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Sample records for ca ii triplet

  1. Detection of Ca II absorption triplet in a circumnuclear H II region of NGC 3310

    OpenAIRE

    Terlevich, Elena; Angeles I. Díaz; Pastoriza, Miriani G.; Terlevich, Roberto; Dottori, Horacio

    1990-01-01

    This is an electronic version of an article published in Monthly Notices of the Royal Astronomical Society. Terlevich, E., Díaz, A.I., Pastoriza, M.G., Terlevich, R. and H. Dottori. Detection of Ca II absorption triplet in a circumnuclear H II region of NGC 3310. Monthly Notices of the Royal Astronomical Society 242 (1990): 48-51

  2. Detection of Ca II absorption triplet in a circumnuclear H II region of NGC 3310

    International Nuclear Information System (INIS)

    We have obtained long slit spectrophotometry across NGC 3310, a luminous galaxy with circumnuclear bursts of star formation, covering the spectral range from λ3650 to 9700 A. In one giant star-forming region, the near-IR Ca II absorption lines (a signature of young supergiants) was detected with a strength similar to that of the nuclear region. This is, to our knowledge, the first detection of the IR Ca II triplet in an extragalactic giant H II region and confirms theoretical predictions that, after some 4 Myr, red supergiants should appear in bursts of star formation. (author)

  3. On the behaviour of the IR Ca II triplet in normal and active galaxies

    International Nuclear Information System (INIS)

    Ca II triplet in absorption at λλ8498,8542,8662 A is the strongest feature in the infrared spectrum of late-type stars and normal galaxies. Its strength has been found to be a good luminosity indicator for metal-rich stellar populations. We present high signal-to-noise near-IR spectroscopic data for the nuclear region of 42 normal and active galaxies. We have explored the behaviour of the Ca II triplet strength and found that it shows a small spread around a mean value of 7 A for our sample of normal galaxies. We also found that, in all the Seyfert type 2 galaxies measured and even in some Seyfert type 1, while the optical stellar features show substantial dilution, the strength of the IR Ca II triplet is equal to and in some cases larger than that in normal elliptical galaxies. (author)

  4. On the behaviour of the IR Ca II triplet in normal and active galaxies

    OpenAIRE

    Terlevich, Elena; Angeles I. Díaz; Terlevich, Roberto

    1990-01-01

    This is an electronic version of an article published in Monthly Notices of the Royal Astronomical Society. Terlevich, E., Díaz, A.I., Terlevich, R. On the behaviour of the IR Ca II triplet in normal and active galaxies. Monthly Notices of the Royal Astronomical Society 242 (1990): 271-284

  5. The Ca II triplet in red giant spectra: [Fe/H] determinations and the role of [Ca/Fe

    CERN Document Server

    Da Costa, G S

    2015-01-01

    Measurements are presented and analyzed of the strength of the Ca II triplet lines in red giants in Galactic globular and open clusters, and in a sample of red giants in the LMC disk that have significantly different [Ca/Fe] abundance ratios to the Galactic objects. The Galactic objects are used to generate a calibration between Ca II triplet line strength and [Fe/H], which is then used to estimate [Fe/H]_CaT for the LMC stars. The values are then compared with the [Fe/H]_spec determinations from high dispersion spectroscopy. After allowance for a small systematic offset the two abundance determinations are in excellent agreement. Further, as found in earlier studies, e.g., Battaglia et al. (2008), the difference is only a very weak function of the [Ca/Fe] ratio. For example, changing [Ca/Fe] from +0.3 to -0.2 causes the Ca II based abundance to underestimate [Fe/H]_spec by only ~0.15 dex, assuming a Galactic calibration. Consequently, the Ca II triplet approach to metallicity determinations can be used witho...

  6. Empirical calibration of the near-IR Ca II triplet - III. Fitting functions

    CERN Document Server

    Cenarro, A J; Cardiel, N; Vazdekis, A; Peletier, R F

    2001-01-01

    Using a near-IR stellar library of 706 stars with a wide coverage of atmospheric parameters, we study the behaviour of the Ca II triplet strength in terms of effective temperature, surface gravity and metallicity. Empirical fitting functions for recently defined line-strength indices, namely CaT*, CaT and PaT, are provided. These functions can be easily implemented into stellar populations models to provide accurate predictions for integrated Ca II strengths. We also present a thorough study of the various error sources and their relation to the residuals of the derived fitting functions. Finally, the derived functional forms and the behaviour of the predicted Ca II are compared with those of previous works in the field.

  7. Measurements of Ca II Infrared Triplet Lines of Young Stellar Objects

    CERN Document Server

    Moto'oka, Keiko

    2015-01-01

    Equivalent widths and line widths of Ca II infrared triplet emission lines were measured in high-resolution optical spectra of 39 young stellar objects.We found that the equivalent widths of the emission lines decrease with stellar evolution. It has been often claimed that strong chromospheric activity is generated by a dynamo process caused by fast rotation of the photosphere. However, we found no clear correlation between the strength of the Ca II lines and the stellar rotation velocity. Instead, we found that the objects with high mass accretion rates had stronger Ca II emission lines. This correlation supports the turbulent chromosphere model or the magnetic accretion theory for classical T Tauri stars. We also noticed that the equivalent widths of Ca II lines of transitional disk objects are one-tenth of those of classical T Tauri stars, even if the masses of the circumstellar disks are comparable.

  8. Low Ionization Emission Lines in Quasars: Clues from OI 8446 and the CaII Triplet

    OpenAIRE

    Marziani, Paola; Martinez-Aldama, Mary Loli; Dultzin, Deborah; Sulentic, Jack

    2013-01-01

    The formation of low emission lines in quasars and active galactic nuclei is still an open issue. Aided by the organizing power of the 4D eigenvector 1 scheme, we review basic developments since the 1980s, devoting special attention to the CaII IR triplet and the OI 8446 emission lines. Coverage of these lines is cumbersome since they are shifted in an inconvenient IR domain already at modest redshifts (~ 0.2). Their detection is also difficult since they are faint and often buried in the Ca ...

  9. Low Ionization Emission Lines in Quasars: Clues from OI 8446 and the CaII Triplet

    CERN Document Server

    Marziani, Paola; Dultzin, Deborah; Sulentic, Jack

    2013-01-01

    The formation of low emission lines in quasars and active galactic nuclei is still an open issue. Aided by the organizing power of the 4D eigenvector 1 scheme, we review basic developments since the 1980s, devoting special attention to the CaII IR triplet and the OI 8446 emission lines. Coverage of these lines is cumbersome since they are shifted in an inconvenient IR domain already at modest redshifts (~ 0.2). Their detection is also difficult since they are faint and often buried in the Ca II absorption of the host galaxy. We discuss how these lines can provide unambiguous constraints on the physical conditions of the broad line emitting regions of quasars when detected in emission, and summarise preliminary results for a sample of luminous, intermediate redshift quasars.

  10. Automatic stellar spectra parameterisation in the IR CaII triplet region

    CERN Document Server

    Kordopatis, G; de Laverny, P; Bijaoui, A; Hill, V; Gilmore, G; Wyse, R F G; Ordenovic, C

    2011-01-01

    (Abridged) Galactic archaeology aims to determine the evolution of the Galaxy from the chemical and kinematical properties of its stars. The analysis of current large spectroscopic surveys (thousands of stars) and future ones (millions of stars) require automated analysis techniques to obtain robust estimates of the stellar parameters. Several on-going and planned spectroscopic surveys have selected their wavelength region to contain the IR CaII triplet and this paper focuses on the automatic analysis of such spectra. We investigated two algorithms, MATISSE and DEGAS, both of which compare the observed spectrum to a grid of synthetic spectra, but each uses a different mathematical approach for finding the optimum match and hence the best stellar parameters. We identified degeneracies in different regions of the HR diagram: hot dwarfs and giants share the same spectral signatures. Furthermore, the surface gravity of cooler dwarfs is difficult to determine accurately. These effects are intensified when the info...

  11. Study of the Sextans dwarf spheroidal galaxy from the DART CaII triplet survey

    CERN Document Server

    Battaglia, G; Helmi, A; Irwin, M; Parisi, P; Hill, V; Jablonka, P

    2010-01-01

    We use VLT/FLAMES intermediate resolution (R~6500) spectra of individual red giant branch stars in the near-infrared CaII triplet (CaT) region to investigate the wide-area metallicity properties and internal kinematics of the Sextans dwarf spheroidal galaxy (dSph). Our final sample consists of 174 probable members of Sextans with accurate line-of-sight velocities (+- 2 km/s) and CaT [Fe/H] measurements (+- 0.2 dex). We use the MgI line at 8806.8 \\AA\\, as an empirical discriminator for distinguishing between probable members of the dSph (giant stars) and probable Galactic contaminants (dwarf stars). Sextans shows a similar chemo-dynamical behaviour to other Milky Way dSphs, with its central regions being more metal rich than the outer parts and with the more metal-rich stars displaying colder kinematics than the more metal-poor stars. Hints of a velocity gradient are found along the projected major axis and along an axis at P.A.=191 deg, however a larger and more spatially extended sample may be necessary to p...

  12. Ca II triplet spectroscopy of RGB stars in NGC 6822: kinematics and metallicities

    CERN Document Server

    Swan, Jesse; Tolstoy, Eline; Irwin, Mike J

    2016-01-01

    We present a detailed analysis of the chemistry and kinematics of red giants in the dwarf irregular galaxy NGC 6822. Spectroscopy at 8500 Angstroms was acquired for 72 red giant stars across two fields using FORS2 at the VLT. Line of sight extinction was individually estimated for each target star to accommodate the variable reddening across NGC 6822. The mean radial velocity was found to be v_helio = (52.8 +/- 2.2) km/s with dispersion rms = 24.1 km/s, in agreement with other studies. Ca II triplet equivalent widths were converted into [Fe/H] metallicities using a V magnitude proxy for surface gravity. The average metallicity was [Fe/H] = (-0.84 +/- 0.04) with dispersion rms = 0.31 dex and interquartile range 0.48. Our assignment of individual reddening values makes our analysis more sensitive to spatial variations in metallicity than previous studies. We divide our sample into metal-rich and metal-poor stars; the former are found to cluster towards small radii with the metal-poor stars more evenly distribut...

  13. Ca II triplet spectroscopy of RGB stars in NGC 6822: kinematics and metallicities

    Science.gov (United States)

    Swan, J.; Cole, A. A.; Tolstoy, E.; Irwin, M. J.

    2016-03-01

    We present a detailed analysis of the chemistry and kinematics of red giants in the dwarf irregular galaxy NGC 6822. Spectroscopy at ≈8500 Å was acquired for 72 red giant stars across two fields using FORS2 at the VLT. Line-of-sight extinction was individually estimated for each target star to accommodate the variable reddening across NGC 6822. The mean radial velocity was found to be = -52.8 ± 2.2 km s-1 with dispersion σv = 24.1 km s-1, in agreement with other studies. Ca II triplet equivalent widths were converted into [Fe/H] metallicities using a V magnitude proxy for surface gravity. The average metallicity was = -0.84 ± 0.04 with dispersion σ = 0.31 dex and interquartile range 0.48. Our assignment of individual reddening values makes our analysis more sensitive to spatial variations in metallicity than previous studies. We divide our sample into metal-rich and metal-poor stars; the former were found to cluster towards small radii with the metal-poor stars more evenly distributed across the galaxy. The velocity dispersion of the metal-poor stars was found to be higher than that of the metal-rich stars (σ _{v_MP}=27.4 km s-1; σ _{v_MR}=21.1 km s-1); combined with the age-metallicity relation this indicates that the older populations have either been dynamically heated during their lifetimes or were born in a less disc-like distribution than the younger stars.. The low ratio vrot/σv suggests that within the inner 10 arcmin, NGC 6822's stars are dynamically decoupled from the H I gas, and possibly distributed in a thick disc or spheroid structure.

  14. Ca II TRIPLET SPECTROSCOPY OF SMALL MAGELLANIC CLOUD RED GIANTS. II. ABUNDANCES FOR A SAMPLE OF FIELD STARS

    International Nuclear Information System (INIS)

    We have obtained metallicities of ∼360 red giant stars distributed in 15 Small Magellanic Cloud (SMC) fields from near-infrared spectra covering the Ca II triplet lines using the VLT + FORS2. The errors of the derived [Fe/H] values range from 0.09 to 0.35 dex per star, with a mean of 0.17 dex. The metallicity distribution (MD) of the whole sample shows a mean value of [Fe/H] = -1.00 ± 0.02, with a dispersion of 0.32 ± 0.01, in agreement with global mean [Fe/H] values found in previous studies. We find no evidence of a metallicity gradient in the SMC. In fact, on analyzing the MD of each field, we derived mean values of [Fe/H] = -0.99 ± 0.08 and [Fe/H] = -1.02 ± 0.07 for fields located closer and farther than 4 deg. from the center of the galaxy, respectively. In addition, there is a clear tendency for the field stars to be more metal-poor than the corresponding cluster they surround, independent of their positions in the galaxy and of the clusters' age. We argue that this most likely stems from the field stars being somewhat older and therefore somewhat more metal-poor than most of our clusters.

  15. Temporal Evolution of the Scattering Polarization of the CaII IR Triplet in Hydrodynamical Models of the Solar Chromosphere

    CERN Document Server

    Carlin, E S; Bueno, J Trujillo

    2012-01-01

    Velocity gradients in a stellar atmospheric plasma have an impact on the anisotropy of the radiation field that illuminates each point within the medium, and this may in principle influence the scattering line polarization that results from the induced atomic level polarization. Here we analyze the emergent linear polarization profiles of the Ca II infrared triplet after solving the radiative transfer problem of scattering polarization in time-dependent hydrodynamical models of the solar chromosphere, taking into account the impact of the plasma macroscopic velocity on the atomic level polarization. We discuss the influence that the velocity and temperature shocks in the considered chromospheric models have on the temporal evolution of the scattering polarization signals of the Ca II infrared lines, as well as on the temporally averaged profiles. Our results indicate that the increase of the linear polarization amplitudes caused by macroscopic velocity gradients may be significant in realistic situations. We ...

  16. Automatic stellar spectra parameterisation in the IR Ca ii triplet region

    Science.gov (United States)

    Kordopatis, G.; Recio-Blanco, A.; de Laverny, P.; Bijaoui, A.; Hill, V.; Gilmore, G.; Wyse, R. F. G.; Ordenovic, C.

    2011-11-01

    Context. Galactic archaeology aims to determine the evolution of the Galaxy from the chemical and kinematical properties of its individual stars. This requires the analysis of data from large spectroscopic surveys, with sample sizes in tens of thousands at present, with millions of stars being reached in the near future. Such large samples require automated analysis techniques and classification algorithms to obtain robust estimates of the stellar parameter values. Several on-going and planned spectroscopic surveys have selected their wavelength region to contain the IR Ca ii triplet (~λλ 8500 Å) and the work presented in this paper focuses on the automatic analysis of such spectra. Aims: We aim to develop and test an automatic method by which one can obtain estimates of values of the stellar atmospheric parameters (effective temperature, surface gravity, overall metallicity) from a stellar spectrum. We also explore the degeneracies in parameter space, estimate the uncertainties in the derived parameter values and investigate the consequences of these limitations for achieving the goals of galactic archaeology. Methods: We investigated two algorithms, both of which compare the observed spectrum to a grid of synthetic spectra, but each uses a different mathematical approach for finding the optimum match and hence the best values of the stellar parameters. Our investigation of these algorithms' robustness can be widely applied because it amplifies the main problems that the other methods can encounter. The first algorithm, MATISSE, derives the values of each stellar parameter through a local fit to the spectrum such that each pixel in wavelength space is treated separately. The sensitivity of the flux at each wavelength to the value of a given stellar parameter is determined from the synthetic spectra. The observed spectrum is then projected using these sensitivity vectors to give an estimated value of the stellar parameters. This value depends on finding the true

  17. Ca II Triplet Spectroscopy of Small Magellanic Cloud Red Giants. III. Abundances and Velocities for a Sample of 14 Clusters

    Science.gov (United States)

    Parisi, M. C.; Geisler, D.; Clariá, J. J.; Villanova, S.; Marcionni, N.; Sarajedini, A.; Grocholski, A. J.

    2015-05-01

    We obtained spectra of red giants in 15 Small Magellanic Cloud (SMC) clusters in the region of the Ca ii lines with FORS2 on the Very Large Telescope. We determined the mean metallicity and radial velocity with mean errors of 0.05 dex and 2.6 km s-1, respectively, from a mean of 6.5 members per cluster. One cluster (B113) was too young for a reliable metallicity determination and was excluded from the sample. We combined the sample studied here with 15 clusters previously studied by us using the same technique, and with 7 clusters whose metallicities determined by other authors are on a scale similar to ours. This compilation of 36 clusters is the largest SMC cluster sample currently available with accurate and homogeneously determined metallicities. We found a high probability that the metallicity distribution is bimodal, with potential peaks at -1.1 and -0.8 dex. Our data show no strong evidence of a metallicity gradient in the SMC clusters, somewhat at odds with recent evidence from Ca ii triplet spectra of a large sample of field stars. This may be revealing possible differences in the chemical history of clusters and field stars. Our clusters show a significant dispersion of metallicities, whatever age is considered, which could be reflecting the lack of a unique age-metallicity relation in this galaxy. None of the chemical evolution models currently available in the literature satisfactorily represents the global chemical enrichment processes of SMC clusters.

  18. Fine structure of the age-chromospheric activity relation in solar-type stars I: The Ca II infrared triplet: Absolute flux calibration

    CERN Document Server

    Lorenzo-Oliveira, Diego; Dutra-Ferreira, Letícia; Ribas, Ignasi

    2016-01-01

    Strong spectral lines are useful indicators of stellar chromospheric activity. They are physically linked to the convection efficiency, differential rotation, and angular momentum evolution and are a potential indicator of age. However, for ages > 2 Gyr, the age-activity relationship remains poorly constrained thus hampering its full application. The Ca II infrared triplet (IRT lines) has been poorly studied compared to classical chromospheric indicators. We report in this paper absolute chromospheric fluxes in the three Ca II IRT lines, based on a new calibration tied to up-to-date model atmospheres. We obtain the Ca II IRT absolute fluxes for 113 FGK stars from high signal-to-noise ratio and high-resolution spectra covering an extensive domain of chromospheric activity levels. We perform an absolute continuum flux calibration for the Ca II IRT lines anchored in atmospheric models calculated as an explicit function of effective temperatures, metallicity, and gravities avoiding the degeneracy present in photo...

  19. Radial velocities and metallicities from infrared Ca II triplet spectroscopy of open clusters II. Berkeley 23, King 1, NGC 559, NGC 6603 and NGC 7245

    CERN Document Server

    Carrera, R; Ospina, N; Balaguer-Nuñez, L; Jordi, C; Monteagudo, L

    2015-01-01

    Context: Open clusters are key to studying the formation and evolution of the Galactic disc. However, there is a deficiency of radial velocity and chemical abundance determinations for open clusters in the literature. Aims: We intend to increase the number of determinations of radial velocities and metallicities from spectroscopy for open clusters. Methods: We acquired medium-resolution spectra (R~8000) in the infrared region Ca II triplet lines (~8500 AA) for several stars in five open clusters with the long-slit IDS spectrograph on the 2.5~m Isaac Newton Telescope (Roque de los Muchachos Observatory, Spain). Radial velocities were obtained by cross-correlation fitting techniques. The relationships available in the literature between the strength of infrared Ca II lines and metallicity were also used to derive the metallicity for each cluster. Results: We obtain = 48.6+/-3.4, -58.4+/-6.8, 26.0+/-4.3 and -65.3+/-3.2 km s-1 for Berkeley 23, NGC 559, NGC 6603 and NGC 7245, respectively. We found [Fe/H] =-0.25+...

  20. Radial velocities and metallicities from infrared Ca ii triplet spectroscopy of open clusters. II. Berkeley 23, King 1, NGC 559, NGC 6603, and NGC 7245

    Science.gov (United States)

    Carrera, R.; Casamiquela, L.; Ospina, N.; Balaguer-Núñez, L.; Jordi, C.; Monteagudo, L.

    2015-06-01

    Context. Open clusters are key to studying the formation and evolution of the Galactic disc. However, there is a deficiency of radial velocity and chemical abundance determinations for open clusters in the literature. Aims: We intend to increase the number of determinations of radial velocities and metallicities from spectroscopy for open clusters. Methods: We acquired medium-resolution spectra (R ~ 8000) in the infrared region Ca ii triplet lines (~8500 Å) for several stars in five open clusters with the long-slit IDS spectrograph on the 2.5 m Isaac Newton Telescope (Roque de los Muchachos Observatory, Spain). Radial velocities were obtained by cross-correlation fitting techniques. The relationships available in the literature between the strength of infrared Ca ii lines and metallicity were also used to derive the metallicity for each cluster. Results: We obtain ⟨Vr⟩ = 48.6 ± 3.4, -58.4 ± 6.8, 26.0 ± 4.3, and -65.3 ± 3.2 km s-1 for Berkeley 23, NGC 559, NGC 6603, and NGC 7245, respectively. We found [ Fe/H ] = -0.25 ± 0.14 and -0.15 ± 0.18 for NGC 559 and NGC 7245, respectively. Berkeley 23 has low metallicity, [ Fe/H ] = -0.42 ± 0.13, which is similar to other open clusters in the outskirts of the Galactic disc. In contrast, we derived high metallicity ([ Fe/H ] = +0.43 ± 0.15) for NGC 6603, which places this system among the most metal-rich known open clusters. To our knowledge, this is the first determination of radial velocities and metallicities from spectroscopy for these clusters, except NGC 6603, for which radial velocities had been previously determined. We have also analysed ten stars in the line of sight to King 1. Because of the large dispersion obtained in both radial velocity and metallicity, we cannot be sure that we have sampled true cluster members. Based on observations made with the 2.5 m Isaac Newton Telescope operated on the island of La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the

  1. A new synthetic library of the Near-Infrared CaII triplet indices. I.Index Definition, Calibration and Relations with stellar atmospheric parameters

    CERN Document Server

    Du, Wei; Zhao, Yong-Heng

    2011-01-01

    Adopting the SPECTRUM package, we have synthesized a set of 2,890 Near-InfraRed (NIR) synthetic spectra with a resolution and wavelength sampling similar to the SDSS and the forthcoming LAMOST spectra. During the synthesis, we have applied the `New grids of ATLAS9 Model Atmosphere' to provide a grid of local thermodynamic equilibrium (LTE) model atmospheres. This synthetic stellar library is composed of 1,350 solor scaled abundance (SSA) and 1,530 non-solar scaled abundance (NSSA) spectra, grounding on which we have defined a new set of NIR CaII triplet indices and an index CaT as the sum of the three. Then, these defined indices have been automatically measured on the synthetic spectra and calibrated with the indices computed on the observational spectra from the INDO-U.S. stellar library. In order to check the effect of alpha-element enhancement on the so-defined CaII indices, we have compared indices measured on the SSA spectra with those on the NSSA ones at the same terns of stellar parameters (Teff, log ...

  2. A New Synthetic Library of the Near-infrared Ca II Triplet Indices. I. Index Definition, Calibration, and Relations with Stellar Atmospheric Parameters

    Science.gov (United States)

    Du, W.; Luo, A. L.; Zhao, Y. H.

    2012-02-01

    Adopting the SPECTRUM package, which is a stellar spectral synthesis program, we have synthesized a comprehensive set of 2890 near-infrared (NIR) synthetic spectra with a resolution and wavelength sampling similar to the Sloan Digital Sky Survey (SDSS) and the forthcoming Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) spectra. During the synthesis, we applied the "New grids of ATLAS9 Model Atmosphere" to develop a grid of local thermodynamic equilibrium model atmospheres for effective temperatures (T eff) ranging from 3500 to 7500 K, for surface gravities (log g) from 0.5 to 5.0 dex, for metallicities ([Fe/H]) from -4.0 to 0.5 dex, and for solar ([α/Fe] = 0.0 dex) and non-solar ([α/Fe] = +0.4 dex) abundances. This synthetic stellar library is composed of 1350 solar scaled abundance (SSA) and 1530 non-solar scaled abundance (NSSA) spectra, grounding on which we have defined a new set of NIR Ca II triplet indices and an index CaT as the sum of the three. These defined indices were automatically measured on every spectrum of the synthetic stellar library and calibrated with the indices computed on the observational spectra from the INDO-U.S. stellar library. In order to check the effect of α-element enhancement on the so-defined Ca II indices, we compared indices measured on the SSA spectra with those on the NSSA ones at the same trine of stellar parameters (T eff, log g, [Fe/H]); luckily, little influences of α-element enhancement were found. Furthermore, comparisons of our synthetic indices with the observational ones from measurements on the INDO-U.S. stellar library, the SDSS-DR7 and SDSS-DR8 spectroscopic survey are presented, respectively, for dwarfs and giants in specific. For dwarfs, our synthetic indices could well reproduce the behaviors of the observational indices versus stellar parameters, which verifies the validity of our index definitions for dwarfs. For giants, the consistency between our synthetic indices and the observational

  3. A NEW SYNTHETIC LIBRARY OF THE NEAR-INFRARED Ca II TRIPLET INDICES. I. INDEX DEFINITION, CALIBRATION, AND RELATIONS WITH STELLAR ATMOSPHERIC PARAMETERS

    International Nuclear Information System (INIS)

    Adopting the SPECTRUM package, which is a stellar spectral synthesis program, we have synthesized a comprehensive set of 2890 near-infrared (NIR) synthetic spectra with a resolution and wavelength sampling similar to the Sloan Digital Sky Survey (SDSS) and the forthcoming Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) spectra. During the synthesis, we applied the 'New grids of ATLAS9 Model Atmosphere' to develop a grid of local thermodynamic equilibrium model atmospheres for effective temperatures (Teff) ranging from 3500 to 7500 K, for surface gravities (log g) from 0.5 to 5.0 dex, for metallicities ([Fe/H]) from –4.0 to 0.5 dex, and for solar ([α/Fe] = 0.0 dex) and non-solar ([α/Fe] = +0.4 dex) abundances. This synthetic stellar library is composed of 1350 solar scaled abundance (SSA) and 1530 non-solar scaled abundance (NSSA) spectra, grounding on which we have defined a new set of NIR Ca II triplet indices and an index CaT as the sum of the three. These defined indices were automatically measured on every spectrum of the synthetic stellar library and calibrated with the indices computed on the observational spectra from the INDO-U.S. stellar library. In order to check the effect of α-element enhancement on the so-defined Ca II indices, we compared indices measured on the SSA spectra with those on the NSSA ones at the same trine of stellar parameters (Teff, log g, [Fe/H]); luckily, little influences of α-element enhancement were found. Furthermore, comparisons of our synthetic indices with the observational ones from measurements on the INDO-U.S. stellar library, the SDSS-DR7 and SDSS-DR8 spectroscopic survey are presented, respectively, for dwarfs and giants in specific. For dwarfs, our synthetic indices could well reproduce the behaviors of the observational indices versus stellar parameters, which verifies the validity of our index definitions for dwarfs. For giants, the consistency between our synthetic indices and the observational

  4. Ca II Triplet Spectroscopy of Small Magellanic Cloud Red Giants. III. Abundances and Velocities for a Sample of 14 Clusters

    CERN Document Server

    Parisi, M C; Clariá, J J; Villanova, S; Marcionni, N; Sarajedini, A; Grocholski, A J

    2015-01-01

    We obtained spectra of red giants in 15 Small Magellanic Cloud (SMC) clusters in the region of the CaII lines with FORS2 on the Very Large Telescope (VLT). We determined the mean metallicity and radial velocity with mean errors of 0.05 dex and 2.6 km/s, respectively, from a mean of 6.5 members per cluster. One cluster (B113) was too young for a reliable metallicity determination and was excluded from the sample. We combined the sample studied here with 15 clusters previously studied by us using the same technique, and with 7 clusters whose metallicities determined by other authors are on a scale similar to ours. This compilation of 36 clusters is the largest SMC cluster sample currently available with accurate and homogeneously determined metallicities. We found a high probability that the metallicity distribution is bimodal, with potential peaks at -1.1 and -0.8 dex. Our data show no strong evidence of a metallicity gradient in the SMC clusters, somewhat at odds with recent evidence from CaT spectra of a lar...

  5. Ca II Triplet Spectroscopy of Small Magellanic Cloud Red Giants. IV. Abundances for a Large Sample of Field Stars and Comparison with the Cluster Sample

    Science.gov (United States)

    Parisi, M. C.; Geisler, D.; Carraro, G.; Clariá, J. J.; Villanova, S.; Gramajo, L. V.; Sarajedini, A.; Grocholski, A. J.

    2016-09-01

    This paper represents a major step forward in the systematic and homogeneous study of Small Magellanic Cloud (SMC) star clusters and field stars carried out by applying the calcium triplet technique. We present in this work the radial velocity and metallicity of approximately 400 red giant stars in 15 SMC fields, with typical errors of about 7 km s‑1 and 0.16 dex, respectively. We added to this information our previously determined metallicity values for 29 clusters and approximately 350 field stars using the identical techniques. Using this enlarged sample, we analyze the metallicity distribution and gradient in this galaxy. We also compare the chemical properties of the clusters and of their surrounding fields. We find a number of surprising results. While the clusters, taken as a whole, show no strong evidence for a metallicity gradient (MG), the field stars exhibit a clear negative gradient in the inner region of the SMC, consistent with the recent results of Dobbie et al. For distances to the center of the galaxy less than 4°, field stars show a considerably smaller metallicity dispersion than that of the clusters. However, in the external SMC regions, clusters and field stars exhibit similar metallicity dispersions. Moreover, in the inner region of the SMC, clusters appear to be concentrated in two groups: one more metal-poor and another more metal-rich than field stars. Individually considered, neither cluster group presents an MG. Most surprisingly, the MG for both stellar populations (clusters and field stars) appears to reverse sign in the outer regions of the SMC. The difference between the cluster metallicity and the mean metallicity of the surrounding field stars turns out to be a strong function of the cluster metallicity. These results could be indicating different chemical evolution histories for these two SMC stellar populations. They could also indicate variations in the chemical behavior of the SMC in its internal and external regions.

  6. OI and CaII observations in intermediate redshift quasars

    CERN Document Server

    Martínez-Aldama, Mary Loli; Marziani, Paola; Sulentic, Jack W; Bressan, Alessandro; Chen, Yang; Stirpe, Giovanna M

    2015-01-01

    We present an unprecedented spectroscopic survey of the CaII triplet + OI for a sample of 14 luminous ($-$26 $\\gtrsim$ M$_V$ $\\gtrsim$ $-$29), intermediate redshift (0.85 $\\lesssim$ $z$ $\\lesssim$ 1.65) quasars. The ISAAC spectrometer at ESO VLT allowed us to cover the CaII NIR spectral region redshifted into the H and K windows. We describe in detail our data analysis which enabled us to detect CaII triplet emission in all 14 sources (with the possible exception of HE0048-2804) and to retrieve accurate line widths and fluxes of the triplet and OI $\\lambda$8446. The new measurements show trends consistent with previous lower $z$ observations, indicating that CaII and optical FeII emission are probably closely related. The ratio between the CaII triplet and the optical FeII blend at $\\lambda$4570 $\\AA$ is apparently systematically larger in our intermediate redshift sample relative to a low-$z$ control sample. Even if this result needs a larger sample for adequate interpretation, higher CaII/optical FeII shoul...

  7. Carotenoid triplet states in photosystem II: coupling with low-energy states of the core complex.

    Science.gov (United States)

    Santabarbara, Stefano; Agostini, Alessandro; Casazza, Anna Paola; Zucchelli, Giuseppe; Carbonera, Donatella

    2015-02-01

    The photo-excited triplet states of carotenoids, sensitised by triplet-triplet energy transfer from the chlorophyll triplet states, have been investigated in the isolated Photosystem II (PSII) core complex and PSII-LHCII (Light Harvesting Complex II) supercomplex by Optically Detected Magnetic Resonance techniques, using both fluorescence (FDMR) and absorption (ADMR) detection. The absence of Photosystem I allows us to reach the full assignment of the carotenoid triplet states populated in PSII under steady state illumination at low temperature. Five carotenoid triplet ((3)Car) populations were identified in PSII-LHCII, and four in the PSII core complex. Thus, four (3)Car populations are attributed to β-carotene molecules bound to the core complex. All of them show associated fluorescence emission maxima which are relatively red-shifted with respect to the bulk emission of both the PSII-LHCII and the isolated core complexes. In particular the two populations characterised by Zero Field Splitting parameters |D|=0.0370-0.0373 cm(-1)/|E|=0.00373-0.00375 cm(-1) and |D|=0.0381-0.0385 cm(-1)/|E|=0.00393-0.00389 cm(-1), are coupled by singlet energy transfer with chlorophylls which have a red-shifted emission peaking at 705 nm. This observation supports previous suggestions that pointed towards the presence of long-wavelength chlorophyll spectral forms in the PSII core complex. The fifth (3)Car component is observed only in the PSII-LHCII supercomplex and is then assigned to the peripheral light harvesting system. PMID:25481107

  8. He II Heat Exchanger Test Unit for the LHC Inner Triplet

    CERN Document Server

    Blanco-Viñuela, E; Huang, Y; Nicol, T H; Peterson, T; Van Weelderen, R

    2002-01-01

    The Inner Triplet Heat Exchanger Test Unit (IT-HXTU) is a 30-m long thermal model designed at Fermilab, built in US industry, fully automated and tested at CERN as part of the US LHC program to develop the LHC Interaction Region quadrupole system. The cooling scheme of the IT-HXTU is based on heat exchange between stagnant pressurized He II in the magnet cold mass and saturated He II (two-phase) flowing in a heat exchanger located outside of and parallel to the cold mass. The purposes of this test are, among others, to validate the proposed cooling scheme and to define an optimal control strategy to be implemented in the future LHC accelerator. This paper discusses the results for the heat exchanger test runs and emphasizes the thermal and hydraulic behavior of He II for the inner triplet cooling scheme.

  9. The Integrated Calcium II Triplet as a Metallicity Indicator: Comparisons with High Resolution [Fe/H] in M31 Globular Clusters

    CERN Document Server

    Sakari, Charli M

    2015-01-01

    Medium resolution (R=4,000 to 9,000) spectra of the near infrared Ca II lines (at 8498, 8542, and 8662 A) in M31 globular cluster integrated light spectra are presented. In individual stars the Ca II triplet (CaT) traces stellar metallicity; this paper compares integrated CaT strengths to well determined, high precision [Fe/H] values from high resolution integrated light spectra. The target globular clusters cover a wide range in metallicity (from [Fe/H] = -2.1 to -0.2). While most are older than 10 Gyr, some may be of intermediate age (2-6 Gyr). A handful (3-6) have detailed abundances (e.g. low [Ca/Fe]) that indicate they may have been accreted from dwarf galaxies. Using various measurements and definitions of CaT strength, it is confirmed that for GCs with [Fe/H] < -0.4 and older than 2 Gyr the integrated CaT traces cluster [Fe/H] to within about 0.2 dex, independent of age. CaT lines in metal rich GCs are very sensitive to nearby atomic lines (and TiO molecular lines in the most metal rich GCs), largel...

  10. Nonlinear Color--Metallicity Relations of Globular Clusters. VI. On Calcium II Triplet Based Metallicities of Globular Clusters in Early-type Galaxies

    CERN Document Server

    Chung, Chul; Lee, Sang-Yoon; Lee, Young-Wook

    2016-01-01

    The metallicity distribution function of globular clusters (GCs) in galaxies is a key to understanding galactic formation and evolution. The calcium II triplet (CaT) index has recently become a popular metal abundance indicator thanks to its sensitivity to GC metallicity. Here we revisit and assess the reliability of CaT as a metallicity indicator using our new stellar population synthesis simulations based on empirical, high-resolution fluxes. The model shows that the CaT strength of old ($>$ 10 Gyr) GCs is proportional to ${\\rm [Fe/H]}$ below $-0.5$. In the modest metal-rich regime, however, CaT does not increase anymore with ${\\rm [Fe/H]}$ due to the little contribution from coolest red giant stars to the CaT absorption. The nonlinear nature of the color--$CaT$ relation is confirmed by the observations of GCs in nearby early-type galaxies. This indicates that the CaT should be used carefully when deriving metallicities of metal-rich stellar populations. Our results offer an explanation for the observed sha...

  11. Low ionization lines in high luminosity quasars: The calcium triplet

    OpenAIRE

    Martínez-Aldama, Mary Loli; Dultzin, Deborah; Marziani, Paola; Sulentic, Jack W.; Chen, Yang; Bressan, Alessandro; Stirpe, Giovanna M.

    2013-01-01

    In order to investigate where and how low ionization lines are emitted in quasars we are studying a new collection of spectra of the CaII triplet at $\\lambda$8498, $\\lambda$8542, $\\lambda$8662 observed with the Very Large Telescope (VLT) using the Infrared Spectrometer And Array Camera (ISAAC). Our sample involves luminous quasars at intermediate redshift for which CaII observations are almost nonexistent. We fit the CaII triplet and the OI $\\lambda$8446 line using the H$\\beta$ profile as a m...

  12. Low ionization lines in high luminosity quasars: The calcium triplet

    CERN Document Server

    Martínez-Aldama, Mary Loli; Marziani, Paola; Sulentic, Jack W; Chen, Yang; Bressan, Alessandro; Stirpe, Giovanna M

    2013-01-01

    In order to investigate where and how low ionization lines are emitted in quasars we are studying a new collection of spectra of the CaII triplet at $\\lambda$8498, $\\lambda$8542, $\\lambda$8662 observed with the Very Large Telescope (VLT) using the Infrared Spectrometer And Array Camera (ISAAC). Our sample involves luminous quasars at intermediate redshift for which CaII observations are almost nonexistent. We fit the CaII triplet and the OI $\\lambda$8446 line using the H$\\beta$ profile as a model. We derive constraints on the line emitting region from the relative strength of the CaII triplet, OI $\\lambda$8446 and H$\\beta$.

  13. A fluorescence detected magnetic resonance investigation of the carotenoid triplet states associated with Photosystem II of isolated spinach thylakoid membranes

    CERN Document Server

    Santabarbara, S; Carbonera, D; Heathcote, P

    2005-01-01

    The carotenoid triplet populations associated with the fluorescence emission chlorophyll forms of Photosystem II have been investigated in isolated spinach thylakoid membranes by means of fluorescence detected magnetic resonance in zero field (FDMR). The spectra collected in the 680-690 nm emission range, have been fitted by a global analysis procedure. At least five different carotenoid triplet states coupled to the terminal emitting chlorophyll forms of PS II, peaking at 682 nm, 687 nm and 692 nm, have been characterised. The triplets associated with the outer antenna emission forms, at 682 nm, have zero field splitting parameters D = 0.0385 cm/sup -1/, E = 0.00367 cm/sup -1/; D = 0.0404 cm/sup -1/, E = 0.00379 cm/sup -1/ and D = 0.0386 cm/sup -1/, E = 0.00406 cm/sup -1/ which are very similar to those previously reported for the xanthophylls of the isolated LHC II complex. Therefore the FDMR spectra recorded in this work provide insights into the organisation of the LHC II complex in the unperturbed enviro...

  14. Spectropolarimetric observations of the Ca II 8498 A and 8542 A lines in the quiet Sun

    OpenAIRE

    Pietarila, A.; Socas-Navarro, H.; Bogdan, T.

    2007-01-01

    The Ca II infrared triplet is one of the few magnetically sensitive chromospheric lines available for ground-based observations. We present spectropolarimetric observations of the 8498 A and 8542 A lines in a quiet Sun region near a decaying active region and compare the results with a simulation of the lines in a high plasma-beta regime. Cluster analysis of Stokes V profile pairs shows that the two lines, despite arguably being formed fairly close, often do not have similar shapes. In the ne...

  15. Ca II Absorbers in the Sloan Digital Sky Survey: Statistics

    CERN Document Server

    Sardane, Gendith M; Rao, Sandhya M

    2014-01-01

    We present the results of a survey for CaII 3934,3969 absorption-line systems culled from ~ 95,000 Sloan Digital Sky Survey (SDSS) Data Release 7 and Data Release 9 quasar spectra. With 435 doublets identified in the catalog, this list is the largest CaII catalog compiled to date, spanning redshifts z = 0.3 A, is n_0=0.017 +/- 0.001. In comparison to MgII surveys, we found that only 3% of MgII systems in the SDSS have CaII, confirming that it is rare to identify CaII in quasar absorption-line surveys. We also report on some preliminary investigations of the nature of the two populations of CaII absorbers, and show that they can likely be distinguished using their MgII properties.

  16. FAST INVERSION OF SOLAR Ca II SPECTRA

    Energy Technology Data Exchange (ETDEWEB)

    Beck, C. [National Solar Observatory (NSO), 3010 Coronal Loop, Sunspot, NM 88349 (United States); Choudhary, D. P. [Department of Physics and Astronomy, California State University, Northridge (CSUN), CA 91330-8268 (United States); Rezaei, R. [Kiepenheuer-Institut für Sonnenphysik (KIS), Schöneckstr. 6, D-79104 Freiburg (Germany); Louis, R. E., E-mail: cbeck@nso.edu [Leibniz-Institut für Astrophysik (AIP), An der Sternwarte 16, D-14482 Potsdam (Germany)

    2015-01-10

    We present a fast (<<1 s per profile) inversion code for solar Ca II lines. The code uses an archive of spectra that are synthesized prior to the inversion under the assumption of local thermodynamic equilibrium (LTE). We show that it can be successfully applied to spectrograph data or more sparsely sampled spectra from two-dimensional spectrometers. From a comparison to a non-LTE inversion of the same set of spectra, we derive a first-order non-LTE correction to the temperature stratifications derived in the LTE approach. The correction factor is close to unity up to log τ ∼ –3 and increases to values of 2.5 and 4 at log τ = –6 in the quiet Sun and the umbra, respectively.

  17. Tuning the Reactivity of Radical through a Triplet Diradical Cu(II) Intermediate in Radical Oxidative Cross-Coupling

    Science.gov (United States)

    Zhou, Liangliang; Yi, Hong; Zhu, Lei; Qi, Xiaotian; Jiang, Hanpeng; Liu, Chao; Feng, Yuqi; Lan, Yu; Lei, Aiwen

    2015-11-01

    Highly selective radical/radical cross-coupling is paid more attention in bond formations. However, due to their intrinsic active properties, radical species are apt to achieve homo-coupling instead of cross-coupling, which makes the selective cross-coupling as a great challenge and almost untouched. Herein a notable strategy to accomplish direct radical/radical oxidative cross-coupling has been demonstrated, that is metal tuning a transient radical to a persistent radical intermediate followed by coupling with another transient radical. Here, a transient nitrogen-centered radical is tuned to a persistent radical complex by copper catalyst, followed by coupling with a transient allylic carbon-centered radical. Firstly, nitrogen-centered radical generated from N-methoxybenzamide stabilized by copper catalyst was successfully observed by EPR. Then DFT calculations revealed that a triplet diradical Cu(II) complex formed from the chelation N-methoxybenzamide nitrogen-centered radical to Cu(II) is a persistent radical species. Moreover, conceivable nitrogen-centered radical Cu(II) complex was observed by high-resolution electrospray ionization mass spectrometry (ESI-MS). Ultimately, various allylic amides derivatives were obtained in good yields by adopting this strategy, which might inspire a novel and promising landscape in radical chemistry.

  18. The resonance triplet at E_alpha = 4.5 MeV in the 40Ca(alpha,gamma)44Ti reaction

    CERN Document Server

    Schmidt, Konrad; Anders, Michael; Bemmerer, Daniel; Boretzky, Konstanze; Caciolli, Antonio; Degering, Detlev; Dietz, Mirco; Dressler, Rugard; Elekes, Zoltán; Fülöp, Zsolt; Gyürky, György; Hannaske, Roland; Junghans, Arnd R; Marta, Michele; Menzel, Marie-Luise; Munnik, Frans; Schumann, Dorothea; Schwengner, Ronald; Szücs, Tamás; Wagner, Andreas; Yakorev, Dmitry; Zuber, Kai

    2013-01-01

    The 40Ca(alpha,gamma)44Ti reaction is believed to be the main production channel for the radioactive nuclide 44Ti in core-collapse supernovae. Radiation from decaying 44Ti has been observed so far for two supernova remnants, and a precise knowledge of the 44Ti production rate may help improve supernova models. The 40Ca(alpha,gamma)44Ti astrophysical reaction rate is determined by a number of narrow resonances. Here, the resonance triplet at E_alpha = 4497, 4510, and 4523 keV is studied both by activation, using an underground laboratory for the gamma counting, and by in-beam gamma spectrometry. The target properties are determined by elastic recoil detection analysis and by nuclear reactions. The strengths of the three resonances are determined to omega gamma = (0.92+-0.20), (6.2+-0.5), and (1.32+-0.24) eV, respectively, a factor of two more precise than before. The strengths of this resonance triplet may be used in future works as a point of reference. In addition, the present new data directly affect the as...

  19. Ca II absorbers in the Sloan Digital Sky Survey: statistics

    Science.gov (United States)

    Sardane, Gendith M.; Turnshek, David A.; Rao, Sandhya M.

    2014-10-01

    We present the results of a survey for Ca II λλ3934, 3969 absorption-line systems culled from ˜95 000 Sloan Digital Sky Survey (SDSS) Data Release 7 and Data Release 9 quasar spectra. With 435 doublets identified in the catalogue, this list is the largest Ca II catalogue compiled to date, spanning redshifts z history of the Universe. We derive statistics on the Ca II rest equivalent width distribution and incidence. We find that the λ3934 rest equivalent width (W0^{λ 3934}) distribution cannot be described by a single exponential function. A double exponential function is required to produce a satisfactory description. The function can be written as a sum of weak and strong components: {partial n}/{partial W0^{λ 3934}}= ({N_{wk}^{ast }}/{W_{wk}^{ast }}) exp ({ -{W0^{λ 3934}}/{W_{wk}^{ast } } }) + ({N_{str}^{ast }}/{W_{str}^{ast }}) exp ({ -{W0^{λ 3934}}/{W_{str}^{ast } } }). A maximum likelihood fit to the unbinned data indicates N_{wk}^{ast }=0.140± 0.029, W_{wk}^{ast }=0.165± 0.020 \\unicode{197}, N_{str}^{ast }=0.024± 0.020, and W_{str}^{ast }=0.427± 0.101 Å. This suggests that the Ca II absorbers are composed of at least two distinct populations. The incidence of the overall Ca II absorber population does not show evidence for evolution in the standard cosmology. The normalization of the no-evolution curve, i.e. the value of the Ca II incidence extrapolated to redshift z = 0, for W0^{λ 3934} ≥ 0.3 Å, is n0 = 0.017 ± 0.001. In comparison to Mg II surveys, we found that only 3 per cent of Mg II systems in the SDSS have Ca II, confirming that Ca II systems are rare. We also report on some preliminary investigations of the nature of the two populations of Ca II absorbers, and show that they can likely be distinguished using their Mg II properties.

  20. CaII Κ Imaging to Understand UV Irradiance Variability

    Indian Academy of Sciences (India)

    R. Kariyappa

    2000-09-01

    To identify and understand the underlying physical mechanisms of total solar and UV irradiance variability and to estimate the contribution of various chromospheric features to UV irradiance, detailed analysis of spatially resolved data is required. The various chromospheric features have been segregated and different parameters have been derived from CaII Κ Spectroheliograms of NSO/Sac Peak and Kodaikanal Observatory and compared with UV irradiance flux measured in MgII h and k lines by NOAA 9 satellite. The important results of this detailed analysis of CaII Κ Images of 1992 together with UV irradiance data will be discussed in this paper.

  1. Spectropolarimetric observations of the Ca II 8498 A and 8542 A lines in the quiet Sun

    CERN Document Server

    Pietarila, A; Bogdan, T

    2007-01-01

    The Ca II infrared triplet is one of the few magnetically sensitive chromospheric lines available for ground-based observations. We present spectropolarimetric observations of the 8498 A and 8542 A lines in a quiet Sun region near a decaying active region and compare the results with a simulation of the lines in a high plasma-beta regime. Cluster analysis of Stokes V profile pairs shows that the two lines, despite arguably being formed fairly close, often do not have similar shapes. In the network, the local magnetic topology is more important in determining the shapes of the Stokes V profiles than the phase of the wave, contrary to what our simulations show. We also find that Stokes V asymmetries are very common in the network, and the histograms of the observed amplitude and area asymmetries differ significantly from the simulation. Both the network and internetwork show oscillatory behavior in the Ca II lines. It is stronger in the network, where shocking waves, similar to those in the high-beta simulation...

  2. Correlation Between Sunspot Number and ca II K Emission Index

    CERN Document Server

    Bertello, Luca; Tlatov, Andrey; Singh, Jagdev

    2016-01-01

    Long-term synoptic observations in the resonance line of Ca II K constitute a fundamental database for a variety of retrospective analyses of the state of the solar magnetism. Synoptic Ca II K observations began in late 1904 at the Kodaikanal Observatory, in India. In early 1970s, the National Solar Observatory (NSO) at Sacramento Peak (USA) started a new program of daily Sun-as-a-star observations in the Ca II K line. Today the NSO is continuing these observations through its Synoptic Optical Long-term Investigations of the Sun (SOLIS) facility. These different data sets can be combined into a single disk-integrated Ca II K index time series that describes the average properties of the chromospheric emission over several solar cycles. We present such a Ca II K composite and discuss its correlation with the new entirely revised sunspot number data series. For this preliminary investigation, the scaling factor between pairs of time series was determined assuming a simple linear model for the relationship betwe...

  3. Spectropolarimetric capabilities of Ca II 8542 Å line

    Science.gov (United States)

    Quintero Noda, C.; Shimizu, T.; de la Cruz Rodríguez, J.; Katsukawa, Y.; Ichimoto, K.; Anan, T.; Suematsu, Y.

    2016-07-01

    The next generation of space- and ground-based solar missions aim to study the magnetic properties of the solar chromosphere using the infrared Ca II lines and the He I 10830 Å line. The former seem to be the best candidates to study the stratification of magnetic fields in the solar chromosphere and their relation to the other thermodynamical properties underlying the chromospheric plasma. The purpose of this work is to provide a detailed analysis of the diagnostic capabilities of the Ca II 8542 Å line, anticipating forthcoming observational facilities. We study the sensitivity of the Ca II 8542 Å line to perturbations applied to the physical parameters of reference semi-empirical 1D model atmospheres using response functions and we make use of 3D magnetohydrodynamics simulations to examine the expected polarization signals for moderate magnetic field strengths. Our results indicate that the Ca II 8542 Å line is mostly sensitive to the layers enclosed in the range log τ = [0, -5.5], under the physical conditions that are present in our model atmospheres. In addition, the simulated magnetic flux tube generates strong longitudinal signals in its centre and moderate transversal signals, due to the vertical expansion of magnetic field lines, in its edge. Thus, observing the Ca II 8542 Å line we will be able to infer the 3D geometry of moderate magnetic field regions.

  4. Improvements in the determination of ISS Ca II K parameters

    CERN Document Server

    Bertello, Luca; Harvey, Jack W; Toussaint, Roberta M

    2011-01-01

    Measurements of the ionized Ca II K line are one of the major resources for long-term studies of solar and stellar activity. They also play a critical role in many studies related to solar irradiance variability, particularly as a ground-based proxy to model the solar ultraviolet flux variation that may influence the Earth's climate. Full disk images of the Sun in Ca II K have been available from various observatories for more than 100 years and latter synoptic Sun-as-a-star observations in Ca II K began in the early 1970s. One of these instruments, the Integrated Sunlight Spectrometer (ISS) has been in operation at Kitt Peak (Arizona) since late 2006. The ISS takes daily observations of solar spectra in nine spectra bands, including the Ca II K and H line s. We describe recent improvements in data reduction of Ca II K observations, and present time variations of nine parameters derived from the profile of this spectral line.

  5. Spectropolarimetric capabilities of Ca II 8542 A line

    CERN Document Server

    Noda, C Quintero; Rodríguez, J de la Cruz; Katsukawa, Y; Ichimoto, K; Anan, T; Suematsu, Y

    2016-01-01

    The next generation of space and ground-based solar missions aim to study the magnetic properties of the solar chromosphere using the infrared Ca II lines and the He I 10830 {\\AA} line. The former seem to be the best candidates to study the stratification of magnetic fields in the solar chromosphere and their relation to the other thermodynamical properties underlying the chromospheric plasma. The purpose of this work is to provide a detailed analysis of the diagnostic capabilities of the Ca II 8542 {\\AA} line, anticipating forthcoming observational facilities. We study the sensitivity of the Ca II 8542 {\\AA} line to perturbations applied to the physical parameters of reference semi-empirical 1D model atmospheres using response functions and we make use of 3D MHD simulations to examine the expected polarization signals for moderate magnetic field strengths. Our results indicate that the Ca II 8542 {\\AA} line is mostly sensitive to the layers enclosed between $\\log$ $\\tau=[0,-5.5]$, under the physical conditio...

  6. Study on Effect of Gd (III) Speciation on Ca (II) Speciation in Human Blood Plasma by Computer Simulation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Ca (II) speciation and effect of Gd (III) speciation on Ca (II) speciation in human blood plasma were studied by computer simulation. [CaHCO3]+ is a predominant compound species of Ca (II). Gd (III) can compete with Ca (II) for biological molecules. The presence of Gd (III) results in a increase of concentration of free Ca (II) and a decrease of concentration of Ca (II) compounds.

  7. Novel Roles for Peroxynitrite in Angiotensin II and CaMKII Signaling

    OpenAIRE

    Chaoming Zhou; Ramaswamy, Swarna S.; Johnson, Derrick E.; Vitturi, Dario A.; Schopfer, Franciso J.; Freeman, Bruce A.; Andy Hudmon; Levitan, Edwin S.

    2016-01-01

    Ca2+/calmodulin-dependent protein kinase II (CaMKII) oxidation controls excitability and viability. While hydrogen peroxide (H2O2) affects Ca2+-activated CaMKII in vitro, Angiotensin II (Ang II)-induced CaMKIIδ signaling in cardiomyocytes is Ca2+ independent and requires NADPH oxidase-derived superoxide, but not its dismutation product H2O2. To better define the biological regulation of CaMKII activation and signaling by Ang II, we evaluated the potential for peroxynitrite (ONOO−) to mediate ...

  8. The human carbonic anhydrase isoenzymes I and II (hCA I and II) inhibition effects of trimethoxyindane derivatives.

    Science.gov (United States)

    Taslimi, Parham; Gulcin, Ilhami; Ozgeris, Bunyamin; Goksu, Suleyman; Tumer, Ferhan; Alwasel, Saleh H; Supuran, Claudiu T

    2016-01-01

    Carbonic anhydrases (CAs, EC 4.2.1.1) had six genetically distinct families described to date in various organisms. There are 16 known CA isoforms in humans. Human CA isoenzymes I and II (hCA I and hCA II) are ubiquitous cytosolic isoforms. Acetylcholine esterase (AChE. EC 3.1.1.7) is a hydrolase that hydrolyzes the neurotransmitter acetylcholine relaying the signal from the nerve. In this study, some trimethoxyindane derivatives were investigated as inhibitors against the cytosolic hCA I and II isoenzymes, and AChE enzyme. Both hCA isozymes were inhibited by trimethoxyindane derivatives in the low nanomolar range. These compounds were good hCA I inhibitors (Kis in the range of 1.66-4.14 nM) and hCA II inhibitors (Kis of 1.37-3.12 nM) and perfect AChE inhibitors (Kis in the range of 1.87-7.53 nM) compared to acetazolamide as CA inhibitor (Ki: 6.76 nM for hCA I and Ki: 5.85 nM for hCA II) and Tacrine as AChE inhibitor (Ki: 7.64 nM). PMID:25697270

  9. Migration of Ca II H bright points in the internetwork

    Science.gov (United States)

    Jafarzadeh, S.; Cameron, R. H.; Solanki, S. K.; Pietarila, A.; Feller, A.; Lagg, A.; Gandorfer, A.

    2014-03-01

    Context. The migration of magnetic bright point-like features (MBP) in the lower solar atmosphere reflects the dispersal of magnetic flux as well as the horizontal flows of the atmospheric layer they are embedded in. Aims: We analyse trajectories of the proper motion of intrinsically magnetic, isolated internetwork Ca ii H MBPs (mean lifetime 461 ± 9 s) to obtain their diffusivity behaviour. Methods: We use seeing-free high spatial and temporal resolution image sequences of quiet-Sun, disc-centre observations obtained in the Ca ii H 3968 Å passband of the Sunrise Filter Imager (SuFI) onboard the Sunrise balloon-borne solar observatory. Small MBPs in the internetwork are automatically tracked. The trajectory of each MBP is then calculated and described by a diffusion index (γ) and a diffusion coefficient (D). We also explore the distribution of the diffusion indices with the help of a Monte Carlo simulation. Results: We find γ = 1.69 ± 0.08 and D = 257 ± 32 km2 s-1 averaged over all MBPs. Trajectories of most MBPs are classified as super-diffusive, i.e. γ > 1, with the determined γ being the largest obtained so far to our knowledge. A direct correlation between D and timescale (τ) determined from trajectories of all MBPs is also obtained. We discuss a simple scenario to explain the diffusivity of the observed, relatively short-lived MBPs while they migrate within a small area in a supergranule (i.e. an internetwork area). We show that the scatter in the γ values obtained for individual MBPs is due to their limited lifetimes. Conclusions: The super-diffusive MBPs can be described as random walkers (due to granular evolution and intergranular turbulence) superposed on a large systematic (background) velocity, caused by granular, mesogranular, and supergranular flows.

  10. Ca II H and K emission from late-type stars

    International Nuclear Information System (INIS)

    This thesis is based on a study of the Ca II H and K emission features of late main-sequence stars. In Chapter II it is shown that rotation periods can be determined from a modulation in the Ca II H and K signal for many stars in a broad range of spectral types. In Chapter III it is shown that a clear correlation exists between Ca II H and K emission and rotational velocity in active main-sequence stars. There is an indication for a (probably colour-dependent) critical velocity at which the Ca II H and K emission suddenly drops. Chapter IV discusses the dependence of Ca II H and K emission on the rotation rate for evolved stars. (Auth./C.F.)

  11. Comparison between Mg II k and Ca II H Images Recorded by SUNRISE/SuFI

    Science.gov (United States)

    Danilovic, S.; Hirzberger, J.; Riethmüller, T. L.; Solanki, S. K.; Barthol, P.; Berkefeld, T.; Gandorfer, A.; Gizon, L.; Knölker, M.; Schmidt, W.; Blanco Rodríguez, J.; Del Toro Iniesta, J. C.

    2014-03-01

    We present a comparison of high-resolution images of the solar surface taken in the Mg II k and Ca II H channels of the Filter Imager on the balloon-borne solar observatory SUNRISE. The Mg and Ca lines are sampled with 0.48 nm and 0.11 nm wide filters, respectively. The two channels show remarkable qualitative and quantitative similarities in the quiet Sun, in an active region plage and during a small flare. However, the Mg filtergrams display 1.4-1.7 times higher intensity contrast and appear more smeared and smoothed in the quiet Sun. In addition, the fibrils in a plage are wider. Although the exposure time is 100 times longer for Mg images, the evidence suggests that these differences cannot be explained only with instrumental effects or the evolution of the solar scene. The differences at least partially arise because of different line-formation heights, the stronger response of Mg k emission peaks to the higher temperatures, and the larger height range sampled by the broad Mg filter used here. This is evidently manifested during the flare when a surge in Mg evolves differently than in Ca.

  12. Comparison between Mg II k and Ca II H images recorded by SUNRISE/SuFI

    Energy Technology Data Exchange (ETDEWEB)

    Danilovic, S.; Hirzberger, J.; Riethmüller, T. L.; Solanki, S. K.; Barthol, P.; Gandorfer, A.; Gizon, L. [Max-Planck-Institut für Sonnensystemforschung, Max-Planck-Str. 2, D-37191 Katlenburg-Lindau (Germany); Berkefeld, T.; Schmidt, W. [Kiepenheuer-Institut für Sonnenphysik, Schöneckstr. 6, D-79104 Freiburg (Germany); Knölker, M. [High Altitude Observatory, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307-3000 (United States); Rodríguez, J. Blanco [Image Processing Laboratory, University of Valencia, P.O. Box 22085, E-46980 Paterna, Valencia (Spain); Iniesta, J. C. Del Toro, E-mail: danilovic@mps.mpg.de [Instituto de Astrofísica de Andalucía (CSIC), Apartado de Correos 3004, E-18080 Granada (Spain)

    2014-03-20

    We present a comparison of high-resolution images of the solar surface taken in the Mg II k and Ca II H channels of the Filter Imager on the balloon-borne solar observatory SUNRISE. The Mg and Ca lines are sampled with 0.48 nm and 0.11 nm wide filters, respectively. The two channels show remarkable qualitative and quantitative similarities in the quiet Sun, in an active region plage and during a small flare. However, the Mg filtergrams display 1.4-1.7 times higher intensity contrast and appear more smeared and smoothed in the quiet Sun. In addition, the fibrils in a plage are wider. Although the exposure time is 100 times longer for Mg images, the evidence suggests that these differences cannot be explained only with instrumental effects or the evolution of the solar scene. The differences at least partially arise because of different line-formation heights, the stronger response of Mg k emission peaks to the higher temperatures, and the larger height range sampled by the broad Mg filter used here. This is evidently manifested during the flare when a surge in Mg evolves differently than in Ca.

  13. Comparison between Mg II k and Ca II H images recorded by SUNRISE/SuFI

    International Nuclear Information System (INIS)

    We present a comparison of high-resolution images of the solar surface taken in the Mg II k and Ca II H channels of the Filter Imager on the balloon-borne solar observatory SUNRISE. The Mg and Ca lines are sampled with 0.48 nm and 0.11 nm wide filters, respectively. The two channels show remarkable qualitative and quantitative similarities in the quiet Sun, in an active region plage and during a small flare. However, the Mg filtergrams display 1.4-1.7 times higher intensity contrast and appear more smeared and smoothed in the quiet Sun. In addition, the fibrils in a plage are wider. Although the exposure time is 100 times longer for Mg images, the evidence suggests that these differences cannot be explained only with instrumental effects or the evolution of the solar scene. The differences at least partially arise because of different line-formation heights, the stronger response of Mg k emission peaks to the higher temperatures, and the larger height range sampled by the broad Mg filter used here. This is evidently manifested during the flare when a surge in Mg evolves differently than in Ca.

  14. Dissociation of Ca sup 2+ entry and Ca sup 2+ mobilization responses to angiotensin II in bovine adrenal chromaffin cells

    Energy Technology Data Exchange (ETDEWEB)

    Stauderman, K.A.; Pruss, R.M. (Merrell Dow Research Institute, Cincinnati, OH (USA))

    1989-11-05

    In fura-2-loaded bovine adrenal chromaffin cells, 0.5 microM angiotensin II (AII) stimulated a 185 +/- 19 nM increase of intracellular-free calcium (( Ca2+)i) approximately 3 s after addition. The time from the onset of the response until achieving 50% recovery (t 1/2) was 67 +/- 10 s. Concomitantly, AII stimulated both the release of 45Ca2+ from prelabeled cells, and a 4-5-fold increase of (3H)inositol 1,4,5-trisphosphate (( 3H)Ins(1,4,5)P3) levels. In the presence of 50 microM LaCl3, or when extracellular-free Ca2+ (( Ca2+)o) was less than 100 nM, AII still rapidly increased (Ca2+)i by 95-135 nM, but the t 1/2 for recovery was then only 23-27 s. In medium with 1 mM MnCl2 present, AII also stimulated a small amount of Mn2+ influx, as judged by quenching of the fura-2 signal. When (Ca2+)o was normal (1.1 mM) or low (less than 60 nM), 1-2 microM ionomycin caused (Ca2+)i to increase 204 +/- 26 nM, while also releasing 45-55% of bound 45Ca2+. With low (Ca2+)o, ionomycin pretreatment abolished both the (Ca2+)i increase and 45Ca2+ release stimulated by AII. However, after ionomycin pretreatment in normal medium, AII produced a La3+-inhibitable increase of (Ca2+)i (103 +/- 13 nM) with a t 1/2 of 89 +/- 8 s, but no 45Ca2+ release. No pretreatment condition altered AII-induced formation of (3H)Ins(1,4,5)P3. We conclude that AII increased (Ca2+)i via rapid and transient Ca2+ mobilization from Ins(1,4,5)P3- and ionomycin-sensitive stores, accompanied (and/or followed) by Ca2+ entry through a La3+-inhibitable divalent cation pathway. Furthermore, the ability of AII to activate Ca2+ entry in the absence of Ca2+ mobilization (i.e. after ionomycin pretreatment) suggests a receptor-linked stimulus other than Ca2+ mobilization initiates Ca2+ entry.

  15. The Chemical Abundances of the Stellar Populations in the Leo I and Leo II dSph Galaxies

    OpenAIRE

    Bosler, Tammy L.; Smecker-Hane, Tammy A.; Stetson, Peter B

    2006-01-01

    We have obtained spectra of 102 red giant branch (RGB) stars in the Leo I dwarf spheroidal galaxy (dSph) and 74 RGB stars in the Leo II dSph using LRIS on the Keck I 10-meter Telescope. We report on the calcium abundances [Ca/H] derived from the strengths of the Ca II triplet absorption lines at 8498, 8542, 8662 angstroms in the stellar spectra using a new Ca II triplet calibration to [Ca/H]. The two galaxies have different average [Ca/H] values of -1.34 +/- 0.02 for Leo I and -1.65 +/- 0.02 ...

  16. Structure-function of the multifunctional Ca2+/calmodulin-dependent protein kinase II.

    Science.gov (United States)

    Hudmon, Andy; Schulman, Howard

    2002-06-15

    Ca2+/calmodulin (CaM)-dependent protein kinase (CaMKII) is a ubiquitous mediator of Ca2+-linked signalling that phosphorylates a wide range of substrates to co-ordinate and regulate Ca2+-mediated alterations in cellular function. The transmission of information by the kinase from extracellular stimuli and the intracellular Ca2+ rise is not passive. Rather, its multimeric structure and autoregulation enable this enzyme to participate actively in the sensitivity, timing and location of its action. CaMKII can: (i) be activated in a Ca2+-spike frequency-dependent manner; (ii) become independent of its initial Ca2+/CaM activators; and (iii) undergo a 'molecular switch-like' behaviour, which is crucial for certain forms of learning and memory. CaMKII is derived from a family of four homologous but distinct genes, with over 30 alternatively spliced isoforms described at present. These isoforms possess diverse developmental and anatomical expression patterns, as well as subcellular localization. Six independent catalytic/autoregulatory domains are connected by a narrow stalk-like appendage to each hexameric ring within the dodecameric structure. Ca2+/CaM binding activates the enzyme by disinhibiting the autoregulatory domain; this process initiates an intra-holoenzyme autophosphorylation reaction that induces complex changes in the enzyme's sensitivity to Ca2+/CaM, including the generation of Ca2+/CaM-independent (autonomous) activity and marked increase in affinity for CaM. The role of CaMKII in Ca2+ signal transduction is shaped by its autoregulation, isoenzymic type and subcellular localization. The molecular determinants and mechanisms producing these processes are discussed as they relate to the structure-function of this multifunctional protein kinase. PMID:11931644

  17. K-band Imaging of strong CaII-absorber host galaxies at z~1

    CERN Document Server

    Hewett, Paul

    2007-01-01

    We present K-band imaging of fields around 30 strong CaII absorption line systems, at 0.7CaII absorption of the form (L/L*)^0.7 reproduces the observations well. The luminosity-dependent cross-section for the CaII absorbers appears to be significantly stronger than the established (L/L*)^0.4 dependence for MgII absorbers. The associated galaxies lie at large physical distances from the CaII-absorbing gas; we find a mean impact parameter of 24kpc (H0=70km\\s\\Mpc). Combined with the observed number density of CaII absorbers the large physical separations result in an inferred filling factor of only ~10 per cent. The physical origin of the strong CaII absorption remains unclear,...

  18. Identification of the site on calcineurin phosphorylated by Ca+/CaM-dependent kinase II: Modification of the CaM-binding domain

    International Nuclear Information System (INIS)

    The catalytic subunit of the Ca2+/calmodulin- (CaM) dependent phosphoprotein phosphatase calcineurin (CN) was phosphorylated by an activated form of Ca2+/CaM-dependent protein kinase II (CaM-kinase II) incorporating approximately 1 mol of phosphoryl group/mol of catalytic subunit, in agreement with a value previously reported. Cyanogen bromide cleavage of radiolabeled CN followed by peptide fractionation using reverse-phase high-performance liquid chromatography yielded a single labeled peptide that contained a phosphoserine residue. Microsequencing of the peptide allowed both the determination of the cleavage cycle that released [32P]phosphoserine and the identity of amino acids adjacent to it. Comparison of this sequence with the sequences of methionyl peptides deduced from the cDNA structure of CN allowed the phosphorylated serine to be uniquely identified. Interestingly, the phosphoserine exists in the sequence Met-Ala-Arg-Val-Phe-Ser(P)-Val-Leu-Arg-Glu, part of which lies within the putative CaM-binding sites. The phosphorylated serine residue was resistant to autocatalytic dephosphorylation, yet the slow rate of hydrolysis could be powerfully stimulated by effectors of CN phosphatase activity. The mechanism of dephosphorylation may be intramolecular since the initial rate was the same at phosphoCN concentrations of 2.5-250 nM

  19. Identification of the site on calcineurin phosphorylated by Ca sup + /CaM-dependent kinase II: Modification of the CaM-binding domain

    Energy Technology Data Exchange (ETDEWEB)

    Martensen, T.M.; Kincaid, R.L. (National Institute on Alcohol Abuse and Alcoholism, Rockville, MD (USA)); Martin, B.M. (National Institute of Mental Health, Bethesda, MD (USA))

    1989-11-28

    The catalytic subunit of the Ca{sup 2+}/calmodulin- (CaM) dependent phosphoprotein phosphatase calcineurin (CN) was phosphorylated by an activated form of Ca{sup 2+}/CaM-dependent protein kinase II (CaM-kinase II) incorporating approximately 1 mol of phosphoryl group/mol of catalytic subunit, in agreement with a value previously reported. Cyanogen bromide cleavage of radiolabeled CN followed by peptide fractionation using reverse-phase high-performance liquid chromatography yielded a single labeled peptide that contained a phosphoserine residue. Microsequencing of the peptide allowed both the determination of the cleavage cycle that released ({sup 32}P)phosphoserine and the identity of amino acids adjacent to it. Comparison of this sequence with the sequences of methionyl peptides deduced from the cDNA structure of CN allowed the phosphorylated serine to be uniquely identified. Interestingly, the phosphoserine exists in the sequence Met-Ala-Arg-Val-Phe-Ser(P)-Val-Leu-Arg-Glu, part of which lies within the putative CaM-binding sites. The phosphorylated serine residue was resistant to autocatalytic dephosphorylation, yet the slow rate of hydrolysis could be powerfully stimulated by effectors of CN phosphatase activity. The mechanism of dephosphorylation may be intramolecular since the initial rate was the same at phosphoCN concentrations of 2.5-250 nM.

  20. CaMKII inhibition in type II pneumocytes protects from bleomycin-induced pulmonary fibrosis by preventing Ca2+-dependent apoptosis.

    Science.gov (United States)

    Winters, Christopher J; Koval, Olha; Murthy, Shubha; Allamargot, Chantal; Sebag, Sara C; Paschke, John D; Jaffer, Omar A; Carter, A Brent; Grumbach, Isabella M

    2016-01-01

    The calcium and calmodulin-dependent kinase II (CaMKII) translates increases in intracellular Ca(2+) into downstream signaling events. Its function in pulmonary pathologies remains largely unknown. CaMKII is a well-known mediator of apoptosis and regulator of endoplasmic reticulum (ER) Ca(2+). ER stress and apoptosis of type II pneumocytes lead to aberrant tissue repair and progressive collagen deposition in pulmonary fibrosis. Thus we hypothesized that CaMKII inhibition alleviates fibrosis in response to bleomycin by attenuating apoptosis and ER stress of type II pneumocytes. We first established that CaMKII was strongly expressed in the distal respiratory epithelium, in particular in surfactant protein-C-positive type II pneumocytes, and activated after bleomycin instillation. We generated a novel transgenic model of inducible expression of the CaMKII inhibitor peptide AC3-I limited to type II pneumocytes (Tg SPC-AC3-I). Tg SPC-AC3-I mice were protected from development of pulmonary fibrosis after bleomycin exposure compared with wild-type mice. CaMKII inhibition also provided protection from apoptosis in type II pneumocytes in vitro and in vivo. Moreover, intracellular Ca(2+) levels and ER stress were increased by bleomycin and significantly blunted with CaMKII inhibition in vitro. These data demonstrate that CaMKII inhibition prevents type II pneumocyte apoptosis and development of pulmonary fibrosis in response to bleomycin. CaMKII inhibition may therefore be a promising approach to prevent or ameliorate the progression of pulmonary fibrosis. PMID:26545899

  1. Regulation of Voltage-Gated Ca2+ Currents by Ca2+/Calmodulin-dependent Protein Kinase II in Resting Sensory Neurons

    OpenAIRE

    Kostic, Sandra; Pan, Bin; Guo, Yuan; Yu, Hongwei; Sapunar, Damir; Kwok, Wai-Meng; Hudmon, Andy; Wu, Hsiang-en; Hogan, Quinn H

    2014-01-01

    Calcium/calmodulin-dependent protein kinase II (CaMKII) is recognized as a key element in encoding depolarization activity of excitable cells into facilitated voltage-gated Ca2+ channel (VGCC) function. Less is known about the participation of CaMKII in regulating VGCCs in resting cells. We examined constitutive CaMKII control of Ca2+ currents in peripheral sensory neurons acutely isolated from dorsal root ganglia (DRGs) of adult rats. The small molecule CaMKII inhibitor KN-93 (1.0μM) reduced...

  2. 3D Temperature Mapping of Solar Photospheric Fine Structure Using Ca II H Filtergrams

    CERN Document Server

    Henriques, V M J

    2012-01-01

    Context. The wings of the Ca II H and K lines provide excellent photospheric temperature diagnostics. At the Swedish 1-meter Solar Telescope the blue wing of Ca II H is scanned with a narrowband interference filter mounted on a rotation stage. This provides up to 0"10 spatial resolution filtergrams at high cadence that are concurrent with other diagnostics at longer wavelengths. Aims. The aim is to develop observational techniques that provide the photospheric temperature stratification at the highest spatial resolution possible and use those to compare simulations and observations at different heights. Methods. We use filtergrams in the Ca II H blue wing obtained with a tiltable interference filter at the SST. Synthetic observations are produced from 3D HD and 3D MHD numerical simulations and degraded to match the observations. The temperature structure obtained from applying the method to the synthetic data is compared with the known structure in the simulated atmospheres and with observations of an active ...

  3. Structure and evolutionary origin of Ca(2+-dependent herring type II antifreeze protein.

    Directory of Open Access Journals (Sweden)

    Yang Liu

    Full Text Available In order to survive under extremely cold environments, many organisms produce antifreeze proteins (AFPs. AFPs inhibit the growth of ice crystals and protect organisms from freezing damage. Fish AFPs can be classified into five distinct types based on their structures. Here we report the structure of herring AFP (hAFP, a Ca(2+-dependent fish type II AFP. It exhibits a fold similar to the C-type (Ca(2+-dependent lectins with unique ice-binding features. The 1.7 A crystal structure of hAFP with bound Ca(2+ and site-directed mutagenesis reveal an ice-binding site consisting of Thr96, Thr98 and Ca(2+-coordinating residues Asp94 and Glu99, which initiate hAFP adsorption onto the [10-10] prism plane of the ice lattice. The hAFP-ice interaction is further strengthened by the bound Ca(2+ through the coordination with a water molecule of the ice lattice. This Ca(2+-coordinated ice-binding mechanism is distinct from previously proposed mechanisms for other AFPs. However, phylogenetic analysis suggests that all type II AFPs evolved from the common ancestor and developed different ice-binding modes. We clarify the evolutionary relationship of type II AFPs to sugar-binding lectins.

  4. Solution chemistry effects on sorption behavior of 109Cd(II) on Ca-montmorillonite

    International Nuclear Information System (INIS)

    The sorption of radiocadmium on Ca-montmorillonite as a function of contact time, pH, ionic strength, foreign ions, humic acid (HA) and fulvic acid (FA) was studied using batch technique. The results demonstrated that the sorption of Cd(II) was dependent on ionic strength at pH 9. Outer-sphere surface complexation and/or ion exchange were the main mechanism of Cd(II) sorption on Ca-montmorillonite at low pH, whereas the sorption at high pH was mainly dominated via inner-sphere surface complexation. The sorption of Cd(II) on Ca-montmorillonite was dependent on foreign ions at low pH values, but was independent of foreign ions at high pH values. A positive effect of HA/FA on Cd(II) sorption was found at low pH values, whereas a negative effect was observed at high pH values. The thermodynamic parameters (i.e., ΔH0, ΔS0, ΔG0) were calculated from the temperature dependent sorption isotherms, and the results indicated that the sorption process of Cd(II) on Ca-montmorillonite was spontaneous and endothermic. (author)

  5. Simulation of Ca-Calmodulin-Dependent Protein Kinase II on Rabbit Ventricular Myocyte Ion Currents and Action Potentials

    OpenAIRE

    Grandi, Eleonora; Puglisi, Jose L.; Wagner, Stefan; Maier, Lars S.; Severi, Stefano; Bers, Donald M.

    2007-01-01

    Ca-calmodulin-dependent protein kinase II (CaMKII) was recently shown to alter Na+ channel gating and recapitulate a human Na+ channel genetic mutation that causes an unusual combined arrhythmogenic phenotype in patients: simultaneous long QT syndrome and Brugada syndrome. CaMKII is upregulated in heart failure where arrhythmias are common, and CaMKII inhibition can reduce arrhythmias. Thus, CaMKII-dependent channel modulation may contribute to acquired arrhythmic disease. We developed a Mark...

  6. The chemosensitizing agent lubeluzole binds calmodulin and inhibits Ca(2+)/calmodulin-dependent kinase II.

    Science.gov (United States)

    Bruno, Claudio; Cavalluzzi, Maria Maddalena; Rusciano, Maria Rosaria; Lovece, Angelo; Carrieri, Antonio; Pracella, Riccardo; Giannuzzi, Giulia; Polimeno, Lorenzo; Viale, Maurizio; Illario, Maddalena; Franchini, Carlo; Lentini, Giovanni

    2016-06-30

    An affinity capillary electrophoresis (ACE) method to estimate apparent dissociation constants between bovine brain calmodulin (CaM) and non-peptidic ligands was developed. The method was validated reproducing the dissociation constants of a number of well-known CaM ligands. In particular, the potent antagonist 125-C9 was ad hoc synthesized through an improved synthetic procedure. The ACE method was successfully applied to verify CaM affinity for lubeluzole, a well-known neuroprotective agent recently proved useful to potentiate the activity of anti-cancer drugs. Lubeluzole was slightly less potent than 125-C9 (Kd = 2.9 ± 0.7 and 0.47 ± 0.06 μM, respectively) and displayed Ca(2+)/calmodulin-dependent kinase II (CaMKII) inhibition (IC50 = 40 ± 1 μM). Possible binding modes of lubeluzole to CaM were explored by docking studies based on the X-ray crystal structures of several trifluoperazine-CaM complexes. An estimated dissociation constant in good agreement with the experimental one was found and the main aminoacidic residues and interactions contributing to complex formation were highlighted. The possibility that interference with Ca(2+) pathways may contribute to the previously observed chemosensitizing effects of lubeluzole on human ovarian adenocarcinoma and lung carcinoma cells are discussed. PMID:27043269

  7. Triplet exciton dynamics

    International Nuclear Information System (INIS)

    Results are presented of electron spin echo experiments combined with laser flash excitation on triplet states of aromatic molecules. Some of the theoretical and experimental aspects of the photoexcited triplet state are discussed in detail and the electron spin echo spectrometers and laser systems are described. All the experiments described in this thesis were performed at liquid helium temperatures. An account is given of the ESE experiments performed on the photoexcited, non-radiative, triplet state of pentacene in napthalene. This is an example of the ESE technique being used to ascertain the zero-field splitting parameters, the populating and depopulating rates, and the orientation of the pentacene molecules in the naphthalene host. A combination of high resolution laser flash excitation and electron-spin echoes in zero-magnetic field allowed the author to observe directly k(vector)→k(vector)' exciton scattering processes in the one-dimensional triplet excitons in tetrachlorobenzene for the first time. Additional experimental data about exciton scattering is provided and a study of the orientational dependence of the spin-lattice relaxation of the triplet excitons in an external magnetic field is described. (Auth.)

  8. Structural Properties of Human CaMKII Ca2+ /Calmodulin-Dependent Protein Kinase II using X-ray Crystallography

    Science.gov (United States)

    Cao, Yumeng Melody; McSpadden, Ethan; Kuriyan, John; Department of Molecular; Cell Biology; Department of Chemistry Team

    To this day, human memory storage remains a mystery as we can at most describe the process vaguely on a cellular level. Switch-like properties of Calcium/Calmodulin-Dependent Protein Kinase II make it a leading candidate in understanding the molecular basis of human memory. The protein crystal was placed in the beam of a synchrotron source and the x-ray crystallography data was collected as reflections on a diffraction pattern that undergo Fourier transform to obtain the electron density. We observed two drastic differences from our solved structure at 2.75Å to a similar construct of the mouse CaMKII association domain. Firstly, our structure is a 6-fold symmetric dodecamer, whereas the previously published construct was a 7-fold symmetric tetradecamer. This suggests the association domain of human CaMKII is a dynamic structure that is triggered subunit exchange process. Secondly, in our structure the N-terminal tag is docked as an additional beta-strand on an uncapped beta-sheet present in each association domain protomer. This is concrete evidence of the involvement of the polypeptide docking site in the molecular mechanism underlining subunit exchange. In the future, we would like to selectively inhibit the exchange process while not disrupting the other functionalities of CaMKII.

  9. Time-resolved photoelectron spectroscopy of a dinuclear Pt(II) complex: Tunneling autodetachment from both singlet and triplet excited states of a molecular dianion

    International Nuclear Information System (INIS)

    Time-resolved pump-probe photoelectron spectroscopy has been used to study the relaxation dynamics of gaseous [Pt2(μ-P2O5H2)4 + 2H]2− after population of its first singlet excited state by 388 nm femtosecond laser irradiation. In contrast to the fluorescence and phosphorescence observed in condensed phase, a significant fraction of the photoexcited isolated dianions decays by electron loss to form the corresponding monoanions. Our transient photoelectron data reveal an ultrafast decay of the initially excited singlet 1A2u state and concomitant rise in population of the triplet 3A2u state, via sub-picosecond intersystem crossing (ISC). We find that both of the electronically excited states are metastably bound behind a repulsive Coulomb barrier and can decay via delayed autodetachment to yield electrons with characteristic kinetic energies. While excited state tunneling detachment (ESETD) from the singlet 1A2u state takes only a few picoseconds, ESETD from the triplet 3A2u state is much slower and proceeds on a time scale of hundreds of nanoseconds. The ISC rate in the gas phase is significantly higher than in solution, which can be rationalized in terms of changes to the energy dissipation mechanism in the absence of solvent molecules. [Pt2(μ-P2O5H2)4 + 2H]2− is the first example of a photoexcited multianion for which ESETD has been observed following ISC

  10. Tracers of Chromospheric Structure. I. Observations of Ca II K and Hα in M Dwarfs

    Science.gov (United States)

    Walkowicz, Lucianne M.; Hawley, Suzanne L.

    2009-02-01

    We report on our observing program4This paper is based on observations obtained with the Apache Point Observatory 3.5 m telescope, which is owned and operated by the Astrophysical Research Consortium. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. to capture simultaneous spectra of Ca II and Balmer lines in a sample of nearby M3 dwarfs. Our goal is to investigate the chromospheric temperature structure required to produce these lines at the observed levels. We find a strong positive correlation between instantaneous measurements of Ca II K and the Balmer lines in active stars, although these lines may not be positively correlated in time-resolved measurements. The relationship between Hα and Ca II K remains ambiguous for weak and intermediate activity stars, with Hα absorption corresponding to a range of Ca II K emission. A similar relationship is also observed between Ca II K and the higher-order Balmer lines. As our sample consists of a single spectral type, correlations between these important chromospheric tracers cannot be ascribed to continuum effects, as suggested by other authors. These data confirm prior nonsimultaneous observations of the Hα line behavior with increasing activity, showing an initial increase in the Hα absorption with increasing Ca II K emission, prior to Hα filling in and eventually becoming a pure emission line in the most active stars. We also compare our optical measurements with archival UV and X-ray measurements, finding a positive correlation between the chromospheric and coronal emission for both high and intermediate activity stars. We compare our results with previous determinations of the active fraction of low-mass stars

  11. Rat vas deferens SERCA2 is modulated by Ca2+/calmodulin protein kinase II-mediated phosphorylation

    Directory of Open Access Journals (Sweden)

    J.B.R. Rodriguez

    2013-03-01

    Full Text Available Ca2+ pumps are important players in smooth muscle contraction. Nevertheless, little information is available about these pumps in the vas deferens. We have determined which subtype of sarco(endoplasmic reticulum Ca2+-ATPase isoform (SERCA is expressed in rat vas deferens (RVD and its modulation by calmodulin (CaM-dependent mechanisms. The thapsigargin-sensitive Ca2+-ATPase from a membrane fraction containing the highest SERCA levels in the RVD homogenate has the same molecular mass (∼115 kDa as that of SERCA2 from the rat cerebellum. It has a very high affinity for Ca2+ (Ca0.5 = 780 nM and a low sensitivity to vanadate (IC50 = 41 µM. These facts indicate that SERCA2 is present in the RVD. Immunoblotting for CaM and Ca2+/calmodulin-dependent protein kinase II (CaMKII showed the expression of these two regulatory proteins. Ca2+ and CaM increased serine-phosphorylated residues of the 115-kDa protein, indicating the involvement of CaMKII in the regulatory phosphorylation of SERCA2. Phosphorylation is accompanied by an 8-fold increase of thapsigargin-sensitive Ca2+ accumulation in the lumen of vesicles derived from these membranes. These data establish that SERCA2 in the RVD is modulated by Ca2+ and CaM, possibly via CaMKII, in a process that results in stimulation of Ca2+ pumping activity.

  12. Rat vas deferens SERCA2 is modulated by Ca2+/calmodulin protein kinase II-mediated phosphorylation

    International Nuclear Information System (INIS)

    Ca2+ pumps are important players in smooth muscle contraction. Nevertheless, little information is available about these pumps in the vas deferens. We have determined which subtype of sarco(endo)plasmic reticulum Ca2+-ATPase isoform (SERCA) is expressed in rat vas deferens (RVD) and its modulation by calmodulin (CaM)-dependent mechanisms. The thapsigargin-sensitive Ca2+-ATPase from a membrane fraction containing the highest SERCA levels in the RVD homogenate has the same molecular mass (∼115 kDa) as that of SERCA2 from the rat cerebellum. It has a very high affinity for Ca2+ (Ca0.5 = 780 nM) and a low sensitivity to vanadate (IC50 = 41 µM). These facts indicate that SERCA2 is present in the RVD. Immunoblotting for CaM and Ca2+/calmodulin-dependent protein kinase II (CaMKII) showed the expression of these two regulatory proteins. Ca2+ and CaM increased serine-phosphorylated residues of the 115-kDa protein, indicating the involvement of CaMKII in the regulatory phosphorylation of SERCA2. Phosphorylation is accompanied by an 8-fold increase of thapsigargin-sensitive Ca2+ accumulation in the lumen of vesicles derived from these membranes. These data establish that SERCA2 in the RVD is modulated by Ca2+ and CaM, possibly via CaMKII, in a process that results in stimulation of Ca2+ pumping activity

  13. Molecular determinants for cardiovascular TRPC6 channel regulation by Ca2+/calmodulin-dependent kinase II

    DEFF Research Database (Denmark)

    Shi, Juan; Geshi, Naomi; Takahashi, Shinichi;

    2013-01-01

    The molecular mechanism underlying Ca2+/calmodulin (CaM)-dependent kinase II (CaMKII)-mediated regulation of the mouse transient receptor potential channel TRPC6 was explored by chimera, deletion and site-directed mutagenesis approaches. Induction of currents (ICCh) in TRPC6-expressing HEK293 cel...... essential for CaMKII-mediated regulation of TRPC6 channels. This mechanism may be of physiological significance in a native environment such as in vascular smooth muscle cells....

  14. ON-DISK COUNTERPARTS OF TYPE II SPICULES IN THE Ca II 854.2 nm AND Hα LINES

    International Nuclear Information System (INIS)

    Recently, a second type of spicules was discovered at the solar limb with the Solar Optical Telescope onboard the Japanese Hinode spacecraft. These previously unrecognized type II spicules are thin chromospheric jets that are shorter lived (10-60 s) and that show much higher apparent upward velocities (of order 50-100 km s-1) than the classical spicules. Since they have been implicated in providing hot plasma to coronal loops, their formation, evolution, and properties are important ingredients for a better understanding of the mass and energy balance of the low solar atmosphere. Here, we report on the discovery of the disk counterparts of type II spicules using spectral imaging data in the Ca II 854.2 nm and Hα lines with the CRisp Imaging SpectroPolarimeter at the Swedish Solar Telescope in La Palma. We find rapid blueward excursions in the line profiles of both chromospheric lines that correspond to thin, jet-like features that show apparent velocities of order 50 km s-1. These blueward excursions seem to form a separate absorbing component with Doppler shifts of order 20 and 50 km s-1 for the Ca II 854.2 nm and Hα line, respectively. We show that the appearance, lifetimes, longitudinal and transverse velocities, and occurrence rate of these rapid blue excursions on the disk are very similar to those of the type II spicules at the limb. A detailed study of the spectral line profiles in these events suggests that plasma is accelerated along the jet, and plasma is being heated throughout the short lifetime of the event.

  15. Ca II H sunspot tomography from the photosphere to the chromosphere

    Science.gov (United States)

    Henriques, V. M. J.; Kiselman, D.

    2013-09-01

    Aims: We aim at gaining insight into the thermal properties of different small-scale structures related to sunspots. Methods: We use filtergrams in the Ca ii H filter at the Swedish 1-m Solar Telescope to study the relationship between fine structure at different heights in a sunspot. Results: The methods for destretching and aligning the different image data work well. The magnetic spine structure in the outer parts of the sunspot penumbra is found to be associated with higher intensities in the Ca ii H wing passbands but with less steep vertical temperature gradients. Dark lanes in a light bridge behave very similarly to dark cores in penumbral filaments. Fibril structures are seen in the line-core images over the umbra and penumbra. Conclusions: The observations add support to the idea that penumbral filaments, light bridges, and umbral dots are caused by similar processes of overturning convection. Observations in the Ca ii H & K wings are a promising observable, complementing others, for testing simulation results for sunspots at high spatial resolution.

  16. Analysis of Ca II K spectroheliogram time-series for solar irradiance studies

    Science.gov (United States)

    Ermolli, Ilaria; Krivova, Natalie; Solanki, Sami K.

    Historic Ca II K observations constitute an extremely valuable resource for many research topics, including investigations of solar activity and irradiance variations on century timescales. In fact, the intensities measured on these observations can serve as proxies for magnetic activity, due to the strong correlation found between the Ca II K emission and the line-of-sight magnetic flux density. We analyzed three time-series of historic Ca II K observations, specifically those obtained by the digitization of the Arcetri, Kodaikanal, and Mt Wilson spectroheliohram archives. We examined the quality of these data, in order to estimate their value for irradiance studies focusing on time-scales longer than the solar cycle. We employ different processing techniques in order to investigate whether uniform results on the evolution of the solar magnetic field, both in quiet and active regions, can be obtained for the three analyzed series. ——-Session A1.1 Atmosphere Chemistry and Physics (i) Solar Spectral Irradiance Variations and Their Influence on the Earth's Atmosphere

  17. Long-term Synoptic Observations of Ca II K and Magnetic Flux

    Science.gov (United States)

    Bertello, L.; Pevtsov, A. A.; Tlatov, A. G.

    2016-04-01

    Long-term synoptic observations in the resonance line of Ca II K and measurements of the solar magnetic flux over several decades constitute a fundamental database for a variety of retrospective analyzes of the state of the solar magnetism. These data archives may also hold the key for untangling some of the mysteries behind the solar dynamo, which in turn could result in a better predictive capability of current dynamo models. Synoptic Ca II K observations began in 1907 at the Kodaikanal observatory (India) and in 1915 at the Mt Wilson (California, USA) solar observatory. By the early 1970s a number of synoptic programs for solar magnetic observations were established that provided full disk magnetograms. These programs include measurements carried out at the Mt Wilson 150-foot solar tower, Wilcox observatory (California, USA), and by the National Solar Observatory (NSO, USA). Today the NSO is continuing these observations through its Synoptic Optical Long-term Investigations of the Sun (SOLIS) facility. We will review some of these historical observations, their properties, and their importance for understanding the behavior of the solar magnetic field over multidecadal time scales. We will also show recent results about using Ca II K spectroheliograms and sunspot magnetic field measurements to reconstruct homogeneous series of pseudo-magnetograms prior the magnetograph era.

  18. Time-resolved photoelectron spectroscopy of a dinuclear Pt(II) complex: Tunneling autodetachment from both singlet and triplet excited states of a molecular dianion

    Energy Technology Data Exchange (ETDEWEB)

    Winghart, Marc-Oliver, E-mail: marc-oliver.winghart@kit.edu; Unterreiner, Andreas-Neil [Institute of Physical Chemistry, Karlsruhe Institute of Technology, P.O. Box 6980, 76049 Karlsruhe (Germany); Yang, Ji-Ping [Institute of Physical Chemistry, Karlsruhe Institute of Technology, P.O. Box 6980, 76049 Karlsruhe (Germany); School of Sciences, Hefei University of Technology, Hefei 230009 (China); Vonderach, Matthias [Centre for Proteome Research, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB (United Kingdom); Huang, Dao-Ling; Wang, Lai-Sheng [Department of Chemistry, Brown University, Providence, Rhode Island 02912 (United States); Kruppa, Sebastian; Riehn, Christoph [Fachbereich Chemie und Landesforschungszentrum OPTIMAS, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 52–54, 67663 Kaiserslautern (Germany); Kappes, Manfred M., E-mail: manfred.kappes@kit.edu [Institute of Physical Chemistry, Karlsruhe Institute of Technology, P.O. Box 6980, 76049 Karlsruhe (Germany); Institute of Nanotechnology, Karlsruhe Institute of Technology, P.O. Box 3640, 76021 Karlsruhe (Germany)

    2016-02-07

    Time-resolved pump-probe photoelectron spectroscopy has been used to study the relaxation dynamics of gaseous [Pt{sub 2}(μ-P{sub 2}O{sub 5}H{sub 2}){sub 4} + 2H]{sup 2−} after population of its first singlet excited state by 388 nm femtosecond laser irradiation. In contrast to the fluorescence and phosphorescence observed in condensed phase, a significant fraction of the photoexcited isolated dianions decays by electron loss to form the corresponding monoanions. Our transient photoelectron data reveal an ultrafast decay of the initially excited singlet {sup 1}A{sub 2u} state and concomitant rise in population of the triplet {sup 3}A{sub 2u} state, via sub-picosecond intersystem crossing (ISC). We find that both of the electronically excited states are metastably bound behind a repulsive Coulomb barrier and can decay via delayed autodetachment to yield electrons with characteristic kinetic energies. While excited state tunneling detachment (ESETD) from the singlet {sup 1}A{sub 2u} state takes only a few picoseconds, ESETD from the triplet {sup 3}A{sub 2u} state is much slower and proceeds on a time scale of hundreds of nanoseconds. The ISC rate in the gas phase is significantly higher than in solution, which can be rationalized in terms of changes to the energy dissipation mechanism in the absence of solvent molecules. [Pt{sub 2}(μ-P{sub 2}O{sub 5}H{sub 2}){sub 4} + 2H]{sup 2−} is the first example of a photoexcited multianion for which ESETD has been observed following ISC.

  19. Alkyl sulfonic acide hydrazides: Synthesis, characterization, computational studies and anticancer, antibacterial, anticarbonic anhydrase II (hCA II) activities

    Science.gov (United States)

    O. Ozdemir, Ummuhan; İlbiz, Firdevs; Balaban Gunduzalp, Ayla; Ozbek, Neslihan; Karagoz Genç, Zuhal; Hamurcu, Fatma; Tekin, Suat

    2015-11-01

    Methane sulfonic acide hydrazide, CH3SO2NHNH2 (1), ethane sulfonic acide hydrazide, CH3CH2SO2NHNH2 (2), propane sulfonic acide hydrazide, CH3CH2CH2SO2NHNH2 (3) and butane sulfonic acide hydrazide, CH3CH2CH2CH2SO2NHNH2 (4) have been synthesized as homologous series and characterized by using elemental analysis, spectrophotometric methods (1H-13C NMR, FT-IR, LC-MS). In order to gain insight into the structure of the compounds, we have performed computational studies by using 6-311G(d, p) functional in which B3LYP functional were implemented. The geometry of the sulfonic acide hydrazides were optimized at the DFT method with Gaussian 09 program package. A conformational analysis of compounds were performed by using NMR theoretical calculations with DFT/B3LYP/6-311++G(2d, 2p) level of theory by applying the (GIAO) approach. The anticancer activities of these compounds on MCF-7 human breast cancer cell line investigated by comparing IC50 values. The antibacterial activities of synthesized compounds were studied against Gram positive bacteria; Staphylococcus aureus ATCC 6538, Bacillus subtilis ATCC 6633, Bacillus cereus NRRL-B-3711, Enterococcus faecalis ATCC 29212 and Gram negative bacteria; Escherichia coli ATCC 11230, Pseudomonas aeruginosa ATCC 15442, Klebsiella pneumonia ATCC 70063 by using the disc diffusion method. The inhibition activities of these compounds on carbonic anhydrase II enzyme (hCA II) have been investigated by comparing IC50 and Ki values. The biological activity screening shows that butane sulfonic acide hydrazide (4) has more activity than the others against tested breast cancer cell lines MCF-7, Gram negative/Gram positive bacteria and carbonic anhydrase II (hCA II) isoenzyme.

  20. TRIO (Triplet Ionospheric Observatory) Mission

    Science.gov (United States)

    Lee, D.; Seon, J.; Jin, H.; Kim, K.; Lee, J.; Jang, M.; Pak, S.; Kim, K.; Lin, R. P.; Parks, G. K.; Halekas, J. S.; Larson, D. E.; Eastwood, J. P.; Roelof, E. C.; Horbury, T. S.

    2009-12-01

    Triplets of identical cubesats will be built to carry out the following scientific objectives: i) multi-observations of ionospheric ENA (Energetic Neutral Atom) imaging, ii) ionospheric signature of suprathermal electrons and ions associated with auroral acceleration as well as electron microbursts, and iii) complementary measurements of magnetic fields for particle data. Each satellite, a cubesat for ion, neutral, electron, and magnetic fields (CINEMA), is equipped with a suprathermal electron, ion, neutral (STEIN) instrument and a 3-axis magnetometer of magnetoresistive sensors. TRIO is developed by three institutes: i) two CINEMA by Kyung Hee University (KHU) under the WCU program, ii) one CINEMA by UC Berkeley under the NSF support, and iii) three magnetometers by Imperial College, respectively. Multi-spacecraft observations in the STEIN instruments will provide i) stereo ENA imaging with a wide angle in local times, which are sensitive to the evolution of ring current phase space distributions, ii) suprathermal electron measurements with narrow spacings, which reveal the differential signature of accelerated electrons driven by Alfven waves and/or double layer formation in the ionosphere between the acceleration region and the aurora, and iii) suprathermal ion precipitation when the storm-time ring current appears. In addition, multi-spacecraft magnetic field measurements in low earth orbits will allow the tracking of the phase fronts of ULF waves, FTEs, and quasi-periodic reconnection events between ground-based magnetometer data and upstream satellite data.

  1. Experiments TGV I (double-beta decay of 48Ca) and TGV II (double-beta decay of 106Cd and 48Ca)

    Science.gov (United States)

    Štekl, I.; Čermák, P.; Beneš, P.; Brudanin, V. B.; Rukhadze, N. I.; Egorov, V. G.; Kovalenko, V. E.; Kovalík, A.; Salamatin, A. V.; Tsoupko-Sitnikov, V. V.; Vylov, Ts.; Briancon, Ch.; Šimkovic, F.

    2000-04-01

    Present status of experiments TGV I and TGV II is given. The TGV I collaboration has studied the double-beta decay of 48Ca with a low-background and high sensitivity Ge multi-detector spectrometer TGV (Telescope Germanium Vertical). The preliminary results of years and years (90% CL) for double-beta decay of 48 Ca has been found after the processing of experimental data obtained after 8700 hours of measuring time using approximately 1 gramme of 48Ca. The aim of the experiment TGV II is the development of the experimental methods, construction of spectrometers and measurement of the decay (++, β+/EC, EC/EC) of 106Cd particularly the 2νEC/EC mode. The theoretical description and performance of the TGV II spectrometer are also given.

  2. A dynamic model of interactions of Ca2+, calmodulin, and catalytic subunits of Ca2+/calmodulin-dependent protein kinase II.

    Directory of Open Access Journals (Sweden)

    Shirley Pepke

    2010-02-01

    Full Text Available During the acquisition of memories, influx of Ca2+ into the postsynaptic spine through the pores of activated N-methyl-D-aspartate-type glutamate receptors triggers processes that change the strength of excitatory synapses. The pattern of Ca2+influx during the first few seconds of activity is interpreted within the Ca2+-dependent signaling network such that synaptic strength is eventually either potentiated or depressed. Many of the critical signaling enzymes that control synaptic plasticity,including Ca2+/calmodulin-dependent protein kinase II (CaMKII, are regulated by calmodulin, a small protein that can bindup to 4 Ca2+ ions. As a first step toward clarifying how the Ca2+-signaling network decides between potentiation or depression, we have created a kinetic model of the interactions of Ca2+, calmodulin, and CaMKII that represents our best understanding of the dynamics of these interactions under conditions that resemble those in a postsynaptic spine. We constrained parameters of the model from data in the literature, or from our own measurements, and then predicted time courses of activation and autophosphorylation of CaMKII under a variety of conditions. Simulations showed that species of calmodulin with fewer than four bound Ca2+ play a significant role in activation of CaMKII in the physiological regime,supporting the notion that processing of Ca2+ signals in a spine involves competition among target enzymes for binding to unsaturated species of CaM in an environment in which the concentration of Ca2+ is fluctuating rapidly. Indeed, we showed that dependence of activation on the frequency of Ca2+ transients arises from the kinetics of interaction of fluctuating Ca2+with calmodulin/CaMKII complexes. We used parameter sensitivity analysis to identify which parameters will be most beneficial to measure more carefully to improve the accuracy of predictions. This model provides a quantitative base from which to build more complex dynamic

  3. On the potential value of Ca II K spectroheliogram time-series for solar activity and irradiance studies

    OpenAIRE

    I. Ermolli; Solanki, S. K.; Tlatov, A.G.; Krivova, N. A.; Ulrich, R. K.; J. Singh

    2008-01-01

    Various observatories around the globe started regular full-disk imaging of the solar atmosphere in the Ca II K line since the early decades of the 20th century. The archives made by these observations have the potential of providing far more detailed information on solar magnetism than just the sunspot number and area records to which most studies of solar activity and irradiance changes are restricted. We evaluate the image contents of three Ca II K spectroheliogram time-series, specificall...

  4. Ocular dominance plasticity is stably maintained in the absence of α calcium calmodulin kinase IICaMKII) autophosphorylation

    OpenAIRE

    Sharif A Taha; Stryker, Michael P.

    2005-01-01

    The molecule α calcium calmodulin kinase IICaMKII) is known to play a fundamental role in the induction of many forms of synaptic plasticity. A major theory of αCaMKII function proposes that autophosphorylation of the molecule mediates not only the induction but also the maintenance of synaptic plasticity. To test this hypothesis, we assessed ocular dominance plasticity in genetically engineered mice that carry a mutation preventing autophosphorylation of αCaMKII. These mutant mice are def...

  5. Comparison Among Ca II K Spectroheliogram Time Series with an Application to Solar Activity Studies

    Science.gov (United States)

    Ermolli, I.; Solanki, S. K.; Tlatov, A. G.; Krivova, N. A.; Ulrich, R. K.; Singh, J.

    2009-06-01

    Various observatories around the globe started regular full-disk imaging of the solar atmosphere in the Ca II K line in the early decades of the 20th century. The archives made by these observations have the potential of providing far more detailed information on solar magnetism than just the sunspot number and area records to which most studies of solar activity and irradiance changes are restricted. We evaluate the image quality and contents of three Ca II K spectroheliogram time series, specifically those obtained by the digitization of the Arcetri, Kodaikanal, and Mt Wilson photographic archives, in order to estimate their value for studies focusing on timescales longer than the solar cycle. We analyze the quality of these data and compare the results obtained with those achieved for similar present-day observations taken with the Meudon spectroheliograph and with the Rome-PSPT. We also investigate whether image-segmentation techniques, such as those developed for identification of plage regions on present-day Ca II K observations, can be used to process historic series. We show that historic data suffer from stronger geometrical distortions and photometric uncertainties than similar present-day observations. The latter uncertainties mostly originate from the photographic calibration of the original data and from stray-light effects. We also show that the image contents of the three analyzed series vary in time. These variations are probably due to instrument changes and aging of the spectrographs used, as well as changes of the observing programs. The segmentation technique tested in this study gives reasonably consistent results for the three analyzed series after application of a simple photographic calibration. Although the plage areas measured from the three analyzed series differ somewhat, the difference to previously published results is larger.

  6. Rat vas deferens SERCA2 is modulated by Ca{sup 2+}/calmodulin protein kinase II-mediated phosphorylation

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, J.B.R.; Muzi-Filho, H. [Programa de Farmacologia e Inflamação, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Valverde, R.H.F. [Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Quintas, L.E.M. [Programa de Farmacologia e Inflamação, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Noel, F. [Programa de Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Einicker-Lamas, M. [Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Rio de Janeiro, RJ (Brazil); Cunha, V.M.N. [Programa de Farmacologia e Inflamação, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil)

    2013-03-19

    Ca{sup 2+} pumps are important players in smooth muscle contraction. Nevertheless, little information is available about these pumps in the vas deferens. We have determined which subtype of sarco(endo)plasmic reticulum Ca{sup 2+}-ATPase isoform (SERCA) is expressed in rat vas deferens (RVD) and its modulation by calmodulin (CaM)-dependent mechanisms. The thapsigargin-sensitive Ca{sup 2+}-ATPase from a membrane fraction containing the highest SERCA levels in the RVD homogenate has the same molecular mass (∼115 kDa) as that of SERCA2 from the rat cerebellum. It has a very high affinity for Ca{sup 2+} (Ca{sub 0.5} = 780 nM) and a low sensitivity to vanadate (IC{sub 50} = 41 µM). These facts indicate that SERCA2 is present in the RVD. Immunoblotting for CaM and Ca{sup 2+}/calmodulin-dependent protein kinase II (CaMKII) showed the expression of these two regulatory proteins. Ca{sup 2+} and CaM increased serine-phosphorylated residues of the 115-kDa protein, indicating the involvement of CaMKII in the regulatory phosphorylation of SERCA2. Phosphorylation is accompanied by an 8-fold increase of thapsigargin-sensitive Ca{sup 2+} accumulation in the lumen of vesicles derived from these membranes. These data establish that SERCA2 in the RVD is modulated by Ca{sup 2+} and CaM, possibly via CaMKII, in a process that results in stimulation of Ca{sup 2+} pumping activity.

  7. Phasic Triplet Markov Chains.

    Science.gov (United States)

    El Yazid Boudaren, Mohamed; Monfrini, Emmanuel; Pieczynski, Wojciech; Aïssani, Amar

    2014-11-01

    Hidden Markov chains have been shown to be inadequate for data modeling under some complex conditions. In this work, we address the problem of statistical modeling of phenomena involving two heterogeneous system states. Such phenomena may arise in biology or communications, among other fields. Namely, we consider that a sequence of meaningful words is to be searched within a whole observation that also contains arbitrary one-by-one symbols. Moreover, a word may be interrupted at some site to be carried on later. Applying plain hidden Markov chains to such data, while ignoring their specificity, yields unsatisfactory results. The Phasic triplet Markov chain, proposed in this paper, overcomes this difficulty by means of an auxiliary underlying process in accordance with the triplet Markov chains theory. Related Bayesian restoration techniques and parameters estimation procedures according to the new model are then described. Finally, to assess the performance of the proposed model against the conventional hidden Markov chain model, experiments are conducted on synthetic and real data. PMID:26353069

  8. Phage inactivation by triplet acetone

    International Nuclear Information System (INIS)

    The exposure of lambda phage to triplet acetone is studied. The triplet acetone is obtained from aerobic oxidation of isobutanal catalysed by peroxidase. A decrease of lambda phage ability to infect Escherichia coli is reported, perhaps, partially due to the possible production of lesions in the phage genome. (M.A.C.)

  9. Dynamo Sensitivity in Solar Analogs with 50 Years of Ca II H & K Activity

    CERN Document Server

    Egeland, Ricky; Baliunas, Sallie; Hall, Jeffrey C; Pevtsov, Alexei A; Henry, Gregory W

    2016-01-01

    The Sun has a steady 11-year cycle in magnetic activity most well-known by the rising and falling in the occurrence of dark sunspots on the solar disk in visible bandpasses. The 11-year cycle is also manifest in the variations of emission in the Ca II H & K line cores, due to non-thermal (i.e. magnetic) heating in the lower chromosphere. The large variation in Ca II H & K emission allows for study of the patterns of long-term variability in other stars thanks to synoptic monitoring with the Mount Wilson Observatory HK photometers (1966-2003) and Lowell Observatory Solar-Stellar Spectrograph (1994-present). Overlapping measurements for a set of 27 nearby solar-analog (spectral types G0-G5) stars were used to calibrate the two instruments and construct time series of magnetic activity up to 50 years in length. Precise properties of fundamental importance to the dynamo are available from Hipparcos, the Geneva-Copenhagen Survey, and CHARA interferometry. Using these long time series and measurements of fu...

  10. On the migration of Ca II H bright points in the internetwork

    CERN Document Server

    Jafarzadeh, S; Solanki, S K; Pietarila, A; Feller, A; Lagg, A; Gandorfer, A

    2014-01-01

    The migration of magnetic bright point-like features (MBP) in the lower solar atmosphere reflects the dispersal of magnetic flux as well as the horizontal flows of the atmospheric layer they are embedded in. We analyse trajectories of the proper motion of intrinsically magnetic, isolated internetwork Ca II H MBPs (mean lifetime 461 +- 9 sec) to obtain their diffusivity behaviour. We use seeing-free high spatial and temporal resolution image sequences of quiet-Sun, disc-centre observations obtained in the Ca II H 3968 {\\AA} passband of the Sunrise Filter Imager (SuFI) onboard the Sunrise balloon-borne solar observatory. Small MBPs in the internetwork are automatically tracked. The trajectory of each MBP is then calculated and described by a diffusion index ({\\gamma}) and a diffusion coefficient (D). We further explore the distribution of the diffusion indices with the help of a Monte Carlo simulation. We find {\\gamma} = 1.69 +- 0.08 and D = 257 +- 32 km^2/s averaged over all MBPs. Trajectories of most MBPs are...

  11. Butterfly Diagram and Carrington Maps for Century-Long Ca II K Spectroheliograms from Kodaikanal Observatory

    CERN Document Server

    Chatterjee, Subhamoy; Ravindra, B

    2016-01-01

    The century-long (1907-2007) Ca II K spectroheliograms from Kodaikanal Solar Observatory (KSO) are calibrated, processed and analysed in the present study to follow the evolution of bright on disc structures called plages, the possible representatives of magnetic activity on the Sun. This has been the longest dataset studied in Ca II K till date covering about 9.5 cycles of 11 year periods. Plages were segmented with area $\\geq 1\\:\\textrm {arcmin}^2$ using global thresholds for individual full disc images and subsequent application of morphological closing operation. Plage index was calculated and seen to have close positive correlation with fractional disc area covered by plages. The newly generated plage area cycle (from KSO) was compared with the same from Mount Wilson observatory (Correlation~$95.6\\%$) for the overlapping years i.e. 1915-2000. Study illustrated time-latitude distribution of plage centroids rendering butterfly diagram (as observed for sunspots). The 3D visualisation of the diagram showed o...

  12. Solar Activity and Irradiance Studies with Ca II Spectroheliograms: Potential and Problems

    Science.gov (United States)

    Ermolli, I.; Tlatov, A.; Solanki, S. K.; Krivova, N. A.; Singh, J.

    2007-05-01

    Various observatories around the globe carried out synoptic full-disk observations of the Sun since the beginning of the 20th century. The archives created by these observations, especially those including Ca II spectroheliograms, have the potential of providing far more detailed information on solar activity than the indices usually used to study activity variations, solar cycle and irradiance changes. However, these data suffer significantly from various problems including numerous defects in the photographic plates, missing or inaccurate calibration of the blackening curve, changes in the positioning of the exit slit with respect to the spectral line and variable seeing. Here we discuss the quality of images obtained by the digitization of three historic Ca II K time series, specifically those stored by the Arcetri, Kodaikanal and Mt Wilson Observatories. The aim of this work is to evaluate the potential value of these data for studies of solar activity and variability. It also shows the importance of the detailed and accurate image processing technique, in order to obtain uniform and trustable results from images coming from different historic archives.

  13. Mixed ligand complexes of alkaline earth metals: Part XII. Mg(II, Ca(II, Sr(II and Ba(II complexes with 5-chlorosalicylaldehyde and salicylaldehyde or hydroxyaromatic ketones

    Directory of Open Access Journals (Sweden)

    MITHLESH AGRAWAL

    2002-04-01

    Full Text Available The reactions of alkaline earth metal chlorides with 5-chlorosalicylaldehyde and salicylaldehyde, 2-hydroxyacetophenone or 2-hydroxypropiophenone have been carried out in 1 : 1 : 1 mole ratio and the mixed ligand complexes of the type MLL’(H2O2 (where M = Mg(II, Ca(II, Sr(II and Ba(II, HL = 5-chlorosalicylaldehyde and HL’ = salicylaldehyde, 2-hydroxyacetophenone or 2-hydroxypropiophenone have been isolated. These complexes were characterized by TLC, conductance measurements, IR and 1H-NMR spectra.

  14. Modulation pf pulmonary surfactant secretion from alveolar type II cells by cytoplasmic free calcium ([Ca2+]/sub i/)

    International Nuclear Information System (INIS)

    Ca2+ is regulator of a variety of cellular functions including exocytosis. TPA and terbutaline have been shown to stimulate surfactant secretion from alveolar type II cells. The authors examined changes in [Ca2+]/sub i/ and surfactant secretion by secretagogues in primary culture of alveolar type II cells. Cells were isolated from adult rats and were cultured for 24 h with 3H-choline to label phosphatidylcholine. Percent secretion was determined by counting the lipids of cells and medium; cytotoxicity was excluded by measuring lactate dehydrogenase as cells and medium. [Ca2+]/sub i/ was determined by measuring quin2 fluroescence of cells cultured on a glass coverslip. Ionomycin increased secretion as well as [Ca2+] in dose dependent manner at the concentration from 25 to 400 nM. Ionomycin (50 nM) increased terbutaline-induced secretion in a synergistic manner but only increased TPA-induced secretion in an additive manner. Terbutaline mobilized [Ca2+]/sub i/ from intracellular stores and increased [Ca2+]/sub i/ by 20% from a basal level of 140 nM. TPA itself did not change [Ca2+]/sub i/ but inhibited the effect of terbutaline on [Ca2+]/sub i/. Loading of quin2 in the absence of extracellular calcium lowered [Ca2+]/sub i/ from 143 nM to 31 nM. Lowering [Ca2+]/sub i/ inhibited TPA- or terbutaline-induced secretion by 22% and 40% respectively. These results indicate that [Ca2+]/sub i/ effects cAMp-induced secretion more than protein kinase C-mediated secretion in alveolar type II cells

  15. Modulation pf pulmonary surfactant secretion from alveolar type II cells by cytoplasmic free calcium ((Ca/sup 2 +/)/sub i/)

    Energy Technology Data Exchange (ETDEWEB)

    Sano, K.; Voelker, D.R.; Mason, R.J.

    1986-05-01

    Ca/sup 2 +/ is regulator of a variety of cellular functions including exocytosis. TPA and terbutaline have been shown to stimulate surfactant secretion from alveolar type II cells. The authors examined changes in (Ca/sup 2 +/)/sub i/ and surfactant secretion by secretagogues in primary culture of alveolar type II cells. Cells were isolated from adult rats and were cultured for 24 h with /sup 3/H-choline to label phosphatidylcholine. Percent secretion was determined by counting the lipids of cells and medium; cytotoxicity was excluded by measuring lactate dehydrogenase as cells and medium. (Ca/sup 2 +/)/sub i/ was determined by measuring quin2 fluroescence of cells cultured on a glass coverslip. Ionomycin increased secretion as well as (Ca/sup 2 +/) in dose dependent manner at the concentration from 25 to 400 nM. Ionomycin (50 nM) increased terbutaline-induced secretion in a synergistic manner but only increased TPA-induced secretion in an additive manner. Terbutaline mobilized (Ca/sup 2 +/)/sub i/ from intracellular stores and increased (Ca/sup 2 +/)/sub i/ by 20% from a basal level of 140 nM. TPA itself did not change (Ca/sup 2 +/)/sub i/ but inhibited the effect of terbutaline on (Ca/sup 2 +/)/sub i/. Loading of quin2 in the absence of extracellular calcium lowered (Ca/sup 2 +/)/sub i/ from 143 nM to 31 nM. Lowering (Ca/sup 2 +/)/sub i/ inhibited TPA- or terbutaline-induced secretion by 22% and 40% respectively. These results indicate that (Ca/sup 2 +/)/sub i/ effects cAMp-induced secretion more than protein kinase C-mediated secretion in alveolar type II cells.

  16. Fine-Tuning of β-Substitution to Modulate the Lowest Triplet Excited States: A Bioinspired Approach to Design Phosphorescent Metalloporphyrinoids.

    Science.gov (United States)

    Ke, Xian-Sheng; Zhao, Hongmei; Zou, Xiaoran; Ning, Yingying; Cheng, Xin; Su, Hongmei; Zhang, Jun-Long

    2015-08-26

    Learning nature's approach to modulate photophysical properties of NIR porphyrinoids by fine-tuning β-substituents including the number and position, in a manner similar to naturally occurring chlorophylls, has the potential to circumvent the disadvantages of traditional "extended π-conjugation" strategy such as stability, molecular size, solubility, and undesirable π-π stacking. Here we show that such subtle structural changes in Pt(II) or Pd(II) cis/trans-porphodilactones (termed by cis/trans-Pt/Pd) influence photophysical properties of the lowest triplet excited states including phosphorescence, Stokes shifts, and even photosensitization ability in triplet-triplet annihilation reactions with rubrene. Prominently, the overall upconversion capability (η, η = ε·Φ(UC)) of Pd or Pt trans-complex is 10(4) times higher than that of cis-analogue. Nanosecond time-resolved infrared (TR-IR) spectroscopy experiments showed larger frequency shift of ν(C═O) bands (ca. 10 cm(-1)) of cis-complexes than those of trans-complexes in the triplet excited states. These spectral features, combining with TD-DFT calculations, suggest the strong electronic coupling between the lactone moieties and the main porphyrin chromophores and thus the importance of precisely positioning β-substituents by mimicking chlorophylls, as an alternative to "extended π-conjugation", in designing NIR active porphyrinoids. PMID:26247480

  17. Epileptogenesis causes an N-methyl-d-aspartate receptor/Ca2+-dependent decrease in Ca2+/calmodulin-dependent protein kinase II activity in a hippocampal neuronal culture model of spontaneous recurrent epileptiform discharges

    OpenAIRE

    Blair, Robert E.; Sombati, Sompong; Churn, Severn B.; DeLorenzo, Robert J.

    2008-01-01

    Alterations in the function of Ca2+/calmodulin-dependent protein kinase II (CaM Kinase II) have been observed in both in vivo and in vitro models of epileptogenesis; however the molecular mechanism mediating the effects of epileptogenesis on CaM Kinase II have not been elucidated. This study was initiated to evaluate the molecular pathways involved in causing the long lasting decrease in CaM Kinase II activity in the hippocampal neuronal culture model of low Mg2+ induced spontaneous recurrent...

  18. Regulation of voltage-gated Ca(2+) currents by Ca(2+)/calmodulin-dependent protein kinase II in resting sensory neurons.

    Science.gov (United States)

    Kostic, Sandra; Pan, Bin; Guo, Yuan; Yu, Hongwei; Sapunar, Damir; Kwok, Wai-Meng; Hudmon, Andy; Wu, Hsiang-En; Hogan, Quinn H

    2014-09-01

    Calcium/calmodulin-dependent protein kinase II (CaMKII) is recognized as a key element in encoding depolarization activity of excitable cells into facilitated voltage-gated Ca(2+) channel (VGCC) function. Less is known about the participation of CaMKII in regulating VGCCs in resting cells. We examined constitutive CaMKII control of Ca(2+) currents in peripheral sensory neurons acutely isolated from dorsal root ganglia (DRGs) of adult rats. The small molecule CaMKII inhibitor KN-93 (1.0μM) reduced depolarization-induced ICa by 16-30% in excess of the effects produced by the inactive homolog KN-92. The specificity of CaMKII inhibition on VGCC function was shown by the efficacy of the selective CaMKII blocking peptide autocamtide-2-related inhibitory peptide in a membrane-permeable myristoylated form, which also reduced VGCC current in resting neurons. Loss of VGCC currents is primarily due to reduced N-type current, as application of mAIP selectively reduced N-type current by approximately 30%, and prior N-type current inhibition eliminated the effect of mAIP on VGCCs, while prior block of L-type channels did not reduce the effect of mAIP on total ICa. T-type currents were not affected by mAIP in resting DRG neurons. Transduction of sensory neurons in vivo by DRG injection of an adeno-associated virus expressing AIP also resulted in a loss of N-type currents. Together, these findings reveal a novel molecular adaptation whereby sensory neurons retain CaMKII support of VGCCs despite remaining quiescent. PMID:25064143

  19. Regulation of Voltage-Gated Ca2+ Currents by Ca2+/Calmodulin-dependent Protein Kinase II in Resting Sensory Neurons

    Science.gov (United States)

    Kostic, Sandra; Pan, Bin; Guo, Yuan; Yu, Hongwei; Sapunar, Damir; Kwok, Wai-Meng; Hudmon, Andy; Wu, Hsiang-En; Hogan, Quinn H.

    2014-01-01

    Calcium/calmodulin-dependent protein kinase II (CaMKII) is recognized as a key element in encoding depolarization activity of excitable cells into facilitated voltage-gated Ca2+ channel (VGCC) function. Less is known about the participation of CaMKII in regulating VGCCs in resting cells. We examined constitutive CaMKII control of Ca2+ currents in peripheral sensory neurons acutely isolated from dorsal root ganglia (DRGs) of adult rats. The small molecule CaMKII inhibitor KN-93 (1.0μM) reduced depolarization-induced ICa by 16 – 30% in excess of the effects produced by the inactive homolog KN-92. The specificity of CaMKII inhibition on VGCC function was shown by efficacy of the selective CaMKII blocking peptide autocamtide-2-related inhibitory peptide in a membrane-permeable myristoylated form, which also reduced VGCC current in resting neurons. Loss of VGCC currents is primarily due to reduced N-type current, as application of mAIP selectively reduced N-type current by approximately 30%, and prior N-type current inhibition eliminated the effect of mAIP on VGCCs, while prior block of L-type channels did not reduce the effect of mAIP on total ICa. T-type currents were not affected by mAIP in resting DRG neurons. Transduction of sensory neurons in vivo by DRG injection of an adeno-associated virus expressing AIP also resulted in a loss of N-type currents. Together, these findings reveal a novel molecular adaptation whereby sensory neurons retain CaMKII support of VGCCs despite remaining quiescent. PMID:25064143

  20. Relation between the Sunrise photospheric magnetic field and the Ca II H bright features

    Science.gov (United States)

    Jafarzadeh, Shahin; Hirzberger, J.; Feller, A.; Lagg, A.; Solanki, S. K.; Pietarila, A.; Danilovic, S.; Riethmueller, T.; Barthol, P.; Berkefeld, T.; Gandorfer, A.; Knülker, M.; Martínez Pillet, V.; Schmidt, W.; Schüssler, M.; Title, A.

    Recent observations from the Sunrise balloon-borne solar telescope have enabled us to reach an unprecedented high spatial resolution on the solar surface with the near-ultraviolet photo-spheric and chromospheric images as well as the magnetograms. We use these high resolution observations to investigate the structure of the solar upper photosphere and lower chromosphere as well as their temporal evolutions. We study the relation between the inter-granular Ca II 397 nm bright structures in images obtained by the Sunrise Filter Imager (SuFI) and their corresponding photospheric vector magnetic field computed from the Imaging Magnetogram eXperiment (IMaX) observations. The targets under study are in a quiet Sun region and close to disc-centre.

  1. The Hanle and Zeeman polarization signals of the solar Ca II 8542 \\AA\\ line

    CERN Document Server

    Štěpán, Jiří

    2016-01-01

    We highlight the main results of a three-dimensional (3D) multilevel radiative transfer investigation about the solar disk-center polarization of the Ca {\\sc ii} 8542 \\AA\\ line. First, we investigate the linear polarization due to the atomic level polarization produced by the absorption and scattering of anisotropic radiation in a 3D model of the solar atmosphere, taking into account the symmetry breaking effects caused by its thermal, dynamic and magnetic structure. Second, we study the contribution of the Zeeman effect to the linear and circular polarization. Finally, we show examples of the Stokes profiles produced by the joint action of atomic level polarization and the Hanle and Zeeman effects. We find that the Zeeman effect tends to dominate the linear polarization signals only in the localized patches of opposite magnetic polarity where the magnetic field is relatively strong and slightly inclined, while outside such very localized patches the linear polarization is often dominated by the contribution ...

  2. Chromospheric Sunspot Oscillations in H-alpha and Ca II 8542A

    CERN Document Server

    Maurya, Ram Ajor; Park, Hyungmin; Yang, Heesu; Song, Donguk; Cho, Kyuhyoun

    2013-01-01

    We study chromospheric oscillations including umbral flashes and running penumbral waves in a sunspot of active region (AR) using scanning spectroscopy in H-alpha and Ca II 8542A, with the Fast Imaging Solar Spectrograph (FISS) at the 1.6 meter New Solar Telescope at Big Bear Solar Observatory. A bisector method is applied to spectral observations to construct chromospheric Doppler velocity maps. Temporal sequence analysis of these shows enhanced high-frequency oscillations inside the sunspot umbra in both lines. Their peak frequency gradually decreases outward from the umbra. The oscillation power is found to be associated with magnetic-field strength and inclination, with different relationships in different frequency bands.

  3. Simulations of the Mg II k and Ca II 8542 lines from an Alfv\\'en Wave-heated flare chromosphere

    CERN Document Server

    Kerr, Graham S; Russell, Alexander J B; Allred, Joel C

    2016-01-01

    We use radiation hydrodynamic simulations to examine two models of solar flare chromospheric heating: Alfv\\'en wave dissipation and electron beam collisional losses. Both mechanisms are capable of strong chromospheric heating, and we show that the distinctive atmospheric evolution in the mid-to-upper chromosphere results in Mg II k-line emission that should be observably different between wave-heated and beam-heated simulations. We also present Ca II 8542A profiles which are formed slightly deeper in the chromosphere. The Mg II k-line profiles from our wave-heated simulation are quite different from those from a beam-heated model and are more consistent with IRIS observations. The predicted differences between the Ca II 8542A in the two models are small. We conclude that careful observational and theoretical study of lines formed in the mid-to-upper chromosphere holds genuine promise for distinguishing between competing models for chromospheric heating in flares.

  4. The Hanle and Zeeman Polarization Signals of the Solar Ca II 8542 Å Line

    Science.gov (United States)

    Štěpán, Jiří; Trujillo Bueno, Javier

    2016-07-01

    We highlight the main results of a three-dimensional (3D) multilevel radiative transfer investigation about the solar disk-center polarization of the Ca ii 8542 Å line. First, through the use of a 3D model of the solar atmosphere, we investigate the linear polarization that occurs due to the atomic level polarization produced by the absorption and scattering of anisotropic radiation, taking into account the symmetry-breaking effects caused by its thermal, dynamic, and magnetic structure. Second, we study the contribution of the Zeeman effect to the linear and circular polarization. Finally, we show examples of the Stokes profiles produced by the joint action of the atomic level polarization and the Hanle and Zeeman effects. We find that the Zeeman effect tends to dominate the linear polarization signals only in the localized patches of opposite magnetic polarity, where the magnetic field is relatively strong and slightly inclined; outside such very localized patches, the linear polarization is often dominated by the contribution of atomic level polarization. We demonstrate that a correct modeling of this last contribution requires taking into account the symmetry-breaking effects caused by the thermal, dynamic, and magnetic structure of the solar atmosphere, and that in the 3D model used the Hanle effect in forward-scattering geometry (disk-center observation) mainly reduces the polarization corresponding to the zero-field case. We emphasize that, in general, a reliable modeling of the linear polarization in the Ca ii 8542 Å line requires taking into account the joint action of atomic level polarization and the Hanle and Zeeman effects.

  5. SYNTHESIS, CHARACTERIZATION AND ANTITUMOR ACTIVITY OF A Ca (II COORDINATION POLYMER BASED ON 3-AMINO-2-PYRAZINECARBOXYLIC ACID

    Directory of Open Access Journals (Sweden)

    XI-SHI TAI

    2015-10-01

    Full Text Available A new Ca(II coordination polymer has been obtained by reaction of Ca(ClO42·H2O with 3-amino-2-pyrazinecarboxylic acid in CH3CH2OH/H2O. It was characterized by IR, 1HNMR, thermal analysis and X-ray single crystal diffraction analysis. X-ray analysis reveals that each Ca(II center is seven-coordination with a N2O5 distorted pentagonal bipyramidal coordination environment. The Ca(II ions are linked through the O atoms of 3-amino-2-pyrazinecarboxylic acid ligands to form 1D chain structure. And then a 3D network structure is constructed by hydrogen bonds and π-π stacking. The antitumor activity of 3-amino-2-pyrazinecarboxylic acid ligand and its Ca(II coordination polymer against human intestinal adenocarcinoma HCT-8 cells, lung adenocarcinoma HCT-116 cells and human lung adenocarcinoma A549 cells line have been investigated.

  6. Epileptogenesis causes an N-methyl-d-aspartate receptor/Ca2+-dependent decrease in Ca2+/calmodulin-dependent protein kinase II activity in a hippocampal neuronal culture model of spontaneous recurrent epileptiform discharges.

    Science.gov (United States)

    Blair, Robert E; Sombati, Sompong; Churn, Severn B; Delorenzo, Robert J

    2008-06-24

    Alterations in the function of Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) have been observed in both in vivo and in vitro models of epileptogenesis; however the molecular mechanism mediating the effects of epileptogenesis on CaM kinase II has not been elucidated. This study was initiated to evaluate the molecular pathways involved in causing the long-lasting decrease in CaM kinase II activity in the hippocampal neuronal culture model of low Mg2+-induced spontaneous recurrent epileptiform discharges (SREDs). We show here that the decrease in CaM kinase II activity associated with SREDs in hippocampal cultures involves a Ca2+/N-methyl-d-aspartate (NMDA) receptor-dependent mechanism. Low Mg2+-induced SREDs result in a significant decrease in Ca2+/calmodulin-dependent substrate phosphorylation of the synthetic peptide autocamtide-2. Reduction of extracellular Ca2+ levels (0.2 mM in treatment solution) or the addition of dl-2-amino-5-phosphonovaleric acid (APV) 25 microM blocked the low Mg2+-induced decrease in CaM kinase II-dependent substrate phosphorylation. Antagonists of the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)/kainic acid receptor or L-type voltage sensitive Ca2+ channel had no effect on the low Mg2+-induced decrease in CaM kinase II-dependent substrate phosphorylation. The results of this study demonstrate that the decrease in CaM kinase II activity associated with this model of epileptogenesis involves a selective Ca2+/NMDA receptor-dependent mechanism and may contribute to the production and maintenance of SREDs in this model. PMID:18495112

  7. Experiments TGV I (double-beta decay of 48Ca) and TGV II (double-beta decay of 106Cd and 48Ca)

    International Nuclear Information System (INIS)

    Present status of experiments TGV I and TGV II is given. The TGV I collaboration has studied the double-beta decay of 48Ca with a low-background and high sensitivity Ge multi-detector spectrometer TGV (Telescope Germanium Vertical). The preliminary results of T1/22νββ = (4.2 (+3.3) (-1.3)) x 1019 years and T1/20νββ > 1.5 x 1021 years (90% CL) for double-beta decay of 48Ca has been found after the processing of experimental data obtained after 8700 hours of measuring time using approximately 1 gram of 48Ca. The aim of the experiment TGV II is the development of the experimental methods, construction of spectrometers and measurement of the ββ decay (β+β+, β+ /EC, EC/EC) of 106Cd particularly the 2νEC/EC mode. The theoretical description and performance of the TGV II spectrometer are also given. (author)

  8. Probing triplet-triplet annihilation zone and determining triplet exciton diffusion length by using delayed electroluminescence

    Science.gov (United States)

    Luo, Yichun; Aziz, Hany

    2010-05-01

    The literature shows that triplet-triplet annihilation (TTA) can provide a substantial contribution to the electroluminescence (EL) of fluorescent organic light-emitting devices (OLEDs). In this study, we utilized delayed EL measurements to probe the TTA emission zone of archetypical 8-hydroxyquinoline aluminum (Alq3) based OLEDs. The results demonstrate that the TTA emission zone of these devices is much larger than the prompt emission zone of singlet states that are formed in the electron-hole recombination. The larger TTA emission zone is attributed to the longer diffusion length of the Alq3 triplet states (60 nm) than that of Alq3 singlet states (20 nm).

  9. Retinopathy of Prematurity in Triplets

    Directory of Open Access Journals (Sweden)

    Mehmet Ali Şekeroğlu

    2016-06-01

    Full Text Available Objectives: To investigate the incidence, severity and risk factors of retinopathy of prematurity (ROP in triplets. Materials and Methods: The medical records of consecutive premature triplets who had been screened for ROP in a single maternity hospital were analyzed and presence and severity of ROP; birth weight, gender, gestational age of the infant; route of delivery and the mode of conception were recorded. Results: A total of 54 triplets (40 males, 14 females who were screened for ROP between March 2010 and February 2013 were recruited for the study. All triplets were delivered by Caesarean section and 36 (66.7% were born following an assisted conception. During follow-up, seven (13% of the infants developed ROP of any stage and two (3.7% required laser photocoagulation. The mean gestational age of triplets with ROP was 27.6±1.5 (27-31 weeks whereas it was 32.0±1.5 (30-34 weeks in those without ROP (p=0.002. The mean birth weights of triplets with and without ROP were 1290.0±295.2 (970-1600 g and 1667.5±222.2 (1130-1960 g, respectively (p<0.001. The presence of ROP was not associated with gender (p=0.358 or mode of conception (p=0.674. Conclusion: ROP in triplets seems to be mainly related to low gestational age and low birth weight. Further prospective randomized studies are necessary to demonstrate risk factors of ROP in triplets and to determine if and how gemelarity plays a role in the development of ROP.

  10. Triplet State Resonance Raman Spectroscopy

    DEFF Research Database (Denmark)

    Wilbrandt, Robert Walter; Jensen, N. H.; Pagsberg, Palle Bjørn;

    1978-01-01

    Makes the first report on the resonance Raman spectrum of a molecule in its triplet state generated by pulse radiolysis. A solution of 0.01 mol dm-3 of p-terphenyl in benzene was studied......Makes the first report on the resonance Raman spectrum of a molecule in its triplet state generated by pulse radiolysis. A solution of 0.01 mol dm-3 of p-terphenyl in benzene was studied...

  11. Role of some selected intermediate states of Ca I in the collisional excitation of 4p 2P states of Ca II in a laser-pumped Ca vapour

    International Nuclear Information System (INIS)

    The role of some intermediate states, e.g. 4s5p 3P, 3d4p (1D, 3F) of Ca I in the collisional excitation of the 4p2P3/2.1/2 states of Ca II (located at 74 720.35 and 74 497.46 cm-1 above the ground state of Ca I) following pulsed-laser pumping of the 4s4p 3PI state of Ca I (Eex = 15 210.063 cm-1), is investigated. A 'pump' and 'probe' technique is employed together with the study of fluorescent emission. The 'probe' laser selectively prepares a substantially higher population of a specific intermediate state in Ca I and the increase in the fluorescent intensity of the 4p 2P3/2-4s 2S1/2 transition of Ca II is read as the relative strength of the particular collision channel utilizing that intermediate state. It is found that the 3d4p 1D2 state has the strongest influence. (author)

  12. Triplets pass their pressure test

    CERN Multimedia

    2007-01-01

    All the LHC inner triplets have now been repaired and are in position. The first ones have passed their pressure tests with flying colours. The repaired inner triplet at LHC Point 1, right side (1R). Ranko Ostojic (on the right), who headed the team responsible for repairing the triplets, shows the magnet to Robert Zimmer, President of the University of Chicago and of Fermi Research Alliance, who visited CERN on 20th August.Three cheers for the triplets! All the LHC inner triplets have now been repaired and are in position in the tunnel. Thanks to the mobilisation of a multidisciplinary team from CERN and Fermilab, assisted by the KEK Laboratory and the Lawrence Berkeley National Laboratory (LBNL), a solution has been found, tested, validated and applied. At the end of March this year, one of the inner triplets at Point 5 failed to withstand a pressure test. A fault was identified in the supports of two out of the three quadruple magne...

  13. Thyroid hormone downregulates the expression and function of sarcoplasmic reticulum-associated CaM kinase II in the rabbit heart.

    Science.gov (United States)

    Jiang, Mao; Xu, Ande; Narayanan, Njanoor

    2006-09-01

    Phosphorylation of sarcoplasmic reticulum (SR) Ca2+-cycling proteins by a membrane-associated Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) is a well-documented physiological mechanism for regulation of transmembrane Ca2+ fluxes and the cardiomyocyte contraction-relaxation cycle. The present study investigated the effects of L-thyroxine-induced hyperthyroidism on protein expression of SR CaM kinase II and its substrates, endogenous CaM kinase II-mediated SR protein phosphorylation, and SR Ca2+ pump function in the rabbit heart. Membrane vesicles enriched in junctional SR (JSR) or longitudinal SR (LSR) isolated from euthyroid and hyperthyroid rabbit hearts were utilized. Endogenous CaM kinase II-mediated phosphorylation of ryanodine receptor-Ca2+ release channel (RyR-CRC), Ca2+-ATPase, and phospholamban (PLN) was significantly lower (30-70%) in JSR and LSR vesicles from hyperthyroid than from euthyroid rabbit heart. Western immunoblotting analysis revealed significantly higher (approximately 40%) levels of sarco(endo)plasmic reticulum Ca2+-ATPase isoform 2 (SERCA2) in JSR, but not in LSR, from hyperthyroid than from euthyroid rabbit heart. Maximal velocity of Ca2+ uptake was significantly increased in JSR (130%) and LSR (50%) from hyperthyroid compared with euthyroid rabbit hearts. Apparent affinity of the Ca2+-ATPase for Ca2+ did not differ between the two groups. Protein levels of PLN and CaM kinase II were significantly lower (30-40%) in JSR, LSR, and ventricular tissue homogenates from hyperthyroid rabbit heart. These findings demonstrate selective downregulation of expression and function of CaM kinase II in hyperthyroid rabbit heart in the face of upregulated expression and function of SERCA2 predominantly in the JSR compartment. PMID:16617128

  14. Synthesis, spectroscopic and thermal studies of Mg(II), Ca(II), Sr(II) and Ba(II) diclofenac sodium complexes as anti-inflammatory drug and their protective effects on renal functions impairment and oxidative stress

    Science.gov (United States)

    El-Megharbel, Samy M.; Hamza, Reham Z.; Refat, Moamen S.

    2015-01-01

    The main task of our present study is the preparation of newly complexes of Mg(II), Ca(II), Sr(II) and Ba(II) with diclofenac which succeeded to great extent in alleviating the side effects of diclofenac alone and ameliorating the kidney function parameters and antioxidant capacities with respect to diclofenac treated group alone. The Mg(II), Ca(II), Sr(II) and Ba(II) with diclofenac have been synthesized and characterized using infrared, electronic and 1H NMR spectral, thermogravimetric and conductivity measurements. The diclofenac ligand has been found to act as bidentate chelating agent. Diclofenac complexes coordinate through the oxygen's of the carboxyl group. The molar ratio chelation is 1:2 (M2+-dic) with general formula [M(dic)2(H2O)2]ṡnH2O. Antibacterial screening of the alkaline earth metal complexes against Escherichia coli (Gram - ve), Bacillus subtilis (Gram + ve) and anti-fungal (Asperagillus oryzae, Asperagillus niger, Asperagillus flavus) were investigated. The kidney functions in male albino rats were ameliorated upon treatment with metal complexes of dic, which are represented by decreasing the levels of urea and uric acid to be located within normal values. The other looks bright spot in this article is the assessment of antioxidant defense system including SOD, CAT and MDA with the help of Sr2+, Mg2+ and Ca2+-dic complexes. The hormones related to kidney functions and stresses have been greatly ameliorated in groups treated with dic complexes in comparable with dic treated group.

  15. [Investigation of the microstructure of biological systems by triplet label].

    Science.gov (United States)

    Kotel'niko, A I; Kuznetsov, S N; Fogel', V R; Likhtenshteĭn, G I

    1979-01-01

    A method for investigating the microstruct and dynamics of biological systems by means of triplet-excited molecules is suggested. The method is based on the phenomenon of triplet excitation disactivation by exchange-resonance triplet-triplet energy transfer to the acceptor or by intercombination conversion induced by interaction of an excited molecule with a paramagnetic center. The disactivation efficiency was measured by registrating the phosphorescense decay kinetics. The interaction of the triplet label eosin isothiocyanate, covalently coupled with albumine, lysozyme, sarcoplasmic reticulum membrane and Ca-Mg-dependent sarcoplasmic reticulum ATPase, with O2, the stable nitroxide radicals and ions of Mn2+ was investigated to analyse the potentialities of this method. As a model system the eosin phosphorescence quenching by the same quenchers in glycerine-aguaous solutions was studied. The method permits to investigate the microviscosity and microstructure of biological objects in the label attached region on interaction of the label with a sound-quencher with constants being 10(4) divided by 10(9) M-1 sec-1 and to measure the lateral diffusion of molecules in highly viscosity media (10 divided by 10(5) santypuas). PMID:223037

  16. Fetomaternal outcome in triplet pregnancy

    International Nuclear Information System (INIS)

    To determine maternal outcome as antenatal and postnatal complications and neonatal outcome as birth weight, morbidity and mortality in triplet gestation. All the patients with triplet pregnancy beyond 28 weeks gestation, who delivered at the study place during above period were included in the study. The primary outcome measures were frequency of maternal complications and neonatal birth, weight and morbidity. Secondary outcome measures included the frequency of assisted conception in the studied cohart. Eighteen women had triplet pregnancy beyond 28 weeks. Nine were booked, 6 non-booked and 3 of them were referred. Mean duration of gestation was 237.8 days (33.8 weeks). The antenatal complications were preterm delivery in 50%, hypertension in 50%, anemia in 44.4% and obstetric cholestasis in 5.6%. Eight patients (44.4%) suffered postpartum hemorrhage. One patient had peripartum hysterectomy and later expired in intensive care unit after three weeks. Maternal mortality ratio was 5.6%. Fifty five percent women had induction of ovulation with Clomiphene, while none had In Vitro Fertilization (IVF) or Intracytoplasmic Insemination (ICSI) or received gonadotrophins. Fifteen sets of triplets were delivered abdominally. Mean birth weights of 1st, 2nd and 3rd triplet were 1651, 1640 and 1443 grams respectively. Five sets of triplets (27.8%) had more than 25% discordance for birth weight. The mean Apgar scores of the babies at 1 and 10 minutes after birth were 6.0 and 8.0, 5.6 and 7.5; and 5.2 and 7.0 respectively. Of the 54 infants, 18 required Neonatal Intensive Care Unit (NICU) admission and 14 were admitted in nursery. Two died shortly after birth. Total perinatal mortalities were 13 including 4 cases of intra-uterine demise. Three babies suffered from jaundice, 7 had sepsis and 8 had respiratory distress syndrome. Triplet gestation had a high rate of fetomaternal complications. Majority had history of assisted conception. (author)

  17. STATISTICAL PROPERTIES OF THE DISK COUNTERPARTS OF TYPE II SPICULES FROM SIMULTANEOUS OBSERVATIONS OF RAPID BLUESHIFTED EXCURSIONS IN Ca II 8542 AND Hα

    International Nuclear Information System (INIS)

    Spicules were recently found to exist as two different types when a new class of so-called type II spicules was discovered at the solar limb with the Solar Optical Telescope on board the Hinode spacecraft. These type II spicules have been linked with on-disk observations of rapid blueshifted excursions (RBEs) in the Hα and Ca II 8542 lines. Here we analyze observations optimized for the detection of RBEs in both Hα and Ca II 8542 lines simultaneously at a high temporal cadence taken with the Crisp Imaging Spectropolarimeter at the Swedish Solar Telescope on La Palma. In this study, we used a high-quality time sequence for RBEs at different blueshifts and employed an automated detection routine to detect a large number of RBEs in order to expand on the statistics of RBEs. We find that the number of detected RBEs is strongly dependent on the associated Doppler velocity of the images on which the search is performed. Automatic detection of RBEs at lower velocities increases the estimated number of RBEs to the same order of magnitude expected from limb spicules. This shows that RBEs and type II spicules are indeed exponents of the same phenomenon. Furthermore, we provide solid evidence that Ca II 8542 RBEs are connected to Hα RBEs and are located closer to the network regions with the Hα RBEs being a continuation of the Ca II 8542 RBEs. Our results show that RBEs have an average lifetime of 83.9 s when observed in both spectral lines and that the Doppler velocities of RBEs range from 10 to 25 km s–1 in Ca II 8542 and 30 to 50 km s–1 in Hα. In addition, we automatically determine the transverse motion of a much larger sample of RBEs than previous studies, and find that, just like type II spicules, RBEs undergo significant transverse motions of the order of 5-10 km s–1. Finally, we find that the intergranular jets discovered at Big Bear Solar Observatory are a subset of RBEs.

  18. ADSORPTION OF Ca(II FROM AQUEOUS SOLUTION ONTO CELLULOSIC FIBERS AND ITS IMPACT ON THE PAPERMAKING PROCESS

    Directory of Open Access Journals (Sweden)

    Guangxiang Yuan

    2011-06-01

    Full Text Available Calcium(II is one of the most common metal ions in papermaking systems. However, the effect of Ca2+ on papermaking processes has not drawn much attention. The adsorption of Ca2+ from aqueous solutions onto bleached Eucalyptus globulus kraft pulp fibers was investigated. Thermodynamic results indicate that the adsorption of Ca2+ onto bleached E. globulus kraft pulp fibers was exothermic, reversible, and spontaneous. The equilibrium data followed Langmuir isotherms. The adsorption basically agrees with the ionic reaction model between carboxyl groups of fibers and Ca2+ in which the molar ratio of carboxyl to Ca2+ is close to 2:1. The binding capacity with carboxyl groups is so strong that the anionic charge of the adsorption sites in fibers can be screened, leading to decreased performance of cationic polyacrylamide for retention and drainage, Alkyl Ketene Dimer (AKD for sizing, and cationic starch for dry strength. The precipitation effect of Ca2+ with three kinds of dissolved and colloidal substances (sodium rosinate, sodium stearate, sodium oxalate also was investigated. The results showed that deposits formed by Ca2+ and dissolved and colloidal substances, which could adsorb to the surfaces of fibers, would affect drainage and retention abilities of cationic polyacrylamide.

  19. Observational Searches for Chromospheric -Mode Oscillations from CaII H-Line Observations

    Indian Academy of Sciences (India)

    R. Kariyappa; L. Damé; K. M. Hiremath

    2006-06-01

    We have used a high spatial and temporal resolution of long time sequence of spectra in CaII H-line obtained at the Vacuum Tower Telescope (VTT) of the Sacramento Peak Observatory on a quiet region at the center of the solar disk over a large number of bright points and network elements to search for atmospheric (chromospheric) -mode oscillations. An important parameter of the H-line profile, intensity at H2V(IH2V), has been derived from a large number of line profiles. We derived the light curves of all the bright points and network elements. The light curves represent the main pulse with large intensity amplitude and followed by several follower pulses with lower intensity amplitudes. The light curves of these bright points would give an impression that one can as well draw curves towards and away from the highest peak (main pulse) showing an exponential growth and decay of the amplitudes. An exponential decaying function has been fitted for all the light curves of the bright points to determine the damping time of the modes that are more or less the same, and one value of the coefficient of exponent can represent reasonably well the decay for all the cases. The FFT analysis of temporal variation of both the bright points and the network elements indicates around 10-min periodicity. We speculate that this longer period of oscillation may be related to chromospheric -mode oscillations.

  20. Oscillations of the Sun's chromosphere. VIII. Horizontal motions of CA II K bright points

    Science.gov (United States)

    Wellstein, S.; Kneer, F.; von Uexkuell, M.

    1998-07-01

    We present a re-analysis of a time series of solar disc centre Ca ii K2v filtergrams taken with the Vacuum Tower Telescope at the Observatorio del Teide/Tenerife. We concentrate on the measurements of proper motions of K grains in the internetwork regions and of bright points in the chromospheric network. For the K grains we find horizontal velocities of 2-15 km s(-1) , values much lower than those deduced by Steffens et al. (1996) from a smaller sample, analyzed differently. In accord with our earlier conclusion from k-omega diagrams (Kneer & von Uexkuell 1993) and with numerical simulations by Carlsson & Stein (1997) high-frequency (pseudo-) p-modes can viably explain the K grains. Yet, the rareness of the K grains may indicate a connection to magnetic fields. The proper motions of the network bright points are non-periodic, very impulsive, with velocities of 7-10 km s(-1) . Estimating the energy flux if these motions are magnetic kink waves (cf. Choudhuri et al. 1993, Muller et al. 1994), we find it sufficient to heat the solar corona, but too small to cover the radiative losses of the chromospheric network.

  1. The Appearance of Spicules in High Resolution Observations of Ca II H and H-alpha

    CERN Document Server

    Pereira, Tiago M D; Carlsson, Mats

    2016-01-01

    Solar spicules are chromospheric fibrils that appear everywhere on the Sun, yet their origin is not understood. Using high resolution observations of spicules obtained with the Swedish 1-m Solar Telescope we aim to understand how spicules appear in filtergrams and Dopplergrams, how they compare in Ca II H and H-alpha, and what can make them appear and disappear. We find spicules display a rich and detailed spatial structure, and show a distribution of transverse velocities that when aligned with the line of sight can make them appear at different H-alpha wing positions. They become more abundant at positions closer to the line core, reflecting a distribution of Doppler shifts and widths. In H-alpha width maps they stand out as bright features both on disk and off-limb, reflecting their large Doppler motions and possibly higher temperatures than in the typical H-alpha formation region. Spicule lifetimes measured from narrowband images at only a few positions will be an underestimate because Doppler shifts can ...

  2. SUGRA interactions within flavor triplets

    CERN Document Server

    Towe, J

    2005-01-01

    A specific new quark permits that flavor generations constitute a representation of the 3-dimensional SU(3) symmetry that characterizes the Z(3) orbifold. In this context, color and supergravity bind triplets and 4-tuplets into composite fields of spin 3/2 and spin 2; and the symmetry E(8) that characterizes (the observable sector of) 10-spacetime is interpreted as having reduced to SU(5)XSU(3), where SU(3) refers to the 3-dimensional symmetry described above and SU(5) consists of colors and of isotopic spin classes that are devoid of color and hypercharge. In this context, supergravity interactions occur to color bound quarks that are experiencing asymptotic freedom within triplets. Quark-lepton transitions are produced, but quickly reverse, preserving the triplets. The symmetry consisting of six quark classes and six lepton classes is also maintained because the predicted quark is an anomalous, left-handed version of the strange quark.

  3. Ca(II, Zn(II and Au(III sulfamethoxazole sulfa-drug complexes: Synthesis, spectroscopic and anticancer evaluation studies

    Directory of Open Access Journals (Sweden)

    Fatima A.I. Al-Khodir

    2015-09-01

    Full Text Available Herein in this article, three new Ca(II, Zn(II and Au(III complexes of sulfamethoxazole (SZ (sulfa-drug have been synthesized for the first time. The sulfa-drugs have a great attentions because of their therapeutic applications against bacterial infections. The SZ complexes were discussed with the help of elemental analyses, molar conductance and spectroscopic instruments e.g. IR, 1H-NMR, and electronic spectra. Investigations of the infrared spectra of the SZ and their metal complexes indicated the vibrations due to the sulfonamido (SO2 and –NH and isoxazole (C=N groups are shifted with respect to the free molecule in line with their coordination to the metal. In case of calcium(II an zinc(II complexes, the coordination site of SZ are the sulfonyl oxygen and SO2-NH sulfonamide nitrogen, but in gold(III complex, the gold metal ions coordinates through the sulfonyl oxygen and isoxazole nitrogen. These complexes are formulated as: [Ca(SZ(Cl2].8H2O (1, [Zn(SZ(Cl2].2H2O (2 and [Au(SZ(Cl2].Cl (3. The molar conductance data reveals that both Ca(II and Zn(II complexes are non-electrolyte but gold(III complex is electrolyte. The morphological nano structures of SZ complexes were checked using X-ray powder diffraction (XRD, scanning electron microscope (SEM and transmission electron microscopy (TEM. The gold(III complex was recorded good anticancer behavior against Human colon carcinoma (HCT-116 cells and human hepatocellular carcinoma (HepG-2 cells.

  4. Ca II 854.2 nm Spectromagnetograms: A Powerful Chromospheric Diagnostic

    Science.gov (United States)

    Harvey, J. W.; Bertello, Luca; Branston, D.; Britanik, J.; Bulau, S.; Cole, L.; Gosain, Sanjay; Harker, Brian; Jones, Harrison P.; Marble, A.; Martinez Pillet, V.; Pevtsov, A.; Schramm, K.; Streander, Kim; Villegas, H.

    2016-05-01

    The transition from physical dominance by plasma flows in the photosphere to magnetic pressure in the solar chromosphere motivates as many diagnostic observations as possible across this important region. Among the few ground-accessible spectral lines formed within the chromosphere, the Ca II 854.2 nm line has the desirable properties of presence everywhere on the solar disk, Zeeman sensitivity, and narrow line width. Mapped observations of circular polarization within this line (spectromagnetograms) have been made at NSO infrequently since 1974, with regular daily full-disk observations starting in August 1996. Full-disk spectral observations of the complete Stokes polarization vector are now being made regularly since November 2015. It is not easy to estimate chromospheric magnetic field properties from the 854.2 nm line profile polarization. To provide rough quick-look vector field maps we found that the weak-field approximation provides a fair first estimate of the line-of-sight component but appears to be too simple to interpret the transverse magnetic field from frequently asymmetric, linearly-polarized line profiles. More realistic estimates of the chromospheric vector field, short of extremely lengthy, full 3D, non-local radiative transfer inversions, are being investigated. We briefly introduce recent instrumental modifications and observational characteristics, sample observations, and results concerning the expansion of the chromospheric field with increasing height, the presence of large areas of weak, nearly horizontal fields, and field estimates in plages, sunspots, flares, filaments, and filament channels. The Stokes spectra will be freely available to the community.This work utilizes SOLIS data obtained by the NSO Integrated Synoptic Program (NISP), managed by the National Solar Observatory, which is operated by the Association of Universities for Research in Astronomy (AURA), Inc. under a cooperative agreement with the National Science Foundation.

  5. Physicochemical impact studies of gamma rays on "aspirin" analgesics drug and its metal complexes in solid form: Synthesis, spectroscopic and biological assessment of Ca(II), Mg(II), Sr(II) and Ba(II) aspirinate complexes

    Science.gov (United States)

    Refat, Moamen S.; Sharshar, T.; Elsabawy, Khaled M.; Heiba, Zein K.

    2013-09-01

    Metal aspirinate complexes, M2(Asp)4, where M is Mg(II), Ca(II), Sr(II) or Ba(II) are formed by refluxed of aspirin (Asp) with divalent non-transition metal ions of group (II) and characterized by elemental analysis and spectroscopic measurements (infrared, electronic, 1H NMR, Raman, X-ray powder diffraction and scanning electron microscopy). Elemental analysis of the chelates suggests the stoichiometry is 1:2 (metal:ligand). Infrared spectra of the complexes agree with the coordination to the central metal atom through three donation sites of two oxygen atoms of bridge bidentate carboxylate group and oxygen atom of sbnd Cdbnd O of acetyl group. Infrared spectra coupled with the results of elemental analyzes suggested a distorted octahedral structure for the M(II) aspirinate complexes. Gamma irradiation was tested as a method for stabilization of aspirin as well as their complexes. The effect of gamma irradiation, with dose of 80 Gy, on the properties of aspirinate complexes was studied. The aspirinate chelates have been screened for their in vitro antibacterial activity against four bacteria, gram-positive (Bacillus subtilis and Staphylococcus aureus) and gram-negative (Escherichia coli and Pseudomonas aeruginosa) and two strains of fungus (Aspergillus flavus and Candida albicans). The metal chelates were shown to possess more antibacterial activity than the free aspirin chelate.

  6. The chromospheric Ca II and Mg II radiative losses in late-type stars: a computational comparison between two-level and multi-level atomic models

    Science.gov (United States)

    Fawzy, Diaa E.

    2015-06-01

    In the current study we present radiation correction factors to compute the radiative losses by Mg II and Ca II ions during the process of constructing theoretical models for the chromospheres in late-type stars (spectral type in the range F5V-K8V). We combine the two-level atom approach with the multi-level atom method to accurately compute the radiation correction factors. The procedure is fast and reasonably accurate to be implemented in the time-dependent computations. In the current computations we implement what is called pseudo-partial frequency redistribution and the time-dependent ionization in regard to hydrogen. The radiative correction factors for Mg II show very slight variation for the different spectral types with average value of 1.5. The values we obtained for Ca II show very strong dependence on spectral types and the basic parameters, with values range between 5.58 to 4.22 for F5V and K8V spectral types, respectively. The obtained results accelerate the process of constructing theoretical model chromospheres based on mechanical heating by monochromatic and wave spectra. The current study is an initial step in establishing hybrid multi-dimensional models of stellar chromospheres.

  7. DATE PRELIMINARE PRIVIND VIABILITATEA POLENULUI CA BIOINDICATOR AL CALITĂŢII AERULUI ÎN TIMIŞOARA

    Directory of Open Access Journals (Sweden)

    Nicoleta IANOVICI

    2008-01-01

    Full Text Available Această cercetare prezintă date obţinute prin prelevarea polenului de la patru specii (Plantago lanceolata, Plantago major, Ambrosia artemisiifolia, Tilia cordata şi testarea viabilităţii acestuia prin tratare cu TTC. Aceste date preliminare sunt insuficiente pentru a da o concluzie specifică. Oricum, se poate spune că viabilitatea polenului poate fi un parametru reprezentativ pentru a stabili care plante sunt mai bine adaptate mediului urban. Modificarea viabilităţii polenului indică prezenţa gazelor cu caracter poluant, rezultate mai ales din traficul rutier, la toate cele patru specii. Polenul de Plantago lanceolata şi Tilia cordata ar putea fi folosit ca bio-indicator al calităţii aerului într-un ecosistem urban.

  8. Tough Decisions for Premature Triplets.

    Science.gov (United States)

    Hurst, Ashley; Vergales, Brooke D; Paget-Brown, Alix; Mercurio, Mark; Lantos, John D

    2016-02-01

    When infants are born at the borderline of viability, doctors and parents have to make tough decisions about whether to institute intensive care or provide only palliative care. Often, these decisions are made in moments of profound emotional turmoil, and parents receive different information from different health professionals. Communication can become garbled. It may be difficult to tell when and whether the patient's clinical condition has changed enough so that certain choices that had once been permissible become impermissible. In this "Ethics Rounds," we present a case of triplets born at the borderline of viability. We sought comments from the triplets' parents, the doctors and ethicist who were caring for the infants, and a bioethicist/neonatologist from another hospital. PMID:26738882

  9. Triplets of Quasars at high redshift I: Photometric data

    OpenAIRE

    Alonso, M. Victoria; Coldwell, Georgina V.; Sochting, Ilona; Bornancini, Carlos; Smith, Malcolm G.; Lambas, Diego Garcia; Rest, Armin

    2008-01-01

    We have conducted an optical and infrared imaging in the neighbourhoods of 4 triplets of quasars. R, z', J and Ks images were obtained with MOSAIC II and ISPI at Cerro Tololo Interamerican Observatory. Accurate relative photometry and astrometry were obtained from these images for subsequent use in deriving photometric redshifts. We analyzed the homogeneity and depth of the photometric catalog by comparing with results coming from the literature. The good agreement shows that our magnitudes a...

  10. Atorvastatin blocks increased l-type Ca2+ current and cell injury elicited by angiotensin II via inhibiting oxide stress.

    Science.gov (United States)

    Ma, Yanzhuo; Kong, Lingfeng; Qi, Shuying; Wang, Dongmei

    2016-04-01

    Thel-type Ca(2+)current (ICa,l) plays a crucial role in shaping action potential and is involved in cardiac arrhythmia. Statins have been demonstrated to contribute to anti-apoptotic and anti-arrhythmic effects in the heart. Here, we examined whether atorvastatin regulates theICa,land cell injury induced by angiotensin II (AngII) as well as the putative intracellular cascade responsible for the effects. Cultured neonatal rat ventricular myocytes were incubated with AngII for 24 h, and then cell injury and expression levels of Nox2/gp91(phox), p47(phox) ,and Cav1.2 were analyzed. In addition,ICa,lwas recorded using the whole-cell patch-clamp technique, and mechanisms of atorvastatin actions were also investigated. It was found that the number of apoptotic cardiomyocytes was increased and cell viability was significantly decreased after AngII administration. AngII also augmented the expressions of Nox2/gp91(phox)and p47(phox)compared with control cardiomyocytes. Exposure to AngII evokedICa,lin a voltage-dependent manner without affecting theI-Vrelationship. In addition, AngII enhanced membrane Cav1.2 expression. These effects were abolished in the presence of the reactive oxygen species (ROS) scavenger, manganese (III)-tetrakis 4-benzoic acid porphyrin [Mn(III)TBAP], or the 3-hydroxy-3-methylglutaryl-CoA reductase inhibitor, atorvastatin. These results suggested that atorvastatin mediates cardioprotection against arrhythmias and cell injury by controlling the AngII-ROS cascade. PMID:26940997

  11. Sorption of radiocobalt(II) onto Ca-montmorillonite. Effect of contact time, solid content, pH, ionic strength and temperature

    International Nuclear Information System (INIS)

    In this paper, the sorption of Co(II) from aqueous solution to Ca-montmorillonite was studied under ambient conditions by using batch technique. The effects of contact time, solid content, pH, ionic strength and temperature on the sorption of Co(II) to Ca-montmorillonite was also investigated. The results indicated that the sorption of Co(II) was strongly dependent on pH values. The sorption was dependent on ionic strength at low pH values, but independent of ionic strength at high pH values. Outer-sphere surface complexes were formed on the surface of Ca-montmorillonite at low pH values, whereas inner-sphere surface complexes were formed at high pH values. The Langmuir, Freundlich and Dubinin-Radushkevich (D-R) models were used to simulate the sorption isotherms of Co(II) at three different temperatures. The thermodynamic parameters (ΔH0, ΔS0 and ΔG0) were calculated from the temperature dependent sorption isotherms, and the results indicated that the sorption reaction of Co(II) to Ca-montmorillonite was an endothermic and spontaneous process. The high sorption capacity of Co(II) on Ca-montmorillonite suggests that the Ca-montmorillonite is a suitable material for the preconcentration and solidification of radiocobalt from aqueous solutions. (author)

  12. Microwave assisted synthesis of novel acridine-acetazolamide conjugates and investigation of their inhibition effects on human carbonic anhydrase isoforms hCA I, II, IV and VII.

    Science.gov (United States)

    Ulus, Ramazan; Aday, Burak; Tanç, Muhammet; Supuran, Claudiu T; Kaya, Muharrem

    2016-08-15

    4-Amino-N-(5-sulfamoyl-1,3,4-thiadiazol-2-yl)benzamide was condensed with cyclic-1,3-diketones (dimedone and cyclohexane-1,3-dione) and aromatic aldehydes under microwave irradiation, leading to a series of acridine-acetazolamide conjugates. The new compounds were investigated as inhibitors of carbonic anhydrases (CA, EC 4.2.1.1), and more precisely cytosolic isoforms hCA I, II, VII and membrane-bound one hCA IV. All investigated isoforms were inhibited in low micromolar and nanomolar range by the new compounds. hCA IV and VII were inhibited with KIs in the range of 29.7-708.8nM (hCA IV), and of 1.3-90.7nM (hCA VII). For hCA I and II the KIs were in the range of 6.7-335.2nM (hCA I) and of 0.5-55.4nM (hCA II). The structure-activity relationships (SAR) for the inhibition of these isoforms with the acridine-acetazolamide conjugates reported here were delineated. PMID:27298005

  13. Heme-induced Trypanosoma cruzi proliferation is mediated by CaM kinase II

    International Nuclear Information System (INIS)

    Trypanosoma cruzi, the etiologic agent of Chagas disease, is transmitted through triatomine vectors during their blood-meal on vertebrate hosts. These hematophagous insects usually ingest approximately 10 mM of heme bound to hemoglobin in a single meal. Blood forms of the parasite are transformed into epimastigotes in the crop which initiates a few hours after parasite ingestion. In a previous work, we investigated the role of heme in parasite cell proliferation and showed that the addition of heme significantly increased parasite proliferation in a dose-dependent manner . To investigate whether the heme effect is mediated by protein kinase signalling pathways, parasite proliferation was evaluated in the presence of several protein kinase (PK) inhibitors. We found that only KN-93, a classical inhibitor of calcium-calmodulin-dependent kinases (CaMKs), blocked heme-induced cell proliferation. KN-92, an inactive analogue of KN-93, was not able to block this effect. A T. cruzi CaMKII homologue is most likely the main enzyme involved in this process since parasite proliferation was also blocked when Myr-AIP, an inhibitory peptide for mammalian CaMKII, was included in the cell proliferation assay. Moreover, CaMK activity increased in parasite cells with the addition of heme as shown by immunological and biochemical assays. In conclusion, the present results are the first strong indications that CaMKII is involved in the heme-induced cell signalling pathway that mediates parasite proliferation.

  14. Heme-induced Trypanosoma cruzi proliferation is mediated by CaM kinase II

    Energy Technology Data Exchange (ETDEWEB)

    Souza, C.F. [Laboratorio de Imunomodulacao e Protozoologia, Instituto Oswaldo Cruz, Fiocruz (Brazil); Carneiro, A.B.; Silveira, A.B. [Laboratorio de Sinalizacao Celular, Instituto de Bioquimica Medica, UFRJ (Brazil); Laranja, G.A.T. [Laboratorio de Interacao Tripanosomatideos e Vetores, Departamento de Bioquimica, IBRAG, UERJ, 20551-030 Rio de Janeiro (Brazil); Silva-Neto, M.A.C. [Laboratorio de Sinalizacao Celular, Instituto de Bioquimica Medica, UFRJ (Brazil); INCT, Entomologia Molecular (Brazil); Costa, S.C. Goncalves da [Laboratorio de Imunomodulacao e Protozoologia, Instituto Oswaldo Cruz, Fiocruz (Brazil); Paes, M.C., E-mail: mcpaes@uerj.br [Laboratorio de Interacao Tripanosomatideos e Vetores, Departamento de Bioquimica, IBRAG, UERJ, 20551-030 Rio de Janeiro (Brazil); INCT, Entomologia Molecular (Brazil)

    2009-12-18

    Trypanosoma cruzi, the etiologic agent of Chagas disease, is transmitted through triatomine vectors during their blood-meal on vertebrate hosts. These hematophagous insects usually ingest approximately 10 mM of heme bound to hemoglobin in a single meal. Blood forms of the parasite are transformed into epimastigotes in the crop which initiates a few hours after parasite ingestion. In a previous work, we investigated the role of heme in parasite cell proliferation and showed that the addition of heme significantly increased parasite proliferation in a dose-dependent manner . To investigate whether the heme effect is mediated by protein kinase signalling pathways, parasite proliferation was evaluated in the presence of several protein kinase (PK) inhibitors. We found that only KN-93, a classical inhibitor of calcium-calmodulin-dependent kinases (CaMKs), blocked heme-induced cell proliferation. KN-92, an inactive analogue of KN-93, was not able to block this effect. A T. cruzi CaMKII homologue is most likely the main enzyme involved in this process since parasite proliferation was also blocked when Myr-AIP, an inhibitory peptide for mammalian CaMKII, was included in the cell proliferation assay. Moreover, CaMK activity increased in parasite cells with the addition of heme as shown by immunological and biochemical assays. In conclusion, the present results are the first strong indications that CaMKII is involved in the heme-induced cell signalling pathway that mediates parasite proliferation.

  15. Two-dimensional radiative transfer. II. The wings of Ca K and Mg k

    International Nuclear Information System (INIS)

    The effect of horizontal radiative transfer on the Ca K and Mg k line wing intensities in two-component models of the solar atmosphere is investigated. No significant influence on the spatially unresolved wing profiles of either line was found, even for models in which the lateral variation was extreme over distances approaching a vertical scale height. Horizonal contrast as measured by the spatially resolve Mg k profile was found to be markedly reduced by lateral transfer over scales at or below the current resolution limit. Contrast as measured in the Ca K wing was relatively unaffected and was maintained down to lateral sizes approaching a vertical scale height. The behavior of Ca K relative to Mg k is attributed to the larger amount of photon destruction by incoherent scattering in the Ca K wing, which limits the distance that photons can diffuse laterally and forces the line to be formed near LTE. We therefore conclude that the small-scale photospheric temperature structure predicted by many models can be detected in Ca K, and that efforts toward reducing seeing limitations on the resolution of solar observations should be encouraged

  16. Analysis of Ca II K images aiming to determine long-term trends in solar irradiance variability

    Science.gov (United States)

    Kar, Anuradha; Ermolli, Ilaria; Krivova, Natalie; Solanki, Sami

    2013-04-01

    The change in radiative output of the Sun on time scales longer than a day is attributed to the variability in solar surface magnetic fields. Direct irradiance measurements are only available for less than four decades. To reconstruct long term trends in solar total and spectral irradiance, proxies of solar surface magnetism like sunspot, facular and network areas are needed. Currently, sunspot records alone are used for this purpose, from which the deduction of facular and network areas is rather indirect. Historical records of full disk images of the Sun taken in the Ca II K spectral line (393.3 nm) have the potential to provide far more direct information about the distribution and evolution of faculae and network elements. The latter appear as bright regions in the Ca II K spectroheliograms and their intensity is correlated with the magnetic field strength of the features on the solar surface. Solar full disk images in the Ca II K line have been recorded since the beginning of the 20th century at a number of solar observatories such as at Arcetri (Italy), Mount Wilson(California, US) and Kodaikanal (India). The images are available in digitized archives that contain the data processed for standard instrumental calibrations. To utilize these records for irradiance studies, the next step is to identify the bright magnetic features from the images using feature recognition techniques. We test different feature identification methods which are first applied to a set of recent images from the PSPT instrument at the Osservatorio Astronomico di Roma, taken during three periods characterized by high, medium and low levels of activity. Then the performance of these methods to historical images from Arcetri, Mt. Wilson and Kodaikanal archives is tested. The results will be presented and discussed here.

  17. The wings of Ca II H and K as photospheric diagnostics and the reliability of one-dimensional photosphere modeling

    OpenAIRE

    Sheminova, V. A.

    2012-01-01

    The extended wings of the Ca II H and K lines provide excellent diagnostics of the temperature stratification of the photosphere of the Sun and of other cool stars, thanks to their LTE opacities and source functions and their large span in formation height. The aim of this study is to calibrate the usage of the H and K wings in one-dimensional interpretation of spatially averaged spectra and in deriving per-pixel stratifications from resolved spectra. I use multi-dimensional simulations of so...

  18. Competition between singlet and triplet superconductivity

    OpenAIRE

    De Cao, Tian; Wang, Tie Bang

    2009-01-01

    The competition between singlet and triplet superconductivity is examined in consideration of correlations on an extended Hubbard model. It is shown that the triplet superconductivity may not be included in the common Hubbard model since the strong correlation favors the singlet superconductivity, and thus the triplet superconductivity should be induced by the electron-phonon interaction and the ferromagnetic exchange interaction. We also present a superconducting qualification with which mag...

  19. Influence of plasma chemistry on oxygen triplets

    OpenAIRE

    Milosavljevic, Vladimir; Ellingboe, Albert; Daniels, Stephen

    2011-01-01

    The plasma chemistry of fluorocarbon-oxygen-argon discharges and its influence on prominent oxygen triplets are studied. The oxygen 777 triplet is very important for the measurement of atomic oxygen in low pressure plasmas, since the 777.417 nm spectral line is frequently used for actinometry. In this paper we identify changes in the individual 777 triplet lines arising from cascade effects from higher energy levels of oxygen, and from resonant energy transfer from energetic carbon...

  20. The Chemical Abundances of the Stellar Populations in the Leo I and Leo II dSph Galaxies

    CERN Document Server

    Bosler, T L; Stetson, P B; Bosler, Tammy L.; Smecker-Hane, Tammy A.; Stetson, Peter B.

    2006-01-01

    We have obtained spectra of 102 red giant branch (RGB) stars in the Leo I dwarf spheroidal galaxy (dSph) and 74 RGB stars in the Leo II dSph using LRIS on the Keck I 10-meter Telescope. We report on the calcium abundances [Ca/H] derived from the strengths of the Ca II triplet absorption lines at 8498, 8542, 8662 angstroms in the stellar spectra using a new Ca II triplet calibration to [Ca/H]. The two galaxies have different average [Ca/H] values of -1.34 +/- 0.02 for Leo I and -1.65 +/- 0.02 for LeoII with intrinsic abundance dispersions of 1.2 and 1.0 dex, respectively. The typical random and total errors in derived abundances are 0.10 and 0.17 dex per star. For comparison to existing literature, we also converted our Ca II measurements to [Fe/H] on the scale of Carretta and Gratton (1997) though we discuss why this may not be the best determinant of metallicity; Leo I has a mean [Fe/H] = -1.34 and Leo II has a mean [Fe/H] = -1.59. The metallicity distribution function of Leo I is approximately Gaussian in s...

  1. Magnetic Field Effects on Triplet-Triplet Annihilation in Solutions: Modulation of Visible/NIR Luminescence

    OpenAIRE

    Mani, Tomoyasu; Vinogradov, Sergei A.

    2013-01-01

    Photon upconversion based on sensitized triplet-triplet annihilation (TTA) presents interest for such areas as photovoltaics and imaging. Usually energy upconversion is observed as p-type delayed fluorescence from molecules whose triplet states are populated via energy transfer from a suitable triplet donor, followed by TTA. Magnetic field effects (MFE) on delayed fluorescence in molecular crystals are well known; however, there exist only a few examples of MFE on TTA in solutions, and all of...

  2. Charge pumping due to triplet vector chirality in ferromagnet/triplet superconductor junctions

    OpenAIRE

    Yokoyama, Takehito

    2011-01-01

    We investigate charge pumping in ferromagnet/triplet superconductor junctions where the magnetization of the ferromagnet is inhomogeneous and dynamical. It is shown that charge current is pumped due to the coupling of the localized spin with triplet vector spin chirality, vector spin chirality formed by the triplet vector of Cooper pairing. Physical mechanism of the charge pumping is also discussed.

  3. Ca II and Na I absorption in the QSO S4 0248 + 430 due to an intervening galaxy

    International Nuclear Information System (INIS)

    Observations of the QSO S4 0248 + 430 and a nearby anonymous galaxy are presented. Two absorption components are found in both Ca II H and K and Na I D1 and D2 at z(a) = 0.0515, 0.0523. Column densities of log N(Ca II) = 13.29, 13.50, and log N(Na I) = 13.79, 14.18 are found for z(a) = 0.0515, 0.0523 absorption systems, respectively. The column density ratios imply considerable calcium depletion and disk-type absorbing gas. At least one and possibly both absorption components are produced by high-velocity gas. A broadband image of the field shows an asymmetrical armlike feature or possible tidal tail covering and extending past the position of the QSO. The presence of this extended feature and the apparent difference between the absorption velocities and galaxy rotation velocity suggest that the absorbing gas is not ordinary disk gas, but rather is a result of tidal disruption. 24 refs

  4. RG-II from Panax ginseng C.A. Meyer suppresses asthmatic reaction

    Directory of Open Access Journals (Sweden)

    In Duk Jung

    2012-02-01

    Full Text Available In asthma, T helper 2 (TH2-type cytokines such as interleukin(IL-4, IL-5, and IL-13 are produced by activated CD4+ T cells.Dendritic cells played an important role in determining thefate of naïve T cells into either TH1 or TH2 cells. Wedetermined whether RG-II regulates the TH1/TH2 immuneresponse by using an ovalbumin-induced murine model ofasthma. RG-II reduced IL-4 production but increased interferon-gamma production, and inhibited GATA-3 geneexpression. RG-II also inhibited asthmatic reactions includingan increase in the number of eosinophils in bronchoalveolarlavage fluid, an increase in inflammatory cell infiltration inlung tissues, airway luminal narrowing, and airway hyperresponsiveness.This study provides evidence that RG-II plays acritical role in ameliorating the pathogenic process ofasthmatic inflammation in mice. These findings provide newinsights into the immunotherapeutic role of RG-II in terms ofits effects in a murine model of asthma. [BMB reports 2012;45(2: 79-84

  5. Triplets of Quasars at high redshift I: Photometric data

    CERN Document Server

    Alonso, M Victoria; Sochting, Ilona; Bornancini, Carlos; Smith, Malcolm G; Lambas, Diego Garcia; Rest, Armin

    2008-01-01

    We have conducted an optical and infrared imaging in the neighbourhoods of 4 triplets of quasars. R, z', J and Ks images were obtained with MOSAIC II and ISPI at Cerro Tololo Interamerican Observatory. Accurate relative photometry and astrometry were obtained from these images for subsequent use in deriving photometric redshifts. We analyzed the homogeneity and depth of the photometric catalog by comparing with results coming from the literature. The good agreement shows that our magnitudes are reliable to study large scale structure reaching limiting magnitudes of R = 24.5, z' = 22.5, J = 20.5 and Ks = 19.0. With this catalog we can study the neighbourhoods of the triplets of quasars searching for galaxy overdensities such as groups and galaxy clusters.

  6. Complexin II plays a positive role in Ca2+-triggered exocytosis by facilitating vesicle priming

    DEFF Research Database (Denmark)

    Cai, Haijiang; Reim, Kerstin; Varoqueaux, Frederique;

    2008-01-01

    the complex and inhibiting membrane fusion. However, several other studies also suggest that CPXs are positive regulators of neurotransmitter release. Thus, whether CPXs are positive or negative regulators of exocytosis is not known, much less the stage in the vesicle life cycle at which they function. Here...... regulate the size of the primed vesicle pools and have a positive role in Ca(2+)-triggered exocytosis....

  7. Interplay between singlet and triplet excited states in a conformationally locked donor–acceptor dyad

    KAUST Repository

    Filatov, Mikhail A.

    2015-10-13

    The synthesis and photophysical characterization of a palladium(II) porphyrin – anthracene dyad bridged via short and conformationally rigid bicyclo[2.2.2]octadiene spacer were achieved. A spectroscopic investigation of the prepared molecule in solution has been undertaken to study electronic energy transfer in excited singlet and triplet states between the anthracene and porphyrin units. By using steady-state and time-resolved photoluminescence spectroscopy it was shown that excitation of the singlet excited state of the anthracene leads to energy transfer to the lower-lying singlet state of porphyrin. Alternatively, excitation of the porphyrin followed by intersystem crossing to the triplet state leads to very fast energy transfer to the triplet state of anthracene. The rate of this energy transfer has been determined by transient absorption spectroscopy. Comparative studies of the dynamics of triplet excited states of the dyad and reference palladium octaethylporphyrin (PdOEP) have been performed.

  8. The large- and small-scale CaII K structure of the Milky Way from observations of Galactic and Magellanic sightlines

    CERN Document Server

    Smoker, J V; Fox, A J

    2015-01-01

    Aims: By utilising spectra of early-type stellar probes of known distances in the same region of the sky, the large and small-scale (pc) structure of the Galactic ISM can be investigated. This paper determines the variation in line strength of CaII at 3933.661 A, as a function of probe separation for a sample of stars, including many sightlines in the Magellanic Clouds. Methods: FLAMES-GIRAFFE data taken with the VLT towards early-type stars in 3 Galactic & 4 Magellanic open clusters in CaII are used to obtain the velocity, EW, column density and line width of IS Galactic Ca for a total of 657 stars, of which 443 are Magellanic sightlines. In each cluster there are 43-110 stars observed. Additionally, FEROS and UVES CaII & NaI spectra of 21 Galactic & 154 Magellanic early-type stars are presented and combined with data from the literature to study the Ca column density/parallax relationship. Results: For the four Magellanic clusters studied with FLAMES, the strength of the Galactic IS CaII K EW ov...

  9. Diphotons from an Electroweak Triplet-Singlet

    Energy Technology Data Exchange (ETDEWEB)

    Howe, Kiel [Fermilab; Knapen, Simon [UC, Berkeley; Robinson, Dean J. [UC, Berkeley

    2016-03-29

    The neutral component of a real pseudoscalar electroweak (EW) triplet can produce a diphoton excess at 750 GeV, if it is somewhat mixed with an EW singlet pseudoscalar. This triplet-singlet mixing allows for greater freedom in the diboson branching ratios than the singlet-only case, but it is still possible to probe the parameter space extensively with 300 fb$^{-1}$. The charged component of the triplet is pair-produced at the LHC, which results in a striking signal in the form of a pair of $W\\gamma$ resonances with an irreducible rate of 0.27 fb. Other signatures include multiboson final states from cascade decays of the triplet-singlet neutral states. A large class of composite models feature both EW singlet and triplet pseudo-Nambu Goldstone bosons in their spectrum, with the diboson couplings generated by axial anomalies.

  10. The effect of Ca2+ ions and ionic strength on Mn(II) oxidation by spores of the marine Bacillus sp. SG-1

    Science.gov (United States)

    Toyoda, Kazuhiro; Tebo, Bradley M.

    2013-01-01

    Manganese(IV) oxides, believed to form primarily through microbial activities, are extremely important mineral phases in marine environments where they scavenge a variety of trace elements and thereby control their distributions. The presence of various ions common in seawater are known to influence Mn oxide mineralogy yet little is known about the effect of these ions on the kinetics of bacterial Mn(II) oxidation and Mn oxide formation. We examined factors affecting bacterial Mn(II) oxidation by spores of the marine Bacillus sp. strain SG-1 in natural and artificial seawater of varying ionic conditions. Ca2+ concentration dramatically affected Mn(II) oxidation, while Mg2+, Sr2+, K+, Na+ and NO3- ions had no effect. The rate of Mn(II) oxidation at 10 mM Ca2+ (seawater composition) was four or five times that without Ca2+. The relationship between Ca2+ content and oxidation rate demonstrates that the equilibrium constant is small (on the order of 0.1) and the binding coefficient is 0.5. The pH optimum for Mn(II) oxidation changed depending on the amount of Ca2+ present, suggesting that Ca2+ exerts a direct effect on the enzyme perhaps as a stabilizing bridge between polypeptide components. We also examined the effect of varying concentrations of NaCl or KNO3 (0-2000 mM) on the kinetics of Mn(II) oxidation in solutions containing 10 mM Ca2+. Mn(II) oxidation was unaffected by changes in ionic strength (I) below 0.2, but it was inhibited by increasing salt concentrations above this value. Our results suggest that the critical coagulation concentration is around 200 mM of salt (I = ca. 0.2), and that the ionic strength of seawater (I > 0.2) accelerates the precipitation of Mn oxides around the spores. Under these conditions, the aggregation of Mn oxides reduces the supply of dissolved O2 and/or Mn2+ and inhibits the Mn(II) → Mn(III) step controlling the enzymatic oxidation of Mn(II). Our results suggest that the hardness and ionic strength of the aquatic environment

  11. Singlet and triplet instability theorems

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Tomonori; Hirata, So, E-mail: sohirata@illinois.edu [Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801 (United States); CREST, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012 (Japan)

    2015-09-21

    A useful definition of orbital degeneracy—form-degeneracy—is introduced, which is distinct from the usual energy-degeneracy: Two canonical spatial orbitals are form-degenerate when the energy expectation value in the restricted Hartree–Fock (RHF) wave function is unaltered upon a two-electron excitation from one of these orbitals to the other. Form-degenerate orbitals tend to have isomorphic electron densities and occur in the highest-occupied and lowest-unoccupied molecular orbitals (HOMOs and LUMOs) of strongly correlated systems. Here, we present a mathematical proof of the existence of a triplet instability in a real or complex RHF wave function of a finite system in the space of real or complex unrestricted Hartree–Fock wave functions when HOMO and LUMO are energy- or form-degenerate. We also show that a singlet instability always exists in a real RHF wave function of a finite system in the space of complex RHF wave functions, when HOMO and LUMO are form-degenerate, but have nonidentical electron densities, or are energy-degenerate. These theorems provide Hartree–Fock-theory-based explanations of Hund’s rule, a singlet instability in Jahn–Teller systems, biradicaloid electronic structures, and a triplet instability during some covalent bond breaking. They also suggest (but not guarantee) the spontaneous formation of a spin density wave (SDW) in a metallic solid. The stability theory underlying these theorems extended to a continuous orbital-energy spectrum proves the existence of an oscillating (nonspiral) SDW instability in one- and three-dimensional homogeneous electron gases, but only at low densities or for strong interactions.

  12. Singlet and triplet instability theorems

    International Nuclear Information System (INIS)

    A useful definition of orbital degeneracy—form-degeneracy—is introduced, which is distinct from the usual energy-degeneracy: Two canonical spatial orbitals are form-degenerate when the energy expectation value in the restricted Hartree–Fock (RHF) wave function is unaltered upon a two-electron excitation from one of these orbitals to the other. Form-degenerate orbitals tend to have isomorphic electron densities and occur in the highest-occupied and lowest-unoccupied molecular orbitals (HOMOs and LUMOs) of strongly correlated systems. Here, we present a mathematical proof of the existence of a triplet instability in a real or complex RHF wave function of a finite system in the space of real or complex unrestricted Hartree–Fock wave functions when HOMO and LUMO are energy- or form-degenerate. We also show that a singlet instability always exists in a real RHF wave function of a finite system in the space of complex RHF wave functions, when HOMO and LUMO are form-degenerate, but have nonidentical electron densities, or are energy-degenerate. These theorems provide Hartree–Fock-theory-based explanations of Hund’s rule, a singlet instability in Jahn–Teller systems, biradicaloid electronic structures, and a triplet instability during some covalent bond breaking. They also suggest (but not guarantee) the spontaneous formation of a spin density wave (SDW) in a metallic solid. The stability theory underlying these theorems extended to a continuous orbital-energy spectrum proves the existence of an oscillating (nonspiral) SDW instability in one- and three-dimensional homogeneous electron gases, but only at low densities or for strong interactions

  13. Gentamicin Blocks the ACh-Induced BK Current in Guinea Pig Type II Vestibular Hair Cells by Competing with Ca2+ at the l-Type Calcium Channel

    Directory of Open Access Journals (Sweden)

    Hong Yu

    2014-04-01

    Full Text Available Type II vestibular hair cells (VHCs II contain big-conductance Ca2+-dependent K+ channels (BK and L-type calcium channels. Our previous studies in guinea pig VHCs II indicated that acetylcholine (ACh evoked the BK current by triggering the influx of Ca2+ ions through l-type Ca2+ channels, which was mediated by M2 muscarinic ACh receptor (mAChRs. Aminoglycoside antibiotics, such as gentamicin (GM, are known to have vestibulotoxicity, including damaging effects on the efferent nerve endings on VHCs II. This study used the whole-cell patch clamp technique to determine whether GM affects the vestibular efferent system at postsynaptic M2-mAChRs or the membrane ion channels. We found that GM could block the ACh-induced BK current and that inhibition was reversible, voltage-independent, and dose-dependent with an IC50 value of 36.3 ± 7.8 µM. Increasing the ACh concentration had little influence on GM blocking effect, but increasing the extracellular Ca2+ concentration ([Ca2+]o could antagonize it. Moreover, 50 µM GM potently blocked Ca2+ currents activated by (--Bay-K8644, but did not block BK currents induced by NS1619. These observations indicate that GM most likely blocks the M2 mAChR-mediated response by competing with Ca2+ at the l-type calcium channel. These results provide insights into the vestibulotoxicity of aminoglycoside antibiotics on mammalian VHCs II.

  14. Relations between broad-band linear polarization and Ca II H and K emission in late-type dwarf stars

    Science.gov (United States)

    Huovelin, Juhani; Saar, Steven H.; Tuominen, Ilkka

    1988-01-01

    Broadband UBV linear polarization data acquired for a sample of late-type dwarfs are compared with contemporaneous measurements of Ca II H and K line core emission. A weighted average of the largest values of the polarization degree is shown to be the best parameter for chromospheric activity diagnosis. The average maximum polarization in the UV is found to increase from late-F to late-G stars. It is noted that polarization in the U band is considerably more sensitive to activity variations than that in the B or V bands. The results indicate that stellar magnetic fields and the resulting saturation in the Zeeman-sensitive absorption lines are the most probably source of linear polarization in late-type main-sequence stars.

  15. Crystal structure and mutational analysis of Ca2+-independent type II antifreeze protein from longsnout poacher, Brachyopsis rostratus.

    Science.gov (United States)

    Nishimiya, Yoshiyuki; Kondo, Hidemasa; Takamichi, Manabu; Sugimoto, Hiroshi; Suzuki, Mamoru; Miura, Ai; Tsuda, Sakae

    2008-10-10

    We recently found that longsnout poacher (Brachyosis rostratus) produces a Ca(2+)-independent type II antifreeze protein (lpAFP) and succeeded in expressing recombinant lpAFP using Phichia pastoris. Here, we report, for the first time, the X-ray crystal structure of lpAFP at 1.34 A resolution. The lpAFP structure displayed a relatively planar surface, which encompasses two loop regions (Cys86-Lys89 and Asn91-Cys97) and a short beta-strand (Trp109-Leu112) with three unstructured segments (Gly57-Ile58, Ala103-Ala104, and Pro113-His118). Electrostatic calculation of the protein surface showed that the relatively planar surface was divided roughly into a hydrophobic area (composed of the three unstructured segments lacking secondary structure) and a hydrophilic area (composed of the loops and beta-strand). Site-directed mutation of Ile58 with Phe at the center of the hydrophobic area decreased activity significantly, whereas mutation of Leu112 with Phe at an intermediate area between the hydrophobic and hydrophilic areas retained complete activity. In the hydrophilic area, a peptide-swap mutant in the loops retained 60% activity despite simultaneous mutations of eight residues. We conclude that the epicenter of the ice-binding site of lpAFP is the hydrophobic region, which is centered by Ile58, in the relatively planar surface. We built an ice-binding model for lpAFP on the basis of a lattice match of ice and constrained water oxygen atoms surrounding the hydrophobic area in the lpAFP structure. The model in which lpAFP has been docked to a secondary prism (2-1-10) plane, which is different from the one determined for Ca(2+)-independent type II AFP from sea raven (11-21), appears to explain the results of the mutagenesis analysis. PMID:18674542

  16. The digitized archive of the Arcetri spectroheliograms. Preliminary results from the analysis of Ca II K images

    Science.gov (United States)

    Ermolli, I.; Marchei, E.; Centrone, M.; Criscuoli, S.; Giorgi, F.; Perna, C.

    2009-05-01

    Context: The increasing interest in the recovery of historic data and the availability of new hardware resources is leading to projects to digitize photographic archives of astronomical observations. In addition to preservation, solar archives are digitized because the observations stored in such archives have the potential of providing unique information about solar magnetism, which can improve knowledge about long-term solar changes. Aims: The solar tower of the Arcetri Astrophysical Observatory produced synoptic observations of the solar atmosphere from 1926 to 1974. The photographic archive contains about 13 000 plates of full-disk Ca II K and Hα spectroheliograms acquired during about 5000 observing days. The program for the digitization and distribution of the images of this archive was carried out at the Rome Astronomical Observatory and is now complete. Methods: Nearly 13 000 plates were scanned with a commercial device and stored on DVD, as well as in a database accessible online. Image processing was developed for the reduction of the data and their photographic calibration. Results: The obtained digital archive provides the astronomical community with the Arcetri historical solar observations and with measurements of solar features identified in such observations. As an example, we show some preliminary results concerning the temporal variability of facular regions identified in the time-series of Ca II K observations. Conclusions: Existing programs studying solar activity and variability, as well as new scientific projects, will benefit from the Arcetri digital archive, since it extends the temporal baseline of digital full-disk solar observations, and it provides data for the inter-calibration of results obtained from measurements performed in similar observations.

  17. Fusion pore expansion is a slow, discontinuous, and Ca2+-dependent process regulating secretion from alveolar type II cells.

    Science.gov (United States)

    Haller, T; Dietl, P; Pfaller, K; Frick, M; Mair, N; Paulmichl, M; Hess, M W; Furst, J; Maly, K

    2001-10-15

    In alveolar type II cells, the release of surfactant is considerably delayed after the formation of exocytotic fusion pores, suggesting that content dispersal may be limited by fusion pore diameter and subject to regulation at a postfusion level. To address this issue, we used confocal FRAP and N-(3-triethylammoniumpropyl)-4-(4-[dibutylamino]styryl) pyridinium dibromide (FM 1-43), a dye yielding intense localized fluorescence of surfactant when entering the vesicle lumen through the fusion pore (Haller, T., J. Ortmayr, F. Friedrich, H. Volkl, and P. Dietl. 1998. Proc. Natl. Acad. Sci. USA. 95:1579-1584). Thus, we have been able to monitor the dynamics of individual fusion pores up to hours in intact cells, and to calculate pore diameters using a diffusion model derived from Fick's law. After formation, fusion pores were arrested in a state impeding the release of vesicle contents, and expanded at irregular times thereafter. The expansion rate of initial pores and the probability of late expansions were increased by elevation of the cytoplasmic Ca2+ concentration. Consistently, content release correlated with the occurrence of Ca2+ oscillations in ATP-treated cells, and expanded fusion pores were detectable by EM. This study supports a new concept in exocytosis, implicating fusion pores in the regulation of content release for extended periods after initial formation. PMID:11604423

  18. Higgs triplets and limits from precision measurements

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Mu-Chun; /Fermilab; Dawson, Sally; Krupovnickas, Tadas; /Brookhaven

    2006-04-01

    In this letter, they present the results on a global fit to precision electroweak data in a Higgs triplet model. In models with a triplet Higgs boson, a consistent renormalization scheme differs from that of the Standard Model and the global fit shows that a light Higgs boson with mass of 100-200 GeV is preferred. Triplet Higgs bosons arise in many extensions of the Standard Model, including the left-right model and the Little Higgs models. The result demonstrates the importance of the scalar loops when there is a large mass splitting between the heavy scalars. It also indicates the significance of the global fit.

  19. Mechanochemical synthesis and intercalation of Ca(II)Fe(III)-layered double hydroxides

    Science.gov (United States)

    Ferencz, Zs.; Szabados, M.; Varga, G.; Csendes, Z.; Kukovecz, Á.; Kónya, Z.; Carlson, S.; Sipos, P.; Pálinkó, I.

    2016-01-01

    A mechanochemical method (grinding the components without added water - dry grinding, followed by further grinding in the presence of minute amount of water or NaOH solution - wet grinding) was used in this work for the preparation and intercalation of CaFe-layered double hydroxides (LDHs). Both the pristine LDHs and the amino acid anion (cystinate and tyrosinate) intercalated varieties were prepared by the two-step grinding procedure in a mixer mill. By systematically changing the conditions of the preparation method, a set of parameters could be determined, which led to the formation of close to phase-pure LDH. The optimisation procedure was also applied for the intercalation processes of the amino acid anions. The resulting materials were structurally characterised by a range of methods (X-ray diffractometry, scanning electron microscopy, energy dispersive analysis, thermogravimetry, X-ray absorption and infra-red spectroscopies). It was proven that this simple mechanochemical procedure was able to produce complex organic-inorganic nanocomposites: LDHs intercalated with amino acid anions.

  20. Acute effects of taurine on sarcoplasmic reticulum Ca2+ accumulation and contractility in human type I and type II skeletal muscle fibers.

    Science.gov (United States)

    Dutka, T L; Lamboley, C R; Murphy, R M; Lamb, G D

    2014-10-01

    Taurine occurs in high concentrations in muscle and is implicated in numerous physiological processes, yet its effects on many aspects of contractility remain unclear. Using mechanically skinned segments of human vastus lateralis muscle fibers, we characterized the effects of taurine on sarcoplasmic reticulum (SR) Ca2+ accumulation and contractile apparatus properties in type I and type II fibers. Prolonged myoplasmic exposure (>10 min) to taurine substantially increased the rate of accumulation of Ca2+ by the SR in both fiber types, with no change in the maximum amount accumulated; no such effect was found with carnosine. SR Ca2+ accumulation was similar with 10 or 20 mM taurine, but was significantly slower at 5 mM taurine. Cytoplasmic taurine (20 mM) had no detectable effects on the responsiveness of the Ca2+ release channels in either fiber type. Taurine caused a small increase in Ca2+ sensitivity of the contractile apparatus in type I fibers, but type II fibers were unaffected; maximum Ca(2+)-activated force was unchanged in both cases. The effects of taurine on SR Ca2+ accumulation (1) only became apparent after prolonged cytoplasmic exposure, and (2) persisted for some minutes after complete removal of taurine from the cytoplasm, consistent with the hypothesis that the effects were due to an action of taurine from inside the SR. In summary, taurine potentiates the rate of SR Ca2+ uptake in both type I and type II human fibers, possibly via an action from within the SR lumen, with the degree of potentiation being significantly reduced at low physiological taurine levels. PMID:25123198

  1. Dark Matter in Inert Triplet Models

    CERN Document Server

    Araki, Takeshi; Nagao, Keiko I

    2011-01-01

    We study the inert triplet models, in which the standard model (SM) is extended to have a new SU(2)L triplet scalar (Y=0 or 2) with an Z2 symmetry. We show that the neutral component of the triplet can be a good dark matter candidate. In particular, for the hypercharge Y=0 triplet model, the WMAP data favors the region where the dark matter mass is around 5.5 TeV, which is also consistent with the direct detection experiments. In contrast, for the Y=2 model, although dark matter with its mass around 2.8 TeV is allowed by WMAP, it is excluded by the direct detection experiments because the spin-independent cross section is enhanced by the Z mediated tree-level scattering process.

  2. Dark matter in inert triplet models

    International Nuclear Information System (INIS)

    We study the inert triplet models, in which the standard model is extended to have a new SU(2)L triplet scalar (Y=0 or 2) with an Z2 symmetry. We show that the neutral component of the triplet can be a good dark matter candidate. In particular, for the hypercharge Y=0 triplet model, the WMAP data favors the region where the dark matter mass is around 5.5 TeV, which is also consistent with the direct detection experiments. In contrast, for the Y=2 model, although dark matter with its mass around 2.8 TeV is allowed by WMAP, it is excluded by the direct detection experiments because the spin-independent cross section is enhanced by the Z-mediated tree-level scattering process.

  3. Helium-like triplet diagnostics

    CERN Document Server

    Dubau, J; Dubau, Jacques; Porquet, Delphine

    2002-01-01

    The 1s2-1s2l lines are the most intense He-like ions lines. They are used as spectroscopic diagnostics for solar active regions as well as for different laboratory plasmas. Nowadays, it exits very high spectral resolution instruments and, for intense X-ray sources, one can do spectroscopic diagnostics from line ratios. With XMM (RGS) and Chandra (LETGS, HETGS) spectral resolutions and for several atomic elements, it is particularly possible to separate a 3 blended line set, the so-called He-like triplet: Resonance (r), Intercombination (i) and Forbidden (f), which are dominated respectively by lines issued from the following levels : 1s2p 1P1, 1s2p 3P1,2 and 1s2s 3S1. We shall show that the measurement of two different ratios between these 3 lines (R = f/i and G = (f + i)/r) give quantitative informations on the nature of the emitting plasma (photo-ionized or collisional) and on its electronic density and temperature. A more refined analysis must also include satellite line contributions.

  4. New Algorithms on Rooted Triplet Consistency

    OpenAIRE

    Tazehkand, Soheil Jahangiri; Hashemi, Seyed Naser; Poormohammadi, Hadi

    2012-01-01

    An evolutionary tree (phylogenetic tree) is a binary, rooted, unordered tree that models the evolutionary history of currently living species in which leaves are labeled by species. In this paper, we investigate the problem of finding the maximum consensus evolutionary tree from a set of given rooted triplets. A rooted triplet is a phylogenetic tree on three leaves and shows the evolutionary relationship of the corresponding three species. The mentioned problem is known to be APX-hard. We pre...

  5. Probing the accessibility of the Mn(4)Ca cluster in photosystem II : Channels calculation, noble gas derivatization, and cocrystallization with DMSO

    NARCIS (Netherlands)

    Gabdulkhakov, Azat; Guskov, Albert; Broser, Matthias; Kern, Jan; Müh, Frank; Saenger, Wolfram; Zouni, Athina

    2009-01-01

    Using the 2.9 A resolution structure of the membrane-intrinsic protein-cofactor complex photosystem II (PSII) from the cyanobacterium Thermosynechococcus elongatus, we calculated and characterized nine possible substrate/product channels leading to/away from the Mn(4)Ca cluster, where water is oxidi

  6. Intracellular translocation of calmodulin and Ca2+/calmodulin-dependent protein kinase II during the development of hypertrophy in neonatal cardiomyocytes

    International Nuclear Information System (INIS)

    We have recently shown that stimulation of cultured neonatal cardiomyocytes with endothelin-1 (ET-1) first produces conformational disorder within the ryanodine receptor (RyR2) and diastolic Ca2+ leak from the sarcoplasmic reticulum (SR), then develops hypertrophy (HT) in the cardiomyocytes (Hamada et al., 2009 ). The present paper addresses the following question. By what mechanism does crosstalk between defective operation of RyR2 and activation of the HT gene program occur? Here we show that the immuno-stain of calmodulin (CaM) is localized chiefly in the cytoplasmic area in the control cells; whereas, in the ET-1-treated/hypertrophied cells, major immuno-staining is localized in the nuclear region. In addition, fluorescently labeled CaM that has been introduced into the cardiomyocytes using the BioPORTER system moves from the cytoplasm to the nucleus with the development of HT. The immuno-confocal imaging of Ca2+/CaM-dependent protein kinase II (CaMKII) also shows cytoplasm-to-nucleus shift of the immuno-staining pattern in the hypertrophied cells. In an early phase of hypertrophic growth, the frequency of spontaneous Ca2+ transients increases, which accompanies with cytoplasm-to-nucleus translocation of CaM. In a later phase of hypertrophic growth, further increase in the frequency of spontaneous Ca2+ transients results in the appearance of trains of Ca2+ spikes, which accompanies with nuclear translocation of CaMKII. The cardio-protective reagent dantrolene (the reagent that corrects the de-stabilized inter-domain interaction within the RyR2 to a normal mode) ameliorates aberrant intracellular Ca2+ events and prevents nuclear translocation of both CaM and CaMKII, then prevents the development of HT. These results suggest that translocation of CaM and CaMKII from the cytoplasm to the nucleus serves as messengers to transmit the pathogenic signal elicited in the surface membrane and in the RyR2 to the nuclear transcriptional sites to activate HT program.

  7. ELECTROCHEMICAL BEHAVIOR AND KINETICS OF THE INTERVALENCE CHARGE TRANSFER FOR THE SM(III)/SM(II) REDOX COUPLE IN LiF-CaF2 MELT

    OpenAIRE

    Stulov Yuriy Vyacheslavovich; Korenko Michal; Kubikova Blanca; Kuznetsov Sergey Aleksandrovich

    2015-01-01

    This article is focused on the electrochemical investigation (cyclic voltammetry) of the redox couple Sm(III)/Sm(II) in an eutectic LiF–CaF2 melt containing SmF3. The first step of reduction for Sm(III) ions, involving one electron exchange in soluble/soluble Sm(III)/Sm(II) system, was found on a tungsten electrode. The study of the Sm(II)/Sm(0) electrode reaction was not feasible, since it’s the redox potential is in the same range of the solvent decomposition. The first step was fo...

  8. Structure and Orientation of the Mn4Ca Cluster in Plant Photosystem II Membranes Studied by Polarized Range-extended X-ray Absorption Spectroscopy*[S]♦

    OpenAIRE

    Pushkar, Yulia; Yano, Junko; Glatzel, Pieter; Messinger, Johannes; Lewis, Azul; Sauer, Kenneth; Bergmann, Uwe; Yachandra, Vittal

    2006-01-01

    X-ray absorption spectroscopy has provided important insights into the structure and function of the Mn4Ca cluster in the oxygen-evolving complex of Photosystem II (PS II). The range of manganese extended x-ray absorption fine structure data collected from PSII until now has been, however, limited by the presence of iron in PS II. Using a crystal spectrometer with high energy resolution to detect solely the manganese Kα fluorescence, we are able to extend the extended x-ray absorption fine st...

  9. The impact of hydroquinone on acetylcholine esterase and certain human carbonic anhydrase isoenzymes (hCA I, II, IX, and XII).

    Science.gov (United States)

    Scozzafava, Andrea; Kalın, Pınar; Supuran, Claudiu T; Gülçin, İlhami; Alwasel, Saleh H

    2015-12-01

    Carbonic anhydrases (CAs) are widespread and the most studied members of a great family of metalloenzymes in higher vertebrates including humans. CAs were investigated for their inhibition of all of the catalytically active mammalian isozymes of the Zn(2+)-containing CA, (CA, EC 4.2.1.1). On the other hand, acetylcholinesterase (AChE. EC 3.1.1.7), a serine protease, is responsible for ACh hydrolysis and plays a fundamental role in impulse transmission by terminating the action of the neurotransmitter ACh at the cholinergic synapses and neuromuscular junction. In the present study, the inhibition effect of the hydroquinone (benzene-1,4-diol) on AChE activity was evaluated and effectively inhibited AChE with Ki of 1.22 nM. Also, hydroquinone strongly inhibited some human cytosolic CA isoenzymes (hCA I and II) and tumour-associated transmembrane isoforms (hCA IX, and XII), with Kis in the range between micromolar (415.81 μM) and nanomolar (706.79 nM). The best inhibition was observed in cytosolic CA II. PMID:25586344

  10. Thiol-Activatable Triplet-Triplet Annihilation Upconversion with Maleimide-Perylene as the Caged Triplet Acceptor/Emitter.

    Science.gov (United States)

    Mahmood, Zafar; Zhao, Jianzhang

    2016-01-15

    Efficient thiol-activated triplet-triplet annihilation (TTA) upconversion system was devised with maleimide-caged perylene (Py-M) as the thiol-activatable triplet acceptor/emitter and with diiodoBodipy as the triplet photosensitizer. The photophysical processes were studied with steady-state UV-vis absorption spectroscopy, fluorescence spectroscopy, electrochemical properties, and nanosecond transient absorption spectroscopy. The triplet acceptor/emitter Py-M shows week fluorescence (ΦF = 0.8%), and no upconversion (ΦUC = 0%) was observed. The quenching of fluorescence of Py-M is due to photoinduced electron-transfer (PET) process from perylene to maleimide-caging unit, which quenches the singlet excited state of perylene. The fluorescence of Py-M was enhanced by 200-fold (ΦF = 97%) upon addition of thiols such as 2-mercaptoethanol, and the ΦUC was increased to 5.9%. The unique feature of this thiol-activated TTA upconversion is that the activation is based on addition reaction of the thiols with the caged acceptor/emitter, and no side products were formed. The previously reported cleavage approach gives side products which are detrimental to the TTA upconversion. With nanosecond transient absorption spectroscopy, we found that the triplet excited state of Py-M was not quenched by any PET process, which is different from singlet excited state (fluorescence) of Py-M. The results are useful for study of the triplet excited states of organic chromophores and for activatable TTA upconversion. PMID:26694534

  11. Chemically induced dynamic electron polarization investigation of the triplet-radical system in the solution of the triplet quencher

    Institute of Scientific and Technical Information of China (English)

    LU, Tong-Xing; CUI, Zhi-Feng; XU, Xin-Sheng; ZHANG, Xian-Yi

    2000-01-01

    The chemically induced dynamic electron polariztiion (CIDEP) of the triplet molecule/triplet quencher/2,2,6,6-te tranethyl-1-piperidinyioxyl (TEMPO) systems were measured using the high time-resolved FESR spectrometer. The competi tion between the radical-triplet pair mechanism (RTPM) and triplet mechanism (TM) or radical pair mechanism (RPM) polarization in the solution of the triplet quencher was investi gated, and the relationship between reaction rate of the radi cal-triplet pair and quenching rate of triplet was deduced.

  12. 2,5-hexanedione (HD) treatment alters calmodulin, Ca2+/calmodulin-dependent protein kinase II, and protein kinase C in rats' nerve tissues

    International Nuclear Information System (INIS)

    Calcium-dependent mechanisms, particularly those mediated by Ca2+/calmodulin (CaM)-dependent protein kinase II (CaMKII), have been implicated in neurotoxicant-induced neuropathy. However, it is unknown whether similar mechanisms exist in 2,5-hexanedione (HD)-induced neuropathy. For that, we investigated the changes of CaM, CaMKII, protein kinase C (PKC) and polymerization ratios (PRs) of NF-L, NF-M and NF-H in cerebral cortex (CC, including total cortex and some gray), spinal cord (SC) and sciatic nerve (SN) of rats treated with HD at a dosage of 1.75 or 3.50 mmol/kg for 8 weeks (five times per week). The results showed that CaM contents in CC, SC and SN were significantly increased, which indicated elevation of Ca2+ concentrations in nerve tissues. CaMKII contents and activities were also increased in CC and were positively correlated with gait abnormality, but it could not be found in SC and SN. The increases of PKC contents and activities were also observed in SN and were positively correlated with gait abnormality. Except for that of NF-M in CC, the PRs of NF-L, NF-M and NF-H were also elevated in nerve tissues, which was consistent with the activation of protein kinases. The results suggested that CaMKII might be partly (in CC but not in SC and SN) involved in HD-induced neuropathy. CaMKII and PKC might mediate the HD neurotoxicity by altering the NF phosphorylation status and PRs

  13. The Calcium Triplet metallicity calibration for galactic bulge stars

    CERN Document Server

    Vasquez, S; Hill, V; Gonzalez, O A; Saviane, I; Rejkuba, M; Battaglia, G

    2015-01-01

    We present a new calibration of the Calcium II Triplet equivalent widths versus [Fe/H], constructed upon K giant stars in the Galactic bulge. This calibration will be used to derive iron abundances for the targets of the GIBS survey, and in general it is especially suited for solar and supersolar metallicity giants, typical of external massive galaxies. About 150 bulge K giants were observed with the GIRAFFE spectrograph at VLT, both at resolution R~20,000 and at R~6,000. In the first case, the spectra allowed us to perform direct determination of Fe abundances from several unblended Fe lines, deriving what we call here high resolution [Fe/H] measurements. The low resolution spectra allowed us to measure equivalent widths of the two strongest lines of the near infrared Calcium II triplet at 8542 and 8662 A. By comparing the two measurements we derived a relation between Calcium equivalent widths and [Fe/H] that is linear over the metallicity range probed here, -1<[Fe/H]<+0.7. By adding a small second or...

  14. The wings of Ca II H and K as photospheric diagnostics and the reliability of one-dimensional photosphere modeling

    CERN Document Server

    Sheminova, V A

    2012-01-01

    The extended wings of the Ca II H and K lines provide excellent diagnostics of the temperature stratification of the photosphere of the Sun and of other cool stars, thanks to their LTE opacities and source functions and their large span in formation height. The aim of this study is to calibrate the usage of the H and K wings in one-dimensional interpretation of spatially averaged spectra and in deriving per-pixel stratifications from resolved spectra. I use multi-dimensional simulations of solar convection to synthesize the H and K wings, derive one-dimensional models from these wings as if they were observed, and compare the resulting models to the actual simulation input. I find that spatially-averaged models constructed from the synthesized wings generally match the simulation averages well, except for the deepest layers of the photosphere where large thermal inhomogeneities and Planck-function nonlinearity gives large errors. The larger the inhomogeneity, the larger the latter. The presence of strong netw...

  15. HI Observations of the Ca II absorbing galaxies Mrk 1456 and SDSS J211701.26-002633.7

    CERN Document Server

    Cherinka, Brian; Rosenberg, Jessica

    2009-01-01

    In an effort to study Damped Lyman Alpha galaxies at low redshift, we have been using the Sloan Digital Sky Survey to identify galaxies projected onto QSO sightlines and to characterize their optical properties. For low redshift galaxies, the HI 21cm emission line can be used as an alternate tool for identifying possible DLA galaxies, since HI emitting galaxies typically exhibit HI columns that are larger than the classical DLA limit. Here we report on follow-up HI 21 cm emission line observations of two DLA candidates that are both low-redshift spiral galaxies, Mrk 1456 and SDSS J211701.26-002633.7. The observations were made using the Green Bank and Arecibo Telescopes, respectively. Analysis of their HI properties reveal the galaxies to be about one and two M_HI* galaxies, respectively, and to have average HI mass, gas-richness, and gas mass fraction for their morphological types. We consider Mrk 1456 and SDSS J211701.26-002633.7 to be candidate DLA systems based upon the strength of the CaII absorption lin...

  16. Full-Disk Chromospheric Vector Magnetograms with Ca II 854.2 nm line: Some Promising Applications

    Science.gov (United States)

    Gosain, Sanjay; Harvey, J. W.; Harker, Brian; Pillet, V. M.; Pevtsov, Alexei A.; Marble, Andrew R.; Bertello, Luca; + SOLIS-Team

    2016-05-01

    Over the last decade, the focus of solar magnetometry has shifted outward from the photosphere to the chromospheric layers. The reasons for this are many. With regards to instrumentation faster detectors with more sensitivity have become available, as have fast electro-optic modulators. Also, there are several potential benefits of observing vector fields in the chromospheric layer as the magnetic field is more force-free in this layer as compared to the photosphere. Coronal force-free field extrapolations are more reliable using chromospheric fields as the lower boundary condition and free magnetic energy is readily computed using the magnetic virial theorem. Recently, a full Stokes polarimeter for the chromospheric Ca II 854.2 nm spectral line was developed and installed in the Vector Spectromagnetograph (VSM) instrument on the Synoptic Optical Long-term Investigations of the Sun (SOLIS) telescope. We present details of this new polarimeter, full disk spectropolarimetric observations and vector magnetograms of the chromosphere, and examples of some promising applications (e.g., maps of normal component of electric current density in the chromosphere, free magnetic energy estimated using virial theorem, and non-potentiality parameter magnetic shear angle).This work utilizes SOLIS data obtained by the NSO Integrated Synoptic Program (NISP), managed by the National Solar Observatory, which is operated by the Association of Universities for Research in Astronomy (AURA), Inc. under a cooperative agreement with the National Science Foundation

  17. Calcium controls the assembly of the photosynthetic water-oxidizing complex: a cadmium(II) inorganic mutant of the Mn4Ca core.

    Science.gov (United States)

    Bartlett, John E; Baranov, Sergei V; Ananyev, Gennady M; Dismukes, G Charles

    2008-03-27

    Perturbation of the catalytic inorganic core (Mn4Ca1OxCly) of the photosystem II-water-oxidizing complex (PSII-WOC) isolated from spinach is examined by substitution of Ca2+ with cadmium(II) during core assembly. Cd2+ inhibits the yield of reconstitution of O2-evolution activity, called photoactivation, starting from the free inorganic cofactors and the cofactor-depleted apo-WOC-PSII complex. Ca2+ affinity increases following photooxidation of the first Mn2+ to Mn3+ bound to the 'high-affinity' site. Ca2+ binding occurs in the dark and is the slowest overall step of photoactivation (IM1-->IM1* step). Cd2+ competitively blocks the binding of Ca2+ to its functional site with 10- to 30-fold higher affinity, but does not influence the binding of Mn2+ to its high-affinity site. By contrast, even 10-fold higher concentrations of Cd2+ have no effect on O2-evolution activity in intact PSII-WOC. Paradoxically, Cd2+ both inhibits photoactivation yield, while accelerating the rate of photoassembly of active centres 10-fold relative to Ca2+. Cd2+ increases the kinetic stability of the photooxidized Mn3+ assembly intermediate(s) by twofold (mean lifetime for dark decay). The rate data provide evidence that Cd2+ binding following photooxidation of the first Mn3+, IM1-->IM1*, causes three outcomes: (i) a longer intermediate lifetime that slows IM1 decay to IM0 by charge recombination, (ii) 10-fold higher probability of attaining the degrees of freedom (either or both cofactor and protein d.f.) needed to bind and photooxidize the remaining 3 Mn2+ that form the functional cluster, and (iii) increased lability of Cd2+ following Mn4 cluster assembly results in (re)exchange of Cd2+ by Ca2+ which restores active O2-evolving centres. Prior EPR spectroscopic data provide evidence for an oxo-bridged assembly intermediate, Mn3+(mu-O2(-))Ca2+, for IM1*. We postulate an analogous inhibited intermediate with Cd2+ replacing Ca2+. PMID:17954439

  18. Colored triplets with integral quantum numbers

    International Nuclear Information System (INIS)

    The systematics of low-lying hadron spectra and the relations between mass, cross-section and magnetic moment in terms of ''constituent'' quarks on one hand, and abstraction of the properties of hadronic weak and electromagnetic current in terms of ''current'' quarks on the other hand have been extremely useful. In the category of three triplet models, there are several versions with the varying degree of similarity and difference among them. These include; (1) the paraquarks of order three, (2) the three triplets with SU(3)' x SU(3)'' symmetry, (3) SUB version by Cabibbo et al., and (4) perfect ''color'' symmetry by Gell-Mann. The physical difference among these various versions of the three triplet models and their consequence are discussed with respect to some of the current theoretical and experimental topics. (Iwase, T.)

  19. Spin accumulation in triplet Josephson junction

    International Nuclear Information System (INIS)

    We employ a Hamiltonian method to study the equal-spin pairing triplet Josephson junction with different orbital symmetries of pair potentials. Both the spin/charge supercurrent and possible spin accumulation at the interface of the junction are analyzed by means of the Keldysh Green's function. It is found that a spontaneous angle-resolved spin accumulation can form at the junction's interface when the orbital symmetries of Cooper pairs in two triplet superconductors are different, the physical origin is the combined effect of the different orbital symmetries and different spin states of Cooper pairs due to the misalignment of two d vectors in triplet leads. An abrupt current reversal effect induced by misalignment of d vectors is observed and can survive in a strong interface barrier scattering because the zero-energy state appears at the interface of the junction. These properties of the p-wave Josephson junction may be helpful for identifying the order parameter symmetry.

  20. Triplet correlation functions in liquid water

    Energy Technology Data Exchange (ETDEWEB)

    Dhabal, Debdas; Chakravarty, Charusita, E-mail: charus@chemistry.iitd.ac.in [Department of Chemistry, Indian Institute of Technology-Delhi, New Delhi 110016 (India); Singh, Murari [School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067 (India); Wikfeldt, Kjartan Thor [Science Institute, University of Iceland, 107 Reykjavik (Iceland)

    2014-11-07

    Triplet correlations have been shown to play a crucial role in the transformation of simple liquids to anomalous tetrahedral fluids [M. Singh, D. Dhabal, A. H. Nguyen, V. Molinero, and C. Chakravarty, Phys. Rev. Lett. 112, 147801 (2014)]. Here we examine triplet correlation functions for water, arguably the most important tetrahedral liquid, under ambient conditions, using configurational ensembles derived from molecular dynamics (MD) simulations and reverse Monte Carlo (RMC) datasets fitted to experimental scattering data. Four different RMC data sets with widely varying hydrogen-bond topologies fitted to neutron and x-ray scattering data are considered [K. T. Wikfeldt, M. Leetmaa, M. P. Ljungberg, A. Nilsson, and L. G. M. Pettersson, J. Phys. Chem. B 113, 6246 (2009)]. Molecular dynamics simulations are performed for two rigid-body effective pair potentials (SPC/E and TIP4P/2005) and the monatomic water (mW) model. Triplet correlation functions are compared with other structural measures for tetrahedrality, such as the O–O–O angular distribution function and the local tetrahedral order distributions. In contrast to the pair correlation functions, which are identical for all the RMC ensembles, the O–O–O triplet correlation function can discriminate between ensembles with different degrees of tetrahedral network formation with the maximally symmetric, tetrahedral SYM dataset displaying distinct signatures of tetrahedrality similar to those obtained from atomistic simulations of the SPC/E model. Triplet correlations from the RMC datasets conform closely to the Kirkwood superposition approximation, while those from MD simulations show deviations within the first two neighbour shells. The possibilities for experimental estimation of triplet correlations of water and other tetrahedral liquids are discussed.

  1. Spontaneous Triplets Carried in a Uterus Didelphys

    OpenAIRE

    Jessica R. Jackson; Brittney Williams; James Thorp

    2014-01-01

    Background: Spontaneous triplets in a uterus didelphys are an extremely rare finding. Only four other cases are reported in the literature. Case: A 24 year old gravida 3 para 2-0-0-2 conceived spontaneous triplets in a uterine didelphys. She developed cervical insufficiency and underwent cerclage placement at 17 weeks. After spontaneous rupture of membranes at 29 weeks gestation, she underwent repeat cesarean section, with delivery of three viable fetuses. Mother and all three babies are c...

  2. Ultrabright fluorescent OLEDS using triplet sinks

    Science.gov (United States)

    Zhang, Yifan; Forrest, Stephen R; Thompson, Mark

    2013-06-04

    A first device is provided. The first device further comprises an organic light emitting device. The organic light emitting device further comprises an anode, a cathode, and an emissive layer disposed between the anode and the cathode. The emissive layer further comprises an organic host compound, an organic emitting compound capable of fluorescent emission at room temperature, and an organic dopant compound. The triplet energy of the dopant compound is lower than the triplet energy of the host compound. The dopant compound does not strongly absorb the fluorescent emission of the emitting compound.

  3. Birth weight in a large series of triplets

    Directory of Open Access Journals (Sweden)

    van Beijsterveldt Catharina EM

    2011-04-01

    Full Text Available Abstract Background Triplets are often born premature and with a low birth weight. Because the incidence of triplet births is rare, there are relatively few studies describing triplet birth weight characteristics. Earlier studies are often characterized by small sample sizes and lack information on important background variables such as zygosity. The objective of this study is to examine factors associated with birth weight in a large, population-based sample of triplets registered with the Netherlands Twin Register (NTR. Methods In a sample of 1230 triplets from 410 families, the effects of assisted reproductive techniques, zygosity, birth order, gestational age, sex, maternal smoking and alcohol consumption during pregnancy on birth weight were assessed. The resemblance among triplets for birth weight was estimated as a function of zygosity. Birth weight discordance within families was studied by the pair-wise difference between triplets, expressed as a percentage of the birth weight of the heaviest child. We compare data from triplets registered with the NTR with data from population records, which include live births, stillbirths and children that have deceased within days after birth. Results There was no effect of assisted reproductive techniques on triplet birth weight. At gestational age 24 to 40 weeks triplets gained on average 130 grams per week; boys weighed 110 grams more than girls and triplets of smoking mothers weighted 104 grams less than children of non-smoking mothers. Monozygotic triplets had lower birth weights than di- and trizygotic triplets and birth weight discordance was smaller in monozygotic triplets than in di- and trizygotic triplets. The correlation in birth weight among monozygotic and dizygotic triplets was 0.42 and 0.32, respectively. In nearly two-thirds of the families, the heaviest and the lightest triplet had a birth weight discordance over 15%. The NTR sample is representative for the Dutch triplet

  4. Nefiracetam activation of CaM kinase II and protein kinase C mediated by NMDA and metabotropic glutamate receptors in olfactory bulbectomized mice.

    Science.gov (United States)

    Moriguchi, Shigeki; Han, Feng; Shioda, Norifumi; Yamamoto, Yui; Nakajima, Takeharu; Nakagawasai, Osamu; Tadano, Takeshi; Yeh, Jay Z; Narahashi, Toshio; Fukunaga, Kohji

    2009-07-01

    Aberrant behaviors related to learning and memory in olfactory bulbectomized (OBX) mice have been documented in the previous studies. We reported that the impairment of long-term potentiation (LTP) of hippocampal CA1 regions from OBX mice was associated with down-regulation of CaM kinase II (CaMKII) and protein kinase C (PKC) activities. We now demonstrated that the nootropic drug, nefiracetam, significantly improved spatial reference memory-related behaviors as assessed by Y-maze and novel object recognition task in OBX mice. Nefiracetam also restored hippocampal LTP injured in OBX mice. Nefiracetam treatment restored LTP-induced PKCalpha (Ser657) and NR1 (Ser896) phosphorylation as well as increase in their basal phosphorylation in the hippocampal CA1 region of OBX mice. Likewise, nefiracetam improved LTP-induced CaMKIIalpha (Thr286) autophosphorylation and GluR1 (Ser831) phosphorylation and increased their basal phosphorylation. The enhancement of PKCalpha (Ser657) and CaMKIIalpha (Thr286) autophosphorylation by nefiracetam was inhibited by treatment with (+/-)-alpha-Methyl-(4-carboxyphenyl)glycine and DL-2-Amino-5-phosphonovaleric acid, respectively. The enhancement of LTP induced by nefiracetam is inhibited by treatment with 2-methyl-6-(phenylethynyl)-pyridine, but not by treatment with LY367385, suggesting that metabotropic glutamate receptor 5 (mGluR5) but not mGluR1 is involved in the nefiracetam-induced LTP enhancement. Taken together, nefiracetam ameliorates OBX-induced deficits in memory-related behaviors and impairment of LTP in the hippocampal CA1 region through activation of NMDAR and mGluR5, thereby leading to an increase in activities of CaMKIIalpha (Thr286) and PKCalpha (Ser657), respectively. PMID:19457128

  5. Activation of ROS/NF-kappaB and Ca2+/CaM kinase II are necessary for VCAM-1 induction in IL-1beta-treated human tracheal smooth muscle cells.

    Science.gov (United States)

    Luo, Shue-Fen; Chang, Chia-Chi; Lee, I-Ta; Lee, Chiang-Wen; Lin, Wei-Ning; Lin, Chih-Chung; Yang, Chuen-Mao

    2009-05-15

    Histone acetylation regulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs) plays a critical role in the expression of inflammatory genes, such as vascular cell adhesion molecule-1 (VCAM-1). Oxidative processes have been shown to induce VCAM-1 expression. Here, we investigated the mechanisms underlying IL-1beta-induced VCAM-1 expression in human tracheal smooth muscle cells (HTSMCs). Our results showed that IL-1beta enhanced HTSMCs-monocyte adhesion through up-regulation of VCAM-1, which was inhibited by pretreatment with selective inhibitors of PKCalpha (Gö6976), c-Src (PP1), NADPH oxidase [diphenylene iodonium (DPI) and apocynin (APO)], intracellular calcium chelator (BAPTA/AM), PI-PLC (U73122), CaM (calmidazolium chloride), CaM kinase II (KN62), p300 (garcinol), NF-kappaB (Bay11-7082), HDAC (trichostatin A), and ROS scavenger [N-acetyl-L-cysteine (NAC)] or transfection with siRNAs of MyD88, PKCalpha, Src, p47(phox), p300, and HDAC4. Moreover, IL-1beta stimulated NF-kappaB and CaMKII phosphorylation through MyD88-dependent PI-PLC/PKCalpha/c-Src/ROS and PI-PLC/Ca2+/CaM pathways, respectively. Activation of NF-kappaB and CaMKII may eventually lead to the acetylation of histone residues and phosphorylation of histone deacetylases. These findings suggested that IL-1beta induced VCAM-1 expression via these multiple signaling pathways in HTSMCs. Blockade of these pathways may reduce monocyte adhesion via VCAM-1 suppression and attenuation of the inflammatory responses in airway diseases. PMID:19281832

  6. Activation of ROS/NF-κB and Ca2+/CaM kinase II are necessary for VCAM-1 induction in IL-1β-treated human tracheal smooth muscle cells

    International Nuclear Information System (INIS)

    Histone acetylation regulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs) plays a critical role in the expression of inflammatory genes, such as vascular cell adhesion molecule-1 (VCAM-1). Oxidative processes have been shown to induce VCAM-1 expression. Here, we investigated the mechanisms underlying IL-1β-induced VCAM-1 expression in human tracheal smooth muscle cells (HTSMCs). Our results showed that IL-1β enhanced HTSMCs-monocyte adhesion through up-regulation of VCAM-1, which was inhibited by pretreatment with selective inhibitors of PKCα (Goe6976), c-Src (PP1), NADPH oxidase [diphenylene iodonium (DPI) and apocynin (APO)], intracellular calcium chelator (BAPTA/AM), PI-PLC (U73122), CaM (calmidazolium chloride), CaM kinase II (KN62), p300 (garcinol), NF-κB (Bay11-7082), HDAC (trichostatin A), and ROS scavenger [N-acetyl-L-cysteine (NAC)] or transfection with siRNAs of MyD88, PKCα, Src, p47phox, p300, and HDAC4. Moreover, IL-1β stimulated NF-κB and CaMKII phosphorylation through MyD88-dependent PI-PLC/PKCα/c-Src/ROS and PI-PLC/Ca2+/CaM pathways, respectively. Activation of NF-κB and CaMKII may eventually lead to the acetylation of histone residues and phosphorylation of histone deacetylases. These findings suggested that IL-1β induced VCAM-1 expression via these multiple signaling pathways in HTSMCs. Blockade of these pathways may reduce monocyte adhesion via VCAM-1 suppression and attenuation of the inflammatory responses in airway diseases.

  7. Hyperfine structure constants of the CaII states 4s2S1/2 and 4p2P1/2,3/2 and the nuclear quadrupole moment of 43Ca

    International Nuclear Information System (INIS)

    The hyperfine structure splittings of the 4s2S1/2→4p2P1/2,3/2 transitions in 43CaII have been measured by fast ion beam collinear laser spectroscopy. The resonant laser interaction was observed using non-optical detection based on optical ground state depopulation pumping, state selective neutralization and charge state separated particle counting. The extracted magnetic dipole hyperfine structure constants for 43Ca A(2S1/2)=-805(2) MHz, A(2P1/2)=-145.5(1.0) MHz and A(2P3/2)=-31.9(0.2) MHz are in excellent agreement with relativistic many body perturbation theory predictions available for this alkali-like ion. The combined results are used to evaluate the semi-empirical analysis method. From the electrical quadrupole hyperfine structure constant B(2P3/2)=-6.7(1.4) MHz and the calculated B/Q value for this one valance electron configuration, the nuclear quadrupole moment Q(43Ca)=-0.043(9)b is derived. This result supports a previous evaluation based on the hyperfine structure of the two valence electron 3P configurations of CaI. (orig.)

  8. Birth weight in a large series of triplets

    OpenAIRE

    van Beijsterveldt Catharina EM; Middeldorp Christel M; Lamb Diane J; Vink Jacqueline M; Haak Monique C; Boomsma Dorret I

    2011-01-01

    Abstract Background Triplets are often born premature and with a low birth weight. Because the incidence of triplet births is rare, there are relatively few studies describing triplet birth weight characteristics. Earlier studies are often characterized by small sample sizes and lack information on important background variables such as zygosity. The objective of this study is to examine factors associated with birth weight in a large, population-based sample of triplets registered with the N...

  9. Can the ''doublet-triplet splitting'' problem be solved without doublet-triplet splitting?

    International Nuclear Information System (INIS)

    We consider a new possible mechanism for the natural solution of the doublet-triplet splitting problem in SUSY GUTs. In contrast to the usually discussed scenarios, in our case the GUT symmetry breaking does not provide any splitting between the Higgs doublet and the triplet masses. The weak doublet and its colour triplet partner both remain light, but the triplet automatically occurs decoupled from the quark and lepton superfields and cannot induce proton decay. The advantage of the above scenarios is the absence at the GUT scale of the baryon number violating the tree level d = 5 and d = 6 operators via the colour-triple exchange. It is shown that in flipped SU(5) GUT they do not appear at any scale. In the SO(10) model, such operators can be induced after SUSY breaking but are strongly suppressed. (author). 22 refs, 2 figs

  10. An atlas of Calcium triplet spectra of active galaxies

    CERN Document Server

    Garcia-Rissmann, A; Asari, N V; Fernandes, R C; Schmitt, H; González-Delgado, R M; Storchi-Bergmann, T

    2005-01-01

    We present a spectroscopic atlas of active galactic nuclei covering the region around the 8498, 8542, 8662 Calcium triplet (CaT) lines. The sample comprises 78 objects, divided into 43 Seyfert 2s, 26 Seyfert 1s, 3 Starburst and 6 normal galaxies. The spectra pertain to the inner ~300 pc in radius, and thus sample the central kinematics and stellar populations of active galaxies. The data are used to measure stellar velocity dispersions (sigma_star) both with cross-correlation and direct fitting methods. These measurements are found to be in good agreement with each-other and with those in previous studies for objects in common. The CaT equivalent width is also measured. We find average values and sample dispersions of W_CaT of 4.6+/-2.0, 7.0 and 7.7+/-1.0 angstrons for Seyfert 1s, Seyfert 2s and normal galaxies, respectively. We further present an atlas of [SIII]\\lambda 9069 emission line profiles for a subset of 40 galaxies. These data are analyzed in a companion paper which addresses the connection between ...

  11. Birth weight in a large series of triplets

    NARCIS (Netherlands)

    D.J. Lamb; C.M. Middeldorp; C.E.M. van Beijsterveldt; J.M. Vink; M.C. Haak; D.I. Boomsma

    2011-01-01

    Background: Triplets are often born premature and with a low birth weight. Because the incidence of triplet births is rare, there are relatively few studies describing triplet birth weight characteristics. Earlier studies are often characterized by small sample sizes and lack information on importan

  12. Spontaneous Josephson spin current in triplet superconductor/ferromagnet/triplet superconductor junctions

    International Nuclear Information System (INIS)

    This paper theoretically studies Josephson spin current through triplet superconductor/ferromagnet/triplet superconductor junctions. At the ferromagnet/superconductor interfaces, the ferromagnetic scattering potential gives rise to coupling between the Andreev bound states and lifts their spin degeneracy. These spin-split Andreev states carry the Josephson spin current through the junctions. The generated spin supercurrent can be controlled by the magnetization of a ferromagnetic thin layer and bias voltage across the junctions. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  13. Influence of a mutation in the ATP-binding region of Ca2+/calmodulin-dependent protein kinase II on its interaction with peptide substrates.

    Science.gov (United States)

    Praseeda, Mullasseril; Pradeep, Kurup K; Krupa, Ananth; Krishna, S Sri; Leena, Suseela; Kumar, R Rajeev; Cheriyan, John; Mayadevi, Madhavan; Srinivasan, Narayanaswamy; Omkumar, Ramakrishnapillai V

    2004-03-01

    CaMKII (Ca2+/calmodulin-dependent protein kinase II) is expressed in high concentrations in the brain and is found enriched in the postsynaptic densities. The enzyme is activated by the binding of calmodulin to the autoregulatory domain in the presence of high levels of intracellular Ca2+, which causes removal of auto-inhibition from the N-terminal catalytic domain. Knowledge of the 3D (three-dimensional) structure of this enzyme at atomic resolution is restricted to the association domain, a region at the extreme C-terminus. The catalytic domain of CaMKII shares high sequence similarity with CaMKI. The 3D structure of the catalytic core of CaMKI comprises ATP- and substrate-binding regions in a cleft between two distinct lobes, similar to the structures of all protein kinases solved to date. Mutation of Glu-60, a residue in the ATP-binding region of CaMKII, to glycine exerts different effects on phosphorylation of two peptide substrates, syntide and NR2B ( N -methyl-D-aspartate receptor subunit 2B) 17-mer. Although the mutation caused increases in the Km values for phosphorylation for both the peptide substrates, the effect on the kcat values for each was different. The kcat value decreased in the case of syntide, whereas it increased in the case of the NR2B peptide as a result of the mutation. This resulted in a significant decrease in the apparent kcat/Km value for syntide, but the change was minimal for the NR2B peptide. These results indicate that different catalytic mechanisms are employed by the kinase for the two peptides. Molecular modelling suggests structural changes are likely to occur at the peptide-binding pocket in the active state of the enzyme as a consequence of the Glu-60-->Gly mutation. PMID:14558884

  14. Triplet excited state properties in variable gap π-conjugated donor–acceptor–donor chromophores

    KAUST Repository

    Cekli, Seda

    2016-02-12

    A series of variable band-gap donor–acceptor–donor (DAD) chromophores capped with platinum(II) acetylide units has been synthesized and fully characterized by electrochemical and photophysical methods, with particular emphasis placed on probing triplet excited state properties. A counter-intuitive trend of increasing fluorescence quantum efficiency and lifetime with decreasing excited state energy (optical gap) is observed across the series of DAD chromophores. Careful study of the excited state dynamics, including triplet yields (as inferred from singlet oxygen sensitization), reveals that the underlying origin of the unusual trend in the fluorescence parameters is that the singlet–triplet intersystem crossing rate and yield decrease with decreasing optical gap. It is concluded that the rate of intersystem crossing decreases as the LUMO is increasingly localized on the acceptor unit in the DAD chromophore, and this result is interpreted as arising because the extent of spin–orbit coupling induced by the platinum heavy metal centers decreases as the LUMO is more localized on the acceptor. In addition to the trend in intersystem crossing, the results show that the triplet decay rates follow the Energy Gap Law correlation over a 1.8 eV range of triplet energy and 1000-fold range of triplet decay rates. Finally, femtosecond transient absorption studies for the DAD chromophores reveals a strong absorption in the near-infrared region which is attributed to the singlet excited state. This spectral band appears to be general for DAD chromophores, and may be a signature of the charge transfer (CT) singlet excited state.

  15. Long-Lived Triplet Excited States of Bent-Shaped Pentacene Dimers by Intramolecular Singlet Fission.

    Science.gov (United States)

    Sakuma, Takao; Sakai, Hayato; Araki, Yasuyuki; Mori, Tadashi; Wada, Takehiko; Tkachenko, Nikolai V; Hasobe, Taku

    2016-03-24

    Intramolecular singlet fission (ISF) is a promising photophysical process to construct more efficient light energy conversion systems as one excited singlet state converts into two excited triplet states. Herein we synthesized and evaluated bent-shaped pentacene dimers as a prototype of ISF to reveal intrinsic characters of triplet states (e.g., lifetimes of triplet excited states). In this study, meta-phenylene-bridged TIPS-pentacene dimer (PcD-3Ph) and 2,2'-bipheynyl bridged TIPS-pentacene dimer (PcD-Biph) were newly synthesized as bent-shaped dimers. In the steady-state spectroscopy, absorption and emission bands of these dimers were fully characterized, suggesting the appropriate degree of electronic coupling between pentacene moieties in these dimers. In addition, the electrochemical measurements were also performed to check the electronic interaction between two pentacene moieties. Whereas the successive two oxidation peaks owing to the delocalization were observed in a directly linked-pentacene dimer (PcD) by a single bond, the cyclic voltammograms in PcD-Biph and PcD-3Ph implied the weaker interaction compared to that of p-phenylene-bridged TIPS-pentacene dimer (PcD-4Ph) and PcD. The femtosecond and nanosecond transient absorption spectra clearly revealed the slower ISF process in bent-shaped pentacene dimers (PcD-Biph and PcD-3Ph), more notably, the slower relaxation of the excited triplet states in PcD-Biph and PcD-3Ph. Namely, the quantum yields of triplet states (ΦT) by ISF approximately remain constant (ca. 180-200%) in all dimer systems, whereas the lifetimes of the triplet excited states became much longer (up to 360 ns) in PcD-Biph as compared to PcD-4Ph (15 ns). Additionally, the lifetimes of the corresponding triplet states in PcD-Biph and PcD-3Ph were sufficiently affected by solvent viscosity. In particular, the lifetimes of PcD-Biph triplet state in THF/paraffin (1.0 μs) increased up to approximately three times as compared to that in THF

  16. The Predicted Spectrum and Singlet-Triplet Interaction of the Hypermetallic Molecule SrOSr

    Science.gov (United States)

    Ostojić, B.; Jensen, Per; Schwerdtfeger, P.; Bunker, P. R.

    2013-10-01

    In accordance with previous studies in our group on Be, Mg, and Ca hypermetallic oxides, we find that SrOSr has a linear X-1Σg+ ground electronic state and a very low lying first excited -3Σu+ triplet electronic state. No gas-phase spectrum of this molecule has been assigned yet, and to encourage and assist in its discovery we present a complete ab initio simulation, with absolute intensities, of the infrared absorption spectrum for both electronic states. The three-dimensional potential energy surfaces and the electric dipole moment surfaces of the X-1Σg+ and -3Σu+ electronic states are calculated using a multireference configuration interaction (MRCISD) approach in combination with internally contracted multireference perturbation theory (RS2C) based on complete active space self-consistent field (CASSCF) wave functions applying a Sadlej pVTZ basis set for both O and Sr and the Stuttgart relativistic small-core effective core potential for Sr. The infrared spectra are simulated using the MORBID program system. We also calculate vertical excitation energies and transition moments for several excited singlet and triplet electronic states in order to predict the positions and intensities of the most prominent singlet and triplet electronic absorption bands. Finally, for this heavy molecule, we calculate the singlet-triplet interaction matrix elements between close-lying vibronic levels of the X- and - electronic states and find them to be very small.

  17. Synthesis and Exciton Dynamics of Triplet Sensitized Conjugated Polymers

    KAUST Repository

    Andernach, Rolf

    2015-07-22

    We report the synthesis of a novel polythiophene-based host-guest copolymer incorporating a Pt-porphyrin complex (TTP-Pt) into the backbone for efficient singlet to triplet polymer exciton sensitization. We elucidated the exciton dynamics in thin films of the material by means of Transient Absorption Spectrosopcy (TAS) on multiple timescales and investigated the mechanism of triplet exciton formation. During sensitization, single exciton diffusion is followed by exciton transfer from the polymer backbone to the complex where it undergoes intersystem crossing to the triplet state of the complex. We directly monitored the triplet exciton back transfer from the Pt-porphyrin to the polymer and find that 60% of the complex triplet excitons are transferred with a time constant of 1087 ps. We propose an equilibrium between polymer and porphyrin triplet states as a result of the low triplet diffusion length in the polymer backbone and hence an increased local triplet population resulting in increased triplet-triplet annihilation. This novel system has significant implications for the design of novel materials for triplet sensitized solar cells and up-conversion layers.

  18. A comparative study of caffeine and theophylline binding to Mg(II) and Ca(II) ions: studied by FTIR and UV spectroscopic methods

    Science.gov (United States)

    Nafisi, Shohreh; Shamloo, Delaram Sadraii; Mohajerani, Nasser; Omidi, Akram

    2002-08-01

    The interactions of calcium and magnesium ions with caffeine and theophylline have been investigated in aqueous solution at physiological pH. Fourier Transform infrared (FTIR) spectroscopy and absorption spectra were used to determine the cation binding mode and the association constants. Our spectroscopic results showed that calcium and magnesium ions do not complex with caffeine strongly and the weak interactions between caffeine and Mg 2+ and Ca 2+ might be via O6 atom. In Ca 2+-theophylline complex, binding between Ca 2+ with CO and N7 is observed, however in Mg 2+-theophylline complex, binding between Mg 2+ and N7 is more likely. The k values of these complexes are as follows: k(caffeine-Ca)=29.8 M -1, k(caffeine-Mg)=22.4 M -1, k(theophylline-Ca)=59.8 M -1 and k(theophylline-Mg)=33.8 M -1. These values are evidence for a weak cation interaction in these metal complexes.

  19. Nonextensive triplet in geological faults system

    CERN Document Server

    de Freitas, D B; Scheerer, T M; Vilar, C S; Silva, R

    2013-01-01

    The San Andreas fault (SAF) in the USA is one of the most investigated self-organizing systems in nature. In this paper, we studied some geophysical properties of the SAF system in order to analyze the behavior of earthquakes in the context of Tsallis's $q$--Triplet. To that end, we considered 134,573 earthquake events in magnitude interval $2\\leq m<8$, taken from the Southern Earthquake Data Center (SCEDC, 1932 - 2012). The values obtained ("$q$--Triplet"$\\equiv$$\\{$$q$$_{stat}$,$q$$_{sen}$,$q$$_{rel}$$\\}$) reveal that the $q_{stat}$--Gaussian behavior of the aforementioned data exhibit long-range temporal correlations. Moreover, $q_{sen}$ exhibits quasi-monofractal behavior with a Hurst exponent of 0.87.

  20. Triplet Higgs boson at hadron colliders

    International Nuclear Information System (INIS)

    The novel feature of a Higgs-triplet representation is a nonzero tree-level coupling of H+W-Z, which is absent in all Higgs-doublet models. We study the associated production of a singly-charged Higgs boson of the Higgs-triplet representation with a W or Z boson at hadron colliders, followed by the H+→W+Z decay. We find that the 2l+4j final state gives an interesting level of signal with a negligible background, plus it allows a full mass reconstruction of the charged-Higgs boson. The cover range of the charged-Higgs mass is between 110 and 200 GeV. (author)

  1. Electrochemical detection of DNA triplet repeat expansion

    Czech Academy of Sciences Publication Activity Database

    Fojta, Miroslav; Havran, Luděk; Vojtíšková, Marie; Paleček, Emil

    2004-01-01

    Roč. 126, č. 21 (2004), s. 6532-6533. ISSN 0002-7863 R&D Projects: GA AV ČR IAA4004402; GA AV ČR IBS5004355; GA AV ČR KJB4004302; GA AV ČR KSK4055109 Institutional research plan: CEZ:AV0Z5004920 Keywords : DNA triplet repeat expansion * PCR amplification * neurodegenerative diseases Subject RIV: BO - Biophysics Impact factor: 6.903, year: 2004

  2. Involvement of Ca2+/calmodulin-dependent protein kinase II in the activation of carnitine palmitoyltransferase I by okadaic acid in rat hepatocytes.

    Science.gov (United States)

    Velasco, G; Guzmán, M; Zammit, V A; Geelen, M J

    1997-01-01

    The present work was undertaken to study the mechanism by which okadaic acid (OA), an inhibitor of protein phosphatases 1 and 2A, stimulates carnitine palmitoyltransferase I (CPT-I) in isolated rat hepatocytes [Guzmán, Kolodziej, Caldwell, Costorphine and Zammit (1994) Biochem. J. 300, 693-699]. The OA-induced stimulation of CPT-I was abolished by the general protein kinase inhibitor K-252a as well as by KN-62, a specific inhibitor of Ca2+/calmodulin-dependent protein kinase II (Ca2+/CM-PKII). However, neither the protein kinase C-specific inhibitor bisindolylmaleimide nor the protein kinase A/protein kinase C inhibitor H-7 was able to prevent the OA-induced stimulation of CPT-I. Hepatocyte-shrinkage-induced stimulation of CPT-I as well as OA-induced hepatocyte shrinkage was prevented by KN-62. KN-62 also antagonized the OA-enhanced release of lactate dehydrogenase from digitonin-permeabilized hepatocytes. Exposure of 32P-labelled hepatocytes to OA increased the degree of phosphorylation of Ca2+/CM-PKII, as immunoprecipitated by a monoclonal antibody raised against the alpha-subunit of rat brain kinase. This effect of OA was also antagonized by KN-62. The results thus indicate that the OA-dependent stimulation of CPT-I may be mediated (at least in part) by increased phosphorylation and subsequent activation of Ca2+/CM-PKII. PMID:9003421

  3. Beam dynamics in magnetic quadrupole triplets

    International Nuclear Information System (INIS)

    The Frankfurt Neutron source at the Stern-Gerlach-Zentrum (FRANZ) will produce high intensity neutron pulses in the energy range of 1 to 500 keV at a very short repetition rate. The neutrons are gained from 7Li(p,n)7Be reactions induced by 2 MeV protons and will be used to examine the nucleosynthesis during the s-process as it occurs in stars, cross sections of neutron capture reactions as well as the behaviour of non-neutral plasmas. In the linear accelerator section, consisting of a 4-rod-radio-frequency-quadrupole and a H-type drift tube linac, the proton pulses are accelerated to 2.03 MeV. Inside the drift tube cavity a magnetic quadrupole triplet will be integrated, in order to compensate transversally defocussing effects and therefore avoid losses. Behind the linear accelerator section the proton beam ist rebunched in a 5-cell CH-rebuncher which is framed by two more quadrupole triplets. To investigate the beam dynamics inside the magnetic quadrupole triplets, various magnetostatic and particle tracking codes like CST Studio and LORASR were used to simulate the beam transport properties of the magnets and compare the individual magnetic field distributions with the ones measured at the magnet laboratory at GSI. In doing so, important aspects to be considered are the longitudinal and transversal fringe fields and the saturation effects which all possibly cause emittance growth and geometrical aberrations.

  4. Beam dynamics in magnetic quadrupole triplets

    Energy Technology Data Exchange (ETDEWEB)

    Claessens, Christine; Heilmann, Manuel; Meusel, Oliver; Podlech, Holger; Ratzinger, Ulrich; Wiesner, Christoph [IAP, Frankfurt University, Frankfurt am Main (Germany)

    2013-07-01

    The Frankfurt Neutron source at the Stern-Gerlach-Zentrum (FRANZ) will produce high intensity neutron pulses in the energy range of 1 to 500 keV at a very short repetition rate. The neutrons are gained from {sup 7}Li(p,n){sup 7}Be reactions induced by 2 MeV protons and will be used to examine the nucleosynthesis during the s-process as it occurs in stars, cross sections of neutron capture reactions as well as the behaviour of non-neutral plasmas. In the linear accelerator section, consisting of a 4-rod-radio-frequency-quadrupole and a H-type drift tube linac, the proton pulses are accelerated to 2.03 MeV. Inside the drift tube cavity a magnetic quadrupole triplet will be integrated, in order to compensate transversally defocussing effects and therefore avoid losses. Behind the linear accelerator section the proton beam ist rebunched in a 5-cell CH-rebuncher which is framed by two more quadrupole triplets. To investigate the beam dynamics inside the magnetic quadrupole triplets, various magnetostatic and particle tracking codes like CST Studio and LORASR were used to simulate the beam transport properties of the magnets and compare the individual magnetic field distributions with the ones measured at the magnet laboratory at GSI. In doing so, important aspects to be considered are the longitudinal and transversal fringe fields and the saturation effects which all possibly cause emittance growth and geometrical aberrations.

  5. Photoprotection and triplet energy transfer in higher plants: the role of electronic and nuclear fluctuations.

    Science.gov (United States)

    Cupellini, Lorenzo; Jurinovich, Sandro; Prandi, Ingrid G; Caprasecca, Stefano; Mennucci, Benedetta

    2016-04-20

    Photosynthetic organisms employ several photoprotection strategies to avoid damage due to the excess energy in high light conditions. Among these, quenching of triplet chlorophylls by neighboring carotenoids (Cars) is fundamental in preventing the formation of singlet oxygen. Cars are able to accept the triplets from chlorophylls by triplet energy transfer (TET). We have here studied TET rates in CP29, a minor light-harvesting complex (LHC) of the Photosystem II in plants. A fully atomistic strategy combining classical molecular dynamics of the LHC in its natural environment with a hybrid time-dependent density functional theory/polarizable MM description of the TET is used. We find that the structural fluctuations of the pigment-protein complex can largely enhance the transfer rates with respect to those predicted using the crystal structure, reducing the triplet quenching times in the subnanosecond scale. These findings add a new perspective for the interpretation of the photoprotection function and its relation with structural motions of the LHC. PMID:27052105

  6. Ca II absorption lines in the spectrum of the quasar pks 2020--370 due to galactic material in the group Klemola 31

    International Nuclear Information System (INIS)

    In the spectrum of the quasar PKs 2020--370 (z/sub em/ = 1.050), we find Ca II absorption lines both at near zero redshift and at z/sub abs/ = 0.02865 +- 0.00007. The latter is closely similar to the redshifts of two galaxies in the group Klemola 31, which are nearby on the plane of the sky. This observation adds to the evidence that the narrow-lined heavy-element absorption systems in quasar spectra in general arise in the extended halos of intervening galaxies

  7. (41)Ca in Tooth Enamel. Part II: A means for retrospective biological neutron dosimetry in atomic bomb survivors.

    Science.gov (United States)

    Rühm, W; Wallner, A; Cullings, H; Egbert, S D; El-Faramawy, N; Faestermann, T; Kaul, D; Knie, K; Korschinek, G; Nakamura, N; Roberts, J; Rugel, G

    2010-08-01

    (41)Ca is produced mainly by absorption of low-energy neutrons on stable (40)Ca. We used accelerator mass spectrometry (AMS) to measure (41)Ca in enamel of 16 teeth from 13 atomic bomb survivors who were exposed to the bomb within 1.2 km from the hypocenter in Hiroshima. In our accompanying paper (Wallner et al., Radiat. Res. 174, 000-000, 2010), we reported that the background-corrected (41)Ca/Ca ratio decreased from 19.5 x 10(-15) to 2.8 x 10(-15) with increasing distance from the hypocenter. Here we show that the measured ratios are in good correlation with gamma-ray doses assessed by electron paramagnetic resonance (EPR) in the same enamel samples, and agree well with calculated ratios based on either the current Dosimetry System 2002 (DS02) or more customized dose estimates where the regression slope as obtained from an errors-in-variables linear model was about 0.85. The calculated DS02 neutron dose to the survivors was about 10 to 80 mGy. The low-energy neutrons responsible for (41)Ca activation contributed variably to the total neutron dose depending on the shielding conditions. Namely, the contribution was smaller (10%) when shielding conditions were lighter (e.g., outside far away from a single house) and was larger (26%) when they were heavier (e.g., in or close to several houses) because of local moderation of neutrons by shielding materials. We conclude that AMS is useful for verifying calculated neutron doses under mixed exposure conditions with gamma rays. PMID:20681781

  8. Intra-Inter Triplet Object Interaction Mechanism in Triplet-Based Hierarchical Interconnection Network

    Directory of Open Access Journals (Sweden)

    Shahnawaz Talpur

    2013-07-01

    Full Text Available Object oriented languages usually avoid direct message passing, due to its complicated implementation, though that is the promising way to communicate in concurrently inherited objects. With the advancement in the high performance computing system, interaction between parallel application objects onto physical cores becomes one of the significant issues, which is not fully explored yet. In object oriented programming attribute data is included in objects and their state can be changed using the methods. Objects enable massage passing to other objects interacting with each other. Comprehensive problems can be molded by object-oriented methodology, and solves difficult program running object-oriented programs.Cores communicate with each other through communicator and groups in MPI, but in our reference architecture TBHIN (Triplet Based Hierarchical Interconnection Network, the cores are already faction in Triplets. We propose IITOIM Model to improve the performance with efficient intra-inter triplet cores communication mechanism between the objects in TBHIN

  9. Minimal type II seesaw model

    International Nuclear Information System (INIS)

    We propose a minimal type II seesaw model by introducing only one right-handed neutrino besides the SU(2)L triplet Higgs to the standard model. In the usual type II seesaw models with several right-handed neutrinos, the contributions of the right-handed neutrinos and the triplet Higgs to the CP asymmetry, which stems from the decay of the lightest right-handed neutrino, are proportional to their respective contributions to the light neutrino mass matrix. However, in our minimal type II seesaw model, this CP asymmetry is just given by the one-loop vertex correction involving the triplet Higgs, even though the contribution of the triplet Higgs does not dominate the light neutrino masses. For illustration, the Fritzsch-type lepton mass matrices are considered

  10. Direct observation of triplet energy transfer from semiconductor nanocrystals.

    Science.gov (United States)

    Mongin, Cédric; Garakyaraghi, Sofia; Razgoniaeva, Natalia; Zamkov, Mikhail; Castellano, Felix N

    2016-01-22

    Triplet excitons are pervasive in both organic and inorganic semiconductors but generally remain confined to the material in which they originate. We demonstrated by transient absorption spectroscopy that cadmium selenide semiconductor nanoparticles, selectively excited by green light, engage in interfacial Dexter-like triplet-triplet energy transfer with surface-anchored polyaromatic carboxylic acid acceptors, extending the excited-state lifetime by six orders of magnitude. Net triplet energy transfer also occurs from surface acceptors to freely diffusing molecular solutes, further extending the lifetime while sensitizing singlet oxygen in an aerated solution. The successful translation of triplet excitons from semiconductor nanoparticles to the bulk solution implies that such materials are generally effective surrogates for molecular triplets. The nanoparticles could thereby potentially sensitize a range of chemical transformations that are relevant for fields as diverse as optoelectronics, solar energy conversion, and photobiology. PMID:26798011

  11. Lepton Flavor Violation in the singlet-triplet scotogenic model

    OpenAIRE

    Rocha-Moran, Paulina; Vicente, Avelino

    2016-01-01

    We investigate lepton flavor violation (LFV) in the the singlet-triplet scotogenic model in which neutrinos acquire non-zero masses at the 1-loop level. In contrast to the most popular variant of this setup, the singlet scotogenic model, this version includes a triplet fermion as well as a triplet scalar, leading to a scenario with a richer dark matter phenomenology. Taking into account results from neutrino oscillation experiments, we explore some aspects of the LFV phenomenology of the mode...

  12. VizieR Online Data Catalog: Spectroscopy at the solar limb. I. Average off-limb profiles and Doppler shifts of Ca II H.

    Science.gov (United States)

    Beck, C.; Rezaei, R.

    2011-10-01

    The data used in the publication consist of a set of CaII H spectra taken near and beyond the solar limb on 25/08/2009 at UT 08:43-09:15. The data were obtained with the POLIS instrument at the German VTT. The wavelength range covers the core and the blue wing of the CaII H line from 396.332nm to 396.969nm in 326 steps of 1.96pm. The observations were done by moving the solar image across the slit of the spectrograph with a step width of 0.3-arcsec, yielding in total 134 slit spectra of 326 wavelength points on 244 CCD rows along the slit. The spatial sampling along the slit was 0.3-arcsec. The center of the field-of-view was located at (x,y)=(+37",+920") relative to the center of the solar disk. The data have been corrected for stray-light with the methods described in the article and are normalized to the continuum intensity on disc center. The corresponding data file data.fit is organized as floating array (x,y,wavelength)=(134x244x326) pixels. (1 data file).

  13. Toward Triplet Ground State NaLi Molecules

    Science.gov (United States)

    Ebadi, Sepehr; Jamison, Alan; Rvachov, Timur; Jing, Li; Son, Hyungmok; Jiang, Yijun; Zwierlein, Martin; Ketterle, Wolfgang

    2016-05-01

    The NaLi molecule is expected to have a long lifetime in the triplet ground-state due to its fermionic nature, large rotational constant, and weak spin-orbit coupling. The triplet state has both electric and magnetic dipole moments, affording unique opportunities in quantum simulation and ultracold chemistry. We have mapped the excited state NaLi triplet potential by means of photoassociation spectroscopy. We report on this and our further progress toward the creation of the triplet ground-state molecules using STIRAP. NSF, ARO-MURI, Samsung, NSERC.

  14. Powering the High-Luminosity Triplets

    CERN Document Server

    Ballarino, A

    2015-01-01

    The powering of the magnets in the LHC High-Luminosity Triplets requires production and transfer of more than 150 kA of DC current. High precision power converters will be adopted, and novel High Temperature Superconducting (HTS) current leads and MgB2 based transfer lines will provide the electrical link between the power converters and the magnets. This chapter gives an overview of the systems conceived in the framework of the LHC High-Luminosity upgrade for feeding the superconducting magnet circuits. The focus is on requirements, challenges and novel developments.

  15. Structural basis for triplet repeat disorders

    DEFF Research Database (Denmark)

    Baldi, Pierre; Brunak, Søren; Chauvin, Yves; Pedersen, Anders Gorm

    1999-01-01

    ? Results: Using several different computational models of DNA structure, we show that the triplets involved in the pathological repeats generally fall into extreme classes. Thus, CAG/CTG repeats are particularly flexible, whereas GCC, CGG and GAA repeats appear to display both flexible and rigid (but...... curved) characteristics depending on the method of analysis. The fact that (1) trinucleotide repents often become increasingly unstable when they exceed a length of approximately 50 repeats, and (2) repented 12-mers display a similar increase in instability above 13 repeats, together suggest that......, which we predict to have very high flexibility, may play a role in the pathogenesis of the neurodegenerative disorder multiple system atrophy (MSA)....

  16. Cation exchanged Fe(II) and Sr compared to other divalent cations (Ca, Mg) in the bure Callovian-Oxfordian formation: Implications for porewater composition modelling

    International Nuclear Information System (INIS)

    thermodynamic databases seems to be far more appropriate. Concerning Fe(II) and siderite/ankerite equilibrium, the measured Fe/Ca ratio on the clay exchanger (∼0.01) could only be considered as a maximum value due to possible experimental bias, leading to the following constraint for the solubility of the sideroplesite phase present in the COX: Fe0.7Mg0.2Ca0.1CO3 + H+↔ 0.7 Fe2+ + 0.2 Mg2+ + 0.1 Ca2+ + HCO3-logKsidCOX sidCOX = 0.23

  17. A new medium for triplet-triplet annihilated upconversion and photocatalytic application.

    Science.gov (United States)

    Ye, Changqing; Wang, Jingjing; Wang, Xiaomei; Ding, Ping; Liang, Zuoqin; Tao, Xutang

    2016-02-01

    Since the triplet-triplet annihilated upconversion (TTA-UC) materials work efficiently only in degassing organic solvents, it is of significance to find a new medium without toxicity and volatility and that promotes TTA-UC. Here, we firstly reported the effect of an OH-containing medium on low power upconversion and found that in alcohol solvent containing β-cyclodextrin (β-CD), the phosphorescence lifetime (τp) of the sensitizer (PdTPP) and the fluorescence quantum yield (Φf) of the acceptor (DPA) were enhanced with the increase in the number of OH-groups of the medium. A large triplet-triplet quenching constant (kq, 1.91 × 10(9) M(-1) s(-1)) and high upconversion efficiency (ΦUC, ∼ 36%) of PdTPP/DPA were obtained under the excitation of a diode laser (532 nm, 60 mW cm(-2)). Under our green-to-blue upconversion irradiation, in a demonstration experiment the photocurrent was recorded at 0.09 μA cm(-2), resulting from photocatalytic water splitting by a Cd0.7Zn0.3S photoanode and a Pt counter-electrode in a photoelectrochemical cell. The importance of this study suggests that upconversion-powered photoelectrochemistry possesses potential application for hydrogen generation from water under excitation of sun energy. PMID:26580451

  18. Extraction of Ca (II) and Mg (II) from Hydrochloric Acid Solutions by N, N-Dioctyl-1-Octan Ammonium Chloride in Methyl Isobutyl Ketone

    OpenAIRE

    Fatmir Faiku; Arben Haziri; Imer Haziri; Sali Aliu; Nita Sopa

    2012-01-01

    Problem statement: Amines as organic molecules are able to form complexes with metals ions and this is the reason why we can use them to extract metals ions from hydrometallurgical solutions. Approach: Based on that, we have investigated the extraction of Calcium and Magnesium with N, N-dioctyl-1-octan ammonium chloride from the mixture of elements (Ca and Mg) prepared in artificial manner. We have investigated the influence of HCl concentration and salts (NaCl, NaI and CH3COONa) concentratio...

  19. Triplet-Triplet Annihilation Photon Upconversion in Polymer Thin Film: Sensitizer Design.

    Science.gov (United States)

    Jiang, Xinpeng; Guo, Xinyan; Peng, Jiang; Zhao, Dahui; Ma, Yuguo

    2016-05-11

    Efficient visible-to-UV photon upconversion via triplet-triplet annihilation (TTA) is accomplished in polyurethane (PU) films by developing new, powerful photosensitizers fully functional in the solid-state matrix. These rationally designed triplet sensitizers feature a bichromophoric scaffold comprising a tris-cyclometalated iridium(III) complex covalently tethered to a suitable organic small molecule. The very rapid intramolecular triplet energy transfer from the former to the latter is pivotal for achieving the potent sensitizing ability, because this process out-competes the radiative and nonradiative decays inherent to the metal complex and produces long-lived triplet excitons localized with the acceptor moiety readily available for intermolecular transfer and TTA. Nonetheless, compared to the solution state, the molecular diffusion is greatly limited in solid matrices, which even creates difficulty for the Dexter-type intramolecular energy transfer. This is proven by the experimental results showing that the sensitizing performance of the bichromophoric molecules strongly depends on the spatial distance separating the donor (D) and acceptor (A) units and that incorporating a longer linker between the D and A evidently curbs the TTA upconversion efficiency in PU films. Using a rationally optimized sensitizer structure in combination with 2,7-di-tert-butylpyrene as the annihilator/emitter, the doped polyurethane (PU) films demonstrate effective visible-to-UV upconverted emission signal under noncoherent-light irradiation, attaining an upconversion quantum yield of 2.6%. Such quantum efficiency is the highest value so far reported for the visible-to-UV TTA systems in solid matrices. PMID:27082767

  20. Extraction of Ca (II and Mg (II from Hydrochloric Acid Solutions by N, N-Dioctyl-1-Octan Ammonium Chloride in Methyl Isobutyl Ketone

    Directory of Open Access Journals (Sweden)

    Fatmir Faiku

    2012-01-01

    Full Text Available Problem statement: Amines as organic molecules are able to form complexes with metals ions and this is the reason why we can use them to extract metals ions from hydrometallurgical solutions. Approach: Based on that, we have investigated the extraction of Calcium and Magnesium with N, N-dioctyl-1-octan ammonium chloride from the mixture of elements (Ca and Mg prepared in artificial manner. We have investigated the influence of HCl concentration and salts (NaCl, NaI and CH3COONa concentration in extraction of two elements (Ca and Mg from water solutions. All extractions were done from HCl water solutions with c = 3, 6 and 9 mol L-1 and in presence of NaCl, NaI and CH3COONa salts, which we prepared in different concentrations. Results: Extraction of Calcium from NaCl solution move from 18-30%, from NaI solution 55-77% and from CH3COONa solution 50-71%. Extraction of Magnesium from NaCl solution move from 3-12%, from NaI solution 0-11% and from CH3COONa solution 0-8%. Conclusion: As optimal condition to separate Calcium from Magnesium is the extraction of Calcium from HCl solution with concentration 9 mol L-1 in presence of NaI with concentration of 60 g L-1. Using these condition 77% of Calcium was in organic phase and all of magnesium remains in water phase.

  1. The superconducting spin valve and triplet superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Garifullin, I.A., E-mail: ilgiz_garifullin@yahoo.com [Zavoisky Physical-Technical Institute, Kazan Scientific Center of Russian Academy of Sciences, 420029 Kazan (Russian Federation); Leksin, P.V.; Garif' yanov, N.N.; Kamashev, A.A. [Zavoisky Physical-Technical Institute, Kazan Scientific Center of Russian Academy of Sciences, 420029 Kazan (Russian Federation); Fominov, Ya.V. [L. D. Landau Institute for Theoretical Physics RAS, 119334 Moscow (Russian Federation); Moscow Institute of Physics and Technology, 141700 Dolgoprudny (Russian Federation); Schumann, J.; Krupskaya, Y.; Kataev, V.; Schmidt, O.G. [Leibniz Institute for Solid State and Materials Research IFW Dresden, D-01171 Dresden (Germany); Büchner, B. [Leibniz Institute for Solid State and Materials Research IFW Dresden, D-01171 Dresden (Germany); Institut für Festkörperphysik, Technische Universität Dresden, D-01062 Dresden (Germany)

    2015-01-01

    A review of our recent results on the spin valve effect is presented. We have used a theoretically proposed spin switch design F1/F2/S comprising a ferromagnetic bilayer (F1/F2) as a ferromagnetic component, and an ordinary superconductor (S) as the second interface component. Based on it we have prepared and studied in detail a set of multilayers CoO{sub x}/Fe1/Cu/Fe2/S (S=In or Pb). In these heterostructures we have realized for the first time a full spin switch effect for the superconducting current, have observed its sign-changing oscillating behavior as a function of the Fe2-layer thickness and finally have obtained direct evidence for the long-range triplet superconductivity arising due to noncollinearity of the magnetizations of the Fe1 and Fe2 layers. - Highlights: • We studied a spin switch design F1/F2/S. • We prepared a set of multilayers CoOx/Fe1/Cu/Fe2/S (S=In or Pb). • The full spin switch effect for the superconducting current was realized. • We observed its oscillating behavior as a function of the Fe2-layer thickness. • We obtained direct evidence for the long-range triplet superconductivity.

  2. Tetralogy of Fallot in monozygotic triplets

    Energy Technology Data Exchange (ETDEWEB)

    Victorica, B.E.; Kumar, A.; Zori, R.T. [Univ. of Florida, Gainesville, FL (United States)

    1994-09-01

    Tetralogy of Fallot (TOF), like most other congenital heart defects, is considered to be of multifactorial inheritance. Occasional families with multiple affected members in one or more generations above been described. A stronger genetic influence in the causation of isolated TOF is also supported by recent demonstration of microdeletions in chromosome 22q11 region. Deletions in this region are also responsible for DiGeorge and velocardiofacial syndrome as well as CHARGE association. We report a set of monozygotic triplets born to healthy parents at 35 weeks of gestation. There was no family history of congenital heart defects. All three had TOF with left aortic arch (documented by cardiac catheterization in 2 and echocardiography in all 3). The degree of right ventricular outflow obstruction varied from mild to complete atresia needing prostaglandin infusion and a subsequent Blalock-Taussig shunt in one. No features of DiGeorge syndrome or any other congenital defects were present. High resolution chromosome analysis of peripheral blood lymphocytes of these infants revealed normal 46,XY male karyotype. Fluorescent in situ hybridization (FISH) using probe D22S75, which maps to chromosome 22q11.2 did not detect any deletion. This pedigree suggests a de novo mutation causing TOF in all 3 monozygotic triplets. Although there is no deletion demonstrable in DiGeorge critical region, a smaller deletion or mutation in this region cannot be excluded.

  3. Heavy Vector Triplets: Bridging Theory and Data

    CERN Document Server

    Pappadopulo, Duccio; Torre, Riccardo; Wulzer, Andrea

    2014-01-01

    We introduce a model-independent strategy to study narrow resonances which we apply to a heavy vector triplet of the Standard Model (SM) group for illustration. The method is based on a simplified phenomenological Lagrangian which reproduces a large class of explicit models. Firstly, this allows us to derive robust model-independent phenomenological features and, conversely, to identify the peculiarities of different explicit realizations. Secondly, limits on cross-section times BR can be converted into bounds on a few relevant parameters in a fully analytic way, allowing for an interpretation in any given explicit model. Based on the available 8 TeV LHC analyses, we derive current limits and interpret them for vector triplets arising in weakly coupled (gauge) and strongly coupled (composite) extensions of the SM. We point out that a model-independent limit setting procedure must be based on purely on-shell quantities, like a cross-section times BR. Finite width effects altering the limits can be considerably...

  4. The neonatal outcome in twin versus triplet and quadruplet pregnancies

    Directory of Open Access Journals (Sweden)

    Fatemeh Nasseri

    2009-02-01

    Full Text Available

    • BACKGROUND: To assess the risk of neonatal mortality and morbidity in twin, triplet and quadruplet pregnancies.
    • METHODS: In a retrospective study, the neonatal outcome of all twin, triplet and quadruplet gestations delivered from October 2001 to September 2006 was reviewed. The neonatal outcome of triples and quadruplets was compared with a matched group of twins for gestational age.
    • RESULTS: During a 5-year period, 511 sets of twin pregnancies, 42 sets of triplet and 5 sets of quadruplet pregnancies were studied. The mean of gestational age for twins, triplets and quadruplets were 33.92 ± 3.5 weeks, 30.92 ± 3.8 weeks and 31.60 ± 2.0 weeks, respectively, (P = 0.0001. Triplets and quadruplets weighed less than twins, (P = 0.0001. Neonatal mortality was 13.5% for twins, 26.8% for triplets and 30% for quadruplets. In vitro fertilization, use of ovulation induction agents, and cesarean delivery in the women with triplet and quadruplet were significantly higher than in those with twin pregnancies, (P = 0.0001. The mean age of mothers with triplets and quadruplets was significantly higher than with twins (P = 0.026. There was not a significant difference in respiratory and non-respiratory short outcomes between triplets, quadruplets and twins when matched for gestational age. Apgar score at 1 and 5 minutes was significantly lower in triplets and quadruplets than twins. There was no influence of birth order on neonatal mortality of triplet pregnancy. Neonatal mortality of triplet births was significantly decreased over the 5 years of the study period.
    • CONCLUSIONS: Triplets and quadruplets have a similar neonatal outcome as twins when matched for gestational age. There is no influence of birth on the neonatal mortality of triplet pregnancy. It appears that outcome is mainly dependent on gestational age.
    • KEYWORDS: Neonatal

    • (Cu,Tl)Ba2Ca3Cu4Ox compositions: II. Heating rate applied to synthesis of superconducting ceramics

      International Nuclear Information System (INIS)

      Superconducting samples with a starting composition Cu0.5TlxBa2Ca3Cu4O12 (x=1-0.35) were prepared in Au tubes from oxides by using different heating rates. The optimum heating rate was 0.11 deg. C min-1 applied between 860 and 880 deg. C. These samples show the highest content of 1234 phase and the lowest of Ba-Cu-O phases as well as the highest critical temperatures. The highest values were Tc=119.2 K and Tc0=115.1 K. All samples show Jc values around 6x105 A cm-2, at 60 K and 0.5 T. In the rest of the samples, heated by using lower or higher heating rates, a high concentration of 1223 and/or 1245 phases is detected. The content of the 1234 phase and of Ba(Ca,Tl)-Cu-O residual liquid phase, in the samples synthesized for the optimum heating rate, depends on the Tl content in the starting mixture. The influence of the oxygen content in the starting mixture on phase composition is not as strong as of Tl, but it has a major role in establishing the superconducting behaviour of the 1234 grains. Some arguments that suggest the dependence of the transport properties of the non-superconducting matrix on oxygen content will be discussed. In our technological arrangement the determined optimum heating rate can be applied to the synthesis of other single-layered superconducting phases, e.g. 1212 phase from a Cu0.25Tl0.75Ba2CaCu2O8.115 starting composition. (author)

    • Fusion pore expansion is a slow, discontinuous, and Ca2+ -dependent process regulating secretion from alveolar type II cells

      OpenAIRE

      Haller, Thomas; Dietl, Paul; Pfaller, Kristian; Frick, Manfred; Mair, Norbert; Paulmichl, Markus; Hess, Michael W.; Fürst, Johannes; Maly, Karl

      2001-01-01

      In alveolar type II cells, the release of surfactant is considerably delayed after the formation of exocytotic fusion pores, suggesting that content dispersal may be limited by fusion pore diameter and subject to regulation at a postfusion level. To address this issue, we used confocal FRAP and N-(3-triethylammoniumpropyl)-4-(4-[dibutylamino]styryl) pyridinium dibromide (FM 1-43), a dye yielding intense localized fluorescence of surfactant when entering the vesicle lumen through the fusion po...

    • Reversible Triplet Energy Transfer between Neo- Alloocimene and Anthracene

      DEFF Research Database (Denmark)

      Gorman, A. A.; Hamblett, I.; Jensen, Niels-Henrik

      1984-01-01

      The rate constants for triplet energy transfer between neo-alloocimene and anthracene have been redetermined by a combination of pulsed laser photolysi......The rate constants for triplet energy transfer between neo-alloocimene and anthracene have been redetermined by a combination of pulsed laser photolysi...

    • Regularities of Twin, Triplet and Multiplet Prime Numbers

      OpenAIRE

      Weber, H. J.

      2011-01-01

      Classifications of twin primes are established and then applied to triplets that generalize to all higher multiplets. Mersenne and Fermat twins and triplets are treated in this framework. Regular prime number multiplets are related to quadratic and cubic prime number generating polynomials.

    • The electronic field shift factor of the 4s2S1/2-4p2PJ transitions in CaII

      International Nuclear Information System (INIS)

      The isotope shifts (IS) of the resonance lines 4s2S1/2-4p2PJ in CaII (seven isotopes) have been measured by fast ion beam collinear laser spectroscopy (FIBCLS) with non-optical detection of the resonant laser-ion interaction. The electronic field shift factor F was derived from the experimental IS via a King plot procedure using the mean square nuclear charge radii from muon spectroscopy and electron scattering. The J-independent result F = -283(6) Mhz/fm2 was obtained. The F-value resulting from extensive many body perturbation theory (MBPT) calculations, recently performed by Maertensson-Pendrill et al., is in excellent agreement with the experimental value, confirming the reliability of the MBPT procedure. (orig.)

    • MiR-152 May Silence Translation of CaMK II and Induce Spontaneous Immune Tolerance in Mouse Liver Transplantation

      Science.gov (United States)

      Wang, Jingcheng; Yan, Sheng; Zhou, Lin; Xie, Haiyang; Chen, Hui; Li, Hui; Zhang, Jinhua; Zhao, Jiacong; Zheng, Shusen

      2014-01-01

      Spontaneous immune tolerance in mouse liver transplantation has always been a hotspot in transplantation-immune research. Recent studies revealed that regulatory T cells (Tregs), hepatic satellite cells and Kupffer cells play a potential role in spontaneous immune tolerance, however the precise mechanism of spontaneous immune tolerance is still undefined. By using Microarray Chips, we investigated different immune regulatory factors to decipher critical mechanisms of spontaneous tolerance after mouse liver transplantation. Allogeneic (C57BL/6-C3H) and syngeneic (C3H-C3H) liver transplantation were performed by 6-8 weeks old male C57BL/6 and C3H mice. Graft samples (N = 4 each group) were collected from 8 weeks post-operation mice. 11 differentially expressed miRNAs in allogeneic grafts (Allografts) vs. syngeneic grafts (Syngrafts) were identified using Agilent Mouse miRNA Chips. It was revealed that 185 genes were modified by the 11 miRNAs, furthermore, within the 185 target genes, 11 of them were tightly correlated with immune regulation after Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis and Genbank data cross-comparison. Verified by real-time PCR and western blot, our results indicated that mRNA expression levels of IL-6 and TAB2 were respectively down regulated following miR-142-3p and miR-155 augment. In addition, increased miR-152 just silenced mRNA of CaMK II and down-regulated translation of CaMK II in tolerated liver grafts, which may play a critical role in immune regulation and spontaneous tolerance induction of mouse liver transplantation. PMID:25133393

    • MiR-152 may silence translation of CaMK II and induce spontaneous immune tolerance in mouse liver transplantation.

      Directory of Open Access Journals (Sweden)

      Yan Wang

      Full Text Available Spontaneous immune tolerance in mouse liver transplantation has always been a hotspot in transplantation-immune research. Recent studies revealed that regulatory T cells (Tregs, hepatic satellite cells and Kupffer cells play a potential role in spontaneous immune tolerance, however the precise mechanism of spontaneous immune tolerance is still undefined. By using Microarray Chips, we investigated different immune regulatory factors to decipher critical mechanisms of spontaneous tolerance after mouse liver transplantation. Allogeneic (C57BL/6-C3H and syngeneic (C3H-C3H liver transplantation were performed by 6-8 weeks old male C57BL/6 and C3H mice. Graft samples (N = 4 each group were collected from 8 weeks post-operation mice. 11 differentially expressed miRNAs in allogeneic grafts (Allografts vs. syngeneic grafts (Syngrafts were identified using Agilent Mouse miRNA Chips. It was revealed that 185 genes were modified by the 11 miRNAs, furthermore, within the 185 target genes, 11 of them were tightly correlated with immune regulation after Gene Ontology (GO, Kyoto Encyclopedia of Genes and Genomes (KEGG analysis and Genbank data cross-comparison. Verified by real-time PCR and western blot, our results indicated that mRNA expression levels of IL-6 and TAB2 were respectively down regulated following miR-142-3p and miR-155 augment. In addition, increased miR-152 just silenced mRNA of CaMK II and down-regulated translation of CaMK II in tolerated liver grafts, which may play a critical role in immune regulation and spontaneous tolerance induction of mouse liver transplantation.

    • Studying Ca uc(ii) K Line Profile Shapes and Dynamic Processes in the Solar Chromosphere at the Base of a Coronal Hole

      Science.gov (United States)

      Grigoryeva, S. A.; Turova, I. P.; Ozhogina, O. A.

      2016-07-01

      We study Ca uc(ii) K profiles in structural features of the quiet chromosphere and plages using observations of two time series for two regions at the base of a coronal hole. One of the regions that we study has a low-brightness area where the reversal-free profile shape remains the same even over a spatial extent of about 16 arcsec. Such a profile shape is typical of low-temperature areas. The analysis of the spectral composition of oscillations has revealed that all the chromospheric structures feature various combinations of periods: 3, 4, 5, and long. One rarely finds only a single period. In same-type structures, we cannot single out a dominant highest-power period; such may be any of the above periods. Periodic brightenings of the violet peak in the Ca uc(ii) K wing occur in both internetwork and network areas. Moreover, they do not arise from purely 3-min oscillations. The integrated spectral power of oscillations throughout the whole area cut out by the spectrograph slit decreases with height from the temperature minimum region to the lower and middle chromosphere in 4.0 - 5.2 (4-min oscillations), 2.4 - 4.0 (5-min oscillations) and 1.1 - 16.0 mHz frequency bands. The oscillation power in the low-frequency band demonstrates a reverse tendency. The oscillation power in 5.2 - 6.8 mHz (3-min oscillations) decreases from the lower to middle chromosphere. This is the case for both regions at the base of a coronal hole. The integrated spectral power distribution in different chromospheric structures is complicated. Low-frequency oscillations are enhanced more often in peripheral areas of structures. Our observations do not corroborate the belief that 3-min oscillations prevail in internetwork and 5-min oscillations in network areas.

    • Triplet-triplet absorption of 2-(2'-hydroxyphenyl) benzoxazole (HBO) in polar solvents

      Science.gov (United States)

      Yang, Guoqiang; Morlet-Savary, Fabrice; Peng, Zhaokui; Wu, Shikang; Fouassier, Jean-Pierre

      1996-07-01

      The transient TT absorption spectra of 2-(2'-hydroxyphenyl) benzoxazole (HBO) have been measured in liquid polar solvents and in polymethylthacrylate. In non-protonic polar solvents the main TT absorption is from the keto form of the compound ( 3K ∗). With a triplet sensitizer the compound just gives a TT absorption of its enol from ( 3E ∗) after triplet energy transfer from the sensitizer to HBO. The excited state intramolecular proton transfer (ESIPT) from the enol form to keto form occurs just in the singlet state. The protonic solvent can break the intramolecular hydrogen bond of HBO and decrease the ESIPT process. In solid solution both 3E ∗ and 3K ∗ can be formed and the TT absorptions were detected because of the inhibition of the rotational conformation transfer.

    • The evolution of substrate specificity-associated residues and Ca(2+) -binding motifs in EF-hand-containing type II NAD(P)H dehydrogenases.

      Science.gov (United States)

      Hao, Meng-Shu; Rasmusson, Allan G

      2016-07-01

      Most eukaryotic organisms, except some animal clades, have mitochondrial alternative electron transport enzymes that allow respiration to bypass the energy coupling in oxidative phosphorylation. The energy bypass enzymes in plants include the external type II NAD(P)H dehydrogenases (DHs) of the NDB family, which are characterized by an EF-hand domain for Ca(2+) binding. Here we investigate these plant enzymes by combining molecular modeling with evolutionary analysis. Molecular modeling of the Arabidopsis thaliana AtNDB1 with the yeast ScNDI1 as template revealed distinct similarities in the core catalytic parts, and highlighted the interaction between the pyridine nucleotide and residues correlating with NAD(P)H substrate specificity. The EF-hand domain of AtNDB1 has no counterpart in ScNDI1, and was instead modeled with Ca(2+) -binding signal transducer proteins. Combined models displayed a proximity of the AtNDB1 EF-hand domain to the substrate entrance side of the catalytic part. Evolutionary analysis of the eukaryotic NDB-type proteins revealed ancient and recent reversions between the motif observed in proteins specific for NADH (acidic type) and NADPH (non-acidic type), and that the clade of enzymes with acidic motifs in angiosperms derives from non-acidic-motif NDB-type proteins present in basal plants, fungi and protists. The results suggest that Ca(2+) -dependent external NADPH oxidation is an ancient process, indicating that it has a fundamental importance for eukaryotic cellular redox metabolism. In contrast, the external NADH DHs in plants are products of a recent expansion, mirroring the expansion of the alternative oxidase family. PMID:27079180

    • Three-dimensional localization of the α and β subunits and of the II-III loop in the skeletal muscle L-type Ca2+ channel.

      Science.gov (United States)

      Szpyt, John; Lorenzon, Nancy; Perez, Claudio F; Norris, Ethan; Allen, Paul D; Beam, Kurt G; Samsó, Montserrat

      2012-12-21

      The L-type Ca(2+) channel (dihydropyridine receptor (DHPR) in skeletal muscle acts as the voltage sensor for excitation-contraction coupling. To better resolve the spatial organization of the DHPR subunits (α(1s) or Ca(V)1.1, α(2), β(1a), δ1, and γ), we created transgenic mice expressing a recombinant β(1a) subunit with YFP and a biotin acceptor domain attached to its N- and C- termini, respectively. DHPR complexes were purified from skeletal muscle, negatively stained, imaged by electron microscopy, and subjected to single-particle image analysis. The resulting 19.1-Å resolution, three-dimensional reconstruction shows a main body of 17 × 11 × 8 nm with five corners along its perimeter. Two protrusions emerge from either face of the main body: the larger one attributed to the α(2)-δ1 subunit that forms a flexible hook-shaped feature and a smaller protrusion on the opposite side that corresponds to the II-III loop of Ca(V)1.1 as revealed by antibody labeling. Novel features discernible in the electron density accommodate the atomic coordinates of a voltage-gated sodium channel and of the β subunit in a single docking possibility that defines the α1-β interaction. The β subunit appears more closely associated to the membrane than expected, which may better account for both its role in localizing the α(1s) subunit to the membrane and its suggested role in excitation-contraction coupling. PMID:23118233

    • Nonextensive triplet in a geological faults system

      Science.gov (United States)

      de Freitas, D. B.; França, G. S.; Scherrer, T. M.; Vilar, C. S.; Silva, R.

      2013-05-01

      The San Andreas fault (SAF) in the USA is one of the most investigated self-organizing systems in Nature. In this paper, we studied some geophysical properties of the SAF system in order to analyze the behavior of earthquakes in the context of Tsallis's q-Triplet. To this end, we considered 134573 earthquake events in the magnitude interval 2\\leq m<8 , taken from the Southern Earthquake Data Center (SCEDC, 1932-2012). The values obtained (“q-Triplet”{}\\equiv\\{q_{\\textit{stat}},q_{\\textit{sen}},q_{\\textit{rel}}\\} ) reveal that the q_{\\textit{stat}} -Gaussian behavior of the aforementioned data exhibit long-range temporal correlations. Moreover, q_{\\textit{sen}} exhibits quasi-monofractal behavior with a Hurst exponent of 0.87.

    • Bright Solid State Source of Photon Triplets

      CERN Document Server

      Khoshnegar, Milad; Predojević, Ana; Dalacu, Dan; Prilmüller, Maximilian; Lapointe, Jean; Wu, Xiaohua; Tamarat, Philippe; Lounis, Brahim; Poole, Philip; Weihs, Gregor; Majedi, Hamed

      2015-01-01

      Producing advanced quantum states of light is a priority in quantum information technologies. While remarkable progress has been made on single photons and photon pairs, multipartite correlated photon states are usually produced in purely optical systems by post-selection or cascading, with extremely low efficiency and exponentially poor scaling. Multipartite states enable improved tests of the foundations of quantum mechanics as well as implementations of complex quantum optical networks and protocols. It would be favorable to directly generate these states using solid state systems, for better scaling, simpler handling, and the promise of reversible transfer of quantum information between stationary and flying qubits. Here we use the ground states of two optically active coupled quantum dots to directly produce photon triplets. The wavefunctions of photogenerated excitons localized in these ground states are correlated via molecular hybridization and Coulomb interactions. The formation of a triexciton leads...

    • Triplet to Singleton-A Successful Outcome

      Directory of Open Access Journals (Sweden)

      Priya Varshney

      2014-07-01

      Full Text Available We are presenting a case report of triplet pregnancy in a 25 years old lady, in whom single fetal reduction was done at 10 weeks. At 29 weeks, ultrasonography showed fetal demise of second twin. Conservative management was done, after evaluating the status of second twin. Maternal and fetal monitoring was done with PT INR, Ultrasound Doppler weekly till 33 weeks when an emergency cesarean was done due to preterm labour pains. A healthy baby of 1.8 kg was born along with a macerated IUD of 500 gms. Mother and baby are healthy on follow up till date. Hence conservative management should be followed in single fetus demise in twin pregnancy with proper monitoring.

    • Magnetic chains on a triplet superconductor.

      Science.gov (United States)

      Sacramento, P D

      2015-11-11

      The topological state of a two-dimensional triplet superconductor may be changed by an appropriate addition of magnetic impurities. A ferromagnetic magnetic chain at the surface of a superconductor with spin-orbit coupling may eliminate the edge states of a finite system giving rise to localized zero modes at the edges of the chain. The coexistence/competition between the two types of zero modes is considered. The reduction of the system to an effective 1d system gives partial information on the topological properties but the study of the two sets of zero modes requires a two-dimensional treatment. Increasing the impurity density from a magnetic chain to magnetic islands leads to a finite Chern number. At half-filling small concentrations are enough to induce chiral modes. PMID:26459719

    • TRIPLET CIRCULAR HOUGH TRANSFORM FOR CIRCLE DETECTION

      Institute of Scientific and Technical Information of China (English)

      Luo Daisheng; He Xiaohai; Teng Qizhi; Tao Qingchuan

      2002-01-01

      A new method, triplet circular Hough transform, is proposed for circle detection in image processing and pattern recognition. In the method, a curve in an image is first detected.Next, a sequence of three points on the curve are selected, a sequence of parameters (a,b,r)corresponding to the three points are calculated by solving the circle equation of the curve, and two 2-D accumulators A(a,b) and R(a,b) are accumulated with 1 and r, respectively. Then the parameters {(a, b, r)} of the circles fitting the curve are determined from A(a, b) and R(a, b) by searching for the local maximum over A(a,b). Because no computation loops over center (a, b)and/or radius r are needed, the method is faster than the basic and directional gradient methods.It needs also much smaller memory for accumulation.

  1. CA2+/CALMODULIN-DEPENDENT KINASE II- ASSOCIATES WITH THE C TERMINUS OF THE DOPAMINE TRANSPORTER AND INCREASES AMPHETAMINE-INDUCED DOPAMINE EFFLUX VIA PHOSPHORYLATION OF N-TERMINAL SERINES

    DEFF Research Database (Denmark)

    Fog, Jacob; Khoshbouei, H; Holy, M;

    The dopamine transporter(DAT) plays a key role in clearing extracellular dopamine(DA) from the synapse. Moreover DAT is a target for the action of widely abused psychostimulants such as cocaine and amphetamine(AMPH). AMPH is a substrate for the DAT and promotes the reversal of transport and thus...... dependent kinase II- (CaMKII- ). A direct interaction between CaMKII- and DAT C-terminus was verified by the ability of C-terminal DAT GST fusion proteins to pull down both purified CaMKII- and CaMKII- from rat brain extracts. The ability of CaMKII- to exist in a complex with DAT was supported by co...

  2. Characterization of calcareous deposits in artificial seawater by impedance techniques 3--Deposit of CaCO{sub 3} in the presence of Mg(II)

    Energy Technology Data Exchange (ETDEWEB)

    Barchiche, Ch.; Deslouis, C.; Festy, D.; Gil, O.; Refait, Ph.; Touzain, S.; Tribollet, B

    2003-05-30

    Calcareous deposits were formed on steel under cathodic protection conditions in artificial seawater at various potentials from -0.9 to -1.4 V/SCE. The deposition kinetics was analysed by chronoamperometry measurements and the calcareous layers were characterized by electrochemical and electrohydrodynamical impedance spectroscopies, scanning electron microscopy observations and X-ray diffraction analyses. At 20 deg. C, the deposits were composed of aragonite CaCO{sub 3} when formed at potentials E comprised between -0.9 and -1.1 V/SCE, of brucite Mg(OH){sub 2} and aragonite when formed at -1.2 V/SCE, and only of brucite when formed at potentials E{<=}-1.3 V/SCE. However, the in situ impedance techniques demonstrated the presence of a Mg(II)-containing porous layer along with the aragonite deposit at E{>=}-1.1 V/SCE. In seawater enriched with Mg{sup 2+}, the deposition of aragonite was almost totally inhibited, and the behavior of the film containing Mg(II) could be described.

  3. Characterization of calcareous deposits in artificial seawater by impedance techniques 3--Deposit of CaCO3 in the presence of Mg(II)

    International Nuclear Information System (INIS)

    Calcareous deposits were formed on steel under cathodic protection conditions in artificial seawater at various potentials from -0.9 to -1.4 V/SCE. The deposition kinetics was analysed by chronoamperometry measurements and the calcareous layers were characterized by electrochemical and electrohydrodynamical impedance spectroscopies, scanning electron microscopy observations and X-ray diffraction analyses. At 20 deg. C, the deposits were composed of aragonite CaCO3 when formed at potentials E comprised between -0.9 and -1.1 V/SCE, of brucite Mg(OH)2 and aragonite when formed at -1.2 V/SCE, and only of brucite when formed at potentials E≤-1.3 V/SCE. However, the in situ impedance techniques demonstrated the presence of a Mg(II)-containing porous layer along with the aragonite deposit at E≥-1.1 V/SCE. In seawater enriched with Mg2+, the deposition of aragonite was almost totally inhibited, and the behavior of the film containing Mg(II) could be described

  4. X-ray instrumentation in astronomy II; Proceedings of the Meeting, San Diego, CA, Aug. 15-17, 1988

    International Nuclear Information System (INIS)

    Various papers on X-ray instrumentation in astronomy are presented. Individual topics addressed include: concentrating hard X-ray collector, advanced X-ray Astrophysics Facility high resolution camera, Fano-noise-limited CCDs, linear CCD with enhanced X-ray quantum efficiency, advances in microchannel plate detectors, X-ray imaging spectroscopy with EEV CCDs, large aperture imaging gas scintillation proportional counter, all-sky monitor for the X-ray Timing Explorer, and miniature satellite technology capabilities for space astronomy. Also discussed are: high-resolution X-ray spectroscopy using microcalorimeters, high-throughput X-ray astrophysics cornerstone, gas mixtures for X-ray proportional counters, transmission grating spectrometer for SPEKTROSAT, efficiency of X-ray reflection gratings, soft X-ray spectrographs for solar observations, observability of coronal variations, Berkeley extreme-UV calibration facility, SURF-II radiometric instrumentation calibration facility, and evaluation of toroidal gratings in the EUV

  5. Non-Linear Advanced Control of the LHC Inner Triplet Heat Exchanger Test Unit

    CERN Document Server

    Blanco-Viñuela, E; De Prada-Moraga, C; Cristea, S

    2002-01-01

    The future Large Hadron Collider (LHC) at CERN will include eight interaction region final focus magnet systems, the so-called "Inner Triplet", one on each side of the four beam collision points. The Inner Triplets will be cooled in a static bath of pressurized He II nominally at 1.9 K. This temperature is a control parameter and has very severe constraints in order to avoid the transition from the superconducting to normal resistive state. The main difference in these special zones with respect to a regular LHC cell is higher dynamic heat load unevenly distributed which modifies largely the process characteristics and hence the controller performance. Several control strategies have already been tested at CERN in a pilot plant (LHC String Test) which reproduced a LHC half-cell. In order to validate a common control structure along the whole LHC ring, a Nonlinear Model Predictive Control (NMPC) has been developed and implemented in the Inner Triplet Heat Exchanger Unit (IT-HXTU) at CERN. Automation of the Inn...

  6. Crystal structures of hydrates of simple inorganic salts. II. Water-rich calcium bromide and iodide hydrates: CaBr2 · 9H2O, CaI2 · 8H2O, CaI2 · 7H2O and CaI2 · 6.5H2O.

    Science.gov (United States)

    Hennings, Erik; Schmidt, Horst; Voigt, Wolfgang

    2014-09-01

    Single crystals of calcium bromide enneahydrate, CaBr(2) · 9H2O, calcium iodide octahydrate, CaI(2) · 8H2O, calcium iodide heptahydrate, CaI(2) · 7H2O, and calcium iodide 6.5-hydrate, CaI(2) · 6.5H2O, were grown from their aqueous solutions at and below room temperature according to the solid-liquid phase diagram. The crystal structure of CaI(2) · 6.5H2O was redetermined. All four structures are built up from distorted Ca(H2O)8 antiprisms. The antiprisms of the iodide hydrate structures are connected either via trigonal-plane-sharing or edge-sharing, forming dimeric units. The antiprisms in calcium bromide enneahydrate are monomeric. PMID:25186361

  7. Ground state of naphthyl cation: Singlet or triplet?

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, Achintya Kumar; Vaval, Nayana, E-mail: np.vaval@ncl.res.in; Pal, Sourav, E-mail: s.pal@ncl.res.in [Physical Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008 (India); Manohar, Prashant U. [Department of Chemistry, BITS Pilani, Pilani Campus (India)

    2014-03-21

    We present a benchmark theoretical investigation on the electronic structure and singlet-triplet(S-T) gap of 1- and 2-naphthyl cations using the CCSD(T) method. Our calculations reveal that the ground states of both the naphthyl cations are singlet, contrary to the results obtained by DFT/B3LYP calculations reported in previous theoretical studies. However, the triplet states obtained in the two structural isomers of naphthyl cation are completely different. The triplet state in 1-naphthyl cation is (π,σ) type, whereas in 2-naphthyl cation it is (σ,σ{sup ′}) type. The S-T gaps in naphthyl cations and the relative stability ordering of the singlet and the triplet states are highly sensitive to the basis-set quality as well as level of correlation, and demand for inclusion of perturbative triples in the coupled-cluster ansatz.

  8. Left-right symmetric model with SU(2)-triplet fermions

    International Nuclear Information System (INIS)

    We consider an SU(3)c x SU(2)L x SU(2)R x U(1)B-L left-right symmetric model with three Higgs scalars including an SU(2)L doublet, an SU(2)R doublet and an SU(2)L x SU(2)R bidoublet. In addition to usual SU(2)-doublet fermions, our model contains SU(2)-triplet fermions with Majorana masses. The neutral components of the left-handed triplets can contribute a canonical seesaw while the neutral components of the right-handed triplets associated with the right-handed neutrinos can contribute a double/inverse-type seesaw. Our model can be embedded into an SO(10) grand unification theory where the triplets belong to the 45=(1,3,1,0)+(1,1,3,0)+... representations.

  9. Development of Q-triplets for interdigital-H linac

    International Nuclear Information System (INIS)

    In the prototype facility of the Exotic-arena at INS, unstable nuclei with a charge-to-mass ratio greater than 1/10 is accelerated from 170 to 1046 keV/u by an interdigital-H linac. IH linac consists of four tanks and three Q-triplets placed between tanks. In this type, the length of Q-triplets should be as short as possible in order to obtain a large longitudinal acceptance. The Q-triplet with high gradient and compact size was designed by 2D and 3D computer codes. A prototype model of the Q-triplet was constructed. The field measurement with a hole probe, carried out. (author)

  10. Stability constraints in triplet extension of MSSM

    CERN Document Server

    Das, Moumita; Roy, Sourov

    2015-01-01

    We study the stability constraints on the parameter space of a triplet extension of MSSM. Existence of unbounded from below directions in the potential can spoil successful Electroweak (EW) symmetry breaking by making the corresponding minimum unstable, and hence the model should be free from those directions. Avoiding those directions restricts the parameter space of the model. We derive four stability constraints, of which only three independent from each other. After scanning the model's parameter space for phenomenologically viable data points, we impose the stability constraints and find that only about a quarter of the data points features a stable EW minimum. At those data points featuring stability, $\\mu$ and the up Higgs soft mass turn out to be smaller than about a TeV in absolute value, which make the mass of the lightest chargino and neutralino smaller than about 700 GeV. Two relevant phenomenological consequences of lifting the unbounded from below directions are that the lightest Higgs boson dec...

  11. Pair Triplet Association Rule Generation in Streams

    Directory of Open Access Journals (Sweden)

    Manisha Thool

    2013-08-01

    Full Text Available Many applications involve the generation and analysis of a new kind of data, called stream data, where data flows in and out of an observation platform or window dynamically. Such data streams have the unique features such as huge or possibly infinite volume, dynamically changing, flowing in or out in a fixed order, allowing only one or a small number of scans. An important problem in data stream mining is that of finding frequent items in the stream. This problem finds application across several domains such as financial systems, web traffic monitoring, internet advertising, retail and e-business. This raises new issues that need to be considered when developing association rule mining technique for stream data. The Space-Saving algorithm reports both frequent and top-k elements with tight guarantees on errors. We also develop the notion of association rules in streams of elements. The Streaming-Rules algorithm is integrated with Space-Saving algorithm to report 1-1 association rules with tight guarantees on errors, using minimal space, and limited processing per element and we are using Apriori algorithm for static datasets and generation of association rules and implement Streaming-Rules algorithm for pair, triplet association rules. We compare the top- rules of static datasets with output of stream datasets and find percentage of error.

  12. Deconstructing triplet nucleon-nucleon scattering

    International Nuclear Information System (INIS)

    Nucleon-nucleon scattering in spin-triplet channels is analyzed within an effective field theory where one-pion exchange is treated nonperturbatively. Justifying this requires the identification of an additional low-energy scale in the strength of that potential. Short-range interactions are organized according to the resulting power counting, in which the leading term is promoted to significantly lower order than in the usual perturbative counting. In each channel there is a critical momentum above which the waves probe the singular core of the tensor potential and the new counting is necessary. When the effects of one- and two-pion exchange have been removed using a distorted-wave Born approximation, the residual scattering in waves with L≤2 is well described by the first three terms in the new counting. In contrast, the scattering in waves with L≥3 is consistent with the perturbative counting, at least for energies up to 300 MeV. This pattern is in agreement with estimates of the critical momenta in these channels

  13. Triplet Higgs Collider Phenomenology after LHC

    CERN Document Server

    Englert, Christoph; Spannowsky, Michael

    2013-01-01

    ATLAS and CMS have discovered a Standard Model Higgs-like particle. One of the main discovery channels is the Higgs decay to two photons, which, at the moment, seems to be considerably enhanced over the Standard Model expectation. Models with additional charged matter coupling to the Higgs sector can enhance or decrease the Higgs to two photons branching ratio. We take this as motivation to confront the so-called Georgi-Machacek model of Higgs triplets with the results of recent searches for a SM Higgs boson performed at the LHC. We also investigate the model in regions of the allowed parameter space relevant for a SM-like phenomenology. The Georgi-Machacek model avoids tree-level issues of the T parameter, while offering a vastly modified Higgs phenomenology compared to the Standard Model. This comes at the price of introducing another fine-tuning problem related to electroweak precision measurements. We investigate the collider phenomenology of the Georgi-Machacek model in the light of existing collider con...

  14. Triplet Pairing in pure neutron matter

    CERN Document Server

    Srinivas, Sarath

    2016-01-01

    We study the zero temperature BCS gaps for the triplet channel in pure neutron matter using Similarity Renormalization Group (SRG) evolved interactions. We use the dependence of the results on the SRG resolution scale, as a tool to analyze medium and many-body corrections. In particular, we study the effects of including the three-body interactions at leading order, which appear at N2LO in the Chiral EFT, as well as that of the first-order self-energy corrections on the zero temperature gap. In addition we also extract the transition temperature as a function of densities and verify the BCS scaling of the zero temperature gaps to the transition temperature. We observe that the self-energy effects are very crucial in order to reduce the SRG resolution scale dependence of the results, while the three-body effects at the leading order do not change the two-body resolution scale dependence. On the other hand, the results depend strongly on the three-body cut-off, emphasizing the importance of the missing higher-o...

  15. TRIPLET CIRCULAR HOUGH TRANSFORM FOR CIRCLE DETECTION

    Institute of Scientific and Technical Information of China (English)

    LuoDaisheng; HeXiaohai; 等

    2002-01-01

    A new method,triplet circular Hough transform,is proposed for circle detection in image processing and pattern recognition.In the method,a curve in an image is first detected.Next,a sequence of three points on the curve are selected.a sequence of parameters(a,b,r)corresponding to the three points are calculated by solving the circle equation of the curve,and two 2-D accumulators A(a,b)and R(a,b)are accumulated with 1 and r,respectively,Then the parameters{(a,b,r)}of the circles fitting the curve are determined from A(a,b)and R(a,b) by searching for the local maximum over A(a,b).Because no computation loops over center(a,b) and/or radius r are needed,the method is faster than the basic and directional gradient methods It needs also much smaller memory for accumulation.

  16. New insights into DNA triplexes: residual twist and radial difference as measures of base triplet non-isomorphism and their implication to sequence-dependent non-uniform DNA triplex

    OpenAIRE

    Thenmalarchelvi, R.; Yathindra, N

    2005-01-01

    DNA triplexes are formed by both isomorphic (structurally alike) and non-isomorphic (structurally dissimilar) base triplets. It is espoused here that (i) the base triplet non-isomorphism may be articulated in structural terms by a residual twist (Δt°), the angle formed by line joining the C1′…C1′ atoms of the adjacent Hoogsteen or reverse Hoogsteen (RH) base pairs and the difference in base triplet radius (Δr Å), and (ii) their influence on DNA triplex is largely mechanistic, leading to the p...

  17. Aluminum resistance in wheat involves maintenance of leaf Ca(2+) and Mg(2+) content, decreased lipid peroxidation and Al accumulation, and low photosystem II excitation pressure.

    Science.gov (United States)

    Moustaka, Julietta; Ouzounidou, Georgia; Bayçu, Gülriz; Moustakas, Michael

    2016-08-01

    The phytotoxic aluminum species (Al(3+)) is considered as the primary factor limiting crop productivity in over 40 % of world's arable land that is acidic. We evaluated the responses of two wheat cultivars (Triticum aestivum L.) with differential Al resistance, cv. Yecora E (Al-resistant) and cv. Dio (Al-sensitive), exposed to 0, 37, 74 and 148 μM Al for 14 days in hydroponic culture at pH 4.5. With increasing Al concentration, leaf Ca(2+) and Mg(2+) content decreased, as well as the effective quantum yield of photosystem II (PSII) photochemistry (Φ PSII ), while a gradual increase in leaf membrane lipid peroxidation, Al accumulation, photoinhibition (estimated as F v /F m ), and PSII excitation pressure (1 - q p ) occurred. However, the Al-resistant cultivar with lower Al accumulation, retained larger concentrations of Ca(2+) and Mg(2+) in the leaves and kept a larger fraction of the PSII reaction centres (RCs) in an open configuration, i.e. a higher ratio of oxidized to reduced quinone A (QA), than plants of the Al-sensitive cultivar. Four times higher Al concentration in the nutrient solution was required for Al-resistant plants (148 μM Al) than for Al-sensitive (37 μM Al), in order to establish the same closed RCs. Yet, the decline in photosynthetic efficiency in the cultivar Dio was not only due to closure of PSII RCs but also to a decrease in the quantum yield of the open RCs. We suggest that Al(3+) toxicity may be mediated by nutrient deficiency and oxidative stress, and that Al-resistance of the wheat cultivar Yecora E, may be due at least partially, from the decreased Al accumulation that resulted to decreased reactive oxygen species (ROS) formation. However, under equal internal Al accumulation (exposure Al concentration: Dio 74 μM, Yecora E 148 μM) that resulted to the same oxidative stress, the reduced PSII excitation pressure and the better PSII functioning of the Al-resistant cultivar was probably due to the larger concentrations of Ca

  18. Coexistence of ferromagnetism and superconductivity in semimetals (Triplet pairing case)

    International Nuclear Information System (INIS)

    The possibility of coexistence of ferromagnetic ordering and superconductivity in a two-band model of a semimetal with an isotopic current carrier spectrum is investigated in detail. It is shown that for unequal electron and hole concentrations triplet electron-hole and triplet cooper pairings with weak electron coupling may coexist. In this case a nonvanishing mean magnetic moment appears. (author). 9 refs., 4 figs

  19. Triplet repeat length bias and variation in the human transcriptome

    OpenAIRE

    Molla, Michael; Delcher, Arthur; Sunyaev, Shamil; Cantor, Charles; Kasif, Simon

    2009-01-01

    Length variation in short tandem repeats (STRs) is an important family of DNA polymorphisms with numerous applications in genetics, medicine, forensics, and evolutionary analysis. Several major diseases have been associated with length variation of trinucleotide (triplet) repeats including Huntington's disease, hereditary ataxias and spinobulbar muscular atrophy. Using the reference human genome, we have catalogued all triplet repeats in genic regions. This data revealed a bias in noncoding D...

  20. Higher-Spin Triplet Fields and String Theory

    Directory of Open Access Journals (Sweden)

    D. Sorokin

    2010-01-01

    Full Text Available We review basic properties of reducible higher-spin multiplets, called triplets, and demonstrate how they naturally appear as part of the spectrum of String Field Theory in the tensionless limit. We show how in the frame-like formulation the triplet fields are endowed with the geometrical meaning of being components of higher-spin vielbeins and connections and present actions describing their free dynamics.

  1. Formylmethylene: the triplet ground state and the lowest singlet state

    OpenAIRE

    Guan, Jun; Randall, Katherine R.; Li, Huidong; Schaefer, Henry F. III

    2013-01-01

    The ground triplet state and lowest singlet state of formylmethylene have been proposed as important intermediates in the Wolff rearrangement of α-diazo ketones into ketenes. The ground triplet state of formylmethylene has been examined experimentally, but the lowest singlet state has yet to be observed. We predict equilibrium geometries, energies, bonding, dipole moments, and harmonic vibrational frequencies for these two lowest states of formylmethylene at the cc-pVQZ CCSD...

  2. The Scalar Triplet Contribution to Lepton Flavour Violation and Neutrinoless Double Beta Decay in Left-Right Symmetric Model

    CERN Document Server

    Bambhaniya, Gulab; Goswami, Srubabati; Mitra, Manimala

    2015-01-01

    We analyse in detail the scalar triplet contribution to the low-energy lepton flavour violating (LFV) and lepton number violating (LNV) processes within a TeV-scale left-right symmetric framework. We show that in both type-I and type-II seesaw dominance for the light neutrino masses, the triplet of comparable or smaller mass than the largest right-handed neutrino mass scale can give sizeable contribution to the LFV processes, except in the quasi-degenerate limit of light neutrino masses, where a suppression can occur due to cancellations. In particular, a moderate value of the heaviest neutrino to scalar triplet mass ratio $r\\lesssim {\\cal O}(1)$ is still experimentally allowed and can be explored in the future LFV experiments. Similarly, the contribution of a relatively light triplet to the LNV process of neutrinoless double beta decay could be significant, disfavouring a part of the model parameter space otherwise allowed by LFV constraints. Nevertheless, we find regions of parameter space consistent with b...

  3. Binary biosorption of uranium(VI) and nickel(II) from aqueous solution by Ca-pretreated Cystoseira indica in a fixed-bed column

    International Nuclear Information System (INIS)

    Simultaneous biosorption of uranium(VI) and nickel(II) ions onto Ca-pretreated Cystoseira indica biomass was studied and compared with single uranium or nickel biosorption in a fixed-bed column. Results of single biosorption showed the breakthrough and exhaustion time increase with the increase of the flow rate and inlet metal concentration for both metal ions. Also, it was observed that there was an optimum flow rate of 1.4 mL min-1 (surface loading of 0.792 cm min-1) for both metal ions in the column. Results from both single and binary systems showed the adsorption capacity of C. indica for both metal ions increases with the increasing inlet concentration of each component and C. indica had a stronger affinity for uranium than nickel ions. The binary system results showed that the presence of the second component affected the adsorption of the first one by C. indica so the antagonistic action was observed. Also, the inhibitory effect of uranium ions on the nickel adsorption was greater than nickel ions on the uranium adsorption. The uranium and nickel breakthrough curves under different conditions were described by the Thomas, Yoon-Nelson and Yan models. Among these models, the Yan model appeared to describe the experimental results better. (author)

  4. Line absorption of He-like triplet lines by Li-like ions. Caveats of using line ratios of triplets for plasma diagnostics

    OpenAIRE

    Mehdipour, M.; Kaastra, J. S.; Raassen, A. J. J.

    2015-01-01

    He-like ions produce distinctive series of triplet lines under various astrophysical conditions. However, this emission can be affected by line absorption from Li-like ions in the same medium. We investigate this absorption of He-like triplets and present the implications for diagnostics of plasmas in photoionisation equilibrium using the line ratios of the triplets. Our computations were carried out for the O VI and Fe XXIV absorption of the O VII and Fe XXV triplet emission lines, respectiv...

  5. [Neonatal morbidity and hospital mortality of preterm triplets.

    Science.gov (United States)

    Lamshing-Salinas, Priscilla; Rend Ón-Macías, Mario Enrique; Iglesias-Leboreiro, José; Bernárdez-Zapata, Isabel; Braverman-Bronstein, Ariela

    2013-01-01

    Background: multiple gestations have caused an increase in vulnerable preterm births. Our objective was to analyze neonatal morbidity and mortality in preterm triplets. Methods: we analyzed a cohort of 30 triplets in an obstetrics and gynecology hospital. Data were obtained during pregnancy, childbirth and neonatal period: birth order, sex, weight, height, malformations, advanced resuscitation, assisted ventilation, intraventricular hemorrhage, necrotizing enterocolitis, sepsis, pulmonary hypertension, bronchopulmonary dysplasia, days of hospitalization, and death. Results: 90 infants were analyzed. There was an omphalopagus con-joined twins case; 42 (70 %) had between 30-33 weeks and six between 24-29; 19 (21 %) had low weight for gestational age, and 18 (30 %) had a major malformation; 27 % required ventilatory support, 33 % sepsis, 32 % necrotizing enterocolitis, 21 % pulmonary hypertension, 14 % bronchopulmonary dysplasia and 2 % intraventricular hemorrhage, without statistically significant differences related to the order, presentation at birth, sex and number of placentas and amniotic sacs. Eight 24-week triplets died, four over 28 weeks, and a siamese (p = 38). There was no difference in hospital days between triplets. Conclusions: the triplets mortality is low and mainly associated with extreme prematurity, intrauterine growth restriction and sepsis. PMID:24290011

  6. Rates and singlet/triplet ratios from TADF transients

    CERN Document Server

    Nelson, Mitchell C

    2016-01-01

    Thermally activated delayed fluorescence has been reported in a number of OLED emitter materials engineered to have low singlet-triplet energy gaps. Here we derive closed solutions for steady state and transient behaviors and apply these results to data provided in recent reports. Earlier work has used yields, rates and a supplied forward crossing rate to estimate the reverse crossing rate and then obtain the singlet-triplet energy gap in a log-linear fit. In this work we use only the system relaxation times and obtain all five of the system constants: the singlet and triplet relaxation rates, the forward and reverse crossing rates and the singlet-triplet energy gap. These are then used to calculate the fluorescent/phosphorescent ratio and the singlet/triplet population ratio. Good fits are obtained for data from 4CzIPN and from the excimer m-MTDATA:t-Bu-PBD and the results appear to be consistent with the reported behaviors of OLEDS using these materials.

  7. Long-Lived, Colour-Triplet Scalars from Unnaturalness

    CERN Document Server

    Barnard, James; Gherghetta, Tony; Spray, Andrew

    2015-01-01

    Long-lived, colour-triplet scalars are a generic prediction of unnatural, or split, composite Higgs models where the spontaneous global-symmetry breaking scale $f \\gtrsim 10$ TeV and an unbroken $SU(5)$ symmetry is preserved. Since the triplet scalars are pseudo Nambu-Goldstone bosons they are split from the much heavier composite-sector resonances and are the lightest exotic, coloured states. This makes them ideal to search for at colliders. Due to discrete symmetries the triplet scalar decays via a dimension-six term and given the large suppression scale $f$ is often metastable. We show that existing searches for collider-stable R-hadrons from Run-I at the LHC forbid a triplet scalar mass below 845 GeV, whereas with $300\\,\\mathrm{fb}^{-1}$ at 13 TeV triplet scalar masses up to 1.4 TeV can be discovered. For shorter lifetimes displaced-vertex searches provide a discovery reach of up to 1.8 TeV. In addition we present exclusion and discovery reaches of future hadron colliders as well as indirect limits that a...

  8. Photosensitized reactions initiated by 6-carboxypterin: singlet and triplet reactivity.

    Science.gov (United States)

    Tinel, L; Rossignol, S; Ciuraru, R; Dumas, S; George, C

    2016-06-22

    Pterins, derivatives of 2-aminopteridin-4(3H)-one, are natural photosensitizers, common to many biological systems. Indications that these photosensitizers are also present in the sea-surface microlayer motivated the study of the photophysical and photochemical properties of 6-carboxypterin (CPT), which was chosen as a model for this group of photoactive compounds. The kinetics of excited CPT in the singlet and triplet state in the presence of halides and organics were studied in aqueous solutions at neutral pH by means of steady-state fluorescence and laser-flash photolysis. The fluorescence of CPT was efficiently quenched by two halides (iodide and bromide) and by four carboxylic acids (lactic, malonic, propionic and citric acid) with reaction rates close to the diffusion-controlled limit. In the triplet state, the triplet absorption spectrum was measured and its pH dependence was studied. The triplet state of CPT showed relatively high reactivity towards iodide, but no reaction with bromide or chloride could be observed. No singlet or triplet state quenching in the presence of limonene could be measured. A reaction mechanism is proposed, initiated by electron transfer from the quencher to the excited photosensitizer. This type of photo-induced reaction in the sea-surface microlayer has the potential to trigger the production of many oxidized species, including halogen atoms, in the bulk and gaseous phases. PMID:27296228

  9. Manipulating rogue wave triplet in optical waveguides through tapering

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Rama [Department of Physics, DAV University, Jalandhar 144008 (India); Kumar, C.N., E-mail: cnkumar@pu.ac.in [Department of Physics, Panjab University, Chandigarh 160014 (India); Vyas, Vivek M. [Institute of Mathematical Sciences, CIT Campus, Taramani, Chennai 600 113 (India); Panigrahi, Prasanta K., E-mail: pprasanta@iiserkol.ac.in [Indian Institute of Science Education and Research – Kolkata, Mohanpur, Nadia 741252 (India)

    2015-02-06

    Taking account of the results of the paper, published in [21] (Chabchoub and Akhmediev, 2013), containing experimental generation of rogue wave triplets in the water tank, we demonstrate a theoretical approach to coherently control the rogue wave triplet dynamics and spectral spread in a tapered index optical waveguide. The relative distance between the successive waves of the triplet, along both longitudinal and transverse axes, can be manipulated by modulating the tapering of the waveguide. This not only significantly enhances the possibility of observing these statistically rare events in the waveguide, but can also controllably amplify the intensity and spectral spread, the desired features for supercontinuum generation. The controlling of real Riccati parameter intrinsically arises from the allowed phase variation of the self-similar solutions of the nonlinear Schrödinger equation. - Highlights: • Manipulating rogue wave triplets in GNLSE using Riccati parameter is outlined. • Symmetric transformations used to scale mutual spacing in a triplet. • Results presented for sech{sup 2}-type tapered waveguides.

  10. Magnetism of CaAs, CaP, and CaN half-metals

    International Nuclear Information System (INIS)

    First principles calculations indicate that CaAs, CaP, and CaN compounds are ferromagnets. Analysis of these and other II-V compounds that do not contain transition metal atoms shows that their magnetism derives from the spin polarization of the atomic p(anion) orbitals, which persists in the compounds of Ca, Sr, and Ba due to their large atomic radii

  11. Magnetism of CaAs, CaP, and CaN half-metals

    Energy Technology Data Exchange (ETDEWEB)

    Volnianska, O. [Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw (Poland)]. E-mail: volnian@ifpan.edu.pl; Jakubas, P. [Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw (Poland); Boguslawski, P. [Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw (Poland)

    2006-10-26

    First principles calculations indicate that CaAs, CaP, and CaN compounds are ferromagnets. Analysis of these and other II-V compounds that do not contain transition metal atoms shows that their magnetism derives from the spin polarization of the atomic p(anion) orbitals, which persists in the compounds of Ca, Sr, and Ba due to their large atomic radii.

  12. El sitio Bajo del Coypar II: Las evidencias más tempranas (CA. 1000 AP) del proceso agropastoril en la Puna Meridional Argentina (Antofagasta de la Sierra, Catamarca)

    OpenAIRE

    Silvina Vigliani

    2005-01-01

    El sitio Bajo del Coypar II (BC II) es un conjunto de estructuras de pequeñas dimensiones ubicado sobre una saliente de la ladera de los cerros del Coypar, frente y alrededor del cual se distribuye una gran superficie de campos de cultivo prehispánicos, (Bajo del Coypar I) de aproximadamente 1000 ha. En un trabajo anterior se postuló que este amplio sistema de producción agrícola se originó hacia el final del proceso regional tardío (ca. 1300 AP) en asociación con el crecimient...

  13. Spin-Triplet Pairing State of Sr2RuO4 in the c-Axis Magnetic Field

    Science.gov (United States)

    Takamatsu, Shuhei; Yanase, Youichi

    2013-06-01

    We investigate the spin-triplet superconducting state of Sr2RuO4 in the magnetic field along the c-axis on the basis of the four-component Ginzburg--Landau (GL) model with a weak spin--orbit coupling. We consider superconducting states described by the d-vector parallel to the ab-plane (\\mbi{d}\\parallel ab), and find that three spin-triplet pairing states are stabilized in the magnetic field--temperature (H--T) phase diagram. Although a helical state is stable at low magnetic fields, a chiral II state is stabilized at high magnetic fields. A non-unitary spin-triplet pairing state appears near the transition temperature owing to the coupling of magnetic field and chirality. We elucidate synergistic and/or competing roles of the magnetic field, chirality, and spin--orbit coupling. It is shown that a fractional vortex lattice is stabilized in the chiral II phase owing to the spin--orbit coupling.

  14. Pyridine-2,6-diyl dinitroxides as room-temperature triplet ligands

    Energy Technology Data Exchange (ETDEWEB)

    Kawakami, Hinako; Tonegawa, Asato; Ishida, Takayuki, E-mail: takayuki.ishida@uec.ac.jp [Department of Engineering Science, The University of Electro-Communications, Tokyo (Japan)

    2016-02-01

    We have proposed tert-butyl 2-pyridyl nitroxide radicals as a promising paramagnetic chelating ligand, where the direct radical-metal bond leads to strong magnetic interaction. We successfully synthesized and isolated PyBN derivatives (pyridine-2,6-diyl bis(tert-butyl nitroxides)). The molecular and crystal structures of the target biradicals, MesPyBN, AntPyBN and tBuOPyBN were determined from the X-ray crystal structure analysis, which possess mesityl, 9-anthryl and tert-butoxy groups at the 5-position of the pyridine ring, respectively. The ground triplet state was characterized by means of SQUID susceptometry for each compound. On heating, the χ{sub m}T values of all the PyBN derivatives increased and reached a plateau at ca. 1.0 cm{sup 3} K mol{sup −1} at 300 K. It implies that biradicals behaved as triplet molecules even at room temperature, or 2J/k{sub B} >> 300 K. From the decay monitored in solution electron-spin resonance spectroscopy, MesPyBN was the most persistent, while tBuOPyBN was the most reactive, of the three.

  15. Pyridine-2,6-diyl dinitroxides as room-temperature triplet ligands

    Science.gov (United States)

    Kawakami, Hinako; Tonegawa, Asato; Ishida, Takayuki

    2016-02-01

    We have proposed tert-butyl 2-pyridyl nitroxide radicals as a promising paramagnetic chelating ligand, where the direct radical-metal bond leads to strong magnetic interaction. We successfully synthesized and isolated PyBN derivatives (pyridine-2,6-diyl bis(tert-butyl nitroxides)). The molecular and crystal structures of the target biradicals, MesPyBN, AntPyBN and tBuOPyBN were determined from the X-ray crystal structure analysis, which possess mesityl, 9-anthryl and tert-butoxy groups at the 5-position of the pyridine ring, respectively. The ground triplet state was characterized by means of SQUID susceptometry for each compound. On heating, the χmT values of all the PyBN derivatives increased and reached a plateau at ca. 1.0 cm3 K mol-1 at 300 K. It implies that biradicals behaved as triplet molecules even at room temperature, or 2J/kB >> 300 K. From the decay monitored in solution electron-spin resonance spectroscopy, MesPyBN was the most persistent, while tBuOPyBN was the most reactive, of the three.

  16. Strong electroweak phase transition from Supersymmetric Custodial Triplets

    CERN Document Server

    Garcia-Pepin, Mateo

    2016-01-01

    The Supersymmetric Custodial Triplet Model, a supersymmetric generalization of the Georgi-Machacek model, has proven to be an interesting modification of the MSSM. It extends the MSSM Higgs sector by three extra SU(2)L triplets in such a way that approximate custodial invariance is preserved and rho-parameter deviations are kept under control. By means of a sizeable triplet contribution to electroweak breaking the model is able to generate a barrier at tree level between the false vacuum and the electroweak one. This will result in a strong first order phase transition for an important region of the parameter space. We also look at the gravitational waves that could be generated as a result of the phase transition and show how future interferometers could be used as a probe of the model.

  17. Ion-Pair States in Triplet Molecular Hydrogen

    Science.gov (United States)

    Setzer, W.; Baker, B. C.; Ashman, S.; Morgan, T. J.

    2016-05-01

    An experimental search is underway to observe the long range triplet ionic states H+ H- of molecular hydrogen. Resonantly enhanced multi-photon ionization of the metastable c 3∏u- 2 pπ state is used access to the R(1)nd1 n = 21 Rydberg state that serves as an intermediate stepping stone state to probe the energy region above the ionization limit with a second tunable laser photon. The metastable state is prepared by electron capture of 6 keV H2+ions in potassium in a molecular beam. Formation of the H+ H- triplet configuration involves triplet excited states of the H- ion, especially the 2p23Pe state, the second bound state of H- predicted to exist with a lifetime long compared to typical auto ionization lifetimes but not yet observed experimentally. Details of the experiment and preliminary results to date will be presented at the conference.

  18. Leptogenesis, radiative neutrino masses and inert Higgs triplet dark matter

    CERN Document Server

    Lu, Wen-Bin

    2016-01-01

    We extend the standard model by three types of inert fields including Majorana fermion singlets/triplets, real Higgs singlets/triplets and leptonic Higgs doublets. In the presence of a softly broken lepton number and an exactly conserved Z_2 discrete symmetry, these inert fields together can mediate a one-loop diagram for a Majorana neutrino mass generation. The heavier inert fields can decay to realize a successful leptogenesis while the lightest inert field can provide a stable dark matter candidate. As an example, we demonstrate the leptogenesis by the inert Higgs doublet decays. We also perform a systematic study on the inert Higgs triplet dark matter scenario where the interference between the gauge and Higgs portal interactions can significantly affect the dark matter properties.

  19. Leptogenesis, radiative neutrino masses and inert Higgs triplet dark matter

    Science.gov (United States)

    Lu, Wen-Bin; Gu, Pei-Hong

    2016-05-01

    We extend the standard model by three types of inert fields including Majorana fermion singlets/triplets, real Higgs singlets/triplets and leptonic Higgs doublets. In the presence of a softly broken lepton number and an exactly conserved Z2 discrete symmetry, these inert fields together can mediate a one-loop diagram for a Majorana neutrino mass generation. The heavier inert fields can decay to realize a successful leptogenesis while the lightest inert field can provide a stable dark matter candidate. As an example, we demonstrate the leptogenesis by the inert Higgs doublet decays. We also perform a systematic study on the inert Higgs triplet dark matter scenario where the interference between the gauge and Higgs portal interactions can significantly affect the dark matter properties.

  20. Spin current due to triplet superconductor - ferromagnet interfaces

    International Nuclear Information System (INIS)

    The interface between a superconductor and a ferromagnet is an ideal setting in which to study the complicated interplay of these two phases. Although the relevant physics is now very well understood for a spin singlet pairing state of the superconductor, qualitatively new phenomena can appear for a spin triplet pairing state due to the intrinsic spin structure of the superconductor. One such surprising result is the existence of a bulk spin supercurrent in the triplet superconductor due to spin-flip reflection of triplet Cooper pairs at the superconductor-ferromagnet interface. The resulting spin current displays strong similarities to the spontaneous charge current in a conventional Josephson junction. The dependence of the spin current on a number of relevant parameters is studied e.g. the orbital pairing state of the superconductor and the exchange splitting of the ferromagnet. The possibility of unconventional dynamics of the magnetization of the ferromagnet is discussed.

  1. Lepton Flavor Violation in the singlet-triplet scotogenic model

    CERN Document Server

    Rocha-Moran, Paulina

    2016-01-01

    We investigate lepton flavor violation (LFV) in the the singlet-triplet scotogenic model in which neutrinos acquire non-zero masses at the 1-loop level. In contrast to the most popular variant of this setup, the singlet scotogenic model, this version includes a triplet fermion as well as a triplet scalar, leading to a scenario with a richer dark matter phenomenology. Taking into account results from neutrino oscillation experiments, we explore some aspects of the LFV phenomenology of the model. In particular, we study the relative weight of the dipole operators with respect to other contributions to the LFV amplitudes and determine the most constraining observables. We show that in large portions of the parameter space, the most promising experimental perspectives are found for LFV 3-body decays and for coherent $\\mu-e$ conversion in nuclei.

  2. Optimization of Spin-Triplet Supercurrent in Ferromagnetic Josephson Junctions

    Science.gov (United States)

    Klose, Carolin; Khaire, Trupti S.; Wang, Yixing; Pratt, W. P., Jr.; Birge, Norman O.; McMorran, B. J.; Ginley, T. P.; Borchers, J. A.; Kirby, B. J.; Maranville, B. B.; Unguris, J.

    2012-03-01

    We have observed long-range spin-triplet supercurrents in Josephson junctions containing ferromagnetic (F) materials, which are generated by noncollinear magnetizations between a central Co/Ru/Co synthetic antiferromagnet and two outer thin F layers. Here we show that the spin-triplet supercurrent is enhanced up to 20 times after our samples are subject to a large in-plane field. This occurs because the synthetic antiferromagnet undergoes a “spin-flop” transition, whereby the two Co layer magnetizations end up nearly perpendicular to the magnetizations of the two thin F layers. We report direct experimental evidence for the spin-flop transition from scanning electron microscopy with polarization analysis and from spin-polarized neutron reflectometry. These results represent a first step toward experimental control of spin-triplet supercurrents.

  3. Spin-lattice relaxation in phosphorescent triplet state molecules

    International Nuclear Information System (INIS)

    The present thesis contains the results of a study of spin-lattice relaxation (SLR) in the photo-excited triplet state of aromatic molecules, dissolved in a molecular host crystal. It appears that SLR in phosphorescent triplet state molecules often is related to the presence of so-called (pseudo) localized phonons in the molecular mixed crystals. These local phonons can be thought to correspond with vibrations (librations) of the guest molecule in the force field of the surrounding host molecules. Since the intermolecular forces are relatively weak, the frequencies corresponding with these vibrations are relatively low and usually are of the order of 10-30 cm-1. (Auth.)

  4. Effective t-J model of pairing: singlet versus triplet

    Directory of Open Access Journals (Sweden)

    J.Spałek

    2008-09-01

    Full Text Available The t-J model is regarded as a canonical model of spin-singlet pairing induced by the kinetic exchange interaction also responsible for an antiferromagnetic ordering in the strongly correlated narrow-band systems. In the orbitally degenerate systems both ferromagnetic and antiferromagnetic kinetic exchange interactions occur. I briefly review the analogy between the singlet and triplet types of pairing, as well as draw some general conclusions about the pairing induced by these exchange interactions. The general discussion is also illustrated with a concrete case of a two-dimensional lattice with the spin triplet pairing.

  5. Chromospheric Polarization in the Photospheric Solar Oxygen Infrared Triplet

    Science.gov (United States)

    Del Pino Alemán, Tanausú; Trujillo Bueno, Javier

    2015-07-01

    We present multilevel radiative transfer modeling of the scattering polarization observed in the solar O i infrared triplet around 777 nm. We demonstrate that the scattering polarization pattern observed on the solar disk forms in the chromosphere, far above the photospheric region where the bulk of the emergent intensity profiles originate. We investigate the sensitivity of the polarization pattern to the thermal structure of the solar atmosphere and to the presence of weak magnetic fields (10-2-100 G) through the Hanle effect, showing that the scattering polarization signals of the oxygen infrared triplet encode information on the magnetism of the solar chromosphere.

  6. Chromospheric Polarization in the Photospheric Solar Oxygen Infrared Triplet

    CERN Document Server

    Alemán, T del Pino

    2015-01-01

    We present multilevel radiative transfer modeling of the scattering polarization observed in the solar O I infrared triplet around 777 nm. We demonstrate that the scattering polarization pattern observed on the solar disk forms in the chromosphere, far above the photospheric region where the bulk of the emergent intensity profiles originates. We study the sensitivity of the polarization pattern to the thermal structure of the solar atmosphere and to the presence of weak magnetic fields (0.01 - 100 G) through the Hanle effect, showing that the scattering polarization signals of the oxygen infrared triplet encode information on the magnetism of the solar chromosphere.

  7. Spin-triplet supercurrent in planar geometry ferromagnetic Josephson junctions

    Science.gov (United States)

    Martinez, William M.; Pratt, W. P., Jr.; Birge, Norman O.

    2013-03-01

    The spin-triplet supercurrent in ferromagnetic Josephson junctions is obtained by surrounding the central ferromagnet with noncollinear ferromagnetic layers, F'. In metallic ferromagnets, the long-range nature of the spin-triplet supercurrent has only been tested to lengths of a few tens of nm. In this work, we are fabricating and measuring S/F'/F/F'/S junctions where the central F layer has a lateral geometry with lengths up to a few hundred nm. We will report on our recent progress. Supported by the DOE under grant DE-FG-02-06ER46341.

  8. A CP-violating phase in a two Higgs triplet scenario : some phenomenological implications

    CERN Document Server

    Chaudhuri, Avinanda

    2016-01-01

    We consider a scenario where, along with the usual Higgs doublet, two scalar triplets are present. The extension of the triplet sector is required for the Type~II mechanism for the generation of neutrino masses, if this mechanism has to generate a neutrino mass matrix with two-zero texture. One CP-violating phase has been retained in the scalar potential of the model, and all parameters have been chosen consistently with the observed neutrino mass and mixing patterns. We find that a large phase ($\\gtrsim 60^{\\circ}$) splits the two doubly-charged scalar mass eigenstates wider apart, so that the decay $H_1^{++} \\rightarrow H_2^{++} h$ is dominant (with h being the $125$ GeV scalar). We identify a set of benchmark points where this decay dominates. This is complementary to the situation, reported in our earlier work, where the heavier doubly-charged scalar decays as $H_1^{++} \\rightarrow H_2^+ W^+$. We point out the rather spectacular signal, ensuing from $H_1^{++} \\rightarrow H_2^{++} h$, in the form of Higgs ...

  9. C P -violating phase in a two Higgs triplet scenario: Some phenomenological implications

    Science.gov (United States)

    Chaudhuri, Avinanda; Mukhopadhyaya, Biswarup

    2016-05-01

    We consider a scenario where, along with the usual Higgs doublet, two scalar triplets are present. The extension of the triplet sector is required for the Type II seesaw mechanism for the generation of neutrino masses, if this mechanism has to generate a neutrino mass matrix with two-zero texture. One C P -violating phase has been retained in the scalar potential of the model, and all parameters have been chosen consistently with the observed neutrino mass and mixing patterns. We find that a large phase (≳6 0 ° ) splits the two doubly charged scalar mass eigenstates wider apart, so that the decay H1++→H2++h is dominant (with h being the 125 GeV scalar). We identify a set of benchmark points where this decay dominates. This is complementary to the situation, reported in our earlier work, where the heavier doubly charged scalar decays as H1++→H2+W+ . We point out the rather spectacular signal, ensuing from H1++→H2++h , in the form of Higgs plus the same-sign dilepton peak, which can be observed at the Large Hadron Collider.

  10. Deriving Metallicities From the Integrated Spectra of Extragalactic Globular Clusters Using the Near-Infrared Calcium Triplet

    CERN Document Server

    Foster, Caroline; Proctor, Robert N; Strader, Jay; Brodie, Jean P; Spitler, Lee R

    2010-01-01

    The Ca triplet (CaT) feature in the near-infrared has been employed as a metallicity indicator for individual stars as well as integrated light of Galactic globular clusters (GCs) and galaxies with varying degrees of success, and sometimes puzzling results. Using the DEIMOS multi-object spectrograph on Keck we obtain a sample of 144 integrated light spectra of GCs around the brightest group galaxy NGC 1407 to test whether the CaT index can be used as a metallicity indicator for extragalactic GCs. Different sets of single stellar population models make different predictions for the behavior of the CaT as a function of metallicity. In this work, the metallicities of the GCs around NGC 1407 are obtained from CaT index values using an empirical conversion. The measured CaT/metallicity distributions show unexpected features, the most remarkable being that the brightest red and blue GCs have similar CaT values despite their large difference in mean color. Suggested explanations for this behavior in the NGC 1407 GC ...

  11. Stability of singlet and triplet trions in carbon nanotubes

    DEFF Research Database (Denmark)

    Rønnow, Troels Frimodt; Pedersen, Thomas Garm; Cornean, Horia

    2009-01-01

    We investigate singlet and triplet trion states in semiconducting carbon nanotubes using a one-dimensional model. It is concluded that singlet trion states in bind up to 13.5% stronger than exciton states, and that they lower the optical transition energy with up to 50% of the tight binding band...

  12. Dark Matter from the Supersymmetric Custodial Triplet Model

    CERN Document Server

    Delgado, Antonio; Ostdiek, Bryan; Quiros, Mariano

    2015-01-01

    The Supersymmetric Custodial Triplet Model (SCTM) adds to the particle content of the MSSM three $SU(2)_L$ triplet chiral superfields with hypercharge $Y=(0,\\pm1)$. At the superpotential level the model respects a global $SU(2)_L \\otimes SU(2)_R$ symmetry only broken by the Yukawa interactions. The pattern of vacuum expectation values of the neutral doublet and triplet scalar fields depends on the symmetry pattern of the Higgs soft breaking masses. We study the cases where this symmetry is maintained in the Higgs sector, and when it is broken only by the two doublets attaining different vacuum expectation values. In the former case, the symmetry is spontaneously broken down to the vectorial subgroup $SU(2)_V$ and the $\\rho$ parameter is protected by the custodial symmetry. However in both situations the $\\rho$ parameter is protected at tree level, allowing for light triplet scalars with large vacuum expectation values. We find that over a large range of parameter space, a light neutralino can supply the corre...

  13. Odd-Frequency Triplet Josephson Current Through an Exchange Spring

    Science.gov (United States)

    Bill, Andreas; Baker, Thomas E.; Richie-Halford, Adam; Moke, Adam K.

    2013-03-01

    The existence of an odd-frequency long range triplet component in the order parameter of a proximity system with singlet superconductors is a recent prediction that has garnered great interest. The experimental fingerprint of this phenomenon is difficult to establish. We investigate a hybrid structure in which the emergence of the long range triplet component may be measured and identified. We consider a superconductor - exchange spring - superconductor Josephson junction as a function of increasing twist of the magnetic domain wall in the exchange spring. We show that as the domain wall is generated the long range triplet component emerges and modifies the current flowing through the Josephson junction. The critical temperature is also affected by the increased twist of the domain wall. The calculations lead us to propose an experiment where the long range triplet component can unequivocally be identified. We gratefully acknowledge the support of the National Science Foundation (DMR-0907242), the Army Research Laboratory, the Research Corporation, the Graduate Research Fellowship and RSCA at CSU Long Beach.

  14. Spin-triplet supercurrent in Co-based Josephson junctions

    International Nuclear Information System (INIS)

    In the past year several groups have reported experimental evidence for spin-triplet supercurrents in Josephson junctions containing strong ferromagnetic materials. In this paper we present several new experimental results that follow up on our previous work. We study Josephson junctions of the form S/X/N/SAF/N/X/S, where S is a superconductor (Nb), N is a normal metal, SAF is a synthetic antiferromagnet of the form Co/Ru/Co and X is an ferromagnetic layer necessary to induce spin-triplet correlations in the structure. Our work is distinguished by the fact that the generation of spin-triplet correlations is tuned by the type and thickness of the X layers. The most important new result reported here is the discovery that a conventional, strong ferromagnetic material, Ni, performs well as the X layer, if it is sufficiently thin. This discovery rules out our earlier hypothesis that out-of-plane magnetocrystalline anisotropy is an important attribute of the X layers. These results suggest that the spin-triplet correlations are most likely induced by noncollinear magnetization between the X layers and adjacent Co layers.

  15. Spin-triplet supercurrent in Co-based Josephson junctions

    Energy Technology Data Exchange (ETDEWEB)

    Khasawneh, Mazin A; Khaire, Trupti S; Klose, Carolin; Pratt, William P Jr; Birge, Norman O, E-mail: birge@pa.msu.edu [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824-2320 (United States)

    2011-02-15

    In the past year several groups have reported experimental evidence for spin-triplet supercurrents in Josephson junctions containing strong ferromagnetic materials. In this paper we present several new experimental results that follow up on our previous work. We study Josephson junctions of the form S/X/N/SAF/N/X/S, where S is a superconductor (Nb), N is a normal metal, SAF is a synthetic antiferromagnet of the form Co/Ru/Co and X is an ferromagnetic layer necessary to induce spin-triplet correlations in the structure. Our work is distinguished by the fact that the generation of spin-triplet correlations is tuned by the type and thickness of the X layers. The most important new result reported here is the discovery that a conventional, strong ferromagnetic material, Ni, performs well as the X layer, if it is sufficiently thin. This discovery rules out our earlier hypothesis that out-of-plane magnetocrystalline anisotropy is an important attribute of the X layers. These results suggest that the spin-triplet correlations are most likely induced by noncollinear magnetization between the X layers and adjacent Co layers.

  16. Spin-triplet supercurrent in Co-based Josephson junctions

    Science.gov (United States)

    Khasawneh, Mazin A.; Khaire, Trupti S.; Klose, Carolin; Pratt, William P., Jr.; Birge, Norman O.

    2011-02-01

    In the past year several groups have reported experimental evidence for spin-triplet supercurrents in Josephson junctions containing strong ferromagnetic materials. In this paper we present several new experimental results that follow up on our previous work. We study Josephson junctions of the form S/X/N/SAF/N/X/S, where S is a superconductor (Nb), N is a normal metal, SAF is a synthetic antiferromagnet of the form Co/Ru/Co and X is an ferromagnetic layer necessary to induce spin-triplet correlations in the structure. Our work is distinguished by the fact that the generation of spin-triplet correlations is tuned by the type and thickness of the X layers. The most important new result reported here is the discovery that a conventional, strong ferromagnetic material, Ni, performs well as the X layer, if it is sufficiently thin. This discovery rules out our earlier hypothesis that out-of-plane magnetocrystalline anisotropy is an important attribute of the X layers. These results suggest that the spin-triplet correlations are most likely induced by noncollinear magnetization between the X layers and adjacent Co layers.

  17. Stability of singlet and triplet trions in carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Ronnow, Troels F. [Department of Physics and Nanotechnology, Skjernvej 4C, 9220 Aalborg Ost (Denmark)], E-mail: tfr@nanophysics.dk; Pedersen, Thomas G. [Department of Physics and Nanotechnology, Skjernvej 4C, 9220 Aalborg Ost (Denmark)], E-mail: tgp@nano.aau.dk; Cornean, Horia D. [Department of Mathematical Sciences, Frederik Bajers Vej 7G, 9220 Aalborg Ost (Denmark)], E-mail: cornean@math.aau.dk

    2009-04-06

    We investigate singlet and triplet trion states in semiconducting carbon nanotubes using a one-dimensional model. It is concluded that singlet trion states in bind up to 13.6% stronger than exciton states, and that they lower the optical transition energy with up to 50% of the tight binding band gap energy.

  18. Stability of singlet and triplet trions in carbon nanotubes

    International Nuclear Information System (INIS)

    We investigate singlet and triplet trion states in semiconducting carbon nanotubes using a one-dimensional model. It is concluded that singlet trion states in bind up to 13.6% stronger than exciton states, and that they lower the optical transition energy with up to 50% of the tight binding band gap energy.

  19. Triplet states at an O vacancy in alpha-quartz

    DEFF Research Database (Denmark)

    Lægsgaard, Jesper

    2002-01-01

    The energy landscape of an alpha-quartz O vacancy in the lowest triplet state is investigated. Four local minima are identified and geometries, total energies, and electron paramagnetic resonance (EPR) parameters are obtained. On the basis of calculated values for the magnetic dipole interaction...

  20. CA 242, a new tumour marker for pancreatic cancer: a comparison with CA 19-9, CA 50 and CEA.

    OpenAIRE

    Haglund, C.; Lundin, J; Kuusela, P.; Roberts, P. J.

    1994-01-01

    The serum expression of a novel tumour marker, CA 242, defined by monoclonal antibody C 242, was studied in 179 patients with pancreatic cancer. The results were compared with CA 19-9, CA 50 and CEA. CA 242 is a carbohydrate closely related, but not identical, to CA 19-9 and CA 50. The overall sensitivity of the CA 242 assay was 74%: 55% in stage I, 83% in stage II-III and 78% in stage IV disease. The specificity calculated from 112 patients with benign diseases was 91%. CA 19-9 had a higher ...

  1. Precision spectroscopy with ultracold 87Rb2 triplet molecules

    International Nuclear Information System (INIS)

    In this thesis I report precision spectroscopy with ultracold 87Rb2 triplet molecules where we use lasers to couple the states in different molecular potentials. We study in detail states of the a 3 sum +u and (1) 3 sum +g potentials. These states are of great importance for transferring weakly bound molecules to the ro-vibrational triplet ground state via states of the excited potential. As most experiments start from molecules in their X 1 sum +g ground state, the triplet states were hard to access via dipole transitions and remained largely unexplored. The measurements presented in this thesis are the first detailed study of diatomic 87Rb2 molecules in these states. Our experiments start with an ultracold cloud of 87Rb atoms. We then load this cloud into an optical lattice where we use a magnetic Feshbach resonance at 1007.4 G to perform a Feshbach association. After we have removed all unbound atoms, we end up with a pure sample of weakly bound Feshbach molecules inside the optical lattice. The optical lattice prevents these molecules from colliding with each other which results in molecular lifetimes on the order of a few hundred milliseconds. In the first set of experiments, we use a laser coupling the Feshbach state to the excited (1) 3 sum +g triplet state to map out its low-lying vibrational (v = 0.. 15), rotational, hyperfine, and Zeeman structure. The experimental results are in good agreement with calculations done by Marius Lysebo and Prof. Leif Veseth. We then map out in detail the vibrational, rotational, hyperfine, and Zeeman structure of the a 3 sum +u triplet ground state using dark state spectroscopy with levels in the (1) 3 sum +g potential as an intermediate state. In this scheme we are able to access molecules in triplet states because our Feshbach state has strong triplet character. Interestingly, it happens that some deeply bound states which belong to the X 1 sum +g potential are close to levels in the a 3 sum +u potential. In these cases

  2. Calcium transport in sealed vesicles from red beet (Beta vulgaris L.) storage tissue. II. Characterization of 45Ca2+ uptake into plasma membrane vesicles

    International Nuclear Information System (INIS)

    Calcium uptake was examined in sealed plasma membrane vesicles isolated from red beet (Beta vulgaris L.) storage tissue using 45Ca2+. Uptake of 45Ca2+ by the vesicles was ATP-dependent and radiotracer accumulated by the vesicles could be released by the addition of the calcium ionophore A23187. The uptake was stimulated by gramicidin D but slightly inhibited by carbonylcyanide m-chlorophenylhydrazone. Although the latter result might suggest some degree of indirect coupling of 45Ca2+ uptake to ATP utilization via ΔμH+, no evidence for a secondary H+/Ca2+ antiport in this vesicle system could be found. Following the imposition of an acid-interior pH gradient, proton efflux from the vesicle was not enhanced by the addition of Ca2+ and an imposed pH gradient could not drive 45Ca2+ uptake. Optimal uptake of 45Ca2+ occurred broadly between pH 7.0 and 7.5 and the transport was inhibited by orthovanadate, N,N'-dicyclohexylcarbodiimide, and diethylstilbestrol but insensitive to nitrate and azide. The dependence of 45Ca2+ uptake on both calcium and Mg:ATP concentration demonstrated saturation kinetics with K/sub m/ values of 6 micromolar and 0.37 millimolar, respectively. While ATP was the preferred substrate for driving 45Ca2+ uptake, GTP could drive transport at about 50% of the level observed for ATP. The results of this study demonstrate the presence of a unique primary calcium transport system associated with the plasma membrane which could drive calcium efflux from the plant cell

  3. Calcium transport in sealed vesicles from red beet (Beta vulgaris L. ) storage tissue. II. Characterization of /sup 45/Ca/sup 2 +/ uptake into plasma membrane vesicles

    Energy Technology Data Exchange (ETDEWEB)

    Giannini, J.L.; Ruiz-Cristin, J.; Briskin, D.P.

    1987-12-01

    Calcium uptake was examined in sealed plasma membrane vesicles isolated from red beet (Beta vulgaris L.) storage tissue using /sup 45/Ca/sup 2 +/. Uptake of /sup 45/Ca/sup 2 +/ by the vesicles was ATP-dependent and radiotracer accumulated by the vesicles could be released by the addition of the calcium ionophore A23187. The uptake was stimulated by gramicidin D but slightly inhibited by carbonylcyanide m-chlorophenylhydrazone. Although the latter result might suggest some degree of indirect coupling of /sup 45/Ca/sup 2 +/ uptake to ATP utilization via ..delta mu..H/sup +/, no evidence for a secondary H/sup +//Ca/sup 2 +/ antiport in this vesicle system could be found. Following the imposition of an acid-interior pH gradient, proton efflux from the vesicle was not enhanced by the addition of Ca/sup 2 +/ and an imposed pH gradient could not drive /sup 45/Ca/sup 2 +/ uptake. Optimal uptake of /sup 45/Ca/sup 2 +/ occurred broadly between pH 7.0 and 7.5 and the transport was inhibited by orthovanadate, N,N'-dicyclohexylcarbodiimide, and diethylstilbestrol but insensitive to nitrate and azide. The dependence of /sup 45/Ca/sup 2 +/ uptake on both calcium and Mg:ATP concentration demonstrated saturation kinetics with K/sub m/ values of 6 micromolar and 0.37 millimolar, respectively. While ATP was the preferred substrate for driving /sup 45/Ca/sup 2 +/ uptake, GTP could drive transport at about 50% of the level observed for ATP. The results of this study demonstrate the presence of a unique primary calcium transport system associated with the plasma membrane which could drive calcium efflux from the plant cell.

  4. Resonance raman and absorption spectra of isomeric retinals in their lowest excited triplet states

    DEFF Research Database (Denmark)

    Wilbrandt, Robert Walter; Jensen, N.-H.; Houee-Levin, C.

    1985-01-01

    The triplet-triplet absorption spectra of 9-cis and all-trans-retinal as well as the time-resolved resonance Raman spectra of the lowest electronically excited triplet states of 9-cis-, 11-cis, 13-cis and all-trans-retinal in aromatic solvents at room temperature were obtained under conditions en...

  5. Modeling of sorption enhanced steam methane reforming—Part II: Simulation within a novel Ca/Cu chemical loop process for hydrogen production

    OpenAIRE

    Fernández García, José Ramón; Abanades García, Juan Carlos; Grasa Adiego, Gemma

    2012-01-01

    The initial stage of a novel Ca/Cu looping process for hydrogen production that involves the sorption enhanced reforming of methane (SER) at high pressure and at a moderate temperature is simulated using a mathematical model developed in Part I of this work. The SER reaction step has been analyzed under dynamic conditions within the framework of the following reactor parameters and operation conditions: catalyst/sorbent ratio, space time, operating temperature, operating pressure and steam/ca...

  6. 750-GeV Diphoton Resonance as the Singlet of Custodial Higgs Triplet Model

    CERN Document Server

    Chiang, Cheng-Wei

    2016-01-01

    The observation of diphoton excess around the mass of 750~GeV at the LHC motivates us to consider the singlet Higgs boson in the custodial Higgs triplet model as a good candidate. Based on an earlier study of comprehensive parameter scan for viable mass spectra, we show that the diphoton resonance data fall well within the allowed space. Moreover, we point out that a definite mass hierarchy emerges among the exotic Higgs bosons in the model. Further search channels for the singlet and those for the other exotic Higgs bosons in LHC Run-II are discussed. In particular, we present a simulation of distributions of two kinematic variables for the search of the doubly-charged Higgs boson.

  7. Heats of Formation of Triplet Ethylene, Ethylidene, and Acetylene

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, M.T.; Matus, M.H.; Lester Jr, W.A.; Dixon, David A.

    2007-06-28

    Heats of formation of the lowest triplet state of ethylene and the ground triplet state of ethylidene have been predicted by high level electronic structure calculations. Total atomization energies obtained from coupled-cluster CCSD(T) energies extrapolated to the complete basis set limit using correlation consistent basis sets (CBS), plus additional corrections predict the following heats of formation in kcal/mol: Delta H0f(C2H4,3A1) = 80.1 at 0 K and 78.5 at 298 K, and Delta H0f(CH3CH,3A") = 86.8 at 0 K and 85.1 at 298 K, with an error of less than +-1.0 kcal/mol. The vertical and adiabatic singlet-triplet separation energies of ethylene were calculated as Delta ES-T,vert = 104.1 and Delta ES-T,adia = 65.8 kcal/mol. These results are in excellent agreement with recent quantum Monte Carlo (DMC) values of 103.5 +- 0.3 and 66.4 +- 0.3 kcal/mol. Both sets of computational values differ from the experimental estimate of 58 +- 3 kcal/mol for the adiabatic splitting. The computed singlet-triplet gap at 0 K for acetylene is Delta ES-T,adia(C2H2) = 90.5 kcal/mol, which is in notable disagreement with the experimental value of 82.6 kcal/mol. The heat of formation of the triplet is Delta H0f(C2H2,3B2) = 145.3 kcal/mol. There is a systematic underestimation of the singlet-triplet gaps in recent photodecomposition experiments by ~;;7 to 8 kcal/mol. For vinylidene, we predict Delta H0f(H2CC,1A1) = 98.8 kcal/mol at 298 K (exptl. 100.3 +- 4.0), Delta H0f(H2CC,3B2) = 146.2 at 298 K, and an energy gap Delta ES-T-adia(H2CC) = 47.7 kcal/mol.

  8. Zero-field splitting of the ground and excited triplet states of 2-naphthylphenylcarbene studied by hole-burning on triplet-triplet fluorescence excitation spectra

    Science.gov (United States)

    Kozankiewicz, B.; Bernard, J.; Migirdicyan, E.; Orrit, M.; Platz, M. S.

    1995-11-01

    Spectral holes were burned in the two main lines of the triplet-triplet 0-0 fluorescence excitation spectrum of 2-napththylphenylcarbene in n-hexane at 1.8 K. For the line assigned to pseudo-E/trans conformer, the central hole at the frequency of burning light has several narrow components separated by 0.3 ± 0.05 and 1.0 ± 0.1 GHz and a satellite doublet line on the low energy side, 14.5 ± 0.5 and 15.5 ± 0.5 GHz away. For the line assigned to the psuedo-Z/cis conformer, the central hole is accompanied by holes burned on the low energy side, 0.8 ± 0.1, 5.2 ± 0.1, 11.9 ± 0.1 and 16.2 ± 0.1 GHz away. The hole-burning pattern is explained by a model taking into account the zero-field splitting (ZFS) of the ground T 0 and excited T 1 triplet states as well as the selectivity of excitation relaxation by the intersystem crossing channel. Analysis provides information about the ZFS parameters of the T 1 state. For the pseudo-E/trans 2-NPC they are: D0 = 0.47 ± 0.02 cm -1, E0 = 0.017 ± 0.003 cm -1, D1 = 0.038 ± 0.003 cm -1 and E1 = 0.005 ± 0.001 cm -1.

  9. Influence of Ca/Mg ratio on phytoextraction properties of Salix viminalis. II. Secretion of low molecular weight organic acids to the rhizosphere.

    Science.gov (United States)

    Magdziak, Z; Kozlowska, M; Kaczmarek, Z; Mleczek, M; Chadzinikolau, T; Drzewiecka, K; Golinski, P

    2011-01-01

    A hydroponic experiment in a phytotron was performed to investigate the effect of two different Ca/Mg ratios (4:1 and 1:10) and trace element ions (Cd, Cu, Pb and Zn) in solution on the efficiency of low molecular weight organic acid (LMWOA) formation in Salix viminalis rhizosphere. Depending on the Ca/Mg ratio and presence of selected trace elements at 0.5mM concentration, the amount and kind of LMWOAs in the rhizosphere were significantly affected. In physiological 4:1 Ca/Mg ratio the following complex of acids was observed: malonic (Pb, Zn), citric, lactic, maleic and succinic (Zn) acids. Under 1:10 Ca/Mg ratio, citric (Cd, Zn), maleic and succinic (Cd, Cu, Pb, Zn) acids were seen. Additionally, high accumulation of zinc and copper in all systems was observed, with the exception of those where one of the metals was at higher concentration. Summing up, the results indicate a significant role of LMWOAs in Salix phytoremediation abilities. Both effects can be modulated depending on the mutual Ca/Mg ratio. PMID:20950858

  10. Study on the competition between density waves, singlet, and triplet pairing superconductivity in an organic conductor (TMTSF)2PF6

    International Nuclear Information System (INIS)

    We study the effect of the dimerization of molecules and the effect of magnetic field on the phase competition in quasi-one-dimensional organic superconductors (TMTSF)2X by applying the random phase approximation method. We conclude the following: (i) Due to the decrease of the dimerization, which corresponds to applying the pressure and cooling, spin and charge density wave states are suppressed and give way to a superconducting state. (ii) Applying the magnetic field favors the spin triplet f-wave pairing with spins parallel to the magnetic field due to the cooperation between the magnetic field and the long range off-site interactions

  11. On-chip generation of photon-triplet states.

    Science.gov (United States)

    Krapick, Stephan; Brecht, Benjamin; Herrmann, Harald; Quiring, Viktor; Silberhorn, Christine

    2016-02-01

    Efficient sources of many-partite non-classical states are key for the advancement of quantum technologies and for the fundamental testing of quantum mechanics. We demonstrate the generation of time-correlated photon triplets at telecom wavelengths via pulsed cascaded parametric down-conversion in a monolithically integrated source. By detecting the generated states with success probabilities of (6.25 ± 1.09) × 10(-11) per pump pulse at injected powers as low as 10 μW, we benchmark the efficiency of the complete system and deduce its high potential for scalability. Our source is unprecedentedly long-term stable, it overcomes interface losses intrinsically due to its monolithic architecture, and the photon-triplet states dominate uncorrelated noise significantly. These results mark crucial progress towards the proliferation of robust, scalable, synchronized and miniaturized quantum technology. PMID:26906852

  12. The N = 1 Triplet Vertex Operator Superalgebras: Twisted Sector

    Directory of Open Access Journals (Sweden)

    Drazen Adamovic

    2008-12-01

    Full Text Available We classify irreducible σ-twisted modules for the N = 1 super triplet vertex operator superalgebra SW(m introduced recently [Adamovic D., Milas A., Comm. Math. Phys., to appear, arXiv:0712.0379]. Irreducible graded dimensions of σ-twisted modules are also determined. These results, combined with our previous work in the untwisted case, show that the SL(2,Z-closure of the space spanned by irreducible characters, irreducible supercharacters and σ-twisted irreducible characters is (9m + 3-dimensional. We present strong evidence that this is also the (full space of generalized characters for SW(m. We are also able to relate irreducible SW(m characters to characters for the triplet vertex algebra W(2m + 1, studied in [Adamovic D., Milas A., Adv. Math. 217 (2008, 2664-2699, arXiv:0707.1857].

  13. Triplet Josephson current modulated by Rashba spin-orbit coupling

    International Nuclear Information System (INIS)

    We study the Rashba spin-orbit coupling (RSOC) effect on the supercurrent in a clean triplet superconductor/two-dimensional electron gas/triplet superconductor (TS/2DEG/TS) junction, where RSOC is considered in the 2DEG region. Based on the Bogoliubov-de Gennes equation and quantum scattering method, we show that RSOC can lead to a 0-π oscillation of supercurrent and the abrupt current reversal effect. The current direction can be reversed by a tiny modulation of RSOC, and this is attributed to the equal spin pairing of the TS order parameter and the spin precession phase of the quasiparticle traveling in the RSOC region. The RSOC strength can be controlled by an electric field in experiments, thus our findings provide a purely electric means to modulate the supercurrent in TS Josephson junctions.

  14. Señalización de Ca2+intracelular en endotelio in situ de aorta de rata con diabetes mellitus tipo II

    OpenAIRE

    Paredes Juárez, Genaro Alberto

    2008-01-01

    La diabetes mellitus es la primera causa de muerte en nuestro país, debido a las alteraciones que provoca en la función y estructura de los vasos sanguíneos, aumentando el riesgo de hipertensión, infarto miocárdico y derrame cerebral. Las alteraciones vasculares se han correlacionado con disfunción endotelial. La señal de Ca2+ es un mecanismo clave en la función de las actividades endoteliales. A la fecha no se cuenta con información respecto a la señalización de Ca2+ en ...

  15. Ultrafast photogeneration mechanisms of triplet states in para-hexaphenyl

    OpenAIRE

    Zenz, C.; Cerullo, G.; G. Lanzani; Graupner, W.; Meghdadi, F.; Leising, G.; Silvestri, S

    1999-01-01

    We present femtosecond pump-probe measurements, both conventional and electric field-assisted, on organic light-emitting devices based on para-hexaphenyl. The dominant triplet excition generation mechanism is assigned to nongeminate bimolecular recombination of photogenerated, spin-1/2 polarons. This process is active within a few hundred femtoseconds after photoexcitation and involves about 20% of the initially excited states. At higher photoexcitation densities, we observe an additional tri...

  16. Substrate Integrated Waveguide Diplexer Based on Circular Triplet Combline Filters

    OpenAIRE

    Sirci, Stefano; Martínez Pérez, Jorge Daniel; Vague Cardona, José Joaquín; Boria Esbert, Vicente Enrique

    2015-01-01

    The design of substrate integrated waveguide (SIW) diplexers, based on combline triplet sections with transmission zeros (TZs) placed below and above the passband, is presented. In order to control the location of the TZs, positive and negative couplings are conveniently provided. A highly compact implementation based on circular substrate integrated coaxial resonators is proposed. An X band diplexer with channel center frequencies at 9.5 and 10.5 GHz and absolute bandwidths of 400 MHz is ...

  17. Conjoined Twins in a Triplet Pregnancy: A Case Report

    OpenAIRE

    Smith, Graeme N.; Shepherd, Lynn J.

    2011-01-01

    Background. Conjoined twins are a rare complication of monozygotic twinning and are associated with high perinatal mortality. Case. Here we present a case of conjoined twins in a triplet pregnancy diagnosed at 13 of weeks gestation. With the aid of 3D ultrasound and MRI images, the parents were counseled regarding the management options, including continuation of pregnancy, termination of pregnancy, or selective fetocide. They chose selective fetocide of the conjoined twins and went on to del...

  18. Correlation-induced triplet superconductivity on the graphene lattice

    OpenAIRE

    Sahebsara, Peyman; Senechal, David

    2009-01-01

    We investigate the possibility of superconductivity on the graphene lattice within the repulsive Hubbard model using the variational cluster approximation (VCA). We find that singlet superconductivity is impossible; instead, triplet superconductivity is favored, with four solutions that are close to each other in energy and differ by their symmetry; one is f-wave, the other three p-wave, including a p+ip solution that breaks time-reversal invariance.

  19. Anomalous Josephson Hall effect in magnet/triplet superconductor junctions

    OpenAIRE

    Yokoyama, Takehito

    2015-01-01

    We investigate anomalous Hall effect in a magnet coupled to a triplet superconductor under phase gradient. It is found that the anomalous Hall supercurrent arises from non-trivial structure of the magnetization. The magnetic structure manifested in the Hall supercurrent is characterized by even order terms of the exchange coupling, essentially different from that discussed in the context of anomalous Hall effect, reflecting the disspationless nature of supercurrent. We also discuss a possible...

  20. Cascade Decays of Triplet Higgs Bosons at LEP2

    CERN Document Server

    Akeroyd, A G

    1998-01-01

    We study the Georgi-Machacek two triplet, one doublet model in the context of LEP2, and show that cascade decays of Higgs bosons to lighter Higgs bosons and a virtual vector boson may play a major role. Such decays would allow the Higgs bosons of this model to escape current searches, and in particular are of great importance for the members of the five-plet which will always decay to the three-plet giving rise to cascade signatures.

  1. Genome-specificity of triplet periodicity of prokaryotic genomes

    International Nuclear Information System (INIS)

    Authors have found that triplet periodicity (TP) is more similar inside genome than between genomes and that TP distribution inside genome corresponds to hypothesis which imply common TP pattern for majority of sequences inside a genome. To test the specificity of TP, the classification of the gene has been carried out to detect the belonging to one genome of the pair. For most pairs, the classification accuracy was more than 85%

  2. Signatures of Dark Matter in Inert Triplet Models

    CERN Document Server

    Araki, Takeshi; Nagao, Keiko I

    2011-01-01

    In this talk, we will review the signatures of dark matter in two inert triplet models. For the first model with the hypercharge Y=0, the dark matter mass around 5.5 TeV is favored by both the WMAP data and the direct detection. In contrast, for the second model of Y=2, it is excluded by the direct detection experiments although dark matter with its mass around 2.8 TeV is allowed by WMAP.

  3. Synthesis, measurements, and theoretical analysis of carbazole derivatives with high-triplet-energy

    Energy Technology Data Exchange (ETDEWEB)

    Li Jianli; Mi Xiaoyun; Wan Yuchun [School of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022 (China); Si Zhenjun, E-mail: szj@cust.edu.cn [School of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022 (China); Institute of Organic Chemistry and Biochemistry, Czech Academy of Science, Praha 6 16610 (Czech Republic); Sun Haiying; Duan Qian [School of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022 (China); He Xingquan [School of Chemistry and Environmental Engineering, Changchun University of Science and Technology, Changchun 130022 (China); Yan Dong; Wan Sha [School of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022 (China)

    2012-05-15

    In order to obtain the blue light-emitting organic materials with high triplet state energy, two 3,5-diphenyl-4H-1,2,4-triazole (Tz) containing carbazole (Cz) derivatives of 9-(4-(3,5-diphenyl-4H-1,2,4-triazol-4-yl)phenyl)-9H-carbazole (TzCz1) and 3,6-di-tert-butyl-9-(4-(3,5-diphenyl-4H-1,2,4-triazol-4-yl)phenyl) -9H-carbazole (TzCz2) are synthesized using Cz acting as the starting material, as well as characterized by the {sup 1}H NMR spectra, ultraviolet-visible (UV-vis) absorption spectra, and the IR absorption spectra. The luminescence quantum yields (LQYs) of TzCz1 and TzCz2 are measured in CH{sub 2}Cl{sub 2} solution to be 32.1% and 47.5%, respectively. The electrochemical analysis and the photophysical measurements suggest that the triplet energy levels and the energy gaps of the highest-occupied orbital and the lowest-unoccupied orbital are 2.83 eV and 3.59 eV for TzCz1, and 2.80 eV and 3.43 eV for TzCz2. At last, the theoretical analyses of their ground state geometries and the simulated UV-vis absorption spectra are carried out at B3LYP1/6-31G Low-Asterisk level. The studies mentioned above indicate that both TzCz1 and TzCz2 are suitable for the host materials of blue light-emitting diodes. - Highlights: Black-Right-Pointing-Pointer Synthesis of two blue light-emitting Carbazole derivatives. Black-Right-Pointing-Pointer Photophysical and electrochemical properties are systematically studied. Black-Right-Pointing-Pointer Theoretical analysis of geometry of the ground states and the UV-vis absorption are performed with Firefly package. Black-Right-Pointing-Pointer The triplet energy levels are measured to be ca. 2.83 eV.

  4. Supersymmetric Custodial Higgs Triplets and the Breaking of Universality

    CERN Document Server

    Garcia-Pepin, Mateo; Quiros, Mariano; Vega, Roberto; Vega-Morales, Roberto; Yu, Tien-Tien

    2014-01-01

    Higgs triplet models are known to have difficulties obtaining agreement with electroweak precision data and in particular constraints on the $\\rho$ parameter. Either a global $SU(2)_L \\otimes SU(2)_R$ symmetry has to be imposed on the scalar potential at the electroweak scale, as done in the well-known Georgi-Machacek (GM) model, or the triplet vacuum expectation values must be very small. We construct a supersymmetric model that can satisfy constraints on the $\\rho$ parameter, even if these two conditions are not fulfilled. We supersymmetrize the GM model by imposing the $SU(2)_L \\otimes SU(2)_R$ symmetry at a scale $\\mathcal M$, which we argue should be at or above the messenger scale, where supersymmetry breaking is transmitted to the observable sector. We show that scales $\\mathcal M$ well above 100 TeV and sizable contributions from the triplets to electroweak symmetry breaking can be comfortably accommodated. We discuss the main phenomenological properties of the model and demonstrate that the departure...

  5. Sirenomelia in a Nigerian triplet: a case report

    Directory of Open Access Journals (Sweden)

    Wonodi Woroma

    2011-09-01

    Full Text Available Abstract Introduction Sirenomelia, also known as mermaid syndrome, is a very rare fatal congenital abnormality in which the legs are fused together, giving them the appearance of a mermaid's tail. It is commonly associated with abnormal kidney development, genital and rectal abnormalities. A handful of cases have been reported in other parts of the world, however, no cases have previously been reported in a Nigerian neonate. To the best of our knowledge, we believe that this is the first case reported from West Africa and in a triplet. Case presentation A 16-hour-old baby boy, the second of a set of Nigerian triplets, presented to our facility with fusion of the entire lower limbs, imperforate anus, indiscernible genital structures, single umbilical artery and a neural tube defect. His parents were from the Hausa ethnic group and not related. Conclusion Sirenomelia has not been previously described in a set of triplets, and it is hoped that this report from West Africa will give information about the non-racial predilection of this condition.

  6. [2+2] Photocycloaddition reaction dynamics of triplet pyrimidines.

    Science.gov (United States)

    Yang, Chunfan; Yu, Youqing; Liu, Kunhui; Song, Di; Wu, Lidan; Su, Hongmei

    2011-06-01

    Taking the 266 nm excited pyrimidine (uracil or thymine) with cyclopentene as model reaction systems, we have examined the photoproduct formation dynamics from the [2 + 2] photocycloaddition reactions of triplet pyrimidines in solution and provided mechanistic insights into this important DNA photodamage reaction. By combining two compliment methods of nanosecond time-resolved transient IR and UV-vis laser flash-photolysis spectroscopy, the photoproduct formation dynamics as well as the triplet quenching kinetics are measured. Characteristic IR absorption bands due to photoproduct formation have been observed and product quantum yields are determined to be ∼0.91% for uracil and ∼0.41% for thymine. Compared to the measured large quenching rate constants of triplet uracil (1.5 × 10(9) M(-1)s(-1)) or thymine (0.6 × 10(9) M(-1)s(-1)) by cyclopentene, the inefficiency in formation of photoproducts indicates competitive physical quenching processes may exist on the route leading to photoproducts, resulting in very small product yields eventually. Such an energy wasting process is found to be resulted from T(1)/S(0) surface crossings by the hybrid density functional calculations, which compliments the experiments and reveals the reaction mechanism. PMID:21557584

  7. Polaron pair mediated triplet generation in polymer/fullerene blends

    KAUST Repository

    Dimitrov, Stoichko D.

    2015-03-04

    Electron spin is a key consideration for the function of organic semiconductors in light-emitting diodes and solar cells, as well as spintronic applications relying on organic magnetoresistance. A mechanism for triplet excited state generation in such systems is by recombination of electron-hole pairs. However, the exact charge recombination mechanism, whether geminate or nongeminate and whether it involves spin-state mixing is not well understood. In this work, the dynamics of free charge separation competing with recombination to polymer triplet states is studied in two closely related polymer-fullerene blends with differing polymer fluorination and photovoltaic performance. Using time-resolved laser spectroscopic techniques and quantum chemical calculations, we show that lower charge separation in the fluorinated system is associated with the formation of bound electron-hole pairs, which undergo spin-state mixing on the nanosecond timescale and subsequent geminate recombination to triplet excitons. We find that these bound electron-hole pairs can be dissociated by electric fields.

  8. Spin and charge transport in hybrid triplet Josephson junctions

    International Nuclear Information System (INIS)

    We report a theoretical study on the spin and charge transport in hybrid triplet Josephson junctions, of which the triplet pair potentials could have both different orbital symmetries and spin states. Based on a lattice model and a Hamiltonian method, we find that the spin/charge supercurrent is proportional to sin2ψ with ψ being the macroscopic superconducting phase, coming from the second-order Josephson effect, when the orbital symmetries of pair potentials in the two triplet superconductors are orthogonal to each other. A dissipationless transverse spin current is also found flowing at the interface of the junction and its polarization points along the cross-product of two d vectors, which arises from the combined effect of the orthogonal orbital symmetries and misalignment of d vectors. In a special hybrid junction, where the zero-energy states are absent at the interface of the junction, there is no net spin supercurrent flowing through the junction although two d vectors can be perpendicular to each other, whereas a mode-resolved spin supercurrent is flowing in the system instead.

  9. Development of a Triplet-Triplet Absorption Ruler: DNA- and Chromatin-Mediated Drug Molecule Release from a Nanosurface.

    Science.gov (United States)

    Chakraborty, Sudeshna Das; Sau, Abhishek; Kuznetsov, Denis V; Banerjee, Amrita; Bardhan, Munmun; Bhattacharya, Maireyee; Dasgupta, Dipak; Basu, Samita; Senapati, Dulal

    2016-07-14

    Triplet-triplet (T-T) absorption spectroscopy has been used successfully as a molecular ruler to understand the actual release process of sanguinarine as a drug molecule from a gold nanoparticle surface in the presence of cell components, that is, DNA and chromatin. The obtained results have been verified by fluorescence and surface-enhanced Raman spectroscopy (SERS), and a plausible explanation has been put forward to describe the underestimation and overestimation of the percentage (%) of the release of drug molecules measured by fluorescence- and SERS-based techniques, respectively, over the highlighted T-T absorption spectroscopy. Because of the intrinsic nature of absorption, the reported T-T absorption spectroscopic assay overpowers fluorescence- and SERS-based assays, which are limited by the long-range interaction and nonlinear dependence of the concentration of analytes, respectively. PMID:27284775

  10. Triplet-Polaron-Interaction-Induced Upconversion from Triplet to Singlet: a Possible Way to Obtain Highly Efficient OLEDs.

    Science.gov (United States)

    Obolda, Ablikim; Peng, Qiming; He, Chuanyou; Zhang, Tian; Ren, Jiajun; Ma, Hongwei; Shuai, Zhigang; Li, Feng

    2016-06-01

    Two D-A-type molecules, 4-N-[4-(9-phenylcarbazole)]-3,5-bis(4-diphenylamine)phenyl-4H-1,2,4-triazole and 4,4'-(9-(4-(1-phenyl-1H-phenanthro[9,10-d]imidazol-2-yl)phenyl)-9H-carbazole-3,6-diyl) bis-(N,N-diphenylaniline), are designed and synthesized. Organic lightemitting diodes based on them exhibit deep-blue emission and the singlet formation ratios are higher than the simple spin-statistics of 25%. A triplet-polaroninteraction-induced upconversion from triplet to singlet through a one-electron transfer mechanism is proposed, and is proven by magnetocurrent measurement and quantum-chemistry computation. PMID:27028509

  11. Monochorionic triamniotic triplet pregnancy with a co-triplet fetus discordant for congenital cystic adenomatoid malformation of the lung

    Directory of Open Access Journals (Sweden)

    Ceylan Yavuz

    2005-04-01

    Full Text Available Abstract Background Spontaneous monochorionic triamniotic pregnancy is rare and is at increased risk for pregnancy complications. The presence of an anomalous fetus further complicates the management. Case presentation We present a case of monochorionic triamniotic triplet pregnancy diagnosed at 15 weeks of gestation with one fetus having developed a multicystic lung lesion, suggestive of congenital cystic adenomatoid malformation (CCAM. At 24 weeks, the largest cyst measured 10 mm in diameter. We managed the pregnancy conservatively and delivered three live male fetuses with birth weights 1560 g, 1580 g and 1590 g at 35 weeks of gestation. Two newborns were admitted to the neonatal intensive care unit with respiratory distress, the third one died due to sepsis 7 days postpartum. One of the newborns was discharged healthy at 24 days postpartum. The newborn with CCAM developed a pneumothorax on the right side, recovered after treatment, and was discharged after one month. Computerized tomography (CT of the infant at 3 months demonstrated two cystic lesions in the middle lobe of the right lung measuring 25 mm and 15 mm. A repeat CT of the infant at 6 months showed a 30 mm solitary cystic mass. Conclusion Monochorionic triamniotic triplet pregnancy with a co-triplet fetus discordant for CCAM, present rarely and can be managed conservatively. These findings may help in decision making and counselling of parents.

  12. Physical conditions in CaFe interstellar clouds

    OpenAIRE

    Gnacinski, P.; Krogulec, M.

    2007-01-01

    Interstellar clouds that exhibit strong Ca I and Fe I lines were called CaFe clouds. The ionisation equilibrium equations were used to model the column densities of Ca II, Ca I, K I, Na I, Fe I and Ti II in CaFe clouds. The chemical composition of CaFe clouds is that of the Solar System and no depletion of elements onto dust grains is seen. The CaFe clouds have high electron densities n=1 cm^-3 that leads to high column densities of neutral Ca and Fe.

  13. Competition between triplet, singlet, and FFLO states in organic superconductors (TMTSF)2X under magnetic field

    International Nuclear Information System (INIS)

    We study the competition between triplet f-wave, singlet d-wave, and the FFLO state in a model for (TMTSF)2X using random phase approximation. The result suggests the possibility of singlet →FFLO→triplet transition upon increasing the magnetic field. The singlet →FFLO→triplet transition can appear in a large parameter regime on the space of the magnetic field and the off-site repulsions which induce the coexistence with 2kF charge and 2kF spin fluctuations, although decreasing the off-site repulsions suppresses the spin triplet f-wave pairing. We also show that the triplet component mixing increases in the FFLO state with increasing the magnetic field, and the off-site repulsions increase the mixing rate. The results seem to suggest that the large triplet mixing results in an enhanced tendency toward the FFLO state over the usual pairing state.

  14. Angiotensin II type 1 receptors stimulate protein synthesis in human cardiac fibroblasts via a Ca2+-sensitive PKC-dependent tyrosine kinase pathway

    DEFF Research Database (Denmark)

    Hou, M; Pantev, E; Möller, S;

    2000-01-01

    ) was obtained at a concentration of 10 nM. There were no significant alterations of cell number or total protein content, suggesting that Ang II stimulated protein synthesis but did not induce hypertrophy. The accumulation of 3H-leucine was blocked by the AT1 receptor antagonist candesartan but not by...

  15. Conjoined twins in a monochorionic triplet pregnancy after in vitro fertilization: a case report

    OpenAIRE

    Marzieh Talebian; Fatemeh Rahimi-Sharbaf; Mahboobeh Shirazi; Batool Teimoori; Narges Izadi-mood; Soheila Sarmadi

    2015-01-01

    Background: Monozygotic monochorionic triplet pregnancy with conjoined twins is a very rare condition and is associated with many complications. Case: In this study, we describe a monochorionic–diamniotic triplet pregnancy after in vitro fertilization with an intracytoplasmic sperm injection. At a gestational age of 6 weeks and 4 days of pregnancy one gestational sac was observed, and at a gestational age of 12 weeks and 2 days, triplets with conjoined twins were diagnosed. After consultin...

  16. Chirality and spin transformation of triplet Cooper pairs upon interaction with singlet condensate

    OpenAIRE

    Moor, Andreas; Volkov, Anatoly F.; Efetov, Konstantin B.

    2015-01-01

    We show that the fully polarized triplet s-wave component is characterized not only by the spin direction, but also by chirality. Interaction of a polarized triplet component and a singlet one results in creation of triplet Cooper pairs with opposite spin direction or of different chiralities. Such spin transformation leads to interesting phenomena in multiterminal magnetic Josephson junctions. We calculate the dc Josephson current $I_{\\text{J}}$ in a multiterminal Josephson contact of the S$...

  17. Excited triplet states as photooxidants in surface waters

    Science.gov (United States)

    Canonica, S.

    2012-12-01

    The chromophoric components of dissolved organic matter (DOM) are generally the main absorbers of sunlight in surface waters and therefore a source of transient reactants under irradiation. Such short-lived species can be relevant for the fate of various classes of chemical contaminants in the aquatic environment. The present contribution focuses on the role of excited triplet states of chromophoric DOM, 3CDOM*, as transient photooxidants initiating the transformation and degradation of organic chemical contaminants. An early study [1] indicated that 3CDOM* may play a dominant role in the photo-induced transformation of electron-rich phenols, a conclusion which was later fortified by the results of transient absorption investigations using aromatic ketones as model photosensitizers [2] and by a recent careful analysis of the effect of oxygen concentration on transformation rates [3]. The variety of aquatic contaminants shown to be affected by triplet-induced oxidation has kept increasing, phenylurea herbicides [4], sulfonamide antibiotics [5] and some phytoestrogens [6] being prominent examples. Recent research has shown that the triplet-induced transformation of specific contaminants, especially aromatic nitrogen compounds, could be inhibited by the presence of DOM, very probably due to its antioxidant moieties [7]. While such moieties are not relevant for the quenching of 3CDOM*, they are expected to react with it in a similar way as the studied contaminants. Analogous reactions can be postulated to occur in liquid or solid phases of the atmospheric environment, as demonstrated in the case of HONO formation [8]. References 1. Canonica, S.; Jans, U.; Stemmler, K.; Hoigné, J. Transformation kinetics of phenols in water: Photosensitization by dissolved natural organic material and aromatic ketones. Environ. Sci. Technol. 1995, 29 (7), 1822-1831. 2. Canonica, S.; Hellrung, B.; Wirz, J. Oxidation of phenols by triplet aromatic ketones in aqueous solution. J. Phys

  18. Semantic similarity: normative ratings for 185 Spanish noun triplets.

    Science.gov (United States)

    Moldovan, Cornelia D; Ferré, Pilar; Demestre, Josep; Sánchez-Casas, Rosa

    2015-09-01

    The present study introduces the first Spanish database with normative ratings of semantic similarity for 185 word triplets. Each word triplet is constituted by a target word (e.g., guisante [pea]) and two semantically related and nonassociatively related words: a word highly related in meaning to the target (e.g., judía [bean]), and a word less related in meaning to the target (e.g., patata [potato]). The degree of meaning similarity was assessed by 332 participants by using a semantic similarity rating task on a 9-point scale. Pairs having a value of semantic similarity ranging from 5 to 9 were classified as being more semantically related, whereas those with values ranging from 2 to 4.99 were considered as being less semantically related. The relative distance between the two pairs for the same target ranged from 0.48 to 5.07 points. Mean comparisons revealed that participants rated the more similar words as being significantly more similar in meaning to the target word than were the less similar words. In addition to the semantic similarity norms, values of concreteness and familiarity of each word in a triplet are provided. The present database can be a very useful tool for scientists interested in designing experiments to examine the role of semantics in language processing. Since the variable of semantic similarity includes a wide range of values, it can be used as either a continuous or a dichotomous variable. The full database is available in the supplementary materials. PMID:24984982

  19. Line-absorption of He-like triplet lines by Li-like ions: Caveats of using line ratios of triplets for plasma diagnostics

    CERN Document Server

    Mehdipour, M; Raassen, A J J

    2015-01-01

    He-like ions produce distinctive series of triplet lines under various astrophysical conditions. However, this emission can be affected by line-absorption from Li-like ions in the same medium. We investigate this absorption of He-like triplets and present the implications for diagnostics of plasmas in photoionisation equilibrium using the line ratios of the triplets. Our computations are carried out for the O VI and Fe XXIV absorption of the O VII and Fe XXV triplet emission lines, respectively. The fluorescent emission by the Li-like ions and continuum absorption of the He-like ion triplet lines are also investigated. We determine the absorption of the triplet lines as a function of Li-like ion column density and velocity dispersion of the emitting/absorbing medium. We find O VI line-absorption can significantly alter the O VII triplet line ratios in optically-thin plasmas, by primarily absorbing the intercombination lines and to lesser extent the forbidden line. Due to intrinsic line-absorption by O VI insi...

  20. H2 triplet states contribution to low-energy dissociative recombination of H2+

    International Nuclear Information System (INIS)

    Motivated by the observation of the predissociation of H2 triplet states in low vibrational levels, we evaluate the contribution of triplet dissociative states to the low-energy dissociative recombination of H2+ in vibrational levels where v = 0, 1. The triplet states contribute mainly via radial couplings between monoexcited Rydberg configurations without curve crossings. The total contribution of the six triplet states leading to dissociation in H(n = 1) + H(n = 2) is found to be smaller by at least one order of magnitude than the contribution of the lowest doubly excited singlet state, (2pσu)21 Σg+

  1. Competition between triplet, singlet and FFLO states in organic superconductors (TMTSF)2X under magnetic field

    International Nuclear Information System (INIS)

    We study the competition between triplet f-wave, singlet d-wave, and the FFLO state in a model for (TMTSF)2X using random phase approximation. The result suggests the possibility of the singlet→FFLO→triplet transition upon increasing the magnetic field. We also show that the triplet component mixing increases in the FFLO state with increasing the magnetic field, and the off-site repulsions increase the mixing rate. The results seem to suggest that the large triplet mixing results in an enhanced tendency toward the FFLO state over the usual pairing state.

  2. ISORROPIA II: a computationally efficient thermodynamic equilibrium model for K+─Ca²+─Mg²+─NH4+─Na+─SO4²-─NO3-─Cl-─H2O aerosols

    Directory of Open Access Journals (Sweden)

    C. Fountoukis

    2007-09-01

    Full Text Available This study presents ISORROPIA II, a thermodynamic equilibrium model for the K+–Ca2+–Mg2+–NH4+–Na+–SO42−–NO3−–Cl−–H2O aerosol system. A comprehensive evaluation of its performance is conducted against water uptake measurements for laboratory aerosol and predictions of the SCAPE2 thermodynamic module over a wide range of atmospherically relevant conditions. The two models agree well, to within 13% for aerosol water content and total PM mass, 16% for aerosol nitrate and 6% for aerosol chloride and ammonium. Largest discrepancies were found under conditions of low RH, primarily from differences in the treatment of water uptake and solid state composition. In terms of computational speed, ISORROPIA II was more than an order of magnitude faster than SCAPE2, with robust and rapid convergence under all conditions. The addition of crustal species does not slow down the thermodynamic calculations (compared to the older ISORROPIA code because of optimizations in the activity coefficient calculation algorithm. Based on its computational rigor and performance, ISORROPIA II appears to be a highly attractive alternative for use in large scale air quality and atmospheric transport models.

  3. THE LICK/SDSS LIBRARY. II. [Ca/Fe] AND [Mg/Fe] IN F, G, AND K STARS FROM SDSS-DR7

    International Nuclear Information System (INIS)

    We analyzed the spectra of 17,600 F, G, and K stars extracted from the seventh Sloan Digital Sky Survey Data Release (SDSS-DR7) database in order to derive ([α/Fe]), [Ca/Fe], and [Mg/Fe] ratios. Particular attention has been devoted to estimating homogeneous and self-consistent atmospheric parameter values, Teff, log g, and [Fe/H], by comparing synthetic and observational Lick/SDSS indices. We present results for the sub-sample of more than 4000 spectra whose overall quality allowed us to derive fairly accurate stellar atmospheric parameter values and, therefore, reliable abundance ratios. A Monte Carlo approach was adopted to evaluate both the errors in the observational Lick/SDSS indices and in the derived parameter estimates. The analysis of the trends of [Ca/Fe] and [Mg/Fe] versus [Fe/H] pointed out that (1) the [Ca/Fe] and [Mg/Fe] ratios increase with decreasing [Fe/H] with different slopes reaching maximum average levels of +0.25 and +0.40 dex at [Fe/H] ≅ -1.75, respectively; (2) our sample contains, at a given [Fe/H], stars characterized by significantly different amounts of α-enhancement, thus belonging to different Galactic populations; and (3) the analyzed sample shows a predominance of thick disk stars for [Fe/H] > - 0.5 and the presence of stars belonging to the high-αhalo population for -2.0 < [Fe/H] <-0.5.

  4. I. Synthesis, modification and characterization of BiSr-CaCuOx single crystal superconductors. II. Synthesis and characterization of one dimensional rutheniumtetrammine-pyrazine polymers

    International Nuclear Information System (INIS)

    Through metal substitution, the author has selectively introduced Pb, La, Y, and Fe into Bi-O, Sr-O, Ca and Cu-O layers of Bi2Sr2CaCu2O8+δ (referred to as Bi-2212) single crystal superconductors. Crystal samples of these modified systems were grown using melt flux method at high temperature, followed by slow cooling. The synthesis was investigated at different equilibrium temperatures, cooling rates and at an atmosphere with different percentage of O2 in the O2/N2 mixture. The composition of the crystals was determined by electron microprobe and elemental analyses. These analyses indicated that Pb primarily substituted for Bi, La for Sr and Y for Ca. X-ray diffraction gave the orthorhombic symmetry for the meal substituted and pure Bi-2212 samples. Magnetization hysteresis measurements were used to determine critical current density (Jc) in these materials. For Pb doped samples, Jc increased by about one order of magnitude. Analysis of magnetic relaxation data indicates that the magnitude of Jc is correlated with pinning well depth (U0). The quality of the crystals, in terms of transition width and Meissner fraction, was improved by annealing in an O2/Ar atmosphere. Annealing exhibited improved transition temperature (Tc) and higher Jc. Lastly, the relationship between superconductivity and oxygen stoichiometry was investigated systematically for the Bi-2212 single crystal samples. The results show that superconductivity is closely related to oxygen content of these materials. One-dimensional tetrammine-ruthenium polymers bridged by pyrazine were synthesized and characterized. As the chain length of the polymers increased, the metal to ligand charge transfer (MLCT) transition was found to red shift. Infrared (IR) spectroscopy was used to determine the chain length. After doping with Br2, the conductivity of the polymers increased by three orders of magnitude

  5. Capturing triplet emission in white organic light emitting devices

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Jai [Faculty of EHSE, School of Engineering and IT, B-purple-12, Charles Darwin University, Darwin, NT 0909 (Australia)

    2011-08-15

    The state-of-the art in the white organic light emitting devices (WOLEDs) is reviewed for further developments with a view to enhance the capture of triplet emission. In particular, applying the new exciton-spin-orbit-photon interaction operator as a perturbation, rates of spontaneous emission are calculated in a few phosphorescent materials and compared with experimental results. For iridium based phosphorescent materials the rates agree quite well with the experimental results. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Quark fragmentation into spin-triplet $S$-wave quarkonium

    CERN Document Server

    Bodwin, Geoffrey T; Kim, U-Rae; Lee, Jungil

    2014-01-01

    We compute fragmentation functions for a quark to fragment to a quarkonium through an $S$-wave spin-triplet heavy quark-antiquark pair. We consider both color-singlet and color-octet heavy quark-antiquark ($Q\\bar Q$) pairs. We give results for the case in which the fragmenting quark and the quark that is a constituent of the quarkonium have different flavors and for the case in which these quarks have the same flavors. Our results for the sum over all spin polarizations of the $Q\\bar Q$ pairs confirm previous results. Our results for longitudinally polarized $Q\\bar Q$ pairs are new.

  7. Testing Higgs Triplet Model and Neutrino Mass Patterns

    CERN Document Server

    Chun, E J; Park, S C; Chun, Eung Jin; Lee, Kang Young; Park, Seong Chan

    2003-01-01

    The observed neutrino oscillation data might be explained by new physics at a TeV scale, which is testable in the future experiments. Among various possibilities, the low-energy Higgs triplet model is a prime candidate of such new physics since it predicts clean signatures of lepton flavor violating processes directly related to the neutrino masses and mixing. It is discussed how various neutrino mass patterns can be discriminated by examining the lepton flavor violating decays of charged leptons as well as the collider signatures of a doubly charged Higgs boson in the model.

  8. Predissociation and autoionization of triplet Rydberg states in molecular hydrogen

    OpenAIRE

    Dinu, L.; Picard, Y. J.; Van Der Zande, W. J.

    2004-01-01

    We present single-photon spectroscopy in molecular hydrogen starting from the metastable c(3)Pi(u)(-) state to a number of triplet nd-Rydberg states (v=0-4, n=12-20). Using fast beam spectroscopy both the autoionization channel and the predissociation channel are quantified, field free, as well as with small electric fields. Coupling with the i(3)Pi(g) state is assumed to be responsible for field-free predissociation of the v=0 Rydberg levels. The stronger observed predissociation channel of ...

  9. Triplet supercurrent in ferromagnetic Josephson junctions by spin injection

    Science.gov (United States)

    Mal'shukov, A. G.; Brataas, Arne

    2012-09-01

    We show that injecting nonequilibrium spins into the superconducting leads strongly enhances the stationary Josephson current through a superconductor-ferromagnet-superconductor junction. The resulting long-range supercurrent through a ferromagnet is carried by triplet Cooper pairs that are formed in s-wave superconductors by the combined effects of spin injection and exchange interaction. We quantify the exchange interaction in terms of Landau Fermi-liquid factors. The magnitude and direction of the long-range Josephson current can be manipulated by varying the angles of the injected polarizations with respect to the magnetization in the ferromagnet.

  10. Status of the LHC inner triplet quadrupole program at Fermilab

    CERN Document Server

    Andreev, N; Bauer, P; Bossert, R; Brandt, J; Carson, J; Caspi, S; Chichili, D R; Chiesa, L; Darve, C; Di Marco, J; Fehér, S; Ghosh, A; Glass, H; Huang, Y; Kerby, J S; Lamm, M J; Markarov, A A; McInturff, A D; Nicol, T H; Nobrega, A; Novitski, I; Ogitsu, T; Orris, D; Ozelis, J P; Page, T; Peterson, T; Rabehl, Roger Jon; Robotham, W; Sabbi, G L; Scanlan, R M; Schlabach, P; Sylvester, C D; Strait, J B; Tartaglia, M; Tompkins, J C; Velev, G V; Yadav, S; Zlobin, A V

    2001-01-01

    Fermilab, in collaboration with LBNL and BNL, is developing a quadrupole for installation in the interaction region inner triplets of the LHC. This magnet is required to have an operating gradient of 215 T/m across a 70 mm coil bore, and operates in superfluid helium at 1.9 K. A 2 m magnet program addressing mechanical, magnetic, quench protection, and thermal issues associated with the design was completed earlier this year, and production of the first full length, cryostatted prototype magnet is underway. This paper summarizes the conclusions of the 2 m program, and the design and status of the first full-length prototype magnet. (11 refs).

  11. Clarifying the mechanism of triplet-triplet annihilation in phosphorescent organic host-guest systems: A combined experimental and simulation study

    Science.gov (United States)

    Zhang, L.; van Eersel, H.; Bobbert, P. A.; Coehoorn, R.

    2016-05-01

    At high brightness, triplet-triplet annihilation (TTA) reduces the efficiency of organic light-emitting diodes. Triplet diffusion may considerably enhance this effect, which is otherwise limited by the rate of long-range interactions. Although its role can be clarified by studying the emissive dye concentration dependence of the TTA loss, we demonstrate here the practical applicability of a more direct method, requiring a study for only a single dye concentration. The method uses transient photoluminescence yield measurements, for a wide initial excitation density range. The analysis is applied to an iridium complex and is supported by the results of kinetic Monte Carlo simulations.

  12. Triplet Extended MSSM: Fine Tuning vs Perturbativity and Experiment

    CERN Document Server

    Bandyopadhyay, Priyotosh; Huitu, Katri; Keçeli, Aslı Sabancı

    2014-01-01

    In this study we investigate the phenomenological viability of the $Y=0$ Triplet Extended Supersymmetric Standard Model (TESSM) by comparing its predictions with the current Higgs data from ATLAS, CMS, and Tevatron, as well as the measured value of the $B_s\\to X_s \\gamma$ branching ratio. We scan numerically the parameter space for data points generating the measured particle mass spectrum and also satisfying current direct search constraints on new particles. We require all the couplings to be perturbative up to the scale $\\Lambda_{\\rm UV}=10^4$ TeV, by running them with newly calculated two loop beta functions, and find that TESSM retains perturbativity as long as $\\lambda$, the triplet coupling to the two Higgs doublets, is smaller than 1.34 in absolute value. For $|\\lambda|\\gtrsim 0.8$ we show that the fine-tuning associated to each viable data point can be greatly reduced as compared to values attainable in MSSM. Finally, we perform a fit by taking into account 58 Higgs physics observables along with $\\m...

  13. Efficient Design of Triplet Based Spike-Timing Dependent Plasticity

    CERN Document Server

    Azghadi, Mostafa Rahimi; Iannella, Nicolangelo; Abbott, Derek

    2012-01-01

    Spike-Timing Dependent Plasticity (STDP) is believed to play an important role in learning and the formation of computational function in the brain. The classical model of STDP which considers the timing between pairs of pre-synaptic and post-synaptic spikes (p-STDP) is incapable of reproducing synaptic weight changes similar to those seen in biological experiments which investigate the effect of either higher order spike trains (e.g. triplet and quadruplet of spikes), or, simultaneous effect of the rate and timing of spike pairs on synaptic plasticity. In this paper, we firstly investigate synaptic weight changes using a p-STDP circuit and show how it fails to reproduce the mentioned complex biological experiments. We then present a new STDP VLSI circuit which acts based on the timing among triplets of spikes (t-STDP) that is able to reproduce all the mentioned experimental results. We believe that our new STDP VLSI circuit improves upon previous circuits, whose learning capacity exceeds current designs due ...

  14. Mode of conception of triplets and high order multiple pregnancies.

    LENUS (Irish Health Repository)

    Basit, I

    2012-03-01

    A retrospective audit was performed of all high order multiple pregnancies (HOMPs) delivered in three maternity hospitals in Dublin between 1999 and 2008. The mode of conception for each pregnancy was established with a view to determining means of reducing their incidence. A total of 101 HOMPs occurred, 93 triplet, 7 quadruplet and 1 quintuplet. Information regarding the mode of conception was available for 78 (81%) pregnancies. Twenty eight (27.7%) were spontaneous, 34 (33.7%) followedlVF\\/ICSI\\/FET treatment (in-vitro fertilisation, intracytoplasmic sperm injection, frozen embryo transfer), 16 (15.8%) resulted from Clomiphene Citrate treatment and 6 (6%) followed ovulation induction with gonadotrophins. Triplet and HOMPs are a major cause of maternal, feta land neonatal morbidity. Many are iatrogenic, arising from fertility treatments including Clomiphene. Reducing the numbers of embryos transferred will address IVF\\/ICSI\\/FET-related multiple pregnancy rates and this is currently happening in Ireland. Clomiphene and gonadotrophins should only be prescribed when appropriate resources are available to monitor patients adequately.

  15. Optical identification of the long-wavelength (700-1700 nm) electronic excitations of the native reaction centre, Mn4CaO5 cluster and cytochromes of photosystem II in plants and cyanobacteria.

    Science.gov (United States)

    Morton, Jennifer; Akita, Fusamichi; Nakajima, Yoshiki; Shen, Jian-Ren; Krausz, Elmars

    2015-02-01

    Visible/UV absorption in PS II core complexes is dominated by the chl-a absorptions, which extend to ~700 nm. A broad 700-730 nm PS II core complex absorption in spinach has been assigned to a charge transfer excitation between ChlD1 and ChlD2. Emission from this state, which peaks at 780 nm, has been seen for both plant and cyanobacterial samples. We show that Thermosynechococcus vulcanus PS II core complexes have parallel absorbance in the 700-730 nm region and similar photochemical behaviour to that seen in spinach. This establishes the low energy charge transfer state as intrinsic to the native PS II reaction centre. High-sensitivity MCD measurements made in the 700-1700 nm region reveal additional electronic excitations at ~770 nm and ~1550 nm. The temperature and field dependence of MCD spectra establish that the system peaking near 1550 nm is a heme-to-Fe(III) charge transfer excitation. These transitions have not previously been observed for cyt b559 or cyt c550. The distinctive characteristics of the MCD signals seen at 770 nm allow us to assign absorption in this region to a dz(2)→d(x2-y2) transition of Mn(III) in the Ca-Mn4O5 cluster of the oxygen evolving centre. Current measurements were performed in the S1 state. Detailed analyses of this spectral region, especially in higher S states, promise to provide a new window on models of water oxidation. PMID:25445315

  16. Effect of hydrogen on the behavior of metals II - Hydrogen embrittlement of titanium alloy TV13CA - effect of oxygen - comparison with non-alloyed titanium

    International Nuclear Information System (INIS)

    The effect of oxygen on the hydrogen embrittlement of non-alloyed titanium and the metastable β titanium alloy, TV13 CA, was studied during dynamic mechanical tests, the concentrations considered varying from 1000 to 5000 ppm (oxygen) and from 0 to 5000 ppm (hydrogen) respectively. TV13 CA alloy has a very high solubility for hydrogen. The establishment of a temperature range and a rate of deformation region in which the embrittlement of the alloy is maximum leads to the conclusion that an embrittlement mechanism occurs involving the dragging and accumulation of hydrogen by dislocations. This is the case for all annealings effected in the medium temperature range, which, by favoring the re-establishment of the stable two-phase α + β state of the alloy, produce hardening. The same is true for oxygen which, in addition to hardening the alloy by the solid solution effect, tends to increase its instability and, in consequence, favors the decomposition of the β phase. Nevertheless oxygen concentrations of up to 1500 ppm contribute to increasing the mechanical resistance without catastrophically reducing the deformation capacity. In the case of non-alloyed titanium, the hardening effect also leads to an increase in E0.2pc and R, and to a reduction in the deformation capacity. Nevertheless, hydrogen is only very slightly soluble at room temperature and a distribution of the hydride phase linked to the thermal history of the sample predominates. Thus a fine acicular structure obtained from the β phase by quenching, enables an alloy having a good mechanical resistance to be conserved even when large quantities of hydrogen are present; the deformation capacity remains small. On the other hand, when the hydride phase separates the metallic phase into large grains, a very small elongation leads to a breakdown in mechanical resistance. (author)

  17. A top condensate model with a Higgs doublet and a Higgs triplet

    CERN Document Server

    Jora, Renata; Schechter, Joseph

    2013-01-01

    We reconsider top condensate models from the perspective that not only two quark composite fields can form but also four quark ones. We obtain a model which contains a Higgs doublet and a Higgs triplet, where one of the neutral components of the Higgs triplet identifies with the Higgs boson found at the LHC. We discuss some of the phenomenological consequences.

  18. Quenching of the triplet state of benzophenone by lanthanide 1,3-diketonate chelates in solutions

    International Nuclear Information System (INIS)

    The phosphorescence of benzophenone in benzene and acetonitrile was quenched by several lanthanide (Sm, Eu, Gd, Tb and Dy) acetylacetonate chelates. The results of Stern-Volmer analysis including the quenching of benzophenone triplet and sensitization of lanthanide emission indicate that the quenching process occurs by the energy transfer mechanism via the excited triplet state of the ligand. (Author)

  19. QUANTUM CHEMICAL STUDY GEOMETRICAL AND ELECTRONIC STRUCTURES AMINONITRENE IN SINGLET AND TRIPLET STATES

    OpenAIRE

    Ostapenko, Gennady; Troshina, Marina

    2014-01-01

    Ab initio methods MO LCAO SCF using wide basis sets (6-311G( 3d, 2p ), cc-pVTz) calculated geometric and electronic parameters of the singlet and triplet forms aminonitrene, force field parameters and values ​​of the oscillation frequency, as well as the thermodynamic parameters obtained stability of the singlet and triplet forms aminonitrene.

  20. Desorptions- und Reaktionskinetik der Erdalkalien Calcium und Strontium mit Chlor an Wolfram. Part II: Kinetics of the Elementary Steps of the Surface Reaction M + Cl MCl (M = Ca, Sr)

    Science.gov (United States)

    Biedermann, B.; Wassmuth, H. W.

    Mit Hilfe gepulster Atom-bzw. Molekularstrahlen wurde die Desorptionskinetik von Strontium, Calcium und Chlor sowie die Desorptionskinetik der sich auf einer heißen Wolframoberfläche bildenden SrCl-und CaCl- Moleküle untersucht. Als Aktivierungsenergien zur Desorption erhielten wir: = (3,76 +/- 0,05) eV, =(3,32 +/- 0,07) eV, =(4,16 +/- 0,05) eV sowie =(4,2 +/- 0,3) eV und =(3,9 +/- 0, 3)eV.In Kombination mit den im stationären Zustand erhaltenen Ergebnissen aus Teil I [1] läßt sich damit ein Einblick in die Kinetik der Reaktion M + Cl = MCl auf der wolframoberfläche gewinnen und die Temperaturabhängigkeit der Ratenkonstanten der Dissoziation und der Rekombination bestimmen. FuUr die Dissoziationsenergie DSMCl von SrCl bzw. CaCl an der Wolfram-Oberfläche erhielten wir (0,5 +/- 0,5) eV bzw. (0,3 +/- 0,5) eV; die MCl-Moleküle sind an der Oberfläche also praktisch nur durch die Aktivierungsschwelle zur Dissoziation SMCl stabilisiert, die wir für SrCl zu (2,8 +/- 0,5) eV und für CaCl zu (2,3 +/- 0,5) eV bestimmten.Translated AbstractDesorption- and Reactionkinetics of the Alkaline Earth Elements Calcium and Strontium with Chlorine on a Tungsten Surface - Part II: Kinetics of the Elementary Steps of the Surface Reaction M + Cl MCl (M = Ca, Sr)Utilizing pulsed molecular-beam-technique the kinetics of desorption of Strontium, Calcium, and Chlorine as well as that of the molecules SrCl and CaCl, which are formed at the hot tungsten surface, was investigated. Thereby, the following values were obtained for the activation energies of desorption: = (3.76 +/- 0.05) eV, = (3.32 +/- 0.07) eV, = (4.16 +/- 0.05) eV, = (4.2 +/- 0.3) eV and = (3.9 +/- 0.3) eV.Combining these results with the steady-state-results from part I [1] the temperature dependency of the rate constants of dissociation and recombination of MCl-molecules at the tungsten surface could be determined. The values obtained for the dissociation energies D of SrCl and CaCl on tungsten are (0.5 +/- 0.5) e

  1. Observation of Two Triplet-Pair Intermediates in Singlet Exciton Fission.

    Science.gov (United States)

    Pensack, Ryan D; Ostroumov, Evgeny E; Tilley, Andrew J; Mazza, Samuel; Grieco, Christopher; Thorley, Karl J; Asbury, John B; Seferos, Dwight S; Anthony, John E; Scholes, Gregory D

    2016-07-01

    Singlet fission is an excitation multiplication process in molecular systems that can circumvent energy losses and significantly boost solar cell efficiencies; however, the nature of a critical intermediate that enables singlet fission and details of its evolution into multiple product excitations remain obscure. We resolve the initial sequence of events comprising the fission of a singlet exciton in solids of pentacene derivatives using femtosecond transient absorption spectroscopy. We propose a three-step model of singlet fission that includes two triplet-pair intermediates and show how transient spectroscopy can distinguish initially interacting triplet pairs from those that are spatially separated and noninteracting. We find that the interconversion of these two triplet-pair intermediates is limited by the rate of triplet transfer. These results clearly highlight the classical kinetic model of singlet fission and expose subtle details that promise to aid in resolving problems associated with triplet extraction. PMID:27281713

  2. Legitional behavior of 5,5-diethylbarbituric acid sodium salt (HL) towards Mg, Ca, Sr, Ba(II), spectral, thermal and biological studies

    Science.gov (United States)

    Refat, Moamen S.; El-Metwaly, Nashwa M.

    2011-03-01

    A new series of sodium barbital complexes with Alkaline earth metals (Mg2+, Ca2+, Sr2+ and Ba2+ ions) was prepared. The molecular formulas for the isolated complexes were suggested basically on the elemental analysis data. The binuclear central were proposed for all investigated complexes. The geometry suggested based on knowing the coordination sits for each complex was built on concerning with the shift observed in IR spectra surround the coordinating groups. The shifts in charge transfer bands appeared in the electronic spectra of the complexes supports the coordination process. The presence of solvent molecules coordinately attached with central metal atoms as well as the conjugated anions was supported based on thermogravimetric analysis. The kinetic parameters were calculated for each complex. The theoretical calculations for the molecular modeling structures reflect an insight about their stability in comparing with the free ligand. The XRD studies were performed and concluding the nanocrystalline feature for all complexes. The biochemical effect of all investigated compounds was performed towards Gram-negative and Gram-positive bacteria as well as their degradation effect on calf Thymus DNA. The biological performance is the major goal in this study especially with such essential metal ions.

  3. Can the 750-GeV diphoton resonance be the singlet Higgs boson of custodial Higgs triplet model?

    Science.gov (United States)

    Chiang, Cheng-Wei; Kuo, An-Li

    2016-09-01

    The observation of diphoton excess around the mass of 750 GeV in LHC Run-II motivates us to consider whether the singlet Higgs boson in the custodial Higgs triplet model can serve as a good candidate because an earlier study of comprehensive parameter scan shows that it can have the right mass in the viable mass spectra. By assuming the singlet Higgs mass at 750 GeV, its total width less than 50 GeV and imposing constraints from the LHC 8-TeV data, we identify an approximately linear region on the (vΔ , α) plane along which the exotic Higgs boson masses satisfy a specific hierarchy and have lower possible spectra, where vΔ denotes the triplet vacuum expectation value and α is the mixing angle between the singlet Higgs boson and the standard model-like Higgs boson. Although the diphoton decay rate can be enhanced by charged Higgs bosons running in the loop in this region, it is mostly orders of magnitude smaller than that required for the observed production rate, except for the small vΔ region when the diphoton fusion production mechanism becomes dominant. Nonetheless, this part of parameter space suffers from the problems of breakdown of perturbativity and large uncertainties in the photon parton distribution function of proton.

  4. 130 GeV gamma ray line and enhanced Higgs di-photon rate from Triplet-Singlet extended MSSM

    CERN Document Server

    Basak, Tanushree

    2013-01-01

    We propose an economic extension of minimal supersymmetric standard model with a SU(2) singlet and Y=0 triplet, which can explain (i) the 125 GeV Higgs boson without fine tuning, (ii) the 130 GeV $\\gamma$-ray line seen at Fermi-LAT, (as well as a second photon line at 114 GeV)(iii) an enhanced Higgs di-photon decay rate seen by ATLAS, while being consistent with dark matter relic density and recent XENON 100 exclusion limits on spin-independent direct detection cross-section. We obtain the required cross-section of $10^{-27}cm^3s^{-1}$ for the 130 GeV $\\gamma$-ray flux through the resonant annihilation of dark matter via pseudoscalar triplet Higgs of mass $\\sim$260 GeV. The dark matter is predominantly bino-higgsino which has large couplings with photons (through higgsino) and gives correct relic density (through bino). We get the enhanced Higgs diphoton decay rate, $R_{\\gamma \\gamma}\\simeq 1.24$ dominantly contributed by the light chargino-loops, which can account for the reported excess seen in the $h\\right...

  5. Observation of rogue wave triplets in water waves

    Energy Technology Data Exchange (ETDEWEB)

    Chabchoub, A., E-mail: achabchoub@swin.edu.au [Centre for Ocean Engineering Science and Technology, Swinburne University of Technology, Hawthorn, Victoria 3122 (Australia); Department of Mechanical Engineering, Imperial College London, London SW7 2AZ (United Kingdom); Akhmediev, N. [Optical Sciences Group, Research School of Physics and Engineering, The Australian National University, Canberra, ACT 0200 (Australia)

    2013-11-15

    Doubly-localised breather solutions of the nonlinear Schrödinger equation (NLS) are considered to be appropriate models to describe rogue waves in water waves as well as in other nonlinear dispersive media such as fibre optics. Within the hierarchy of this type of formations, the Peregrine breather (PB) is the lowest-order rational solution. Higher-order solutions of this kind may be understood as a nonlinear superposition of fundamental Peregrine solutions. These superpositions are nontrivial and admit only a fixed well prescribed number of elementary breathers in each higher-order solution. Here, we report first observation of second-order solution which in reality is a triplet of rogue waves.

  6. Mother-daughter in vitro fertilization triplet surrogate pregnancy.

    Science.gov (United States)

    Michelow, M C; Bernstein, J; Jacobson, M J; McLoughlin, J L; Rubenstein, D; Hacking, A I; Preddy, S; Van der Wat, I J

    1988-02-01

    A successful triplet pregnancy has been established in a surrogate gestational mother following the transfer of five embryos fertilized in vitro. The oocytes were donated by her biological daughter, and the sperm obtained from the daughter's husband. The daughter's infertility followed a total abdominal hysterectomy performed for a postpartum hemorrhage as a result of a placenta accreta. Synchronization of both their menstrual cycles was obtained using oral contraceptive suppression for 2 months, followed by stimulation of both the surrogate gestational mother and her daughter such that embryo transfer would occur at least 48 hr after the surrogate gestational mother's own ovulation. This case raises a number of medical, social, psychological, and ethical issues. PMID:3367072

  7. Peripartum cardiomyopathy: a case of patient with triplet pregnancy.

    Science.gov (United States)

    Kotlica, B Kastratović; Cetković, A; Plesinac, S; Macut, D; Asanin, M

    2016-01-01

    Peripartum cardiomyopathy (PPCM) is a rare but potentially devastating complication of pregnancy associated with heart failure due to left ventricular systolic dysfunction occurring within the last month of pregnancy and five month postpartum with no obvious other cause of heart failure and no pre-existing heart disease. In the present case report the authors present a woman who developed PPCM on the day after she delivered by cesarean section in 35th weeks of gestation of triplet pregnancy conceived after ovarian stimulation and insemination. A treatment with diuretics, ACE inhibitors, antiarrhythmics, low weight heparin, antibiotics and bromocriptine was applied and resulted in complete recovery. In conclusion, timely detection and initiation of treatment are important factors for complete recovery of patients with PPCM. PMID:27132428

  8. Discovery of a tidal dwarf galaxy in the Leo Triplet

    International Nuclear Information System (INIS)

    We report the discovery of a dwarf galaxy in the Leo Triplet. Analysis of the neutral hydrogen distribution shows that it rotates independently of the tidal tail of NGC 3628, with a radial velocity gradient of 35-40 km s–1 over approximately 13 kpc. The galaxy has an extremely high neutral gas content, accounting for a large amount of its total dynamic mass and suggesting a low amount of dark matter. It is located at the tip of the gaseous tail, which strongly suggests a tidal origin. If this is the case, it would be one of the most confident and nearest (to the Milky Way) detections of a tidal dwarf galaxy and, at the same time, the object most detached from its parent galaxy (≈140 kpc) of this type.

  9. Model for Triplet State Engineering in Organic Light Emitting Diodes

    CERN Document Server

    Prodhan, Suryoday; Ramasesha, S

    2014-01-01

    Engineering the position of the lowest triplet state (T1) relative to the first excited singlet state (S1) is of great importance in improving the efficiencies of organic light emitting diodes and organic photovoltaic cells. We have carried out model exact calculations of substituted polyene chains to understand the factors that affect the energy gap between S1 and T1. The factors studied are backbone dimerisation, different donor-acceptor substitutions and twisted geometry. The largest system studied is an eighteen carbon polyene which spans a Hilbert space of about 991 million. We show that for reverse intersystem crossing (RISC) process, the best system involves substituting all carbon sites on one half of the polyene with donors and the other half with acceptors.

  10. Spin-triplet supercurrent through inhomogeneous ferromagnetic trilayers

    Science.gov (United States)

    Alidoust, Mohammad; Linder, Jacob

    2010-12-01

    Motivated by a recent experiment [J. W. A. Robinson, J. D. S. Witt, and M. G. Blamire, Science 329, 5987 (2010)10.1126/science.1189246], we report here the possibility of establishing a long-range spin-triplet supercurrent through an inhomogeneous ferromagnetic region consisting of a Ho∣Co∣Ho trilayer sandwiched between conventional s -wave superconducting leads. We utilize a full numerical solution in the diffusive regime of transport and study the behavior of the supercurrent for various experimentally realistic configurations of the ferromagnetic trilayer. We obtain qualitatively very good agreement with experimental data regarding the behavior of the supercurrent as a function of the width of the Co layer, LCo . Moreover, we find a synthesis of 0-π oscillations with superimposed rapid oscillations when varying the width of the Ho layers symmetrically, which pertain specifically to the spiral magnetization texture in Ho. Although we are not able to reproduce the anomalous sharp peaks in the supercurrent vs Ho-layer thickness observed experimentally in this regime, the results obtained are quite sensitive to the exact magnetization profile in the Ho layers. This might be the reason for the discrepancy between our results and the experimental reported data for this particular aspect. We also investigate the supercurrent in a system where the intrinsically inhomogeneous Ho ferromagnets are replaced with domain-wall ferromagnets and find similar behavior as in the Ho∣Co∣Ho case. Furthermore, we propose magnetic Josephson junctions including only a domain-wall ferromagnet and a homogeneous ferromagnetic layer. The hybrid structure not only is simple regarding the magnetization profile but also offers a tunable long-range spin-triplet supercurrent. Finally, we discuss some experimental aspects of our findings.

  11. Comment on "Triplet-to-Singlet Exciton Formation in poly(p-phenylene-vinylene) Light-Emitting Diodes"

    OpenAIRE

    Mazumdar, S.; Das, Mousumi; Ramasesha, S.

    2003-01-01

    The low-lying singlet and triplet spectrum in conjugated polymers clearly show that the mechanism proposed by Lin et al. to explain their electric field dependence of singlet to triplet yield ratios is wrong. This comment, from theoretical spectrum obtained for long polyenes, shows that the phonon bottleneck proposed by Lin et al. for triplets in polyenes cannot exist.

  12. LHC diphoton and Z+photon Higgs signals in the Higgs triplet model with Y = 0

    International Nuclear Information System (INIS)

    We study the implications of the LHC diphoton and Z+photon Higgs signals on the Higgs triplet model with Y=0, which predicts two neutral CP-even Higgs bosons h, H and a pair of charged Higgs H±. We discuss three different scenarios: (i) the observed boson is the light Higgs boson h; (ii) it is the heavy Higgs boson H; (iii) the observed signal is from the almost degenerate h and H. We find that the inclusive Higgs diphoton rates in the first two scenarios can be enhanced or suppressed compared to the SM value, which can respectively fit the ATLAS and CMS diphoton data within 1σ range. The inclusive ZZ∗ rates are suppressed, which are outside 1σ range of ATLAS data and within 1σ range of CMS data. Meanwhile, another CP-even Higgs boson production rate can be suppressed enough not to be observed at the collider. For the third scenario, the Higgs diphoton rate is suppressed, which is outside 1σ range of ATLAS data, and the ZZ∗ rate equals to SM value approximately. In addition, we find that the two rates of h→γγ and h→Zγ have the positive correlations for the three scenarios

  13. Multi-Lepton Signatures of the Triplet Like Charged Higgs at the LHC

    CERN Document Server

    Bandyopadhyay, Priyotosh; Keceli, Asli Sabanci

    2014-01-01

    We study multi-lepton signatures of the triplet like charged Higgs at the LHC in the context of $Y=0$ triplet extended supersymmetric model (TESSM). In TESSM the $h_i^\\pm W^\\mp Z$ coupling appears at tree level when the triplet vacuum expectation value is nonzero, and because of the coupling the charged Higgs decay channels as well as the production channels can dramatically change at the LHC. We show that for the triplet dominated charged Higgs the main production channels are no longer through the top decay or $gg$ and $gb$ fusions since these are very suppressed due to the lack of triplet-SM fermion coupling. In the numerical analysis, we consider also other possible production channels some of which have additional contributions from the diagrams containing $h_i^\\pm W^\\mp Z$ vertex. We investigate the decay channels of a triplet like light charged Higgs ($m_{h_1^{\\pm}}\\leq 200$ GeV) and show that depending on the triplet component, the charged Higgs can substantially decay to $W^\\pm Z$. We further examine...

  14. Higher triplet state of fullerene C70 revealed by electron spin relaxation

    International Nuclear Information System (INIS)

    Spin-lattice relaxation times T1 of photoexcited triplets 3C70 in glassy decalin were obtained from electron spin echo inversion recovery dependences. In the range 30–100 K, the temperature dependence of T1 was fitted by the Arrhenius law with an activation energy of 172 cm−1. This indicates that the dominant relaxation process of 3C70 is described by an Orbach-Aminov mechanism involving the higher triplet state t2 which lies 172 cm−1 above the lowest triplet state t1. Chemical modification of C70 fullerene not only decreases the intrinsic triplet lifetime by about ten times but also increases T1 by several orders of magnitude. The reason for this is the presence of a low-lying excited triplet state in 3C70 and its absence in triplet C70 derivatives. The presence of the higher triplet state in C70 is in good agreement with the previous results from phosphorescence spectroscopy

  15. Higher triplet state of fullerene C{sub 70} revealed by electron spin relaxation

    Energy Technology Data Exchange (ETDEWEB)

    Uvarov, Mikhail N., E-mail: uvarov@kinetics.nsc.ru [Voevodsky Institute of Chemical Kinetics and Combustion, Siberian Branch of Russian Academy of Sciences, Institutskaya St. 3, 630090 Novosibirsk (Russian Federation); Behrends, Jan [Berlin Joint EPR Lab, Freie Universität Berlin, Arnimallee 14, 14195 Berlin (Germany); Kulik, Leonid V. [Voevodsky Institute of Chemical Kinetics and Combustion, Siberian Branch of Russian Academy of Sciences, Institutskaya St. 3, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, Pirogova St. 2, Novosibirsk (Russian Federation)

    2015-12-28

    Spin-lattice relaxation times T{sub 1} of photoexcited triplets {sup 3}C{sub 70} in glassy decalin were obtained from electron spin echo inversion recovery dependences. In the range 30–100 K, the temperature dependence of T{sub 1} was fitted by the Arrhenius law with an activation energy of 172 cm{sup −1}. This indicates that the dominant relaxation process of {sup 3}C{sub 70} is described by an Orbach-Aminov mechanism involving the higher triplet state t{sub 2} which lies 172 cm{sup −1} above the lowest triplet state t{sub 1}. Chemical modification of C{sub 70} fullerene not only decreases the intrinsic triplet lifetime by about ten times but also increases T{sub 1} by several orders of magnitude. The reason for this is the presence of a low-lying excited triplet state in {sup 3}C{sub 70} and its absence in triplet C{sub 70} derivatives. The presence of the higher triplet state in C{sub 70} is in good agreement with the previous results from phosphorescence spectroscopy.

  16. First Metallicty Distribution From CaT Spectroscopy of RGB Stars in the Dwarf Irregular Galaxy WLM

    Science.gov (United States)

    Leaman, Ryan; Cole, A.; Venn, K.; Tolstoy, E.; Irwin, M.; Szeifert, T.

    2007-07-01

    A metallicity distribution for the central bar region of the dwarf irregular galaxy WLM is presented from VLT FORS2 spectra of 46 red giant stars, as well as radial velocities for the member stars in this field. The [Fe/H] values were derived using the near infrared Ca II triplet lines as a tracer of metallicity (see Grocholski et al. 2006, Rutledge et al. 1997) and is conformed to a metallicity scale with the aid of four calibrating globular clusters. Although limited by small number statistics in this preliminary release, the ability to study the metallicitiy with respect to velocity and physical location of the member stars is invaluable in helping to characterize the formation and enrichment history of these kind of stellar populations - as has been found from CaT analysis of RGB stars in the Sculptor and Fornax galaxies. (Tolstoy et al. 2004, Battaglia et al. 2006) Specifically, the metallicty distribution for the WLM stellar population(s) can be tied to the recent HST star formation history study (Dolphin, 2000) which places estimates on the frequency and duration of star formation episodes in WLM. The isolated nature of WLM allows a unique opportunity to analyze the enrichment and star formation history of a low luminosity stellar population, which presumably has had a less complicated evolution due to minimal local group interactions. Research for this study was funded in part by NSERC Discovery Grant Program #327292-06.

  17. El sitio Bajo del Coypar II: Las evidencias más tempranas (CA. 1000 AP del proceso agropastoril en la Puna Meridional Argentina (Antofagasta de la Sierra, Catamarca

    Directory of Open Access Journals (Sweden)

    Silvina Vigliani

    2005-01-01

    Full Text Available El sitio Bajo del Coypar II (BC II es un conjunto de estructuras de pequeñas dimensiones ubicado sobre una saliente de la ladera de los cerros del Coypar, frente y alrededor del cual se distribuye una gran superficie de campos de cultivo prehispánicos, (Bajo del Coypar I de aproximadamente 1000 ha. En un trabajo anterior se postuló que este amplio sistema de producción agrícola se originó hacia el final del proceso regional tardío (ca. 1300 AP en asociación con el crecimiento del principal centro habitacional de la región, La Alumbrera (Olivera et.al, 1994 y que luego fue apropiado y ampliado por el Incario. En el presente trabajo se plantean tres objetivos generales: conocer el tipo de actividades que se realizaban en el conjunto de estructuras de BC II, establecer la asociación que había entre este conjunto de estructuras y el sistema de producción agrícola e identificar posibles cambios en el uso del espacio a lo largo del tiempo. En un principio se pensó que Bajo del Coypar II formaba parte de la ampliación del espacio productivo implementada por el Imperio Incaico. Las investigaciones llevadas a cabo en el mismo permitieron determinar que efectivamente hacia las etapas más tardías y en asociación con el Incario había una estrecha relación con el sector agrícola, evidenciado en una alta frecuencia de vasijas para el almacenaje y/o el procesamiento de sustancias secas. Sin embargo, también revelaron ocupaciones más tempranas vinculadas a grupos o unidades domésticas con un desarrollo creciente de las prácticas agrícolas. De este modo, la actividad agro-pastoril fue, en este sector de la Puna meridional, mucho más temprana de lo que pensábamos.

  18. Unveiling The Sigma-Discrepancy II: Revisiting the Evolution of ULIRGs & The Origin of Quasars

    CERN Document Server

    Rothberg, Barry; Rodrigues, Myriam; Sanders, David B

    2013-01-01

    We present the first central velocity dispersions (sigma_o) measured from the 0.85 micron Calcium II Triplet (CaT) for 8 advanced (i.e. single nuclei) local (z < 0.15) Ultraluminous Infrared Galaxies (ULIRGs). First, these measurements are used to test the prediction that the "sigma-Discrepancy," in which the CaT sigma_o is systematically larger than the sigma_o obtained from the 1.6 or 2.3 micron stellar CO band-heads, extends to ULIRG luminosities. Next, we combine the CaT data with rest-frame I-band photometry obtained from archival Hubble Space Telescope data and the Sloan Digital Sky Survey (SDSS) to derive dynamical properties for the 8 ULIRGs. These are then compared to the dynamical properties of 9,255 elliptical galaxies from the SDSS within the same redshift volume and of a relatively nearby (z < 0.4) sample of 53 QSO host galaxies. A comparison is also made between the I-band and H-band dynamical properties of the ULIRGs. We find four key results: 1) the sigma-Discrepancy extends to ULIRG lum...

  19. Inhibitors of the Ca2+/calmodulin-dependent protein kinase phosphatase family (CaMKP and CaMKP-N)

    International Nuclear Information System (INIS)

    Ca2+/calmodulin-dependent protein kinase phosphatase (CaMKP) and its nuclear isoform CaMKP-N are unique Ser/Thr protein phosphatases that negatively regulate the Ca2+/calmodulin-dependent protein kinase (CaMK) cascade by dephosphorylating multifunctional CaMKI, II, and IV. However, the lack of specific inhibitors of these phosphatases has hampered studies on these enzymes in vivo. In an attempt to obtain specific inhibitors, we searched inhibitory compounds and found that Evans Blue and Chicago Sky Blue 6B served as effective inhibitors for CaMKP. These compounds also inhibited CaMKP-N, but inhibited neither protein phosphatase 2C, another member of PPM family phosphatase, nor calcineurin, a typical PPP family phosphatase. The minimum structure required for the inhibition was 1-amino-8-naphthol-4-sulfonic acid. When Neuro2a cells cotransfected with CaMKIV and CaMKP-N were treated with these compounds, the dephosphorylation of CaMKIV was strongly suppressed, suggesting that these compounds could be used as potent inhibitors of CaMKP and CaMKP-N in vivo as well as in vitro

  20. Isolation of proximity-induced triplet pairing channel in a superconductor/ferromagnet spin valve

    OpenAIRE

    Leksin, P. V.; Garifyanov, N. N.; Kamashev, A. A.; Validov, A. A.; Fominov, Ya. V.; Schumann, J.; KATAEV V.; J. Thomas; Büchner, B.; Garifullin, I. A.

    2015-01-01

    We have studied the proximity-induced superconducting triplet pairing in CoO$_x$/Py1/Cu/Py2/Cu/Pb spin-valve structure (where Py = Ni$_{0.81}$Fe$_{0.19}$). By optimizing the parameters of this structure we found a triplet channel assisted full switching between the normal and superconducting states. To observe an "isolated" triplet spin-valve effect we exploited the oscillatory feature of the magnitude of the ordinary spin-valve effect $\\Delta T_c$ in the dependence of the Py2-layer thickness...

  1. Asymptomatic (Subclinical Meningitis in One of Premature Triplets with Simultaneous Enteroviral Meningitis: A Case Report

    Directory of Open Access Journals (Sweden)

    Ashish Gupta

    2012-11-01

    Full Text Available Most enterovirus infection in the neonate and young infant is asymptomatic, but serious disease may occur, especially if acquired perinatally. We report the first case, to our knowledge, of asymptomatic enterovirus aseptic meningitis, and of concurrent enterovirus aseptic meningitis in premature triplets. Ten-week-old, 31-week-estimated gestational age premature triplet boys were diagnosed with enterovirus aseptic meningitis on the same day. Two of the triplets developed symptoms on the day of admission, while the third remained symptom free throughout the infection. All three recovered completely and are healthy more than a decade later.

  2. Classical and quantum 'EPR'-spin correlations in the triplet state

    International Nuclear Information System (INIS)

    Quantum correlations and joint probabilities in the triplet state as well as the correlations of components of two correlated classical spin vectors, are evaluated. Correlations in the states with |Stotz|=1 are different from correlations in the state with Stotz=0 which may serve to distinguish different states of the triplet. As in the singlet case, we can reproduce quantum correlations by correlated classical spin vectors which also provide a precision of the notion of ''parallel spins''. Triplet state correlations could in principle be measured, for example, in the decay reaction J/ψ → e+e- for which there is a sufficiently large branching ratio. (author). 12 refs

  3. Orbifold Grand Unification: A Solution to the Doublet-Triplet Problem

    CERN Document Server

    Jia, Bei

    2014-01-01

    To solve the doublet-triplet splitting problem in SU(5) grand unified theories, we propose a four dimensional orbifold grand unified theory by acting Z2 on the SU(5) gauge group. Without an adjoint Higgs, the orbifold procedure breaks the SU(5) gauge symmetry down to the standard model gauge group, and removes the triplet component of the fundamental SU(5) Higgs. In the supersymmetric framework, we show that the orbifold procedure removes two triplet superfields of the Higgs multiplets and leaves us with the minimal supersymmetric standard model, which also solves the hierarchy problem and realizes gauge coupling unification. We also discuss possible UV completions of the orbifold theories.

  4. Formation of the O I resonance triplet and intercombination doublet in the solar chromosphere

    Science.gov (United States)

    Skelton, D. L.; Shine, R. A.

    1982-01-01

    Spectrum synthesis calculations are presented for the O I resonance triplet at 1304 A and the intercombination doublet at 1358 A for the solar atmosphere and several variants, allowing for triplet fluorescence by the Ly-beta emission of H I. Profiles, synthesized from a seven-level plus continuum O I atom are compared to observations taken with the high-resolution spectrometer on OSO 8. It is found that the O I triplet emission is dominated by the Ly-beta fluorescence and that the agreement between observations and profiles computed with current chromospheric models is much improved over earlier studies.

  5. Understanding the Photoreactivity of Dissolved Organic Carbon in Natural Waters: The Role of the Triplet Excited-State of Allochthonous and Autochthonous DOC

    Science.gov (United States)

    Cottrell, B. A.; Timko, S. A.; Robinson, A. K.; Weiden, L. M.; Cooper, W.

    2012-12-01

    The photochemical reactivity of DOC in sunlit waters is a major factor for the in situ processing of DOC itself and trace contaminants in streams, lakes and the ocean. There is an increasing interest in the use of wetlands to mitigate contaminant removal. Laser flash photolysis is used to determine the reaction rate constants of dissolved organic carbon (DOC) with emerging contaminants in natural waters. DOC, produced by the decomposition of plant and microbial material, is one of the most complex naturally occurring mixtures. DOC plays a major role in the global carbon cycle, the sequestration and transport of trace chemicals and contaminants, and the biogeochemistry of natural waters. Hydrolysis, direct photolysis and reactions with singlet oxygen and the hydroxyl radical account for up to 25% of the photo reactivity of natural organic matter. The remaining 75% is attributed to reactions with the triplet-excited state of DOC (3DOC*). In this study, 1H NMR is used to characterize DOC from the Black River (NC), the San Joaquin Wetlands (Irvine, CA), and coastal seawater (Crystal Cove, CA). These sites encompass both allochthonous and autochthonous organic matter from catchment, wetlands, and marine waters. We then determine the reaction rate constants of known triplet state reactants and pharmaceuticals with the 3DOC* in the natural waters and with the DOC isolated by solid phase extraction. Studies of 3DOC* could provide a measure of DOC reactivity, essential in the design of constructed wetlands for contaminant removal.

  6. The DART imaging and CaT survey of the Fornax Dwarf Spheroidal Galaxy

    CERN Document Server

    Battaglia, G; Helmi, A; Irwin, M J; Letarte, B; Jablonka, P; Hill, V; Venn, K A; Shetrone, M D; Arimoto, N; Primas, F; Kaufer, A; François, P; Szeifert, T; Abel, T; Sadakane, K

    2006-01-01

    As part of the DART project we have used the ESO/2.2m Wide Field Imager in conjunction with the VLT/FLAMES GIRAFFE spectrograph to study the detailed properties of the resolved stellar population of the Fornax dwarf spheroidal galaxy out to and beyond its tidal radius. We re-derived the structural parameters of the Fornax dwarf spheroidal using our wide field imaging covering the galaxy out to its tidal radius, and analysed the spatial distribution of the Fornax stars of different ages as selected from Colour-Magnitude Diagram analysis. We have obtained accurate velocities and metallicities from spectra in the CaII triplet wavelength region for 562 Red Giant Branch stars which have velocities consistent with membership in Fornax dwarf spheroidal. We have found evidence for the presence of at least three distinct stellar components: a young population (few 100 Myr old) concentrated in the centre of the galaxy, visible as a Main Sequence in the Colour-Magnitude Diagram; an intermediate age population (2-8 Gyr o...

  7. Singlet-Triplet Gaps of Cobalt Nitrosyls: Insights from Tropocoronand Complexes.

    Science.gov (United States)

    Hopmann, Kathrin H; Conradie, Jeanet; Tangen, Espen; Tonzetich, Zachary J; Lippard, Stephen J; Ghosh, Abhik

    2015-08-01

    A density functional theory (DFT) study of {CoNO}(8) cobalt nitrosyl complexes containing the [n,n]tropocoronand ligand (TC-n,n) has revealed a sharp reduction of singlet-triplet gaps as the structures change from near-square-pyramidal (for n = 3) to trigonal-bipyramidal with an equatorial NO (for n = 5, 6). An experimental reinvestigation of [Co(TC-3,3)(NO)] has confirmed that it is not paramagnetic, as originally reported, but diamagnetic, like all other {CoNO}(8) complexes. Furthermore, DFT calculations indicate a substantial singlet-triplet gap of about half an eV or higher for this complex. At the other end of the series, low-energy, thermally accessible triplet states are predicted for [Co(TC-6,6)(NO)]. Enhanced triplet-state reactivity may well provide a partial explanation for the failure to isolate this compound as a stable species. PMID:26203786

  8. The structure of strongly additive states and Markov triplets on the CAR algebra

    CERN Document Server

    Jencova, Anna

    2010-01-01

    We find a characterization of states satisfying equality in strong subadditivity of entropy and of Markov triplets on the CAR algebra. For even states, a more detailed structure of the density matrix is given.

  9. Design and construction of triplet atmospheric cold plasma jet for sterilization

    Directory of Open Access Journals (Sweden)

    F. Sohbatzadeh

    2014-03-01

    Full Text Available In this paper, construction of triplet atmospheric plasma jet using argon, air, oxygen and nitrogen gases is reported. Bactericidal effect of the plasma jet is also investigated. To that end, longitudinal geometric configuration for the electrodes was chosen because it would increase the jet length. Electrical characteristics, jet length dependencies on the applied voltage and gas flow rate were decided, experimentally. Relative concentrations of chemical reactive species such as ozone, atomic oxygen, NOx compounds and hydroxyl were measured using optical emission spectroscopy. It was seen that atomic oxygen and ozone concentrations with triplet plasma jet are more than the concentration of single plasma jet. Triplet plasma jet was also used for sterilization of solid and liquid surfaces to disinfect gram-negative and gram-positive Escherichia coli and Streptococcus pyogenes bacteria. The results verified the effectiveness of the triplet plasma jet for killing bacteria.

  10. Conjoined twins in a monochorionic triplet pregnancy after in vitro fertilization: a case report

    Directory of Open Access Journals (Sweden)

    Marzieh Talebian

    2015-11-01

    Full Text Available Background: Monozygotic monochorionic triplet pregnancy with conjoined twins is a very rare condition and is associated with many complications. Case: In this study, we describe a monochorionic–diamniotic triplet pregnancy after in vitro fertilization with an intracytoplasmic sperm injection. At a gestational age of 6 weeks and 4 days of pregnancy one gestational sac was observed, and at a gestational age of 12 weeks and 2 days, triplets with conjoined twins were diagnosed. After consulting with the parents, they chose fetal reduction of the conjoined twins. Selective feticide was successfully performed by radiofrequency ablation at 16 weeks of pregnancy. Unfortunately, the day after the procedure, the membrane ruptured, and 1 week later, all fetuses and placenta were spontaneously aborted. Conclusion: Monochorionic triplet pregnancy with conjoined twins is very rare. These pregnancies are associated with very serious complications. Intra cytoplasmic sperm injection increases the rate of monozygotic twinning and conjoined twins. Counseling with parents before IVF is very important.

  11. Hadronic production of light color-triplet Higgs bosons: An alternative signature for grand unified theories

    International Nuclear Information System (INIS)

    The conventional signature for grand unified theories (GUTs) is proton decay. Recently, some models in extra dimensions or with specific discrete symmetries, which aim at solving the doublet-triplet problem, allow a color triplet in the TeV mass region by suppressing the Yukawa couplings of the triplets to matter fermions. We study the hadronic production and detection of these TeV colored Higgs bosons as an alternative signature for GUTs; they would behave like massive stable charged particles in particle detectors, producing the striking signature of a charged track in the central tracking system and being ionized in the outer muon chamber. We find that the CERN LHC is sensitive to a colored Higgs boson up to about 1.5 TeV. If the color triplets are stable on a cosmological time scale, they may constitute an interesting fraction of the dark matter

  12. Amplitude Control of the Spin-Triplet Supercurrent in S /F /S Josephson Junctions

    Science.gov (United States)

    Martinez, William M.; Pratt, W. P.; Birge, Norman O.

    2016-02-01

    Josephson junctions made with conventional s -wave superconductors and containing multiple layers of ferromagnetic materials can carry spin-triplet supercurrent in the presence of certain types of magnetic inhomogeneity. In junctions containing three ferromagnetic layers, the triplet supercurrent is predicted to be maximal when the magnetizations of the adjacent layers are orthogonal, and zero when the magnetizations of any two adjacent layers are parallel. Here we demonstrate on-off control of the spin-triplet supercurrent in such junctions, achieved by rotating the magnetization direction of one of the three layers by 90°. We obtain "on-off" ratios of 5, 7, and 19 for the supercurrent in the three samples that have been studied so far. These observations directly confirm one of the most salient predictions of the theory, and they pave the way for applications of spin-triplet Josephson junctions in the nascent area of "superconducting spintronics".

  13. Efficient photon triplet generation in integrated nanophotonic waveguides.

    Science.gov (United States)

    Moebius, Michael G; Herrera, Felipe; Griesse-Nascimento, Sarah; Reshef, Orad; Evans, Christopher C; Guerreschi, Gian Giacomo; Aspuru-Guzik, Alán; Mazur, Eric

    2016-05-01

    Generation of entangled photons in nonlinear media constitutes a basic building block of modern photonic quantum technology. Current optical materials are severely limited in their ability to produce three or more entangled photons in a single event due to weak nonlinearities and challenges achieving phase-matching. We use integrated nanophotonics to enhance nonlinear interactions and develop protocols to design multimode waveguides that enable sustained phase-matching for third-order spontaneous parametric down-conversion (TOSPDC). We predict a generation efficiency of 0.13 triplets/s/mW of pump power in TiO2-based integrated waveguides, an order of magnitude higher than previous theoretical and experimental demonstrations. We experimentally verify our device design methods in TiO2 waveguides using third-harmonic generation (THG), the reverse process of TOSPDC that is subject to the same phase-matching constraints. We finally discuss the effect of finite detector bandwidth and photon losses on the energy-time coherence properties of the expected TOSPDC source. PMID:27137604

  14. The 3-3-1 model with inert scalar triplet

    CERN Document Server

    Dong, P V; Soa, D V

    2013-01-01

    We show that the typical 3-3-1 models are only self-consistent if they contain interactions explicitly violating the lepton number. The 3-3-1 model with right-handed neutrinos can by itself work as an economical 3-3-1 model as a natural recognition of the above criteria while it also results an inert scalar triplet (\\eta) responsible for dark matter. This is ensured by a Z_2 symmetry (assigned so that only \\eta is odd while all other multiplets which perform the economical 3-3-1 model are even), which is not broken by the vacuum. The dark matter candidate (H_\\eta) contained in \\eta transforms as a singlet under the standard model symmetry and being naturally heavy. The H_\\eta relic density and direct detection cross-section will get right values when the H_\\eta mass is in TeV range as expected. The model predicts the H_\\eta mass m_{H_\\eta}=\\la_5 \\times 2 TeV and the H_\\eta-nucleon scattering cross-section \\sigma_{H_\\eta-N}=1.56 \\times 10^{-44} cm^2, provided that the new neutral Higgs boson is heavy enough th...

  15. Potential energy surface of triplet N2O2

    International Nuclear Information System (INIS)

    We present a global ground-state triplet potential energy surface for the N2O2 system that is suitable for treating high-energy vibrational-rotational energy transfer and collision-induced dissociation. The surface is based on multi-state complete-active-space second-order perturbation theory/minimally augmented correlation-consistent polarized valence triple-zeta electronic structure calculations plus dynamically scaled external correlation. In the multireference calculations, the active space has 14 electrons in 12 orbitals. The calculations cover nine arrangements corresponding to dissociative diatom-diatom collisions of N2, O2, and nitric oxide (NO), the interaction of a triatomic molecule (N2O and NO2) with the fourth atom, and the interaction of a diatomic molecule with a single atom (i.e., the triatomic subsystems). The global ground-state potential energy surface was obtained by fitting the many-body interaction to 54 889 electronic structure data points with a fitting function that is a permutationally invariant polynomial in terms of bond-order functions of the six interatomic distances

  16. Potential energy surface of triplet N2O2.

    Science.gov (United States)

    Varga, Zoltan; Meana-Pañeda, Rubén; Song, Guoliang; Paukku, Yuliya; Truhlar, Donald G

    2016-01-14

    We present a global ground-state triplet potential energy surface for the N2O2 system that is suitable for treating high-energy vibrational-rotational energy transfer and collision-induced dissociation. The surface is based on multi-state complete-active-space second-order perturbation theory/minimally augmented correlation-consistent polarized valence triple-zeta electronic structure calculations plus dynamically scaled external correlation. In the multireference calculations, the active space has 14 electrons in 12 orbitals. The calculations cover nine arrangements corresponding to dissociative diatom-diatom collisions of N2, O2, and nitric oxide (NO), the interaction of a triatomic molecule (N2O and NO2) with the fourth atom, and the interaction of a diatomic molecule with a single atom (i.e., the triatomic subsystems). The global ground-state potential energy surface was obtained by fitting the many-body interaction to 54 889 electronic structure data points with a fitting function that is a permutationally invariant polynomial in terms of bond-order functions of the six interatomic distances. PMID:26772574

  17. Antiferromagnetism in Pr3In: Singlet/triplet physics withfrustration

    Energy Technology Data Exchange (ETDEWEB)

    Christianson, A.D.; Lawrence, J.M.; Zarestky, J.L.; Suzuki, H.; Thompson, J.D.; Hundley, M.F.; Sarrao, J.L.; Booth, C.H.; Antonio, D.; Cornelius, A.L.

    2004-11-18

    We present neutron diffraction, magnetic susceptibility and specific heat data for a single-crystal sample of the cubic (Cu{sub 3}Au structure) compound Pr{sub 3}In. This compound is believed to have a singlet ({Lambda}{sub 1}) groundstate and a low-lying triplet ({Lambda}{sub 4}) excited state. In addition, nearest-neighbor antiferromagnetic interactions are frustrated in this structure. Antiferromagnetic order occurs below T{sub N} = 12K with propagation vector (0, 0, 0.5 {center_dot}{delta}) where {delta} {approx} 1/12. The neutron diffraction results can be approximated with the following model: ferromagnetic sheets from each of the three Pr sites alternate in sign along the propagation direction with a twelve-unit-cell square-wave modulation. The three moments of the unit cell of 1 {micro}{sub B} magnitude are aligned so as to sum to zero as expected for nearest-neighbor antiferromagnetic interactions on a triangle. The magnetic susceptibility indicates that in addition to the antiferromagnetic transition at 12K, there is a transition near 70K below which there is a small (0.005 {micro}{sub B}) ferromagnetic moment. There is considerable field and sample dependence to these transitions. The specific heat data show almost no anomaly at T{sub N} = 12K. This may be a consequence of the induced moment in the {Lambda}{sub 1} singlet, but may also be a sample-dependent effect.

  18. Radiative corrections to the Higgs couplings in the triplet model

    International Nuclear Information System (INIS)

    The feature of extended Higgs models can appear in the pattern of deviations from the Standard Model (SM) predictions in coupling constants of the SM-like Higgs boson (h). We can thus discriminate extended Higgs models by precisely measuring the pattern of deviations in the coupling constants of h, even when extra bosons are not found directly. In order to compare the theoretical predictions to the future precision data at the ILC, we must evaluate the theoretical predictions with radiative corrections in various extended Higgs models. In this paper, we give our comprehensive study for radiative corrections to various Higgs boson couplings of h in the minimal Higgs triplet model (HTM). First, we define renormalization conditions in the model, and we calculate the Higgs coupling; gγγ, hWW, hZZ and hhh at the one loop level. We then evaluate deviations in coupling constants of the SM-like Higgs boson from the predictions in the SM. We find that one-loop contributions to these couplings are substantial as compared to their expected measurement accuracies at the ILC. Therefore the HTM has a possibility to be distinguished from the other models by comparing the pattern of deviations in the Higgs boson couplings.

  19. Noise filtering of composite pulses for singlet-triplet qubits.

    Science.gov (United States)

    Yang, Xu-Chen; Wang, Xin

    2016-01-01

    Semiconductor quantum dot spin qubits are promising candidates for quantum computing. In these systems, the dynamically corrected gates offer considerable reduction of gate errors and are therefore of great interest both theoretically and experimentally. They are, however, designed under the static-noise model and may be considered as low-frequency filters. In this work, we perform a comprehensive theoretical study of the response of a type of dynamically corrected gates, namely the supcode for singlet-triplet qubits, to realistic 1/f noises with frequency spectra 1/ω(α). Through randomized benchmarking, we have found that supcode offers improvement of the gate fidelity for α  1 and the improvement becomes exponentially more pronounced with the increase of the noise exponent in the range 1  α ≤ 3 studied. On the other hand, for small α, supcode will not offer any improvement. The δJ-supcode, specifically designed for systems where the nuclear noise is absent, is found to offer additional error reduction than the full supcode for charge noises. The computed filter transfer functions of the supcode gates are also presented. PMID:27383129

  20. Radiative corrections to the Higgs couplings in the triplet model

    CERN Document Server

    Kikuchi, Mariko

    2013-01-01

    The feature of extended Higgs models can appear in the pattern of deviations from the Standard Model (SM) predictions in coupling constants of the SM-like Higgs boson ($h$). We can thus discriminate extended Higgs models by precisely measuring the pattern of deviations in the coupling constants of $h$, even when extra bosons are not found directly. In order to compare the theoretical predictions to the future precision data at the ILC, we must evaluate the theoretical predictions with radiative corrections in various extended Higgs models. In this talk, we give our comprehensive study for radiative corrections to various Higgs boson couplings of $h$ in the minimal Higgs triplet model (HTM). First, we define renormalization conditions in the model, and we calculate the Higgs coupling; $g\\gamma\\gamma, hWW, hZZ$ and $hhh$ at the one loop level. We then evaluate deviations in coupling constants of the SM-like Higgs boson from the predictions in the SM. We find that one-loop contributions to these couplings are su...

  1. Low energy 40Ca + 40Ca collisions

    International Nuclear Information System (INIS)

    This paper deals with the classical microscopic study of 40Ca + 40Ca collisions. Fusion cross-sections (σsub(CF)) for various incident energies, energy variations with time, shape deformation and the life time of resonance scattering (T) have been studied. Comparison of 40Ca + 40Ca results with those of 16O + 16O have also been made. (author)

  2. Sensitized Triplet Formation of Chlorophyll-A and beta-Carotene

    DEFF Research Database (Denmark)

    Jensen, Nina Mejlhede; Wilbrandt, Robert Walter; Pagsberg, Palle Bjørn

    1980-01-01

    The naphthalene-sensitized formation of triplet excited chlorophyll-a (Chl-a) and all-transß-carotene has been studied by pulse radiolysis. The rate constants for transfer of triplet energy from naphthalene to Chl-a and all-transß-carotene in benzene at 25°C are (3.6 ± 0.6)·109M-1 s-1 and (10.7 ±...

  3. Spin-triplet supercurrent carried by quantum Hall edge states through a Josephson junction

    OpenAIRE

    van Ostaay, J. A. M.; Akhmerov, A. R.; Beenakker, C. W. J.

    2011-01-01

    We show that a spin-polarized Landau level in a two-dimensional electron gas can carry a spin-triplet supercurrent between two spin-singlet superconductors. The supercurrent results from the interplay of Andreev reflection and Rashba spin-orbit coupling at the normal--superconductor (NS) interface. We contrast the current-phase relationship and the Fraunhofer oscillations of the spin-triplet and spin-singlet Josephson effect in the lowest Landau level, and find qualitative differences.

  4. Spin-triplet supercurrent carried by quantum Hall edge states through a Josephson junction

    Science.gov (United States)

    van Ostaay, J. A. M.; Akhmerov, A. R.; Beenakker, C. W. J.

    2011-05-01

    We show that a spin-polarized Landau level in a two-dimensional electron gas can carry a spin-triplet supercurrent between two spin-singlet superconductors. The supercurrent results from the interplay of Andreev reflection and Rashba spin-orbit coupling at the normal-superconductor (NS) interface. We contrast the current-phase relationship and the Fraunhofer oscillations of the spin-triplet and spin-singlet Josephson effect in the lowest Landau level and find qualitative differences.

  5. Damages induced in lambda phage DNA by enzyme-generated triplet acetone

    International Nuclear Information System (INIS)

    Exposure of lambda phage to triplet acetone, generated during the aerobic oxidation of isobutanal by peroxidase, leads to genome lesions. The majority of these lesions are detected as DNA single-strand breaks only in alkaline conditions, so true breaks were not observed. Also, no sites sensitive to UV-endonuclease from Micrococcus luteus were found in DNA from treated phage. The participation of triplet acetone in the generation of such DNA damage is discussed. (Author)

  6. Superfluid phases of triplet pairing and rapid cooling of the neutron star in Cassiopeia A

    OpenAIRE

    Leinson, Lev B.

    2014-01-01

    In a simple model it is demonstrated that the neutron star surface temperature evolution is sensitive to the phase state of the triplet superfluid condensate. A multicomponent triplet pairing of superfluid neutrons in the core of a neutron star with participation of several magnetic quantum numbers leads to neutrino energy losses exceeding the losses from the unicomponent pairing. A phase transition of the neutron condensate into the multicomponent state triggers more rapid cooling of superfl...

  7. Differences between CO- and calcium triplet-derived velocity dispersions in spiral galaxies: evidence for central star formation?

    CERN Document Server

    Riffel, Rogemar A; Mason, Rachel; Rodriguez-Ardila, Alberto; Martins, Lucimara; Riffel, Rogerio; Diaz, Ruben; Colina, Luis; Alonso-Herrero, Almudena; Flohic, Helene; Martin, Omaira Gonzalez; Lira, Paulina; McDermid, Richard; Almeida, Cristina Ramos; Schiavon, Ricardo; Thanjavur, Karun; Dutra, Daniel Ruschel; Winge, Claudia; Perlman, Eric

    2014-01-01

    We examine the stellar velocity dispersions (sigma) of a sample of 48 galaxies, 35 of which are spirals, from the Palomar nearby galaxy survey. It is known that for ultra-luminous infrared galaxies (ULIRGs) and merger remnants thesigma derived from the near-infrared CO band-heads is smaller than that measured from optical lines, while no discrepancy between these measurements is found for early-type galaxies. No such studies are available for spiral galaxies - the subject of this paper. We used cross-dispersed spectroscopic data obtained with the Gemini Near-Infrared Spectrograph (GNIRS), with spectral coverage from 0.85 to 2.5um, to obtain sigma measurements from the 2.29 $\\mu$m CO band-heads (sigma_{CO}), and the 0.85 um calcium triplet (sigma_{CaT}). For the spiral galaxies in the sample, we found that sigma_{CO} is smaller than sigma_{CaT}, with a mean fractional difference of 14.3%. The best fit to the data is given by sigma_{opt} = (46.0+/-18.1) + (0.85+/-0.12)sigma_{CO}. This "sigma discrepancy" may be...

  8. The excited spin-triplet state of a charged exciton in quantum dots

    Science.gov (United States)

    Molas, M. R.; Nicolet, A. A. L.; Piętka, B.; Babiński, A.; Potemski, M.

    2016-09-01

    We report on spectroscopic studies of resonances related to ladder of states of a charged exciton in single GaAlAs/AlAs quantum dot structures. Polarization-resolved photoluminescence, photoluminescence excitation and photon-correlation measurements were performed at low (T  =  4.2 K) temperature also in magnetic field applied in Faraday configuration. The investigated resonances are assigned to three different configurations of a positively charged exciton. Together with a singlet ground state and a conventional triplet state (involving an electron from the ground state electronic s-shell), an excited triplet state, which involved an electron from the excited electronic p-shell was identified in single dots. The appearance of an emission line related to the latter complex is due to a partially suppressed electron relaxation in the investigated dots. An analysis of this emission line allows us to scrupulously determine properties of the excited triplet state and compare them with those of the conventional triplet state. Both triplets exhibit similar patterns of anisotropic fine structure and Zeeman splitting, however their amplitudes significantly differ for those two states. Presented results emphasize the role of the symmetry of the electronic state on the properties of the triplet states of two holes  +  electron excitonic complex.

  9. Employing Core-Shell Quantum Dots as Triplet Sensitizers for Photon Upconversion.

    Science.gov (United States)

    Okumura, Keisuke; Mase, Kazuma; Yanai, Nobuhiro; Kimizuka, Nobuo

    2016-06-01

    A new family of surface-functionalized CdSe/ZnS core-shell quantum dots (csQD) has been developed, which work as triplet sensitizers for triplet-triplet annihilation-based photon upconversion (TTA-UC). The surface modification of csQD with acceptor molecules plays a key role in the efficient relay of the excited energy of csQD to emitter molecules in the bulk solution, where the generated emitter triplets undergo triplet-triplet annihilation that leads to photon upconversion. Interestingly, improved UC properties were achieved with the core-shell QDs compared with core-only CdSe QDs (cQD). The threshold excitation intensity, which is defined as the necessary irradiance to achieve efficient TTA process, decreases by more than a factor of four. Furthermore, the total UC quantum yield is enhanced more than 50-fold. These enhancements should be derived from better optical properties of csQD, in which the non-radiative surface recombination sites are passivated by the shell layer with wider bandgap. PMID:27121225

  10. The excited spin-triplet state of a charged exciton in quantum dots.

    Science.gov (United States)

    Molas, M R; Nicolet, A A L; Piętka, B; Babiński, A; Potemski, M

    2016-09-14

    We report on spectroscopic studies of resonances related to ladder of states of a charged exciton in single GaAlAs/AlAs quantum dot structures. Polarization-resolved photoluminescence, photoluminescence excitation and photon-correlation measurements were performed at low (T  =  4.2 K) temperature also in magnetic field applied in Faraday configuration. The investigated resonances are assigned to three different configurations of a positively charged exciton. Together with a singlet ground state and a conventional triplet state (involving an electron from the ground state electronic s-shell), an excited triplet state, which involved an electron from the excited electronic p-shell was identified in single dots. The appearance of an emission line related to the latter complex is due to a partially suppressed electron relaxation in the investigated dots. An analysis of this emission line allows us to scrupulously determine properties of the excited triplet state and compare them with those of the conventional triplet state. Both triplets exhibit similar patterns of anisotropic fine structure and Zeeman splitting, however their amplitudes significantly differ for those two states. Presented results emphasize the role of the symmetry of the electronic state on the properties of the triplet states of two holes  +  electron excitonic complex. PMID:27391126

  11. The trouble with triplets in biodiversity informatics: a data-driven case against current identifier practices.

    Directory of Open Access Journals (Sweden)

    Robert Guralnick

    Full Text Available The biodiversity informatics community has discussed aspirations and approaches for assigning globally unique identifiers (GUIDs to biocollections for nearly a decade. During that time, and despite misgivings, the de facto standard identifier has become the "Darwin Core Triplet", which is a concatenation of values for institution code, collection code, and catalog number associated with biocollections material. Our aim is not to rehash the challenging discussions regarding which GUID system in theory best supports the biodiversity informatics use case of discovering and linking digital data across the Internet, but how well we can link those data together at this moment, utilizing the current identifier schemes that have already been deployed. We gathered Darwin Core Triplets from a subset of VertNet records, along with vertebrate records from GenBank and the Barcode of Life Data System, in order to determine how Darwin Core Triplets are deployed "in the wild". We asked if those triplets follow the recommended structure and whether they provide an easy and unambiguous means to track from specimen records to genetic sequence records. We show that Darwin Core Triplets are often riddled with semantic and syntactic errors when deployed and curated in practice, despite specifications about how to construct them. Our results strongly suggest that Darwin Core Triplets that have not been carefully curated are not currently serving a useful role for relinking data. We briefly consider needed next steps to overcome current limitations.

  12. Magnetic Diagnostics of the Chromosphere with the Mg II h-k Lines

    CERN Document Server

    Alemán, Tanausú del Pino; Sainz, Rafael Manso

    2016-01-01

    We developed a numerical code for polarized radiative transfer in a plane-parallel geometry that implements a recent formulation of partially coherent scattering by polarized multi-term atoms in arbitrary magnetic field regimes. This code allows the realistic modeling of the scattering polarization of important chromospheric lines, such as the Mg II h-k doublet, the Ca II H-K doublet and IR triplet, and lines of the H I Lyman and Balmer series. We present explicit results of the Mg II h-k doublet in a weakly magnetized atmosphere (20-100 G). These confirm the importance of partial redistribution effects in the formation of these lines, as pointed out by previous work in the non-magnetic case. We show that the presence of a magnetic field can produce measurable modifications of the broadband linear polarization even for relatively small field strengths (~10 G), while the circular polarization remains well represented by the classical magnetograph formula. Both these results open an important new window for the...

  13. A chemical confirmation of the faint Boötes II dwarf spheroidal galaxy

    International Nuclear Information System (INIS)

    We present a chemical abundance study of the brightest confirmed member star of the ultra-faint dwarf galaxy Boötes II from Keck/HIRES high-resolution spectroscopy at moderate signal-to-noise ratios. At [Fe/H] = –2.93 ± 0.03(stat.) ± 0.17(sys.), this star chemically resembles metal-poor halo field stars and the signatures of other faint dwarf spheroidal galaxies at the same metallicities in that it shows enhanced [α/Fe] ratios, Solar Fe-peak element abundances, and low upper limits on the neutron-capture element Ba. Moreover, this star shows no chemical peculiarities in any of the eight elements we were able to measure. This implies that the chemical outliers found in other systems remain outliers pertaining to the unusual enrichment histories of the respective environments, while Boo II appears to have experienced an enrichment history typical of its very low mass. We also re-calibrated previous measurements of the galaxy's metallicity from the calcium triplet (CaT) and find a much lower value than reported before. The resulting broad metallicity spread, in excess of one dex, the very metal-poor mean, and the chemical abundance patterns of the present star imply that Boötes II is a low-mass, old, metal-poor dwarf galaxy and not an overdensity associated with the Sagittarius Stream as has been previously suggested based on its sky position and kinematics. The low, mean CaT metallicity of –2.7 dex falls right on the luminosity-metallicity relation delineated over four orders of magnitude from the more luminous to the faintest galaxies. Thus Boötes II's chemical enrichment appears representative of the galaxy's original mass, while tidal stripping and other mass loss mechanisms were probably not significant as for other low-mass satellites.

  14. Photophysics of Soret-Excited Tetrapyrroles in Solution. IV. Radiationless Decay and Triplet-Triplet Annihilation Investigated Using Tetraphenylporphinato Sn(IV)

    Science.gov (United States)

    Maiti, Manisankar; Danger, Brook R.; Steer, Ronald P.

    2009-09-01

    The S2 population decay rates and triplet-triplet annihilation efficiencies of Sn(IV)Cl2TPP have been measured in fluid solutions using its weak S2-S0 fluorescence as a metric. A detailed description of the excited-state photophysics of Sn(IV)Cl2TPP has allowed comparisons to be made between this rigid, D4h axially coordinated molecule and axially uncoordinated tetrapyrroles of greater flexibility and lower symmetry. S2-S1 internal conversion is the major S2 population decay path for Sn(IV)Cl2TPP as it is for the S2 states of all other d0 and d10 metalated tetrapyrroles. The S2 state of Sn(IV)Cl2TPP exhibits S2-S1 relaxation rates that follow the energy gap law of radiationless transition theory and are only slightly faster than those exhibited by MgTPP and the weak coupling limit. Differences in S2-S1 radiationless decay rates among the series MTPP (M = Mg, Zn, Cd, SnCl2) cannot be traced to differences in the displacements of the S2 and S1 potential surfaces. Instead, the most likely source of the large differences in S2-S1 radiationless decay rates between CdTPP and Sn(IV)Cl2TPP is the lower symmetry of the former (near C4v), which permits a much larger number of vibrations to participate in S2-S1 vibronic coupling. Triplet-triplet annihilation of the type 2T1 → S2 + S0 has been observed in Sn(IV)Cl2TPP for the first time, but is of substantially lower efficiency than seen in ZnTPP in noncoordinating solvents because of its shorter triplet lifetime and the shielding effects of its axial Cl ligands, which tend to block the short-range interaction needed for Dexter energy transfer.

  15. Competition between Singlet and Triplet Superconductivity in the Extended Hubbard Model with Exchange Interaction on a Square Lattice

    International Nuclear Information System (INIS)

    Phase boundary between spin singlet and triplet superconductivity in the extended Hubbard model with exchange interaction on a square lattice is calculated within meanfield approximation. Basically, antiferromagnetic exchange interaction J is advantageous for the singlet pairing, while ferromagnetic J prefers the triplet pairing. When off-site interaction V is repulsive, the singlet phase and the triplet phase are separated by normal state in the phase diagram against V and J. If V is effectively attractive, however, the singlet and triplet states can compete against each other. We calculate the phase boundary between singlet and triplet phase for various band filling. It is shown that the triplet phase penetrates rather deeply into antiferromagnetic exchange regime for lower band filling, whereas the penetration of the singlet phase is confined in a narrow range of ferromagnetic exchange regime.

  16. Selective Na+/Ca2+ exchanger inhibition prevents Ca2+ overload-induced triggered arrhythmias

    Science.gov (United States)

    Nagy, Norbert; Kormos, Anita; Kohajda, Zsófia; Szebeni, Áron; Szepesi, Judit; Pollesello, Piero; Levijoki, Jouko; Acsai, Károly; Virág, László; Nánási, Péter P; Papp, Julius Gy; Varró, András; Tóth, András

    2014-01-01

    Background and Purpose Augmented Na+/Ca2+ exchanger (NCX) activity may play a crucial role in cardiac arrhythmogenesis; however, data regarding the anti-arrhythmic efficacy of NCX inhibition are debatable. Feasible explanations could be the unsatisfactory selectivity of NCX inhibitors and/or the dependence of the experimental model on the degree of Ca2+i overload. Hence, we used NCX inhibitors SEA0400 and the more selective ORM10103 to evaluate the efficacy of NCX inhibition against arrhythmogenic Ca2+i rise in conditions when [Ca2+]i was augmented via activation of the late sodium current (INaL) or inhibition of the Na+/K+ pump. Experimental Approach Action potentials (APs) were recorded from canine papillary muscles and Purkinje fibres by microelectrodes. NCX current (INCX) was determined in ventricular cardiomyocytes utilizing the whole-cell patch clamp technique. Ca2+i transients (CaTs) were monitored with a Ca2+-sensitive fluorescent dye, Fluo-4. Key Results Enhanced INaL increased the Ca2+ load and AP duration (APD). SEA0400 and ORM10103 suppressed INCX and prevented/reversed the anemone toxin II (ATX-II)-induced [Ca2+]i rise without influencing APD, CaT or cell shortening, or affecting the ATX-II-induced increased APD. ORM10103 significantly decreased the number of strophanthidin-induced spontaneous diastolic Ca2+ release events; however, SEA0400 failed to restrict the veratridine-induced augmentation in Purkinje-ventricle APD dispersion. Conclusions and Implications Selective NCX inhibition – presumably by blocking revINCX (reverse mode NCX current) – is effective against arrhythmogenesis caused by [Na+]i-induced [Ca2+]i elevation, without influencing the AP waveform. Therefore, selective INCX inhibition, by significantly reducing the arrhythmogenic trigger activity caused by the perturbed Ca2+i handling, should be considered as a promising anti-arrhythmic therapeutic strategy. PMID:25073832

  17. Laser flash photolysis study on 9-phenylxanthenium tetrafluoroborate: Identification of new features due to the triplet state

    Indian Academy of Sciences (India)

    Sanghamitra Banerjee; Anunay Samanta

    2011-01-01

    Laser flash photolysis study on highly fluorescent and stable salt of 9-phenylxanthenium cation in neutral condition has been carried out for the first time. A new transient absorption band of this extensively studied system that perhaps remained buried under the fluorescence envelope and hitherto undetected has been identified and attributed to the triplet state of the system. This oxygen-insensitive triplet-triplet absorption band in the 480-600 nm range is expected to trigger new studies exploring the reactivity of the triplet state of this system, which has so far received very little attention.

  18. Dissecting galaxy triplets in the Sloan Digital Sky Survey Data Release 10: I. Stellar populations and emission line analysis

    Science.gov (United States)

    Costa-Duarte, M. V.; O'Mill, A. L.; Duplancic, F.; Sodré, L.; Lambas, D. G.

    2016-04-01

    We identify isolated galaxy triplets in a volume-limited sample from the Sloan Digital Sky Survey Data Release 10. Our final sample has 80 galaxy systems in the redshift range 0.04≤z≤0.1, brighter than Mr = -20.5 + 5log h70. Spectral synthesis results and WHAN and BPT diagnostic diagrams were employed to classify the galaxies in these systems as star-forming, active nuclei, or passive/retired. Our results suggest that the brightest galaxies drive the triplet evolution, as evidenced by the strong correlations between properties as mass assembly and mean stellar population age with triplet properties. Galaxies with intermediate luminosity or the faintest one within the triplet seem to play a secondary role. Moreover, the relation between age and stellar mass of galaxies is similar for these galaxies but different for the brightest galaxy in the system. Most of the triplet galaxies are passive or retired, according to the WHAN classification. Low mass triplets present different fractions of WHAN classes when compared to higher mass triplets. A census of WHAN class combinations shows the dominance of star-forming galaxies in low mass triplets while retired and passive galaxies prevail in high-mass systems. We argue that these results suggest that the local environment, through galaxy interactions driven by the brightest galaxy, is playing a major role in triplet evolution.

  19. Dissecting galaxy triplets in the Sloan Digital Sky Survey Data Release 10 - I. Stellar populations and emission line analysis

    Science.gov (United States)

    Costa-Duarte, M. V.; O'Mill, A. L.; Duplancic, F.; Sodré, L.; Lambas, D. G.

    2016-07-01

    We identify isolated galaxy triplets in a volume-limited sample from the Sloan Digital Sky Survey Data Release 10. Our final sample has 80 galaxy systems in the redshift range 0.04 ≤ z ≤ 0.1, brighter than Mr = -20.5 + 5 log h70. Spectral synthesis results and WHAN and BPT diagnostic diagrams were employed to classify the galaxies in these systems as star-forming, active nuclei, or passive/retired. Our results suggest that the brightest galaxies drive the triplet evolution, as evidenced by the strong correlations between properties as mass assembly and mean stellar population age with triplet properties. Galaxies with intermediate luminosity or the faintest one within the triplet seem to play a secondary role. Moreover, the relation between age and stellar mass of galaxies is similar for these galaxies but different for the brightest galaxy in the system. Most of the triplet galaxies are passive or retired, according to the WHAN classification. Low-mass triplets present different fractions of WHAN classes when compared to higher mass triplets. A census of WHAN class combinations shows the dominance of star-forming galaxies in low-mass triplets while retired and passive galaxies prevail in high-mass systems. We argue that these results suggest that the local environment, through galaxy interactions driven by the brightest galaxy, is playing a major role in triplet evolution.

  20. Matrix genetics, part 1: permutations of positions in triplets and symmetries of genetic matrices

    CERN Document Server

    Petoukhov, Sergey V

    2008-01-01

    The hidden connection between the degeneracy of the vertebrate mitochondria genetic code and the positional permutations inside genetic triplets is described. The Kronecker family of the genetic matrices is investigated, which is based on the genetic matrix [C A; U G], where C, A, U, G are the letters of the genetic alphabet. The natural system of binary numeration of genetic multiplets in the genetic matrices is proposed. The matrix [C A; U G] in the third Kronecker power is the (8*8)-matrix, which contains 64 triplets. When 64 triplets in this matrix are numbered in accordance with the natural system, the coincidence with the famous table of 64 hexagrams of the ancient Chinese book "I Ching" arises. It is significant that peculiarities of the degeneracy of the vertebrate mitochondria genetic code are reflected in the symmetrical black-and-white mosaic of this genetic (8*8)-matrix of 64 triplets. This matrix is reformed into a new mosaic matrix when internal positions in all triplets are permuted simultaneou...

  1. Triplet State Formation in Photovoltaic Blends of DPP-Type Copolymers and PC71BM

    KAUST Repository

    Ochsmann, Julian R.

    2015-04-29

    The exciton dynamics in pristine films of two structurally related low-bandgap diketopyrrolopyrrole (DPP)-based donor–acceptor copolymers and the photophysical processes in bulk heterojunction solar cells using DPP copolymer:PC71BM blends are investigated by broadband transient absorption (TA) pump-probe experiments covering the vis–near-infrared spectral and fs–μs dynamic range. The experiments reveal surprisingly short exciton lifetimes in the pristine poly­mer films in conjunction with fast triplet state formation. An in-depth analysis of the TA data by multivariate curve resolution analysis shows that in blends with fullerene as acceptor ultrafast exciton dissociation creates charge carriers, which then rapidly recombine on the sub-ns timescale. Furthermore, at the carrier densities created by pulsed laser excitation the charge carrier recombination leads to a substantial population of the polymer triplet state. In fact, virtually quantitative formation of triplet states is observed on the sub-ns timescale. However, the quantitative triplet formation on the sub-ns timescale is not in line with the power conversion efficiencies of devices indicating that triplet state formation is an intensity-dependent process in these blends and is reduced under solar illumination conditions, as free charge carriers can be extracted from the photoactive layer in devices.

  2. Triplet excited state energies and phosphorescence spectra of (bacterio)chlorophylls.

    Science.gov (United States)

    Hartzler, Daniel A; Niedzwiedzki, Dariusz M; Bryant, Donald A; Blankenship, Robert E; Pushkar, Yulia; Savikhin, Sergei

    2014-07-01

    (Bacterio)Chlorophyll ((B)Chl) molecules play a major role in photosynthetic light-harvesting proteins, and the knowledge of their triplet state energies is essential to understand the mechanisms of photodamage and photoprotection, as the triplet excitation energy of (B)Chl molecules can readily generate highly reactive singlet oxygen. The triplet state energies of 10 natural chlorophyll (Chl a, b, c2, d) and bacteriochlorophyll (BChl a, b, c, d, e, g) molecules and one bacteriopheophytin (BPheo g) have been directly determined via their phosphorescence spectra. Phosphorescence of four molecules (Chl c2, BChl e and g, BPheo g) was characterized for the first time. Additionally, the relative phosphorescence to fluorescence quantum yield for each molecule was determined. The measurements were performed at 77K using solvents providing a six-coordinate environment of the Mg(2+) ion, which allows direct comparison of these (B)Chls. Density functional calculations of the triplet state energies show good correlation with the experimentally determined energies. The correlation determined computationally was used to predict the triplet energies of three additional (B)Chl molecules: Chl c1, Chl f, and BChl f. PMID:24896677

  3. Preorganized Chromophores Facilitate Triplet Energy Migration, Annihilation and Upconverted Singlet Energy Collection.

    Science.gov (United States)

    Mahato, Prasenjit; Yanai, Nobuhiro; Sindoro, Melinda; Granick, Steve; Kimizuka, Nobuo

    2016-05-25

    Photon upconversion (UC) based on triplet-triplet annihilation (TTA) has the potential to enhance significantly photovoltaic and photocatalytic efficiencies by harnessing sub-bandgap photons, but the progress of this field is held back by the chemistry problem of how to preorganize multiple chromophores for efficient UC under weak solar irradiance. Recently, the first maximization of UC quantum yield at solar irradiance was achieved using fast triplet energy migration (TEM) in metal-organic frameworks (MOFs) with ordered acceptor arrays, but at the same time, a trade-off between fast TEM and high fluorescence efficiency was also found. Here, we provide a solution for this trade-off issue by developing a new strategy, triplet energy migration, annihilation and upconverted singlet energy collection (TEM-UPCON). The porous structure of acceptor-based MOF crystals allows triplet donor molecules to be accommodated without aggregation. The surface of donor-doped MOF nanocrystals is modified with highly fluorescent energy collectors through coordination bond formation. Thanks to the higher fluorescence quantum yield of surface-bound collectors than parent MOFs, the implementation of the energy collector greatly improves the total UC quantum yield. The UC quantum yield maximization behavior at ultralow excitation intensity was retained because the TTA events take place only in the MOF acceptors. The TEM-UPCON concept may be generalized to collectors with various functions and would lead to quantitative harvesting of upconverted energy, which is difficult to achieve in common molecular diffusion-based systems. PMID:27163784

  4. Cooperative singlet and triplet exciton transport in tetracene crystals visualized by ultrafast microscopy

    Science.gov (United States)

    Wan, Yan; Guo, Zhi; Zhu, Tong; Yan, Suxia; Johnson, Justin; Huang, Libai

    2015-10-01

    Singlet fission presents an attractive solution to overcome the Shockley-Queisser limit by generating two triplet excitons from one singlet exciton. However, although triplet excitons are long-lived, their transport occurs through a Dexter transfer, making them slower than singlet excitons, which travel by means of a Förster mechanism. A thorough understanding of the interplay between singlet fission and exciton transport is therefore necessary to assess the potential and challenges of singlet-fission utilization. Here, we report a direct visualization of exciton transport in single tetracene crystals using transient absorption microscopy with 200 fs time resolution and 50 nm spatial precision. These measurements reveal a new singlet-mediated transport mechanism for triplets, which leads to an enhancement in effective triplet exciton diffusion of more than one order of magnitude on picosecond to nanosecond timescales. These results establish that there are optimal energetics of singlet and triplet excitons that benefit both singlet fission and exciton diffusion.

  5. Energy-donor phosphorescence quenching study of triplet–triplet energy transfer between UV absorbers

    International Nuclear Information System (INIS)

    The intermolecular triplet–triplet energy transfer from a photounstable UV-A absorber, 4-tert-butyl-4′-methoxydibenzoylmethane (BMDBM), to UV-B absorbers, 2-ethylhexyl 4-methoxycinnamate (octyl methoxycinnamate, OMC), octocrylene (OCR) and dioctyl 4-methoxybenzylidenemalonate (DOMBM) has been observed using a 355 nm laser excitation in rigid solutions at 77 K. The decay curves of the energy-donor phosphorescence in the presence of the UV-B absorbers deviate from the exponential decay at the initial stage of the decay. The Stern–Volmer formulation is not valid in rigid solutions because molecular diffusion is impossible. The experimental results indicate that the rate constant of triplet–triplet energy transfer from BMDBM to the UV-B absorbers, kT–T, decreases in the following order: kT–T (BMDBM–DOMBM)>kT–T (BMDBM–OMC)≥kT–T (BMDBM–OCR). The presence of DOMBM enhances the photostability of the widely used combination of UV-A and UV-B absorbers, BMDBM and OCR. The effects of the triplet–triplet energy transfer on the photostability of BMDBM are discussed. - Highlights: • The intermolecular triplet–triplet energy transfer between UV absorbers was observed. • The phosphorescence decay deviates from exponential at the initial stage of decay. • The effects of triplet–triplet energy transfer on the photostability are discussed

  6. Energy-donor phosphorescence quenching study of triplet–triplet energy transfer between UV absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Azusa; Nakabai, Yuya [Department of Chemistry, Graduate School of Engineering, Yokohama National University, Tokiwadai, Hodogaya-ku, Yokohama 240-8501 (Japan); Oguchi-Fujiyama, Nozomi; Miyazawa, Kazuyuki [Shiseido Research Center, Hayabuchi, Tsuzuki-ku, Yokohama 224-8558 (Japan); Yagi, Mikio, E-mail: yagimiki@ynu.ac.jp [Department of Chemistry, Graduate School of Engineering, Yokohama National University, Tokiwadai, Hodogaya-ku, Yokohama 240-8501 (Japan)

    2015-10-15

    The intermolecular triplet–triplet energy transfer from a photounstable UV-A absorber, 4-tert-butyl-4′-methoxydibenzoylmethane (BMDBM), to UV-B absorbers, 2-ethylhexyl 4-methoxycinnamate (octyl methoxycinnamate, OMC), octocrylene (OCR) and dioctyl 4-methoxybenzylidenemalonate (DOMBM) has been observed using a 355 nm laser excitation in rigid solutions at 77 K. The decay curves of the energy-donor phosphorescence in the presence of the UV-B absorbers deviate from the exponential decay at the initial stage of the decay. The Stern–Volmer formulation is not valid in rigid solutions because molecular diffusion is impossible. The experimental results indicate that the rate constant of triplet–triplet energy transfer from BMDBM to the UV-B absorbers, k{sub T–T}, decreases in the following order: k{sub T–T} (BMDBM–DOMBM)>k{sub T–T} (BMDBM–OMC)≥k{sub T–T} (BMDBM–OCR). The presence of DOMBM enhances the photostability of the widely used combination of UV-A and UV-B absorbers, BMDBM and OCR. The effects of the triplet–triplet energy transfer on the photostability of BMDBM are discussed. - Highlights: • The intermolecular triplet–triplet energy transfer between UV absorbers was observed. • The phosphorescence decay deviates from exponential at the initial stage of decay. • The effects of triplet–triplet energy transfer on the photostability are discussed.

  7. Theoretical study of the intensity of chemically induce dynamic electron polarization of radical-triplet pairs

    Institute of Scientific and Technical Information of China (English)

    XU Xin-sheng; ZHANG Xian-yi; ZHANG Wei-jun; CUI Zhi-feng; LU Tong-xing

    2003-01-01

    Considering the interaction between excited triplet molecule and doublet radical, based on the second-order perturbation theory and the motion equation of density matrix, the polarization intensity of RTPM were theoretically calculated with the overpopulated doublet spin states and quartet spin states of radical-triplet pairs as initial conditions respectively. The results of calculation indicate that the net emissive polarization and the net absorptive polarization on the radical result from the zero-field-splitting (zfs) and the multiplet A/E and E/A polarization result from hyperfine (hf) interactions of the triplet molecule. The hyperfine related A+A/E or E+E/A CIDEP on the radical were the overpopulation of the net absorptive or emissive polarization and multiplet A/E or E/A polarization..

  8. Dark matter and a suppression mechanism for neutrino masses in the Higgs triplet model

    CERN Document Server

    Kanemura, Shinya

    2012-01-01

    We extend the Higgs triplet model so as to include dark matter candidates and a simple suppression mechanism for the vacuum expectation value (v_Delta) of the triplet scalar field. The smallness of neutrino masses can be naturally explained with the suppressed value of v_Delta even when the triplet fields are at the TeV scale. The Higgs sector is extended by introducing Z_2-odd scalars (an SU(2)_L doublet eta and a real singlet s_2^0) in addition to a Z_2-even complex singlet scalar s_1^0 whose vacuum expectation value violates the lepton number conservation by a unit. In our model, v_Delta is generated by the one-loop diagram to which Z_2-odd particles contribute. The lightest Z_2-odd scalar boson can be a candidate for the dark matter. We briefly discuss a characteristic signal of our model at the LHC.

  9. Conditions for describing triplet states in reduced density matrix functional theory

    CERN Document Server

    Theophilou, Iris; Helbig, Nicole

    2016-01-01

    We consider necessary conditions for the one body-reduced density matrix (1RDM) to correspond to a triplet wave-function of a two electron system. The conditions concern the occupation numbers and are different for the high spin projections, $S_z=\\pm 1$, and the $S_z=0$ projection. We employ these conditions in reduced density matrix functional theory calculations for the triplet excitations of two electron systems. In addition, we propose that these conditions can be used in the calculation of triplet states of systems with more than two electrons by restricting the active space and assess this procedure in calculations for a few atomic and molecular systems. We show that the quality of the optimal 1RDMs improves by applying the conditions in all the cases we studied.

  10. Inelastic collisions of ultracold triplet Rb$_\\textbf{2}$ molecules in the rovibrational ground state

    CERN Document Server

    Drews, Björn; Jachymski, Krzysztof; Idziaszek, Zbigniew; Denschlag, Johannes Hecker

    2016-01-01

    Exploring inelastic and reactive collisions on the quantum level is a main goal of the developing field of ultracold chemistry. We present first experimental studies of inelastic collisions of metastable ultracold triplet molecules in the vibrational ground state. The measurements are performed with nonpolar Rb$_2$ dimers which are prepared in precisely-defined quantum states and trapped in an array of quasi-1D potential tubes. We investigate collisions of molecules in the lowest triplet energy level where any inelastic process requires a relaxation to the singlet state. These are compared to two sets of collision experiments, carried out either with triplet molecules that have two quanta of rotational angular momentum or with vibrationally highly excited Feshbach molecules. We find no evidence for suppression of the inelastic collisions due to the necessary spin-flip, shedding light on this so far unsettled issue. For each of the molecular states studied here, we extract the decay rate constant and compare t...

  11. Monochorionic triamniotic triplets following conventional in vitro fertilization and blastocyst transfer.

    Science.gov (United States)

    Gurunath, Sumana; Makam, Adinarayana; Vinekar, Sriprada; Biliangady, Reeta H

    2015-01-01

    Multiple pregnancy in in vitro fertilization (IVF) is on the decline with a reduction in number of embryos transferred. But the risk of monozygotic splitting persists. The risk of monozygotic twinning in women undergoing IVF is reported to be twice that of natural conception, and monochorionic triplets are even rarer at 100 times more than natural conception. We report a case of monochorionic triamniotic (MCTA) triplets following conventional IVF and blastocyst transfer without zona manipulation. This report highlights the possibility of zygotic splitting in IVF in young couples with no family history, in centers with good experience with blastocyst transfer. MCTA triplets carry a high risk of perinatal mortality and morbidity and need multidisciplinary care. Prevention and prediction of zygotic splitting ought to be realized with better reporting and identification of possible risk factors. PMID:25838751

  12. Monochorionic triamniotic triplets following conventional in vitro fertilization and blastocyst transfer

    Directory of Open Access Journals (Sweden)

    Sumana Gurunath

    2015-01-01

    Full Text Available Multiple pregnancy in in vitro fertilization (IVF is on the decline with a reduction in number of embryos transferred. But the risk of monozygotic splitting persists. The risk of monozygotic twinning in women undergoing IVF is reported to be twice that of natural conception, and monochorionic triplets are even rarer at 100 times more than natural conception. We report a case of monochorionic triamniotic (MCTA triplets following conventional IVF and blastocyst transfer without zona manipulation. This report highlights the possibility of zygotic splitting in IVF in young couples with no family history, in centers with good experience with blastocyst transfer. MCTA triplets carry a high risk of perinatal mortality and morbidity and need multidisciplinary care. Prevention and prediction of zygotic splitting ought to be realized with better reporting and identification of possible risk factors.

  13. Direct generation of photon triplets using cascaded photon-pair sources

    CERN Document Server

    Hübel, H; Fedrizzi, A; Ramelow, S; Resch, K J; Jennewein, T

    2010-01-01

    Non-classical states of light, such as entangled photon pairs and number states, are essential for fundamental tests of quantum mechanics and optical quantum technologies. The most widespread technique for creating these quantum resources is the spontaneous parametric down-conversion (SPDC) of laser light into photon pairs. Conservation of energy and momentum in this process, known as phase-matching, gives rise to strong correlations which are used to produce two-photon entanglement in various degrees of freedom. It has been a longstanding goal of the quantum optics community to realise a source that can produce analogous correlations in photon triplets, but of the many approaches considered, none have been technically feasible. In this paper we report the observation of photon triplets generated by cascaded down-conversion. Here each triplet originates from a single pump photon, and therefore quantum correlations will extend over all three photons in a way not achievable with independently created photon pai...

  14. Conditions for Describing Triplet States in Reduced Density Matrix Functional Theory.

    Science.gov (United States)

    Theophilou, Iris; Lathiotakis, Nektarios N; Helbig, Nicole

    2016-06-14

    We consider necessary conditions for the one-body reduced density matrix (1RDM) to correspond to a triplet wave function of a two-electron system. The conditions concern the occupation numbers and are different for the high spin projections, Sz = ±1, and the Sz = 0 projection. Hence, they can be used to test if an approximate 1RDM functional yields the same energies for both projections. We employ these conditions in reduced density matrix functional theory calculations for the triplet excitations of two-electron systems. In addition, we propose that these conditions can be used in the calculation of triplet states of systems with more than two electrons by restricting the active space. We assess this procedure in calculations for a few atomic and molecular systems. We show that the quality of the optimal 1RDMs improves by applying the conditions in all the cases we studied. PMID:27171683

  15. Neutrino masses, anomalous U(1) gauge symmetry and doublet-triplet splitting

    International Nuclear Information System (INIS)

    We propose an attractive scenario of grand unified theories in which doublet-triplet splitting is naturally realized in SO(10) unification using the Dimopoulos-Wilczek mechanism. The anomalous U(1)A gauge symmetry plays an essential role in the double-triplet splitting mechanism. It is interesting that the anomalous U(1)A charges determine the unification scale and mass spectrum of additional particles, as well as the order of the Yukawa couplings of quarks and leptons. For the neutrino sector, bi-maximal mixing angles are naturally obtained, and proton decay via dimension 5 operators is suppressed. It is suggestive that the anomalous U(1)A gauge symmetry motivated by superstring theory effectively solves the two biggest problems in grand unified theories, the fermion mass hierarchy problem and doublet-triplet splitting problem. (author)

  16. A Memristive Model Compatible with Triplet Rule for Spike-Timing-Dependent-Plasticity

    CERN Document Server

    Cai, Weiran; Ellinger, Frank

    2011-01-01

    In this paper, we propose an extended version of the memristive STDP model, which is one of the most important and exciting recent discoveries in neuromorphic engineering. The proposed model aims to claim compatibility with another importent STDP rule beyond the pair-based rule, known as the triplet STDP rule. This is an extension of the asynchronous memristive model of Linares-Barranco, et al., capable of explaining the pair-based rule based on the analogy of the synapse to the memristor. The proposed new model is compatible with both the pair-baed and triplet-based rule, by assuming a mechanism of variable thresholds adapting to synaptic potentiation and depression. The dynamical process is governed by ordinary differential equations. The model is an expression of Froemke's principle of suppression for triplet rules and reveals a similar time dependence with that in the suppression STDP model.

  17. Triplet excited state spectra and dynamics of carotenoids from the thermophilic purple photosynthetic bacterium Thermochromatium tepidum

    Energy Technology Data Exchange (ETDEWEB)

    Niedzwiedzki, Dariusz; Kobayashi, Masayuki; Blankenship, R. E.

    2011-01-13

    Light-harvesting complex 2 from the anoxygenic phototrophic purple bacterium Thermochromatium tepidum was purified and studied by steady-state absorption, fluorescence and flash photolysis spectroscopy. Steady-state absorption and fluorescence measurements show that carotenoids play a negligible role as supportive energy donors and transfer excitation to bacteriochlorophyll-a with low energy transfer efficiency of ~30%. HPLC analysis determined that the dominant carotenoids in the complex are rhodopin and spirilloxanthin. Carotenoid excited triplet state formation upon direct (carotenoid) or indirect (bacteriochlorophyll-a Q{sub x} band) excitation shows that carotenoid triplets are mostly localized on spirilloxanthin. In addition, no triplet excitation transfer between carotenoids was observed. Such specific carotenoid composition and spectroscopic results strongly suggest that this organism optimized carotenoid composition in the light-harvesting complex 2 in order to maximize photoprotective capabilities of carotenoids but subsequently drastically suppressed their supporting role in light-harvesting process.

  18. Solid state photon upconversion utilizing thermally activated delayed fluorescence molecules as triplet sensitizer

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Tony C.; Congreve, Daniel N.; Baldo, Marc A., E-mail: baldo@mit.edu [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2015-07-20

    The ability to upconvert light is useful for a range of applications, from biological imaging to solar cells. But modern technologies have struggled to upconvert incoherent incident light at low intensities. Here, we report solid state photon upconversion employing triplet-triplet exciton annihilation in an organic semiconductor, sensitized by a thermally activated-delayed fluorescence (TADF) dye. Compared to conventional phosphorescent sensitizers, the TADF dye maximizes the wavelength shift in upconversion due to its small singlet-triplet splitting. The efficiency of energy transfer from the TADF dye is 9.1%, and the conversion yield of sensitizer exciton pairs to singlet excitons in the annihilator is 1.1%. Our results demonstrate upconversion in solid state geometries and with non-heavy metal-based sensitizer materials.

  19. Formation of the O I resonance triplet and intercombination doublet in the solar chromosphere

    International Nuclear Information System (INIS)

    Spectrum synthesis calculations are presented for the O I resonance triplet at 1304 A and the intercombination doublet at 1358 A for the solar atmosphere of Vernazza, Avrett, and Loeser and several variants, allowing for triplet fluorescence by the Lyβ emission of H I. Profiles, synthesized from a seven-level plus continuum O I atom are compared to observations taken with the high-resolution spectrometer on OSO 8, calibrated with the irradiance measurements of Heroux and Higgins. We find tha the O I triplet emission is dominated by the Lyβ fluorescence and that the agreement between observations and profiles computed with current chromospheric models is much improved over earlier studies

  20. Modulating the generation of long-lived charge separated states exclusively from the triplet excited states in palladium porphyrin-fullerene conjugates

    Science.gov (United States)

    O. Obondi, Christopher; Lim, Gary N.; Churchill, Brittani; Poddutoori, Prashanth K.; van der Est, Art; D'Souza, Francis

    2016-04-01

    This study demonstrates molecular engineering of a series of donor-acceptor systems to allow control of the lifetime and initial spin multiplicity of the charge-separated state. By tuning the rate of intersystem crossing (ISC) and the donor-acceptor distance, electron transfer can be made to occur exclusively from the triplet excited state of the electron donor resulting in long-lived charge separation. To achieve this, three new palladium porphyrin-fullerene donor-acceptor systems were synthesized. The heavy Pd atom enhances the rate of ISC in the porphyrin and the rates of electron and energy transfer are modulated by varying the redox potential of the porphyrin and the porphyrin-fullerene distance. In the case of the meso-tris(tolyl)porphyrinato palladium(ii)-fulleropyrrolidine, the donor-acceptor distance is relatively long (13.1 Å) and the driving force for electron transfer is low. As a result, excitation of the porphyrin leads to rapid ISC followed by triplet-triplet energy transfer to fullerene. When the fullerene is bound directly to the porphyrin shortening the donor-acceptor distance to 2.6 Å electron transfer from the singlet excited palladium porphyrin leading to the generation of a short-lived charge separated state is the main process. Finally, when the palladium porphyrin is substituted with three electron rich triphenylamine entities, the lower oxidation potential of the porphyrin and appropriate donor-acceptor distance (~13 Å), lead to electron transfer exclusively from the triplet excited state of palladium porphyrin with high quantum yield. The results show that when electron transfer occurs from the triplet state, its increased lifetime allows the distance between the donor and acceptor to be increased which results in a longer lifetime for the charge separated state.This study demonstrates molecular engineering of a series of donor-acceptor systems to allow control of the lifetime and initial spin multiplicity of the charge-separated state

  1. iTriplet, a rule-based nucleic acid sequence motif finder

    Directory of Open Access Journals (Sweden)

    Gunderson Samuel I

    2009-10-01

    Full Text Available Abstract Background With the advent of high throughput sequencing techniques, large amounts of sequencing data are readily available for analysis. Natural biological signals are intrinsically highly variable making their complete identification a computationally challenging problem. Many attempts in using statistical or combinatorial approaches have been made with great success in the past. However, identifying highly degenerate and long (>20 nucleotides motifs still remains an unmet challenge as high degeneracy will diminish statistical significance of biological signals and increasing motif size will cause combinatorial explosion. In this report, we present a novel rule-based method that is focused on finding degenerate and long motifs. Our proposed method, named iTriplet, avoids costly enumeration present in existing combinatorial methods and is amenable to parallel processing. Results We have conducted a comprehensive assessment on the performance and sensitivity-specificity of iTriplet in analyzing artificial and real biological sequences in various genomic regions. The results show that iTriplet is able to solve challenging cases. Furthermore we have confirmed the utility of iTriplet by showing it accurately predicts polyA-site-related motifs using a dual Luciferase reporter assay. Conclusion iTriplet is a novel rule-based combinatorial or enumerative motif finding method that is able to process highly degenerate and long motifs that have resisted analysis by other methods. In addition, iTriplet is distinguished from other methods of the same family by its parallelizability, which allows it to leverage the power of today's readily available high-performance computing systems.

  2. Charge Transfer and Triplet States in High Efficiency OPV Materials and Devices

    Science.gov (United States)

    Dyakonov, Vladimir

    2013-03-01

    The advantage of using polymers and molecules in electronic devices, such as light-emitting diodes (LED), field-effect transistors (FET) and, more recently, solar cells (SC) is justified by the unique combination of high device performance and processing of the semiconductors used. Power conversion efficiency of nanostructured polymer SC is in the range of 10% on lab scale, making them ready for up-scaling. Efficient charge carrier generation and recombination in SC are strongly related to dissociation of the primary singlet excitons. The dissociation (or charge transfer) process should be very efficient in photovoltaics. The mechanisms governing charge carrier generation, recombination and transport in SC based on the so-called bulk-heterojunctions, i.e. blends of two or more semiconductors with different electron affinities, appear to be very complex, as they imply the presence of the intermediate excited states, neutral and charged ones. Charge transfer states, or polaron pairs, are the intermediate states between free electrons/holes and strongly bound excitons. Interestingly, the mostly efficient OLEDs to date are based on the so-called triplet emitters, which utilize the triplet-triplet annihilation process. In SC, recent investigations indicated that on illumination of the device active layer, not only mobile charges but also triplet states were formed. With respect to triplets, it is unclear how these excited states are generated, via inter-system crossing or via back transfer of the electron from acceptor to donor. Triplet formation may be considered as charge carrier loss channel; however, the fusion of two triplets may lead to a formation of singlet excitons instead. In such case, a generation of charges by utilizing of the so far unused photons will be possible. The fundamental understanding of the processes involving the charge transfer and triplet states and their relation to nanoscale morphology and/or energetics of blends is essential for the

  3. Preferential Nucleosome Assembly at DNA Triplet Repeats from the Myotonic Dystrophy Gene

    Science.gov (United States)

    Wang, Yuh-Hwa; Amirhaeri, Sorour; Kang, Seongman; Wells, Robert D.; Griffith, Jack D.

    1994-07-01

    The expansion of CTG repeats in DNA occurs in or near genes involved in several human diseases, including myotonic dystrophy and Huntington's disease. Nucleosomes, the basic structural element of chromosomes, consist of 146 base pairs of DNA coiled about an octamer of histone proteins and mediate general transcriptional repression. Electron microscopy was used to examine in vitro the nucleosome assembly of DNA containing repeating CTG triplets. The efficiency of nucleosome formation increased with expanded triplet blocks, suggesting that such blocks may repress transcription through the creation of stable nucleosomes.

  4. Detecting luminescence from triplet states of organic semiconductors at room temperatures using delayed electroluminescence spectroscopy

    Science.gov (United States)

    Wang, Qi; Aziz, Hany

    2014-08-01

    We demonstrate a unique approach for detecting luminescence from triplet states of organic materials in the solid state at room temperatures. The technique is based on measuring delayed electroluminescence from the material. The approach overcomes limitations of conventional spectroscopic techniques, such as the need for cooling to cryogenic temperatures, and works for a wide range of organic materials. The underlying mechanisms behind observing materials phosphorescence using this technique are studied. The results show that using a low concentration of the target material doped in a host material and a large energy differences between triplet states of target and host materials are necessary for obtaining efficient phosphorescence at room temperatures.

  5. Energy deposition studies for the High-Luminosity Large Hadron Collider inner triplet magnets

    CERN Document Server

    Mokhov, N V; Tropin, I S; Cerutti, F; Esposito, L S; Lechner, A

    2015-01-01

    A detailed model of the High Luminosity LHC inner triplet region with new large-aperture Nb3Sn magnets, field maps, corrector packages, and segmented tungsten inner absorbers was built and implemented into the FLUKA and MARS15 codes. In the optimized configuration, the peak power density averaged over the magnet inner cable width is safely below the quench limit. For the integrated luminosity of 3000 fb-1, the peak dose in the innermost magnet insulator ranges from 20 to 35 MGy. Dynamic heat loads to the triplet magnet cold mass are calculated to evaluate the cryogenic capability. In general, FLUKA and MARS results are in a very good agreement.

  6. Energy Deposition Studies for the Hi-Lumi LHC Inner Triplet Magnets

    CERN Document Server

    Mokhov, N V; Striganov, S I; Tropin, I S; Cerutti, F; Esposito, L; Lechner, A

    2015-01-01

    A detailed model of the High Luminosity LHC inner triplet region with new large-aperture Nb3Sn magnets, field maps, corrector packages, and segmented tungsten inner absorbers was built and implemented into the FLUKA and MARS15 codes. In the optimized configuration, the peak power density averaged over the magnet inner cable width is safely below the quench limit. For the integrated luminosity of 3000 fb -1, the peak dose in the innermost magnet insulator ranges from 20 to 35 MGy. Dynamic heat loads to the triplet magnet cold mass are calculated to evaluate the cryogenic capability. In general, FLUKA and MARS results are in a very good agreement.

  7. Characterization of the Triplet State of Tris(8-hydroxyquinoline)aluminium(III) in Benzene Solution

    OpenAIRE

    Burrows, Hugh D.; Fernandes, Mariana; Melo, J. Seixas de; Monkman, Andrew P.; NAVARATNAM, SUPPIAH

    2003-01-01

    The lowest triplet state of tris(8-hydroxyquinoline)aluminium(III) (Alq3) has been prepared by pulse radiolysis/energy transfer from appropriate donors in benzene solutions and has an absorption maximum around 510 nm with a lifetime of about 50 μs. It is quenched by molecular oxygen, leading to singlet oxygen formation. From flash photolysis and singlet oxygen formation measurements, a quantum yield of triplet formation of 0.24 was determined for direct photolysis of the complex. A value of 2...

  8. Spectrally tunable mollow triplet emission from a coherently excited quantum dot in a microcavity

    DEFF Research Database (Denmark)

    Ulrich, Sven M.; Ates, Serkan; Reitzenstein, Stephan;

    2010-01-01

    Resonance fluorescence of excitonic s-shell emission from a coherently pumped single InGaAs/GaAs quantum dot inside a micropillar cavity has been investigated in dependence on optical pump power and laser detuning, respectively. For strong purely resonant excitation, Mollow triplet spectra with l...... large Rabi splittings of j~­j » 60¹eV have been observed. Laser detuning-dependent series revealed the pronounced asymmetry of the emission triplet as predicted by theory. From our data, an electrical dipole moment of ¹ » 17:8§0:5 Debye could be derived for the excitonic state....

  9. Toward Singlet-Triplet Bistable Nonalternant Kekulé Hydrocarbons: Azulene-to-Naphthalene Rearrangement.

    Science.gov (United States)

    Das, Soumyajit; Wu, Jishan

    2015-12-01

    Recent developments of open-shell singlet diradicaloids motivated the search for stable singlet-triplet bistable nonalternant polycyclic hydrocarbons. During the synthesis of this type of molecule, such as the dibenzo-cyclohepta[def]fluorene 3, an unexpected azulene-to-naphthalene rearrangement was observed at room temperature, which resulted in new nonalternant hydrocarbons 8a/8b with a closed-shell singlet ground state. These studies provided insight into the unique chemistry of azulene and challenges for the synthesis of singlet-triplet bistable polycyclic hydrocarbons. PMID:26569547

  10. Multiphoton ionization through the triplet states of Mg by linearly and circularly polarized laser pulses

    CERN Document Server

    Buica, Gabriela; 10.1103/PhysRevA.79.013419

    2013-01-01

    We theoretically study multiphoton ionization through the triplet states of Mg by linearly polarized (LP) and circularly polarized (CP) fs laser pulses. After the construction of the atomic basis using the frozen-core Hartree-Fock potential (FCHFP) as well as the model potential (MP) approaches for both singlet and triplet series which show rather good agreements with the existing data in terms of state energies and dipole matrix elements, we solve time-dependent Schr\\"{o}dinger equations with $3s3p$ $^{3}P_{1}$ as an initial state, and calculate the total ionization yield and photoelectron energy spectra (PES).

  11. Signatures of Higgs-Triplet representations at TeV-e+e- colliders

    International Nuclear Information System (INIS)

    The authors investigate the potential of future TeV linear e+e- colliders to observe singly-charged Higgs bosons (H±) via the coupling H±W-+Z, which would signal the existence of exotic Higgs representations. In the context of a Higgs-triplet model compatible with the electroweak oblique parameters, they estimate the cross section for producing charged Higgs-triplet bosons that couple predominantly to W and Z bosons in 0.5-2 TeV-e+e- colliders. The principal backgrounds are evaluated and the viability of the signal is discussed and illustrated

  12. Triplet supercurrent due to spin-active zones in a Josephson junction

    Science.gov (United States)

    Linder, Jacob; Sudbø, Asle

    2010-07-01

    Motivated by a recent experiment evidencing triplet superconductivity in a ferromagnetic Josephson junction with a Cu2MnAl -Heusler barrier, we construct a theoretical model accounting for this observation. The key ingredients in our model which generate the triplet supercurrent are spin-active zones, characterized by an effective canted interface magnetic moment. Using a numerical solution of the quasiclassical equations of superconductivity with spin-active boundary conditions, we find qualitatively very good agreement with the experimentally observed supercurrent. Further experimental implications of the spin-active zones are discussed.

  13. Constraining Inert Triplet dark matter by the LHC and FermiLAT

    International Nuclear Information System (INIS)

    We study collider phenomenology of inert triplet scalar dark matter at the LHC. We discuss possible decay of Higgs boson to dark matter candidate and apply current experimental data for invisible Higgs decay and Rγγ to constrain parameter space of our model. We also investigate constraints on dark matter coming from forthcoming measurement, RZγ and mono-Higgs production. We analytically calculate the annihilation cross section of dark matter candidate into 2γ and Zγ and then use FermiLAT data to put constraints on parameter space of Inert Triplet Model. We found that this limit can be stronger than the constraints provided by LUX experiment for low mass DM

  14. Inhibition of endogenous heat shock protein 70 attenuates inducible nitric oxide synthase induction via disruption of heat shock protein 70/Na(+) /H(+) exchanger 1-Ca(2+) -calcium-calmodulin-dependent protein kinase II/transforming growth factor β-activated kinase 1-nuclear factor-κB signals in BV-2 microglia.

    Science.gov (United States)

    Huang, Chao; Lu, Xu; Wang, Jia; Tong, Lijuan; Jiang, Bo; Zhang, Wei

    2015-08-01

    Inducible nitric oxide synthase (iNOS) critically contributes to inflammation and host defense. The inhibition of heat shock protein 70 (Hsp70) prevents iNOS induction in lipopolysaccharide (LPS)-stimulated macrophages. However, the role and mechanism of endogenous Hsp70 in iNOS induction in microglia remains unclear. This study addresses this issue in BV-2 microglia, showing that Hsp70 inhibition or knockdown prevents LPS-induced iNOS protein expression and nitric oxide production. Real-time PCR experiments showed that LPS-induced iNOS mRNA transcription was blocked by Hsp70 inhibition. Further studies revealed that the inhibition of Hsp70 attenuated LPS-stimulated nuclear translocation and phosphorylation of nuclear factor (NF)-κB as well as the degradation of inhibitor of κB (IκB)-α and phosphorylation of IκB kinase β (IKKβ). This prevention effect of Hsp70 inhibition on IKKβ-NF-κB activation was found to be dependent on the Ca(2+) /calcium-calmodulin-dependent protein kinase II (CaMKII)/transforming growth factor β-activated kinase 1 (TAK1) signals based on the following observations: 1) chelation of intracellular Ca(2+) or inhibition of CaMKII reduced LPS-induced increases in TAK1 phosphorylation and 2) Hsp70 inhibition reduced LPS-induced increases in CaMKII/TAK1 phosphorylation, intracellular pH value, [Ca(2+) ]i , and CaMKII/TAK1 association. Mechanistic studies showed that Hsp70 inhibition disrupted the association between Hsp70 and Na(+) /H(+) exchanger 1 (NHE1), which is an important exchanger responsible for Ca(2+) influx in LPS-stimulated cells. These studies demonstrate that the inhibition of endogenous Hsp70 attenuates the induction of iNOS, which likely occurs through the disruption of NHE1/Hsp70-Ca(2+) -CaMKII/TAK1-NF-κB signals in BV-2 microglia, providing further insight into the functions of Hsp70 in the CNS. PMID:25691123

  15. π-Conjugated Organometallic Isoindigo Oligomer and Polymer Chromophores: Singlet and Triplet Excited State Dynamics and Application in Polymer Solar Cells.

    Science.gov (United States)

    Goswami, Subhadip; Gish, Melissa K; Wang, Jiliang; Winkel, Russell W; Papanikolas, John M; Schanze, Kirk S

    2015-12-01

    An isoindigo based π-conjugated oligomer and polymer that contain cyclometalated platinum(II) "auxochrome" units were subjected to photophysical characterization, and application of the polymer in bulk heterojunction polymer solar cells with PCBM acceptor was examined. The objective of the study was to explore the effect of the heavy metal centers on the excited state properties, in particular, intersystem crossing to a triplet (exciton) state, and further how this would influence the performance of the organometallic polymer in solar cells. The materials were characterized by electrochemistry, ground state absorption, emission, and picosecond-nanosecond transient absorption spectroscopy. Electrochemical measurements indicate that the cyclometalated units have a significant impact on the HOMO energy level of the chromophores, but little effect on the LUMO, which is consistent with localization of the LUMO on the isoindigo acceptor unit. Picosecond-nanosecond transient absorption spectroscopy reveals a transient with ∼100 ns lifetime that is assigned to a triplet excited state that is produced by intersystem crossing from a singlet state on a time scale of ∼130 ps. This is the first time that a triplet state has been observed for isoindigo π-conjugated chromophores. The performance of the polymer in bulk heterojunction solar cells was explored with PC61BM as an acceptor. The performance of the cells was optimum at a relatively high PCBM loading (1:6, polymer:PCBM), but the overall efficiency was relatively low with power conversion efficiency (PCE) of 0.22%. Atomic force microscopy of blend films reveals that the length scale of the phase separation decreases with increasing PCBM content, suggesting a reason for the increase in PCE with acceptor loading. Energetic considerations show that the triplet state in the polymer is too low in energy to undergo charge separation with PCBM. Further, due to the relatively low LUMO energy of the polymer, charge transfer

  16. Monochorionic-triamniotic triplet pregnancy after intracytoplasmic sperm injection, assisted hatching, and two-embryo transfer: first reported case following IVF

    Directory of Open Access Journals (Sweden)

    Eller Daniel P

    2003-08-01

    Full Text Available Abstract Background We present a case of monochorionic-triamniotic pregnancy that developed after embryo transfer following in vitro fertilization (IVF. Methods After controlled ovarian hyperstimulation and transvaginal retrieval of 22 metaphase II oocytes, fertilization was accomplished with intracytoplasmic sperm injection (ICSI. Assisted embryo hatching was performed, and two embryos were transferred in utero. One non-transferred blastocyst was cryopreserved. Results Fourteen days post-transfer, serum hCG level was 423 mIU/ml and subsequent transvaginal ultrasound revealed a single intrauterine gestational sac with three separate amnion compartments. Three distinct foci of cardiac motion were detected and the diagnosis was revised to monochorionic-triamniotic triplet pregnancy. Antenatal management included cerclage placement at 19 weeks gestation and hospital admission at 28 weeks gestation due to mild preeclampsia. Three viable female infants were delivered via cesarean at 30 5/7 weeks gestation. Conclusions The incidence of triplet delivery in humans is approximately 1:6400, and such pregnancies are classified as high-risk for reasons described in this report. We also outline an obstetric management strategy designed to optimize outcomes. The roles of IVF, ICSI, assisted embryo hatching and associated laboratory culture conditions on the subsequent development of monozygotic/monochorionic pregnancy remain controversial. As demonstrated here, even when two-embryo transfer is employed after IVF the statistical probability of monozygotic multiple gestation cannot be reduced to zero. We encourage discussion of this possibility during informed consent for the advanced reproductive technologies.

  17. Studies of energy transfer processes in triplet states using optically detected magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Lewellyn, M.T.

    1977-06-01

    The techniques of both continuous wave and pulsed-coherent optically detected magnetic resonance spectroscopy are used to study energy transfer processes in the lowest triplet states of two aromatic molecular crystals (1,2,4,5-tetrachlorobenzene and pyrimidine). Of particular interest are the effects of crystal dimensionality and isotopic trap states on the efficiency of the transfer process in these systems.

  18. Observation of the lowest triplet state in silane by electron energy loss spectroscopy

    International Nuclear Information System (INIS)

    The electron energy loss spetra of silane was recorded at several impact energies and angles. It is concluded that the lowest triplet state of silane is formed from configuration mixing of the 4s Rydberg state with a valence state of the same symmetry

  19. Tri-P-LETS: Changing the Face of High School Computer Science

    Science.gov (United States)

    Sherrell, Linda; Malasri, Kriangsiri; Mills, David; Thomas, Allen; Greer, James

    2012-01-01

    From 2004-2007, the University of Memphis carried out the NSF-funded Tri-P-LETS (Three P Learning Environment for Teachers and Students) project to improve local high-school computer science curricula. The project reached a total of 58 classrooms in eleven high schools emphasizing problem solving skills, programming concepts as opposed to syntax,…

  20. Long-range spin-triplet proximity effect in Josephson junctions with multilayered ferromagnets

    International Nuclear Information System (INIS)

    We study theoretically the Josephson effect and pairing correlations in planar SF1F2S junctions that consist of conventional superconductors (S) connected through two metallic monodomain ferromagnets (F1 and F2) with transparent interfaces. We solve self-consistently the Eilenberger equations for arbitrary orientation of in-plane magnetizations in the clean limit and for moderate disorder in ferromagnets. Both singlet and triplet pair amplitudes and the Josephson current-phase relations are calculated numerically. It is shown that for equally thick ferromagnetic layers (symmetric junctions) the long-range spin-triplet correlations are not dominant: For thin ferromagnetic layers all amplitudes are equally large, while for thick layers the long range triplet amplitude is very small. It is shown that for noncollinear magnetizations the long-range proximity effect can be dominant in highly non-symmetric SF1F2S junctions with particularly thin F1 and thick F2 ferromagnetic layers. We find that dominant triplet correlations in Josephson junctions with ferromagnetic bilayer always give dominant second harmonics in current-phase relations at low temperatures.

  1. Efficient Algorithms for Computing the Triplet and Quartet Distance Between Trees of Arbitrary Degree

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Fagerberg, Rolf; Mailund, Thomas;

    2013-01-01

    ), respectively, and counting how often the induced topologies in the two input trees are different. In this paper we present efficient algorithms for computing these distances. We show how to compute the triplet distance in time O(n log n) and the quartet distance in time O(d n log n), where d is the maximal...... degree of any node in the two trees. Within the same time bounds, our framework also allows us to compute the parameterized triplet and quartet distances, where a parameter is introduced to weight resolved (binary) topologies against unresolved (non-binary) topologies. The previous best algorithm for...... computing the triplet and parameterized triplet distances have O(n2) running time, while the previous best algorithms for computing the quartet distance include an O(d9 n log n) time algorithm and an O(n2.688) time algorithm, where the latter can also compute the parameterized quartet distance. Since d ≤ n...

  2. Intra-molecular Triplet Energy Transfer is a General Approach to Improve Organic Fluorophore Photostability

    Science.gov (United States)

    Zheng, Qinsi; Jockusch, Steffen; Rodríguez-Calero, Gabriel G.; Zhou, Zhou; Zhao, Hong; Altman, Roger B.; Abruña, Héctor D.; Blanchard, Scott C.

    2015-01-01

    Bright, long-lasting and non-phototoxic organic fluorophores are essential to the continued advancement of biological imaging. Traditional approaches towards achieving photostability, such as the removal of molecular oxygen and the use of small-molecule additives in solution, suffer from potentially toxic side effects, particularly in the context of living cells. The direct conjugation of small-molecule triplet state quenchers, such as cyclooctatetraene (COT), to organic fluorophores has the potential to bypass these issues by restoring reactive fluorophore triplet states to the ground state through intra-molecular triplet energy transfer. Such methods have enabled marked improvement in cyanine fluorophore photostability spanning the visible spectrum. However, the generality of this strategy to chemically and structurally diverse fluorophore species has yet to be examined. Here, we show that the proximal linkage of COT increases the photon yield of a diverse range of organic fluorophores widely used in biological imaging applications, demonstrating that the intra-molecular triplet energy transfer mechanism is a potentially general approach for improving organic fluorophore performance and photostability. PMID:26700693

  3. Maternal and Fetal Outcomes of Triplet Gestation in a Tertiary Hospital in Oman

    Directory of Open Access Journals (Sweden)

    Maryam Al-Shukri

    2014-05-01

    Full Text Available Objectives: The aim of this study was to describe the fetal and maternal outcomes of triplet gestation and to report on the maternal characteristics of those pregnancies in a tertiary care centre in Oman. Methods: A retrospective study was undertaken of all triplet pregnancies delivered at Sultan Qaboos University Hospital, Muscat, Oman, between January 2009 and December 2011. Results: Over the three-year study period, there were 9,140 deliveries. Of these, there were 18 triplet pregnancies, giving a frequency of 0.2%. The mean gestational age at delivery was 31.0 ± 3.0 weeks, and the mean birth weight was 1,594 ± 460 g. The most common maternal complications were preterm labour in 13 pregnancies (72.2%, gestational diabetes in 7 (39% and gestational hypertension in 5 (28%. Of the total deliveries, there were 54 neonates. Neonatal complications among these included hyaline membrane disease in 25 neonates (46%, hyperbilirubinaemia in 24 (43%, sepsis in 18 (33% and anaemia in 8 (15%. The perinatal mortality rate was 55 per 1,000 births. Conclusion: The maternal and neonatal outcomes of triplet pregnancies were similar to those reported in other studies.

  4. Field Tolerances for the Triplet Quadrupoles of the LHC High Luminosity Lattice

    Energy Technology Data Exchange (ETDEWEB)

    Nosochkov, Yuri; Cai, Y.; Jiao, Y.; Wang, M-H.; /SLAC; Fartoukh, S.; Giovannozzi, M.; Maria, R.de; McIntosh, E.

    2012-06-25

    It has been proposed to implement the so-called Achromatic Telescopic Squeezing (ATS) scheme in the LHC high luminosity (HL) lattice to reduce beta functions at the Interaction Points (IP) up to a factor of 8. As a result, the nominal 4.5 km peak beta functions reached in the Inner Triplets (IT) at collision will be increased by the same factor. This, therefore, justifies the installation of new, larger aperture, superconducting IT quadrupoles. The higher beta functions will enhance the effects of the triplet quadrupole field errors leading to smaller beam dynamic aperture (DA). To maintain the acceptable DA, the effects of the triplet field errors must be re-evaluated, thus specifying new tolerances. Such a study has been performed for the so-called '4444' collision option of the HL-LHC layout version SLHCV3.01, where the IP beta functions are reduced by a factor of 4 in both planes with respect to a pre-squeezed value of 60 cm at two collision points. The dynamic aperture calculations were performed using SixTrack. The impact on the triplet field quality is presented.

  5. The anaerobic photolysis of lens α-crystallin: evidence for triplet state mediated photodamage

    International Nuclear Information System (INIS)

    Anaerobic solutions of lens α-crystallin were subjected to near-UV (>295) irradiation, and the photoproducts were analyzed by fluorescence and room-temperature phosphorescence spectroscopy. This report is the first demonstration of a long-lived triplet state associated with a protein photolysis product. (author)

  6. Thermodynamic properties of the phase transitions in a class of spin-triplet ferromagnetic superconductors

    International Nuclear Information System (INIS)

    Magnetic susceptibility, entropy and specific heat are calculated at the equilibrium points of phase transition to a phase of coexistence of ferromagnetic order and superconductivity in a new class of spin-triplet ferromagnetic superconductors. The results are discussed in a view of application to metallic ferromagnets as UGe2, ZrZn2, URhGe. (authors)

  7. How disorder controls the kinetics of triplet charge recombination in semiconducting organic polymer photovoltaics.

    Science.gov (United States)

    Bittner, Eric R; Lankevich, Vladimir; Gélinas, Simon; Rao, Akshay; Ginger, David A; Friend, Richard H

    2014-10-14

    Recent experiments by Rao et al. (Nature, 2013, 500, 435-439) indicate that recombination of triplet charge-separated states is suppressed in organic polymer-fullerene based bulk-heterojunction (BHJ) photovoltaic cells exhibiting a high degree of crystallinity in the fullerene phase relative to systems with more disorder. In this paper, we use a series of Frenkel-exciton lattice models to rationalize these results in terms of wave-function localization, interface geometry, and density of states. In one-dimensional co-linear and co-facial models of the interface, increasing local energetic disorder in one phase localizes the interfacial triplet charge-transfer ((3)CT) states and increases the rate at which these states relax to form lower-energy triplet excitons. In two dimensional BHJ models, energetic disorder within the fullerene phase plays little role in further localizing states pinned to the interface. However, inhomogeneous broadening introduces strong coupling between the interfacial (3)CT and nearby fullerene triplet excitons and can enhance the decay of these states in systems with higher degrees of energetic disorder. PMID:24922118

  8. Early fetal reduction of dichorionic triplets to dichorionic twin or singleton pregnancies: a retrospective study.

    Science.gov (United States)

    Lin, Haiyan; Wen, Ya; Li, Yu; Chen, Xiaoli; Yang, Dongzi; Zhang, Qingxue

    2016-05-01

    A retrospective study conducted in an academic reproductive medicine centre evaluated the feasibility and safety of early fetal reduction in dichorionic triplets to dichorionic twin or singleton pregnancies. Thirty-three dichorionic triplets that underwent early transvaginal fetal reduction mechanically between 2002 and 2013 were included, of which 21 patients underwent fetal reduction to dichorionic twins (Group A) and 12 patients underwent fetal reduction to a singleton pregnancy (Group B). A further 84 patients with trichorionic triplets reduced to twins were included as the control group (Group C). The main outcome measures were live birth and preterm labour rates. Both early and late spontaneous abortion rates, were similar in group A compared with groups B and C. Gestational age at delivery was significantly lower in group C versus group A (P = 0.02). The preterm labour rate in group A, which was comparable with that in group C, was greater than in group B, but not significantly. Neonatal birth weight, low birth weight rate and neonatal body height were similar among groups. Small for gestational age rates were comparable. Live birth rates were similar among the groups. Early transvaginal fetal reduction for dichorionic triplets to dichorionic twins may be feasible and safe. PMID:26997475

  9. Ultrafast electronic and vibrational dynamics in brominated aluminum corroles: Energy relaxation and triplet formation

    Directory of Open Access Journals (Sweden)

    T. Stensitzki

    2016-07-01

    Full Text Available We combined femtosecond (fs VIS pump–IR probe spectroscopy with fs VIS pump–supercontinuum probe spectroscopy to characterize the photoreaction of the hexacoordinated Al(tpfc-Br8(py2 in a comprehensive way. Upon fs excitation at ∼400 nm in the Soret band, the excitation energy relaxes with a time constant of (250 ± 80 fs to the S2 and S1 electronic excited states. This is evident from the rise time of the stimulated emission signal in the visible spectral range. On the same time scale, narrowing of broad infrared signals in the C=C stretching region around 1500 cm−1 is observed. Energy redistribution processes are visible in the vibrational and electronic dynamics with time constants between ∼2 ps and ∼20 ps. Triplet formation is detected with a time constant of (95 ± 3 ps. This is tracked by the complete loss of stimulated emission. Electronic transition of the emerging triplet absorption band overlaps considerably with the singlet excited state absorption. In contrast, two well separated vibrational marker bands for triplet formation were identified at 1477 cm−1 and at 1508 cm−1. These marker bands allow a precise identification of triplet dynamics in corrole systems.

  10. Ultrafast electronic and vibrational dynamics in brominated aluminum corroles: Energy relaxation and triplet formation.

    Science.gov (United States)

    Stensitzki, T; Yang, Y; Berg, A; Mahammed, A; Gross, Z; Heyne, K

    2016-07-01

    We combined femtosecond (fs) VIS pump-IR probe spectroscopy with fs VIS pump-supercontinuum probe spectroscopy to characterize the photoreaction of the hexacoordinated Al(tpfc-Br8)(py)2 in a comprehensive way. Upon fs excitation at ∼400 nm in the Soret band, the excitation energy relaxes with a time constant of (250 ± 80) fs to the S2 and S1 electronic excited states. This is evident from the rise time of the stimulated emission signal in the visible spectral range. On the same time scale, narrowing of broad infrared signals in the C=C stretching region around 1500 cm(-1) is observed. Energy redistribution processes are visible in the vibrational and electronic dynamics with time constants between ∼2 ps and ∼20 ps. Triplet formation is detected with a time constant of (95 ± 3) ps. This is tracked by the complete loss of stimulated emission. Electronic transition of the emerging triplet absorption band overlaps considerably with the singlet excited state absorption. In contrast, two well separated vibrational marker bands for triplet formation were identified at 1477 cm(-1) and at 1508 cm(-1). These marker bands allow a precise identification of triplet dynamics in corrole systems. PMID:27226980

  11. Stepwise excitation and level-crossing spectroscopy of the triplet D states of helium-4

    International Nuclear Information System (INIS)

    The fine-structure intervals of the lowest two triplet D states of 4He have been obtained by a new method: Ground-state atoms are excited by a discharge to the triplet metastable state, which then undergoes a two-step optical excitation to the triplet D states, where level-crossing measurements are made. The experimental results for 3D1-3D3 (MHz) are 1400.67 plus-or-minus 0.29 and 591.25 plus-or-minus 0.14 for the 3 3D and 4 3D states, respectively; for 3D2-3D3 (MHz) they are 75.97 plus-or-minus 0.23 and 36.15 plus-or-minus 0.24 for 3 3D and 4 3D. These values are much more precise than the previously available data, obtained by optical, particle-bombardment level crossing, or beam-foil quantum-beat spectroscopy, and are consistent with the previous data except for one case, where a previous measurement of 3 3D2-3 3D3 by electron bombardment level-crossing spectroscopy is believed to be in error. These new experimental values for the fine structures of the triplet D state of 4He clearly indicate the inadequateness of existing theoretical calculations of these fine structures

  12. The molecular photophysics of chlorophyl : a study of its triplet state

    NARCIS (Netherlands)

    Kleibeuker, J.F.

    1977-01-01

    The lowest excited triplet state T 0 of chlorophyll a , chlorophyll b , bacteriochlorophyll and corresponding pheophytins has been studied by magnetic resonance and optical spectroscopy. Zero field splitting (US) parameters D and E, populating rates, a

  13. Long-range spin-triplet proximity effect in Josephson junctions with multilayered ferromagnets

    Energy Technology Data Exchange (ETDEWEB)

    Trifunovic, Luka [Department of Physics, University of Belgrade (RS); Department of Physics, University of Basel (Switzerland); Radovic, Zoran [Department of Physics, University of Belgrade (RS)

    2011-07-01

    We study theoretically the Josephson effect and pairing correlations in planar SF{sub 1}F{sub 2}S junctions that consist of conventional superconductors (S) connected through two metallic monodomain ferromagnets (F{sub 1} and F{sub 2}) with transparent interfaces. We solve self-consistently the Eilenberger equations for arbitrary orientation of in-plane magnetizations in the clean limit and for moderate disorder in ferromagnets. Both singlet and triplet pair amplitudes and the Josephson current-phase relations are calculated numerically. It is shown that for equally thick ferromagnetic layers (symmetric junctions) the long-range spin-triplet correlations are not dominant: For thin ferromagnetic layers all amplitudes are equally large, while for thick layers the long range triplet amplitude is very small. It is shown that for noncollinear magnetizations the long-range proximity effect can be dominant in highly non-symmetric SF{sub 1}F{sub 2}S junctions with particularly thin F{sub 1} and thick F{sub 2} ferromagnetic layers. We find that dominant triplet correlations in Josephson junctions with ferromagnetic bilayer always give dominant second harmonics in current-phase relations at low temperatures.

  14. Quadrupole Magnet Error Sensitivities for FODO-Cell and Triplet Lattices in the LCLS Undulator

    International Nuclear Information System (INIS)

    The error sensitivities of quadrupole magnets in the LCLS FEL undulator are compared for a FODO-cell lattice and for a triplet lattice. The comparisons are made at a radiation wavelength of 1.5 (angstrom), where electron-to-photon phase errors are very sensitive to small trajectory variations in misaligned quadrupoles between the undulator sections. The results show that the triplet lattice is extremely sensitive, with triplet pitch and yaw alignment tolerances of ∼100 (micro)rad. The FODO-cell lattice, with its shorter, weaker quadrupoles is much more error tolerant with pitch and yaw tolerances of ∼2.5 mrad. Several other magnet errors are examined and categorized as trajectory, phase slip, and beam size effects. In nearly all cases, the FODO-cell lattice is much less sensitive with technologically achievable tolerance levels, while the triplet lattice tolerances are, in many cases, near achievable limits and may not be sustainable over the long term. Table 2 presents a brief tolerance comparison for the two lattice types

  15. Isolation of proximity-induced triplet pairing channel in a superconductor/ferromagnet spin valve

    Science.gov (United States)

    Leksin, P. V.; Garif'yanov, N. N.; Kamashev, A. A.; Validov, A. A.; Fominov, Ya. V.; Schumann, J.; Kataev, V.; Thomas, J.; Büchner, B.; Garifullin, I. A.

    2016-03-01

    We have studied the proximity-induced superconducting triplet pairing in CoOx/Py1/Cu/Py2/Cu/Pb spin-valve structure (where Py = Ni0.81Fe0.19 ). By optimizing the parameters of this structure we found a triplet channel assisted full switching between the normal and superconducting states. To observe an "isolated" triplet spin-valve effect we exploited the oscillatory feature of the magnitude of the ordinary spin-valve effect Δ Tc in the dependence of the Py2-layer thickness dP y 2. We determined the value of dP y 2 at which Δ Tc caused by the ordinary spin-valve effect (the difference in the superconducting transition temperature Tc between the antiparallel and parallel mutual orientation of magnetizations of the Py1 and Py2 layers) is suppressed. For such a sample a "pure" triplet spin-valve effect which causes the minimum in Tc at the orthogonal configuration of magnetizations has been observed.

  16. Precision spectroscopy with ultracold {sup 87}Rb{sub 2} triplet molecules

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, Christoph

    2011-10-19

    In this thesis I report precision spectroscopy with ultracold {sup 87}Rb{sub 2} triplet molecules where we use lasers to couple the states in different molecular potentials. We study in detail states of the a {sup 3} sum {sup +}{sub u} and (1) {sup 3} sum {sup +}{sub g} potentials. These states are of great importance for transferring weakly bound molecules to the ro-vibrational triplet ground state via states of the excited potential. As most experiments start from molecules in their X {sup 1} sum {sup +}{sub g} ground state, the triplet states were hard to access via dipole transitions and remained largely unexplored. The measurements presented in this thesis are the first detailed study of diatomic {sup 87}Rb{sub 2} molecules in these states. Our experiments start with an ultracold cloud of {sup 87}Rb atoms. We then load this cloud into an optical lattice where we use a magnetic Feshbach resonance at 1007.4 G to perform a Feshbach association. After we have removed all unbound atoms, we end up with a pure sample of weakly bound Feshbach molecules inside the optical lattice. The optical lattice prevents these molecules from colliding with each other which results in molecular lifetimes on the order of a few hundred milliseconds. In the first set of experiments, we use a laser coupling the Feshbach state to the excited (1) {sup 3} sum {sup +}{sub g} triplet state to map out its low-lying vibrational (v = 0.. 15), rotational, hyperfine, and Zeeman structure. The experimental results are in good agreement with calculations done by Marius Lysebo and Prof. Leif Veseth. We then map out in detail the vibrational, rotational, hyperfine, and Zeeman structure of the a {sup 3} sum {sup +}{sub u} triplet ground state using dark state spectroscopy with levels in the (1) {sup 3} sum {sup +}{sub g} potential as an intermediate state. In this scheme we are able to access molecules in triplet states because our Feshbach state has strong triplet character. Interestingly, it

  17. Parenting Stress, Infant Emotion Regulation, Maternal Sensitivity, and the Cognitive Development of Triplets: A Model for Parent and Child Influences in a Unique Ecology

    Science.gov (United States)

    Feldman, Ruth; Eidelman, Arthur I.; Rotenberg, Noa

    2004-01-01

    To examine the development of triplets, 23 sets of triplets were matched with 23 sets of twins and 23 singletons (N138). Maternal sensitivity was observed at newborn, 3, 6, and 12 months, and infants' cognitive and symbolic skills at 1 year. Triplets received lower maternal sensitivity across infancy and exhibited poorer cognitive competencies…

  18. Aqueous secondary organic aerosol (SOA) production from the oxidation of phenols by triplet excited state organics

    Science.gov (United States)

    Smith, J.; Yu, L.; Zhang, Q.; Anastasio, C.

    2011-12-01

    Recent literature has shown that atmospheric condensed-phase chemistry can play a significant role in the evolution of organic aerosols, including the formation of secondary organic aerosol (SOA). SOA formation from the oxidation of volatile organic compounds (VOCs) in the aqueous phase has largely focused on oxidations involving the hydroxyl radical and other oxidants, such as photochemically created triplet excited states, have not been fully investigated. Phenolic compounds are one of the primary carbon emission classes from biomass and wood combustion and have significant water solubility. Once in the aqueous phase, phenolic compounds can react with the triplet excited states of non-phenolic aromatic carbonyls (NPCs), particle-bound organics that are also emitted in large quantities from wood combustion. The oxidation of phenolic species in the condensed phase by triplet excited states can result in the production of SOA. A main goal of this study was to investigate bulk solution reaction kinetics under atmospherically relevant conditions in order to ascertain how these reactions can impact aqueous-phase SOA production. In our experiments, we studied the reactions of five phenols (phenol, guaiacol, syringol, catechol, and resorcinol) with the triplet state of 3,4-dimethoxybenzaldehyde (34-DMB) during simulated solar radiation. We have characterized the impacts of pH, ionic strength and reactant concentrations on the reaction behavior of this system. In addition, we analyzed the SOA formed using high-resolution aerosol mass spectrometry, ion chromatography, and liquid chromatography-mass spectrometry to infer the reaction mechanisms. Our evidence suggests that under atmospherically relevant conditions, triplet excited states can be the dominant oxidant of phenolics and contribute significantly to the total SOA budget.

  19. Observation of spin-triplet supercurrent in Co-based Josephson junctions

    Science.gov (United States)

    Birge, Norman

    2011-03-01

    When a superconductor (S) and a ferromagnet (F) are put into contact with each other, the combined S/F system may exhibit altogether new properties. There is a proximity effect where pair correlations from S penetrate into F, but these correlations decay over a very short distance due to the large exchange splitting between the spin-up and spin-down electron bands in F. Theory predicts that, under certain conditions, electron pair correlations can be generated with spin-triplet rather than spin-singlet symmetry. The two electrons in such a spin-triplet pair have parallel spins and are not subject to the exchange splitting in F; hence they propagate long distances. We have measured a long-range supercurrent in Josephson junctions of the form S/X/N/SAF/N/X/S, where S is a superconductor (Nb), N is a normal metal (Cu), SAF is a synthetic antiferromagnet of the form Co/Ru/Co, and X is a thin ferromagnetic layer necessary to induce spin-triplet correlations in the structure. Spin-triplet correlations are generated due to non-collinearity of the magnetizations in each X layer and the nearest Co layer. Using X = PdNi, CuNi, and Ni, we observe enhancements of the critical current of up to 300 times relative to similar samples lacking the X layers. We also observe a large additional enhancement of the spin-triplet supercurrent after the samples are magnetized in a large field. This result is counter-intuitive, since one would expect magnetizing the samples to suppress the occurrence of non-collinear magnetization. We will present a model of the SAF magnetization structure that explains these intriguing results. Work supported by the U.S. Dept. of Energy under grant DE-FG02-06ER46341.

  20. Associated Production of the Charged and Neutral Higgs Bosons at the ILC within the Higgs Triplet Model

    Science.gov (United States)

    Zhang, Yan-Ju; Cao, Jun; Zhang, Wen-Qing

    2016-09-01

    The Higgs Triplet Model (HTM) predicts the existences of the extra neutral scalars H i ( H i = H, A) and the charged Higgs bosons ( H ± and H ±±). In this work, we make a systematic investigation for the associated production of the singly-charged and neutral Higgs bosons via the processes: e+e-→ H+W-H and e+e-→ H+W-A. From the numerical evaluations for the production cross sections and relevant phenomenological analysis we find that (i) the production rates of these processes can reach the level of several fb with reasonable parameter values; (ii) due to the large production rates and small backgrounds, the signals of these scalars might be detected via these processes at the future ILC experiments; and (iii) for the case of m_{Hi}> m_{H^{± }}> m_{H^{± ± }}, the cascade decay modes Hito H^{± }W^{∓ ast } with H^{± }to H^{± ± }W^{∓ ast } would lead to production of H ++ H - accompanied by several virtual W bosons. Such characteristic feature can help us to distinguish the HTM from the Two-Higgs-Doublet Model (2HDM) and the Minimal Supersymmetric Model (MSSM).

  1. Computational Estimate of the Photophysical Capabilities of Four Series of Organometallic Iron(II) Complexes.

    Science.gov (United States)

    Dixon, Isabelle M; Boissard, Gauthier; Whyte, Hannah; Alary, Fabienne; Heully, Jean-Louis

    2016-06-01

    In this study, we examine a large range of organometallic iron(II) complexes with the aim of computationally identifying the most promising ones in terms of photophysical properties. These complexes combine polypyridine, bis(phosphine), and carbon-bound ligands. Density functional theory has allowed us to establish a comparative Jablonski diagram displaying the lowest singlet, triplet, and quintet states. All of the proposed FeN5C or FeN3P2C complexes unfavorably possess a lowest triplet state of metal-centered (MC) nature. Among the FeN4C2 and FeN2P2C2 series, the carbene complexes display the least favorable excited-state distribution, also having a low-lying (3)MC state. Validating our design strategy, we are now able to propose seven iron(II) complexes displaying a lowest excited state of triplet metal-to-ligand charge-transfer nature. PMID:27228301

  2. Structural Control of (1)A(2u)-to-(3)A(2u) Intersystem Crossing in Diplatinum(II,II) Complexes

    Czech Academy of Sciences Publication Activity Database

    Durrell, A. C.; Keller, G. E.; Lam, Y.; Ch.; Sýkora, Jan; Vlček Jr., Antonín; Gray, H. B.

    2012-01-01

    Roč. 134, č. 34 (2012), s. 14201-14207. ISSN 0002-7863 R&D Projects: GA MŠk(CZ) ME10124 Institutional support: RVO:61388955 Keywords : TRIPLET EXCITED-STATE * BINUCLEAR PLATINUM (II) PHOTOCHEMISTRY * ELECTRON-TRANSFER REACTIONS Subject RIV: CG - Electrochemistry Impact factor: 10.677, year: 2012

  3. Contribution of NMDA, GABAA and GABAB receptors and l-arginine-NO-cGMP, MEK1/2 and CaMK-II pathways in the antidepressant-like effect of 7-fluoro-1,3-diphenylisoquinoline-1-amine in mice.

    Science.gov (United States)

    Pesarico, Ana Paula; Stangherlin, Eluza Curte; Rosa, Suzan Gonçalves; Mantovani, Anderson C; Zeni, Gilson; Nogueira, Cristina Wayne

    2016-07-01

    It has been reported that the antidepressant-like effect of 7-fluoro-1,3-diphenylisoquinoline-1-amine (FDPI) may result from the modulation of brain monoaminergic systems. However, the mechanisms of FDPI action are not fully understood. The aim of this study was to investigate the contribution of N-methyl-d-aspartate (NMDA) and gamma-aminobutyric acid (GABA) systems as well as l-arginine-nitric oxide-(NO)-cyclic guanosine monophosphate-(cGMP), mitogen-activated protein/extracellular signal-regulated kinase (MEK1/2) and Ca(2+)/calmodulin-dependent protein kinase II (CaMK-II) signaling pathways in the antidepressant-like effect of FDPI in the mouse forced swimming test (FST). The levels of NO and uptake of [(3)H]glutamate and [(3)H]GABA were determined in prefrontal cortices of Swiss mice. Pretreatments with NMDA (0.1 pmol/site, i.c.v., a NMDA receptor agonist), bicuculline (1mg/kg, i.p., a GABAA receptor antagonist), phaclofen (2mg/kg, i.p., a GABAB receptor antagonist) and l-arginine (750mg/kg, i.p., a NO precursor), KN-62 (1μg/site, a CaMK-II inhibitor), U0126 (5μg/site, a MEK1/2 inhibitor) and PD09058 (5μg/site, a MEK1/2 inhibitor) blocked the antidepressant-like effect of FDPI, at a dose of 1mg/kg, in the FST. ODQ (30 pmol/site, i.c.v., a soluble guanylate cyclase (sGC) inhibitor) in combination with a sub-effective dose of FDPI (0.1mg/kg, i.g.) reduced the immobility time in the FST. The administration of FDPI (50mg/kg) to mice increased the glutamate uptake and reduced NO levels in the prefrontal cortex of mice. The results suggest a contribution of NMDA, GABAA and GABAB receptors and l-arginine-NO-cGMP pathway in the antidepressant-like action of FDPI in mice, and this effect is related to CaMK-II and MEK 1/2 activation. PMID:27112660

  4. Selective Preference of Parallel DNA Triplexes Is Due to the Disruption of Hoogsteen Hydrogen Bonds Caused by the Severe Nonisostericity between the G*GC and T*AT Triplets

    Science.gov (United States)

    Goldsmith, Gunaseelan; Rathinavelan, Thenmalarchelvi; Yathindra, Narayanarao

    2016-01-01

    Implications of DNA, RNA and RNA.DNA hybrid triplexes in diverse biological functions, diseases and therapeutic applications call for a thorough understanding of their structure-function relationships. Despite exhaustive studies mechanistic rationale for the discriminatory preference of parallel DNA triplexes with G*GC & T*AT triplets still remains elusive. Here, we show that the highest nonisostericity between the G*GC & T*AT triplets imposes extensive stereochemical rearrangements contributing to context dependent triplex destabilisation through selective disruption of Hoogsteen scheme of hydrogen bonds. MD simulations of nineteen DNA triplexes with an assortment of sequence milieu reveal for the first time fresh insights into the nature and extent of destabilization from a single (non-overlapping), double (overlapping) and multiple pairs of nonisosteric base triplets (NIBTs). It is found that a solitary pair of NIBTs, feasible either at a G*GC/T*AT or T*AT/G*GC triplex junction, does not impinge significantly on triplex stability. But two overlapping pairs of NIBTs resulting from either a T*AT or a G*GC interruption disrupt Hoogsteen pair to a noncanonical mismatch destabilizing the triplex by ~10 to 14 kcal/mol, implying that their frequent incidence in multiples, especially, in short sequences could even hinder triplex formation. The results provide (i) an unambiguous and generalised mechanistic rationale for the discriminatory trait of parallel triplexes, including those studied experimentally (ii) clarity for the prevalence of antiparallel triplexes and (iii) comprehensive perspectives on the sequence dependent influence of nonisosteric base triplets useful in the rational design of TFO’s against potential triplex target sites. PMID:27010368

  5. Selective Preference of Parallel DNA Triplexes Is Due to the Disruption of Hoogsteen Hydrogen Bonds Caused by the Severe Nonisostericity between the G*GC and T*AT Triplets.

    Science.gov (United States)

    Goldsmith, Gunaseelan; Rathinavelan, Thenmalarchelvi; Yathindra, Narayanarao

    2016-01-01

    Implications of DNA, RNA and RNA.DNA hybrid triplexes in diverse biological functions, diseases and therapeutic applications call for a thorough understanding of their structure-function relationships. Despite exhaustive studies mechanistic rationale for the discriminatory preference of parallel DNA triplexes with G*GC & T*AT triplets still remains elusive. Here, we show that the highest nonisostericity between the G*GC & T*AT triplets imposes extensive stereochemical rearrangements contributing to context dependent triplex destabilisation through selective disruption of Hoogsteen scheme of hydrogen bonds. MD simulations of nineteen DNA triplexes with an assortment of sequence milieu reveal for the first time fresh insights into the nature and extent of destabilization from a single (non-overlapping), double (overlapping) and multiple pairs of nonisosteric base triplets (NIBTs). It is found that a solitary pair of NIBTs, feasible either at a G*GC/T*AT or T*AT/G*GC triplex junction, does not impinge significantly on triplex stability. But two overlapping pairs of NIBTs resulting from either a T*AT or a G*GC interruption disrupt Hoogsteen pair to a noncanonical mismatch destabilizing the triplex by ~10 to 14 kcal/mol, implying that their frequent incidence in multiples, especially, in short sequences could even hinder triplex formation. The results provide (i) an unambiguous and generalised mechanistic rationale for the discriminatory trait of parallel triplexes, including those studied experimentally (ii) clarity for the prevalence of antiparallel triplexes and (iii) comprehensive perspectives on the sequence dependent influence of nonisosteric base triplets useful in the rational design of TFO's against potential triplex target sites. PMID:27010368

  6. Selective Preference of Parallel DNA Triplexes Is Due to the Disruption of Hoogsteen Hydrogen Bonds Caused by the Severe Nonisostericity between the G*GC and T*AT Triplets.

    Directory of Open Access Journals (Sweden)

    Gunaseelan Goldsmith

    Full Text Available Implications of DNA, RNA and RNA.DNA hybrid triplexes in diverse biological functions, diseases and therapeutic applications call for a thorough understanding of their structure-function relationships. Despite exhaustive studies mechanistic rationale for the discriminatory preference of parallel DNA triplexes with G*GC & T*AT triplets still remains elusive. Here, we show that the highest nonisostericity between the G*GC & T*AT triplets imposes extensive stereochemical rearrangements contributing to context dependent triplex destabilisation through selective disruption of Hoogsteen scheme of hydrogen bonds. MD simulations of nineteen DNA triplexes with an assortment of sequence milieu reveal for the first time fresh insights into the nature and extent of destabilization from a single (non-overlapping, double (overlapping and multiple pairs of nonisosteric base triplets (NIBTs. It is found that a solitary pair of NIBTs, feasible either at a G*GC/T*AT or T*AT/G*GC triplex junction, does not impinge significantly on triplex stability. But two overlapping pairs of NIBTs resulting from either a T*AT or a G*GC interruption disrupt Hoogsteen pair to a noncanonical mismatch destabilizing the triplex by ~10 to 14 kcal/mol, implying that their frequent incidence in multiples, especially, in short sequences could even hinder triplex formation. The results provide (i an unambiguous and generalised mechanistic rationale for the discriminatory trait of parallel triplexes, including those studied experimentally (ii clarity for the prevalence of antiparallel triplexes and (iii comprehensive perspectives on the sequence dependent influence of nonisosteric base triplets useful in the rational design of TFO's against potential triplex target sites.

  7. High velocity blue-shifted FeII absorption in the dwarf star-forming galaxy PHL293B: Evidence for a wind driven supershell?

    CERN Document Server

    Terlevich, R; Bosch, G; Diaz, A I; Hagele, G; Cardaci, M; Firpo, V

    2014-01-01

    X-shooter and ISIS WHT spectra of the starforming galaxy PHL 293B also known as A2228-00 and SDSS J223036.79-000636.9 are presented in this paper. We find broad (FWHM = 1000km/s) and very broad (FWZI = 4000km/s) components in the Balmer lines, narrow absorption components in the Balmer series blueshifted by 800km/s, previously undetected FeII multiplet (42) absorptions also blueshifted by 800km/s, IR CaII triplet stellar absorptions consistent with [Fe/H] < -2.0 and no broad components or blushifted absorptions in the HeI lines. Based on historical records, we found no optical variability at the 5 sigma level of 0.02 mag between 2005 and 2013 and no optical variability at the level of 0.1mag for the past 24 years. The lack of variability rules out transient phenomena like luminous blue variables or SN IIn as the origin of the blue shifted absorptions of HI and FeII. The evidence points to either a young and dense expanding supershell or a stationary cooling wind, in both cases driven by the young cluster w...

  8. Integrating a Triplet-triplet Annihilation Up-conversion System to Enhance Dye-sensitized Solar Cell Response to Sub-bandgap Light

    Science.gov (United States)

    Nattestad, Andrew; Cheng, Yuen Yap; MacQueen, Rowan W.; Wallace, Gordon G.; Schmidt, Timothy W.

    2014-01-01

    The poor response of dye-sensitized solar cells (DSCs) to red and infrared light is a significant impediment to the realization of higher photocurrents and hence higher efficiencies. Photon up-conversion by way of triplet-triplet annihilation (TTA-UC) is an attractive technique for using these otherwise wasted low energy photons to produce photocurrent, while not interfering with the photoanodic performance in a deleterious manner. Further to this, TTA-UC has a number of features, distinct from other reported photon up-conversion technologies, which renders it particularly suitable for coupling with DSC technology. In this work, a proven high performance TTA-UC system, comprising a palladium porphyrin sensitizer and rubrene emitter, is combined with a high performance DSC (utilizing the organic dye D149) in an integrated device. The device shows an enhanced response to sub-bandgap light over the absorption range of the TTA-UC sub-unit resulting in the highest figure of merit for up-conversion assisted DSC performance to date. PMID:25285452

  9. The vector resonance triplet with the direct coupling to the third quark generation

    CERN Document Server

    Gintner, Mikulas

    2013-01-01

    The effective Lagrangian with scalar and vector resonances that might result from new strong physics beyond the SM is formulated and studied. In particular, the scalar resonance representing the recently discovered 125-GeV boson is complemented with the SU(2)_{L+R} triplet of hypothetical vector resonances. Motivated by experimental and theoretical considerations, the vector resonance is allowed to couple directly to the third quark generation only. The coupling is chiral-dependent and the interaction of the right top quark can differ from that of the right bottom quark. To estimate the applicability range of the effective Lagrangian the unitarity of the gauge boson scattering amplitudes is analyzed. The experimental fits and limits on the free parameters of the vector resonance triplet are investigated.

  10. Using less Quantum Resource for Probabilistic Controlled Teleportation of a Triplet W State

    Directory of Open Access Journals (Sweden)

    Xian-Ming Wang

    2012-10-01

    Full Text Available In a recent paper [CHIN. PHYS. LETT. Vol.26,No.7(2009070306 ], DONG et al. proposed a scheme for probabilistic controlled teleportation of a triplet W state using combined non-maximally entangled channel of two Einstein–Podolsky–Rosen (EPR states and one Greenberger–Horne–Zeilinger (GHZ state. In this paper ,only using one Einstein–Podolsky–Rosen (EPR state and one Greenberger–Horne–Zeilinger (GHZ state,the scheme for probabilistic controlled teleportation of a triplet W state is presented. Furthermore, Comparing with the widely used Bell-State measurement, Alice performs orthogonal complete basis measurement in the current work. Then Bob can faithfully reconstruct the original state by performing relevant unitary transformations. The total probability of successful teleportation is only dependent on channel coefficients of EPR state and GHZ state.  

  11. TripNet: A Method for Constructing Phylogenetic Networks from Triplets

    CERN Document Server

    Tusserkani, Ruzbeh; Poormohammadi, Hadi; Azadi, Azin

    2011-01-01

    We present TripNet, a method for constructing phylogenetic networks from triplets. We will present the motivations behind our approach and its theoretical and empirical justification. To demonstrate the accuracy and efficiency of TripNet, we performed two simulations and also applied the method to five published data sets: Kreitman's data, a set of triplets from real yeast data obtained from the Fungal Biodiversity Center in Utrecht, a collection of 110 highly recombinant Salmonella multi-locus sequence typing sequences, and nrDNA ITS and cpDNA JSA sequence data of New Zealand alpine buttercups of Ranunculus sect. Pseudadonis. Finally, we compare our results with those already obtained by other authors using alternative methods. TripNet, data sets, and supplementary files are freely available for download at (www.bioinf.cs.ipm.ir/softwares/tripnet).

  12. Quench Limit Calculation for Steady State Heat Deposits in LHC Inner Triplet Magnets

    CERN Document Server

    Cerutti, F; Esposito, L S; Siemko, A; Bocian, D

    2012-01-01

    In hadron colliders such as the LHC, the energy deposited in the superconductors by the particles lost from the beams or coming from the collision debris may provoke quenches detrimental to the accelerator operation. A Network Model is used to simulate the thermodynamic behavior of the superconducting magnets. In previous papers the validations of network model with measurements performed in the CERN and Fermilab magnet test facilities were presented. This model was subsequently used for thermal analysis of the current LHC inner triplet quadrupole magnets for beam energy of 3.5 TeV and 7.0 TeV. The detailed study of helium cooling channels efficiency for energy deposits simulated with FLUKA was performed. The expected LHC inner triplet magnets quench limit is presented.

  13. Superfluid phases of triplet pairing and rapid cooling of the neutron star in Cassiopeia A

    Directory of Open Access Journals (Sweden)

    Lev B. Leinson

    2015-02-01

    Full Text Available In a simple model it is demonstrated that the neutron star surface temperature evolution is sensitive to the phase state of the triplet superfluid condensate. A multicomponent triplet pairing of superfluid neutrons in the core of a neutron star with participation of several magnetic quantum numbers leads to neutrino energy losses exceeding the losses from the unicomponent pairing. A phase transition of the neutron condensate into the multicomponent state triggers more rapid cooling of superfluid core in neutron stars. This makes it possible to simulate an anomalously rapid cooling of neutron stars within the minimal cooling paradigm without employing any exotic scenarios suggested earlier for rapid cooling of isolated neutron star in Cassiopeia A.

  14. Does interchain stacking morphology contribute to the singlet-triplet interconversion dynamics in polymer heterojunctions?

    International Nuclear Information System (INIS)

    Time-dependent density functional theory (TD-DFT) is used to examine the effect of stacking in a model semiconducting polymer hetrojunction system consisting of two co-facially stacked oligomers. We find that the excited electronic states are highly sensitive to the alignment of the monomer units of the two chains. In the system we examined, the exchange energy is nearly identical to both the and band off-set at the heterojunction and to the exciton binding energy. Our results indicate that the triplet excitonic states are nearly degenerate with the singlet exciplex states opening the possibility for the interconversion of singlet and triplet electronic states at the heterojunction interface via spin-orbit coupling localized on the heteroatoms. Using Russell-Saunders theory, we estimate this interconversion rate to be approximately 700-800 ps, roughly a 5-10-fold increase compared to isolated organic polymer chains

  15. Does interchain stacking morphology contribute to the singlet-triplet interconversion dynamics in polymer heterojunctions?

    Science.gov (United States)

    Bittner, Eric R.; Burghardt, Irene; Friend, Richard H.

    2009-02-01

    Time-dependent density functional theory (TD-DFT) is used to examine the effect of stacking in a model semiconducting polymer hetrojunction system consisting of two co-facially stacked oligomers. We find that the excited electronic states are highly sensitive to the alignment of the monomer units of the two chains. In the system we examined, the exchange energy is nearly identical to both the and band off-set at the heterojunction and to the exciton binding energy. Our results indicate that the triplet excitonic states are nearly degenerate with the singlet exciplex states opening the possibility for the interconversion of singlet and triplet electronic states at the heterojunction interface via spin-orbit coupling localized on the heteroatoms. Using Russell-Saunders theory, we estimate this interconversion rate to be approximately 700-800 ps, roughly a 5-10-fold increase compared to isolated organic polymer chains.

  16. Triplet repeat DNA structures and human genetic disease: dynamic mutations from dynamic DNA

    Indian Academy of Sciences (India)

    Richard R Sinden; Vladimir N Potaman; Elena A Oussatcheva; Christopher E Pearson; Yuri L Lyubchenko; Luda S Shlyakhtenko

    2002-02-01

    Fourteen genetic neurodegenerative diseases and three fragile sites have been associated with the expansion of (CTG)n•(CAG)n, (CGG)n•(CCG)n, or (GAA)n•(TTC)n repeat tracts. Different models have been proposed for the expansion of triplet repeats, most of which presume the formation of alternative DNA structures in repeat tracts. One of the most likely structures, slipped strand DNA, may stably and reproducibly form within triplet repeat sequences. The propensity to form slipped strand DNA is proportional to the length and homogeneity of the repeat tract. The remarkable stability of slipped strand DNA may, in part, be due to loop-loop interactions facilitated by the sequence complementarity of the loops and the dynamic structure of three-way junctions formed at the loop-outs.

  17. Photopolymer material sensitized by xanthene dyes for holographic recording using forbidden singlet–triplet electronic transitions

    Science.gov (United States)

    Shelkovnikov, Vladimir; Vasiljev, Evgeny; Russkih, Vladimlen; Berezhnaya, Viktoria

    2016-07-01

    A new holographic photopolymer material is developed. The photopolymer material is sensitized by dyes of xanthene and thioxanthene series which contain iodine and bromine heavy atoms. Holographic recording was carried out during excitation of forbidden singlet–triplet electron transitions of dyes. Thioerythrosin triethylammonium was identified as the most effective sensitizer among a number of tested dyes. The spectral absorption area of the singlet–triplet electronic transition of the dye is conveyed in the red spectral range from 600 to 700 nm. The sensitivity of the photopolymer material to radiation with 633 nm wavelength is 180 mJ cm‑2. Optimization of concentration of the main components of the photopolymer compositions was carried out in order to achieve maximum efficiency of holographic recording.

  18. Beam Dynamics Requirements for the Powering Scheme of the HL-LHC Triplet

    CERN Document Server

    AUTHOR|(CDS)2075212; Fartoukh, Stephane; Giovannozzi, Massimo

    2015-01-01

    For the HL-LHC, β ∗ values as small as 15 cm are envisaged as baseline scenario for the high luminosity insertions IR1 and IR5, thus leading to an increase of the maximum β- functions in the inner triplet (IT). The larger beta-functions in the IT result in a higher sensitivity of the beam to any linear or non-linear, static or dynamic, field imperfections in the IT region. In this paper, we summarize accordingly the tolerances of the triplet power supplies in terms of current ripple, stability and reproducibility. Both the baseline IT powering scheme and other alternative schemes will be presented, the later reducing the tune shift caused by a current modulation and thus weakening its possible impact on the long term stability.

  19. The vector resonance triplet with the direct coupling to the third quark generation

    International Nuclear Information System (INIS)

    The effective Lagrangian with scalar and vector resonances that might result from new strong physics beyond the SM is formulated and studied. In particular, the scalar resonance representing the recently discovered 125-GeV boson is complemented with the SU(2)L+R triplet of hypothetical vector resonances. Motivated by experimental and theoretical considerations, the vector resonance is allowed to couple directly to the third quark generation only. The coupling is chiral-dependent and the interaction of the right top quark can differ from that of the right bottom quark. To estimate the applicability range of the effective Lagrangian the unitarity of the gauge boson scattering amplitudes is analyzed. The experimental fits and limits on the free parameters of the vector resonance triplet are investigated. (orig.)

  20. The vector resonance triplet with the direct coupling to the third quark generation

    Energy Technology Data Exchange (ETDEWEB)

    Gintner, Mikulas [University of Zilina, Physics Department, Zilina (Slovakia); Czech Technical University in Prague, Institute of Experimental and Applied Physics, Prague (Czech Republic); Juran, Josef [Czech Technical University in Prague, Institute of Experimental and Applied Physics, Prague (Czech Republic); Silesian University in Opava, Institute of Physics, Opava (Czech Republic)

    2013-10-15

    The effective Lagrangian with scalar and vector resonances that might result from new strong physics beyond the SM is formulated and studied. In particular, the scalar resonance representing the recently discovered 125-GeV boson is complemented with the SU(2){sub L+R} triplet of hypothetical vector resonances. Motivated by experimental and theoretical considerations, the vector resonance is allowed to couple directly to the third quark generation only. The coupling is chiral-dependent and the interaction of the right top quark can differ from that of the right bottom quark. To estimate the applicability range of the effective Lagrangian the unitarity of the gauge boson scattering amplitudes is analyzed. The experimental fits and limits on the free parameters of the vector resonance triplet are investigated. (orig.)