linear amplifier, we show that an enhancement of the sensitivity-bandwidth product by a factor of ∼ 17 is possible for potentially realizable experimental parameters. While the current LIGO apparatus uses light at 1064 nm, a future embodiment thereof may operate at a wavelength that is consistent with the wavelength considered here.

  17. Sudden Gains During Therapy of Social Phobia

    PubMed Central

    Hofmann, Stefan G.; Schulz, Stefan M.; Meuret, Alicia E.; Moscovitch, David A.; Suvak, Michael

    2007-01-01

    The present study investigated the phenomenon of sudden gains in 107 participants with social phobia (social anxiety disorder) who received either cognitive–behavioral group therapy or exposure group therapy without explicit cognitive interventions, which primarily used public speaking situations as exposure tasks. Twenty-two out of 967 session-to-session intervals met criteria for sudden gains, which most frequently occurred in Session 5. Individuals with sudden gains showed similar improvements in the 2 treatment groups. Although cognitive–behavioral therapy was associated with more cognitive changes than exposure therapy, cognitive changes did not precede sudden gains. In general, the results of this study question the clinical significance of sudden gains in social phobia treatment. PMID:16881776

  18. 49 CFR 195.306 - Test medium.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Test medium. 195.306 Section 195.306... PIPELINE Pressure Testing § 195.306 Test medium. (a) Except as provided in paragraphs (b), (c), and (d) of this section, water must be used as the test medium. (b) Except for offshore pipelines, liquid...

  19. 49 CFR 195.306 - Test medium.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Test medium. 195.306 Section 195.306... PIPELINE Pressure Testing § 195.306 Test medium. (a) Except as provided in paragraphs (b), (c), and (d) of this section, water must be used as the test medium. (b) Except for offshore pipelines, liquid...

  20. Real-world cost-effectiveness of infliximab for moderate-to-severe rheumatoid arthritis in a medium-sized city of China.

    PubMed

    Li, Jingyang; Wen, Zhenhua; Cai, Anlie; Tian, Feng; Zhang, Liang; Luo, Xiaowen; Deng, Li; He, Jingyun; Yang, Yicheng; Chen, Wendong

    2017-05-01

    To assess the cost-effectiveness of infliximab-containing therapy (ICT) for moderate-to-severe rheumatoid arthritis (RA) in a medium-sized Chinese city. A Chinese prospective cohort study comparing ICT (25 patients) versus conventional disease-modified antirheumatic drugs (24 patients) for RA was used to assess the cost-effectiveness of ICT. The cohort study observed significantly reduced disease activity score of 28 joints (coefficient -2.718, p < 0.001), improved EQ-5D (coefficient 0.453, p < 0.001) and increased medical costs (coefficient 1.289, p < 0.001) associated with ICT. The incremental cost-effectiveness ratio per gained quality-adjusted life year for ICT versus disease-modified antirheumatic drugs was 1.897-times of the local gross domestic product per capita. Infliximab was a favorable cost-effective alternative option for moderate-to-severe RA in a medium-sized city of China.

  1. CONDITIONS FOR CSR MICROBUNCHING GAIN SUPPRESSION

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tsai, Cheng Ying; Douglas, David R.; Li, Rui

    The coherent synchrotron radiation (CSR) of a high brightness electron beam traversing a series of dipoles, such as transport arcs, may result in phase space degradation. On one hand, the CSR can perturb electron transverse motion in dispersive regions along the beamline, causing emittance growth. On the other hand, the CSR effect on the longitudinal beam dynamics could result in microbunching gain enhancement. For transport arcs, several schemes have been proposed* to suppress the CSR-induced emittance growth. Similarly, several scenarios have been introduced** to suppress CSR-induced microbunching gain, which however mostly aim for linac-based machines. In this paper we trymore » to provide sufficient conditions for suppression of CSR-induced microbunching gain along a transport arc, analogous to*. Several example lattices are presented, with the relevant microbunching analyses carried out by our semi-analytical Vlasov solver***. The simulation results show that lattices satisfying the proposed conditions indeed have microbunching gain suppressed. We expect this analysis can shed light on lattice design approach that could suppress the CSR-induced microbunching gain.« less

  2. Bacterial Artificial Chromosome Clones of Viruses Comprising the Towne Cytomegalovirus Vaccine

    PubMed Central

    Cui, Xiaohong; Adler, Stuart P.; Davison, Andrew J.; Smith, Larry; Habib, EL-Sayed E.; McVoy, Michael A.

    2012-01-01

    Bacterial artificial chromosome (BAC) clones have proven invaluable for genetic manipulation of herpesvirus genomes. BAC cloning can also be useful for capturing representative genomes that comprise a viral stock or mixture. The Towne live attenuated cytomegalovirus vaccine was developed in the 1970s by serial passage in cultured fibroblasts. Although its safety, immunogenicity, and efficacy have been evaluated in nearly a thousand human subjects, the vaccine itself has been little studied. Instead, genetic composition and in vitro growth properties have been inferred from studies of laboratory stocks that may not always accurately represent the viruses that comprise the vaccine. Here we describe the use of BAC cloning to define the genotypic and phenotypic properties of viruses from the Towne vaccine. Given the extensive safety history of the Towne vaccine, these BACs provide a logical starting point for the development of next-generation rationally engineered cytomegalovirus vaccines. PMID:22187535

  3. Bacterial artificial chromosome clones of viruses comprising the towne cytomegalovirus vaccine.

    PubMed

    Cui, Xiaohong; Adler, Stuart P; Davison, Andrew J; Smith, Larry; Habib, El-Sayed E; McVoy, Michael A

    2012-01-01

    Bacterial artificial chromosome (BAC) clones have proven invaluable for genetic manipulation of herpesvirus genomes. BAC cloning can also be useful for capturing representative genomes that comprise a viral stock or mixture. The Towne live attenuated cytomegalovirus vaccine was developed in the 1970s by serial passage in cultured fibroblasts. Although its safety, immunogenicity, and efficacy have been evaluated in nearly a thousand human subjects, the vaccine itself has been little studied. Instead, genetic composition and in vitro growth properties have been inferred from studies of laboratory stocks that may not always accurately represent the viruses that comprise the vaccine. Here we describe the use of BAC cloning to define the genotypic and phenotypic properties of viruses from the Towne vaccine. Given the extensive safety history of the Towne vaccine, these BACs provide a logical starting point for the development of next-generation rationally engineered cytomegalovirus vaccines.

  4. Effects of Growth Medium on Matrix-Assisted Laser Desorption–Ionization Time of Flight Mass Spectra: a Case Study of Acetic Acid Bacteria

    PubMed Central

    Wieme, Anneleen D.; Spitaels, Freek; Aerts, Maarten; De Bruyne, Katrien; Van Landschoot, Anita

    2014-01-01

    The effect of the growth medium used on the matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) mass spectra generated and its consequences for species and strain level differentiation of acetic acid bacteria (AAB) were determined by using a set of 25 strains. The strains were grown on five different culture media that yielded a total of more than 600 mass spectra, including technical and biological replicates. The results demonstrate that the culture medium can have a profound effect on the mass spectra of AAB as observed in the presence and varying signal intensities of peak classes, in particular when culture media do not sustain optimal growth. The observed growth medium effects do not disturb species level differentiation but strongly affect the potential for strain level differentiation. The data prove that a well-constructed and robust MALDI-TOF mass spectrometry identification database should comprise mass spectra of multiple reference strains per species grown on different culture media to facilitate species and strain level differentiation. PMID:24362425

  5. Broadband mixing of [Formula: see text]-symmetric and [Formula: see text]-broken phases in photonic heterostructures with a one-dimensional loss/gain bilayer.

    PubMed

    Özgün, Ege; Serebryannikov, Andriy E; Ozbay, Ekmel; Soukoulis, Costas M

    2017-11-14

    Combining loss and gain components in one photonic heterostructure opens a new route to efficient manipulation by radiation, transmission, absorption, and scattering of electromagnetic waves. Therefore, loss/gain structures enabling [Formula: see text]-symmetric and [Formula: see text]-broken phases for eigenvalues have extensively been studied in the last decade. In particular, translation from one phase to another, which occurs at the critical point in the two-channel structures with one-dimensional loss/gain components, is often associated with one-way transmission. In this report, broadband mixing of the [Formula: see text]-symmetric and [Formula: see text]-broken phases for eigenvalues is theoretically demonstrated in heterostructures with four channels obtained by combining a one-dimensional loss/gain bilayer and one or two thin polarization-converting components (PCCs). The broadband phase mixing in the four-channel case is expected to yield advanced transmission and absorption regimes. Various configurations are analyzed, which are distinguished in symmetry properties and polarization conversion regime of PCCs. The conditions necessary for phase mixing are discussed. The simplest two-component configurations with broadband mixing are found, as well as the more complex three-component configurations wherein symmetric and broken sets are not yet mixed and appear in the neighbouring frequency ranges. Peculiarities of eigenvalue behaviour are considered for different permittivity ranges of loss/gain medium, i.e., from epsilon-near-zero to high-epsilon regime.

  6. Dual Q-switched laser outputs from a single lasing medium using an intracavity MEMS micromirror array.

    PubMed

    Bauer, Ralf; Lubeigt, Walter; Uttamchandani, Deepak

    2012-09-01

    An intracavity array of individually controlled microelectromechanical system scanning micromirrors was used to actively Q-switch a single side-pumped Nd:YAG gain medium. Two equal power independent laser outputs were simultaneously obtained by separate actuation of two adjacent micromirrors with a combined average output power of 125 mW. Pulse durations of 28 ns FWHM at 8.7 kHz repetition frequency and 34 ns FWHM at 7.9 kHz repetition frequency were observed for the two output beams with beam quality factors M2 of 1.2 and 1.1 and peak powers of 253 W and 232 W, respectively.

  7. Genotypic gain with simultaneous selection of production, nutrition, and culinary traits in cowpea crosses and backcrosses using mixed models.

    PubMed

    Oliveira, D G; Rocha, M M; Damasceno-Silva, K J; Sá, F V; Lima, L R L; Resende, M D V

    2017-08-17

    The aim of this study was to estimate the genotypic gain with simultaneous selection of production, nutrition, and culinary traits in cowpea crosses and backcrosses and to compare different selection indexes. Eleven cowpea populations were evaluated in a randomized complete block design with four replications. Fourteen traits were evaluated, and the following parameters were estimated: genotypic variation coefficient, genotypic determination coefficient, experimental quality indicator and selection reliability, estimated genotypic values ​​- BLUE, genotypic correlation coefficient among traits, and genotypic gain with simultaneous selection of all traits. The genotypic gain was estimated based on tree selection indexes: classical, multiplicative, and the sum of ranks. The genotypic variation coefficient was higher than the environmental variation coefficient for the number of days to start flowering, plant type, the weight of one hundred grains, grain index, and protein concentration. The majority of the traits presented genotypic determination coefficient from medium to high magnitude. The identification of increases in the production components is associated with decreases in protein concentration, and the increase in precocity leads to decreases in protein concentration and cooking time. The index based on the sum of ranks was the best alternative for simultaneous selection of traits in the cowpea segregating populations resulting from the crosses and backcrosses evaluated, with emphasis on the F 4 BC 12 , F 4 C 21 , and F 4 C 12 populations, which had the highest genotypic gains.

  8. Weight gain - unintentional

    MedlinePlus

    ... Cushing syndrome Underactive thyroid, or low thyroid (hypothyroidism) Polycystic ovary syndrome Menopause Pregnancy Bloating, or swelling due to a buildup of fluid in the tissues can cause weight gain. This may be due to menstruation, heart ...

  9. Reflection-refraction of attenuated waves at the interface between a thermo-poroelastic medium and a thermoelastic medium

    NASA Astrophysics Data System (ADS)

    Sharma, M. D.

    2018-07-01

    Phenomenon of reflection and refraction is considered at the plane interface between a thermoelastic medium and thermo-poroelastic medium. Both the media are isotropic and behave dissipative to wave propagation. Incident wave in thermo-poroelastic medium is considered inhomogeneous with deviation allowed between the directions of propagation and maximum attenuation. For this incidence, four attenuated waves reflect back in thermo-poroelastic medium and three waves refract to the continuing thermoelastic medium. Each of these reflected/refracted waves is inhomogeneous and propagates with a phase shift. The propagation characteristics (velocity, attenuation, inhomogeneity, phase shift, amplitude, energy) of reflected and refracted waves are calculated as functions of propagation direction and inhomogeneity of the incident wave. Variations in these propagation characteristics with the incident direction are illustrated through a numerical example.

  10. Is Weight Gain after Smoking Cessation Inevitable?

    ERIC Educational Resources Information Center

    Talcott, Gerald W.; And Others

    1995-01-01

    Studied weight gain after smoking cessation in a naturalistic setting where all smokers quit and risk factors for postcessation weight gain were modified. Results showed no significant weight changes for smokers who quit. Suggests that an intensive program featuring dietary guidelines and increased physical activity can attenuate weight gain. (RJM)

  11. Approximate reversibility in the context of entropy gain, information gain, and complete positivity

    NASA Astrophysics Data System (ADS)

    Buscemi, Francesco; Das, Siddhartha; Wilde, Mark M.

    2016-06-01

    There are several inequalities in physics which limit how well we can process physical systems to achieve some intended goal, including the second law of thermodynamics, entropy bounds in quantum information theory, and the uncertainty principle of quantum mechanics. Recent results provide physically meaningful enhancements of these limiting statements, determining how well one can attempt to reverse an irreversible process. In this paper, we apply and extend these results to give strong enhancements to several entropy inequalities, having to do with entropy gain, information gain, entropic disturbance, and complete positivity of open quantum systems dynamics. Our first result is a remainder term for the entropy gain of a quantum channel. This result implies that a small increase in entropy under the action of a subunital channel is a witness to the fact that the channel's adjoint can be used as a recovery map to undo the action of the original channel. We apply this result to pure-loss, quantum-limited amplifier, and phase-insensitive quantum Gaussian channels, showing how a quantum-limited amplifier can serve as a recovery from a pure-loss channel and vice versa. Our second result regards the information gain of a quantum measurement, both without and with quantum side information. We find here that a small information gain implies that it is possible to undo the action of the original measurement if it is efficient. The result also has operational ramifications for the information-theoretic tasks known as measurement compression without and with quantum side information. Our third result shows that the loss of Holevo information caused by the action of a noisy channel on an input ensemble of quantum states is small if and only if the noise can be approximately corrected on average. We finally establish that the reduced dynamics of a system-environment interaction are approximately completely positive and trace preserving if and only if the data processing

  12. Collaborative Manufacturing for Small-Medium Enterprises

    NASA Astrophysics Data System (ADS)

    Irianto, D.

    2016-02-01

    Manufacturing systems involve decisions concerning production processes, capacity, planning, and control. In a MTO manufacturing systems, strategic decisions concerning fulfilment of customer requirement, manufacturing cost, and due date of delivery are the most important. In order to accelerate the decision making process, research on decision making structure when receiving order and sequencing activities under limited capacity is required. An effective decision making process is typically required by small-medium components and tools maker as supporting industries to large industries. On one side, metal small-medium enterprises are expected to produce parts, components or tools (i.e. jigs, fixture, mold, and dies) with high precision, low cost, and exact delivery time. On the other side, a metal small- medium enterprise may have weak bargaining position due to aspects such as low production capacity, limited budget for material procurement, and limited high precision machine and equipment. Instead of receiving order exclusively, a small-medium enterprise can collaborate with other small-medium enterprise in order to fulfill requirements high quality, low manufacturing cost, and just in time delivery. Small-medium enterprises can share their best capabilities to form effective supporting industries. Independent body such as community service at university can take a role as a collaboration manager. The Laboratory of Production Systems at Bandung Institute of Technology has implemented shared manufacturing systems for small-medium enterprise collaboration.

  13. Development of the Exercise Motives and Gains Inventory

    ERIC Educational Resources Information Center

    Strömmer, Sofia T.; Ingledew, David K.; Markland, David

    2015-01-01

    There are existing measures of exercise motives (what people want from exercise), but corresponding measures of gains (what people get) are needed, because motives and gains could influence each other and together influence other variables. An exercise motives and gains inventory (EMGI) was developed by creating gains scales to complement existing…

  14. Nicotine Replacement: Effects on Postcessation Weight Gain.

    ERIC Educational Resources Information Center

    Gross, Janet; And Others

    1989-01-01

    Examined nicotine replacement effects on postcessation weight gain in smoking cessation volunteers. Randomly assigned abstinent subjects to active nicotine or placebo gum conditions for 10 weeks. Analyses revealed strong evidence for gum effect on weight gain, with active gum users gaining mean total of 3.8 pounds compared with 7.8 pounds for…

  15. Insulin detemir attenuates food intake, body weight gain and fat mass gain in diet-induced obese Sprague-Dawley rats.

    PubMed

    Rojas, J M; Printz, R L; Niswender, K D

    2011-07-04

    Initiation and intensification of insulin therapy commonly causes weight gain, a barrier to therapy. A contrasting body of evidence indicates that insulin functions as an adiposity negative feedback signal and reduces food intake, weight gain and adiposity via action in the central nervous system. Basal insulin analogs, detemir (Det) and glargine (Glar), have been associated with less hypoglycemia compared with neutral protamine hagedorn insulin, and Det with less weight gain, especially in patients with higher body mass index (BMI). We sought to determine whether insulin therapy per se causes body weight and fat mass gain when delivered via a clinically relevant subcutaneous (SC) route in the absence of hypoglycemia and glycosuria in non-diabetic lean and diet-induced obese rats. Rats were exposed to either a low-fat diet (LFD; 13.5% fat) or high-fat diet (HFD; 60% fat), and received Det (0.5 U kg(-1)), Glar (0.2 U kg(-1)) or vehicle (Veh) SC once daily for 4 weeks. These dosages of insulin were equipotent in rats with respect to blood-glucose concentration and did not induce hypoglycemia. As predicted by current models of energy homeostasis, neither insulin Det nor Glar therapy affected food intake and weight gain in LFD rats. Det treatment significantly attenuated food intake, body weight gain and fat mass gain relative to the Glar and Veh in high-fat fed animals, mirroring observations in humans. That neither insulin group gained excess weight, suggests weight gain with SC basal insulin therapy may not be inevitable. Our data further suggest that Det possesses a unique property to attenuate the development of obesity associated with a HFD.

  16. Differential foraging preferences on seed size by rodents result in higher dispersal success of medium-sized seeds.

    PubMed

    Cao, Lin; Wang, Zhenyu; Yan, Chuan; Chen, Jin; Guo, Cong; Zhang, Zhibin

    2016-11-01

    Rodent preference for scatter-hoarding large seeds has been widely considered to favor the evolution of large seeds. Previous studies supporting this conclusion were primarily based on observations at earlier stages of seed dispersal, or on a limited sample of successfully established seedlings. Because seed dispersal comprises multiple dispersal stages, we hypothesized that differential foraging preference on seed size by animal dispersers at different dispersal stages would ultimately result in medium-sized seeds having the highest dispersal success rates. In this study, by tracking a large number of seeds for 5 yr, we investigated the effects of seed size on seed fates from seed removal to seedling establishment of a dominant plant Pittosporopsis kerrii (Icacinaceae) dispersed by scatter-hoarding rodents in tropical forest in southwest China. We found that small seeds had a lower survival rate at the early dispersal stage where more small seeds were predated at seed stations and after removal; large seeds had a lower survival rate at the late dispersal stage, more large seeds were recovered, predated after being cached, or larder-hoarded. Medium-sized seeds experienced the highest dispersal success. Our study suggests that differential foraging preferences by scatter-hoarding rodents at different stages of seed dispersal could result in conflicting selective pressures on seed size and higher dispersal success of medium-sized seeds. © 2016 by the Ecological Society of America.

  17. Personality type influence the gestational weight gain.

    PubMed

    Franik, Grzegorz; Lipka, Nela; Kopyto, Katarzyna; Kopocińska, Joanna; Owczarek, Aleksander; Sikora, Jerzy; Madej, Paweł; Chudek, Jerzy; Olszanecka-Glinianowicz, Magdalena

    2017-08-01

    Pregnancy is frequently followed by the development of obesity. Aside from psychological factors, hormonal changes influence weight gain in pregnant women. We attempted to assess the potential association between personality type and the extent of gestational weight gain. The study group involved 773 women after term delivery (age 26.3 ± 3.9 years, body mass before pregnancy 61.2 ± 11.1 kg). Weight gain during pregnancy was calculated by using self-reported body mass prior to and during the 38th week of pregnancy. Personality type was assessed using the Polish version of the Framingham Type A Behavior Patterns Questionnaire (adapted by Juczynski). Two hundred forty-six (31.8%) study subjects represented type A personalities, 272 (35.2%) type B and 255 (33.0%) an indirect type. Gestational weight gain was related to the behavior patterns questionnaire score and age. In women <30 years with type A personality, the weight gain was higher than in women with type B behavior of the same age. In women >30, the gestational weight gain was larger for type B personalities. Type A personality and increased urgency in younger pregnant women increases the risk of developing obesity during pregnancy in women below 30 years old. A higher level of competitiveness demonstrates a risk factor of excessive weight gain during pregnancy regardless of age.

  18. IQ Gains in Argentina between 1964 and 1998

    ERIC Educational Resources Information Center

    Flynn, James R.; Rossi-Case, Lilia

    2012-01-01

    The literature on IQ gains in Latin America is sparse. We estimate gains on Raven's Progressive Matrices in the city of La Plata (Argentina) between 1964 and 1998. The gains are robust at the top of the curve as well as at the bottom. Therefore, they are contrary to the hypothesis that nutrition played a major role in recent Argentine IQ gains.…

  19. Electric circuit breaker comprising a plurality of vacuum interrupters simultaneously operated by a common operator

    DOEpatents

    Barkan, Philip; Imam, Imdad

    1980-01-01

    This circuit breaker comprises a plurality of a vacuum-type circuit interrupters, each having a movable contact rod. A common operating device for the interrupters comprises a linearly-movable operating member. The interrupters are mounted at one side of the operating member with their movable contact rods extending in a direction generally toward the operating member. Means is provided for mechanically coupling the operating member to the contact rods, and this means comprises a plurality of insulating operating rods, each connected at one end to the operating member and at its opposite end to one of the movable contact rods. The operating rods are of substantially equal length and have longitudinal axes that converge and intersect at substantially a common point.

  20. Reflex ring laser amplifier system

    DOEpatents

    Summers, M.A.

    1983-08-31

    The invention is a method and apparatus for providing a reflex ring laser system for amplifying an input laser pulse. The invention is particularly useful in laser fusion experiments where efficient production of high-energy and high power laser pulses is required. The invention comprises a large aperture laser amplifier in an unstable ring resonator which includes a combination spatial filter and beam expander having a magnification greater than unity. An input pulse is injected into the resonator, e.g., through an aperture in an input mirror. The injected pulse passes through the amplifier and spatial filter/expander components on each pass around the ring. The unstable resonator is designed to permit only a predetermined number of passes before the amplified pulse exits the resonator. On the first pass through the amplifier, the beam fills only a small central region of the gain medium. On each successive pass, the beam has been expanded to fill the next concentric non-overlapping region of the gain medium.

  1. Structural and biophysical characterization of an antimicrobial peptide chimera comprised of lactoferricin and lactoferrampin.

    PubMed

    Haney, Evan F; Nazmi, Kamran; Bolscher, Jan G M; Vogel, Hans J

    2012-03-01

    Lactoferricin and lactoferrampin are two antimicrobial peptides found in the N-terminal lobe of bovine lactoferrin with broad spectrum antimicrobial activity against a range of Gram-positive and Gram-negative bacteria as well as Candida albicans. A heterodimer comprised of lactoferrampin joined to a fragment of lactoferricin was recently reported in which these two peptides were joined at their C-termini through the two amino groups of a single Lys residue (Bolscher et al., 2009, Biochimie 91(1):123-132). This hybrid peptide, termed LFchimera, has significantly higher antimicrobial activity compared to the individual peptides or an equimolar mixture of the two. In this work, the underlying mechanism behind the increased antibacterial activity of LFchimera was investigated. Differential scanning calorimetry studies demonstrated that all the peptides influenced the thermotropic phase behaviour of anionic phospholipid suspensions. Calcein leakage and vesicle fusion experiments with anionic liposomes revealed that LFchimera had enhanced membrane perturbing properties compared to the individual peptides. Peptide structures were evaluated using circular dichroism and NMR spectroscopy to gain insight into the structural features of LFchimera that contribute to the increased antimicrobial activity. The NMR solution structure, determined in a miscible co-solvent mixture of chloroform, methanol and water, revealed that the Lys linkage increased the helical content in LFchimera compared to the individual peptides, but it did not fix the relative orientations of lactoferricin and lactoferrampin with respect to each other. The structure of LFchimera provides insight into the conformation of this peptide in a membranous environment and improves our understanding of its antimicrobial mechanism of action. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Loss restlessness and gain calmness: durable effects of losses and gains on choice switching.

    PubMed

    Yechiam, Eldad; Zahavi, Gal; Arditi, Eli

    2015-08-01

    While the traditional conceptualization of the effect of losses focuses on bias in the subjective weight of losses compared with respective gains, some accounts suggest more global task-related effects of losses. Based on a recent attentional theory, we predicted a positive after-effect of losses on choice switching in later tasks. In two experimental studies, we found increased choice switching rates in tasks with losses compared to tasks with no losses. Additionally, this heightened shifting behavior was maintained in subsequent tasks that do not include losses, a phenomenon we refer to as "loss restlessness." Conversely, gains were found to have an opposite "calming" effect on choice switching. Surprisingly, the loss restlessness phenomenon was observed following an all-losses payoff regime but not after a task with symmetric mixed gains and losses. This suggests that the unresolved mental account following an all-losses regime increases search behavior. Potential implications to macro level phenomena, such as the leverage effect, are discussed.

  3. Polymicrobial biofilm formation by Candida albicans, Actinomyces naeslundii, and Streptococcus mutans is Candida albicans strain and medium dependent.

    PubMed

    Arzmi, Mohd Hafiz; Alnuaimi, Ali D; Dashper, Stuart; Cirillo, Nicola; Reynolds, Eric C; McCullough, Michael

    2016-11-01

    Oral biofilms comprise of extracellular polysaccharides and polymicrobial microorganisms. The objective of this study was to determine the effect of polymicrobial interactions of Candida albicans, Actinomyces naeslundii, and Streptococcus mutans on biofilm formation with the hypotheses that biofilm biomass and metabolic activity are both C. albicans strain and growth medium dependent. To study monospecific biofilms, C. albicans, A. naeslundii, and S. mutans were inoculated into artificial saliva medium (ASM) and RPMI-1640 in separate vials, whereas to study polymicrobial biofilm formation, the inoculum containing microorganisms was prepared in the same vial prior inoculation into a 96-well plate followed by 72 hours incubation. Finally, biofilm biomass and metabolic activity were measured using crystal violet and XTT assays, respectively. Our results showed variability of monospecies and polymicrobial biofilm biomass between C. albicans strains and growth medium. Based on cut-offs, out of 32, seven RPMI-grown biofilms had high biofilm biomass (HBB), whereas, in ASM-grown biofilms, 14 out of 32 were HBB. Of the 32 biofilms grown in RPMI-1640, 21 were high metabolic activity (HMA), whereas in ASM, there was no biofilm had HMA. Significant differences were observed between ASM and RPMI-grown biofilms with respect to metabolic activity (P <01). In conclusion, biofilm biomass and metabolic activity were both C. albicans strain and growth medium dependent. © The Author 2016. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. High statistics study of in-medium S- and P-wave quarkonium states in lattice Non-relativistic QCD

    NASA Astrophysics Data System (ADS)

    Kim, S.; Petreczky, P.; Rothkopf, A.

    2017-11-01

    Many measurements of quarkonium suppression at the LHC, e.g. the nuclear modification factor RAA of J / Ψ, are well described by a multitude of different models. Thus pinpointing the underlying physics aspects is difficult and guidance based on first principles is needed. Here we present the current status of our ongoing high precision study of in-medium spectral properties of both bottomonium and charmonium based on NRQCD on the lattice. This effective field theory allows us to capture the physics of quarkonium without modeling assumptions in a thermal QCD medium. In our study a first principles and realistic description of the QCD medium is provided by state-of-the-art lattices of the HotQCD collaboration at almost physical pion mass. Our updated results corroborate a picture of sequential modification of states with respect to their vacuum binding energy. Using a novel low-gain variant of the Bayesian BR method for reconstructing spectral functions we find that remnant features of the Upsilon may survive up to T ∼ 400MeV, while the χb signal disappears around T ∼ 270MeV. The c c ‾ analysis hints at melting of χc below T ∼ 190MeV while some J / Ψ remnant feature might survive up to T ∼ 245MeV. An improved understanding of the numerical artifacts in the Bayesian approach and the availability of increased statistics have made possible a first quantitative study of the in-medium ground state masses, which tend to lower values as T increases, consistent with lattice potential based studies.

  5. Gain scheduling - Potential hazards and possible remedies

    NASA Technical Reports Server (NTRS)

    Shamma, Jeff S.; Athans, Michael

    1991-01-01

    A common gain scheduling rule-of-thumb is to schedule on a slow variable. In this work, it is shown how current gain scheduling practice is necessarily limited to slow variations in the scheduling variable. These limitations are revealed to be consequences of fundamental control concepts. Furthermore, it is shown how a formulation of the gain scheduling procedure can lead toward ultimately removing these restrictions.

  6. Degradation testing of Mg alloys in Dulbecco's modified eagle medium: Influence of medium sterilization.

    PubMed

    Marco, Iñigo; Feyerabend, Frank; Willumeit-Römer, Regine; Van der Biest, Omer

    2016-05-01

    This work studies the in vitro degradation of Mg alloys for bioabsorbable implant applications under near physiological conditions. For this purpose, the degradation behaviour of Mg alloys in Dulbecco's modified eagle medium (DMEM) which is a commonly used cell culture medium is analysed. Unfortunately, DMEM can be contaminated by microorganisms, acidifying the medium and accelerating the Mg degradation process by dissolution of protective degradation layers, such as (Mgx,Cay)(PO4)z. In this paper the influence of sterilization by applying UV-C radiation and antibiotics (penicillin/streptomycin) is analysed with two implant material candidates: Mg-Gd and Mg-Ag alloys; and pure magnesium as well as Mg-4Y-3RE as a reference. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Choice of Scottish Gaelic-Medium and Welsh-Medium Education at the Primary and Secondary School Stages: Parent and Pupil Perspectives

    ERIC Educational Resources Information Center

    O'Hanlon, Fiona

    2015-01-01

    Results are presented of a comparative study of the reasons for parental choice of Scottish Gaelic-medium and Welsh-medium primary education in the year 2000 and of the reasons for pupils' decisions to continue with Gaelic or Welsh-medium education at secondary school in 2007. Parents in both contexts cited the quality of Celtic-medium education…

  8. [Antipsychotic-induced weight gain--pharmacogenetic studies].

    PubMed

    Olajossy-Hilkesberger, Luiza; Godlewska, Beata; Marmurowska-Michałowskal, Halina; Olajossy, Marcin; Landowski, Jerzy

    2006-01-01

    Drug-naive patients with schizophrenia often present metabolic abnormalities and obesity. Weight gain may be the side effect of treatment with many antipsychotic drugs. Genetic effects, besides many other factors, are known to influence obesity in patients with schizophrenia treated with antipsychotics. Numerous studies of several genes' polymorphisms have been performed. -759C/T polymorphism of 5HT2C gene attracted most attention. In 5 independent studies of this polymorphism the association between T allele with the lower AP-induced weight gain was detected. No associations could be detected between weight gain and other polymorphisms of serotonergic system genes as well as histaminergic system genes. Studies of adrenergic and dopaminergic system have neither produced any unambiguous results. Analysis of the newest candidate genes (SAP-25, leptin gene) confirmed the role of genetic factors in AP-induced weight gain. It is worth emphasising, that the studies have been conducted in relatively small and heterogenic groups and that various treatment strategies were used.

  9. A Simple Ultra-Wideband Magneto-Electric Dipole Antenna With High Gain

    NASA Astrophysics Data System (ADS)

    Shuai, Chen-yang; Wang, Guang-ming

    2017-12-01

    A simple ultra-wideband magneto-electric dipole antenna utilizing a differential-fed structure is designed. The antenna mainly comprises three parts, including a novel circular horned reflector, two vertical semicircular shorted patches as a magnetic dipole, and a horizontal U-shaped semicircular electric dipole. A differential feeding structure working as a perfect balun excites the designed antenna. The results of simulation have a good match with the ones of measurement. Results indicate that the designed antenna achieves a wide frequency bandwidth of 107 % which is 3.19 10.61 GHz, when VSWR is below 2. Via introducing the circular horned reflector, the designed antenna attains a steady and high gain of 12±1.5dBi. Moreover, settled broadside direction main beam, high front-to-back ratio, low cross polarization, and the symmetrical and relatively stable radiation patterns in the E-and H-plane are gotten in the impedance bandwidth range. In the practical applications, the proposed antenna that is dc grounded and has a simple structure satisfies the requirement of many outdoor antennas.

  10. Cost-effectiveness of iso- versus low-osmolality contrast media in outpatients with high risk of contrast medium-induced nephropathy.

    PubMed

    Chicaíza-Becerra, Liliana Alejandra; García-Molina, Mario; Gamboa, Óscar

    2012-06-01

    Contrast media can cause acute renal failure by direct toxic effects on the tubular cells and kidney ischemia. Diabetics and hospitalized patients have a greater risk of developing contrast-induced nephropathy than the general population. The cost effectiveness of iso and low-osmolality contrast media was assessed in high risk outpatients. The analysis was based on a systematic literature review comparing the nephrotoxic effects of iso- to low-osmolality contrast media. Only direct costs were considered; these were obtained from the official tariff manual. Incremental cost-effectiveness ratios, efficiency curves and acceptability curves were calculated. Univariate sensitivity analyses were performed for costs and effects, as well as probabilistic analyses. Zero and 3% discounts were applied to results. The cost-effectiveness threshold was equal to the per capita GDP per life-year gained. Alternatives with Iopamidol and Iodixanol are preferable to the others, because both reduce risk of contrast-induced nephropathy and are less costly. The incremental cost-effectiveness of the Iodixanol alternative compared to the Iopamidol alternative is US$ 14,660 per additional life year gained; this is more than twice the threshold. The low-osmolality contrast medium, Iopamidol, appears to be cost-effective when compared with Iohexol or other low-osmolality contrast media (Iopromide, Iobitridol, Iomeprol, Iopentol and Ioxilan) in contrast-induced nephropathy, high-risk outpatients. The choice of the iso-osmolality contrast medium, Iodixanol, depends on its cost per vial and on the willingness to pay.

  11. Designing and Creating a Synthetic Omega Oxidation Pathway in Saccharomyces cerevisiae Enables Production of Medium-Chain α, ω-Dicarboxylic Acids

    PubMed Central

    Han, Li; Peng, Yanfeng; Zhang, Yuangyuan; Chen, Wujiu; Lin, Yuping; Wang, Qinhong

    2017-01-01

    Medium-chain (C8–C14) α, ω-dicarboxylic acids (α, ω-DCAs), which have numerous applications as raw materials for producing various commodities and polymers in chemical industry, are mainly produced from chemical or microbial conversion of petroleum-derived alkanes or plant-derived fatty acids at present. Recently, significant attention has been gained to microbial production of medium-chain α, ω-DCAs from simple renewable sugars. Here, we designed and created a synthetic omega oxidation pathway in Saccharomyces cerevisiae to produce C10 and C12 α, ω-DCAs from renewable sugars and fatty acids by introducing a heterogeneous cytochrome P450 CYP94C1 and cytochrome reductase ATR1. Furthermore, the deletion of fatty acyl-CoA synthetase genes FAA1 and FAA4 increased the production of medium-chain α, ω-DCAs from 4.690 ± 0.088 mg/L to 12.177 ± 0.420 mg/L and enabled the production of C14 and C16 α, ω-DCAs at low percentage. But blocking β-oxidation pathway by deleting fatty-acyl coenzyme A oxidase gene POX1 and overexpressing different thioesterase genes had no significant impact on the production and the composition of α, ω-dicarboxylic acids. Overall, our study indicated the potential of microbial production of medium-chain α, ω-DCAs from renewable feedstocks using engineered yeast. PMID:29163455

  12. Method and device for fabricating dispersion fuel comprising fission product collection spaces

    DOEpatents

    Shaber, Eric L; Fielding, Randall S

    2015-05-05

    A method of fabricating a nuclear fuel comprising a fissile material, one or more hollow microballoons, a phenolic resin, and metal matrix. The fissile material, phenolic resin and the one or more hollow microballoons are combined. The combined fissile material, phenolic resin and the hollow microballoons are heated sufficiently to form at least some fissile material carbides creating a nuclear fuel particle. The resulting nuclear fuel particle comprises one or more fission product collection spaces. In a preferred embodiment, the fissile material, phenolic resin and the one or more hollow microballoons are combined by forming the fissile material into microspheres. The fissile material microspheres are then overcoated with the phenolic resin and microballoon. In another preferred embodiment, the fissile material, phenolic resin and the one or more hollow microballoons are combined by overcoating the microballoon with the fissile material, and phenolic resin.

  13. Constraints on quantum information field and “human gain medium” making possible functioning of social laser

    NASA Astrophysics Data System (ADS)

    Khrennikov, Andrei

    2017-08-01

    Starting with the quantum-like paradigm on application of quantum information and probability outside of physics we proceed to the social laser model describing Stimulated Amplification of Social Actions (SASA). The basic components of social laser are the quantum information field carrying information excitations and the human gain medium. The aim of this note is to analyze constraints on these components making possible SASA. The soical laser model can be used to explain the recent wave of color revolutions as well as such “unpredictable events” as Brexit and election of Donald Trump as the president of the United States of America. The presented quantum-like model is not only descriptive. We shall list explicitly conditions for creation of social laser.

  14. The violent interstellar medium

    NASA Technical Reports Server (NTRS)

    Mccray, R.; Snow, T. P., Jr.

    1979-01-01

    Observational evidence for high-velocity and high-temperature interstellar gas is reviewed. The physical processes that characterize this gas are described, including the ionization and emissivity of coronal gas, the behavior and appearance of high-velocity shocks, and interfaces between coronal gas and cooler interstellar gas. Hydrodynamical models for the action of supernova explosions and stellar winds on the interstellar medium are examined, and recent attempts to synthesize all the processes considered into a global model for the interstellar medium are discussed.

  15. 26 CFR 1.737-1 - Recognition of precontribution gain.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Property A1 and Property A2 is long-term, U.S.-source capital gain or loss. The character of gain on Property A3 is long-term, foreign-source capital gain. B contributes Property B, nondepreciable real... long-term, U.S.-source capital gain ($10,000 gain on Property A1 and $8,000 loss on Property A2) and $1...

  16. Gain and energy storage in holmium YLF

    NASA Technical Reports Server (NTRS)

    Storm, Mark E.; Deyst, John P.

    1991-01-01

    It is demonstrated that Q-switched holmium lasers are capable of high-gain and high-energy operation at 300 K. Small-signal gain coefficients of 0.50 and 0.12/cm have been measured in YLF and YAG, respectively. Small-signal gains of 0.50/cm are comparable to those achievable in Nd:YAG and are not typical of low-gain materials. This large gain in the Ho:YLF material is made possible by operating the amplifier in the ground state depletion mode. The amplifier performance data and associated analysis presented demonstrate that efficient energy storage is possible with very high excited state ion densities of the Ho 5I7 upper laser level. This is an important result since upconversion can limit the 5I7 population. Although upconversion was still present in this experiment, it was possible to achieve efficient energy storage, demonstrating that the problem is manageable even at high excitation densities in YLF.

  17. [Atypical antipsychotic-induced weight gain].

    PubMed

    Godlewska, Beata R; Olajossy-Hilkesberger, Luiza; Marmurowska-Michałowska, Halina; Olajossy, Marcin; Landowski, Jerzy

    2006-01-01

    Introduction of a new group of antipsychotic drugs, called atypical because of the proprieties differing them from classical neuroleptics, gave hope for the beginning of a new era in treatment of psychoses, including schizophrenia. Different mechanisms of action not only resulted in a broader spectrum of action and high efficacy but also in a relative lack of extrapiramidal symptoms. However, atypical neuroleptics are not totally free from adverse effects. Symptoms such as sedation, metabolic changes and weight gain, often very quick and severe - present also in the case of classical drugs, but put to the background by extrapiramidal symptoms--have become prominent. Weight gain is important both from the clinical and subjective point of view--as associated with serious somatic consequences and as a source of enormous mental distress. These problems are addressed in this review, with the focus on weight gain associated with the use of specific atypical neuroleptics.

  18. High current gain transistor laser

    PubMed Central

    Liang, Song; Qiao, Lijun; Zhu, Hongliang; Wang, Wei

    2016-01-01

    A transistor laser (TL), having the structure of a transistor with multi-quantum wells near its base region, bridges the functionality gap between lasers and transistors. However, light emission is produced at the expense of current gain for all the TLs reported up to now, leading to a very low current gain. We propose a novel design of TLs, which have an n-doped InP layer inserted in the emitter ridge. Numerical studies show that a current flow aperture for only holes can be formed in the center of the emitter ridge. As a result, the common emitter current gain can be as large as 143.3, which is over 15 times larger than that of a TL without the aperture. Besides, the effects of nonradiative recombination defects can be reduced greatly because the flow of holes is confined in the center region of the emitter ridge. PMID:27282466

  19. Optimal gains for a single polar orbiting satellite

    NASA Technical Reports Server (NTRS)

    Banfield, Don; Ingersoll, A. P.; Keppenne, C. L.

    1993-01-01

    Gains are the spatial weighting of an observation in its neighborhood versus the local values of a model prediction. They are the key to data assimilation, as they are the direct measure of how the data are used to guide the model. As derived in the broad context of data assimilation by Kalman and in the context of meteorology, for example, by Rutherford, the optimal gains are functions of the prediction error covariances between the observation and analysis points. Kalman introduced a very powerful technique that allows one to calculate these optimal gains at the time of each observation. Unfortunately, this technique is both computationally expensive and often numerically unstable for dynamical systems of the magnitude of meteorological models, and thus is unsuited for use in PMIRR data assimilation. However, the optimal gains as calculated by a Kalman filter do reach a steady state for regular observing patterns like that of a satellite. In this steady state, the gains are constants in time, and thus could conceivably be computed off-line. These steady-state Kalman gains (i.e., Wiener gains) would yield optimal performance without the computational burden of true Kalman filtering. We proposed to use this type of constant-in-time Wiener gain for the assimilation of data from PMIRR and Mars Observer.

  20. Psychosocial working conditions and weight gain among employees.

    PubMed

    Lallukka, T; Laaksonen, M; Martikainen, P; Sarlio-Lähteenkorva, S; Lahelma, E

    2005-08-01

    To study the associations between psychosocial working conditions and weight gain. Data from postal questionnaires (response rate 67%) sent to 40- to 60-y-old women (n=7093) and men (n=1799) employed by the City of Helsinki in 2000-2002 were analysed. Weight gain during the previous 12 months was the outcome variable in logistic regression analyses. Independent variables included Karasek's job demands and job control, work fatigue, working overtime, work-related mental strain, social support and the work-home interface. The final models were adjusted for age, education, marital status, physical strain and body mass index. In the previous 12 months, 25% of women and 19% of men reported weight gain. Work fatigue and working overtime were associated with weight gain in both sexes. Women who were dissatisfied with combining paid work and family life were more likely to have gained weight. Men with low job demands were less likely to have gained weight. All of these associations were independent of each other. Few work-related factors were associated with weight gain. However, our study suggests that work fatigue and working overtime are potential risk factors for weight gain. These findings need to be confirmed in prospective studies.

  1. 30 CFR 75.703-2 - Approved grounding mediums.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Approved grounding mediums. 75.703-2 Section 75... mediums. For purposes of grounding offtrack direct-current machines, the following grounding mediums are... alternating current grounding medium where such machines are fed by an ungrounded direct-current power system...

  2. 30 CFR 75.703-2 - Approved grounding mediums.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Approved grounding mediums. 75.703-2 Section 75... mediums. For purposes of grounding offtrack direct-current machines, the following grounding mediums are... alternating current grounding medium where such machines are fed by an ungrounded direct-current power system...

  3. 30 CFR 75.703-2 - Approved grounding mediums.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Approved grounding mediums. 75.703-2 Section 75... mediums. For purposes of grounding offtrack direct-current machines, the following grounding mediums are... alternating current grounding medium where such machines are fed by an ungrounded direct-current power system...

  4. 30 CFR 75.703-2 - Approved grounding mediums.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Approved grounding mediums. 75.703-2 Section 75... mediums. For purposes of grounding offtrack direct-current machines, the following grounding mediums are... alternating current grounding medium where such machines are fed by an ungrounded direct-current power system...

  5. 30 CFR 75.703-2 - Approved grounding mediums.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Approved grounding mediums. 75.703-2 Section 75... mediums. For purposes of grounding offtrack direct-current machines, the following grounding mediums are... alternating current grounding medium where such machines are fed by an ungrounded direct-current power system...

  6. Time course of motor gains induced by music-supported therapy after stroke: An exploratory case study.

    PubMed

    Grau-Sánchez, Jennifer; Ramos, Neus; Duarte, Esther; Särkämö, Teppo; Rodríguez-Fornells, Antoni

    2017-09-01

    Previous studies have shown that Music-Supported Therapy (MST) can improve the motor function and promote functional neuroplastic changes in motor areas; however, the time course of motor gains across MST sessions and treatment periods remain unknown. The aim of this study was to explore the progression of the rehabilitation of motor deficits in a chronic stroke patient for a period of 7 months. A reversal design (ABAB) was implemented in a chronic stroke patient where no treatment was provided in the A periods and MST was applied in the B periods. Each period comprised of 4 weeks and an extensive evaluation of the motor function using clinical motor tests and 3D movement analysis was performed weekly. During the MST periods, a keyboard task was recorded daily. A follow-up evaluation was performed 3 months after the second MST treatment. Improvements were observed during the first sessions in the keyboard task but clinical gains were noticeable only at the end of the first treatment and during the second treatment period. These gains were maintained in the follow-up evaluation. This is the first study examining the pattern of motor recovery progression in MST, evidencing that gradual and continuous motor improvements are possible with the repeated application of MST training. Fast-acquisition in specific motor abilities was observed at the beginning of the MST training but generalization of these improvements to other motor tasks took place at the end or when another treatment period was provided. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  7. Effects of internal gain assumptions in building energy calculations

    NASA Astrophysics Data System (ADS)

    Christensen, C.; Perkins, R.

    1981-01-01

    The utilization of direct solar gains in buildings can be affected by operating profiles, such as schedules for internal gains, thermostat controls, and ventilation rates. Building energy analysis methods use various assumptions about these profiles. The effects of typical internal gain assumptions in energy calculations are described. Heating and cooling loads from simulations using the DOE 2.1 computer code are compared for various internal gain inputs: typical hourly profiles, constant average profiles, and zero gain profiles. Prototype single-family-detached and multifamily-attached residential units are studied with various levels of insulation and infiltration. Small detached commercial buildings and attached zones in large commercial buildings are studied with various levels of internal gains. The results indicate that calculations of annual heating and cooling loads are sensitive to internal gains, but in most cases are relatively insensitive to hourly variations in internal gains.

  8. Supplementation of CHROMagar Candida Medium with Pal's Medium for Rapid Identification of Candida dubliniensis

    PubMed Central

    Sahand, Ismail H.; Moragues, María D.; Eraso, Elena; Villar-Vidal, María; Quindós, Guillermo; Pontón, José

    2005-01-01

    CHROMagar Candida medium is used for the isolation and identification of Candida species, but it does not differentiate Candida albicans from Candida dubliniensis. This differentiation can be achieved by using Pal's agar, which cannot be used in primary isolation. We have combined both media to obtain a new medium that can be used for the isolation and identification of C. dubliniensis in primary cultures. PMID:16272515

  9. Correcting the Normalized Gain for Guessing

    ERIC Educational Resources Information Center

    Stewart, John; Stewart, Gay

    2010-01-01

    The normalized gain, "g", has been an important tool for the characterization of conceptual improvement in physics courses since its use in Hake's extensive study on conceptual learning in introductory physics. The normalized gain is calculated from the score on a pre-test administered before instruction and a post-test administered…

  10. 21 CFR 864.8500 - Lymphocyte separation medium.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Lymphocyte separation medium. 864.8500 Section 864.8500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... medium. (a) Identification. A lymphocyte separation medium is a device used to isolate lymphocytes from...

  11. 21 CFR 864.8500 - Lymphocyte separation medium.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Lymphocyte separation medium. 864.8500 Section 864.8500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... medium. (a) Identification. A lymphocyte separation medium is a device used to isolate lymphocytes from...

  12. 21 CFR 864.8500 - Lymphocyte separation medium.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Lymphocyte separation medium. 864.8500 Section 864.8500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... medium. (a) Identification. A lymphocyte separation medium is a device used to isolate lymphocytes from...

  13. 21 CFR 864.8500 - Lymphocyte separation medium.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Lymphocyte separation medium. 864.8500 Section 864.8500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... medium. (a) Identification. A lymphocyte separation medium is a device used to isolate lymphocytes from...

  14. 21 CFR 864.8500 - Lymphocyte separation medium.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Lymphocyte separation medium. 864.8500 Section 864.8500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... medium. (a) Identification. A lymphocyte separation medium is a device used to isolate lymphocytes from...

  15. Nucleus accumbens response to gains in reputation for the self relative to gains for others predicts social media use

    PubMed Central

    Meshi, Dar; Morawetz, Carmen; Heekeren, Hauke R.

    2013-01-01

    Our reputation is important to us; we've experienced natural selection to care about our reputation. Recently, the neural processing of gains in reputation (positive social feedback concerning one's character) has been shown to occur in the human ventral striatum. It is still unclear, however, how individual differences in the processing of gains in reputation may lead to individual differences in real-world behavior. For example, in the real-world, one way that people currently maintain their reputation is by using social media websites, like Facebook. Furthermore, Facebook use consists of a social comparison component, where users observe others' behavior and can compare it to their own. Therefore, we hypothesized a relationship between the way the brain processes specifically self-relevant gains in reputation and one's degree of Facebook use. We recorded functional neuroimaging data while participants received gains in reputation, observed the gains in reputation of another person, or received monetary reward. We demonstrate that across participants, when responding to gains in reputation for the self, relative to observing gains for others, reward-related activity in the left nucleus accumbens predicts Facebook use. However, nucleus accumbens activity in response to monetary reward did not predict Facebook use. Finally, a control step-wise regression analysis showed that Facebook use primarily explains our results in the nucleus accumbens. Overall, our results demonstrate how individual sensitivity of the nucleus accumbens to the receipt of self-relevant social information leads to differences in real-world behavior. PMID:24009567

  16. Nucleus accumbens response to gains in reputation for the self relative to gains for others predicts social media use.

    PubMed

    Meshi, Dar; Morawetz, Carmen; Heekeren, Hauke R

    2013-01-01

    Our reputation is important to us; we've experienced natural selection to care about our reputation. Recently, the neural processing of gains in reputation (positive social feedback concerning one's character) has been shown to occur in the human ventral striatum. It is still unclear, however, how individual differences in the processing of gains in reputation may lead to individual differences in real-world behavior. For example, in the real-world, one way that people currently maintain their reputation is by using social media websites, like Facebook. Furthermore, Facebook use consists of a social comparison component, where users observe others' behavior and can compare it to their own. Therefore, we hypothesized a relationship between the way the brain processes specifically self-relevant gains in reputation and one's degree of Facebook use. We recorded functional neuroimaging data while participants received gains in reputation, observed the gains in reputation of another person, or received monetary reward. We demonstrate that across participants, when responding to gains in reputation for the self, relative to observing gains for others, reward-related activity in the left nucleus accumbens predicts Facebook use. However, nucleus accumbens activity in response to monetary reward did not predict Facebook use. Finally, a control step-wise regression analysis showed that Facebook use primarily explains our results in the nucleus accumbens. Overall, our results demonstrate how individual sensitivity of the nucleus accumbens to the receipt of self-relevant social information leads to differences in real-world behavior.

  17. Energy storage systems having an electrode comprising Li.sub.xS.sub.y

    DOEpatents

    Xiao, Jie; Zhang, Jiguang; Graff, Gordon L.; Liu, Jun; Wang, Wei; Zheng, Jianming; Xu, Wu; Shao, Yuyan; Yang, Zhenguo

    2016-08-02

    Improved lithium-sulfur energy storage systems can utilizes Li.sub.xS.sub.y as a component in an electrode of the system. For example, the energy storage system can include a first electrode current collector, a second electrode current collector, and an ion-permeable separator separating the first and second electrode current collectors. A second electrode is arranged between the second electrode current collector and the separator. A first electrode is arranged between the first electrode current collector and the separator and comprises a first condensed-phase fluid comprising Li.sub.xS.sub.y. The energy storage system can be arranged such that the first electrode functions as a positive or a negative electrode.

  18. Lateral acoustic wave resonator comprising a suspended membrane of low damping resonator material

    DOEpatents

    Olsson, Roy H.; El-Kady; , Ihab F.; Ziaei-Moayyed, Maryam; Branch; , Darren W.; Su; Mehmet F.,; Reinke; Charles M.,

    2013-09-03

    A very high-Q, low insertion loss resonator can be achieved by storing many overtone cycles of a lateral acoustic wave (i.e., Lamb wave) in a lithographically defined suspended membrane comprising a low damping resonator material, such as silicon carbide. The high-Q resonator can sets up a Fabry-Perot cavity in a low-damping resonator material using high-reflectivity acoustic end mirrors, which can comprise phononic crystals. The lateral overtone acoustic wave resonator can be electrically transduced by piezoelectric couplers. The resonator Q can be increased without increasing the impedance or insertion loss by storing many cycles or wavelengths in the high-Q resonator material, with much lower damping than the piezoelectric transducer material.

  19. 21 CFR 133.103 - Asiago medium cheese.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Asiago medium cheese. 133.103 Section 133.103 Food... HUMAN CONSUMPTION CHEESES AND RELATED CHEESE PRODUCTS Requirements for Specific Standardized Cheese and Related Products § 133.103 Asiago medium cheese. Asiago medium cheese conforms to the definition and...

  20. 21 CFR 133.103 - Asiago medium cheese.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Asiago medium cheese. 133.103 Section 133.103 Food... HUMAN CONSUMPTION CHEESES AND RELATED CHEESE PRODUCTS Requirements for Specific Standardized Cheese and Related Products § 133.103 Asiago medium cheese. Asiago medium cheese conforms to the definition and...

  1. 20 CFR 220.141 - Substantial gainful activity, defined.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) Substantial work activity. Substantial work activity is work activity that involves doing significant physical... 20 Employees' Benefits 1 2011-04-01 2011-04-01 false Substantial gainful activity, defined. 220... RETIREMENT ACT DETERMINING DISABILITY Substantial Gainful Activity § 220.141 Substantial gainful activity...

  2. 20 CFR 220.141 - Substantial gainful activity, defined.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) Substantial work activity. Substantial work activity is work activity that involves doing significant physical... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Substantial gainful activity, defined. 220... RETIREMENT ACT DETERMINING DISABILITY Substantial Gainful Activity § 220.141 Substantial gainful activity...

  3. Complying with physician gain-sharing restrictions.

    PubMed

    O'Hare, P K

    1998-05-01

    Many IDSs are considering implementing gain-sharing programs as a way to motivate their physicians to provide high-quality, cost-effective services. Before embarking on such programs, however, IDSs need to understand the legal requirements associated with such programs to ensure that the gain-sharing arrangement is in compliance with Federal law.

  4. Medium chain triglycerides and hepatic encephalopathy

    PubMed Central

    Morgan, M. Hilary; Bolton, C. H.; Morris, J. S.; Read, A. E.

    1974-01-01

    The oral administration of short (C6) and medium (C8 and (C10) chain triglycerides produced no clinical or electroencephalographic changes in patients with cirrhosis of the liver. Arterial ammonia levels were also monitored in these patients and showed no significant change after medium chain triglycerides. It was concluded that medium chain triglycerides, known to be of potential value in the treatment of malabsorption in patients with cirrhosis, are not clinically contraindicated, even in patients with evidence of hepatic encephalopathy. PMID:4841275

  5. Radiation hardness of thin Low Gain Avalanche Detectors

    NASA Astrophysics Data System (ADS)

    Kramberger, G.; Carulla, M.; Cavallaro, E.; Cindro, V.; Flores, D.; Galloway, Z.; Grinstein, S.; Hidalgo, S.; Fadeyev, V.; Lange, J.; Mandić, I.; Medin, G.; Merlos, A.; McKinney-Martinez, F.; Mikuž, M.; Quirion, D.; Pellegrini, G.; Petek, M.; Sadrozinski, H. F.-W.; Seiden, A.; Zavrtanik, M.

    2018-05-01

    Low Gain Avalanche Detectors (LGAD) are based on a n++-p+-p-p++ structure where an appropriate doping of the multiplication layer (p+) leads to high enough electric fields for impact ionization. Gain factors of few tens in charge significantly improve the resolution of timing measurements, particularly for thin detectors, where the timing performance was shown to be limited by Landau fluctuations. The main obstacle for their operation is the decrease of gain with irradiation, attributed to effective acceptor removal in the gain layer. Sets of thin sensors were produced by two different producers on different substrates, with different gain layer doping profiles and thicknesses (45, 50 and 80 μm). Their performance in terms of gain/collected charge and leakage current was compared before and after irradiation with neutrons and pions up to the equivalent fluences of 5 ṡ 1015 cm-2. Transient Current Technique and charge collection measurements with LHC speed electronics were employed to characterize the detectors. The thin LGAD sensors were shown to perform much better than sensors of standard thickness (∼300 μm) and offer larger charge collection with respect to detectors without gain layer for fluences < 2 ṡ 1015 cm-2. Larger initial gain prolongs the beneficial performance of LGADs. Pions were found to be more damaging than neutrons at the same equivalent fluence, while no significant difference was found between different producers. At very high fluences and bias voltages the gain appears due to deep acceptors in the bulk, hence also in thin standard detectors.

  6. Effect of body image on pregnancy weight gain.

    PubMed

    Mehta, Ushma J; Siega-Riz, Anna Maria; Herring, Amy H

    2011-04-01

    The majority of women gain more weight during pregnancy than what is recommended. Since gestational weight gain is related to short and long-term maternal health outcomes, it is important to identify women at greater risk of not adhering to guidelines. The objective of this study was to examine the relationship between body image and gestational weight gain. The Body Image Assessment for Obesity tool was used to measure ideal and current body sizes in 1,192 women participating in the Pregnancy, Infection and Nutrition Study. Descriptive and multivariable techniques were used to assess the effects of ideal body size and discrepancy score (current-ideal body sizes), which reflected the level of body dissatisfaction, on gestational weight gain. Women who preferred to be thinner had increased risk of excessive gain if they started the pregnancy at a BMI ≤26 kg/m(2) but a decreased risk if they were overweight or obese. Comparing those who preferred thin body silhouettes to those who preferred average size silhouettes, low income women had increased risk of inadequate weight gain [RR = 1.76 (1.08, 2.88)] while those with lower education were at risk of excessive gain [RR = 1.11 (1.00, 1.22)]. Our results revealed that body image was associated with gestational weight gain but the relationship is complex. Identifying factors that affect whether certain women are at greater risk of gaining outside of guidelines may improve our ability to decrease pregnancy-related health problems.

  7. Brillouin gain enhancement in nano-scale photonic waveguide

    NASA Astrophysics Data System (ADS)

    Nouri Jouybari, Soodabeh

    2018-05-01

    The enhancement of stimulated Brillouin scattering in nano-scale waveguides has a great contribution in the improvement of the photonic devices technology. The key factors in Brillouin gain are the electrostriction force and radiation pressure generated by optical waves in the waveguide. In this article, we have proposed a new scheme of nano-scale waveguide in which the Brillouin gain is considerably improved compared to the previously-reported schemes. The role of radiation pressure in the Brillouin gain was much higher than the role of the electrostriction force. The Brillouin gain strongly depends on the structural parameters of the waveguide and the maximum value of 12127 W-1 m-1 is obtained for the Brillouin gain.

  8. A variable-gain output feedback control design methodology

    NASA Technical Reports Server (NTRS)

    Halyo, Nesim; Moerder, Daniel D.; Broussard, John R.; Taylor, Deborah B.

    1989-01-01

    A digital control system design technique is developed in which the control system gain matrix varies with the plant operating point parameters. The design technique is obtained by formulating the problem as an optimal stochastic output feedback control law with variable gains. This approach provides a control theory framework within which the operating range of a control law can be significantly extended. Furthermore, the approach avoids the major shortcomings of the conventional gain-scheduling techniques. The optimal variable gain output feedback control problem is solved by embedding the Multi-Configuration Control (MCC) problem, previously solved at ICS. An algorithm to compute the optimal variable gain output feedback control gain matrices is developed. The algorithm is a modified version of the MCC algorithm improved so as to handle the large dimensionality which arises particularly in variable-gain control problems. The design methodology developed is applied to a reconfigurable aircraft control problem. A variable-gain output feedback control problem was formulated to design a flight control law for an AFTI F-16 aircraft which can automatically reconfigure its control strategy to accommodate failures in the horizontal tail control surface. Simulations of the closed-loop reconfigurable system show that the approach produces a control design which can accommodate such failures with relative ease. The technique can be applied to many other problems including sensor failure accommodation, mode switching control laws and super agility.

  9. 21 CFR 133.103 - Asiago medium cheese.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Asiago medium cheese. 133.103 Section 133.103 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Related Products § 133.103 Asiago medium cheese. Asiago medium cheese conforms to the definition and...

  10. 21 CFR 133.103 - Asiago medium cheese.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Asiago medium cheese. 133.103 Section 133.103 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Related Products § 133.103 Asiago medium cheese. Asiago medium cheese conforms to the definition and...

  11. 21 CFR 133.103 - Asiago medium cheese.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Asiago medium cheese. 133.103 Section 133.103 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Related Products § 133.103 Asiago medium cheese. Asiago medium cheese conforms to the definition and...

  12. Probing the mechanisms of drug release from amorphous solid dispersions in medium-soluble and medium-insoluble carriers.

    PubMed

    Sun, Dajun D; Lee, Ping I

    2015-08-10

    The objective of the current study is to mechanistically differentiate the dissolution and supersaturation behaviors of amorphous drugs from amorphous solid dispersions (ASDs) based on medium-soluble versus medium-insoluble carriers under nonsink dissolution conditions through a direct head-to-head comparison. ASDs of indomethacin (IND) were prepared in several polymers which exhibit different solubility behaviors in acidic (pH1.2) and basic (pH7.4) dissolution media. The selected polymers range from water-soluble (e.g., PVP and Soluplus) and water-insoluble (e.g., ethylcellulose and Eudragit RL PO) to those only soluble in an acidic or basic dissolution medium (e.g., Eudragit E100, Eudragit L100, and HPMCAS). At 20wt.% drug loading, DSC and powder XRD analysis confirmed that the majority of incorporated IND was present in an amorphous state. Our nonsink dissolution results confirm that whether the carrier matrix is medium soluble determines the release mechanism of amorphous drugs from ASD systems which has a direct impact on the rate of supersaturation generation, thus in turn affecting the evolution of supersaturation in amorphous systems. For example, under nonsink dissolution conditions, the release of amorphous IND from medium-soluble carriers is governed by a dissolution-controlled mechanism leading to an initial surge of supersaturation followed by a sharp decline in drug concentration due to rapid nucleation and crystallization. In contrast, the dissolution of IND ASD from medium-insoluble carriers is more gradual as drug release is regulated by a diffusion-controlled mechanism by which drug supersaturation is built up gradually and sustained over an extended period of time without any apparent decline. Since several tested carrier polymers can be switched from soluble to insoluble by simply changing the pH of the dissolution medium, the results obtained here provide unequivocal evidence of the proposed transition of kinetic solubility profiles from the

  13. 49 CFR 236.811 - Speed, medium.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Speed, medium. 236.811 Section 236.811 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Speed, medium. A speed not exceeding 40 miles per hour. ...

  14. 49 CFR 236.811 - Speed, medium.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Speed, medium. 236.811 Section 236.811 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Speed, medium. A speed not exceeding 40 miles per hour. ...

  15. 49 CFR 236.811 - Speed, medium.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Speed, medium. 236.811 Section 236.811 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Speed, medium. A speed not exceeding 40 miles per hour. ...

  16. 49 CFR 236.811 - Speed, medium.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Speed, medium. 236.811 Section 236.811 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Speed, medium. A speed not exceeding 40 miles per hour. ...

  17. 49 CFR 236.811 - Speed, medium.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Speed, medium. 236.811 Section 236.811 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Speed, medium. A speed not exceeding 40 miles per hour. ...

  18. 24 CFR 3280.506 - Heat loss/heat gain.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Heat loss/heat gain. 3280.506... URBAN DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.506 Heat loss/heat gain. The manufactured home heat loss/heat gain shall be determined by methods outlined in...

  19. 24 CFR 3280.506 - Heat loss/heat gain.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Heat loss/heat gain. 3280.506... URBAN DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.506 Heat loss/heat gain. The manufactured home heat loss/heat gain shall be determined by methods outlined in...

  20. 24 CFR 3280.506 - Heat loss/heat gain.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Heat loss/heat gain. 3280.506... URBAN DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.506 Heat loss/heat gain. The manufactured home heat loss/heat gain shall be determined by methods outlined in...

  1. 24 CFR 3280.506 - Heat loss/heat gain.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 5 2014-04-01 2014-04-01 false Heat loss/heat gain. 3280.506... URBAN DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.506 Heat loss/heat gain. The manufactured home heat loss/heat gain shall be determined by methods outlined in...

  2. 24 CFR 3280.506 - Heat loss/heat gain.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Heat loss/heat gain. 3280.506... URBAN DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.506 Heat loss/heat gain. The manufactured home heat loss/heat gain shall be determined by methods outlined in...

  3. Optical properties of nanowire metamaterials with gain

    NASA Astrophysics Data System (ADS)

    Lima, Joaquim; Adam, Jost; Rego, Davi; Esquerre, Vitaly; Bordo, Vladimir

    2016-11-01

    The transmittance, reflectance and absorption of a nanowire metamaterial with optical gain are numerically simulated and investigated. It is assumed that the metamaterial is represented by aligned silver nanowires embedded into a semiconductor matrix, made of either silicon or gallium phosphide. The gain in the matrix is modeled by adding a negative imaginary part to the dielectric function of the semiconductor. It is found that the optical coefficients of the metamaterial depend on the gain magnitude in a non-trivial way: they can both increase and decrease with gain depending on the lattice constant of the metamaterial. This peculiar behavior is explained by the field redistribution between the lossy metal nanowires and the amplifying matrix material. These findings are significant for a proper design of nanowire metamaterials with low optical losses for diverse applications.

  4. New Discovery About Middle-Age Weight Gain

    MedlinePlus

    ... Middle-Age Weight Gain Follow us Photo: AdobeStock New Discovery About Middle-Age Weight Gain A TEAM ... findings could lead to the development of a new type of weight-loss medication. SOURCE: NIH Research ...

  5. Weight gain in women diagnosed with breast cancer.

    PubMed

    Demark-Wahnefried, W; Rimer, B K; Winer, E P

    1997-05-01

    This review of the literature indicates that weight gain is a common observation among women after the diagnosis of breast cancer. Gains in weight range from 0 to 50 lb and are influenced by menopausal status; nodal status; and the type, duration, and intensity of treatment. Weight gain appears to be greater among premenopausal women; among those who are node positive; and among those receiving higher dose, longer duration, and multiagent regimens. Psychosocial research suggests that weight gain has a profoundly negative impact on quality of life in patients with breast cancer. Recent findings also suggest that weight gain during therapy may increase the risk of recurrence and decrease survival. Although weight gain in patients with breast cancer is clinically well appreciated, little research has been conducted to investigate the underlying mechanisms of energy imbalance. Changes in rates of metabolism, physical activity, and dietary intake are all plausible mechanisms and call for more research. Further study will provide valuable insight into the problem of weight gain and encourage effective interventions to improve the quality and quantity of life for the woman with breast cancer. Until more is known, however, dietetics practitioners will have to monitor and work individually with patients with breast cancer and use empirical approaches to achieve the important goal of weight management.

  6. Gain Shift Corrections at Chi-Nu

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brown, Tristan Brooks; Devlin, Matthew James

    Ambient conditions have the potential to cause changes in liquid scintillator detector gain that vary with time and temperature. These gain shifts can lead to poor resolution in both energy as well as pulse shape discrimination. In order to correct for these shifts in the Chi-Nu high energy array, a laser system has been developed for calibration of the pulse height signals.

  7. Method for increasing the rate of compressive strength gain in hardenable mixtures containing fly ash

    DOEpatents

    Liskowitz, John W.; Wecharatana, Methi; Jaturapitakkul, Chai; Cerkanowicz, deceased, Anthony E.

    1997-01-01

    The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction. The invention provides a method for increasing the rate of strength gain of a hardenable mixture containing fly ash by exposing the fly ash to an aqueous slurry of calcium oxide (lime) prior to its incorporation into the hardenable mixture. The invention further relates to such hardenable mixtures, e.g., concrete and mortar, that contain fly ash pre-reacted with calcium oxide. In particular, the fly ash is added to a slurry of calcium oxide in water, prior to incorporating the fly ash in a hardenable mixture. The hardenable mixture may be concrete or mortar. In a specific embodiment, mortar containing fly ash treated by exposure to an aqueous lime slurry are prepared and tested for compressive strength at early time points.

  8. Methods of forming aluminum oxynitride-comprising bodies, including methods of forming a sheet of transparent armor

    DOEpatents

    Chu, Henry Shiu-Hung [Idaho Falls, ID; Lillo, Thomas Martin [Idaho Falls, ID

    2008-12-02

    The invention includes methods of forming an aluminum oxynitride-comprising body. For example, a mixture is formed which comprises A:B:C in a respective molar ratio in the range of 9:3.6-6.2:0.1-1.1, where "A" is Al.sub.2O.sub.3, "B" is AlN, and "C" is a total of one or more of B.sub.2O.sub.3, SiO.sub.2, Si--Al--O--N, and TiO.sub.2. The mixture is sintered at a temperature of at least 1,600.degree. C. at a pressure of no greater than 500 psia effective to form an aluminum oxynitride-comprising body which is at least internally transparent and has at least 99% maximum theoretical density.

  9. Gains in accuracy from averaging ratings of abnormality

    NASA Astrophysics Data System (ADS)

    Swensson, Richard G.; King, Jill L.; Gur, David; Good, Walter F.

    1999-05-01

    Six radiologists used continuous scales to rate 529 chest-film cases for likelihood of five separate types of abnormalities (interstitial disease, nodules, pneumothorax, alveolar infiltrates and rib fractures) in each of six replicated readings, yielding 36 separate ratings of each case for the five abnormalities. Analyses for each type of abnormality estimated the relative gains in accuracy (area below the ROC curve) obtained by averaging the case-ratings across: (1) six independent replications by each reader (30% gain), (2) six different readers within each replication (39% gain) or (3) all 36 readings (58% gain). Although accuracy differed among both readers and abnormalities, ROC curves for the median ratings showed similar relative gains in accuracy. From a latent-variable model for these gains, we estimate that about 51% of a reader's total decision variance consisted of random (within-reader) errors that were uncorrelated between replications, another 14% came from that reader's consistent (but idiosyncratic) responses to different cases, and only about 35% could be attributed to systematic variations among the sampled cases that were consistent across different readers.

  10. The Role of Morphology and Electronic Chain Aggregation on the Optical Gain Properties of Semiconducting Conjugated Polymers

    NASA Astrophysics Data System (ADS)

    Lampert, Zachary Evan

    thresholds and large net gains are highly desirable. In this thesis, we also discuss novel routes we developed for enhancement of ASE performance in MEH-PPV thin film planar waveguides. The first technique relied on improving the distribution of the TE0 guided mode in the CP gain layer through optimization of waveguide architecture. This was achieved by fabricating symmetric heterostructure waveguides formed from a core layer of MEH-PPV sandwiched between an SiO2 buffer and index matched poly(methyl methacrylate) (PMMA) cover layer. Relative to asymmetric waveguides of Si(100)/SiO2/MEH-PPV/Air, symmetric waveguides exhibited increased optical confinement and reduced propagation loss enabling lower ASE threshold (40%) and higher net gain (50%). Independent of device architecture and degree of aggregation in the films, we discovered that optical gain is also highly dependent on the excitation conditions, specifically the temporal width of the pump laser pulses. A 400% increase in net gain was achieved under transient (25 picosecond pulses), compared to quasi-steady state (8 nanosecond pulses), excitation conditions. This large difference is attributed to low pumping efficiency and increased non-radiative recombination under ns pumping, which reduces the emission cross-section resulting in a net decrease in gain. The gain values we achieved in the ps regime are to the best of our knowledge the largest gain values reported to date for thin conjugated polymer films measured using the variable stripe length (VSL) technique. Films pumped in the transient regime also required 30 times less pump energy density to reach threshold in comparison with films pumped in the quasi-steady state regime, although the excited state densities were essentially the same. These results demonstrate that the pumping efficiency, and hence generation rate of excited states in a gain medium, can be dramatically increased by using pump laser pulses that are shorter than the exciton luminescence lifetime

  11. Determination of optimized growth medium and cryoprotective additives to enhance the growth and survival of Lactobacillus salivarius.

    PubMed

    Yeo, Soyoung; Shin, Hee Sung; Lee, Hye Won; Hong, Doseon; Park, Hyunjoon; Holzapfel, Wilhelm; Kim, Eun Bae; Huh, Chul Sung

    2018-03-16

    Beneficial effects of lactic acid bacteria (LAB) have been intensively investigated in recent decades with special focus on modulation of the host intestinal microbiota. Numerous discoveries of effective probiotics are driven by a significantly increasing demand for dietary supplements. Consequently, technological advances in the large-scale production and lyophilization are needed by probiotic-related industries for producing probiotic LAB for commercial use. Our study had a dual objective, i.e., to determine the optimum growth medium composition and to investigate appropriate cryoprotective additives (CPAs) for Lactobacillus salivarius , and compare its responses with other Lactobacillus species. The one-factor-at-a-time method and central composite design were applied to determine the optimal medium composition for L. salivarius cultivation. The following composition of the medium was established (per liter): 21.64 g maltose, 85 g yeast extract, 1.21 ml Tween 80, 6 g sodium acetate, 0.2 g MgSO 4 ∙7H 2 O, 0.02 g MnSO 4 ∙H 2 O, 1 g K 2 HPO 4 , 1.5 g KH 2 PO 4 , 0.01 g FeSO 4 ∙7H 2 O and 1 g sodium citrate. A cryoprotective additive combination comprising 10% ( w/v ) skim milk and 10% ( w/v ) sucrose supplemented with 2.5% ( w/v ) sodium glutamate was selected for L. salivarius , and its effectiveness was confirmed using culture-independent methods in the freeze-dried cells of the Lactobacillus strains. In conclusion, the optimized medium enhanced the species-specific cultivation of L. salivarius . On the other hand, the cryoprotective effects of the selected CPA mixture may also be dependent on the bacterial strain. This study highlights the necessity for precise and advanced processing techniques for large-scale production of probiotics in the food and feed industries.

  12. Sudden gains in exposure therapy for obsessive-compulsive disorder.

    PubMed

    Collins, Lindsey M; Coles, Meredith E

    2017-06-01

    Prior research in the treatment of depression and anxiety has demonstrated that a sudden reduction in symptoms between two consecutive sessions (sudden gain) is related to lower post-treatment symptom severity (e.g. Hofmann, Schulz, Meuret, Moscovitch, & Suvak, 2006; Tang & DeRubeis, 1999). However, only one study has examined sudden gains in the treatment of obsessive compulsive disorder (OCD). In that study, one-third of the patients with OCD experienced a sudden gain (Aderka et al., 2012). Further, patients who had a sudden gain had lower clinician-rated OCD symptom severity post-treatment (Aderka et al., 2012). In replication, the current study examined the frequency, characteristics, and clinical impact of sudden gains in 27 OCD patients during exposure and response prevention (ERP) therapy. Fifty two percent of patients experienced a sudden gain. The mean magnitude of a sudden gain represented, on average, 61.4% of total symptom reduction. Following treatment, individuals who had experienced a sudden gain were rated as less severe on the clinical global impression scale, but they did not experience a greater reduction in OCD symptoms (pre-to post-treatment) than those without a sudden gain. None of the pre-treatment characteristics tested were found to significantly predict whether a patient would have a sudden gain. Additional research examining predictors of, and patterns of, change in OCD symptoms is warranted. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Potential gains from hospital mergers in Denmark.

    PubMed

    Kristensen, Troels; Bogetoft, Peter; Pedersen, Kjeld Moeller

    2010-12-01

    The Danish hospital sector faces a major rebuilding program to centralize activity in fewer and larger hospitals. We aim to conduct an efficiency analysis of hospitals and to estimate the potential cost savings from the planned hospital mergers. We use Data Envelopment Analysis (DEA) to estimate a cost frontier. Based on this analysis, we calculate an efficiency score for each hospital and estimate the potential gains from the proposed mergers by comparing individual efficiencies with the efficiency of the combined hospitals. Furthermore, we apply a decomposition algorithm to split merger gains into technical efficiency, size (scale) and harmony (mix) gains. The motivation for this decomposition is that some of the apparent merger gains may actually be available with less than a full-scale merger, e.g., by sharing best practices and reallocating certain resources and tasks. Our results suggest that many hospitals are technically inefficient, and the expected "best practice" hospitals are quite efficient. Also, some mergers do not seem to lower costs. This finding indicates that some merged hospitals become too large and therefore experience diseconomies of scale. Other mergers lead to considerable cost reductions; we find potential gains resulting from learning better practices and the exploitation of economies of scope. To ensure robustness, we conduct a sensitivity analysis using two alternative returns-to-scale assumptions and two alternative estimation approaches. We consistently find potential gains from improving the technical efficiency and the exploitation of economies of scope from mergers.

  14. Optomechanical transistor with mechanical gain

    NASA Astrophysics Data System (ADS)

    Zhang, X. Z.; Tian, Lin; Li, Yong

    2018-04-01

    We study an optomechanical transistor, where an input field can be transferred and amplified unidirectionally in a cyclic three-mode optomechanical system. In this system, the mechanical resonator is coupled simultaneously to two cavity modes. We show that it only requires a finite mechanical gain to achieve the nonreciprocal amplification. Here the nonreciprocity is caused by the phase difference between the linearized optomechanical couplings that breaks the time-reversal symmetry of this system. The amplification arises from the mechanical gain, which provides an effective phonon bath that pumps the mechanical mode coherently. This effect is analogous to the stimulated emission of atoms, where the probe field can be amplified when its frequency is in resonance with that of the anti-Stokes transition. We show that by choosing optimal parameters, this optomechanical transistor can reach perfect unidirectionality accompanied with strong amplification. In addition, the presence of the mechanical gain can result in ultralong delay in the phase of the probe field, which provides an alternative to controlling light transport in optomechanical systems.

  15. Symmetric Gain Optoelectronic Mixers for LADAR

    DTIC Science & Technology

    2008-12-01

    photodetector in the receiver is used as an optoelectronic mixer (OEM). Adding gain to the optoelectronic mixer allows the following transimpedance ...output is the low frequency difference signal, several orders of magnitude lower than the LO signal. Therefore, the gain of the transimpedance ... amplifier (TZA) following the photodetector can be increased, improving LADAR range. The metal-semiconductor- metal (MSM) Schottky detector is such a

  16. Surface plasmon-polariton propagation in piecewise linear chains of composite nanospheres: the role of optical gain and chain layout.

    PubMed

    Udagedara, Indika B; Rukhlenko, Ivan D; Premaratne, Malin

    2011-10-10

    The energy transport properties of plasmonic waveguides can be analyzed by solving the dispersion relation for surface plasmon-polaritons (SPPs). We use this approach to derive an approximate analytical expression for SPP propagation length when the waveguide is composed of linearly arranged metallic nanoparticles, while assuming that metal losses are small or partially compensated by gain. Applied to metal-dielectric (composite) nanospheres, the obtained expression allows us to optimize the performance of the waveguide and arrive at a number of practical design rules. Specifically, we show that SPP attenuation can be minimized at a certain interparticle distance for transverse modes, but gradually grows for both longitudinal and transverse modes with the increase of particle separation. We also show that the two basic methods of supplying gain to the system, i.e., embedding the particles into a gain medium or having a metal-gain composition for the particles, do not perform equally well and the former method is more efficient, but the way the two methods affect depends on the polarization of SPPs. To investigate the role of the nanoparticles' arrangement in determining SPP characteristics, we follow a purely numerical approach and consider a two-segment bent waveguide as an example. Analyzing the waveguide's transmission shows that it behaves in an oscillatory manner with respect to the angle between the two segments and is therefore higher for certain angles than for the others. This suggests that, in the design of waveguides with bends, careful attention needs to be paid in order to avoid bend angles that yield low transmission and to choose angles that give maximum transmission.

  17. Gain curves and hydrodynamic modeling for shock ignition

    NASA Astrophysics Data System (ADS)

    Lafon, M.; Ribeyre, X.; Schurtz, G.

    2010-05-01

    Ignition of a precompressed thermonuclear fuel by means of a converging shock is now considered as a credible scheme to obtain high gains for inertial fusion energy. This work aims at modeling the successive stages of the fuel time history, from compression to final thermonuclear combustion, in order to provide the gain curves of shock ignition (SI). The leading physical mechanism at work in SI is pressure amplification, at first by spherical convergence, and by collision with the shock reflected at center during the stagnation process. These two effects are analyzed, and ignition conditions are provided as functions of the shock pressure and implosion velocity. Ignition conditions are obtained from a non-isobaric fuel assembly, for which we present a gain model. The corresponding gain curves exhibit a significantly lower ignition threshold and higher target gains than conventional central ignition.

  18. Gestational Weight Gain: Association with Adverse Pregnancy Outcomes.

    PubMed

    Hannaford, Karen E; Tuuli, Methodius G; Odibo, Linda; Macones, George A; Odibo, Anthony O

    2017-01-01

    Background  It is unclear how adherence to the Institute of Medicine's (IOM) guidelines for weight gain affects pregnancy outcomes. Objective  We investigated how weight gain outside the IOM's recommendations affects the risks of adverse pregnancy outcomes. Study Design  We performed a secondary analysis of a prospective cohort study including singleton, nonanomalous fetuses. The risks of small for gestational age (SGA), macrosomia, preeclampsia, cesarean delivery, gestational diabetes, or preterm birth were calculated for patients who gained weight below or above the IOM's recommendations based on body mass index category. A time-to-event analysis was performed to account for gestational age at delivery. A Cox proportional model was fit to estimate hazard ratios accounting for possible confounders. Results  Women who gained weight below recommendations were 2.5 times more likely to deliver SGA and twice as likely to deliver preterm. Normal-weight patients who gained below recommendations were 2.5 times more likely to deliver SGA and twice as likely to deliver preterm. Obese patients who gained inadequate weight were 2.5 times more likely to deliver SGA. Conclusion  Among normal-weight patients, adhering to IOM recommendations may prevent growth abnormalities and preterm delivery. Among obese patients, a minimum weight gain requirement may prevent SGA infants. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  19. Antidepressants and Weight Gain

    MedlinePlus

    ... 2015;37:46. Blumenthal SR, et al. An electronic health records study of long-term weight gain following antidepressant ... your agreement to the Terms and Conditions and Privacy Policy linked below. Terms and Conditions Privacy Policy ...

  20. Sound pressure gain produced by the human middle ear.

    PubMed

    Kurokawa, H; Goode, R L

    1995-10-01

    The acoustic function of the middle ear is to match sound passing from the low impedance of air to the high impedance of cochlear fluid. Little information is available on the actual middle ear pressure gain in human beings. This article describes experiments on middle ear pressure gain in six fresh human temporal bones. Stapes footplate displacement and phase were measured with a laser Doppler vibrometer before and after removal of the tympanic membrane, malleus, and incus. Acoustic insulation of the round window with clay was performed. Umbo displacement was also measured before tympanic membrane removal to assess baseline tympanic membrane function. The middle ear has its major gain in the lower frequencies, with a peak near 0.9 kHz. The mean gain was 23.0 dB below 1.0 kHz, the resonant frequency of the middle ear; the mean peak gain was 26.6 dB. Above 1.0 kHz, the second pressure gain decreased at a rate of -8.6 dB/octave, with a mean gain of 6.5 dB at 4.0 kHz. Only a small amount of gain was present above 7.0 kHz. Significant individual differences in pressure gain were found between ears that appeared related to variations in tympanic membrane function and not to variations in cochlear impedance.

  1. Welfare Gains from Financial Liberalization

    PubMed Central

    Townsend, Robert M.; Ueda, Kenichi

    2010-01-01

    Financial liberalization has been a controversial issue, as empirical evidence for growth enhancing effects is mixed. Here, we find sizable welfare gains from liberalization (cost to repression), though the gain in economic growth is ambiguous. We take the view that financial liberalization is a government policy that alters the path of financial deepening, while financial deepening is endogenously chosen by agents given a policy and occurs in transition towards a distant steady state. This history-dependent view necessitates the use of simulation analysis based on a growth model. Our application is a specific episode: Thailand from 1976 to 1996. PMID:20806055

  2. Fracture and Medium Modeling, by Analizing Hidraulic Fracturing Induced Microseismicity

    NASA Astrophysics Data System (ADS)

    Gomez Alba, S.; Vargas Jiménez, C. A.

    2014-12-01

    Hydraulic fracturing is an essential technology for most unconventional hydrocarbon resources and many conventional ones as well. The primary limitation on the improvement and optimization of the fracturing process is the minimal access to observe the behavior of the fracture in the subsurface. Without direct observational evidence, hypothetical mechanisms must be assumed and then tested for their validity with indirect information such as wellbore measurements, indirect production and pressure behavior. One of the most important sources of information today is the relation made between micro seismic source mechanisms and fracture behavior. Hydraulic fractures induce some level of micro seismicity when the stress conditions in the Earth are altered by changes in stress during the operations. The result is the sudden movement between rock elements and the radiation of both compressional and shear energy in a seismic range that can be detected and recorded with sensitive receivers. The objective of this work is to provide reasonable information when applying inversion methods in order to estimate the vertical and horizontal spatial heterogeneities in medium and energy radiation distribution of microseisms while fracking operations. The method consist in record microseisms at a previous lineal array of stations (triaxial accelerometers) which are located close to the source coordinates and cover the area of study. The analysis clarify some ideas about what information can be gained from the micro seismic source data and according to the obtained results, what kind of comparisons and associations might be done to evaluate the fracking performance operation. Non uniformities in medium such as faults would be revealed by interpreted scattering coefficients. Fracture properties like distance, velocity and orientation would be also determined by analyzing energy radiation.

  3. Small and medium power reactors 1987

    NASA Astrophysics Data System (ADS)

    1987-12-01

    This TECDOC follows the publication of TECDOC-347: Small and Medium Power Reactors (SMPR) Project Initiation Study, Phase 1, published in 1985 and TECDOC-376: Small and Medium Power Reactors 1985 published in 1986. It is mainly intended for decision makers in Developing Member States interested in embarking on a nuclear power program. It consists of two parts: (1) guidelines for the introduction of small and medium power reactors in developing countries. These Guidelines were established during the Advisory Group Meeting held in Vienna from 11 to 15 May 1987. Their purpose is to review key aspects relating to the introduction of small and medium power reactors in developing countries; (2) up-dated information on SMPR Concepts Contributed by Supplier Industries. According to the recommendations of the Second Technical Committee Meeting on SMPRs held in Vienna in March 1985, this part contains the up-dated information formerly published in Annex 1 of the above mentioned TECDOC-347.

  4. Antipsychotic induced weight gain in schizophrenia:mechanisms and management.

    PubMed

    Rege, Sanil

    2008-05-01

    The aim of the present paper was to describe the mechanisms and management of antipsychotic-induced weight gain in schizophrenia patients. A comprehensive literature review of all available articles on the mechanisms and management of antipsychotic-induced weight gain was done by searching databases PsychINFO and PubMed. A summary of the available guidelines for monitoring of antipsychotic-induced weight gain and metabolic syndrome is also provided. There has been a substantial increase in the number of studies investigating the mechanisms and management of antipsychotic-induced weight gain after 2002. These include advances in the understanding of pharmacogenomics of weight gain and several randomized controlled trials (RCTs) evaluating pharmacological and psychological treatments to promote weight loss. The most effective strategy for prevention of weight gain is the choice of antipsychotic medication with low weight gain potential. In individuals with established weight gain and metabolic issues, switching to an antipsychotic agent with lower weight gain potential and/or lifestyle modifications with physical activity are most effective in promoting weight loss. Pharmacological agents such as orlistat and sibutramine are effective in general obesity but have not been sufficiently evaluated in antipsychotic-induced weight gain. The case to prescribe routine pharmacological treatment to promote weight loss is weak. Long-term, pragmatic studies are required to inform clinical practice. Weight gain in schizophrenia is associated with significant physical and psychological morbidity. Achieving an optimal trade-off between effectiveness and side-effects of antipsychotic agents, although difficult, is achievable. This should be based on three main principles: (i) a shared decision-making model between the patient, clinician and carer(s) when choosing an antipsychotic; (ii) a commitment to baseline and follow-up monitoring with explicit identification of the responsible

  5. Broadband mixing of $${\\mathscr{P}}{\\mathscr{T}}$$-symmetric and $${\\mathscr{P}}{\\mathscr{T}}$$-broken phases in photonic heterostructures with a one-dimensional loss/gain bilayer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Özgün, Ege; Serebryannikov, Andriy E.; Ozbay, Ekmel

    Combining loss and gain components in one photonic heterostructure opens a new route to efficient manipulation by radiation, transmission, absorption, and scattering of electromagnetic waves. Therefore, loss/gain structures enablingmore » $${\\mathscr{P}}{\\mathscr{T}}$$-symmetric and $${\\mathscr{P}}{\\mathscr{T}}$$-broken phases for eigenvalues have extensively been studied in the last decade. In particular, translation from one phase to another, which occurs at the critical point in the two-channel structures with one-dimensional loss/gain components, is often associated with one-way transmission. In this report, broadband mixing of the $${\\mathscr{P}}{\\mathscr{T}}$$-symmetric and $${\\mathscr{P}}{\\mathscr{T}}$$-broken phases for eigenvalues is theoretically demonstrated in heterostructures with four channels obtained by combining a one-dimensional loss/gain bilayer and one or two thin polarization-converting components (PCCs). The broadband phase mixing in the four-channel case is expected to yield advanced transmission and absorption regimes. Various configurations are analyzed, which are distinguished in symmetry properties and polarization conversion regime of PCCs. The conditions necessary for phase mixing are then discussed. The simplest two-component configurations with broadband mixing are found, as well as the more complex three-component configurations wherein symmetric and broken sets are not yet mixed and appear in the neighbouring frequency ranges. Peculiarities of eigenvalue behaviour are considered for different permittivity ranges of loss/gain medium, i.e., from epsilon-near-zero to high-epsilon regime.« less

  6. Broadband mixing of $${\\mathscr{P}}{\\mathscr{T}}$$-symmetric and $${\\mathscr{P}}{\\mathscr{T}}$$-broken phases in photonic heterostructures with a one-dimensional loss/gain bilayer

    DOE PAGES

    Özgün, Ege; Serebryannikov, Andriy E.; Ozbay, Ekmel; ...

    2017-11-14

    Combining loss and gain components in one photonic heterostructure opens a new route to efficient manipulation by radiation, transmission, absorption, and scattering of electromagnetic waves. Therefore, loss/gain structures enablingmore » $${\\mathscr{P}}{\\mathscr{T}}$$-symmetric and $${\\mathscr{P}}{\\mathscr{T}}$$-broken phases for eigenvalues have extensively been studied in the last decade. In particular, translation from one phase to another, which occurs at the critical point in the two-channel structures with one-dimensional loss/gain components, is often associated with one-way transmission. In this report, broadband mixing of the $${\\mathscr{P}}{\\mathscr{T}}$$-symmetric and $${\\mathscr{P}}{\\mathscr{T}}$$-broken phases for eigenvalues is theoretically demonstrated in heterostructures with four channels obtained by combining a one-dimensional loss/gain bilayer and one or two thin polarization-converting components (PCCs). The broadband phase mixing in the four-channel case is expected to yield advanced transmission and absorption regimes. Various configurations are analyzed, which are distinguished in symmetry properties and polarization conversion regime of PCCs. The conditions necessary for phase mixing are then discussed. The simplest two-component configurations with broadband mixing are found, as well as the more complex three-component configurations wherein symmetric and broken sets are not yet mixed and appear in the neighbouring frequency ranges. Peculiarities of eigenvalue behaviour are considered for different permittivity ranges of loss/gain medium, i.e., from epsilon-near-zero to high-epsilon regime.« less

  7. Measurement of electrode-tissue interface impedance for improvement of a transcutaneous data transmission using human body as transmission medium.

    PubMed

    Okamoto, Eiji; Kato, Yoshikuni; Kikuchi, Sakiko; Mitamura, Yoshinori

    2014-01-01

    The electrical property between an electrode and skin or tissue is one of the important issues for communication performance of the transcutaneous communication system (TCS) using a human body as a conductive medium.In this study, we used a simple method to measure interface resistance between the electrode and skin on the surface of the body. The electrode-electrode impedance was measured by a commercially available LCR meter with changes in the distance between two electrodes on an arm of a healthy male subject, and we obtained the tissue resistivity and electrode-skin interface resistance using the cross-sectional area of the arm.We also measured transmission gain of the TCS on the surface of the body, and we investigated the relationship between electrode-skin interface resistance and transmission gain. We examined four kinds of electrodes: a stainless steel electrode, a titanium electrode, an Ag-AgCl electrode and an Ag-AgCl paste electrode. The stainless steel electrode, which had lower electrode-skin resistance, had higher transmission gain.The results indicate that an electrode that has lower electrode-skin resistance will contribute to improvement of the performance of the TCS and that electrode-skin interface resistance is one of valuable evaluation parameters for selecting an optimum electrode for the TCS.

  8. Extensive intron gain in the ancestor of placental mammals

    PubMed Central

    2011-01-01

    Background Genome-wide studies of intron dynamics in mammalian orthologous genes have found convincing evidence for loss of introns but very little for intron turnover. Similarly, large-scale analysis of intron dynamics in a few vertebrate genomes has identified only intron losses and no gains, indicating that intron gain is an extremely rare event in vertebrate evolution. These studies suggest that the intron-rich genomes of vertebrates do not allow intron gain. The aim of this study was to search for evidence of de novo intron gain in domesticated genes from an analysis of their exon/intron structures. Results A phylogenomic approach has been used to analyse all domesticated genes in mammals and chordates that originated from the coding parts of transposable elements. Gain of introns in domesticated genes has been reconstructed on well established mammalian, vertebrate and chordate phylogenies, and examined as to where and when the gain events occurred. The locations, sizes and amounts of de novo introns gained in the domesticated genes during the evolution of mammals and chordates has been analyzed. A significant amount of intron gain was found only in domesticated genes of placental mammals, where more than 70 cases were identified. De novo gained introns show clear positional bias, since they are distributed mainly in 5' UTR and coding regions, while 3' UTR introns are very rare. In the coding regions of some domesticated genes up to 8 de novo gained introns have been found. Intron densities in Eutheria-specific domesticated genes and in older domesticated genes that originated early in vertebrates are lower than those for normal mammalian and vertebrate genes. Surprisingly, the majority of intron gains have occurred in the ancestor of placentals. Conclusions This study provides the first evidence for numerous intron gains in the ancestor of placental mammals and demonstrates that adequate taxon sampling is crucial for reconstructing intron evolution. The

  9. A generalized predictive model for direct gain

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Givoni, B.

    In the correlational model for direct gain developed by the Los Alamos National Laboratory, a list of constants applicable to different types of buildings or passive solar systems was specified separately for each type. In its original form, the model was applicable only to buildings similar in their heat capacity, type of glazing, or night insulation to the types specified by the model. While maintaining the general form of the predictive equations, the new model, the predictive model for direct gain (PMDG), replaces the constants with functions dependent upon the thermal properties of the building, or the components of themore » solar system, or both. By this transformation, the LANL model for direct gain becomes a generalized one. The new model predicts the performance of buildings heated by direct gain with any heat capacity, glazing, and night insulation as functions of their thermophysical properties and climatic conditions.« less

  10. Random medium model for cusping of plane waves.

    PubMed

    Li, Jia; Korotkova, Olga

    2017-09-01

    We introduce a model for a three-dimensional (3D) Schell-type stationary medium whose degree of potential's correlation satisfies the Fractional Multi-Gaussian (FMG) function. Compared with the scattered profile produced by the Gaussian Schell-model (GSM) medium, the Fractional Multi-Gaussian Schell-model (FMGSM) medium gives rise to a sharp concave intensity apex in the scattered field. This implies that the FMGSM medium also accounts for a larger than Gaussian's power in the bucket (PIB) in the forward scattering direction, hence being a better candidate than the GSM medium for generating highly-focused (cusp-like) scattered profiles in the far zone. Compared to other mathematical models for the medium's correlation function which can produce similar cusped scattered profiles the FMG function offers unprecedented tractability being the weighted superposition of Gaussian functions. Our results provide useful applications to energy counter problems and particle manipulation by weakly scattered fields.

  11. Reflection statistics of weakly disordered optical medium when its mean refractive index is different from an outside medium

    NASA Astrophysics Data System (ADS)

    Pradhan, Prabhakar; John Park, Daniel; Capoglu, Ilker; Subramanian, Hariharan; Damania, Dhwanil; Cherkezyan, Lusik; Taflove, Allen; Backman, Vadim

    2017-06-01

    Statistical properties of light waves reflected from a one-dimensional (1D) disordered optical medium [n(x) = n0+ dn(x), =0] have been well studied, however, most of the studies have focused on the situation when the mean refractive index of the optical medium matched with the outside medium, i.e., n0= nout=1. Further, considering dn(x) as a Gaussian color noise refractive index medium with exponential spatial correlation decay length lc and k as the incident wave vector, it has been shown that for smaller correlation length limit, i.e., klc <<1, both the mean reflection coefficient and std of r, σ(r), have same value, and they follow the relation = σ(r) ∝ lc. However, when the refractive index of the sample medium is different from the outside medium, the reflection statistics may have interesting features, which has not been well studied or understood. We studied the reflection statistics of a 1D weakly disordered optical medium with the mean background refractive index n0 being different from the outside medium nout (≠n0), to see the effect of mismatching (i.e., value of n0- nout) on the reflection statistics. In the mismatched case, the results show that the mean reflection coefficient follows a form similar to that of the matched refractive-index case, i.e., lc, with a linear increased shift, which is due to 1D uniform background reflection from a slab. However, σ(r) is shown to be σ(r) ∝ (lc)1/2, which is different from the matched case. This change in std of r is attributed to the interference between the mismatched-crerated edge mediated multiple scattering that are coupled with the random scattering. Applications to light scattering from random layered media and biological cells are discussed.

  12. Using Remote Sensing and Radar MET Data to Support Watershed Assessments Comprising IEM

    EPA Science Inventory

    Meteorological (MET) data required by watershed assessments that comprise Integrated Environmental Modeling (IEM) have traditionally been provided by land-based weather (gauge) stations; although these data may not be most appropriate for describing adequate spatial and temporal...

  13. Thermal Impact of Medium Deep Borehole Thermal Energy Storage on the Shallow Subsurface

    NASA Astrophysics Data System (ADS)

    Welsch, Bastian; Schulte, Daniel O.; Rühaak, Wolfram; Bär, Kristian; Sass, Ingo

    2017-04-01

    Borehole heat exchanger arrays are a well-suited and already widely applied method for exploiting the shallow subsurface as seasonal heat storage. However, in most of the populated regions the shallow subsurface also comprises an important aquifer system used for drinking water production. Thus, the operation of shallow geothermal heat storage systems leads to a significant increase in groundwater temperatures in the proximity of the borehole heat exchanger array. The magnitude of the impact on groundwater quality and microbiology associated with this temperature rise is controversially discussed. Nevertheless, the protection of shallow groundwater resources has priority. Accordingly, water authorities often follow restrictive permission policies for building such storage systems. An alternative approach to avoid this issue is the application of medium deep borehole heat exchanger arrays instead of shallow ones. The thermal impact on shallow aquifers can be significantly reduced as heat is stored at larger depth. Moreover, it can be further diminished by the installation of a thermally insulating materials in the upper section of the borehole heat exchangers. Based on a numerical simulation study, the advantageous effects of medium deep borehole thermal energy storage are demonstrated and quantified. A finite element software is used to model the heat transport in the subsurface in 3D, while the heat transport in the borehole heat exchangers is solved analytically in 1D. For this purpose, an extended analytical solution is implemented, which also allows for the consideration of a thermally insulating borehole section.

  14. Changes of MK medium during storage of human cornea.

    PubMed Central

    Hasany, S M; Basu, P K

    1987-01-01

    By comparing the composition of McCarey-Kaufman (MK) medium before and after corneal storage we attempted to identify specific physiological changes in the medium as predictors of tissue damage. We also tried to determine if hydrocortisone (a lysosomal membrane stabiliser) added to the medium could reduce tissue damage during storage. Corneas (human and rabbit) were stored in the MK medium with and without hydrocortisone for 4 days at 4 degrees C. The water and nitrogen contents of the stored cornea were compared with those of the fresh cornea. The medium was analysed before and after corneal storage to determine the concentrations of glucose, protein, and amino acids as well as pH and osmolarity. Scanning electron microscopy (SEM) was used to estimate the degree of the corneal endothelial cell damage. The nitrogen contents and dry weights of the steroid treated and untreated stored corneas were similar to those of the fresh unstored cornea. The steroid treated cornea contained a lesser amount of water than the untreated cornea. The cornea stored in medium without steroid took up a greater amount of glucose from the medium than the cornea stored in medium with steroid. As compared with their concentrations in the fresh unused medium the concentrations of leucine, lysine, and glycine were lower and that of glutamic acid was higher in both the media used for corneal storage. However, the steroid treated storage medium as compared with the untreated storage medium had a greater reduction in the lowering of leucine, lysine, and glycine, and a lesser reduction in the increase of glutamic acid. Steroid treated medium also had a lesser amount of protein released from the stored cornea. Changes in the pH and osmolarity of the media before and after corneal storage were not remarkable. SEM showed that the endothelial cells of the cornea stored in the medium containing steroid were less damaged than those of the cornea stored in the medium without steroid. Images PMID

  15. Propagating modes in gain-guided optical fibers.

    PubMed

    Siegman, A E

    2003-08-01

    Optical fibers in which gain-guiding effects are significant or even dominant compared with conventional index guiding may become of practical interest for future high-power single-mode fiber lasers. I derive the propagation characteristics of symmetrical slab waveguides and cylindrical optical fibers having arbitrary amounts of mixed gain and index guiding, assuming a single uniform transverse profile for both the gain and the refractive-index steps. Optical fibers of this type are best characterized by using a complex-valued v-squared parameter in place of the real-valued v parameter commonly used to describe conventional index-guided optical fibers.

  16. Electrical gain in interband cascade infrared photodetectors

    NASA Astrophysics Data System (ADS)

    Huang, Wenxiang; Li, Lu; Lei, Lin; Massengale, Jeremy A.; Yang, Rui Q.; Mishima, Tetsuya D.; Santos, Michael B.

    2018-03-01

    In order to achieve improved understanding and gain insights into the device operation of interband cascade infrared photodetectors (ICIPs) and ultimately to optimize the design, we present a comparative study of five long-wavelength (LW) ICIPs based on a type-II InAs/GaSb superlattice. This study shows how the device responsivity is affected by the individual absorber thicknesses and the number of cascade stages, through the impact of light attenuation. Additionally, this study further validates that the electrical gain universally exists in non-current-matched ICIPs. With multiple cascade stages to suppress noise, these LW ICIPs achieved superior device performance at high temperatures, in terms of Johnson-noise limited detectivities, compared to commercial MCT detectors. Furthermore, a theory is developed to quantitatively describe the electrical gain in ICIPs and our calculations are in good agreement with the experimental results. Based on the theory, the optimal number of stages for maximizing the device detectivity D* is identified with inclusion of the electrical gain. Our calculation shows that this optimal number of stages is relatively large in the presence of the gain and the maximized D* has a relatively weak dependence on the absorber thickness when it is sufficiently thin.

  17. Adequacy of Prenatal Care and Gestational Weight Gain

    PubMed Central

    Crandell, Jamie L.; Jones-Vessey, Kathleen

    2016-01-01

    Abstract Background: The goal of prenatal care is to maximize health outcomes for a woman and her fetus. We examined how prenatal care is associated with meeting the 2009 Institute of Medicine (IOM) guidelines for gestational weight gain. Sample: The study used deidentified birth certificate data supplied by the North Carolina State Center for Health Statistics. The sample included 197,354 women (≥18 years) who delivered singleton full-term infants in 2011 and 2012. Methods: A generalized multinomial model was used to identify how adequate prenatal care was associated with the odds of gaining excessive or insufficient weight during pregnancy according to the 2009 IOM guidelines. The model adjusted for prepregnancy body size, sociodemographic factors, and birth weight. Results: A total of 197,354 women (≥18 years) delivered singleton full-term infants. The odds ratio (OR) for excessive weight gain was 2.44 (95% CI 2.37–2.50) in overweight and 2.33 (95% CI 2.27–2.40) in obese women compared with normal weight women. The OR for insufficient weight gain was 1.15 (95% CI 1.09–1.22) for underweight and 1.34 (95% CI 1.30–1.39) for obese women compared with normal weight women. Prenatal care at the inadequate or intermediate levels was associated with insufficient weight gain (OR: 1.32, 95% CI 1.27–1.38; OR: 1.15, 95% CI 1.09–1.21, respectively) compared with adequate prenatal care. Women with inadequate care were less likely to gain excessive weight (OR: 0.88, 95% CI 0.86–0.91). Conclusions: Whereas prenatal care was effective for preventing insufficient weight gain regardless of prepregnancy body size, educational background, and racial/ethnic group, there were no indications that adequate prenatal care was associated with reduced risk for excessive gestational weight gain. Further research is needed to improve prenatal care programs for preventing excess weight gain. PMID:26741198

  18. Chemically Defined Medium and Caenorhabditis elegans: A Powerful Approach

    NASA Technical Reports Server (NTRS)

    Szewczyk, N. J.; Kozak, E.; Conley, C. A.

    2003-01-01

    C. elegans has been established as a powerful genetic system. Growth in a chemically defined medium (C. elegans Maintenance Medium (CeMM)) now allows standardization and systematic manipulation of the nutrients that animals receive. Liquid cultivation allows automated culturing and experimentation and should be of me in large-scale growth and screening of animals. Here we present our initial results from developing culture systems with CeMM. We find that CeMM is versatile and culturing is simple. CeMM can be used in a solid or liquid state, it can be stored unused for at least a year, unattended actively growing cultures may be maintained longer than with standard techniques, and standard C. elegans protocols work well with animals grown in defined medium. We also find that there are caveats of using defined medium. Animals in defined medium grow more slowly than on standard medium, appear to display adaptation to the defined medium, and display altered growth rates as they change defined medium composition. As was suggested with the introduction of C. elegans as a potential genetic system, use of defined medium with C. elegans should prove a powerful tool.

  19. Self-composite comprised of nanocrystalline diamond and a non-diamond component useful for thermoelectric applications

    DOEpatents

    Gruen, Dieter M.

    2012-09-04

    One provides nanocrystalline diamond material that comprises a plurality of substantially ordered diamond crystallites that are sized no larger than about 10 nanometers. One then disposes a non-diamond component within the nanocrystalline diamond material. By one approach this non-diamond component comprises an electrical conductor that is formed at the grain boundaries that separate the diamond crystallites from one another. The resultant nanowire is then able to exhibit a desired increase with respect to its ability to conduct electricity while also preserving the thermal conductivity behavior of the nanocrystalline diamond material.

  20. Self-composite comprised of nanocrystalline diamond and a non-diamond component useful for thermoelectric applications

    DOEpatents

    Gruen, Dieter M [Downers Grove, IL

    2009-08-11

    One provides nanocrystalline diamond material that comprises a plurality of substantially ordered diamond crystallites that are sized no larger than about 10 nanometers. One then disposes a non-diamond component within the nanocrystalline diamond material. By one approach this non-diamond component comprises an electrical conductor that is formed at the grain boundaries that separate the diamond crystallites from one another. The resultant nanowire is then able to exhibit a desired increase with respect to its ability to conduct electricity while also preserving the thermal conductivity behavior of the nanocrystalline diamond material.

  1. Quantifying the mechanisms of domain gain in animal proteins.

    PubMed

    Buljan, Marija; Frankish, Adam; Bateman, Alex

    2010-01-01

    Protein domains are protein regions that are shared among different proteins and are frequently functionally and structurally independent from the rest of the protein. Novel domain combinations have a major role in evolutionary innovation. However, the relative contributions of the different molecular mechanisms that underlie domain gains in animals are still unknown. By using animal gene phylogenies we were able to identify a set of high confidence domain gain events and by looking at their coding DNA investigate the causative mechanisms. Here we show that the major mechanism for gains of new domains in metazoan proteins is likely to be gene fusion through joining of exons from adjacent genes, possibly mediated by non-allelic homologous recombination. Retroposition and insertion of exons into ancestral introns through intronic recombination are, in contrast to previous expectations, only minor contributors to domain gains and have accounted for less than 1% and 10% of high confidence domain gain events, respectively. Additionally, exonization of previously non-coding regions appears to be an important mechanism for addition of disordered segments to proteins. We observe that gene duplication has preceded domain gain in at least 80% of the gain events. The interplay of gene duplication and domain gain demonstrates an important mechanism for fast neofunctionalization of genes.

  2. Effects of having a baby on weight gain.

    PubMed

    Brown, Wendy J; Hockey, Richard; Dobson, Annette J

    2010-02-01

    Women often blame weight gain in early adulthood on having a baby. The aim was to estimate the weight gain attributable to having a baby, after disentangling the effects of other factors that influence weight change at this life stage. A longitudinal study of a randomly selected cohort of 6458 Australian women, aged 18-23 years in 1996, was conducted. Self-report mailed surveys were completed in 1996, 2000, 2003, and 2006, and data were analyzed in 2008. On average, women gained weight at the rate of 0.93% per year (95% CI=0.89, 0.98) or 605 g/year (95% CI=580, 635) for a 65-kg woman. Over the 10-year study period, partnered women with one baby gained almost 4 kg more, and those with a partner but no baby gained 1.8 kg more, than unpartnered childless women (after adjustment for other significant factors: initial BMI and age; physical activity, sitting time, energy intake (2003); education level, hours in paid work, and smoking). Having a baby has a marked effect on 10-year weight gain, but there is also an effect attributable to getting married or living with a partner. Social and lifestyle as well as energy balance variables should be considered when developing strategies to prevent weight gain in young adult women. Copyright 2010 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  3. Temporal Gain Correction for X-Ray Calorimeter Spectrometers

    NASA Technical Reports Server (NTRS)

    Porter, F. S.; Chiao, M. P.; Eckart, M. E.; Fujimoto, R.; Ishisaki, Y.; Kelley, R. L.; Kilbourne, C. A.; Leutenegger, M. A.; McCammon, D.; Mitsuda, K.

    2016-01-01

    Calorimetric X-ray detectors are very sensitive to their environment. The boundary conditions can have a profound effect on the gain including heat sink temperature, the local radiation temperature, bias, and the temperature of the readout electronics. Any variation in the boundary conditions can cause temporal variations in the gain of the detector and compromise both the energy scale and the resolving power of the spectrometer. Most production X-ray calorimeter spectrometers, both on the ground and in space, have some means of tracking the gain as a function of time, often using a calibration spectral line. For small gain changes, a linear stretch correction is often sufficient. However, the detectors are intrinsically non-linear and often the event analysis, i.e., shaping, optimal filters etc., add additional non-linearity. Thus for large gain variations or when the best possible precision is required, a linear stretch correction is not sufficient. Here, we discuss a new correction technique based on non-linear interpolation of the energy-scale functions. Using Astro-HSXS calibration data, we demonstrate that the correction can recover the X-ray energy to better than 1 part in 104 over the entire spectral band to above 12 keV even for large-scale gain variations. This method will be used to correct any temporal drift of the on-orbit per-pixel gain using on-board calibration sources for the SXS instrument on the Astro-H observatory.

  4. Compensated gain control circuit for buck regulator command charge circuit

    DOEpatents

    Barrett, David M.

    1996-01-01

    A buck regulator command charge circuit includes a compensated-gain control signal for compensating for changes in the component values in order to achieve optimal voltage regulation. The compensated-gain control circuit includes an automatic-gain control circuit for generating a variable-gain control signal. The automatic-gain control circuit is formed of a precision rectifier circuit, a filter network, an error amplifier, and an integrator circuit.

  5. Assessment of learning gains in a flipped biochemistry classroom.

    PubMed

    Ojennus, Deanna Dahlke

    2016-01-01

    The flipped classroom has become an increasingly popular pedagogical approach to teaching and learning. In this study, learning gains were assessed in a flipped biochemistry course and compared to gains in a traditional lecture. Although measured learning gains were not significantly different between the two courses, student perception of learning gains did differ and indicates a higher level of satisfaction with the flipped lecture format. © 2015 The International Union of Biochemistry and Molecular Biology.

  6. Ultra-high gain diffusion-driven organic transistor

    PubMed Central

    Torricelli, Fabrizio; Colalongo, Luigi; Raiteri, Daniele; Kovács-Vajna, Zsolt Miklós; Cantatore, Eugenio

    2016-01-01

    Emerging large-area technologies based on organic transistors are enabling the fabrication of low-cost flexible circuits, smart sensors and biomedical devices. High-gain transistors are essential for the development of large-scale circuit integration, high-sensitivity sensors and signal amplification in sensing systems. Unfortunately, organic field-effect transistors show limited gain, usually of the order of tens, because of the large contact resistance and channel-length modulation. Here we show a new organic field-effect transistor architecture with a gain larger than 700. This is the highest gain ever reported for organic field-effect transistors. In the proposed organic field-effect transistor, the charge injection and extraction at the metal–semiconductor contacts are driven by the charge diffusion. The ideal conditions of ohmic contacts with negligible contact resistance and flat current saturation are demonstrated. The approach is general and can be extended to any thin-film technology opening unprecedented opportunities for the development of high-performance flexible electronics. PMID:26829567

  7. Ultra-high gain diffusion-driven organic transistor.

    PubMed

    Torricelli, Fabrizio; Colalongo, Luigi; Raiteri, Daniele; Kovács-Vajna, Zsolt Miklós; Cantatore, Eugenio

    2016-02-01

    Emerging large-area technologies based on organic transistors are enabling the fabrication of low-cost flexible circuits, smart sensors and biomedical devices. High-gain transistors are essential for the development of large-scale circuit integration, high-sensitivity sensors and signal amplification in sensing systems. Unfortunately, organic field-effect transistors show limited gain, usually of the order of tens, because of the large contact resistance and channel-length modulation. Here we show a new organic field-effect transistor architecture with a gain larger than 700. This is the highest gain ever reported for organic field-effect transistors. In the proposed organic field-effect transistor, the charge injection and extraction at the metal-semiconductor contacts are driven by the charge diffusion. The ideal conditions of ohmic contacts with negligible contact resistance and flat current saturation are demonstrated. The approach is general and can be extended to any thin-film technology opening unprecedented opportunities for the development of high-performance flexible electronics.

  8. Ultra-high gain diffusion-driven organic transistor

    NASA Astrophysics Data System (ADS)

    Torricelli, Fabrizio; Colalongo, Luigi; Raiteri, Daniele; Kovács-Vajna, Zsolt Miklós; Cantatore, Eugenio

    2016-02-01

    Emerging large-area technologies based on organic transistors are enabling the fabrication of low-cost flexible circuits, smart sensors and biomedical devices. High-gain transistors are essential for the development of large-scale circuit integration, high-sensitivity sensors and signal amplification in sensing systems. Unfortunately, organic field-effect transistors show limited gain, usually of the order of tens, because of the large contact resistance and channel-length modulation. Here we show a new organic field-effect transistor architecture with a gain larger than 700. This is the highest gain ever reported for organic field-effect transistors. In the proposed organic field-effect transistor, the charge injection and extraction at the metal-semiconductor contacts are driven by the charge diffusion. The ideal conditions of ohmic contacts with negligible contact resistance and flat current saturation are demonstrated. The approach is general and can be extended to any thin-film technology opening unprecedented opportunities for the development of high-performance flexible electronics.

  9. 7 CFR 51.2751 - U.S. Medium Virginia.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false U.S. Medium Virginia. 51.2751 Section 51.2751 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... § 51.2751 U.S. Medium Virginia. “U.S. Medium Virginia” consists of shelled Virginia type peanut kernels...

  10. 7 CFR 51.2751 - U.S. Medium Virginia.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false U.S. Medium Virginia. 51.2751 Section 51.2751 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... § 51.2751 U.S. Medium Virginia. “U.S. Medium Virginia” consists of shelled Virginia type peanut kernels...

  11. Incompatibility of Contrast Medium and Trisodium Citrate

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Delcour, Christian, E-mail: christian.delcour@chu-charleroi.be; Bruninx, Guy

    2013-02-15

    To test the compatibility of trisodium citrate, a catheter lock solution, with iodinated contrast medium. Iohexol, iobitridol, iodixanol, ioxaglate, ioxithalamate, iomeprol, and iopromide were tested. In all tests, 2 ml of contrast medium were mixed with 2 ml of trisodium citrate solution. Iodixanol and ioxaglate provoked a highly viscous gluelike precipitation when mixed with trisodium citrate. A brief transient precipitate was observed with iohexol, iomeprol, and ioxithalamate. Permanent precipitation occurred with iobitridol and iopromide. One must be aware of the potential for precipitation when contrast medium is mixed with trisodium citrate solution. Before trisodium citrate solution is injected, the cathetermore » should be thoroughly flushed with saline if a contrast medium has previously been injected through it.« less

  12. REVIEWS OF TOPICAL PROBLEMS The quark-gluon medium

    NASA Astrophysics Data System (ADS)

    Dremin, Igor M.; Leonidov, Andrei V.

    2011-02-01

    The properties of the quark-gluon medium observed in high-energy nucleus-nucleus collisions are discussed. The main experimental facts about these collisions are briefly described and compared with data about proton-proton collisions. Both microscopic and macroscopic approaches to their description are reviewed. The chromodynamics of the quark-gluon medium at high energies is mainly considered. The energy loss of partons moving in this medium is treated. The principal conclusion is that the medium possesses some collective properties which are crucial for understanding the experimental observations.

  13. Using Remote Sensing and Radar MET Data to Support Watershed Assessments Comprising IEM

    USDA-ARS?s Scientific Manuscript database

    Meteorological (MET) data required by watershed assessments that comprise Integrated Environmental Modeling (IEM) have traditionally been provided by land-based weather (gauge) stations; although these data may not be most appropriate for describing adequate spatial and temporal resolution if the ME...

  14. Compensated gain control circuit for buck regulator command charge circuit

    DOEpatents

    Barrett, D.M.

    1996-11-05

    A buck regulator command charge circuit includes a compensated-gain control signal for compensating for changes in the component values in order to achieve optimal voltage regulation. The compensated-gain control circuit includes an automatic-gain control circuit for generating a variable-gain control signal. The automatic-gain control circuit is formed of a precision rectifier circuit, a filter network, an error amplifier, and an integrator circuit. 5 figs.

  15. 24 CFR 3280.507 - Comfort heat gain.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Comfort heat gain. 3280.507 Section... DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.507 Comfort heat... part. (a) Transmission heat gains. Homes complying with this section shall meet the minimum heat loss...

  16. 24 CFR 3280.507 - Comfort heat gain.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 5 2014-04-01 2014-04-01 false Comfort heat gain. 3280.507 Section... DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.507 Comfort heat... part. (a) Transmission heat gains. Homes complying with this section shall meet the minimum heat loss...

  17. 24 CFR 3280.507 - Comfort heat gain.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Comfort heat gain. 3280.507 Section... DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.507 Comfort heat... part. (a) Transmission heat gains. Homes complying with this section shall meet the minimum heat loss...

  18. 24 CFR 3280.507 - Comfort heat gain.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Comfort heat gain. 3280.507 Section... DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.507 Comfort heat... part. (a) Transmission heat gains. Homes complying with this section shall meet the minimum heat loss...

  19. Adsorption of non-ionic ABC triblock copolymers: Surface modification of TiO2 suspensions in aqueous and non-aqueous medium

    NASA Astrophysics Data System (ADS)

    Lerch, Jean-Philippe; Atanase, Leonard Ionut; Riess, Gérard

    2017-10-01

    A series of non-ionic ABC triblock copolymers, such as poly(butadiene)-b-poly(2-vinylpyrridine)-b-poly(ethylene oxide) (PB-P2VP-PEO) were synthesized by sequential anionic polymerizations. For these copolymers comprising an organo-soluble PB and a water-soluble PEO block, their P2VP middle block has been selected for its anchoring capacity on solid surfaces. The adsorption isotherms on TiO2 were obtained in heptane and in aqueous medium, as selective solvents. In both of these cases, the P2VP middle block provides the surface anchoring, whereas PB and PEO sequences are acting as stabilizing moieties in heptane and water respectively. By extension to ABC triblock copolymers of the scaling theory developed for diblock copolymers, the density of adsorbed chains could be correlated with the molecular characteristics of the PB-P2VP-PEO triblock copolymers. From a practical point a view, it could be demonstrated that these copolymers are efficient dispersing agents for the TiO2 pigments in both aqueous and non-aqueous medium.

  20. 7 CFR 51.2751 - U.S. Medium Virginia.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false U.S. Medium Virginia. 51.2751 Section 51.2751... STANDARDS) United States Standards for Shelled Virginia Type Peanuts Grades § 51.2751 U.S. Medium Virginia. “U.S. Medium Virginia” consists of shelled Virginia type peanut kernels of similar varietal...

  1. 7 CFR 51.2751 - U.S. Medium Virginia.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false U.S. Medium Virginia. 51.2751 Section 51.2751... STANDARDS) United States Standards for Shelled Virginia Type Peanuts Grades § 51.2751 U.S. Medium Virginia. “U.S. Medium Virginia” consists of shelled Virginia type peanut kernels of similar varietal...

  2. 7 CFR 51.2751 - U.S. Medium Virginia.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false U.S. Medium Virginia. 51.2751 Section 51.2751... STANDARDS) United States Standards for Shelled Virginia Type Peanuts Grades § 51.2751 U.S. Medium Virginia. “U.S. Medium Virginia” consists of shelled Virginia type peanut kernels of similar varietal...

  3. A Comparative Study on the Effectiveness of English-Medium and Turkish-Medium Accounting Education: Gazi University Case

    ERIC Educational Resources Information Center

    Zaif, Figen; Karapinar, Aydin; Yangin Eksi, Gonca

    2017-01-01

    The authors explore the effect of medium of instruction on students' attainments at a large state university in Turkey in the Department of Business Administration. The findings indicate no statistically significant difference in grades of 386 students with respect to medium of instruction. As for entry rankings however, those in the…

  4. Method for increasing the rate of compressive strength gain in hardenable mixtures containing fly ash

    DOEpatents

    Liskowitz, J.W.; Wecharatana, M.; Jaturapitakkul, C.; Cerkanowicz, A.E.

    1997-10-28

    The present invention relates to concrete, mortar and other hardenable mixtures comprising cement and fly ash for use in construction. The invention provides a method for increasing the rate of strength gain of a hardenable mixture containing fly ash by exposing the fly ash to an aqueous slurry of calcium oxide (lime) prior to its incorporation into the hardenable mixture. The invention further relates to such hardenable mixtures, e.g., concrete and mortar, that contain fly ash pre-reacted with calcium oxide. In particular, the fly ash is added to a slurry of calcium oxide in water, prior to incorporating the fly ash in a hardenable mixture. The hardenable mixture may be concrete or mortar. In a specific embodiment, mortar containing fly ash treated by exposure to an aqueous lime slurry are prepared and tested for compressive strength at early time points. 2 figs.

  5. Non-aqueous liquid compositions comprising ion exchange polymers reference to related application

    DOEpatents

    Kim,; Yu Seung, Lee [Los Alamos, NM; Kwan-Soo, Rockward [Los Alamos, NM; T, Tommy Q [Rio Rancho, NM

    2012-08-07

    Compositions, and methods of making thereof, comprising from about 1% to about 5% of a perfluorinated sulfonic acid ionomer or a hydrocarbon-based ionomer; and from about 95% to about 99% of a solvent, said solvent consisting essentially of a polyol; wherein said composition is substantially free of water and wherein said ionomer is uniformly dispersed in said solvent.

  6. Boric acid-enhanced embedding medium for cryomicrotomy.

    PubMed

    Lim, Jin Ik; Park, Hun-Kuk

    2012-05-01

    A polyvinyl alcohol (PVA)/polyethylene glycol (PEG)-based resin is commonly used as a cryoembedding medium for the histological analysis of frozen tissue sections. However, it is not easy to obtain sufficient numbers of satisfactory reproducible sections owing to the differences between the mechanical properties of the medium and embedded tissue and the low cohesive force of the medium. We describe a modified PVA-based cryoembedding medium, composed of PVA (10wt% and 15wt%) with the addition of boric acid (from 0 to 5wt%), that can improve the sectioning properties and efficiency of frozen tissue for histological analysis. The amount of load under the same compressive displacement as well as cohesive force increased with increasing boric acid and PVA contents. 15wt% PVA and 3wt% boric acid was determined as an optimal composition for cryoembedding material based on the sectioning efficiency measured by the numbers of unimpaired sectioned slices and the amount of load under the same compressive displacement test. On the basis of the results of routine hematoxylin and eosin staining of cryosections of tissue embedded in a medium with 3wt% boric acid and PVA, it was concluded that the modified PVA cryoembedding medium can improve the efficiency of cryosectioning for subsequent histological or histochemical analysis of various tissues. Copyright © 2011 Elsevier GmbH. All rights reserved.

  7. How Does the Medium Affect the Message?

    ERIC Educational Resources Information Center

    Dommermuth, William P.

    1974-01-01

    This experimental comparison of the advertising effectiveness of television, movies, radio, and print finds no support for McLuhan's idea that television is a "cool" medium and movies are a "hot" medium. (RB)

  8. Lime-amended growing medium causes seedling growth distortions

    Treesearch

    R. Kasten Dumroese; Gale Thompson; David L. Wenny

    1990-01-01

    Although a commercial growing medium with incorporated agricultural lime had been successfully used for years, it caused growth distortion of coniferous and deciduous seedlings during 1988. Seedlings grown in the amended medium were stunted and chlorotic, often with disfigured needles and multiple tops. Seedlings grown in the same medium without incorporated lime grew...

  9. Edemagenic gain and interstitial fluid volume regulation.

    PubMed

    Dongaonkar, R M; Quick, C M; Stewart, R H; Drake, R E; Cox, C S; Laine, G A

    2008-02-01

    Under physiological conditions, interstitial fluid volume is tightly regulated by balancing microvascular filtration and lymphatic return to the central venous circulation. Even though microvascular filtration and lymphatic return are governed by conservation of mass, their interaction can result in exceedingly complex behavior. Without making simplifying assumptions, investigators must solve the fluid balance equations numerically, which limits the generality of the results. We thus made critical simplifying assumptions to develop a simple solution to the standard fluid balance equations that is expressed as an algebraic formula. Using a classical approach to describe systems with negative feedback, we formulated our solution as a "gain" relating the change in interstitial fluid volume to a change in effective microvascular driving pressure. The resulting "edemagenic gain" is a function of microvascular filtration coefficient (K(f)), effective lymphatic resistance (R(L)), and interstitial compliance (C). This formulation suggests two types of gain: "multivariate" dependent on C, R(L), and K(f), and "compliance-dominated" approximately equal to C. The latter forms a basis of a novel method to estimate C without measuring interstitial fluid pressure. Data from ovine experiments illustrate how edemagenic gain is altered with pulmonary edema induced by venous hypertension, histamine, and endotoxin. Reformulation of the classical equations governing fluid balance in terms of edemagenic gain thus yields new insight into the factors affecting an organ's susceptibility to edema.

  10. System and method for treatment of a medium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Singh, Surinder Prabhjot; Acharya, Harish Radhakrishna; Perry, Robert James

    2017-05-23

    A system and method for treatment of a medium is disclosed. The system includes a plurality of separator zones and a plurality of heat transfer zones. Each of the separator zone and the heat transfer zone among the plurality of separator zones and heat transfer zones respectively, are disposed alternatively in a flow duct. Further, each separator zone includes an injector device for injecting a sorbent into the corresponding separator zone. Within the corresponding separator zone, the injected sorbent is reacted with a gaseous medium flowing in the flow duct, so as to generate a reacted gaseous medium and amore » reacted sorbent. Further, each heat transfer zone exchanges heat between the reacted gaseous medium fed from the corresponding separator zone and a heat transfer medium.« less

  11. 20 CFR 416.910 - Meaning of substantial gainful activity.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false Meaning of substantial gainful activity. 416....910 Meaning of substantial gainful activity. Substantial gainful activity means work that— (a) Involves doing significant and productive physical or mental duties; and (b) Is done (or intended) for pay...

  12. 20 CFR 416.910 - Meaning of substantial gainful activity.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Meaning of substantial gainful activity. 416....910 Meaning of substantial gainful activity. Substantial gainful activity means work that— (a) Involves doing significant and productive physical or mental duties; and (b) Is done (or intended) for pay...

  13. 27 CFR 19.675 - Medium plant permit applications.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Medium plant permit... Obtaining A Permit § 19.675 Medium plant permit applications. (a) General. Any person wishing to establish a medium plant must file form TTB F 5110.74, Application and Permit for an Alcohol Fuel Producer Under 26 U...

  14. 27 CFR 19.675 - Medium plant permit applications.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Medium plant permit... Obtaining A Permit § 19.675 Medium plant permit applications. (a) General. Any person wishing to establish a medium plant must file form TTB F 5110.74, Application and Permit for an Alcohol Fuel Producer Under 26 U...

  15. 27 CFR 19.675 - Medium plant permit applications.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Medium plant permit... Obtaining A Permit § 19.675 Medium plant permit applications. (a) General. Any person wishing to establish a medium plant must file form TTB F 5110.74, Application and Permit for an Alcohol Fuel Producer Under 26 U...

  16. 27 CFR 19.675 - Medium plant permit applications.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Medium plant permit... Obtaining A Permit § 19.675 Medium plant permit applications. (a) General. Any person wishing to establish a medium plant must file form TTB F 5110.74, Application and Permit for an Alcohol Fuel Producer Under 26 U...

  17. CASBaH: the Multiphase Circumgalactic Medium During the Decline of Cosmic Star Formation

    NASA Astrophysics Data System (ADS)

    Burchett, Joseph N.; Tripp, Todd; Prochaska, Jason; Werk, Jessica; Willmer, Christopher; Ford, Amanda Brady; Howk, Chris

    2018-01-01

    The COS Absorption Survey of Baryon Harbors (CASBaH) comprises high-S/N spectra of nine z > 0.9 QSOs with coverage from the far-ultraviolet to the optical. These sightlines access the rich suite of rest-frame extreme-ultraviolet (600 - 1000 Angstroms) spectral transitions, such as Ne VIII, Mg X, and O II/III/IV, in addition to those more well studied at longer wavelengths (O VI, C III, Mg II). We have undertaken a large ground-based spectroscopic follow-up campaign to identify galaxies projected near the QSO sightlines and leverage the myriad diagnostics within the QSO spectra to study the circumgalactic medium (CGM) at 0.2 < z < 1 over the crucial epoch when star formation activity in the Universe was in sharp decline. We will present results from this multiwavelength study characterizing the CGM across multiple ionization states, focusing on the O VI and Ne VIII-probed warm-hot (105-106 K) gas within the halos of our galaxy sample.

  18. A Review of Supply Chain Collaboration Practices for Small and Medium-sized Manufacturers

    NASA Astrophysics Data System (ADS)

    Wee, SY; Thoo, AC; Z, Sulaiman; FM, Muharam

    2016-05-01

    For the decades, organizations have endeavored to look for external sources for opportunities to achieve efficient and responsive supply chain with their partners especially for small and medium manufacturers (SMM). In this scenario, supply chain collaboration (SCC) is an interaction between supply chain members with the purpose of utilizes the knowledge and resources of customers and suppliers, and integrates the flows of products and information in order to achieve a common goal and obtain mutual benefit. The essential SCC dimensions for SMMs comprised of information sharing, joint knowledge creation, joint decision making, goal congruence and incentive sharing. The successful implementation of SCC can give SMMs an edge over their competitors. This paper aims to introduce a review of SCC practices for SMM. Overall, the findings provide managerial insights for the SMM in SCC implementation owing to resource scarcity and the need to draw SCC in order to ensure a sustainable competitive advantage.

  19. Focusing on Short-Term Achievement Gains Fails to Produce Long-Term Gains

    ERIC Educational Resources Information Center

    Grissmer, David W.; Ober, David R.; Beekman, John A.

    2014-01-01

    The short-term emphasis engendered by No Child Left Behind (NCLB) has focused research predominantly on unraveling the complexities and uncertainties in assessing short-term results, rather than developing methods and assessing results over the longer term. In this paper we focus on estimating long-term gains and address questions important to…

  20. The Protective Effect of Agaricus blazei Murrill, Submerged Culture Using the Optimized Medium Composition, on Alcohol-Induced Liver Injury

    PubMed Central

    Wang, Hang; Li, Gang; Zhang, Wenyu; Han, Chunchao; Xu, Xin; Li, Yong-Ping

    2014-01-01

    Agaricus blazei Murrill (ABM), an edible mushroom native to Brazil, is widely used for nonprescript and medicinal purposes. Alcohol liver disease (ALD) is considered as a leading cause for a liver injury in modern dietary life, which can be developed by a prolonged or large intake of alcohol. In this study, the medium composition of ABM was optimized using response surface methodology for maximum mycelial biomass and extracellular polysaccharide (EPS) production. The model predicts to gain a maximal mycelial biomass and extracellular polysaccharide at 1.047 g/100 mL, and 0.367 g/100 mL, respectively, when the potato is 29.88 g/100 mL, the glucose is 1.01 g/100 mL, and the bran is 1.02 g/100 mL. The verified experiments showed that the model was significantly consistent with the model prediction and that the trends of mycelial biomass and extracellular polysaccharide were predicted by artificial neural network. After that, the optimized medium was used for the submerged culture of ABM. Then, alcohol-induced liver injury in mice model was used to examine the protective effect of ABM cultured using the optimized medium on the liver. And the hepatic histopathological observations showed that ABM had a relatively significant role in mice model, which had alcoholic liver damage. PMID:25114908

  1. The protective effect of Agaricus blazei Murrill, submerged culture using the optimized medium composition, on alcohol-induced liver injury.

    PubMed

    Wang, Hang; Li, Gang; Zhang, Wenyu; Han, Chunchao; Xu, Xin; Li, Yong-Ping

    2014-01-01

    Agaricus blazei Murrill (ABM), an edible mushroom native to Brazil, is widely used for nonprescript and medicinal purposes. Alcohol liver disease (ALD) is considered as a leading cause for a liver injury in modern dietary life, which can be developed by a prolonged or large intake of alcohol. In this study, the medium composition of ABM was optimized using response surface methodology for maximum mycelial biomass and extracellular polysaccharide (EPS) production. The model predicts to gain a maximal mycelial biomass and extracellular polysaccharide at 1.047 g/100 mL, and 0.367 g/100 mL, respectively, when the potato is 29.88 g/100 mL, the glucose is 1.01 g/100 mL, and the bran is 1.02 g/100 mL. The verified experiments showed that the model was significantly consistent with the model prediction and that the trends of mycelial biomass and extracellular polysaccharide were predicted by artificial neural network. After that, the optimized medium was used for the submerged culture of ABM. Then, alcohol-induced liver injury in mice model was used to examine the protective effect of ABM cultured using the optimized medium on the liver. And the hepatic histopathological observations showed that ABM had a relatively significant role in mice model, which had alcoholic liver damage.

  2. Serotonin Affects Movement Gain Control in the Spinal Cord

    PubMed Central

    Glaser, Joshua I.; Deng, Linna; Thompson, Christopher K.; Stevenson, Ian H.; Wang, Qining; Hornby, Thomas George; Heckman, Charles J.; Kording, Konrad P.

    2014-01-01

    A fundamental challenge for the nervous system is to encode signals spanning many orders of magnitude with neurons of limited bandwidth. To meet this challenge, perceptual systems use gain control. However, whether the motor system uses an analogous mechanism is essentially unknown. Neuromodulators, such as serotonin, are prime candidates for gain control signals during force production. Serotonergic neurons project diffusely to motor pools, and, therefore, force production by one muscle should change the gain of others. Here we present behavioral and pharmaceutical evidence that serotonin modulates the input–output gain of motoneurons in humans. By selectively changing the efficacy of serotonin with drugs, we systematically modulated the amplitude of spinal reflexes. More importantly, force production in different limbs interacts systematically, as predicted by a spinal gain control mechanism. Psychophysics and pharmacology suggest that the motor system adopts gain control mechanisms, and serotonin is a primary driver for their implementation in force production. PMID:25232107

  3. Sleeve Push Technique: A Novel Method of Space Gaining.

    PubMed

    Verma, Sanjeev; Bhupali, Nameksh Raj; Gupta, Deepak Kumar; Singh, Sombir; Singh, Satinder Pal

    2018-01-01

    Space gaining is frequently required in orthodontics. Multiple loops were initially used for space gaining and alignment. The most common used mechanics for space gaining is the use of nickel-titanium open coil springs. The disadvantage of nickel-titanium coil spring is that they cannot be used until the arches are well aligned to receive the stiffer stainless steel wires. Therefore, a new method of gaining space during initial alignment and leveling has been developed and named as sleeve push technique (SPT). The nickel-titanium wires, i.e. 0.012 inches and 0.014 inches along with archwire sleeve (protective tubing) can be used in a modified way to gain space along with alignment. This method helps in gaining space right from day 1 of treatment. The archwire sleeve and nickel-titanium wire in this new SPT act as a mutually synergistic combination and provide the orthodontist with a completely new technique for space opening.

  4. A variable-gain output feedback control design approach

    NASA Technical Reports Server (NTRS)

    Haylo, Nesim

    1989-01-01

    A multi-model design technique to find a variable-gain control law defined over the whole operating range is proposed. The design is formulated as an optimal control problem which minimizes a cost function weighing the performance at many operating points. The solution is obtained by embedding into the Multi-Configuration Control (MCC) problem, a multi-model robust control design technique. In contrast to conventional gain scheduling which uses a curve fit of single model designs, the optimal variable-gain control law stabilizes the plant at every operating point included in the design. An iterative algorithm to compute the optimal control gains is presented. The methodology has been successfully applied to reconfigurable aircraft flight control and to nonlinear flight control systems.

  5. Assessment of Learning Gains in a Flipped Biochemistry Classroom

    ERIC Educational Resources Information Center

    Ojennus, Deanna Dahlke

    2016-01-01

    The flipped classroom has become an increasingly popular pedagogical approach to teaching and learning. In this study, learning gains were assessed in a flipped biochemistry course and compared to gains in a traditional lecture. Although measured learning gains were not significantly different between the two courses, student perception of…

  6. 20 CFR 404.1510 - Meaning of substantial gainful activity.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false Meaning of substantial gainful activity. 404... Meaning of substantial gainful activity. Substantial gainful activity means work that— (a) Involves doing significant and productive physical or mental duties; and (b) Is done (or intended) for pay or profit. (See...

  7. 20 CFR 404.1510 - Meaning of substantial gainful activity.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Meaning of substantial gainful activity. 404... Meaning of substantial gainful activity. Substantial gainful activity means work that— (a) Involves doing significant and productive physical or mental duties; and (b) Is done (or intended) for pay or profit. (See...

  8. Linear-parameter-varying gain-scheduled control of aerospace systems

    NASA Astrophysics Data System (ADS)

    Barker, Jeffrey Michael

    The dynamics of many aerospace systems vary significantly as a function of flight condition. Robust control provides methods of guaranteeing performance and stability goals across flight conditions. In mu-syntthesis, changes to the dynamical system are primarily treated as uncertainty. This method has been successfully applied to many control problems, and here is applied to flutter control. More recently, two techniques for generating robust gain-scheduled controller have been developed. Linear fractional transformation (LFT) gain-scheduled control is an extension of mu-synthesis in which the plant and controller are explicit functions of parameters measurable in real-time. This LFT gain-scheduled control technique is applied to the Benchmark Active Control Technology (BACT) wing, and compared with mu-synthesis control. Linear parameter-varying (LPV) gain-scheduled control is an extension of Hinfinity control to parameter varying systems. LPV gain-scheduled control directly incorporates bounds on the rate of change of the scheduling parameters, and often reduces conservatism inherent in LFT gain-scheduled control. Gain-scheduled LPV control of the BACT wing compares very favorably with the LFT controller. Gain-scheduled LPV controllers are generated for the lateral-directional and longitudinal axes of the Innovative Control Effectors (ICE) aircraft and implemented in nonlinear simulations and real-time piloted nonlinear simulations. Cooper-Harper and pilot-induced oscillation ratings were obtained for an initial design, a reference aircraft and a redesign. Piloted simulation results for the initial LPV gain-scheduled control of the ICE aircraft are compared with results for a conventional fighter aircraft in discrete pitch and roll angle tracking tasks. The results for the redesigned controller are significantly better than both the previous LPV controller and the conventional aircraft.

  9. Gain determination of optical active doped planar waveguides

    NASA Astrophysics Data System (ADS)

    Šmejcký, J.; Jeřábek, V.; Nekvindová, P.

    2017-12-01

    This paper summarizes the results of the gain transmission characteristics measurement carried out on the new ion exchange Ag+ - Na+ optical Er3+ and Yb3+ doped active planar waveguides realized on a silica based glass substrates. The results were used for optimization of the precursor concentration in the glass substrates. The gain measurements were performed by the time domain method using a pulse generator, as well as broadband measurement method using supercontinuum optical source in the wavelength domain. Both methods were compared and the results were graphically processed. It has been confirmed that pulse method is useful as it provides a very accurate measurement of the gain - pumping power characteristics for one wavelength. In the case of radiation spectral characteristics, our measurement exactly determined the maximum gain wavelength bandwidth of the active waveguide. The spectral characteristics of the pumped and unpumped waveguides were compared. The gain parameters of the reported silica-based glasses can be compared with the phosphate-based parameters, typically used for optical active devices application.

  10. Evaluating realized genetic gains from tree improvement.

    Treesearch

    J.B. St. Clair

    1993-01-01

    Tree improvement has become an essential part of the management of forest lands for wood production, and predicting yields and realized gains from forests planted with genetically-improved trees will become increasingly important. This paper discusses concepts of tree improvement and genetic gain important to growth and yield modeling, and reviews previous studies of...

  11. The Interstellar Medium

    NASA Technical Reports Server (NTRS)

    Tielens, Alexander G. G. M.

    1995-01-01

    The Interstellar Medium (ISM) forms an integral part of the lifecycle of stars and the galaxy. Stars are formed by gravitational contraction of interstellar clouds. Over their life, stars return much of their mass to the ISM through winds and supernova explosions, resulting in a slow enrichment in heavy elements. Understanding the origin and evolution of the ISM is a key problem within astrophysics. The KAO has made many important contributions to studies of the interstellar medium both on the macro and on the micro scale. In this overview, I will concentrate on two breakthroughs in the last decade in which KAO observations have played a major role: (1) the importance of large Polycyclic Aromatic Hydrocarbon (PAH) molecules for the ISM (section 3) and (2) the study of Photodissociation Regions (PDRs) as an analog for the diffuse ISM at large (section 4). Appropriately, the micro and macro problem are intricately interwoven in these problems. Finally, section 5 reviews the origin of the (CII) emission observed by COBE.

  12. Common medium versus advanced IVF medium for cryopreserved oocytes in heterologous cycles.

    PubMed

    Poverini, R; Lisi, R; Lisi, F; Berlinghieri, V; Bielli, W; Carfagna, P; Costantino, A; Iacomino, D; Nicodemo, G

    2018-12-01

    Granulocyte-macrophage colony-stimulation factor plays different crucial roles during embryo implantation and subsequent development. Here we aimed to evaluate the effects of embryo cell culture medium, with the inclusion of granulocyte-macrophage colony-stimulation factor (GM-CSF), on embryo development and pregnancy rate. To this end, we took advantage of our retrospective observational study to correlate the outcomes from two different culture media. We included in this study 25 unselected patient from our IVF Center that underwent heterologous IVF cycle with crypreserved oocytes. We analyze the fertilization rate, pregnancy rate, and embryo quality at different day of transfer obtained from two different media composition. Our results show that the rate of fertilization and the pregnancy rate were increased using medium added with this particular type of cytokines (GM-CSF).

  13. Buoyant triacylglycerol-filled green algae and methods therefor

    DOEpatents

    Goodenough, Ursula; Goodson, Carrie

    2015-04-14

    Cultures of Chlamydomonas are disclosed comprising greater than 340 mg/l triacylglycerols (TAG). The cultures can include buoyant Chlamydomonas. Methods of forming the cultures are also disclosed. In some embodiments, these methods comprise providing Chlamydomonas growing in log phase in a first culture medium comprising a nitrogen source and acetate, replacing the first culture medium with a second medium comprising acetate but no nitrogen source, and subsequently supplementing the second medium with additional acetate. In some embodiments, a culture can comprise at least 1,300 mg/l triacyglycerols. In some embodiments, cultures can be used to produce a biofuel such as biodiesel.

  14. Training Children in Pedestrian Safety: Distinguishing Gains in Knowledge from Gains in Safe Behavior

    PubMed Central

    McClure, Leslie A.

    2014-01-01

    Pedestrian injuries contribute greatly to child morbidity and mortality. Recent evidence suggests that training within virtual pedestrian environments may improve children’s street crossing skills, but may not convey knowledge about safety in street environments. We hypothesized that (a) children will gain pedestrian safety knowledge via videos/software/internet websites, but not when trained by virtual pedestrian environment or other strategies; (b) pedestrian safety knowledge will be associated with safe pedestrian behavior both before and after training; and (c) increases in knowledge will be associated with increases in safe behavior among children trained individually at streetside locations, but not those trained by means of other strategies. We analyzed data from a randomized controlled trial evaluating pedestrian safety training. We randomly assigned 240 children ages 7–8 to one of four training conditions: videos/software/internet, virtual reality (VR), individualized streetside instruction, or a no-contact control. Both virtual and field simulations of street crossing at 2-lane bi-directional mid-block locations assessed pedestrian behavior at baseline, post-training, and 6-month follow-up. Pedestrian knowledge was assessed orally on all three occasions. Children trained by videos/software/internet, and those trained individually, showed increased knowledge following training relative to children in the other groups (ps < 0.01). Correlations between pedestrian safety knowledge and pedestrian behavior were mostly non-significant. Correlations between change in knowledge and change in behavior from pre- to post-intervention also were non-significant, both for the full sample and within conditions. Children trained using videos/software/internet gained knowledge but did not change their behavior. Children trained individually gained in both knowledge and safer behavior. Children trained virtually gained in safer behavior but not knowledge. If VR is used

  15. High-Gain High-Field Fusion Plasma

    PubMed Central

    Li, Ge

    2015-01-01

    A Faraday wheel (FW)—an electric generator of constant electrical polarity that produces huge currents—could be implemented in an existing tokamak to study high-gain high-field (HGHF) fusion plasma, such as the Experimental Advanced Superconducting Tokamak (EAST). HGHF plasma can be realized in EAST by updating its pulsed-power system to compress plasma in two steps by induction fields; high gains of the Lawson trinity parameter and fusion power are both predicted by formulating the HGHF plasma. Both gain rates are faster than the decrease rate of the plasma volume. The formulation is checked by earlier ATC tests. Good agreement between theory and tests indicates that scaling to over 10 T at EAST may be possible by two-step compressions with a compression ratio of the minor radius of up to 3. These results point to a quick new path of fusion plasma study, i.e., simulating the Sun by EAST. PMID:26507314

  16. CHROMagar Orientation Medium Reduces Urine Culture Workload

    PubMed Central

    Manickam, Kanchana; Karlowsky, James A.; Adam, Heather; Lagacé-Wiens, Philippe R. S.; Rendina, Assunta; Pang, Paulette; Murray, Brenda-Lee

    2013-01-01

    Microbiology laboratories continually strive to streamline and improve their urine culture algorithms because of the high volumes of urine specimens they receive and the modest numbers of those specimens that are ultimately considered clinically significant. In the current study, we quantitatively measured the impact of the introduction of CHROMagar Orientation (CO) medium into routine use in two hospital laboratories and compared it to conventional culture on blood and MacConkey agars. Based on data extracted from our Laboratory Information System from 2006 to 2011, the use of CO medium resulted in a 28% reduction in workload for additional procedures such as Gram stains, subcultures, identification panels, agglutination tests, and biochemical tests. The average number of workload units (one workload unit equals 1 min of hands-on labor) per urine specimen was significantly reduced (P < 0.0001; 95% confidence interval [CI], 0.5326 to 1.047) from 2.67 in 2006 (preimplementation of CO medium) to 1.88 in 2011 (postimplementation of CO medium). We conclude that the use of CO medium streamlined the urine culture process and increased bench throughput by reducing both workload and turnaround time in our laboratories. PMID:23363839

  17. Meaningful Reading Gains by Adult Literacy Learners

    ERIC Educational Resources Information Center

    Scarborough, Hollis S.; Sabatini, John P.; Shore, Jane; Cutting, Laurie E.; Pugh, Kenneth; Katz, Leonard

    2013-01-01

    To obtain a fuller picture of the efficacy of reading instruction programs for adult literacy learners, gains by individual students were examined in a sample (n = 148) in which weak to moderate gains at the group level had been obtained in response to tutoring interventions that focused on strengthening basic decoding and fluency skills of low…

  18. Sudden gains in group cognitive-behavioral therapy for panic disorder.

    PubMed

    Clerkin, Elise M; Teachman, Bethany A; Smith-Janik, Shannan B

    2008-11-01

    The current study investigates sudden gains (rapid symptom reduction) in group cognitive-behavioral therapy for panic disorder. Sudden gains occurring after session 2 of treatment predicted overall symptom reduction at treatment termination and some changes in cognitive biases. Meanwhile, sudden gains occurring immediately following session 1 were not associated with symptom reduction or cognitive change. Together, this research points to the importance of examining sudden gains across the entire span of treatment, as well as the potential role of sudden gains in recovery from panic disorder.

  19. Highly selective medium for isolation of Listeria monocytogenes from food.

    PubMed Central

    al-Zoreky, N; Sandine, W E

    1990-01-01

    A new selective medium (Al-Zoreky-Sandine listeria medium [ASLM]) was formulated to recover Listeria monocytogenes from food specimens; the medium completely inhibited common food microflora. Recognition of Listeria colonies is evident by black discoloration of the medium due to esculin hydrolysis without need for special illuminating equipment. The medium contains acriflavin, ceftazidime, and moxalactam as selective agents. Compared with Listeria Selective Agar, ASLM was equally effective in recovering L. monocytogenes. However, ASLM inhibited micrococci, enterococci, and gram-negative bacteria, especially a strain that mimicked L. monocytogenes on Listeria Selective Agar. The new medium was able to recover heat injured cells with only 15% less count than the nonselective medium. Images PMID:2126701

  20. Method to prepare nanoparticles on porous mediums

    DOEpatents

    Vieth, Gabriel M [Knoxville, TN; Dudney, Nancy J [Oak Ridge, TN; Dai, Sheng [Knoxville, TN

    2010-08-10

    A method to prepare porous medium decorated with nanoparticles involves contacting a suspension of nanoparticles in an ionic liquid with a porous medium such that the particles diffuse into the pores of the medium followed by heating the resulting composition to a temperature equal to or greater than the thermal decomposition temperature of the ionic liquid resulting in the removal of the liquid portion of the suspension. The nanoparticles can be a metal, an alloy, or a metal compound. The resulting compositions can be used as catalysts, sensors, or separators.

  1. Compositions and methods comprising cellulase variants with reduced affinity to non-cellulosic materials

    DOEpatents

    Cascao-Pereira, Luis; Kaper, Thijs; Kelemen, Bradley R.; Liu, Amy D.

    2017-07-04

    The present disclosure relates to cellulase variants. In particular the present disclosure relates to cellulase variants having reduced binding to non-cellulosic materials. Also described are nucleic acids encoding the cellulase, compositions comprising said cellulase, methods of identifying cellulose variants and methods of using the compositions.

  2. Compositions and methods comprising cellulase variants with reduced affinity to non-cellulosic materials

    DOEpatents

    Cascao-Pereira, Luis G; Kaper, Thijs; Kelemen, Bradley R; Liu, Amy D

    2015-04-07

    The present disclosure relates to cellulase variants. In particular the present disclosure relates to cellulase variants having reduced binding to non-cellulosic materials. Also described are nucleic acids encoding the cellulase, compositions comprising said cellulase, methods of identifying cellulose variants and methods of using the compositions.

  3. Compositions and methods comprising cellulase variants with reduced affinity to non-cellulosic materials

    DOEpatents

    Cascao-Pereira, Luis G.; Kaper, Thijs; Kelemen, Bradley R; Liu, Amy D.

    2012-08-07

    The present disclosure relates to cellulase variants. In particular the present disclosure relates to cellulase variants having reduced binding to non-cellulosic materials. Also described are nucleic acids encoding the cellulase, compositions comprising said cellulase, methods of identifying cellulose variants and methods of using the compositions.

  4. Collector surface for a microwave tube comprising a carbon-bonded carbon-fiber composite

    DOEpatents

    Lauf, Robert J.; McMillan, April D.; Johnson, Arvid C.; Moorhead, Arthur J.

    1998-01-01

    In a microwave tube, an improved collector surface coating comprises a porous carbon composite material, preferably a carbon-bonded carbon fiber composite having a bulk density less than about 2 g/cc. Installation of the coating is readily adaptable as part of the tube manufacturing process.

  5. New medium for detection of esterase and gelatinase activity.

    PubMed

    Pácová, Z; Kocur, M

    1984-10-01

    A new medium was developed for detecting esterase and gelatinase activities in aerobic and facultatively anaerobic bacteria. The new medium was tested with various strains of bacteria and the results showed agreement between the reactions in the new medium and those obtained by conventional techniques. The new medium is more economical and may be used for a rapid differentiation of Serratia, Aeromonas and Vibrio species from biochemically similar bacteria.

  6. Effects of Device on Video Head Impulse Test (vHIT) Gain.

    PubMed

    Janky, Kristen L; Patterson, Jessie N; Shepard, Neil T; Thomas, Megan L A; Honaker, Julie A

    2017-10-01

    Numerous video head impulse test (vHIT) devices are available commercially; however, gain is not calculated uniformly. An evaluation of these devices/algorithms in healthy controls and patients with vestibular loss is necessary for comparing and synthesizing work that utilizes different devices and gain calculations. Using three commercially available vHIT devices/algorithms, the purpose of the present study was to compare: (1) horizontal canal vHIT gain among devices/algorithms in normal control subjects; (2) the effects of age on vHIT gain for each device/algorithm in normal control subjects; and (3) the clinical performance of horizontal canal vHIT gain between devices/algorithms for differentiating normal versus abnormal vestibular function. Prospective. Sixty-one normal control adult subjects (range 20-78) and eleven adults with unilateral or bilateral vestibular loss (range 32-79). vHIT was administered using three different devices/algorithms, randomized in order, for each subject on the same day: (1) Impulse (Otometrics, Schaumberg, IL; monocular eye recording, right eye only; using area under the curve gain), (2) EyeSeeCam (Interacoustics, Denmark; monocular eye recording, left eye only; using instantaneous gain), and (3) VisualEyes (MicroMedical, Chatham, IL, binocular eye recording; using position gain). There was a significant mean difference in vHIT gain among devices/algorithms for both the normal control and vestibular loss groups. vHIT gain was significantly larger in the ipsilateral direction of the eye used to measure gain; however, in spite of the significant mean differences in vHIT gain among devices/algorithms and the significant directional bias, classification of "normal" versus "abnormal" gain is consistent across all compared devices/algorithms, with the exception of instantaneous gain at 40 msec. There was not an effect of age on vHIT gain up to 78 years regardless of the device/algorithm. These findings support that vHIT gain is

  7. The eightfold way model, the SU(3)-flavor model and the medium-strong interaction

    NASA Astrophysics Data System (ADS)

    Abbas, Syed Afsar

    2015-04-01

    Lack of any baryon number in the eightfold way model, and its intrinsic presence in the SU(3)-flavor model, has been a puzzle since the genesis of these models in 1961-1964. First we show that the conventional popular understanding of this puzzle is actually fundamentally wrong, and hence the problem being so old, begs urgently for resolution. In this paper we show that the issue is linked to the way that the adjoint representation is defined mathematically for a Lie algebra, and how it manifests itself as a physical representation. This forces us to distinguish between the global and the local charges and between the microscopic and the macroscopic models. As a bonus, a consistent understanding of the hitherto mysterious medium-strong interaction is achieved. We also gain a new perspective on how confinement arises in quantum chromodynamics.

  8. A dedicated AMS setup for medium mass isotopes at the Cologne FN tandem accelerator

    NASA Astrophysics Data System (ADS)

    Schiffer, M.; Altenkirch, R.; Feuerstein, C.; Müller-Gatermann, C.; Hackenberg, G.; Herb, S.; Bhandari, P.; Heinze, S.; Stolz, A.; Dewald, A.

    2017-09-01

    AMS measurements of medium mass isotopes, e.g. of 53Mn and 60Fe, are gaining interest in various fields of operation, especially geoscience. Therefore a dedicated AMS setup has been built at the Cologne 10 MV FN tandem accelerator. This setup is designed to obtain a sufficient suppression of the stable isobars at energies around 100 MeV. In this contribution we report on the actual status of the new setup and the first in-beam tests of its individual components. The isobar suppression is done with (dE/dx) techniques using combinations of energy degrader foils with an electrostatic analyzer (ESA) and a time of flight (ToF) system, as well as a (dE/dx),E gas ionization detector. Furthermore, the upgraded ion source and its negative ion yield measurement for MnO- are presented.

  9. 26 CFR 1.1247-3 - Treatment of capital gains.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 11 2010-04-01 2010-04-01 true Treatment of capital gains. 1.1247-3 Section 1... (CONTINUED) INCOME TAXES Special Rules for Determining Capital Gains and Losses § 1.1247-3 Treatment of capital gains. (a) Treatment by the company—(1) In general. If an election to distribute income currently...

  10. Sudden Gains in Group Cognitive-Behavioral Therapy for Panic Disorder

    PubMed Central

    Clerkin, Elise M.; Teachman, Bethany A.; Smith-Janik, Shannan B.

    2008-01-01

    The current study investigates sudden gains (rapid symptom reduction) in group cognitive-behavioral therapy for panic disorder. Sudden gains occurring after session 2 of treatment predicted overall symptom reduction at treatment termination and some changes in cognitive biases. Meanwhile, sudden gains occurring immediately following session 1 were not associated with symptom reduction or cognitive change. Together, this research points to the importance of examining sudden gains across the entire span of treatment, as well as the potential role of sudden gains in recovery from panic disorder. PMID:18804199

  11. Photonuclear activation of pure isotopic mediums.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Grohman, Mark A.; Lukosi, Eric Daniel

    2010-06-01

    This work simulated the response of idealized isotopic U-235, U-238, Th-232, and Pu-239 mediums to photonuclear activation with various photon energies. These simulations were conducted using MCNPX version 2.6.0. It was found that photon energies between 14-16 MeV produce the highest response with respect to neutron production rates from all photonuclear reactions. In all cases, Pu-239 responds the highest, followed by U-238. Th-232 produces more overall neutrons at lower photon energies then U-235 when material thickness is above 3.943 centimeters. The time it takes each isotopic material to reach stable neutron production rates in time is directly proportional to themore » material thickness and stopping power of the medium, where thicker mediums take longer to reach stable neutron production rates and thinner media display a neutron production plateau effect, due to the lack of significant attenuation of the activating photons in the isotopic mediums. At this time, no neutron sensor system has time resolutions capable of verifying these simulations, but various indirect methods are possible and should be explored for verification of these results.« less

  12. Phase object retrieval through scattering medium

    NASA Astrophysics Data System (ADS)

    Zhao, Ming; Zhao, Meijing; Wu, Houde; Xu, Wenhai

    2018-05-01

    Optical imaging through a scattering medium has been an interesting and important research topic, especially in the field of biomedical imaging. However, it is still a challenging task due to strong scattering. This paper proposes to recover the phase object behind the scattering medium from one single-shot speckle intensity image using calibrated transmission matrices (TMs). We construct the forward model as a non-linear mapping, since the intensity image loses the phase information, and then a generalized phase retrieval algorithm is employed to recover the hidden object. Moreover, we show that a phase object can be reconstructed with a small portion of the speckle image captured by the camera. The simulation is performed to demonstrate our scheme and test its performance. Finally, a real experiment is set up, we measure the TMs from the scattering medium, and then use it to reconstruct the hidden object. We show that a phase object of size 32 × 32 is retrieved from 150 × 150 speckle grains, which is only 1/50 of the speckles area. We believe our proposed method can benefit the community of imaging through the scattering medium.

  13. Concept for an off-line gain stabilisation method.

    PubMed

    Pommé, S; Sibbens, G

    2004-01-01

    Conceptual ideas are presented for an off-line gain stabilisation method for spectrometry, in particular for alpha-particle spectrometry at low count rate. The method involves list mode storage of individual energy and time stamp data pairs. The 'Stieltjes integral' of measured spectra with respect to a reference spectrum is proposed as an indicator for gain instability. 'Exponentially moving averages' of the latter show the gain shift as a function of time. With this information, the data are relocated stochastically on a point-by-point basis.

  14. Characterization of Residual Medium Peptides from Yersinia pestis Cultures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Clowers, Brian H.; Wunschel, David S.; Kreuzer, Helen W.

    2013-04-03

    Using a range of common microbial medium formulations (TSB, BHI, LB, and G-media), two attenuated strains of Y. pestis (KIM D27 (pgm-) and KIMD1 lcr-) were cultivated in triplicate. These cellular suspensions were used to develop a method of extracting residual medium peptides from the final microbial preparation to assess their relative abundance and identity. Across the conditions examined, which included additional cellular washing and different forms of microbial inactivation, residual medium peptides were detected. Despite the range of growth medium sources used and the associated manufacturing processes used in their production, a high degree of peptide similarity was observedmore » for a given medium recipe. These results demonstrate that residual medium peptides are retained using traditional microbial cultivation techniques and may be used to inform forensic investigations with respect to production deduction.« less

  15. Characterising the Circum-Galactic Medium of Damped Lyman-α Absorbing Galaxies

    NASA Astrophysics Data System (ADS)

    Augustin, Ramona; Péroux, Céline; Møller, Palle; Kulkarni, Varsha; Rahmani, Hadi; Milliard, Bruno; Pieri, Matthew; York, Donald G.; Vladilo, Giovanni; Aller, Monique; Zwaan, Martin

    2018-05-01

    Gas flows in and out of galaxies through their circumgalactic medium (CGM) are poorly constrained and direct observations of this faint, diffuse medium remain challenging. We use a sample of five z ˜ 1-2 galaxy counterparts to Damped Lyman-α Absorbers (DLAs) to combine data on cold gas, metals and stellar content of the same galaxies. We present new HST/WFC3 imaging of these fields in 3-5 broadband filters and characterise the stellar properties of the host galaxies. By fitting the spectral energy distribution, we measure their stellar masses to be in the range of log(M*/M⊙) ˜ 9.1-10.7. Combining these with IFU observations, we find a large spread of baryon fractions inside the host galaxies, between 7 and 100 percent. Similarly, we find gas fractions between 3 and 56 percent. Given their star formation rates, these objects lie on the expected main sequence of galaxies. Emission line metallicities indicate they are consistent with the mass-metallicity relation for DLAs. We also report an apparent anti-correlation between the stellar masses and N(H I), which could be due to a dust bias effect or lower column density systems tracing more massive galaxies. We present new ALMA observations of one of the targets leading to a molecular gas mass of log(Mmol/M⊙) < 9.89. We also investigate the morphology of the DLA counterparts and find that most of the galaxies show a clumpy structure and suggest ongoing tidal interaction. Thanks to our high spatial resolution HST data, we gain new insights in the structural complexity of the CGM.

  16. In-medium properties of mesons

    NASA Astrophysics Data System (ADS)

    Metag, Volker; Nanova, Mariana; Brinkmann, Kai-Thomas

    2017-01-01

    In the project B.4, the modification of meson properties (mass, width) in a nuclear medium has been studied in photoproduction of mesons off nuclear targets. This work has been motivated by theoretical expectations of in-medium modifications of hadrons based on the conjecture of a partial restoration of chiral symmetry in a strongly interacting medium. It has been shown that these in-medium changes can be discussed in a compact form in terms of an optical potential describing the meson-nucleus interaction. Experimental approaches to determine the real and imaginary part of the meson-nucleus potential have been developed. The experiments have been performed with the Crystal Barrel/TAPS detector at the electron accelerator ELSA (Bonn) and the Crystal Ball/TAPS detector at MAMI (Mainz). Measuring the excitation function and momentum distribution for photo production of ω and η' mesons, the real parts of the ω and η'-nucleus potential, given by the in-medium mass shift, have been determined. For the η' meson a lowering of the mass at normal nuclear matter density by -(39±7(stat)±15(syst)) MeV is observed, while for the ω meson a slightly smaller mass shift is found, however, with much larger uncertainties, not excluding a zero mass shift. The imaginary part of the potentials has been extracted from the measurement of the transparency ratio which compares the meson production cross section per nucleon within a nucleus to the production cross section off the free proton. For the η' meson the imaginary part of the potential is found to be smaller than the real part. In case of the ω meson the opposite is observed. This makes the η' meson a good candidate for the search for meson-nucleus bound states while no resolved ω mesic states can be expected. The results are compared with theoretical predictions. An outlook on future experiments is given.

  17. Study of gain homogeneity and radiation effects of Low Gain Avalanche Pad Detectors

    NASA Astrophysics Data System (ADS)

    Gallrapp, C.; Fernández García, M.; Hidalgo, S.; Mateu, I.; Moll, M.; Otero Ugobono, S.; Pellegrini, G.

    2017-12-01

    Silicon detectors with intrinsic charge amplification implementing a n++-p+-p structure are considered as a sensor technology for future tracking and timing applications in high energy physics experiments. The performance of the intrinsic gain in Low Gain Avalanche Detectors (LGAD) after irradiation is crucial for the characterization of radiation hardness and timing properties in this technology. LGAD devices irradiated with reactor neutrons or 800 MeV protons reaching fluences of 2.3 × 1016 neq/cm2 were characterized using Transient Current Technique (TCT) measurements with red and infra-red laser pulses. Leakage current variations observed in different production lots and within wafers were investigated using Thermally Stimulated Current (TSC). Results showed that the intrinsic charge amplification is reduced with increasing fluence up to 1015 neq/cm2 which is related to an effective acceptor removal. Further relevant issues were charge collection homogeneity across the detector surface and leakage current performance before and after irradiation.

  18. The bias in current measures of gestational weight gain

    PubMed Central

    Hutcheon, Jennifer A; Bodnar, Lisa M; Joseph, KS; Abrams, Barbara; Simhan, Hyagriv N; Platt, Robert W

    2014-01-01

    Summary Conventional measures of gestational weight gain (GWG), such as average rate of weight gain, are likely correlated with gestational duration. Such correlation could introduce bias to epidemiologic studies of GWG and adverse perinatal outcomes because many perinatal outcomes are also correlated with gestational duration. This study aimed to quantify the extent to which currently-used GWG measures may bias the apparent relation between maternal weight gain and risk of preterm birth. For each woman in a provincial perinatal database registry (British Columbia, Canada, 2000–2009), a total GWG was simulated such that it was uncorrelated with risk of preterm birth. The simulation was based on serial antenatal GWG measurements from a sample of term pregnancies. Simulated GWGs were classified using 3 approaches: total weight gain (kg), average rate of weight gain (kg/week) or adequacy of gestational weight gain in relation to Institute of Medicine recommendations, and their association with preterm birth ≤ 32 weeks was explored using logistic regression. All measures of GWG induced an apparent association between GWG and preterm birth ≤32 weeks even when, by design, none existed. Odds ratios in the lowest fifths of each GWG measure compared with the middle fifths ranged from 4.4 [95% CI 3.6, 5.4] (total weight gain) to 1.6 [95% CI 1.3, 2.0] (Institute of Medicine adequacy ratio). Conventional measures of GWG introduce serious bias to the study of maternal weight gain and preterm birth. A new measure of GWG that is uncorrelated with gestational duration is needed. PMID:22324496

  19. Collector surface for a microwave tube comprising a carbon-bonded carbon-fiber composite

    DOEpatents

    Lauf, R.J.; McMillan, A.D.; Johnson, A.C.; Moorhead, A.J.

    1998-07-28

    In a microwave tube, an improved collector surface coating comprises a porous carbon composite material, preferably a carbon-bonded carbon fiber composite having a bulk density less than about 2 g/cc. Installation of the coating is readily adaptable as part of the tube manufacturing process. 4 figs.

  20. Spontaneous physical activity protects against fat mass gain

    PubMed Central

    Teske, Jennifer A.; Billington, Charles J.; Kuskowski, Michael A.; Kotz, Catherine M.

    2011-01-01

    It is unclear whether elevated spontaneous physical activity (SPA, very low-intensity physical activity) positively influences body composition long-term. Objective We determined whether SPA and caloric intake were differentially related to the growth curve trajectories of body weight, FM and FFM between obesity resistant and Sprague-Dawley rats at specific age intervals. Design and Subjects Body composition, SPA and caloric intake were measured in selectively-bred obesity resistant and out-bred Sprague-Dawley rats from 1-18 mo. Data from development throughout maturation were analyzed by longitudinal growth curve modeling to determine the rate and acceleration of body weight, fat mass (FM) and fat-free mass (FFM) gain. Results Obesity resistant rats had a lower rate of FM gain overall, a lower acceleration in body weight early in life, significantly greater SPA and lower cumulative caloric intake. Greater SPA in obesity resistant rats was significantly associated with a lower rate of FM gain overall and lower acceleration in body weight early in life. Obesity resistant rats lost less FFM compared to Sprague-Dawley rats despite that obesity resistant rats had a lower acceleration in FFM gain early in life. Obesity resistant rats gained less FM and more FFM per gram body weight and were less energy efficient than Sprague-Dawley rats. Caloric intake was significantly and positively related to body weight, FM and FFM gain in both groups. Circadian patterns of caloric intake were group and age-dependent. Our data demonstrate that elevated and sustained SPA during development and over the lifespan are related to the reduced the rate of FM gain and may preserve FFM. Conclusion These data support the idea that SPA level is a reproducible marker that reliably predicts propensity for obesity in rats, and that elevated levels of SPA maintained during the lifespan promote a lean phenotype. PMID:21610695