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Sample records for 4s giant resonance

  1. QRPA calculations of Giant Monopole Resonances

    NASA Astrophysics Data System (ADS)

    Avogadro, Paolo; Bertulani, Carlos; Nakatsukasa, Takashi

    2013-04-01

    We present calculations of giant monopole resonances obtained with a fully self consistent spherical quasiparticle random phase approximation (QRPA) on top of a Hartree-Fock-Bogoliubov (HFB) code. These results are compared with the most recent experiments on Sn and Cd isotopes to try to shed light on the abnormal softness of these isotopes. In the particle hole channel we use Skryme functionals while in the pairing channel we make use of density dependent contact interactions. The density dependence of the pairing interaction is explicitly taken into account.

  2. Systematics of Hot Giant Dipole Resonance Parameters

    NASA Astrophysics Data System (ADS)

    Schiller, Andreas; Thoennessen, Michael; McAlpine, Katherine

    2008-10-01

    The dependence of the Giant Dipole Resonance (GDR) width on spin and temperature is a much debated subject in the literature. A universal scaling law has been proposed by Kusnezov et al. [D. Kusnezov et al. Phys. Rev. Lett. 81,42 (1998)]@. Recently, we completed a literature survey of GDR parameters which provided us with a data set about five times as big as the one which was used by Kusnezov et al. [A. Schiller and M. Thoennessen, At. Data Nucl. Data Tables 93,49 (2007)]@. The Kusnezov scaling law is tested over this larger data set. The data is also broken down into subsets of data with common characteristics such as deformation. We will discuss the limits of applicability of the Kusnezov scaling law.

  3. Attosecond time delay in the photoionization of Mn in the region of the 3 p →3 d giant resonance

    NASA Astrophysics Data System (ADS)

    Dolmatov, V. K.; Kheifets, A. S.; Deshmukh, P. C.; Manson, S. T.

    2015-05-01

    Initial insight into time delay in Mn photoionization in the region of the 3 p →,3 d giant autoionization resonance is gained in the framework of the "spin-polarized" random-phase approximation with exchange. The dramatic effect of the giant autoionization resonance on the time delay of photoemission from the 3 d and 4 s valence subshells of the Mn atom is unraveled. Strong sensitivity of the time delay of the 4 s photoemission to the final-state term of the ion remainder [Mn+(4 s1,5S ) vs Mn+(4 s1,7S ) ] is discovered. It is shown that photoionization time delay in the autoionizing resonance region is explicitly associated with the resonance lifetime, which can thus be directly measured in attosecond time-delay experiments. Similar features are expected to emerge in photoionization time delays of other transition-metal and rare-earth atoms with half-filled subshells that possess giant autoionization resonances as well.

  4. Landau zeroth-sound and nuclear giant resonances

    NASA Astrophysics Data System (ADS)

    Strutinsky, V.; Magner, A.; Denisov, V.

    1984-10-01

    Analytical solution for the zeroth-sound in the infinite matter is used as a basis for constructing the distribution functions in finite-size nuclei. Simple characteristic equation is obtained which determines frequencies of isoscalar nuclear giant resonances due to the zeroth-sound modes coupled to the surface distortions.

  5. Excitation-energy dependence of the giant dipole resonance width

    NASA Astrophysics Data System (ADS)

    Enders, G.; Berg, F. D.; Hagel, K.; Kühn, W.; Metag, V.; Novotny, R.; Pfeiffer, M.; Schwalb, O.; Charity, R. J.; Gobbi, A.; Freifelder, R.; Henning, W.; Hildenbrand, K. D.; Holzmann, R.; Mayer, R. S.; Simon, R. S.; Wessels, J. P.; Casini, G.; Olmi, A.; Stefanini, A. A.

    1992-07-01

    High-energy γ rays have been measured in coincidence with heavy fragents in deeply inelastic reactions of 136Xe+48Ti at 18.5 MeV/nucleon. The giant dipole resonance (GDR) strength function is deduced from an analysis of the photon spectra within the statistical model. The GDR width Γ is studied as a function of the fragment excitation energy E*. A saturation at about Γ=10 MeV is observed for E*/A>=1.0 MeV/nucleon.

  6. Outward Migration of Giant Planets in Orbital Resonance

    NASA Astrophysics Data System (ADS)

    D'Angelo, G.; Marzari, F.

    2013-05-01

    A pair of giant planets interacting with a gaseous disk may be subject to convergent orbital migration and become locked into a mean motion resonance. If the orbits are close enough, the tidal gaps produced by the planets in the disk may overlap. This represents a necessary condition to activate the outward migration of the pair. However, a number of other conditions must also be realized in order for this mechanism to operate. We have studied how disk properties, such as turbulence viscosity, temperature, surface density gradient, mass, and age, may affect the outcome of the outward migration process. We have also investigated the implications on this mechanism of the planets' gas accretion. If the pair resembles Jupiter and Saturn, the 3:2 orbital resonance may drive them outward until they reach stalling radii for migration, which are within ~10 AU of the star for disks representative of the early proto-solar nebula. However, planet post-formation conditions in the disk indicate that such planets become typically locked in the 1:2 orbital resonance, which does not lead to outward migration. Planet growth via gas accretion tends to alter the planets' mass-ratio and/or the disk accretion rate toward the star, reducing or inhibiting outward migration. Support from NASA Outer Planets Research Program and NASA Origins of Solar Systems Program is gratefully acknowledged.

  7. Pygmy and giant dipole resonances in the nitrogen isotopes

    NASA Astrophysics Data System (ADS)

    Ma, Hai-Liang; Dong, Bao-Guo; Yan, Yu-Liang; Zhang, Huan-Qiao; Yuan, Da-Qing; Zhu, Shen-Yun; Zhang, Xi-Zhen

    2016-01-01

    The configuration-interaction shell model with the WBP10 effective interaction has been used to investigate the pygmy and giant dipole resonances in the nitrogen isotopes. Large enhancement of low-lying dipole strength, i.e., pygmy dipole resonances (PDRs), is predicted in the neutron-rich 17,18,19,20N. The nature of the PDRs is analyzed via the transition densities and transition matrix elements. It turns out these PDRs involve a larger amount of excitations between the 2 s 1 d and loosely bound 1 f 2 p shells. Combining with the transition densities, it is concluded that the PDRs in 17,18,19,20N are collective and due to the oscillation between the excess neutrons and the isospin saturated core. The isospin dependence of energy splitting and sum rule of isospin doublets is discussed. The theoretical energy splitting of isospin doublets can significantly deviate from the systematic values when nucleus is far away from the β -stability line. The ratios of T< and T> energy-weighted sum rule (EWSR) are consistently larger than the systematic values, and it is noticed that the calculated EWSR ratio over the systematic ratio increases with increasing isospin almost linearly. We also calculated the photoabsorption cross sections for the nitrogen isotopes. We proposed the normalization factors for 0 -1 ℏ ω and 2 -3 ℏ ω calculations. After the normalization, the shell model has well reproduced the experimental photoabsorption cross sections in N,1514, especially the detailed structure of resonances.

  8. Analytical model of a giant magnetostrictive resonance transducer

    NASA Astrophysics Data System (ADS)

    Sheykholeslami, M.; Hojjat, Y.; Ansari, S.; Cinquemani, S.; Ghodsi, M.

    2016-04-01

    Resonance transducers have been widely developed and studied, as they can be profitably used in many application such as liquid atomizing and sonar technology. The active element of these devices can be a giant magnetostrictive material (GMM) that is known to have significant energy density and good performance at high frequencies. The paper introduces an analytical model of GMM transducers to describe their dynamics in different working conditions and to predict any change in their performance. The knowledge of the transducer behavior, especially in operating conditions different from the ideal ones, is helpful in the design and fabrication of highly efficient devices. This transducer is design to properly work in its second mode of vibration and its working frequency is around 8000 Hz. Most interesting parameters of the device, such as quality factor, bandwidth and output strain are obtained from theoretical analysis.

  9. Driving Rabi oscillations at the giant dipole resonance in xenon

    NASA Astrophysics Data System (ADS)

    Pabst, Stefan; Wang, Daochen; Santra, Robin

    2015-11-01

    Free-electron lasers (FELs) produce short and very intense light pulses in the XUV and x-ray regimes. We investigate the possibility to drive Rabi oscillations in xenon with an intense FEL pulse by using the unusually large dipole strength of the giant dipole resonance (GDR). The GDR decays within less than 30 as due to its position, which is above the 4 d ionization threshold. We find that intensities around 1018W /cm2 are required to induce Rabi oscillations with a period comparable to the lifetime. The pulse duration should not exceed 100 as because xenon will be fully ionized within a few lifetimes. Rabi oscillations reveal themselves also in the photoelectron spectrum in the form of Autler-Townes splittings extending over several tens of electronvolts.

  10. Compilation of giant electric dipole resonances built on excited states

    SciTech Connect

    Schiller, A. . E-mail: schiller@nscl.msu.edu; Thoennessen, M.

    2007-07-15

    Giant Electric Dipole Resonance (GDR) parameters for {gamma} decay to excited states with finite spin and temperature are compiled. Over 100 original works have been reviewed and from some 70 of them, about 350 sets of hot GDR parameters for different isotopes, excitation energies, and spin regions have been extracted. All parameter sets have been brought onto a common footing by calculating the equivalent Lorentzian parameters. The current compilation is complementary to an earlier compilation by Samuel S. Dietrich and Barry L. Berman (At. Data Nucl. Data Tables 38 (1988) 199-338) on ground-state photo-neutron and photo-absorption cross sections and their Lorentzian parameters. A comparison of the two may help shed light on the evolution of GDR parameters with temperature and spin. The present compilation is current as of July 2006.

  11. Scalar resonance contributions to the dipion transition rates of {upsilon}(4S,5S) in the rescattering model

    SciTech Connect

    Meng Ce; Chao, K.-T.

    2008-04-01

    In order to explain the observed unusually large dipion transition rates of {upsilon}(10870), the scalar resonance contributions in the rescattering model to the dipion transitions of {upsilon}(4S) and {upsilon}(5S) are studied. Since the imaginary part of the rescattering amplitude is expected to be dominant, the large ratios of the transition rates of {upsilon}(10870), which is identified with {upsilon}(5S), to that of {upsilon}(4S) can be understood as mainly coming from the difference between the p values in their decays into open bottom channels, and the ratios are estimated numerically to be about 200-600 with reasonable choices of parameters. The absolute and relative rates of {upsilon}(5S){yields}{upsilon}(1S,2S,3S){pi}{sup +}{pi}{sup -} and {upsilon}(5S){yields}{upsilon}(1S)K{sup +}K{sup -} are roughly consistent with data. We emphasize that the dipion transitions observed for some of the newly discovered Y states associated with charmonia may have similar features to the dipion transitions of {upsilon}(5S). Measurements on the dipion transitions of {upsilon}(6S) could provide further tests for this mechanism.

  12. Giant Planets on Resonant Orbits: The Effect of Mass Growth

    NASA Astrophysics Data System (ADS)

    Marzari, Francesco; D'Angelo, Gennaro

    Two giant planets that undergo convergent migration, driven by tidal interactions with their gaseous disk, may become locked into a mean motion resonance (MMR). For planet masses similar to those of Jupiter (the internal planet) and Saturn and for typical post-formation (i.e., after planets have formed) disk conditions, capture occurs in the 2:1 MMR (D'Angelo and Marzari 2012). Capture in the 3:2 MMR may occur if the post-formation gas density around the planet locations is large enough (e.g., > ~2000 g/cm2 at ~1AU). This scenario, however, neglects the effects of ongoing gas accretion on the planets, which may be significant especially at large disk gas densities. In fact, recent work (Gressel et al. 2013; Keith and Wardle 2014), suggests that even if turbulence in the proximity of the planets is caused by MRI, gas accretion may still be vigorous. In particular, the MHD calculations of Gressel et al. (2013) resulted in accretion rates compatible to those derived from hydrodynamical calculations (D'Angelo et al. 2003; Bate et al. 2003). In order to address this issue, we perform hydrodynamical models of the evolution of a pair of planets that interact with each other and with the disk. The planets are initially locked in the 2:1 or 3:2 MMR. Gas accretion depends on the local disk mass. The large gas densities required for capture in the 3:2 MMR rapidly change the planet masses and mass ratio. Ensuing planet-planet interactions affect orbital eccentricities, leading to scattering and ejection episodes. The conditions required by 2:1 MMR locking can also produce a significant mass growth, if the local disk is sufficiently massive. For planets orbiting in the 1 AU region, however, the resonant configuration appears stable up to several Jupiter's masses.

  13. Systematics of Giant Electric Dipole Resonances in Hot, Rotating Nuclei

    NASA Astrophysics Data System (ADS)

    McAlpine, Katherine; Schiller, Andreas; Thoennessen, Michael

    2006-10-01

    The dependence of hot Giant Dipole Resonance (GDR) widths on spin, temperature, and mass is an exciting field of study. In 2001, Kusnezov et al. [1] developed a scaling law to predict the width as a function of these parameters. The law is a reliable description of their data set. Recently, Schiller and Thoennessen [2] prepared a compilation of GDR parameters built on excited states. The scaling law is tested over this larger data set, about five times the number of entries utilized by Kusnezov. Beyond a more detailed study of the dependence of the width on temperature and spin, the compiled data can be broken into subsets with common characteristics. By analyzing subsets of the data, we hope to gain a clearer understanding of the influence of shell effects, deformation, and gating conditions on the GDR width.[0mm] [1] D. Kusnezov et al., Phys. Rev. Lett. 81,42 (1998).[0mm] [2] A. Schiller and M. Thoennessen, nucl-ex/0605004.

  14. Characteristics of vibration energy harvesting using giant magnetostrictive cantilevers with resonant tuning

    NASA Astrophysics Data System (ADS)

    Mori, Kotaro; Horibe, Tadashi; Ishikawa, Shigekazu; Shindo, Yasuhide; Narita, Fumio

    2015-12-01

    This work deals with the dynamic bending and energy harvesting characteristics of giant magnetostrictive cantilevers with resonant tuning both numerically and experimentally. The giant magnetostrictive cantilever is fabricated using a thin Terfenol-D layer, SUS layer, movable proof mass, etc, and, is designed to automatically adjust its own resonant frequency to match the external vibration frequency in real time. Three-dimensional finite element analysis was conducted, and the resonant frequency, induced voltage and stress in the magnetostrictive cantilevers were predicted. The resonant frequency and induced voltage were also measured, and comparison was made between simulation and experiment. The time-varying behavior and self-tuning ability are discussed in detail.

  15. Attosecond delay of xenon 4 d photoionization at the giant resonance and Cooper minimum

    NASA Astrophysics Data System (ADS)

    Magrakvelidze, Maia; Madjet, Mohamed El-Amine; Chakraborty, Himadri S.

    2016-07-01

    A Kohn-Sham time-dependent local-density-functional scheme is utilized to predict attosecond time delays of xenon 4 d photoionization that involves the 4 d giant dipole resonance and Cooper minimum. The fundamental effect of electron correlations to uniquely determine the delay at both regions is demonstrated. In particular, for the giant dipole resonance, the delay underpins strong collective effect, emulating the recent prediction at C60 giant plasmon resonance [T. Barillot et al., Phys. Rev. A 91, 033413 (2015), 10.1103/PhysRevA.91.033413]. For the Cooper minimum, a qualitative similarity with a photorecombination experiment near argon 3 p minimum [S. B. Schoun et al., Phys. Rev. Lett. 112, 153001 (2014), 10.1103/PhysRevLett.112.153001] is found. The result should encourage attosecond measurements of Xe 4 d photoemission.

  16. Excitation and photon decay of giant multipole resonances - the role and future of medium-energy heavy ions

    SciTech Connect

    Bertrand, F.E.; Beene, J.R.; Horen, D.J.

    1988-01-01

    Inelastic scattering of medium energy heavy ions provides very large cross sections and peak-to-continuum ratios for excitation of giant resonances. For energies above about 50 MeV/nucleon, giant resonances are excited primarily through Coulomb excitation, which is indifferent to isospin, thus providing a good probe for the study of isovector giant resonances. The extremely large cross sections available from heavy ion excitation permit the study of rare decay modes of the photon decay of giant resonances following excitation by 22 and 84 MeV/nucleon /sup 17/O projectiles. The singles results at 84 MeV/nucleon yield peak cross sections for the isoscalar giant quadrupole resonance and the isovector giant dipole resonance of approximately 0.8 and 3 barns/sr, respectively. Data on the ground state decay of the isoscalar giant quadrupole and isovector giant dipole resonances are presented and compared with calculations. Decays to low-lying excited states are also discussed. Preliminary results from an experiment to isolate the /sup 208/Pb isovector quadrupole resonance using its gamma decay are presented.

  17. Relativistic effects on giant resonances in electron-impact double ionization

    SciTech Connect

    Pindzola, M.S.

    1987-06-01

    The electron-impact double-ionization cross section for Fr/sup +/ is calculated in the distorted-wave Born approximation. A giant resonance in the 5d subshell ionization-autoionization contribution to the cross section is found to be quite sensitive to changes in the double-well potential caused by relativistic effects on bound-state wave functions.

  18. The Isoscalar Giant Dipole Resonance in {sup 20}Pb, {sup 90}Zr and the Nuclear Compressibility

    SciTech Connect

    Yildirim, Serbulent; Koeroglu, Ulas

    2008-11-11

    The isoscalar giant dipol resonance (ISGDR) in finite nuclei is studied within the framework of a relativistic transport approach. The excitation energies of spherical {sup 90}Zr and {sup 208}Pb nuclei are obtained for different quantum hydrodynamical Lagrangian parametrization. The sensitivity of ISGDR excitation energy on the nuclear bulk to surface properties are also investigated.

  19. Pump-probe photoelectron velocity-map imaging of autoionizing singly excited 4s14p6np1(n=7,8) and doubly excited 4s24p45s16p1 resonances in atomic krypton

    NASA Astrophysics Data System (ADS)

    Doughty, Benjamin; Haber, Louis H.; Leone, Stephen R.

    2011-10-01

    Pump-probe photoelectron velocity-map imaging, using 27-eV high-harmonic excitation and 786-nm ionization, is used to resolve overlapping autoionizing resonances in atomic krypton, obtaining two-photon photoelectron angular distributions (PADs) for singly and doubly excited states. Two features in the photoelectron spectrum are assigned to singly excited 4s14p6np1 (n = 7,8) configurations and four features provide information about double excitation configurations. The anisotropy parameters for the singly excited 7p configuration are measured to be β2 = 1.61 ± 0.06 and β4 = 1.54 ± 0.16 while the 8p configuration gives β2 = 1.23 ± 0.19 and β4 = 0.60 ± 0.15. These anisotropies most likely represent the sum of overlapping PADs from states of singlet and triplet spin multiplicities. Of the four bands corresponding to ionization of doubly excited states, two are assigned to 4s24p45s16p1 configurations that are probed to different J-split ion states. The two remaining doubly excited states are attributed to a previously observed, but unassigned, resonance in the vacuum-ultraviolet photoabsorption spectrum. The PADs from each of the double excitation states are also influenced by overlap from neighboring states that are not completely spectrally resolved. The anisotropies of the observed double excitation states are reported, anticipating future theoretical and experimental work to separate the overlapping PADs into the state resolved PADs. The results can be used to test theories of excited state ionization.

  20. Coupled-Channel Models of Direct-Semidirect Capture via Giant-Dipole Resonances

    NASA Astrophysics Data System (ADS)

    Thompson, I. J.; Escher, J. E.; Arbanas, G.

    2014-04-01

    Semidirect capture, a two-step process that excites a giant-dipole resonance followed by its radiative de-excitation, is a dominant process near giant-dipole resonances, that is, for incoming neutron energies within 5-20 MeV. At lower energies such processes may affect neutron capture rates that are relevant to astrophysical nucleosynthesis models. We implement a semidirect capture model in the coupled-channel reaction code Fresco and validate it by comparing the cross section for direct-semidirect capture 208Pb(n,γ)209Pb to experimental data. We also investigate the effect of low-energy electric dipole strength in the pygmy resonance. We use a conventional single-particle direct-semidirect capture code Cupido for comparison. Furthermore, we present and discuss our results for direct-semidirect capture reaction 130Sn(n,γ)131Sn, the cross section of which is known to have a significant effect on nucleosynthesis models.

  1. Coupled-Channel Models of Direct-Semidirect Capture via Giant-Dipole Resonances

    SciTech Connect

    Thompson, I J; Escher, Jutta E; Arbanas, Goran

    2013-01-01

    Semidirect capture, a two-step process that excites a giant-dipole resonance followed by its radiative de-excitation, is a dominant process near giant-dipole resonances, that is, for incoming neutron energies within 5 20 MeV. At lower energies such processes may affect neutron capture rates that are relevant to astrophysical nucleosynthesis models. We implement a semidirect capture model in the coupled-channel reaction code Fresco and validate it by comparing the cross section for direct-semidirect capture 208Pb(n,g)209Pb to experimental data. We also investigate the effect of low-energy electric dipole strength in the pygmy resonance. We use a conventional single-particle direct-semidirect capture code Cupido for comparison. Furthermore, we present and discuss our results for direct-semidirect capture reaction 130Sn(n,g)131Sn, the cross section of which is known to have a significant effect on nucleosynthesis models.

  2. Splitting of the isovector giant dipole resonance in neutron-rich spherical nuclei

    SciTech Connect

    Kolomietz, V.M.; Magner, A.G.; Shlomo, S.

    2006-02-15

    The well-known splitting of the isovector giant dipole resonance is traditionally explained as a phenomenon of the nuclear isospin asymmetry (isospin splitting model) or the nuclear deformation. We suggest a new mechanism of the splitting of the giant multipole resonances in spherical neutron-rich nuclei resulting from the interplay of the isovector and isoscalar sounds with different velocities. Our approach is based on the collisional Landau kinetic theory and can be used for description of the splitting phenomena for both the isoscalar and the isovector modes in a wide region of nuclear masses A{approx}40-240. For the isovector dipole modes, the evaluated values of the splitting energy, the relative strength of the main and satellite resonance peaks, and the contribution to the energy-weighted sum rule are in agreement with experimental data.

  3. Isoscalar and isovector giant resonances in a self-consistent phonon coupling approach

    NASA Astrophysics Data System (ADS)

    Lyutorovich, N.; Tselyaev, V.; Speth, J.; Krewald, S.; Grümmer, F.; Reinhard, P.-G.

    2015-10-01

    We present fully self-consistent calculations of isoscalar giant monopole and quadrupole as well as isovector giant dipole resonances in heavy and light nuclei. The description is based on Skyrme energy-density functionals determining the static Hartree-Fock ground state and the excitation spectra within random-phase approximation (RPA) and RPA extended by including the quasiparticle-phonon coupling at the level of the time-blocking approximation (TBA). All matrix elements were derived consistently from the given energy-density functional and calculated without any approximation. As a new feature in these calculations, the single-particle continuum was included thus avoiding the artificial discretization usually implied in RPA and TBA. The step to include phonon coupling in TBA leads to small, but systematic, down shifts of the centroid energies of the giant resonances. These shifts are similar in size for all Skyrme parametrizations investigated here. After all, we demonstrate that one can find Skyrme parametrizations which deliver a good simultaneous reproduction of all three giant resonances within TBA.

  4. Giant spin Nernst effect induced by resonant scattering at surfaces of metallic films

    NASA Astrophysics Data System (ADS)

    Long, Nguyen H.; Mavropoulos, Phivos; Zimmermann, Bernd; Blügel, Stefan; Mokrousov, Yuriy

    2016-05-01

    A concept realizing giant spin Nernst effect in nonmagnetic metallic films is introduced. It is based on the idea of engineering an asymmetric energy dependence of the longitudinal and transverse electrical conductivities, as well as a pronounced energy dependence of the spin Hall angle in the vicinity of the Fermi level by the resonant impurity states at the Fermi level. We employ an analytical model and demonstrate the emergence of a giant spin Nernst effect in Ag(111) films using ab initio calculations combined with the Boltzmann approach for transport properties arising from skew scattering off impurities.

  5. Simplest photonuclear reactions accompanied by the excitation of isovector giant dipole and quadrupole resonances: Semimicroscopic description

    SciTech Connect

    Tulupov, B. A.; Urin, M. H.

    2012-09-15

    A semimicroscopic approach based on the continuum version of the random-phase approximation (CRPA) and on a semiphenomenological inclusion of the fragmentation effect is applied to describing cross sections for photoabsorption and direct plus semidirect and inverse reactions accompanied by the excitation of isovector giant dipole and quadrupole resonances. In addition to the spinless part of the Landau-Migdal interaction and a partly self-consistent phenomenological mean field of the nucleus, that version of the approach which is used here takes into account isovector separable velocity-dependent forces, as well as the effect of the fragmentation shift of the giant-resonance energy. The results obtained by calculating various features of the aforementioned cross sections for a number of magic and semimagic medium-mass nuclei are compared with respective experimental data.

  6. Damping Mechanism of the Giant Dipole Resonance in Hot Nuclei with A=130

    NASA Astrophysics Data System (ADS)

    Wieland, O.; Bracco, A.; Camera, F.; Benzoni, G.; Blasi, N.; Crespi, F. C. L.; Leoni, S.; Million, B.; Barlini, S.; Kravchuk, V. L.; Gramegna, F.; Lanchais, A.; Maj, A.; Kmiecik, M.; Casini, G.; Chiari, M.; Nannini, A.; Bruno, M.; Geraci, E.

    2007-04-01

    The gamma decay of the Giant Dipole Resonance (GDR) in 132Ce nuclei has been measured using the reactions 64Ni (Elab= 300, 400, 500 MeV) + 68Zn and 16O (Elab= 130,250 MeV) + 116Sn. The analysis of the data shows clearly that the GDR width increases steadily with temperature at least up to 4 MeV of the temperature. The data can be well interpreted within the thermal shape fluctuation model.

  7. Fluxes and spectra of quasimonochromatic annihilation photons for studying E1 giant resonances in nuclei

    SciTech Connect

    Dzhilavyan, L. Z.

    2014-12-15

    The fluxes and spectra of quasimonochromatic photons originating from the in-flight annihilation of positrons interacting with electrons of targets are analyzed in the energy region characteristic of the excitation of E1 giant resonances in nuclei. Targets of small thickness and low atomic number are used. The dependences of the spectra on the energy and angle (and their scatter) for positrons incident to the target, on the collimation angle for photons, and on the target thickness are studied.

  8. Giant Resonances in the Alpha-Nucleus Interaction

    SciTech Connect

    Karpeshin, F. F.

    2010-04-30

    Tunneling of alpha particles through the Coulomb barrier for the source {sup 135}Pr nucleus is consecutively considered. The effect of sharp peaks arising in the case of coincidence of the alpha energy with that of a quasistationary state within the barrier is elucidated. Peaks' energy depend on the alpha-nucleus potential. They can give rise to 'anomalous' properties of some neutron resonances. The peaks can also be observed in the incoming alpha-nucleus channel. The method can be applied for solution of the reverse problem of the alpha-nucleus scattering.

  9. On the orbital evolution of a pair of giant planets in mean motion resonance

    NASA Astrophysics Data System (ADS)

    André, Q.; Papaloizou, J. C. B.

    2016-10-01

    Pairs of extrasolar giant planets in a mean motion commensurability are common with 2:1 resonance occurring most frequently. Disc-planet interaction provides a mechanism for their origin. However, the time-scale on which this could operate in particular cases is unclear. We perform 2D and 3D numerical simulations of pairs of giant planets in a protoplanetary disc as they form and maintain a mean motion commensurability. We consider systems with current parameters similar to those of HD 155358, 24 Sextantis and HD 60532, and disc models of varying mass, decreasing mass corresponding to increasing age. For the lowest mass discs, systems with planets in the Jovian mass range migrate inwards maintaining a 2:1 commensurability. Systems with the inner planet currently at around 1 au from the central star could have originated at a few au and migrated inwards on a time-scale comparable to protoplanetary disc lifetimes. Systems of larger mass planets such as HD 60532 attain 3:1 resonance as observed. For a given mass accretion rate, results are insensitive to the disc model for the range of viscosity prescriptions adopted, there being good agreement between 2D and 3D simulations. However, in a higher mass disc a pair of Jovian mass planets passes through 2:1 resonance before attaining a temporary phase lasting a few thousand orbits in an unstable 5:3 resonance prior to undergoing a scattering. Thus, finding systems in this commensurability is unlikely.

  10. 'Coulomb' description of basic relaxation parameters of isobar analog and charge-exchange giant monopole resonances

    SciTech Connect

    Gorelik, M. L.; Rykovanov, V. S.; Urin, M. G.

    2010-12-15

    Within a semimicroscopic approach, basic relaxation parameters of the isobaric analog resonance and of the charge-exchange giant monopole resonance, which is an overtone of the isobaric analog resonance, are interpreted in terms of the mean Coulomb field of a nucleus. The continuum version of the random-phase approximation, allowance for an approximate isospin conservation in nuclei in an explicit form, and a phenomenological description of the fragmentation effect are basic ingredients of the approach used. The aforementioned parameters were calculated for a number of magic and near-magic nuclei by using a partly self-consistent phenomenological nuclear mean field and the isovector part of the Landau-Migdal interaction in the particle-hole channel. The results of the calculations are compared with corresponding experimental data.

  11. Making the Moon from a fast-spinning Earth: a giant impact followed by resonant despinning.

    PubMed

    Ćuk, Matija; Stewart, Sarah T

    2012-11-23

    A common origin for the Moon and Earth is required by their identical isotopic composition. However, simulations of the current giant impact hypothesis for Moon formation find that most lunar material originated from the impactor, which should have had a different isotopic signature. Previous Moon-formation studies assumed that the angular momentum after the impact was similar to that of the present day; however, Earth-mass planets are expected to have higher spin rates at the end of accretion. Here, we show that typical last giant impacts onto a fast-spinning proto-Earth can produce a Moon-forming disk derived primarily from Earth's mantle. Furthermore, we find that a faster-spinning early Earth-Moon system can lose angular momentum and reach the present state through an orbital resonance between the Sun and Moon. PMID:23076099

  12. Making the Moon from a fast-spinning Earth: a giant impact followed by resonant despinning.

    PubMed

    Ćuk, Matija; Stewart, Sarah T

    2012-11-23

    A common origin for the Moon and Earth is required by their identical isotopic composition. However, simulations of the current giant impact hypothesis for Moon formation find that most lunar material originated from the impactor, which should have had a different isotopic signature. Previous Moon-formation studies assumed that the angular momentum after the impact was similar to that of the present day; however, Earth-mass planets are expected to have higher spin rates at the end of accretion. Here, we show that typical last giant impacts onto a fast-spinning proto-Earth can produce a Moon-forming disk derived primarily from Earth's mantle. Furthermore, we find that a faster-spinning early Earth-Moon system can lose angular momentum and reach the present state through an orbital resonance between the Sun and Moon.

  13. The gamma decay of the giant dipole resonance: from zero to finite temperature

    NASA Astrophysics Data System (ADS)

    Bracco, Angela; Camera, Franco

    2016-08-01

    This paper is intended to give a selected and rather brief overview of the work made in the last thirty years to study the properties of the giant dipole resonance focusing in particular on nuclei formed at finite temperatures using heavy ion reactions. The physical problems that are discussed (using examples of particular results) in this paper can be grouped into 3 major topics: (i) the temperature dependence of the GDR width; (ii) the dipole oscillation in reaction dynamics; (iii) the isospin mixing at finite temperature.

  14. On the damping of giant resonances and the independent propagation of particles and holes

    NASA Astrophysics Data System (ADS)

    Alkofer, R.; Hofmann, H.; Siemens, P. J.

    1988-01-01

    In the literature, damping of nuclear collective motion has been attributed to the imaginary part of the self-energies of particles and holes, when assumed to move independently. We examine this picture within a schematic model adapted to the case of giant resonances. In this model we take degenerate 1p-1h states and dress them by a simple analytical form for the self-energies. We are able to calculate the intrinsic response function analytically and thus to study various approximations. We demonstrate that the on-shell approximation appreciably overestimates the widths of the collective vibrations.

  15. Giant Lipomatosis of the Sciatic Nerve: Unique Magnetic Resonance Imaging Findings.

    PubMed

    Sarp, Ali Firat; Pekcevik, Yeliz

    2016-04-01

    Lipomatosis of the nerve, also known as fibrolipomatous hamartoma, is characterized by the infiltration of the nerve by fibro-fatty tissue. The affected nerve becomes thicker, and it simulates a mass lesion. Lipomatosis usually affects the median nerve and lipomatosis of the sciatic nerve is extremely rare. Magnetic resonance imaging (MRI) is the key to diagnosis, and it is usually pathognomonic. In this report, MRI and diffusion-weighted MRI findings of a case of a giant sciatic nerve lipomatosis without macrodactyly are presented. The MRI findings are unique, and awareness of the MRI features of this rare soft tissue mass may prevent unnecessary biopsies and surgeries. PMID:27679695

  16. Giant Lipomatosis of the Sciatic Nerve: Unique Magnetic Resonance Imaging Findings

    PubMed Central

    Sarp, Ali Firat; Pekcevik, Yeliz

    2016-01-01

    Lipomatosis of the nerve, also known as fibrolipomatous hamartoma, is characterized by the infiltration of the nerve by fibro-fatty tissue. The affected nerve becomes thicker, and it simulates a mass lesion. Lipomatosis usually affects the median nerve and lipomatosis of the sciatic nerve is extremely rare. Magnetic resonance imaging (MRI) is the key to diagnosis, and it is usually pathognomonic. In this report, MRI and diffusion-weighted MRI findings of a case of a giant sciatic nerve lipomatosis without macrodactyly are presented. The MRI findings are unique, and awareness of the MRI features of this rare soft tissue mass may prevent unnecessary biopsies and surgeries.

  17. Giant Lipomatosis of the Sciatic Nerve: Unique Magnetic Resonance Imaging Findings

    PubMed Central

    Sarp, Ali Firat; Pekcevik, Yeliz

    2016-01-01

    Lipomatosis of the nerve, also known as fibrolipomatous hamartoma, is characterized by the infiltration of the nerve by fibro-fatty tissue. The affected nerve becomes thicker, and it simulates a mass lesion. Lipomatosis usually affects the median nerve and lipomatosis of the sciatic nerve is extremely rare. Magnetic resonance imaging (MRI) is the key to diagnosis, and it is usually pathognomonic. In this report, MRI and diffusion-weighted MRI findings of a case of a giant sciatic nerve lipomatosis without macrodactyly are presented. The MRI findings are unique, and awareness of the MRI features of this rare soft tissue mass may prevent unnecessary biopsies and surgeries. PMID:27679695

  18. Resonant excitation of black holes by massive bosonic fields and giant ringings

    NASA Astrophysics Data System (ADS)

    Décanini, Yves; Folacci, Antoine; Ould El Hadj, Mohamed

    2014-04-01

    We consider the massive scalar field, the Proca field, and the Fierz-Pauli field in the Schwarzschild spacetime and we focus more particularly on their long-lived quasinormal modes. We show numerically that the associated excitation factors have a strong resonant behavior and we confirm this result analytically from semiclassical considerations based on the properties of the unstable circular geodesics on which a massive particle can orbit the black hole. The conspiracy of (i) the long-lived behavior of the quasinormal modes and (ii) the resonant behavior of their excitation factors induces intrinsic giant ringings, i.e., ringings of a huge amplitude. Such ringings, which are moreover slowly decaying, are directly constructed from the retarded Green function. If we describe the source of the black hole perturbation by an initial value problem with Gaussian initial data, i.e., if we consider the excitation of the black hole from an extrinsic point of view, we can show that these extraordinary ringings are still present. This suggests that physically realistic sources of perturbations should generate giant and slowly decaying ringings and that their existence could be used to constrain ultralight bosonic field theory interacting with black holes.

  19. Photodisintegration of heavy nuclei in the energy region above the giant dipole resonance

    SciTech Connect

    Ermakov, A. N.; Ishkhanov, B. S.; Kapitonov, I. M.; Makarenko, I. V. Orlin, V. N.

    2010-05-15

    Experimental data on yields of multiparticle photonuclear reactions (involving the emission of up to seven neutrons from the nucleus involved) on {sup 197}Au, {sup 203,205}Tl, and {sup 209}Bi nuclei in the region extending from the giant dipole resonance to an energy of 67.7 MeV are presented. These data are compared with the results of modern theoretical calculations that take into account both the excitation of a giant dipole resonance (GDR) in a nucleus and the photodisintegration of quasideutrons (QD) in it. By and large, experimental data confirm the results of theoretical calculations-that is, only upon taking simultaneously into account both alternative photodisintegration mechanisms (GDR excitation and QD photodisintegration) can one describe these experimental data. The contribution of QD photodisintegration grows with increasing photon energy and neutron multiplicity and becomes dominant for reactions involving the emission of not less than five neutrons from the nucleus being considered. The integrated cross sections for the processes in question were estimated on the basis of simultaneously employing experimental yields of multinucleon photonuclear reactions and the respective cross-section shapes calculated theoretically.

  20. Dynamics of the [4Fe-4S] Cluster in Pyrococcus furiosus D14C Ferredoxin via Nuclear Resonance Vibrational and Resonance Raman Spectroscopies, Force Field Simulations, and Density Functional Theory Calculations

    PubMed Central

    Mitra, Devrani; Pelmenschikov, Vladimir; Guo, Yisong; Case, David A.; Wang, Hongxin; Dong, Weibing; Tan, Ming-Liang; Ichiye, Toshiko; Jenney, Francis E.; Adams, Michael W. W.; Yoda, Yoshitaka; Zhao, Jiyong; Cramer, Stephen P.

    2011-01-01

    We have used 57Fe nuclear resonance vibrational spectroscopy (NRVS) to study oxidized and reduced forms of the [4Fe-4S] cluster in the D14C variant ferredoxin from Pyrococcus furiosus (Pf D14C Fd). To assist the normal mode assignments, we recorded the NRVS of D14C ferredoxin samples with 36S substituted into the [4Fe-4S] cluster bridging sulfide positions, and a model compound without ligand side chains: (Ph4P)2[Fe4S4Cl4]. Several distinct regions of NRVS intensity are identified, ranging from `protein' and torsional modes below 100 cm−1, through bending and breathing modes near 150 cm−1, to strong bands from Fe-S stretching modes between 250 cm−1 and ~400 cm−1. The oxidized ferredoxin samples were also investigated by resonance Raman (RR) spectroscopy. We found good agreement between NRVS and RR frequencies, but because of different selection rules, the intensities vary dramatically between the two types of spectra. The 57Fe partial vibrational densities of states (PVDOS) for the oxidized samples were interpreted by normal mode analysis with optimization of Urey-Bradley force fields for local models of the [4Fe-4S] clusters. Full protein model calculations were also conducted using a supplemented CHARMM force field, and these calculations revealed low frequency modes that may be relevant to electron transfer with Pf Fd partners. Density functional theory (DFT) calculations complemented these empirical analyses, and DFT was used to estimate the reorganization energy associated with the [Fe4S4]2+/1+ redox cycle. Overall, the NRVS technique demonstrates great promise for the observation and quantitative interpretation of the dynamical properties of Fe-S proteins. PMID:21500788

  1. Giant thermo-optical relaxation oscillations in millimeter-size whispering gallery mode disk resonators.

    PubMed

    Diallo, Souleymane; Lin, Guoping; Chembo, Yanne K

    2015-08-15

    In this Letter, we show that giant thermo-optical oscillations can be triggered in millimeter (mm)-size whispering gallery mode (WGM) disk resonators when they are pumped by a resonant continuous-wave laser. Our resonator is an ultrahigh-Q barium fluoride cavity that features a positive thermo-optic coefficient and a negative thermo-elastic coefficient. We demonstrate for the first time, to our knowledge, that the complex interplay between these two thermic coefficients and the intrinsic Kerr nonlinearity yields very sharp slow-fast relaxation oscillations with a slow timescale that can be exceptionally large, typically of the order of 1 s. We use a time-domain model to gain understanding into this instability, and we find that both the experimental and theoretical results are in excellent agreement. The understanding of these thermal effects is an essential requirement for every WGM-related application and our study demonstrates that even in the case of mm-size resonators, such effects can still be accurately analyzed using nonlinear time-domain models.

  2. Cardiac Sarcoidosis or Giant Cell Myocarditis? On Treatment Improvement of Fulminant Myocarditis as Demonstrated by Cardiovascular Magnetic Resonance Imaging

    PubMed Central

    Bogabathina, Hari; Olson, Peter; Rathi, Vikas K.; Biederman, Robert W. W.

    2012-01-01

    Giant cell myocarditis, but not cardiac sarcoidosis, is known to cause fulminant myocarditis resulting in severe heart failure. However, giant cell myocarditis and cardiac sarcoidosis are pathologically similar, and attempts at pathological differentiation between the two remain difficult. We are presenting a case of fulminant myocarditis that has pathological features suggestive of cardiac sarcoidosis, but clinically mimicking giant cell myocarditis. This patient was treated with cyclosporine and prednisone and recovered well. This case we believe challenges our current understanding of these intertwined conditions. By obtaining a sense of severity of cardiac involvement via delayed hyperenhancement of cardiac magnetic resonance imaging, we were more inclined to treat this patient as giant cell myocarditis with cyclosporine. This resulted in excellent improvement of patient's cardiac function as shown by delayed hyperenhancement images, early perfusion images, and SSFP videos. PMID:24826266

  3. Plasmonic coupled modes in metal-dielectric multilayer structures: Fano resonance and giant field enhancement.

    PubMed

    Sekkat, Zouheir; Hayashi, Shinji; Nesterenko, Dmitry V; Rahmouni, Anouar; Refki, Siham; Ishitobi, Hidekazu; Inouye, Yasushi; Kawata, Satoshi

    2016-09-01

    We provide an overview of Fano resonance and plasmon induced transparency (PIT) as well as on plasmons coupling in planar structures, and we discuss their application in sensing and enhanced spectroscopy. Metal-insulator-metal (MIM) structures, which are known to support symmetric and anti-symmetric surface plasmon polaritons (SPPs) arising from the coupling between two SPPs at the metal-insulator interfaces, exhibit anticrossing behavior of the dispersion relations arising from the coupling of the symmetric SPP and the metal/air SPP. Multilayer structures, formed by a metal film and a high-index dielectric waveguide (WG), separated by a low-index dielectric spacer layer, give narrow resonances of PIT and Fano line shapes. An optimized Fano structure shows a giant field intensity enhancement value of 106 in air at the surface of the high-index dielectric WG. The calculated field enhancement factor and the figure of merit for the sensitivity of the Fano structure in air can be 104 times as large as those of the conventional surface plasmon resonance and WG sensors. PMID:27607617

  4. Plasmonic coupled modes in metal-dielectric multilayer structures: Fano resonance and giant field enhancement.

    PubMed

    Sekkat, Zouheir; Hayashi, Shinji; Nesterenko, Dmitry V; Rahmouni, Anouar; Refki, Siham; Ishitobi, Hidekazu; Inouye, Yasushi; Kawata, Satoshi

    2016-09-01

    We provide an overview of Fano resonance and plasmon induced transparency (PIT) as well as on plasmons coupling in planar structures, and we discuss their application in sensing and enhanced spectroscopy. Metal-insulator-metal (MIM) structures, which are known to support symmetric and anti-symmetric surface plasmon polaritons (SPPs) arising from the coupling between two SPPs at the metal-insulator interfaces, exhibit anticrossing behavior of the dispersion relations arising from the coupling of the symmetric SPP and the metal/air SPP. Multilayer structures, formed by a metal film and a high-index dielectric waveguide (WG), separated by a low-index dielectric spacer layer, give narrow resonances of PIT and Fano line shapes. An optimized Fano structure shows a giant field intensity enhancement value of 106 in air at the surface of the high-index dielectric WG. The calculated field enhancement factor and the figure of merit for the sensitivity of the Fano structure in air can be 104 times as large as those of the conventional surface plasmon resonance and WG sensors.

  5. SP(6,R) Symmetry and the Giant Quadrupole Resonance in MAGNESIUM-24.

    NASA Astrophysics Data System (ADS)

    Reske, Edward John

    1984-06-01

    Microscopic nuclear calculations are approached by partitioning the many-nucleon Hilbert space as a direct sum of symplectic bands. Computational techniques and algorithms which utilize commutator methods, and which are more powerful than the more straight-forward purely shell-model approach, are developed for calculating the matrix elements of two-body operators within such an Sp(6,R) (R-HOOK) U(3) symmetry-adapted basis. These techniques may be generalized to n-body operators of any n. These computational tools are applied to the study of the Giant Quadrupole Resonance in ('24)Mg: the final calculation presented uses a microscopic Hamiltonian consisting of the kinetic energy plus the semi-realistic two-body Brink -Boeker B1 potential within a space consisting of three symplectic bands up to 6(H/2PI)(omega) total excitation.

  6. Measurement of isospin mixing at a finite temperature in 80Zr via giant dipole resonance decay

    NASA Astrophysics Data System (ADS)

    Corsi, A.; Wieland, O.; Barlini, S.; Bracco, A.; Camera, F.; Kravchuk, V. L.; Baiocco, G.; Bardelli, L.; Benzoni, G.; Bini, M.; Blasi, N.; Brambilla, S.; Bruno, M.; Casini, G.; Ciemala, M.; Cinausero, M.; Crespi, F. C. L.; D'Agostino, M.; Degerlier, M.; Giaz, A.; Gramegna, F.; Kmiecik, M.; Leoni, S.; Maj, A.; Marchi, T.; Mazurek, K.; Meczynski, W.; Million, B.; Montanari, D.; Morelli, L.; Myalski, S.; Nannini, A.; Nicolini, R.; Pasquali, G.; Poggi, G.; Vandone, V.; Vannini, G.

    2011-10-01

    Isospin mixing in the hot compound nucleus 80Zr was studied by measuring and comparing the γ-ray emission from the fusion reactions 40Ca+40Ca at Ebeam=200 MeV and 37Cl+44Ca at Ebeam=153 MeV. The γ yield associated with the giant dipole resonance is found to be different in the two reactions because, in self-conjugate nuclei, the E1 selection rules forbid the decay between states with isospin I=0. The degree of mixing is deduced from statistical-model analysis of the γ-ray spectrum emitted by the compound nucleus 80Zr with the standard parameters deduced from the γ decay of the nucleus 81Rb. The results are used to deduce the zero-temperature value, which is then compared with the latest predictions. The Coulomb spreading width is found to be independent of temperature.

  7. Fine structure of the isoscalar giant quadrupole resonance in 28Si and 27Al

    NASA Astrophysics Data System (ADS)

    Usman, I. T.; Buthelezi, Z.; Carter, J.; Cooper, G. R. J.; Fearick, R. W.; Förtsch, S. V.; Fujita, H.; Fujita, Y.; von Neumann-Cosel, P.; Neveling, R.; Papakonstantinou, P.; Pysmenetska, I.; Richter, A.; Roth, R.; Sideras-Haddad, E.; Smit, F. D.

    2016-08-01

    The isoscalar giant quadrupole resonance in 28Si and 27Al has been investigated with high-energy-resolution proton inelastic scattering at Ep=200 MeV and at scattering angles close to the maximum of Δ L =2 angular distributions with the K600 magnetic spectrometer of iThemba LABS, South Africa. Characteristic scales are extracted from the observed fine structure with a wavelet analysis and compared for 28Si with random-phase approximation and second random phase approximation calculations with an interaction derived from the Argonne V18 potential by a unitary transformation. A recent extension of the method to deformed nuclei provides the best description of the data, suggesting the significance of Landau damping.

  8. Neutron-skin thickness from the study of the anti-analog giant dipole resonance

    SciTech Connect

    Krasznahorkay, A.; Stuhl, L.; Csatlos, M.; Algora, A.; and others

    2012-10-20

    The {gamma}-decay of the anti-analog of the giant dipole resonance (AGDR) to the isobaric analog state has been measured following the p({sup 124}Sn,n) reaction at a beam energy of 600 MeV/nucleon. The energy of the transition was also calculated with state-of-the-art self-consistent relativistic random-phase approximation (RPA) and turned out to be very sensitive to the neutronskin thickness ({Delta}R{sub pn}). By comparing the theoretical results with the measured one, the {Delta}R{sub pn} value for {sup 124}Sn was deduced to be 0.21 {+-} 0.07 fm, which agrees well with the previous results. The present method offers new possibilities for measuring the neutron-skin thicknesses of very exotic isotopes.

  9. Fluctuation properties of the strength function associated with the giant quadrupole resonance in {sup 208}Pb

    SciTech Connect

    Aiba, Hirokazu; Matsuo, Masayuki; Nishizaki, Shigeru; Suzuki, Toru

    2011-02-15

    We performed fluctuation analysis by means of the local scaling dimension for the strength function of the isoscalar (IS) giant quadrupole resonance (GQR) in {sup 208}Pb where the strength function is obtained by the shell model calculation including 1p1h and 2p2h configurations. It is found that at almost all energy scales, fluctuation of the strength function obeys the Gaussian orthogonal ensemble (GOE) random matrix theory limit. This is contrasted with the results for the GQR in {sup 40}Ca, where at the intermediate energy scale of about 1.7 MeV, a deviation from the GOE limit was detected. It is found that the physical origin for this different behavior of the local scaling dimension is ascribed to the difference in the properties of the damping process.

  10. Study of Isoscalar Giant Resonances in Exotic Nuclei by Means of Inverse Reactions

    NASA Astrophysics Data System (ADS)

    Harakeh, M. N.

    2015-11-01

    Isoscalar giant resonances in exotic nuclei can be studied using inelastic alpha scattering in inverse kinematics. In particular, the compression modes, i.e. isoscalar giant monopole and dipole resonances, are very interesting because they can furnish information on the different terms of the nuclear incompressibility, especially if measured in long isotopic chains including nuclei far from the valley of stability. As beams of exotic nuclei have relatively low intensities thick targets have to be used in order to get a reasonable yield. However, this leads to degradation of the energy resolution and stops low-energy recoil particles. Two good alternatives exist. The first method is to use an active target, such as MAYA, which is a time-projection chamber and therefore can be used for detection of low-energy recoil particles. Furthermore, its thickness can be increased by increasing the length of the detection volume or the gas pressure without severe loss of energy resolution. The second method is to use a storage ring for storing the exotic nuclei, which then interact with target nuclei from a gas-jet target. Here, the luminosity and hence the yield are increased because the exotic nuclei circulate in the ring at a frequency of around 106 turns/s. Low-energy recoil particles traverse the gas-jet with little loss of energy and can be detected in solid-state detectors. Pioneering experiments with both methods have been performed for inelastic scattering of secondary 56Ni beam off helium nuclei. Here, preliminary results of the experiment with the active target MAYA will be presented.

  11. Self-consistent separable random-phase approximation for Skyrme forces: Giant resonances in axial nuclei

    SciTech Connect

    Nesterenko, V. O.; Dolci, D. S.; Kleinig, W.; Kvasil, J.; Vesely, P.; Reinhard, P.-G.

    2006-12-15

    We formulate the self-consistent separable random phase approximation (SRPA) method and specify it for Skyrme forces with pairing for the case of axially symmetric deformed nuclei. The factorization of the residual interaction allows diagonalization of high-ranking RPA matrices to be avoided, which dramatically reduces the computational expense. This advantage is crucial for the systems with a huge configuration space, first of all for deformed nuclei. SRPA self-consistently takes into account the contributions of both time-even and time-odd Skyrme terms as well as of the Coulomb force and pairing. The method is implemented to describe isovector E1 and isoscalar E2 giant resonances in a representative set of deformed nuclei: {sup 154}Sm, {sup 238}U, and {sup 254}No. Four different Skyrme parameterizations (SkT6, SkM*, SLy6, and SkI3) are employed to explore the dependence of the strength distributions on some basic characteristics of the Skyrme functional and nuclear matter. In particular, we discuss the role of isoscalar and isovector effective masses and their relation to time-odd contributions. The high sensitivity of the right flank of E1 resonance to different Skyrme forces and the related artificial structure effects are analyzed.

  12. Extremely narrow resonances, giant sensitivity and field enhancement in low-loss waveguide sensors

    NASA Astrophysics Data System (ADS)

    Nesterenko, D. V.; Hayashi, S.; Sekkat, Z.

    2016-06-01

    Low-loss waveguides (WGs), which support excitation of waveguide modes (WMs), are based on a dielectric WG separated from an absorptive film by a low-index dielectric spacer layer. We perform numerical and analytical study of the impact of the losses imposed to the WG in a planar sensing structure in the Kretschmann configuration on the resonance properties of the excitation. We demonstrate that the loss degree of the WMs can be controlled by the thickness of the spacer layer for both s and p polarizations. Extremely narrow resonances are discovered in the reflectivity spectra due to excitation of the low-loss WMs, and the maximum of the estimated sensitivity by intensity is found to be of 105-fold higher as compared to the conventional surface plasmon and WG-coupled surface plasmon sensors. We reveal the giant field intensity enhancement of 107-fold on the surface of the sensing structure in aqueous sensing media that can provide stronger fluorescence intensity at lower sample volumes for fluorescent labeling sensing.

  13. Giant resonances in {sup 238}U within the quasiparticle random-phase approximation with the Gogny force

    SciTech Connect

    Peru, S.; Gosselin, G.; Martini, M.; Dupuis, M.; Hilaire, S.

    2011-01-15

    Fully consistent axially-symmetric deformed quasiparticle random-phase approximation (QRPA) calculations have been performed, using the same Gogny D1S effective force for both the Hartree-Fock-Bogolyubov mean field and QRPA matrix. New implementation of this approach leads to the applicability of QRPA to heavy deformed nuclei. Giant resonances and low-energy collective states for monopole, dipole, quadrupole, and octupole modes are predicted for the heavy deformed nucleus {sup 238}U and compared with experimental data.

  14. TERRESTRIAL PLANET FORMATION DURING THE MIGRATION AND RESONANCE CROSSINGS OF THE GIANT PLANETS

    SciTech Connect

    Lykawka, Patryk Sofia; Ito, Takashi

    2013-08-10

    The newly formed giant planets may have migrated and crossed a number of mutual mean motion resonances (MMRs) when smaller objects (embryos) were accreting to form the terrestrial planets in the planetesimal disk. We investigated the effects of the planetesimal-driven migration of Jupiter and Saturn, and the influence of their mutual 1:2 MMR crossing on terrestrial planet formation for the first time, by performing N-body simulations. These simulations considered distinct timescales of MMR crossing and planet migration. In total, 68 high-resolution simulation runs using 2000 disk planetesimals were performed, which was a significant improvement on previously published results. Even when the effects of the 1:2 MMR crossing and planet migration were included in the system, Venus and Earth analogs (considering both orbits and masses) successfully formed in several runs. In addition, we found that the orbits of planetesimals beyond a {approx} 1.5-2 AU were dynamically depleted by the strengthened sweeping secular resonances associated with Jupiter's and Saturn's more eccentric orbits (relative to the present day) during planet migration. However, this depletion did not prevent the formation of massive Mars analogs (planets with more than 1.5 times Mars's mass). Although late MMR crossings (at t > 30 Myr) could remove such planets, Mars-like small mass planets survived on overly excited orbits (high e and/or i), or were completely lost in these systems. We conclude that the orbital migration and crossing of the mutual 1:2 MMR of Jupiter and Saturn are unlikely to provide suitable orbital conditions for the formation of solar system terrestrial planets. This suggests that to explain Mars's small mass and the absence of other planets between Mars and Jupiter, the outer asteroid belt must have suffered a severe depletion due to interactions with Jupiter/Saturn, or by an alternative mechanism (e.g., rogue super-Earths)

  15. Terrestrial Planet Formation during the Migration and Resonance Crossings of the Giant Planets

    NASA Astrophysics Data System (ADS)

    Lykawka, Patryk Sofia; Ito, Takashi

    2013-08-01

    The newly formed giant planets may have migrated and crossed a number of mutual mean motion resonances (MMRs) when smaller objects (embryos) were accreting to form the terrestrial planets in the planetesimal disk. We investigated the effects of the planetesimal-driven migration of Jupiter and Saturn, and the influence of their mutual 1:2 MMR crossing on terrestrial planet formation for the first time, by performing N-body simulations. These simulations considered distinct timescales of MMR crossing and planet migration. In total, 68 high-resolution simulation runs using 2000 disk planetesimals were performed, which was a significant improvement on previously published results. Even when the effects of the 1:2 MMR crossing and planet migration were included in the system, Venus and Earth analogs (considering both orbits and masses) successfully formed in several runs. In addition, we found that the orbits of planetesimals beyond a ~ 1.5-2 AU were dynamically depleted by the strengthened sweeping secular resonances associated with Jupiter's and Saturn's more eccentric orbits (relative to the present day) during planet migration. However, this depletion did not prevent the formation of massive Mars analogs (planets with more than 1.5 times Mars's mass). Although late MMR crossings (at t > 30 Myr) could remove such planets, Mars-like small mass planets survived on overly excited orbits (high e and/or i), or were completely lost in these systems. We conclude that the orbital migration and crossing of the mutual 1:2 MMR of Jupiter and Saturn are unlikely to provide suitable orbital conditions for the formation of solar system terrestrial planets. This suggests that to explain Mars's small mass and the absence of other planets between Mars and Jupiter, the outer asteroid belt must have suffered a severe depletion due to interactions with Jupiter/Saturn, or by an alternative mechanism (e.g., rogue super-Earths).

  16. Terrestrial Planet Formation During the Migration and Resonance Crossings of the Giant Planets

    NASA Astrophysics Data System (ADS)

    Lykawka, Patryk S.; Ito, T.

    2013-10-01

    The newly formed giant planets may have migrated and crossed a number of mutual mean motion resonances (MMRs) when smaller objects (embryos) were accreting to form the terrestrial planets in the planetesimal disk. We investigated the effects of the planetesimal-driven migration of Jupiter and Saturn, and the influence of their mutual 1:2 MMR crossing on terrestrial planet formation for the first time, by performing N-body simulations. These simulations considered distinct timescales of MMR crossing and planet migration. In total, 68 high-resolution simulation runs using 2000 disk planetesimals were performed, which was a significant improvement on previously published results. Even when the effects of the 1:2 MMR crossing and planet migration were included in the system, Venus and Earth analogs (considering both orbits and masses) successfully formed in several runs. In addition, we found that the orbits of planetesimals beyond a ~1.5-2 AU were dynamically depleted by the strengthened sweeping secular resonances associated with Jupiter’s and Saturn’s more eccentric orbits (relative to present-day) during planet migration. However, this depletion did not prevent the formation of massive Mars analogs (planets with more than 1.5 times Mars’ mass). Although late MMR crossings (at t > 30 Myr) could remove such planets, Mars-like small mass planets survived on overly excited orbits (high e and/or i), or were completely lost in these systems. We conclude that the orbital migration and crossing of the mutual 1:2 MMR of Jupiter and Saturn are unlikely to provide suitable orbital conditions for the formation of solar system terrestrial planets. This suggests that to explain Mars’ small mass and the absence of other planets between Mars and Jupiter, the outer asteroid belt must have suffered a severe depletion due to interactions with Jupiter/Saturn, or by an alternative mechanism (e.g., rogue super-Earths).

  17. Extreme nuclear shapes examined via giant dipole resonance lineshapes in hot light-mass systems

    SciTech Connect

    Pandit, Deepak; Mukhopadhyay, S.; Pal, Surajit; Bhattacharya, S.; Bhattacharya, C.; Banerjee, K.; Kundu, S.; Rana, T. K.; Dey, A.; Mukherjee, G.; Ghosh, T.; Banerjee, S. R.; De, A.; Gupta, D.

    2010-06-15

    The influence of alpha clustering on nuclear reaction dynamics is investigated using the giant dipole resonance (GDR) lineshape studies in the reactions {sup 20}Ne (E{sub lab}=145,160 MeV) + {sup 12}C and {sup 20}Ne (E{sub lab}=160 MeV) + {sup 27}Al, populating {sup 32}S and {sup 47}V, respectively. The GDR lineshapes from the two systems are remarkably different from each other. Whereas, the non-alpha-like {sup 47}V undergoes Jacobi shape transition and matches exceptionally well with the theoretical GDR lineshape estimated under the framework rotating liquid drop model (RLDM) and thermal shape fluctuation model (TSFM) signifying shape equilibration, for the alpha cluster {sup 32}S an extended prolate kind of shape is observed. This unusual deformation, seen directly via gamma decay for the first time, is predicted to be due to the formation of orbiting dinuclear configuration or molecular structure of {sup 16}O + {sup 16}O in the {sup 32}S superdeformed band.

  18. Giant dipole resonance width in nuclei near Sn at low temperature and high angular momentum

    SciTech Connect

    Bhattacharya, Srijit; Mukhopadhyay, S.; Pandit, Deepak; Pal, Surajit; Bhattacharya, S.; Bhattacharya, C.; Banerjee, K.; Kundu, S.; Rana, T. K.; Dey, A.; Mukherjee, G.; Ghosh, T.; Gupta, D.; Banerjee, S. R.

    2008-02-15

    High energy {gamma} rays in coincidence with low energy yrast {gamma} rays have been measured from {sup 113}Sb, at excitation energies of 109 and 122 MeV, formed by bombarding {sup 20}Ne on {sup 93}Nb at projectile energies of 145 and 160 MeV, respectively, to study the role of angular momentum (J) and temperature (T) over giant dipole resonance (GDR) width ({gamma}). The maximum populated angular momenta for fusion were 67({Dirac_h}/2{pi}) and 73({Dirac_h}/2{pi}), respectively, for the above-mentioned beam energies. The high energy photons were detected using a Large Area Modular BaF{sub 2} Detector Array (LAMBDA) along with a 24-element multiplicity filter. After pre-equilibrium corrections, the excitation energy E* was averaged over the decay steps of the compound nucleus (CN). The average values of temperature, angular momentum, CN mass, etc., have been calculated using the statistical model code CASCADE. Using those average values, results show the systematic increase of GDR width with T, which is consistent with Kusnezov parametrization and the thermal shape fluctuation model (TSFM). The rise of GDR width with temperature also supports the assumptions of adiabatic coupling in the TSFM. But the GDR widths and corresponding reduced plots with J are not consistent with those of the theoretical model at high spins.

  19. The temperature dependence of the width of the giant dipole resonance

    SciTech Connect

    Ormand, W.E. |; Bortignon, P.F. |; Broglia, R.A. ||

    1995-12-31

    A systematic study of the full-width-at-half-maximum (FWHM) of the giant-dipole resonance (GDR) as a function of temperature for the nuclei {sup 120}Sn and {sup 208}Pb confirms the overall theoretical picture of the GDR in hot nuclei; in particular, the role played by large-amplitude thermal fluctuations of the nuclear shape. This is confirmed by the good agreement between theory and experiment achieved over a range of temperatures from 1.25--32 MeV and by the differences in the behavior of the FWHM for {sup 120}Sn and {sup 208}Pb, which can be attributed to the presence of strong shell corrections favoring spherical shapes in {sup 208}Pb that are absent in {sup 120}Sn. Finally, the increase in the FWHM over that expected from thermal averaging at temperatures of the order 3.0 MeV is in accordance with the increase expected from the particle evaporation of the compound system.

  20. Temperature dependence of the giant dipole resonance width in 152Gd

    NASA Astrophysics Data System (ADS)

    Ghosh, C.; Mishra, G.; Rhine Kumar, A. K.; Dokania, N.; Nanal, V.; Pillay, R. G.; Kumar, Suresh; Rout, P. C.; Joshi, Sandeep; Arumugam, P.

    2016-07-01

    To investigate the dependence of giant dipole resonance (GDR) width on temperature (T ) and angular momentum (J ), high energy γ -ray spectra were measured in the reaction 28Si+124Sn at E28Si=135 MeV. The J information was deduced from multiplicity of low-energy γ rays. The GDR parameters, namely, the centroid energy and width are extracted using statistical model analysis. The observed variation of the GDR width for T ˜1.2 -1.37 MeV and J ˜20 ℏ -40 ℏ is consistent with the universal scaling given by Kusnezov et al., which is applicable in the liquid-drop regime. The GDR input cross sections extracted from the statistical model best fits are compared with thermal shape fluctuation model (TSFM) calculations and are found to be in good agreement. The TSFM calculations predominantly favor the noncollective oblate shape, while the statistical model fit with both prolate and oblate shapes describes the data. The present data together with earlier measurements indicate a very slow variation of the GDR width for T ˜1.2 to 1.5 MeV. The observed trend is well explained by the TSFM calculations, although the calculated values are ˜4 %-13% higher than the data.

  1. Thermal shape fluctuation model study of the giant dipole resonance in 152Gd

    NASA Astrophysics Data System (ADS)

    Rhine Kumar, A. K.; Arumugam, P.

    2015-10-01

    We have studied the giant dipole resonance (GDR) in the hot and rotating nucleus 152Gd within the framework of the thermal shape fluctuation model (TSFM) built on the microscopic-macroscopic calculations of the free energies with a macroscopic approach for the GDR. Our results for GDR cross sections are in good agreement with the experimental values except for a component peaking around 17 MeV, where the data has large uncertainties. Such a component is beyond our description which properly takes care of the splitting of GDR components due to the deformation and Coriolis effects. Around 17 MeV lies the half maximum in experimental cross sections, and hence the extracted GDR widths and deformations (estimated from these widths) turn out to be overestimated and less reliable. Reproducing these widths with empirical formulas could conceal the information contained in the cross sections. Fully microscopic GDR calculations and a more careful look at the data could be useful to understand the GDR component around 17 MeV. We also discuss the occurrence of γ softness in the free energy surfaces of 152Gd and its role on GDR.

  2. Experimental study of playback giant magnetic resonance head nonlinearity in perpendicular recording

    NASA Astrophysics Data System (ADS)

    Luo, P.; Stoev, K.; Liu, F.; Vadde, A.; Gibbons, M.; Lederman, M.; Re, M.

    2003-05-01

    In this article, nonlinear distortions of the playback giant magnetic resonance (GMR) sensor in perpendicular recording are characterized in both time and frequency domains. We use three perpendicular media with different Mrt (0.46, 0.6, and 0.8 emu/cm2) and two groups of similar magnetic-read width (MRW) but different junction type [contiguous junction (CJ) and lead-over-lay (LOL)] GMR heads. Square-wave patterns at moderate densities are recorded to minimize NLTS, partial erasure, and transition broadening effects. Both time- and frequency-domain measurements indicate that the LOL-type GMR heads show playback nonlinearity (7%-23%), while the CJ-type GMR heads do not. Micromagnetic simulation is utilized to understand the hard bias field with different junction designs. The result indicates that the hard bias (HB) field in LOL type (HB field ˜6.9 Oe) at the air bearing surface (ABS) and stripe center is much lower than that in CJ type (HB field ˜54.0 Oe). Therefore, the free layer with large HB-HB distance will be more susceptible to saturation.

  3. Finite amplitude method applied to the giant dipole resonance in heavy rare-earth nuclei

    NASA Astrophysics Data System (ADS)

    Oishi, Tomohiro; Kortelainen, Markus; Hinohara, Nobuo

    2016-03-01

    Background: The quasiparticle random phase approximation (QRPA), within the framework of nuclear density functional theory (DFT), has been a standard tool to access the collective excitations of atomic nuclei. Recently, the finite amplitude method (FAM) was developed in order to perform the QRPA calculations efficiently without any truncation on the two-quasiparticle model space. Purpose: We discuss the nuclear giant dipole resonance (GDR) in heavy rare-earth isotopes, for which the conventional matrix diagonalization of the QRPA is numerically demanding. A role of the Thomas-Reiche-Kuhn (TRK) sum rule enhancement factor, connected to the isovector effective mass, is also investigated. Methods: The electric dipole photoabsorption cross section was calculated within a parallelized FAM-QRPA scheme. We employed the Skyrme energy density functional self-consistently in the DFT calculation for the ground states and FAM-QRPA calculation for the excitations. Results: The mean GDR frequency and width are mostly reproduced with the FAM-QRPA, when compared to experimental data, although some deficiency is observed with isotopes heavier than erbium. A role of the TRK enhancement factor in actual GDR strength is clearly shown: its increment leads to a shift of the GDR strength to higher-energy region, without a significant change in the transition amplitudes. Conclusions: The newly developed FAM-QRPA scheme shows remarkable efficiency, which enables one to perform systematic analysis of GDR for heavy rare-earth nuclei. The theoretical deficiency of the photoabsorption cross section could not be improved by only adjusting the TRK enhancement factor, suggesting the necessity of an approach beyond self-consistent QRPA and/or a more systematic optimization of the energy density functional (EDF) parameters.

  4. Global investigation of the fine structure of the isoscalar giant quadrupole resonance

    SciTech Connect

    Shevchenko, A.; Burda, O.; Kalmykov, Y.; Neumann-Cosel, P. von; Ponomarev, V. Yu.; Richter, A.; Wambach, J.; Carter, J.; Sideras-Haddad, E.; Cooper, G. R. J.; Fearick, R. W.; Foertsch, S. V.; Lawrie, J. J.; Neveling, R.; Smit, F. D.; Fujita, H.; Fujita, Y.; Lacroix, D.

    2009-04-15

    Fine structure in the region of the isoscalar giant quadrupole resonance (ISGQR) in {sup 58}Ni, {sup 89}Y, {sup 90}Zr, {sup 120}Sn, {sup 166}Er, and {sup 208}Pb has been observed in high-energy-resolution ({delta}E{sub 1/2}{approx_equal}35-50 keV) inelastic proton scattering measurements at E{sub 0}=200 MeV at iThemba LABS. Calculations of the corresponding quadrupole excitation strength functions performed within models based on the random-phase approximation (RPA) reveal similar fine structure when the mixing of one-particle one-hole states with two-particle two-hole states is taken into account. A detailed comparison of the experimental data is made with results from the quasiparticle-phonon model (QPM) and the extended time-dependent Hartree-Fock (ETDHF) method. For {sup 208}Pb, additional theoretical results from second RPA and the extended theory of finite Fermi systems (ETFFS) are discussed. A continuous wavelet analysis of the experimental and the calculated spectra is used to extract dominant scales characterizing the fine structure. Although the calculations agree with qualitative features of these scales, considerable differences are found between the model and experimental results and amongst different models. Within the framework of the QPM and ETDHF calculations it is possible to decompose the model spaces into subspaces approximately corresponding to different damping mechanisms. It is demonstrated that characteristic scales mainly arise from the collective coupling of the ISGQR to low-energy surface vibrations.

  5. Isoscalar monopole and dipole excitations of cluster states and giant resonances in 12C

    NASA Astrophysics Data System (ADS)

    Kanada-En'yo, Yoshiko

    2016-05-01

    The isoscalar monopole (ISM) and dipole (ISD) excitations in 12C are investigated theoretically with the shifted antisymmetrized molecular dynamics (AMD) plus 3 α -cluster generator coordinate method (GCM). The small-amplitude vibration modes are described by coherent one-particle one-hole excitations expressed by a small shift of single-nucleon Gaussian wave functions within the AMD framework, whereas the large-amplitude cluster modes are incorporated by superposing 3 α -cluster wave functions in the GCM. The coupling of the excitations in the intrinsic frame with the rotation and parity transformation is taken into account microscopically by the angular-momentum and parity projections. The present a calculation that describes the ISM and ISD excitations over a wide energy region covering cluster modes in the low-energy region and the giant resonances in the high-energy region, although the quantitative description of the high-energy part is not satisfactory. The low-energy ISM and ISD strengths of the cluster modes are enhanced by the distance motion between α clusters, and they split into a couple of states because of the angular motion of α clusters. The low-energy ISM strengths exhaust 26% of the energy-weighted sum rule, which is consistent with the experimental data for the 12C(02+; 7.65 MeV) and 12C(03+; 10.3 MeV) measured by (e ,e') ,(α ,α') , and (6Li,6Li' ) scatterings. In the calculated low-energy ISD strengths, two 1- states (the 11- and 12- states) with the significant strengths are obtained over E =10 -15 MeV. The results indicate that the ISD excitations can be a good probe to experimentally search for new cluster states such as the 12C(12-) obtained in the present calculation.

  6. Magnetic resonance imaging in the diagnosis and follow-up of giant cell arteritis: case report and review of literature

    PubMed Central

    Gračanin, Ana Gudelj; Ćurić, Josip; Lončarević, Jelena; Morović-Vergles, Jadranka

    2015-01-01

    A female patient with giant cell vasculitis of the abdominal aorta and its branches and strongly suspected of having extrapulmonary tuberculosis is presented. The diagnoses were based on the clinical picture, laboratory findings, and magnetic resonance imaging (MRI) findings. MRI is highly useful in cases where echosonography and/or vascular biopsy for histopathological analyses are not possible. A combination of giant cell vasculitis and extrapulmonary tuberculosis is extremely rare, and therefore, choosing the right treatment presents a considerable challenge. MRI performed after 6-month antituberculous therapy and 1-year glucocorticoid plus methotrexate therapy showed normal wall of the aorta and its branches, which was consistent with clinical and laboratory remission. Patients with large vessel vasculitis require regular follow-up by MRI.

  7. Magnetic resonance imaging findings of undifferentiated carcinoma with osteoclast-like giant cells of pancreas.

    PubMed

    Yang, Kyung Yoon; Choi, Joon-Il; Choi, Moon Hyung; Park, Michael Yong; Rha, Sung Eun; Byun, Jae Young; Jung, Eun Sun; Lall, Chandana

    2016-01-01

    Undifferentiated carcinoma with osteoclast-like giant cells is a rare pancreatic and periampullary neoplasm with less than 50 cases reported in the literature. Pathologically, this tumor mimics a giant cell tumor in bones. We report a case of undifferentiated carcinoma with osteoclast-like giant cells in a 55-year-old man presenting as a pancreatic mass with associated regional and distant lymphadenopathy. On T1- and T2-weighted images, the mass shows dark signal intensity which was atypical for a pancreatic adenocarcinoma.

  8. Measurement of the Am241(γ,n)Am240 reaction in the giant dipole resonance region

    NASA Astrophysics Data System (ADS)

    Tonchev, A. P.; Hammond, S. L.; Howell, C. R.; Huibregtse, C.; Hutcheson, A.; Kelley, J. H.; Kwan, E.; Raut, R.; Rusev, G.; Tornow, W.; Kawano, T.; Vieira, D. J.; Wilhelmy, J. B.

    2010-11-01

    The photodisintegration cross section of the radioactive nucleus Am241 has been obtained using activation techniques and monoenergetic γ-ray beams from the HIγS facility. The induced activity of Am240 produced via the Am241(γ,n) reaction was measured in the energy interval from 9 to 16 MeV utilizing high-resolution γ-ray spectroscopy. The experimental data for the Am241(γ,n) reaction in the giant dipole resonance energy region are compared with statistical nuclear-model calculations.

  9. Giant Dipole Resonance in the Hot and Thermalized Ce132 Nucleus: Damping of Collective Modes at Finite Temperature

    NASA Astrophysics Data System (ADS)

    Wieland, O.; Bracco, A.; Camera, F.; Benzoni, G.; Blasi, N.; Brambilla, S.; Crespi, F.; Giussani, A.; Leoni, S.; Mason, P.; Million, B.; Moroni, A.; Barlini, S.; Kravchuk, V. L.; Gramegna, F.; Lanchais, A.; Mastinu, P.; Maj, A.; Brekiesz, M.; Kmiecik, M.; Bruno, M.; Geraci, E.; Vannini, G.; Casini, G.; Chiari, M.; Nannini, A.; Ordine, A.; Ormand, E.

    2006-07-01

    The γ decay of the giant dipole resonance (GDR) in the Ce132 compound nucleus with temperature up to ≈4MeV has been measured, using the reaction Ni64+Zn68 at Ebeam=300, 400, and 500 MeV. The γ and charged particles measured in coincidence with recoils are consistent with a fully equilibrated compound nucleus emission. The GDR width, obtained with the statistical model analysis, is found to increase almost linearly with temperature. This increase is rather well reproduced within a model including thermal shape fluctuations and the lifetime of the compound nucleus.

  10. Measurement of the {sup 241}Am({gamma},n){sup 240}Am reaction in the giant dipole resonance region

    SciTech Connect

    Tonchev, A. P.; Howell, C. R.; Hutcheson, A.; Kwan, E.; Raut, R.; Rusev, G.; Tornow, W.; Hammond, S. L.; Huibregtse, C.; Kelley, J. H.; Kawano, T.; Vieira, D. J.; Wilhelmy, J. B.

    2010-11-15

    The photodisintegration cross section of the radioactive nucleus {sup 241}Am has been obtained using activation techniques and monoenergetic {gamma}-ray beams from the HI{gamma}S facility. The induced activity of {sup 240}Am produced via the {sup 241}Am({gamma},n) reaction was measured in the energy interval from 9 to 16 MeV utilizing high-resolution {gamma}-ray spectroscopy. The experimental data for the {sup 241}Am({gamma},n) reaction in the giant dipole resonance energy region are compared with statistical nuclear-model calculations.

  11. Role of deformation on giant resonances within the quasiparticle random-phase approximation and the Gogny force

    SciTech Connect

    Peru, S.; Goutte, H.

    2008-04-15

    Fully consistent axially-symmetric-deformed quasiparticle random phase approximation (QRPA) calculations have been performed, in which the same Gogny D1S effective force has been used for both the Hartree-Fock-Bogolyubov mean field and the QRPA approaches. Giant resonances calculated in deformed {sup 26-28}Si and {sup 22-24}Mg nuclei as well as in the spherical {sup 30}Si and {sup 28}Mg isotopes are presented. Theoretical results for isovector-dipole and isoscalar monopole, quadrupole, and octupole responses are presented and the impact of the intrinsic nuclear deformation is discussed.

  12. Decay of Isoscalar Electric Giant Resonances in MAGNESIUM-24 and CALCIUM-40.

    NASA Astrophysics Data System (ADS)

    Zwarts, Frederik

    1983-01-01

    This dissertation describes an experimental investigation of the decay properties of the ('24)Mg and ('40)Ca nuclei in the excitation energy region from about 10 MeV to 25 MeV (the giant resonance region). The states in this region were populated by means of inelastic scattering of 120 MeV alpha particles. The scattered alpha particles were detected with a magnetic spectrograph at an angle for which the cross section for excitation of 2('+) (quadrupole) and 0('+) (monopole) states has a maximum. Due to the high resolution of the spectrograph the excitation energy of the states in the mother nuclei could be determined accurately. The decay of these states was studied by means of a coincidence experiment where the decay products, protons and alpha particles at low energy (less than 25 MeV), were detected in coincidence with the inelastically scattered alpha particles. Since this measurement is kinematically complete, the excitation energy of the daughter nuclei could be determined, as well. The angular correlation of the decay products, in particular of the alpha decay to the ground state, is typical for the spin and parity of the excited state in the mother nucleus. Most of the strength found in the region 10-16 MeV could in this way by proven to be quadrupole strength, in agreement with other experiments. However, also some monopole strength has been found (8%-20% of the energy weighted sumrule strength (EWSR) in ('24)Mg and 4%-15% EWSR in ('40)Ca). For an excitation energy beyond the Q-value of the decay plus the Coulomb barrier the forward backward asymmetry of the angular correlations increases very rapidly for most of the decay channels. This is explained by taking into account the contribution of the quasi-elastic knock -out reactions. In the case of ('24)Mg it is concluded from the shape of the measured spectra that a (coherent) interference of the two processes is present. The probability of the different decay channels as a function of the excitation energy

  13. USING SCHUMANN RESONANCE MEASUREMENTS FOR CONSTRAINING THE WATER ABUNDANCE ON THE GIANT PLANETS-IMPLICATIONS FOR THE SOLAR SYSTEM'S FORMATION

    SciTech Connect

    Simoes, Fernando; Pfaff, Robert; Klenzing, Jeffrey; Freudenreich, Henry; Bromund, Kenneth; Martin, Steven; Rowland, Douglas; Takahashi, Yukihiro; Yair, Yoav

    2012-05-01

    The formation and evolution of the solar system is closely related to the abundance of volatiles, namely water, ammonia, and methane in the protoplanetary disk. Accurate measurement of volatiles in the solar system is therefore important for understanding not only the nebular hypothesis and origin of life but also planetary cosmogony as a whole. In this work, we propose a new remote sensing technique to infer the outer planets' water content by measuring Tremendously and Extremely Low Frequency (TLF-ELF) electromagnetic wave characteristics (Schumann resonances) excited by lightning in their gaseous envelopes. Schumann resonance detection can be potentially used for constraining the uncertainty of volatiles of the giant planets, mainly Uranus and Neptune, because such TLF-ELF wave signatures are closely related to the electric conductivity profile and water content.

  14. A SECOND GIANT PLANET IN 3:2 MEAN-MOTION RESONANCE IN THE HD 204313 SYSTEM

    SciTech Connect

    Robertson, Paul; Endl, Michael; Cochran, William D.; MacQueen, Phillip J.; Brugamyer, Erik J.; Barnes, Stuart I.; Caldwell, Caroline; Horner, J.; Wittenmyer, Robert A.; Simon, Attila E.

    2012-07-20

    We present eight years of high-precision radial velocity (RV) data for HD 204313 from the 2.7 m Harlan J. Smith Telescope at McDonald Observatory. The star is known to have a giant planet (Msin i = 3.5 M{sub J} ) on a {approx}1900 day orbit, and a Neptune-mass planet at 0.2 AU. Using our own data in combination with the published CORALIE RVs of Segransan et al., we discover an outer Jovian (Msin i = 1.6 M{sub J} ) planet with P {approx} 2800 days. Our orbital fit suggests that the planets are in a 3:2 mean motion resonance, which would potentially affect their stability. We perform a detailed stability analysis and verify that the planets must be in resonance.

  15. Using Schumann Resonance Measurements for Constraining the Water Abundance on the Giant Planets—Implications for the Solar System's Formation

    NASA Astrophysics Data System (ADS)

    Simões, Fernando; Pfaff, Robert; Hamelin, Michel; Klenzing, Jeffrey; Freudenreich, Henry; Béghin, Christian; Berthelier, Jean-Jacques; Bromund, Kenneth; Grard, Rejean; Lebreton, Jean-Pierre; Martin, Steven; Rowland, Douglas; Sentman, Davis; Takahashi, Yukihiro; Yair, Yoav

    2012-05-01

    The formation and evolution of the solar system is closely related to the abundance of volatiles, namely water, ammonia, and methane in the protoplanetary disk. Accurate measurement of volatiles in the solar system is therefore important for understanding not only the nebular hypothesis and origin of life but also planetary cosmogony as a whole. In this work, we propose a new remote sensing technique to infer the outer planets' water content by measuring Tremendously and Extremely Low Frequency (TLF-ELF) electromagnetic wave characteristics (Schumann resonances) excited by lightning in their gaseous envelopes. Schumann resonance detection can be potentially used for constraining the uncertainty of volatiles of the giant planets, mainly Uranus and Neptune, because such TLF-ELF wave signatures are closely related to the electric conductivity profile and water content.

  16. Using Schumann Resonance Measurements for Constraining the Water Abundance on the Giant Planets - Implications for the Solar System Formation

    NASA Technical Reports Server (NTRS)

    Simoes, Fernando; Pfaff, Robert; Hamelin, Michel; Klenzing, Jeffrey; Freudenreich, Henry; Beghin, Christian; Berthelier, Jean-Jacques; Bromund, Kenneth; Grard, Rejean; Lebreton, Jean-Pierre; Martin, Steven; Rowland, Douglas; Sentman, Davis; Takahashi, Yukihiro; Yair, Yoav

    2012-01-01

    The formation and evolution of the Solar System is closely related to the abundance of volatiles, namely water, ammonia, and methane in the protoplanetary disk. Accurate measurement of volatiles in the Solar System is therefore important to understand not only the nebular hypothesis and origin of life but also planetary cosmogony as a whole. In this work, we propose a new, remote sensing technique to infer the outer planets water content by measuring Tremendously and Extremely Low Frequency (TLF-ELF) electromagnetic wave characteristics (Schumann resonances) excited by lightning in their gaseous envelopes. Schumann resonance detection can be potentially used for constraining the uncertainty of volatiles of the giant planets, mainly Uranus and Neptune, because such TLF-ELF wave signatures are closely related to the electric conductivity profile and water content.

  17. Giant dipole resonance built on hot rotating nuclei produced during evaporation of light particles from the 88Mo compound nucleus

    NASA Astrophysics Data System (ADS)

    Ciemała, M.; Kmiecik, M.; Maj, A.; Mazurek, K.; Bracco, A.; Kravchuk, V. L.; Casini, G.; Barlini, S.; Baiocco, G.; Bardelli, L.; Bednarczyk, P.; Benzoni, G.; Bini, M.; Blasi, N.; Brambilla, S.; Bruno, M.; Camera, F.; Carboni, S.; Cinausero, M.; Chbihi, A.; Chiari, M.; Corsi, A.; Crespi, F. C. L.; D'Agostino, M.; Degerlier, M.; Fornal, B.; Giaz, A.; Gramegna, F.; Krzysiek, M.; Leoni, S.; Marchi, T.; Matejska-Minda, M.; Mazumdar, I.; Meczyński, W.; Million, B.; Montanari, D.; Morelli, L.; Myalski, S.; Nannini, A.; Nicolini, R.; Pasquali, G.; Piantelli, S.; Prete, G.; Roberts, O. J.; Schmitt, Ch.; Styczeń, J.; Szpak, B.; Valdré, S.; Wasilewska, B.; Wieland, O.; Wieleczko, J. P.; Ziebliński, M.; Dudek, J.; Dinh Dang, N.

    2015-05-01

    High-energy giant dipole resonance (GDR) γ rays were measured following the decay of the hot, rotating compound nucleus of 88Mo, produced at excitation energies of 124 and 261 MeV. The reaction 48Ti + 40Ca at 300 and 600 MeV bombarding energies has been used. The data were analyzed using the statistical model Monte Carlo code gemini++. It allowed extracting the giant dipole resonance parameters by fitting the high-energy γ -ray spectra. The extracted GDR widths were compared with the available data at lower excitation energy and with theoretical predictions based on (i) The Lublin-Strasbourg drop macroscopic model, supplemented with thermal shape fluctuations analysis, and (ii) The phonon damping model. The theoretical predictions were convoluted with the population matrices of evaporated nuclei from the statistical model gemini++. Also a comparison with the results of a phenomenological expression based on the existing systematics, mainly for lower temperature data, is presented and discussed. A possible onset of a saturation of the GDR width was observed around T =3 MeV.

  18. Probing nuclear shapes close to the fission limit with the giant dipole resonance in {sup 216}Rn

    SciTech Connect

    Kmiecik, M.; Maj, A.; Brekiesz, M.; Krolas, W.; Meczynski, W.; Styczen, J.; Zieblinski, M.; Million, B.; Bracco, A.; Camera, F.; Benzoni, G.; Leoni, S.; Wieland, O.; Brambilla, S.; Herskind, B.; Kicinska-Habior, M.; Dubray, N.; Dudek, J.; Schunck, N.

    2004-12-01

    The gamma-ray decay of the giant dipole resonance (GDR) in the compound nucleus {sup 216}Rn formed with the reaction {sup 18}O+{sup 198}Pt at the bombarding energy of 96 MeV was investigated. High-energy gamma-ray spectra in coincidence with both prompt and delayed low-energy transitions were measured. The obtained GDR width at the average temperature {approx_equal}1 MeV was found to be larger than that at T=0 MeV and to be approximately constant as a function of spin. The measured width value of 7 MeV is found to be consistent with the predictions based on calculations of the nuclear shape distribution using the newest approach for the treatment of the fission barrier within the liquid drop model. The present study is the first investigation of the giant dipole resonance width from the fusion-evaporation decay channel in this nuclear mass range.

  19. (. pi. sup +- ,. pi. sup +- prime N) reactions on sup 12 C and sup 208 Pb near the giant resonance region

    SciTech Connect

    Yoo, Sung Hoon.

    1990-05-01

    Angular distributions for the {sup 12}C({pi}{sup {plus minus}}, {pi}{sup {plus minus}}{prime} p) and {sup 208}Pb({pi}{sup {plus minus}}, {pi}{sup {plus minus}}{prime} p or n) reactions near the giant resonance region have been measured at T{sub {pi}} = 180 MeV, and found different between {pi}{sup +} and {pi}{sup {minus}} data. This observation is interpreted as evidence for different excitation mechanisms dominating the {pi}{sup {minus}}-nucleus and {pi}{sup +}-nucleus interactions in the giant resonance region of these targets. A comparison with the single-nucleon knock-out distorted-wave impulse approximation calculations shows, even though these calculations underestimate ({pi}{sup {plus minus}}, {pi}{sup {plus minus}}{prime} N) data for both targets, the dominance of direct process for ({pi}{sup +}, {pi}{sup {plus}}{prime} p) or ({pi}{sup {minus}}, {pi}{sup {minus}}{prime} n) in contrast to ({pi}{sup {minus}}, {pi}{sup {minus}}{prime} p) or ({pi}{sup +}, {pi}{sup +}{prime} n). In the ({pi}{sup +}, {pi}{sup +}{prime} p) reaction proton-proton hole states are excited directly and appear to have a large probability for direct decay with escape width, whereas in ({pi}{sup {minus}}, {pi}{sup {minus}}{prime} p) the preferentially excited neutron-neutron hole doorway states couple to resonance states and decay with spreading width. This interpretation led us to suggest that the ratio of cross-sections for inelastic scattering to the giant resonance region should be written in terms of an incoherent sum of cross-sections to neutron and proton doorway states. In a heavy nucleus such as {sup 208}Pb, neutron and proton doorway states. In a heavy nucleus such as {sup 208}Pb, neutron and proton doorway states contribute incoherently because the different decay processes do not populate the same final states of the residual nucleus.

  20. Dynamics of an [Fe4S4(SPh)4]2- cluster explored via IR, Raman, and nuclear resonance vibrational spectroscopy (NRVS)-analysis using 36S substitution, DFT calculations, and empirical force fields.

    PubMed

    Xiao, Yuming; Koutmos, Markos; Case, David A; Coucouvanis, Dimitri; Wang, Hongxin; Cramer, Stephen P

    2006-05-14

    We have used four vibrational spectroscopies--FT-IR, FT-Raman, resonance Raman, and 57Fe nuclear resonance vibrational spectroscopy (NRVS)--to study the normal modes of the Fe-S cluster in [(n-Bu)4N]2[Fe4S4(SPh)4]. This [Fe4S4(SR)4]2- complex serves as a model for the clusters in 4Fe ferredoxins and high-potential iron proteins (HiPIPs). The IR spectra exhibited differences above and below the 243 K phase transition. Significant shifts with 36S substitution into the bridging S positions were also observed. The NRVS results were in good agreement with the low temperature data from the conventional spectroscopies. The NRVS spectra were interpreted by normal mode analysis using optimized Urey-Bradley force fields (UBFF) as well as from DFT theory. For the UBFF calculations, the parameters were refined by comparing calculated and observed NRVS frequencies and intensities. The frequency shifts after 36S substitution were used as an additional constraint. A D 2d symmetry Fe4S4S'4 model could explain most of the observed frequencies, but a better match to the observed intensities was obtained when the ligand aromatic rings were included for a D 2d Fe4S4(SPh)4 model. The best results were obtained using the low temperature structure without symmetry constraints. In addition to stretching and bending vibrations, low frequency modes between approximately 50 and 100 cm(-1) were observed. These modes, which have not been seen before, are interpreted as twisting motions with opposing sides of the cube rotating in opposite directions. In contrast with a recent paper on a related Fe4S4 cluster, we find no need to assign a large fraction of the low frequency NRVS intensity to 'rotational lattice modes'. We also reassign the 430 cm(-1) band as primarily an elongation of the thiophenolate ring, with approximately 10% terminal Fe-S stretch character. This study illustrates the benefits of combining NRVS with conventional Raman and IR analysis for characterization of Fe-S centers. DFT

  1. Pump-probe photoelectron velocity-map imaging of autoionizing singly excited 4s{sup 1}4p{sup 6}np{sup 1}(n=7,8) and doubly excited 4s{sup 2}4p{sup 4}5s{sup 1}6p{sup 1} resonances in atomic krypton

    SciTech Connect

    Doughty, Benjamin; Haber, Louis H.; Leone, Stephen R.

    2011-10-15

    Pump-probe photoelectron velocity-map imaging, using 27-eV high-harmonic excitation and 786-nm ionization, is used to resolve overlapping autoionizing resonances in atomic krypton, obtaining two-photon photoelectron angular distributions (PADs) for singly and doubly excited states. Two features in the photoelectron spectrum are assigned to singly excited 4s{sup 1}4p{sup 6}np{sup 1} (n = 7,8) configurations and four features provide information about double excitation configurations. The anisotropy parameters for the singly excited 7p configuration are measured to be {beta}{sub 2} = 1.61 {+-} 0.06 and {beta}{sub 4} = 1.54 {+-} 0.16 while the 8p configuration gives {beta}{sub 2} = 1.23 {+-} 0.19 and {beta}{sub 4} = 0.60 {+-} 0.15. These anisotropies most likely represent the sum of overlapping PADs from states of singlet and triplet spin multiplicities. Of the four bands corresponding to ionization of doubly excited states, two are assigned to 4s{sup 2}4p{sup 4}5s{sup 1}6p{sup 1} configurations that are probed to different J-split ion states. The two remaining doubly excited states are attributed to a previously observed, but unassigned, resonance in the vacuum-ultraviolet photoabsorption spectrum. The PADs from each of the double excitation states are also influenced by overlap from neighboring states that are not completely spectrally resolved. The anisotropies of the observed double excitation states are reported, anticipating future theoretical and experimental work to separate the overlapping PADs into the state resolved PADs. The results can be used to test theories of excited state ionization.

  2. How the presence of a gas giant affects the formation of mean-motion resonances between two low-mass planets in a locally isothermal gaseous disc

    NASA Astrophysics Data System (ADS)

    Podlewska-Gaca, E.; Szuszkiewicz, E.

    2014-03-01

    In this paper we investigate the possibility of a migration-induced resonance locking in systems containing three planets, namely an Earth analogue (1 M⊕), a super-Earth (4 M⊕) and a gas giant (one Jupiter mass). The planets have been listed in order of increasing orbital periods. All three bodies are embedded in a locally isothermal gaseous disc and orbit around a solar mass star. We are interested in answering the following questions: will the low-mass planets form the same resonant structures with each other in the vicinity of the gas giant as in the case when the gas giant is absent? More in general, how will the presence of the gas giant affect the evolution of the two low-mass planets? When there is no gas giant in the system, it has been already shown that if the two low-mass planets undergo a convergent differential migration, they will capture each other in a mean-motion resonance. For the choices of disc parameters and planet masses made in this paper, the formation of the 5:4 resonance in the absence of the Jupiter has been observed in a previous investigation and confirmed here. In this work we add a gas giant on the most external orbit of the system in such a way that its differential migration is convergent with the low-mass planets. We show that the result of this set-up is the speeding up of the migration of the super-Earth and, after that, all three planets become locked in a triple mean-motion resonance. However, this resonance is not maintained due to the low-mass planet eccentricity excitation, a fact that leads to close encounters between planets and eventually to the ejection from the internal orbits of one or both low-mass planets. We have observed that the ejected low-mass planets can leave the system, fall into a star or become the external planet relative to the gas giant. In our simulations the latter situation has been observed for the super-Earth. It follows from the results presented here that the presence of a Jupiter-like planet

  3. Relating the 4s{sigma}{sup -1} inner-valence photoelectron spectrum of HBr with the Br 3d{sup -1}5l{lambda} resonant Auger spectra: An approach to the assignments

    SciTech Connect

    Puettner, R.; Hu, Y. F.; Bancroft, G. M.; Kivimaeki, A.; Jurvansuu, M.; Aksela, H.; Aksela, S.

    2003-09-01

    The high resolution Br 4s{sigma}{sup -1} photoelectron spectrum of HBr is presented together with the resonant Auger spectra resulting from excitations from the 3d core levels to the low-n Rydberg orbitals 5s{sigma}, 5p{sigma}, and 5p{pi}. The very complex spectra can be broadly assigned using two observations. First, the energy splittings of the 4p{pi}{sup -2}5s and 4p{pi}{sup -2}5p states are very similar to the splittings of the 4p{pi}{sup -2}({sup 1}{sigma}{sup +},{sup 1}{delta}, and {sup 3}{sigma}{sup -}) final states seen previously in the normal Auger spectra. Second, the {sup 2}{sigma}{sup +} states, which are the dominant correlation satellites in the complex 4s{sigma}{sup -1} photoelectron spectrum, are often enhanced in the 5s{sigma} resonance Auger spectra. Electron correlation and spin-orbit interaction in the final states are important to understand all of these spectra. Unlike the normal Auger spectra, vibrational excitations play only a minor role in these spectra, showing that the 5s and 5p Rydberg orbitals have some bonding character.

  4. Precise radial velocities of giant stars. VI. A possible 2:1 resonant planet pair around the K giant star η Ceti

    NASA Astrophysics Data System (ADS)

    Trifonov, Trifon; Reffert, Sabine; Tan, Xianyu; Lee, Man Hoi; Quirrenbach, Andreas

    2014-08-01

    We report the discovery of a new planetary system around the K giant η Cet (HIP 5364, HD 6805, HR 334) based on 118 high-precision optical radial velocities taken at Lick Observatory since July 2000. Since October 2011 an additional nine near-infrared Doppler measurements have been taken using the ESO CRIRES spectrograph (VLT, UT1). The visible data set shows two clear periodicities. Although we cannot completely rule out that the shorter period is due to rotational modulation of stellar features, the infrared data show the same variations as in the optical, which strongly supports that the variations are caused by two planets. Assuming the mass of η Cet to be 1.7 M⊙, the best edge-on coplanar dynamical fit to the data is consistent with two massive planets (mb sini = 2.6 ± 0.2 MJup, mc sini = 3.3 ± 0.2 MJup), with periods of Pb = 407 ± 3 days and Pc = 740 ± 5 days and eccentricities of eb = 0.12 ± 0.05 and ec = 0.08 ± 0.04. These mass and period ratios suggest possible strong interactions between the planets, and a dynamical test is mandatory. We tested a wide variety of edge-on coplanar and inclined planetary configurations for stability, which agree with the derived radial velocities. We find that for a coplanar configuration there are several isolated stable solutions and two well defined stability regions. In certain orbital configurations with moderate eb eccentricity, the planets can be effectively trapped in an anti-aligned 2:1 mean motion resonance that stabilizes the system. A much larger non-resonant stable region exists in low-eccentricity parameter space, although it appears to be much farther from the best fit than the 2:1 resonant region. In all other cases, the system is categorized as unstable or chaotic. Another conclusion from the coplanar inclined dynamical test is that the planets can be at most a factor of ~1.4 more massive than their suggested minimum masses. Assuming yet higher inclinations, and thus larger planetary masses, leads

  5. Giant photoluminescence enhancement in SiC nanocrystals by resonant semiconductor exciton-metal surface plasmon coupling

    NASA Astrophysics Data System (ADS)

    Dai, Dejian; Dong, Zhenggao; Fan, Jiyang

    2013-01-01

    We report giant fluorescence enhancement in SiC nanocrystals (NCs) embedded in a sodium dodecyl sulfonate dielectric medium by proximately contacted Ag nanoparticles. The enhancement in integrated fluorescence intensity reaches an astonishing 176-fold under 360 nm excitation (53.3-fold enhancement in emission maximum intensity). Finite-element simulation indicates that the strong resonant coupling between the excited SiC NCs and localized surface plasmons of the Ag nanoparticles plays a dominant role in determining fluorescence enhancement. In contrast, the absorption enhancement caused by light concentration around the Ag nanoparticles makes only a slight contribution to the overall enhancement. Our result opens the possibility of applications of these highly enhanced fluorescent SiC NCs in diverse areas such as sensing, optoelectronics and life sciences.

  6. Giant photoluminescence enhancement in SiC nanocrystals by resonant semiconductor exciton-metal surface plasmon coupling.

    PubMed

    Dai, Dejian; Dong, Zhenggao; Fan, Jiyang

    2013-01-18

    We report giant fluorescence enhancement in SiC nanocrystals (NCs) embedded in a sodium dodecyl sulfonate dielectric medium by proximately contacted Ag nanoparticles. The enhancement in integrated fluorescence intensity reaches an astonishing 176-fold under 360 nm excitation (53.3-fold enhancement in emission maximum intensity). Finite-element simulation indicates that the strong resonant coupling between the excited SiC NCs and localized surface plasmons of the Ag nanoparticles plays a dominant role in determining fluorescence enhancement. In contrast, the absorption enhancement caused by light concentration around the Ag nanoparticles makes only a slight contribution to the overall enhancement. Our result opens the possibility of applications of these highly enhanced fluorescent SiC NCs in diverse areas such as sensing, optoelectronics and life sciences. PMID:23238520

  7. Application of an extended random-phase approximation to giant resonances in light-, medium-, and heavy-mass nuclei

    NASA Astrophysics Data System (ADS)

    Tselyaev, V.; Lyutorovich, N.; Speth, J.; Krewald, S.; Reinhard, P.-G.

    2016-09-01

    We present results of the time blocking approximation (TBA) for giant resonances in light-, medium-, and heavy-mass nuclei. The TBA is an extension of the widely used random-phase approximation (RPA) adding complex configurations by coupling to phonon excitations. A new method for handling the single-particle continuum is developed and applied in the present calculations. We investigate in detail the dependence of the numerical results on the size of the single-particle space and the number of phonons as well as on nuclear matter properties. Our approach is self-consistent, based on an energy-density functional of Skyrme type where we used seven different parameter sets. The numerical results are compared with experimental data.

  8. Giant dipole resonance in 88Mo from phonon damping model strength functions averaged over temperature and angular momentum distributions

    NASA Astrophysics Data System (ADS)

    Dinh Dang, N.; Ciemala, M.; Kmiecik, M.; Maj, A.

    2013-05-01

    The line shapes of giant dipole resonance (GDR) in the decay of the compound nucleus 88Mo, which is formed after the fusion-evaporation reaction 48Ti + 40Ca at various excitation energies E* from 58 to 308 MeV, are generated by averaging the GDR strength functions predicted within the phonon damping model (PDM) using the empirical probabilities for temperature and angular momentum. The average strength functions are compared with the PDM strength functions calculated at the mean temperature and mean angular momentum, which are obtained by averaging the values of temperature and angular momentum using the same temperature and angular momentum probability distributions, respectively. It is seen that these two ways of generating the GDR linear line shape yield very similar results. It is also shown that the GDR width approaches a saturation at angular momentum J≥ 50 ℏ at T=4 MeV and at J≥ 70 ℏ at any T.

  9. [A model of using magnetic resonance imaging in osteoarticular tumor lesion in case of giant cell tumors].

    PubMed

    Sherman, L A

    2004-01-01

    Fifty-eight patients with giant cell tumors (GCT) underwent a comprehensive radiation diagnosis involving X-ray study and magnetic resonance imaging (MRI). The obtained MR images indicated the high efficiency of this combination of radiation diagnostic techniques in solving the problems in the visualization of osteoarticular tumor lesions. GCT is characterized by well-known primary X-ray semiotics; MR images are also rather pathognomonic of these tumors and they illustrate the process of morphogenesis of these masses. MRI made it possible to solve the specific problems facing a physician (a radiation diagnostician), to determine the site, shape, sizes, volume, and local extent of a tumor, which permitted the planning of surgical treatment policy; to assess its results, to reveal possible inflammatory complications; and to visualize a local recurrence and on-going growth of a tumor, including the signs of GCT malignancy.

  10. Studies of Pressure-Broadening of Alkali Atom Resonance Lines for Modeling Atmospheres of Extrasolar Giant Planets and Brown Dwarfs

    NASA Technical Reports Server (NTRS)

    Kirby, Kate; Babb, J.; Yoshino, K.

    2004-01-01

    In L-dwarfs and T-dwarfs the resonance lines of sodium and potassium are so profoundly pressure-broadened that their wings extend several hundred nanometers from line center. With accurate knowledge of the line profiles as a function of temperature and pressure: such lines can prove to be valuable diagnostics of the atmospheres of such objects. We have initiated a joint program of theoretical and experimental research to study the line-broadening of alkali atom resonance lines due to collisions with species such as helium and molecular hydrogen. Although potassium and sodium are the alkali species of most interest in the atmospheres of cool brown dwarfs and extrasolar giant planets, some of our theoretical focus this year has involved the calculation of pressure-broadening of lithium resonance lines by He, as a test of a newly developed suite of computer codes. In addition, theoretical calculations have been carried out to determine the leading long range van der Waals coefficients for the interactions of ground and excited alkali metal atoms with helium atoms, to within a probable error of 2%. Such data is important in determining the behavior of the resonance line profiles in the far wings. Important progress has been made on the experimental aspects of the program since the arrival of a postdoctoral fellow in September. A new absorption cell has been designed, which incorporates a number of technical improvements over the previous cell, including a larger cell diameter to enhance the signal, and fittings which allow for easier cleaning, thereby significantly reducing the instrument down-time.

  11. Atom Resonance Lines for Modeling Atmosphere: Studies of Pressure-Broadening of Alkali Atom Resonance Lines for Modeling Atmospheres of Extrasolar Giant Planets and Brown Dwarfs

    NASA Technical Reports Server (NTRS)

    Hasan, Hashima (Technical Monitor); Kirby, K.; Babb, J.; Yoshino, K.

    2005-01-01

    We report on progress made in a joint program of theoretical and experimental research to study the line-broadening of alkali atom resonance lines due to collisions with species such as helium and molecular hydrogen. Accurate knowledge of the line profiles of Na and K as a function of temperature and pressure will allow such lines to serve as valuable diagnostics of the atmospheres of brown dwarfs and extra-solar giant planets. A new experimental apparatus has been designed, built and tested over the past year, and we are poised to begin collecting data on the first system of interest, the potassium resonance lines perturbed by collisions with helium. On the theoretical front, calculations of line-broadening due to sodium collisions with helium are nearly complete, using accurate molecular potential energy curves and transition moments just recently computed for this system. In addition we have completed calculations of the three relevant potential energy curves and associated transition moments for K - He, using the MOLPRO quantum chemistry codes. Currently, calculations of the potential surfaces describing K-H2 are in progress.

  12. Configuration-interaction-induced dynamic spin polarization of the Ar*(2p{sub 1/2,3/2}{sup -1}4s{sub 1/2}){sub J=1} resonant Auger decay

    SciTech Connect

    Lohmann, B.; Langer, B.; Snell, G.; Canton, S.; Berrah, N.; Kleiman, U.; Becker, U.; Martins, M.

    2005-02-01

    Spin-resolved measurements of the Ar{sup *}(2p{sub 1/2,3/2}{sup -1}4s{sub 1/2}){sub J=1} resonantly excited L{sub 2,3}M{sub 2,3}M{sub 2,3} Auger decay have been performed. The low resolution Auger spectrum, which due to cancellation between different multiplet components should exhibit virtually zero dynamic spin polarization, reveals an unexpected nonvanishing polarization effect. Calculations within a relativistic distorted wave approximation explain this effect as configuration-interaction (CI) induced. The CI generates experimentally unresolved fine structure components with low and high total angular momentum, giving rise to asymmetric cases where the high J part of certain multiplets is suppressed by internal selection rules for diagram lines. In this case, only the low J components survive with no partner for spin-polarization cancellation.

  13. Giant in-particle field concentration and Fano resonances at light scattering by high-refractive-index particles

    NASA Astrophysics Data System (ADS)

    Tribelsky, Michael I.; Miroshnichenko, Andrey E.

    2016-05-01

    We present the results of a detailed analytical study of light scattering by a particle with high refractive index m +i κ and low losses (m ≫1 ,0 <κ ≪1 ) based on the exact Mie solution. We show that there is a dramatic difference in the behavior of the electromagnetic field within the particle (inner problem) and outside it (outer problem). With an increase in m at fixed values of the other parameters, the field within the particle asymptotically converges to a periodic function of m . The electric and magnetic type Mie resonances of different orders overlap substantially. It may lead to a giant concentration of the electromagnetic energy within the particle. At the same time, we demonstrate that the solution for the outer problem makes it possible to present each partial scattered wave as a sum of two partitions. One of them corresponds to the m -independent wave, scattered by a perfectly reflecting particle and plays the role of a background, while the other is associated with the excitation of a sharply m -dependent resonant Mie mode. The interference of the partitions brings about a typical asymmetric Fano profile. The profile is obtained from the exact Mie solution by means of identical transformations without any additional assumptions and/or fitting. It makes it possible to generalize rigorously the Fano theory to the case of finite dissipation. At an increase in m the Fano resonances in the outer problem die out and the scattered field converges to the universal, m -independent profile. The behavior of the resonances at a fixed m and varying particle size parameter (x ) is also discussed in detail. The similarities and differences of the two cases (fixed x , varying m and fixed m , varying x ) are disclosed. We also show that under certain very general conditions the scattering cross section of a large lossy sphere cannot be smaller than half its geometric cross section, while its absorption cross section cannot exceed three halves of the geometric

  14. Giant Dipole Resonance in the hot and thermalized 132Ce nucleus: damping of collective modes at finite temperature

    SciTech Connect

    Wieland, O; Bracco, A; Camera, F; Benzoni, G; Blasi, N; Brambilla, S; Crespi, F; Giussani, A; Leoni, S; Million, B; Moroni, A; Barlini, S; Kravchuk, V L; Gramegna, F; Lanchais, A; Mastinu, P; Maj, A; Brekiesz, M; Kmiecik, M; Bruno, M; Geraci, E; Vannini, G; Casini, G; Chiari, M; Nannini, A; Ordine, A; Ormand, W E

    2006-06-16

    The {gamma} decay of the Giant Dipole Resonance in the {sup 132}Ce compound nucleus with temperature up to {approx} 4 MeV has been measured. The symmetric {sup 64}Ni + {sup 68}Zn at E{sub beam} = 300, 400, 500 MeV and the asymmetric reaction {sup 16}O + {sup 116}Sn at E{sub beam} = 130, 250 MeV have been investigated. Light charged particles and {gamma} rays have been detected in coincidence with the recoiling compound system. In the case of the mass symmetric {sup 64}Ni induced reaction the {gamma} and charged particle spectral shapes are found to be consistent with the emission from a fully equilibrated compound nuclei and the GDR parameters are extracted from the data using a statistical model analysis. The GDR width is found to increase almost linear with temperature. This increase is rather well reproduced within a model which includes both the thermal fluctuation of the nuclear shape and the lifetime of the compound nucleus.

  15. Giant peak to valley ratio in a GaN based resonant tunnel diode with barrier width modulation

    NASA Astrophysics Data System (ADS)

    Sankaranarayanan, Sandeep; Saha, Dipankar

    2016-10-01

    A barrier width modulated GaN based resonant tunnel diode is theoretically proposed which exhibits a giant peak to valley current ratio as high as 60 and a high negative differential conductance (NDC) of 1.77 × 106 S/cm2 with very low valley current density of 3 mA/cm2. This is achieved by the unique characteristic of the device current which monotonically decreases for applied voltages greater than the valley voltage in our simulation window. This is in contrast to all the other negative differential conductance based devices which experience an immediate exponential increase in current after the NDC region. The proposed device is also the first bidirectional tunneling diode which shows negative differential conductance for both polarity of the applied bias which is normally not observed with the conventional GaN/AlGaN double barrier structures due to the strong asymmetry arising from the internal electric fields due to polarization. The unique characteristics of the device can be attributed to the use of a modulated barrier width which is made possible by a polarization modulating InGaN layer and efficient utilization of internal electric fields in III-nitrides.

  16. Spin-isovector giant resonances induced by (n,p) reactions on heavy nuclei

    NASA Astrophysics Data System (ADS)

    Long, S. A.; Spicer, B. M.; Raywood, K. J.; Abegg, R.; Alford, W. P.; Celler, A.; Frekers, D.; Green, P. E.; Häusser, O.; Helmer, R. L.; Henderson, R. S.; Hicks, K. H.; Jackson, K. P.; Jeppesen, R. G.; King, N. S.; Miller, C. A.; Moinester, M. A.; Officer, V. C.; Shute, G. G.; Trudel, A.; Vetterli, M. C.; Yavin, A. I.; Yen, S.

    1998-06-01

    Double differential cross sections from the 120Sn(n,p)120In and 181Ta(n,p)181Hf reactions at 298 MeV and the 238U(n,p)238Pa reaction at 318 MeV have been measured for excitation energies up to 50 MeV in the residual nucleus. These data, together with the previously published data from the 90Zr(n,p)90Y and 208Pb(n,p)208Tl reactions at 198 MeV, have been analyzed for spin-isovector resonances of multipolarities less than 7, using the multipole decomposition method. The strengths due to spin-isovector excitations of multipolarity less than 4 have been extracted. The anomalous behavior of the extracted spin-isovector quadrupole strength with target mass number is discussed with reference to the calculations of Leonardi et al. The cross section due to quasifree processes was calculated and subtracted from the data. The data after this subtraction were reanalyzed for spin-isovector resonances and the strengths due to multipolarities up to 3 were extracted. The strengths due to spin-isovector dipole and octupole excitations were compared to values calculated, for 1ħω transitions only, using the sum rules of Macfarlane. The behavior with target mass number is well represented by these sum rules.

  17. Giant field enhancement and resonant wavelength shift through a composite nanostructure

    NASA Astrophysics Data System (ADS)

    Chen, Qingquan; Zuo, Yiping; Cai, Wei; Zhang, Bin; Pan, Leiting; Yao, Jianghong; Wu, Qiang; Xu, Jingjun

    2014-06-01

    This paper reports a kind of nanostructure composed of a metallic nanosphere pair and a rectangle nanoaperture, which can dramatically enhance the localized optical near-field up to 2100 times larger than the incident optical field. The FEM calculation method was used to investigate the enhancement factors and the coupling effects of different nanostructures. When the composite nanostructures are periodically arranged, the resonance peak can be varied from 560 nm to 760 nm and the electric field enhancement is about 37 percent larger than that of single composite nanostructure. We attribute these phenomena to two-step confinement of the optical electric field and the coupling effect of the composite nanostructures. Both enhancement factors of single and periodic composite nanostructures are sufficient for single molecule detection.

  18. Generating giant and tunable nonlinearity in a macroscopic mechanical resonator from a single chemical bond.

    PubMed

    Huang, Pu; Zhou, Jingwei; Zhang, Liang; Hou, Dong; Lin, Shaochun; Deng, Wen; Meng, Chao; Duan, Changkui; Ju, Chenyong; Zheng, Xiao; Xue, Fei; Du, Jiangfeng

    2016-01-01

    Nonlinearity in macroscopic mechanical systems may lead to abundant phenomena for fundamental studies and potential applications. However, it is difficult to generate nonlinearity due to the fact that macroscopic mechanical systems follow Hooke's law and respond linearly to external force, unless strong drive is used. Here we propose and experimentally realize high cubic nonlinear response in a macroscopic mechanical system by exploring the anharmonicity in chemical bonding interactions. We demonstrate the high tunability of nonlinear response by precisely controlling the chemical bonding interaction, and realize, at the single-bond limit, a cubic elastic constant of 1 × 10(20) N m(-3). This enables us to observe the resonator's vibrational bi-states transitions driven by the weak Brownian thermal noise at 6 K. This method can be flexibly applied to a variety of mechanical systems to improve nonlinear responses, and can be used, with further improvements, to explore macroscopic quantum mechanics.

  19. Giant Electric Field Enhancement in Split Ring Resonators Featuring Nanometer-Sized Gaps

    PubMed Central

    Bagiante, S.; Enderli, F.; Fabiańska, J.; Sigg, H.; Feurer, T.

    2015-01-01

    Today's pulsed THz sources enable us to excite, probe, and coherently control the vibrational or rotational dynamics of organic and inorganic materials on ultrafast time scales. Driven by standard laser sources THz electric field strengths of up to several MVm−1 have been reported and in order to reach even higher electric field strengths the use of dedicated electric field enhancement structures has been proposed. Here, we demonstrate resonant electric field enhancement structures, which concentrate the incident electric field in sub-diffraction size volumes and show an electric field enhancement as high as ~14,000 at 50 GHz. These values have been confirmed through a combination of near-field imaging experiments and electromagnetic simulations. PMID:25623373

  20. Generating giant and tunable nonlinearity in a macroscopic mechanical resonator from a single chemical bond

    PubMed Central

    Huang, Pu; Zhou, Jingwei; Zhang, Liang; Hou, Dong; Lin, Shaochun; Deng, Wen; Meng, Chao; Duan, Changkui; Ju, Chenyong; Zheng, Xiao; Xue, Fei; Du, Jiangfeng

    2016-01-01

    Nonlinearity in macroscopic mechanical systems may lead to abundant phenomena for fundamental studies and potential applications. However, it is difficult to generate nonlinearity due to the fact that macroscopic mechanical systems follow Hooke's law and respond linearly to external force, unless strong drive is used. Here we propose and experimentally realize high cubic nonlinear response in a macroscopic mechanical system by exploring the anharmonicity in chemical bonding interactions. We demonstrate the high tunability of nonlinear response by precisely controlling the chemical bonding interaction, and realize, at the single-bond limit, a cubic elastic constant of 1 × 1020 N m−3. This enables us to observe the resonator's vibrational bi-states transitions driven by the weak Brownian thermal noise at 6 K. This method can be flexibly applied to a variety of mechanical systems to improve nonlinear responses, and can be used, with further improvements, to explore macroscopic quantum mechanics. PMID:27225287

  1. A case of a giant pseudoangiomatous stromal hyperplasia of the breast: magnetic resonance imaging findings.

    PubMed

    Solomou, Ekaterini; Kraniotis, Pantelis; Patriarcheas, Georgios

    2012-04-12

    Pseudoangiomatous stromal hyperplasia (PASH) of the breast is a benign myofibroblastic process. We present the case of a 17-year-old girl who underwent diagnostic work-up due to an enlargement of her left breast. She was submitted to ultrasounds and magnetic resonance imaging (MRI) which depicted a 14 cm lesion in her left breast. The patient was later operated and histology revealed PASH. Although PASH may range from 0.6-12 cm, a few lesions over 12 cm have been described, the largest being 20 cm. Large series present mammographic and ultrasonographic features of PASH in the literature, but little has been reported on the MR characteristics of PASH up to today. Signal on the T1-weighted image (T1WI) and T2-weighted image (T2WI) may vary. Curves generated from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) studies are mainly type I or less frequently type II. There are no reports about diffusion-weighted imaging and corresponding apparent diffusion coefficient (ADC) values for PASH in the literature. ADC values in our case lie within the range of values reported for other benign breast lesions. The presence of slit-like spaces within the lesion on MR imaging along with DCE-MRI type I curve and ADC values consistent with a benign lesion may favour the diagnosis of PASH. Tissue biopsy is necessary, however for the final diagnosis. This case report will further contribute to the understanding of MR imaging features of PASH, especially in cases where mammography is not indicated.

  2. Photoionization of Xe inside C{sub 60}: Atom-fullerene hybridization, giant cross-section enhancement, and correlation confinement resonances

    SciTech Connect

    Madjet, Mohamed E.; Renger, Thomas; Hopper, Dale E.; McCune, Matthew A.; Chakraborty, Himadri S.; Rost, Jan-M.; Manson, Steven T.

    2010-01-15

    A theoretical study of the subshell photoionization of the Xe atom endohedrally confined in C{sub 60} is presented. Powerful hybridization of the Xe 5s state with the bottom edge of C{sub 60} pi band is found that induces strong structures in the 5s ionization, causing the cross section to differ significantly from earlier results that omit this hybridization. The hybridization also affects the angular distribution asymmetry parameter of Xe 5p ionization near the Cooper minimum. The 5p cross section, on the other hand, is greatly enhanced by borrowing considerable oscillator strength from the C{sub 60} giant plasmon resonance via the atom-fullerene dynamical interchannel coupling. Beyond the C{sub 60} plasmon energy range the atomic subshell cross sections display confinement-induced oscillations in which, over the large 4d shape resonance region, the dominant 4d oscillations induce their 'clones' in all degenerate weaker channels known as correlation confinement resonances.

  3. The Pan-Pacific Planet Search. IV. Two Super-Jupiters in a 3:5 Resonance Orbiting the Giant Star HD 33844

    NASA Astrophysics Data System (ADS)

    Wittenmyer, Robert A.; Johnson, John Asher; Butler, R. P.; Horner, Jonathan; Wang, Liang; Robertson, Paul; Jones, M. I.; Jenkins, J. S.; Brahm, R.; Tinney, C. G.; Mengel, M. W.; Clark, J.

    2016-02-01

    We report the discovery of two giant planets orbiting the K giant HD 33844 based on radial velocity data from three independent campaigns. The planets move on nearly circular orbits with semimajor axes {a}b\\=1.60+/- 0.02 AU and {a}c=2.24+/- 0.05 AU, and have minimum masses (m sin i) of {M}b=1.96+/- 0.12 {M}{{Jup}} and {M}c=1.76+/- 0.18 {M}{{Jup}}. Detailed N-body dynamical simulations show that the two planets have remained on stable orbits for more than 106 years for low eccentricities and are most likely trapped in a mutual 3:5 mean motion resonance.

  4. Giant electric field control of magnetism and narrow ferromagnetic resonance linewidth in FeCoSiB/Si/SiO2/PMN-PT multiferroic heterostructures

    NASA Astrophysics Data System (ADS)

    Gao, Y.; Wang, X.; Xie, L.; Hu, Z.; Lin, H.; Zhou, Z.; Nan, T.; Yang, X.; Howe, B. M.; Jones, J. G.; Brown, G. J.; Sun, N. X.

    2016-06-01

    It has been challenging to achieve combined strong magnetoelectric coupling and narrow ferromagnetic resonance (FMR) linewidth in multiferroic heterostructures. Electric field induced large effective field of 175 Oe and narrow FMR linewidth of 40 Oe were observed in FeCoSiB/Si/SiO2/PMN-PT heterostructures with substrate clamping effect minimized through removing the Si substrate. As a comparison, FeCoSiB/PMN-PT heterostructures with FeCoSiB film directly deposited on PMN-PT showed a comparable voltage induced effective magnetic field but a significantly larger FMR linewidth of 283 Oe. These multiferroic heterostructures exhibiting combined giant magnetoelectric coupling and narrow ferromagnetic resonance linewidth offer great opportunities for integrated voltage tunable RF magnetic devices.

  5. Light Charged Particles Emission and the Giant Dipole Resonance in Highly Excited Ce Nucleus Formed in Reactions with Different Mass Asymmetries

    NASA Astrophysics Data System (ADS)

    Barlini, S.; Kravchuk, V. L.; Wieland, O.; Bracco, A.; Gramegna, F.; Airoldi, A.; Benzoni, G.; Blasi, N.; Brambilla, S.; Brekiesz, M.; Bruno, M.; Camera, F.; Casini, G.; Chiari, M.; D'Agostino, M.; De Sanctis, J.; Geraci, E.; Kmiecik, M.; Lanchais, A.; Leoni, S.; Maj, A.; Mastinu, P. F.; Million, B.; Moroni, A.; Nannini, A.; Ordine, A.; Sacchi, R.; Vannini, G.

    2006-08-01

    Recent measurements have been performed at the National Laboratoty of Legnaro using mass-symmetric (400, 500 MeV 64Ni + 68Zn) and mass-asymmetric (250 MeV 16O + 116Sn) entrance channel reactions to form 132Ce compound nucleus at different excitation energies (E*=150, 200 and 200 MeV, respectively). The decay of the composite system has been followed studying the γ-rays and Light Charged Particles (LCP) spectra emitted in coincidence with the Evaporation Residues (ER). In this way the emission mechanism of the LCP, depending on the mass-asymmetry at the entrance channel and on the projectile energy, and the results of the Full Width Half-Maximum (FWHM) of the Giant Dipole Resonance as a function of the nuclear temperature have been studied.

  6. Fourier photospectroscopy of Xe@C60 in the Xe 4d giant resonance region: Testing the single-photoionization theory against recent measurements

    NASA Astrophysics Data System (ADS)

    Patel, Aakash; Chakraborty, Himadri

    2012-06-01

    We have developed a technique, based on Fourier-transforming cross sections to the reciprocal configuration space, to explore the electronic multiple interferences in the photoionization of endohedral fullerene molecules. Using this technique, the single photoionization cross section of endohedral Xe@C60 over Xe 4d giant resonance energy region, calculated in the time dependent local density approximation (TDLDA), is compared with recent double photoionization experimental data [1]. The analysis of oscillatory cross sections derives a number of inherent similarities between the prediction and the data, including a large beating-type oscillation and several others of intermediate size [2]. Results stress the need for more accurate measurements to access the wealth of information about the geometry of the system.[4pt] [1] A.L.D. Kilcoyne et al., Phys. Rev. Lett. 105, 213001 (2010);[0pt] [2] A.B. Patel and H.S. Chakraborty, J. Phys. B Fast Track Comm. 44, 191001 (2011).

  7. X-ray excited photoluminescence near the giant resonance in solid-solution Gd(1-x)Tb(x)OCl nanocrystals and their retention upon solvothermal topotactic transformation to Gd(1-x)Tb(x)F3.

    PubMed

    Waetzig, Gregory R; Horrocks, Gregory A; Jude, Joshua W; Zuin, Lucia; Banerjee, Sarbajit

    2016-01-14

    Design rules for X-ray phosphors are much less established as compared to their optically stimulated counterparts owing to the absence of a detailed understanding of sensitization mechanisms, activation pathways and recombination channels upon high-energy excitation. Here, we demonstrate a pronounced modulation of the X-ray excited photoluminescence of Tb(3+) centers upon excitation in proximity to the giant resonance of the host Gd(3+) ions in solid-solution Gd1-xTbxOCl nanocrystals prepared by a non-hydrolytic cross-coupling method. The strong suppression of X-ray excited optical luminescence at the giant resonance suggests a change in mechanism from multiple exciton generation to single thermal exciton formation and Auger decay processes. The solid-solution Gd1-xTbxOCl nanocrystals are further topotactically transformed with retention of a nine-coordinated cation environment to solid-solution Gd1-xTbxF3 nanocrystals upon solvothermal treatment with XeF2. The metastable hexagonal phase of GdF3 can be stabilized at room temperature through this topotactic approach and is transformed subsequently to the orthorhombic phase. The fluoride nanocrystals indicate an analogous but blue-shifted modulation of the X-ray excited optical luminescence of the Tb(3+) centers upon X-ray excitation near the giant resonance of the host Gd(3+) ions.

  8. Localized surface plasmon resonances dominated giant lateral photovoltaic effect observed in ZnO/Ag/Si nanostructure

    PubMed Central

    Zhang, Ke; Wang, Hui; Gan, Zhikai; Zhou, Peiqi; Mei, Chunlian; Huang, Xu; Xia, Yuxing

    2016-01-01

    We report substantially enlarged lateral photovoltaic effect (LPE) in the ZnO/Ag/Si nanostructures. The maximum LPE sensitivity (55.05 mv/mm) obtained in this structure is about seven times larger than that observed in the control sample (7.88 mv/mm) of ZnO/Si. We attribute this phenomenon to the strong localized surface plasmon resonances (LSPRs) induced by nano Ag semicontinuous films. Quite different from the traditional LPE in PN junction type structures, in which light-generated carriers contributed to LPE merely depends on direct excitation of light in semiconductor, this work firstly demonstrates that, by introducing a super thin metal Ag in the interface between two different kinds of semiconductors, the nanoscale Ag embedded in the interface will produce strong resonance of localized field, causing extra intraband excitation, interband excitation and an enhanced direct excitation. As a consequence, these LSPRs dominated contributions harvest much more carriers, giving rise to a greatly enhanced LPE. In particular, this LSPRs-driven mechanism constitutes a sharp contrast to the traditional LPE operation mechanism. This work suggests a brand new LSPRs approach for tailoring LPE-based devices and also opens avenues of research within current photoelectric sensors area. PMID:26965713

  9. Localized surface plasmon resonances dominated giant lateral photovoltaic effect observed in ZnO/Ag/Si nanostructure

    NASA Astrophysics Data System (ADS)

    Zhang, Ke; Wang, Hui; Gan, Zhikai; Zhou, Peiqi; Mei, Chunlian; Huang, Xu; Xia, Yuxing

    2016-03-01

    We report substantially enlarged lateral photovoltaic effect (LPE) in the ZnO/Ag/Si nanostructures. The maximum LPE sensitivity (55.05 mv/mm) obtained in this structure is about seven times larger than that observed in the control sample (7.88 mv/mm) of ZnO/Si. We attribute this phenomenon to the strong localized surface plasmon resonances (LSPRs) induced by nano Ag semicontinuous films. Quite different from the traditional LPE in PN junction type structures, in which light-generated carriers contributed to LPE merely depends on direct excitation of light in semiconductor, this work firstly demonstrates that, by introducing a super thin metal Ag in the interface between two different kinds of semiconductors, the nanoscale Ag embedded in the interface will produce strong resonance of localized field, causing extra intraband excitation, interband excitation and an enhanced direct excitation. As a consequence, these LSPRs dominated contributions harvest much more carriers, giving rise to a greatly enhanced LPE. In particular, this LSPRs-driven mechanism constitutes a sharp contrast to the traditional LPE operation mechanism. This work suggests a brand new LSPRs approach for tailoring LPE-based devices and also opens avenues of research within current photoelectric sensors area.

  10. Localized surface plasmon resonances dominated giant lateral photovoltaic effect observed in ZnO/Ag/Si nanostructure.

    PubMed

    Zhang, Ke; Wang, Hui; Gan, Zhikai; Zhou, Peiqi; Mei, Chunlian; Huang, Xu; Xia, Yuxing

    2016-03-11

    We report substantially enlarged lateral photovoltaic effect (LPE) in the ZnO/Ag/Si nanostructures. The maximum LPE sensitivity (55.05 mv/mm) obtained in this structure is about seven times larger than that observed in the control sample (7.88 mv/mm) of ZnO/Si. We attribute this phenomenon to the strong localized surface plasmon resonances (LSPRs) induced by nano Ag semicontinuous films. Quite different from the traditional LPE in PN junction type structures, in which light-generated carriers contributed to LPE merely depends on direct excitation of light in semiconductor, this work firstly demonstrates that, by introducing a super thin metal Ag in the interface between two different kinds of semiconductors, the nanoscale Ag embedded in the interface will produce strong resonance of localized field, causing extra intraband excitation, interband excitation and an enhanced direct excitation. As a consequence, these LSPRs dominated contributions harvest much more carriers, giving rise to a greatly enhanced LPE. In particular, this LSPRs-driven mechanism constitutes a sharp contrast to the traditional LPE operation mechanism. This work suggests a brand new LSPRs approach for tailoring LPE-based devices and also opens avenues of research within current photoelectric sensors area.

  11. Emerging giant resonant exciton induced by Ta substitution in anatase TiO2: A tunable correlation effect

    NASA Astrophysics Data System (ADS)

    Yong, Z.; Trevisanutto, P. E.; Chiodo, L.; Santoso, I.; Barman, A. R.; Asmara, T. C.; Dhar, S.; Kotlov, A.; Terentjevs, A.; Della Sala, F.; Olevano, V.; Rübhausen, M.; Venkatesan, T.; Rusydi, A.

    2016-05-01

    Titanium dioxide (TiO2) has rich physical properties with potential implications for both fundamental physics and new applications. To date, the main focus of applied research is to tune its optical properties, which is usually done via doping and/or nanoengineering. However, understanding the role of d electrons in materials and possible functionalization of d -electron properties are still major challenges. Herewith, within a combination of an innovative experimental technique, high-energy optical conductivity, and state-of-the-art ab initio electronic structure calculations, we report an emerging, novel resonant exciton in the deep ultraviolet region of the optical response. The resonant exciton evolves upon low-concentration Ta substitution in anatase TiO2 films. It is surprisingly robust and related to strong electron-electron and electron-hole interactions. The d - and f -orbital localization, due to Ta substitution, plays an unexpected role, activating strong electronic correlations and dominating the optical response under photoexcitation. Our results shed light on a new optical phenomenon in anatase TiO2 films and on the possibility of tuning electronic properties by Ta substitution.

  12. Localized surface plasmon resonances dominated giant lateral photovoltaic effect observed in ZnO/Ag/Si nanostructure.

    PubMed

    Zhang, Ke; Wang, Hui; Gan, Zhikai; Zhou, Peiqi; Mei, Chunlian; Huang, Xu; Xia, Yuxing

    2016-01-01

    We report substantially enlarged lateral photovoltaic effect (LPE) in the ZnO/Ag/Si nanostructures. The maximum LPE sensitivity (55.05 mv/mm) obtained in this structure is about seven times larger than that observed in the control sample (7.88 mv/mm) of ZnO/Si. We attribute this phenomenon to the strong localized surface plasmon resonances (LSPRs) induced by nano Ag semicontinuous films. Quite different from the traditional LPE in PN junction type structures, in which light-generated carriers contributed to LPE merely depends on direct excitation of light in semiconductor, this work firstly demonstrates that, by introducing a super thin metal Ag in the interface between two different kinds of semiconductors, the nanoscale Ag embedded in the interface will produce strong resonance of localized field, causing extra intraband excitation, interband excitation and an enhanced direct excitation. As a consequence, these LSPRs dominated contributions harvest much more carriers, giving rise to a greatly enhanced LPE. In particular, this LSPRs-driven mechanism constitutes a sharp contrast to the traditional LPE operation mechanism. This work suggests a brand new LSPRs approach for tailoring LPE-based devices and also opens avenues of research within current photoelectric sensors area. PMID:26965713

  13. X-ray excited photoluminescence near the giant resonance in solid-solution Gd1-xTbxOCl nanocrystals and their retention upon solvothermal topotactic transformation to Gd1-xTbxF3

    NASA Astrophysics Data System (ADS)

    Waetzig, Gregory R.; Horrocks, Gregory A.; Jude, Joshua W.; Zuin, Lucia; Banerjee, Sarbajit

    2015-12-01

    Design rules for X-ray phosphors are much less established as compared to their optically stimulated counterparts owing to the absence of a detailed understanding of sensitization mechanisms, activation pathways and recombination channels upon high-energy excitation. Here, we demonstrate a pronounced modulation of the X-ray excited photoluminescence of Tb3+ centers upon excitation in proximity to the giant resonance of the host Gd3+ ions in solid-solution Gd1-xTbxOCl nanocrystals prepared by a non-hydrolytic cross-coupling method. The strong suppression of X-ray excited optical luminescence at the giant resonance suggests a change in mechanism from multiple exciton generation to single thermal exciton formation and Auger decay processes. The solid-solution Gd1-xTbxOCl nanocrystals are further topotactically transformed with retention of a nine-coordinated cation environment to solid-solution Gd1-xTbxF3 nanocrystals upon solvothermal treatment with XeF2. The metastable hexagonal phase of GdF3 can be stabilized at room temperature through this topotactic approach and is transformed subsequently to the orthorhombic phase. The fluoride nanocrystals indicate an analogous but blue-shifted modulation of the X-ray excited optical luminescence of the Tb3+ centers upon X-ray excitation near the giant resonance of the host Gd3+ ions.Design rules for X-ray phosphors are much less established as compared to their optically stimulated counterparts owing to the absence of a detailed understanding of sensitization mechanisms, activation pathways and recombination channels upon high-energy excitation. Here, we demonstrate a pronounced modulation of the X-ray excited photoluminescence of Tb3+ centers upon excitation in proximity to the giant resonance of the host Gd3+ ions in solid-solution Gd1-xTbxOCl nanocrystals prepared by a non-hydrolytic cross-coupling method. The strong suppression of X-ray excited optical luminescence at the giant resonance suggests a change in mechanism

  14. Giant Planets

    NASA Astrophysics Data System (ADS)

    Lunine, J. I.

    Beyond the inner solar system's terrestrial planets, with their compact orbits and rock -metal compositions, lies the realm of the outer solar system and the giant planets. Here the distance between planets jumps by an order of magnitude relative to the spacing of the terrestrial planets, and the masses of the giants are one to two orders of magnitude greater than Venus and Earth - the largest terrestrial bodies. Composition changes as well, since the giant planets are largely gaseous, with inferred admixtures of ice, rock, and metal, while the terrestrial planets are essentially pure rock and metal. The giant planets have many more moons than do the terrestrial planets, and the range of magnetic field strengths is larger in the outer solar system. It is the giant planets that sport rings, ranging from the magnificent ones around Saturn to the variable ring arcs of Neptune. Were it not for the fact that only Earth supports abundant life (with life possibly existing, but not proved to exist, in the martian crust and liquid water regions underneath the ice of Jupiter's moon Europa), the terrestrial planets would pale in interest next to the giant planets for any extraterrestrial visitor.

  15. RCNP E398 {sup 16}O,{sup 12}C(p,p’) experiment: Measurement of the γ-ray emission probability from giant resonances in relation to {sup 16}O,{sup 12}C(ν,ν’) reactions

    SciTech Connect

    Ou, I.; Yamada, Y.; Mori, T.; Yano, T.; Sakuda, M.; Tamii, A.; Suzuki, T.; Yosoi, M.; Aoi, N.; Ideguchi, E.; Hashimoto, T.; Miki, K.; Ito, T.; Iwamoto, C.; Yamamoto, T.; Akimune, H.

    2015-05-15

    We propose to measure the γ-ray emission probability from excited states above 5 MeV including giant resonance of {sup 16}O and {sup 12}C as a function of excitation energy in 1-MeV step. Here, we measure both the excitation energy (E{sub x}=5-30MeV) at the forward scattering angles (0°-3°) of the {sup 16}O, {sup 12}C (p, p’) reaction using Grand-Raiden Spectrometer and the energy of γ-rays (E{sub γ}) using an array of NaI(Tl) counters. The purpose of the experiment is to provide the basic and important information not only for the γ-ray production from primary neutral-current neutrino-oxygen (-carbon) interactions but also for that from the secondary hadronic (neutron-oxygen and -carbon) interactions.

  16. 12. PIERS 5S AND 4S, SHOWING TRANSITION AT 4S FROM ...

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

    12. PIERS 5S AND 4S, SHOWING TRANSITION AT 4S FROM GIRDER SPAN TO 'SUSPENDED' TRUSS SPAN AT U0. VIEW LOOKING WEST. - George P. Coleman Memorial Bridge, Spanning York River at U.S. Route 17, Yorktown, York County, VA

  17. Giant Axonal Neuropathy

    MedlinePlus

    ... Diversity Find People About NINDS NINDS Giant Axonal Neuropathy Information Page Table of Contents (click to jump ... done? Clinical Trials Organizations What is Giant Axonal Neuropathy? Giant axonal neuropathy (GAN) is a rare inherited ...

  18. Giant Magnons Meet Giant Gravitons

    SciTech Connect

    Hofman, Diego M.

    2008-07-28

    We study the worldsheet reflection matrix of a string attached to a D-brane in AdS{sub 5}xS{sup 5}. The D-brane corresponds to a maximal giant graviton that wraps an S{sup 3} inside S{sup 5}. In the gauge theory, the open string is described by a spin chain with boundaries. We focus on open strings with a large SO(6) charge and define an asymptotic boundary reflection matrix. Using the symmetries of the problem, we review the computation of the boundary reflection matrix, up to a phase. We also discuss weak and strong coupling computations where we obtain the overall phase factor and test our exact results.

  19. Mass loss in red giants and supergiants

    NASA Technical Reports Server (NTRS)

    Sanner, F.

    1975-01-01

    The circumstellar envelopes surrounding late-type giants and supergiants were studied using high resolution, photoelectric scans of strong optical resonance lines. A method for extracting the circumstellar from the stellar components of the lines allowed a quantitative determination of the physical conditions in the envelopes and the rates of mass loss at various positions in the red giant region of the HR diagram. The observed strengthening of the circumstellar spectrum with increasing luminosity and later spectral type is probably caused by an increase in the mass of the envelopes. The mass loss rate for individual stars is proportional to the visual luminosity; high rates for the supergiants suggest that mass loss is important in their evolution. The bulk of the mass return to the interstellar medium in the red giant region comes from the normal giants, at a rate comparable to that of planetary nebulae.

  20. Search for missing ψ (4 S ) in the e+e-→π+π-ψ (2 S ) process

    NASA Astrophysics Data System (ADS)

    Chen, Dian-Yong; Liu, Xiang; Matsuki, Takayuki

    2016-02-01

    A detailed analysis to find a missing ψ (4 S ) is made by utilizing the recent precise measurements of the cross section for the process e+e-→ψ (2 S )π+π- by Belle. Assuming three resonances Y (4360 ), Y (4660 ), and ψ (4 S ) to fit the data, we obtain the resonance parameters for ψ (4 S ) as m =4243 MeV and Γ =16 ±31 MeV , showing a narrow state as predicted before. A combined fit to the data e+e-→ψ (2 S )π+π- , hcπ+π- , and χc 0ω is also performed to obtain the similar resonance parameters of ψ (4 S ). The upper limit of the branching ratio is fitted to be B (ψ (4 S )→ψ (2 S )π+π-)<3 ×10-3, which can be understood by hadronic loop contributions within a reasonable range of parameters. In addition, the ratios of the branching ratios of the ψ (4 S ) dipion transition to that of ψ (4 S )→χc 0ω are fitted, which can be further measured by BESIII and the forthcoming BelleII to confirm the existence of ψ (4 S ).

  1. YOUNG SOLAR SYSTEM's FIFTH GIANT PLANET?

    SciTech Connect

    Nesvorny, David

    2011-12-15

    Studies of solar system formation suggest that the solar system's giant planets formed and migrated in the protoplanetary disk to reach the resonant orbits with all planets inside {approx}15 AU from the Sun. After the gas disk's dispersal, Uranus and Neptune were likely scattered by the gas giants, and approached their current orbits while dispersing the transplanetary disk of planetesimals, whose remains survived to this time in the region known as the Kuiper Belt. Here we performed N-body integrations of the scattering phase between giant planets in an attempt to determine which initial states are plausible. We found that the dynamical simulations starting with a resonant system of four giant planets have a low success rate in matching the present orbits of giant planets and various other constraints (e.g., survival of the terrestrial planets). The dynamical evolution is typically too violent, if Jupiter and Saturn start in the 3:2 resonance, and leads to final systems with fewer than four planets. Several initial states stand out in that they show a relatively large likelihood of success in matching the constraints. Some of the statistically best results were obtained when assuming that the solar system initially had five giant planets and one ice giant, with the mass comparable to that of Uranus and Neptune, and which was ejected to interstellar space by Jupiter. This possibility appears to be conceivable in view of the recent discovery of a large number of free-floating planets in interstellar space, which indicates that planet ejection should be common.

  2. Recurrent renal giant leiomyosarcoma.

    PubMed

    Öziş, Salih Erpulat; Gülpınar, Kamil; Şahlı, Zafer; Konak, Baha Burak; Keskin, Mete; Özdemir, Süleyman; Ataoğlu, Ömür

    2016-01-01

    Primary renal leiomyosarcomas are rare, aggressive tumors. They constitute 1-2% of adult malignant renal tumors. Although leiomyosarcomas are the most common histological type (50-60%) of renal sarcomas, information on renal leiomyosarcoma is limited. Local or systemic recurrences are common. The radiological appearance of renal leiomyosarcomas is not specific, therefore renal leiomyosarcoma cannot be distinguished from renal cell carcinoma by imaging methods in all patients. A 74-year-old female patient presented to our clinic complaining of a palpable mass on the right side of her abdomen in November 2012. The abdominal magnetic resonance imaging revealed a mass, 25 × 24 × 23 cm in size. Her past medical history revealed that she has undergone right radical nephrectomy in 2007, due to a 11 × 12 × 13 cm renal mass that was then reported as renal cell carcinoma on abdominal magnetic resonance imaging, but the pathological diagnosis was low-grade renal leiomyosarcoma. The most recent follow-up of the patient was in 2011, with no signs of local recurrence or distant metastases within this four-year period. The patient underwent laparotomy on November 2012, and a 35 cm retroperitoneal mass was excised. The pathological examination of the mass was reported as high-grade leiomyosarcoma. The formation of this giant retroperitoneal mass in 1 year can be explained by the transformation of the lesion's pathology from low-grade to a high-grade tumor. PMID:27436926

  3. Transforming giants.

    PubMed

    Kanter, Rosabeth Moss

    2008-01-01

    Large corporations have long been seen as lumbering, inflexible, bureaucratic--and clueless about global developments. But recently some multinationals seem to be transforming themselves: They're engaging employees, moving quickly, and introducing innovations that show true connection with the world. Harvard Business School's Kanter ventured with a research team inside a dozen global giants--including IBM, Procter & Gamble, Omron, CEMEX, Cisco, and Banco Real--to discover what has been driving the change. After conducting more than 350 interviews on five continents, she and her colleagues came away with a strong sense that we are witnessing the dawn of a new model of corporate power: The coordination of actions and decisions on the front lines now appears to stem from widely shared values and a sturdy platform of common processes and technology, not from top-down decrees. In particular, the values that engage the passions of far-flung workforces stress openness, inclusion, and making the world a better place. Through this shift in what might be called their guidance systems, the companies have become as creative and nimble as much smaller ones, even while taking on social and environmental challenges of a scale that only large enterprises could attempt. IBM, for instance, has created a nonprofit partnership, World Community Grid, through which any organization or individual can donate unused computing power to research projects and see what is being done with the donation in real time. IBM has gained an inspiring showcase for its new technology, helped business partners connect with the company in a positive way, and offered individuals all over the globe the chance to contribute to something big.

  4. Giant congenital nevus

    MedlinePlus

    ... pigmented nevus; Giant hairy nevus; Giant pigmented nevus; Bathing trunk nevus; Congenital melanocytic nevus - large ... baby grows in the womb. In some families bathing trunk nevi may be inherited. The condition may ...

  5. Giant Cell Arteritis

    MedlinePlus

    Giant cell arteritis is a disorder that causes inflammation of your arteries, usually in the scalp, neck, and arms. ... arteries, which keeps blood from flowing well. Giant cell arteritis often occurs with another disorder called polymyalgia ...

  6. Giant impacts on giant planets

    NASA Astrophysics Data System (ADS)

    de Pater, Imke

    2014-10-01

    The 2009 impact and recent superbolides on Jupiter caught the world by surprise and cast doubt on impactor flux estimates for the outer solar system. Enhanced amateur planetary imaging techniques yield both high spatial resolution (enabling the 2009 impact debris field detection) and rapid frame rates (enabling the 2010/2012 impact flash detections and lightcurve measurements).We propose a ToO program to image future impacts on Jupiter and Saturn. To remove the possibility of impact cloud non-detections, the program will be triggered only if an existing impact debris field is seen, an object on a collision course with Jupiter or Saturn is discovered, or an impact light curve is measured with an estimated total energy large enough to generate an impact cloud in a giant planet atmosphere (10^20 J).HST provides the only way to image these events in the ultraviolet, providing information on aerosol altitudes and on smaller particles that are less visible to ground-based infrared observations. High-resolution imaging with proper timing (not achievable from the ground) is required to measure precisely both the velocity fields of impact sites and the optical spectrum of impact debris. HST observations of past impacts on Jupiter have also served both as cornerstones of science investigations at other wavelengths and as vehicles for effective public outreach.Large outer solar system impacts are governed by the same physics as in the terrestrial events that dominate the impact threat to humans. Studying the behavior of impactors of various sizes and compositions, as they enter the atmosphere at varying angles and speeds, will better quantify terrestrial impact hazards.

  7. Giant impacts on giant planets

    NASA Astrophysics Data System (ADS)

    de Pater, Imke

    2013-10-01

    The 2009 impact and recent superbolides on Jupiter caught the world by surprise and cast doubt on impactor flux estimates for the outer solar system. Enhanced amateur planetary imaging techniques yield both high spatial resolution {enabling the 2009 impact debris field detection} and rapid frame rates {enabling the 2010/2012 impact flash detections and lightcurve measurements}.We propose a ToO program to image future impacts on Jupiter and Saturn. To remove the possibility of impact cloud non-detections, the program will be triggered only if an existing impact debris field is seen, an object on a collision course with Jupiter or Saturn is discovered, or an impact light curve is measured with an estimated total energy large enough to generate an impact cloud in a giant planet atmosphere {10^20 J}.HST provides the only way to image these events in the ultraviolet, providing information on aerosol altitudes and on smaller particles that are less visible to ground-based infrared observations. High-resolution imaging with proper timing {not achievable from the ground} is required to measure precisely both the velocity fields of impact sites and the optical spectrum of impact debris. HST observations of past impacts on Jupiter have also served both as cornerstones of science investigations at other wavelengths and as vehicles for effective public outreach.Large outer solar system impacts are governed by the same physics as in the terrestrial events that dominate the impact threat to humans. Studying the behavior of impactors of various sizes and compositions, as they enter the atmosphere at varying angles and speeds, will better quantify terrestrial impact hazards.

  8. Macroscopic resonances in planar geometry

    NASA Astrophysics Data System (ADS)

    Strutinsky, V.; Vydrug-Vlasenko, S.; Magner, A.

    1987-09-01

    Resonating response is a characteristic feature of free-particle system contained between two vibrating planar surfaces. Resonance frequencies and widths are determined by a mean period of motion of particles reflected from the walls. Resonances due to quasiperiodic macroscopic motion appear when the interaction among quasi-particles by means of perturbations of the common self-consistent field is included. They have finite widths corresponding to collisionless Landau dissipation. Possible relationship of this phenomenon to nuclear giant resonances is discussed.

  9. Electron Excitation Cross Sections for the 2s(sup 2)2p(sup 3) (sup 4)S -> 2s(sup 2)2p(sup 3) (sup 2d) ->2s2p(sup 4) (sup 4p) (Resonance) Transitions in Oil

    NASA Technical Reports Server (NTRS)

    Zuo, M.; Smith, S.; Chutjian, A.; Williams, I.; Tayal, S.; McLaughlin, B.

    1994-01-01

    Experimental and theoretical excitation cross sections are reported for the first forbidden transition xxx and the first allowed (resonance) transition xxx in OII. Use is made of electron-energy loss and merged beams methods. The electron energy range covered is 3.33 eV (threshold) to 15 eV for the S->D transition, and 14.9 eV (threshold) to 40 eV for the S->P transition. Care was taken to assess and minimize the metastable fraction of the OII beam. An electron mirror was designed and tested to reflect inelastically back-scattered electrons into the forward direction to account for the full range of polar scattering angles. Comparisons are made between present experiments and 11-state R-Matrix calculations. Calculations are also presented for the xxx transition.

  10. Nqrs Data for C8H8Cl3N3O4S2 (Subst. No. 1087)

    NASA Astrophysics Data System (ADS)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume A `Substances Containing Ag … C10H15' of Volume 48 `Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III `Condensed Matter'. It contains an extract of Section `3.2 Data tables' of the Chapter `3 Nuclear quadrupole resonance data' providing the NQRS data for C8H8Cl3N3O4S2 (Subst. No. 1087)

  11. Giant optical nonlinearity of plasmonic nanostructures

    SciTech Connect

    Melentiev, P N; Afanasev, A E; Balykin, V I

    2014-06-30

    The experimental studies of giant optical nonlinearity of single metal nanostructures are briefly reviewed. A new hybrid nanostructure – split-hole resonator (SHR) – is investigated. This structure is characterised by a record-high efficiency of third-harmonic generation and multiphoton luminescence (its nonlinearity exceeds that of a single nanohole by five orders of magnitude) and an unprecedently high sensitivity to light polarisation (extinction coefficient 4 × 10{sup 4}). (extreme light fields and their applications)

  12. Measurement of the branching fraction of Gamma(4S) --> B0B0.

    PubMed

    Aubert, B; Barate, R; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges-Pous, E; Palano, A; Pappagallo, M; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Chevalier, N; Cottingham, W N; Kelly, M P; Cuhadar-Donszelmann, T; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Thiessen, D; Khan, A; Kyberd, P; Teodorescu, L; Blinov, A E; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bondioli, M; Bruinsma, M; Chao, M; Eschrich, I; Kirkby, D; Lankford, A J; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Weinstein, A J R; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; Del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, Sh; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Blanc, F; Bloom, P; Chen, S; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Ruddick, W O; Smith, J G; Ulmer, K A; Zhang, J; Chen, A; Eckhart, E A; Harton, J L; Soffer, A; Toki, W H; Wilson, R J; Zeng, Q; Spaan, B; Altenburg, D; Brandt, T; Brose, J; Dickopp, M; Feltresi, E; Hauke, A; Lacker, H M; Maly, E; Nogowski, R; Otto, S; Petzold, A; Schott, G; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Bernard, D; Bonneaud, G R; Grenier, P; Schrenk, S; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Bard, D J; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Xie, Y; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Marks, J; Uwer, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Gaillard, J R; Morton, G W; Nash, J A; Nikolich, M B; Taylor, G P; Charles, M J; Grenier, G J; Mallik, U; Cochran, J; Crawley, H B; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Yi, J; Arnaud, N; Davier, M; Giroux, X; Grosdidier, G; Höcker, A; Le Diberder, F; Lepeltier, V; Lutz, A M; Petersen, T C; Pierini, M; Plaszczynski, S; Rodier, S; Roudeau, P; Schune, M H; Stocchi, A; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Chavez, C A; Coleman, J P; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Parry, R J; Payne, D J; Touramanis, C; Cormack, C M; Di Lodovico, F; Brown, C L; Cowan, G; Flack, R L; Flaecher, H U; Green, M G; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hodgkinson, M C; Lafferty, G D; Naisbit, M T; Williams, J C; Chen, C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Staengle, H; Willocq, S; Cowan, R; Koeneke, K; Sciolla, G; Sekula, S J; Taylor, F; Yamamoto, R K; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Taras, P; Nicholson, H; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Snoek, H L; Wilden, L; Jessop, C P; Losecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Rahimi, A M; Ter-Antonyan, R; Wong, Q K; Brau, J; Frey, R; Igonkina, O; Lu, M; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; John, M J J; Leruste, Ph; Malclès, J; Ocariz, J; Roos, L; Therin, G; Behera, P K; Gladney, L; Guo, Q H; Panetta, J; Biasini, M; Covarelli, R; Pioppi, M; Angelini, C; Batignani, G; Bettarini, S; Bucci, F; Calderini, G; Carpinelli, M; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Simi, G; Walsh, J; Haire, M; Judd, D; Paick, K; Wagoner, D E; Danielson, N; Elmer, P; Lau, Y P; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Bellini, F; Cavoto, G; D'Orazio, A; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Tehrani, F Safai; Voena, C; Christ, S; Schröder, H; Wagner, G; Waldi, R; Adye, T; De Groot, N; Franek, B; Gopal, G P; Olaiya, E O; Wilson, F F; Aleksan, R; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P-F; Graziani, G; de Monchenault, G Hamel; Kozanecki, W; Legendre, M; London, G W; Mayer, B; Vasseur, G; Yèche, Ch; Zito, M; Purohit, M V; Weidemann, A W; Wilson, J R; Yumiceva, F X; Abe, T; Allen, M; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmueller, O L; Claus, R; Convery, M R; Cristinziani, M; Dingfelder, J C; Dong, D; Dorfan, J; Dujmic, D; Dunwoodie, W; Fan, S; Field, R C; Glanzman, T; Gowdy, S J; Hadig, T; Halyo, V; Hast, C; Hryn'ova, T; Innes, W R; Kelsey, M H; Kim, P; Kocian, M L; Leith, D W G S; Libby, J; Luitz, S; Luth, V; Lynch, H L; Marsiske, H; Messner, R; Mohapatra, A K; Muller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Soha, A; Stelzer, J; Strube, J; Su, D; Sullivan, M K; Thompson, J; Va'vra, J; Wagner, S R; Weaver, M; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Young, C C; Burchat, P R; Edwards, A J; Majewski, S A; Petersen, B A; Roat, C; Ahmed, M; Ahmed, S; Alam, M S; Ernst, J A; Saeed, M A; Saleem, M; Wappler, F R; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Kim, H; Ritchie, J L; Satpathy, A; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Bona, M; Gallo, F; Gamba, D; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Ricca, G Della; Dittongo, S; Grancagnolo, S; Lanceri, L; Poropat, P; Vitale, L; Vuagnin, G; Martinez-Vidal, F; Panvini, R S; Banerjee, Sw; Bhuyan, B; Brown, C M; Fortin, D; Hamano, K; Jackson, P D; Kowalewski, R; Roney, J M; Sobie, R J; Back, J J; Harrison, P F; Latham, T E; Mohanty, G B; Band, H R; Chen, X; Cheng, B; Dasu, S; Datta, M; Eichenbaum, A M; Flood, K T; Graham, M; Hollar, J J; Johnson, J R; Kutter, P E; Li, H; Liu, R; Mellado, B; Mihalyi, A; Pan, Y; Prepost, R; Tan, P; von Wimmersperg-Toeller, J H; Wu, J; Wu, S L; Yu, Z; Greene, M G; Neal, H

    2005-07-22

    We report the first measurement of the branching fraction f(00) for Gamma(4S) --> B(0)B(0). The data sample consists of 81.7 fb(-1) collected at the Gamma(4S) resonance with the BABAR detector at the SLAC PEP-II asymmetric-energy e(+)e(-) storage ring. Using partial reconstruction of the decay B(0) --> D(*+) l(-)nu(l) in which only the charged lepton and the soft pion from the decay D(*+) --> D(0)pi(+) are reconstructed, we obtain f(00) = 0.487 +/- 0.010(stat) +/- 0.008(syst). Our result does not depend on the branching fractions of B(0) --> D(*+)l(-)nu(l) and D(*+) --> D(0)pi(+) decays, on the ratio of the charged and neutral B meson lifetimes, nor on the assumption of isospin symmetry.

  13. Observation of e+e-→χc 0ω and missing higher charmonium ψ (4 S )

    NASA Astrophysics Data System (ADS)

    Chen, Dian-Yong; Liu, Xiang; Matsuki, Takayuki

    2015-05-01

    Stimulated by the recent BESIII observation of a new resonance in e+e-→ω χc 0 which is consistent with our predicted ψ (4 S ), we estimate the meson loop contribution to ψ (4 S )→ω χc 0 in this work. The evaluation indicates that our theoretical estimate can overlap with the experimental data in a reasonable parameter range. This fact shows that introduction of the missing higher charmonium ψ (4 S ) provides a possible explanation to the recent BESIII observation. The upper limit of a branching ratio of ψ (4 S )→η J /ψ is also predicted to be 1.9 ×10-3 , which can be further tested by BESIII, Belle, and forthcoming BelleII.

  14. Unstable giant gravitons

    SciTech Connect

    Mello Koch, Robert de; Ives, Norman; Smolic, Jelena; Smolic, Milena

    2006-03-15

    We find giant graviton solutions in Frolov's three parameter generalization of the Lunin-Maldacena background. The background we study has {gamma}-tilde{sub 1}=0 and {gamma}-tilde{sub 2}={gamma}-tilde{sub 3}={gamma}-tilde. This class of backgrounds provides a nonsupersymmetric example of the gauge theory/gravity correspondence that can be tested quantitatively, as recently shown by Frolov, Roiban, and Tseytlin. The giant graviton solutions we find have a greater energy than the point gravitons, making them unstable states. Despite this, we find striking quantitative agreement between the gauge theory and gravity descriptions of open strings attached to the giant.

  15. The Giant Cell.

    ERIC Educational Resources Information Center

    Stockdale, Dennis

    1998-01-01

    Provides directions for the construction of giant plastic cells, including details for building and installing the organelles. Also contains instructions for preparing the ribosomes, nucleolus, nucleus, and mitochondria. (DDR)

  16. The Next Giant Step

    NASA Video Gallery

    Artist Robert McCall painted "The Next Giant Step" in 1979 to commemorate the heroism and courage of spaceflight pioneers. Located in the lobby of Johnson's building 2, the mural depicts America's ...

  17. N(4S) formation following the 193.3-nm ArF laser irradiation of NO and NO2 and its application to kinetic studies of N(4S) reactions with NO and NO2.

    PubMed

    Nakayama, Tomoki; Takahashi, Kenshi; Matsumi, Yutaka; Shibuya, Kazuhiko

    2005-12-01

    Formation of the ground-state nitrogen atom, N((4)S), following 193.3-nm ArF laser irradiation of NO and NO(2) was detected directly by a technique of laser-induced fluorescence (LIF) spectroscopy at 120.07 nm. Tunable vacuum ultraviolet (VUV) laser radiation around 120.07 nm was generated by two-photon resonance four-wave sum frequency mixing in Hg vapor. Photoexcitation processes of NO and NO(2) giving rise to the N((4)S) formation are discussed on the basis of the Doppler profiles of the nascent N((4)S) atoms produced from the photolysis of NO and NO(2) and the photolysis laser-power dependence of the N((4)S) signal intensities. Using laser flash photolysis and vacuum ultraviolet laser-induced fluorescence detection, the kinetics of the reactions of N((4)S) with NO and NO(2) have been investigated at 295 +/- 2 K. The rate constants for the reactions of N((4)S) with NO and NO(2) were determined to be (3.8 +/- 0.2) x 10(-11) and (7.3 +/- 0.9) x 10(-12) cm(3) molecule(-1) s(-1), respectively, where the quoted uncertainties are 2sigma statistical uncertainty including estimated systematic error.

  18. Giant congenital melanocytic nevus.

    PubMed

    Viana, Ana Carolina Leite; Gontijo, Bernardo; Bittencourt, Flávia Vasques

    2013-01-01

    Giant congenital melanocytic nevus is usually defined as a melanocytic lesion present at birth that will reach a diameter ≥ 20 cm in adulthood. Its incidence is estimated in <1:20,000 newborns. Despite its rarity, this lesion is important because it may associate with severe complications such as malignant melanoma, affect the central nervous system (neurocutaneous melanosis), and have major psychosocial impact on the patient and his family due to its unsightly appearance. Giant congenital melanocytic nevus generally presents as a brown lesion, with flat or mammilated surface, well-demarcated borders and hypertrichosis. Congenital melanocytic nevus is primarily a clinical diagnosis. However, congenital nevi are histologically distinguished from acquired nevi mainly by their larger size, the spread of the nevus cells to the deep layers of the skin and by their more varied architecture and morphology. Although giant congenital melanocytic nevus is recognized as a risk factor for the development of melanoma, the precise magnitude of this risk is still controversial. The estimated lifetime risk of developing melanoma varies from 5 to 10%. On account of these uncertainties and the size of the lesions, the management of giant congenital melanocytic nevus needs individualization. Treatment may include surgical and non-surgical procedures, psychological intervention and/or clinical follow-up, with special attention to changes in color, texture or on the surface of the lesion. The only absolute indication for surgery in giant congenital melanocytic nevus is the development of a malignant neoplasm on the lesion.

  19. Giant colon diverticulum.

    PubMed

    Chater, C; Saudemont, A; Zerbib, P

    2015-11-01

    Giant colonic diverticulum is defined by a diverticulum whose diameter is greater than 4 cm. This is a rare entity, arising mainly in the sigmoid colon. The diagnosis is based on abdominal computed tomography that shows a gas-filled structure communicating with the adjacent colon, with a smooth, thin diverticular wall that does not enhance after injection of contrast. Surgical treatment is recommended even in asymptomatic diverticula, due to the high prevalence and severity of complications. The gold standard treatment is segmental colectomy. Some authors propose a diverticulectomy when the giant diverticulum is unique.

  20. Atrial fibrillation detection using an iPhone 4S.

    PubMed

    Lee, Jinseok; Reyes, Bersain A; McManus, David D; Maitas, Oscar; Mathias, Oscar; Chon, Ki H

    2013-01-01

    Atrial fibrillation (AF) affects three to five million Americans and is associated with significant morbidity and mortality. Existing methods to diagnose this paroxysmal arrhythmia are cumbersome and/or expensive. We hypothesized that an iPhone 4S can be used to detect AF based on its ability to record a pulsatile photoplethysmogram signal from a fingertip using the built-in camera lens. To investigate the capability of the iPhone 4S for AF detection, we first used two databases, the MIT-BIH AF and normal sinus rhythm (NSR) to derive discriminatory threshold values between two rhythms. Both databases include RR time series originating from 250 Hz sampled ECG recordings. We rescaled the RR time series to 30 Hz so that the RR time series resolution is 1/30 (s) which is equivalent to the resolution from an iPhone 4S. We investigated three statistical methods consisting of the root mean square of successive differences (RMSSD), the Shannon entropy (ShE) and the sample entropy (SampE), which have been proved to be useful tools for AF assessment. Using 64-beat segments from the MIT-BIH databases, we found the beat-to-beat accuracy value of 0.9405, 0.9300, and 0.9614 for RMSSD, ShE, and SampE, respectively. Using an iPhone 4S, we collected 2-min pulsatile time series from 25 prospectively recruited subjects with AF pre- and postelectrical cardioversion. Using derived threshold values of RMSSD, ShE and SampE from the MIT-BIH databases, we found the beat-to-beat accuracy of 0.9844, 0.8494, and 0.9522, respectively. It should be recognized that for clinical applications, the most relevant objective is to detect the presence of AF in the data. Using this criterion, we achieved an accuracy of 100% for both the MIT-BIH AF and iPhone 4S databases.

  1. Analogs of the giant dipole and spin-dipole resonances in {sup 4}He and in {alpha} clusters of {sup 6,7}Li studied by the {sup 4}He,{sup 6,7}Li({sup 7}Li,{sup 7}Be{gamma}) reactions

    SciTech Connect

    Nakayama, S.; Matsumoto, E.; Fushimi, K.; Hayami, R.; Kawasuso, H.; Yasuda, K.; Yamagata, T.; Akimune, H.; Ikemizu, H.; Asaji, S.; Ishida, T.; Kudoh, T.; Sagara, K.; Fujiwara, M.; Hashimoto, H.; Kawase, K.; Nakanishi, K.; Oota, T.; Yosoi, M.; Greenfield, M. B.

    2008-07-15

    We studied analogs of the giant dipole resonance (GDR) and spin-dipole resonance (SDR) in {sup 4}He and in the {alpha} clusters of {sup 6,7}Li via the ({sup 7}Li,{sup 7}Be{gamma}) reactions on {sup 4}He, {sup 6}Li, and {sup 7}Li at an incident energy of 455 MeV and at a scattering angle of 0 deg. by measuring spin-nonflip and spin-flip spectra. The reaction Q-values for the analogs of the GDR and SDR in the {alpha} clusters of {sup 6,7}Li were found to be more negative than those in {sup 4}He by 2.0{+-}0.5 MeV. The ratios of the cross section for the analog of the GDR to that for the analog of the SDR in {sup 4}He and in the {alpha} clusters of {sup 6}Li and {sup 7}Li were found to be the same within errors, 0.5{+-}0.1. The cross sections for the analogs of the GDR as well as those for the analogs of the SDR in the {alpha} clusters of {sup 6,7}Li were 0.6{approx}0.8 times smaller than those in {sup 4}He. These results suggest that excitations of {alpha} clusters embedded in nuclei are suppressed as compared with excitations of free {alpha} particles.

  2. Axoplasmic RNA species synthesized in the isolated squid giant axon.

    PubMed

    Rapallino, M V; Cupello, A; Giuditta, A

    1988-07-01

    Isolated squid stellate nerves and giant fiber lobes were incubated for 8 hr in Millipore filtered sea water containing [3H]uridine. The electrophoretic patterns of radioactive RNA purified from the axoplasm of the giant axon and from the giant fiber lobe (cell bodies of the giant axon) demonstrated the presence of RNA species with mobilities corresponding to tRNA and rRNA. The presence of labeled rRNAs was confirmed by the behavior of the large rRNA component (31S) which, in the squid, readily dissociates into its two constituent moyeties (17S and 20S). Comparable results were obtained with the axonal sheath and the stellate nerve. In all the electrophoretic patterns, additional species of radioactive RNA migrated between the 4S and the 20S markers, i.e. with mobilities corresponding to presumptive mRNAs. Chromatographic analysis of the purified RNAs on oligo(dT)cellulose indicated the presence of labeled poly(A)+ RNA in all tissue samples. Radioactive poly(A)+ RNA represented approximately 1% of the total labeled RNA in the axoplasm, axonal sheath and stellate nerve, but more than 2% in the giant fiber lobe. The labeled poly(A)+ RNAs of the giant fibre lobe showed a prevalence of larger species in comparison to the axonal sheath and stellate nerve. In conclusion, the axoplasmic RNAs synthesized by the isolated squid giant axon appear to include all the major classes of axoplasmic RNAs, that is rRNA, tRNA and mRNA.

  3. Management of giant pseudomeningoceles after spinal surgery

    PubMed Central

    2010-01-01

    Background Pseudomeningoceles are a rare complication after spinal surgery, and studies on these complex formations are few. Methods Between October 2000 and March 2008, 11 patients who developed symptomatic pseudomeningoceles after spinal surgery were recruited. In this retrospective study, we reported our experiences in the management of these complex, symptomatic pseudomeningoceles after spinal surgery. A giant pseudomeningocele was defined as a pseudomeningocele >8 cm in length. We also evaluated the risk factors for the formation of giant pseudomeningoceles. Results All patients were treated successfully with a combined treatment protocol of open revision surgery for extirpation of the pseudomeningoceles, repair of dural tears, and implantation of a subarachnoid catheter for drainage. Surgery-related complications were not observed. Recurrence of pseudomeningocele was not observed for any patient at a mean follow-up of 16.5 months. This result was confirmed by magnetic resonance imaging. Conclusions We conclude that a combined treatment protocol involving open revision surgery for extirpation of pseudomeningoceles, repair of dural tears, and implantation of a subarachnoid catheter for drainage is safe and effective to treat giant pseudomeningoceles. PMID:20302667

  4. Resonance charge transfer, transport cross sections, and collision integrals for N(+)(3P)-N(4S0) and O(+)(4S0)-O(3P) interactions

    NASA Technical Reports Server (NTRS)

    Stallcop, James R.; Partridge, Harry; Levin, Eugene

    1991-01-01

    N2(+) and O2(+) potential energy curves have been constructed by combining measured data with the results from electronic structure calculations. These potential curves have been employed to determine accurate charge exchange cross sections, transport cross sections, and collision integrals for ground state N(+)-N and O(+)-O interactions. The cross sections have been calculated from a semiclassical approximation to the scattering using a computer code that fits a spline curve through the discrete potential data and incorporates the proper long-range behavior of the interactions forces. The collision integrals are tabulated for a broad range of temperatures 250-100,000 K and are intended to reduce the uncertainty in the values of the transport properties of nonequilibrium air, particularly at high temperatures.

  5. Giant intrathyroidal parathyroid adenoma

    PubMed Central

    Vilallonga, Ramon; Zafón, Carlos; Migone, Raul; Baena, Juan Antonio

    2012-01-01

    Primary hyperparathyroidism (PHPT) is not an uncommon endocrine disorder. However, acute primary hyperparathyroidism, or parathyroid crisis (PC), is a rare clinical entity characterized by life-threatening hypercalcemia of a sudden onset in patients with PHPT. We describe a patient with PC who presented with acute worsening of depressive symptoms, nausea and vomiting, and required emergency surgery. Serum calcium, alkaline phosphatase, and parathyroid hormone were elevated and serum phosphorus was low. An emergency hemithyroidectomy was performed because of none medical control of hypercalcemia. A giant intrathyroidal parathyroid adenoma was diagnosed. PHTP can be a life-threatening situation for patients, requiring immediate surgical treatment. A giant intrathyroidal parathyroid adenoma is an uncommon cause of PC. PMID:22787355

  6. Giant cell arteritis

    PubMed Central

    Calvo-Romero, J

    2003-01-01

    Giant cell arteritis (GCA), temporal arteritis or Horton's arteritis, is a systemic vasculitis which involves large and medium sized vessels, especially the extracranial branches of the carotid arteries, in persons usually older than 50 years. Permanent visual loss, ischaemic strokes, and thoracic and abdominal aortic aneurysms are feared complications of GCA. The treatment consists of high dose steroids. Mortality, with a correct treatment, in patients with GCA seems to be similar that of controls. PMID:13679546

  7. Giant thymic carcinoid.

    PubMed

    John, L C; Hornick, P; Lang, S; Wallis, J; Edmondson, S J

    1991-05-01

    Thymic carcinoid is a rare tumour. It may present with ectopic endocrine secretion or with symptoms of compression as a result of its size. A case is reported which presented with symptoms of compression where the size of the tumour was uniquely large such as to warrant the term giant thymic carcinoid. The typical histological features are described, together with its possible origin and its likely prognosis.

  8. Ice Giant Exploration

    NASA Astrophysics Data System (ADS)

    Rymer, A. M.; Arridge, C. S.; Masters, A.; Turtle, E. P.; Simon, A. A.; Hofstadter, M. D.; Turrini, D.; Politi, R.

    2015-12-01

    The Ice Giants in our solar system, Uranus and Neptune, are fundamentally different from their Gas Giant siblings Jupiter and Saturn, from the different proportions of rock and ice to the configuration of their planetary magnetic fields. Kepler space telescope discoveries of exo-planets indicate that planets of this type are among the most ubiquitous universally and therefore a future mission to explore the nature of the Ice Giants in our own solar system will provide insights into the nature of extra-solar system objects in general. Uranus has the smallest self- luminosity of all the planets, potentially related to catastrophic events early in the planet's history, which also may explain Uranus' large obliquity. Uranus' atmosphere is subject to extreme seasonal forcing making it unique in the Solar System. Neptune is also unique in a number of ways, notably its large moon Triton which is likely a captured Kuiper Belt Object and one of only two moons in the solar system with a robustly collisional atmosphere. Similar to Uranus, the angle between the solar wind and the magnetic dipole axis is subject to large-amplitude variations on both diurnal and seasonal timescales, but peculiarly it has one of the quietest magnetospheres of the solar system, at least according to Voyager 2, the only spacecraft to encounter Neptune to date. A comprehensive mission, as advocated in the Decadal Survey, would provide enormous science return but is also challenging and expensive. In this presentation we will discuss mission scenarios and suggest how collaboration between disciplines and internationally can help us to pursue a mission that includes Ice Giant exploration.

  9. Organising evidence for environmental management decisions: a '4S' hierarchy.

    PubMed

    Dicks, Lynn V; Walsh, Jessica C; Sutherland, William J

    2014-11-01

    Making decisions informed by the best-available science is an objective for many organisations managing the environment or natural resources. Yet, available science is still not widely used in environmental policy and practice. We describe a '4S' hierarchy for organising relevant science to inform decisions. This hierarchy has already revolutionised clinical practice. It is beginning to emerge for environmental management, although all four levels need substantial development before environmental decision-makers can reliably and efficiently find the evidence they need. We expose common bypass routes that currently lead to poor or biased representation of scientific knowledge. We argue that the least developed level of the hierarchy is that closest to decision-makers, placing synthesised scientific knowledge into environmental decision support systems.

  10. Organising evidence for environmental management decisions: a '4S' hierarchy.

    PubMed

    Dicks, Lynn V; Walsh, Jessica C; Sutherland, William J

    2014-11-01

    Making decisions informed by the best-available science is an objective for many organisations managing the environment or natural resources. Yet, available science is still not widely used in environmental policy and practice. We describe a '4S' hierarchy for organising relevant science to inform decisions. This hierarchy has already revolutionised clinical practice. It is beginning to emerge for environmental management, although all four levels need substantial development before environmental decision-makers can reliably and efficiently find the evidence they need. We expose common bypass routes that currently lead to poor or biased representation of scientific knowledge. We argue that the least developed level of the hierarchy is that closest to decision-makers, placing synthesised scientific knowledge into environmental decision support systems. PMID:25280588

  11. Resonances and resonance widths

    SciTech Connect

    Collins, T.

    1986-05-01

    Two-dimensional betatron resonances are much more important than their simple one-dimensional counterparts and exhibit a strong dependence on the betatron phase advance per cell. A practical definition of ''width'' is expanded upon in order to display these relations in tables. A primarily pedagogical introduction is given to explain the tables, and also to encourage a wider capability for deriving resonance behavior and wider use of ''designer'' resonances.

  12. Calculation of the energy loss for an electron passing near giant fullerenes

    NASA Astrophysics Data System (ADS)

    Henrard, L.; Lambin, Ph

    1996-11-01

    We present a theoretical analysis of the electron energy-loss spectra of isolated giant fullerenes. We use a macroscopic dielectric description of spherical onion-like fullerenes and a discrete dipole approximation (DDA) framework for tubular fullerenes. In the DDA model, an anisotropic dynamical polarizability is assigned to each carbon site. We stress the fundamental importance of the hollow character of giant fullerenes in the electron energy-loss resonances.

  13. OMAC4S- Open Modular Avionics for Space Applications

    NASA Astrophysics Data System (ADS)

    Herpel, H.-J.; Willich, G.; Vogel, T.; Schuettauf, A.; Pletner, S.; Schoen, F.; Fidi, C.; Loetzke, M.; Dittrich, L.; Schuelke, P.; Wolf, T.

    2013-08-01

    Today's spacecraft avionics architecture is characterised by a broad variety of processing modules, operating systems and interfaces for exchanging data between different processing modules. The software that implements most of the satellite functionality has to deal with this fact and is one of the reasons why software has become one of the major cost drivers in satellite projects. Similar problems have triggered developments in other industrial domains like AUTOSAR in the automotive area or Integrated Modular Architecture (IMA) in the aerospace industry [8]. All these initiatives are based on the definition of standards for computing platforms and the interfaces between these platforms. The goals of the Open Modular Avionics Architecture for Space Applications (OMAC4S) initiative started by Astrium, Fraunhofer FOKUS, STI, SYSGO and TTTech are to outline a solution that helps to reduce complexity and costs for space avionics significantly. This initiative is partly funded by the German national space agency (DLR) through the project On-Board Computer System Architecture (OBC-SA). In this paper we describe how standardization and the usage of already proven technologies from other industrial domains will help to limit the effect of the software development on schedule and costs of satellite projects. In addition we will demonstrate a migration path to make these technologies available for space applications.

  14. Imaging Extrasolar Giant Planets

    NASA Astrophysics Data System (ADS)

    Bowler, Brendan P.

    2016-10-01

    High-contrast adaptive optics (AO) imaging is a powerful technique to probe the architectures of planetary systems from the outside-in and survey the atmospheres of self-luminous giant planets. Direct imaging has rapidly matured over the past decade and especially the last few years with the advent of high-order AO systems, dedicated planet-finding instruments with specialized coronagraphs, and innovative observing and post-processing strategies to suppress speckle noise. This review summarizes recent progress in high-contrast imaging with particular emphasis on observational results, discoveries near and below the deuterium-burning limit, and a practical overview of large-scale surveys and dedicated instruments. I conclude with a statistical meta-analysis of deep imaging surveys in the literature. Based on observations of 384 unique and single young (≈5-300 Myr) stars spanning stellar masses between 0.1 and 3.0 M ⊙, the overall occurrence rate of 5-13 M Jup companions at orbital distances of 30-300 au is {0.6}-0.5+0.7 % assuming hot-start evolutionary models. The most massive giant planets regularly accessible to direct imaging are about as rare as hot Jupiters are around Sun-like stars. Dividing this sample into individual stellar mass bins does not reveal any statistically significant trend in planet frequency with host mass: giant planets are found around {2.8}-2.3+3.7 % of BA stars, <4.1% of FGK stars, and <3.9% of M dwarfs. Looking forward, extreme AO systems and the next generation of ground- and space-based telescopes with smaller inner working angles and deeper detection limits will increase the pace of discovery to ultimately map the demographics, composition, evolution, and origin of planets spanning a broad range of masses and ages.

  15. GIANT INTRACANALICULAR FIBROADENOMA

    PubMed Central

    Smith, Clyn; Parsons, Robert J.; Bogart, William M.

    1951-01-01

    Five cases of giant intracanalicular fibroadenoma (“cystosarcoma phylloides”) were observed at one hospital in a period of three years. In a search of the literature, additional reports of breast tumors of this kind, not included in previous reviews, were noted. As there is record of 229 cases, it would appear that this rapidly growing benign tumor should be kept in mind in the diagnosis of masses in the breast. If removal is incomplete, there may be recurrence. Simple mastectomy is the treatment of choice. Radical mastectomy should be avoided. ImagesFigure 1Figure 2.Figure 3Figure 4Figure 5 PMID:14848732

  16. Gas Giants Form Quickly

    NASA Technical Reports Server (NTRS)

    2007-01-01

    This is an artist's concept of a hypothetical 10-million-year-old star system. The bright blur at the center is a star much like our sun. The other orb in the image is a gas-giant planet like Jupiter. Wisps of white throughout the image represent traces of gas.

    Astronomers using NASA's Spitzer Space Telescope have found evidence showing that gas-giant planets either form within the first 10 million years of a sun-like star's life, or not at all. The lifespan for sun-like stars is about 10 billion years.

    The scientists came to this conclusion after searching for traces of gas around 15 different sun-like stars, most with ages ranging from 3 million to 30 million years. With the help of Spitzer's Infrared Spectrometer instrument, they were able to search for relatively warm gas in the inner regions of these star systems, an area comparable to the zone between Earth and Jupiter in our own solar system. They also used ground-based radio telescopes to search for cooler gas in the outer regions of these systems, an area comparable to the zone around Saturn and beyond.

  17. Giant solitary trichoepithelioma

    PubMed Central

    Teli, Bhavuray; Thrishuli, P. B.; Santhosh, R.; Amar, D. N.; Rajpurohit, Shravan

    2015-01-01

    Adnexal tumors like giant solitary trichoepitheliomas are uncommon to most of us to permit a ready familiarity with them. Information regarding the genesis, clinical profile, behavior, and management options for this tumor is limited. There are 18 cases reported in the world literature till date. This review attempts to provide insight to this rare tumor. Our search included indexed literature from Pubmed, Directory of Open Access Journals, Health Inter Network Access to Research Initiative and Google databases in addition to standard dermatology texts. Giant solitary trichoepithelioma is a rare trichogenic tumor with potential for local recurrence. It has predilection for the older age, but may present at any age including at birth. It has close resemblance to basal cell carcinoma and other skin adnexal tumors - clinically, cytologically, and histologically. CD10, CD 34, PHLDA1 but not p75NTR are useful adjunct markers. Surgical excision is the standard treatment. Recurrence and possible transformation into BCC cautions follow up at regular intervals. PMID:25839021

  18. Giant papillary conjunctivitis.

    PubMed Central

    Donshik, P C

    1994-01-01

    Giant papillary conjunctivitis is a syndrome found frequently as a complication of contact lenses. Many variables can affect the onset and severity of the presenting signs and symptoms. Rigid gas permeable contact lenses appear to result in less severe signs and symptoms, with a longer time before the development of giant papillary conjunctivitis. Nonionic, low-water-content soft contact lenses tend to produce less severe signs and symptoms than ionic, low-water-content soft contact lenses. Enzymatic treatment appears to lessen the severity of signs and symptoms. The association of an allergy appears to play a role in the onset of the severity of the signs and symptoms but does not appear to affect the final ability of the individual to wear contact lenses. Using multiple treatment options, such as changing the polymer to a glyceryl methyl methacrylate or a rigid lens, or utilizing a soft lens on a frequent-replacement basis, can result in a success rate of over 90%. In individuals who still have a return of symptoms, the use of topical mast cell stabilizers or a nonsteroidal anti-inflammatory drug as an adjunctive therapy offers the added possibility of keeping these patients in contact lenses. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 11 A FIGURE 11 B FIGURE 11 C FIGURE 11 D PMID:7886881

  19. Rheology of giant micelles

    NASA Astrophysics Data System (ADS)

    Cates, M. E.; Fielding, S. M.

    2006-12-01

    Giant micelles are elongated, polymer-like objects created by the self-assembly of amphiphilic molecules (such as detergents) in solution. Giant micelles are typically flexible, and can become highly entangled even at modest concentrations. The resulting viscoelastic solutions show fascinating flow behaviour (rheology) which we address theoretically in this article at two levels. First, we summarize advances in understanding linear viscoelastic spectra and steady-state nonlinear flows, based on microscopic constitutive models that combine the physics of polymer entanglement with the reversible kinetics of self-assembly. Such models were first introduced two decades ago, and since then have been shown to explain robustly several distinctive features of the rheology in the strongly entangled regime, including extreme shear thinning. We then turn to more complex rheological phenomena, particularly involving spatial heterogeneity, spontaneous oscillation, instability and chaos. Recent understanding of these complex flows is based largely on grossly simplified models which capture in outline just a few pertinent microscopic features, such as coupling between stresses and other order parameters such as concentration. The role of ‘structural memory’ (the dependence of structural parameters such as the micellar length distribution on the flow history) in explaining these highly nonlinear phenomena is addressed. Structural memory also plays an intriguing role in the little-understood shear thickening regime, which occurs in a concentration regime close to but below the onset of strong entanglement, and which is marked by a shear-induced transformation from an inviscid to a gelatinous state.

  20. Significant linkage disequilibrium between the Huntington disease gene and the loci D4S10 and D4S95 in the Dutch population

    SciTech Connect

    Skraastad, M.I.; Van de Vosse, E.; Belfroid, R.; Hoeld, K.; Vegter-van der Vlis, M.; Bakker, E.; van Ommen, G.J.B. ); Sandkuijl, L.A. )

    1992-10-01

    Significant linkage disequilibrium has been found between the Huntington disease (HD) gene and DNA markers located around D4S95 and D4S98. The linkage-disequilibrium studies favor the proximal location of the HD gene, in contrast to the conflicting results of recombination analyses. The authors have analyzed 45 Dutch HD families with 19 DNA markers and have calculated the strength of linkage disequilibrium. Highly significant linkage disequilibrium has been detected with D4S95, consistent with the studies in other populations. In contrast with most other studies, however, the area of linkage disequilibrium extends from D4S10 proximally to D4S95, covering 1,100 kb. These results confirm that the HD gene most likely maps near D4S95. 28 refs., 1 fig., 2 tabs.

  1. Allometry indicates giant eyes of giant squid are not exceptional

    PubMed Central

    2013-01-01

    Background The eyes of giant and colossal squid are among the largest eyes in the history of life. It was recently proposed that sperm whale predation is the main driver of eye size evolution in giant squid, on the basis of an optical model that suggested optimal performance in detecting large luminous visual targets such as whales in the deep sea. However, it is poorly understood how the eye size of giant and colossal squid compares to that of other aquatic organisms when scaling effects are considered. Results We performed a large-scale comparative study that included 87 squid species and 237 species of acanthomorph fish. While squid have larger eyes than most acanthomorphs, a comparison of relative eye size among squid suggests that giant and colossal squid do not have unusually large eyes. After revising constants used in a previous model we found that large eyes perform equally well in detecting point targets and large luminous targets in the deep sea. Conclusions The eyes of giant and colossal squid do not appear exceptionally large when allometric effects are considered. It is probable that the giant eyes of giant squid result from a phylogenetically conserved developmental pattern manifested in very large animals. Whatever the cause of large eyes, they appear to have several advantages for vision in the reduced light of the deep mesopelagic zone. PMID:23418818

  2. Giant magnetostrictive composites

    NASA Astrophysics Data System (ADS)

    Duenas, Terrisa Ann

    The limitation of magnetostrictive composites has been in their low magnetostrictive response when compared to their monolithic counterparts. In this dissertation research is presented describing the methods and analysis used to create a giant magnetostrictive composite (GMC) producing giant strains at low fields, exhibiting magnetization ``jumping'' and the ΔE effect. This composite combines the giant magnetostrictive material, Terfenol-D (Tb0.3Dy0.7Fe2) in particle form, with a nonmetallic binder and is capable of producing strains (at room temperature) exceeding 1000 ppm at a nominal field of 1.5 kOe mechanically unloaded and 1200 ppm at 8 MPa preload (2.5 kOe). Several studies leading to the high response of this composite are presented. A connectivity study shows that a [1-3] connected composite produces 50% more strain than a [0-3] composite. A resin study indicates that the lower the viscosity of the resin, the greater the magnetostrictive response; this is attributed to the removal of voids during degassing. A void study correlates the increase in voids to the decrease in strain response. A model is used to correlate analysis with experimental results within 10% accuracy and shows that an optimal volume fraction exists based on the properties of the binder. Using a Polyscience Spurr low- viscosity (60 cps) binder this volume fraction is nominally 20%; this optimum is attributed to the balance of epoxy contracting on the particle (built-in preload) and the actuation delivered by the magnetostrictive material. In addition to the connectivity, resin, void, and volume-fraction study, particle size and gradation studies are presented. Widely dispersed (<106, <212, <300 μm), narrowly dispersed (<45, (90-106), (275-300) μm), and an optimized bimodal (18.7% of (45-90) μm with 81.3% of (250-300) μm) particle distributions are studied. Results show that the larger the particle size, the higher the magnetostrictive response; this is attributed to the reduction of

  3. Giant vesicles: preparations and applications.

    PubMed

    Walde, Peter; Cosentino, Katia; Engel, Helen; Stano, Pasquale

    2010-05-01

    There is considerable interest in preparing cell-sized giant unilamellar vesicles from natural or nonnatural amphiphiles because a giant vesicle membrane resembles the self-closed lipid matrix of the plasma membrane of all biological cells. Currently, giant vesicles are applied to investigate certain aspects of biomembranes. Examples include lateral lipid heterogeneities, membrane budding and fission, activities of reconstituted membrane proteins, or membrane permeabilization caused by added chemical compounds. One of the challenging applications of giant vesicles include gene expressions inside the vesicles with the ultimate goal of constructing a dynamic artificial cell-like system that is endowed with all those essential features of living cells that distinguish them from the nonliving form of matter. Although this goal still seems to be far away and currently difficult to reach, it is expected that progress in this and other fields of giant vesicle research strongly depend on whether reliable methods for the reproducible preparation of giant vesicles are available. The key concepts of currently known methods for preparing giant unilamellar vesicles are summarized, and advantages and disadvantages of the main methods are compared and critically discussed. PMID:20336703

  4. [Giant adrenal myelolipoma].

    PubMed

    El Mejjad, Amine; Fekak, Hamid; Dakir, Mohamed; Sarf, Ismail; Manni, Ahmed; Meziane, Fethi

    2004-02-01

    Adrenal myelolipoma is a rare, benign, non-secreting tumour composed of adipose and haematopoietic tissue. The authors report a rare case of giant adrenal myelolipoma in a 53-year-old patient presenting with low back pain and a palpable flank mass on examination. CT scan suggested the diagnosis and surgical resection was indicated in view of the size and symptomatic nature of this mass. Histological examination confirmed the diagnosis. The outcome was favourable without recurrence after a follow-up of one year. The diagnosis of adrenal myelolipoma is based on radiology. Conservative management is generally sufficient for small asymptomatic tumours, but resection is required for large (> 5 cm) and/or symptomatic tumours.

  5. Two giant stellar complexes

    NASA Astrophysics Data System (ADS)

    Efremov, Yu. N.; Efremov, E. Yu.

    Common star complexes are huge (0.3-1 kpc in diameter) groups of relatively young stars, associations and clusters. The complexes usually form regular chains along spiral arms of grand design galaxies, being evidently formed and supported by magneto- gravitational instability developing along an arm. Special attention is given to a few large complexes which have signatures of gravitational boundness, such as round shape and high central density. Concentrations of stars and clusters in such a complex in M51 galaxy were found in this paper; we concluded it is possible to suggest that the complex is gravitationally bound. It is also stressed that some properties of the giant complex in NGC 6946 (such as its semicircular and sharp Western edge) are still enigmatic.

  6. A giant frontoethmoid mucocele with intracranial extension.

    PubMed

    Işık, Abdülcemal Ümit; Arslan, Selçuk; Arslan, Erhan; Baykal, Süleyman

    2015-02-01

    Mucoceles are mucus-containing cysts lined by epithelium. Although benign, they may show expansive growth and remain undiagnosed until symptoms due to compression of surrounding structures arise. We report a rare case of frontoethmoid mucocele with intracranial extension in an 80-year-old woman with complaints of headache, right diplopia and proptosis. A right frontoorbital craniotomy was performed, and a mucocele in the frontal sinus extending into the frontal lobe and orbit was totally removed. The patient was successfully treated without any complication. The two-year follow-up results were satisfactory. Magnetic resonance imaging excluded any recurrence of the mucocele. Combined intranasal and transcranial approach is necessary to treat giant frontoetmoid mucoceles with intracranial extension.

  7. Atmospheres of Extrasolar Giant Planets

    NASA Technical Reports Server (NTRS)

    Marley, Mark

    2006-01-01

    The next decade will almost certainly see the direct imaging of extrasolar giant planets around nearby stars. Unlike purely radial velocity detections, direct imaging will open the door to characterizing the atmosphere and interiors of extrasola planets and ultimately provide clues on their formation and evolution through time. This process has already begun for the transiting planets, placing new constraints on their atmospheric structure, composition, and evolution. Indeed the key to understanding giant planet detectability, interpreting spectra, and constraining effective temperature and hence evolution-is the atmosphere. I will review the universe of extrasolar giant planet models, focusing on what we have already learned from modeling and what we will likely be able to learn from the first generation of direct detection data. In addition to these theoretical considerations, I will review the observations and interpretation of the - transiting hot Jupiters. These objects provide a test of our ability to model exotic atmospheres and challenge our current understanding of giant planet evolution.

  8. Landscape of the lost giants

    NASA Astrophysics Data System (ADS)

    2013-09-01

    The Pleistocene megafauna extinction erased a group of remarkable animals. Whether humans had a prominent role in the extinction remains controversial, but it is emerging that the disappearance of the giants has markedly affected the environment.

  9. Pharma giants swap research programs.

    PubMed

    2014-07-01

    Pharmaceutical giants Novartis and GlaxoSmithKline (GSK) agreed in late April to swap some assets, with Novartis handing off its vaccine business to GSK and getting most of the British company's cancer portfolio in return.

  10. A Case of Giant Uterine Lipoleiomyoma Simulating Malignancy

    PubMed Central

    Karaman, Erbil; Çim, Numan; Bulut, Gülay; Elçi, Gülhan; Andıç, Esra; Tekin, Mustafa; Kolusarı, Ali

    2015-01-01

    Introduction. Uterine leiomyoma is the most common benign pathology in women and lipoleiomyoma is an extremely rare and specific type of leiomyoma. Here, we report an unusual case of giant pedunculated subserous lipoleiomyoma misdiagnosed preoperatively as leiomyosarcoma. Case. A 45-year-old woman admitted to our gynecology outpatient clinic for complaints of abdominal distention, tiredness, and pelvic pain for the last 6 months. Sonography and abdominal magnetic resonance imaging (MRI) showed a giant semisolid mass that filled whole abdominal cavity from pelvis to subdiaphragmatic area. A primary diagnosis of uterine sarcoma or ovarian malignancy was made. On operation, total abdominal hysterectomy with a pedunculated mass of size 30 × 23 × 12 cm and weighing 5.4 kg and bilateral salpingo-oophorectomy were performed. The histopathology revealed a lipoleiomyoma with extensive cystic and fatty degeneration without any malignancy. Discussion. The diagnosis of leiomyoma is done usually with pelvic ultrasound but sometimes it is difficult to reach a correct diagnosis especially in cases of giant and pedunculated lipoleiomyoma that included fatty tissue which may mimick malignancy. Conclusion. Subserous pedunculated giant lipoleiomyoma should be kept in mind in the differential diagnosis of leiomyosarcoma or ovarian malignancy. PMID:26266066

  11. Lithium-rich giants in the Galactic thick disk

    NASA Astrophysics Data System (ADS)

    Monaco, L.; Villanova, S.; Moni Bidin, C.; Carraro, G.; Geisler, D.; Bonifacio, P.; Gonzalez, O. A.; Zoccali, M.; Jilkova, L.

    2011-05-01

    Context. Lithium is a fragile element, which is easily destroyed in the stellar interior. The existence of lithium-rich giants still represents a challenge for stellar evolution models. Aims: We have collected a large database of high-resolution stellar spectra of 824 candidate thick-disk giants having 2 MASS photometry and proper motions measured by the Southern Proper-Motion Program (SPM). In order to investigate the nature of Li-rich giants, we searched this database for giants presenting a strong Li I resonance line. Methods: We performed a chemical abundance analysis on the selected stars with the MOOG code along with proper ATLAS-9 model atmospheres. The iron content and atmospheric parameters were fixed by using the equivalent width of a sample of Fe lines. We also derive abundances for C, N, and O and measure or derive lower limits on the 12C/13C isotopic ratios, which is a sensible diagnostic of the stars evolutionary status. Results: We detected five stars with a lithium abundance higher than 1.5, i.e. Li-rich according to the current definition. One of them (SPM-313132) has A(Li) > 3.3 and, because of this, belongs to the group of the rare super Li-rich giants. Its kinematics makes it a likely thin-disk member and its atmospheric parameters are compatible with it being a 4 M⊙ star either on the red giant branch (RGB) or the early asymptotic giant branch. This object is the first super Li-rich giant detected at this phase. The other four are likely low-mass thick-disk stars evolved past the RGB luminosity bump, as determined from their metallicities and atmospheric parameters. The most evolved of them lies close to the RGB-tip. It has A(Li) > 2.7 and a low 12C/13C isotopic ratio, close to the cool bottom processing predictions. Based on observations taken at the Las Campanas and La Silla/ Paranal observatory (ESO proposal ID: 077.B-0348).

  12. Resonance capture at arbitrary inclination

    NASA Astrophysics Data System (ADS)

    Namouni, F.; Morais, M. H. M.

    2015-01-01

    Resonance capture is studied numerically in the three-body problem for arbitrary inclinations. Massless particles are set to drift from outside the 1:5 resonance with a Jupiter-mass planet thereby encountering the web of the planet's diverse mean motion resonances. Randomly constructed samples explore parameter space for inclinations from 0 to 180° with 5° increments totalling nearly 6 × 105 numerical simulations. 30 resonances internal and external to the planet's location are monitored. We find that retrograde resonances are unexpectedly more efficient at capture than prograde resonances and that resonance order is not necessarily a good indicator of capture efficiency at arbitrary inclination. Capture probability drops significantly at moderate sample eccentricity for initial inclinations in the range [10°,110°]. Orbit inversion is possible for initially circular orbits with inclinations in the range [60°,130°]. Capture in the 1:1 co-orbital resonance occurs with great likelihood at large retrograde inclinations. The planet's orbital eccentricity, if larger than 0.1, reduces the capture probabilities through the action of the eccentric Kozai-Lidov mechanism. A capture asymmetry appears between inner and outer resonances as prograde orbits are preferentially trapped in inner resonances. The relative capture efficiency of retrograde resonance suggests that the dynamical lifetimes of Damocloids and Centaurs on retrograde orbits must be significantly larger than those on prograde orbits implying that the recently identified asteroids in retrograde resonance, 2006 BZ8, 2008 SO218, 2009 QY6 and 1999 LE31 may be among the oldest small bodies that wander between the outer giant planets.

  13. [Giant retroperitoneal ganglioneuroma].

    PubMed

    Sarf, Ismail; el Mejjad, Amine; Badre, Latifa; Mani, Ahmed; Aboutaieb, Rachid; Meziane, Fethi

    2003-06-01

    The authors report a new case of retroperitoneal ganglioneuroma in an 18-year-old girl presenting with abdominal mass and lumbosciatica. The diagnosis of retroperitoneal tumour was based on computed tomography and magnetic resonance imaging. Treatment consisted of complete resection of the tumour. The postoperative course was favourable with no recurrence after one year of follow-up. The authors discuss the diagnostic, therapeutic and prognostic aspects of this disease.

  14. A unique advantage for giant eyes in giant squid.

    PubMed

    Nilsson, Dan-Eric; Warrant, Eric J; Johnsen, Sönke; Hanlon, Roger; Shashar, Nadav

    2012-04-24

    Giant and colossal deep-sea squid (Architeuthis and Mesonychoteuthis) have the largest eyes in the animal kingdom [1, 2], but there is no explanation for why they would need eyes that are nearly three times the diameter of those of any other extant animal. Here we develop a theory for visual detection in pelagic habitats, which predicts that such giant eyes are unlikely to evolve for detecting mates or prey at long distance but are instead uniquely suited for detecting very large predators, such as sperm whales. We also provide photographic documentation of an eyeball of about 27 cm with a 9 cm pupil in a giant squid, and we predict that, below 600 m depth, it would allow detection of sperm whales at distances exceeding 120 m. With this long range of vision, giant squid get an early warning of approaching sperm whales. Because the sonar range of sperm whales exceeds 120 m [3-5], we hypothesize that a well-prepared and powerful evasive response to hunting sperm whales may have driven the evolution of huge dimensions in both eyes and bodies of giant and colossal squid. Our theory also provides insights into the vision of Mesozoic ichthyosaurs with unusually large eyes.

  15. Arthroscopic Decompression for a Giant Meniscal Cyst.

    PubMed

    Ohishi, Tsuyoshi; Suzuki, Daisuke; Matsuyama, Yukihiro

    2016-01-01

    The authors report the case of a giant medial meniscal cyst in an osteoarthritic knee of an 82-year-old woman that was successfully treated with only arthroscopic cyst decompression. The patient noticed a painful mass on the medial side of the right knee that had been gradually growing for 5 years. Magnetic resonance imaging showed an encapsulated large medial cystic mass measuring 80×65×40 mm that was adjacent to the medial meniscus. An accompanying horizontal tear was also detected in the middle and posterior segments of the meniscus. The medial meniscus was resected up to the capsular attachment to create bidirectional flow between the joint and the cyst with arthroscopic surgery. Magnetic resonance imaging performed 14 months postoperatively showed that the cyst had completely disappeared, and no recurrence was observed during a 2-year follow-up period. An excellent result could be obtained by performing limited meniscectomy to create a channel leading to the meniscal cyst, even though the cyst was large. Among previously reported cases of meniscal cysts, this case is the largest to be treated arthroscopically without open excision.

  16. The influence of interlayer exchange coupling in giant-magnetoresistive devices on spin diode effect in wide frequency range

    SciTech Connect

    Ziętek, Sławomir Skowroński, Witold; Wiśniowski, Piotr; Czapkiewicz, Maciej; Stobiecki, Tomasz; Ogrodnik, Piotr; Barnaś, Józef

    2015-09-21

    Spin diode effect in a giant magnetoresistive strip is measured in a broad frequency range, including resonance and off-resonance frequencies. The off-resonance dc signal is relatively strong and also significantly dependent on the exchange coupling between magnetic films through the spacer layer. The measured dc signal is described theoretically by taking into account magnetic dynamics induced by Oersted field created by an ac current flowing through the system.

  17. Giant intrapelvic solitary fibrous tumor arising from mesorectum.

    PubMed

    Soda, Hiroaki; Kainuma, Osamu; Yamamoto, Hiroshi; Nagata, Matsuo; Takiguchi, Nobuhiro; Ikeda, Atsushi; Cho, Akihiro; Gunji, Hisashi; Miyazaki, Akinari; Irei, Satoko; Araki, Akinobu

    2010-06-01

    We report a patient who had a giant pelvic solitary fibrous tumor (SFT) that was excised with the aid of aortic balloon occlusion. A 27-year-old woman was diagnosed, at another hospital, as having an inoperable intrapelvic tumor. On admission, computed tomography showed that the uterus, urinary bladder, and rectum were compressed anteriorly by a pelvic tumor with a maximum diameter of 16 cm. On magnetic resonance imaging, the tumor contained mesh-like structures showing strong intensity. Transanal needle biopsy was performed, and SFT was diagnosed by immunostaining. The tumor was supplied by feeding vessels from the inferior mesenteric artery and bilateral internal iliac arteries. Despite massive intraoperative hemorrhage, this giant tumor was excised with the help of aortic balloon occlusion. An intrapelvic SFT should be resected after careful preparation of countermeasures for hemorrhage.

  18. The presence of transfer RNA in the axoplasm of the squid giant axon.

    PubMed

    Black, M M; Lasek, R J

    1977-05-01

    Previous work has revealed that 4S RNA is the primary species of RNA in the axoplasm from the giant axons of the squid and Myxicola. This study shows that axoplasmic 4S RNA from the squid giant axon has the functional properties of tRNA. Axoplasmic RNA was charged with amino acids by aminoacyl-tRNA synthetases prepared from squid brain. Tthe aminoacylation was prevented by incubating the RNA with RNase prior to running the reaction. The amino acid-RNA complex was labile at pH 9, which is characteristic of the acyl linkage between an amino acid and its tRNA. Aminoacyl-tRNA synthetase activity was also present in the axoplasm, primarily in the soluble fraction.

  19. Formation of giant planets

    NASA Astrophysics Data System (ADS)

    Magni, G.; Coradini, A.

    2003-04-01

    In this presentation we address the problem of the formation of giant planets and their regular satellites. We study in particular the problem of formation of the Jupiter System comparing the results of the model with the present characteristics of the system, in order to identify what are those better represented by our approach. In fact here, using a 3-D hydro-dynamical code, we study the modalities of gas accretion onto a solid core, believed to be the seed from which Jupiter started. To do that we have modelled three main regions: the central planet, a turbulent accretion disk surrounding it and an extended region from which the gas is collected. In the extended region we treat the gas as a frictionless fluid. Our main goal is to identify what are the characteristics of the planet during its growth and the physical parameters affecting its growth at the expenses of the nebular gas present in the feeding zone. Moreover we want to understand what are the thermodynamical parameters characterizing the gas captured by the planet and swirling around it. Finally, we check if a disk can be formed in prograde rotation around the planet and if this disk can survive the final phases of the planet formation. Due to the interaction between the accreting planet and the disk it has been necessary to develop a complete model of the Jupiter’s structure. In fact the radiation emitted by the growing planet heats up the surrounding gas. In turn the planet’s thermodynamic structure depend on the mass accretion rate onto it. When the accretion is rapid, shock waves in the gas are formed close to the planet. This region cannot be safely treated by a numerical code; for this reason we have developed a semi-analytically model of a a turbulent accretion disk to be considered as transition between the planet and the surrounding disk.

  20. Giant Magellan Telescope: overview

    NASA Astrophysics Data System (ADS)

    Johns, Matt; McCarthy, Patrick; Raybould, Keith; Bouchez, Antonin; Farahani, Arash; Filgueira, Jose; Jacoby, George; Shectman, Steve; Sheehan, Michael

    2012-09-01

    The Giant Magellan Telescope (GMT) is a 25-meter optical/infrared extremely large telescope that is being built by an international consortium of universities and research institutions. It will be located at the Las Campanas Observatory, Chile. The GMT primary mirror consists of seven 8.4-m borosilicate honeycomb mirror segments made at the Steward Observatory Mirror Lab (SOML). Six identical off-axis segments and one on-axis segment are arranged on a single nearly-paraboloidal parent surface having an overall focal ratio of f/0.7. The fabrication, testing and verification procedures required to produce the closely-matched off-axis mirror segments were developed during the production of the first mirror. Production of the second and third off-axis segments is underway. GMT incorporates a seven-segment Gregorian adaptive secondary to implement three modes of adaptive-optics operation: natural-guide star AO, laser-tomography AO, and ground-layer AO. A wide-field corrector/ADC is available for use in seeing-limited mode over a 20-arcmin diameter field of view. Up to seven instruments can be mounted simultaneously on the telescope in a large Gregorian Instrument Rotator. Conceptual design studies were completed for six AO and seeing-limited instruments, plus a multi-object fiber feed, and a roadmap for phased deployment of the GMT instrument suite is being developed. The partner institutions have made firm commitments for approximately 45% of the funds required to build the telescope. Project Office efforts are currently focused on advancing the telescope and enclosure design in preparation for subsystem- and system-level preliminary design reviews which are scheduled to be completed in the first half of 2013.

  1. Rotation of Giant Stars

    NASA Astrophysics Data System (ADS)

    Kissin, Yevgeni; Thompson, Christopher

    2015-07-01

    The internal rotation of post-main sequence stars is investigated, in response to the convective pumping of angular momentum toward the stellar core, combined with a tight magnetic coupling between core and envelope. The spin evolution is calculated using model stars of initial mass 1, 1.5, and 5 {M}ȯ , taking into account mass loss on the giant branches. We also include the deposition of orbital angular momentum from a sub-stellar companion, as influenced by tidal drag along with the excitation of orbital eccentricity by a fluctuating gravitational quadrupole moment. A range of angular velocity profiles {{Ω }}(r) is considered in the envelope, extending from solid rotation to constant specific angular momentum. We focus on the backreaction of the Coriolis force, and the threshold for dynamo action in the inner envelope. Quantitative agreement with measurements of core rotation in subgiants and post-He core flash stars by Kepler is obtained with a two-layer angular velocity profile: uniform specific angular momentum where the Coriolis parameter {Co}\\equiv {{Ω }}{τ }{con}≲ 1 (here {τ }{con} is the convective time), and {{Ω }}(r)\\propto {r}-1 where {Co}≳ 1. The inner profile is interpreted in terms of a balance between the Coriolis force and angular pressure gradients driven by radially extended convective plumes. Inward angular momentum pumping reduces the surface rotation of subgiants, and the need for a rejuvenated magnetic wind torque. The co-evolution of internal magnetic fields and rotation is considered in Kissin & Thompson, along with the breaking of the rotational coupling between core and envelope due to heavy mass loss.

  2. Experimental and Theoretical Studies of Pressure Broadened Alkali-Metal Atom Resonance Lines

    NASA Technical Reports Server (NTRS)

    Shindo, F.; Zhu, C.; Kirby, K.; Babb, J. F.

    2006-01-01

    We are carrying out a joint theoretical and experimental research program to study the broadening of alkali atom resonance lines due to collisions with helium and molecular hydrogen for applications to spectroscopic studies of brown dwarfs and extrasolar giant planets.

  3. Arabidopsis thaliana Nfu2 accommodates [2Fe-2S] or [4Fe-4S] clusters and is competent for in vitro maturation of chloroplast [2Fe-2S] and [4Fe-4S] cluster-containing proteins†

    PubMed Central

    Gao, Huanyao; Subramanian, Sowmya; Couturier, Jérémy; Naik, Sunil; Kim, Sung-Kun; Leustek, Thomas; Knaff, David B.; Wu, Hui-Chen; Vignols, Florence; Huynh, Boi Hanh; Rouhier, Nicolas; Johnson, Michael K.

    2013-01-01

    Nfu-type proteins are essential in the biogenesis of iron-sulfur (Fe-S) clusters in numerous organisms. A number of phenotypes including low levels of Fe-S cluster incorporation are associated with deletion of the gene encoding a chloroplast-specific Nfu-type protein, Nfu2 from Arabidopsis thaliana (AtNfu2). Here we report that recombinant AtNfu2 is able to assemble both [2Fe-2S] and [4Fe-4S] clusters. Analytical data and gel filtration studies support cluster/protein stoichiometries of one [2Fe-2S] cluster/homotetramer and one [4Fe-4S] cluster/homodimer. The combination of UV-visible absorption and circular dichroism, resonance Raman and Mössbauer spectroscopies has been employed to investigate the nature, properties and transfer of the clusters assembled on Nfu2. The results are consistent with subunit-bridging [2Fe-2S]2+ and [4Fe-4S]2+ clusters coordinated by the cysteines in the conserved CXXC motif. The results also provided insight into the specificity of Nfu2 for maturation of chloroplastic Fe-S proteins via intact, rapid and quantitative cluster transfer. [2Fe-2S] cluster-bound Nfu2 is shown to be an effective [2Fe-2S]2+ cluster donor for glutaredoxin S16, but not glutaredoxin S14. Moreover, [4Fe-4S] cluster-bound Nfu2 is shown to be a very rapid and efficient [4Fe-4S]2+ cluster donor for adenosine 5′-phosphosulfate reductase (APR1) and yeast two-hybrid studies indicate that APR1 forms a complex with Nfu2, but not with Nfu1 and Nfu3, the two other chloroplastic Nfu proteins. This cluster transfer is likely to be physiologically relevant and is particularly significant for plant metabolism as APR1 catalyzes the second step in reductive sulfur assimilation which ultimately results in the biosynthesis of cysteine, methionine, glutathione, and Fe-S clusters. PMID:24032747

  4. Giant serpentine aneurysm arising from the middle cerebral artery successfully treated with trapping and anastomosis: case report.

    PubMed

    Abiko, Masaru; Ikawa, Fusao; Ohbayashi, Naohiko; Mitsuhara, Takafumi; Nosaka, Ryo; Inagawa, Tetsuji

    2009-02-01

    A 56-year-old man presented with a giant serpentine aneurysm arising from the middle cerebral artery (MCA) manifesting as right hemiparesis and motor aphasia. Magnetic resonance imaging and digital subtraction angiography identified the giant serpentine aneurysm arising from the MCA. The patient was treated surgically. Temporary clipping of the distal channel induced thrombosis in the vascular channel, and the thrombosis was aspirated with an ultrasonic suction device after superficial temporal artery-MCA anastomosis. This case shows that initial occlusion of the distal channel is effective to treat giant serpentine aneurysm. PMID:19246869

  5. Meibomian gland function and giant papillary conjunctivitis.

    PubMed

    Mathers, W D; Billborough, M

    1992-08-15

    We examined 42 contact lens-wearing patients for clinical evidence of giant papillary conjunctivitis and for meibomian gland dysfunction with gland dropout. Fifteen patients were free of clinical signs and symptoms of giant papillary conjunctivitis, whereas 27 had clinical symptoms and evidence of giant papillary conjunctivitis. Patients with giant papillary conjunctivitis had significantly more gland dropout with an average of 0.6 +/- 1.2 gland absent in both lower eyelids compared with 0.2 +/- 0.4 gland absent in patients without giant papillary conjunctivitis. Additionally, the viscosity of meibomian gland excreta was greater in the giant papillary conjunctivitis group. There was no difference in tear osmolarity or in the Schirmer test results between the two groups. These results indicated patients with giant papillary conjunctivitis were more likely to have meibomian gland dysfunction with gland dropout than patients without giant papillary conjunctivitis.

  6. Structure and Function of Four Classes of the 4Fe-4S Protein, IspH.

    PubMed

    Rao, Guodong; Oldfield, Eric

    2016-07-26

    IspH, (E)-1-hydroxy-2-methyl-but-2-enyl 4-diphosphate reductase, is an essential enzyme in isoprenoid biosynthesis and an important drug/herbicide target. Using X-ray crystallographic, bioinformatics, mutagenesis/kinetics/stability, and electron paramagnetic resonance (EPR) results, we show that organisms from different environments ultilize one of four main IspH classes. The classes are based on the arrangement of the aromatic residues near the 4Fe-4S cluster and the presence or absence of N- and C-terminal extensions. Class A enzymes are found primarily in anaerobic and microaerophilic bacteria. Class B enzymes are found in aerobic bacteria. Class C enzymes are found in cyanobacteria and plants. Class D enzymes are found in apicomplexan parasites. Using mutagenesis, we show that the cluster-associated aromatic groups in class A and class B IspHs enhance cluster oxidative stability. Y198A, F302A, and a C-terminal truncation mutant of the class B (Escherichia coli) IspH have catalytic activity lower than that of the wild-type protein when using methyl viologen as the electron donor, but higher activity with dithionite as the electron donor, due to ready access of the small reductant to the cluster, consistent with their increased oxygen and H2O2 sensitivity. F302A has the largest effect on the reaction rates, and EPR studies indicate this residue affects Fe-S cluster structure. Similar effects on cluster stability are seen with class A (F14A and Y98A) mutants; however, effects on ET rates are smaller, and there are no differences between the EPR spectra of mutant and wild-type proteins. Overall, the results are of general interest because they show, for the first time, that there are multiple IspH classes that have evolved to allow organisms to survive in diverse oxidative-stress environments. PMID:27357244

  7. Sizing Up Red-Giant Twins

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-02-01

    In KIC 9246715, two red-giant stars twins in nearly every way circle each other in a 171-day orbit. This binary pair may be a key to learning about masses and radii of stars with asteroseismology, the study of oscillations in the interiors of stars.Two Ways to MeasureIn order to understand a stars evolution, it is critical that we know its mass and radius. Unfortunately, these quantities are often difficult to pin down!One of the few cases in which we can directly measure stars masses and radii is in eclipsing binaries, wherein two stars eclipse each other as they orbit. If we have a well-sampled light curve for the binary, as well as radial velocities for both stars, then we can determine the stars complete orbital information, including their masses and radii.But there may be another way to obtain stellar mass and radius: asteroseismology. In asteroseismology, oscillations inside stars are used to characterize the stellar interiors. Conveniently, if a star with a convective envelope exhibits solar-like oscillations, these oscillations can be directly compared to those of the Sun. Mass and radius scaling relations which use the Sun as a benchmark and scale based on the stars temperature can then be used to derive the mass and radius of the star.Test Subjects from KeplerSolar-like oscillations from KIC 9246715 are shown in red across different resonant frequencies. The oscillations of a single red-giant star with similar properties are shown upside down in grey for reference. [Rawls et al. 2016]Of course, scaling relations are only useful if we can test them! A team of scientists including Meredith Rawls (New Mexico State University) has identified 18 red-giant eclipsing binaries in the Kepler field of view that also exhibit solar-like oscillations perfect for testing the scaling relations.In a recent study led by Rawls, the team analyzed the first of these binaries, KIC 9246715. Using the Kepler light curves in addition to radial velocity measurements from high

  8. Giant myoma and erythrocytosis syndrome.

    PubMed

    Ozsaran, A A; Itil, I M; Terek, C; Kazandi, M; Dikmen, Y

    1999-08-01

    The objective of this study is to discuss the myomatous erythrocytosis syndrome in a patient with a giant subserous uterine myoma. She presented with plethora and an abdominal mass. After venesection of 4 units of blood, the preoperative haematocrit value of 53.3% and haemoglobin value of 17.5 g/dL had decreased to 48.6% and 16.8 g/dL levels, respectively. After the operative extraction of the giant subserous myoma with attached uterus weighing 14.2 kg, the haematocrit and the haemoglobin values had regressed to 40.3% and 14.3 g/dL levels, respectively. The findings indicated that the giant subserous myoma was the cause of the myomatous erythrocytosis syndrome in this patient. PMID:10554963

  9. Structure of giant muscle proteins

    PubMed Central

    Meyer, Logan C.; Wright, Nathan T.

    2013-01-01

    Giant muscle proteins (e.g., titin, nebulin, and obscurin) play a seminal role in muscle elasticity, stretch response, and sarcomeric organization. Each giant protein consists of multiple tandem structural domains, usually arranged in a modular fashion spanning 500 kDa to 4 MDa. Although many of the domains are similar in structure, subtle differences create a unique function of each domain. Recent high and low resolution structural and dynamic studies now suggest more nuanced overall protein structures than previously realized. These findings show that atomic structure, interactions between tandem domains, and intrasarcomeric environment all influence the shape, motion, and therefore function of giant proteins. In this article we will review the current understanding of titin, obscurin, and nebulin structure, from the atomic level through the molecular level. PMID:24376425

  10. Review of Giant cell arteritis

    PubMed Central

    Chacko, Joseph G.; Chacko, J. Anthony; Salter, Michael W.

    2014-01-01

    Giant-cell arteritis (GCA) is a systemic autoimmune disease affecting primarily the elderly. Giant cell arteritis can cause sudden and potentially bilateral sequential vision loss in the elderly. Therefore, it is considered a medical emergency in ophthalmology and a significant cause of morbidity in an increasingly aging population. Ophthalmologists need to be able to recognize the classic symptoms and signs of this disease, and then be able to work-up and treat these patients in an efficient manner. An in-depth review of GCA from the literature as well as personal clinical experience follows. PMID:25859139

  11. Chemical Abundances of Symbiotic Giants

    NASA Astrophysics Data System (ADS)

    Gałan, C.; Mikołajewska, J.; Hinkle, K. H.; Joyce, R. R.

    2015-12-01

    High resolution (R ˜ 50000), near-IR spectra were used to measure photospheric abundances of CNO and elements around the iron peak for 24 symbiotic giants. Spectrum synthesis was employed using local thermal equilibrium and hydrostatic model atmospheres. The metallicities are distributed in a wide range with maximum around [Fe/H] ˜-0.4 - - 0.3 dex. Enrichment in 14N indicates that all the sample giants have experienced the first dredge-up. The relative abundance of [Ti/Fe] is generally large in red symbiotic systems.

  12. Charting the Giants

    NASA Astrophysics Data System (ADS)

    2004-06-01

    zero expansion asymptotically after an infinite time and has a flat geometry). All three observational tests by means of supernovae (green), the cosmic microwave background (blue) and galaxy clusters converge at a Universe around Ωm ~ 0.3 and ΩΛ ~ 0.7. The dark red region for the galaxy cluster determination corresponds to 95% certainty (2-sigma statistical deviation) when assuming good knowledge of all other cosmological parameters, and the light red region assumes a minimum knowledge. For the supernovae and WMAP results, the inner and outer regions corespond to 68% (1-sigma) and 95% certainty, respectively. References: Schuecker et al. 2003, A&A, 398, 867 (REFLEX); Tonry et al. 2003, ApJ, 594, 1 (supernovae); Riess et al. 2004, ApJ, 607, 665 (supernovae) Galaxy clusters are far from being evenly distributed in the Universe. Instead, they tend to conglomerate into even larger structures, "super-clusters". Thus, from stars which gather in galaxies, galaxies which congregate in clusters and clusters tying together in super-clusters, the Universe shows structuring on all scales, from the smallest to the largest ones. This is a relict of the very early (formation) epoch of the Universe, the so-called "inflationary" period. At that time, only a minuscule fraction of one second after the Big Bang, the tiny density fluctuations were amplified and over the eons, they gave birth to the much larger structures. Because of the link between the first fluctuations and the giant structures now observed, the unique REFLEX catalogue - the largest of its kind - allows astronomers to put considerable constraints on the content of the Universe, and in particular on the amount of dark matter that is believed to pervade it. Rather interestingly, these constraints are totally independent from all other methods so far used to assert the existence of dark matter, such as the study of very distant supernovae (see e.g. ESO PR 21/98) or the analysis of the Cosmic Microwave background (e

  13. Formation of (4R)- and (4S)-4-hydroxyochratoxin A from ochratoxin A by liver microsomes from various species.

    PubMed Central

    Størmer, F C; Hansen, C E; Pedersen, J I; Hvistendahl, G; Aasen, A J

    1981-01-01

    Two metabolic products were formed from ochratoxin A by human, pig, and rat liver microsomal fractions in the presence of reduced nicotinamide adenine dinucleotide phosphate. They were isolated from the incubation mixture in the presence of pig liver microsomes by extraction, thin-layer chromatography, and high-pressure liquid chromatography Their structures are suggested to be (4R)- and (4S)-4-hydroxyochratoxin A on the basis of mass and nuclear magnetic resonance spectroscopy. Km and the maximum velocity for the formation of the two metabolites by human, pig, and rat microsomes were determined. Their formation was inhibited by carbon monoxide and metyrapone. The results indicate that the microsomal hydroxylation system is a cytochrome P-450 and that different species are involved in the formation of the two epimeric forms of 4-hydroxyochratoxin A. PMID:7316512

  14. Role of the [Fe4S4] cluster in mediating disulfide reduction in spinach ferredoxin:thioredoxin reductase.

    PubMed

    Staples, C R; Gaymard, E; Stritt-Etter, A L; Telser, J; Hoffman, B M; Schürmann, P; Knaff, D B; Johnson, M K

    1998-03-31

    Thioredoxin reduction in plant chloroplasts is catalyzed by a unique class of disulfide reductases which use a one-electron donor, [Fe2S2]2+,+ ferredoxin, and has an active site involving a disulfide in close proximity to a [Fe4S4]2+ cluster. In this study, spinach ferredoxin:thioredoxin reductase (FTR) reduced with stoichiometric amounts of reduced benzyl viologen or frozen under turnover conditions in the presence of thioredoxin is shown to exhibit a slowly relaxing S = 1/2 resonance (g = 2.11, 2.00, 1.98) identical to that of a modified form of the enzyme in which one of the cysteines of the active-site disulfide is alkylated with N-ethylmaleimide (NEM-FTR). Hence, in accord with the previous proposal [Staples, C.R., Ameyibor, E., Fu, W., Gardet-Salvi, L., Stritt-Etter, A.-L., Schürmann, P., Knaff, D.B., and Johnson, M.K. (1996) Biochemistry 35, 11425-11434], NEM-FTR is shown to be a stable analogue of a one-electron-reduced enzymatic intermediate. The properties of the Fe-S cluster in NEM-FTR have been further investigated by resonance Raman and electron nuclear double resonance spectroscopies; the results, taken together with the previous UV-visible absorption, variable temperature magnetic circular dichroism, and resonance Raman data, indicate the presence of a novel type of [Fe4S4]3+ cluster that is coordinated by five cysteinates with little unpaired spin density delocalized onto the cluster-associated cysteine of the active-site disulfide. While the ligation site of the fifth cysteine remains undefined, the best candidate is a cluster bridging sulfide. On the basis of the spectroscopic and redox results, mechanistic schemes are proposed for the benzyl viologen-mediated two-electron-reduction of FTR and the catalytic mechanism of FTR. The catalytic mechanism involves novel S-based cluster chemistry to facilitate electron transfer to the active-site disulfide resulting in covalent attachment of the electron-transfer cysteine and generation of the free

  15. Giant intradural extramedullary spinal hydatid cyst--a rare presentation.

    PubMed

    Rashid, Muddassir; Kirmani, Sanna; Rashid, Mubashir

    2012-01-01

    The hydatidosis, or echinococcosis, has a characteristic geographic distribution, occurring most frequently in sheep-raising regions in Mediterranean, Central Asian, and South American countries and in Australia. Spinal hydatidosis is very rare, and intradural location is a rarer category of spinal hydatidosis. We report a case of intradural extramedullary spinal hydatid cyst in a 9-year-old boy. On magnetic resonance imaging, an intradural extramedullary giant cystic lesion was seen mimicking an arachnoid cyst. However, endemic origin of the patient and positive serology helped to make the diagnosis of hydatid cyst, which was confirmed on postoperative histopathology.

  16. On the Nature and Timing of Giant Planet Migration in the Solar System

    NASA Astrophysics Data System (ADS)

    Agnor, Craig B.

    2016-05-01

    Giant planet migration is a natural outcome of gravitational scattering and planet formation processes (Fernandez & Ip 1984). There is compelling evidence that the solar system's giant planets experienced large-scale migration involving close approaches between planets as well as smooth radial migration via planetesimal scattering. Aspects of giant planet migration have been invoked to explain many features of the outer solar system including the resonant structure of the Kuiper Belt (e.g., Malhotra 1993, Levison et al. 2008), the eccentricities of Jupiter and Saturn (Tsiganis et al. 2005, Morbidelli et al. 2009), the capture of Jupiter's Trojan companions (Morbidelli et al. 2005) and the capture of irregular planetary satellites (e.g., Nesvorny et al. 2007) to name a few. If this migration epoch occurred after the formation of the inner planets, then it may also explain the so-called lunar Late Heavy Bombardment (Gomes et al. 2005). This scenario necessarily requires coeval terrestrial and migrating giant planets. Recent N-body integrations exploring this issue have shown that giant planet migration may excite the terrestrial system via nodal and apsidal secular resonances (e.g., Brasser et al. 2013), may drive the terrestrial planets to crossing orbits (Kaib & Chambers 2016) or alternatively leave the inner solar system in a state closely resembling the observed one (Roig et al. 2016). The factors accounting for the large range of outcomes remain unclear. Using linear secular models and N-body simulations I am identifying and characterising the principal aspects of giant planet migration that excite the terrestrial planets' orbits. I will present these results and discuss how they inform the nature and timing of giant planet migration in the solar system.

  17. Optically Pumped Lasing of Ar(4p -->4s) Excited in Linear Microplasma Arrays at Atmospheric Pressure

    NASA Astrophysics Data System (ADS)

    Rawlins, Wilson; Galbally-Kinney, Kristin; Davis, Steven; Hoskinson, Alan; Hopwood, Jeffrey

    2014-10-01

    The optically pumped rare-gas metastable laser is a chemically inert analogue to alkali laser systems. These devices require efficient generation of electronically excited metastable atoms in a continuous-wave electric discharge in flowing gas mixtures at elevated pressure. Linear arrays of microstrip resonators are well suited for this task. We have observed CW optical gain and lasing at 912 nm using linear micro-discharge arrays to generate metastable rare-gas atoms at atmospheric pressure. Ar(4s) metastables are generated in flowing Ar/He mixtures by low-power, CW linear array microplasmas operating near 900 MHz and 1 atm. The metastables are optically excited to selected states in the Ar(4p) manifold by a tunable, CW Ti:S laser. Collisional energy transfer within the manifold produces a population inversion. The Ar(4s) concentration and the optical gain are probed by tunable diode laser spectroscopy. Supported by the Air Force Research Laboratory and High Energy Laser Joint Technology Office.

  18. Giant Dipole Resonance decay of hot rotating 88Mo

    NASA Astrophysics Data System (ADS)

    Ciemała, M.; Kmiecik, M.; Maj, A.; Kravchuk, V. L.; Gramegna, F.; Barlini, S.; Casini, G.; Camera, F.

    2014-03-01

    An experiment focusing on study of the properties of hot rotating compound nucleus of 88Mo was performed in LNL Legnaro using 48Ti beam at energies of 300 and 600 MeV on 40Ca target. The compound nucleus was produced at the temperatures of 3 and 4.5 MeV, with angular momentum distribution with lmax > 60 ħ (i.e. exceeding the crtical angular momentum for fission). High-energy gamma rays, measured in coincidence with evaporation residues and alpha particles, were analyzed with the statistical model. The GDR parameters were obtained from the best fit to the data, which allowed investigating an evolution of the GDR width up to high temperatures.

  19. Relativistic effective interaction for nuclei, giant resonances, and neutron stars

    SciTech Connect

    Fattoyev, F. J.; Piekarewicz, J.; Horowitz, C. J.; Shen, G.

    2010-11-15

    Nuclear effective interactions are useful tools in astrophysical applications especially if one can guide the extrapolations to the extremes regions of isospin and density that are required to simulate dense, neutron-rich systems. Isospin extrapolations may be constrained in the laboratory by measuring the neutron skin thickness of a heavy nucleus, such as {sup 208}Pb. Similarly, future observations of massive neutron stars will constrain the extrapolations to the high-density domain. In this contribution we introduce a new relativistic effective interaction that is simultaneously constrained by the properties of finite nuclei, their collective excitations, and neutron-star properties. By adjusting two of the empirical parameters of the theory, one can efficiently tune the neutron skin thickness of {sup 208}Pb and the maximum neutron-star mass. We illustrate this procedure in response to the recent interpretation of x-ray observations by Steiner, Lattimer, and Brown that suggests that the FSUGold effective interaction predicts neutron-star radii that are too large and a maximum stellar mass that is too small. The new effective interaction is fitted to a neutron skin thickness in {sup 208}Pb of only R{sub n}-R{sub p}=0.16 fm and yields a moderately large maximum neutron-star mass of 1.94 M{sub {center_dot}}.

  20. The giant panda gut microbiome.

    PubMed

    Wei, Fuwen; Wang, Xiao; Wu, Qi

    2015-08-01

    Giant pandas (Ailuropoda melanoleuca) are bamboo specialists that evolved from carnivores. Their gut microbiota probably aids in the digestion of cellulose and this is considered an example of gut microbiota adaptation to a bamboo diet. However, this issue remains unresolved and further functional and compositional studies are needed.

  1. Giant Serpentine Aneurysms: Multidisciplinary Management

    PubMed Central

    Anshun, W.; Feng, L.; Daming, W.

    2000-01-01

    Summary Sixty-five cases of intracranial giant serpentine aneurysms (GSΛs), including 61 cases reported in the literature and four additional cases presented in this study were reviewed. The clinical presentation, possible causes, natural history, and especially management of GSAs are discussed with emphasis on the need for aggressive intervention and multidisciplinary management. PMID:20667180

  2. The giant panda gut microbiome.

    PubMed

    Wei, Fuwen; Wang, Xiao; Wu, Qi

    2015-08-01

    Giant pandas (Ailuropoda melanoleuca) are bamboo specialists that evolved from carnivores. Their gut microbiota probably aids in the digestion of cellulose and this is considered an example of gut microbiota adaptation to a bamboo diet. However, this issue remains unresolved and further functional and compositional studies are needed. PMID:26143242

  3. There might be giants: unseen Jupiter-mass planets as sculptors of tightly packed planetary systems

    NASA Astrophysics Data System (ADS)

    Hands, T. O.; Alexander, R. D.

    2016-03-01

    The limited completeness of the Kepler sample for planets with orbital periods ≳1 yr leaves open the possibility that exoplanetary systems may host undetected giant planets. Should such planets exist, their dynamical interactions with the inner planets may prove vital in sculpting the final orbital configurations of these systems. Using an N-body code with additional forces to emulate the effects of a protoplanetary disc, we perform simulations of the assembly of compact systems of super-Earth-mass planets with unseen giant companions. The simulated systems are analogous to Kepler-11 or Kepler-32 in that they contain four or five inner super-Earths, but our systems also contain longer-period giant companions which are unlikely to have been detected by Kepler. We find that giant companions tend to break widely spaced first-order mean-motion resonances, allowing the inner planets to migrate into tighter resonances. This leads to more compact architectures and increases the occurrence rate of Laplace resonant chains.

  4. A giant subserosal uterine leiomyoma mimicking an abdominal mass: multimodal imaging data.

    PubMed

    Kalayci, Tugce Ozlem; Akatlı, Ayşe Nur; Sönmezgöz, Fitnet; Türkmen Şamdancı, Emine

    2015-01-01

    Giant uterine leiomyomas are extremely rare neoplasms and are challenging both diagnostically and therapeutically. A 49-year-old premenopausal female presented at our Department complaining of abdominal pain and distention for several years. Ultrasound (US), color Doppler US, abdominal computed tomography imaging after administration of contrast material, and abdominal magnetic resonance imaging were performed. Histopathologic examination revealed a pedunculated subserosal uterine leiomyoma. In this case report, we present abdominopelvic multimodal radiologic imaging findings of our patient with a giant subserosal uterine leiomyoma, in conjunction with histopathological findings.

  5. Giant Cell Reparative Granuloma of the Petrous Temporal Bone

    PubMed Central

    Williams, Joy C.; Thorell, William E.; Treves, John S.; Fidler, Mary E.; Moore, Gary F.; Leibrock, Lyal G.

    2000-01-01

    Giant cell reparative granuloma (GCRG) is an unusual, benign bone lesion that most commonly affects the maxilla and mandible; skull involvement is rare. The etiology is uncertain but may be related to trauma. GCRG is difficult to distinguish from giant cell tumor of the bone and has a lower recurrence rate. Thirteen reports of temporal bone GCRG in 11 patients have been reported. One report of a petrous GCRG in a 3-year-old girl has been identified. A 38-year-old male presented with a 2-year history of fullness in his left ear, ipsilateral hearing loss, and intermittent cacosmia. Computed tomography and magnetic resonance imaging revealed a large left-sided anterior temporal extradural mass. The patient underwent a left frontotemporal craniotomy and resection of a left temporal fossa tumor that involved the petrous and squamous parts of the temporal bone. The patient's post-operative course was uneventful, except for increased hearing loss secondary to opening of the epitympanum. Follow-up at one month revealed no other problems. Histopathology of the specimen was consistent with a giant cell reparative granuloma. ImagesFigure 1Figure 2p91-aFigure 3 PMID:17171108

  6. Photoionization studies of the 2p resonances of atomic calcium

    NASA Astrophysics Data System (ADS)

    Obst, B.; Hansen, J. E.; Sonntag, B.; Wernet, Ph.; Zimmermann, P.

    2002-06-01

    The Ca 2p resonances at 345-355 eV were studied by photoion and photoelectron spectroscopy using monochromatized synchrotron radiation and atomic-beam technique. The analysis of the excitation and decay of these resonances shows strong configuration mixing between the different subshells of the valence electrons 4s, 3d, and 4p. In the case of the 2p-13/2 resonance structure at 348 eV there are two excited states with nearly equal contributions from the configuration 2p53d4s2 and 2p53d24s, which gives rise to strong variations of the resonantly enhanced 3p4(3d,4s)3 photoelectron lines when scanning the photon energy across the resonance.

  7. Giant Raman gain in silicon nanocrystals

    PubMed Central

    Sirleto, Luigi; Antonietta Ferrara, Maria; Nikitin, Timur; Novikov, Sergei; Khriachtchev, Leonid

    2012-01-01

    Nanostructured silicon has generated a lot of interest in the past decades as a key material for silicon-based photonics. The low absorption coefficient makes silicon nanocrystals attractive as an active medium in waveguide structures, and their third-order nonlinear optical properties are crucial for the development of next generation nonlinear photonic devices. Here we report the first observation of stimulated Raman scattering in silicon nanocrystals embedded in a silica matrix under non-resonant excitation at infrared wavelengths (~1.5 μm). Raman gain is directly measured as a function of the silicon content. A giant Raman gain from the silicon nanocrystals is obtained that is up to four orders of magnitude greater than in crystalline silicon. These results demonstrate the first Raman amplifier based on silicon nanocrystals in a silica matrix, thus opening new perspectives for the realization of more efficient Raman lasers with ultra-small sizes, which would increase the synergy between electronic and photonic devices. PMID:23187620

  8. Wandering Gas Giants and Lunar Bombardment

    NASA Astrophysics Data System (ADS)

    Taylor, G. J.

    2006-08-01

    There may have been a dramatic event early in the history of the Solar System--the intense bombardment of the inner planets and the Moon by planetesimals during a narrow interval between 3.92 and 3.85 billion years ago, called the late heavy bombardment, but also nicknamed the lunar cataclysm. The evidence for this event comes from Apollo lunar samples and lunar meteorites. While not proven, it makes for an interesting working hypothesis. If correct, what caused it to happen? A group of physicists from the Observatoire de la Côte d'Azur (Nice, France), GEA/OV/Universidade Federal do Rio de Janeiro and Observatorio Nacional/MTC (Rio de Janeiro, Brazil), and the Southwest Research Institute (Boulder, Colorado) conducted a series of studies of the dynamics of the early Solar System. Alessandro Morbidelli, Kleomenis Tsiganis, Rodney Gomes, and Harold Levison simulated the migration of Saturn and Jupiter. When the orbits of these giant planets reached the special condition of Saturn making one trip around the Sun for every two trips by Jupiter (called the 1:2 resonance), violent gravitational shoves made the orbits of Neptune and Uranus unstable, causing them to migrate rapidly and scatter countless planetesimals throughout the Solar System. This dramatic event could have happened in a short interval, anywhere from 200 million years to a billion years after planet formation, causing the lunar cataclysm, which would have affected all the inner planets.

  9. Tides in Giant Planets

    NASA Astrophysics Data System (ADS)

    Stevenson, David J.

    2015-11-01

    possibility that the tidal frequency is coincidentally close to some resonance, as would be required if (as some have suggested) the tidal Q is currently small (e.g., a few thousand or less). Predictions and detectability for Juno will be presented.

  10. Asteroseismology of Red Giant stars

    NASA Astrophysics Data System (ADS)

    Tarrant, N. J.; Chaplin, W. J.; Elsworth, Y. P.; Spreckley, S. A.; Stevens, I. R.

    2008-12-01

    Sun-like oscillations, that is p-modes excited stochastically by convective noise, have now been observed in a number of Red Giant stars. Compared to those seen in the Sun, these modes are of large amplitude and long period, making the oscillations attractive prospects for observation. However, the low Q-factor of these modes, and issues relating to the rising background at low frequencies, present some interesting challenges for identifying modes and determining the related asteroseismic parameters. We report on the analysis procedure adopted for peak-bagging by our group at Birming- ham, and the techniques used to robustly ensure these are not a product of noise. I also show results from a number of giants extracted from multi-year observations with the SMEI instrument

  11. Proteorhodopsin genes in giant viruses.

    PubMed

    Yutin, Natalya; Koonin, Eugene V

    2012-01-01

    Viruses with large genomes encode numerous proteins that do not directly participate in virus biogenesis but rather modify key functional systems of infected cells. We report that a distinct group of giant viruses infecting unicellular eukaryotes that includes Organic Lake Phycodnaviruses and Phaeocystis globosa virus encode predicted proteorhodopsins that have not been previously detected in viruses. Search of metagenomic sequence data shows that putative viral proteorhodopsins are extremely abundant in marine environments. Phylogenetic analysis suggests that giant viruses acquired proteorhodopsins via horizontal gene transfer from proteorhodopsin-encoding protists although the actual donor(s) could not be presently identified. The pattern of conservation of the predicted functionally important amino acid residues suggests that viral proteorhodopsin homologs function as sensory rhodopsins. We hypothesize that viral rhodopsins modulate light-dependent signaling, in particular phototaxis, in infected protists.

  12. Giant South Brae platform installed

    SciTech Connect

    Cranfield, J.

    1982-12-01

    During the summer 1982 another giant production platform was installed in the North Sea in Marathon's South Brae field. The complex structure of that field necessitated careful planning of the offshore producing structure design and placement. The platform has 46 well slots; 19 will be used as producing wells, 3 for gas injection, and 14 for water injection. The remainder of the well slots are reserved for future development. The platform structure design is examined.

  13. Giant magnetoresistance in silicene nanoribbons.

    PubMed

    Xu, Chengyong; Luo, Guangfu; Liu, Qihang; Zheng, Jiaxin; Zhang, Zhimeng; Nagase, Shigeru; Gao, Zhengxiang; Lu, Jing

    2012-05-21

    By performing first-principle quantum transport calculations, we predict a giant magnetoresistance in zigzag silicene nanoribbons (ZSiNRs) connecting two semi-infinite silicene electrodes through switch of the edge spin direction of ZSiNRs. Spin-filter efficiency of both the antiferromagnetic and ferromagnetic ZSiNRs is sign-changeable with the bias voltage. Therefore, potential application of silicene in spintronics devices is suggested.

  14. A giant juvenile nasopharyngeal angiofibroma.

    PubMed

    Yüce, Salim; Uysal, Ismail Önder; Doğan, Mansur; Polat, Kerem; Salk, Ismail; Müderris, Suphi

    2013-05-01

    Juvenile nasopharyngeal angiofibromas are locally growing and highly vascular tumors. They are primarily treated through surgical excision ranging from an open approach to an endoscopic approach. We presented a 20-year-old man with a giant juvenile nasopharyngeal angiofibroma that bilaterally obliterated the pterygopalatine fossa, invaded the sphenoid bone, and extended to the left nasal passage. His complaints were epistaxis and nasal obstruction. After embolization, the patient was treated surgically using the endoscopic approach and declared cured and discharged without any complications.

  15. A Giant Juvenile Nasopharyngeal Angiofibroma

    PubMed Central

    Yüce, Salim; Uysal, İsmail Önder; Doğan, Mansur; Polat, Kerem; Şalk, İsmail; Müderris, Suphi

    2012-01-01

    Juvenile nasopharyngeal angiofibroma (JNA) are locally growing highly vascular tumours. They are treated primarily by surgical excision ranging from open approach to endoscopic approach. We presented a 20-year-old male with a giant nasopharyngeal juvenile angiofibroma obliterating the pterygopalatine fossa bilaterally, invasing the sphenoid bone and extending to the left nasal passage. His complaints were epistaxis and nasal obstruction. After embolization, the patient was treated surgically with endoscopic approach and discharged as cured without any complication. PMID:23714961

  16. Optical resonator

    NASA Technical Reports Server (NTRS)

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

    2006-01-01

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

  17. Formation of [4Fe-4S] clusters in the mitochondrial iron-sulfur cluster assembly machinery.

    PubMed

    Brancaccio, Diego; Gallo, Angelo; Mikolajczyk, Maciej; Zovo, Kairit; Palumaa, Peep; Novellino, Ettore; Piccioli, Mario; Ciofi-Baffoni, Simone; Banci, Lucia

    2014-11-19

    The generation of [4Fe-4S] clusters in mitochondria critically depends, in both yeast and human cells, on two A-type ISC proteins (in mammals named ISCA1 and ISCA2), which perform a nonredundant functional role forming in vivo a heterocomplex. The molecular function of ISCA1 and ISCA2 proteins, i.e., how these proteins help in generating [4Fe-4S] clusters, is still unknown. In this work we have structurally characterized the Fe/S cluster binding properties of human ISCA2 and investigated in vitro whether and how a [4Fe-4S] cluster is assembled when human ISCA1 and ISCA2 interact with the physiological [2Fe-2S](2+) cluster-donor human GRX5. We found that (i) ISCA2 binds either [2Fe-2S] or [4Fe-4S] cluster in a dimeric state, and (ii) two molecules of [2Fe-2S](2+) GRX5 donate their cluster to a heterodimeric ISCA1/ISCA2 complex. This complex acts as an "assembler" of [4Fe-4S] clusters; i.e., the two GRX5-donated [2Fe-2S](2+) clusters generate a [4Fe-4S](2+) cluster. The formation of the same [4Fe-4S](2+) cluster-bound heterodimeric species is also observed by having first one [2Fe-2S](2+) cluster transferred from GRX5 to each individual ISCA1 and ISCA2 proteins to form [2Fe-2S](2+) ISCA2 and [2Fe-2S](2+) ISCA1, and then mixing them together. These findings imply that such heterodimeric complex is the functional unit in mitochondria receiving [2Fe-2S] clusters from hGRX5 and assembling [4Fe-4S] clusters before their transfer to the final target apo proteins.

  18. KEPLER RAPIDLY ROTATING GIANT STARS

    SciTech Connect

    Costa, A. D.; Martins, B. L. Canto; Bravo, J. P.; Paz-Chinchón, F.; Chagas, M. L. das; Leão, I. C.; Oliveira, G. Pereira de; Silva, R. Rodrigues da; Roque, S.; Oliveira, L. L. A. de; Silva, D. Freire da; De Medeiros, J. R.

    2015-07-10

    Rapidly rotating giant stars are relatively rare and may represent important stages of stellar evolution, resulting from stellar coalescence of close binary systems or accretion of substellar companions by their hosting stars. In the present Letter, we report 17 giant stars observed in the scope of the Kepler space mission exhibiting rapid rotation behavior. For the first time, the abnormal rotational behavior for this puzzling family of stars is revealed by direct measurements of rotation, namely from photometric rotation period, exhibiting a very short rotation period with values ranging from 13 to 55 days. This finding points to remarkable surface rotation rates, up to 18 times the rotation of the Sun. These giants are combined with six others recently listed in the literature for mid-infrared (IR) diagnostics based on Wide-field Infrared Survey Explorer information, from which a trend for an IR excess is revealed for at least one-half of the stars, but at a level far lower than the dust excess emission shown by planet-bearing main-sequence stars.

  19. Hairpin Furans and Giant Biaryls.

    PubMed

    Geng, Xin; Mague, Joel T; Donahue, James P; Pascal, Robert A

    2016-05-01

    The thermal reaction of two cyclopentadienones with 5,5'-binaphthoquinone or 6,6'-dimethoxy-5,5'-binaphthoquinone in refluxing nitrobenzene (210 °C) gives, in a single synthetic step that includes two Diels-Alder additions, two decarbonylations, and two dehydrogenations, giant biaryl bisquinones (compounds 13, 14, 15, 18, and 21). However, when two cyclopentadienones react with 6,6'-dimethoxy-5,5'-binaphthoquinone in nitrobenzene at higher temperatures (250-260 °C), the resulting products are molecular ribbons composed of two twisted aromatic systems fused to a heteropentahelicene (19, 20, and 22). These molecules are representatives of a new class of chiral polycyclic aromatic compounds, the "hairpin furans". Interestingly, reheating a dimethoxy-substituted giant biaryl (e.g., 21) in nitrobenzene at 260 °C does not yield the corresponding hairpin furan (22), and mechanistic studies indicate that some intermediate or byproduct of the synthesis of the giant biaryls is a reagent or catalyst necessary for the conversion of the dimethoxybiaryl to the furan.

  20. Observed Properties of Giant Cells

    NASA Technical Reports Server (NTRS)

    Hathaway, David H.; Upton, Lisa; Colegrove, Owen

    2014-01-01

    The existence of Giant Cells has been suggested by both theory and observation for over 45 years. We have tracked the motions of supergranules in SDO/HMI Doppler velocity data and find larger (Giant Cell) flows that persist for months. The flows in these cells are clockwise around centers of divergence in the north and counter-clockwise in the south. Equatorward flows are correlated with prograde flows - giving the transport of angular momentum toward the equator that is needed to maintain the Sun's rapid equatorial rotation. The cells are most pronounced at mid- and high-latitudes where they exhibit the rotation rates representative of those latitudes. These are clearly large, long-lived, cellular features, with the dynamical characteristics expected from the effects of the Sun's rotation, but the shapes of the cells are not well represented in numerical models. While the Giant Cell flow velocities are small (<10 m/s), their long lifetimes should nonetheless substantially impact the transport of magnetic flux in the Sun's near surface layers.

  1. Red Giants and Solar Sails

    NASA Astrophysics Data System (ADS)

    Matloff, G. L.

    Our Sun will eventually leave the main sequence and expand in size and luminosity to become a giant star. For much of its ~108 year career as a giant, the Sun will reside on the horizontal branch of the Hertzsprung-Russell diagram, with a surface temperature of ~5000 K, a radius about 10x its present-day radius, and about 50x its current luminosity. A space-manufactured beryllium solar-photon sail could be used for emigration from the solar system during this solar phase. Space environmental effects limit the closest approach distance to the giant star to around 0.5 AU, assuming the quiet phase of the stellar activity cycle. Beryllium spectral reflectivity values are used to calculate a wavelength averaged sail spectral reflectivity. This parameter and a reasonable value of spacecraft areal mass thickness (8.87 x 10-5 kg/m2) are used to estimate the interstellar cruise velocity for a sail fully unfurled at a 0.5-1 AU perihelion from an initially parabolic orbit that is always oriented normal to the star. These will be 2-3x greater than those possible for the same craft launched from today's Sun.

  2. Rapid improvement in visual loss with cabergoline treatment in a giant prolactinoma case: 5 years survey.

    PubMed

    Tasan, Ertugrul; Hanimoglu, Hakan; Turgut, Seda; Ilhan, Mahmut Muzaffer; Evran, Sevket; Kaynar, Mehmet Yasar

    2015-01-01

    Giant prolactinoma is a rare subset of macroadenomas. Limited studies demonstrated which therapy could be successfully used in the first-line therapy of giant prolactinoma. We presented a case with a 54 × 40 × 40 mm pituitary adenoma and optic chiasmatic compression with left sphenoid sinus invasion. The tumor caused a loss of visual field of the right side. Cabergoline treatment was started with dose of 1.5 mg/week. Fifteen days later, the clinical visual acuity examination showed a significant improvement in the patient with visual field defect. After the five years follow-up magnetic resonance imagining showed reduction of the adenoma size (17 × 12 mm) was significant. Our findings suggest that, cabergoline can be used as a first-line therapy in giant prolactinomas because tumoral shrinkage without a surgical procedure and rapid improvement in visual field defect is achieved with this medical treatment.

  3. Renierite, Cu10ZnGe2Fe4S16-Cu11GeAsFe4S16: a coupled solid solution series.

    USGS Publications Warehouse

    Bernstein, L.R.

    1986-01-01

    The composition of renierite is found to be Cu10(Zn1-xCux)Ge2-xAsxFe4S16 (0 = or < x = or < 1), with continuous solid solution between the zincian and arsenian end-members, Cu10ZnGe2Fe4S16 and Cu11GeAsFe4S16, through the coupled substitution Zn(II) + Ge(IV) = Cu(I) + As(V). This is the first reported example of extensive coupled solid solution in a sulphide mineral. Arsenian renierite, not previously characterized, is similar to zincian renierite in polished section, with a slightly redder colour and lower anisotropy. It is reddish orange with relief very similar to that of bornite, though it is harder (VHN25 = 286) and does not tarnish in air. It is slightly bireflective, with colours varying from orange-yellow to reddish orange in nearly crossed polarizers. The strongest powder XRD lines are: 3.042(100), 1.861(29), 1.869(16), 1.594(11) and 1.017(10) A; D(calc.) 4.50 g/cm3. Specimens have been found at the Ruby Creek copper deposit, Alaska, where zincian renierite also occurs, and at the Inexco no. 1 mine, Jamestown, Colorado.-J.A.Z.

  4. Non-random association between alleles detected at D4S95 and D4S98 and the Huntington's disease gene.

    PubMed Central

    Theilmann, J; Kanani, S; Shiang, R; Robbins, C; Quarrell, O; Huggins, M; Hedrick, A; Weber, B; Collins, C; Wasmuth, J J

    1989-01-01

    Analysis of many families with linked DNA markers has provided support for the Huntington's disease (HD) gene being close to the telomere on the short arm of chromosome 4. However, analysis of recombination events in particular families has provided conflicting results about the precise location of the HD gene relative to these closely linked DNA markers. Here we report an investigation of linkage disequilibrium between six DNA markers and the HD gene in 75 separate families of varied ancestry. We show significant non-random association between alleles detected at D4S95 and D4S98 and the mutant gene. These data suggest that it may be possible to construct high and low risk haplotypes, which may be helpful in DNA analysis and genetic counselling for HD, and represent independent evidence that the gene for HD is centromeric to more distally located DNA markers such as D4S90. This information may be helpful in defining a strategy to clone the gene for HD based on its location in the human genome. Images PMID:2531224

  5. Dipole Resonances in 4He

    SciTech Connect

    Matsumoto, E.; Nakayama, S.; Hayami, R.; Fushimi, K.; Kawasuso, H.; Yasuda, K.; Yamagata, T.; Akimune, H.; Ikemizu, H.; Fujiwara, M.; Yosoi, M.; Nakanishi, K.; Kawase, K.; Hashimoto, H.; Oota, T.; Sagara, K.; Kudoh, T.; Asaji, S.; Ishida, T.; Tanaka, M.

    2007-02-26

    We investigated the analogs of the giant dipole resonance (GDR) and spin-dipole resonance (SDR) of 4He by using the 4He(7Li,7Be) reaction at an incident energy of 455 MeV and at forward scattering angles. The {delta}S=0 and {delta}S=1 spectra for 4He were obtained by measuring the 0.43-MeV 7Be {gamma}-ray in coincidence with the scattered 7Be. From the {delta}S=0 and {delta}S=1 spectra thus obtained, the strength distributions of the GDR and SDR in 4He can be derived and the results are compared with the previous data.

  6. Hot super-Earths and giant planet cores from different migration histories

    NASA Astrophysics Data System (ADS)

    Cossou, Christophe; Raymond, Sean N.; Hersant, Franck; Pierens, Arnaud

    2014-09-01

    Planetary embryos embedded in gaseous protoplanetary disks undergo Type I orbital migration. Migration can be inward or outward depending on the local disk properties but, in general, only planets more massive than several M⊕ can migrate outward. Here we propose that an embryo's migration history determines whether it becomes a hot super-Earth or the core of a giant planet. Systems of hot super-Earths (or mini-Neptunes) form when embryos migrate inward and pile up at the inner edge of the disk. Giant planet cores form when inward-migrating embryos become massive enough to switch direction and migrate outward. We present simulations of this process using a modified N-body code, starting from a swarm of planetary embryos. Systems of hot super-Earths form in resonant chains with the innermost planet at or interior to the disk inner edge. Resonant chains are disrupted by late dynamical instabilities triggered by the dispersal of the gaseous disk. Giant planet cores migrate outward toward zero-torque zones, which move inward and eventually disappear as the disk disperses. Giant planet cores migrate inward with these zones and are stranded at ~1-5 AU. Our model reproduces several properties of the observed extra-solar planet populations. The frequency of giant planet cores increases strongly when the mass in solids is increased, consistent with the observed giant exoplanet - stellar metallicity correlation. The frequency of hot super-Earths is not a function of stellar metallicity, also in agreement with observations. Our simulations can reproduce the broad characteristics of the observed super-Earth population.

  7. Guiding the Giant

    NASA Astrophysics Data System (ADS)

    1998-08-01

    New ESO Survey Provides Targets for the VLT Giant astronomical telescopes like the ESO Very Large Telescope (VLT) must be used efficiently. Observing time is expensive and there are long waiting lines of excellent research programmes. Thus the work at the telescope must be very well prepared and optimized as much as possible - mistakes should be avoided and no time lost! Astronomers working with the new 8-m class optical/infrared telescopes must base their observations on detailed lists of suitable target objects if they want to perform cutting-edge science. This is particularly true for research programmes that depend on observations of large samples of comparatively rare, distant objects. This type of work requires that extensive catalogues of such objects must be prepared in advance. One such major catalogue - that will serve as a very useful basis for future VLT observations - has just become available from the new ESO Imaging Survey (EIS). The Need for Sky Surveys Astronomers have since long recognized the need to carry out preparatory observations with other telescopes in order to "guide" large telescopes. To this end, surveys of smaller or larger parts of the sky have been performed by wide-field telescopes, paving the way for subsequent work at the limits of the largest available ground-based telescopes. For instance, a complete photographic survey of the sourthern sky (declination < -17.5°) was carried out in the 1970's with the ESO 1-metre Schmidt Telescope in support of the work at the 3.6-m telescope at the ESO La Silla observatory. However, while until recently most observational programmes could rely on samples of objects found on photographic plates, this is no longer possible. New image surveys must match the fainter limiting magnitudes reached by the new and larger telescopes. Modern digital, multi-colour, deep imaging surveys have thus become an indispensable complement to the 8-m telescopes. The new generation of imaging surveys will, without

  8. The Obliquities of the Giant Planets

    NASA Astrophysics Data System (ADS)

    Hamilton, D. P.; Ward, Wm. R.

    2002-09-01

    Jupiter has by far the smallest obliquity ( ~ 3o) of the planets (not counting tidally de-spun Mercury and Venus) which may be reflective of its formation by hydrodynamic gas flow rather than stochastic impacts. Saturn's obliquity ( ~ 26o), however, seems to belie this simple formation picture. But since the spin angular momentum of any planet is much smaller than its orbital angular momentum, post-formation obliquity can be strongly modified by passing through secular spin-orbit resonances, i.e., when the spin axis precession rate of the planet matches one of the frequencies describing the precession of the orbit plane. Spin axis precession is due to the solar torque on both the oblate figure of the planet and any orbiting satellites. In the case of Jupiter, the torque on the Galilean satellites is the principal cause of its 4.5*105 year precession; Saturn's precession of 1.8*106 years is dominated by Titan. In the past, the planetary spin axis precession rates should have been much faster due to the massive circumplanetary disks from which the current satellites condensed. The regression of the orbital node of a planet is due to the gravitational perturbations of the other planets. Nodal regression is not uniform, but is instead a composite of the planetary system's normal modes. For Jupiter and Saturn, the principal frequency is the nu16, with a period of ~ 49,000 years; the amplitude of this term is I ~ 0o.36 for Jupiter and I ~ 0o.90 for Saturn. In spite of the small amplitudes, slow adiabatic passages through this resonance (due to circumplanetary disk dispersal) could increase planetary obliquities from near zero to ~ [tan1/3 I] ~ 10o. We will discuss scenarios in which giant planet obliquities are affected by this and other resonances, and will use Jupiter's low obliquity to constrain the mass and duration of a satellite precursor disk. DPH acknowledges support from NSF Career Grant AST 9733789 and WRW is grateful to the NASA OSS and PGG programs.

  9. Red giants: then and now

    NASA Astrophysics Data System (ADS)

    Faulkner, John

    Fred Hoyle's work on the structure and evolution of red giants, particularly his pathbreaking contribution with Martin Schwarzschild (Hoyle and Schwarzschild 1955), is both lauded and critically assessed. In his later lectures and work with students in the early 1960s, Hoyle presented more physical ways of understanding some of the approximations used, and results obtained, in that seminal paper. Although later ideas by other investigators will be touched upon, Hoyle's viewpoint - that low-mass red giants are essentially white dwarfs with a serious mass-storage problem - is still extremely fruitful. Over the years, I have further developed his method of attack. Relatively recently, I have been able to deepen and broaden the approach, finally extending the theory to provide a unifying treatment of the structure of low-mass stars from the main sequence though both the red-giant and horizontal-branch phases of evolution. Many aspects of these stars that had remained puzzling, even mysterious, for decades have now fallen into place, and some questions have been answered that were not even posed before. With low-mass red giants as the simplest example, this recent work emphasizes that stars, in general, may have at least two distinct but very important centres: (I) a geometrical centre, and (II) a separate nuclear centre, residing in a shell outside a zero-luminosity dense core for example. This two-centre perspective leads to an explicit, analytical, asymptotic theory of low-mass red-giant structure. It enables one to appreciate that the problem of understanding why such stars become red giants is one of anticipating a remarkable yet natural structural bifurcation that occurs in them. This bifurcation occurs because of a combination of known and understandable facts just summarized namely that, following central hydrogen exhaustion, a thin nuclear-burning shell does develop outside a more-or-less dense core. In the resulting theory, both ρsh/ρolinec and

  10. Spontaneous thrombosis in giant intracranial aneurysms.

    PubMed Central

    Whittle, I R; Dorsch, N W; Besser, M

    1982-01-01

    Twelve patients in a series of 22 with giant intracranial aneurysms demonstrated neuroradiological features of partial or total spontaneous intra-aneurysmal thrombosis. The presence of this intra-aneurysmal clot significantly altered the computed tomographic appearance of the giant aneurysm. Massive intra-aneurysmal thrombosis did not protect against subarachnoid haemorrhage and the likelihood of rupture of a clot containing giant aneurysm was not significantly different from that of a non-thrombosed giant aneurysm. Although parent artery occlusion from a thrombosed giant aneurysm, and massive aneurysmal thrombosis leading to the formation of giant serpentine aneurysm were documented, these are rare epiphenomena. The risk of embolisation from a partially thrombosed giant aneurysm, which was documented in one case, would appear to be greater than that from a non-thrombosed giant aneurysm. The findings in this series, and a review of literature, suggest that the presence of intra-aneurysmal clot in giant intracranial aneurysms has little prognostic significance and does not alter the management or outcome after treatment. Images PMID:7175528

  11. Speciation and phylogeography of giant petrels Macronectes.

    PubMed

    Techow, N M S M; O'Ryan, C; Phillips, R A; Gales, R; Marin, M; Patterson-Fraser, D; Quintana, F; Ritz, M S; Thompson, D R; Wanless, R M; Weimerskirch, H; Ryan, P G

    2010-02-01

    We examine global phylogeography of the two forms of giant petrel Macronectes spp. Although previously considered to be a single taxon, and despite debate over the status of some populations and the existence of minimal genetic data (one mitochondrial cytochrome b sequence per form), the current consensus based on morphology is that there are two species, Northern Giant Petrel M. halli and Southern Giant Petrel M. giganteus. This study examined genetic variation at cytochrome b as well as six microsatellite loci in giant petrels from 22 islands, representing most island groups at which the two species breed. Both markers support separate species status, although sequence divergence in cytochrome b was only 0.42% (corrected). Divergence was estimated to have occurred approximately 0.2mya, but with some colonies apparently separated for longer (up to 0.5 my). Three clades were found within giant petrels, which separated approximately 0.7mya, with the Southern Giant Petrel paraphyletic to a monophyletic Northern Giant Petrel. There was evidence of past fragmentation during the Pleistocene, with subsequent secondary contact within Southern Giant Petrels. The analysis also suggested a period of past population expansion that corresponded roughly to the timing of speciation and the separation of an ancestral giant petrel population from the fulmar Fulmarus clade. PMID:19755164

  12. Stochastic resonance

    NASA Astrophysics Data System (ADS)

    Gammaitoni, Luca; Hänggi, Peter; Jung, Peter; Marchesoni, Fabio

    1998-01-01

    Over the last two decades, stochastic resonance has continuously attracted considerable attention. The term is given to a phenomenon that is manifest in nonlinear systems whereby generally feeble input information (such as a weak signal) can be be amplified and optimized by the assistance of noise. The effect requires three basic ingredients: (i) an energetic activation barrier or, more generally, a form of threshold; (ii) a weak coherent input (such as a periodic signal); (iii) a source of noise that is inherent in the system, or that adds to the coherent input. Given these features, the response of the system undergoes resonance-like behavior as a function of the noise level; hence the name stochastic resonance. The underlying mechanism is fairly simple and robust. As a consequence, stochastic resonance has been observed in a large variety of systems, including bistable ring lasers, semiconductor devices, chemical reactions, and mechanoreceptor cells in the tail fan of a crayfish. In this paper, the authors report, interpret, and extend much of the current understanding of the theory and physics of stochastic resonance. They introduce the readers to the basic features of stochastic resonance and its recent history. Definitions of the characteristic quantities that are important to quantify stochastic resonance, together with the most important tools necessary to actually compute those quantities, are presented. The essence of classical stochastic resonance theory is presented, and important applications of stochastic resonance in nonlinear optics, solid state devices, and neurophysiology are described and put into context with stochastic resonance theory. More elaborate and recent developments of stochastic resonance theory are discussed, ranging from fundamental quantum properties-being important at low temperatures-over spatiotemporal aspects in spatially distributed systems, to realizations in chaotic maps. In conclusion the authors summarize the achievements

  13. Asteroseismology of red-giant stars as a novel approach in the search for gravitational waves

    NASA Astrophysics Data System (ADS)

    Campante, Tiago L.; Lopes, Ilídio; Bossini, Diego; Miglio, Andrea; Chaplin, William J.

    2015-08-01

    Stars are massive resonators that may in principle be used as gravitational-wave (GW) detectors with an isotropic sensitivity. New insights on stellar physics have been made possible by asteroseismology, the study of stars by the observation of their natural, resonant oscillations. The continuous monitoring of oscillation modes in stars of different masses and sizes (e.g., as carried out by NASA’s Kepler space telescope) thus opens the possibility of surveying the local Universe for GW radiation. Red-giant stars are of particular interest in this regard. Since the mean separation between red giants in open clusters is small (of a few light years), this can in principle be used to look for the same GW imprint on the oscillation modes of different stars as a GW propagates across the cluster. Furthermore, the frequency range probed by oscillations in red giants overlaps with, and complements, the capabilities of the planned eLISA space interferometer. We propose asteroseismology of red-giant stars as a novel approach in the search for gravitational waves and assess to what extent oscillations in these stars can be excited by a passing, monochromatic GW.

  14. Origin of the orbital architecture of the giant planets of the Solar System.

    PubMed

    Tsiganis, K; Gomes, R; Morbidelli, A; Levison, H F

    2005-05-26

    Planetary formation theories suggest that the giant planets formed on circular and coplanar orbits. The eccentricities of Jupiter, Saturn and Uranus, however, reach values of 6 per cent, 9 per cent and 8 per cent, respectively. In addition, the inclinations of the orbital planes of Saturn, Uranus and Neptune take maximum values of approximately 2 degrees with respect to the mean orbital plane of Jupiter. Existing models for the excitation of the eccentricity of extrasolar giant planets have not been successfully applied to the Solar System. Here we show that a planetary system with initial quasi-circular, coplanar orbits would have evolved to the current orbital configuration, provided that Jupiter and Saturn crossed their 1:2 orbital resonance. We show that this resonance crossing could have occurred as the giant planets migrated owing to their interaction with a disk of planetesimals. Our model reproduces all the important characteristics of the giant planets' orbits, namely their final semimajor axes, eccentricities and mutual inclinations.

  15. Origin of the orbital architecture of the giant planets of the Solar System.

    PubMed

    Tsiganis, K; Gomes, R; Morbidelli, A; Levison, H F

    2005-05-26

    Planetary formation theories suggest that the giant planets formed on circular and coplanar orbits. The eccentricities of Jupiter, Saturn and Uranus, however, reach values of 6 per cent, 9 per cent and 8 per cent, respectively. In addition, the inclinations of the orbital planes of Saturn, Uranus and Neptune take maximum values of approximately 2 degrees with respect to the mean orbital plane of Jupiter. Existing models for the excitation of the eccentricity of extrasolar giant planets have not been successfully applied to the Solar System. Here we show that a planetary system with initial quasi-circular, coplanar orbits would have evolved to the current orbital configuration, provided that Jupiter and Saturn crossed their 1:2 orbital resonance. We show that this resonance crossing could have occurred as the giant planets migrated owing to their interaction with a disk of planetesimals. Our model reproduces all the important characteristics of the giant planets' orbits, namely their final semimajor axes, eccentricities and mutual inclinations. PMID:15917800

  16. Hydrogeologic Assessment of the 4-S Land and Cattle CompanyRanch

    SciTech Connect

    Quinn, Nigel W.T.

    2006-04-10

    Hydrogeological assessment of the 4-S Land and Cattle Company (4-S Ranch) was conducted using a combination of field investigations and a survey of available literature from nearby agricultural water districts and other entities. The 4-S Ranch has been able to meet most of its own water needs providing irrigated pasture for beef cattle by an active program of shallow groundwater pumping in these miconfined aquifer above the Corcoran Clay. Comparison of groundwater pumping on the 4-S Ranch property with groundwater pumping in the adjacent Merquin and Stevinson Water Districts shows great similarity in the well screened depths and the quality of the groundwater produced by the well fields. The pump yield for the eight active production wells on the 4-S property are comparable to the production and drainage wells in the adjacent water districts. Like these Districts the 4-S Ranch lies close to the Valley trough in a historic discharge area. The 4-S Ranch is unique in that it is bounded and bisected by several major water conveyance facilities including Bear Creek. Although the large number of potential recharge structures would suggest significant groundwater conjunctive use potential the major well field development has occurred along the length of the Eastside Canal. The Eastside Canal is known to be leaky above the ''A'' Clay the Canal passes through sandy areas and experiences significant groundwater seepage. This seepage can be intercepted by adjacent groundwater wells. Pumping adjacent to, and along the alignment of the Canal, may induce higher rates of seepage from the Eastside Canal. Groundwater quality below and adjacent to the Eastside Canal is very good, reflecting the origin of this diverted water from the Merced River. Most of the pumpage occurs in a depth interval between 30 ft and 130 ft. Safe yield estimates made using the available data show that the 4-S Ranch has sufficient resources to meet its own needs. Further exploitation of the groundwater will

  17. Experimental and Computational Prediction of the Hydrogen Transport Properties of Pd4S

    SciTech Connect

    Morreale, B.D.; Howard, B.H.; Iyoha, O.; Enick, R.M.; Ling, C.; Sholl, D.S.

    2007-09-12

    Computational and experimental methods were used to quantify the apparent influence of a Pd4S corrosion product resulting from flux testing of 100-micron thick pure palladium membranes in a 0.1%H2S-10%He-H2 retentate gas mixture. The permeability of Pd4S was estimated to be approximately 20 times less than that of pure palladium from the results obtained through sulfide growth kinetics using gravimetric methods and the observed H2 flux decay during permeability characterization from 623 to 908 K. To complement experimental analysis, density functional theory was used to predict the hydrogen permeability of Pd4S by examining diffusivity and solubility of H in bulk Pd4S. Results are in good agreement between the experimental and computational prediction of the activation energy of permeation, while only in moderate agreement when comparing the hydrogen permeability of Pd4S. The permeability values obtained through experimentation were approximately 7 times greater than the computational predictions.

  18. Protonation and Proton-Coupled Electron Transfer at S-Ligated [4Fe-4S] Clusters

    PubMed Central

    Morris, Wesley D.; Darcy, Julia W.; Mayer, James M.

    2015-01-01

    Biological [Fe-S] clusters are increasingly recognized to undergo proton-coupled electron transfer (PCET), but the site of protonation, mechanism, and role for PCET remains largely unknown. Here we explore this reactivity with synthetic model clusters. Protonation of the arylthiolate-ligated [4Fe-4S] cluster [Fe4S4(SAr)4]2- (1, SAr = S-2,4-6-(iPr)3C6H2) leads to thiol dissociation, reversibly forming [Fe4S4(SAr)3L]1- (2) + ArSH (L = solvent, and/or conjugate base). Solutions of 2 + ArSH react with the nitroxyl radical TEMPO to give [Fe4S4(SAr)4]1- (1ox) and TEMPOH. This reaction involves PCET coupled to thiolate association and may proceed via the unobserved protonated cluster [Fe4S4(SAr)3(HSAr)]1-(1-H). Similar reactions with this and related clusters proceed comparably. An understanding of the PCET thermochemistry of this cluster system has been developed, encompassing three different redox levels and two protonation states. PMID:25965413

  19. Protonation and Proton-Coupled Electron Transfer at S-Ligated [4Fe-4S] Clusters.

    PubMed

    Saouma, Caroline T; Morris, Wesley D; Darcy, Julia W; Mayer, James M

    2015-06-15

    Biological [Fe-S] clusters are increasingly recognized to undergo proton-coupled electron transfer (PCET), but the site of protonation, mechanism, and role for PCET remains largely unknown. Here we explore this reactivity with synthetic model clusters. Protonation of the arylthiolate-ligated [4Fe-4S] cluster [Fe4 S4 (SAr)4 ](2-) (1, SAr=S-2,4-6-(iPr)3 C6 H2 ) leads to thiol dissociation, reversibly forming [Fe4 S4 (SAr)3 L](1-) (2) and ArSH (L=solvent, and/or conjugate base). Solutions of 2+ArSH react with the nitroxyl radical TEMPO to give [Fe4 S4 (SAr)4 ](1-) (1ox ) and TEMPOH. This reaction involves PCET coupled to thiolate association and may proceed via the unobserved protonated cluster [Fe4 S4 (SAr)3 (HSAr)](1-) (1-H). Similar reactions with this and related clusters proceed comparably. An understanding of the PCET thermochemistry of this cluster system has been developed, encompassing three different redox levels and two protonation states. PMID:25965413

  20. Warm Disks from Giant Impacts

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2015-10-01

    In the process of searching for exoplanetary systems, weve discovered tens of debris disks close around distant stars that are especially bright in infrared wavelengths. New research suggests that we might be looking at the late stages of terrestrial planet formation in these systems.Forming Terrestrial PlanetsAccording to the widely-accepted formation model for our solar-system, protoplanets the size of Mars formed within a protoplanetary disk around our Sun. Eventually, the depletion of the gas in the disk led the orbits of these protoplanets to become chaotically unstable. Finally, in the giant impact stage, many of the protoplanets collided with each other ultimately leading to the formation of the terrestrial planets and their moons as we know them today.If giant impact stages occur in exoplanetary systems, too leading to the formation of terrestrial exoplanets how would we detect this process? According to a study led by Hidenori Genda of the Tokyo Institute of Technology, we might be already be witnessing this stage in observations of warm debris disks around other stars. To test this, Genda and collaborators model giant impact stages and determine what we would expect to see from a system undergoing this violent evolution.Modeling CollisionsSnapshots of a giant impact in one of the authors simulations. The collision causes roughly 0.05 Earth masses of protoplanetary material to be ejected from the system. Click for a closer look! [Genda et al. 2015]The collaborators run a series of simulations evolving protoplanetary bodies in a solar system. The simulations begin 10 Myr into the lifetime of the solar system, i.e., after the gas from the protoplanetary disk has had time to be cleared and the protoplanetary orbits begin to destabilize. The simulations end when the protoplanets are done smashing into each other and have again settled into stable orbits, typically after ~100 Myr.The authors find that, over an average giant impact stage, the total amount of

  1. Vibration modes of giant gravitons

    SciTech Connect

    Das, Sumit R.; Jevicki, Antal; Mathur, Samir D.

    2001-01-15

    We examine the spectrum of small vibrations of giant gravitons when the gravitons expand in anti--de Sitter space and when they expand on the sphere. For any given angular harmonic, the modes are found to have frequencies related to the curvature length scale of the background; these frequencies are independent of radius (and hence angular momentum) of the brane itself. This implies that the holographic dual theory must have, in a given R charge sector, low-lying non-BPS excitations with level spacings independent of the R charge.

  2. Giant Sigmoid Diverticula: A Review

    PubMed Central

    Kempczinski, Richard F.; Ferrucci, Joseph T.

    1974-01-01

    Two patients with giant sigmoid diverticula are added to 13 cases reported in the literature and the clinical features of this rare complication of diverticulosis are reviewed. These lesions probably arise as pseudodiverticula of the sigmoid colon with herniation of the mucosa through the muscle wall. They become progressively inflated by colonic gas via a ball-valve type mechanism. They are best treated by resection of the diverticulum, in continuity with the involved sigmoid, and primary anastomosis. ImagesFig. 1.Fig. 2.Fig. 3. PMID:4433171

  3. Structural analysis of the S4-S5 linker of the human KCNQ1 potassium channel.

    PubMed

    Gayen, Shovanlal; Li, Qingxin; Kang, CongBao

    2015-01-01

    KCNQ1 plays important roles in the cardiac action potential and consists of an N-terminal domain, a voltage-sensor domain, a pore domain and a C-terminal domain. KCNQ1 is a voltage-gated potassium channel and its channel activity is regulated by membrane potentials. The linker between transmembrane helices 4 and 5 (S4-S5 linker) is important for transferring the conformational changes from the voltage-sensor domain to the pore domain. In this study, the structure of the S4-S5 linker of KCNQ1 was investigated by solution NMR, circular dichroism and fluorescence spectroscopic studies. The S4-S5 linker adopted a helical structure in detergent micelles. The W248 may interact with the cell membrane.

  4. Giant Quenching of Spin-Orbit Interaction of Ga1-xVxP Crystals

    NASA Astrophysics Data System (ADS)

    Zhao, Min-Guang

    2003-12-01

    We prove the presence of a giant quenching of the spin-orbit coupling of V 2+ ion in GaP on the basis of a trigonal crystal field model and a complete diagonalization procedure. The calculated result is in good agreement with the experimental data of the thermally detected electron paramagnetic resonance. It was also shown that the dynamical Jahn-Teller explanation cannot be excluded.

  5. Bulk superconductivity in bismuth oxysulfide Bi4O4S3.

    PubMed

    Singh, Shiva Kumar; Kumar, Anuj; Gahtori, Bhasker; Shruti; Sharma, Gyaneshwar; Patnaik, Satyabrata; Awana, Veer P S

    2012-10-10

    A very recent report on the observation of superconductivity in Bi(4)O(4)S(3) [Mizuguchi, Y.; http://arxiv.org/abs/1207.3145] could potentially reignite the search for superconductivity in a broad range of layered sulfides. We report here the synthesis of Bi(4)O(4)S(3) at 500 °C by a vacuum encapsulation technique and its basic characterizations. The as-synthesized Bi(4)O(4)S(3) was contaminated with small amounts of Bi(2)S(3) and Bi impurities. The majority phase was found to be tetragonal (space group I4/mmm) with lattice parameters a = 3.9697(2) Å and c = 41.3520(1) Å. Both AC and DC magnetization measurements confirmed that Bi(4)O(4)S(3) is a bulk superconductor with a superconducting transition temperature (T(c)) of 4.4 K. Isothermal magnetization (M-H) measurements indicated closed loops with clear signatures of flux pinning and irreversible behavior. The lower critical field (H(c1)) at 2 K for the new superconductor was found to be ~15 Oe. Magnetotransport measurements showed a broadening of the resistivity (ρ) and a decrease in T(c) (ρ = 0) with increasing magnetic field. The extrapolated upper critical field H(c2)(0) was ~31 kOe with a corresponding Ginzburg-Landau coherence length of ~100 Å . In the normal state, the ρ ~ T(2) dependence was not indicated. Hall resistivity data showed a nonlinear magnetic field dependence. Our magnetization and electrical transport measurements substantiate the appearance of bulk superconductivity in as-synthesized Bi(4)O(4)S(3). On the other hand, Bi heat-treated at the same temperature is not superconducting, thus excluding the possibility of impurity-driven superconductivity in the newly discovered superconductor Bi(4)O(4)S(3).

  6. A Turkish family with Ellis-van Creveld syndrome in six siblings; linkage analysis on 4p16 region (D4S3360-D4S2366).

    PubMed

    Cağdaş, D N; Parlar, A I; Pac, A; Tutun, U; Balci, S

    2008-01-01

    We present a Turkish family and their 6 children, consecutively affected by Ellis-van Creveld (EVC) Syndrome. Four of the affected children died in the postnatal period, and 2 of them had been admitted to the pediatric cardiology department for their cardiologic evaluation. Since they had the features of the EVC Syndrome, linkage analysis was performed with the polymorphic markers, D4S3360-D4S2366, selected from 4p 16 locus. There was complete segregation between the disease and marker allels and the two affected siblings were homozygote for the polymorphic markers, as expected in autosomal recessive inheritance. The diagnosis of EVC Syndrome was confirmed by this molecular analysis. Two cases with EVC were presented in this report. Case 1 had partial abnormal pulmonary venous return and pulmonary stenosis additional to ostium primum atrial septal defect and mitral cleft. Partial abnormal pulmonary venous return and pulmonary stenosis were previously not reported with EVC Syndrome. Postaxial polydactyly phenotype of the Case 2 differs from her brother's. There is bifid 5th metacarpal and unilateral (L) bifid middle and distal phalanges resembling syndactyly.

  7. Classified computer configuration control system (C{sup 4}S), revision 3, user`s information

    SciTech Connect

    O`Callaghan, P.B.; Nelson, R.A.; Grambihler, A.J.

    1994-04-01

    The Classified Computer Configuration Control System (C{sup 4}S) allows security management to track pertinent information concerning classified computer systems in the scope of their control. Information is entered by the level security manager that is closest to the classified computer system. Managers that are further removed from systems can have consolidated information made available to them. C{sup 4}S can be used to generate reports that are as current as the last information that was entered into the database. C{sup 4}S offers data entry, data display, and data reporting. The user interface uses menus, entry forms, the mouse, and Hot Keys. C{sup 4}S provides help windows that are available at any time by pressing the F1 key. C{sup 4}S has help for each menu, data entry form, and general program information. You can browse a help window by pressing the arrows, page up, or page down keys. You control C{sup 4}S with program options selected from pull-down menus. You {open_quotes}select{close_quotes} by moving a highlight bar up and down or across the menu and pressing enter on one of the options. The highlight bar is moved using the arrow keys, mouse, or selection letters. Notice that a letter of each menu option is a different color from the other letters. This is the selection letter for that option. If you press the selection letter, the highlight bar will move to that option. You can also use a mouse to move the highlight bar to the option by moving the mouse pointer to the option and pressing the mouse button. Explanation of menu options or entry fields appear at the bottom of the screen. These explanations should help you use C{sup 4}S. If you need more help, it is available by pressing F1. C{sup 4}S will bring up a help window for the particular option you are working with. The authors of the program are P.B. O`Callaghan, A. J. Grambihler, and R.A. Nelson.

  8. Sodium in weak G-band giants

    NASA Technical Reports Server (NTRS)

    Drake, Jeremy J.; Lambert, David L.

    1994-01-01

    Sodium abundances have been determined for eight weak G-band giants whose atmospheres are greatly enriched with products of the CN-cycling H-burning reactions. Systematic errors are minimized by comparing the weak G-band giants to a sample of similar but normal giants. If, further, Ca is selected as a reference element, model atmosphere-related errors should largely be removed. For the weak-G-band stars (Na/Ca) = 0.16 +/- 0.01, which is just possibly greater than the result (Na/Ca) = 0.10 /- 0.03 from the normal giants. This result demonstrates that the atmospheres of the weak G-band giants are not seriously contaminated with products of ON cycling.

  9. Structure of the Asteroid Belt from the Gas Giants' Growth and Chaotic Dynamics

    NASA Astrophysics Data System (ADS)

    Izidoro, André; Raymond, Sean N.; Pierens, Arnaud; Morbidelli, Alessandro; Winter, Othon; Nesvorny, David

    2016-05-01

    The structure of the asteroid belt holds a record of the Solar System's dynamical history. The current belt only contains 10-3 Earth masses yet the asteroids' orbits are dynamically excited, with a large spread in eccentricity and inclination. The belt is also chemically segregated: the inner belt is dominated by dry S-types and the outer belt by hydrated C-types. Here we propose a new model in which the asteroid belt was always low-mass and was partially populated and sculpted by the giant planets on chaotic, resonant orbits. We first show that the compositional dichotomy of the asteroid belt is a simple consequence of Jupiter's growth in the gaseous protoplanetary disk. As Jupiter's core rapidly grew by accreting gas, orbits of nearby planetesimals were perturbed onto Jupiter-crossing trajectories. A significant fraction (~10%) of objects in the neighborhood exterior of Jupiter's orbit were implanted by gas drag into the outer parts of the asteroid belt as C-types. While the gas giants were likely in mean motion resonance at the end of the gaseous disk phase, we show that small perturbations may have driven them into a chaotic but stable state. After the dissipation of the gaseous disk, stochastic variations in the gas giants orbits caused resonances to chaotically jump across the main belt and excite the asteroids' orbits. Our results suggest that the early Solar System was chaotic and introduce a simple framework to understand the origins of the asteroid belt.

  10. Giant Planets in Open Clusters

    NASA Astrophysics Data System (ADS)

    Quinn, S. N.; White, R. J.; Latham, D. W.

    2015-10-01

    Two decades after the discovery of 51 Peg b, more than 200 hot Jupiters have now been confirmed, but the details of their inward migration remain uncertain. While it is widely accepted that short period giant planets could not have formed in situ, several different mechanisms (e.g., Type II migration, planet-planet scattering, Kozai-Lidov cycles) may contribute to shrinking planetary orbits, and the relative importance of each is not well-constrained. Migration through the gas disk is expected to preserve circular, coplanar orbits and must occur quickly (within ˜ 10 Myr), whereas multi-body processes should initially excite eccentricities and inclinations and may take hundreds of millions of years. Subsequent evolution of the system (e.g., orbital circularization and inclination damping via tidal interaction with the host star) may obscure these differences, so observing hot Jupiters soon after migration occurs can constrain the importance of each mechanism. Fortunately, the well-characterized stars in young and adolescent open clusters (with known ages and compositions) provide natural laboratories for such studies, and recent surveys have begun to take advantage of this opportunity. We present a review of the discoveries in this emerging realm of exoplanet science, discuss the constraints they provide for giant planet formation and migration, and reflect on the future direction of the field.

  11. Giant magnetoresistance in silicene nanoribbons

    NASA Astrophysics Data System (ADS)

    Xu, Chengyong; Luo, Guangfu; Liu, Qihang; Zheng, Jiaxin; Zhang, Zhimeng; Nagase, Shigeru; Gao, Zhengxiang; Lu, Jing

    2012-05-01

    By performing first-principle quantum transport calculations, we predict a giant magnetoresistance in zigzag silicene nanoribbons (ZSiNRs) connecting two semi-infinite silicene electrodes through switch of the edge spin direction of ZSiNRs. Spin-filter efficiency of both the antiferromagnetic and ferromagnetic ZSiNRs is sign-changeable with the bias voltage. Therefore, potential application of silicene in spintronics devices is suggested.By performing first-principle quantum transport calculations, we predict a giant magnetoresistance in zigzag silicene nanoribbons (ZSiNRs) connecting two semi-infinite silicene electrodes through switch of the edge spin direction of ZSiNRs. Spin-filter efficiency of both the antiferromagnetic and ferromagnetic ZSiNRs is sign-changeable with the bias voltage. Therefore, potential application of silicene in spintronics devices is suggested. Electronic supplementary information (ESI) available: The total current contrasts between the AFM and FM configurations and the spin-resolved I-Vbias characteristics in the AFM and FM configurations of all the checked ZSiNRs as a function of bias voltage; the spin-resolved I-Vbias characteristics and SFEs of different-length 5-ZSiNR in the AFM and FM configurations as a function of bias voltage. See DOI: 10.1039/c2nr00037g

  12. Nonfunctioning giant pituitary adenomas: Invasiveness and recurrence

    PubMed Central

    Landeiro, José Alberto; Fonseca, Elissa Oliveira; Monnerat, Andrea Lima Cruz; Taboada, Giselle Fernandes; Cabral, Gustavo Augusto Porto Sereno; Antunes, Felippe

    2015-01-01

    Background: We report our surgical series of 35 patients with giant nonfunctioning pituitary adenomas (GNFPA). We analyzed the rule of Ki-67 antigen expression in predicting recurrence. Methods: Thirty-five patients were operated between 2000 and 2010. Suprassellar extension of the tumors were classified according to Hardy and Mohr based on magnetic resonance (MR) studies. Pituitary endocrine function and MR scans were assessed preoperatively and at 1, 6, and 12 months postoperatively. Immunohistochemical studies were based in regard to the expression of the proliferative Ki-67 index and the hormonal receptor for luteinizing hormone, follicle stimulating hormone, growth hormone, thyroid stimulating hormone, adrenocorticotropic hormone, and prolactin. Tumors specimens were obtained from 35 patients with GNFPA. Endoscopic transsphenoidal surgery was the approach of choice. Results: Thirty-five patients were submitted to 49 surgeries, 44 (89.8%) were transsphenoidal and 5 (10.2%) were transcranial. The most frequent preoperative complaints were visual acuity impairment and visual field defect in 25 (71.2%) and 23 (65.7%) cases, respectively. Improvement of visual acuitiy and visual field deficit after surgery was seen in 20 (80%) and 17 (73.9%) patients, respectively. Endocrinological deficits were encountered in 20 patients (57.1%). After surgery, 18 patients (51.4%) required hormonal replacement. Three patients had visual symptoms related to pituitary apoplexy and recovered after surgery. The Ki-67 labeling index (LI) ranged from <1% to 4.8%. The rate of recurrence in tumors with Ki-67 <3% was 7.7% (2 patients), Ki-67 >3% was present in 5 patients and the recurrence committed 3 patients. Conclusion: In our series, regardless the improvement of visual function and compressing symptoms, 5 patients with expression of Ki-67 LI more than 3% experienced a recurrence. PMID:26674325

  13. Structural phase transition and phonon instability in Cu12Sb4S13

    NASA Astrophysics Data System (ADS)

    May, A. F.; Delaire, O.; Niedziela, J. L.; Lara-Curzio, E.; Susner, M. A.; Abernathy, D. L.; Kirkham, M.; McGuire, M. A.

    2016-02-01

    A structural phase transition has been discovered in the synthetic tetrahedrite Cu12Sb4S13 at approximately 88 K. Upon cooling, the material transforms from its known cubic symmetry to a tetragonal unit cell that is characterized by an in-plane ordering that leads to a doubling of the unit cell volume. Specific heat capacity measurements demonstrate a hysteresis of more than two degrees in the associated anomaly. A similar hysteresis was observed in powder x-ray diffraction measurements, which also indicate a coexistence of the two phases, and together these results suggest a first-order transition. This structural transition coincides with a recently-reported metal-insulator transition, and the structural instability is related to the very low thermal conductivity κ in these materials. Inelastic neutron scattering was used to measure the phonon density of states in Cu12Sb4S13 and Cu10Zn2Sb4S13 , both of which possess a localized, low-energy phonon mode associated with strongly anharmonic copper displacements that suppress κ . In Cu12Sb4S13 , signatures of the phase transition are observed in the temperature dependence of the localized mode, which disappears at the structural transition. In contrast, in the cubic Zn-doped material, the mode is at slightly higher-energy but observable for all temperatures, though it softens upon cooling.

  14. Structural phase transition and phonon instability in Cu12Sb4S13

    DOE PAGES

    May, Andrew F.; Delaire, Olivier A.; Niedziela, Jennifer L.; Lara-Curzio, Edgar; Susner, Michael A.; Abernathy, Douglas L.; Kirkham, Melanie J.; McGuire, Michael A.

    2016-02-08

    In this study, a structural phase transition has been discovered in the synthetic tetrahedrite Cu12Sb4S13 at approximately 88 K. Upon cooling, the material transforms from its known cubic symmetry to a tetragonal unit cell that is characterized by an in-plane ordering that leads to a doubling of the unit cell volume. Specific heat capacity measurements demonstrate a hysteresis of more than two degrees in the associated anomaly. A similar hysteresis was observed in powder x-ray diffraction measurements, which also indicate a coexistence of the two phases, and together these results suggest a first-order transition. This structural transition coincides with amore » recently-reported metal-insulator transition, and the structural instability is related to the very low thermal conductivity κ in these materials. Inelastic neutron scattering was used to measure the phonon density of states in Cu12Sb4S13 and Cu10Zn2Sb4S13, both of which possess a localized, low-energy phonon mode associated with strongly anharmonic copper displacements that suppress κ. In Cu12Sb4S13, signatures of the phase transition are observed in the temperature dependence of the localized mode, which disappears at the structural transition. In contrast, in the cubic Zn-doped material, the mode is at slightly higher-energy but observable for all temperatures, though it softens upon cooling.« less

  15. Role of the S4-S5 linker in CNG channel activation.

    PubMed

    Kusch, Jana; Zimmer, Thomas; Holschuh, Jascha; Biskup, Christoph; Schulz, Eckhard; Nache, Vasilica; Benndorf, Klaus

    2010-10-20

    Cyclic nucleotide-gated (CNG) channels mediate sensory signal transduction in retinal and olfactory cells. The channels are activated by the binding of cyclic nucleotides to a cyclic nucleotide-binding domain (CNBD) in the C-terminus that is located at the intracellular side. The molecular events translating the ligand binding to the pore opening are still unknown. We investigated the role of the S4-S5 linker in the activation process by quantifying its interaction with other intracellular regions. To this end, we constructed chimeric channels in which the N-terminus, the S4-S5 linker, the C-linker, and the CNBD of the retinal CNGA1 subunit were systematically replaced by the respective regions of the olfactory CNGA2 subunit. Macroscopic concentration-response relations were analyzed, yielding the apparent affinity to cGMP and the Hill coefficient. The degree of functional coupling of intracellular regions in the activation gating was determined by thermodynamic double-mutant cycle analysis. We observed that all four intracellular regions, including the relatively short S4-S5 linker, are involved in controlling the apparent affinity of the channel to cGMP and, moreover, in determining the degree of cooperativity between the subunits, as derived from the Hill coefficient. The interaction energies reveal an interaction of the S4-S5 linker with both the N-terminus and the C-linker, but no interaction with the CNBD.

  16. Photoinduced phenomena in amorphous As4S3Se3-Sn films

    NASA Astrophysics Data System (ADS)

    Iaseniuc, O. V.; Cojocaru, I. A.; Prisacar, A. M.; Nastas, A. M.; Iovu, M. S.

    2016-07-01

    We investigate the kinetics of photodarkening and recording of holographic diffraction gratings in amorphous As4S3Se3 thin-film structures doped with tin (Sn) in concentrations of 0-10 at %. It is established that an increase in the Sn concentration leads to a decrease in the photodarkening rate and degree. The photodarkening kinetics is approximated by a stretched exponential function. It is found that an increase in the Sn concentration leads to a decrease in the transmission (photodarkening) variation in the investigated As4S3Se3-Sn films. It is determined that, in the recording of holographic diffraction gratings at a Sn concentration of 3-8 at %, the As4S3Se3-Sn films exhibit the maximum sensitivity and diffraction efficiency of the recorded gratings. It is shown that the dependence of diffraction efficiency on the As4S3Se3 film thickness has the maximum at a film thickness of 4 µm.

  17. Giant pedunculated hepatocellular carcinoma with hemangioma mimicking intestinal obstruction

    PubMed Central

    2011-01-01

    Background Pedunculated hepatocellular carcinoma (P-HCC) has rarely been reported and is characteristically large and encapsulated. Only sporadic cases have been published, in which P-HCC was combined with other liver tumors (mostly benign), making the diagnosis difficult. Case presentation We report a patient who was admitted to our hospital with clinical features of intestinal obstruction and a palpable mass in the right iliac fossa. Ultrasound, computed tomography and magnetic resonance imaging demonstrated an encapsulated mass of unclear origin and characteristics of liver hemangioma. Laboratory tests revealed elevated α-fetoprotein (> 800 ng/ml) and cancer antigen 125 (> 51.2 U/ml). With a possible diagnosis of giant liver hemangioma, we proceeded to surgery. During surgery, a giant pedunculated tumor was discovered on the inferior surface of the right lobe of the liver, hanging free in the right abdominal cavity towards the right iliac fossa. The macroscopic appearance of the tumor was compatible with liver hemangioma. Tumor resection was performed at a safe distance, including the pedicle. The rest of the liver appeared normal. Histopathological examination revealed grade II and III HCC (according to Edmondson-Steiner's classification) with nodular configuration, central necrosis, and infiltration of the capsule. Underneath the tumor capsule, residual tissue of a cavernous hemangioma was recognized. The resection margins were free of neoplastic tissue. Conclusion This rare presentation of a giant P-HCC combined with a hemangioma with features of intestinal obstruction confirmed the diagnostic difficulties of similar cases, and required prompt surgical treatment. Therefore, patients benefit from surgical resection because both the capsule and the pedicle prevent vascular invasion, therefore improving prognosis. PMID:21939543

  18. THE ORBITAL EVOLUTION OF GAS GIANT PLANETS AROUND GIANT STARS

    SciTech Connect

    Villaver, Eva; Livio, Mario E-mail: mlivio@stsci.ed

    2009-11-01

    Recent surveys have revealed a lack of close-in planets around evolved stars more massive than 1.2 M{sub sun}. Such planets are common around solar-mass stars. We have calculated the orbital evolution of planets around stars with a range of initial masses, and have shown how planetary orbits are affected by the evolution of the stars all the way to the tip of the red giant branch. We find that tidal interaction can lead to the engulfment of close-in planets by evolved stars. The engulfment is more efficient for more-massive planets and less-massive stars. These results may explain the observed semimajor axis distribution of planets around evolved stars with masses larger than 1.5 M{sub sun}. Our results also suggest that massive planets may form more efficiently around intermediate-mass stars.

  19. Resonant Removal of Exomoons during Planetary Migration

    NASA Astrophysics Data System (ADS)

    Spalding, Christopher; Batygin, Konstantin; Adams, Fred C.

    2016-01-01

    Jupiter and Saturn play host to an impressive array of satellites, making it reasonable to suspect that similar systems of moons might exist around giant extrasolar planets. Furthermore, a significant population of such planets is known to reside at distances of several Astronomical Units (AU), leading to speculation that some moons thereof might support liquid water on their surfaces. However, giant planets are thought to undergo inward migration within their natal protoplanetary disks, suggesting that gas giants currently occupying their host star’s habitable zone formed farther out. Here we show that when a moon-hosting planet undergoes inward migration, dynamical interactions may naturally destroy the moon through capture into a so-called evection resonance. Within this resonance, the lunar orbit’s eccentricity grows until the moon eventually collides with the planet. Our work suggests that moons orbiting within about ∼10 planetary radii are susceptible to this mechanism, with the exact number dependent on the planetary mass, oblateness, and physical size. Whether moons survive or not is critically related to where the planet began its inward migration, as well as the character of interlunar perturbations. For example, a Jupiter-like planet currently residing at 1 AU could lose moons if it formed beyond ∼5 AU. Cumulatively, we suggest that an observational census of exomoons could potentially inform us on the extent of inward planetary migration, for which no reliable observational proxy currently exists.

  20. Statistical Study of the Early Solar System's Instability with Four, Five, and Six Giant Planets

    NASA Astrophysics Data System (ADS)

    Nesvorný, David; Morbidelli, Alessandro

    2012-10-01

    Several properties of the solar system, including the wide radial spacing and orbital eccentricities of giant planets, can be explained if the early solar system evolved through a dynamical instability followed by migration of planets in the planetesimal disk. Here we report the results of a statistical study, in which we performed nearly 104 numerical simulations of planetary instability starting from hundreds of different initial conditions. We found that the dynamical evolution is typically too violent, if Jupiter and Saturn start in the 3:2 resonance, leading to ejection of at least one ice giant from the solar system. Planet ejection can be avoided if the mass of the transplanetary disk of planetesimals was large (M disk >~ 50 M Earth), but we found that a massive disk would lead to excessive dynamical damping (e.g., final e 55 <~ 0.01 compared to present e 55 = 0.044, where e 55 is the amplitude of the fifth eccentric mode in the Jupiter's orbit), and to smooth migration that violates constraints from the survival of the terrestrial planets. Better results were obtained when the solar system was assumed to have five giant planets initially, and one ice giant, with mass comparable to that of Uranus and Neptune, was ejected into interstellar space by Jupiter. The best results were obtained when the ejected planet was placed into the external 3:2 or 4:3 resonance with Saturn and M disk ~= 20 M Earth. The range of possible outcomes is rather broad in this case, indicating that the present solar system is neither a typical nor expected result for a given initial state, and occurs, in best cases, with only a sime5% probability (as defined by the success criteria described in the main text). The case with six giant planets shows interesting dynamics but does offer significant advantages relative to the five-planet case.

  1. Giant Splenic Artery Pseudoaneurysm: A Case Report and Literature Review.

    PubMed

    Yagmur, Yusuf; Akbulut, Sami; Gumus, Serdar; Demircan, Firat

    2015-07-01

    Splenic artery aneurysms (SAAs) are the third most frequent intra-abdominal aneurysm, following abdominal aorta and iliac artery aneurysms. SAAs are classified according to their involvement of arterial wall layers: true aneurysms involve all 3 layers (intima, media, and adventitia), and pseudoaneurysms involve only one or two. Herein we present a new case of giant pseudo SAA. A 65-year-old female patient with a pancreatic mass and iron deficiency was referred to our clinic for further investigation. Abdominal ultrasonography, contrast-enhanced CT and magnetic resonance imaging showed a lesion resembling a subcapsular hemangioma in the spleen, and aneurysmatic dilation of the splenic artery with a diameter of >5 cm. The large size of the aneurysm and the clinical findings were indications for surgical treatment. The patient underwent en bloc resection of the spleen, distal pancreas, and aneurysmatic segment of the splenic artery. The patient remains complication-free 2 months after the operation. Spontaneous rupture is the most important life-threatening complications of giant SAAs. Therefore, all symptomatic patients with SAA should be treated, as well as asymptomatic patients with lesions ≥2 cm, who are pregnant or fertile, have portal hypertension, or are candidates for liver transplantation. Despite advances in endovascular techniques, conventional abdominal surgery remains the gold standard for treatment. PMID:26595501

  2. The Clinical Approach Toward Giant Cell Tumor of Bone

    PubMed Central

    van der Heijden, Lizz; Dijkstra, P.D. Sander; van de Sande, Michiel A.J.; Kroep, Judith R.; Nout, Remi A.; van Rijswijk, Carla S.P.; Bovée, Judith V.M.G.; Hogendoorn, Pancras C.W.

    2014-01-01

    We provide an overview of imaging, histopathology, genetics, and multidisciplinary treatment of giant cell tumor of bone (GCTB), an intermediate, locally aggressive but rarely metastasizing tumor. Overexpression of receptor activator of nuclear factor κB ligand (RANKL) by mononuclear neoplastic stromal cells promotes recruitment of numerous reactive multinucleated giant cells. Conventional radiographs show a typical eccentric lytic lesion, mostly located in the meta-epiphyseal area of long bones. GCTB may also arise in the axial skeleton and very occasionally in the small bones of hands and feet. Magnetic resonance imaging is necessary to evaluate the extent of GCTB within bone and surrounding soft tissues to plan a surgical approach. Curettage with local adjuvants is the preferred treatment. Recurrence rates after curettage with phenol and polymethylmethacrylate (PMMA; 8%–27%) or cryosurgery and PMMA (0%–20%) are comparable. Resection is indicated when joint salvage is not feasible (e.g., intra-articular fracture with soft tissue component). Denosumab (RANKL inhibitor) blocks and bisphosphonates inhibit GCTB-derived osteoclast resorption. With bisphosphonates, stabilization of local and metastatic disease has been reported, although level of evidence was low. Denosumab has been studied to a larger extent and seems to be effective in facilitating intralesional surgery after therapy. Denosumab was recently registered for unresectable disease. Moderate-dose radiotherapy (40–55 Gy) is restricted to rare cases in which surgery would lead to unacceptable morbidity and RANKL inhibitors are contraindicated or unavailable. PMID:24718514

  3. CHAOTIC DIFFUSION OF RESONANT KUIPER BELT OBJECTS

    SciTech Connect

    Tiscareno, Matthew S.; Malhotra, Renu

    2009-09-15

    We carried out extensive numerical orbit integrations to probe the long-term chaotic dynamics of the two strongest mean-motion resonances of Neptune in the Kuiper Belt, the 3:2 (Plutinos) and 2:1 (Twotinos). Our primary results include a computation of the relative volumes of phase space characterized by large- and small-resonance libration amplitudes, and maps of resonance stability measured by mean chaotic diffusion rate. We find that Neptune's 2:1 resonance has weaker overall long-term stability than the 3:2-only {approx}15% of Twotinos are projected to survive for 4 Gyr, compared to {approx}27% of Plutinos, based on an extrapolation from our 1-Gyr integrations. We find that Pluto has only a modest effect, causing a {approx}4% decrease in the Plutino population that survives to 4 Gyr. Given current observational estimates, and assuming an initial distribution of particles proportional to the local phase-space volume in the resonance, we conclude that the primordial populations of Plutinos and Twotinos formerly made up more than half the population of the classical and resonant Kuiper Belt. We also conclude that Twotinos were originally nearly as numerous as Plutinos; this is consistent with predictions from early models of smooth giant planet migration and resonance sweeping of the Kuiper Belt and provides a useful constraint for more detailed models.

  4. The Giant Metrewave Radio Telescope

    NASA Astrophysics Data System (ADS)

    Nityananda, R.

    2003-05-01

    The Giant Metrewave Radio Telescope (GMRT) of the National Centre of Radio Astrophysics (NCRA) of the Tata Institute of Fundamental Research (TIFR) at Khodad, India, has been operational in the band 0.2 to 2 metres for the last two and a half years. The system characteristics and performance and recent results from the group will be presented. Details of use over the last six months by scientists from other observatories under the GMRT Time Allocation Committee (GTAC) and future plans will be also be reviewed in this paper. Areas which have been studied include observations made in the GMRT band of neutral hydrogen, nearby galaxies, supernova remnants, the Galactic Centre, pulsars, the Sun and others.

  5. Giant tunneling magnetoresistance in silicene

    NASA Astrophysics Data System (ADS)

    Wang, Yu; Lou, Yiyi

    2013-11-01

    We have theoretically studied ballistic electron transport in silicene under the manipulation of a pair of ferromagnetic gate. Transport properties like transmission and conductance have been calculated by the standard transfer matrix method for parallel and antiparallel magnetization configurations. It is demonstrated here that, due to the stray field-induced wave-vector filtering effect, remarkable difference in configuration-dependent transport gives rise to a giant tunneling magnetoresistance. In combination with the peculiar buckled structure of silicene and its electric tunable energy gap, the receiving magnetoresistance can be efficiently modulated by the externally-tunable stray field, electrostatic potential, and staggered sublattice potential, providing some flexible strategies to construct silicene-based nanoelectronic device.

  6. Giant tunneling magnetoresistance in silicene

    SciTech Connect

    Wang, Yu; Lou, Yiyi

    2013-11-14

    We have theoretically studied ballistic electron transport in silicene under the manipulation of a pair of ferromagnetic gate. Transport properties like transmission and conductance have been calculated by the standard transfer matrix method for parallel and antiparallel magnetization configurations. It is demonstrated here that, due to the stray field-induced wave-vector filtering effect, remarkable difference in configuration-dependent transport gives rise to a giant tunneling magnetoresistance. In combination with the peculiar buckled structure of silicene and its electric tunable energy gap, the receiving magnetoresistance can be efficiently modulated by the externally-tunable stray field, electrostatic potential, and staggered sublattice potential, providing some flexible strategies to construct silicene-based nanoelectronic device.

  7. Hierarchical spin-orbital polarization of a giant Rashba system.

    PubMed

    Bawden, Lewis; Riley, Jonathan M; Kim, Choong H; Sankar, Raman; Monkman, Eric J; Shai, Daniel E; Wei, Haofei I; Lochocki, Edward B; Wells, Justin W; Meevasana, Worawat; Kim, Timur K; Hoesch, Moritz; Ohtsubo, Yoshiyuki; Le Fèvre, Patrick; Fennie, Craig J; Shen, Kyle M; Chou, Fangcheng; King, Phil D C

    2015-09-01

    The Rashba effect is one of the most striking manifestations of spin-orbit coupling in solids and provides a cornerstone for the burgeoning field of semiconductor spintronics. It is typically assumed to manifest as a momentum-dependent splitting of a single initially spin-degenerate band into two branches with opposite spin polarization. Combining polarization-dependent and resonant angle-resolved photoemission measurements with density functional theory calculations, we show that the two "spin-split" branches of the model giant Rashba system BiTeI additionally develop disparate orbital textures, each of which is coupled to a distinct spin configuration. This necessitates a reinterpretation of spin splitting in Rashba-like systems and opens new possibilities for controlling spin polarization through the orbital sector. PMID:26601268

  8. Hierarchical spin-orbital polarization of a giant Rashba system

    PubMed Central

    Bawden, Lewis; Riley, Jonathan M.; Kim, Choong H.; Sankar, Raman; Monkman, Eric J.; Shai, Daniel E.; Wei, Haofei I.; Lochocki, Edward B.; Wells, Justin W.; Meevasana, Worawat; Kim, Timur K.; Hoesch, Moritz; Ohtsubo, Yoshiyuki; Le Fèvre, Patrick; Fennie, Craig J.; Shen, Kyle M.; Chou, Fangcheng; King, Phil D. C.

    2015-01-01

    The Rashba effect is one of the most striking manifestations of spin-orbit coupling in solids and provides a cornerstone for the burgeoning field of semiconductor spintronics. It is typically assumed to manifest as a momentum-dependent splitting of a single initially spin-degenerate band into two branches with opposite spin polarization. Combining polarization-dependent and resonant angle-resolved photoemission measurements with density functional theory calculations, we show that the two “spin-split” branches of the model giant Rashba system BiTeI additionally develop disparate orbital textures, each of which is coupled to a distinct spin configuration. This necessitates a reinterpretation of spin splitting in Rashba-like systems and opens new possibilities for controlling spin polarization through the orbital sector. PMID:26601268

  9. The Metallicity of Giant Planets

    NASA Astrophysics Data System (ADS)

    Thorngren, Daniel P.; Fortney, Jonathan

    2015-12-01

    Unique clues about the formation processes of giant planets can be found in their bulk compositions. Transiting planets provide us with bulk density determinations that can then be compared to models of planetary structure and evolution, to deduce planet bulk metallicities. At a given mass, denser planets have a higher mass fraction of metals. However, the unknown hot Jupiter "radius inflation" mechanism leads to under-dense planets that severely biases this work. Here we look at cooler transiting gas giants (Teff < 1000 K), which do not exhibit the radius inflation effect seen in their warmer cousins. We identified 40 such planets between 20 M_Earth and 20 M_Jup from the literature and used evolution models to determine their bulk heavy-element ("metal") mass. Several important trends are apparent. We see that all planets have at least ~10 M_Earth of metals, and that the mass of metal correlates strongly with the total mass of the planet. The heavy-element mass goes as the square root of the total mass. Both findings are consistent with the core accretion model. We also examined the effect of the parent star metallicity [Fe/H], finding that planets around high-metallicity stars are more likely to have large amounts of metal, but the relation appears weaker than previous studies with smaller sample sizes had suggested. We also looked for connections between bulk composition and planetary orbital parameters and stellar parameters, but saw no pattern, which is also an important result. This work can be directly compared to current and future outputs from planet formation models, including population synthesis.

  10. Direct Imaging of Giant Exoplanets

    NASA Astrophysics Data System (ADS)

    Tamura, Motohide

    Since the first detection of exoplanets around a Sun-like star 51 Peg in 1995, their detection and characterization are mainly led by indirect methods such as radial velocity and transit methods. However, recent progresses of observational techniques have finally enabled the direct imaging observations of giant planets of solar-system-scale orbit (with their semi-major axes less than about 50 AU) around A-type stars (e.g., Marois et al. 2008, 2010) and G-type stars (e.g., Kuzuhara et al. 2013). Direct imaging is useful to obtain the physical and atmospheric parameters of exoplanets. In fact not only colors but also a medium-resolution spectroscopy of such planets has been successfully obtained for their atmospheric characterization (Barman et al. 2013). Their masses are typically a few to ~10 Jupiter masses and they orbit at a Saturn- to-Pluto distance. Therefore, like hot-Jupiters and super-Earths they are unlike any solar-system planets, and called wide-orbit giant planets. A recent large search for planets and disk on the Subaru 8.2-m telescope (SEEDS project) has detected a 3-5 Jupiter-masses planet around a Sun-like star GJ 504 (Kuzuhara et al. 2013). It is the coolest planetary companion so far directly imaged and its near-infrared color is “bluer” than that of other directly imaged planets. In this contribution, I will review the recent progresses on direct imaging of exoplanets, highlight the results of the SEEDS project, and discuss the future developments.

  11. Identification of FX in the heliobacterial reaction center as a [4Fe-4S] cluster with an S = 3/2 ground spin state.

    PubMed

    Heinnickel, Mark; Agalarov, Rufat; Svensen, Nina; Krebs, Carsten; Golbeck, John H

    2006-05-30

    Type I homodimeric reaction centers, particularly the class present in heliobacteria, are not well understood. Even though the primary amino acid sequence of PshA in Heliobacillus mobilis has been shown to contain an F(X) binding site, a functional Fe-S cluster has not been detected by EPR spectroscopy. Recently, we reported that PshB, which contains F(A)- and F(B)-like Fe-S clusters, could be removed from the Heliobacterium modesticaldum reaction center (HbRC), resulting in 15 ms lifetime charge recombination between P798(+) and an unidentified electron acceptor [Heinnickel, M., Shen, G., Agalarov, R., and Golbeck, J. H. (2005) Biochemistry 44, 9950-9960]. We report here that when a HbRC core is incubated with sodium dithionite in the presence of light, the 15 ms charge recombination is replaced with a kinetic transient in the sub-microsecond time domain, consistent with the reduction of this electron acceptor. Concomitantly, a broad and intense EPR signal arises around g = 5 along with a minor set of resonances around g = 2 similar to the spectrum of the [4Fe-4S](+) cluster in the Fe protein of Azotobacter vinelandii nitrogenase, which exists in two conformations having S = (3)/(2) and S = (1)/(2) ground spin states. The Mössbauer spectrum in the as-isolated HbRC core shows that all of the Fe is present in the form of a [4Fe-4S](2+) cluster. After reduction with sodium dithionite in the presence of light, approximately 65% of the Fe appears in the form of a [4Fe-4S](+) cluster; the remainder is in the [4Fe-4S](2+) state. Analysis of the non-heme iron content of HbRC cores indicates an antenna size of 21.6 +/- 1.1 BChl g molecules/P798. The evidence indicates that the HbRC contains a [4Fe-4S] cluster identified as F(X) that is coordinated between the PshA homodimer; in contrast to F(X) in other type I reaction centers, this [4Fe-4S] cluster exhibits an S = (3)/(2) ground spin state. PMID:16716087

  12. Studies on the ingestion characteristics of giant freshwater prawn, Chinese prawn and giant tiger prawn

    NASA Astrophysics Data System (ADS)

    Zang, Wei-Ling; Wang, Wei-Dong; Dai, Xi-Lin; Jiang, Min; Zhu, Zheng-Guo; Yang, Ming-Hui; Liu, Xian-Zhong; Xu, Gui-Rong; Ding, Fu-Jiang

    2000-12-01

    The ingestion of giant freshwater prawn, Chinese prawn and giant tiger prawn had continuity and the ingestion high peak occurred at night. Light and temperature had significant effects on the daily ingestion rate (DIR) of giant freshwater prawn Macrobrachium rosenbergii. Red light and blue light favorably induced favorable ingestion. In the adaptive range of temperature, the DIR increased with rising temperature and feeding frequency, but decreased with rising body weight.

  13. Laser Resonator

    NASA Technical Reports Server (NTRS)

    Harper, L. L. (Inventor)

    1983-01-01

    An optical resonator cavity configuration has a unitary mirror with oppositely directed convex and concave reflective surfaces disposed into one fold and concertedly reversing both ends of a beam propagating from a laser rod disposed between two total internal reflection prisms. The optical components are rigidly positioned with perpendicularly crossed virtual rooflines by a compact optical bed. The rooflines of the internal reflection prisms, are arranged perpendicularly to the axis of the laser beam and to the optical axes of the optical resonator components.

  14. Resonance conditions

    NASA Astrophysics Data System (ADS)

    Rebusco, P.

    2005-11-01

    Non-linear parametric resonances occur frequently in nature. Here we summarize how they can be studied by means of perturbative methods. We show in particular how resonances can affect the motion of a test particle orbiting in the vicinity of a compact object. These mathematical toy-models find application in explaining the structure of the observed kHz Quasi-Periodic Oscillations: we show which aspects of the reality naturally enter in the theory, and which one still remain a puzzle.

  15. Stability studies of As4S4 nanosuspension prepared by wet milling in Poloxamer 407.

    PubMed

    Bujňáková, Zdenka; Dutková, Erika; Baláž, Matej; Turianicová, Erika; Baláž, Peter

    2015-01-15

    In this paper the stability of the arsenic sulfide (As4S4) nanosuspension prepared by wet milling in a circulation mill in the environment of copolymer Poloxamer 407 was studied. The obtained As4S4 particles in nanosuspension were of ∼ 100 nm in size. The influence of temperature and UV irradiation on the changes in physical and/or chemical properties was followed. Long-term stability was observed via particle size distribution and zeta potential measurements. Influence of UV irradiation was studied via UV-vis spectroscopy (UV-vis), photoluminicsence (PL) technique and Fourier transform infrared spectroscopy (FTIR) measurements. The best stability of the nanosuspension (24 weeks) was achieved when stored at 4°C and in the dark. PMID:25448581

  16. Multiferroicity and skyrmions carrying electric polarization in GaV4S8

    PubMed Central

    Ruff, Eugen; Widmann, Sebastian; Lunkenheimer, Peter; Tsurkan, Vladimir; Bordács, Sandor; Kézsmárki, Istvan; Loidl, Alois

    2015-01-01

    Skyrmions are whirl-like topological spin objects with high potential for future magnetic data storage. A fundamental question that is relevant to both basic research and application is whether ferroelectric (FE) polarization can be associated with skyrmions’ magnetic texture and whether these objects can be manipulated by electric fields. We study the interplay between magnetism and electric polarization in the lacunar spinel GaV4S8, which undergoes a structural transition associated with orbital ordering at 44 K and reveals a complex magnetic phase diagram below 13 K, including ferromagnetic, cycloidal, and Néel-type skyrmion lattice (SkL) phases. We found that the orbitally ordered phase of GaV4S8 is FE with a sizable polarization of ~1 μC/cm2. Moreover, we observed spin-driven excess polarizations in all magnetic phases; hence, GaV4S8 hosts three different multiferroic phases with coexisting polar and magnetic order. These include the SkL phase, where we predict a strong spatial modulation of FE polarization close to the skyrmion cores. By taking into account the crystal symmetry and spin patterns of the magnetically ordered phases, we identify exchange striction as the main microscopic mechanism behind the spin-driven FE polarization in each multiferroic phase. Because GaV4S8 is unique among known SkL host materials owing to its polar crystal structure and the observed strong magnetoelectric effect, this study is an important step toward the nondissipative electric field control of skyrmions. PMID:26702441

  17. Juno and Cassini Proximal: Giant Steps Towards Understanding Giant Planets

    NASA Astrophysics Data System (ADS)

    Stevenson, D. J.

    2014-12-01

    In 2016-17, Juno and Cassini Proximal will provide comparable large advances in our understanding of the interiors of Jupiter and Saturn. Both will provide high accuracy gravity and magnetic field data, while Juno will in addition determine the water abundance deep in the Jovian atmosphere, essential for understanding of giant planet formation and the density of the outer envelope (needed to construct interior models). Although Jupiter and Saturn are both gas giants, they differ in important ways (magnetic field, strength of zonal flows, enrichment in heavy elements, and probably the distribution of helium within). The opportunity to contrast and compare will be invaluable. Juno and Cassini are expected to determine the gravity field to about a part in 109 though with different spatial coverage and with less accurate determination near the poles. The determination of Jupiter's likely central concentration of heavy elements is particularly challenging because it is only a few percent at most of the total mass and yet important for understanding Jupiter's formation, which in turn likely determined the architecture of our solar system. This determination will be done from gravity, water determination and magnetic field and also aided by advances in our understanding of material properties. The corresponding determination for Saturn may prove easier (because the heavy element enrichment is a larger fraction of the mass) though complicated by lack of knowledge of water abundance and the need to identify a more precise value for the deep rotation of the planet (difficult for Saturn because of the lack of a measurable magnetic dipole tilt thus far). For both planets, the higher harmonics of gravity will likely be controlled by differential rotation (the zonal flows) and this will tell us their depth, an issue of major interest in the dynamics of these bodies. The magnetic field structure for Jupiter will be determined to higher accuracy than the Earth's core field (since

  18. Resonance behavior of atomic and molecular photoionization amplitudes

    SciTech Connect

    Cherepkov, N. A.; Kuznetsov, V. V.; Semenov, S. K.

    2007-07-15

    The behavior of the partial photoionization amplitudes with a given orbital angular momentum l in the complex plane in resonances is studied. In the autoionization resonances the trajectory of the amplitude in the complex plane corresponds to a circle. With increasing photoelectron energy the amplitude moves about a circle in the counterclockwise direction. The new expressions for the partial amplitudes in the resonance are proposed which are similar to the Fano form but contain the 'partial' profile parameters which are connected with the Fano parameter q by a simple relation. In the giant dipole resonances the amplitudes in the complex plane also move about a circle in the counterclockwise direction provided the Coulomb phase is excluded from the amplitude. In the correlational resonances created by channel interactions with the giant dipole resonance the trajectories of the amplitudes acquire a loop about which the amplitudes move in the counterclockwise direction. Very similar behavior of partial photoionization amplitudes in the complex plane is demonstrated also for the dipole transitions from the K shells of the N{sub 2} molecule in the {sigma}* shape resonance.

  19. Preoperative progressive pneumoperitoneum for giant inguinal hernias.

    PubMed

    Piskin, Turgut; Aydin, Cemalettin; Barut, Bora; Dirican, Abuzer; Kayaalp, Cuneyt

    2010-01-01

    Reduction of giant hernia contents into the abdominal cavity may cause intraoperative and postoperative problems such as abdominal compartment syndrome. Preoperative progressive pneumoperitoneum expands the abdominal cavity, increases the patient's tolerability to operation, and can diminish intraoperative and postoperative complications. Preoperative progressive pneumoperitoneum is recommended for giant ventral hernias, but rarely for giant inguinal hernias. We present two giant inguinal hernia patients who were prepared for hernia repair with preoperative progressive pneumoperitoneum and then treated successfully by graft hernioplasty. We observed that abdominal expansion correlated with the inflated volume and pressure during the first four days of pneumperitoneum. Although insufflated gas volume can be different among patients, we observed that the duration of insufflation may be the same for similar patients.

  20. Giant Omphalocele in an Adolescent Boy.

    PubMed

    Akhtar, Tanveer; Alladi, Anand; Siddappa, O S

    2015-04-01

    Omphalocele is a congenital abdominal wall defect that permits herniation of abdominal viscera into the umbilical cord. We here report a case of a giant omphalocele in an adolescent boy that has not been reported at this age before.

  1. Selecting M-giants with WISE photometry

    NASA Astrophysics Data System (ADS)

    Li, Jing

    2015-08-01

    We use M-giants, M-dwarfs and QSOs identified by LAMOST to assess how well WISE & 2MASS colour-cuts can separate these populations through photometry. We find that the WISE bands are very efficient to separate M-giants from M-dwarfs, especially for the early-type stars. We derive a new photometric relation to estimate [Fe/H] for M-giants. We show that previous photometric distance relations may be biased and devise a new empirical distance relation. We detect M-giants in the Sagittarius stream from the ALLWISE Source Archive. Our detection shows good agreement with the bright stream, although the leading tail appears to be misaligned by a couple of degrees. We have measured the metallicity distribution at four locations along the stream, finding a clear metallicity offset between the leading and trailing tails.

  2. Innate predator recognition in giant pandas.

    PubMed

    Du, Yiping; Huang, Yan; Zhang, Hemin; Li, Desheng; Yang, Bo; Wei, Ming; Zhou, Yingmin; Liu, Yang

    2012-02-01

    Innate predator recognition confers a survival advantage to prey animals. We investigate whether giant pandas exhibit innate predator recognition. We analyzed behavioral responses of 56 naive adult captive giant pandas (Ailuropoda melanoleuca), to urine from predators and non-predators and water control. Giant pandas performed more chemosensory investigation and displayed flehmen behaviors more frequently in response to predator urine compared to both non-predator urine and water control. Subjects also displayed certain defensive behaviors, as indicated by vigilance, and in certain cases, fleeing behaviors. Our results suggest that there is an innate component to predator recognition in captive giant pandas, although such recognition was only slight to moderate. These results have implications that may be applicable to the conservation and reintroduction of this endangered species. PMID:22303845

  3. Giant prostatic fossa with misleading radiographic features.

    PubMed

    Stenzl, A; Fuchs, G J

    1989-01-01

    The long-term complication of a perforation of the prostatic capsule during transurethral resection of the prostate is described. Calcifications in a giant prostatic fossa led to initially misleading radiologic findings.

  4. Bilateral giant abdominoscrotal hydroceles in childhood.

    PubMed

    Serels, S; Kogan, S

    1996-05-01

    There is a paucity of cases in the literature describing the abdominoscrotal hydrocele (ASH). We report the diagnostic and therapeutic aspects of a rapidly expanding giant bilateral ASH in a 4-month-old boy.

  5. Tests of the Giant Impact Hypothesis

    NASA Technical Reports Server (NTRS)

    Jones, J. H.

    1998-01-01

    The giant impact hypothesis has gained popularity as a means of explaining a volatile-depleted Moon that still has a chemical affinity to the Earth. As Taylor's Axiom decrees, the best models of lunar origin are testable, but this is difficult with the giant impact model. The energy associated with the impact would be sufficient to totally melt and partially vaporize the Earth. And this means that there should he no geological vestige of Barber times. Accordingly, it is important to devise tests that may be used to evaluate the giant impact hypothesis. Three such tests are discussed here. None of these is supportive of the giant impact model, but neither do they disprove it.

  6. Innate predator recognition in giant pandas.

    PubMed

    Du, Yiping; Huang, Yan; Zhang, Hemin; Li, Desheng; Yang, Bo; Wei, Ming; Zhou, Yingmin; Liu, Yang

    2012-02-01

    Innate predator recognition confers a survival advantage to prey animals. We investigate whether giant pandas exhibit innate predator recognition. We analyzed behavioral responses of 56 naive adult captive giant pandas (Ailuropoda melanoleuca), to urine from predators and non-predators and water control. Giant pandas performed more chemosensory investigation and displayed flehmen behaviors more frequently in response to predator urine compared to both non-predator urine and water control. Subjects also displayed certain defensive behaviors, as indicated by vigilance, and in certain cases, fleeing behaviors. Our results suggest that there is an innate component to predator recognition in captive giant pandas, although such recognition was only slight to moderate. These results have implications that may be applicable to the conservation and reintroduction of this endangered species.

  7. Giant rhinophyma: Excision with coblation assisted surgery.

    PubMed

    Sahin, Caner; Turker, Mesut; Celasun, Bulent

    2014-01-01

    An 83-year-old man presented with an unusually severe case of rhinophyma. Giant rhinopyhma is very rare in literature. The giant lesion was widely excised using sharp surgical incision and coblation assisted surgery. Using direct coblation to the nasal dorsum may cause edema in the surrounding tissue. There was minimal edema in surrounding tissue using this technique. A full thickness-skin graft was applied after excision. Cosmetic and functional postoperative results were satisfactory.

  8. Giant rhinophyma: Excision with coblation assisted surgery

    PubMed Central

    Sahin, Caner; Turker, Mesut; Celasun, Bulent

    2014-01-01

    An 83-year-old man presented with an unusually severe case of rhinophyma. Giant rhinopyhma is very rare in literature. The giant lesion was widely excised using sharp surgical incision and coblation assisted surgery. Using direct coblation to the nasal dorsum may cause edema in the surrounding tissue. There was minimal edema in surrounding tissue using this technique. A full thickness-skin graft was applied after excision. Cosmetic and functional postoperative results were satisfactory. PMID:25593440

  9. Arterial Embolization of Giant Hepatic Hemangiomas

    SciTech Connect

    Giavroglou, Constantinos; Economou, Hippolete; Ioannidis, Ioannis

    2003-02-15

    Hepatic cavernous hemangiomas are usually small and asymptomatic. They are usually discovered incidentally and only a few require treatment. However, giant hemangiomas may cause symptoms,which are indications for treatment. We describe four cases of symptomatic giant hepatic hemangiomas successfully treated with transcatheter arterial embolization, performed with polyvinyl alcohol particles. There were no complications. Follow-up with clinical and imaging examinations showed disappearance of symptoms and decrease in size of lesions.

  10. The cytology of giant solitary trichoepithelioma

    PubMed Central

    Krishnamurthy, Jayashree; Divya, KN

    2010-01-01

    Giant solitary trichoepithelioma (GST) is a rare trichogenic tumor, which may present as a pigmented lesion. An 80-year-old man was diagnosed to have giant solitary trichoepithelioma on fine-needle aspiration cytology. The cytological findings represented the histological features. The recognition of GST is important because of its close resemblance to basal cell carcinoma and other skin adnexal tumors – clinically, cytologically and histologically. PMID:21187885

  11. Autostereogram resonators

    NASA Astrophysics Data System (ADS)

    Leavey, Sean; Rae, Katherine; Murray, Adam; Courtial, Johannes

    2012-09-01

    Autostereograms, or "Magic Eye" pictures, are repeating patterns designed to give the illusion of depth. Here we discuss optical resonators that create light patterns which, when viewed from a suitable position by a monocular observer, are autostereograms of the three-dimensional shape of one of the mirror surfaces.

  12. Formation of Giant Planets and Brown Dwarves

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.

    2003-01-01

    According to the prevailing core instability model, giant planets begin their growth by the accumulation of small solid bodies, as do terrestrial planets. However, unlike terrestrial planets, the growing giant planet cores become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates. Models predict that rocky planets should form in orbit about most stars. It is uncertain whether or not gas giant planet formation is common, because most protoplanetary disks may dissipate before solid planetary cores can grow large enough to gravitationally trap substantial quantities of gas. Ongoing theoretical modeling of accretion of giant planet atmospheres, as well as observations of protoplanetary disks, will help decide this issue. Observations of extrasolar planets around main sequence stars can only provide a lower limit on giant planet formation frequency . This is because after giant planets form, gravitational interactions with material within the protoplanetary disk may cause them to migrat inwards and be lost to the central star. The core instability model can only produce planets greater than a few jovian masses within protoplanetary disks that are more viscous than most such disks are believed to be. Thus, few brown dwarves (objects massive enough to undergo substantial deuterium fusion, estimated to occur above approximately 13 jovian masses) are likely to be formed in this manner. Most brown dwarves, as well as an unknown number of free-floating objects of planetary mass, are probably formed as are stars, by the collapse of extended gas/dust clouds into more compact objects.

  13. NsrR from Streptomyces coelicolor Is a Nitric Oxide-sensing [4Fe-4S] Cluster Protein with a Specialized Regulatory Function*

    PubMed Central

    Crack, Jason C.; Munnoch, John; Dodd, Erin L.; Knowles, Felicity; Al Bassam, Mahmoud M.; Kamali, Saeed; Holland, Ashley A.; Cramer, Stephen P.; Hamilton, Chris J.; Johnson, Michael K.; Thomson, Andrew J.; Hutchings, Matthew I.; Le Brun, Nick E.

    2015-01-01

    The Rrf2 family transcription factor NsrR controls expression of genes in a wide range of bacteria in response to nitric oxide (NO). The precise form of the NO-sensing module of NsrR is the subject of controversy because NsrR proteins containing either [2Fe-2S] or [4Fe-4S] clusters have been observed previously. Optical, Mössbauer, resonance Raman spectroscopies and native mass spectrometry demonstrate that Streptomyces coelicolor NsrR (ScNsrR), previously reported to contain a [2Fe-2S] cluster, can be isolated containing a [4Fe-4S] cluster. ChIP-seq experiments indicated that the ScNsrR regulon is small, consisting of only hmpA1, hmpA2, and nsrR itself. The hmpA genes encode NO-detoxifying flavohemoglobins, indicating that ScNsrR has a specialized regulatory function focused on NO detoxification and is not a global regulator like some NsrR orthologues. EMSAs and DNase I footprinting showed that the [4Fe-4S] form of ScNsrR binds specifically and tightly to an 11-bp inverted repeat sequence in the promoter regions of the identified target genes and that DNA binding is abolished following reaction with NO. Resonance Raman data were consistent with cluster coordination by three Cys residues and one oxygen-containing residue, and analysis of ScNsrR variants suggested that highly conserved Glu-85 may be the fourth ligand. Finally, we demonstrate that some low molecular weight thiols, but importantly not physiologically relevant thiols, such as cysteine and an analogue of mycothiol, bind weakly to the [4Fe-4S] cluster, and exposure of this bound form to O2 results in cluster conversion to the [2Fe-2S] form, which does not bind to DNA. These data help to account for the observation of [2Fe-2S] forms of NsrR. PMID:25771538

  14. Biomass yield comparisons of giant miscanthus, giant reed, and miscane grown under irrigated and rainfed conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The U.S. Department of Energy has initiated efforts to decrease the nation’s dependence on imported oil by developing domestic renewable sources of cellulosic-derived bioenergy. In this study, giant miscanthus (Miscanthus x giganteus), sugarcane (complex hybrid of Saccharum spp.), and giant reed (Ar...

  15. Obscurin: a multitasking muscle giant.

    PubMed

    Kontrogianni-Konstantopoulos, Aikaterini; Bloch, Robert J

    2005-01-01

    Obscurin (approximately 800 kDa) is the third member of a family of giant proteins expressed in vertebrate striated muscle, along with titin (3-3.7 MDa) and nebulin (approximately 800 kDa). Like its predecessors, it is a multidomain protein composed of tandem adhesion modules and signaling domains. Unlike titin and nebulin, which are integral components of sarcomeres, obscurin is concentrated at the peripheries of Z-disks and M-lines, where it is appropriately positioned to communicate with the surrounding myoplasm. This unique distribution allows obscurin to bind small ankyrin 1, an integral component of the sarcoplasmic reticulum (SR) membrane. Obscurin also associates with the contractile apparatus through its binding to titin, sarcomeric myosin and perhaps other proteins of the contractile apparatus. Overexpression of the COOH-terminus of obscurin in primary myotubes has a dramatic and specific effect on the organization of sarcomeric myosin, indicating a role in the organization and regular assembly of A-bands. Given its ability to associate tightly, selectively and periodically with the periphery of the myofibril, its high affinity for an integral membrane protein of the SR and its close association with thick filaments, we speculate that obscurin is ideally suited to play key roles in modulating the organization and assembly of both the myofibril and the SR.

  16. A giant thunderstorm on Saturn.

    PubMed

    Fischer, G; Kurth, W S; Gurnett, D A; Zarka, P; Dyudina, U A; Ingersoll, A P; Ewald, S P; Porco, C C; Wesley, A; Go, C; Delcroix, M

    2011-07-06

    Lightning discharges in Saturn's atmosphere emit radio waves with intensities about 10,000 times stronger than those of their terrestrial counterparts. These radio waves are the characteristic features of lightning from thunderstorms on Saturn, which last for days to months. Convective storms about 2,000 kilometres in size have been observed in recent years at planetocentric latitude 35° south (corresponding to a planetographic latitude of 41° south). Here we report observations of a giant thunderstorm at planetocentric latitude 35° north that reached a latitudinal extension of 10,000 kilometres-comparable in size to a 'Great White Spot'-about three weeks after it started in early December 2010. The visible plume consists of high-altitude clouds that overshoot the outermost ammonia cloud layer owing to strong vertical convection, as is typical for thunderstorms. The flash rates of this storm are about an order of magnitude higher than previous ones, and peak rates larger than ten per second were recorded. This main storm developed an elongated eastward tail with additional but weaker storm cells that wrapped around the whole planet by February 2011. Unlike storms on Earth, the total power of this storm is comparable to Saturn's total emitted power. The appearance of such storms in the northern hemisphere could be related to the change of seasons, given that Saturn experienced vernal equinox in August 2009.

  17. Red Giant Plunging Through Space

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Poster Version

    This image from NASA's Spitzer Space Telescope (left panel) shows the 'bow shock' of a dying star named R Hydrae, or R Hya, in the constellation Hydra.

    Bow shocks are formed where the stellar wind from a star are pushed into a bow shape (illustration, right panel) as the star plunges through the gas and dust between stars. Our own Sun has a bow shock, but prior to this image one had never been observed around this particular class of red giant star.

    R Hya moves through space at approximately 50 kilometers per second. As it does so, it discharges dust and gas into space. Because the star is relatively cool, that ejecta quickly assumes a solid state and collides with the interstellar medium. The resulting dusty nebula is invisible to the naked eye but can be detected using an infrared telescope. This bow shock is 16,295 astronomical units from the star to the apex and 6,188 astronomical units thick (an astronomical unit is the distance between the sun and Earth). The mass of the bow shock is about 400 times the mass of the Earth.

    The false-color Spitzer image shows infrared emissions at 70 microns. Brighter colors represent greater intensities of infrared light at that wavelength. The location of the star itself is drawn onto the picture in the black 'unobserved' region in the center.

  18. A giant thunderstorm on Saturn.

    PubMed

    Fischer, G; Kurth, W S; Gurnett, D A; Zarka, P; Dyudina, U A; Ingersoll, A P; Ewald, S P; Porco, C C; Wesley, A; Go, C; Delcroix, M

    2011-07-01

    Lightning discharges in Saturn's atmosphere emit radio waves with intensities about 10,000 times stronger than those of their terrestrial counterparts. These radio waves are the characteristic features of lightning from thunderstorms on Saturn, which last for days to months. Convective storms about 2,000 kilometres in size have been observed in recent years at planetocentric latitude 35° south (corresponding to a planetographic latitude of 41° south). Here we report observations of a giant thunderstorm at planetocentric latitude 35° north that reached a latitudinal extension of 10,000 kilometres-comparable in size to a 'Great White Spot'-about three weeks after it started in early December 2010. The visible plume consists of high-altitude clouds that overshoot the outermost ammonia cloud layer owing to strong vertical convection, as is typical for thunderstorms. The flash rates of this storm are about an order of magnitude higher than previous ones, and peak rates larger than ten per second were recorded. This main storm developed an elongated eastward tail with additional but weaker storm cells that wrapped around the whole planet by February 2011. Unlike storms on Earth, the total power of this storm is comparable to Saturn's total emitted power. The appearance of such storms in the northern hemisphere could be related to the change of seasons, given that Saturn experienced vernal equinox in August 2009. PMID:21734705

  19. The Giant Planet Satellite Exospheres

    NASA Technical Reports Server (NTRS)

    McGrath, Melissa A.

    2014-01-01

    Exospheres are relatively common in the outer solar system among the moons of the gas giant planets. They span the range from very tenuous, surface-bounded exospheres (e.g., Rhea, Dione) to quite robust exospheres with exobase above the surface (e.g., lo, Triton), and include many intermediate cases (e.g., Europa, Ganymede, Enceladus). The exospheres of these moons exhibit an interesting variety of sources, from surface sputtering, to frost sublimation, to active plumes, and also well illustrate another common characteristic of the outer planet satellite exospheres, namely, that the primary species often exists both as a gas in atmosphere, and a condensate (frost or ice) on the surface. As described by Yelle et al. (1995) for Triton, "The interchange of matter between gas and solid phases on these bodies has profound effects on the physical state of the surface and the structure of the atmosphere." A brief overview of the exospheres of the outer planet satellites will be presented, including an inter-comparison of these satellites exospheres with each other, and with the exospheres of the Moon and Mercury.

  20. Resonant behavior of dielectric objects (electrostatic resonances).

    PubMed

    Fredkin, D R; Mayergoyz, I D

    2003-12-19

    Resonant behavior of dielectric objects occurs at certain frequencies for which the object permittivity is negative and the free-space wavelength is large in comparison with the object dimensions. Unique physical features of these resonances are studied and a novel technique for the calculation of resonance values of permittivity, and hence resonance frequencies, is proposed. Scale invariance of resonance frequencies, unusually strong orthogonality properties of resonance modes, and a two-dimensional phenomenon of "twin" spectra are reported. The paper concludes with brief discussions of optical controllability of these resonances in semiconductor nanoparticles and a plausible, electrostatic resonance based, mechanism for nucleation and formation of ball lightning.

  1. Resonant behavior of dielectric objects (electrostatic resonances).

    PubMed

    Fredkin, D R; Mayergoyz, I D

    2003-12-19

    Resonant behavior of dielectric objects occurs at certain frequencies for which the object permittivity is negative and the free-space wavelength is large in comparison with the object dimensions. Unique physical features of these resonances are studied and a novel technique for the calculation of resonance values of permittivity, and hence resonance frequencies, is proposed. Scale invariance of resonance frequencies, unusually strong orthogonality properties of resonance modes, and a two-dimensional phenomenon of "twin" spectra are reported. The paper concludes with brief discussions of optical controllability of these resonances in semiconductor nanoparticles and a plausible, electrostatic resonance based, mechanism for nucleation and formation of ball lightning. PMID:14754117

  2. Lattice modes and the Jahn-Teller ferroelectric transition of GaV4S8

    NASA Astrophysics Data System (ADS)

    Hlinka, J.; Borodavka, F.; Rafalovskyi, I.; Docekalova, Z.; Pokorny, J.; Gregora, I.; Tsurkan, V.; Nakamura, H.; Mayr, F.; Kuntscher, C. A.; Loidl, A.; Bordács, S.; Szaller, D.; Lee, H.-J.; Lee, J. H.; Kézsmárki, I.

    2016-08-01

    Crystal of GaV4S8 , a multiferroic system hosting a Néel-type skyrmion lattice phase, has been investigated by polarized Raman and IR spectroscopy above and below the ferroelectric phase transition. Counts of the observed IR and Raman-active modes belonging to distinct irreducible representations agree quite well with group-theory predictions. Phonon spectra are assigned and interpreted with the aid of ab initio calculations of the phonon spectra in the ferroelectric phase. Results allow appreciation of phonon frequencies of the modes involved in Jahn-Teller distortion and their contribution to the spontaneous polarization.

  3. Isotope shift and hyperfine splitting of the 4s{yields}5p transition in potassium

    SciTech Connect

    Behrle, Alexandra; Koschorreck, Marco; Koehl, Michael

    2011-05-15

    We have investigated the 4s {sup 2}S{sub 1/2}{yields}5p {sup 2}P{sub 1/2} transition (D{sub 1} line) of the potassium isotopes {sup 39}K, {sup 40}K, and {sup 41}K using Doppler-free laser saturation spectroscopy. Our measurements reveal the hyperfine splitting of the 5p {sup 2}P{sub 1/2} state of {sup 40}K, and we have determined the specific mass shift and the nuclear field shift constants for the blue (405 nm) D{sub 1} line.

  4. Giant elves: Lightning-generated electromagnetic pulses in giant planets.

    NASA Astrophysics Data System (ADS)

    Luque Estepa, Alejandro; Dubrovin, Daria; José Gordillo-Vázquez, Francisco; Ebert, Ute; Parra-Rojas, Francisco Carlos; Yair, Yoav; Price, Colin

    2015-04-01

    We currently have direct optical observations of atmospheric electricity in the two giant gaseous planets of our Solar System [1-5] as well as radio signatures that are possibly generated by lightning from the two icy planets Uranus and Neptune [6,7]. On Earth, the electrical activity of the troposphere is associated with secondary electrical phenomena called Transient Luminous Events (TLEs) that occur in the mesosphere and lower ionosphere. This led some researchers to ask if similar processes may also exist in other planets, focusing first on the quasi-static coupling mechanism [8], which on Earth is responsible for halos and sprites and then including also the induction field, which is negligible in our planet but dominant in Saturn [9]. However, one can show that, according to the best available estimation for lightning parameters, in giant planets such as Saturn and Jupiter the effect of the electromagnetic pulse (EMP) dominates the effect that a lightning discharge has on the lower ionosphere above it. Using a Finite-Differences, Time-Domain (FDTD) solver for the EMP we found [10] that electrically active storms may create a localized but long-lasting layer of enhanced ionization of up to 103 cm-3 free electrons below the ionosphere, thus extending the ionosphere downward. We also estimate that the electromagnetic pulse transports 107 J to 1010 J toward the ionosphere. There emissions of light of up to 108 J would create a transient luminous event analogous to a terrestrial elve. Although these emissions are about 10 times fainter than the emissions coming from the lightning itself, it may be possible to target them for detection by filtering the appropiate wavelengths. [1] Cook, A. F., II, T. C. Duxbury, and G. E. Hunt (1979), First results on Jovian lightning, Nature, 280, 794, doi:10.1038/280794a0. [2] Little, B., C. D. Anger, A. P. Ingersoll, A. R. Vasavada, D. A. Senske, H. H. Breneman, W. J. Borucki, and The Galileo SSI Team (1999), Galileo images of

  5. Detection of Hot Earths by Giant Planet Transit Tming

    NASA Astrophysics Data System (ADS)

    Deming, Drake; Jennings, Donald E.; Sada, Pedro

    2008-08-01

    Many exoplanet systems contain Jupiter-mass planets on close-in orbits. Theories of planetary system formation account for these hot Jupiters as being end states of inward migration. Variants of those theories also predict terrestrial planets to be captured in mean motion resonance with the hot Jupiters. A recent explosion of discoveries by transit surveys have given us a sample of 25 hot Jupiters transiting stars brighter than V=13. A transit timing survey of these systems could detect hot Earths in resonance, via the large (typically 180 second) perturbations they induce on the giant planet transits. The relatively large sample now available implies that a transit timing survey is well matched to classical observing and telescope scheduling. We propose exploratory observations to perform transit photometry using the 2.1-meter/FLAMINGOS instrument in the J-band, where stellar limb darkening is minimal and transit photometry has maximum sensitivity to shifts in transit time. If our exploratory observations confirm timing precision approaching the predicted values (about 10 seconds for a typical system), we will propose additional observations in later semesters to establish a timing survey.

  6. Evidence for an essential histidine residue in 4S-limonene synthase and other terpene cyclases.

    PubMed

    Rajaonarivony, J I; Gershenzon, J; Miyazaki, J; Croteau, R

    1992-11-15

    (4S)-Limonene synthase, isolated from glandular trichome secretory cell preparations of Mentha x piperita (peppermint) leaves, catalyzes the metal ion-dependent cyclization of geranyl pyrophosphate, via 3S-linalyl pyrophosphate, to (-)-(4S)-limonene as the principal product. Treatment of this terpene cyclase with the histidine-directed reagent diethyl pyrocarbonate at a concentration of 0.25 mM resulted in 50% loss of enzyme activity, and this activity could be completely restored by treatment of the preparation with 5 mM hydroxylamine. Inhibition with diethyl pyrocarbonate was distinguished from inhibition with thiol-directed reagents by protection studies with histidine and cysteine carried out at varying pH. Inactivation of the cyclase by dye-sensitized photooxidation in the presence of rose bengal gave further indication of the presence of a readily modified histidine residue. Protection of the enzyme against inhibition with diethyl pyrocarbonate was afforded by the substrate geranyl pyrophosphate in the presence of Mn2+, and by the sulfonium ion analog of the linalyl carbocation intermediate of the reaction in the presence of inorganic pyrophosphate plus Mn2+, suggesting that an essential histidine residue is located at or near the active site. Similar studies on the inhibition of other monoterpene and sesquiterpene cyclases with diethyl pyrocarbonate suggest that a histidine residue (or residues) may play an important role in catalysis by this class of enzymes. PMID:1444454

  7. Bulk superconductivity in novel Bi4O4S3 compound

    NASA Astrophysics Data System (ADS)

    Singh, Shiva; Husain, M.; Patnaik, S.; Awana, V.

    2013-03-01

    We report here synthesis and superconductivity in BiS2 based newly discovered Bi4O4S3 compound. The compound is synthesized through vacuum encapsulation technique and is contaminated with small impurities of Bi2S3 and Bi. The compound is crystallized in tetragonal I4/mmm space group. Bulk superconductivity with superconducting transition temperature (TC) of 4.4 K is confirmed by AC, DC magnetization and resistivity measurements. For further confirmation of intrinsic bulk superconductivity, we have heat treated Bi at same temperature and in similar condition. Bi is crystallized in rhombohedral R-3m space group (impurity phase Bi is also indexed in same space group) and is non-superconducting. This excludes any possibility of impurity driven superconductivity in the Bi4O4S3 compound. Isothermal magnetization (M-H) measurements indicated closed loops with clear signatures of flux pinning and irreversible behavior. The magneto-transport ρ (T , H) measurements showed a resistive broadening and decrease in TC (ρ = 0) to lower temperatures with increasing magnetic field. The extrapolated upper critical field Hc2(0) is around 31 kOe. In the normal state the ρ ~ T2 is not indicated. National Physical Laboratory (CSIR), New Delhi-110012, India

  8. Identification of two [4Fe-4S]-cluster-containing hydro-lyases from Pyrococcus furiosus.

    PubMed

    van Vugt-Lussenburg, Barbara M A; van der Weel, Laura; Hagen, Wilfred R; Hagedoorn, Peter-Leon

    2009-09-01

    The hyperthermophilic archaeon Pyrococcus furiosus is a strict anaerobe. It is therefore not expected to use the oxidative tricarboxylic acid (TCA) cycle for energy transduction. Nonetheless, its genome encodes more putative TCA cycle enzymes than the closely related Pyrococcus horikoshii and Pyrococcus abyssi, including an aconitase (PF0201). Furthermore, a two-subunit fumarase (PF1755 and PF1754) is encoded on the Pyr. furiosus genome. In the present study, these three genes were heterologously overexpressed in Escherichia coli to enable characterization of the enzymes. PF1755 and PF1754 were shown to form a [4Fe-4S]-cluster-containing heterodimeric enzyme, able to catalyse the reversible hydratation of fumarate. The aconitase PF0201 also contained an Fe-S cluster, and catalysed the conversion from citrate to isocitrate. The fumarase belongs to the class of two-subunit, [4Fe-4S]-cluster-containing fumarate hydratases exemplified by MmcBC from Pelotomaculum thermopropionicum; the aconitase belongs to the aconitase A family. Aconitase probably plays a role in amino acid synthesis when the organism grows on carbohydrates. However, the function of the seemingly metabolically isolated fumarase in Pyr. furiosus has yet to be established.

  9. Bottomonium physics at Υ(4S, 5S, 6S) energies with the Belle detector

    NASA Astrophysics Data System (ADS)

    Tamponi, Umberto

    2016-08-01

    The description of quarkonia as pure quark anti-quark bound states has been recently challenged by the observation of charged states in both the charmonium and bottomonium region and large violations of the heavy quark spin symmetry in hadronic transitions. All these effects can be ascribable to non-negligible contributions from the light quark degrees of freedom in the description of both charmonia and bottomonia. We will report the most recent experimental measurements performed by the Belle collaboration in the Y(4S), Y(5S) and Y(6S) regions, including the measurement of the ratio σ[e+e- → bb̅]/σ[e+e- → μ+ μ- ], the search for neutral states near the B0B̅0 threshold, the first observation of the transition ϒ(4S) → ηhb (lP) and the study of the η transitions at the ϒ(5S) energy. The contribution to the study of the structure of these states coming from the measurement of hadronic transitions will be discussed.

  10. Transformation of dinitrosyl iron complexes [(NO)2Fe(SR)2]- (R = Et, Ph) into [4Fe-4S] Clusters [Fe4S4(SPh)4]2-: relevance to the repair of the nitric oxide-modified ferredoxin [4Fe-4S] clusters.

    PubMed

    Tsou, Chih-Chin; Lin, Zong-Sian; Lu, Tsai-Te; Liaw, Wen-Feng

    2008-12-17

    Transformation of dinitrosyl iron complexes (DNICs) [(NO)(2)Fe(SR)(2)](-) (R = Et, Ph) into [4Fe-4S] clusters [Fe(4)S(4)(SPh)(4)](2-) in the presence of [Fe(SPh)(4)](2-/1-) and S-donor species S(8) via the reassembling process ([(NO)(2)Fe(SR)(2)](-) --> [Fe(4)S(3)(NO)(7)](-) (1)/[Fe(4)S(3)(NO)(7)](2-) (2) --> [Fe(4)S(4)(NO)(4)](2-) (3) --> [Fe(4)S(4)(SPh)(4)](2-) (5)) was demonstrated. Reaction of [(NO)(2)Fe(SR)(2)](-) (R = Et, Ph) with S(8) in THF, followed by the addition of HBF(4) into the mixture solution, yielded complex [Fe(4)S(3)(NO)(7)](-) (1). Complex [Fe(4)S(3)(NO)(7)](2-) (2), obtained from reduction of complex 1 by [Na][biphenyl], was converted into complex [Fe(4)S(4)(NO)(4)](2-) (3) along with byproduct [(NO)(2)Fe(SR)(2)](-) via the proposed [Fe(4)S(3)(SPh)(NO)(4)](2-) intermediate upon treating complex 2 with 1.5 equiv of [Fe(SPh)(4)](2-) and the subsequent addition of 1/8 equiv of S(8) in CH(3)CN at ambient temperature. Complex 3 was characterized by IR, UV-vis, and single-crystal X-ray diffraction. Upon addition of complex 3 to the CH(3)CN solution of [Fe(SPh)(4)](-) in a 1:2 molar ratio at ambient temperature, the rapid NO radical-thiyl radical exchange reaction between complex 3 and the biomimetic oxidized form of rubredoxin [Fe(SPh)(4)](-) occurred, leading to the simultaneous formation of [4Fe-4S] cluster [Fe(4)S(4)(SPh)(4)](2-) (5) and DNIC [(NO)(2)Fe(SPh)(2)](-). This result demonstrates a successful biomimetic reassembly of [4Fe-4S] cluster [Fe(4)S(4)(SPh)(4)](2-) from NO-modified [Fe-S] clusters, relevant to the repair of DNICs derived from nitrosylation of [4Fe-4S] clusters of endonuclease III back to [4Fe-4S] clusters upon addition of ferrous ion, cysteine, and IscS.

  11. Sunspots and Giant-Cell Convection

    NASA Technical Reports Server (NTRS)

    Moore, Ron L.; Hathaway, David H.; Reichmann, Ed J.

    2000-01-01

    From analysis of Doppler velocity images from SOHO/MDI, Hathaway et al (2000, Solar Phys., in press) have found clear evidence for giant convection cells that fill the solar surface, have diameters 3 - 10 times that typical of supergranules, and have lifetimes approx. greater than 10 days. Analogous to the superposition of the granular convection on the supergranular convection, the approx. 30,000 km diameter supergranules are superposed on these still larger giant cells. Because the giant cells make up the large-scale end of a continuous power spectrum that peaks at the size scale of supergranules, it appears that the giant cells are made by the same mode of convection as the supergranules. This suggests that the giant cells are similar to supergranules, just longer-lived, larger in diameter, and deeper. Here we point out that the range of lengths of large bipolar sunspot groups is similar to the size range of giant cells. This, along with the long lives (weeks) of large sunspots, suggests that large sunspots sit in long-lived, deep downflows at the corners of giant cells, and that the distance from leader to follower sunspots in large bipolar groups is the distance from one giant-cell corner to the next. By this line of reasoning, an unusually large and strong downdraft might pull in both legs of a rising spot-group magnetic flux loop, resulting in the formation of a delta sunspot. This leads us to suggest that a large, strong giant-cell corner downdraft should be present at the birthplaces of large delta sunspots for some time (days to weeks) before the birth. Thus, early detection of such downdrafts by local helioscismology might provide an early warning for the formation of those active regions (large delta sunspot groups) that produce the Sun's most violent flares and coronal mass ejections. This work is supported by NASA's Office of Space Science through the Solar Physics Branch of its Sun-Earth Connection Program.

  12. Spin-orbit and rotational couplings in radiative association of C({sup 3}P) and N({sup 4}S) atoms

    SciTech Connect

    Antipov, Sergey V.; Gustafsson, Magnus; Nyman, Gunnar

    2011-11-14

    The role of spin-orbit and rotational couplings in radiative association of C({sup 3}P) and N({sup 4}S) atoms is investigated. Couplings among doublet electronic states of the CN radical are considered, giving rise to a 6-state model of the process. The solution of the dynamical problem is based on the L{sup 2} method, where a complex absorbing potential is added to the Hamiltonian operator in order to treat continuum and bound levels in the same manner. Comparison of the energy-dependent rate coefficients calculated with and without spin-orbit and rotational couplings shows that the couplings have a strong effect on the resonance structure and low-energy baseline of the rate coefficient.

  13. The O(3P) and N(4S) density measurement at 225 km by ultraviolet absorption and fluorescence in the Apollo-Soyuz test project

    NASA Technical Reports Server (NTRS)

    Kaufman, F.; Rawling, W. T.; Donahue, T. M.; Anderson, J. G.; Hudson, R. D.

    1976-01-01

    The densities of O(3P) and N(4S) at 225 km were determined during the Apollo Soyuz Test Project by a resonance absorption/fluorescence technique in which OI and NI line radiation produced and collimated on board the Apollo was reflected from the Soyuz back to the Apollo for spectral analysis. The two spacecraft maneuvered so that a range of observation angles of plus or minus 15 deg with respect to the normal to the orbital velocity vector was scanned. The measurements were made at night on two consecutive orbits at spacecraft separations of 150 and 500 m. The resulting relative counting rates as function of observation angle were compared to calculated values to determine the oxygen value. This value agrees with mass spectrometric measurements made under similar conditions. The nitrogen value is in good agreement with other measurements and suggests a smaller diurnal variation than is predicted by present models.

  14. Branching Fraction for B+ -> pi0 l+ nu, Measured in Upsilon (4S) -> BBbar Events Tagged by B- -> D0 l- nubar (X) Decays

    SciTech Connect

    Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; Grauges, E.; Palano, A.; Pappagallo, M.; Pompili, A.; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; Eigen, G.; Ofte, I.; Stugu, B. /Bergen U. /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /Pisa U. /INFN, Pisa /Prairie View A-M /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Stony Brook /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Vanderbilt U. /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U. /Yale U. /Yale U. /Yale U. /Yale U. /Yale U.

    2005-06-29

    We report a preliminary branching fraction of (1.80 {+-} 0.37{sub stat.} {+-} 0.23{sub syst.}) x 10{sup -4} for the charmless exclusive semileptonic B{sup +} {yields} {pi}{sup 0}{ell}{sup +}{nu} decay, where {ell} can be either a muon or an electron. This result is based on data corresponding to an integrated luminosity of 81 fb{sup -1} collected at the {Upsilon}(4S) resonance with the BABAR detector. The analysis uses B{bar B} events that are tagged by a B meson reconstructed in the semileptonic B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}(X) decays, where X can be either a {gamma} or a {pi}{sup 0} from a D* decay.

  15. Giant components in directed multiplex networks

    NASA Astrophysics Data System (ADS)

    Azimi-Tafreshi, N.; Dorogovtsev, S. N.; Mendes, J. F. F.

    2014-11-01

    We describe the complex global structure of giant components in directed multiplex networks that generalizes the well-known bow-tie structure, generic for ordinary directed networks. By definition, a directed multiplex network contains vertices of one type and directed edges of m different types. In directed multiplex networks, we distinguish a set of different giant components based on the existence of directed paths of different types between their vertices such that for each type of edges, the paths run entirely through only edges of that type. If, in particular, m =2 , we define a strongly viable component as a set of vertices in which for each type of edges each two vertices are interconnected by at least two directed paths in both directions, running through the edges of only this type. We show that in this case, a directed multiplex network contains in total nine different giant components including the strongly viable component. In general, the total number of giant components is 3m. For uncorrelated directed multiplex networks, we obtain exactly the size and the emergence point of the strongly viable component and estimate the sizes of other giant components.

  16. An MHD model for magnetar giant flares

    SciTech Connect

    Meng, Y.; Lin, J.; Zhang, Q. S.; Zhang, L.; Reeves, K. K.; Yuan, F. E-mail: jlin@ynao.ac.cn

    2014-04-10

    Giant flares on soft gamma-ray repeaters that are thought to take place on magnetars release enormous energy in a short time interval. Their power can be explained by catastrophic instabilities occurring in the magnetic field configuration and the subsequent magnetic reconnection. By analogy with the coronal mass ejection events on the Sun, we develop a theoretical model via an analytic approach for magnetar giant flares. In this model, the rotation and/or displacement of the crust causes the field to twist and deform, leading to flux rope formation in the magnetosphere and energy accumulation in the related configuration. When the energy and helicity stored in the configuration reach a threshold, the system loses its equilibrium, the flux rope is ejected outward in a catastrophic way, and magnetic reconnection helps the catastrophe develop to a plausible eruption. By taking SGR 1806–20 as an example, we calculate the free magnetic energy released in such an eruptive process and find that it is more than 10{sup 47} erg, which is enough to power a giant flare. The released free magnetic energy is converted into radiative energy, kinetic energy, and gravitational energy of the flux rope. We calculated the light curves of the eruptive processes for the giant flares of SGR 1806–20, SGR 0526–66, and SGR 1900+14, and compared them with the observational data. The calculated light curves are in good agreement with the observed light curves of giant flares.

  17. Giant Cell Arteritis and Mortality

    PubMed Central

    Crow, R. Wade; Warner, Judith E. A.; Alder, Stephen C.; Zhang, Kang; Schulman, Susan; Digre, Kathleen B.

    2009-01-01

    Background Giant cell arteritis (GCA) is a systemic vasculitis of elderly individuals associated with significant morbidity, including blindness, stroke, and myocardial infarction. Previous studies have investigated whether GCA is associated with increased mortality, with conflicting results. The objective of this study is to determine whether GCA, is associated with increased mortality. Methods Forty-four cases with GCA were identified from the University of Utah Health Sciences Center, the major tertiary care center for the Intermountain West. The Utah Population Database, a unique biomedical information resource, selected cases and age- and gender-matched controls. Cases were defined as patients with a temporal artery biopsy-proven diagnosis of GCA (international classification of diseases [ICD]-9 code 446.5) between 1991 and 2005. Exclusion criteria included a negative biopsy, alternative diagnoses, or insufficient clinical data. For each of the 44 cases, 100 controls were identified; thus, 4,400 controls were included in the data analysis. Median survival time and 5-year cumulative survival were measured for cases and controls. Results The median survival time for the 44 GCA cases was 1,357 days (3.71 years) after diagnosis compared with 3,044 days (8.34 years) for the 4,400 controls (p = 0.04). Five-year cumulative survival was 67% for the control group versus 35% for the cases (p < .001). Survival rates for cases and controls converged at approximately 11.12 years. Conclusions Patients with GCA were more likely than age- and gender-matched controls to die within the first 5 years following diagnosis. PMID:19196636

  18. Anaplastic giant cell thyroid carcinoma.

    PubMed

    Wallin, G; Lundell, G; Tennvall, J

    2004-01-01

    Anaplastic (giant cell) thyroid carcinoma (ATC), is one of the most aggressive malignancies in humans with a median survival time after diagnosis of 3-6 months. Death from ATC was earlier seen because of local growth and suffocation. ATC is uncommon, accounting for less than 5 % of all thyroid carcinomas. The diagnosis can be established by means of multiple fine needle aspiration biopsies, which are neither harmful nor troublesome for the patient. The cytological diagnosis of this high-grade malignant tumour is usually not difficult for a well trained cytologist. The intention to treat patients with ATC is cure, although only few of them survive. The majority of the patients are older than 60 years and treatment must be influenced by their high age. We have by using a combined modality regimen succeeded in achieving local control in most patients. Every effort should be made to control the primary tumour and thereby improve the quality of remaining life and it is important for patients, relatives and the personnel to know that cure is not impossible. Different treatment combinations have been used since 30 years including radiotherapy, cytostatic drugs and surgery, when feasible. In our latest combined regimen, 22 patients were treated with hyper fractionated radiotherapy 1.6Gy x 2 to a total target dose of 46 Gy given preoperatively, 20 mg doxorubicin was administered intravenously once weekly and surgery was carried out 2-3 weeks after the radiotherapy. 17 of these 22 patients were operated upon and none of these 17 patients got a local recurrence. In the future we are awaiting the development of new therapeutic approaches to this aggressive type of carcinoma. Inhibitors of angiogenesis might be useful. Combretastatin has displayed cytotoxicity against ATC cell lines and has had a positive effect on ATC in a patient. Sodium iodide symporter (NIS) genetherapy is also being currently considered for dedifferentiated thyroid carcinomas with the ultimate aim of

  19. Electrodynamics on extrasolar giant planets

    SciTech Connect

    Koskinen, T. T.; Yelle, R. V.; Lavvas, P.; Cho, J. Y-K.

    2014-11-20

    Strong ionization on close-in extrasolar giant planets (EGPs) suggests that their atmospheres may be affected by ion drag and resistive heating arising from wind-driven electrodynamics. Recent models of ion drag on these planets, however, are based on thermal ionization only and do not include the upper atmosphere above the 1 mbar level. These models are also based on simplified equations of resistive magnetohydrodynamics that are not always valid in extrasolar planet atmospheres. We show that photoionization dominates over thermal ionization over much of the dayside atmosphere above the 100 mbar level, creating an upper ionosphere dominated by ionization of H and He and a lower ionosphere dominated by ionization of metals such as Na, K, and Mg. The resulting dayside electron densities on close-in exoplanets are higher than those encountered in any planetary ionosphere of the solar system, and the conductivities are comparable to the chromosphere of the Sun. Based on these results and assumed magnetic fields, we constrain the conductivity regimes on close-in EGPs and use a generalized Ohm's law to study the basic effects of electrodynamics in their atmospheres. We find that ion drag is important above the 10 mbar level where it can also significantly alter the energy balance through resistive heating. Due to frequent collisions of the electrons and ions with the neutral atmosphere, however, ion drag is largely negligible in the lower atmosphere below the 10 mbar level for a reasonable range of planetary magnetic moments. We find that the atmospheric conductivity decreases by several orders of magnitude in the night side of tidally locked planets, leading to a potentially interesting large-scale dichotomy in electrodynamics between the day and night sides. A combined approach that relies on UV observations of the upper atmosphere, phase curve and Doppler measurements of global dynamics, and visual transit observations to probe the alkali metals can potentially be

  20. EXCISION OF GIANT CELL TUMOR OF TENDON SHEATH WITH BONE INVOLVEMENT BY MEANS OF DOUBLE ACCESS APPROACH: CASE REPORT

    PubMed Central

    Alves, Marcelo de Pinho Teixeira

    2015-01-01

    Giant cell tumors of the tendon sheath are common lesions and are the second most frequent tumors in the hand, after synovial cysts. They are diagnosed by means of clinical examination and complementary examinations (simple radiography and magnetic resonance). Erosion and invasion of the phalangeal bone affected may be seen on radiological examination. Magnetic resonance may show a “fluorescent or radiant effect” may be observed, caused by the high quantity of hemosiderin inside the tumor. Surgical treatment is the commonest practice, and complete excision is important for avoiding recurrence of the tumor, especially when bone invasion is observed on imaging examinations, which is generally related to greater tumor recurrence. In this paper, a case of a giant cell tumor of the tendon sheath in the middle phalanx of the third finger of a 45-year-old female patient is presented. This was successfully treated by means of surgery using a double access approach (dorsal and volar). PMID:27026996

  1. NMR solution structure of the N-terminal domain of hERG and its interaction with the S4-S5 linker

    SciTech Connect

    Li, Qingxin; Gayen, Shovanlal; Chen, Angela Shuyi; Huang, Qiwei; Raida, Manfred; Kang, CongBao

    2010-12-03

    Research highlights: {yields} The N-terminal domain (NTD, eag domain) containing 135 residues of hERG was expressed and purified from E. coli cells. {yields} Solution structure of NTD was determined with NMR spectroscopy. {yields} The alpha-helical region (residues 13-23) was demonstrated to possess the characteristics of an amphipathic helix. {yields} NMR titration confirmed the interaction between NTD and the peptide from the S4-S5 linker. -- Abstract: The human Ether-a-go-go Related Gene (hERG) potassium channel mediates the rapid delayed rectifier current (IKr) in the cardiac action potential. Mutations in the 135 amino acid residue N-terminal domain (NTD) cause channel dysfunction or mis-translocation. To study the structure of NTD, it was overexpressed and purified from Escherichia coli cells using affinity purification and gel filtration chromatography. The purified protein behaved as a monomer under purification conditions. Far- and near-UV, circular dichroism (CD) and solution nuclear magnetic resonance (NMR) studies showed that the purified protein was well-folded. The solution structure of NTD was obtained and the N-terminal residues 13-23 forming an amphipathic helix which may be important for the protein-protein or protein-membrane interactions. NMR titration experiment also demonstrated that residues from 88 to 94 in NTD are important for the molecular interaction with the peptide derived from the S4-S5 linker.

  2. If It's Resonance, What is Resonating?

    ERIC Educational Resources Information Center

    Kerber, Robert C.

    2006-01-01

    The phenomenon under the name "resonance," which, is based on the mathematical analogy between mechanical resonance and the behavior of wave functions in quantum mechanical exchange phenomena was described. The resonating system does not have a structure intermediate between those involved in the resonance, but instead a structure which is further…

  3. Direct measurement of the hydrogen-bonding effect on the intrinsic redox potentials of [4Fe-4S] cubane complexes.

    PubMed

    Yang, Xin; Niu, Shuqiang; Ichiye, Toshiko; Wang, Lai-Sheng

    2004-12-01

    To probe how H-bonding effects the redox potential changes in Fe-S proteins, we produced and studied a series of gaseous cubane-type analogue complexes, [Fe(4)S(4)(SEt)(3)(SC(n)H(2n+1))](2-) and [Fe(4)S(4)(SEt)(3)(SC(n)H(2n)OH)](2-) (n = 4, 6, 11; Et = C(2)H(5)). Intrinsic redox potentials for the [Fe(4)S(4)](2+/3+) redox couple involved in these complexes were measured by photoelectron spectroscopy. The oxidation energies from [Fe(4)S(4)(SEt)(3)(SC(n)H(2n)OH)](2-) to [Fe(4)S(4)(SEt)(3)(SC(n)H(2n)OH)](-) were determined directly from the photoelectron spectra to be approximately 130 meV higher than those for the corresponding [Fe(4)S(4)(SEt)(3)(SC(n)H(2n+1))](2-) systems, because of the OH...S hydrogen bond in the former. Preliminary Monte Carlo and density functional calculations showed that the H-bonding takes place between the -OH group and the S on the terminal ligand in [Fe(4)S(4)(SEt)(3)(SC(6)H(12)OH)](2-). The current data provide a direct experimental measure of a net H-bonding effect on the redox potential of [Fe(4)S(4)] clusters without the perturbation of other environmental effects.

  4. 40 CFR 123.35 - As the NPDES Permitting Authority for regulated small MS4s, what is my role?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... regulated small MS4s, what is my role? 123.35 Section 123.35 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS STATE PROGRAM REQUIREMENTS State Program Submissions § 123.35 As the NPDES Permitting Authority for regulated small MS4s, what is my role? (a) You must comply with...

  5. A Giant Sample of Giant Pulses from the Crab Pulsar

    NASA Astrophysics Data System (ADS)

    Mickaliger, M. B.; McLaughlin, M. A.; Lorimer, D. R.; Langston, G. I.; Bilous, A. V.; Kondratiev, V. I.; Lyutikov, M.; Ransom, S. M.; Palliyaguru, N.

    2012-11-01

    We observed the Crab pulsar with the 43 m telescope in Green Bank, WV over a timespan of 15 months. In total we obtained 100 hr of data at 1.2 GHz and seven hours at 330 MHz, resulting in a sample of about 95,000 giant pulses (GPs). This is the largest sample, to date, of GPs from the Crab pulsar taken with the same telescope and backend and analyzed as one data set. We calculated power-law fits to amplitude distributions for main pulse (MP) and interpulse (IP) GPs, resulting in indices in the range of 2.1-3.1 for MP GPs at 1.2 GHz and in the range of 2.5-3.0 and 2.4-3.1 for MP and IP GPs at 330 MHz. We also correlated the GPs at 1.2 GHz with GPs from the Robert C. Byrd Green Bank Telescope (GBT), which were obtained simultaneously at a higher frequency (8.9 GHz) over a span of 26 hr. In total, 7933 GPs from the 43 m telescope at 1.2 GHz and 39,900 GPs from the GBT were recorded during these contemporaneous observations. At 1.2 GHz, 236 (3%) MP GPs and 23 (5%) IP GPs were detected at 8.9 GHz, both with zero chance probability. Another 15 (4%) low-frequency IP GPs were detected within one spin period of high-frequency IP GPs, with a chance probability of 9%. This indicates that the emission processes at high and low radio frequencies are related, despite significant pulse profile shape differences. The 43 m GPs were also correlated with Fermi γ-ray photons to see if increased pair production in the magnetosphere is the mechanism responsible for GP emission. A total of 92,022 GPs and 393 γ-ray photons were used in this correlation analysis. No significant correlations were found between GPs and γ-ray photons. This indicates that increased pair production in the magnetosphere is likely not the dominant cause of GPs. Possible methods of GP production may be increased coherence of synchrotron emission or changes in beaming direction.

  6. A GIANT SAMPLE OF GIANT PULSES FROM THE CRAB PULSAR

    SciTech Connect

    Mickaliger, M. B.; McLaughlin, M. A.; Lorimer, D. R.; Palliyaguru, N.; Langston, G. I.; Bilous, A. V.; Kondratiev, V. I.; Lyutikov, M.; Ransom, S. M.

    2012-11-20

    We observed the Crab pulsar with the 43 m telescope in Green Bank, WV over a timespan of 15 months. In total we obtained 100 hr of data at 1.2 GHz and seven hours at 330 MHz, resulting in a sample of about 95,000 giant pulses (GPs). This is the largest sample, to date, of GPs from the Crab pulsar taken with the same telescope and backend and analyzed as one data set. We calculated power-law fits to amplitude distributions for main pulse (MP) and interpulse (IP) GPs, resulting in indices in the range of 2.1-3.1 for MP GPs at 1.2 GHz and in the range of 2.5-3.0 and 2.4-3.1 for MP and IP GPs at 330 MHz. We also correlated the GPs at 1.2 GHz with GPs from the Robert C. Byrd Green Bank Telescope (GBT), which were obtained simultaneously at a higher frequency (8.9 GHz) over a span of 26 hr. In total, 7933 GPs from the 43 m telescope at 1.2 GHz and 39,900 GPs from the GBT were recorded during these contemporaneous observations. At 1.2 GHz, 236 (3%) MP GPs and 23 (5%) IP GPs were detected at 8.9 GHz, both with zero chance probability. Another 15 (4%) low-frequency IP GPs were detected within one spin period of high-frequency IP GPs, with a chance probability of 9%. This indicates that the emission processes at high and low radio frequencies are related, despite significant pulse profile shape differences. The 43 m GPs were also correlated with Fermi {gamma}-ray photons to see if increased pair production in the magnetosphere is the mechanism responsible for GP emission. A total of 92,022 GPs and 393 {gamma}-ray photons were used in this correlation analysis. No significant correlations were found between GPs and {gamma}-ray photons. This indicates that increased pair production in the magnetosphere is likely not the dominant cause of GPs. Possible methods of GP production may be increased coherence of synchrotron emission or changes in beaming direction.

  7. What Are Polymyalgia Rheumatica and Giant Cell Arteritis?

    MedlinePlus

    ... Cell Arteritis Find a Clinical Trial Journal Articles What Are Polymyalgia Rheumatica and Giant Cell Arteritis? PDF Version Size: 58 KB November 2014 What Are Polymyalgia Rheumatica and Giant Cell Arteritis? Fast ...

  8. Chromospheres of metal-deficient field giants

    NASA Technical Reports Server (NTRS)

    Dupree, A. K.; Hartmann, L.; Smith, Graeme H.

    1990-01-01

    Observations of the 2800-A Mg II line have been obtained with IUE for a sample of 10 metal-deficient field giant stars to search for chromospheric emission and signatures of mass loss, as well as to establish the level of chromospheric radiative energy losses from these stars. Mg II emission is probably present in all stars. High-resolution spectra of three of the brightest giants show asymmetric Mg II profiles which indicate a differentially expanding atmosphere, signaling the presence of outward mass motions. Surprisingly, the stellar surface fluxes in the Mg II lines are commensurate with the values found for disk giant stars (population I) of similar color. In spite of substantially depleted Mg abundances in the target stars (by factors of 10-100 relative to the solar abundance), the radiative losses implied by the Mg II fluxes, and possibly the chromospheric heating mechanism, appear to be reasonably independent of metallicity and age.

  9. Asymptomatic post-rheumatic giant left atrium

    PubMed Central

    Özkartal, Tardu; Tanner, Felix C; Niemann, Markus

    2016-01-01

    A 78-year-old asymptomatic woman was referred to our clinic for a second opinion regarding indication for mitral valve surgery. An echocardiogram showed a moderate mitral stenosis with a concomitant severe regurgitation. The most striking feature, however, was a giant left atrium with a parasternal anteroposterior diameter of 79 mm and a left atrial volume index of 364 mL/m². There are various echocardiographic definitions of a giant left atrium, which are mainly based on measurements of the anteroposterior diameter of the left atrium using M-mode in the parasternal long axis view. Since the commonly accepted method for echocardiographic evaluation of left atrial size is left atrial volume index, we propose a cut-off value of 140 mL/m2 for the definition of a “giant left atrium”. PMID:27354895

  10. Asymptomatic post-rheumatic giant left atrium.

    PubMed

    Özkartal, Tardu; Tanner, Felix C; Niemann, Markus

    2016-06-26

    A 78-year-old asymptomatic woman was referred to our clinic for a second opinion regarding indication for mitral valve surgery. An echocardiogram showed a moderate mitral stenosis with a concomitant severe regurgitation. The most striking feature, however, was a giant left atrium with a parasternal anteroposterior diameter of 79 mm and a left atrial volume index of 364 mL/m². There are various echocardiographic definitions of a giant left atrium, which are mainly based on measurements of the anteroposterior diameter of the left atrium using M-mode in the parasternal long axis view. Since the commonly accepted method for echocardiographic evaluation of left atrial size is left atrial volume index, we propose a cut-off value of 140 mL/m(2) for the definition of a "giant left atrium".

  11. Design, analysis, and modeling of giant magnetostrictive transducers

    NASA Astrophysics Data System (ADS)

    Calkins, Frederick Theodore

    The increased use of giant magnetostrictive, Terfenol-D transducers in a wide variety of applications has led to a need for greater understanding of the materials performance. This dissertation attempts to add to the Terfenol-D transducer body of knowledge by providing an in-depth analysis and modeling of an experimental transducer. A description of the magnetostriction process related to Terfenol-D includes a discussion of material properties, production methods, and the effect of mechanical stress, magnetization, and temperature on the material performance. The understanding of the Terfenol-D material performance provides the basis for an analysis of the performance of a Terfenol-D transducer. Issues related to the design and utilization of the Terfenol-D material in the transducers are considered, including the magnetic circuit, application of mechanical prestress, and tuning of the mechanical resonance. Experimental results from two broadband, Tonpilz design transducers show the effects of operating conditions (prestress, magnetic bias, AC magnetization amplitude, and frequency) on performance. In an effort to understand and utlilize the rich performance space described by the experimental results a variety of models are considered. An overview of models applicable to Terfenol-D and Terfenol-D transducers is provided, including a discussion of modeling criteria. The Jiles-Atherton model of ferromagnetic hysteresis is employed to describe the quasi-static transducer performance. This model requires the estimation of only six physically-based parameters to accurately simulate performance. The model is shown to be robust with respect to model parameters over a range of mechanical prestress, magnetic biases, and AC magnetic field amplitudes, allowing predictive capability within these ranges. An additional model, based on electroacoustics theory, explains trends in the frequency domain and facilitates an analysis of efficiency based on impedance and admittance

  12. Lithium-rich Giants in Globular Clusters

    NASA Astrophysics Data System (ADS)

    Kirby, Evan N.; Guhathakurta, Puragra; Zhang, Andrew J.; Hong, Jerry; Guo, Michelle; Guo, Rachel; Cohen, Judith G.; Cunha, Katia

    2016-03-01

    Although red giants deplete lithium on their surfaces, some giants are Li-rich. Intermediate-mass asymptotic giant branch (AGB) stars can generate Li through the Cameron-Fowler conveyor, but the existence of Li-rich, low-mass red giant branch (RGB) stars is puzzling. Globular clusters are the best sites to examine this phenomenon because it is straightforward to determine membership in the cluster and to identify the evolutionary state of each star. In 72 hours of Keck/DEIMOS exposures in 25 clusters, we found four Li-rich RGB and two Li-rich AGB stars. There were 1696 RGB and 125 AGB stars with measurements or upper limits consistent with normal abundances of Li. Hence, the frequency of Li-richness in globular clusters is (0.2 ± 0.1)% for the RGB, (1.6 ± 1.1)% for the AGB, and (0.3 ± 0.1)% for all giants. Because the Li-rich RGB stars are on the lower RGB, Li self-generation mechanisms proposed to occur at the luminosity function bump or He core flash cannot explain these four lower RGB stars. We propose the following origin for Li enrichment: (1) All luminous giants experience a brief phase of Li enrichment at the He core flash. (2) All post-RGB stars with binary companions on the lower RGB will engage in mass transfer. This scenario predicts that 0.1% of lower RGB stars will appear Li-rich due to mass transfer from a recently Li-enhanced companion. This frequency is at the lower end of our confidence interval. 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.

  13. Electric Dipole Transitions at Magnetoacoustic Resonance

    NASA Astrophysics Data System (ADS)

    Bichurin, M. I.; Petrov, V. M.; Ryabkov, O. V.; Filippov, A. V.; Ivanov, A. A.; Srinivasan, G.

    2006-03-01

    Ferromagnetic-ferroelectric composites show giant magnetoelectric (ME) effects that are facilitated by the sample response to electric, magnetic, and elastic forces. Composites consisting of magnetostrictive ferrites and piezoelectric lead zirconate titanate (PZT) or lead magnesium niobate-lead titanate (PMN-PT) are found to show strong ME coupling. Such materials also provide us with unique opportunities for theoretical and experimental studies on ME coupling when the magnetic and/or electric subsystems show resonance behavior. Two types of resonances are of importance: electromechanical resonance (EMR) for the piezoelectric component and ferromagnetic resonance (FMR) for the magnetic component. At the coincidence of EMR and FMR, i.e., at the magneto-acoustic resonance (MAR) ME interaction becomes stronger [1]. This work focuses on electric dipole transitions in multilayer ferromagnetic-ferroelectric composites, such as yttrium iron garnet (YIG) and PZT, at MAR. Expressions have been obtained for ME susceptibility and the ME coefficient. The results indicate the potential for novel microwave devices based on ME interactions at MAR. Supported by grants from the ARO, ONR and NSF.[1] M.I. Bichurin, V.M. Petrov, O.V. Ryabkov, S.V. Averkin and G. Srinivasan, Phys. Rev. B. 72, 060408(R) (2005).

  14. THE LINE POLARIZATION WITHIN A GIANT Ly{alpha} NEBULA

    SciTech Connect

    Prescott, Moire K. M.; Smith, Paul S.; Schmidt, Gary D.; Dey, Arjun

    2011-04-01

    Recent theoretical work has suggested that Ly{alpha} nebulae could be substantially polarized in the Ly{alpha} emission line, depending on the geometry, kinematics, and powering mechanism at work. Polarization observations can therefore provide a useful constraint on the source of ionization in these systems. In this Letter, we present the first Ly{alpha} polarization measurements for a giant Ly{alpha} nebula at z{approx} 2.656. We do not detect any significant linear polarization of the Ly{alpha} emission: P{sub Ly{alpha}} = 2.6% {+-} 2.8% (corrected for statistical bias) within a single large aperture. The current data also do not show evidence for the radial polarization gradient predicted by some theoretical models. These results rule out singly scattered Ly{alpha} (e.g., from the nearby active galactic nucleus, AGN) and may be inconsistent with some models of backscattering in a spherical outflow. However, the effects of seeing, diminished signal-to-noise ratio, and angle averaging within radial bins make it difficult to put strong constraints on the radial polarization profile. The current constraints may be consistent with higher density outflow models, spherically symmetric infall models, photoionization by star formation within the nebula or the nearby AGN, resonant scattering, or non-spherically symmetric cold accretion (i.e., along filaments). Higher signal-to-noise ratio data probing to higher spatial resolution will allow us to harness the full diagnostic power of polarization observations in distinguishing between theoretical models of giant Ly{alpha} nebulae.

  15. Giant circular dichroism of a molecule in a plasmonic nanoparticle dimer

    NASA Astrophysics Data System (ADS)

    Zhang, Hui; Govorov, A. O.

    2013-03-01

    We report on giant circular dichroism (CD) of a molecule inserted into a plasmonic hot spot. Naturally occurring molecules and biomolecules have typically CD signals in the UV range, whereas plasmonic nanocrystals exhibit strong plasmon resonances in the visible spectral interval. Therefore, excitations of chiral molecules and plasmon resonances are typically off-resonant. Nevertheless, we demonstrate theoretically that it is possible to create strongly-enhanced molecular CD utilizing the plasmons. Specifically, by employing a nanoparticle dimer, we gain simultaneously a strong plasmonic enhancement and a shift of optical CD from the UV range to the visible. The associated mechanism of giant CD comes from the Coulomb interaction which is greatly amplified in a plasmonic hot spot. Two key factors play a role in the described effect: One is the Coulomb interaction within the molecule-dimer complex giving rise to the plasmon peak in the CD spectrum, whereas the other one is the plasmonic enhancement of the absorption process in a chiral molecule. We propose that, by using the hot spot effect and plasmon-induced CD signals, one can design optical sensors to study chirality of biomolecules. This work was supported by Volkswagen Foundation and NSF (project number CBET-0933415).

  16. Superconducting properties of Rh9In4S4 single crystals

    NASA Astrophysics Data System (ADS)

    Kaluarachchi, Udhara S.; Lin, Qisheng; Xie, Weiwei; Taufour, Valentin; Bud'ko, Sergey L.; Miller, Gordon J.; Canfield, Paul C.

    2016-03-01

    The synthesis and crystallographic, thermodynamic, and transport properties of single crystalline Rh9In4S4 were studied. The resistivity, magnetization, and specific heat measurements all clearly indicate bulk superconductivity with a critical temperature, Tc˜ 2.25 K. The Sommerfeld coefficient γ and the Debye temperature (ΘD) were found to be 34 mJ mol-1 K-2 and 217 K, respectively. The observed specific heat jump, Δ C /γ Tc =1.66 , is larger than the expected BCS weak coupling value of 1.43. Ginzburg-Landau (GL) ratio of the low-temperature GL-penetration depth, λGL≈ 5750 Å, to the GL-coherence length, ξGL≈ 94 Å, is large: κ ˜ 60 . Furthermore, we observed a peak effect in the resistivity measurement as a function of both temperature and magnetic field.

  17. Validation of a plant dynamics code for 4S - Test analysis of natural circulation behavior

    SciTech Connect

    Sebe, F.; Horie, H.; Matsumiya, H.; Fanning, T. H.

    2012-07-01

    A plant transient dynamics code for a sodium-cooled fast reactor was developed by Toshiba. The code is used to evaluate the safety performance of Super-Safe, Small, and Simple reactor (4S) for Anticipated Operational Occurrences (AOOs), Design Basis Accident (DBA) and Beyond DBA (BDBA). The code is currently undergoing verification and validation (V and V). As one of the validation, test analysis of the Shutdown Heat Removal Test (SHRT)-17 performed in the Experimental Breeder Reactor (EBR)-II was conducted. The SHRT-17 is protected loss of flow test. The purpose of this validation is to confirm capability of the code to simulate natural circulation behavior of the plant. As a result, good agreements are shown between the analytical results and the measured data which were available from instrumented subassembly. The detailed validation result of the natural circulation behavior is described in this paper. (authors)

  18. Superconducting properties of Rh9In4S4 single crystals

    DOE PAGES

    Kaluarachchi, Udhara S.; Lin, Qisheng; Xie, Weiwei; Taufour, Valentin; Bud'ko, Sergey L.; Miller, Gordon J.; Canfield, Paul C.

    2016-03-28

    The synthesis and crystallographic, thermodynamic, and transport properties of single crystalline Rh9In4S4 were studied. The resistivity, magnetization, and specific heat measurements all clearly indicate bulk superconductivity with a critical temperature, Tc~2.25 K. The Sommerfeld coefficient γ and the Debye temperature (ΘD) were found to be 34 mJ mol–1 K–2 and 217 K, respectively. The observed specific heat jump, ΔC/γTc=1.66, is larger than the expected BCS weak coupling value of 1.43. Ginzburg-Landau (GL) ratio of the low-temperature GL-penetration depth, λGL≈5750 Å, to the GL-coherence length, ξGL≈94 Å, is large: κ ~60. However, we observed a peak effect in the resistivity measurementmore » as a function of both temperature and magnetic field.« less

  19. Asymmetry in the triplet 3p-4s Mg lines in cool DZ white dwarfs

    NASA Astrophysics Data System (ADS)

    Allard, N. F.; Leininger, T.; Gadéa, F. X.; Brousseau-Couture, V.; Dufour, P.

    2016-04-01

    The purpose of the present work is to make an exhaustive study of the line shape of the triplet 3p-4s Mg line (Mgb triplet), which is perturbed by He in the extreme physical conditions found in the cool atmosphere of DZ white dwarfs. This study is undertaken by inferring both a unified theory of spectral line broadening and ab initio potential energies. Cool white dwarfs require a specific treatment for line broadening owing to the high helium densities that are involved. Beyond the conventional symmetrical Lorentzian core at low density, we show that the line profiles are asymmetrical and have significant additional contributions on the short wavelength side. This blue asymmetry is a consequence of low maxima in the corresponding Mg-He potential energy difference curves at short and intermediate internuclear distances. The new profiles are shown to provide a good fit to an SDSS (Sloan Digital Sky Survey) observation.

  20. Collision Induced Dissociation of [4Fe-4S] Cubane Cluster Complexes: [Fe4S4C14-x(SC2H5)x]2-/1- (x=0-4)

    SciTech Connect

    Fu, Youjun; Laskin, Julia; Wang, Lai S.

    2006-09-01

    Collision-induced dissociation (CID) experiments on a series of [4Fe-4S] cluster ions, [Fe4S4Cl4-x(SC2H5)x]2-/1- (x = 0 - 4), revealed that their fragmentation channels change with the coordination environment. Among the three Coulomb repulsion related channels for the doubly charged species, the collision induced electron detachment channel was found to become more significant from x = 0 to 4 due to the decreasing electron binding energies and the magnitude of the repulsion Coulomb barrier, while both the ligand detachment of Cl- and the fission of the [Fe4S4]2+ core became more and more significant with the increase of the Cl- coordination, and eventually became the dominant channel at x = 0. From the parents containing the -SC2H5 ligand, neutral losses of HSC2H5 (62) and/or HSCH=CH2 (60) were observed. It was proposed that inter- and intra-ligand proton transfer could happen during the CID process, resulting in hydrogen coordination to the [4Fe-4S] cluster. In the presence of O2, [Fe4S4Cl3(SC2H5)]2- and [Fe4S4Cl4]2- can form the O2-substituted products [Fe4S4Cl2(SC2H5)O2]- and [Fe4S4Cl3O2]-, respectively. It was shown that the O2 complexation occurs by coordination to the empty iron site of the [4Fe-4S] cubane core after dissociation of one Cl- ligand.

  1. Overcoming Migration during Giant Planet Formation

    NASA Astrophysics Data System (ADS)

    Thommes, Edward W.; Nilsson, Leif; Murray, Norman

    2007-02-01

    In the core accretion model, gas giant formation is a race between growth and migration; for a core to become a Jovian planet, it must accrete its envelope before it spirals into the host star. We use a multizone numerical model to extend our previous investigation of the ``window of opportunity'' for gas giant formation within a disk. When the collision cross section enhancement due to core atmospheres is taken into account, we find that a broad range of protoplanetary disks possess such a window.

  2. Giant Lipoma of Posterior Cervical Region

    PubMed Central

    Kumar, Lovekesh; Karande, Snehal K.; Kolhe, Yuvraj

    2014-01-01

    Lipomas are the slow growing soft tissue tumors of benign nature. They commonly grow on torso and extremities but may also develop in head and neck region. Rarely lipomas can grow to acquire gigantic proportions, turning into an entity termed as giant lipoma. Such lipomas are entitled to immediate attention as they have a relatively high malignant potential. We report a rare case of giant cervical lipoma in an elderly gentleman, followed by a brief discussion on diagnosis and management of the disorder. PMID:25349767

  3. Giant eruptions of very massive stars

    NASA Astrophysics Data System (ADS)

    Davidson, Kris

    2016-07-01

    Giant eruptions or supernova-impostor events are far more mysterious than true supernovae. An extreme example can release as much radiative energy as a SN, ejecting several Mʘ of material. These events involve continuous radiation-driven outflows rather than blast waves. They constitute one of the main unsolved problems in stellar astrophysics, but have received little theoretical attention. The most notorious giant-eruption survivor, ƞ Carinae, is amazingly close to us for such a rare event. It offers a wealth of observational clues, many of them quite unexpected in terms of simple theory.

  4. GIANT PITUITARY ADENOMA WITH NORMAL VISION AND MISLEADING RADIOLOGICAL FINDINGS.

    PubMed

    Khalid, Muhammad; Raina, Umer Farooq; uz Zaman, Khaleeq; Tahir, Muhammad

    2015-01-01

    Giant pituitary adenomas are rare and present with visual loss. Giant pituitary adenoma has rarely been reported presenting with normal vision. We report Giant pituitary adenoma with Normal vision in a 35 years old patient presenting with adult onset epilepsy and headache. PMID:26721053

  5. A Large-scale Relativistic Configuration-interaction Approach: Application to the 4s2 - 4s4p Transition Energies and E1 Rates for Zn-like Ions

    SciTech Connect

    Chen, M H; Cheng, K T

    2009-08-28

    Relativistic configuration-interaction calculations of the 4s4p excitation energies and 4s{sup 2} - 4s4p E1 transitions for Zn-like ions from Z = 30 to 92 are shown. B-spline basis functions are used for these large-scale calculations. QED corrections to the excitation energies are also calculated. Results are in good agreement with other theories and with experiment, and demonstrate the utility of this method for high-precision atomic structure calculations not just for few-electron systems but also for large atomic systems such as Zn-like ions along the entire isoelectronic sequence.

  6. MAPPING DIRECTLY IMAGED GIANT EXOPLANETS

    SciTech Connect

    Kostov, Veselin; Apai, Daniel

    2013-01-01

    With the increasing number of directly imaged giant exoplanets, the current atmosphere models are often not capable of fully explaining the spectra and luminosity of the sources. A particularly challenging component of the atmosphere models is the formation and properties of condensate cloud layers, which fundamentally impact the energetics, opacity, and evolution of the planets. Here we present a suite of techniques that can be used to estimate the level of rotational modulations these planets may show. We propose that the time-resolved observations of such periodic photometric and spectroscopic variations of extrasolar planets due to their rotation can be used as a powerful tool to probe the heterogeneity of their optical surfaces. In this paper, we develop simulations to explore the capabilities of current and next-generation ground- and space-based instruments for this technique. We address and discuss the following questions: (1) what planet properties can be deduced from the light curve and/or spectra, and in particular can we determine rotation periods, spot coverage, spot colors, and spot spectra?; (2) what is the optimal configuration of instrument/wavelength/temporal sampling required for these measurements?; and (3) can principal component analysis be used to invert the light curve and deduce the surface map of the planet? Our simulations describe the expected spectral differences between homogeneous (clear or cloudy) and patchy atmospheres, outline the significance of the dominant absorption features of H{sub 2}O, CH{sub 4}, and CO, and provide a method to distinguish these two types of atmospheres. Assuming surfaces with and without clouds for most currently imaged planets the current models predict the largest variations in the J band. Simulated photometry from current and future instruments is used to estimate the level of detectable photometric variations. We conclude that future instruments will be able to recover not only the rotation periods

  7. Fission and dipole resonances in metal clusters

    SciTech Connect

    Martin, T. P.; Billas, I. M. L.; Branz, W.; Heinebrodt, M.; Tast, F.; Malinowski, N.

    1997-06-20

    It is not obvious that metal clusters should behave like atomic nuclei--but they do. Of course the energy and distance scales are quite different. But aside from this, the properties of these two forms of condensed matter are amazingly similar. The shell model developed by nuclear physicists describes very nicely the electronic properties of alkali metal clusters. The giant dipole resonances in the excitation spectra of nuclei have their analogue in the plasmon resonances of metal clusters. Finally, the droplet model describing the fission of unstable nuclei can be successively applied to the fragmentation of highly charged metal clusters. The similarity between clusters and nuclei is not accidental. Both systems consist of fermions moving, nearly freely, in a confined space.

  8. Secular resonances in circumstellar systems in binary stars

    NASA Astrophysics Data System (ADS)

    Bazso, A.; Pilat-Lohinger, E.; Eggl, S.; Funk, B.; Bancelin, D.

    2016-02-01

    Planet formation around single stars is already a complicated matter, but extrasolar planets are also present in binary and multiple star systems. We investigate circumstellar planets in binary star systems with stellar separations below 100 astronomical units. For a selection of 11 systems with at least one detected giant planet we determine the location and extension of the habitable zone (HZ), subject to the incident stellar flux from both stars. We work out the stability of additional hypothetical terrestrial planets in or close to the HZ in these systems. To study the secular dynamics we apply a semi-analytical method. This method employs a first-order perturbation theory to determine the secular frequencies of objects moving under the gravitational influence of two much more massive perturbers. The other part uses a single numerical integration of the equations of motion and a frequency analysis of the obtained time-series to determine the apsidal precession frequencies of the massive bodies. By combining these two parts we are able to find the location of the most important secular resonances and the regions of chaotic motion. We demonstrate that terrestrial planets interior to the giant planet’s orbit may suffer from a linear secular resonance that could prevent the existence of habitable planets. Contrary to this, close-in giant planets are less of a problem, but one has to take into account the general relativistic precession of the pericenter that can also lead to resonances.

  9. New Insight into the Pygmy Dipole Resonance in Stable Nuclei

    SciTech Connect

    Neumann-Cosel, P. von

    2008-11-11

    Two examples of recent work on the structure of low-energy electric dipole modes are presented. The first part discusses the systematics of the pygmy dipole resonance (PDR) in stable tin isotopes deduced from high-resolution ({gamma},{gamma}') experiments. These help to distinguish between microscopic QRPA calculations based on either a relativistic or a nonrelativistic mean-field description, predicting significantly different properties of the PDR. The second part presents attempts to unravel the structure of dipoles modes at energies below the giant dipole resonance (GDR) in {sup 208}Pb with a high-resolution measurement of the (p-vector,p-vector') reaction under 0 deg.

  10. Giant molecules composed of polar molecules and atoms in mixed dimensions

    NASA Astrophysics Data System (ADS)

    Qi, Ran; Tan, Shina

    2014-05-01

    Two or three polar molecules, confined to one or two dimensions, can form stable bound states with a single atom living in three dimensions, if the molecule and the atom can interact resonantly such that their mixed dimensional scattering length is large. We call these bound states ``giant molecules'' since it's a molecule composed of smaller molecules and atoms. We study their properties using techniques including exact numerical solution, exact qunatum diffusion Monte Carlo (QMC), Born-Oppenheimer approximation (BOA), and semiclassical approximation. These bound states have a hierarchical structure reminiscent of the celestial systems.

  11. Surgical treatment of a giant left ventricular aneurysm- a case report.

    PubMed

    Schaitza, Gustavo Alves; Faria Neto, José Rocha; Francisco, Julio Cesar; Baena, Cristiana Pellegrino; Giffhorn, Helcio; Olandoski, Bruna; Meira, Leanderson Franco de; Guarita-Souza, Luiz César

    2014-01-01

    An aneurysm of the left ventricle is a complication of acute myocardial infarction. We report a case of a giant aneurysm of the left ventricle after myocardial infarction in a 59 year-old male patient. The surgery to correct the aneurysm was performed with the use of cardiopulmonary bypass under normothermia. A bovine pericardial patch was used for the geometric reconstruction of the ventricular wall affected by the aneurysm. After the procedure, echocardiography and magnetic resonance imaging revealed improvement in left ventricular ejection fraction and volume reduction.

  12. Carpal tunnel syndrome caused by a giant cell tumour of the flexor tendon sheath.

    PubMed

    Meek, Marcel F; Sheikh, Zahid A; Quinton, David N

    2014-02-01

    A 76-year-old woman developed right carpal tunnel syndrome after being conservatively treated for tenosynovitis of the flexor tendons with associated mild carpal tunnel syndrome. A magnetic resonance imaging scan showed a tumour in the carpal tunnel. Re-exploration showed that the median nerve was being compressed by a giant cell tumour of the flexor tendon sheaths. Appropriate imaging is advised in patients with additional findings (such as swelling) or in patients with secondary carpal tunnel syndrome and incomplete response to conservative treatment, to exclude a space-occupying lesion.

  13. Giant cross-polarization conversion of terahertz radiation by plasmons in an active graphene metasurface

    NASA Astrophysics Data System (ADS)

    Polischuk, O. V.; Melnikova, V. S.; Popov, V. V.

    2016-09-01

    Results of theoretical investigation of the cross-polarization conversion of terahertz (THz) radiation by the graphene metasurface formed by a periodic array of graphene nanoribbons located at the surface of a high-refractive-index dielectric substrate are presented. Giant polarization conversion at the plasmon resonance frequencies takes place without applying external DC magnetic field. Pumping graphene by its direct optical illumination or diffusion pumping allows for compensating the Drude losses in graphene and leads to further enhancement of the polarization conversion. It is shown that the total polarization conversion can be achieved in the total internal reflection regime of THz wave from the graphene metasurface at room temperature.

  14. Presymptomatic testing for Huntington's disease. A case complicated by recombination within the D4S10 locus.

    PubMed

    Curtis, A; Millan, F; Holloway, S; Mennie, M; Crosbie, A; Raeburn, J A; Brock, D J

    1989-01-01

    Presymptomatic testing for Huntington's disease (HD) is possible through the use of restriction fragment length polymorphisms (RFLPs) at the closely linked D4S10 locus. Recombination between the HD and D4S10 loci will occur in 4%-5% of meioses, and is a well-recognised complication of predictive testing. Recombination between RFLPs within the D4S10 locus is a rare event and can usually be ignored. We report a case where such an intra-locus recombination frustrated attempts to predict the chance of a high-risk individual inheriting the HD gene.

  15. THE REDSHIFT DISTRIBUTION OF GIANT ARCS IN THE SLOAN GIANT ARCS SURVEY

    SciTech Connect

    Bayliss, Matthew B.; Gladders, Michael D.; Koester, Benjamin P.; Oguri, Masamune; Hennawi, Joseph F.; Sharon, Keren; Dahle, Haakon

    2011-01-20

    We measure the redshift distribution of a sample of 28 giant arcs discovered as a part of the Sloan Giant Arcs Survey. Gemini/GMOS-North spectroscopy provides precise redshifts for 24 arcs, and 'redshift desert' constrains for the remaining 4 arcs. This is a direct measurement of the redshift distribution of a uniformly selected sample of bright giant arcs, which is an observable that can be used to inform efforts to predict giant arc statistics. Our primary giant arc sample has a median redshift z = 1.821 and nearly two-thirds of the arcs, 64%, are sources at z {approx}> 1.4, indicating that the population of background sources that are strongly lensed into bright giant arcs resides primarily at high redshift. We also analyze the distribution of redshifts for 19 secondary strongly lensed background sources that are not visually apparent in Sloan Digital Sky Survey imaging, but were identified in deeper follow-up imaging of the lensing cluster fields. Our redshift sample for the secondary sources is not spectroscopically complete, but combining it with our primary giant arc sample suggests that a large fraction of all background galaxies that are strongly lensed by foreground clusters reside at z {approx}> 1.4. Kolmogorov-Smirnov tests indicate that our well-selected, spectroscopically complete primary giant arc redshift sample can be reproduced with a model distribution that is constructed from a combination of results from studies of strong-lensing clusters in numerical simulations and observational constraints on the galaxy luminosity function.

  16. Measurement of the ratio fracl B(Υ(4S)arrow B^+B^-)l B(Υ(4S)arrow B^0 barB^0)

    NASA Astrophysics Data System (ADS)

    Hadavand, Haleh

    2003-04-01

    The ratio R^+/0=fracl B(Υ(4S) arrow B^+B^-)l B(Υ(4S) arrow B^0 barB^0) is measured with fully reconstructed candidates for B^± arrow J/ψ K^± and B^0 arrow J/ψ K^0S decays. Results are based on a data sample collected with the BaBar detector from 1999 to 2002.

  17. Floret-like multinucleated giant cells in neurofibroma

    PubMed Central

    Shaktawat, Sameer Singh; Golka, Dariusz

    2007-01-01

    This short report discusses a case of neurofibroma containing floret-like multinucleated giant cells. This being the second such case in the literature. Floret-like multinucleated giant cells have been reported in gynaecomastia and neurofibroma in neurofibromatosis type 1. These cells have been reported in uncommon soft tissue tumours including pleomorphic lipoma, giant cell collagenoma, giant cell fibroblastoma and giant cell angiofibroma. We recommend these cells to be interpreted carefully keeping in mind the rare malignant change in neurofibromas. Immunohistochemistry would help in defining the nature of such cells. PMID:18067673

  18. Floret-like multinucleated giant cells in neurofibroma.

    PubMed

    Shaktawat, Sameer Singh; Golka, Dariusz

    2007-12-08

    This short report discusses a case of neurofibroma containing floret-like multinucleated giant cells. This being the second such case in the literature. Floret-like multinucleated giant cells have been reported in gynaecomastia and neurofibroma in neurofibromatosis type 1. These cells have been reported in uncommon soft tissue tumours including pleomorphic lipoma, giant cell collagenoma, giant cell fibroblastoma and giant cell angiofibroma. We recommend these cells to be interpreted carefully keeping in mind the rare malignant change in neurofibromas. Immunohistochemistry would help in defining the nature of such cells.

  19. Tuberculosis Detection by Giant African Pouched Rats

    ERIC Educational Resources Information Center

    Poling, Alan; Weetjens, Bart; Cox, Christophe; Beyene, Negussie; Durgin, Amy; Mahoney, Amanda

    2011-01-01

    In recent years, operant discrimination training procedures have been used to teach giant African pouched rats to detect tuberculosis (TB) in human sputum samples. This article summarizes how the rats are trained and used operationally, as well as their performance in studies published to date. Available data suggest that pouched rats, which can…

  20. Giant Viruses of Amoebas: An Update.

    PubMed

    Aherfi, Sarah; Colson, Philippe; La Scola, Bernard; Raoult, Didier

    2016-01-01

    During the 12 past years, five new or putative virus families encompassing several members, namely Mimiviridae, Marseilleviridae, pandoraviruses, faustoviruses, and virophages were described. In addition, Pithovirus sibericum and Mollivirus sibericum represent type strains of putative new giant virus families. All these viruses were isolated using amoebal coculture methods. These giant viruses were linked by phylogenomic analyses to other large DNA viruses. They were then proposed to be classified in a new viral order, the Megavirales, on the basis of their common origin, as shown by a set of ancestral genes encoding key viral functions, a common virion architecture, and shared major biological features including replication inside cytoplasmic factories. Megavirales is increasingly demonstrated to stand in the tree of life aside Bacteria, Archaea, and Eukarya, and the megavirus ancestor is suspected to be as ancient as cellular ancestors. In addition, giant amoebal viruses are visible under a light microscope and display many phenotypic and genomic features not found in other viruses, while they share other characteristics with parasitic microbes. Moreover, these organisms appear to be common inhabitants of our biosphere, and mimiviruses and marseilleviruses were isolated from human samples and associated to diseases. In the present review, we describe the main features and recent findings on these giant amoebal viruses and virophages.

  1. [Habitat selection attributes of giant panda].

    PubMed

    Kang, Dong-Wei; Zhao, Zhi-Jiang; Guo, Wen-Xia; Tan, Liu-Yi; Kang, Wen; Li, Jun-Qing

    2011-02-01

    Based on the 1997-2009 inventory data of Wanglang Nature Reserve, the habitat selection attributes of giant panda were studied from the aspects of topography, forest community structure, and main feeding bamboo by the methods of frequency distribution and Bailey. The giant panda had obvious habitat preferences. Topographically, the preferred microhabitat was on the even or convex slopes at the ridge, top, or middle part of mountain body at an elevation 2500-3000 m, with southwest aspect, 6 degrees-30 degrees, and the distance to the nearest water source > 300 m. As for the forest community structure, the giant panda preferred the microhabitat with the bamboo succeeded from secondary forest or mixed conifer and broad-leaved forest, and with the average tree height being 20-29 m and the shrub coverage being 0-24%. The preferred main feeding bamboo by the giant panda was the growing well Fargesia denudate with an average height of 2-5 m and the coverage of > 50%.

  2. Chirp-driven giant phase space vortices

    NASA Astrophysics Data System (ADS)

    Trivedi, Pallavi; Ganesh, Rajaraman

    2016-06-01

    In a collisionless, unbounded, one-dimensional plasma, modelled using periodic boundary conditions, formation of steady state phase space coherent structures or phase space vortices (PSV) is investigated. Using a high resolution one-dimensional Vlasov-Poisson solver based on piecewise-parabolic advection scheme, the formation of giant PSV is addressed numerically. For an infinitesimal external drive amplitude and wavenumber k, we demonstrate the existence of a window of chirped external drive frequency that leads to the formation of giant PSV. The linear, small amplitude, external drive, when chirped, is shown to couple effectively to the plasma and increase both streaming of "untrapped" and "trapped" particle fraction. The steady state attained after the external drive is turned off and is shown to lead to a giant PSV with multiple extrema and phase velocities, with excess density fraction, defined as the deviation from the Maxwellian background, Δ n / n 0 ≃ 20 % - 25 % . It is shown that the process depends on the chirp time duration Δt. The excess density fraction Δn/n0, which contains both trapped and untrapped particle contribution, is also seen to scale with Δt, only inhibited by the gradient of the distribution in velocity space. Both single step drive and multistep chirp processes are shown to lead to steady state giant PSV, with multiple extrema due to embedded holes and clumps, long after the external drive is turned off.

  3. Giant Viruses of Amoebas: An Update.

    PubMed

    Aherfi, Sarah; Colson, Philippe; La Scola, Bernard; Raoult, Didier

    2016-01-01

    During the 12 past years, five new or putative virus families encompassing several members, namely Mimiviridae, Marseilleviridae, pandoraviruses, faustoviruses, and virophages were described. In addition, Pithovirus sibericum and Mollivirus sibericum represent type strains of putative new giant virus families. All these viruses were isolated using amoebal coculture methods. These giant viruses were linked by phylogenomic analyses to other large DNA viruses. They were then proposed to be classified in a new viral order, the Megavirales, on the basis of their common origin, as shown by a set of ancestral genes encoding key viral functions, a common virion architecture, and shared major biological features including replication inside cytoplasmic factories. Megavirales is increasingly demonstrated to stand in the tree of life aside Bacteria, Archaea, and Eukarya, and the megavirus ancestor is suspected to be as ancient as cellular ancestors. In addition, giant amoebal viruses are visible under a light microscope and display many phenotypic and genomic features not found in other viruses, while they share other characteristics with parasitic microbes. Moreover, these organisms appear to be common inhabitants of our biosphere, and mimiviruses and marseilleviruses were isolated from human samples and associated to diseases. In the present review, we describe the main features and recent findings on these giant amoebal viruses and virophages. PMID:27047465

  4. Laser treatment of giant xanthelasma palpebrarum.

    PubMed

    Corradino, Bartolo; Di Lorenzo, Sara; Triolo, Antonio; Moschella, Francesco

    2015-11-01

    Xanthelasma palpebrarum is the most common cutaneous xanthoma. It typically presents in middle-aged and older adults, most often around the eyelids. The diagnosis is made clinically. Giant xanthelasmas palpebrarum are xanthelasmas that extensively affect the superior and inferior bilateral eyelids. Many techniques have been put forward for treating these lesions (surgical, laser, and chemical techniques), but we describe our experience in the treatment of giant xanthelasmas by ultrapulsed CO2 laser. Between 2009 and 2012, in the Division of Plastic and Reconstructive Surgery at the University of Palermo, 12 patients with giant xanthelasmas were treated using a CO2 laser. The laser parameters are as follows: frequency 20 Hz, energy 75 mJ, and power 1.5 W. Each laser session lasts 15 min; the treatment consists of three or four sessions that are carried out at intervals of 15 days. Patients were followed up after 2, 6, and 12 months. This technique is rapid and it is accepted very well by patients. The only disadvantage is a long healing time (10-15 days). The ultrapulsed CO2 laser, in experienced hands, is an excellent device that enables the complete removal of giant xanthelasmas with a minimally invasive but very effective technique.

  5. Vocal repertoire of the social giant otter.

    PubMed

    Leuchtenberger, Caroline; Sousa-Lima, Renata; Duplaix, Nicole; Magnusson, William E; Mourão, Guilherme

    2014-11-01

    According to the "social intelligence hypothesis," species with complex social interactions have more sophisticated communication systems. Giant otters (Pteronura brasiliensis) live in groups with complex social interactions. It is likely that the vocal communication of giant otters is more sophisticated than previous studies suggest. The objectives of the current study were to describe the airborne vocal repertoire of giant otters in the Pantanal area of Brazil, to analyze call types within different behavioral contexts, and to correlate vocal complexity with level of sociability of mustelids to verify whether or not the result supports the social intelligence hypothesis. The behavior of nine giant otters groups was observed. Vocalizations recorded were acoustically and statistically analyzed to describe the species' repertoire. The repertoire was comprised by 15 sound types emitted in different behavioral contexts. The main behavioral contexts of each sound type were significantly associated with the acoustic variable ordination of different sound types. A strong correlation between vocal complexity and sociability was found for different species, suggesting that the communication systems observed in the family mustelidae support the social intelligence hypothesis.

  6. Generation of a Chiral Giant Micelle.

    PubMed

    Ito, Thiago H; Salles, Airton G; Priebe, Jacks P; Miranda, Paulo C M L; Morgon, Nelson H; Danino, Dganit; Mancini, Giovanna; Sabadini, Edvaldo

    2016-08-23

    Over the past few years, chiral supramolecular assemblies have been successfully used for recognition, sensing and enantioselective transformations. Several approaches are available to control chirality of discrete assemblies (e.g., cages and capsules), but few are efficient in assuring chirality for micellar aggregates. Optically active amino acid-derived surfactants are commonly used to generate chiral spherical micelles. To circumvent this limitation, we benefited from the uniaxial growth of spherical micelles into long cylindrical micelles usually called wormlike or giant micelles, upon the addition of cosolutes. This paper describes the unprecedented formation of chiral giant micelles in aqueous solutions of cetyltrimethylammonium bromide (CTAB) upon increasing addition of enantiopure sodium salt of 1,1'-bi-2-naphthol (Na-binaphtholate) as a cosolute. Depending on the concentrations of CTAB and Na-binaphtholate, chiral gel-like systems are obtained. The transition from spherical to giant micellar structures was probed using rheology, cryo-transmission electron microscopy, polarimetry, and electronic circular dichroism (CD). CD can be effectively used to monitor the incorporation of Na-binaphtholate into the micelle palisade as well as to determine its transition to giant micellar structures. Our approach expands the scope for chirality induction in micellar aggregates bringing the possibility to generate "smart" chiral systems and an alternative asymmetric chiral environment to perform enantioselective transformations. PMID:27499127

  7. Ribosomes in the squid giant axon.

    PubMed

    Bleher, R; Martin, R

    2001-01-01

    Ribosome clusters, referred to as endoaxoplasmic plaques, were documented and quantitatively analyzed in the squid giant axon at the light and electron microscopic levels. The methods included nonspecific high affinity fluorescence staining of RNA by YOYO-1, specific immunofluorescence labeling of ribosomal RNA, electron energy loss spectroscopic mapping of ribosomal phosphorus, and conventional transmission electron microscopy. The endoaxoplasmic plaques were sharply defined, oval in shape, and less than 2 microm in diameter. While they were very numerous in the postsynaptic axonal area of the giant synapse, the frequency of occurrence was much lower in the peripheral giant axon, with a density of about 1 plaque/1000 microm3. Their distribution was random within axoplasm, with no preferential localization near the membrane. The several thousand ribosomes in a plaque usually were not membrane bound, but vesicular structures were observed in or near plaques; plaques were often surrounded by mitochondria. We conclude that ribosomes, a requisite machinery for protein synthesis, are present in the squid giant axon in discrete configurations.

  8. Reading on the Shoulders of Giants

    ERIC Educational Resources Information Center

    Ben-Chaim, Michael; Riendeau, Michael

    2012-01-01

    Reflecting on his successful scientific career, Isaac Newton highlighted his intellectual debt to his predecessors. "If I have seen further," he wrote, "it was "only" by standing on the shoulders of giants." The authors have chosen the title of their article as a token of recognition of their debt to the teachings of Newton and other intellectuals…

  9. Vocal repertoire of the social giant otter.

    PubMed

    Leuchtenberger, Caroline; Sousa-Lima, Renata; Duplaix, Nicole; Magnusson, William E; Mourão, Guilherme

    2014-11-01

    According to the "social intelligence hypothesis," species with complex social interactions have more sophisticated communication systems. Giant otters (Pteronura brasiliensis) live in groups with complex social interactions. It is likely that the vocal communication of giant otters is more sophisticated than previous studies suggest. The objectives of the current study were to describe the airborne vocal repertoire of giant otters in the Pantanal area of Brazil, to analyze call types within different behavioral contexts, and to correlate vocal complexity with level of sociability of mustelids to verify whether or not the result supports the social intelligence hypothesis. The behavior of nine giant otters groups was observed. Vocalizations recorded were acoustically and statistically analyzed to describe the species' repertoire. The repertoire was comprised by 15 sound types emitted in different behavioral contexts. The main behavioral contexts of each sound type were significantly associated with the acoustic variable ordination of different sound types. A strong correlation between vocal complexity and sociability was found for different species, suggesting that the communication systems observed in the family mustelidae support the social intelligence hypothesis. PMID:25373985

  10. Giant light enhancement in atomic clusters

    SciTech Connect

    Gadomsky, O. N. Gadomskaya, I. V.; Altunin, K. K.

    2009-07-15

    We show that the polarizing effect of the atoms in an atomic cluster can lead to full compensation of the radiative damping of excited atomic states, a change in the sign of the dispersion of the atomic polarizability, and giant light enhancement by the atomic cluster.

  11. Giant retroperitoneal cyst in an adult male.

    PubMed

    Egawa, S; Satoh, T; Suyama, K; Uchida, T; Iwabuchi, K; Koshiba, K

    1996-07-01

    This paper presents a case of a symptomatic giant retroperitoneal cyst in an adult male. The unilocular cyst was excised successfully with resolution of the attendant symptoms. Histological findings of the cyst wall suggested a lymphangiomatous etiology. Any good risk patient found to harbor such a cyst should undergo complete excision in view of the potential for the development of symptoms and complications.

  12. Giant Viruses of Amoebas: An Update

    PubMed Central

    Aherfi, Sarah; Colson, Philippe; La Scola, Bernard; Raoult, Didier

    2016-01-01

    During the 12 past years, five new or putative virus families encompassing several members, namely Mimiviridae, Marseilleviridae, pandoraviruses, faustoviruses, and virophages were described. In addition, Pithovirus sibericum and Mollivirus sibericum represent type strains of putative new giant virus families. All these viruses were isolated using amoebal coculture methods. These giant viruses were linked by phylogenomic analyses to other large DNA viruses. They were then proposed to be classified in a new viral order, the Megavirales, on the basis of their common origin, as shown by a set of ancestral genes encoding key viral functions, a common virion architecture, and shared major biological features including replication inside cytoplasmic factories. Megavirales is increasingly demonstrated to stand in the tree of life aside Bacteria, Archaea, and Eukarya, and the megavirus ancestor is suspected to be as ancient as cellular ancestors. In addition, giant amoebal viruses are visible under a light microscope and display many phenotypic and genomic features not found in other viruses, while they share other characteristics with parasitic microbes. Moreover, these organisms appear to be common inhabitants of our biosphere, and mimiviruses and marseilleviruses were isolated from human samples and associated to diseases. In the present review, we describe the main features and recent findings on these giant amoebal viruses and virophages. PMID:27047465

  13. Ultra-sharp plasmonic resonances from monopole optical nanoantenna phased arrays

    SciTech Connect

    Li, Shi-Qiang; Bruce Buchholz, D.; Zhou, Wei; Ketterson, John B.; Ocola, Leonidas E.; Sakoda, Kazuaki; Chang, Robert P. H.

    2014-06-09

    Diffractively coupled plasmonic resonances possess both ultra-sharp linewidths and giant electric field enhancement around plasmonic nanostructures. They can be applied to create a new generation of sensors, detectors, and nano-optical devices. However, all current designs require stringent index-matching at the resonance condition that limits their applicability. Here, we propose and demonstrate that it is possible to relieve the index-matching requirement and to induce ultra-sharp plasmon resonances in an ordered vertically aligned optical nano-antenna phased array by transforming a dipole resonance to a monopole resonance with a mirror plane. Due to the mirror image effect, the monopole resonance not only retained the dipole features but also enhanced them. The engineered resonances strongly suppressed the radiative decay channel, resulting in a four-order of magnitude enhancement in local electric field and a Q-factor greater than 200.

  14. Chiral metamaterials with negative refractive index based on four “U” split ring resonators

    SciTech Connect

    Li, Zhaofeng; Zhao, Rongkuo; Koschny, Thomas; Kafesaki, Maria; Alici, Kamil Boratay; Colak, Evrim; Caglayan, Humeyra; Ozbay, Ekmel; Soukoulis, C.M.

    2010-08-23

    A uniaxial chiral metamaterial is constructed by double-layered four 'U' split ring resonators mutually twisted by 90{sup o}. It shows a giant optical activity and circular dichroism. The retrieval results reveal that a negative refractive index is realized for circularly polarized waves due to the large chirality. The experimental results are in good agreement with the numerical results.

  15. Interaction of Rydberg atoms in circular states with the alkaline-earth Ca(4s{sup 2}) and Sr(5s{sup 2}) atoms

    SciTech Connect

    Mironchuk, E. S.; Narits, A. A.; Lebedev, V. S.

    2015-11-15

    The resonant mechanism of interaction of alkaline-earth atoms having a low electron affinity to Rydberg atoms in circular (l = vertical bar m vertical bar = n–1) and near-circular states has been studied. To describe the dynamics of resonant processes accompanied by nonadiabatic transitions between ionic and Rydberg covalent terms of a quasimolecule, an approach based on the integration of coupled equations for the probability amplitudes has been developed taking into account the possibility of the decay of an anion in the Coulomb field of the positive ionic core of a highly excited atom. The approach involves the specific features of the problem associated with the structure of the wavefunction of a Rydberg electron in states with high orbital angular momenta l ∼ n–1. This approach provides a much more accurate description of the dynamics of electronic transitions at collisions between atoms than that within the modified semiclassical Landau–Zener model. In addition, this approach makes it possible to effectively take into account many channels of the problem. The cross sections for resonant quenching of Rydberg states of the Li(nlm) atom with given principal n, orbital l = n–1, and magnetic m quantum numbers at thermal collisions with the Ca(4s{sup 2}) and Sr(5s{sup 2}) atoms have been calculated. The dependences of the results on n, m, and angle α between the relative velocity of the atoms and the normal to the plane of the orbit of the Rydberg electron have been obtained. The influence of orientational effects on the efficiency of the collisional destruction of circular and near-circular states has been studied. The results indicate a higher stability of such states to their perturbations by neutral particles as compared to usually studied nl states with low values of l (l ≪ n)

  16. Interaction of Rydberg atoms in circular states with the alkaline-earth Ca(4 s 2) and Sr(5 s 2) atoms

    NASA Astrophysics Data System (ADS)

    Mironchuk, E. S.; Narits, A. A.; Lebedev, V. S.

    2015-11-01

    The resonant mechanism of interaction of alkaline-earth atoms having a low electron affinity to Rydberg atoms in circular ( l = | m| = n-1) and near-circular states has been studied. To describe the dynamics of resonant processes accompanied by nonadiabatic transitions between ionic and Rydberg covalent terms of a quasimolecule, an approach based on the integration of coupled equations for the probability amplitudes has been developed taking into account the possibility of the decay of an anion in the Coulomb field of the positive ionic core of a highly excited atom. The approach involves the specific features of the problem associated with the structure of the wavefunction of a Rydberg electron in states with high orbital angular momenta l ~ n-1. This approach provides a much more accurate description of the dynamics of electronic transitions at collisions between atoms than that within the modified semiclassical Landau-Zener model. In addition, this approach makes it possible to effectively take into account many channels of the problem. The cross sections for resonant quenching of Rydberg states of the Li( nlm) atom with given principal n, orbital l = n-1, and magnetic m quantum numbers at thermal collisions with the Ca(4 s 2) and Sr(5 s 2) atoms have been calculated. The dependences of the results on n, m, and angle α between the relative velocity of the atoms and the normal to the plane of the orbit of the Rydberg electron have been obtained. The influence of orientational effects on the efficiency of the collisional destruction of circular and near-circular states has been studied. The results indicate a higher stability of such states to their perturbations by neutral particles as compared to usually studied nl states with low values of l ( l ≪ n).

  17. Mapping of D4S98/S114/S113 confines the Huntington's defect to a reduced physical region at the telomere of chromosome 4.

    PubMed

    Whaley, W L; Michiels, F; MacDonald, M E; Romano, D; Zimmer, M; Smith, B; Leavitt, J; Bucan, M; Haines, J L; Gilliam, T C

    1988-12-23

    The dominant gene defect in Huntington's disease (HD) is linked to the DNA marker D4S10, near the telomere of the chromosome 4 short arm. Two other markers, D4S43 and D4S95, are closer, but still proximal to the HD gene in 4p16.3. We have characterized a new locus, D4S114, identified by cloning the end of a NotI fragment resolved by pulsed-field gel electrophoresis. D4S114 was localized distal to D4S43 and D4S95 by both physical and genetic mapping techniques. The "end"-clone overlaps a previously isolated NotI "linking" clone, and is within 150 kb of a second "linking" clone defining D4S113. Restriction fragment length polymorphisms for D4S113 and D4S114, one of which is identical to a SacI polymorphism detected by the anonymous probe pBS731B-C (D4S98), were typed for key crossovers in HD and reference pedigrees. The data support the locus order D4S10-(D4S43, D4S95)-D4S98/S114/S113-HD-telomere. The D4S98/S114/S113 cluster therefore represents the nearest cloned sequences to HD, and provides a valuable new point for launching directional cloning strategies to isolate and characterize this disease gene.

  18. Emissions in potassium vapour under 4S1/2-7S1/2 two-photon nsec excitation

    NASA Astrophysics Data System (ADS)

    Pentaris, D.; Chatzikyriakos, G.; Armyras, A.; Efthimiopoulos, T.

    2010-11-01

    The two-photon excitation of 4S1/2-7S1/2 transition of potassium atoms is studied. Several coherent emissions and processes are possible, such as parametric four-wave (PFWM), parametric six-wave (PSWM) mixing and competition with the stimulated hyper Raman (SHRS) and the amplified spontaneous emission (ASE). The radiations at the transitions 6P3/2,1/2-4S1/2, 6S1/2-4P3/2,1/2 and 5P3/2,1/2-4S1/2 are emitted only in the forward direction (indicating a parametric process), while the radiation at the transition 4P3/2,1/2-4S1/2 is emitted in the forward and in the backward direction, indicating an ASE process.

  19. Experiments with Helmholtz Resonators.

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    1996-01-01

    Presents experiments that use Helmholtz resonators and have been designed for a sophomore-level course in oscillations and waves. Discusses the theory of the Helmholtz resonator and resonance curves. (JRH)

  20. Structural principles for computational and de novo design of 4Fe-4S metalloproteins.

    PubMed

    Nanda, Vikas; Senn, Stefan; Pike, Douglas H; Rodriguez-Granillo, Agustina; Hansen, Will A; Khare, Sagar D; Noy, Dror

    2016-05-01

    Iron-sulfur centers in metalloproteins can access multiple oxidation states over a broad range of potentials, allowing them to participate in a variety of electron transfer reactions and serving as catalysts for high-energy redox processes. The nitrogenase FeMoCO cluster converts di-nitrogen to ammonia in an eight-electron transfer step. The 2(Fe4S4) containing bacterial ferredoxin is an evolutionarily ancient metalloprotein fold and is thought to be a primordial progenitor of extant oxidoreductases. Controlling chemical transformations mediated by iron-sulfur centers such as nitrogen fixation, hydrogen production as well as electron transfer reactions involved in photosynthesis are of tremendous importance for sustainable chemistry and energy production initiatives. As such, there is significant interest in the design of iron-sulfur proteins as minimal models to gain fundamental understanding of complex natural systems and as lead-molecules for industrial and energy applications. Herein, we discuss salient structural characteristics of natural iron-sulfur proteins and how they guide principles for design. Model structures of past designs are analyzed in the context of these principles and potential directions for enhanced designs are presented, and new areas of iron-sulfur protein design are proposed. This article is part of a Special issue entitled Biodesign for Bioenergetics--the design and engineering of electronic transfer cofactors, protein networks, edited by Ronald L. Koder and J.L Ross Anderson.

  1. Extending the Family of V(4+) S=(1/2) Kagome Antiferromagnets.

    PubMed

    Clark, Lucy; Aidoudi, Farida H; Black, Cameron; Arachchige, Kasun S A; Slawin, Alexandra M Z; Morris, Russell E; Lightfoot, Philip

    2015-12-14

    The ionothermal synthesis, structure, and magnetic susceptibility of a novel inorganic-organic hybrid material, imidazolium vanadium(III,IV) oxyfluoride [C3 H5 N2 ][V9 O6 F24 (H2 O)2 ] (ImVOF) are presented. The structure consists of inorganic vanadium oxyfluoride slabs with kagome layers of V(4+) S=${{ 1/2 }}$ ions separated by a mixed valence layer. These inorganic slabs are intercalated with imidazolium cations. Quinuclidinium (Q) and pyrazinium (Pyz) cations can also be incorporated into the hybrid structure type to give QVOF and PyzVOF analogues, respectively. The highly frustrated topology of the inorganic slabs, along with the quantum nature of the magnetism associated with V(4+) , means that these materials are excellent candidates to host exotic magnetic ground states, such as the highly sought quantum spin liquid. Magnetic susceptibility measurements of all samples suggest an absence of conventional long-range magnetic order down to 2 K despite considerable antiferromagnetic exchange.

  2. Structural principles for computational and de novo design of 4Fe-4S metalloproteins.

    PubMed

    Nanda, Vikas; Senn, Stefan; Pike, Douglas H; Rodriguez-Granillo, Agustina; Hansen, Will A; Khare, Sagar D; Noy, Dror

    2016-05-01

    Iron-sulfur centers in metalloproteins can access multiple oxidation states over a broad range of potentials, allowing them to participate in a variety of electron transfer reactions and serving as catalysts for high-energy redox processes. The nitrogenase FeMoCO cluster converts di-nitrogen to ammonia in an eight-electron transfer step. The 2(Fe4S4) containing bacterial ferredoxin is an evolutionarily ancient metalloprotein fold and is thought to be a primordial progenitor of extant oxidoreductases. Controlling chemical transformations mediated by iron-sulfur centers such as nitrogen fixation, hydrogen production as well as electron transfer reactions involved in photosynthesis are of tremendous importance for sustainable chemistry and energy production initiatives. As such, there is significant interest in the design of iron-sulfur proteins as minimal models to gain fundamental understanding of complex natural systems and as lead-molecules for industrial and energy applications. Herein, we discuss salient structural characteristics of natural iron-sulfur proteins and how they guide principles for design. Model structures of past designs are analyzed in the context of these principles and potential directions for enhanced designs are presented, and new areas of iron-sulfur protein design are proposed. This article is part of a Special issue entitled Biodesign for Bioenergetics--the design and engineering of electronic transfer cofactors, protein networks, edited by Ronald L. Koder and J.L Ross Anderson. PMID:26449207

  3. On the Fermi-GBM Event 0.4 s after GW150914

    NASA Astrophysics Data System (ADS)

    Greiner, J.; Burgess, J. M.; Savchenko, V.; Yu, H.-F.

    2016-08-01

    In view of the recent report by Connaughton et al., we analyze continuous time-tagged event (TTE) data of Fermi-gamma-ray burst monitor (GBM) around the time of the gravitational-wave event GW 150914. We find that after proper accounting for low-count statistics, the GBM transient event at 0.4 s after GW 150914 is likely not due to an astrophysical source, but consistent with a background fluctuation, removing the tension between the INTEGRAL/ACS non-detection and GBM. Additionally, reanalysis of other short GRBs shows that without proper statistical modeling the fluence of faint events is over-predicted, as verified for some joint GBM–ACS detections of short GRBs. We detail the statistical procedure to correct these biases. As a result, faint short GRBs, verified by ACS detections, with significances in the broadband light curve even smaller than that of the GBM–GW150914 event are recovered as proper non-zero source, while the GBM–GW150914 event is consistent with zero fluence.

  4. Crystallographic analysis of the structure of livingstonite HgSb4S8 from refined data

    NASA Astrophysics Data System (ADS)

    Borisov, S. V.; Pervukhina, N. V.; Magarill, S. A.; Kuratieva, N. V.; Vasil'Ev, V. I.

    2010-03-01

    An X-ray diffraction study of mineral livingstonite (HgSb4S8) from Khaydarkan (Kyrgyzstan) has been performed on a Bruker Nonius X8Apex diffractometer with a 4K CCD detector ( R = 0.031). The unit-cell parameters were found to be a = 30.1543(10) Å, b = 3.9953(2) Å, c = 21.4262(13) Å, β = 104.265(1)°, V = 2501.7(2) Å3, Z = 8, d calcd = 5.013 g/cm3, and sp. gr. A2/ a. It was confirmed that livingstonite belongs to rod-layers structures. In one type of layer, two double Sb2S4 chains are bound by disulfide groups [S2]2- (S-S 2.078(2) Å); in the other type, these chains are bound via Hg2+ cations. A crystallographic analysis confirmed the existence of independent pseudotranslational ordering in the cation and anion matrices, which is characteristic of the lozenge-like structures of sulfides and sulfosalts.

  5. THE RESONANT TRANS-NEPTUNIAN POPULATIONS

    SciTech Connect

    Gladman, B.; Lawler, S. M.; Van Laerhoven, C.; Petit, J.-M.; Rousselot, P.; Kavelaars, J.; Jones, R. L.; Parker, J. Wm.; Bieryla, A.; Nicholson, P.; Ashby, M. L. N.

    2012-07-15

    The trans-Neptunian objects (TNOs) trapped in mean-motion resonances with Neptune were likely emplaced there during planet migration late in the giant-planet formation process. We perform detailed modeling of the resonant objects detected in the Canada-France Ecliptic Plane Survey (CFEPS) in order to provide population estimates and, for some resonances, constrain the complex internal orbital element distribution. Detection biases play a critical role because phase relationships with Neptune make object discovery more likely at certain longitudes. This paper discusses the 3:2, 5:2, 2:1, 3:1, 5:1, 4:3, 5:3, 7:3, 5:4, and 7:4 mean-motion resonances, all of which had CFEPS detections, along with our upper limit on 1:1 Neptune Trojans (which is consistent with their small population estimated elsewhere). For the plutinos (TNOs in the 3:2 resonance) we refine the orbital element distribution given by Kavelaars et al. in 2009 and show that steep H-magnitude distributions (N(H){proportional_to}10{sup {alpha}H}, with {alpha} = 0.8-0.9) are favored in the range H{sub g} = 8-9, and confirm that this resonance does not share the inclination distribution of the classical Kuiper Belt. We give the first population estimate for the 5:2 resonance and find that, to within the uncertainties, the population is equal to that of the 3:2 ({approx_equal}13,000 TNOs with H{sub g} < 9.16), whereas the 2:1 population is smaller by a factor of 3-4 compared to the other two resonances. We also measure significant populations inhabiting the 4:3, 5:3, 7:3, 5:4, 7:4, 3:1, and 5:1 resonances, with H{sub g} < 9.16 (D > 100 km) populations in the thousands. We compare our intrinsic population and orbital element distributions with several published models of resonant-TNO production; the most striking discrepancy is that resonances beyond the 2:1 are in reality more heavily populated than in published models.

  6. Classified Computer Configuration Control System (C{sup 4}S), Revision 3, Database Administrator`s Guide

    SciTech Connect

    O`Callaghan, P.B.; Nelson, R.A.; Grambihler, A.J.

    1994-04-01

    This document provides a guide for database administration and specific information for the Classified Computer Configuration Control System (C{sup 4}S). As a guide, this document discusses required database administration functions for the set up of database tables and for users of the system. It is assumed that general and user information has been obtained from the Classified Computer Configuration Control System (C{sup 4}S), Revision 3, User`s Information (WHC 1994).

  7. A Nonradioactive Assay to Measure Production and Processing of Ribosomal RNA by 4sU-Tagging.

    PubMed

    Burger, Kaspar; Eick, Dirk

    2016-01-01

    In vivo metabolic pulse labeling is a classical approach to assess production and processing of ribosomal RNA (rRNA). However, conventional labeling techniques can be indirect and require work with radioactivity. Here, we describe in detail a protocol for in vivo metabolic labeling, purification, and readout of nascent rRNA by 4-thiouridine (4sU). We propose 4sU labeling as standard nonradioactive technique for the analysis of rRNA metabolism during ribosome biogenesis. PMID:27576715

  8. Spontaneous thrombosis of giant intracranial aneurysm and posterior cerebral artery followed by also spontaneous recanalization

    PubMed Central

    de Aguiar, Guilherme Brasileiro; Pagotto, Mário Vítor Caldeira; Conti, Mario Luiz Marques; Veiga, José Carlos Esteves

    2016-01-01

    Background: Spontaneous complete thrombosis of a giant aneurysm and its parent artery is a rare event. Their spontaneous recanalization is even rarer, with few reports. Case Description: A 17-year-old male patient presenting blurred vision and headache, with a history of seizures, was referred to our service. After further investigation with cranial computed tomography, magnetic resonance imaging (MRI), and cerebral angiography (CAG), it was diagnosed a thrombosed aneurysm of the posterior cerebral artery (PCA) and also complete thrombosis of the PCA. Three years later, he experienced visual worsening. A new MRI scan indicated flow both through the aneurysm and the left PCA, which was further confirmed by CAG. We decided for a noninterventional treatment combined with strict clinical follow-up. The patient continues to present with the previous neurological deficit, without recurrence of headaches. Conclusions: Thrombosis is not the final event in the natural history of giant aneurysms, and partial thrombosis does not preclude the risk of rupture. Thrombosed aneurysms may display additional growth brought about by wall dissections or intramural hemorrhages. Their treatment may be either surgical or involve endovascular procedures such as embolization. Thrombosed giant aneurysms are dynamic and unstable lesions. A noninterventional treatment is feasible, but aneurysmal growth or recanalization may suggest the need for a more active intervention. PMID:26958421

  9. Origin of the obliquities of the giant planets in mutual interactions in the early Solar System.

    PubMed

    Brunini, Adrián

    2006-04-27

    The origin of the spin-axis orientations (obliquities) of the giant planets is a fundamental issue because if the obliquities resulted from tangential collisions with primordial Earth-sized protoplanets, then they are related to the masses of the largest planetesimals out of which the planets form. A problem with this mechanism, however, is that the orbital planes of regular satellites would probably be uncorrelated with the obliquities, contrary to observations. Alternatively, they could have come from an external twist that affected the orientation of the Solar System plane; but in this model, the outer planets must have formed too rapidly, before the event that produced the twist. Moreover, the model cannot be quantitatively tested. Here I show that the present obliquities of the giant planets were probably achieved when Jupiter and Saturn crossed the 1:2 orbital resonance during a specific migration process: different migration scenarios cannot account for the large observed obliquities. The existence of the regular satellites of the giant planets does not represent a problem in this model because, although they formed soon after the planetary formation, they can follow the slow evolution of the equatorial plane it produces. PMID:16641989

  10. Regenerative feedback resonant circuit

    DOEpatents

    Jones, A. Mark; Kelly, James F.; McCloy, John S.; McMakin, Douglas L.

    2014-09-02

    A regenerative feedback resonant circuit for measuring a transient response in a loop is disclosed. The circuit includes an amplifier for generating a signal in the loop. The circuit further includes a resonator having a resonant cavity and a material located within the cavity. The signal sent into the resonator produces a resonant frequency. A variation of the resonant frequency due to perturbations in electromagnetic properties of the material is measured.

  11. Hilda Asteroid Colors: Insight into Giant Planet Migration?

    NASA Astrophysics Data System (ADS)

    Sharkey, Benjamin; Ryan, Erin L.; Woodward, Charles E.; Noll, Keith S.

    2016-01-01

    The Hilda asteroids are a unique population of small bodies that are locked in a 3:2 mean motion resonance with Jupiter. Unlike other resonances in the asteroid belt, the 3:2 is a stable resonance at 3.95 AU. Objects at this resonance have stable orbits for at least 2 GYr and, more likely, for the age of the Solar System. In an instantaneous top down view of the solar system, the Hildas approximately trace a triangle with over-densities of asteroids near the L3, L4 and L5 Jovian Lagrange points. This configuration is cited as evidence that Jupiter migrated inwards by ~0.4 AU. Stable Hilda orbits have mean eccentricities of 0.16 with typical perihelia of 3.15 AU. These latter properties, in terms of observability and accessibility to spacecraft, are a major advantage that distinguishes the Hildas from other populations of potential scientific interest such as the Jovian Trojans. The Outer Main Belt (OMB) also has many objects that may have originated in the outer protoplanetary disk (OPD). However, the OMB appears to be more mixed with objects from elsewhere in the Main Belt and enjoys only a small advantage in terms of brightness for a given diameter and albedo. The intrinsic collisional probability for objects in the Hilda population is also a factor of 3 to 5 less than the collisional probabilities for Trojan and OMB populations. Thus, the Hildas likely represent a significant population of objects unaltered due to collisional processing. Here we discuss findings of our ongoing NASA Planetary Astronomy program to obtain Sloan optical (g' r' i' z') colors of Hilda-group asteroids. The loci of these colors are compared to the Kuiper Belt populations to test post-formation migration effects of the giant planets in our solar system on the small body population. In part, this work was conducted as part of a University of Minnesota Undergraduate Research Scholarship, and is supported by NASA PAST Award NNX13AJ11G.

  12. STATISTICAL STUDY OF THE EARLY SOLAR SYSTEM'S INSTABILITY WITH FOUR, FIVE, AND SIX GIANT PLANETS

    SciTech Connect

    Nesvorny, David; Morbidelli, Alessandro

    2012-10-01

    Several properties of the solar system, including the wide radial spacing and orbital eccentricities of giant planets, can be explained if the early solar system evolved through a dynamical instability followed by migration of planets in the planetesimal disk. Here we report the results of a statistical study, in which we performed nearly 10{sup 4} numerical simulations of planetary instability starting from hundreds of different initial conditions. We found that the dynamical evolution is typically too violent, if Jupiter and Saturn start in the 3:2 resonance, leading to ejection of at least one ice giant from the solar system. Planet ejection can be avoided if the mass of the transplanetary disk of planetesimals was large (M{sub disk} {approx}> 50 M{sub Earth}), but we found that a massive disk would lead to excessive dynamical damping (e.g., final e{sub 55} {approx}< 0.01 compared to present e{sub 55} = 0.044, where e{sub 55} is the amplitude of the fifth eccentric mode in the Jupiter's orbit), and to smooth migration that violates constraints from the survival of the terrestrial planets. Better results were obtained when the solar system was assumed to have five giant planets initially, and one ice giant, with mass comparable to that of Uranus and Neptune, was ejected into interstellar space by Jupiter. The best results were obtained when the ejected planet was placed into the external 3:2 or 4:3 resonance with Saturn and M{sub disk} {approx_equal} 20 M{sub Earth}. The range of possible outcomes is rather broad in this case, indicating that the present solar system is neither a typical nor expected result for a given initial state, and occurs, in best cases, with only a {approx_equal}5% probability (as defined by the success criteria described in the main text). The case with six giant planets shows interesting dynamics but does offer significant advantages relative to the five-planet case.

  13. Ultrabass Sounds of the Giant Star xi Hya

    NASA Astrophysics Data System (ADS)

    2002-05-01

    First Observations of Solar-type Oscillations in a Star Very Different from the Sun Summary About 30 years ago, astronomers realised that the Sun resonates like a giant musical instrument with well-defined periods (frequencies). It forms a sort of large, spherical organ pipe. The energy that excites these sound waves comes from the turbulent region just below the Sun's visible surface. Observations of the solar sound waves (known as " helioseismology ") have resulted in enormous progress in the exploration of the interior of the Sun, otherwise hidden from view. As is the case on Earth, seismic techniques can be applied and the detailed interpretation of the observed oscillation periods has provided quite accurate information about the structure and motions inside the Sun, our central star. It has now also become possible to apply this technique to some solar-type stars. The first observations concerned the northern star eta Bootis (cf. ESO PR 16/94 ). Last year, extensive and much more accurate observations with the 1.2-m Swiss telescope at the ESO La Silla Observatory proved that Alpha Centauri , a solar "twin", behaves very much like the Sun (cf. ESO PR 15/01 ), and that some of the periods are quite similar to those in the Sun. These new observational data were of a superb quality, and that study marked a true break-through in the new research field of " asteroseismology " (seismology of the stars) for solar-type stars. But what about other types of stars, for instance those that are much larger than the Sun? Based on an extremely intensive observing project with the same telescope, an international group of astronomers [1] has found that the giant star xi Hya ("xi" is the small greek letter [2]; "Hya" is an abbreviation of "Hydrae") behaves like a giant sub-ultra-bass instrument . This star is located in the constellation Hydra (the Water-Monster) at a distance of 130 light-years, it has a radius about 10 times that of the Sun and its luminosity is about 60

  14. Sound isolation and giant linear nonreciprocity in a compact acoustic circulator.

    PubMed

    Fleury, Romain; Sounas, Dimitrios L; Sieck, Caleb F; Haberman, Michael R; Alù, Andrea

    2014-01-31

    Acoustic isolation and nonreciprocal sound transmission are highly desirable in many practical scenarios. They may be realized with nonlinear or magneto-acoustic effects, but only at the price of high power levels and impractically large volumes. In contrast, nonreciprocal electromagnetic propagation is commonly achieved based on the Zeeman effect, or modal splitting in ferromagnetic atoms induced by a magnetic bias. Here, we introduce the acoustic analog of this phenomenon in a subwavelength meta-atom consisting of a resonant ring cavity biased by a circulating fluid. The resulting angular momentum bias splits the ring's azimuthal resonant modes, producing giant acoustic nonreciprocity in a compact device. We applied this concept to build a linear, magnetic-free circulator for airborne sound waves, observing up to 40-decibel nonreciprocal isolation at audible frequencies. PMID:24482477

  15. Synthesis, Structure, and Characterization of Cu4S10(4-methylpyridine)4

    NASA Technical Reports Server (NTRS)

    Hepp, Aloysius F.; Richman, Robert M.; Duraj, Stan A.; Andras, Maria T.; Moore, Hall L.; Sabat, Michal; Eckles, William E.; Martuch, Robert A.

    1996-01-01

    The title compound, Cu4S10(4-methylpyridine)(sub 4) (dot) 4-methylpyridine was prepared by three different reactions: the oxidation of copper powder by sulfur and the reaction of copper (I) sulfide (or CuBr (dot) SMe2) with excess sulfur, both in the coordinating solvent, 4-methylpyridine. Red crystals of the compound obtained by layering with hexanes were subjected to single crystal X-ray diffraction. The structure was refined to R = 0.026 and R(sub w) = 0.036 in a space group P1bar (No. 2), with Z = 2, a = 13.983 (2) A, b = 15.384 (2) A, c = 9.660 (1) A, alpha = 93.87 (1)deg., beta = 93.38 (1)deg., gamma = 99.78 (1)deg., V = 2037.9 (9) A(exp 3). The compound has approximate S(sub 4) symmetry and consists of two pentasulfide chains linking four Cu(I) ions, each with a corrdinating 2-methylpyridine. The infrared spectrum was dominated by absorption due to coordinated 4-methylpyridine with several low-energy peaks attributable to S-S stretches, which were also observed by Raman spectroscopy. A featureless electronic absorption spectrum yielded a single peak in the near ultraviolet upon computer enhancement (lambda = 334 nm, epsilon = 10,000), most likely an intraligand transition. Cyclic voltammetry indicates that the polysulfide complex undergoes irrversible oxidation and reduction at +0.04 and -0.34 V vs. SCE, respectively, at 298 K in 4-methylpyridine when swept at 20 mV/sec. The electrochemical behavior was unvaried even at sweep rates as high as 100 V/sec.

  16. Celestite (SrSO 4(s)) solubility in water, seawater and NaCl solution

    NASA Astrophysics Data System (ADS)

    Reardon, E. J.; Armstrong, D. K.

    1987-01-01

    Celestite solubility measurements have been conducted in pure water at temperatures from 10 to 90°C. Equilibrium was achieved with respect to a crystalline solid phase from both undersaturated and supersaturated solutions. The measurements show that the solubility undergoes a maximum near 20°C. LogK values for the solubility reaction are adequately described by the following expression over the temperature range 283.15 to 363.15 K: - logK= -35.3106+0.00422837 T+318312/ T2+14.99586 logT. The following thennodynamic values for the dissolution reaction of SrSO 4(s), at 25°C have been derived: ΔGR0 = 37852 ± 30 Jmol -1ΔHR0 = -1668±920 Jmol -1ΔSR0= -132.6±3.2 JK-1mol -1 Celestite solubility measurements were also determined in NaCl solutions up to 5 m concentration and from 10 to 40°C. These data are in good agreement with the work of StrÜbel (1966), who reports solubility measurements to temperatures of 100°C. The application of the Pitzer relations and the solubility constants determined in this study to calculate celestite solubility in NaCl solutions yields excellent agreement between predicted values and experimental measurements over the entire range of temperature and NaCl concentration conditions. For the limited number of solubility measurements in seawater-type solutions and mixed-salt brines, the agreement using the Pitzer relations is within three percent of the measured solubility.

  17. The properties of planets around giant stars

    NASA Astrophysics Data System (ADS)

    Jones, M. I.; Jenkins, J. S.; Bluhm, P.; Rojo, P.; Melo, C. H. F.

    2014-06-01

    Context. More than 50 exoplanets have been found around giant stars, revealing different properties when compared to planets orbiting solar-type stars. In particular, they are super-Jupiters and are not found orbiting interior to ~0.5 AU. Aims: We are conducting a radial velocity study of a sample of 166 giant stars aimed at studying the population of close-in planets orbiting giant stars and how their orbital and physical properties are influenced by the post-MS evolution of the host star. Methods: We have collected multiepoch spectra for all of the targets in our sample. We have computed precision radial velocities from FECH/CHIRON and FEROS spectra, using the I2 cell technique and the simultaneous calibration method, respectively. Results: We present the discovery of a massive planet around the giant star HIP 105854. The best Keplerian fit to the data leads to an orbital distance of 0.81 ± 0.03 AU, an eccentricity of 0.02 ± 0.03 and a projected mass of 8.2 ± 0.2 MJ. With the addition of this new planet discovery, we performed a detailed analysis of the orbital properties and mass distribution of the planets orbiting giant stars. We show that there is an overabundance of planets around giant stars with a ~ 0.5 - 0.9 AU, which might be attributed to tidal decay. Additionally, these planets are significantly more massive than those around MS and subgiant stars, suggesting that they grow via accretion either from the stellar wind or by mass transfer from the host star. Finally, we show that planets around evolved stars have lower orbital eccentricities than those orbiting solar-type stars, which suggests that they are either formed in different conditions or that their orbits are efficiently circularized by interactions with the host star. Based on observations collected at La Silla - Paranal Observatory under programs IDs 085.C-0557, 087.C.0476, 089.C-0524 and 090.C-0345.The RV Table is only available at the CDS via anonymous ftp to http

  18. An Extremely Lithium-rich Bright Red Giant in the Globular Cluster M3

    NASA Astrophysics Data System (ADS)

    Kraft, Robert P.; Peterson, Ruth C.; Guhathakurta, Puragra; Sneden, Christopher; Fulbright, Jon P.; Langer, G. Edward

    1999-06-01

    We have serendipitously discovered an extremely lithium-rich star on the red giant branch of the globular cluster M3 (NGC 5272). An echelle spectrum obtained with the Keck I High-Resolution Echelle Spectrograph reveals a Li I λ6707 resonance doublet of 520 mÅ equivalent width, and our analysis places the star among the most Li-rich giants known: logε(Li)~=+3.0. We determine the elemental abundances of this star, IV-101, and three other cluster members of similar luminosity and color and conclude that IV-101 has abundance ratios typical of giants in M3 and M13 that have undergone significant mixing. We discuss mechanisms by which a low-mass star may be so enriched in Li, focusing on the mixing of material processed by the hydrogen-burning shell just below the convective envelope. While such enrichment could conceivably happen only rarely, it may in fact regularly occur during giant-branch evolution but be rarely detected because of rapid subsequent Li depletion. Based on observations obtained with the Keck I Telescope of the W. M. Keck Observatory, which is operated by the California Association for Research in Astronomy (CARA), Inc., on behalf of the University of California and the California Institute of Technology. This Letter is dedicated to the memory of our beloved colleague Ed Langer, who died after a brief illness on February 16, 1999. Ed brought a unique theoretical perspective to our globular cluster abundance studies. His career truly embodied the academic ideals of inspiration in both teaching and research. He made friends wherever he traveled, and was an inspiration to students. We will miss him greatly.

  19. Giant oil fields of the Gulf Coast area

    SciTech Connect

    Haeberle, F.R.

    1993-09-01

    The 134 giant fields in the Gulf Coastal area contain 29% of the total giant-field reserves. Cumulative production is 32% of the giant-field cumulative total and 20% of the United States cumulative production. Eighty-nine of the giant fields are offshore with 22% of the reserves, 11 fields are in east Texas with 24% of the reserves, and 1 field is in Florida with 1% of the reserves. In 106 of the giant fields the primary producing interval is Cenozoic with 65% of the reserves, and in 28 giant fields the producing interval is Mesozoic with 35% of the reserves. The primary producing interval is Mesozoic with 35% of the reserves. The primary producing interval in 124 giant fields consists of clastics with 91% of the reserves, in 7 fields the primary lithology is carbonates with 6% of the reserves, and in 3 giant fields the lithology is mixed clastics and carbonates. A total of 127 fields are in structural traps with all of the reserves, 4 fields are stratigraphic traps (3%) with 18% of the reserves, and 3 fields are combination traps with 1% of the reserves. Over 50 of the giant oil fields in structural traps are salt domes. The most prevalent types of giant fields in the Gulf Coastal area are onshore structural traps with Cenozoic clastics as the primary producing intervals.

  20. (Giant) Proximity Effects in high-Tc superlattices

    NASA Astrophysics Data System (ADS)

    Bozovic, Ivan

    2006-03-01

    Molecular beam epitaxy enables one to synthesize HTS thin films with rms surface roughness in the range 0.2-0.5 nm, much less than the unit cell height (1-2 nm).^1 One can also make atomically smooth multilayers and superlattices in which HTS or spacer layers can be just one unit cell thick if so desired. A detailed study of transport properties of such heterostructures has already revealed some unexpected findings.^2 In junctions where the barrier is made out of underdoped cuprate with a reduced critical temperature Tc, we observe the Giant Proximity Effect: supercurrent runs through very thick barrier layers even at temperature well above Tc (contrary to what is expected from the standard theory).^ Atomic smoothness of films and multilayers, excellent device uniformity, and reversible modulation of barrier properties by oxygen intake provided solid evidence against experimental artifacts such as pinholes and micro-shorts. Hence, the effect is real and intrinsic, and it defies the conventional explanation. Interpretation and significance of our experimental results will be discussed in the context of theoretical concepts such as the pseudogap, midgap states, electronic inhomogeneity, preformed pairs, and possibly resonant pair tunneling. The work at BNL is done in collaboration with G. Logvenov, V. Butko, A. Gozar and A. Bollinger. ^1 I. Bozovic et al., Phys. Rev. Lett. 89, 107001 (2002); P. Abbamonte et al., Science 297, 581 (2002). ^2 I. Bozovic et al., Nature 421, 873 (2003); Phys. Rev. Lett. 93, 157002 (2004).

  1. Giant moving vortex mass in thick magnetic nanodots

    PubMed Central

    Guslienko, K. Y.; Kakazei, G. N.; Ding, J.; Liu, X. M.; Adeyeye, A. O.

    2015-01-01

    Magnetic vortex is one of the simplest topologically non-trivial textures in condensed matter physics. It is the ground state of submicron magnetic elements (dots) of different shapes: cylindrical, square etc. So far, the vast majority of the vortex dynamics studies were focused on thin dots with thickness 5–50 nm and only uniform across the thickness vortex excitation modes were observed. Here we explore the fundamental vortex mode in relatively thick (50–100 nm) dots using broadband ferromagnetic resonance and show that dimensionality increase leads to qualitatively new excitation spectra. We demonstrate that the fundamental mode frequency cannot be explained without introducing a giant vortex mass, which is a result of the vortex distortion due to interaction with spin waves. The vortex mass depends on the system geometry and is non-local because of important role of the dipolar interaction. The mass is rather small for thin dots. However, its importance increases drastically with the dot thickness increasing. PMID:26355430

  2. A tetranucleotide repeat (D4S1652) is linked to facioscapulohumeral dystrophy and shows no linkage disequilibrium with the disease

    SciTech Connect

    Mathews, K.D.; Bailey, H.L.; Mills, K.A.

    1994-09-01

    Facioscapulohumeral dystrophy (FSHD) is an autosomal dominant dystrophy which is associated with a deletion in a subtelomeric repeat element on 4q35. The gene has not yet been identified. The probe detecting this deletion (D4F104S1) is not chromosome 4-specific, and at least one large family has been identified which is not linked to chromosome 4. Thus, persymptomatic/prenatal diagnosis can only be provided to families that are proven to be chromosome 4-linked or where a new mutation is demonstrated. The markers available to demonstrate linkage to chromosome 4, D4S139, D4S163, and D4F35S1, are VNTRs. We have used D4S1652, a tetranucleotide repeat recently identified by the Cooperative Human Linkage Center, in our FSHD families. We found it is completely linked to the 4q35 VNTRs and to the disease phenotype. Physical mapping, using radiation hybrids and somatic cell hybrids, places D4S1652 between D4S139, an interval of approximately 1 Mb. We have used D4S1652 to look for linkage disequilibrium in our FSHD patient population. This result is of interest because of our hypothesis that the deletion in the subtelomeric repeat element alters transcription of a more proximal gene through a position effect. Previously available markers have been unsatisfactory for this experiment because of difficulty comparing numerous VNTR alleles across families. We observed 4, easily distinguished, D4S1652 alleles in our families. We studied 14 chromosomes associated with disease phenotype and 55 chromosomes from nontransmitting parents. We found no evidence for linkage disequilibrium ({chi}{sup 2}=1.313, nonsignificant). This result will need confirmation with a larger patient population, but is consistent with the clinical observation that there is a high rate of a new mutation in this disorder.

  3. Regional flexibility in the S4-S5 linker regulates hERG channel closed-state stabilization.

    PubMed

    Hull, Christina M; Sokolov, Stanislav; Van Slyke, Aaron C; Claydon, Tom W

    2014-10-01

    hERG K(+) channel function is vital for normal cardiac rhythm, yet the mechanisms underlying the unique biophysical characteristics of the channel, such as slow activation and deactivation gating, are incompletely understood. The S4-S5 linker is thought to transduce voltage sensor movement to opening of the pore gate, but may also integrate signals from cytoplasmic domains. Previously, we showed that substitutions of G546 within the S4-S5 linker destabilize the closed state of the channel. Here, we present results of a glycine-scan in the background of 546L. We demonstrate site-specific restoration of WT-like activation which suggests that flexibility in the N-terminal portion of the S4-S5 linker is critical for the voltage dependence of hERG channel activation. In addition, we show that the voltage dependence of deactivation, which was recently shown to be left-shifted from that of activation due to voltage sensor mode-shift, is also modulated by the S4-S5 linker. The G546L mutation greatly attenuated the coupling of voltage sensor mode-shift to the pore gate without altering the mode-shift itself. Indeed, all of the S4-S5 linker mutations tested similarly reduced coupling of the mode-shift to the pore gate. These data demonstrate a key role for S4-S5 linker in the unique activation and deactivation gating of hERG channels. Furthermore, uncoupling of the mode-shift to the pore by S4-S5 linker mutations parallels the effects of mutations in the N-terminus suggestive of functional interactions between the two regions.

  4. Building the giant planet cores by convergent migration of pebble-accreting embryos

    NASA Astrophysics Data System (ADS)

    Chrenko, Ondrej; Broz, Miroslav

    2016-10-01

    An explanation of the accretion buildup of giant planet cores on rather short (~Myr) time scales remains a long-standing challenge for scenarios of planetary system formation. One of the recently proposed processes that can take part during this evolutionary stage is the convergent Type I migration of Earth-sized embryos towards the zero-torque radius, occurring at an opacity transition within the dusty-gaseous protoplanetary disk (e.g. Pierens et al. 2013). Inconveniently, simulations show that such groups of embryos do not merge easily because they often get locked in mutual mean-motion resonances and consequently form an inward-migrating convoy.We revise this possibility of merging embryos while taking into account their ongoing growth by pebble accretion. Our aim is to check whether the rapid changes of masses combined with the migration of embryos through the feeding zone can break the resonant chain and allow for the giant planet core formation.The environment of the protoplanetary disk is modeled with the 2D FARGO code (Masset 2000), which we modified in order to perform non-isothermal hydrodynamic simulations, assuming flux-limited radiative diffusion (Levermore & Pomraning 1981). The embedded massive bodies are evolved simultaneously in 3D using the hybrid Wisdom-Holman/Gauss-Radau integrator from the Rebound package (Rein & Spiegel 2015). A semi-analytic method is used to evolve the masses of embryos by pebble accretion (e.g. Levison et al. 2015).

  5. Viral metagenomics: are we missing the giants?

    PubMed

    Halary, S; Temmam, S; Raoult, D; Desnues, C

    2016-06-01

    Amoeba-infecting giant viruses are recently discovered viruses that have been isolated from diverse environments all around the world. In parallel to isolation efforts, metagenomics confirmed their worldwide distribution from a broad range of environmental and host-associated samples, including humans, depicting them as a major component of eukaryotic viruses in nature and a possible resident of the human/animal virome whose role is still unclear. Nevertheless, metagenomics data about amoeba-infecting giant viruses still remain scarce, mainly because of methodological limitations. Efforts should be pursued both at the metagenomic sample preparation level and on in silico analyses to better understand their roles in the environment and in human/animal health and disease. PMID:26851442

  6. The treatment of giant rhinophyma - Case Report.

    PubMed

    Popa, D; Osman, Georgeta; Parvanescu, H; Ciurea, Raluca; Ciurea, M

    2012-01-01

    The aim of the article is to present an update on the pathophysiology, clinical features and treatment of rhinophyma. A 56 years old patient, living in urban area, presented with a giant rhinophyma which caused him not only upper airways obstruction and difficulty in eating, but also aesthetic and psycho-social disadvantages.The treatment of the patient was a surgical intervention consisting in removal of the nasal tumor and split-thickness skin grafting of the defect. The aesthetic result after surgical intervention was very good, there were no postoperative complications or recurrences.Rhinophyma represents the most advanced form of acne rosacea. The diagnosis is easy to establish based on the clinical features of the disease. In advanced forms of rhinophyma, when the tumor is giant, the main method of treatment is surgery. PMID:24778841

  7. Giant radio galaxies and cosmic web

    NASA Astrophysics Data System (ADS)

    Heinämäki, Pekka

    2016-10-01

    Giant radio galaxies create the welldistinguishable class of sources.These sources are characterized with edge-brightened radio lobes withhighly collimated radio jets and large linear sizes which make themthe largest individual structures in the Universe. They are also knownto be hosted by elliptical/disturbed host galaxies and avoid clustersand high galaxy density regions. Because of GRG, large linear sizeslobes extend well beyond the interstellar media and host galaxyhalo the evolution of the radio lobes may depend on interactionwith this environment. Using our method to extract filamentarystructure of the galaxies in our local universe we study whetherradio lobe properties in some giant radio galaxies are determinedon an interaction of this filament ambient.

  8. Giant viruses of the Kutch Desert.

    PubMed

    Kerepesi, Csaba; Grolmusz, Vince

    2016-03-01

    The Kutch Desert (Great Rann of Kutch, Gujarat, India) is a unique ecosystem: in the larger part of the year it is a hot, salty desert that is flooded regularly in the Indian monsoon season. In the dry season, the crystallized salt deposits form the "white desert" in large regions. The first metagenomic analysis of the soil samples of Kutch was published in 2013, and the data were deposited in the NCBI Sequence Read Archive. At the same time, the sequences were analyzed phylogenetically for prokaryotes, especially for bacteria. In the present work, we identified DNA sequences of recently discovered giant viruses in the soil samples from the Kutch Desert. Since most giant viruses have been discovered in biofilms in industrial cooling towers, ocean water, and freshwater ponds, we were surprised to find their DNA sequences in soil samples from a seasonally very hot and arid, salty environment.

  9. Thermal escape from extrasolar giant planets

    PubMed Central

    Koskinen, Tommi T.; Lavvas, Panayotis; Harris, Matthew J.; Yelle, Roger V.

    2014-01-01

    The detection of hot atomic hydrogen and heavy atoms and ions at high altitudes around close-in extrasolar giant planets (EGPs) such as HD209458b implies that these planets have hot and rapidly escaping atmospheres that extend to several planetary radii. These characteristics, however, cannot be generalized to all close-in EGPs. The thermal escape mechanism and mass loss rate from EGPs depend on a complex interplay between photochemistry and radiative transfer driven by the stellar UV radiation. In this study, we explore how these processes change under different levels of irradiation on giant planets with different characteristics. We confirm that there are two distinct regimes of thermal escape from EGPs, and that the transition between these regimes is relatively sharp. Our results have implications for thermal mass loss rates from different EGPs that we discuss in the context of currently known planets and the detectability of their upper atmospheres. PMID:24664923

  10. Giant nonlocal lossless permittivity at optical frequencies.

    PubMed

    Goncharenko, A V; Nazarov, V U

    2015-08-10

    We show how to achieve a giant permittivity combined with negligible losses in both the visible and the near-IR for composites made of alternating layers of plasmonic and gain materials as the electric field is directed normally to the layers. The effects of nonlocality are taken into account that makes the method quite realistic. Solving the dispersion equation for eigenmodes of an infinite layered composite, we show that both propagating and nonpropagating modes can be excited, that leads to the realization of a giant nonlocal permittivity. Both phase and group velocities for the propagating eigenmode have been calculated showing that slow light can be achieved in the system under study. The results obtained open new possibilities for designing nanolaser, slow-light, superresolution imaging devices, etc. PMID:26367898

  11. Thermal escape from extrasolar giant planets.

    PubMed

    Koskinen, Tommi T; Lavvas, Panayotis; Harris, Matthew J; Yelle, Roger V

    2014-04-28

    The detection of hot atomic hydrogen and heavy atoms and ions at high altitudes around close-in extrasolar giant planets (EGPs) such as HD209458b implies that these planets have hot and rapidly escaping atmospheres that extend to several planetary radii. These characteristics, however, cannot be generalized to all close-in EGPs. The thermal escape mechanism and mass loss rate from EGPs depend on a complex interplay between photochemistry and radiative transfer driven by the stellar UV radiation. In this study, we explore how these processes change under different levels of irradiation on giant planets with different characteristics. We confirm that there are two distinct regimes of thermal escape from EGPs, and that the transition between these regimes is relatively sharp. Our results have implications for thermal mass loss rates from different EGPs that we discuss in the context of currently known planets and the detectability of their upper atmospheres. PMID:24664923

  12. Giant viruses of the Kutch Desert.

    PubMed

    Kerepesi, Csaba; Grolmusz, Vince

    2016-03-01

    The Kutch Desert (Great Rann of Kutch, Gujarat, India) is a unique ecosystem: in the larger part of the year it is a hot, salty desert that is flooded regularly in the Indian monsoon season. In the dry season, the crystallized salt deposits form the "white desert" in large regions. The first metagenomic analysis of the soil samples of Kutch was published in 2013, and the data were deposited in the NCBI Sequence Read Archive. At the same time, the sequences were analyzed phylogenetically for prokaryotes, especially for bacteria. In the present work, we identified DNA sequences of recently discovered giant viruses in the soil samples from the Kutch Desert. Since most giant viruses have been discovered in biofilms in industrial cooling towers, ocean water, and freshwater ponds, we were surprised to find their DNA sequences in soil samples from a seasonally very hot and arid, salty environment. PMID:26666442

  13. Effects of a giant impact on Uranus

    NASA Technical Reports Server (NTRS)

    Slattery, W. L.; Benz, W.; Cameron, A. G. W.

    1991-01-01

    The effects of a giant impact on Uranus with respect to the axis tilt of Uranus and its satellites are discussed. The simulations of possible giant impacts were carried out using Cray supercomputers. The technique used is called smooth particle hydrodynamics (SPH). In this technique, the material in the proto-Uranus planet and in the impactor is divided into a large number of particles which can overlap one another so that local averages over these particles determine density and pressure in the problem, and the particles themselves have their own temperatures and internal energies. During the course of the simulation, these particles move around under the influence of the forces acting on them: gravity and pressure gradients. The results of model simulations are presented.

  14. Thermal escape from extrasolar giant planets.

    PubMed

    Koskinen, Tommi T; Lavvas, Panayotis; Harris, Matthew J; Yelle, Roger V

    2014-04-28

    The detection of hot atomic hydrogen and heavy atoms and ions at high altitudes around close-in extrasolar giant planets (EGPs) such as HD209458b implies that these planets have hot and rapidly escaping atmospheres that extend to several planetary radii. These characteristics, however, cannot be generalized to all close-in EGPs. The thermal escape mechanism and mass loss rate from EGPs depend on a complex interplay between photochemistry and radiative transfer driven by the stellar UV radiation. In this study, we explore how these processes change under different levels of irradiation on giant planets with different characteristics. We confirm that there are two distinct regimes of thermal escape from EGPs, and that the transition between these regimes is relatively sharp. Our results have implications for thermal mass loss rates from different EGPs that we discuss in the context of currently known planets and the detectability of their upper atmospheres.

  15. Part Design of Giant Magnetostrictive Actuator

    NASA Astrophysics Data System (ADS)

    Sun, Zhonglei; Zhao, Meiying; Yin, Zidong

    The key parts of giant magnetostrictive actuator, flexure hinge and pre-stress disc spring, were designed and analyzed. Rotation stiffness and strength characteristics of flexure hinge were analyzed, calculation equations for rotation stiffness and strength were established as well. Fatigue characteristic was also analyzed as flexure hinge usually worked under high frequency situation. In order to improve output efficiency of the giant magnetostrictive actuator and reduce energy loss, an ideal spring force-deformation curve, whose shape was bilinear broken line, of the pre- stress disc spring was put forward, and a disc spring was designed by configuring its geometric parameters to make its spring force-deformation curve was approximate to the ideal spring force-deformation curve.

  16. Giant pleomorphic adenoma of the parotid gland.

    PubMed

    Takahama, Ademar; da Cruz Perez, Danyel Elias; Magrin, José; de Almeida, Oslei Paes; Kowalski, Luiz Paulo

    2008-01-01

    Pleomorphic adenoma is the most common type of all benign and malignant salivary gland tumors, involving more frequently the parotid gland. It is a benign tumor with a slow and continuous growth that without treatment can reach an enormous size. We present a case of a giant pleomorphic adenoma in a 78-year-old man with a history of more than 30 years of a growing lesion in the parotid gland. Clinical examination revealed a giant mass on the right side of the face, however without any sign of facial nerve damage. The tumor was completely resected by total parotidectomy and preservation of the facial nerve. Macroscopically, the tumor measured 28 cm and weighed 4.0 Kg. On the histological examination there was a predominance of epithelial and myoepithelial cells in a hyaline and myxoid stroma. It was not found any area of malignant transformation. In the post-operatory the aesthetic and functional results were excellent.

  17. Giant colonic diverticulum: radiographic and MDCT characteristics.

    PubMed

    Zeina, Abdel-Rauf; Mahamid, Ahmad; Nachtigal, Alicia; Ashkenazi, Itamar; Shapira-Rootman, Mika

    2015-12-01

    Giant colonic diverticulum (GCD), defined as a diverticulum larger than 4 cm, is a rare entity that is generally a manifestation of colonic diverticular disease. Because of its rarity and its variable and non-specific presentation, the diagnosis of GCD depends mainly on imaging findings. Knowledge of the spectrum of radiographic and CT features of the GCD is important in making the correct diagnosis and potentially preventing complications. This review focuses on imaging findings characteristic of GCD as well as its complications and radiographic mimics. Teaching points • Giant colonic diverticulum is a rare complication of diverticulosis.• The most common symptom is abdominal pain presenting in approximately 70 % of patients.• Diagnosis is based on imaging findings with plain abdominal radiographs and MDCT.• Treatment consists of en bloc resection of the diverticulum and affected adjacent colon.

  18. Isolated giant molluscum contagiosum mimicking epidermoid cyst.

    PubMed

    Uzuncakmak, Tugba K; Kuru, Burce C; Zemheri, Ebru I; Zindanci, Ilkin; Turkoglu, Zafer; Kavala, Mukaddes

    2016-07-01

    Molluscum contagiosum is a benign cutaneous viral infection which is caused by double- stranded DNA poxvirus. It affects mainly children and young adults and usually presents with single or multiple umblicated papules or nodules on face, arms, legs and anogenital regions. It may present in atypical size and clinical appearance in patients with altered or impaired immunity and rarely in immuncompetent patients. Herein we present an immuncompetent young adult patient with isolated giant molluscum contagiosum, which was mimicking epidermoid cyst clinically. PMID:27648389

  19. Asteroseismic age determination for dwarfs and giants

    NASA Astrophysics Data System (ADS)

    Silva Aguirre, V.; Serenelli, A. M.

    2016-09-01

    Asteroseismology can make a substantial contribution to our understanding of the formation history and evolution of our Galaxy by providing precisely determined stellar properties for thousands of stars in different regions of the Milky Way. We present here the different sets of observables used in determining asteroseismic stellar properties, the typical level of precision obtained, the current status of results for ages of dwarfs and giants, and the improvements than can be expected in the near future in the context of Galactic archaeology.

  20. Isolated giant molluscum contagiosum mimicking epidermoid cyst

    PubMed Central

    Uzuncakmak, Tugba K.; Kuru, Burce C.; Zemheri, Ebru I.; Zindanci, Ilkin; Turkoglu, Zafer; Kavala, Mukaddes

    2016-01-01

    Molluscum contagiosum is a benign cutaneous viral infection which is caused by double- stranded DNA poxvirus. It affects mainly children and young adults and usually presents with single or multiple umblicated papules or nodules on face, arms, legs and anogenital regions. It may present in atypical size and clinical appearance in patients with altered or impaired immunity and rarely in immuncompetent patients. Herein we present an immuncompetent young adult patient with isolated giant molluscum contagiosum, which was mimicking epidermoid cyst clinically. PMID:27648389

  1. Isolated giant molluscum contagiosum mimicking epidermoid cyst

    PubMed Central

    Uzuncakmak, Tugba K.; Kuru, Burce C.; Zemheri, Ebru I.; Zindanci, Ilkin; Turkoglu, Zafer; Kavala, Mukaddes

    2016-01-01

    Molluscum contagiosum is a benign cutaneous viral infection which is caused by double- stranded DNA poxvirus. It affects mainly children and young adults and usually presents with single or multiple umblicated papules or nodules on face, arms, legs and anogenital regions. It may present in atypical size and clinical appearance in patients with altered or impaired immunity and rarely in immuncompetent patients. Herein we present an immuncompetent young adult patient with isolated giant molluscum contagiosum, which was mimicking epidermoid cyst clinically.

  2. Giant Retroperitoneal Lipoma in an Infant

    PubMed Central

    2014-01-01

    Lipomas can occur almost anywhere in the body, but retroperitoneal lipomas are extremely rare. They are slowly growing benign tumors and can attain an enormous size due to silent course of the disease. Total excision of the mass is the treatment of choice and is curative for benign retroperitoneal lipomas. We treated an 11-month-old female patient with giant retroperitoneal lipomas by surgical excision. Histopathology confirmed it as fibrolipoma. PMID:25374800

  3. Bilateral giant abdominoscrotal hydroceles complicated by appendicitis.

    PubMed

    Yarram, Sai G; Dipietro, Michael A; Graziano, Kathleen; Mychaliska, George B; Strouse, Peter J

    2005-12-01

    Abdominoscrotal hydrocele is a rare entity, with fewer than 100 cases reported in children. Bilateral abdominoscrotal hydroceles are even less common, with 14 cases reported in children. Various complications of abdominoscrotal hydrocele have been reported in the literature. We present a 4-month-old boy with bilateral giant abdominoscrotal hydroceles who developed appendicitis apparently because of obstruction from the right hydrocele. We discuss the various imaging modalities used to establish the diagnosis and plan the operative approach.

  4. Giant gastric trichobezoar in a young female.

    PubMed

    Ibuowo, Abdulrazaq Akin; Saad, Anwar; Okonkwo, Thomas

    2008-12-01

    Bezoars are concretions of undigested matter in the gastrointestinal tract (GIT), most commonly in the stomach. The main predispositions to bezoar formation are, altered GIT anatomy or disordered GIT motility/physiology. Clinically, bezoars are classified according to their predominant component. Trichobezoars (composed mainly of hair) as a clinical entity are almost always associated with an underlying psychiatric disorder. We present below a case of giant gastric trichobezoar in a young female which was treated by gastrostomy and excision of the mass.

  5. [Giant retroperitoneal mesenteric cyst presenting as dyspepsia].

    PubMed

    Rosón Rodríguez, Pedro J; Asensio, Antonio Del Fresno; Quintero Barranco, Belén

    2010-01-01

    Dyspepsia is a frequent cause of referral to gastroenterology units. After appropriate investigations, many patients receive a diagnosis of functional disorders, although dyspepsia can have an organic basis. We present the case of a woman with typical symptoms of dyspepsia, which were initially mild. After appropriate investigations, the patient was diagnosed with a giant retroperitoneal tumor. We discuss the diagnostic approach to this entity and review the literature on the topic.

  6. Giant myoepithelioma of the soft palate.

    PubMed

    Oktay, Murat; Yaman, Huseyin; Belada, Abdullah; Besir, Fahri Halit; Guclu, Ender

    2014-01-01

    Myoepitheliomas are benign salivary gland tumors and account for less than 1% of all salivary gland tumors. They are usually located in the parotid gland. The soft palate is very rare affected site. The differential diagnosis of myoepitheliomas should include reactive and neoplastic lesions. The treatment of myoepitheliomas is complete removal of the tumor. Herein, we report a case with giant myoepithelioma of the soft palate, reviewing the related literature.

  7. Evolution of Chromospheric Activity: M67 Red Giants

    NASA Astrophysics Data System (ADS)

    Dupree, A. K.; Whitney, B. A.; Pasquini, L.

    1999-08-01

    Echelle spectra of the Ca II H- and K-line region (λ3950) of 15 red giant stars in the open cluster M67 reveal atmospheric dynamics and determine chromospheric radiative losses in order to assess chromospheric heating requirements and to follow the evolution of chromospheric activity. M67 red giants in conjunction with giants in younger clusters create a continuous group of red giants in the color-magnitude diagram, with 0.1<=(B-V)<=1.65 along the red giant branch. M67 contains the more evolved clump giants as well. Asymmetric line emission cores, indicative of outflowing material, are found in a majority of the M67 giants on the red giant branch and occur over the complete sample, from MV=-0.8 to MV=1.9, suggesting that outward mass motions are well established at these luminosities. Radiative losses, as measured by emission strengths from Ca II, decrease smoothly with decreasing stellar effective temperature in M67 and connect well to a combined sample of warmer cluster giants (NGC 2477, IC 4756, and the Hyades) with M<=3 Msolar studied by Beasley & Cram. Stellar effective temperature predominantly determines the level of chromospheric Ca II losses for giants with M<=3 Msolar. No evidence is found for a sharp decline in the flux of Ca II predicted by the Rutten & Pylyser magnetic model for chromospheric heating. However, emission in field giants (which tend to be younger) suggests that sharp declines in surface flux with decreasing effective temperature characteristic of pure magnetic activity occur for ion species more highly excited than Ca II. Although acoustic models for chromospheric heating apparently agree with the measured Ca II flux levels for the coolest giants, additional heating processes must be present in warmer giants and clump stars. Clump giants exhibit Ca II fluxes consistent with stars of similar colors on the red giant branch, suggesting a renaissance in chromospheric heating occurs after evolution beyond the red giant branch. Chromospheric

  8. Molecular characterization and analysis of high-level multidrug-resistance of Shigella flexneri serotype 4s strains from China

    PubMed Central

    Yang, Chaojie; Li, Peng; Zhang, Xiujuan; Ma, Qiuxia; Cui, Xianyan; Li, Hao; Liu, Hongbo; Wang, Jian; Xie, Jing; Wu, Fuli; Sheng, Chunyu; Du, Xinying; Qi, Lihua; Su, Wenli; Jia, Leili; Xu, Xuebin; Zhao, Jiayong; Xia, Shengli; Zhou, Na; Ma, Hui; Qiu, Shaofu; Song, Hongbin

    2016-01-01

    To conduct the first comprehensive analysis of Shigella flexneri serotype 4s, a novel serotype found in 2010, we identified 24 serotype 4s isolates from 1973 shigellosis cases in China (2002–2014). The isolates were characterized by single nucleotide polymorphism (SNP) phylogenetic analysis, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) to determine their genetic relatedness, and analysed further for their antimicrobial susceptibilities and antimicrobial resistance determinants. The PFGE and SNP phylogenetic analyses suggest that S. flexneri serotype 4s strains are derived from multiple serotypes, including two predominant serotypes in China: serotype X variant and serotype II. Three new sequence types were identified by MLST. All isolates were resistant to ticarcillin, ampicillin and tetracycline, with high-level resistance to third-generation cephalosporins. Notably, all the isolates were multidrug resistant (MDR), with the highest levels of resistance observed for eight antimicrobials classes. Most isolates contain various antimicrobial resistance determinants. In conclusion, we found that serotype 4s isolates have multiple evolutionary sources, diverse biochemical characteristics and genomes, and highly prevalent multidrug resistance and antimicrobial-resistant determinants. With few clinical treatment options, continuous monitoring and timely intervention against this emerging MDR serotype is essential. The possibility that serotype 4s will become the next predominant serotype exists. PMID:27374009

  9. Molecular characterization and analysis of high-level multidrug-resistance of Shigella flexneri serotype 4s strains from China.

    PubMed

    Yang, Chaojie; Li, Peng; Zhang, Xiujuan; Ma, Qiuxia; Cui, Xianyan; Li, Hao; Liu, Hongbo; Wang, Jian; Xie, Jing; Wu, Fuli; Sheng, Chunyu; Du, Xinying; Qi, Lihua; Su, Wenli; Jia, Leili; Xu, Xuebin; Zhao, Jiayong; Xia, Shengli; Zhou, Na; Ma, Hui; Qiu, Shaofu; Song, Hongbin

    2016-01-01

    To conduct the first comprehensive analysis of Shigella flexneri serotype 4s, a novel serotype found in 2010, we identified 24 serotype 4s isolates from 1973 shigellosis cases in China (2002-2014). The isolates were characterized by single nucleotide polymorphism (SNP) phylogenetic analysis, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) to determine their genetic relatedness, and analysed further for their antimicrobial susceptibilities and antimicrobial resistance determinants. The PFGE and SNP phylogenetic analyses suggest that S. flexneri serotype 4s strains are derived from multiple serotypes, including two predominant serotypes in China: serotype X variant and serotype II. Three new sequence types were identified by MLST. All isolates were resistant to ticarcillin, ampicillin and tetracycline, with high-level resistance to third-generation cephalosporins. Notably, all the isolates were multidrug resistant (MDR), with the highest levels of resistance observed for eight antimicrobials classes. Most isolates contain various antimicrobial resistance determinants. In conclusion, we found that serotype 4s isolates have multiple evolutionary sources, diverse biochemical characteristics and genomes, and highly prevalent multidrug resistance and antimicrobial-resistant determinants. With few clinical treatment options, continuous monitoring and timely intervention against this emerging MDR serotype is essential. The possibility that serotype 4s will become the next predominant serotype exists. PMID:27374009

  10. A new strategy for introducing photoactivatable 4-thiouridine ((4S)U) into specific positions in a long RNA molecule.

    PubMed

    Yu, Y T; Steitz, J A

    1997-07-01

    We describe a new protocol, which does not require (4S)UpG, for introducing (4S)U into specific sites in a pre-mRNA substrate. A 5'-half and a full-length RNA are first synthesized by phage RNA polymerase. p(4S)Up, which is derived from (4S)UpU and can therefore be 32P-labeled, is then ligated to the 3' end of the 5'-half RNA with T4 RNA ligase. The 3' phosphate of the ligated product is removed subsequently by CIP (calf intestinal alkaline phosphatase) to produce a 3'-OH group. The 3'-half RNA with a 5' phosphate is produced by site-specific RNase H cleavage of the full-length pre-mRNA directed by a 2'-O-methyl RNA-DNA chimera. The two half RNAs are then aligned with a bridging oligonucleotide and ligated with T4 DNA ligase. Our results show that 32P-p(4S)Up ligation to the 3' end of the 5'-half RNA is comparable to 32P-pCp ligation. Also, the efficiency of the bridging oligonucleotide-mediated two-piece ligation is quite high, approximately 30-50%. This strategy has been applied to the P120 pre-mRNA containing an AT-AC intron, but should be applicable to many other RNAs. PMID:9214662

  11. Two cases of giant serpentine aneurysm.

    PubMed

    Kumabe, T; Kaneko, U; Ishibashi, T; Kaneko, K; Uchigasaki, S

    1990-06-01

    Giant serpentine aneurysm (GSA) is an entity defined on radiological and pathological grounds as a giant, partially thrombosed aneurysm containing tortuous vascular channels. We have had the opportunity to study two patients with GSAs, which has allowed for a complete comparative anatomical and radiological study. This report emphasizes the etiology of the GSAs. Twenty-two patients with GSAs have been reported in the literature, of which pathological studies were done in 10. In most of these, the aneurysm was found to be filled with an organized thrombus, but in our patients the aneurysm was filled with relatively new clot. The aneurysm enlarged and a change in the tortuous vascular channel was observed over a period of 1 year in the first patient, whereas a globoid aneurysm developed into a GSA in the brief period of just 2 weeks in the second patient. This rapid transformation of a globoid aneurysm into a GSA is of particular interest when the etiology of GSAs is considered. Our patients therefore shed some interesting light on the possible pathophysiology of GSAs. That is, the bloodstream may change dynamically in a giant aneurysm and may become a serpentine channel under conditions that lead to a "Coanda effect." PMID:2362659

  12. Giant Cell Tumor of Bone - An Overview

    PubMed Central

    Sobti, Anshul; Agrawal, Pranshu; Agarwala, Sanjay; Agarwal, Manish

    2016-01-01

    Giant Cell tumors (GCT) are benign tumors with potential for aggressive behavior and capacity to metastasize. Although rarely lethal, benign bone tumors may be associated with a substantial disturbance of the local bony architecture that can be particularly troublesome in peri-articular locations. Its histogenesis remains unclear. It is characterized by a proliferation of mononuclear stromal cells and the presence of many multi- nucleated giant cells with homogenous distribution. There is no widely held consensus regarding the ideal treatment method selection. There are advocates of varying surgical techniques ranging from intra-lesional curettage to wide resection. As most giant cell tumors are benign and are located near a joint in young adults, several authors favor an intralesional approach that preserves anatomy of bone in lieu of resection. Although GCT is classified as a benign lesion, few patients develop progressive lung metastases with poor outcomes. Treatment is mainly surgical. Options of chemotherapy and radiotherapy are reserved for selected cases. Recent advances in the understanding of pathogenesis are essential to develop new treatments for this locally destructive primary bone tumor. PMID:26894211

  13. Observations of Radio Giant Pulses with GAVRT

    NASA Astrophysics Data System (ADS)

    Jones, Glenn

    2011-08-01

    Radio giant pulses provide a unique opportunity to study the pulsar radio emission mechanism in exquisite detail. Previous studies have revealed a wide range of properties and phenomena, including extraordinarily high brightness temperatures, sub-nanosecond emission features, and banded dynamic spectra. New measurements of giant pulse characteristics can help guide and test theoretical emission models. To this end, an extensive observation campaign has begun which will provide more than 500 hours on the Crab with a 34-meter antenna located in California, USA. The observations are being done as part of an educational outreach program called the Goldstone-Apple Valley Radio Telescope (GAVRT). This antenna has a novel wide bandwidth receiver which provides up to 8 GHz of instantaneous bandwidth in the range of 2.5 to 14 GHz. These observations will provide detailed information about the variability, amplitude distribution, and detailed frequency structure of radio giant pulses. In addition, a database of pulses from these observations and others of the Crab pulsar is being created which will simplify multiwavelength correlation analysis.

  14. Fingering convection in red giants revisited

    NASA Astrophysics Data System (ADS)

    Wachlin, F. C.; Vauclair, S.; Althaus, L. G.

    2014-10-01

    Context. Fingering (thermohaline) convection has been invoked for several years as a possible extra-mixing which could occur in red giant stars; it is due to the modification of the chemical composition induced by nuclear reactions in the hydrogen burning zone. Recent studies show, however, that this mixing is not sufficient to account for the needed surface abundances. Aims: A new prescription for fingering convection, based on 3D numerical simulations has recently been proposed. The resulting mixing coefficient is larger than those previously given in the literature. We compute models using this new coefficient and compare them to previous studies. Methods: We used the LPCODE stellar evolution code with a generalized version of the mixing length theory to compute red giant models and we introduce fingering convection using the BGS prescription. Results: The results show that, although the fingering zone now reaches the outer dynamical convective zone, the efficiency of the mixing is not enough to account for the observations. The fingering mixing coefficient should be increased by two orders of magnitude for the needed surface abundances to be reached. Conclusions: We confirm that fingering convection cannot be the mixing process needed to account for surface abundances in red giant branch stars.

  15. A Quick Method to Identify Secular Resonances in Multi-planet Systems with a Binary Companion

    NASA Astrophysics Data System (ADS)

    Pilat-Lohinger, E.; Bazsó, A.; Funk, B.

    2016-11-01

    Gravitational perturbations in multi-planet systems caused by an accompanying star are the subject of this investigation. Our dynamical model is based on the binary star HD 41004 AB where a giant planet orbits HD 41004 A. We modify the orbital parameters of this system and analyze the motion of a hypothetical test planet surrounding HD 41004 A on an interior orbit to the detected giant planet. Our numerical computations indicate perturbations due to mean motion and secular resonances (SRs). The locations of these resonances are usually connected to high eccentricity and highly inclined motion depending strongly on the binary-planet architecture. As the positions of mean motion resonances can easily be determined, the main purpose of this study is to present a new semi-analytical method to determine the location of an SR without huge computational effort.

  16. Giant cell rich osteosarcoma of the mandible with abundant spindle cells and osteoclast-like giant cells mimicking malignancy in giant cell tumor

    PubMed Central

    Sun, Li-Mei; Zhang, Qing-Fu; Tang, Na; Mi, Xiao-Yi; Qiu, Xue-Shan

    2015-01-01

    Giant cell rich osteosarcoma is a relatively unusual histological form of osteosarcoma, common lesion usually presenting in the long bones of the appendicular skeleton. The occurrence in the mandible is exceptional rare. Histologically, this tumor tends to be a highly anaplastic, pleomorphic tumor in which the tumor cells may be: plasmacytoid, fusiform, ovoid, small round cells, clear cells, mono-or multinucleated giant cells, or, spindle cells. Herein, we present a case with the sternum and first thoracic vertebra metastasis from primary giant cell rich osteosarcoma of the mandible in a 28 year-old Chinese female. The tumor was predominantly composed of abundant spindle cells with marked atypia and numerous osteoclast-like giant cells reminiscent of malignancy in giant cell tumor. The unusual histological appearance can pose a great diagnostic challenge. It may be easily misdiagnosed, especially if the specimen is limited or from fine-needle aspiration. PMID:26464744

  17. Cavity- and waveguide-resonators in electron paramagnetic resonance, nuclear magnetic resonance, and magnetic resonance imaging.

    PubMed

    Webb, Andrew

    2014-11-01

    Cavity resonators are widely used in electron paramagnetic resonance, very high field magnetic resonance microimaging and also in high field human imaging. The basic principles and designs of different forms of cavity resonators including rectangular, cylindrical, re-entrant, cavity magnetrons, toroidal cavities and dielectric resonators are reviewed. Applications in EPR and MRI are summarized, and finally the topic of traveling wave MRI using the magnet bore as a waveguide is discussed.

  18. Measurement of the Ratio of Branching Fractions of the Υ(4S) to Charged and Neutral B Mesons

    NASA Astrophysics Data System (ADS)

    Godang, Romulus; Kinoshita, Kay

    2002-04-01

    Using 2.73 fb-1 of CLEO II data taken on the Υ(4S) and 1.43 fb-1 taken at a center of mass energy 60 MeV below the Υ(4S), we measure the ratio of production fractions times the ratio of semileptonic branching fractions, f_+-b_+\\over f_00b0 through the decays barB arrow D^*l^- barν_l, reconstructed using a partial reconstruction method. Assuming that b_+\\over b0 is equal to the lifetime ratio τ_+\\overτ0 and using the world average value of τ_+\\overτ_0, the ratio of branching fractions of the Υ(4S) to charged and neutral B mesons will be presented.

  19. Tyrosine Residues from the S4-S5 Linker of Kv11.1 Channels Are Critical for Slow Deactivation.

    PubMed

    Ng, Chai-Ann; Gravel, Andrée E; Perry, Matthew D; Arnold, Alexandre A; Marcotte, Isabelle; Vandenberg, Jamie I

    2016-08-12

    Slow deactivation of Kv11.1 channels is critical for its function in the heart. The S4-S5 linker, which joins the voltage sensor and pore domains, plays a critical role in this slow deactivation gating. Here, we use NMR spectroscopy to identify the membrane-bound surface of the S4S5 linker, and we show that two highly conserved tyrosine residues within the KCNH subfamily of channels are membrane-associated. Site-directed mutagenesis and electrophysiological analysis indicates that Tyr-542 interacts with both the pore domain and voltage sensor residues to stabilize activated conformations of the channel, whereas Tyr-545 contributes to the slow kinetics of deactivation by primarily stabilizing the transition state between the activated and closed states. Thus, the two tyrosine residues in the Kv11.1 S4S5 linker play critical but distinct roles in the slow deactivation phenotype, which is a hallmark of Kv11.1 channels.

  20. Three cases giant panda attack on human at Beijing Zoo.

    PubMed

    Zhang, Peixun; Wang, Tianbing; Xiong, Jian; Xue, Feng; Xu, Hailin; Chen, Jianhai; Zhang, Dianying; Fu, Zhongguo; Jiang, Baoguo

    2014-01-01

    Panda is regarded as Chinese national treasure. Most people always thought they were cute and just ate bamboo and had never imagined a panda could be vicious. Giant panda attacks on human are rare. There, we present three cases of giant panda attacks on humans at the Panda House at Beijing Zoo from September 2006 to June 2009 to warn people of the giant panda's potentially dangerous behavior.

  1. Three cases giant panda attack on human at Beijing Zoo

    PubMed Central

    Zhang, Peixun; Wang, Tianbing; Xiong, Jian; Xue, Feng; Xu, Hailin; Chen, Jianhai; Zhang, Dianying; Fu, Zhongguo; Jiang, Baoguo

    2014-01-01

    Panda is regarded as Chinese national treasure. Most people always thought they were cute and just ate bamboo and had never imagined a panda could be vicious. Giant panda attacks on human are rare. There, we present three cases of giant panda attacks on humans at the Panda House at Beijing Zoo from September 2006 to June 2009 to warn people of the giant panda’s potentially dangerous behavior. PMID:25550978

  2. The identification of K giant stars in LAMOST pilot survey

    NASA Astrophysics Data System (ADS)

    Liu, Chao; Yang, Fan; Deng, Licai; Xu, Yan; Cui, Wenyuan; Xue, Xiangxiang; Gao, Shuang; Zhang, Yueyang; Xin, Yu

    2014-01-01

    A support vector machine (SVM) method is applied to select K giant stars directly from the spectral features of LAMOST spectra. The performance of the algorithm is assessed using the MILES library. It shows that the completeness of the K giant stars is 87% with only about 6% dwarf contamination. This allows us to select 18,013 K giant stars at |b|>20° and 38,108 at |b|<20° from LAMOST pilot survey data.

  3. Liquid Water Oceans in Ice Giants

    NASA Technical Reports Server (NTRS)

    Wiktorowicz, Sloane J.; Ingersoll, Andrew P.

    2007-01-01

    Aptly named, ice giants such as Uranus and Neptune contain significant amounts of water. While this water cannot be present near the cloud tops, it must be abundant in the deep interior. We investigate the likelihood of a liquid water ocean existing in the hydrogen-rich region between the cloud tops and deep interior. Starting from an assumed temperature at a given upper tropospheric pressure (the photosphere), we follow a moist adiabat downward. The mixing ratio of water to hydrogen in the gas phase is small in the photosphere and increases with depth. The mixing ratio in the condensed phase is near unity in the photosphere and decreases with depth; this gives two possible outcomes. If at some pressure level the mixing ratio of water in the gas phase is equal to that in the deep interior, then that level is the cloud base. The gas below the cloud base has constant mixing ratio. Alternately, if the mixing ratio of water in the condensed phase reaches that in the deep interior, then the surface of a liquid ocean will occur. Below this ocean surface, the mixing ratio of water will be constant. A cloud base occurs when the photospheric temperature is high. For a family of ice giants with different photospheric temperatures, the cooler ice giants will have warmer cloud bases. For an ice giant with a cool enough photospheric temperature, the cloud base will exist at the critical temperature. For still cooler ice giants, ocean surfaces will result. A high mixing ratio of water in the deep interior favors a liquid ocean. We find that Neptune is both too warm (photospheric temperature too high) and too dry (mixing ratio of water in the deep interior too low) for liquid oceans to exist at present. To have a liquid ocean, Neptune s deep interior water to gas ratio would have to be higher than current models allow, and the density at 19 kbar would have to be approx. equal to 0.8 g/cu cm. Such a high density is inconsistent with gravitational data obtained during the Voyager

  4. A resonant chain of four transiting, sub-Neptune planets.

    PubMed

    Mills, Sean M; Fabrycky, Daniel C; Migaszewski, Cezary; Ford, Eric B; Petigura, Erik; Isaacson, Howard

    2016-05-26

    Surveys have revealed many multi-planet systems containing super-Earths and Neptunes in orbits of a few days to a few months. There is debate whether in situ assembly or inward migration is the dominant mechanism of the formation of such planetary systems. Simulations suggest that migration creates tightly packed systems with planets whose orbital periods may be expressed as ratios of small integers (resonances), often in a many-planet series (chain). In the hundreds of multi-planet systems of sub-Neptunes, more planet pairs are observed near resonances than would generally be expected, but no individual system has hitherto been identified that must have been formed by migration. Proximity to resonance enables the detection of planets perturbing each other. Here we report transit timing variations of the four planets in the Kepler-223 system, model these variations as resonant-angle librations, and compute the long-term stability of the resonant chain. The architecture of Kepler-223 is too finely tuned to have been formed by scattering, and our numerical simulations demonstrate that its properties are natural outcomes of the migration hypothesis. Similar systems could be destabilized by any of several mechanisms, contributing to the observed orbital-period distribution, where many planets are not in resonances. Planetesimal interactions in particular are thought to be responsible for establishing the current orbits of the four giant planets in the Solar System by disrupting a theoretical initial resonant chain similar to that observed in Kepler-223. PMID:27225123

  5. A resonant chain of four transiting, sub-Neptune planets.

    PubMed

    Mills, Sean M; Fabrycky, Daniel C; Migaszewski, Cezary; Ford, Eric B; Petigura, Erik; Isaacson, Howard

    2016-05-11

    Surveys have revealed many multi-planet systems containing super-Earths and Neptunes in orbits of a few days to a few months. There is debate whether in situ assembly or inward migration is the dominant mechanism of the formation of such planetary systems. Simulations suggest that migration creates tightly packed systems with planets whose orbital periods may be expressed as ratios of small integers (resonances), often in a many-planet series (chain). In the hundreds of multi-planet systems of sub-Neptunes, more planet pairs are observed near resonances than would generally be expected, but no individual system has hitherto been identified that must have been formed by migration. Proximity to resonance enables the detection of planets perturbing each other. Here we report transit timing variations of the four planets in the Kepler-223 system, model these variations as resonant-angle librations, and compute the long-term stability of the resonant chain. The architecture of Kepler-223 is too finely tuned to have been formed by scattering, and our numerical simulations demonstrate that its properties are natural outcomes of the migration hypothesis. Similar systems could be destabilized by any of several mechanisms, contributing to the observed orbital-period distribution, where many planets are not in resonances. Planetesimal interactions in particular are thought to be responsible for establishing the current orbits of the four giant planets in the Solar System by disrupting a theoretical initial resonant chain similar to that observed in Kepler-223.

  6. A resonant chain of four transiting, sub-Neptune planets

    NASA Astrophysics Data System (ADS)

    Mills, Sean M.; Fabrycky, Daniel C.; Migaszewski, Cezary; Ford, Eric B.; Petigura, Erik; Isaacson, Howard

    2016-05-01

    Surveys have revealed many multi-planet systems containing super-Earths and Neptunes in orbits of a few days to a few months. There is debate whether in situ assembly or inward migration is the dominant mechanism of the formation of such planetary systems. Simulations suggest that migration creates tightly packed systems with planets whose orbital periods may be expressed as ratios of small integers (resonances), often in a many-planet series (chain). In the hundreds of multi-planet systems of sub-Neptunes, more planet pairs are observed near resonances than would generally be expected, but no individual system has hitherto been identified that must have been formed by migration. Proximity to resonance enables the detection of planets perturbing each other. Here we report transit timing variations of the four planets in the Kepler-223 system, model these variations as resonant-angle librations, and compute the long-term stability of the resonant chain. The architecture of Kepler-223 is too finely tuned to have been formed by scattering, and our numerical simulations demonstrate that its properties are natural outcomes of the migration hypothesis. Similar systems could be destabilized by any of several mechanisms, contributing to the observed orbital-period distribution, where many planets are not in resonances. Planetesimal interactions in particular are thought to be responsible for establishing the current orbits of the four giant planets in the Solar System by disrupting a theoretical initial resonant chain similar to that observed in Kepler-223.

  7. Interaction of local anesthetics with a peptide encompassing the IV/S4-S5 linker of the Na+ channel.

    PubMed

    Fraceto, Leonardo F; Oyama, Sérgio; Nakaie, Clóvis R; Spisni, Alberto; de Paula, Eneida; Pertinhez, Thelma A

    2006-08-20

    The peptide pIV/S4-S5 encompasses the cytoplasmic linker between helices S4-S5 in domain IV of the voltage-gated Na+ channel, residues 1644-1664. The interaction of two local anesthetics (LA), lidocaine and benzocaine, with pIV/S4-S5 has been studied by DOSY, heteronuclear NMR 1H-15N-HSQC spectroscopy and computational methods. DOSY indicates that benzocaine, a neutral ester, exhibits stronger interaction with pIV/S4-S5 than lidocaine, a charged amine-amide. Weighted average chemical shifts, Deltadelta(1H-15N), show that benzocaine affects residues L1653, M1655 and S1656 while lidocaine slightly perturbs residues I1646, L1649 and A1659, L1660, near the N- and C-terminus, respectively. Computational methods confirmed the stability of the benzocaine binding and the existence of two binding sites for lidocaine. Even considering that the approach of studying the peptide in the presence of a co-solvent (TFE/H2O, 30%/70% v/v) has an inherently limited implication, our data strongly support the existence of multiple LA binding sites in the IV/S4-S5 linker, as suggested in the literature. In addition, we consider that LA can bind to the S4-S5 linker with diverse binding modes and strength since this linker is part of the receptor for the "inactivation gate particle". Conditions for devising new functional studies, aiming to better understand Na+ channel functionality as well as the various facets of LA pharmacological activity are proposed in this work.

  8. The S4-S5 linker acts as a signal integrator for HERG K+ channel activation and deactivation gating.

    PubMed

    Ng, Chai Ann; Perry, Matthew D; Tan, Peter S; Hill, Adam P; Kuchel, Philip W; Vandenberg, Jamie I

    2012-01-01

    Human ether-à-go-go-related gene (hERG) K(+) channels have unusual gating kinetics. Characterised by slow activation/deactivation but rapid inactivation/recovery from inactivation, the unique gating kinetics underlie the central role hERG channels play in cardiac repolarisation. The slow activation and deactivation kinetics are regulated in part by the S4-S5 linker, which couples movement of the voltage sensor domain to opening of the activation gate at the distal end of the inner helix of the pore domain. It has also been suggested that cytosolic domains may interact with the S4-S5 linker to regulate activation and deactivation kinetics. Here, we show that the solution structure of a peptide corresponding to the S4-S5 linker of hERG contains an amphipathic helix. The effects of mutations at the majority of residues in the S4-S5 linker of hERG were consistent with the previously identified role in coupling voltage sensor movement to the activation gate. However, mutations to Ser543, Tyr545, Gly546 and Ala548 had more complex phenotypes indicating that these residues are involved in additional interactions. We propose a model in which the S4-S5 linker, in addition to coupling VSD movement to the activation gate, also contributes to interactions that stabilise the closed state and a separate set of interactions that stabilise the open state. The S4-S5 linker therefore acts as a signal integrator and plays a crucial role in the slow deactivation kinetics of the channel.

  9. Observation of B→D(*) π^(+)π^(-)ℓ^(-)ν Decays in e^(+)e^(-) Collisions at the Υ(4S) Resonance.

    PubMed

    Lees, J P; Poireau, V; Tisserand, V; Grauges, E; Palano, A; Eigen, G; Stugu, B; Brown, D N; Kerth, L T; Kolomensky, Yu G; Lee, M J; Lynch, G; Koch, H; Schroeder, T; Hearty, C; Mattison, T S; McKenna, J A; So, R Y; Khan, A; Blinov, V E; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Lankford, A J; Gary, J W; Long, O; Franco Sevilla, M; Hong, T M; Kovalskyi, D; Richman, J D; West, C A; Eisner, A M; Lockman, W S; Panduro Vazquez, W; Schumm, B A; Seiden, A; Chao, D S; Cheng, C H; Echenard, B; Flood, K T; Hitlin, D G; Kim, J; Miyashita, T S; Ongmongkolkul, P; Porter, F C; Röhrken, M; Andreassen, R; Huard, Z; Meadows, B T; Pushpawela, B G; Sokoloff, M D; Sun, L; Ford, W T; Smith, J G; Wagner, S R; Ayad, R; Toki, W H; Spaan, B; Bernard, D; Verderi, M; Playfer, S; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Fioravanti, E; Garzia, I; Luppi, E; Santoro, V; Calcaterra, A; de Sangro, R; Finocchiaro, G; Martellotti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Contri, R; Monge, M R; Passaggio, S; Patrignani, C; Bhuyan, B; Prasad, V; Adametz, A; Uwer, U; Lacker, H M; Mallik, U; Chen, C; Cochran, J; Prell, S; Ahmed, H; Gritsan, A V; Arnaud, N; Davier, M; Derkach, D; Grosdidier, G; Le Diberder, F; Lutz, A M; Malaescu, B; Roudeau, P; Stocchi, A; Wormser, G; Lange, D J; Wright, D M; Coleman, J P; Fry, J R; Gabathuler, E; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; Di Lodovico, F; Sacco, R; Cowan, G; Brown, D N; Davis, C L; Denig, A G; Fritsch, M; Gradl, W; Griessinger, K; Hafner, A; Schubert, K R; Barlow, R J; Lafferty, G D; Cenci, R; Hamilton, B; Jawahery, A; Roberts, D A; Cowan, R; Cheaib, R; Patel, P M; Robertson, S H; Dey, B; Neri, N; Palombo, F; Cremaldi, L; Godang, R; Summers, D J; Simard, M; Taras, P; De Nardo, G; Onorato, G; Sciacca, C; Raven, G; Jessop, C P; LoSecco, J M; Honscheid, K; Kass, R; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simi, G; Simonetto, F; Stroili, R; Akar, S; Ben-Haim, E; Bomben, M; Bonneaud, G R; Briand, H; Calderini, G; Chauveau, J; Leruste, Ph; Marchiori, G; Ocariz, J; Biasini, M; Manoni, E; Rossi, A; Angelini, C; Batignani, G; Bettarini, S; Carpinelli, M; Casarosa, G; Chrzaszcz, M; Forti, F; Giorgi, M A; Lusiani, A; Oberhof, B; Paoloni, E; Rama, M; Rizzo, G; Walsh, J J; Lopes Pegna, D; Olsen, J; Smith, A J S; Anulli, F; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Pilloni, A; Piredda, G; Bünger, C; Dittrich, S; Grünberg, O; Hess, M; Leddig, T; Voß, C; Waldi, R; Adye, T; Olaiya, E O; Wilson, F F; Emery, S; Vasseur, G; Aston, D; Bard, D J; Cartaro, C; Convery, M R; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Ebert, M; Field, R C; Fulsom, B G; Graham, M T; Hast, C; Innes, W R; Kim, P; Leith, D W G S; Luitz, S; Luth, V; MacFarlane, D B; Muller, D R; Neal, H; Pulliam, T; Ratcliff, B N; Roodman, A; Schindler, R H; Snyder, A; Su, D; Sullivan, M K; Va'vra, J; Wisniewski, W J; Wulsin, H W; Purohit, M V; Wilson, J R; Randle-Conde, A; Sekula, S J; Bellis, M; Burchat, P R; Puccio, E M T; Alam, M S; Ernst, J A; Gorodeisky, R; Guttman, N; Peimer, D R; Soffer, A; Spanier, S M; Ritchie, J L; Schwitters, R F; Izen, J M; Lou, X C; Bianchi, F; De Mori, F; Filippi, A; Gamba, D; Lanceri, L; Vitale, L; Martinez-Vidal, F; Oyanguren, A; Albert, J; Banerjee, Sw; Beaulieu, A; Bernlochner, F U; Choi, H H F; King, G J; Kowalewski, R; Lewczuk, M J; Lueck, T; Nugent, I M; Roney, J M; Sobie, R J; Tasneem, N; Gershon, T J; Harrison, P F; Latham, T E; Band, H R; Dasu, S; Pan, Y; Prepost, R; Wu, S L

    2016-01-29

    We report on measurements of the decays of B¯ mesons into the semileptonic final states B¯→D^(*)π^(+)π^(-)ℓ^(-)ν¯, where D^(*) represents a D or D^(*) meson and ℓ^(-) is an electron or a muon. These measurements are based on 471×10^(6) BB ¯ pairs recorded with the BABAR detector at the SLAC asymmetric B factory PEP-II. We determine the branching fraction ratios R_{π^{+}π^{-}}^{(*)}=B(B[over ¯]→D^{(*)}π^{+}π^{-}ℓ^{-}ν[over ¯])/B(B[over ¯]→D^{(*)}ℓ^{-}ν[over ¯]) using events in which the second B meson is fully reconstructed. We find R_{π^{+}π^{-}}=0.067±0.010±0.008 and R_{π^{+}π^{-}}^{*}=0.019±0.005±0.004, where the first uncertainty is statistical and the second is systematic. Based on these results and assuming isospin invariance, we estimate that B[over ¯]→D^{(*)}ππℓ^{-}ν[over ¯] decays, where π denotes either a π^{±} and π^{0} meson, account for up to half the difference between the measured inclusive semileptonic branching fraction to charm hadrons and the corresponding sum of previously measured exclusive branching fractions.

  10. Observation of B→D(*) π^(+)π^(-)ℓ^(-)ν Decays in e^(+)e^(-) Collisions at the Υ(4S) Resonance.

    PubMed

    Lees, J P; Poireau, V; Tisserand, V; Grauges, E; Palano, A; Eigen, G; Stugu, B; Brown, D N; Kerth, L T; Kolomensky, Yu G; Lee, M J; Lynch, G; Koch, H; Schroeder, T; Hearty, C; Mattison, T S; McKenna, J A; So, R Y; Khan, A; Blinov, V E; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Lankford, A J; Gary, J W; Long, O; Franco Sevilla, M; Hong, T M; Kovalskyi, D; Richman, J D; West, C A; Eisner, A M; Lockman, W S; Panduro Vazquez, W; Schumm, B A; Seiden, A; Chao, D S; Cheng, C H; Echenard, B; Flood, K T; Hitlin, D G; Kim, J; Miyashita, T S; Ongmongkolkul, P; Porter, F C; Röhrken, M; Andreassen, R; Huard, Z; Meadows, B T; Pushpawela, B G; Sokoloff, M D; Sun, L; Ford, W T; Smith, J G; Wagner, S R; Ayad, R; Toki, W H; Spaan, B; Bernard, D; Verderi, M; Playfer, S; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Fioravanti, E; Garzia, I; Luppi, E; Santoro, V; Calcaterra, A; de Sangro, R; Finocchiaro, G; Martellotti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Contri, R; Monge, M R; Passaggio, S; Patrignani, C; Bhuyan, B; Prasad, V; Adametz, A; Uwer, U; Lacker, H M; Mallik, U; Chen, C; Cochran, J; Prell, S; Ahmed, H; Gritsan, A V; Arnaud, N; Davier, M; Derkach, D; Grosdidier, G; Le Diberder, F; Lutz, A M; Malaescu, B; Roudeau, P; Stocchi, A; Wormser, G; Lange, D J; Wright, D M; Coleman, J P; Fry, J R; Gabathuler, E; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; Di Lodovico, F; Sacco, R; Cowan, G; Brown, D N; Davis, C L; Denig, A G; Fritsch, M; Gradl, W; Griessinger, K; Hafner, A; Schubert, K R; Barlow, R J; Lafferty, G D; Cenci, R; Hamilton, B; Jawahery, A; Roberts, D A; Cowan, R; Cheaib, R; Patel, P M; Robertson, S H; Dey, B; Neri, N; Palombo, F; Cremaldi, L; Godang, R; Summers, D J; Simard, M; Taras, P; De Nardo, G; Onorato, G; Sciacca, C; Raven, G; Jessop, C P; LoSecco, J M; Honscheid, K; Kass, R; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simi, G; Simonetto, F; Stroili, R; Akar, S; Ben-Haim, E; Bomben, M; Bonneaud, G R; Briand, H; Calderini, G; Chauveau, J; Leruste, Ph; Marchiori, G; Ocariz, J; Biasini, M; Manoni, E; Rossi, A; Angelini, C; Batignani, G; Bettarini, S; Carpinelli, M; Casarosa, G; Chrzaszcz, M; Forti, F; Giorgi, M A; Lusiani, A; Oberhof, B; Paoloni, E; Rama, M; Rizzo, G; Walsh, J J; Lopes Pegna, D; Olsen, J; Smith, A J S; Anulli, F; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Pilloni, A; Piredda, G; Bünger, C; Dittrich, S; Grünberg, O; Hess, M; Leddig, T; Voß, C; Waldi, R; Adye, T; Olaiya, E O; Wilson, F F; Emery, S; Vasseur, G; Aston, D; Bard, D J; Cartaro, C; Convery, M R; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Ebert, M; Field, R C; Fulsom, B G; Graham, M T; Hast, C; Innes, W R; Kim, P; Leith, D W G S; Luitz, S; Luth, V; MacFarlane, D B; Muller, D R; Neal, H; Pulliam, T; Ratcliff, B N; Roodman, A; Schindler, R H; Snyder, A; Su, D; Sullivan, M K; Va'vra, J; Wisniewski, W J; Wulsin, H W; Purohit, M V; Wilson, J R; Randle-Conde, A; Sekula, S J; Bellis, M; Burchat, P R; Puccio, E M T; Alam, M S; Ernst, J A; Gorodeisky, R; Guttman, N; Peimer, D R; Soffer, A; Spanier, S M; Ritchie, J L; Schwitters, R F; Izen, J M; Lou, X C; Bianchi, F; De Mori, F; Filippi, A; Gamba, D; Lanceri, L; Vitale, L; Martinez-Vidal, F; Oyanguren, A; Albert, J; Banerjee, Sw; Beaulieu, A; Bernlochner, F U; Choi, H H F; King, G J; Kowalewski, R; Lewczuk, M J; Lueck, T; Nugent, I M; Roney, J M; Sobie, R J; Tasneem, N; Gershon, T J; Harrison, P F; Latham, T E; Band, H R; Dasu, S; Pan, Y; Prepost, R; Wu, S L

    2016-01-29

    We report on measurements of the decays of B¯ mesons into the semileptonic final states B¯→D^(*)π^(+)π^(-)ℓ^(-)ν¯, where D^(*) represents a D or D^(*) meson and ℓ^(-) is an electron or a muon. These measurements are based on 471×10^(6) BB ¯ pairs recorded with the BABAR detector at the SLAC asymmetric B factory PEP-II. We determine the branching fraction ratios R_{π^{+}π^{-}}^{(*)}=B(B[over ¯]→D^{(*)}π^{+}π^{-}ℓ^{-}ν[over ¯])/B(B[over ¯]→D^{(*)}ℓ^{-}ν[over ¯]) using events in which the second B meson is fully reconstructed. We find R_{π^{+}π^{-}}=0.067±0.010±0.008 and R_{π^{+}π^{-}}^{*}=0.019±0.005±0.004, where the first uncertainty is statistical and the second is systematic. Based on these results and assuming isospin invariance, we estimate that B[over ¯]→D^{(*)}ππℓ^{-}ν[over ¯] decays, where π denotes either a π^{±} and π^{0} meson, account for up to half the difference between the measured inclusive semileptonic branching fraction to charm hadrons and the corresponding sum of previously measured exclusive branching fractions. PMID:26871322

  11. Observation of B ¯ →D(*) π+π-ℓ-ν ¯ Decays in e+e- Collisions at the Υ (4 S ) Resonance

    NASA Astrophysics Data System (ADS)

    Lees, J. P.; Poireau, V.; Tisserand, V.; Grauges, E.; Palano, A.; Eigen, G.; Stugu, B.; Brown, D. N.; Kerth, L. T.; Kolomensky, Yu. G.; Lee, M. J.; Lynch, G.; Koch, H.; Schroeder, T.; Hearty, C.; Mattison, T. S.; McKenna, J. A.; So, R. Y.; Khan, A.; Blinov, V. E.; Buzykaev, A. R.; Druzhinin, V. P.; Golubev, V. B.; Kravchenko, E. A.; Onuchin, A. P.; Serednyakov, S. I.; Skovpen, Yu. I.; Solodov, E. P.; Todyshev, K. Yu.; Lankford, A. J.; Gary, J. W.; Long, O.; Franco Sevilla, M.; Hong, T. M.; Kovalskyi, D.; Richman, J. D.; West, C. A.; Eisner, A. M.; Lockman, W. S.; Panduro Vazquez, W.; Schumm, B. A.; Seiden, A.; Chao, D. S.; Cheng, C. H.; Echenard, B.; Flood, K. T.; Hitlin, D. G.; Kim, J.; Miyashita, T. S.; Ongmongkolkul, P.; Porter, F. C.; Röhrken, M.; Andreassen, R.; Huard, Z.; Meadows, B. T.; Pushpawela, B. G.; Sokoloff, M. D.; Sun, L.; Ford, W. T.; Smith, J. G.; Wagner, S. R.; Ayad, R.; Toki, W. H.; Spaan, B.; Bernard, D.; Verderi, M.; Playfer, S.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Cibinetto, G.; Fioravanti, E.; Garzia, I.; Luppi, E.; Santoro, V.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Martellotti, S.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Zallo, A.; Contri, R.; Monge, M. R.; Passaggio, S.; Patrignani, C.; Bhuyan, B.; Prasad, V.; Adametz, A.; Uwer, U.; Lacker, H. M.; Mallik, U.; Chen, C.; Cochran, J.; Prell, S.; Ahmed, H.; Gritsan, A. V.; Arnaud, N.; Davier, M.; Derkach, D.; Grosdidier, G.; Le Diberder, F.; Lutz, A. M.; Malaescu, B.; Roudeau, P.; Stocchi, A.; Wormser, G.; Lange, D. J.; Wright, D. M.; Coleman, J. P.; Fry, J. R.; Gabathuler, E.; Hutchcroft, D. E.; Payne, D. J.; Touramanis, C.; Bevan, A. J.; di Lodovico, F.; Sacco, R.; Cowan, G.; Brown, D. N.; Davis, C. L.; Denig, A. G.; Fritsch, M.; Gradl, W.; Griessinger, K.; Hafner, A.; Schubert, K. R.; Barlow, R. J.; Lafferty, G. D.; Cenci, R.; Hamilton, B.; Jawahery, A.; Roberts, D. A.; Cowan, R.; Cheaib, R.; Patel, P. M.; Robertson, S. H.; Dey, B.; Neri, N.; Palombo, F.; Cremaldi, L.; Godang, R.; Summers, D. J.; Simard, M.; Taras, P.; de Nardo, G.; Onorato, G.; Sciacca, C.; Raven, G.; Jessop, C. P.; Losecco, J. M.; Honscheid, K.; Kass, R.; Margoni, M.; Morandin, M.; Posocco, M.; Rotondo, M.; Simi, G.; Simonetto, F.; Stroili, R.; Akar, S.; Ben-Haim, E.; Bomben, M.; Bonneaud, G. R.; Briand, H.; Calderini, G.; Chauveau, J.; Leruste, Ph.; Marchiori, G.; Ocariz, J.; Biasini, M.; Manoni, E.; Rossi, A.; Angelini, C.; Batignani, G.; Bettarini, S.; Carpinelli, M.; Casarosa, G.; Chrzaszcz, M.; Forti, F.; Giorgi, M. A.; Lusiani, A.; Oberhof, B.; Paoloni, E.; Rama, M.; Rizzo, G.; Walsh, J. J.; Lopes Pegna, D.; Olsen, J.; Smith, A. J. S.; Anulli, F.; Faccini, R.; Ferrarotto, F.; Ferroni, F.; Gaspero, M.; Pilloni, A.; Piredda, G.; Bünger, C.; Dittrich, S.; Grünberg, O.; Hess, M.; Leddig, T.; Voß, C.; Waldi, R.; Adye, T.; Olaiya, E. O.; Wilson, F. F.; Emery, S.; Vasseur, G.; Aston, D.; Bard, D. J.; Cartaro, C.; Convery, M. R.; Dorfan, J.; Dubois-Felsmann, G. P.; Dunwoodie, W.; Ebert, M.; Field, R. C.; Fulsom, B. G.; Graham, M. T.; Hast, C.; Innes, W. R.; Kim, P.; Leith, D. W. G. S.; Luitz, S.; Luth, V.; Macfarlane, D. B.; Muller, D. R.; Neal, H.; Pulliam, T.; Ratcliff, B. N.; Roodman, A.; Schindler, R. H.; Snyder, A.; Su, D.; Sullivan, M. K.; Va'Vra, J.; Wisniewski, W. J.; Wulsin, H. W.; Purohit, M. V.; Wilson, J. R.; Randle-Conde, A.; Sekula, S. J.; Bellis, M.; Burchat, P. R.; Puccio, E. M. T.; Alam, M. S.; Ernst, J. A.; Gorodeisky, R.; Guttman, N.; Peimer, D. R.; Soffer, A.; Spanier, S. M.; Ritchie, J. L.; Schwitters, R. F.; Izen, J. M.; Lou, X. C.; Bianchi, F.; de Mori, F.; Filippi, A.; Gamba, D.; Lanceri, L.; Vitale, L.; Martinez-Vidal, F.; Oyanguren, A.; Albert, J.; Banerjee, Sw.; Beaulieu, A.; Bernlochner, F. U.; Choi, H. H. F.; King, G. J.; Kowalewski, R.; Lewczuk, M. J.; Lueck, T.; Nugent, I. M.; Roney, J. M.; Sobie, R. J.; Tasneem, N.; Gershon, T. J.; Harrison, P. F.; Latham, T. E.; Band, H. R.; Dasu, S.; Pan, Y.; Prepost, R.; Wu, S. L.; Babar Collaboration

    2016-01-01

    We report on measurements of the decays of B ¯ mesons into the semileptonic final states B ¯ →D(*)π+π-ℓ-ν¯, where D(*) represents a D or D* meson and ℓ- is an electron or a muon. These measurements are based on 471 ×106 B B ¯ pairs recorded with the BABAR detector at the SLAC asymmetric B factory PEP-II. We determine the branching fraction ratios Rπ+π-(*)=B (B ¯ →D(*)π+π-ℓ-ν¯)/B (B ¯ →D(*)ℓ-ν¯) using events in which the second B meson is fully reconstructed. We find Rπ+π-=0.067 ±0.010 ±0.008 and Rπ+π-*=0.019±0.005 ±0.004 , where the first uncertainty is statistical and the second is systematic. Based on these results and assuming isospin invariance, we estimate that B ¯ →D(*)π π ℓ-ν¯ decays, where π denotes either a π± and π0 meson, account for up to half the difference between the measured inclusive semileptonic branching fraction to charm hadrons and the corresponding sum of previously measured exclusive branching fractions.

  12. Ultrabass Sounds of the Giant Star xi Hya

    NASA Astrophysics Data System (ADS)

    2002-05-01

    First Observations of Solar-type Oscillations in a Star Very Different from the Sun Summary About 30 years ago, astronomers realised that the Sun resonates like a giant musical instrument with well-defined periods (frequencies). It forms a sort of large, spherical organ pipe. The energy that excites these sound waves comes from the turbulent region just below the Sun's visible surface. Observations of the solar sound waves (known as " helioseismology ") have resulted in enormous progress in the exploration of the interior of the Sun, otherwise hidden from view. As is the case on Earth, seismic techniques can be applied and the detailed interpretation of the observed oscillation periods has provided quite accurate information about the structure and motions inside the Sun, our central star. It has now also become possible to apply this technique to some solar-type stars. The first observations concerned the northern star eta Bootis (cf. ESO PR 16/94 ). Last year, extensive and much more accurate observations with the 1.2-m Swiss telescope at the ESO La Silla Observatory proved that Alpha Centauri , a solar "twin", behaves very much like the Sun (cf. ESO PR 15/01 ), and that some of the periods are quite similar to those in the Sun. These new observational data were of a superb quality, and that study marked a true break-through in the new research field of " asteroseismology " (seismology of the stars) for solar-type stars. But what about other types of stars, for instance those that are much larger than the Sun? Based on an extremely intensive observing project with the same telescope, an international group of astronomers [1] has found that the giant star xi Hya ("xi" is the small greek letter [2]; "Hya" is an abbreviation of "Hydrae") behaves like a giant sub-ultra-bass instrument . This star is located in the constellation Hydra (the Water-Monster) at a distance of 130 light-years, it has a radius about 10 times that of the Sun and its luminosity is about 60

  13. Giant Impacts on Earth-Like Worlds

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-05-01

    Earth has experienced a large number of impacts, from the cratering events that may have caused mass extinctions to the enormous impact believed to have formed the Moon. A new study examines whether our planets impact history is typical for Earth-like worlds.N-Body ChallengesTimeline placing the authors simulations in context of the history of our solar system (click for a closer look). [Quintana et al. 2016]The final stages of terrestrial planet formation are thought to be dominated by giant impacts of bodies in the protoplanetary disk. During this stage, protoplanets smash into one another and accrete, greatly influencing the growth, composition, and habitability of the final planets.There are two major challenges when simulating this N-body planet formation. The first is fragmentation: since computational time scales as N^2, simulating lots of bodies that split into many more bodies is very computationally intensive. For this reason, fragmentation is usually ignored; simulations instead assume perfect accretion during collisions.Total number of bodies remaining within the authors simulations over time, with fragmentation included (grey) and ignored (red). Both simulations result in the same final number of bodies, but the ones that include fragmentation take more time to reach that final number. [Quintana et al. 2016]The second challengeis that many-body systems are chaotic, which means its necessary to do a large number of simulations to make statistical statements about outcomes.Adding FragmentationA team of scientists led by Elisa Quintana (NASA NPP Senior Fellow at the Ames Research Center) has recently pushed at these challenges by modeling inner-planet formation using a code that does include fragmentation. The team ran 140 simulations with and 140 without the effects of fragmentation using similar initial conditions to understand how including fragmentation affects the outcome.Quintana and collaborators then used the fragmentation-inclusive simulations to

  14. M-giant star candidates identified in LAMOST DR 1

    NASA Astrophysics Data System (ADS)

    Zhong, Jing; Lépine, Sébastien; Li, Jing; Chen, Li; Hou, Jin-Liang; Yang, Ming; Li, Guang-Wei; Zhang, Yong; Hou, Yong-Hui

    2015-08-01

    We perform a discrimination procedure with the spectral index diagram of TiO5 and CaH2+CaH3 to separate M giants from M dwarfs. Using the M giant spectra identified from LAMOST DR1 with high signal-to-noise ratio, we have successfully assembled a set of M giant templates, which show more reliable spectral features. Combining with the M dwarf/subdwarf templates in Zhong et al., we present an extended library of M-type templates which includes not only M dwarfs with a well-defined temperature and metallicity grid but also M giants with subtypes from M0 to M6. Then, the template-fitting algorithm is used to automatically identify and classify M giant stars from LAMOST DR1. The resulting catalog of M giant stars is cross-matched with 2MASS JHKs and WISE W1/W2 infrared photometry. In addition, we calculated the heliocentric radial velocity of all M giant stars by using the cross-correlation method with the template spectrum in a zero-velocity rest frame. Using the relationship between the absolute infrared magnitude MJ and our classified spectroscopic subtype, we derived the spectroscopic distance of M giants with uncertainties of about 40%. A catalog of 8639 M giants is provided. As an additional result of this analysis, we also present a catalog of 101 690 M dwarfs/subdwarfs which are processed by our classification pipeline.

  15. Exotic Earths: forming habitable worlds with giant planet migration.

    PubMed

    Raymond, Sean N; Mandell, Avi M; Sigurdsson, Steinn

    2006-09-01

    Close-in giant planets (e.g., "hot Jupiters") are thought to form far from their host stars and migrate inward, through the terrestrial planet zone, via torques with a massive gaseous disk. Here we simulate terrestrial planet growth during and after giant planet migration. Several-Earth-mass planets also form interior to the migrating jovian planet, analogous to recently discovered "hot Earths." Very-water-rich, Earth-mass planets form from surviving material outside the giant planet's orbit, often in the habitable zone and with low orbital eccentricities. More than a third of the known systems of giant planets may harbor Earth-like planets.

  16. Giant Serpentine Aneurysm of the Middle Cerebral Artery

    PubMed Central

    Lee, Seung Joo; Kwun, Byung Duk; Kim, Chang Jin

    2010-01-01

    Giant serpentine aneurysms are rare and have distinct angiographic findings. The rarity, large size, complex anatomy and hemodynamic characteristics of giant serpentine aneurysms make treatment difficult. We report a case of a giant serpentine aneurysm of the right middle cerebral artery (MCA) that presented as headache. Treatment involved a superficial temporal artery (STA)-MCA bypass followed by aneurysm resection. The patient was discharged without neurological deficits, and early and late follow-up angiography disclosed successful removal of the aneurysm and a patent bypass graft. We conclude that STA-MCA bypass and aneurysm excision is a successful treatment method for a giant serpentine aneurysm. PMID:20856671

  17. Exotic Earths: forming habitable worlds with giant planet migration.

    PubMed

    Raymond, Sean N; Mandell, Avi M; Sigurdsson, Steinn

    2006-09-01

    Close-in giant planets (e.g., "hot Jupiters") are thought to form far from their host stars and migrate inward, through the terrestrial planet zone, via torques with a massive gaseous disk. Here we simulate terrestrial planet growth during and after giant planet migration. Several-Earth-mass planets also form interior to the migrating jovian planet, analogous to recently discovered "hot Earths." Very-water-rich, Earth-mass planets form from surviving material outside the giant planet's orbit, often in the habitable zone and with low orbital eccentricities. More than a third of the known systems of giant planets may harbor Earth-like planets. PMID:16960000

  18. PLUTINO DETECTION BIASES, INCLUDING THE KOZAI RESONANCE

    SciTech Connect

    Lawler, S. M.; Gladman, B.

    2013-07-01

    Because of their relative proximity within the trans-Neptunian region, the plutinos (objects in the 3:2 mean-motion resonance with Neptune) are numerous in flux-limited catalogs, and well-studied theoretically. We perform detailed modeling of the on-sky detection biases for plutinos, with special attention to those that are simultaneously in the Kozai resonance. In addition to the normal 3:2 resonant argument libration, Kozai plutinos also show periodic oscillations in eccentricity and inclination, coupled to the argument of perihelion ({omega}) oscillation. Due to the mean-motion resonance, plutinos avoid coming to pericenter near Neptune's current position in the ecliptic plane. Because Kozai plutinos are restricted to certain values of {omega}, perihelion always occurs out of the ecliptic plane, biasing ecliptic surveys against finding these objects. The observed Kozai plutino fraction f{sub koz}{sup obs} has been measured by several surveys, finding values between 8% and 25%, while the true Kozai plutino fraction f{sub koz}{sup true} has been predicted to be between 10% and 30% by different giant planet migration simulations. We show that f{sub koz}{sup obs} varies widely depending on the ecliptic latitude and longitude of the survey, so debiasing to find the true ratio is complex. Even a survey that covers most or all of the sky will detect an apparent Kozai fraction that is different from f{sub koz}{sup true}. We present a map of the on-sky plutino Kozai fraction that would be detected by all-sky flux-limited surveys. This will be especially important for the Panoramic Survey Telescope and Rapid Response System and Large Synoptic Survey Telescope projects, which may detect large numbers of plutinos as they sweep the sky. f{sub koz}{sup true} and the distribution of the orbital elements of Kozai plutinos may be a diagnostic of giant planet migration; future migration simulations should provide details on their resonant Kozai populations.

  19. Tenosynovial, Diffuse Type Giant Cell Tumor of the Temporomandibular Joint, Diagnosis and Management of a Rare Tumor

    PubMed Central

    Bredell, Marius; Schucknecht, Bernhard; Bode-Lesniewska, Baete

    2015-01-01

    The purpose of this paper was to describe a rare unusual case of primary mandibular condylar tenosynovial giant cell tumor of diffuse type with predominantly intraosseous growth and its management by resection and functional reconstruction with a vascularized costochondral graft. Clinical presentation was swelling in the right condylar area and limited mouth opening with radiological evidence of central bone destruction and magnetic resonance imaging showed central hemosiderin deposition. Fine needle aspiration did not lead to a diagnosis and an open biopsy had to be performed. Management consisted of tumor resection and reconstruction with a free vascularized costochondral graft. Tenosynovial diffuse type giant cell tumor of the temporomandibular joint is very rare. Complete resection leads to a low recurrence rate and reconstruction with a costochondral free vascularized flap leads to an excellent functional outcome. PMID:25699124

  20. Serial neuroimaging of a growing thrombosed giant aneurysm of the distal anterior cerebral artery--case report.

    PubMed

    Kaneko, T; Nomura, M; Yamashima, T; Suzuki, M; Yamashita, J

    2001-01-01

    An 81-year-old female presented with a giant aneurysm of the distal anterior cerebral artery (A3) which grew from a small saccular aneurysm to a huge aneurysm within 36 months before manifesting as a mass lesion. The thrombosed portion of the aneurysm showed growth, whereas the aneurysmal cavity did not change in size. Computed tomography and magnetic resonance imaging showed new bleeding in the thrombosed portion. Hemorrhage into the thrombus and/or aneurysmal wall might have caused the aneurysmal growth. She refused surgery and was discharged with no deficits. Distal anterior cerebral artery aneurysm which shows neuroimaging signs of growth requires regular follow up as such lesions may become giant before manifesting clinical symptoms.

  1. Hollow electron beam with a pulse length 10/sup -4/ s from a multitip explosive-emission cathode

    SciTech Connect

    Vasilevskii, M.A.; Nikonov, A.G.; Roife, I.M.; Savel'ev, Y.M.; Engel'ko, V.I.

    1983-01-01

    In this letter we report experiments in which a hollow electron beam with a pulse length 0/sup -4/ s is produced. The cathode has a conical working surface of 1.5 x 10/sup -3/ cm/sup 2/ on which there are 500 fine tips made of carbon fibers. (AIP)

  2. A nanofiber assembly directed by the non-classical antiparallel β-structure from 4S-(OH) proline polypeptide.

    PubMed

    Bansode, Nitin D; Sonar, Mahesh V; Ganesh, Krishna N

    2016-04-01

    The antiparallel arrangement of two strands of the non-classical β-structure, formed exclusively via cis-4S-(OH) prolyl polypeptide as established by FRET, propagates into self-assembled nanofibers upon conjugation with C12/C14/C16 hydrocarbon chains. PMID:26961970

  3. A nanofiber assembly directed by the non-classical antiparallel β-structure from 4S-(OH) proline polypeptide.

    PubMed

    Bansode, Nitin D; Sonar, Mahesh V; Ganesh, Krishna N

    2016-04-01

    The antiparallel arrangement of two strands of the non-classical β-structure, formed exclusively via cis-4S-(OH) prolyl polypeptide as established by FRET, propagates into self-assembled nanofibers upon conjugation with C12/C14/C16 hydrocarbon chains.

  4. 40 CFR 122.30 - What are the objectives of the storm water regulations for small MS4s?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 22 2014-07-01 2013-07-01 true What are the objectives of the storm... objectives of the storm water regulations for small MS4s? (a) Sections 122.30 through 122.37 are written in a... 402(p)(6) of the Clean Water Act, the purpose of this portion of the storm water program is...

  5. 40 CFR 122.30 - What are the objectives of the storm water regulations for small MS4s?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 23 2012-07-01 2012-07-01 false What are the objectives of the storm... objectives of the storm water regulations for small MS4s? (a) Sections 122.30 through 122.37 are written in a... 402(p)(6) of the Clean Water Act, the purpose of this portion of the storm water program is...

  6. 40 CFR 122.30 - What are the objectives of the storm water regulations for small MS4s?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 21 2010-07-01 2010-07-01 false What are the objectives of the storm... objectives of the storm water regulations for small MS4s? (a) Sections 122.30 through 122.37 are written in a... 402(p)(6) of the Clean Water Act, the purpose of this portion of the storm water program is...

  7. 40 CFR 122.30 - What are the objectives of the storm water regulations for small MS4s?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 23 2013-07-01 2013-07-01 false What are the objectives of the storm... objectives of the storm water regulations for small MS4s? (a) Sections 122.30 through 122.37 are written in a... 402(p)(6) of the Clean Water Act, the purpose of this portion of the storm water program is...

  8. 40 CFR 122.30 - What are the objectives of the storm water regulations for small MS4s?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 22 2011-07-01 2011-07-01 false What are the objectives of the storm... objectives of the storm water regulations for small MS4s? (a) Sections 122.30 through 122.37 are written in a... 402(p)(6) of the Clean Water Act, the purpose of this portion of the storm water program is...

  9. Integral resonator gyroscope

    NASA Technical Reports Server (NTRS)

    Shcheglov, Kirill V. (Inventor); Challoner, A. Dorian (Inventor); Hayworth, Ken J. (Inventor); Wiberg, Dean V. (Inventor); Yee, Karl Y. (Inventor)

    2008-01-01

    The present invention discloses an inertial sensor having an integral resonator. A typical sensor comprises a planar mechanical resonator for sensing motion of the inertial sensor and a case for housing the resonator. The resonator and a wall of the case are defined through an etching process. A typical method of producing the resonator includes etching a baseplate, bonding a wafer to the etched baseplate, through etching the wafer to form a planar mechanical resonator and the wall of the case and bonding an end cap wafer to the wall to complete the case.

  10. The Form and Dimensions of the Giant Synapse of Squids

    NASA Astrophysics Data System (ADS)

    Martin, R.; Miledi, R.

    1986-03-01

    A study was made of the distal giant synapse, and of proximal synapses, in the stellate ganglion of the squid, Loligo vulgaris. For this purpose we injected iontophoretically dyes or cobalt ions into the pre- or postsynaptic axon. The intra-axonal movement of visible dyes was measured. Both presynaptic fibres, the main second order giant axon and the largest accessory axon, branched to make multiple synaptic contacts on the giant motor axons from near the perikarya down to near the exit of the stellar nerves from the ganglion. There were considerable individual variations in the branching patterns of the presynaptic giant axon and in the course and number of the postsynaptic giant axons. More than one accessory axon made contact with the largest motor axon. Fine structural details of the synapse are presented. The size of the contact area made by the main presynaptic axon on the last postsynaptic axon of a medium-sized animal was estimated from low power electron micrographs. We measured and counted synaptic contacts, synaptic vesicles and mitochondria. The fine structure of proximal synapses was found to be very similar to that of the distal synapse. Cobalt- or dye-injected ganglia showed that the perikarya of the axons which fuse to form the postsynaptic giant axons are located in diffuse and overlapping areas of the giant fibre lobe. In freshly hatched larvae the giant synapse was well differentiated; a gradient of differentiation from brain to periphery was detectable. The distal giant synapses of the oegopsid squid Todarodes sagittatus and of Sepia officinalis differed from the Loligo synapse. In Todarodes and Sepia collaterals and processes from both the presynaptic and the postsynaptic giant fibres are shown to meet in numerous contacts in the enlarged sheath surrounding the third order axon. In several respects the Loligo giant fibre system appears to represent in phylogenetical order the more evolved neuronal network.

  11. The Lithium Abundances of a Large Sample of Red Giants

    NASA Astrophysics Data System (ADS)

    Liu, Y. J.; Tan, K. F.; Wang, L.; Zhao, G.; Sato, Bun'ei; Takeda, Y.; Li, H. N.

    2014-04-01

    The lithium abundances for 378 G/K giants are derived with non-local thermodynamic equilibrium correction considered. Among these are 23 stars that host planetary systems. The lithium abundance is investigated, as a function of metallicity, effective temperature, and rotational velocity, as well as the impact of a giant planet on G/K giants. The results show that the lithium abundance is a function of metallicity and effective temperature. The lithium abundance has no correlation with rotational velocity at v sin i < 10 km s-1. Giants with planets present lower lithium abundance and slow rotational velocity (v sin i < 4 km s-1). Our sample includes three Li-rich G/K giants, 36 Li-normal stars, and 339 Li-depleted stars. The fraction of Li-rich stars in this sample agrees with the general rate of less than 1% in the literature, and the stars that show normal amounts of Li are supposed to possess the same abundance at the current interstellar medium. For the Li-depleted giants, Li-deficiency may have already taken place at the main sequence stage for many intermediate mass (1.5-5 M ⊙) G/K giants. Finally, we present the lithium abundance and kinematic parameters for an enlarged sample of 565 giants using a compilation of the literature, and confirm that the lithium abundance is a function of metallicity and effective temperature. With the enlarged sample, we investigate the differences between the lithium abundance in thin-/thick-disk giants, which indicate that the lithium abundance in thick-disk giants is more depleted than that in thin-disk giants.

  12. The lithium abundances of a large sample of red giants

    SciTech Connect

    Liu, Y. J.; Tan, K. F.; Wang, L.; Zhao, G.; Li, H. N.; Sato, Bun'ei; Takeda, Y. E-mail: gzhao@nao.cas.cn

    2014-04-20

    The lithium abundances for 378 G/K giants are derived with non-local thermodynamic equilibrium correction considered. Among these are 23 stars that host planetary systems. The lithium abundance is investigated, as a function of metallicity, effective temperature, and rotational velocity, as well as the impact of a giant planet on G/K giants. The results show that the lithium abundance is a function of metallicity and effective temperature. The lithium abundance has no correlation with rotational velocity at v sin i < 10 km s{sup –1}. Giants with planets present lower lithium abundance and slow rotational velocity (v sin i < 4 km s{sup –1}). Our sample includes three Li-rich G/K giants, 36 Li-normal stars, and 339 Li-depleted stars. The fraction of Li-rich stars in this sample agrees with the general rate of less than 1% in the literature, and the stars that show normal amounts of Li are supposed to possess the same abundance at the current interstellar medium. For the Li-depleted giants, Li-deficiency may have already taken place at the main sequence stage for many intermediate mass (1.5-5 M {sub ☉}) G/K giants. Finally, we present the lithium abundance and kinematic parameters for an enlarged sample of 565 giants using a compilation of the literature, and confirm that the lithium abundance is a function of metallicity and effective temperature. With the enlarged sample, we investigate the differences between the lithium abundance in thin-/thick-disk giants, which indicate that the lithium abundance in thick-disk giants is more depleted than that in thin-disk giants.

  13. Vertical velocities from proper motions of red clump giants

    NASA Astrophysics Data System (ADS)

    López-Corredoira, M.; Abedi, H.; Garzón, F.; Figueras, F.

    2014-12-01

    Aims: We derive the vertical velocities of disk stars in the range of Galactocentric radii of R = 5 - 16 kpc within 2 kpc in height from the Galactic plane. This kinematic information is connected to dynamical aspects in the formation and evolution of the Milky Way, such as the passage of satellites and vertical resonance and determines whether the warp is a long-lived or a transient feature. Methods: We used the PPMXL survey, which contains the USNO-B1 proper motions catalog cross-correlated with the astrometry and near-infrared photometry of the 2MASS point source catalog. To improve the accuracy of the proper motions, the systematic shifts from zero were calculated by using the average proper motions of quasars in this PPMXL survey, and we applied the corresponding correction to the proper motions of the whole survey, which reduces the systematic error. From the color-magnitude diagram K versus (J - K) we selected the standard candles corresponding to red clump giants and used the information of their proper motions to build a map of the vertical motions of our Galaxy. We derived the kinematics of the warp both analytically and through a particle simulation to fit these data. Complementarily, we also carried out the same analysis with red clump giants spectroscopically selected with APOGEE data, and we predict the improvements in accuracy that will be reached with future Gaia data. Results: A simple model of warp with the height of the disk zw(R,φ) = γ(R - R⊙)sin(φ - φw) fits the vertical motions if dot {γ }/γ = -34±17 Gyr-1; the contribution to dot {γ } comes from the southern warp and is negligible in the north. If we assume this 2σ detection to be real, the period of this oscillation is shorter than 0.43 Gyr at 68.3% C.L. and shorter than 4.64 Gyr at 95.4% C.L., which excludes with high confidence the slow variations (periods longer than 5 Gyr) that correspond to long-lived features. Our particle simulation also indicates a probable abrupt decrease

  14. Reactions of synthetic [2Fe-2S] and [4Fe-4S] clusters with nitric oxide and nitrosothiols.

    PubMed

    Harrop, Todd C; Tonzetich, Zachary J; Reisner, Erwin; Lippard, Stephen J

    2008-11-19

    The interaction of nitric oxide (NO) with iron-sulfur cluster proteins results in degradation and breakdown of the cluster to generate dinitrosyl iron complexes (DNICs). In some cases the formation of DNICs from such cluster systems can lead to activation of a regulatory pathway or the loss of enzyme activity. In order to understand the basic chemistry underlying these processes, we have investigated the reactions of NO with synthetic [2Fe-2S] and [4Fe-4S] clusters. Reaction of excess NO(g) with solutions of [Fe2S2(SR)4](2-) (R = Ph, p-tolyl (4-MeC6H4), or 1/2 (CH2)2-o-C6H4) cleanly affords the respective DNIC, [Fe(NO)2(SR)2](-), with concomitant reductive elimination of the bridging sulfide ligands as elemental sulfur. The structure of (Et4N)[Fe(NO)2(S-p-tolyl)2] was verified by X-ray crystallography. Reactions of the [4Fe-4S] clusters, [Fe4S4(SR)4](2-) (R = Ph, CH2Ph, (t)Bu, or 1/2 (CH2)-m-C6H4) proceed in the absence of added thiolate to yield Roussin's black salt, [Fe4S3(NO)7](-). In contrast, (Et4N)2[Fe4S4(SPh)4] reacts with NO(g) in the presence of 4 equiv of (Et4N)(SPh) to yield the expected DNIC. For all reactions, we could reproduce the chemistry effected by NO(g) with the use of trityl-S-nitrosothiol (Ph3CSNO) as the nitric oxide source. These results demonstrate possible pathways for the reaction of iron-sulfur clusters with nitric oxide in biological systems and highlight the importance of thiolate-to-iron ratios in stabilizing DNICs.

  15. MERGING CRITERIA FOR GIANT IMPACTS OF PROTOPLANETS

    SciTech Connect

    Genda, H.; Kokubo, E.; Ida, S.

    2012-01-10

    At the final stage of terrestrial planet formation, known as the giant impact stage, a few tens of Mars-sized protoplanets collide with one another to form terrestrial planets. Almost all previous studies on the orbital and accretional evolution of protoplanets in this stage have been based on the assumption of perfect accretion, where two colliding protoplanets always merge. However, recent impact simulations have shown that collisions among protoplanets are not always merging events, that is, two colliding protoplanets sometimes move apart after the collision (hit-and-run collision). As a first step toward studying the effects of such imperfect accretion of protoplanets on terrestrial planet formation, we investigated the merging criteria for collisions of rocky protoplanets. Using the smoothed particle hydrodynamic method, we performed more than 1000 simulations of giant impacts with various parameter sets, such as the mass ratio of protoplanets, {gamma}, the total mass of two protoplanets, M{sub T}, the impact angle, {theta}, and the impact velocity, v{sub imp}. We investigated the critical impact velocity, v{sub cr}, at the transition between merging and hit-and-run collisions. We found that the normalized critical impact velocity, v{sub cr}/v{sub esc}, depends on {gamma} and {theta}, but does not depend on M{sub T}, where v{sub esc} is the two-body escape velocity. We derived a simple formula for v{sub cr}/v{sub esc} as a function of {gamma} and {theta} (Equation (16)), and applied it to the giant impact events obtained by N-body calculations in the previous studies. We found that 40% of these events should not be merging events.

  16. Dynamics of Giant Planet Polar Vortices

    NASA Astrophysics Data System (ADS)

    Brueshaber, Shawn R.; Sayanagi, Kunio M.

    2016-10-01

    The polar atmospheres of the giant planets have come under increasing interest since a compact, warm-core, stable, cyclonic polar vortex was discovered at each of Saturn's poles. In addition, the south pole of Neptune appears to have a similar feature, and Uranus' north pole is exhibiting activity that could indicate the formation of a polar vortex. We investigate the formation and maintenance of these giant planet polar vortices by varying several key atmospheric dynamics parameters in a forced-dissipative, 1.5-layer shallow water model. Our simulations are run using the EPIC (Explicit Planetary Isentropic Coordinate) global circulation model, to which we have added a gamma-plane rectangular grid option appropriate for simulating polar atmospheric dynamics.In our numerical simulations, we vary the atmospheric deformation radius, planetary rotation rate, storm forcing intensity, and storm vorticity (cyclone-to-anticyclone) ratio to determine what combination of values favors the formation of a polar vortex. We find that forcing the atmosphere by injecting small-scale mass perturbations ("storms") to form either all cyclones, all anticyclones, or equal numbers of both, may all result in a cyclonic polar vortex. Additionally, we examine the role of eddy momentum convergence in the intensification and maintenance of a polar cyclone.Our simulation results are applicable to understanding all four of the solar system giant planets. In the future, we plan to expand our modeling effort with a more realistic 3D primitive equations model, also with a gamma-plane rectangular grid using EPIC. With our 3D primitive equations model, we will study how various vertical atmospheric stratification structures influence the formation and maintenance of a polar cyclone. While our shallow-water model only involves storms of a single layer, a 3D primitive equations model allows us to study how storms of finite vertical extent and at differing levels in the atmosphere may further favor

  17. DO GIANT PLANETS SURVIVE TYPE II MIGRATION?

    SciTech Connect

    Hasegawa, Yasuhiro; Ida, Shigeru E-mail: ida@geo.titech.ac.jp

    2013-09-10

    Planetary migration is one of the most serious problems to systematically understand the observations of exoplanets. We clarify that the theoretically predicted type II, migration (like type I migration) is too fast, by developing detailed analytical arguments in which the timescale of type II migration is compared with the disk lifetime. In the disk-dominated regime, the type II migration timescale is characterized by a local viscous diffusion timescale, while the disk lifetime is characterized by a global diffusion timescale that is much longer than the local one. Even in the planet-dominated regime where the inertia of the planet mass reduces the migration speed, the timescale is still shorter than the disk lifetime except in the final disk evolution stage where the total disk mass decays below the planet mass. This suggests that most giant planets plunge into the central stars within the disk lifetime, and it contradicts the exoplanet observations that gas giants are piled up at r {approx}> 1 AU. We examine additional processes that may arise in protoplanetary disks: dead zones, photoevaporation of gas, and gas flow across a gap formed by a type II migrator. Although they make the type II migration timescale closer to the disk lifetime, we show that none of them can act as an effective barrier for rapid type II migration with the current knowledge of these processes. We point out that gas flow across a gap and the fraction of the flow accreted onto the planets are uncertain and they may have the potential to solve the problem. Much more detailed investigation for each process may be needed to explain the observed distribution of gas giants in extrasolar planetary systems.

  18. Giant Pleomorphic Adenoma of the Parotid Gland.

    PubMed

    Sajid, Muhammad; Rehman, Sajid; Misbah, Junaid

    2015-10-01

    Salivary gland tumours are a relatively rare entity. Pleomorphic adenoma is the most common amongst these, comprising 60 - 70% of all parotid tumours. Pleomorphic adenomas are benign and tend to increase in size slowly. Here we are presenting a case of giant pleomorphic adenoma of the parotid, being the largest in size to be excised in Pakistan in recorded literature measuring 24 x 22 x 12 cm and weighing 1.8 kgs. Superficial parotidectomy was done with an excellent cosmetic outcome. PMID:26522191

  19. GIANT: A Cytoscape Plugin for Modular Networks

    PubMed Central

    Cumbo, Fabio; Paci, Paola; Santoni, Daniele; Di Paola, Luisa; Giuliani, Alessandro

    2014-01-01

    Network analysis provides deep insight into real complex systems. Revealing the link between topological and functional role of network elements can be crucial to understand the mechanisms underlying the system. Here we propose a Cytoscape plugin (GIANT) to perform network clustering and characterize nodes at the light of a modified Guimerà-Amaral cartography. This approach results into a vivid picture of the a topological/functional relationship at both local and global level. The plugin has been already approved and uploaded on the Cytoscape APP store. PMID:25275465

  20. Salym: potential W. Siberian oil giant

    USGS Publications Warehouse

    Clarke, James W.; Rachlin, Jack

    1980-01-01

    SALYM oil field is on the Lempa high of the Salym uplift in the eastern part of the Khanty-Mansiysk depression in the Middle Ob region of West Siberia. The Salym uplift is about 50 km long and 45 km wide and trends north. The Lempa high is 25 km long and 16 km wide; closure is 150 m. The Salym field is about 275 km west of the giant Samotlor field. Stratigraphy. The sedimentary cover overlying the Paleozoic Hercynide basement in the Middle Ob region consists of Jurassic, Lower and Upper Cretaceous, Paleogene, and Quaternary marine and continental sediments.

  1. Ecology. Giant pandas in a changing landscape.

    PubMed

    Loucks, C J; Lü, Z; Dinerstein, E; Wang, H; Olson, D M; Zhu, C; Wang, D

    2001-11-16

    The giant panda has been restricted to several disjunct montane forest populations, and habitat loss and fragmentation are the primary threats to its survival. For pandas to survive, conservation efforts must focus on larger landscapes rather than individual nature reserves. China recently initiated several policies, including the Natural Forest Conservation Program and Grain-to-Green Policy, which provide a historic opportunity to integrate panda conservation into national policies. Simultaneously, China is promoting the Western China Development Program, which calls for substantial infrastructure and hydropower development and economic investments. Integrating panda conservation into these development policies will be a critical challenge.

  2. Giant cystic pheochromocytoma: A silent entity

    PubMed Central

    Gupta, Amit; Bains, Lovenish; Agarwal, Manish Kumar; Gupta, Renu

    2016-01-01

    Pheochromocytoma is a catecholamine secreting tumor that originate from chromaffin cells. Usually, it is solid neoplasm of the adrenal medulla, however cystic pheochromocytoma is a rare neuro-endocrine tumour that is frequently asymptomatic and often diagnosed incidentally on imaging or intra-operatively. Only a few cases of cystic pheochromocytomas have been reported in the world literature. We present a case of giant cystic pheochromocytoma in a 65 years old lady who presented with a large retroperitoneal lump, which is probably the world's third largest pheochromocytoma as per the available indexed literature. PMID:27453669

  3. Giant cystic pheochromocytoma: A silent entity.

    PubMed

    Gupta, Amit; Bains, Lovenish; Agarwal, Manish Kumar; Gupta, Renu

    2016-01-01

    Pheochromocytoma is a catecholamine secreting tumor that originate from chromaffin cells. Usually, it is solid neoplasm of the adrenal medulla, however cystic pheochromocytoma is a rare neuro-endocrine tumour that is frequently asymptomatic and often diagnosed incidentally on imaging or intra-operatively. Only a few cases of cystic pheochromocytomas have been reported in the world literature. We present a case of giant cystic pheochromocytoma in a 65 years old lady who presented with a large retroperitoneal lump, which is probably the world's third largest pheochromocytoma as per the available indexed literature.

  4. Norway threatens shutdown of giant Ekofisk field

    SciTech Connect

    Not Available

    1992-10-19

    This paper reports that The Norwegian Petroleum Directorate has warned Phillips Petroleum Co. Norway AS it will shut down giant Ekofisk oil field over safety concerns before winter 1995-96. Later that day Phillips, operator of the Ekofisk complex in the Norwegian North Sea, the the threat was intended to speed changes in the field's processing and transportation systems. NPD cited studies carried out by Phillips that revealed aging equipment and inadequate maintenance. Seabed subsidence, which led to several of the field's platforms being jacked up 3 m in 1987, made things worse.

  5. Asymptomatic Giant Intraventricular Cysticercosis: A Case Report.

    PubMed

    Teerasukjinda, Ornusa; Wongjittraporn, Suwarat; Tongma, Chawat; Chung, Heath

    2016-07-01

    Neurocysticercosis is a growing health problem in the United States and worldwide. Diagnosis and treatment is challenging especially if the physician is not familiar with this condition. The World Health Organization (WHO) estimates that neurocysticercosis affects 50 million people worldwide, especially in developing countries and causes approximately 50,000 deaths annually.1 Neurocysticercosis is of emerging importance in the United States especially in Hawai'i because of immigration from disease-endemic regions.2 We present a case of a young Chinese immigrant male who presented with impressive imaging studies of a giant intraventricular neurocysticercosis. This case emphasizes the importance of recognizing neurocysticercosis, especially in the immigrant population. PMID:27437162

  6. Asymptomatic Giant Intraventricular Cysticercosis: A Case Report

    PubMed Central

    Wongjittraporn, Suwarat; Tongma, Chawat; Chung, Heath

    2016-01-01

    Neurocysticercosis is a growing health problem in the United States and worldwide. Diagnosis and treatment is challenging especially if the physician is not familiar with this condition. The World Health Organization (WHO) estimates that neurocysticercosis affects 50 million people worldwide, especially in developing countries and causes approximately 50,000 deaths annually.1 Neurocysticercosis is of emerging importance in the United States especially in Hawai‘i because of immigration from disease-endemic regions.2 We present a case of a young Chinese immigrant male who presented with impressive imaging studies of a giant intraventricular neurocysticercosis. This case emphasizes the importance of recognizing neurocysticercosis, especially in the immigrant population. PMID:27437162

  7. The giant aye-aye Daubentonia robusta.

    PubMed

    Simons, E L

    1994-01-01

    Subfossils of a giant form of aye-aye are found at scattered sites in the south and southwest of the island of Madagascar, outside the known distribution of the living, or common, aye-aye. The subfossil aye-aye, named Daubentonia robusta, has massive, robust limb bones implying a species with a body weight 2.5-5 times as great as that of the living species. A mystery exists regarding how a species this large with the same specializations of teeth and manus as the living species could have existed in a xeric environment. PMID:7721200

  8. Giant magnetoresistance in organic spin valves

    SciTech Connect

    Sun, Da-Li; Yin, Lifeng; Sun, Chengjun; Guo, Hangwen; Gai, Zheng; Zhang, Xiaoguang; Ward, Thomas Z; Cheng, Zhaohua; Shen, Jian

    2010-01-01

    Interfacial diffusion between magnetic electrodes and organic spacer layers is a serious problem in the organic spintronics which complicates attempts to understand the spin-dependent transport mechanism and hurts the achievement of a desirably high magnetoresistance (MR). We deposit nanodots instead of atoms onto the organic layer using buffer layer assist growth. Spin valves using this method exhibit a sharper interface and a giant MR of up to {approx}300%. Analysis of the current-voltage characteristics indicates that the spin-dependent carrier injection correlates with the observed MR.

  9. Giant aortic arch aneurysm complicating Kawasaki's disease

    PubMed Central

    Hakim, Kaouthar; Boussada, Rafik; Chaker, Lilia; Ouarda, Fatma

    2014-01-01

    Kawasaki disease (KD) is a common acute vasculitis in pediatric population that usually involves small- and middle-sized arteries, commonly coronary arteries. Although the incidence and natural course of coronary aneurysms after KD are well documented in studies, related reports on peripheral arterial and aortic aneurysms are scarce. We report the occurrence of a giant aortic aneurysm involving the horizontal part of aortic arch in a 28-month-old boy diagnosed with KD. This complication was managed by steroids therapy in the beginning. Because of mechanical complication and potential risk of rupture, surgery was undertaken. PMID:25298695

  10. Giant magnetoresistance in bilayer graphene nanoflakes

    NASA Astrophysics Data System (ADS)

    Farghadan, Rouhollah; Farekiyan, Marzieh

    2016-09-01

    Coherent spin transport through bilayer graphene (BLG) nanoflakes sandwiched between two electrodes made of single-layer zigzag graphene nanoribbon was investigated by means of Landauer-Buttiker formalism. Application of a magnetic field only on BLG structure as a channel produces a perfect spin polarization in a large energy region. Moreover, the conductance could be strongly modulated by magnetization of the zigzag edge of AB-stacked BLG, and the junction, entirely made of carbon, produces a giant magnetoresistance (GMR) up to 100%. Intestinally, GMR and spin polarization could be tuned by varying BLG width and length. Generally, MR in a AB-stacked BLG strongly increases (decreases) with length (width).

  11. Laparoscopic resection of a giant mesenteric cyst.

    PubMed

    Saw, E C; Ramachandra, S

    1994-02-01

    Laparoscopic resection of a giant retroperitoneal, mesenteric cyst in a 38-year-old man who presented with abdominal distension and pedal edema is described. The diagnosis was made by abdominal computed tomography, which revealed a large cystic mass that was causing extrinsic compression of the inferior vena cava and the right ureter. The hospital course was uneventful, and the patient was discharged 2 days postoperatively. This new endoscopic approach offers a useful alternative to the traditional transabdominal excision of a mesenteric cyst and may have some theoretical advantages, including less postoperative pain and shorter convalescence.

  12. Giant Star Clusters Near Galactic Core

    NASA Technical Reports Server (NTRS)

    2001-01-01

    A video sequence of still images goes deep into the Milky Way galaxy to the Arches Cluster. Hubble, penetrating through dust and clouds, peers into the core where two giant clusters shine more brightly than any other clusters in the galaxy. Footage shows the following still images: (1) wide view of Sagittarius constellation; (2) the Palomar Observatory's 2 micron all-sky survey; and (3) an image of the Arches Cluster taken with the Hubble Space Telescope NICMOS instrument. Dr. Don Figer of the Space Telescope Science Institute discusses the significance of the observations and relates his first reaction to the images.

  13. Giant pleomorphic adenoma of the parotid gland.

    PubMed

    Çetin, Mehmet Ali; Ikincioğulları, Aykut; Saygı, Gökçe; Hatipoğlu, Hatice Gül; Köseoğlu, Sabri; Dere, Hüseyin

    2012-01-01

    Pleomorphic adenomas are the most common benign tumors of the salivary glands. These adenomas generally present without pain and are slowly enlarged. However, they can reach enormous sizes, because they are often neglected by the patient and due to late diagnosis and intervention because of fear of surgery or sociocultural factors. This may lead to functional, aesthetic and social problems. In this article, we present a 55-year-old female patient with a giant pleomorphic adenoma in size of 15x15x20 cm, who presented with the complaint of a mass enlarged and swollen for 20 years in her left neck and face and underwent a successful surgery.

  14. Giant ascending colonic diverticulum presenting with intussusception.

    PubMed

    Kim, Ho Jin; Kim, Jin Ha; Moon, Ok In; Kim, Kyung Jong

    2013-10-01

    Diverticular disease of the colon is a common disease, and its incidence is increasing gradually. A giant colonic diverticulum (GCD) is a rare entity and is defined as a diverticulum greater than 4 cm in size. It mainly arises from the sigmoid colon, and possible etiology is a ball-valve mechanism permitting progressive enlargement. A plain abdominal X-ray can be helpful to make a diagnosis initially, and a barium enema and abdominal computed tomography may confirm the diagnosis. Surgical intervention is a definite treatment for a GCD. We report a case of an ascending GCD presenting with intussusception in a young adult.

  15. Giant pericardial cyst mimicking dextrocardia on chest X-ray.

    PubMed

    Hamad, Hamad M; Galrinho, Ana; Abreu, João; Valente, Bruno; Bakero, Luis; Ferreira, Rui C

    2013-01-01

    Pericardial cysts are rare benign congenital malformations, usually small, asymptomatic and detected incidentally on chest X-ray as a mass located in the right costophrenic angle. Giant pericardial cysts are very uncommon and produce symptoms by compressing adjacent structures. In this report, the authors present a case of a symptomatic giant pericardial cyst incorrectly diagnosed as dextrocardia on chest X-ray.

  16. [Prevalence and clinicopathological characteristics of giant cell tumors].

    PubMed

    Estrada-Villaseñor, E G; Linares-González, L M; Delgado-Cedillo, E A; González-Guzmán, R; Rico-Martínez, G

    2015-01-01

    The frequency of giant cell tumors reported in the literature is very variable. Considering that our population has its own features, which distinguish it from the Anglo-Saxon and Asian populations, we think that both the frequency and the clinical characteristics of giant cell tumors in our population are different. The major aim of this paper was to determine the frequency and clinicopathological characteristics of giant cell tumors of the bone. A cross-sectional descriptive study was conducted of the cases diagnosed at our service as giant cell tumors of the bone from January to December 2013. The electronic clinical records, radiologic records and histologic slides from each case were reviewed. Giant cell tumors represented 17% of total bone tumors and 28% of benign tumors. Patients included 13 females and 18 males. The most frequent locations of giant cell tumors were: the proximal tibia, 9 cases (29%), and the distal femur, 6 cases (19%). Forty-five percent of giant cell tumors were associated with aneurysmal bone cyst (ABC) (14 cases) and one case (3%) was malignant. The frequency of giant cell tumors in this case series was intermediate, that is, higher than the one reported in Anglo-Saxon countries (usually low), but without reaching the frequency rates reported in Asian countries (high).

  17. Atypical pulmonary giant hydatid cyst as bilaterally symmetrical solitary cysts.

    PubMed

    Rashid, Saadia; Fatimi, Saulat Hasnain

    2004-09-01

    A pulmonary giant hydatid cyst, a special clinical entity, is rare. Our case involves a young patient who presented with a bilaterally symmetrical solitary cyst in each lung, a feature consistent with congenital lung cysts. The radiological and immunological findings were equivocal. A diagnosis of giant hydatid cyst was made intraoperatively and both cysts were removed conservatively. A follow-up showed complete recovery.

  18. Shoot transcriptome of the Giant Reed, Arundo donax

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The giant reed, Arundo donax, is a perennial grass species that has become an invasive plant in many countries. Expansive stands of A. donax have significant negative impacts on available water resources and efforts are underway to identify biological control agents against this species. The giant r...

  19. [Prevalence and clinicopathological characteristics of giant cell tumors].

    PubMed

    Estrada-Villaseñor, E G; Linares-González, L M; Delgado-Cedillo, E A; González-Guzmán, R; Rico-Martínez, G

    2015-01-01

    The frequency of giant cell tumors reported in the literature is very variable. Considering that our population has its own features, which distinguish it from the Anglo-Saxon and Asian populations, we think that both the frequency and the clinical characteristics of giant cell tumors in our population are different. The major aim of this paper was to determine the frequency and clinicopathological characteristics of giant cell tumors of the bone. A cross-sectional descriptive study was conducted of the cases diagnosed at our service as giant cell tumors of the bone from January to December 2013. The electronic clinical records, radiologic records and histologic slides from each case were reviewed. Giant cell tumors represented 17% of total bone tumors and 28% of benign tumors. Patients included 13 females and 18 males. The most frequent locations of giant cell tumors were: the proximal tibia, 9 cases (29%), and the distal femur, 6 cases (19%). Forty-five percent of giant cell tumors were associated with aneurysmal bone cyst (ABC) (14 cases) and one case (3%) was malignant. The frequency of giant cell tumors in this case series was intermediate, that is, higher than the one reported in Anglo-Saxon countries (usually low), but without reaching the frequency rates reported in Asian countries (high). PMID:27403516

  20. Giant pulmonary hamartoma causing acute right heart failure.

    PubMed

    Joshi, Heman M N; Page, Richard D

    2014-01-01

    Giant pulmonary hamartomas are rare. We describe a case of a 59-year-old female patient with a giant chondroid hamartoma in the lower lobe of the right lung presenting with acute right heart failure. To the best of our knowledge such a unique presentation has not been previously described in the literature. PMID:24384217