WorldWideScience

Sample records for distant electron-electron interactions

  1. Electron-electron interactions in disordered systems

    CERN Document Server

    Efros, AL

    1985-01-01

    ``Electron-Electron Interactions in Disordered Systems'' deals with the interplay of disorder and the Coulomb interaction. Prominent experts give state-of-the-art reviews of the theoretical and experimental work in this field and make it clear that the interplay of the two effects is essential, especially in low-dimensional systems.

  2. Nanoelectromechanical Heat Engine Based on Electron-Electron Interaction

    Science.gov (United States)

    Vikström, A.; Eriksson, A. M.; Kulinich, S. I.; Gorelik, L. Y.

    2016-12-01

    We theoretically show that a nanoelectromechanical system can be mechanically actuated by a heat flow through it via an electron-electron interaction. In contrast to most known actuation mechanisms in similar systems, this new mechanism does not involve an electronic current nor external ac fields. Instead, the mechanism relies on deflection-dependent tunneling rates and a heat flow which is mediated by an electron-electron interaction while an electronic current through the device is prohibited by, for instance, a spin-valve effect. Therefore, the system resembles a nanoelectromechanical heat engine. We derive a criterion for the mechanical instability and estimate the amplitude of the resulting self-sustained oscillations. Estimations show that the suggested phenomenon can be studied using available experimental techniques.

  3. Manifestation of nonlocal electron-electron interaction in graphene

    Science.gov (United States)

    Ulstrup, Søren; Schüler, Malte; Bianchi, Marco; Fromm, Felix; Raidel, Christian; Seyller, Thomas; Wehling, Tim; Hofmann, Philip

    2016-08-01

    Graphene is an ideal platform to study many-body effects due to its semimetallic character and the possibility to dope it over a wide range. Here we study the width of graphene's occupied π band as a function of doping using angle-resolved photoemission. Upon increasing electron doping, we observe the expected shift of the band to higher binding energies. However, this shift is not rigid and the bottom of the band moves less than the Dirac point. We show that the observed shift cannot be accounted for by single-particle effects and local self-energies alone, but that nonlocal many-body effects, in particular exchange interactions, must be taken into account.

  4. Electron-electron interactions in graphene field-induced quantum dots in a high magnetic field

    DEFF Research Database (Denmark)

    Orlof, A.; Shylau, Artsem; Zozoulenko, I. V.

    2015-01-01

    We study the effect of electron-electron interaction in graphene quantum dots defined by an external electrostatic potential and a high magnetic field. To account for the electron-electron interaction, we use the Thomas-Fermi approximation and find that electron screening causes the formation...... of compressible strips in the potential profile and the electron density. We numerically solve the Dirac equations describing the electron dynamics in quantum dots, and we demonstrate that compressible strips lead to the appearance of plateaus in the electron energies as a function of the magnetic field. Finally...

  5. Magneto-Coulomb Drag: Interplay of Electron-Electron Interactions and Landau Quantization

    DEFF Research Database (Denmark)

    Bønsager, Martin Christian; Flensberg, Karsten; Hu, Ben Yu-Kuang

    1996-01-01

    effect. The presence of both electron-electron interactions and Landau quantization results in (i) a twin-peaked structure of rho(21)(B) in the interplateau regions at low temperatures and (ii) for the chemical potential at the center of a Landau level band, a peaked temperature dependence of rho(21)(T...

  6. Electron transport through nano-MOSFET in presence of electron-electron interaction

    Directory of Open Access Journals (Sweden)

    Hamidreza Simchi

    2013-03-01

    Full Text Available We investigate the effect of electron-electron interaction on voltage distribution, charge distribution and current-voltage curve of two dimensional nano-MOSFETs with dimension equal to 1 × 1 nm2, 3 × 3 nm2, and 6 × 6 nm2 by using non-equilibrium Green function method. It is shown that the turn on voltage increases by decreasing the size of sample because of size quantization. Also we show that for a critical drain-source voltage a negative resistance is seen at current-voltage curve of 1 × 1 nm2 sample because of electron-electron interaction, and in consequence it can tolerate lower gate voltage in real practical applications.

  7. Spin Relaxation in GaAs: Importance of Electron-Electron Interactions

    Directory of Open Access Journals (Sweden)

    Gionni Marchetti

    2014-04-01

    Full Text Available We study spin relaxation in n-type bulk GaAs, due to the Dyakonov–Perel mechanism, using ensemble Monte Carlo methods. Our results confirm that spin relaxation time increases with the electronic density in the regime of moderate electronic concentrations and high temperature. We show that the electron-electron scattering in the non-degenerate regime significantly slows down spin relaxation. This result supports predictions by Glazov and Ivchenko. Most importantly, our findings highlight the importance of many-body interactions for spin dynamics: we show that only by properly taking into account electron-electron interactions within the simulations, results for the spin relaxation time—with respect to both electron density and temperature—will reach good quantitative agreement with corresponding experimental data. Our calculations contain no fitting parameters.

  8. Tunable Electron-Electron Interactions in LaAlO_{3}/SrTiO_{3} Nanostructures

    Directory of Open Access Journals (Sweden)

    Guanglei Cheng

    2016-12-01

    Full Text Available The interface between the two complex oxides LaAlO_{3} and SrTiO_{3} has remarkable properties that can be locally reconfigured between conducting and insulating states using a conductive atomic force microscope. Prior investigations of “sketched” quantum dot devices revealed a phase in which electrons form pairs, implying a strongly attractive electron-electron interaction. Here, we show that these devices with strong electron-electron interactions can exhibit a gate-tunable transition from a pair-tunneling regime to a single-electron (Andreev bound state tunneling regime where the interactions become repulsive. The electron-electron interaction sign change is associated with a Lifshitz transition where the d_{xz} and d_{yz} bands start to become occupied. This electronically tunable electron-electron interaction, combined with the nanoscale reconfigurability of this system, provides an interesting starting point towards solid-state quantum simulation.

  9. Tunable Electron-Electron Interactions in LaAlO3/SrTiO3 Nanostructures

    Science.gov (United States)

    Cheng, Guanglei; Tomczyk, Michelle; Tacla, Alexandre B.; Lee, Hyungwoo; Lu, Shicheng; Veazey, Josh P.; Huang, Mengchen; Irvin, Patrick; Ryu, Sangwoo; Eom, Chang-Beom; Daley, Andrew; Pekker, David; Levy, Jeremy

    2016-10-01

    The interface between the two complex oxides LaAlO3 and SrTiO3 has remarkable properties that can be locally reconfigured between conducting and insulating states using a conductive atomic force microscope. Prior investigations of "sketched" quantum dot devices revealed a phase in which electrons form pairs, implying a strongly attractive electron-electron interaction. Here, we show that these devices with strong electron-electron interactions can exhibit a gate-tunable transition from a pair-tunneling regime to a single-electron (Andreev bound state) tunneling regime where the interactions become repulsive. The electron-electron interaction sign change is associated with a Lifshitz transition where the dx z and dy z bands start to become occupied. This electronically tunable electron-electron interaction, combined with the nanoscale reconfigurability of this system, provides an interesting starting point towards solid-state quantum simulation.

  10. Two-photon absorption measurements in graphene fragments: Role of electron-electron interactions

    Science.gov (United States)

    Sandhu, A.; Roberts, A.; Aryanpour, K.; Shukla, A.; Mazumdar, S.

    2012-02-01

    Many-body interactions in graphene are an active field of research. There is a clear evidence of strong electron correlation effects in other carbon based materials which have the same sp^2 hybridization as graphene. For example, in linear-polyenes, the electron-electron interactions are considered responsible for the occurrence of lowest two-photon state below the optical one-photon state. The electronic correlation in these linear systems is a strong function of the chain length. Thus, it is pertinent to question if the two-dimensional graphene fragments also exhibit strong correlation effects and how these effects scale with fragment size. Using a white light super-continuum source, we perform z-scan measurements to extract frequency-dependent two-photon absorption coefficients in symmetric molecular fragments of graphene, e.g. coronene and hexabenzocoronene. A comparison of one-photon and two-photon absorption coefficients is then used to uncover the extent of correlation effects. In the smallest fragment, coronene, our results indicate a strong signature of the Coulomb interactions. We will discuss how the importance of electron-electron interaction varies with system size and its implication for the correlation effects in graphene.

  11. Vibrationally dependent electron-electron interactions in resonant electron transport through single-molecule junctions

    Science.gov (United States)

    Erpenbeck, A.; Härtle, R.; Bockstedte, M.; Thoss, M.

    2016-03-01

    We investigate the role of electronic-vibrational coupling in resonant electron transport through single-molecule junctions, taking into account that the corresponding coupling strengths may depend on the charge and excitation state of the molecular bridge. Within an effective-model Hamiltonian approach for a molecule with multiple electronic states, this requires to extend the commonly used model and include vibrationally dependent electron-electron interaction. We use Born-Markov master equation methods and consider selected models to exemplify the effect of the additional interaction on the transport characteristics of a single-molecule junction. In particular, we show that it has a significant influence on local cooling and heating mechanisms, it may result in negative differential resistance, and it may cause pronounced asymmetries in the conductance map of a single-molecule junction.

  12. Metastable and spin-polarized states in electron systems with localized electron-electron interaction

    Science.gov (United States)

    Sablikov, Vladimir A.; Shchamkhalova, Bagun S.

    2014-05-01

    We study the formation of spontaneous spin polarization in inhomogeneous electron systems with pair interaction localized in a small region that is not separated by a barrier from surrounding gas of non-interacting electrons. Such a system is interesting as a minimal model of a quantum point contact in which the electron-electron interaction is strong in a small constriction coupled to electron reservoirs without barriers. Based on the analysis of the grand potential within the self-consistent field approximation, we find that the formation of the polarized state strongly differs from the Bloch or Stoner transition in homogeneous interacting systems. The main difference is that a metastable state appears in the critical point in addition to the globally stable state, so that when the interaction parameter exceeds a critical value, two states coexist. One state has spin polarization and the other is unpolarized. Another feature is that the spin polarization increases continuously with the interaction parameter and has a square-root singularity in the critical point. We study the critical conditions and the grand potentials of the polarized and unpolarized states for one-dimensional and two-dimensional models in the case of extremely small size of the interaction region.

  13. Van der Waals forces and electron-electron interactions in two strained graphene layers

    Science.gov (United States)

    Sharma, Anand; Harnish, Peter; Sylvester, Alexander; Kotov, Valeri N.

    2014-03-01

    We evaluate the van der Waals (vdW) interaction energy at T=0 between two undoped graphene layers which are separated by a finite distance. Our study is carried out within the Random Phase Approximation and the interaction energy is obtained for variation in the strength of effective Coulomb interaction and anisotropy due to applied uniaxial strain. We consider the following three models for the anisotropic case: a) where one of the two layers is uniaxially strained, b) the two layers are strained in the same direction, and c) one of the layers is strained in the perpendicular direction. We find that for all the three models and any given value of the coupling, the vdW interaction energy increases with increasing anisotropy. The effect is most striking for the case when both the layers are strained in the parallel direction where we observe up to an order of magnitude increase in the strained graphene relative to the unstrained case. We also investigate the effect of intra-layer electron-electron interactions in the region of large separation between the strained graphene layers. We conclude that the many-body contributions to the correlation energy are non-negligible and the vdW interaction energy decreases as a function of increasing distance between the layers. Alexander Sylvester acknowledges financial assistance from the Research Experiences for Undergraduates (REU) Program of the National Science Foundation (NSF) focussing on complex materials.

  14. Pseudogap in the Eliashberg approach based on electron-phonon and electron-electron-phonon interaction

    Energy Technology Data Exchange (ETDEWEB)

    Szczesniak, R. [Institute of Physics, Czestochowa University of Technology (Poland); Institute of Physics, Jan Dlugosz University in Czestochowa (Poland); Durajski, A.P.; Duda, A.M. [Institute of Physics, Czestochowa University of Technology (Poland)

    2017-04-15

    The properties of the superconducting and the anomalous normal state were described by using the Eliashberg method. The pairing mechanism was reproduced with the help of the Hamiltonian, which models the electron-phonon and the electron-electron-phonon interaction (EEPh). The set of the Eliashberg equations, which determines the order parameter function (φ), the wave function renormalization factor (Z), and the energy shift function (χ), was derived. It was proven that for the sufficiently large values of the EEPh potential, the doping dependence of the order parameter (φ/Z) has the analogous course to that observed experimentally in cuprates. The energy gap in the electron density of states is induced by Z and χ - the contribution from φ is negligible. The electron density of states possesses the characteristic asymmetric form and the pseudogap is observed above the critical temperature. (copyright 2017 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  15. Interaction-Free Effects Between Distant Atoms

    CERN Document Server

    Aharonov, Yakir; Elitzur, Avshalom C; Smolin, Lee

    2016-01-01

    A gedankenexperiment is presented where an excited and a ground-state atom are positioned such that, within the former's half-life time, they exchange a photon with 50% probability. A measurement of their energy state will therefore indicate in 50% of the cases that no photon was exchanged. Yet other measurements would reveal that, by the mere possibility of exchange, the two atoms become entangled. Consequently, the "no exchange" result, apparently precluding entanglement, is non-locally established between the atoms by this very entanglement. When densely repeated several times, this result gives rise to the Quantum Zeno effect as well, again exerted between distant atoms without photon exchange. We discuss these experiments as variants of IFM, now generalized for both spatial and temporal uncertainties. We next employ weak measurements for a sharper and simpler elucidation of the paradox. Interpretational issues are discussed in the conclusion, and a resolution is offered within the Two-State Vector Formal...

  16. Transmission zero in a quantum dot with strong electron-electron interaction: Perturbative conductance calculations

    Science.gov (United States)

    Kim, Sejoong; Lee, Hyun-Woo

    2006-05-01

    A pioneering experiment [E. Schuster, E. Buks, M. Heiblum, D. Mahalu, V. Umansky, and Hadas Shtrikman, Nature 385, 417 (1997)] reported the measurement of the transmission phase of an electron traversing a quantum dot and found the intriguing feature of a sudden phase drop in the conductance valleys. Based on the Friedel sum rule for a spinless effective one-dimensional system, it has been previously argued [H.-W. Lee, Phys. Rev. Lett. 82, 2358 (1999)] that the sudden phase drop should be accompanied by the vanishing of the transmission amplitude, or transmission zero. Here we address roles of strong electron-electron interactions on the electron transport through a two-level quantum dot where one level couples with the leads much more strongly than the other level does [P. G. Silvestrov and Y. Imry, Phys. Rev. Lett. 85, 2565 (2000)]. We perform a perturbative conductance calculation with an explicit account of large charging energy and verify that the resulting conductance exhibits transmission zero, in agreement with the analysis based on the Friedel sum rule.

  17. Attractive electron-electron interactions at the LaAlO3/SrTiO3 Interface

    DEFF Research Database (Denmark)

    Prawiroatmodjo, Guenevere E D K

    state is found, and transport characteristics are described to originate from attractive electron-electron interactions that result in a negative effective charging energy U. Further, the excitation spectrum is explored and compared to calculations based on a single-orbital Anderson model with negative...

  18. Crossover of electron-electron interaction effect in Sn-doped indium oxide films

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu-Jie; Gao, Kuang-Hong; Li, Zhi-Qing, E-mail: zhiqingli@tju.edu.cn [Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, Department of Physics, Tianjin University, Tianjin 300072 (China)

    2015-03-09

    We systematically study the structures and electrical transport properties of a series of Sn-doped indium oxide (ITO) films with thickness t ranging from ∼5 to ∼53 nm. Scanning electron microscopy and x-ray diffraction results indicate that the t ≲ 16.8 nm films are polycrystalline, while those t ≳ 26.7 nm films are epitaxially grown along [100] direction. For the epitaxial films, the Altshuler and Aronov electron-electron interaction (EEI) effect governs the temperature behaviors of the sheet conductance σ{sub □} at low temperatures, and the ratios of relative change of Hall coefficient ΔR{sub H}/R{sub H} to relative change of sheet resistance ΔR{sub □}/R{sub □} are ≈2, which is quantitatively consistent with Altshuler and Aronov EEI theory and seldom observed in other systems. For those polycrystalline films, both the sheet conductance and Hall coefficient vary linearly with logarithm of temperature below several tens Kelvin, which can be well described by the current EEI theories in granular metals. We extract the intergranular tunneling conductance of each film by comparing the σ{sub □}(T) data with the predication of EEI theories in granular metals. It is found that when the tunneling conductance is less than the conductance of a single indium tin oxide (ITO) grain, the ITO film reveals granular metal characteristics in transport properties; conversely, the film shows transport properties of homogeneous disordered conductors. Our results indicate that electrical transport measurement can not only reveal the underlying charge transport properties of the film but also be a powerful tool to detect the subtle homogeneity of the film.

  19. Electron-electron interactions and lattice distortions in the perovskite titanates

    Science.gov (United States)

    Bjaalie, Lars

    A two-dimensional electron gas (2DEG) with the unprecedented high density of 3x1014 (corresponding to 1/2 electron per interface unit cell area) can be formed at the interface between SrTiO3 and a rare-earth titanate (RTiO3). The 2DEG resides in the SrTiO3, and arises from a polar discontinuity at the interface. The formation of this 2DEG has led us to study these perovskite titanates in detail. Some of these compounds are Mott insulators, where a Mott-Hubbard gap opens up between partially filled Ti 3 d bands. This talk focuses on the importance of the interplay between electron-electron interactions and lattice distortions in these complex oxides, which we study with density functional theory using a hybrid functional, capable of correctly describing electron localization and Mott-insulating behavior. These effects are crucial to understanding the metal-to-insulator transition as a function of electron density. Indeed, very thin SrTiO3 layers inserted in GdTiO3 show insulating behavior, in contrast to the metallic character of thicker layers in which the electrons form a 2DEG. The same physics is observed in bulk SrTiO3 when doped with 1/2 electron per Ti atom. Charge localization and lattice distortions also govern the formation of small hole polarons in the rare-earth titanates. We demonstrate that these polarons impact the optical absorption measurements commonly used to determine the value of the Mott-Hubbard gap. Work performed in collaboration with Anderson Janotti, Burak Himmetoglu, and Chris G. Van de Walle, and supported by NSF and ARO.

  20. Effect of electron-electron interactions on Rashba-like and spin-split systems

    Science.gov (United States)

    Alexandradinata, A.; Hirsch, J. E.

    2010-11-01

    The role of electron-electron interactions is analyzed for Rashba-like and spin-split systems within a tight-binding single-band Hubbard model with on-site and all nearest-neighbor matrix elements of the Coulomb interaction. By Rashba-like systems we refer to the Dresselhaus and Rashba spin-orbit-coupled phases while spin-split systems have spin-up and spin-down Fermi surfaces shifted relative to each other. Both systems break parity but preserve time-reversal symmetry. They belong to a class of symmetry-breaking ground states that satisfy: (i) electron crystal momentum is a good quantum number, (ii) these states have no net magnetic moment, and (iii) their distribution of “polarized spin” in momentum space breaks the lattice symmetry. For all members of this class, the relevant Coulomb matrix elements are found to be nearest-neighbor exchange J , pair hopping J' , and nearest-neighbor repulsion V . These ground states lower their energy most effectively through J , hence we name them class J states. The competing effects of V-J' on the direct and exchange energies determine the relative stability of class J states. We show that the spin-split and Rashba-like phases are the most favored ground states within class J because they have the minimum anisotropy in polarized spin. We analyze these two states on a square lattice and find that the spin-split phase is always favored for near-empty bands; above a critical filling, we predict a transition from the paramagnetic to the Rashba-like phase at a critical J(Jc1) and a second transition from the Rashba-like to the spin-split state at Jc2>Jc1 . An energetic comparison with ferromagnetism highlights the importance of the role of V in the stability of class J states. We discuss the relevance of our results to (i) the α and β phases proposed by Wu and Zhang in the Fermi-liquid formalism and (ii) experimental observations of spin-orbit splitting in Au(111) surface states.

  1. Pulsed quantum interaction between two distant mechanical oscillators

    Science.gov (United States)

    Vostrosablin, Nikita; Rakhubovsky, Andrey A.; Filip, Radim

    2016-12-01

    Feasible setup for pulsed quantum nondemolition interaction between two distant mechanical oscillators through an optical or microwave mediator is proposed. The proposal uses homodyne measurement of the mediator and feedforward control of the mechanical oscillators to reach the interaction. To verify the quantum nature of the interaction, we investigate the Gaussian entanglement generated in the mechanical modes. We evaluate it under influence of mechanical bath and propagation loss for the mediator and propose ways to optimize the interaction. Finally, both currently available optomechanical and electromechanical platforms are numerically analyzed. The analysis shows that implementation is already feasible with current technology.

  2. Effective mass in bilayer graphene at low carrier densities: The role of potential disorder and electron-electron interaction

    Science.gov (United States)

    Li, J.; Tan, L. Z.; Zou, K.; Stabile, A. A.; Seiwell, D. J.; Watanabe, K.; Taniguchi, T.; Louie, Steven G.; Zhu, J.

    2016-10-01

    In a two-dimensional electron gas, the electron-electron interaction generally becomes stronger at lower carrier densities and renormalizes the Fermi-liquid parameters, such as the effective mass of carriers. We combine experiment and theory to study the effective masses of electrons and holes me* and mh* in bilayer graphene in the low carrier density regime on the order of 1 ×1011c m-2 . Measurements use temperature-dependent low-field Shubnikov-de Haas oscillations observed in high-mobility hexagonal boron nitride supported samples. We find that while me* follows a tight-binding description in the whole density range, mh* starts to drop rapidly below the tight-binding description at a carrier density of n =6 ×1011c m-2 and exhibits a strong suppression of 30% when n reaches 2 ×1011c m-2 . Contributions from the electron-electron interaction alone, evaluated using several different approximations, cannot explain the experimental trend. Instead, the effect of the potential fluctuation and the resulting electron-hole puddles play a crucial role. Calculations including both the electron-electron interaction and disorder effects explain the experimental data qualitatively and quantitatively. This Rapid Communication reveals an unusual disorder effect unique to two-dimensional semimetallic systems.

  3. Effect of electron-electron interaction on the magnetic moment and susceptibility of a parabolic GaAs quantum dot

    Science.gov (United States)

    Boda, Aalu; Kumar, D. Sanjeev; Sankar, I. V.; Chatterjee, Ashok

    2016-11-01

    The problem of a parabolically confined two-dimensional semiconductor GaAs quantum dot with two interacting electrons in the presence of an external magnetic field and the spin-Zeeman interaction is studied using a method of numerical diagonalization. The energy spectrum is calculated as a function of the magnetic field. The magnetic moment (M) and the magnetic susceptibility (χ) show zero temperature diamagnetic peaks due to the exchange induced singlet-triplet transitions. The position and the number of these peaks depend both on the confinement strength of the quantum dot and the strength of the electron-electron interaction (β) .

  4. Parity-violating electric-dipole transitions in helium induced by the electron-electron neutral weak interaction

    Energy Technology Data Exchange (ETDEWEB)

    Esteve, J.G.; Morales, A.; Morales, J.; Nuez-Lagos, R.; Pacheco, A.F.

    1984-04-01

    The parity-violating E1 transitions between the n = 2 levels of atomic helium, induced by the electron-electron neutral weak interaction have been computed by using Coulomb-type wave functions and (up to 84 parameter) Hylleraas wave functions. The parity-violating matrix elements turn out to be of the same order of magnitude as those due to the electron-nucleus weak interaction, thus allowing one to conclude that the relative importance of both effects is to be traced to their corresponding effective coupling constants.

  5. Effect of connecting wires on the decoherence due to electron-electron interaction in a metallic ring

    Science.gov (United States)

    Texier, Christophe

    2007-10-01

    We consider the weak localization in a ring connected to reservoirs through leads of finite length and submitted to a magnetic field. The effect of decoherence due to electron-electron interaction on the harmonics of Al’tshuler-Aronov-Spivak [JETP Lett. 33, 94 (1981)] oscillations is studied, and more specifically the effect of the leads. Two results are obtained for short and long lead regimes. The scale at which the crossover occurs is discussed. The long lead regime is shown to be more realistic experimentally.

  6. Electron-electron interactions in the chemical bond: ``1/3” Effect in the bond length of hydrogen molecule

    Indian Academy of Sciences (India)

    P Ganguly

    2001-10-01

    The prominent ``1/3” effect observed in the Hall effect plateaus of twodimensional electron gas (2DEG) systems has been postulated to indicating 1/3 fractional charge quasiparticle excitations arising from electron-electron interactions. Tunneling shot-noise experiments on 2DEF exhibiting fractional quantum Hall effect (FQHE) shows evidence for tunnelling of particles with and /3 charges for a constant band mass. A ``1/3” effect in the hydrogen molecule is seen in as much as its internuclear distance, - = - + +, with |+/-| = 1/3. This is examined in terms of electron-electron interactions involving electron- and hole quasiparticles, (-) and (ℎ+), equivalent to those observed in FQHE shot-noise experiments. The (/) ratio of the (-) and (ℎ+) quasiparticles is kept at 1: -3. Instead of a 2DEG, these particles are treated as being in flat Bohr orbits. A treatment in the language of charge-flux tube composites for the hydrogen atom as well as the hydrogen molecule is attempted. Such treatment gives important insights into changes in chemical potential and bond energy on crossing a phase boundary during the atom-bond transition as well as on models for FQHE itself.

  7. Evaluation of electron-electron interactions in coupled quantum dots by using far-infrared spectra

    Institute of Scientific and Technical Information of China (English)

    Dong Qing-Rui

    2008-01-01

    We have studied the far-infrared spectra of two-electron vertically coupled quantum dots in an axial magnetic field by exact diagonalization. The calculated results show an obvious difference in role between the interactions for spin S = 1 and for spin S = 0. The results support the possibility to evaluate the interactions by far-infrared spectroscopy in vertically coupled quantum dots.

  8. Electron-electron interactions, topological phase, and optical properties of a charged artificial benzene ring

    Science.gov (United States)

    Ozfidan, Isil; Vladisavljevic, Milos; Korkusinski, Marek; Hawrylak, Pawel

    2015-12-01

    We present a theory of the electronic and optical properties of a charged artificial benzene ring (ABR). The ABR is described by the extended Hubbard model solved using exact diagonalization methods in both real and Fourier space as a function of the tunneling matrix element t , Hubbard on-site repulsion U , and interdot interaction V . In the strongly interacting case, we discuss exact analytical results for the spectrum of the hole in a half-filled ABR dressed by the spin excitations of the remaining electrons. The spectrum is interpreted in terms of the appearance of a topological phase associated with an effective gauge field piercing through the ring. We show that the maximally spin-polarized (S =5 /2 ) and maximally spin-depolarized (S =1 /2 ) states are the lowest energy, orbitally nondegenerate, states. We discuss the evolution of the phase diagram and level crossings as interactions are switched off and the ground state becomes spin nondegenerate but orbitally degenerate S =1 /2 . We present a theory of optical absorption spectra and show that the evolution of the ground and excited states, level crossings, and presence of artificial gauge can be detected optically.

  9. Electron-electron attractive interaction in Maxwell-Chern-Simons QED{sub 3} at zero temperature

    Energy Technology Data Exchange (ETDEWEB)

    Belich, H.; Ferreira Junior, M.M.; Helayel-Neto, J.A. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil). E-mail: belich@cbpf.br; manojr@cbpf.br; helayel@gft.ucp.br; Ferreira Junior, M.M. [Universidade Catolica de Petropolis, RJ (Brazil). Grupo de Fisica Teorica. E-mail: delcima@gft.ucp.br

    2001-04-01

    One discusses the issue of low-energy electron-electron bound states in the Maxwell-Chern-Simons model coupled to QED{sub 3} with spontaneous breaking of a local U(1)-symmetry. The scattering potential, in the non-relativistic limit, steaming from the electron-electron Moeller scattering, mediated by the Maxwell-Chern-Simons-Proca gauge field and the Higgs scalar, might be attractive by fine-tuning properly the physical parameters of the model. (author)

  10. Formation of Hubbard-like bands as a fingerprint of strong electron-electron interactions in FeSe

    Science.gov (United States)

    Watson, Matthew D.; Backes, Steffen; Haghighirad, Amir A.; Hoesch, Moritz; Kim, Timur K.; Coldea, Amalia I.; Valentí, Roser

    2017-02-01

    We use angle-resolved photoemission spectroscopy (ARPES) to explore the electronic structure of single crystals of FeSe over a wide range of binding energies and study the effects of strong electron-electron correlations. We provide evidence for the existence of "Hubbard-like bands" at high binding energies consisting of incoherent many-body excitations originating from Fe 3 d states in addition to the renormalized quasiparticle bands near the Fermi level. Many high-energy features of the observed ARPES data can be accounted for when incorporating the effects of strong local Coulomb interactions in calculations of the spectral function via dynamical mean-field theory, including the formation of a Hubbard-like band. This shows that over the energy scale of several eV, local correlations arising from the on-site Coulomb repulsion and Hund's coupling are essential for a proper understanding of the electronic structure of FeSe and other related iron-based superconductors.

  11. Non-Chemical Distant Cellular Interactions as a potential confounder of cell biology experiments.

    Science.gov (United States)

    Farhadi, Ashkan

    2014-01-01

    Distant cells can communicate with each other through a variety of methods. Two such methods involve electrical and/or chemical mechanisms. Non-chemical, distant cellular interactions may be another method of communication that cells can use to modify the behavior of other cells that are mechanically separated. Moreover, non-chemical, distant cellular interactions may explain some cases of confounding effects in Cell Biology experiments. In this article, we review non-chemical, distant cellular interactions studies to try to shed light on the mechanisms in this highly unconventional field of cell biology. Despite the existence of several theories that try to explain the mechanism of non-chemical, distant cellular interactions, this phenomenon is still speculative. Among candidate mechanisms, electromagnetic waves appear to have the most experimental support. In this brief article, we try to answer a few key questions that may further clarify this mechanism.

  12. Non-Chemical Distant Cellular Interactions as a potential confounder of Cell Biology Experiments

    Directory of Open Access Journals (Sweden)

    Ashkan eFarhadi

    2014-10-01

    Full Text Available Distant cells can communicate with each other through a variety of methods. Two such methods involve electrical and/or chemical mechanisms. Non-chemical, distant cellular interactions may be another method of communication that cells can use to modify the behavior of other cells that are mechanically separated. Moreover, non-chemical, distant cellular interactions may explain some cases of confounding effects in Cell Biology experiments. In this article, we review non-chemical, distant cellular interactions studies to try to shed light on the mechanisms in this highly unconventional field of cell biology. Despite the existence of several theories that try to explain the mechanism of non-chemical, distant cellular interactions, this phenomenon is still speculative. Among candidate mechanisms, electromagnetic waves appear to have the most experimental support. In this brief article, we try to answer a few key questions that may further clarify this mechanism.

  13. Photoinduction of cyclosis-mediated interactions between distant chloroplasts.

    Science.gov (United States)

    Bulychev, Alexander A; Komarova, Anna V

    2015-01-01

    Communications between chloroplasts and other organelles based on the exchange of metabolites, including redox active substances, are recognized as a part of intracellular regulation, chlororespiration, and defense against oxidative stress. Similar communications may operate between spatially distant chloroplasts in large cells where photosynthetic and respiratory activities are distributed unevenly under fluctuating patterned illumination. Microfluorometry of chlorophyll fluorescence in vivo in internodal cells of the alga Chara corallina revealed that a 30-s pulse of localized light induces a transient increase (~25%) in F' fluorescence of remote cell parts exposed to dim background light at a 1.5-mm distance on the downstream side from the illuminated spot in the plane of unilateral cytoplasmic streaming but has no effect on F' at equal distance on the upstream side. An abrupt arrest of cytoplasmic streaming for about 30s by triggering the action potential extended either the ascending or descending fronts of the F' fluorescence response, depending on the exact moment of streaming cessation. The response of F' fluorescence to localized illumination of a distant cell region was absent in dark-adapted internodes, when the localized light was applied within the first minute after switching on continuous background illumination of the whole cell, but it appeared in full after longer exposures to continuous background light. These results and the elimination of the F' response by methyl viologen known to redirect electron transport pathways beyond photosystem I indicate the importance of photosynthetic induction and the stromal redox state for long-distance communications of chloroplasts in vivo.

  14. Universal increase in the superconducting critical temperature of two-dimensional semiconductors at low doping by the electron-electron interaction.

    Science.gov (United States)

    Calandra, Matteo; Zoccante, Paolo; Mauri, Francesco

    2015-02-20

    In two-dimensional multivalley semiconductors, at low doping, even a moderate electron-electron interaction enhances the response to any perturbation inducing a valley polarization. If the valley polarization is due to the electron-phonon coupling, the electron-electron interaction results in an enhancement of the superconducting critical temperature. By performing first-principles calculations beyond density functional theory, we prove that this effect accounts for the unconventional doping dependence of the superconducting transition temperature (T(c)) and of the magnetic susceptibility measured in Li(x)ZrNCI. Finally, we discuss what are the conditions for a maximal T(c) enhancement in weakly doped two-dimensional semiconductors.

  15. Photon-mediated interactions between distant artificial atoms.

    Science.gov (United States)

    van Loo, Arjan F; Fedorov, Arkady; Lalumière, Kevin; Sanders, Barry C; Blais, Alexandre; Wallraff, Andreas

    2013-12-20

    Photon-mediated interactions between atoms are of fundamental importance in quantum optics, quantum simulations, and quantum information processing. The exchange of real and virtual photons between atoms gives rise to nontrivial interactions, the strength of which decreases rapidly with distance in three dimensions. Here, we use two superconducting qubits in an open one-dimensional transmission line to study much stronger photon-mediated interactions. Making use of the possibility to tune these qubits by more than a quarter of their transition frequency, we observe both coherent exchange interactions at an effective separation of 3λ/4 and the creation of super- and subradiant states at a separation of one photon wavelength λ. In this system, collective atom-photon interactions and applications in quantum communication may be explored.

  16. Electrolyte-gated charge transport in molecularly linked gold nanoparticle films: The transition from a Mott insulator to an exotic metal with strong electron-electron interactions

    Science.gov (United States)

    Tie, M.; Dhirani, A.-A.

    2016-09-01

    Strong electron-electron interactions experienced by electrons as they delocalize are widely believed to play a key role in a range of remarkable phenomena such as high Tc superconductivity, colossal magnetoresistance, and others. Strongly correlated electrons are often described by the Hubbard model, which is the simplest description of a correlated system and captures important gross features of phase diagrams of strongly correlated materials. However, open challenges in this field include experimentally mapping correlated electron phenomena beyond those captured by the Hubbard model, and extending the model accordingly. Here we use electrolyte gating to study a metal-insulator transition (MIT) in a new class of strongly correlated material, namely, nanostructured materials, using 1,4-butanedithiol-linked Au nanoparticle films (NPFs) as an example. Electrolyte gating provides a means for tuning the chemical potential of the materials over a wide range, without significantly modifying film morphology. On the insulating side of the transition, we observe Efros-Shklovskii variable range hopping and a soft Coulomb gap, evidencing the importance of Coulomb barriers. On the metallic side of the transition, we observe signatures of strong disorder mediated electron-electron correlations. Gating films near MIT also reveal a zero-bias conductance peak, which we attribute to a resonance at the Fermi level predicted by the Hubbard and Anderson impurity models when electrons delocalize and experience strong Coulomb electron-electron interactions. This study shows that by enabling large changes in carrier density, electrolyte gating of Au NPFs is a powerful means for tuning through the Hubbard MIT in NPFs. By revealing the range of behaviours that strongly correlated electrons can exhibit, this platform can guide the development of an improved understanding of correlated materials.

  17. Magnetization and susceptibility of a parabolic InAs quantum dot with electron-electron and spin-orbit interactions in the presence of a magnetic field at finite temperature

    Science.gov (United States)

    Kumar, D. Sanjeev; Mukhopadhyay, Soma; Chatterjee, Ashok

    2016-11-01

    The magnetization and susceptibility of a two-electron parabolic quantum dot are studied in the presence of electron-electron and spin-orbit interactions as a function of magnetic field and temperature. The spin-orbit interactions are treated by a unitary transformation and an exactly soluble parabolic interaction model is considered to mimic the electron-electron interaction. The theory is finally applied to an InAs quantum dot. Magnetization and susceptibility are calculated using canonical ensemble approach. Our results show that Temperature has no effect on magnetization and susceptibility in the diamagnetic regime whereas electron-electron interaction reduces them. The temperature however reduces the height of the paramagnetic peak. The Rashba spin-orbit interaction is shown to shift the paramagnetic peak towards higher magnetic fields whereas the Dresselhaus spin-orbit interaction shifts it to the lower magnetic field side. Spin-orbit interaction has no effect on magnetization and susceptibility at larger temperatures.

  18. Modified Monte Carlo method for study of electron transport in degenerate electron gas in the presence of electron-electron interactions, application to graphene

    Science.gov (United States)

    Borowik, Piotr; Thobel, Jean-Luc; Adamowicz, Leszek

    2017-07-01

    Standard computational methods used to take account of the Pauli Exclusion Principle into Monte Carlo (MC) simulations of electron transport in semiconductors may give unphysical results in low field regime, where obtained electron distribution function takes values exceeding unity. Modified algorithms were already proposed and allow to correctly account for electron scattering on phonons or impurities. Present paper extends this approach and proposes improved simulation scheme allowing including Pauli exclusion principle for electron-electron (e-e) scattering into MC simulations. Simulations with significantly reduced computational cost recreate correct values of the electron distribution function. Proposed algorithm is applied to study transport properties of degenerate electrons in graphene with e-e interactions. This required adapting the treatment of e-e scattering in the case of linear band dispersion relation. Hence, this part of the simulation algorithm is described in details.

  19. Universal power-law decay of electron-electron interactions due to nonlinear screening in a Josephson junction array

    Science.gov (United States)

    Otten, Daniel; Rubbert, Sebastian; Ulrich, Jascha; Hassler, Fabian

    2016-09-01

    Josephson junctions are the most prominent nondissipative and at the same time nonlinear elements in superconducting circuits allowing Cooper pairs to tunnel coherently between two superconductors separated by a tunneling barrier. Due to this, physical systems involving Josephson junctions show highly complex behavior and interesting novel phenomena. Here, we consider an infinite one-dimensional chain of superconducting islands where neighboring islands are coupled by capacitances. We study the effect of Josephson junctions shunting each island to a common ground superconductor. We treat the system in the regime where the Josephson energy exceeds the capacitive coupling between the islands. For the case of two offset charges on two distinct islands, we calculate the interaction energy of these charges mediated by quantum phase slips due to the Josephson nonlinearities. We treat the phase slips in an instanton approximation and map the problem onto a classical partition function of interacting particles. Using the Mayer cluster expansion, we find that the interaction potential of the offset charges decays with a universal inverse-square power-law behavior.

  20. Electron-Electron and Electron-Phonon interactions effects on the tunnel electronic spectrum of PbS quantum dots

    Science.gov (United States)

    Wang, Hongyue; Lhuillier, Emmanuel; Yu, Qian; Mottaghizadeh, Alireza; Ulysse, Christian; Zimmers, Alexandre; Dubertret, Benoit; Aubin, Herve

    2015-03-01

    We present a tunnel spectroscopy study of the electronic spectrum of single PbS Quantum Dots (QDs) trapped between nanometer-spaced electrodes, measured at low temperature T=5 K. The carrier filling of the QD can be controlled either by the drain voltage in the shell filling regime or by a gate voltage. In the empty QD, the tunnel spectrum presents the expected signature of the 8x degenerated excited levels. In the drain controlled shell filling regime, the levels degeneracies are lifted by the global electrostatic Coulomb energy of the QD; in the gate controlled shell filling regime, the levels degeneracies are lifted by the intra-Coulomb interactions. In the charged quantum dot, electron-phonons interactions lead to the apparition of Franck-Condon side bands on the single excited levels and possibly Franck Condon blockade at low energy. The sharpening of excited levels at higher gate voltage suggests that the magnitude of electron-phonon interactions is decreased upon increasing the electron filling in the quantum dot. This work was supported by the French ANR Grants 10-BLAN-0409-01, 09-BLAN-0388-01, by the Region Ile-de-France in the framework of DIM Nano-K and by China Scholarship Council.

  1. Influence of variations in the electron-electron interaction on the ground state metric space "band structure" of a two-electron magnetic system

    Science.gov (United States)

    Sharp, P. M.; D'Amico, I.

    2016-02-01

    We consider a model system of two electrons confined in a two-dimensional harmonic oscillator potential, with the electrons interacting via an α / r2 potential, and subject to a magnetic field applied perpendicular to the plane of confinement. Our results show that variations in the strength of the electron-electron interaction generate a "band structure" in ground state metric spaces, which shares many characteristics with those generated as a result of varying the confinement potential. In particular, the metric spaces for wavefunctions, particle densities, and paramagnetic current densities all exhibit distinct "bands" and "gaps". The behavior of the polar angle of the bands also shares traits with that obtained by varying the confinement potential, but the behavior of the arc lengths of the bands on the metric space spheres can be seen to be different for the two cases and opposite for a large range of angular momentum values. The findings here and in Refs. [1,2] demonstrate that the "band structure" that arises in ground state metric spaces when a magnetic field is applied is a robust feature.

  2. Effects of the electron-electron interaction on electronic transport through the antibonding orbital of a longitudinally embedded double quantum dot

    Science.gov (United States)

    Aguiar-Hualde, J. M.; Chiappe, G.; Louis, E.

    2007-08-01

    The effects of the on-site electron-electron (e-e) interaction U on the electronic transport across two longitudinally embedded quantum dots in the regime in which the antibonding (AB) state of the isolated composite system is aligned with the Fermi level at the leads are investigated. This regime occurs when the dot orbital energy γd is negative and equal in magnitude to the hopping probability between the orbitals on the two dots. In the noninteracting case, the conductance approaches asymptotically the conductance quantum G0=2e2/h as γd decreases; in addition, the contribution of the AB channel to the conductance tends to 1. As shown here, this picture is substantially modified by the e-e interaction. For finite U , the conductance versus γd shows a maximum at which the value G0 is reached, being supported in this case by the two channels (bonding and antibonding); the relative weight of each channel depends on the actual value of the e-e interaction. In the limit γd=-∞ , the conductance is supported only by the AB channel (as in the noninteracting case), but it is always smaller than G0 . While the mechanism underlying these results is mainly one body for small U , the Kondo effect and quantum interference come into play at large U . The effects of the e-e interaction increase significantly as the leads-dots coupling decreases, in particular, the range over which the conductance is non-negligible is significantly narrowed. The possible implications on a physically related system, a hydrogen molecule longitudinally bridging two Pt electrodes, are discussed.

  3. DIMEL - A New Interactive System for Distant E-Learning Management

    Directory of Open Access Journals (Sweden)

    C. Katansky

    2012-04-01

    Full Text Available The article presents the basic results of a study, dealing with the problems of e-learning and e-teaching development in the University of Sofia. A new system - DIMEL (Distant and Interactive Management of E-Learning was implemented by the „Management of Education” training courses with adult students. The courses are part of the continuing vocational training (the qualifications upgrading of school principals, vice principals and other managing staff in the sector of education. The system DIMEL uses an original interactive training management technology, covering the field of e-learning and e-teaching activities, via digital library logistic platform. The author performs this project research in collaboration with the University Library „St. Kliment Ohridski”.

  4. Virtual Replica of Matter in Bivacuum & Possible Mechanism of Distant Mind - Matter and Mind - Mind Interaction

    CERN Document Server

    Kaivarainen, A

    2001-01-01

    The original mechanism of bivacuum mediated Mind-Matter and Mind-Mind interaction, proposed here, is based on the following stages of long term efforts: New dynamic models of bivacuum, sub-elementary particles and corpuscle-wave [C-W] duality, as a background of Superunification; New Hierarchic theory of liquids and solids; New Hierarchic model of elementary act of consciousness; Virtual Replica (VR)of matter, including living organisms, in bivacuum; The distant resonant [Mind-Bivacuum-Matter] and [Mind-Bivacuum-Mind] interaction, mediated by Bivacuum oscillation (BvO, accompanied by virtual particles/antiparticles pressure oscillation. The latter factor is related to oscillation of vacuum permittivity and permeability. The virtual replica (VR) of condensed matter (living organisms in private case), may influence the properties of virtual pressure of bivacuum in following manner: 1) changing the amplitude of virtual pressure waves (VPW) in-phase with Bivacuum oscillations (BvO). This factor is dependent on fr...

  5. One-electron versus electron-electron interaction contributions to the spin-spin coupling mechanism in nuclear magnetic resonance spectroscopy: analysis of basic electronic effects.

    Science.gov (United States)

    Gräfenstein, Jürgen; Cremer, Dieter

    2004-12-22

    For the first time, the nuclear magnetic resonance (NMR) spin-spin coupling mechanism is decomposed into one-electron and electron-electron interaction contributions to demonstrate that spin-information transport between different orbitals is not exclusively an electron-exchange phenomenon. This is done using coupled perturbed density-functional theory in conjunction with the recently developed J-OC-PSP [=J-OC-OC-PSP: Decomposition of J into orbital contributions using orbital currents and partial spin polarization)] method. One-orbital contributions comprise Ramsey response and self-exchange effects and the two-orbital contributions describe first-order delocalization and steric exchange. The two-orbital effects can be characterized as external orbital, echo, and spin transport contributions. A relationship of these electronic effects to zeroth-order orbital theory is demonstrated and their sign and magnitude predicted using simple models and graphical representations of first order orbitals. In the case of methane the two NMR spin-spin coupling constants result from totally different Fermi contact coupling mechanisms. (1)J(C,H) is the result of the Ramsey response and the self-exchange of the bond orbital diminished by external first-order delocalization external one-orbital effects whereas (2)J(H,H) spin-spin coupling is almost exclusively mitigated by a two-orbital steric exchange effect. From this analysis, a series of prediction can be made how geometrical deformations, electron lone pairs, and substituent effects lead to a change in the values of (1)J(C,H) and (2)J(H,H), respectively, for hydrocarbons.

  6. Distant exchange interactions in Cd1-xMnxS from magnetization steps method

    Science.gov (United States)

    Gratens, X.; Chitta, V.

    2017-07-01

    Three new distant neighbor (DN) antiferromagnetic exchange constants have been measured in wurtzite Cd1-xMnxS (x = 0.0087 and x = 0.0278) using the magnetization steps method in the millikelvin regime. The second (J(2)), third (J(3)), and fourth (J(4)) largest exchange constants (after the two first neighbor exchange interactions J1 and J1' ) have been measured. The results are J(2) = 300 ± 10 mK, J(3) = 173 ± 10 mK, and J(4) = 55 ± 10 mK. No significant change of the exchange constant values has been observed as a function of the Mn concentration. The mapping of the DN exchange interactions has been investigated within a sphere of radius 2 times the nearest neighbors distance. The only way to identify the J constants was using the number coordination Zn of the different DN classes: J(2) is associated to DN classes with Zn = 6, J(3) with Zn = 12, and J(4) is ascribed to a group of three DN classes with J values around J(4). The magnitude of the J constants is not in agreement with theoretical predictions of the monotonic decrease of the exchange constant with increasing distance. The present results are similar to those obtained for Cd1-xMnxSe but are different from the ones obtained for Zn1-xMnxO. The present work confirms the long-range character of the DN exchange interactions in the wurtzite type Mn-based II-VI diluted magnetic semiconductors.

  7. Interactive tele-education applied to a distant clinical microbiology specialization university course.

    Science.gov (United States)

    Andreazzi, Denise B; Rossi, Flávia; Wen, Chao L

    2011-09-01

    The microbiology laboratory provides a strategic support for infectious disease diagnosis and also alerts the medical community about bacterial resistance to antibiotics. The microbiologists' training is a challenge in Brazil, a country with an extensive territory, a diverse population, and disparity of resource allocation. The aim of this study was to implement an interactive tele-educational course in clinical microbiology to reach distant laboratory workers and to improve their professional skills. The course scientific content was defined according to competences associated, distributed in 560 h, with laboratory practices (knowledge matrix-contextual education). The 11-module course structure comprised 70% distance learning, 22% on campus (integrated modules), and 8% monographs. The group included 7 physicians and 21 microbiologists from 20 different Brazilian cities. The time flexibility and location were the two main reasons for student participation, thus decreasing absences to the workplace, different from the traditional teaching methodologies. The group performance was measured by monthly evaluations, and 1 year postcourse, the researcher visited their workplace. There was significant improvement in microbiological practices performed before compared with after group participation. Therefore, 76.9% of laboratory practices were modified because of the knowledge acquired in the course. Students showed behavioral changes in relation to performance in infection control as well as on the dissemination of their knowledge. This specialization course using distance education did not compromise the quality. This educational methodology represents an alternative to teach clinical microbiology to laboratory workers from remote hospitals, as a nationwide continuing educational strategy.

  8. Electron--electron double resonance study of magnetic energy transfer between trapped electrons and radicals in organic glasses: Relation between dipolar cross relaxation times and dipolar interaction distances

    Energy Technology Data Exchange (ETDEWEB)

    Lin, D.P.; Feng, D.F.; Ngo, F.Q.H.; Kevan, L.

    1976-11-15

    Electron--electron double resonance (ELDOR) has been used to measure cross-relaxation times between trapped electrons and trapped radicals produced by ..gamma.. irradiation of 2-methyltetrahydrofuran and 3-methylhexane organic glasses. The cross-relaxation times are measured as a function of temperature, radiation dose, and the frequency difference ..delta..f of the microwave frequencies used. The cross-relaxation times are nearly temperature independent and depend on ..delta..f/sup 2/ at doses where the spin concentrations approach uniformity; these features indicate the dominance of single step over multistep cross-relaxation processes. Equations have been derived to relate the dipolar cross-relaxation distance to the measured cross-relaxation times, and it is suggested that the cross-relaxation line shape is Lorentzian in magnetically dilute systems. Typical electron--radical correlation distances in these organic glasses are 10 A. (AIP)

  9. Electron-electron interaction in strong electromagnetic fields: the two-electron contribution to the ground-state energy in He-like uranium.

    Science.gov (United States)

    Gumberidze, A; Stöhlker, Th; Banaś, D; Beckert, K; Beller, P; Beyer, H F; Bosch, F; Cai, X; Hagmann, S; Kozhuharov, C; Liesen, D; Nolden, F; Ma, X; Mokler, P H; Orsić-Muthig, A; Steck, M; Sierpowski, D; Tashenov, S; Warczak, A; Zou, Y

    2004-05-21

    Radiative recombination transitions into the ground state of cooled bare and hydrogenlike uranium ions were measured at the storage ring ESR. By comparing the corresponding x-ray centroid energies, this technique allows for a direct measurement of the electron-electron contribution to the ionization potential in the heaviest He-like ions. For the two-electron contribution to the ionization potential of He-like uranium we obtain a value of 2248+/-9 eV. This represents the most accurate determination of two-electron effects in the domain of high-Z He-like ions, and the accuracy reaches already the size of the specific two-electron radiative QED corrections.

  10. Electrical resistivity of the hole doped La{sub 0.8}Sr{sub 0.2}MnO{sub 3} manganites: Role of electron-electron/phonon/magnon interactions

    Energy Technology Data Exchange (ETDEWEB)

    Varshney, Dinesh, E-mail: vdinesh33@rediffmail.com [School of Physics, Vigyan Bhavan, Devi Ahilya University, Khandwa Road Campus, Indore 452001 (India); Dodiya, N. [School of Physics, Vigyan Bhavan, Devi Ahilya University, Khandwa Road Campus, Indore 452001 (India)

    2011-10-03

    Highlights: {yields} La{sub 1-x}K{sub x}MnO{sub 3} manganites crystallize in rhombohedral structure (R3-bar C). {yields} K doping at La site enhances metal-insulator transition. {yields} Metallic resistivity shows electron, magnon and phonon scattering are significant. {yields} Polaronic effects are the major proponents for semiconducting resistivity. {yields} Resistivity upturn contributes to Coulomb and Kondo-like scattering. - Abstract: In this work, a quantitative analysis of reported metallic and insulating behaviour of resistivity in perovskite manganites La{sub 0.8}Sr{sub 0.2}MnO{sub 3} is established. An effective inter-ionic interaction potential (EIoIP) with the long-range Coulomb, van der Waals (vdW) interaction and short-range repulsive interaction up to second-neighbour ions within the Hafemeister and Flygare approach was employed to estimate the Debye and Einstein temperature and was found to be consistent with the available experimental data. The electrical resistivity data in low temperature regime (T < T{sub MI}) were theoretically analyzed within the framework of the classical electron-phonon model of resistivity, for example, the Bloch-Gruneisen (BG) model. The Bloch-Gruneisen (BG) model and terms T{sup 2}, T{sup 4.5} simplify the electron-phonon, electron-electron and electron-magnon scattering processes. On the other hand, in high temperature regime (T > T{sub MI}) the insulating nature is discussed with Mott's variable range hopping (VRH) model and small polaron conduction (SPC) model. For T > T{sub MI} SPC model is more appropriate than the VRH model. The SPC model consistently retraces the higher temperature resistivity behaviour (T > {theta}{sub D}/2). The metallic and semiconducting resistivity behaviours of La{sub 0.8}Sr{sub 0.2}MnO{sub 3} manganites are analyzed, to the knowledge, for the first time highlighting the importance of electron-phonon, electron-electron, electron-magnon interactions and small polaron conduction.

  11. The importance of the on-site electron-electron interaction for the magnetic coupling in the zigzag spin-chain compound In2VO5

    KAUST Repository

    Wang, Hao

    2010-09-27

    We present first-principles electronic structure calculations for the zigzag spin-chain compound In2VO5 using the generalized gradient approximation both with and without inclusion of an on-site Coulomb interaction. It has been proposed that In2VO5 is characterized by itinerant V 3d electrons at high temperature and localized electrons at low temperature. Consequently, it is to be expected that electronic correlations play an important role for the magnetic transition from ferromagnetic to antiferromagnetic exchange around 120 K. In this context, we study the electronic and magnetic properties of a set of possible spin configurations. Our calculations show that inclusion of an on-site Coulomb interaction in fact changes the ground state from ferromagnetic to antiferromagnetic. © 2010 IOP Publishing Ltd.

  12. Time structure of gamma-ray signals generated in line-of-sight interactions of cosmic rays from distant blazars

    CERN Document Server

    Prosekin, Anton; Kusenko, Alexander; Aharonian, Felix

    2012-01-01

    Blazars are expected to produce both gamma rays and cosmic rays. Therefore, observed high-energy gamma rays from distant blazars may contain a significant contribution from secondary gamma rays produced along the line of sight by the interactions of cosmic-ray protons with background photons. Unlike the standard models of blazars that consider only the primary photons emitted at the source, models which include the cosmic-ray contribution predict that even ~10 TeV photons should be detectable from distant objects with redshifts as high as z> 0.1. Secondary photons contribute to signals of point sources only if the intergalactic magnetic fields are very small, below ~10 femtogauss, and their detection can be used to set upper bounds on magnetic fields along the line of sight. Secondary gamma rays have distinct spectral and temporal features. We explore the temporal properties of such signals using a semi-analytical formalism and detailed numerical simulations, which account for all the relevant processes, incl...

  13. Electron-mediated nuclear-spin interactions between distant nitrogen-vacancy centers.

    Science.gov (United States)

    Bermudez, A; Jelezko, F; Plenio, M B; Retzker, A

    2011-10-07

    We propose a scheme enabling controlled quantum coherent interactions between separated nitrogen-vacancy centers in diamond in the presence of strong magnetic fluctuations. The proposed scheme couples nuclear qubits employing the magnetic dipole-dipole interaction between the electron spins and, crucially, benefits from the suppression of the effect of environmental magnetic field fluctuations thanks to a strong microwave driving. This scheme provides a basic building block for a full-scale quantum-information processor or quantum simulator based on solid-state technology.

  14. Electron-Mediated Nuclear-Spin Interactions Between Distant NV Centers

    CERN Document Server

    Bermudez, A; Plenio, M B; Retzker, A

    2011-01-01

    We propose a scheme enabling controlled quantum coherent interactions between separated nitrogen-vacancy centers in diamond in the presence of strong magnetic fluctuations. The proposed scheme couples nuclear qubits employing the magnetic dipole-dipole interaction between the electron spins and, crucially, benefits from the suppression of the effect of environmental magnetic field fluctuations thanks to a strong microwave driving. This scheme provides a basic building block for a full-scale quantum information processor or quantum simulator based on solid-state technology.

  15. Epidemic phase and the site percolation with distant-neighbor interactions

    Science.gov (United States)

    dos Santos, C. B.; Barbin, D.; Caliri, A.

    1998-01-01

    A generalized site percolation model is used to construct an analogy with the epidemic problem, involving spatial coordinates. Epidemic phase and concepts like herd immunity are analyzed in terms of connectivity in a 2D square lattice. The epidemic model used in this work considers a specific interaction topology that includes up to the fifth-nearest neighbors. The results, obtained by Monte Carlo simulation, emphasize the meaning of the spatial coordinates and are illustrated by an epidemic/non-epidemic phase diagram.

  16. Interaction-Triggered Star Formation in Distant Galaxies and the Role of Mergers in Galaxy Evolution

    CERN Document Server

    Lin, Lihwai

    2009-01-01

    The evolution of galaxy merger rates and its impact on galaxy properties have been studied intensively over the last decade. It becomes clear now that various types of mergers, i.e. gas-rich (wet), gas-poor (dry), or mixed mergers, affect the merger products in different ways. The epoch when each type of merger dominates also differs. In this talk, I review the recent progress on the measurements of galaxy merger rates out to z ~ 3 and the level of interaction-triggered star formation using large samples from various redshift surveys. These results provide insights to the importance of mergers in the mass assembly history of galaxies and in the evolution of galaxy properties. I also present new results in characterizing the environment of galaxy mergers, and discuss their implications in the built up of red-sequence galaxies.

  17. Protein-binding RNA aptamers affect molecular interactions distantly from their binding sites

    DEFF Research Database (Denmark)

    Dupont, Daniel M; Thuesen, Cathrine K; Bøtkjær, Kenneth A;

    2015-01-01

    Nucleic acid aptamer selection is a powerful strategy for the development of regulatory agents for molecular intervention. Accordingly, aptamers have proven their diligence in the intervention with serine protease activities, which play important roles in physiology and pathophysiology. Nonetheless...... potential, both binding to the serine protease urokinase-type plasminogen activator (uPA). We determine the subsequent impact of aptamer binding on the well-established molecular interactions (plasmin, PAI-1, uPAR, and LRP-1A) controlling uPA activities. One of the aptamers (upanap-126) binds to the area...... around the C-terminal α-helix in pro-uPA, while the other aptamer (upanap-12) binds to both the β-hairpin of the growth factor domain and the kringle domain of uPA. Based on the mapping studies, combined with data from small-angle X-ray scattering analysis, we construct a model for the upanap-12:pro...

  18. Group tele-immersion:enabling natural interactions between groups at distant sites.

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Christine L. (Sandia National Laboratories, Livermore, CA); Stewart, Corbin (Sandia National Laboratories, Livermore, CA); Nashel, Andrew (University of North Carolina at Chapel Hill, Chapel Hill, NC)

    2005-08-01

    We present techniques and a system for synthesizing views for video teleconferencing between small groups. In place of replicating one-to-one systems for each pair of users, we create a single unified display of the remote group. Instead of performing dense 3D scene computation, we use more cameras and trade-off storage and hardware for computation. While it is expensive to directly capture a scene from all possible viewpoints, we have observed that the participants viewpoints usually remain at a constant height (eye level) during video teleconferencing. Therefore, we can restrict the possible viewpoint to be within a virtual plane without sacrificing much of the realism, and in cloning so we significantly reduce the number of required cameras. Based on this observation, we have developed a technique that uses light-field style rendering to guarantee the quality of the synthesized views, using a linear array of cameras with a life-sized, projected display. Our full-duplex prototype system between Sandia National Laboratories, California and the University of North Carolina at Chapel Hill has been able to synthesize photo-realistic views at interactive rates, and has been used to video conference during regular meetings between the sites.

  19. Distant Relations

    DEFF Research Database (Denmark)

    Søndergaard, Morten

    2011-01-01

    contribute to and learn from entrepreneurship research. In a number of workshops sponsored by the Knowledge Foundation and the Bank of Sweden Tercentenary Foundation, a group of international scholars, practicing artists, and representatives of funding organizations have addressed issues such as opportunity......) Entrepreneurship on the art arena - An ecological perspective (Mikael Scherdin and Ivo Zander) Distant relations - Art practice in a global culture (Morten Søndergaard) Art entrepreneurship - A commentary (Daved Barry) Summary and policy implications (Mikael Scherdin and Ivo Zander)...

  20. Distant Relations

    DEFF Research Database (Denmark)

    Søndergaard, Morten

    2011-01-01

    Art EntrepreneurshipIvo Zander Mikael Scherdin This project is funded and sponsored by the Knowledge Foundation, the Bank of Sweden Tercentenary Foundation, and the Department of Business Studies, Uppsala University2008-2009This cutting edge project asks what art and artistic processes can contri......) Entrepreneurship on the art arena - An ecological perspective (Mikael Scherdin and Ivo Zander) Distant relations - Art practice in a global culture (Morten Søndergaard) Art entrepreneurship - A commentary (Daved Barry) Summary and policy implications (Mikael Scherdin and Ivo Zander)...

  1. Distant Relations

    DEFF Research Database (Denmark)

    Bülow, Anne Marie; Lee, Joyce y. H.; Panteli, Niki

    2016-01-01

    This article explores the role of email in the ambiguous circumstances of an established international partnership that is developing into competition. Using the naturally occurring interaction of a longitudinal ethnographic study, we study the ensuing task and relationship conflicts through...... the communication medium. Results show that the conflict is facilitated by email, not as an unfortunate side-effect but as a strategic choice of distance, partly for passive protection but also for active control of the interaction. We use the results to chart the multiple situated identities of the communicators...

  2. Distant Neighbors

    OpenAIRE

    Cole, Alexander

    2014-01-01

    The co-location of industry in agglomerations of similar and related firms is one of the salient features of the contemporary global economy. Over the last thirty years, a large body of theory and case-literature has addressed this phenomenon and sought to understand the advantages that accrue when industries are spatially clustered. Contemporary scholars in this tradition have focused on the advantages of face-toface interaction and the access to spatially sticky information i...

  3. Coexisting/Coexpressing Genomic Libraries (CoGeL) identify interactions among distantly located genetic loci for developing complex microbial phenotypes.

    Science.gov (United States)

    Nicolaou, Sergios A; Gaida, Stefan M; Papoutsakis, Eleftherios T

    2011-12-01

    In engineering novel microbial strains for biotechnological applications, beyond a priori identifiable pathways to be engineered, it is becoming increasingly important to develop complex, ill-defined cellular phenotypes. One approach is to screen genomic or metagenomic libraries to identify genes imparting desirable phenotypes, such as tolerance to stressors or novel catabolic programs. Such libraries are limited by their inability to identify interactions among distant genetic loci. To solve this problem, we constructed plasmid- and fosmid-based Escherichia coli Coexisting/Coexpressing Genomic Libraries (CoGeLs). As a proof of principle, four sets of two genes of the l-lysine biosynthesis pathway distantly located on the E. coli chromosome were knocked out. Upon transformation of these auxotrophs with CoGeLs, cells growing without supplementation were found to harbor library inserts containing the knocked-out genes demonstrating the interaction between the two libraries. CoGeLs were also screened to identify genetic loci that work synergistically to create the considerably more complex acid-tolerance phenotype. CoGeL screening identified combination of genes known to enhance acid tolerance (gadBC operon and adiC), but also identified the novel combination of arcZ and recA that greatly enhanced acid tolerance by 9000-fold. arcZ is a small RNA that we show increases pH tolerance alone and together with recA.

  4. Dynamic screening and electron electron scattering in low-dimensional metallic systems

    Science.gov (United States)

    Silkin, V. M.; Quijada, M.; Muiño, R. Díez; Chulkov, E. V.; Echenique, P. M.

    2007-09-01

    The modification of dynamic screening in the electron-electron interaction in systems with reduced dimensionality and tunable one-particle electronic structure is studied. Two examples of such systems are considered, namely, the adsorbate-induced quantum well states at the Na adlayer covered Cu(1 1 1) surface, and metal clusters of sizes up to few nanometers. The dependence of the electron-electron decay rates on the Na coverage in the former case and on the cluster size in the latter is investigated. The role played by the dynamical screened interaction in such processes is addressed as well.

  5. Development of Interactive and Reflective Learning among Malaysian Online Distant Learners: An ESL Instructor’s Experience

    Directory of Open Access Journals (Sweden)

    Puvaneswary Murugaiah

    2010-10-01

    Full Text Available Technology has brought tremendous advancements in online education, spurring transformations in online pedagogical practices. Online learning in the past was passive, using the traditional teacher-centred approach. However, with the tools available today, it can be active, collaborative, and meaningful. A well-developed task can impel learners to observe, to reflect, to strategize, and to plan their own learning. This paper describes an English as a Second Language (ESL instructor’s attempt to foster interactive and reflective learning among distance learners at a public university in Malaysia, working within the framework proposed by Salmon (2004. The authors found that proper planning and close monitoring of a writing activity that incorporates interactive and reflective learning helped to raise the students’ awareness of their own learning process and consequently helped them to be more responsible for their learning. The students acquired significant cognitive benefits and also valuable practical learning skills through the online discussions. However, there were challenges in carrying out the writing task to promote this form of learning, including students’ professional and family commitments and cultural attitudes as well as communication barriers in the online environment. To address these challenges, the authors recommend the following: ensure tutor guidance, enforce compulsory participation, address technical problems quickly, commence strategic training prior to the beginning of a task, and implement team teaching with each instructor taking on certain roles.

  6. Multiple, distant (40°) in situ observations of a magnetic cloud and a corotating interaction region complex

    Science.gov (United States)

    Farrugia, C. J.; Berdichevsky, D. B.; Möstl, C.; Galvin, A. B.; Leitner, M.; Popecki, M. A.; Simunac, K. D. C.; Opitz, A.; Lavraud, B.; Ogilvie, K. W.; Veronig, A. M.; Temmer, M.; Luhmann, J. G.; Sauvaud, J. A.

    2011-06-01

    We report a comprehensive analysis of in situ observations made by Wind and the STEREO probes (STA, STB) of a complex interaction between a magnetic cloud (MC) and a corotating interaction region (CIR) occurring near the heliospheric current sheet (HCS) on November 19-21, 2007. The probes were separated by 0.7 AU (˜40∘) with a spread in heliographic latitudes (4.8,° 2.2,° and -0.4,° for STB, Wind and STA, respectively). We employ data from the MFI, SWE and 3DP instruments on Wind, and the PLASTIC and IMPACT suites on STEREO. STB, located east of Earth, observed a forward shock followed by signatures of a MC. The MC took the role of the HCS in that the polarity of the interplanetary magnetic field (IMF) on exit was the reverse of that on entry. A passage through a plasma sheet was observed. Along the Sun-Earth line Wind observed a stream interface (SI) between a forward and a reverse shock. A MC, compressed by the CIR, was entrained in this. STA, located 20° to the west of Earth, saw a MC which was not preceded by a shock. A SI trailed the transient. The shocks are examined using various methods and from this it is concluded that the forward shock at Wind—but not at STB—was driven by the MC. Examining the MC by Grad-Shafranov reconstruction, we find evidence of a double-flux rope structure at Wind and STA and possibly also at STB. The orientations are at variance with the notion of a large-scale flux tube being observed at the three spacecraft. We find consistency of this with the directional properties of the solar wind "strahl" electrons. We examine aspects of the geomagnetic response and find a double-dip storm corresponding to the two interplanetary triggers. The minimum Dst phase was prolonged and the geoeffects were intensified due to the interaction. We conclude that while the formation of compound streams is a common feature of interplanetary space, understanding their components when CIRs are involved is a complicated matter needing numerical

  7. Multiple, Distant (40 deg) in situ Observations of a Magnetic Cloud and a Corotating Interaction Region Complex

    Science.gov (United States)

    Farrugia, C. J.; Berdichevsky, D. B.; Moestl, C.; Galvin, A. B.; Leitner, M.; Popecki, M.; Simunac, K. D.; Opitz, A.; Lavraud, B.; Ogilvie, K.; Veronig, A.; Temmer, M.; Luhmann, J. G.; Sauvaud, J.

    2010-12-01

    We report a comprehensive analysis of in situ observations made by Wind and the STEREO probes (STA, STB) of a complex interaction between a magnetic cloud (MC) and a corotating interaction region (CIR) occurring near the heliospheric current sheet (HCS) on November 19-21, 2007. The probes were separated by 0.7 AU (~40 deg) with a spread in heliographic latitudes (4.8, 2.2, and -0.4 deg for STB, Wind and STA, respectively). We employ data from the MFI, SWE and 3DP instruments on Wind, and the PLASTIC and IMPACT suites on STEREO. STB, located east of Earth, observed a forward shock followed by signatures of a MC. The MC took the role of the HCS in that the polarity of the interplanetary magnetic field (IMF) on exit was the reverse of that on entry. A passage through a plasma sheet is observed. Along the Sun-Earth line Wind observed a stream interface (SI) between a forward and a reverse shock. A MC, compressed by the CIR, was entrained in this. STA, located 20 deg to the west of Earth, saw a MC which was not preceded by a shock. A SI trailed the transient. The shocks are examined using various methods and from this it is concluded that the forward shock at Wind - but not at STB - was driven by the MC. Examining the MC by Grad-Shafranov reconstruction, we find evidence of a double-flux rope structure at Wind and STA and possibly also at STB. The orientations are at variance with the notion of a large-scale flux tube being observed at the three spacecraft. We find consistency of this with the directional properties of the solar wind "strahl" electrons. We examine aspects of the geomagnetic response and find a double-dip storm corresponding to the two interplanetary triggers. The minimum Dst phase was prolonged and the geoffects were intensified due to the interaction. We conclude that while the formation of compound streams is a common feature of interplanetary space, understanding their components when CIRs are involved is a complicated matter needing numerical

  8. Electron-electron correlations in square-well quantum dots: direct energy minimization approach.

    Science.gov (United States)

    Goto, Hidekazu; Hirose, Kikuji

    2011-04-01

    Electron-electron correlations in two-dimensional square-well quantum dots are investigated using the direct energy minimization scheme. Searches for groundstate charges and spin configurations are performed with varying the sizes of dots and the number of electrons. For a two-electron system, a standout difference between the configurations with and without counting correlation energy is demonstrated. The emergence and melting of Wigner-molecule-like structures arising from the interplay between the kinetic energy and Coulombic interaction energy are described. Electron-electron correlation energies and addition energy spectra are calculated, and special electron numbers related to peculiar effects of the square well are extracted.

  9. Electron-electron correlations in liquid s-p metals

    CERN Document Server

    Leys, F E

    2003-01-01

    We present calculations for the valence electron-electron structure factor in liquid Mg near freezing, assuming knowledge of the jellium result. On the basis of this, we predict significant corrections to jellium short-range correlations in liquid s-p metals and in particular an increase in the electron-electron contact probability.

  10. Distinguishing attosecond electron-electron scattering and screening in transition metals

    Science.gov (United States)

    Chen, Cong; Tao, Zhensheng; Carr, Adra; Matyba, Piotr; Szilvási, Tibor; Emmerich, Sebastian; Piecuch, Martin; Keller, Mark; Zusin, Dmitriy; Eich, Steffen; Rollinger, Markus; You, Wenjing; Mathias, Stefan; Thumm, Uwe; Mavrikakis, Manos; Aeschlimann, Martin; Oppeneer, Peter M.; Kapteyn, Henry; Murnane, Margaret

    2017-07-01

    Electron-electron interactions are the fastest processes in materials, occurring on femtosecond to attosecond timescales, depending on the electronic band structure of the material and the excitation energy. Such interactions can play a dominant role in light-induced processes such as nano-enhanced plasmonics and catalysis, light harvesting, or phase transitions. However, to date it has not been possible to experimentally distinguish fundamental electron interactions such as scattering and screening. Here, we use sequences of attosecond pulses to directly measure electron-electron interactions in different bands of different materials with both simple and complex Fermi surfaces. By extracting the time delays associated with photoemission we show that the lifetime of photoelectrons from the d band of Cu are longer by ˜100 as compared with those from the same band of Ni. We attribute this to the enhanced electron-electron scattering in the unfilled d band of Ni. Using theoretical modeling, we can extract the contributions of electron-electron scattering and screening in different bands of different materials with both simple and complex Fermi surfaces. Our results also show that screening influences high-energy photoelectrons (≈20 eV) significantly less than low-energy photoelectrons. As a result, high-energy photoelectrons can serve as a direct probe of spin-dependent electron-electron scattering by neglecting screening. This can then be applied to quantifying the contribution of electron interactions and screening to low-energy excitations near the Fermi level. The information derived here provides valuable and unique information for a host of quantum materials.

  11. The importance of the on-site electron-electron interaction for the magnetic coupling in the zigzag spin-chain compound In{sub 2}VO{sub 5}

    Energy Technology Data Exchange (ETDEWEB)

    Wang, H; Schwingenschloegl, U [KAUST, PSE Division, 23955-6900 Thuwal (Saudi Arabia)

    2010-10-20

    We present first-principles electronic structure calculations for the zigzag spin-chain compound In{sub 2}VO{sub 5} using the generalized gradient approximation both with and without inclusion of an on-site Coulomb interaction. It has been proposed that In{sub 2}VO{sub 5} is characterized by itinerant V 3d electrons at high temperature and localized electrons at low temperature. Consequently, it is to be expected that electronic correlations play an important role for the magnetic transition from ferromagnetic to antiferromagnetic exchange around 120 K. In this context, we study the electronic and magnetic properties of a set of possible spin configurations. Our calculations show that inclusion of an on-site Coulomb interaction in fact changes the ground state from ferromagnetic to antiferromagnetic.

  12. The importance of the on-site electron-electron interaction for the magnetic coupling in the zigzag spin-chain compound In{sub 2}VO{sub 5}

    Energy Technology Data Exchange (ETDEWEB)

    Schwingenschloegl, Udo; Wang, Hao [PSE Division, KAUST, 23955-6900 Thuwal (Saudi Arabia)

    2011-07-01

    We present first-principles electronic structure calculations for the zigzag spin-chain compound In{sub 2}VO{sub 5} using the generalized gradient approximation both with and without inclusion of an on-site Coulomb interaction. It has been proposed that In{sub 2}VO{sub 5} is characterized by itinerant V 3d electrons at high temperature and localized electrons at low temperature. Consequently, it is to be expected that electronic correlations play an important role for the magnetic transition from ferromagnetic to antiferromagnetic exchange around 120 K. In this context, we study the electronic and magnetic properties of a set of possible spin configurations. Our calculations show that inclusion of an on-site Coulomb interaction in fact changes the ground state from ferromagnetic to antiferromagnetic.

  13. Two Distantly Spaced Basic Patches in the Flexible Domain of Huntingtin-Interacting Protein 1 (HIP1 Are Essential for the Binding of Clathrin Light Chain

    Directory of Open Access Journals (Sweden)

    Joel A. Ybe

    2009-01-01

    Full Text Available The interaction between HIP family proteins (HIP1 and HIP12/1R and clathrin is fundamental to endocytosis. We used circular dichroism (CD to study the stability of an HIP1 subfragment (aa468-530 that is splayed open. CD thermal melts show HIP1 468-530 is only stable at low temperatures, but this HIP1 fragment contains a structural unit that does not melt out even at 83C∘. We then created HIP1 mutants to probe our hypothesis that a short hydrophobic path in the opened region is the binding site for clathrin light chain. We found that the binding of hub/LCb was sensitive to mutating two distantly separated basic residues (K474 and K494. The basic patches marked by K474 and K494 are conserved in HIP12/1R. The lack of conservation in sla2p (S. cerevisiae, HIP1 from D. melanogaster, and HIP1 homolog ZK370.3 from C. elegans implies the binding of HIP1 and HIP1 homologs to clathrin light chain may be different in these organisms.

  14. XMM-Newton Observation of a Distant X-ray Selected Cluster of Galaxies at z=1.26 with Possible Cluster Interaction

    CERN Document Server

    Hashimoto, Y; Arnaud, M; Rosati, P; Miyaji, T; Hashimoto, Yasuhiro; Hasinger, Guenther; Arnaud, Monique; Rosati, Piero; Miyaji, Takamitsu

    2002-01-01

    We report on the XMM-Newton (XMM) observation of RXJ1053.7+5735, one of the most distant (z = 1.26) X-ray selected clusters of galaxies, which also shows an unusual double-lobed X-ray morphology, indicative of possible cluster-cluster interaction. The cluster was discovered during our ROSAT deep pointings in the direction of the Lockman Hole. The XMM observations were performed with the European Photon Imaging Camera (EPIC) during the performance verification phase. Total effective exposure time was ~ 100 ksec. The best fit temperature based on a simultaneous fit of spectra from the all EPIC cameras is 4.9(+1.5/-0.9) keV. Metallicity is poorly constrained even using the joint fit of all spectra, with an upper limit on the iron abundance of 0.62 solar. Using the best fit model parameters, we derived a bolometric luminosity of L(bol) = 3.4x10^44 h_{50}^-2 erg /s. Despite the fact that it was observed at fairly large off-axis angle, the temperature errors are much smaller compared with those of typical measureme...

  15. [Distant mental influence on living organisms].

    Science.gov (United States)

    Bonilla, Ernesto

    2013-12-01

    This article reviews studies of distant mental influence on living organisms, including mental suggestions of sleeping and awakening, mental influence at long distances, mental interactions with remote biological systems, mental effects on physiological activity and the sense of being stared at. Significant effects of distant mental influence have been shown in several randomized controlled trials in humans, animals, plants, bacteria and cells in the laboratory. Although distant mental influence on living organisms appears to contradict our ordinary sense of reality and the laws defined by conventional science, several hypotheses have been proposed to explain the observed effects; they include skeptical, signal transfer, field, multidimensional space/time and quantum mechanics hypotheses. In conclusion, as the progress of physics continues to expand our comprehension of reality, a rational explanation for distant mind-matter interaction will emerge and, as history has shown repeatedly, the supernatural events will evolve into paranormal and then, into normal ones, as the scientific frontiers expand.

  16. Observations of Distant Clusters

    Science.gov (United States)

    Donahue, Megan

    2004-01-01

    The is the proceedings and papers supported by the LTSA grant: Homer, D. J.\\& Donahue, M. 2003, in "The Emergence of Cosmic Structure": 13'h Astrophysics Conference Proceedings, Vol. 666,3 1 1-3 14, (AIP). Baumgartner, W. H., Loewenstein, M., Horner, D. J., Mushotzky, R. F. 2003, HEAD- AAS, 35.3503. Homer, D. J. , Donahue, M., Voit G. M. 2003, HEAD-AAS, 35.1309. Nowak, M. A., Smith, B., Donahue, M., Stocke, J. 2003, HEAD-AAS, 35.1316. Scott, D., Borys, C., Chapman, S. C., Donahue, M., Fahlman, G. G., Halpem, M. Newbury, P. 2002, AAS, 128.01. Jones, L. R. et al. 2002, A new era in cosmology, ASP Conference Proceedings, Vol. 283, p. 223 Donahue, M., Daly, R. A., Homer, D. J. 2003, ApJ, 584, 643, Constraints on the Cluster Environments and Hotspot magnetic field strengths for radio sources 3280 and 3254. Donahue, M., et al. 2003, ApJ, 598, 190. The mass, baryonic fraction, and x-ray temperature of the luminous, high-redshift cluster of galaxies MS045 1.6-0305 Perlman, E. S. et al. 2002, ApJS, 140, 256. Smith, B. J., Nowak, M., Donahue, M., Stocke, J. 2003, AJ, 126, 1763. Chandra Observations of the Interacting NGC44 10 Group of Galaxies. Postman, M., Lauer, T. R., Oegerle, W., Donahue, M. 2002, ApJ, 579, 93. The KPNO/deep-range cluster survey I. The catalog and space density of intermediate-redshift clusters. Molnar, S. M., Hughes, J. P., Donahue, M., Joy, M. 2002, ApJ, 573, L91, Chandra Observations of Unresolved X-Ray Sources around Two Clusters of Galaxies. Donahue, M., Mack, J., 2002 NewAR, 46, 155, HST NIcmos and WFPC2 observations of molecular hydrogen and dust around cooling flows. Koekemoer, A. M. et al. 2002 NewAR, 46, 149, Interactions between the A2597 central radio source and dense gas host galaxy. Donahue, M. et al. 2002 ApJ, 569,689, Distant cluster hunting II.

  17. Electron-electron bound states in parity-preserving QED{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Belich, H.; Helayel-Neto, J.A. [Universidade Catolica do Petropolis, RJ (Brazil). Grupo de Fisica Teorica]|[Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil). Coordenacao de Teoria de Campos e Particulas; Cima, O.M. del [Universidade Catolica do Petropolis, RJ (Brazil). Grupo de Fisica Teorica; Ferreira Junior, M.M. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil). Coordenacao de Teoria de Campos e Particulas]|[Maranhao Univ., Sao Luis, MA (Brazil). Dept. de Fisica

    2002-04-01

    By considering the Higgs mechanism in the framework of a parity-preserving Planar Quantum Electrodynamics, one shows that an attractive electron-electron interaction may dominate. The e{sup -}e{sup -} interaction potential emerges as the non-relativistic limit of the Moeller scattering amplitude and it results attractive with a suitable choice of parameters. Numerically values of the e{sup -}e{sup -} binding energy are obtained by solving the two-dimensional Schroedinger equation. The existence of bound states is a strong indicative that this model may be adopted to address the pairing mechanism of high-T{sub c} superconductivity. (author)

  18. Visualization of Distance Distribution from Pulsed Double Electron-Electron Resonance Data

    Energy Technology Data Exchange (ETDEWEB)

    Bowman, Michael K.; Maryasov, Alexander G.; Kim, Nak-Kyoon; DeRose, Victoria J.

    2004-01-01

    Double electron-electron resonance (DEER), also known as pulsed electron-electron double resonance (PELDOR), is a time-domain electron paramagnetic resonance method that can measure the weak dipole-dipole interactions between unpaired electrons. DEER has been applied to discrete pairs of free radicals in biological macromolecules and to clusters containing small numbers of free radicals in polymers and irradiated materials. The goal of such work is to determine the distance or distribution of distances between radicals, which is an underdetermined problem. That is, the spectrum of dipolar interactions can be readily calculated for any distribution of free radicals, but there are many, quite different distributions of radicals that could produce the same experimental dipolar spectrum. This paper describes two methods that are useful for approximating the distance distributions for the large subset of cases in which the mutual orientations of the free radicals are uncorrelated and the width of the distribution is more than a few percent of its mean. The first method relies on a coordinate transformation and is parameter free, while the second is based on iterative least-squares with Tikhonov regularization. Both methods are useful in DEER studies of spin labeled biomolecules containing more than two labels.

  19. Controlled by Distant Explosions

    Science.gov (United States)

    2007-03-01

    VLT Automatically Takes Detailed Spectra of Gamma-Ray Burst Afterglows Only Minutes After Discovery A time-series of high-resolution spectra in the optical and ultraviolet has twice been obtained just a few minutes after the detection of a gamma-ray bust explosion in a distant galaxy. The international team of astronomers responsible for these observations derived new conclusive evidence about the nature of the surroundings of these powerful explosions linked to the death of massive stars. At 11:08 pm on 17 April 2006, an alarm rang in the Control Room of ESO's Very Large Telescope on Paranal, Chile. Fortunately, it did not announce any catastrophe on the mountain, nor with one of the world's largest telescopes. Instead, it signalled the doom of a massive star, 9.3 billion light-years away, whose final scream of agony - a powerful burst of gamma rays - had been recorded by the Swift satellite only two minutes earlier. The alarm was triggered by the activation of the VLT Rapid Response Mode, a novel system that allows for robotic observations without any human intervention, except for the alignment of the spectrograph slit. ESO PR Photo 17a/07 ESO PR Photo 17a/07 Triggered by an Explosion Starting less than 10 minutes after the Swift detection, a series of spectra of increasing integration times (3, 5, 10, 20, 40 and 80 minutes) were taken with the Ultraviolet and Visual Echelle Spectrograph (UVES), mounted on Kueyen, the second Unit Telescope of the VLT. "With the Rapid Response Mode, the VLT is directly controlled by a distant explosion," said ESO astronomer Paul Vreeswijk, who requested the observations and is lead-author of the paper reporting the results. "All I really had to do, once I was informed of the gamma-ray burst detection, was to phone the staff astronomers at the Paranal Observatory, Stefano Bagnulo and Stan Stefl, to check that everything was fine." The first spectrum of this time series was the quickest ever taken of a gamma-ray burst afterglow

  20. Modulation scheme for electron-electron double resonance spectroscopy

    Science.gov (United States)

    Mehlkopf, A. F.; Kuiper, F. G.; Smidt, J.; Tiggelman, T. A.

    1983-06-01

    A modulation scheme for electron-electron double resonance (ELDOR) spectrometers is presented. With this scheme an optimum stabilization signal for locking the pump microwave generator to the pumped electron paramagnetic resonance (EPR) line is generated. A separate pump power level and a separate magnetic field modulation amplitude are used for the purpose of locking. In general, such a modulation scheme introduces false ELDOR lines. These false lines disturb the real ELDOR signals, or introduce an ELDOR signal in the absence of any communication between the observed EPR line and the pumped EPR line. With the described modulation scheme the frequencies of the false ELDOR signals are limited to even multiples of the frequency of the wanted ELDOR signals. This makes a suppression of the false ELDOR lines easy.

  1. Transient optical response of ultrafast nonequilibrium excited metals: Effects of electron-electron contribution to collisional absorption

    CERN Document Server

    Colombier, Jean-Philippe; Audouard, Eric; Stoian, Razvan

    2008-01-01

    Approaching energy coupling in laser-irradiated metals, we point out the role of electron-electron collision as an efficient control factor for ultrafast optical absorption. The high degree of laser-induced electron-ion nonequilibrium drives a complex absorption pattern with consequences on the transient optical properties. Consequently, high electronic temperatures determine largely the collision frequency and establish a transition between absorptive regimes in solid and plasma phases. In particular, taking into account umklapp electron-electron collisions, we performed hydrodynamic simulations of the laser-matter interaction to calculate laser energy deposition during the electron-ion nonequilibrium stage and subsequent matter transformation phases. We observe strong correlations between optical and thermodynamic properties according to the experimental situations. A suitable connection between solid and plasma regimes is chosen in accordance with models that describe the behavior in extreme, asymptotic re...

  2. Velocity Fields of Distant Galaxies with FORS2

    NARCIS (Netherlands)

    Ziegler, Bodo; Kutdemir, Elif; Da Rocha, Cristiano; Böhm, Asmus; Kapferer, Wolfgang; Kuntschner, Harald; Peletier, R.F.; Schindler, Sabine; Verdugo, Miguel

    2009-01-01

    We describe a method of obtaining two-dimensional velocity fields of distant, faint and small, emission-line galaxies efficiently with FORS2 at the VLT. The fields are examined for kinematic substructure to identify possible interaction processes. Numerical simulations of tidal interactions and ram

  3. Gaseous activity of distant comets

    Science.gov (United States)

    Womack, Maria; Sarid, Gal; Wierzchos, Kacper

    2016-10-01

    The activity of most comets within 3AU of the Sun is dominated by the sublimation of frozen water, the most abundant ice in comets. Some comets, however, are active well beyond the water-ice sublimation limit. Studying distantly active comets provides valuable opportunities to explore primitive bodies when water-ice sublimation is largely dormant, which is the case for most of a comet's lifetime. Beyond 4 AU, super-volatiles such as CO or CO2 are thought to play a major role in driving observed activity. Carbon monoxide is of special interest because it is a major contributor to comae and has a very low sublimation temperature. Three bodies dominate the observational record and modeling efforts for distantly active small bodies: the long-period comet C/1995 O1 Hale-Bopp and the short-period comets (with centaur orbits) 29P/Schwassmann Wachmann 1 and 2060 Chiron. Hale-Bopp's long-period orbit means it has experienced very little solar heating in its lifetime and is analogous to dynamically new comets making their first approach to the Sun. Because Chiron and 29P have much smaller orbits closer to the Sun, they have experienced much more thermal processing than Hale-Bopp and this is expected to have changed their chemical composition from their original state. We point out that the observed CO production rates and line-widths in these three distantly active objects are consistent with each other when adjusted for heliocentric distance. This is particularly interesting for Hale-Bopp and 29P, which have approximately the same radius. The consistent CO production rates may point to a similar CO release mechanism in these objects. We also discuss how observed radio line profiles support that the development and sublimation of icy grains in the coma at about 5-6 AU is probably a common feature in distantly active comets, and an important source of other volatiles within 6 AU, including H2O, HCN, CH3OH, and H2CO.

  4. Islam y Occidente: Vecinos distantes

    Directory of Open Access Journals (Sweden)

    Zidane Zeraoui

    2003-01-01

    Full Text Available El artículo “Islam y Occidente: vecinos distantes” busca analizar la incomprensión mutua existente entre dos civilizaciones cercanas geográfica e históricamente hablando, pero al mismo tiempo alejadas en su relación actual. Los conflictos que han opuesto el mundo islámico al mundo occidental en los tiempos recientes ha creado un rechazo mutuo en muchos sectores tanto de la sociedad cristiana como de la musulmana.

  5. Electron-electron bound states in Maxwell-Chern-Simons-Proca QED{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Belich, H.; Helayel-Neto, J.A. [Grupo de Fisica Teorica Jose Leite Lopes, Petropolis, RJ (Brazil)]|[Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil). Coordenacao de Teoria de Campos e Particulas]. E-mail: belich@cbpf.br; helayel@gft.ucp.br; Del Cima, O.M. [Grupo de Fisica Teorica Jose Leite Lopes, Petropolis, RJ (Brazil)]. E-mail: delcima@gft.ucp.br; Ferreira, M.M. Jr. [Grupo de Fisica Teorica Jose Leite Lopes, Petropolis, RJ (Brazil)]|[Maranhao Univ., Sao Luis, MA (Brazil). Dept. de Fisica]. E-mail: manojr@cbpf.br

    2002-10-01

    We start from a parity-breaking MCS QED{sub 3} model with spontaneous breaking of the gauge symmetry as a framework for evaluation of the electron-electron interaction potential and for attainment of numerical values for the e{sup -}e{sup -} - bound state. Three expressions (V{sub eff{down_arrow}}{sub {down_arrow}}, V{sub eff{down_arrow}}{sub {up_arrow}}, V{sub eff{down_arrow}}{sub {down_arrow}}) are obtained according to the polarization state of the scattered electrons. In an energy scale compatible with condensed matter electronic excitations, these potentials become degenerated. The resulting potential is implemented in the Schroedinger equation and the variational method is applied to carry out the electronic binding energy. The resulting binding energies in the scale of 10-100 meV and a correlation length in the scale of 10 - 30 Angstrom are possible indications that the MCS-QED{sub 3} model adopted may be suitable to address an eventual case of e{sup -}e{sup -} pairing in the presence of parity-symmetry breakdown. The data analyzed here suggest an energy scale of 10-100 meV to fix the breaking of the U(1)-symmetry. (author)

  6. On the basis set convergence of electron-electron entanglement measures: helium-like systems.

    Science.gov (United States)

    Hofer, Thomas S

    2013-01-01

    A systematic investigation of three different electron-electron entanglement measures, namely the von Neumann, the linear and the occupation number entropy at full configuration interaction level has been performed for the four helium-like systems hydride, helium, Li(+) and Be(2+) using a large number of different basis sets. The convergence behavior of the resulting energies and entropies revealed that the latter do in general not show the expected strictly monotonic increase upon increase of the one-electron basis. Overall, the three different entanglement measures show good agreement among each other, the largest deviations being observed for small basis sets. The data clearly demonstrates that it is important to consider the nature of the chemical system when investigating entanglement phenomena in the framework of Gaussian type basis sets: while in case of hydride the use of augmentation functions is crucial, the application of core functions greatly improves the accuracy in case of cationic systems such as Li(+) and Be(2+). In addition, numerical derivatives of the entanglement measures with respect to the nucleic charge have been determined, which proved to be a very sensitive probe of the convergence leading to qualitatively wrong results (i.e., the wrong sign) if too small basis sets are used.

  7. On the basis set convergence of electron-electron entanglement measures: helium-like systems

    Directory of Open Access Journals (Sweden)

    Thomas S. Hofer

    2013-11-01

    Full Text Available A systematic investigation of three different electron--electron entanglement measures, namely the von Neumann, the linear and the occupation number entropy at full configuration interaction level has been performed for the four helium-like systems hydride, helium, lithium(I and beryllium(II using a large number of different basis sets. The convergence behaviour of the resulting energies and entropies was revealed that the latter do in general not show monotonic convergence upon increase of the one--electron basis. Overall, the three different entanglement measures show good agreement among each other, the largest deviations being observed for small basis sets. The data clearly demonstrates that it is important to consider the nature of the chemical system when investigating entanglement phenomena in the framework of Gaussian type basis sets: while in case of hydride the use of augmentation functions is crucial, the application of core functions greatly improves the accuracy in case of cationic systems such as lithium(I and beryllium(II.In addition, numerical derivatives of the entanglement measures with respect to the nucleic charge have been determined, which proved to be a very sensitive probe of the convergence leading to qualitatively wrong results if inadequate basis sets are used.

  8. Galactic Teamwork Makes Distant Bubbles

    Science.gov (United States)

    Kohler, Susanna

    2016-03-01

    During the period of reionization that followed the dark ages of our universe, hydrogen was transformed from a neutral state, which is opaque to radiation, to an ionized one, which is transparent to radiation. But what generated the initial ionizing radiation? The recent discovery of multiple distant galaxies offers evidence for how this process occurred.Two Distant GalaxiesWe believe reionization occurred somewhere between a redshift of z = 6 and 7, because Ly-emitting galaxies drop out at roughly this redshift. Beyond this distance, were generally unable to see the light from these galaxies, because the universe is no longer transparent to their emission. This is not always the case, however: if a bubble of ionized gas exists around a distant galaxy, the radiation can escape, allowing us to see the galaxy.This is true of two recently-discovered Ly-emitting galaxies, confirmed to be at a redshift of z~7 and located near one another in a region known as the Bremer Deep Field. The fact that were able to see the radiation from these galaxies means that they are in an ionized HII region presumably one of the earlier regions to have become reionized in the universe.But on their own, neither of these galaxies is capable of generating an ionized bubble large enough for their light to escape. So what ionized the region around them, and what does this mean for our understanding of how reionization occurred in the universe?A Little Help From FriendsLocation in different filters of the objects in the Hubble Bremer Deep Field catalog. The z~7 selection region is outlined by the grey box. BDF-521 and BDF-3299 were the two originally discovered galaxies; the remaining red markers indicate the additional six galaxies discovered in the same region. [Castellano et al. 2016]A team of scientists led by Marco Castellano (Rome Observatory, INAF) investigated the possibility that there are other, faint galaxies near these two that have helped to ionize the region. Performing a survey

  9. Modeling of electron-electron collisions for particle-in-cell simulations

    Energy Technology Data Exchange (ETDEWEB)

    Andrea, D. d' ; Munz, C.D.; Schneider, R.

    2006-09-15

    The modeling of the physics of pulsed plasma thrusters requires the numerical solution of the Boltzmann equation for rarefied plasma flows where continuum assumptions fail. To tackle this challenging task, a cooperation between several institutes has been formed with the goal to develop a hybrid code based on Particle-In-Cell and Direct Simulation Monte Carlo techniques. These development activities are bundled in the project ''Numerische Simulation und Auslegung eines instationaeren gepulsten magnetoplasmadynamischen Triebwerks fuer eine Mondsonde'' which is funded by the Landesstiftung Baden-Wuerttemberg within the subject area ''Modellierung und Simulation auf Hochleistungscomputern''. In the frame of this project, the IHM is in charge to develop suitable physical-mathematical and numerical models to include charged particle collisions into the simulation. which can significantly affect the Parameters of such plasma devices. The intention of the present report is to introduce the Fokker-Planck approach for electron-electron interaction in Standard charged particle simulations. where the impact Parameter is usually large resulting in a small deflection angle. The theoretical and applicative framework is discussed in detail paying particular attention to the Particle-In-Cell approach in velocity space. a new technique which allows the self-consistent computation of the friction and diffusion coefficients arising from the Fokker-Planck treatment of collisions. These velocity-dependent coefficients thernselves are responsible for the change in velocity of the simulation particles, which is determined by the numerical solution of a Langevin-type equation. Simulation results for typical numerical experiments computed with the new developed Fokker-Planck solver are presented. demonstrating the quality. property and reliability of the applied numerical methods. (orig.)

  10. A simple approach for electron-electron scattering in nonequilibrium Green's function simulations (Conference Presentation)

    Science.gov (United States)

    Winge, David O.; Franckie, Martin; Verozzi, Claudio; Wacker, Andreas; Pereira, Mauro F.

    2016-10-01

    Regardless of all the success of Mid Infrared Quantum Cascade Lasers (QCLs), they still do not operate at room temperature in the THz range. The main temperature degrading mechanism for THz QCLs is not known in time of writing this abstract and it is still a topic of debate by the community [S. Khanal et al, J. Opt. 16 094001, 2014]. This is a challenge to theory and it is crucial to treat all possible scattering channels with the same mathematical footing. A summary of different methods for simulating these structures is found in [C. Jirauschek et al, Appl. Phys. Rev. 1 011307, 2014]. In this work we include and study the effects of electron-electron scattering via the Single Plasmon Pole Approximation (SPPA). In this approximation we capture both the static limit as well as dynamic effects. This gives an energy dependent (non-local in time) interaction beyond the Hartree-Fock approximation. This has been studied in a similar model with promising results [T. Schmielau and M.F. Pereira, Appl. Phys. Lett. 95 231111, 2009], and with this work we want to adapt the idea into the model described in Ref. [A. Wacker et a, IEEE Journal of Sel. Top. in Quantum Electron.,19 1200611, 2013]. We start by summarizing the theory underlying the SPPA and we show how it is implemented in the context of our formalism, by showing good agreement with the results for a four well quantum cascade laser [M. Amanti et al, New J. Phys. 11 125022, 2009].

  11. Finding Distant Galactic HII Regions

    CERN Document Server

    Anderson, L D; Johnstone, B M; Bania, T M; Balser, Dana S; Wenger, Trey V; Cunningham, V

    2015-01-01

    The WISE Catalog of Galactic HII Regions contains $\\sim2000$ HII region candidates lacking ionized gas spectroscopic observations. All candidates have the characteristic HII region mid-infrared morphology of WISE $12\\,\\,\\mu\\,m$ emission surrounding $22\\,\\mu\\,m$ emission, and additionally have detected radio continuum emission. We here report Green Bank Telescope (GBT) hydrogen radio recombination line (RRL) and radio continuum detections at X-band (9GHz; 3cm) of 302 WISE HII region candidates (out of 324 targets observed) in the zone $225^{\\circ} > l > -20^{\\circ}$, $|b| \\le 6^{\\circ}$. Here we extend the sky coverage of our HII region Discovery Survey (HRDS), which now contains nearly 800 HII regions distributed across the entire northern sky. We provide LSR velocities for the 302 detections and kinematic distances for 131 of these. Of the 302 new detections, five have ($l, b, v$) coordinates consistent with the Outer Scutum-Centaurus Arm (OSC), the most distant molecular spiral arm of the Milky Way. Due to ...

  12. CO in distantly active comets

    CERN Document Server

    Womack, Maria; Wierzchos, Kacper

    2016-01-01

    Activity of most comets near the Sun is dominated by sublimation of frozen water, the most abundant ice in comets. Some comets, however, are active well beyond the water-ice sublimation limit of ~3 AU. Three bodies dominate the observational record and modeling efforts for distantly active comets: the long-period comet C/1995 O1 Hale-Bopp and the short-period comets (with Centaur orbits) 29P/Schwassmann Wachmann 1 and 2060 Chiron. We summarize what is known about these three objects emphasizing their gaseous comae. We calculate their CN/CO and CO2/CO production rate ratios from the literature and discuss implications. Using our own data we derive CO production rates for all three objects, in order to examine a correlation between gas production and different orbital histories and/or size. We find that orbital history does not appear to play a significant role in explaining 29P's CO production rates. 29P outproduces Hale-Bopp at the same heliocentric distance, even though it has been subjected to much more sol...

  13. Electron-electron scattering in linear transport in two-dimensional systems

    DEFF Research Database (Denmark)

    Hu, Ben Yu-Kuang; Flensberg, Karsten

    1996-01-01

    We describe a method for numerically incorporating electron-electron scattering in quantum wells for small deviations of the distribution function from equilibrium, within the framework of the Boltzmann equation. For a given temperature T and density n, a symmetric matrix needs to be evaluated only...... once, and henceforth it can be used to describe electron-electron scattering in any Boltzmann equation linear-response calculation for that particular T and n. Using this method, we calculate the distribution function and mobility for electrons in a quantum well, including full finite...

  14. CO in Distantly Active Comets

    Science.gov (United States)

    Womack, M.; Sarid, G.; Wierzchos, K.

    2017-03-01

    The activity of most comets near the Sun is dominated by the sublimation of frozen water, the most abundant ice in comets. Some comets, however, are active well beyond the water-ice sublimation limit of ∼3 au. Three bodies dominate the observational record and modeling efforts for distantly active comets: the long-period comet C/1995 O1 (Hale-Bopp), and the short-period comets (with Centaur orbits) 29P/Schwassmann-Wachmann 1 and 2060 Chiron. We summarize what is known about these three objects with an emphasis on their gaseous comae. We calculate their CN/CO and CO2/CO production rate ratios from the literature and discuss implications, such as HCN and CO2 outgassing are not significant contributors to their comae. Using our own data we derive CO production rates, Q(CO), for all three objects to examine whether there is a correlation between gas production and different orbital histories and/or size. The CO measurements of Hale-Bopp (4–11 AU) and 29P are consistent with a nominal production rate of Q(CO) = 3.5 × 1029 r‑2 superimposed with sporadic outbursts. The similarity of Hale-Bopp CO production rates for pre- and post-perihelion suggests that thermal inertia was not very important and therefore most of the activity is at or near the surface of the comet. We further examine the applicability of existing models in explaining the systematic behavior of our small sample. We find that orbital history does not appear to play a significant role in explaining 29P’s CO production rates. 29P outproduces Hale-Bopp at the same heliocentric distance, even though it has been subjected to much more solar heating. Previous modeling work on such objects predicts that 29P should have been devolatilized over a fresher comet like Hale-Bopp. This may point to 29P having a different orbital history than current models predict, with its current orbit acquired more recently. On the other hand, Chiron’s CO measurements are consistent with it being significantly depleted

  15. Density-functional calculations of transport properties in the nondegenerate limit and the role of electron-electron scattering

    Science.gov (United States)

    Desjarlais, Michael P.; Scullard, Christian R.; Benedict, Lorin X.; Whitley, Heather D.; Redmer, Ronald

    2017-03-01

    We compute electrical and thermal conductivities of hydrogen plasmas in the nondegenerate regime using Kohn-Sham density functional theory (DFT) and an application of the Kubo-Greenwood response formula, and demonstrate that for thermal conductivity, the mean-field treatment of the electron-electron (e-e) interaction therein is insufficient to reproduce the weak-coupling limit obtained by plasma kinetic theories. An explicit e-e scattering correction to the DFT is posited by appealing to Matthiessen's Rule and the results of our computations of conductivities with the quantum Lenard-Balescu (QLB) equation. Further motivation of our correction is provided by an argument arising from the Zubarev quantum kinetic theory approach. Significant emphasis is placed on our efforts to produce properly converged results for plasma transport using Kohn-Sham DFT, so that an accurate assessment of the importance and efficacy of our e-e scattering corrections to the thermal conductivity can be made.

  16. Electron-Electron Luminosity in the Next Linear COLLIDER—A Preliminary Study

    Science.gov (United States)

    Zimmermann, F.; Thompson, K. A.; Helm, R. H.

    In this paper, we discuss some operational aspects of electron-electron collisions at the Next Linear Collider (NLC) and estimate the luminosity attainable in such a machine. We also consider the use of two future technologies which could simplify the operation and improve the luminosity in an e-e- collider: polarized rf guns and plasma lenses.

  17. Efficient computation of electron-electron bremsstrahlung emission in a hot thermal plasma

    Science.gov (United States)

    Haug, E.

    1989-07-01

    A formula for the cross section of electron-electron bremsstrahlung (EEB) in the center-of-mass system is used to calculate the spectrum of EEB in a hot thermal plasma as well as the total rate of energy loss due to EEB with a minimum amount of computing time.

  18. Spin decoherence in n-type GaAs: The effectiveness of the third-body rejection method for electron-electron scattering

    Energy Technology Data Exchange (ETDEWEB)

    Marchetti, Gionni, E-mail: gionnimarchetti@gmail.com; Hodgson, Matthew, E-mail: matthew.hodgson@york.ac.uk; D' Amico, Irene, E-mail: irene.damico@york.ac.uk [Department of Physics, University of York, York, Heslington YO10 5DD (United Kingdom)

    2014-10-28

    We study the spin decoherence in n-type bulk GaAs for moderate electronic densities at room temperature using the Ensemble Monte Carlo method. We demonstrate that a technique called “third-body rejection method” devised by B. K. Ridley, J. Phys. C: Solid State Phys. 10, 1589 (1977) can be successfully adapted to Ensemble Monte Carlo method and used to tackle the problem of the electron-electron contribution to spin decoherence in the parameter region under study, where the electron-electron interaction can be reasonably described by a Yukawa potential. This scattering technique is employed in a doping region where one can expect that multiple collisions may play a role in carrier dynamics. By this technique, we are able to calculate spin relaxation times which are in very good agreement with the experimental results found by Oertel et al., Appl. Phys. Lett. 93, 13 (2008). Through this method, we show that the electron-electron scattering is overestimated in Born approximation, in agreement with previous results obtained by C. A. Kukkonen and H. Smith, Phys. Rev. B 8, 4601 (1973).

  19. Electron-plasmon and electron-electron interactions at a single atom contact.

    Science.gov (United States)

    Schull, Guillaume; Néel, Nicolas; Johansson, Peter; Berndt, Richard

    2009-02-06

    The transition from tunneling to contact is investigated by detecting light emitted from Au(111) in a scanning tunneling microscope. Optical spectra reflect single and multielectron processes and their distinct evolutions as a single-atom contact is formed. The experimental data are analyzed in terms of plasmon excitation and hot-hole processes.

  20. Does the Higgs mechanism favour electron-electron bound states in Maxwell-Chern-Simons $QED_{3}$?

    CERN Document Server

    Belich, H; Helayël-Neto, José A

    2000-01-01

    The low-energy electron-electron scattering potential is derived and discussed for the Maxwell-Chern-Simons model coupled to QED_3 with spontaneous symmetry breaking. One shows that the Higgs mechanism might favour electron-electron bound states.

  1. Einstein Ring in Distant Universe

    Science.gov (United States)

    2005-06-01

    Using ESO's Very Large Telescope, Rémi Cabanac and his European colleagues have discovered an amazing cosmic mirage, known to scientists as an Einstein Ring. This cosmic mirage, dubbed FOR J0332-3557, is seen towards the southern constellation Fornax (the Furnace), and is remarkable on at least two counts. First, it is a bright, almost complete Einstein ring. Second, it is the farthest ever found. ESO PR Photo 20a/05 ESO PR Photo 20a/05 Deep Image of a Region in Fornax (FORS/VLT) [Preview - JPEG: 400 x 434 pix - 60k] [Normal - JPEG: 800 x 867 pix - 276k] [Full Res - JPEG: 1859 x 2015 pix - 3.8M] ESO PR Photo 20b/05 ESO PR Photo 20b/05 Zoom-in on the Newly Found Einstein Ring (FORS/VLT) [Preview - JPEG: 400 x 575 pix - 168k] [Normal - JPEG: 630 x 906 pix - 880k] Caption: ESO PR Photo 20a/05 is a composite image taken in two bands (B and R) with VLT/FORS1 of a small portion of the sky (field-of-view 7x7' or 1/15th of the area of the full moon). The faintest object seen in the image has a magnitude 26, that is, it is 100 million times fainter than what can be observed with the unaided eye. The bright elliptical galaxy on the lower-left quadrant is a dwarf galaxy part of a large nearby cluster in the Fornax constellation. As for all deep images of the sky, this field shows a variety of objects, the brightest ponctual sources being stars from our Galaxy. By far the field is dominated by thousands of faint background galaxies the colours of which are related to the age of their dominant stellar population, their dust content and their distance. The newly found Einstein ring is visible in the top right part of the image. ESO PR Photo 20b/05 zooms-in on the position of the newly found cosmic mirage. ESO PR Photo 20c/05 ESO PR Photo 20c/05 Einstein Ring in Distant Universe (FORS/VLT) [Preview - JPEG: 400 x 584 pix - 104k] [Normal - JPEG: 800 x 1168 pix - 292k] [Full Res - JPEG: 1502 x 2192 pix - 684k] Caption of ESO PR Photo 20c/05: The left image is magnified and centred

  2. Observation of autoionization in O 2 by an electron-electron coincidence method

    Science.gov (United States)

    Doering, J. P.; Yang, J.; Cooper, J. W.

    1995-01-01

    A strong transition to an autoionizing stata has been observed in O 2 at 16.83 ± 0.11 eV by means of a new electron-electron conincidence method. The method uses the fact that electrons arising from autoionizing states appear at a constant energy loss corresponding to the excitation energy of the autoionizing state rather than at a constant ionization potential as do electrons produced by direct ionization. Comparison of the present data with previous photoionization studies suggests that the autoionizing O 2 state is the same state deduced to be responsible for abnormal vibrational intensities in the O 2+X 2Πg ground state when 16.85 eV Ne(I) photons are used. These electron-electron coincidence experiments provide a direct new method for the study of autoionization produced by electron impact.

  3. Pure electron-electron dephasing in percolative aluminum ultrathin film grown by molecular beam epitaxy.

    Science.gov (United States)

    Lin, Shih-Wei; Wu, Yue-Han; Chang, Li; Liang, Chi-Te; Lin, Sheng-Di

    2015-01-01

    We have successfully grown ultrathin continuous aluminum film by molecular beam epitaxy. This percolative aluminum film is single crystalline and strain free as characterized by transmission electron microscopy and atomic force microscopy. The weak anti-localization effect is observed in the temperature range of 1.4 to 10 K with this sample, and it reveals that, for the first time, the dephasing is purely caused by electron-electron inelastic scattering in aluminum.

  4. Effects of interactions in two dimensions

    Energy Technology Data Exchange (ETDEWEB)

    Shashkin, A A; Kapustin, A A; Deviatov, E V; Dolgopolov, V T [Institute of Solid State Physics, Chernogolovka, Moscow District 142432 (Russian Federation); Kvon, Z D [Institute of Semiconductor Physics, Novosibirsk 630090 (Russian Federation); Kravchenko, S V [Physics Department, Northeastern University, Boston, Massachusetts 02115 (United States)], E-mail: s.kravchenko@neu.edu

    2009-05-29

    Strong electron-electron interactions in dilute two-dimensional electron systems in silicon lead to Pauli spin susceptibility growing critically at low electron densities. This effect originates from renormalization of the effective mass rather than the g-factor. The relative mass enhancement is system and disorder independent, which suggests that it is determined by electron-electron interactions only.

  5. Distant Fathers: Disjointed World of George Eliot

    Directory of Open Access Journals (Sweden)

    Tahira Jabeen

    2014-01-01

    Full Text Available The article discusses distant fathers in the novels of George Eliot within the context of the nineteenth century. In the nineteenth-century Britain, the father’s role is best defined by Nelson, “authority, guidance and financial support”. (Natalie 2011, p.155 The article is devoted to explore the distant or absent fathers, which means no guidance, protection, and financial support to the children. The absence might be the consequences of many aspects relating to fathers. The father could be absent either physically or emotionally. The article argues that Eliot seeks and yearns for a perfect fatherhood by showing some shortcomings of the father and its effects on the lives of their children. Keywords: George Eliot, distant fathers, nineteenth century

  6. Reaction enhancement of initially distant scalars by Lagrangian coherent structures

    Energy Technology Data Exchange (ETDEWEB)

    Pratt, Kenneth R., E-mail: kenneth.pratt@colorado.edu; Crimaldi, John P., E-mail: john.crimaldi@colorado.edu [Department of Civil, Environmental and Architectural Engineering, University of Colorado, Boulder, Colorado 80309-0428 (United States); Meiss, James D., E-mail: james.meiss@colorado.edu [Department of Applied Mathematics, University of Colorado, Boulder, Colorado 80309-0526 (United States)

    2015-03-15

    Turbulent fluid flows have long been recognized as a superior means of diluting initial concentrations of scalars due to rapid stirring. Conversely, experiments have shown that the structures responsible for this rapid dilution can also aggregate initially distant reactive scalars and thereby greatly enhance reaction rates. Indeed, chaotic flows not only enhance dilution by shearing and stretching but also organize initially distant scalars along transiently attracting regions in the flow. To show the robustness of this phenomenon, a hierarchical set of three numerical flows is used: the periodic wake downstream of a stationary cylinder, a chaotic double gyre flow, and a chaotic, aperiodic flow consisting of interacting Taylor vortices. We demonstrate that Lagrangian coherent structures (LCS), as identified by ridges in finite time Lyapunov exponents, are directly responsible for this coalescence of reactive scalar filaments. When highly concentrated filaments coalesce, reaction rates can be orders of magnitude greater than would be predicted in a well-mixed system. This is further supported by an idealized, analytical model that was developed to quantify the competing effects of scalar dilution and coalescence. Chaotic flows, known for their ability to efficiently dilute scalars, therefore have the competing effect of organizing initially distant scalars along the LCS at timescales shorter than that required for dilution, resulting in reaction enhancement.

  7. Pattern of distant recurrence according to the molecular subtypes in Korean women with breast cancer

    Directory of Open Access Journals (Sweden)

    Park Hyung Seok

    2012-01-01

    Full Text Available Abstract Background Distant recurrence is one of the most important risk factors in overall survival, and distant recurrence is related to a complex biologic interaction of seed and soil factors. The aim of the study was to investigate the association between the molecular subtypes and patterns of distant recurrence in patients with breast cancer. Methods In an investigation of 313 women with breast cancer who underwent surgery from 1994 and 2000, the expressions of estrogen and progestrone receptor (ER/PR, and human epithelial receptor-2 (HER2 were evaluated. The subtypes were defined as luminal-A, luminal-HER2, HER2-enriched, and triple negative breast cancer (TNBC according to ER, PR, and HER2 status. Results Bone was the most common site of distant recurrence. The incidence of first distant recurrence site was significantly different among the subtypes. Brain metastasis was more frequent in the luminal-HER2 and TNBC subtypes. In subgroup analysis, overall survival in patients with distant recurrence after 24 months after surgery was significantly different among the subtypes. Conclusions Organ-specific metastasis may depend on the molecular subtype of breast cancer. Tailored strategies against distant metastasis concerning the molecular subtypes in breast cancer may be considered.

  8. Pulsed electron-electron double resonance (PELDOR) as EPR spectroscopy in nanometre range

    Energy Technology Data Exchange (ETDEWEB)

    Tsvetkov, Yu D; Milov, A D; Maryasov, A G [Institute of Chemical Kinetics and Combustion, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2008-06-30

    The results of development of pulsed electron-electron double resonance (PELDOR) method and its applications in structural studies are generalised and described systematically. The foundations of the theory of the method are outlined, some methodological features and applications are considered, in particular, determination of the distances between spin labels in the nanometre range for iminoxyl biradicals, spin-labelled biomacromolecules, radical ion pairs and peptide-membrane complexes. The attention is focussed on radical systems that form upon self-assembly of nanosized complexes (in particular, peptide complexes), spatial effects, and radical pairs in photolysis and photosynthesis. The position of PELDOR among other structural EPR techniques is analysed.

  9. Experimental investigation of collisionless electron-electron microinstabilities. Final technical report for the period August 1, 1997-October 31, 2000

    Energy Technology Data Exchange (ETDEWEB)

    Scime, Earl E. [West Virginia Univ., Morgantown, WV (United States)

    2000-12-11

    This is the final report for the Office of Fusion Energy sponsored project entitled, "Experimental Investigation of Collisionless Electron-Electron Microinstabilities." The report summarizes the scientific and human resource development accomplishments supported through this project.

  10. Did Egret Detect Distant Supernova Remnants?

    CERN Document Server

    Torres, D F; Dame, T M; Combi, J A; Butt, Y M; Torres, Diego F.; Romero, Gustavo E.; Dame, Thomas M.; Combi, Jorge A.; Butt, Yousaf M.

    2004-01-01

    It might be thought that supernova remnants (SNRs) more distant than a few kiloparsec from Earth could not have been detected by the EGRET experiment. This work analyzes the observational status of this statement in the light of new CO studies of SNRs.

  11. Black-hole masses of distant quasars

    DEFF Research Database (Denmark)

    Vestergaard, Marianne

    2011-01-01

    A brief overview of the methods commonly used to determine or estimate the black hole mass in quiescent or active galaxies is presented and it is argued that the use of mass-scaling relations is both a reliable and the preferred method to apply to large samples of distant quasars. The method uses...

  12. EISily looking for distant galaxy clusters

    CERN Document Server

    Lobo, C; Iovino, A; Guzzo, L; Chincarini, G L; Lobo, Catarina; Lazzati, Davide; Iovino, Angela; Guzzo, Luigi; Chincarini, Guido

    1998-01-01

    We present a new algorithm to search for distant clusters of galaxies on catalogues deriving from imaging data, as those of the ESO Imaging Survey. We discuss the advantages of our technique relative to the ones developed before and present preliminary results of its application to the I--band data of the survey's patch A.

  13. distant metastases from nasopharyngeal carcinoma at kenyatta ...

    African Journals Online (AJOL)

    2001-12-12

    Dec 12, 2001 ... The preponderance of early primary disease in patients with distant metastasis need ... Hospital (KNH) cancer registry as depicted in Table 1. The frequency .... 12.1. Pelvis. 9. 9.1. Femur. 7. 7.1. Lungs. 5. 5.1. Thoracic vertebrae. 4. 4.1. Sternum ... health units nearest to their homes for terminal management.

  14. An Effective Entanglement among Three Fibre-Connected Distant Atoms

    Institute of Scientific and Technical Information of China (English)

    GUO Yan-Qing; CHEN Jing; SONG He-Shan

    2006-01-01

    @@ Under the enlightenment of the scheme of Mancini and Bose [Phys. Rev. A 70 (2004)022307), we discuss two-atom entanglement in a fibre-connected triple-distant-atom system. Under adiabatic approximation, we obtain an effective Hamiltonian in form of the triple-body Ising-model interaction. The existence of a third atom is found to damage the other two-atom entanglement. The nearest-neighbouring two atoms that share a larger Ising strength are more strongly entangled.

  15. Phospholipid bilayer relaxation dynamics as revealed by the pulsed electron-electron double resonance of spin labels

    Science.gov (United States)

    Syryamina, V. N.; Dzuba, S. A.

    2012-10-01

    Electron paramagnetic resonance (EPR) spectroscopy in the form of pulsed electron-electron double resonance (ELDOR) was applied to 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) phospholipid bilayers containing lipids that were spin-labeled at different carbon positions along the lipid acyl chain. Pulsed ELDOR detects motionally induced spin flips of nitrogen nuclei in the nitroxide spin labels, which manifests itself as magnetization transfer (MT) in the nitroxide EPR spectrum. The MT effect was observed over a wide temperature range (100-225 K) on a microsecond time scale. In line with a previous study on molecular glasses [N. P. Isaev and S. A. Dzuba, J. Chem. Phys. 135, 094508 (2011), 10.1063/1.3633241], the motions that induce MT effect were suggested to have the same nature as those in dielectric secondary (β) Johari-Goldstein fast relaxation. The results were compared with literature dielectric relaxation data for POPC bilayers, revealing some common features. Molecular motions resulting in MT are faster for deeper spin labels in the membrane interior. The addition of cholesterol to the bilayer suppresses the lipid motions near the steroid nucleus and accelerates the lipid motions beyond the steroid nucleus, in the bilayer interior. This finding was attributed to the lipid acyl chains being more ordered near the steroid nucleus and less ordered in the bilayer interior. The motions are absent in dry lipids, indicating that the motions are determined by intermolecular interactions in the bilayer.

  16. Development of Distant Learning Laboratory and Creation of Educational Materials

    Science.gov (United States)

    Considine, Michelle

    1995-01-01

    The Office of Education's fundamental goal is to disseminate information, mostly that which relates to science and technology. In this attempt, as I have observed, the office has many programs bringing both students and teachers to NASA Langley to expose them to the facilities and to teach them some about the scientific theory and about available modern technology. As a way of expanding the audience that can be reached, as the expense of bringing people in is limiting, Marchelle Canright has proposed establishing a center dedicated to researching and producing distant learning videos. Although distant learning through telecommunications is not a new concept, as many universities, colleges, and precollege level schools offer televised courses, the research in this field has been limited. Many of the standing distant learning broadcasts are simply recordings of teachers in classrooms giving lectures to their own students; they are not aimed at the television audience. In some cases the videos are produced without a Live-lecture atmosphere, but are still only classroom lectures. In either case, however, the full range of capabilities of video production are not being fully utilized. Methods for best relaying educational material have not been explored. Possibilities for including computerized images and video clips for the purpose of showing diagrams and processes, as well as examples in fitting cases, may add considerably to the educational value of these videos. Also, through Internet and satellite links, it is possible for remote students to interact with the teachers during televised sessions. These possibilities might, also, add to the effectiveness of distant learning programs. Ms. Canright's proposed center will be dedicated to researching these possibilities and eventually spreading the results to distant learning program managers. This is the project I was involved in over the summer. As implied, the center is still at the foundation stages. Ms. Canright has

  17. Distant hybridization leads to different ploidy fishes

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Distant hybridization makes it possible to transfer the genome of one species to another, which results in changes in phenotypes and genotypes of the progenies. This study shows that distant hybridization or the combination of this method with gynogenesis or androgenesis lead to different ploidy fishes with genetic variation, including fertile tetraploid hybrids, sterile triploid hybrids, fertile diploid hybrids, fertile diploid gynogenetic fish, and their derived progenies. The formations of the different ploidy fishes depend on the genetic relationship between the parents. In this study, several types of distant hybridization, including red crucian carp (Carassius auratus red var.) (2n=100, abbreviated as RCC) (♀)×common carp (Cyprinus carpio L.) (2n=100, abbreviated as CC) (♂), and RCC (2n=100) (♀)×blunt snout bream (Megalobrama amblycephala) (2n=48, abbreviated as BSB) (♂) are described. In the distant hybridization of RCC (♀)×CC (♂), bisexual fertile F3–F18 allotetraploid hybrids (4n=200, abbreviated as 4nAT) were formed. The diploid hybrid eggs and diploid sperm generated by the females and males of 4nAT developed into diploid gynogenetic hybrids and diploid androgenetic hybrids, respectively, by gynogenesis and androgenesis, without treatment for doubling the chromosome. Improved tetraploid hybrids and improved diploid fishes with genetic variation were derived from the gynogenetic hybrid line. The improved diploid fishes included the high-body RCC and high-body goldfish. The formation of the tetraploid hybrids was related to the occurrence of unreduced gametes generated from the diploid hybrids, which involved in premeiotic endoreduplication, endomitosis, or fusion of germ cells. The sterile triploid hybrids (3n=150) were produced on a large scale by crossing the males of tetraploid hybrids with females of diploid fish (2n=100). In another distant hybridization of RCC (♀)×BSB (♂), different ploidy fishes were obtained, including

  18. Distant hybridization leads to different ploidy fishes.

    Science.gov (United States)

    Liu, ShaoJun

    2010-04-01

    Distant hybridization makes it possible to transfer the genome of one species to another, which results in changes in phenotypes and genotypes of the progenies. This study shows that distant hybridization or the combination of this method with gynogenesis or androgenesis lead to different ploidy fishes with genetic variation, including fertile tetraploid hybrids, sterile triploid hybrids, fertile diploid hybrids, fertile diploid gynogenetic fish, and their derived progenies. The formations of the different ploidy fishes depend on the genetic relationship between the parents. In this study, several types of distant hybridization, including red crucian carp (Carassius auratus red var.) (2n=100, abbreviated as RCC) (female) x common carp (Cyprinus carpio L.) (2n=100, abbreviated as CC) (male), and RCC (2n=100) (female) x blunt snout bream (Megalobrama amblycephala) (2n=48, abbreviated as BSB) (male) are described. In the distant hybridization of RCC (female) x CC (male), bisexual fertile F(3)-F(18) allotetraploid hybrids (4n=200, abbreviated as 4nAT) were formed. The diploid hybrid eggs and diploid sperm generated by the females and males of 4nAT developed into diploid gynogenetic hybrids and diploid androgenetic hybrids, respectively, by gynogenesis and androgenesis, without treatment for doubling the chromosome. Improved tetraploid hybrids and improved diploid fishes with genetic variation were derived from the gynogenetic hybrid line. The improved diploid fishes included the high-body RCC and high-body goldfish. The formation of the tetraploid hybrids was related to the occurrence of unreduced gametes generated from the diploid hybrids, which involved in premeiotic endoreduplication, endomitosis, or fusion of germ cells. The sterile triploid hybrids (3n=150) were produced on a large scale by crossing the males of tetraploid hybrids with females of diploid fish (2n=100). In another distant hybridization of RCC (female) x BSB (male), different ploidy fishes were

  19. Bias Modeling for Distantly Supervised Relation Extraction

    Directory of Open Access Journals (Sweden)

    Yang Xiang

    2015-01-01

    Full Text Available Distant supervision (DS automatically annotates free text with relation mentions from existing knowledge bases (KBs, providing a way to alleviate the problem of insufficient training data for relation extraction in natural language processing (NLP. However, the heuristic annotation process does not guarantee the correctness of the generated labels, promoting a hot research issue on how to efficiently make use of the noisy training data. In this paper, we model two types of biases to reduce noise: (1 bias-dist to model the relative distance between points (instances and classes (relation centers; (2 bias-reward to model the possibility of each heuristically generated label being incorrect. Based on the biases, we propose three noise tolerant models: MIML-dist, MIML-dist-classify, and MIML-reward, building on top of a state-of-the-art distantly supervised learning algorithm. Experimental evaluations compared with three landmark methods on the KBP dataset validate the effectiveness of the proposed methods.

  20. Bias Modeling for Distantly Supervised Relation Extraction

    OpenAIRE

    Yang Xiang; Yaoyun Zhang; Xiaolong Wang; Yang Qin; Wenying Han

    2015-01-01

    Distant supervision (DS) automatically annotates free text with relation mentions from existing knowledge bases (KBs), providing a way to alleviate the problem of insufficient training data for relation extraction in natural language processing (NLP). However, the heuristic annotation process does not guarantee the correctness of the generated labels, promoting a hot research issue on how to efficiently make use of the noisy training data. In this paper, we model two types of biases to reduce...

  1. Gram-negative bacterial infection in thigh abscess can migrate to distant burn depending on burn depth

    National Research Council Canada - National Science Library

    Hamrahi, Victoria; Hamblin, Michael R; Jung, Walter; Benjamin, John B; Paul, Kasie W; Fischman, Alan J; Tompkins, Ronald G; Carter, Edward A

    2012-01-01

    Sepsis remains the major cause of death in patients with major burn injuries. In the present investigation we evaluated the interaction between burn injuries of varying severity and preexisting distant infection...

  2. Gram-Negative Bacterial Infection in Thigh Abscess Can Migrate to Distant Burn Depending on Burn Depth

    National Research Council Canada - National Science Library

    Hamrahi, Victoria; Hamblin, Michael R; Jung, Walter; Benjamin, John B; Paul, Kasie W; Fischman, Alan J; Tompkins, Ronald G; Carter, Edward A

    2012-01-01

    Sepsis remains the major cause of death in patients with major burn injuries. In the present investigation we evaluated the interaction between burn injuries of varying severity and preexisting distant infection...

  3. The effect of electron-electron correlation on the attoclock experiment

    CERN Document Server

    Emmanouilidou, A; Hofmann, C; Keller, U; Landsman, A S

    2015-01-01

    We investigate multi-electron effects in strong-field ionization of Helium using a semi-classical model that, unlike other commonly used theoretical approaches, takes into account electron-electron correlation. Our approach has an additional advantage of allowing to selectively switch off different contributions from the parent ion (such as the remaining electron or the nuclear charge) and thereby investigate in detail how the final electron angle in the attoclock experiment is influenced by these contributions. We find that the bound electron exerts a significant effect on the final electron momenta distribution that can, however, be accounted for by an appropriately selected mean field. Our results show excellent agreement with other widely used theoretical models done within a single active electron approximation.

  4. Percolated Superconductivity and Electron-Electron Exchange Mechanism in Ba-La-Cu-O

    Science.gov (United States)

    Tao, Ruibao

    It is found that the oxygen vacancies at the Cu-O basal plane of oxide (La1-xBax)2CuO4-y (Balacuo) will break the bonds of Cu-O-Cu to make the hopping between those coppers disappear so that the electrical conduction in the Cu-O basal plane would become a bond percolation system consisting of an infinite cluster carrying the current with a great number of finite clusters hanging around. It is favorable to create some mechanism of electron-electron exchange so that the transition temperature Tc of superconductivity could be increased significantly. The comparison with Y1Ba2Cu3O9-y is also discussed briefly.

  5. Electron-electron double resonance (ELDOR) with a loop-gap resonator

    Science.gov (United States)

    Hyde, James S.; Yin, Jun-Jie; Froncisz, W.; Feix, Jimmy B.

    Electron-electron double-resonance (ELDOR) experiments on nitroxide-radical-spin-labeled liposomes have been performed using a loop-gap resonator. The signal-to-noise ratio expressed on a molarity basis is 20-fold over the best that has been achieved using a bimodal cavity. This improvement permits ELDOR experiments on spin-labeled plasma membranes of intact cells, as illustrated by a prototype experiment on red blood cells labeled with stearic acid spin label. Moreover, 20 times greater pumping energy density at the sample is achievable for a given incident pump power, permitting ELDOR experiments on less readily saturated systems. Pump and observing frequencies are introduced directly into the loop-gap resonator, which has a relatively low Q, and the pump electron paramagnetic resonance signal is isolated from the receiver using a high Q trap microwave filter.

  6. The Cosmic Dance of Distant Galaxies

    Science.gov (United States)

    2006-03-01

    GIRAFFE at VLT reveals the turbulent life of distant galaxies Studying several tens of distant galaxies, an international team of astronomers found that galaxies had the same amount of dark matter relative to stars 6 billion years ago as they have now. If confirmed, this suggests a much closer interplay between dark and normal matter than previously believed. The scientists also found that as many as 4 out of 10 galaxies are out of balance. These results shed a new light on how galaxies form and evolve since the Universe was only half its current age. ESO PR Photo 10a/06 ESO PR Photo 10a/06 Collision Between Galaxies (Artist's Impression) "This may imply that collisions and merging are important in the formation and evolution of galaxies", said François Hammer, Paris Observatory, France, and one of the leaders of the team [1]. The scientists were interested in finding out how galaxies that are far away - thus seen as they were when the Universe was younger - evolved into the ones nearby. In particular, they wanted to study the importance of dark matter in galaxies. "Dark matter, which composes about 25% of the Universe, is a simple word to describe something we really don't understand," said Hector Flores, co-leader. "From looking at how galaxies rotate, we know that dark matter must be present, as otherwise these gigantic structures would just dissolve." In nearby galaxies, and in our own Milky Way for that matter, astronomers have found that there exists a relation between the amount of dark matter and ordinary stars: for every kilogram of material within a star there is roughly 30 kilograms of dark matter. But does this relation between dark and ordinary matter still hold in the Universe's past? ESO PR Photo 10b/06 ESO PR Photo 10b/06 Mapping Distant Galaxies (FLAMES-GIRAFFE/VLT) This required measuring the velocity in different parts of distant galaxies, a rather tricky experiment: previous measurements were indeed unable to probe these galaxies in sufficient

  7. Video-mediated communication to support distant family connectedness.

    Science.gov (United States)

    Furukawa, Ryoko; Driessnack, Martha

    2013-02-01

    It can be difficult to maintain family connections with geographically distant members. However, advances in computer-human interaction (CHI) systems, including video-mediated communication (VMC) are emerging. While VMC does not completely substitute for physical face-to-face communication, it appears to provide a sense of virtual copresence through the addition of visual and contextual cues to verbal communication between family members. The purpose of this study was to explore current patterns of VMC use, experiences, and family functioning among self-identified VMC users separated geographically from their families. A total of 341 participants (ages 18 to above 70) completed an online survey and Family APGAR. Ninty-six percent of the participants reported that VMC was the most common communication method used and 60% used VMC at least once/week. The most common reason cited for using VMC over other methods of communication was the addition of visual cues. A significant difference between the Family APGAR scores and the number of positive comments about VMC experience was also found. This exploratory study provides insight into the acceptance of VMC and its usefulness in maintaining connections with distant family members.

  8. New views of the distant stellar halo

    CERN Document Server

    Sanderson, Robyn E; Johnston, Kathryn V; Bochanski, John J

    2016-01-01

    Currently only a small number of Milky Way (MW) stars are known to exist beyond 100 kpc from the Galactic center. Though the distribution of these stars in the outer halo is believed to be sparse, they can provide evidence of more recent accretion events than in the inner halo and help map out the MW's dark matter halo to its virial radius. We have re-examined the outermost regions of 11 existing stellar halo models with two synthetic surveys: one mimicking present-day searches for distant M giants and another mimicking RR Lyrae (RRLe) projections for LSST. Our models suggest that color and proper motion cuts currently used to select M giant candidates for follow-up successfully remove nearly all halo dwarf self-contamination and are useful for focusing observations on distant M giants, of which there are thousands to tens of thousands beyond 100 kpc in our models. We likewise expect that LSST will identify comparable numbers of RRLe at these distances. We demonstrate that several observable properties of bot...

  9. Distant Site Effects of Ingested Prebiotics

    Directory of Open Access Journals (Sweden)

    Stephanie Collins

    2016-08-01

    Full Text Available The gut microbiome is being more widely recognized for its association with positive health outcomes, including those distant to the gastrointestinal system. This has given the ability to maintain and restore microbial homeostasis a new significance. Prebiotic compounds are appealing for this purpose as they are generally food-grade substances only degraded by microbes, such as bifidobacteria and lactobacilli, from which beneficial short-chain fatty acids are produced. Saccharides such as inulin and other fructo-oligosaccharides, galactooligosaccharides, and polydextrose have been widely used to improve gastrointestinal outcomes, but they appear to also influence distant sites. This review examined the effects of prebiotics on bone strength, neural and cognitive processes, immune functioning, skin, and serum lipid profile. The mode of action is in part affected by intestinal permeability and by fermentation products reaching target cells. As the types of prebiotics available diversify, so too will our understanding of the range of microbes able to degrade them, and the extent to which body sites can be impacted by their consumption.

  10. Distant Site Effects of Ingested Prebiotics.

    Science.gov (United States)

    Collins, Stephanie; Reid, Gregor

    2016-08-26

    The gut microbiome is being more widely recognized for its association with positive health outcomes, including those distant to the gastrointestinal system. This has given the ability to maintain and restore microbial homeostasis a new significance. Prebiotic compounds are appealing for this purpose as they are generally food-grade substances only degraded by microbes, such as bifidobacteria and lactobacilli, from which beneficial short-chain fatty acids are produced. Saccharides such as inulin and other fructo-oligosaccharides, galactooligosaccharides, and polydextrose have been widely used to improve gastrointestinal outcomes, but they appear to also influence distant sites. This review examined the effects of prebiotics on bone strength, neural and cognitive processes, immune functioning, skin, and serum lipid profile. The mode of action is in part affected by intestinal permeability and by fermentation products reaching target cells. As the types of prebiotics available diversify, so too will our understanding of the range of microbes able to degrade them, and the extent to which body sites can be impacted by their consumption.

  11. Distant Site Effects of Ingested Prebiotics

    Science.gov (United States)

    Collins, Stephanie; Reid, Gregor

    2016-01-01

    The gut microbiome is being more widely recognized for its association with positive health outcomes, including those distant to the gastrointestinal system. This has given the ability to maintain and restore microbial homeostasis a new significance. Prebiotic compounds are appealing for this purpose as they are generally food-grade substances only degraded by microbes, such as bifidobacteria and lactobacilli, from which beneficial short-chain fatty acids are produced. Saccharides such as inulin and other fructo-oligosaccharides, galactooligosaccharides, and polydextrose have been widely used to improve gastrointestinal outcomes, but they appear to also influence distant sites. This review examined the effects of prebiotics on bone strength, neural and cognitive processes, immune functioning, skin, and serum lipid profile. The mode of action is in part affected by intestinal permeability and by fermentation products reaching target cells. As the types of prebiotics available diversify, so too will our understanding of the range of microbes able to degrade them, and the extent to which body sites can be impacted by their consumption. PMID:27571098

  12. Sistema interactivo como objeto virtual de aprendizaje aplicado a las técnicas de comunicación en comunidades lejanas de la República Democrática del Congo Interactive system as virtual learning object applied to the skils of communication in distant communities of the Democratic Republic of Congo

    Directory of Open Access Journals (Sweden)

    Gilmar Rolando Anaguano Jiménez

    2008-07-01

    Full Text Available El presente trabajo contiene la descripción del producto final del proyecto 'Sistema interactivo como objeto virtual de aprendizaje aplicado a las técnicas de comunicación en comunidades lejanas de la República Democrática del Congo.', diseñado a la medida y basado en los requerimientos específicos del usuario final (Misioneros de la Consolata radicados en ese país. Este producto consiste en un prototipo de software orientado por los procesos del ciclo de vida del mismo (Planificación, análisis de requerimientos, diseño, desarrollo e implementación, realizado para aplicar las estrategias postuladas por la teoría de aprendizaje mixto (Blended Learning; las cuales se centran en la combinación de sesiones presenciales con actividades virtuales.This article is the result of the research project: 'Interactive System as a Virtual Learning Object Applied Communication Techniques in Distant Communities of the Democratic Republic of the Congo,' customized and based on the final user's specific requirements (Missionaries of the Consolata living in this country. The system is a prototype of software oriented by the processes of the cycle of life (planning, analysis of requirements, design, development and implementation, performed to apply strategies established by the Theory of Blended Learning, which uses face-to-face classrooms, live e-learning, and self-paced learning.

  13. ALMA Examines a Distant Quasar Host

    Science.gov (United States)

    Kohler, Susanna

    2017-04-01

    The dust continuum (top) and the [CII] emission (bottom) maps for the region around J1120+0641. [Adapted from Venemans et al. 2017]A team of scientists has used the Atacama Large Millimeter/submillimeter Array (ALMA) to explore the host galaxy of the most distant quasar known. Their observations may help us to build a picture of how the first supermassive black holes in the universe formed and evolved.Faraway Monsters and Their GalaxiesWe know that quasars the incredibly luminous and active centers of some distant galaxies are powered by accreting, supermassive black holes. These monstrous powerhouses have been detected out to redshifts of z 7, when the universe was younger than a billion years old.Though weve observed over a hundred quasars at high redshift, we still dont understand how these early supermassive black holes formed, or whether the black holes and the galaxies that host them co-evolved. In order to answer questions like these, however, we first need to gather information about the properties and behavior of various supermassive black holes and their host galaxies.A team of scientists led by Bram Venemans (Max-Planck Institute for Astronomy, Germany) recently used the unprecedented sensitivity and angular resolution of ALMA as well as the Very Large Array and the IRAM Plateau de Bure Interferometer to examine the most distant quasar currently known, J1120+0641, located at a redshift of z = 7.1.A High-Resolution LookThe teams observations of the dust and gas emission from the quasars host galaxy revealed a number of intriguing things:The red and blue sides of the [CII] emission line are shown here as contours, demonstrating that theres no ordered rotational motion of the gas on kpc scales. [Adapted from Venemans et al. 2017]The majority of the galaxys emission is very compact. Around 80% of the observed flux came from a region of only 11.5 kpc in diameter.Despite the fact that the 2.4-billion-solar-mass black hole at the galaxys center is accreting at

  14. Mechanism of spin diffusion in electron spin resonance spectra of trapped electrons in aqueous glasses. Electron--Electron double resonance studies. [. gamma. -rays

    Energy Technology Data Exchange (ETDEWEB)

    Lin, D.P.; Kevan, L.

    1977-05-19

    Electron--electron double resonance (ELDOR) has been used to test the validity of the noninteracting spin packet model for inhomogeneously broadened ESR lines. For trapped electrons in 10M NaOD/D/sub 2/O glassy ice the saturation of field-swept ELDOR spectra fits the above mentioned model in contrast to earlier work on trapped electrons in protiated matrices. In the protiated matrix spin diffusion produces significant interaction between the spin packets. The difference between the protiated and deuterated matrices suggests that nuclear relaxation is the mechanism for spin diffusion. The deuterated matrices show no structure in frequency-swept ELDOR spectra due to deuteron spin--flip transitions whereas structure due to proton spin--flips is seen in protiated matrices.

  15. Entanglement dynamics of two distant atoms in two detuning cavities

    Institute of Scientific and Technical Information of China (English)

    Ji Xin; L(u) Tian-Quan; Zhang Shou

    2010-01-01

    We investigate the entanglement dynamics via the concurrence of two distant atoms interacting off-resonantly with two cavity fields in Fock states, respectively. We find that the evolution of entanglement has sudden death and sudden birth phenomena, that with the increase of photon numbers in the two cavities, the alternate frequency of sudden death and sudden birth turns fast, and that the amplitude of concurrence oscillates regularly with oscillation frequency becoming slow when the cavity fields have the same photon numbers. While, the maximum of concurrence declines and the amplitude of concurrence oscillates irregularly when the two cavity fields have different photon numbers. In addition, we find the length of death time is dependent on the initial entanglement.

  16. Cosmic Lens Reveals Distant Galactic Violence

    Science.gov (United States)

    2008-10-01

    By cleverly unraveling the workings of a natural cosmic lens, astronomers have gained a rare glimpse of the violent assembly of a young galaxy in the early Universe. Their new picture suggests that the galaxy has collided with another, feeding a supermassive black hole and triggering a tremendous burst of star formation. Gravitational Lens Diagram Imaging a Distant Galaxy Using a Gravitational Lens CREDIT: Bill Saxton, NRAO/AUI/NSF Click on image for details and more graphics. The astronomers used the National Science Foundation's Very Large Array (VLA) radio telescope to look at a galaxy more than 12 billion light-years from Earth, seen as it was when the Universe was only about 15 percent of its current age. Between this galaxy and Earth lies another distant galaxy, so perfectly aligned along the line of sight that its gravity bends the light and radio waves from the farther object into a circle, or "Einstein Ring." This gravitational lens made it possible for the scientists to learn details of the young, distant galaxy that would have been unobtainable otherwise. "Nature provided us with a magnifying glass to peer into the workings of a nascent galaxy, providing an exciting look at the violent, messy process of building galaxies in the early history of the Universe," said Dominik Riechers, who led this project at the Max Planck Institute for Astronomy in Germany and now is a Hubble Fellow at the California Institute of Technology (Caltech). The new picture of the distant galaxy, dubbed PSS J2322+1944, shows a massive reservoir of gas, 16,000 light-years in diameter, that contains the raw material for building new stars. A supermassive black hole is voraciously eating material, and new stars are being born at the rate of nearly 700 Suns per year. By comparison, our Milky Way Galaxy produces the equivalent of about 3-4 Suns per year. The black hole appears to be near the edge, rather than at the center, of the giant gas reservoir, indicating, the astronomers say

  17. On the importance of electron-electron scattering for hot-carrier degradation

    Science.gov (United States)

    Tyaginov, Stanislav; Bina, Markus; Franco, Jacopo; Wimmer, Yannick; Kaczer, Ben; Grasser, Tibor

    2015-04-01

    Using our physics based model for hot-carrier degradation (HCD) we analyze the importance of the effect of electron-electron scattering (EES) on HCD in transistors with different channel lengths. The model is based on a thorough treatment of carrier transport and is implemented into the deterministic Boltzmann transport equation solver ViennaSHE. Two competing mechanism of Si-H bond-breakage are captured by the model: the one triggered by the multiple vibrational excitation of the bond and another which is due to excitation of one of the bonding electrons to an antibonding state by a solitary hot carrier. These processes are considered self-consistently as competing pathways of the same dissociation reaction. To analyze the importance of the EES process we use a series of nMOSFETs with identical architecture but different gate lengths. The gate length varies in the wide range of 44-300 nm to cover short-channel MOSFETs as well as their longer counterparts. According to previous findings, EES starts to become important at a channel length of 180 nm. This situation is captured in the targeted gate length interval. Our results show that the channel length alone is not a sufficient criterion on the importance of EES and that the applied bias conditions have to be taken into account as well.

  18. On Cu(II) Cu(II) distance measurements using pulsed electron electron double resonance

    Science.gov (United States)

    Yang, Zhongyu; Becker, James; Saxena, Sunil

    2007-10-01

    The effects of orientational selectivity on the 4-pulse electron electron double resonance (PELDOR) ESR spectra of coupled Cu(II)-Cu(II) spins are presented. The data were collected at four magnetic fields on a poly-proline peptide containing two Cu(II) centers. The Cu(II)-PELDOR spectra of this peptide do not change appreciably with magnetic field at X-band. The data were analyzed by adapting the theory of Maryasov, Tsvetkov, and Raap [A.G. Maryasov, Y.D. Tsvetkov, J. Raap, Weakly coupled radical pairs in solids:ELDOR in ESE structure studies, Appl. Magn. Reson. 14 (1998) 101-113]. Simulations indicate that orientational effects are important for Cu(II)-PELDOR. Based on simulations, the field-independence of the PELDOR data for this peptide is likely due to two effects. First, for this peptide, the Cu(II) g-tensor(s) are in a very specific orientation with respect to the interspin vector. Second, the flexibility of the peptide washes out the orientation effects. These effects reduce the suitability of the poly-proline based peptide as a good model system to experimentally probe orientational effects in such experiments. An average Cu(II)-Cu(II) distance of 2.1-2.2 nm was determined, which is consistent with earlier double quantum coherence ESR results.

  19. Distant retrograde orbits for the Moon's exploration

    Science.gov (United States)

    Sidorenko, Vladislav

    We discuss the properties of the distant retrograde orbits (which are called quasi-satellite orbits also) around Moon. For the first time the distant retrograde orbits were described by J.Jackson in studies on restricted three body problem at the beginning of 20th century [1]. In the synodic (rotating) reference frame distant retrograde orbit looks like an ellipse whose center is slowly drifting in the vicinity of minor primary body while in the inertial reference frame the third body is orbiting the major primary body. Although being away the Hill sphere the third body permanently stays close enough to the minor primary. Due to this reason the distant retrograde orbits are called “quasi-satellite” orbits (QS-orbits) too. Several asteroids in solar system are in a QS-orbit with respect to one of the planet. As an example we can mention the asteroid 2002VE68 which circumnavigates Venus [2]. Attention of specialists in space flight mechanics was attracted to QS-orbits after the publications of NASA technical reports devoted to periodic moon orbits [3,4]. Moving in QS-orbit the SC remains permanently (or at least for long enough time) in the vicinity of small celestial body even in the case when the Hill sphere lies beneath the surface of the body. The properties of the QS-orbit can be studied using the averaging of the motion equations [5,6,7]. From the theoretical point of view it is a specific case of 1:1 mean motion resonance. The integrals of the averaged equations become the parameters defining the secular evolution of the QS-orbit. If the trajectory is robust enough to small perturbations in the simplified problem (i.e., restricted three body problem) it may correspond to long-term stability of the real-world orbit. Our investigations demonstrate that under the proper choice of the initial conditions the QS-orbits don’t escape from Moon or don’t impact Moon for long enough time. These orbits can be recommended as a convenient technique for the large

  20. Snake Envenomation Causing Distant Tracheal Myonecrosis

    Science.gov (United States)

    Khimani, Amina; Mcnierney, Afton; Surani, Sara; Surani, Salim

    2013-01-01

    Snakebites are often believed to be poisonous. However, this is not always the case. In fact, each bite differs from snake to snake, depending on if the snake is poisonous and if there is envenomation. Venom in pit viper snakebites is often associated with local necrosis. The abundant literature selections and research articles justify local myonecrosis due to envenomation, but there is not much in the literature regarding myonecrosis at a site distant from the snakebite. We hereby present a case of a 42-year-old man who was transferred to our emergency department after a rattlesnake bit him twice. The patient, besides developing local myonecrosis at the site of the snakebite, developed necrosis of the scrotum as well as tracheal pressure myonecrosis at the site of the endotracheal tube balloon. In this review, we will attempt to discuss the myonecrosis pathophysiology and management related to the rattle snakebite. PMID:24083047

  1. Snake Envenomation Causing Distant Tracheal Myonecrosis

    Directory of Open Access Journals (Sweden)

    Amina Khimani

    2013-01-01

    Full Text Available Snakebites are often believed to be poisonous. However, this is not always the case. In fact, each bite differs from snake to snake, depending on if the snake is poisonous and if there is envenomation. Venom in pit viper snakebites is often associated with local necrosis. The abundant literature selections and research articles justify local myonecrosis due to envenomation, but there is not much in the literature regarding myonecrosis at a site distant from the snakebite. We hereby present a case of a 42-year-old man who was transferred to our emergency department after a rattlesnake bit him twice. The patient, besides developing local myonecrosis at the site of the snakebite, developed necrosis of the scrotum as well as tracheal pressure myonecrosis at the site of the endotracheal tube balloon. In this review, we will attempt to discuss the myonecrosis pathophysiology and management related to the rattle snakebite.

  2. Velocity fields of distant galaxies with FORS2 at the VLT

    CERN Document Server

    Ziegler, Bodo L; Da Rocha, Cristiano; Böhm, Asmus; Kapferer, Wolfgang; Kuntschner, Harald; Peletier, Reynier F; Schindler, Sabine; Verdugo, Miguel

    2009-01-01

    We describe a method to efficiently obtain two-dimensional velocity fields of distant, faint and small, emission-line galaxies with FORS2 at the VLT. They are examined for kinematic substructure to identify possible interaction processes. Numerical simulations of tidal interactions and ram-pressure effects reveal distinct signatures observable with our method. We detect a significant fraction of galaxies with irregular velocity fields both in the field and cluster environments.

  3. Controllable spin-orbit couplings of trapped electrons for distant quantum manipulations

    CERN Document Server

    Zhang, Miao

    2012-01-01

    Spin-orbit interactions of carriers yield various many-body quantum effects in the semiconducting physics. Here, we propose an approach to coherently manipulate spin-orbit interactions of electrons trapped on the liquid Helium at a single quantum level. The configuration consists of single electrons, confined individually on the liquid Helium by the micro-electrodes, moving along the surface as the harmonic oscillators. The spin of an electron could be coupled to its orbit (i.e., the vibrational motion) by properly applying a magnetic field. Interestingly, a Jaynes-Cummings (JC) type interaction between the spin of an electron and the vibrational motion of another distant electron is induced by virtually exciting the vibrational motion of the electron. With the present JC model, the quantum information processing between the spin qubits of the distant electrons could be effectively realized without moving the electrons. The proposal could be generlizedly applied to the other Fermi-Bosonic systems.

  4. Neutral sheet crossings in the distant magnetotail

    Energy Technology Data Exchange (ETDEWEB)

    Heikkila, W.J.; Slavin, J.A.; Smith, E.J.; Baker, D.N.; Zwickl, R.D.

    1985-01-01

    We have analyzed the magnetic field data from ISEE-3 in the distant magnetotail for 18 crossings of the cross-tail current sheet (or so-called natural sheet) to determine the direction of the normal component B/sub z/. The crossings occurred near the middle of the aberrated magnetotail (0 < y < 30 R/sub e, -10 < z < 5) in GSM coordinates, at a distance of about 220 R/sub e/, January 28 to February 12, 1983; in each case the plasma flow velocity was tailward. In 2 cases we found B/sub z/ negative (southward), as would be required with a magnetic neutral line (reconnection line) earthward of the spacecraft. In 12 cases B/sub z/ was clearly northward (B/sub z/ > 0.4 nT), consistent with closed field lines connected to the earth. In 3 cases B/sub z/ was very close to zero; in several instances there was structure in B/sub y/, suggesting localized currents with x or z directions. One may have been a magnetopause crossing. The strong preponderance of northward B/sub z/ favors a model of the magnetotail which is dominated by boundary layer plasma, flowing tailward on closed magnetic field lines, which requires the existence of an electric field in the sense from dusk to dawn. 37 refs., 15 figs., 1 tab.

  5. The Distant Type Ia Supernova Rate

    Science.gov (United States)

    Pain, R.; Fabbro, S.; Sullivan, M.; Ellis, R. S.; Aldering, G.; Astier, P.; Deustua, S. E.; Fruchter, A. S.; Goldhaber, G.; Goobar, A.; Groom, D. E.; Hardin, D.; Hook, I. M.; Howell, D. A.; Irwin, M. J.; Kim, A. G.; Kim, M. Y.; Knop, R. A.; Lee, J. C.; Perlmutter, S.; Ruiz-Lapuente, P.; Schahmaneche, K.; Schaefer, B.; Walton, N. A.

    2002-05-28

    We present a measurement of the rate of distant Type Ia supernovae derived using 4 large subsets of data from the Supernova Cosmology Project. Within this fiducial sample, which surveyed about 12 square degrees, thirty-eight supernovae were detected at redshifts 0.25--0.85. In a spatially flat cosmological model consistent with the results obtained by the Supernova Cosmology Project, we derive a rest-frame Type Ia supernova rate at a mean red shift z {approx_equal} 0.55 of 1.53 {sub -0.25}{sub -0.31}{sup 0.28}{sup 0.32} x 10{sup -4} h{sup 3} Mpc{sup -3} yr{sup -1} or 0.58{sub -0.09}{sub -0.09}{sup +0.10}{sup +0.10} h{sup 2} SNu(1 SNu = 1 supernova per century per 10{sup 10} L{sub B}sun), where the first uncertainty is statistical and the second includes systematic effects. The dependence of the rate on the assumed cosmological parameters is studied and the redshift dependence of the rate per unit comoving volume is contrasted with local estimates in the context of possible cosmic star formation histories and progenitor models.

  6. Distant Supernovae and the Accelerating Universe

    CERN Document Server

    Wright, E L

    2002-01-01

    The observation of SN 1997ff at redshift 1.7 has been claimed to refute alternative models such as grey dust or evolution for the faintness of distant supernovae, leaving only an accelerating Universe as a viable model. However, a very simple one parameter evolution model, with the peak luminosity varying as an exponential function of cosmic time, converts the flux vs. distance law of the critical density matter-dominated model into that of the concordance Omega_matter = 0.3 flat vacuum-dominated model with an error no larger than 0.03 mag over the range 0-2 in redshift. A grey dust model that matches this accuracy can easily be contrived but it still fails by overproducing the far-IR background or distorting the CMB. Models that involve oscillation between photons and axions could emulate an exponential function of cosmic time without violating these background constraints. Clearly a better and well-tested understanding of the Type Ia supernova explosion mechanism and the origin of the correlation between th...

  7. The distant Type Ia supernova rate

    CERN Document Server

    Pain, R; Sullivan, M; Ellis, Richard S; Aldering, G; Astier, Pierre; Duestua, S E; Fruchter, A S; Goldhaber, Gerson; Goobar, A; Groom, D E; Hardin, D; Hook, I M; Howell, D A; Irwin, M J; Kim, A G; Kim, M Y; Knop, R A; Lee, J C; Lidman, C E; McMahon, R G; Nugent, P; Panagia, N; Pennypacker, C R; Perlmutter, S; Ruiz-Lapuente, P; Schahmaneche, K; Schaefer, B; Walton, N A

    2001-01-01

    We present a measurement of the rate of distant Type Ia supernovae derived using 4 large subsets of data from the Supernova Cosmology Project. Within this fiducial sample, which surveyed about 12 square degrees, thirty-eight supernovae were detected at redshifts 0.25--0.85. In a spatially-flat cosmological model consistent with the results obtained by the Supernova Cosmology Project, we derive a rest-frame Type Ia supernova rate at a mean redshift $z\\simeq0.55$ of $1.53 {^{+0.28}_{-0.25}} {^{+0.32}_{-0.31}} 10^{-4} h^3 {\\rm Mpc}^{-3} {\\rm yr}^{-1}$ or $0.58 {^{+0.10}_{-0.09}} {^{+0.10}_{-0.09}} h^2 {\\rm SNu}$ (1 SNu = 1 supernova per century per $10^{10}$\\Lbsun), where the first uncertainty is statistical and the second includes systematic effects. The dependence of the rate on the assumed cosmological parameters is studied and the redshift dependence of the rate per unit comoving volume is contrasted with local estimates in the context of possible cosmic star formation histories and progenitor models.

  8. Distant retrograde orbits and the asteroid hazard

    Science.gov (United States)

    Perozzi, Ettore; Ceccaroni, Marta; Valsecchi, Giovanni B.; Rossi, Alessandro

    2017-08-01

    Distant Retrograde Orbits (DROs) gained a novel wave of fame in space mission design because of their numerous advantages within the framework of the US plans for bringing a large asteroid sample in the vicinity of the Earth as the next target for human exploration. DROs are stable solutions of the three-body problem that can be used whenever an object, whether of natural or artificial nature, is required to remain in the neighborhood of a celestial body without being gravitationally captured by it. As such, they represent an alternative option to Halo orbits around the collinear Lagrangian points L1 and L2. Also known under other names ( e.g., quasi-satellite orbits, cis-lunar orbits, family- f orbits) these orbital configurations found interesting applications in several mission profiles, like that of a spacecraft orbiting around the small irregularly shaped satellite of Mars Phobos or the large Jovian moon Europa. In this paper a basic explanation of the DRO dynamics is presented in order to clarify some geometrical properties that characterize them. Their accessibility is then discussed from the point of view of mission analysis under different assumptions. Finally, their relevance within the framework of the present asteroid hazard protection programs is shown, stressing the significant increase in warning time they would provide in the prediction of impactors coming from the direction of the Sun.

  9. A split-step method to include electron-electron collisions via Monte Carlo in multiple rate equation simulations

    Science.gov (United States)

    Huthmacher, Klaus; Molberg, Andreas K.; Rethfeld, Bärbel; Gulley, Jeremy R.

    2016-10-01

    A split-step numerical method for calculating ultrafast free-electron dynamics in dielectrics is introduced. The two split steps, independently programmed in C++11 and FORTRAN 2003, are interfaced via the presented open source wrapper. The first step solves a deterministic extended multi-rate equation for the ionization, electron-phonon collisions, and single photon absorption by free-carriers. The second step is stochastic and models electron-electron collisions using Monte-Carlo techniques. This combination of deterministic and stochastic approaches is a unique and efficient method of calculating the nonlinear dynamics of 3D materials exposed to high intensity ultrashort pulses. Results from simulations solving the proposed model demonstrate how electron-electron scattering relaxes the non-equilibrium electron distribution on the femtosecond time scale.

  10. Femtosecond spectroscopy of electron-electron and electron-phonon energy relaxation in Ag and Au

    Science.gov (United States)

    Groeneveld, Rogier H. M.; Sprik, Rudolf; Lagendijk, Ad

    1995-05-01

    We show experimentally that the electron distribution of a laser-heated metal is a nonthermal distribution on the time scale of the electron-phonon (e-ph) energy relaxation time τE. We measured τE in 45-nm Ag and 30-nm Au thin films as a function of lattice temperature (Ti=10-300 K) and laser-energy density (Ul=0.3-1.3 J cm-3), combining femtosecond optical transient-reflection techniques with the surface-plasmon polariton resonance. The experimental effective e-ph energy relaxation time decreased from 710-530 fs and 830-530 fs for Ag and Au, respectively, when temperature is lowered from 300 to 10 K. At various temperatures we varied Ul between 0.3-1.3 J cm-3 and observed that τE is independent from Ul within the given range. The results were first compared to theoretical predictions of the two-temperature model (TTM). The TTM is the generally accepted model for e-ph energy relaxation and is based on the assumption that electrons and lattice can be described by two different time-dependent temperatures Te and Ti, implying that the two subsystems each have a thermal distribution. The TTM predicts a quasiproportional relation between τE and Ti in the perturbative regime where τE is not affected by Ul. Hence, it is shown that the measured dependencies of τE on lattice temperature and energy density are incompatible with the TTM. It is proven that the TTM assumption of a thermal electron distribution does not hold especially under our experimental conditions of low laser power and lattice temperature. The electron distribution is a nonthermal distribution on the picosecond time scale of e-ph energy relaxation. We developed a new model, the nonthermal electron model (NEM), in which we account for the (finite) electron-electron (e-e) and electron-phonon dynamics simultaneously. It is demonstrated that incomplete electron thermalization yields a slower e-ph energy relaxation in comparison to the thermalized limit. With the NEM we are able to give a consistent

  11. Grounded Eyes on Distant Watery Skies

    Science.gov (United States)

    Kohler, Susanna

    2017-08-01

    , the authorshigh-resolution observations allowed them to resolve not only the stellar spectrum, but also the spectral lines fromthe hot Jupiter exoplanet itself.Obtaining a thermal spectrum of the planet permitted the team to break the usual observational degeneracy that occurs with exoplanet observations: they were able to disentangle the planet mass and its orbital inclination angle. Piskorz and collaborators found that the planet is roughly 1.7 Jupiter masses and its orbit is inclined 24 relative to our line of sight.Artists illustration of the closest three planets in the upsilon Andromedae system. The system also has a distant red-dwarf binary companion, as well as a possible fourth planet. [NASA/ESA/A. Feild (STScI)]These measurements of the orbital structure of upsilon Andromedae are critical for understanding this unusual system. With non-coplanar planets and a distant red-dwarf companion, the upsilon Andromedae system has long been suspected to lie on the precipice of instability. The new measurements of upsilon Andromeda bs orbital properties will help us to better understand how the system may have formed, evolved, and survived to today.Water FoundOne of the biggest benefits of spectroscopy of an exoplanet is the potentialto learn about its atmospheric composition. Using their NIRSPEC observations of upsilon Andromedae b and detailed atmospheric modeling, Piskorz and collaborators found that the planets opacity structure is dominated by water vapor at the wavelengths they probed.This detection of water vapor in upsilon Andromedae bs atmosphere and the constraints on the planets orbital properties demonstrate the power and potential of ground-based, high-resolution spectroscopy for characterizing exoplanets and constraining the architecture of distantsolar systems.CitationDanielle Piskorz et al 2017 AJ 154 78. doi:10.3847/1538-3881/aa7dd8

  12. Attractive electron-electron interactions at the LaAlO3/SrTiO3 Interface

    DEFF Research Database (Denmark)

    Prawiroatmodjo, Guenevere E D K

    The conducting interface between the two insulating oxides LaAlO3 and SrTiO3 (LAO/STO) exhibits many intriguing properties such as high mobility, a gate-tunable superconducting phase, ferroelectricity and ferromagnetism. In this thesis, devices are fabricated at the LAO/STO interface using novel...... hard-mask patterning techniques with micrometer precision. The superconducting phase diagram is explored in terms of critical magnetic field Bc, temperature Tc and current Ic, and studied for varying carrier densities. From a finite shift between the superconducting Tc and Ic domes, evidence is found...

  13. GW approach to electron-electron interactions within the Anderson impurity model: Kondo correlated quantum transport through two coupled molecules

    Science.gov (United States)

    Aksu, H.; Goker, A.

    2017-03-01

    We invoke the nonequilibrium self-consistent GW method within the Anderson impurity model to investigate the dynamical effects occurring in a nanojunction comprised of two coupled molecules. Contrary to the previous single impurity model calculations based on the GW approximation, we observe that the density of states manages to capture both the Kondo resonance and the Breit-Wigner resonances associated with the HOMO and LUMO levels of the molecule. Moreover, the prominence of the Kondo resonance grows dramatically upon switching from the intermediate to the weak coupling regime involving large U / Γ values. The conductance is calculated as a function of the HOMO level and the applied bias across the molecular nanojunction. Calculated conductance curves deviate from the monotonic decay behaviour as a function of the bias when the half-filling condition is not met. The importance of the effect of the molecule-molecule coupling for the electron transport phenomena is also investigated.

  14. ROSAT Discovers Unique, Distant Cluster of Galaxies

    Science.gov (United States)

    1995-06-01

    Brightest X-ray Cluster Acts as Strong Gravitational Lens Based on exciting new data obtained with the ROSAT X-ray satellite and a ground-based telescope at the ESO La Silla Observatory, a team of European astronomers [2] has just discovered a very distant cluster of galaxies with unique properties. It emits the strongest X-ray emission of any cluster ever observed by ROSAT and is accompanied by two extraordinarily luminous arcs that represent the gravitationally deflected images of even more distant objects. The combination of these unusual characteristics makes this cluster, now known as RXJ1347.5-1145, a most interesting object for further cosmological studies. DISCOVERY AND FOLLOW-UP OBSERVATIONS This strange cluster of galaxies was discovered during the All Sky Survey with the ROSAT X-ray satellite as a moderately intense X-ray source in the constellation of Virgo. It could not be identified with any already known object and additional ground-based observations were therefore soon after performed with the Max-Planck-Society/ESO 2.2-metre telescope at the La Silla observatory in Chile. These observations took place within a large--scale redshift survey of X-ray clusters of galaxies detected by the ROSAT All Sky Survey, a so-called ``ESO Key Programme'' led by astronomers from the Max-Planck-Institut fur Extraterrestrische Physik and the Osservatorio Astronomico di Brera. The main aim of this programme is to identify cluster X-ray sources, to determine the distance to the X-ray emitting clusters and to investigate their overall properties. These observations permitted to measure the redshift of the RXJ1347.5-1145 cluster as z = 0.45, i.e. it moves away from us with a velocity (about 106,000 km/sec) equal to about one-third of the velocity of light. This is an effect of the general expansion of the universe and it allows to determine the distance as about 5,000 million light-years (assuming a Hubble constant of 75 km/sec/Mpc). In other words, we see these

  15. The position of cytochrome b(559) relative to Q(A) in photosystem II studied by electron-electron double resonance (ELDOR).

    Science.gov (United States)

    Kuroiwa, S; Tonaka, M; Kawamori, A; Akabori, K

    2000-11-20

    The electron-electron double resonance (ELDOR) method was applied to measure the dipole interaction between cytochrome (Cyt) b(+)(559) and the primary acceptor quinone (Q(-)(A)), observed at g=2.0045 with the peak to peak width of about 9 G, in Photosystem II (PS II) in which the non-heme Fe(2+) was substituted by Zn(2+). The paramagnetic centers of Cyt b(+)(559)Y(D)Q(-)(A) were trapped by illumination at 273 K for 8 min, followed by dark adaptation for 3 min and freezing into 77 K. The distance between the pair Cyt b(+)(559)-Q(-)(A) was estimated from the dipole interaction constant fitted to the observed ELDOR time profile to be 40+/-1 A. In the membrane oriented PS II particles the angle between the vector from Q(A) to Cyt b(559) and the membrane normal was determined to be 80+/-5 degrees. The position of Cyt b(559) relative to Q(A) suggests that the heme plane is located on the stromal side of the thylakoid membrane. ELDOR was not observed for Cyt b(+)(559) Y(D) spin pair, suggesting the distance between them is more than 50 A.

  16. A molecular study of microbe transfer between distant environments.

    Directory of Open Access Journals (Sweden)

    Sean D Hooper

    Full Text Available BACKGROUND: Environments and their organic content are generally not static and isolated, but in a constant state of exchange and interaction with each other. Through physical or biological processes, organisms, especially microbes, may be transferred between environments whose characteristics may be quite different. The transferred microbes may not survive in their new environment, but their DNA will be deposited. In this study, we compare two environmental sequencing projects to find molecular evidence of transfer of microbes over vast geographical distances. METHODOLOGY: By studying synonymous nucleotide composition, oligomer frequency and orthology between predicted genes in metagenomics data from two environments, terrestrial and aquatic, and by correlating with phylogenetic mappings, we find that both environments are likely to contain trace amounts of microbes which have been far removed from their original habitat. We also suggest a bias in direction from soil to sea, which is consistent with the cycles of planetary wind and water. CONCLUSIONS: Our findings support the Baas-Becking hypothesis formulated in 1934, which states that due to dispersion and population sizes, microbes are likely to be found in widely disparate environments. Furthermore, the availability of genetic material from distant environments is a possible font of novel gene functions for lateral gene transfer.

  17. Distant Influence of Kuroshio Eddies on North Pacific Weather Patterns?

    Science.gov (United States)

    Ma, Xiaohui; Chang, Ping; Saravanan, R.; Montuoro, Raffaele; Hsieh, Jen-Shan; Wu, Dexing; Lin, Xiaopei; Wu, Lixin; Jing, Zhao

    2015-12-01

    High-resolution satellite measurements of surface winds and sea-surface temperature (SST) reveal strong coupling between meso-scale ocean eddies and near-surface atmospheric flow over eddy-rich oceanic regions, such as the Kuroshio and Gulf Stream, highlighting the importance of meso-scale oceanic features in forcing the atmospheric planetary boundary layer (PBL). Here, we present high-resolution regional climate modeling results, supported by observational analyses, demonstrating that meso-scale SST variability, largely confined in the Kuroshio-Oyashio confluence region (KOCR), can further exert a significant distant influence on winter rainfall variability along the U.S. Northern Pacific coast. The presence of meso-scale SST anomalies enhances the diabatic conversion of latent heat energy to transient eddy energy, intensifying winter cyclogenesis via moist baroclinic instability, which in turn leads to an equivalent barotropic downstream anticyclone anomaly with reduced rainfall. The finding points to the potential of improving forecasts of extratropical winter cyclones and storm systems and projections of their response to future climate change, which are known to have major social and economic impacts, by improving the representation of ocean eddy-atmosphere interaction in forecast and climate models.

  18. Distant future of the Sun and Earth revisited

    CERN Document Server

    Schroder, Klaus-Peter

    2008-01-01

    We revisit the distant future of the Sun and the solar system, based on stellar models computed with a thoroughly tested evolution code. For the solar giant stages, mass-loss by the cool (but not dust-driven) wind is considered in detail. Using the new and well-calibrated mass-loss formula of Schroder & Cuntz (2005, 2007), we find that the mass lost by the Sun as an RGB giant (0.332 M_Sun, 7.59 Gy from now) potentially gives planet Earth a significant orbital expansion, inversely proportional to the remaining solar mass. According to these solar evolution models, the closest encounter of planet Earth with the solar cool giant photosphere will occur during the tip-RGB phase. During this critical episode, for each time-step of the evolution model, we consider the loss of orbital angular momentum suffered by planet Earth from tidal interaction with the giant Sun, as well as dynamical drag in the lower chromosphere. We find that planet Earth will not be able to escape engulfment, despite the positive effect o...

  19. Distant collaboration in drug discovery: The LINK3D project

    Science.gov (United States)

    Pastor, Manuel; Benedetti, Paolo; Carotti, Angelo; Carrieri, Antonio; Díaz, Carlos; Herráiz, Cristina; Höltje, Hans-Dieter; Loza, M. Isabel; Oprea, Tudor; Padín, Fernando; Pubill, Francesc; Sanz, Ferran; Stoll, Friederike; the LINK3D Consortium

    2002-11-01

    The work describes the development of novel software supporting synchronous distant collaboration between scientists involved in drug discovery and development projects. The program allows to visualize and share data as well as to interact in real time using standard intranets and Internet resources. Direct visualization of 2D and 3D molecular structures is supported and original tools for facilitating remote discussion have been integrated. The software is multiplatform (MS-Windows, SGI-IRIX, Linux), allowing for a seamless integration of heterogeneous working environments. The project aims to support collaboration both within and between academic and industrial institutions. Since confidentiality is very important in some scenarios, special attention has been paid to security aspects. The article presents the research carried out to gather the requirements of collaborative software in the field of drug discovery and development and describes the features of the first fully functional prototype obtained. Real-world testing activities carried out on this prototype in order to guarantee its adequacy in diverse environments are also described and discussed.

  20. Distant X-ray Galaxies: Insights from the Local Population

    CERN Document Server

    Moran, E C

    2004-01-01

    A full understanding of the origin of the hard X-ray background requires a complete and accurate census of the distant galaxies that produce it. Unfortunately, distant X-ray galaxies tend to be very faint at all wavelengths, which hinders efforts to perform this census. This chapter discusses the insights that can be obtained through comparison of the distant population to local X-ray galaxies, whose properties are well characterized. Such comparisons will ultimately aid investigations into the cosmic evolution of supermassive black holes and their environments.

  1. LIVE DEMONSTRATION OF DISTANT EARLY WARNING SYSTEM

    Science.gov (United States)

    Hammitzsch, M.; Lendholt, M.; Wächter, J.

    2009-12-01

    The DEWS (Distant Early Warning System) [1] project, funded under the 6th Framework Programme of the European Union, has the objective to create a new generation of interoperable early warning systems based on an open sensor platform. This platform integrates OGC [2] SWE [3] compliant sensor systems for the rapid detection of earthquakes, for the monitoring of sea level, ocean floor events, and ground displacements. Based on the upstream information flow DEWS focuses on the improvement of downstream capacities of warning centres especially by improving information logistics for effective and targeted warning message aggregation for a multilingual environment. Multiple telecommunication channels will be used for the dissemination of warning messages. Wherever possible, existing standards have been integrated. The Command and Control User Interface (CCUI), a rich client application based on Eclipse RCP (Rich Client Platform) [4] and the open source GIS uDig [5], integrates various OGC services. Using WMS (Web Map Service) [6] and WFS (Web Feature Service) [7] spatial data are utilized to depict the situation picture and to integrate a simulation system via WPS (Web Processing Service) [8] to identify affected areas. Warning messages are compiled and transmitted in the OASIS [9] CAP (Common Alerting Protocol) [10] standard together with addressing information defined via EDXL-DE (Emergency Data Exchange Language - Distribution Element) [11]. Internal interfaces are realized with SOAP [12] web services. Based on results of GITEWS [13] - in particular the GITEWS Tsunami Service Bus [14] - the DEWS approach provides an implementation for tsunami early warning systems. The introductory part of the demonstration briefly explains the DEWS project, the CCUI in conjunction with operators’ workflow, the system architecture, details of information logistics and the virtual scenario of live demonstration. The live demonstration exhibits the CCUI on screen and the service

  2. Distant education of gifted children in the USA

    Directory of Open Access Journals (Sweden)

    Rogozhkina I. B.

    2012-06-01

    Full Text Available Distant teaching which helps to realize the main principles of contemporary education: «teaching throughout» and «lifelong teaching» becomes more and more indemand. The possibility to get education for the residents of remote districts, excess to contemporary data bases, scientific libraries and learning materials of high quality, possibility to study at a time convenient for a student and in a tempo acceptable to the one makes distant education one of the most effective form of work with gifted children. System of distant education in the USA which is one of the most sophisticated one involves a big variety of programs and courses for both ordinary and gifted students. The article analyzes the existing in the USA on-line programs for gifted children, reveals their advantages and disadvantages, discusses the distant forms of work applicable to teaching of gifted children in Russia.

  3. Distant Supernovae Indicate Ever-Expanding Universe

    Science.gov (United States)

    1998-12-01

    ,000 million light-years) is observed on five dates with the SUSI camera at the 3.6-m New Technology Telescope (NTT). The host galaxy is clearly visible and the supernova reaches its maximum brightness around 13 March 1997, after which it fades. In PR Photo 50b/98 of another supernova that was found at the same time, the image of the host galaxy is barely visible, most probably because it is a low surface brightness galaxy . Here, the redshift of the supernova is z = 0.40 (distance 6,000 million light-years) and the brightness peaks around 16 March 1997. Technical information: All images were obtained through an R (red) optical filtre. The image quality varies somewhat from image to image. Exposure times and seeing values: Photo 50a/98 - 11 March (300 sec; 0.73 arcsec); 13 March (600 sec; 0.79 arcsec); 16 March (600 sec; 0.72 arcsec); 29 March (1200 sec; 1.17 arcsec); 5 April (300 sec; 0.55 arcsec) and Photo 50b/98 - 11 March (300 sec; 0.50 arcsec); 13 March (600 sec; 0.81 arcsec); 16 March (600 sec; 0.90 arcsec); 29 March (1200 sec; 0.83 arcsec); 7 April (300 sec; 1.43 arcsec); 7 May (1800 sec; 1.22 arcsec). These explosions, known as Type Ia Supernovae , are distinguished by their very uniform properties, including their intrinsic brightness; this makes them ideal for the measurement of large distances, cf. ESO PR Photos 50a/98 and 50b/98 , as well as ESO Press Release 09/95. It is by means of observations of remote objects of this type that the all-important distances could be determined with sufficient accuracy. In particular, coordinated observing campaigns of Type Ia Supernovae were carried out at several of the world's major observatories. In this way it became possible to secure the crucial data that provide the basis of the new analysis. Distances to Type Ia Supernovae are larger than expected The new observations show that, compared to their nearby twins, distant supernovae appear too dim, even for a Universe which has been freely coasting (i.e. with no change of the

  4. Very-high-energy gamma rays from a distant quasar: how transparent is the universe?

    Science.gov (United States)

    Albert, J; Aliu, E; Anderhub, H; Antonelli, L A; Antoranz, P; Backes, M; Baixeras, C; Barrio, J A; Bartko, H; Bastieri, D; Becker, J K; Bednarek, W; Berger, K; Bernardini, E; Bigongiari, C; Biland, A; Bock, R K; Bonnoli, G; Bordas, P; Bosch-Ramon, V; Bretz, T; Britvitch, I; Camara, M; Carmona, E; Chilingarian, A; Commichau, S; Contreras, J L; Cortina, J; Costado, M T; Covino, S; Curtef, V; Dazzi, F; De Angelis, A; De Cea Del Pozo, E; de Los Reyes, R; De Lotto, B; De Maria, M; De Sabata, F; Mendez, C Delgado; Dominguez, A; Dorner, D; Doro, M; Errando, M; Fagiolini, M; Ferenc, D; Fernández, E; Firpo, R; Fonseca, M V; Font, L; Galante, N; López, R J García; Garczarczyk, M; Gaug, M; Goebel, F; Hayashida, M; Herrero, A; Höhne, D; Hose, J; Hsu, C C; Huber, S; Jogler, T; Kneiske, T M; Kranich, D; La Barbera, A; Laille, A; Leonardo, E; Lindfors, E; Lombardi, S; Longo, F; López, M; Lorenz, E; Majumdar, P; Maneva, G; Mankuzhiyil, N; Mannheim, K; Maraschi, L; Mariotti, M; Martínez, M; Mazin, D; Meucci, M; Meyer, M; Miranda, J M; Mirzoyan, R; Mizobuchi, S; Moles, M; Moralejo, A; Nieto, D; Nilsson, K; Ninkovic, J; Otte, N; Oya, I; Panniello, M; Paoletti, R; Paredes, J M; Pasanen, M; Pascoli, D; Pauss, F; Pegna, R G; Perez-Torres, M A; Persic, M; Peruzzo, L; Piccioli, A; Prada, F; Prandini, E; Puchades, N; Raymers, A; Rhode, W; Ribó, M; Rico, J; Rissi, M; Robert, A; Rügamer, S; Saggion, A; Saito, T Y; Salvati, M; Sanchez-Conde, M; Sartori, P; Satalecka, K; Scalzotto, V; Scapin, V; Schmitt, R; Schweizer, T; Shayduk, M; Shinozaki, K; Shore, S N; Sidro, N; Sierpowska-Bartosik, A; Sillanpää, A; Sobczynska, D; Spanier, F; Stamerra, A; Stark, L S; Takalo, L; Tavecchio, F; Temnikov, P; Tescaro, D; Teshima, M; Tluczykont, M; Torres, D F; Turini, N; Vankov, H; Venturini, A; Vitale, V; Wagner, R M; Wittek, W; Zabalza, V; Zandanel, F; Zanin, R; Zapatero, J

    2008-06-27

    The atmospheric Cherenkov gamma-ray telescope MAGIC, designed for a low-energy threshold, has detected very-high-energy gamma rays from a giant flare of the distant Quasi-Stellar Radio Source (in short: radio quasar) 3C 279, at a distance of more than 5 billion light-years (a redshift of 0.536). No quasar has been observed previously in very-high-energy gamma radiation, and this is also the most distant object detected emitting gamma rays above 50 gigaelectron volts. Because high-energy gamma rays may be stopped by interacting with the diffuse background light in the universe, the observations by MAGIC imply a low amount for such light, consistent with that known from galaxy counts.

  5. Distant Radio Galaxies and their Environments

    CERN Document Server

    Miley, George

    2008-01-01

    We review the properties and nature of luminous high-redshift radio galaxies (HzRGs, z > 2) and the environments in which they are located. HzRGs have several distinct constituents which interact with each other - relativistic plasma, gas in various forms, dust, stars and an active galactic nucleus (AGN). These building blocks provide unique diagnostics about conditions in the early Universe. We discuss the properties of each constituent. Evidence is presented that HzRGs are massive forming galaxies and the progenitors of brightest cluster galaxies in the local Universe. HzRGs are located in overdense regions in the early Universe and are frequently surrounded by protoclusters. We review the properties and nature of these radio-selected protoclusters. Finally we consider the potential for future progress in the field during the next few decades. A compendium of known HzRGs is given in an appendix.

  6. Plasma electrons as tracers of distant magnetotail structure: ISEE-3

    Energy Technology Data Exchange (ETDEWEB)

    Baker, D.N.; Bame, S.J.; Gosling, J.T.; Gussenhoven, M.S.

    1988-01-01

    Electrons in the 50-500 eV energy range commonly exhibit strong, field-aligned bidirectional anisotropies in the distant (r > 100 Rg) geomagnetic tail lobes and are found to occur predominantly in the lobe directly connected to the sun along the interplanetary magnetic field in the open magnetosphere model (north lobe for away interplanetary sectors and south lobe for toward sectors). Data show the transition from unidirectional (sheath) electron populations to bidirectional (lobe) populations at the distant magnetopause. This demonstrates the open nature of the distant magnetotail and shows that the source of the higher-energy, bidirectional lobe electrons is the tailward-directed electron heat flux population in the magnetosheath. The field-aligned lobe electron phase space densities above 200 eV at ISEE-3 agree well with DMSP-measured polar rain phase space densities near the polar cap and the spectral slopes above 200 eV also are similar. Below 100-200 eV there is a thermal electron population in the distant tail, arising from local entry of plasma through the distant magnetopause, which is not present at DMSP altitudes. These data show that the suprathermal tail lobe electrons are essentially a test particle population which can move freely along field lines to form polar rain; in contrast, the thermal electrons are bound to the tailward-flowing lobe ion population far down the tail and thus cannot reach the polar cap regions.

  7. Myeloid-derived suppressor cells (MDSC) facilitate distant metastasis of malignancies by shielding circulating tumor cells (CTC) from immune surveillance.

    Science.gov (United States)

    Liu, Qiaofei; Liao, Quan; Zhao, Yupei

    2016-02-01

    The mechanisms of distant metastasis of malignancies largely remain unknown. Circulating tumor cells (CTC) derived from the primary cancer initiate distant metastasis by entering and traversing the bloodstream. Current methods to detect CTC are based on the notion that CTC do not express the common leukocyte antigen CD45. However, these methods neglect the fact that CTC can directly adhere to platelets and immune cells and therefore appear to be CD45-positive. The potential effects of interactions between CTC and adhesive immune cells have been largely overlooked, despite the fact that most CTC are killed by immune effector cells and only those that evade immune surveillance result in clonal expansion and metastatic lesions. It is crucial to define the characteristics that allow a select CTC population to escape immune surveillance; particularly, it must be determined whether interactions between CTC and adhesive immune cells provide a protective effect on CTC survival. If interactions between CTC and adhesive immune cells offer a selective advantage to those CTC cells, the next consideration is which characteristics of a CTC-immune cell population allow sufficient protection to facilitate immune evasion. Myeloid-derived suppressor cells (MDSC) are a large heterogeneous population of immature myeloid cells that accumulate during cancer progression to induce extensively systemic and local immunosuppression, a phenomenon that has been demonstrated to facilitate cancer distant metastasis. We hypothesize, therefore, that CTC populations interacting with adhesive immune cells will have different biological behavior than CTC populations alone. Further, we hypothesize that CTC can create a defensive shield consisting of adhesive MDSC, which allows evasion of immune surveillance and therefore facilitates distant metastatic lesions. This possibility highlights the importance of direct interactions between CTC and adhesive immune cells and suggests the potential target that

  8. Entanglement dynamics of electron-electron scattering in low-dimensional semiconductor systems

    CERN Document Server

    Buscemi, F; Bordone, P; Bertoni, Andrea; Bordone, Paolo; Buscemi, Fabrizio

    2006-01-01

    We perform the quantitative evaluation of the entanglement dynamics in scattering events between two insistinguishable electrons interacting via Coulomb potential in 1D and 2D semiconductor nanostructures. We apply a criterion based on the von Neumann entropy and the Schmidt decomposition of the global state vector suitable for systems of identical particles. From the timedependent numerical solution of the two-particle wavefunction of the scattering carriers we compute their entanglement evolution for different spin configurations: two electrons with the same spin, with different spin, singlet, and triplet spin state. The procedure allows to evaluate the mechanisms that govern entanglement creation and their connection with the characteristic physical parameters and initial conditions of the system. The cases in which the evolution of entanglement is similar to the one obtained for distinguishable particles are discussed.

  9. Electron--electron correlations assessed analyzing doubly differential angular distributions in double ionization of helium by proton impact

    Science.gov (United States)

    Ciappina, Marcelo; Schulz, Michael; Kirchner, Tom; Fischer, Daniel; Moshammer, Robert; Ullrich, Joachim

    2008-10-01

    Double ionization (DI) of helium by ion impact presents a singular scenario to study electron-electron correlation in atomic physics. Recent experimental data have revealed signatures of this feature in the doubly differential cross sections in terms of the angles of the two emitted electrons [1]. We present an exhaustive theoretical and experimental study of these cross sections, by disentangling the contribution of the different mechanisms that contribute to DI [2]. To this end, first order and higher order distorted wave theories are implemented jointly with the Monte Carlo Event Generator method (MCEG) [3]. This latter tool allows us to incorporate efficiently all the experimental conditions in the theoretical models. [1] M. Schulz et al, J. Phys. B 38, 1363-1370 (2005). [2] M. F. Ciappina et al, PRA (in preparation) (2008). [3] M. D"urr et al, Phys. Rev. A 75, 062708 (2007).

  10. Marketing of coaches' distant improvement of professional skills

    Directory of Open Access Journals (Sweden)

    Petrova О.A.

    2012-04-01

    Full Text Available By means of marketing researches influence of political, legal, economic, scientific and technical and socially-demographic factors on system of coaches' distant improvement of professional skills is analyzed. Estimations of 12 experts were used for the lead through of marketing «PETS»- analysis and constructions of matrix of «SWOT»-analysis. The expediency of introduction of system of Ukrainian coaches distant improvement of professional skills is defined, are revealed strong and weaknesses, threats and favorable possibilities of the given system for physical training and sports sphere in Ukraine. The influence of threatening factors almost in 2,5 times less than, than factors of favorable possibilities of development of the system of coaches' distant improvement of professional skills is set.

  11. Phase-Tuned Entangled State Generation between Distant Spin Qubits

    Science.gov (United States)

    Stockill, R.; Stanley, M. J.; Huthmacher, L.; Clarke, E.; Hugues, M.; Miller, A. J.; Matthiesen, C.; Le Gall, C.; Atatüre, M.

    2017-07-01

    Quantum entanglement between distant qubits is an important feature of quantum networks. Distribution of entanglement over long distances can be enabled through coherently interfacing qubit pairs via photonic channels. Here, we report the realization of optically generated quantum entanglement between electron spin qubits confined in two distant semiconductor quantum dots. The protocol relies on spin-photon entanglement in the trionic Λ system and quantum erasure of the Raman-photon path information. The measurement of a single Raman photon is used to project the spin qubits into a joint quantum state with an interferometrically stabilized and tunable relative phase. We report an average Bell-state fidelity for |ψ(+)⟩ and |ψ(-)⟩ states of 61.6 ±2.3 % and a record-high entanglement generation rate of 7.3 kHz between distant qubits.

  12. Effects of cholesterol on lateral diffusion and vertical fluctuations in lipid bilayers. An electron-electron double resonance (ELDOR) study

    Energy Technology Data Exchange (ETDEWEB)

    Yin, J.J.; Feix, J.B.; Hyde, J.S.

    1987-12-01

    Electron-electron double resonance (ELDOR) and saturation-recovery spectroscopy employing /sup 14/N:/sup 15/N stearic acid spin-label pairs have been used to study the effects of cholesterol on lateral diffusion and vertical fluctuations in lipid bilayers. The /sup 14/N:/sup 15/N continuous wave electron-electron double resonance (CW ELDOR) theory has been developed using rate equations based on the relaxation model. The collision frequency between /sup 14/N-16 doxyl stearate and /sup 15/N-16 doxyl stearate, WHex (16:16), is indicative of lateral diffusion of the spin probes, while the collision frequency between /sup 14/N-16 doxyl stearate and /sup 15/N-5 doxyl stearate, WHex (16:5), provides information on vertical fluctuations of the /sup 14/N-16 doxyl stearate spin probe toward the membrane surface. Our results show that: (a) cholesterol decreases the electron spin-lattice relaxation time Tle of /sup 14/N-16 doxyl stearate spin label in dimyristoylphosphatidylcholine (DMPC) and egg yolk phosphatidylcholine (egg PC). (b) Cholesterol increases the biomolecular collision frequency WHex (16:16) and decreases WHex (16:5), suggesting that incorporation of cholesterol significantly orders the part of the bilayer that it occupies and disorders the interior region of the bilayer. (c) Alkyl chain unsaturation of the host lipid moderates the effect of cholesterol on both vertical fluctuations and lateral diffusion of /sup 14/N-16 doxyl stearate. And (d), there are marked differences in the effects of cholesterol on lateral diffusion and vertical fluctuations between 0-30 mol% and 30-50 mol% of cholesterol that suggest an inhomogeneous distribution of cholesterol in the membrane.

  13. Relative-locality distant observers and the phenomenology of momentum-space geometry

    Science.gov (United States)

    Amelino-Camelia, Giovanni; Arzano, Michele; Kowalski-Glikman, Jerzy; Rosati, Giacomo; Trevisan, Gabriele

    2012-04-01

    We study the translational invariance of the relative-locality framework proposed in Amelino-Camelia et al (2011 Phys. Rev. D 84 084010), which had been previously established only for the case of a single interaction. We provide an explicit example of boundary conditions at endpoints of worldlines, which indeed ensures the desired translational invariance for processes involving several interactions, even when some of the interactions are causally connected (particle exchange). We illustrate the properties of the associated relativistic description of distant observers within the example of a κ-Poincaré-inspired momentum-space geometry, with de Sitter metric and parallel transport governed by a non-metric and torsionful connection. We find that in such a theory, simultaneously emitted massless particles do not reach simultaneously a distant detector, as expected in light of the findings of Freidel and Smolin (2011 arXiv:1103.5626) on the implications of non-metric connections. We also show that the theory admits a free-particle limit, where the relative-locality results of Amelino-Camelia et al (2011 Phys. Lett. B 700 150) are reproduced. We establish that the torsion of the κ-Poincaré connection introduces a small (but observably large) dependence of the time of detection, for simultaneously emitted particles, on some properties of the interactions producing the particles at the source.

  14. MOODLE – COMPUTERIZED DISTANT LEARNING SUPPORT SYSTEM

    Directory of Open Access Journals (Sweden)

    V. A. Tunda

    2014-01-01

    Full Text Available Moodle (Modular Object-Oriented Dynamic Learning Environment is the system developed by the English-speaking community around the world for more than 10 years, supports both, offline and online training. In most cases, Moodle is used to support and connect learning face-to-face with online training, as well as with other types of learning. Moodle allows you to ask all sorts of questions and assess responses in a variety of ways. The central concept of Moodle is a course in which one or more teachers offer students resources (such as files, folders, Web pages and participate in interactive activities (such as forums, wikis, blogging, lessons, seminars, assignments, examinations. Students and teachers can change roles, mutually assess each other, share knowledge on the topics of study in the glossary and database system.In the English-speaking world, there are public sites with detailed documentation on Moodle, which is constantly verified and modified in accordance with emerging new versions of the system; Russian versions do not have public sites with detailed translation of the English-language documentation. On what and to whom you want to perform actions in the daily practice of the modern versions, only the barest of outlines on paid seminars and presentations to those who started the implementation of Moodle in your organization are given. And this despite the fact that the system has a great variety of Moodle (over 500 settings with different levels of functionality to be performed, to maintain and develop specially organized by the team of specialists. The question is not only about creating a training course in Moodle. It's about maintaining the health of the system within the institution, such as a University. Under the "health maintenance" means: availability and preservation of up-to-date documentation on system and manuals on Moodle separately for administrators, managers, teachers and students at their level, training consultants

  15. [Distant metastases of malignant tumors of head and neck].

    Science.gov (United States)

    Totan, C; Dincă, O; Negureanu, M; Vlădan, C; Bucur, Al

    2010-01-01

    The charts of 176 previously untreated patients with head and neck squamous cell carcinoma who completed treatment during 2006 in Oro-Maxillo-Facial Clinic, UMF "Carol Davila" Bucharest were reviewed. These patients had no evidence of distant metastases when initially evaluated. The overall incidence of distant metastases was 27.84%, varying from 10.52% for buccal mucosa to 63.63% for tongue and floor of the mouth (p < 0.05). 80% of the metastases were detected within two years after treatment. The rate also increased with the T and N classification; however, the N stage had greater influence on the rate of metastases than the T stage.

  16. Evidence for a Distant Giant Planet in the Solar System

    CERN Document Server

    Batygin, Konstantin

    2016-01-01

    Recent analyses have shown that distant orbits within the scattered disk population of the Kuiper belt exhibit an unexpected clustering in their respective arguments of perihelion. While several hypotheses have been put forward to explain this alignment, to date, a theoretical model that can successfully account for the observations remains elusive. In this work we show that the orbits of distant Kuiper belt objects cluster not only in argument of perihelion, but also in physical space. We demonstrate that the perihelion positions and orbital planes of the objects are tightly confined and that such a clustering has only a probability of 0.007% to be due to chance, thus requiring a dynamical origin. We find that the observed orbital alignment can be maintained by a distant eccentric planet with mass greater than ~10 Earth masses, whose orbit lies in approximately the same plane as those of the distant Kuiper belt objects, but whose perihelion is 180 degrees away from the perihelia of the minor bodies. In addit...

  17. Notes on the genus Pirdana Distant, 1886 (Lepidoptera: Hesperiidae)

    NARCIS (Netherlands)

    Jong, de R.; Treadaway, C.G.

    1993-01-01

    In the Oriental genus Pirdana Distant, 1886, the new species P. fusca is described from Samar (E Philippines). The phylogeny of the genus is discussed and as a consequence the endemic Sulawesi taxon P. hyela ismene (Felder & Felder, [1867]) is given back its species rank, bringing the total number o

  18. Radio Numbers of Certain m-Distant Trees

    Directory of Open Access Journals (Sweden)

    Srinivasa Rao Kola

    2014-01-01

    Full Text Available Radio coloring of a graph G with diameter d is an assignment f of positive integers to the vertices of G such that |f(u-f(v|≥1+d-d(u,v, where u and v are any two distinct vertices of G and d(u,v is the distance between u and v. The number max {f(u:u∈V(G} is called the span of f. The minimum of spans over all radio colorings of G is called radio number of G, denoted by rn(G. An m-distant tree T is a tree in which there is a path P of maximum length such that every vertex in V(T∖V(P is at the most distance m from P. This path P is called a central path. For every tree T, there is an integer m such that T is a m-distant tree. In this paper, we determine the radio number of some m-distant trees for any positive integer m≥2, and as a consequence of it, we find the radio number of a class of 1-distant trees (or caterpillars.

  19. Regional Distributions of Distant Metastases Detected in Differentiated Thyroid Cancers

    Directory of Open Access Journals (Sweden)

    Ebuzer Kalender

    2016-01-01

    Full Text Available Aim: The aim of our multicenter study is to determine retrospectively the regional distributions of distant metastases which are detected in differentiated thyroid cancers (DTC. Material and Method: Thirty-two of 960 patients with distant metastases who were given radioiodine (RAI treatment in Gaziantep University School of Medicine and Mustafa Kemal University School of Medicine were included to study. Six of patients were male, 26 of them were female. Mean age was 52±15.4. Hystopathological diagnoses were reported as papillary thyroid cancer in 23 patients and folliculary thyroid cancer in 9 patients. The distant metastasis ratio, metastasis regions and distributions were determined. Results: It was observed only lung metastasis in 18 (56.25 %, only bone metastasis in 6 (18.75 %, combination of lung and bone metastases in 3 (9.4 %, other organ metastases accompanying to bone and lung metastases in 3 (9.4 % (liver, soft tissue, mediastinum and multipl organ involvoment in 2 (6.2 % of patients. It was determined single metastasis region in 24 (75 %, 2 metastasis regions in 6 (18.75 % and multipl metastasis regions in 2 (6.25 % of patients. Discussion: Distant metastases are the biggest problem in treatment and follow-up of DTCs. It is very important to diagnosis of metastases and determine the regions of involvoment in these patients.

  20. Gas, dust, and star formation in distant radio galaxies

    NARCIS (Netherlands)

    Reuland, Michiel

    2005-01-01

    In this thesis I discuss recent observations of distant (z > 2) radio galaxies. There is strong evidence that radio galaxies are the progenitors of the brightest cluster ellipticals and are among the most luminous and massive galaxies at any epoch, allowing relatively detailed studies of their forma

  1. An Information Access Model at a Distant Branch Library

    Science.gov (United States)

    Stratton, John M.

    2004-01-01

    Academic branch libraries located at a distance from the parent institution often face unique challenges in meeting users' needs for scholarly information. This is especially true for distant branch libraries that do not have a specialized function or collection, but who often face the challenge of meeting users' needs for scholarly materials…

  2. Tree-level equivalence between a Lorentz-violating extension of QED and its dual model in electron-electron scattering

    Science.gov (United States)

    Toniolo, Giuliano R.; Fargnoli, H. G.; Brito, L. C. T.; Scarpelli, A. P. Baêta

    2017-02-01

    S-matrix amplitudes for the electron-electron scattering are calculated in order to verify the physical equivalence between two Lorentz-breaking dual models. We begin with an extended Quantum Electrodynamics which incorporates CPT-even Lorentz-violating kinetic and mass terms. Then, in a process of gauge embedding, its gauge-invariant dual model is obtained. The physical equivalence of the two models is established at tree level in the electron-electron scattering and the unpolarized cross section is calculated up to second order in the Lorentz-violating parameter.

  3. Tree-level equivalence between a Lorentz-violating extension of QED and its dual model in electron-electron scattering

    Energy Technology Data Exchange (ETDEWEB)

    Toniolo, Giuliano R.; Fargnoli, H.G.; Brito, L.C.T. [Universidade Federal de Lavras, Departamento de Fisica, Caixa Postal 3037, Lavras, Minas Gerais (Brazil); Scarpelli, A.P.B. [Setor Tecnico-Cientifico, Departamento de Policia Federal, Sao Paulo (Brazil)

    2017-02-15

    S-matrix amplitudes for the electron-electron scattering are calculated in order to verify the physical equivalence between two Lorentz-breaking dual models. We begin with an extended Quantum Electrodynamics which incorporates CPT-even Lorentz-violating kinetic and mass terms. Then, in a process of gauge embedding, its gauge-invariant dual model is obtained. The physical equivalence of the two models is established at tree level in the electron-electron scattering and the unpolarized cross section is calculated up to second order in the Lorentz-violating parameter. (orig.)

  4. Relative-locality distant observers and the phenomenology of momentum-space geometry

    CERN Document Server

    Amelino-Camelia, Giovanni; Kowalski-Glikman, Jerzy; Rosati, Giacomo; Trevisan, Gabriele

    2011-01-01

    We study the translational invariance of the relative-locality framework proposed in arXiv:1101.0931, which had been previously established only for the case of a single interaction. We provide an explicit example of boundary conditions at endpoints of worldlines, which indeed ensures the desired translational invariance for processes involving several interactions, even when some of the interactions are causally connected (particle exchange). We illustrate the properties of the associated relativistic description of distant observers within the example of a $\\kappa$-Poincar\\'e-inspired momentum-space geometry, with de Sitter metric and parallel transport governed by a non-metric and torsionful connection. We find that in such a theory simultaneously-emitted massless particles do not reach simultaneously a distant detector, as expected in light of the findings of arXiv:1103.5626 on the implications of non-metric connections. We also show that the theory admits a free-particle limit, where the relative-localit...

  5. Atypical modulation of distant functional connectivity by cognitive state in children with Autism Spectrum Disorders

    Directory of Open Access Journals (Sweden)

    Xiaozhen eYou

    2013-08-01

    Full Text Available We examined whether modulation of functional connectivity by cognitive state differed between pre-adolescent children with Autism Spectrum Disorders (ASD and age and IQ-matched control children. Children underwent functional magnetic resonance imaging (fMRI during two states, a resting state followed by a sustained attention task. A voxel-wise method was used to characterize functional connectivity at two levels, local (within a voxel’s 14 mm neighborhood and distant (outside of the voxel’s 14 mm neighborhood to the rest of the brain and regions exhibiting Group X State interaction were identified for both types of connectivity maps. Distant functional connectivity of regions in the left frontal lobe (dorsolateral [BA 11, 10]; supplementary motor area extending into dorsal anterior cingulate [BA 32/8]; and premotor [BA 6, 8, 9], right parietal lobe (paracentral lobule [BA 6 ]; angular gyrus [BA 39/40], and left posterior middle temporal cortex (BA 19/39 showed a Group X State interaction such that relative to the resting state, connectivity reduced (i.e., became focal in control children but increased (i.e., became diffuse in ASD children during the task state. Higher state-related increase in distant connectivity of left frontal and right angular gyrus predicted worse inattention in ASD children. Two graph theory measures (global efficiency and modularity were also sensitive to Group X State differences, with the magnitude of state-related change predicting inattention in the ASD children. Our results indicate that as ASD children transition from an unconstrained to a sustained attentional state, functional connectivity of frontal and parietal regions with the rest of the brain becomes more widespread in a manner that may be maladaptive as it was associated with attention problems in everyday life.

  6. Conformational changes of the histidine ATP-binding cassette transporter studied by double electron-electron resonance spectroscopy.

    Science.gov (United States)

    Sippach, Michael; Weidlich, Daniela; Klose, Daniel; Abé, Christoph; Klare, Johann; Schneider, Erwin; Steinhoff, Heinz-Jürgen

    2014-07-01

    The conformational dynamics of the histidine ABC transporter HisQMP2 from Salmonella enterica serovar Typhimurium, reconstituted into liposomes, is studied by site-directed spin labeling and double electron-electron resonance spectroscopy in the absence of nucleotides, in the ATP-bound, and in the post-hydrolysis state. The results show that the inter-dimer distances as measured between the Q-loops of HisP2 in the intact transporter resemble those determined for the maltose transporter in all three states of the hydrolysis cycle. Only in the presence of liganded HisJ the closed conformation of the nucleotide binding sites is achieved revealing the transmembrane communication of the presence of substrate. Two conformational states can be distinguished for the periplasmic moiety of HisQMP2 as detected by differences in distributions of interspin distances between positions 86 and 96 or 104 and 197. The observed conformational changes are correlated to proposed open, semi-open and closed conformations of the nucleotide binding domains HisP2. Our results are in line with a rearrangement of transmembrane helices 4 and 4' of HisQM during the closed to the semi-open transition of HisP2 driven by the reorientation of the coupled helices 3a and 3b to occur upon hydrolysis. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Probing the Structure of the Mechanosensitive Channel of Small Conductance in Lipid Bilayers with Pulsed Electron-Electron Double Resonance

    Science.gov (United States)

    Ward, Richard; Pliotas, Christos; Branigan, Emma; Hacker, Christian; Rasmussen, Akiko; Hagelueken, Gregor; Booth, Ian R.; Miller, Samantha; Lucocq, John; Naismith, James H.; Schiemann, Olav

    2014-01-01

    Mechanosensitive channel proteins are important safety valves against osmotic shock in bacteria, and are involved in sensing touch and sound waves in higher organisms. The mechanosensitive channel of small conductance (MscS) has been extensively studied. Pulsed electron-electron double resonance (PELDOR or DEER) of detergent-solubilized protein confirms that as seen in the crystal structure, the outer ring of transmembrane helices do not pack against the pore-forming helices, creating an apparent void. The relevance of this void to the functional form of MscS in the bilayer is the subject of debate. Here, we report PELDOR measurements of MscS reconstituted into two lipid bilayer systems: nanodiscs and bicelles. The distance measurements from multiple mutants derived from the PELDOR data are consistent with the detergent-solution arrangement of the protein. We conclude, therefore, that the relative positioning of the transmembrane helices is preserved in mimics of the cell bilayer, and that the apparent voids are not an artifact of detergent solution but a property of the protein that will have to be accounted for in any molecular mechanism of gating. PMID:24559986

  8. Site directed spin labelling and pulsed dipolar electron paramagnetic resonance (double electron-electron resonance) of force activation in muscle

    Energy Technology Data Exchange (ETDEWEB)

    Fajer, Piotr G [Institute of Molecular Biophysics, Department of Biological Science, National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310 (United States)

    2005-05-11

    The recent development of site specific spin labelling and advances in pulsed electron paramagnetic resonance(EPR) have established spin labelling as a viable structural biology technique. Specific protein sites or whole domains can be selectively targeted for spin labelling by cysteine mutagenesis. The secondary structure of the proteins is determined from the trends in EPR signals of labels attached to consecutive residues. Solvent accessibility or label mobility display periodicities along the labelled polypeptide chain that are characteristic of {beta}-strands (periodicity of 2 residues) or {alpha}-helices (3.6 residues). Low-resolution 3D structure of proteins is determined from the distance restraints. Two spin labels placed within 60-70 A of each other create a local dipolar field experienced by the other spin labels. The strength of this field is related to the interspin distance, {proportional_to} r{sup -3}. The dipolar field can be measured by the broadening of the EPR lines for the short distances (8-20 A) or for the longer distances (17-70 A) by the pulsed EPR methods, double electron-electron resonance(DEER) and double quantum coherence (DQC). A brief review of the methodology and its applications to the multisubunit muscle protein troponin is presented below.

  9. Results of Long-Duration Simulation of Distant Retrograde Orbits

    Directory of Open Access Journals (Sweden)

    Gary Turner

    2016-11-01

    Full Text Available Distant Retrograde Orbits in the Earth–Moon system are gaining in popularity as stable “parking” orbits for various conceptual missions. To investigate the stability of potential Distant Retrograde Orbits, simulations were executed, with propagation running over a thirty-year period. Initial conditions for the vehicle state were limited such that the position and velocity vectors were in the Earth–Moon orbital plane, with the velocity oriented such that it would produce retrograde motion about Moon. The resulting trajectories were investigated for stability in an environment that included the eccentric motion of Moon, non-spherical gravity of Earth and Moon, gravitational perturbations from Sun, Jupiter, and Venus, and the effects of radiation pressure. The results indicate that stability may be enhanced at certain resonant states within the Earth–Moon system.

  10. Distant galaxy clusters in the XMM Large Scale Structure survey

    CERN Document Server

    Willis, J P; Bremer, M N; Pierre, M; Adami, C; Ilbert, O; Maughan, B; Maurogordato, S; Pacaud, F; Valtchanov, I; Chiappetti, L; Thanjavur, K; Gwyn, S; Stanway, E R; Winkworth, C

    2012-01-01

    (Abridged) Distant galaxy clusters provide important tests of the growth of large scale structure in addition to highlighting the process of galaxy evolution in a consistently defined environment at large look back time. We present a sample of 22 distant (z>0.8) galaxy clusters and cluster candidates selected from the 9 deg2 footprint of the overlapping X-ray Multi Mirror (XMM) Large Scale Structure (LSS), CFHTLS Wide and Spitzer SWIRE surveys. Clusters are selected as extended X-ray sources with an accompanying overdensity of galaxies displaying optical to mid-infrared photometry consistent with z>0.8. Nine clusters have confirmed spectroscopic redshifts in the interval 0.80.8 clusters.

  11. Synchronization scenario of two distant mutually coupled semiconductor lasers

    DEFF Research Database (Denmark)

    Mulet, Josep; Mirasso, Claudio; Heil, Tilmann;

    2004-01-01

    We present numerical and experimental investigations of the synchronization of the coupling-induced instabilities in two distant mutually coupled semiconductor lasers. In our experiments, two similar Fabry-Perot lasers are coupled via their coherent optical fields. Our theoretical framework...... is based on a rate equation model obtained under weak coupling conditions. In both experiments and simulations, we find (achronal) synchronization of subnanosecond intensity fluctuations in concurrence with asymmetric physical roles between the lasers, even under symmetric operating conditions. We explore...

  12. Distant and wide range wireless power transfer from metamedia

    Science.gov (United States)

    Zhu, Lin; Luo, Xudong; Ma, Hongru

    2016-07-01

    Based on electromagnetic scattering theory, a model of superscatterer enhanced distant wireless power transfer (WPT) device has designed and analyzed with the concept of transformation optics. The numerical results obtained through a series expansion method reveal that a properly designed ss-WPT has high efficiency for long transfer distances as well as a wide transfer range. The transfer distance can be further enlarged by fine tuning of the design. These effects can be explained qualitatively through the study of magnetic flux.

  13. Learning for Microblogs with Distant Supervision: Political Forecasting with Twitter

    Science.gov (United States)

    2012-04-01

    often classified as both positive and negative by a lexi - con (Section 5.1). This could explain the behav- ior seen in Figure 3 in which both the positive...Correlation results are shown in Table 4. This baseline parallels the results seen when topic identification is used: the sentiment lexi - con is again...negative lexi - con words. The OpinionFinder lexicon failed to correlate (inversely) with Gallup’s Approval polls, whereas a distantly trained classifier

  14. Non-Perturbative Entangling Gates between Distant Qubits using Uniform Cold Atom Chains

    CERN Document Server

    Banchi, Leonardo; Verrucchi, Paola; Bose, Sougato

    2010-01-01

    We propose a new fast scalable method for achieving a two-qubit entangling quantum gate between arbitrary distant qubits in a network by exploiting dispersionless propagation in uniform chains. This is achieved dynamically by switching on a strong interaction between the qubits and a bus formed by a non-engineered chain of interacting qubits. The quality of the gate scales very efficiently with qubit separations. Surprisingly, a sudden switching of the coupling is not necessary and our gate mechanism is not altered by a possibly gradual switching. The bus is also naturally reset to its initial state making the complex resetting procedure unnecessary after each application of the gate. Moreover, we propose a possible experimental realization in cold atoms trapped in optical lattices and near field Fresnel trapping potentials, which are both accessible to current technology.

  15. Conformational cycle of the vitamin B12 ABC importer in liposomes detected by double electron-electron resonance (DEER).

    Science.gov (United States)

    Joseph, Benesh; Korkhov, Vladimir M; Yulikov, Maxim; Jeschke, Gunnar; Bordignon, Enrica

    2014-02-01

    Double electron-electron resonance is used here to investigate intermediates of the transport cycle of the Escherichia coli vitamin B12 ATP-binding cassette importer BtuCD-F. Previously, we showed the ATP-induced opening of the cytoplasmic gate I in TM5 helices, later confirmed by the AMP-PNP-bound BtuCD-F crystal structure. Here, other key residues are analyzed in TM10 helices (positions 307 and 322) and in the cytoplasmic gate II, i.e. the loop between TM2 and TM3 (positions 82 and 85). Without BtuF, binding of ATP induces detectable changes at positions 307 and 85 in BtuCD in liposomes. Together with BtuF, ATP triggers the closure of the cytoplasmic gate II in liposomes (reported by both positions 82 and 85). This forms a sealed cavity in the translocation channel in agreement with the AMP-PNP·BtuCD-F x-ray structure. When vitamin B12 and AMP-PNP are simultaneously present, the extent of complex formation is reduced, but the short 82-82 interspin distance detected indicates that the substrate does not affect the closed conformation of this gate. The existence of the BtuCD-F complex under these conditions is verified with spectroscopically orthogonal nitroxide and Gd(III)-based labels. The cytoplasmic gate II remains closed also in the vanadate-trapped state, but it reopens in the ADP-bound state of the complex. Therefore, we suggest that the substrate likely trapped in ATP·BtuCD-F can be released after ATP hydrolysis but before the occluded ADP-bound conformation is reached.

  16. Two-dimensional electron-electron double resonance and electron spin-echo study of solute dynamics in smectics

    Science.gov (United States)

    Gorcester, Jeff; Rananavare, Shankar B.; Freed, Jack H.

    1989-05-01

    Electron spin-echo (ESE) and two-dimensional electron-electron double resonance (2D ELDOR) experiments have been performed as a function of director orientation and temperature in the smectic A phase of the liquid crystal S2 for the spin-probe PD-tempone(2×10-3 M). Over the entire temperature range studied (288-323 K) we observe significant 2D ELDOR cross peaks only for ΔMI =±1 indicative of 14N spin-relaxation and negligible Heisenberg exchange. From the angular dependent 14N spin-relaxation rates we obtain the dipolar spectral densities at the hyperfine (hf) frequency, whereas from a combination of ESE and 2D ELDOR we obtain the dipolar and Zeeman-dipolar spectral densities at zero frequency. The angular dependent spectral densities were successfully decomposed into their basic components in accordance with theory. The angular dependent spectral densities at the hf frequency are not predicted by a model of anisotropic rotational diffusion in a nematic orienting potential, but are consistent with predictions of a model due to Moro and Nordio of solute rototranslational diffusion in a McMillan-type potential. The angular dependence also indicates that order director fluctuations in the smectic phase are suppressed at frequencies on the order of 10 MHz. An additional contribution to solute reorientation due to cooperative hydrocarbon chain fluctuations is suggested to account for the behavior of the observed spectral densities at zero frequency. An evaluation of the relevance of several other dynamical models to this experimental work is also presented.

  17. INTERACT

    DEFF Research Database (Denmark)

    Jochum, Elizabeth; Borggreen, Gunhild; Murphey, TD

    This paper considers the impact of visual art and performance on robotics and human-computer interaction and outlines a research project that combines puppetry and live performance with robotics. Kinesics—communication through movement—is the foundation of many theatre and performance traditions...... interaction between a human operator and an artificial actor or agent. We can apply insights from puppetry to develop culturally-aware robots. Here we describe the development of a robotic marionette theatre wherein robotic controllers assume the role of human puppeteers. The system has been built, tested...

  18. 76 FR 3646 - Safety Requirements and Manning Exemption Eligibility on Distant Water Tuna Fleet Vessels

    Science.gov (United States)

    2011-01-20

    ... SECURITY Coast Guard Safety Requirements and Manning Exemption Eligibility on Distant Water Tuna Fleet... Requirements and Manning Exemption Eligibility on Distant Water Tuna Fleet Vessels. All comments received will... availability of a draft policy regarding distant water tuna fleet vessels manning exemption eligibility...

  19. Inference of distant genetic relations in humans using "1000 genomes".

    Science.gov (United States)

    Al-Khudhair, Ahmed; Qiu, Shuhao; Wyse, Meghan; Chowdhury, Shilpi; Cheng, Xi; Bekbolsynov, Dulat; Saha-Mandal, Arnab; Dutta, Rajib; Fedorova, Larisa; Fedorov, Alexei

    2015-01-07

    Nucleotide sequence differences on the whole-genome scale have been computed for 1,092 people from 14 populations publicly available by the 1000 Genomes Project. Total number of differences in genetic variants between 96,464 human pairs has been calculated. The distributions of these differences for individuals within European, Asian, or African origin were characterized by narrow unimodal peaks with mean values of 3.8, 3.5, and 5.1 million, respectively, and standard deviations of 0.1-0.03 million. The total numbers of genomic differences between pairs of all known relatives were found to be significantly lower than their respective population means and in reverse proportion to the distance of their consanguinity. By counting the total number of genomic differences it is possible to infer familial relations for people that share down to 6% of common loci identical-by-descent. Detection of familial relations can be radically improved when only very rare genetic variants are taken into account. Counting of total number of shared very rare single nucleotide polymorphisms (SNPs) from whole-genome sequences allows establishing distant familial relations for persons with eighth and ninth degrees of relationship. Using this analysis we predicted 271 distant familial pairwise relations among 1,092 individuals that have not been declared by 1000 Genomes Project. Particularly, among 89 British and 97 Chinese individuals we found three British-Chinese pairs with distant genetic relationships. Individuals from these pairs share identical-by-descent DNA fragments that represent 0.001%, 0.004%, and 0.01% of their genomes. With affordable whole-genome sequencing techniques, very rare SNPs should become important genetic markers for familial relationships and population stratification. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  20. "Spooky actions at a distance": physics, psi, and distant healing.

    Science.gov (United States)

    Leder, Drew

    2005-10-01

    Over decades, consciousness research has accumulated evidence of the real and measureable existence of "spooky actions at a distance"--modes of telepathy, telekinesis, clairvoyance, and the like. More recently scientists have begun rigorous study of the effects of distant healing intention and prayer vis-a-vis nonhuman living systems and patients in clinical trials. A barrier to taking such work seriously may be the belief that it is fundamentally incompatible with the scientific world view. This article suggests that it need not be; contemporary physics has generated a series of paradigms that can be used to make sense of, interpret, and explore "psi" and distant healing. Four such models are discussed, two drawn from relativity theory and two from quantum mechanics. First is the energetic transmission model, presuming the effects of conscious intention to be mediated by an as-yet unknown energy signal. Second is the model of path facilitation. As gravity, according to general relativity, "warps" space-time, easing certain pathways of movement, so may acts of consciousness have warping and facilitating effects on the fabric of the surrounding world. Third is the model of nonlocal entanglement drawn from quantum mechanics. Perhaps people, like particles, can become entangled so they behave as one system with instantaneous and unmediated correlations across a distance. Last discussed is a model involving actualization of potentials. The act of measurement in quantum mechanics collapses a probabilistic wave function into a single outcome. Perhaps conscious healing intention can act similarly, helping to actualize one of a series of possibilities; for example, recovery from a potentially lethal tumor. Such physics-based models are not presented as explanatory but rather as suggestive. Disjunctions as well as compatibilities between the phenomena of modern physics and those of psi and distant healing are explored.

  1. A Good Hard Look at Growing Supermassive Black Holes in the Distant Universe

    Science.gov (United States)

    Brandt, W. Niel; Chandra Deep Fields Team

    2017-01-01

    Sensitive cosmic X-ray surveys with the Chandra, XMM-Newton, and now NuSTAR observatories have revolutionized our ability to find and study distant active galactic nuclei (AGNs), the main sites of supermassive black hole growth in the Universe. I will describe some of the resulting discoveries about the demographics, physics, and ecology of distant AGNs with an emphasis on the deepest Chandra surveys, the Chandra Deep Fields. Some specific topics covered will include (1) robust X-ray spectral and variability characterization of the AGNs producing most of cosmic accretion power; (2) the demographics of AGNs in the first galaxies as revealed by direct detection and stacking; (3) AGN/galaxy interactions as investigated via the host properties of X-ray AGNs; and (4) the cosmic balance of power between supermassive black holes and stars. I will also briefly describe other remarkable discoveries coming from the deepest X-ray surveys; e.g., measurements of the evolving X-ray binary populations of normal and starburst galaxies. I will end by discussing some key outstanding questions and new observations and missions aiming to answer them.

  2. Magnetic configuration of the distant plasma sheet - ISEE 3 observations

    Science.gov (United States)

    Slavin, J. A.; Smith, E. J.; Daly, P. W.; Sanderson, T. R.; Wenzel, K.-P.; Lepping, R. P.

    1987-01-01

    The influence of the IMF orientation and magnitude and substorm activity on the magnetic configuration of the central plasma sheet at 20-240 earth radii down the geomagnetic tail is investigated on the basis of ISEE-3 data. The results are presented graphically, and high-speed antisolar bulk flows threaded by southward magnetic fields are shown to be present in the distant plasma sheet after periods of substorm activity and southward IMF Bz. The effective dayside reconnection efficiency is estimated as 25 + or - 4 percent, in good agreement with theoretical models.

  3. Cancer Salivary Biomarkers for Tumours Distant to the Oral Cavity

    Directory of Open Access Journals (Sweden)

    Óscar Rapado-González

    2016-09-01

    Full Text Available The analysis of saliva as a diagnostic approach for systemic diseases was proposed just two decades ago, but recently great interest in the field has emerged because of its revolutionary potential as a liquid biopsy and its usefulness as a non-invasive sampling method. Multiple molecules isolated in saliva have been proposed as cancer biomarkers for diagnosis, prognosis, drug monitoring and pharmacogenetic studies. In this review, we focus on the current status of the salivary diagnostic biomarkers for different cancers distant to the oral cavity, noting their potential use in the clinic and their applicability in personalising cancer therapies.

  4. Interactions

    DEFF Research Database (Denmark)

    The main theme of this anthology is the unique interaction between mathematics, physics and philosophy during the beginning of the 20th century. Seminal theories of modern physics and new fundamental mathematical structures were discovered or formed in this period. Significant physicists...... such as Lorentz and Einstein as well as mathematicians such as Poincare, Minkowski, Hilbert and Weyl contributed to this development. They created the new physical theories and the mathematical disciplines that play such paramount roles in their mathematical formulations. These physicists and mathematicians were...

  5. Nearby Hot Stars May Change Our View of Distant Sources

    Science.gov (United States)

    Kohler, Susanna

    2017-07-01

    As if it werent enough that quasars distant and bright nuclei of galaxies twinkle of their own accord due to internal processes, nature also provides another complication: these distant radio sources can also appear to twinkle because of intervening material between them and us. A new study has identified a possible source for the material getting in the way.Unexplained VariabilityA Spitzer infrared view of the Helix nebula, which contains ionized streamers of gas extending radially outward from the central star. [NASA/JPL-Caltech/Univ. of Ariz.]Distant quasars occasionally display extreme scintillation, twinkling with variability timescales shorter than a day. This intra-day variability is much greater than we can account for with standard models of the interstellar medium lying between the quasar and us. So what could cause this extreme scattering instead?The first clue to this mystery came from the discovery of strong variability in the radio source PKS 1322110. In setting up follow-up observations of this object, Mark Walker (Manly Astrophysics, Australia) and collaborators noticed that, in the plane of the sky, PKS 1322110 lies very near the bright star Spica. Could this be coincidence, or might this bright foreground star have something to do with the extreme scattering observed?Diagram explaining the source of the intra-day radio source variability as intervening filaments surrounding a hot star. [M. Walker/CSIRO/Manly Astrophysics]Swarms of ClumpsWalker and collaborators put forward a hypothesis: perhaps the ultraviolet photons of nearby hot stars ionize plasma around them, which in turn causes the extreme scattering of the distant background sources.As a model, the authors consider the Helix Nebula, in which a hot, evolved star is surrounded by cool globules of molecular hydrogen gas. The radiation from the star hits these molecular clumps, dragging them into long radial streamers and ionizing their outer skins.Though the molecular clumps in the Helix

  6. On the structure of the distant magnetotail - ISEE 3

    Science.gov (United States)

    Fairfield, D. H.

    1992-01-01

    The relative frequency of observation of the magnetosheath and magnetotail in the region where a nominal magnetotail is expected is determined on the basis of ISEE-3 magnetic field and electron plasma data. These observations are compared with how frequently a tail of a given radius would be expected to be seen, assuming typical variations in the direction of the solar wind flow relative to the radial. Observations match expectations if the average radius consistent with an open magnetotail where field lines are lost both through the magnetopause and also by closing along the equatorial current sheet. This relatively small radius is consistent with an open magnetotail where field lines are lost both through the magnetopause and also by closing across the equatorial current sheet. The average solar magnetospheric Bz component of the field in the distant plasma sheet is 0.6 nT during quiet times but zero during disturbed times, which suggests that when the polar cap becomes smaller during quiet times, many of the field lines that previously formed the distant tail lobes are converted into closed field lines that cross the equatorial plane earthward of 240 RE.

  7. Plasma electrons as tracers of distant magnetotail structure - ISEE-3

    Science.gov (United States)

    Baker, D. N.; Bame, S. J.; Gosling, J. T.; Gussenhoven, M. S.

    1988-01-01

    This paper compares the electron spectra and phase space densities measured concurrently by ISEE-3 at 200 R(E), with those measured by DMSP at low altitudes. The field-aligned lobe electron phase space densities above 200 eV at ISEE were found to agree well with the DMSP-measured polar rain phase space densities near the polar cap; the spectral slopes above 200 eV were also similar. Below 100-200 eV, a thermal electron population was measured by ISEE in the distant tail, which arose from local entry of plasma through the distant magnetopause, which is not present at DMSP altitudes. These data show that the suprathermal tail lobe electrons are essentially a test particle population which can move freely along field lines to form polar rain; in contrast, the thermal electrons are bound to the tailward-flowing lobe ion population far down the tail and, thus, cannot reach the polar cap regions.

  8. Skipping Posterior Dynamic Transpedicular Stabilization for Distant Segment Degenerative Disease

    Directory of Open Access Journals (Sweden)

    Bilgehan Solmaz

    2012-01-01

    Full Text Available Objective. To date, there is still no consensus on the treatment of spinal degenerative disease. Current surgical techniques to manage painful spinal disorders are imperfect. In this paper, we aimed to evaluate the prospective results of posterior transpedicular dynamic stabilization, a novel surgical approach that skips the segments that do not produce pain. This technique has been proven biomechanically and radiologically in spinal degenerative diseases. Methods. A prospective study of 18 patients averaging 54.94 years of age with distant spinal segment degenerative disease. Indications consisted of degenerative disc disease (57%, herniated nucleus pulposus (50%, spinal stenosis (14.28%, degenerative spondylolisthesis (14.28%, and foraminal stenosis (7.1%. The Oswestry Low-Back Pain Disability Questionnaire and visual analog scale (VAS for pain were recorded preoperatively and at the third and twelfth postoperative months. Results. Both the Oswestry and VAS scores showed significant improvement postoperatively (P<0.05. We observed complications in one patient who had spinal epidural hematoma. Conclusion. We recommend skipping posterior transpedicular dynamic stabilization for surgical treatment of distant segment spinal degenerative disease.

  9. Distant ionospheric photoelectron energy peak observations at Venus

    Science.gov (United States)

    Coates, A. J.; Wellbrock, A.; Frahm, R. A.; Winningham, J. D.; Fedorov, A.; Barabash, S.; Lundin, R.

    2015-08-01

    The dayside of the Venus ionosphere at the top of the planet's thick atmosphere is sustained by photoionization. The consequent photoelectrons may be identified by specific peaks in the energy spectrum at 20-30 eV which are mainly due to atomic oxygen photoionization. The ASPERA-4 electron spectrometer has an energy resolution designed to identify the photoelectron production features. Photoelectrons are seen not only in their production region, the sunlit ionosphere, but also at more distant locations on the nightside of the Venus environment. Here, we present a summary of the work to date on observations of photoelectrons at Venus, and their comparison with similar processes at Titan and Mars. We expand further by presenting new examples of the distant photoelectrons measured at Venus in the dark tail and further away from Venus than seen before. The photoelectron and simultaneous ion data are then used to determine the ion escape rate from Venus for one of these intervals. We compare the observed escape rates with other rates measured at Venus, and at other planets, moons and comets. We find that the escape rates are grouped by object type when plotted against body radius.

  10. Resolved stellar population of distant galaxies in the ELT era

    CERN Document Server

    Greggio, L; Zaggia, S; Fantinel, D; Uslenghi, M

    2012-01-01

    The expected imaging capabilities of future Extremely Large Telescopes (ELTs) will offer the unique possibility to investigate the stellar population of distant galaxies from the photometry of the stars in very crowded fields. Using simulated images and photometric analysis we explore here two representative science cases aimed at recovering the characteristics of the stellar populations in the inner regions of distant galaxies. Specifically: case A) at the center of the disk of a giant spiral in the Centaurus Group, (mu B~21, distance of 4.6 Mpc); and, case B) at half of the effective radius of a giant elliptical in the Virgo Cluster (mu~19.5, distance of 18 Mpc). We generate synthetic frames by distributing model stellar populations and adopting a representative instrumental set up, i.e. a 42 m Telescope operating close to the diffraction limit. The effect of crowding is discussed in detail showing how stars are measured preferentially brighter than they are as the confusion limit is approached. We find tha...

  11. Distantly Labeling Data for Large Scale Cross-Document Coreference

    CERN Document Server

    Singh, Sameer; McCallum, Andrew

    2010-01-01

    Cross-document coreference, the problem of resolving entity mentions across multi-document collections, is crucial to automated knowledge base construction and data mining tasks. However, the scarcity of large labeled data sets has hindered supervised machine learning research for this task. In this paper we develop and demonstrate an approach based on ``distantly-labeling'' a data set from which we can train a discriminative cross-document coreference model. In particular we build a dataset of more than a million people mentions extracted from 3.5 years of New York Times articles, leverage Wikipedia for distant labeling with a generative model (and measure the reliability of such labeling); then we train and evaluate a conditional random field coreference model that has factors on cross-document entities as well as mention-pairs. This coreference model obtains high accuracy in resolving mentions and entities that are not present in the training data, indicating applicability to non-Wikipedia data. Given the ...

  12. Abstract Mindsets Increase Believability of Spatially Distant Online Messages

    Directory of Open Access Journals (Sweden)

    Hande Sungur

    2016-07-01

    Full Text Available Growing evidence from online credibility research reveals that online users rely on heuristic processes to evaluate the credibility of online information. The current paper, which is based on the construal level theory, proposes that congruency between the psychological distance of a stimulus and the way it is mentally construed can act as a heuristic for believability. According to construal level theory, psychologically close (e.g., spatially, temporally, socially stimuli are represented concretely whereas psychologically distant stimuli are represented abstractly. The level of mental construals and the psychological distance of information have been shown to influence people’s truth judgments in offline contexts. This study tests whether congruency between the construal level of people’s mindsets (abstract vs. concrete and the psychological distance implied in an online message (far vs. close enhances message believability. By partially confirming construal level theory predictions, we found that believability of an online news item about a distant location increased when people maintained an abstract mindset rather than a concrete one. The effect of a concrete mindset on believability was not significant for the close psychological distance condition. Our findings provide initial evidence that congruency between the construal level of people’s mindsets and psychological distance cues in online messages can act as a heuristic for believability. We discuss the potential of applying the construal level theory framework to the growing literature on online cognitive heuristics in the area of online information credibility.

  13. Sensitivity of Saturn's orbit to a hypothetical distant planet

    Science.gov (United States)

    Folkner, William; Jacobson, Robert A.; Park, Ryan; Williams, James G.

    2016-10-01

    Several distant scattered Kuiper belt objects have similar perihelion directions that might be aligned due to the influence an unknown planet well outside the orbit of Neptune (Batygin & Brown, 2016 Astronomical J. 151:22). Such a planet, with a mass up to an order of magnitude larger than the Earth, would affect the rest of the solar system. Saturn, which is well observed from radio range and VLBI observations of the Cassini spacecraft, provides an opportunity to look for these perturbations. An unknown large planet would be expected to affect the orbit of Saturn, but the effect might be partially absorbed in the estimation of parameters used to fit the planetary ephemerides. Ephemeris parameters include the planetary orbital elements, the mass of the Sun and the masses of asteroids that perturb the orbit of Mars. Earlier analysis of the Cassini data showed no effect as suggested by the Modified Newtonian Dynamics theory (Hees et al., 2014 Phys. Rev. D 89:102002). We present an updated Cassini data set, with the accuracy of ranges to Saturn improved through updated estimates of the Cassini spacecraft orbit, and an analysis of the largest possible perturbing distant planet mass consistent with the ranging data.

  14. PADRE: Pedigree-Aware Distant-Relationship Estimation.

    Science.gov (United States)

    Staples, Jeffrey; Witherspoon, David J; Jorde, Lynn B; Nickerson, Deborah A; Below, Jennifer E; Huff, Chad D

    2016-07-07

    Accurate estimation of shared ancestry is an important component of many genetic studies; current prediction tools accurately estimate pairwise genetic relationships up to the ninth degree. Pedigree-aware distant-relationship estimation (PADRE) combines relationship likelihoods generated by estimation of recent shared ancestry (ERSA) with likelihoods from family networks reconstructed by pedigree reconstruction and identification of a maximum unrelated set (PRIMUS), improving the power to detect distant relationships between pedigrees. Using PADRE, we estimated relationships from simulated pedigrees and three extended pedigrees, correctly predicting 20% more fourth- through ninth-degree simulated relationships than when using ERSA alone. By leveraging pedigree information, PADRE can even identify genealogical relationships between individuals who are genetically unrelated. For example, although 95% of 13(th)-degree relatives are genetically unrelated, in simulations, PADRE correctly predicted 50% of 13(th)-degree relationships to within one degree of relatedness. The improvement in prediction accuracy was consistent between simulated and actual pedigrees. We also applied PADRE to the HapMap3 CEU samples and report new cryptic relationships and validation of previously described relationships between families. PADRE greatly expands the range of relationships that can be estimated by using genetic data in pedigrees. Copyright © 2016 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  15. Extragalactic Jets as Probes of Distant Clusters of Galaxies and the Clusters Occupied by Bent Radio AGN (COBRA) Survey

    CERN Document Server

    Blanton, Elizabeth L; Wing, Joshua D; Ashby, M L N; Golden-Marx, Emmet; Brodwin, Mark; Douglass, E M; Randall, Scott W; Clarke, T E

    2014-01-01

    We are conducting a large survey of distant clusters of galaxies using radio sources with bent jets and lobes as tracers. These radio sources are driven by AGN and achieve their bent morphologies through interaction with the surrounding gas found in clusters of galaxies. Based on low-redshift studies, these types of sources can be used to identify clusters very efficiently. We present initial results from our survey of 653 bent-double radio sources with optical hosts too faint to appear in the SDSS. The sample was observed in the infrared with Spitzer, and it has revealed $\\sim$200 distant clusters or proto-clusters in the redshift range $z\\sim0.7 - 3.0$. The sample of bent-doubles contains both quasars and radio galaxies enabling us to study both radiative and kinetic mode feedback in cluster and group environments at a wide range of redshifts.

  16. The baryon content of distant X-ray Galaxy Clusters

    Science.gov (United States)

    Santos, Joana

    In the framework of the current cosmological paradigm, cosmic evolution is mostly driven by gravity through the hierarchical growth of cold dark matter structures. However, the evolution of the directly observed luminous component involves complex non-gravitational processes such as cooling, star formation and feedback mechanisms involving the conventional matter well known to us, termed shortly as baryons. Clusters of galaxies are the largest virialized systems in the Universe, hence are ideal laboratories to study the evolution of baryons. The baryon content of clusters accounts for roughly 15% of their total mass, encompassing a "cold phase" in the form of luminous galaxy masses, and a "hot phase" corresponding to the X-ray emitting intracluster medium (ICM). The thermodynamics of baryons is affected by non-trivial phenomena and the interplay of the intricate processes between these two phases remains, to a large extent, unclear. In this thesis I investigate the properties of both the ICM and the underlying galaxy populations in X-ray selected distant clusters, with the aim of constraining physical processes governing the evolution of clusters and their galaxies. The inner regions of local clusters often exhibit radiative cooling, termed cool cores (CC). I have made an important step in investigating the abundance of cool cores in the distant cluster population, by devising efficient methods to characterize local CCs, that were applied to the highest redshift cluster sample currently available (0.7 1) clusters are hard to find. The XMM-Newton Distant Cluster Project (XDCP) is a survey aimed to construct a complete sample of z ˜-1 clusters from the XMM-Newton archive. Within this scope a large effort has been done to confirm potential distant cluster candidates by exploring a new optical & near-infrared imaging technique to identify overdensities of galaxies. Twenty-two cluster candidates were imaged during two runs at the ESO/La Silla Observatory, of which

  17. A peculiar HI cloud near the distant globular cluster Pal 4

    CERN Document Server

    van Loon, Jacco Th; Putman, Mary; Peek, Joshua E G; Gibson, Steven J; Douglas, Kevin A; Korpela, Eric J

    2009-01-01

    We present 21-cm observations of four Galactic globular clusters, as part of the on-going GALFA-HI Survey at Arecibo. We discovered a peculiar HI cloud in the vicinity of the distant (109 kpc) cluster Pal 4, and discuss its properties and likelihood of association with the cluster. We conclude that an association of the HI cloud and Pal 4 is possible, but that a chance coincidence between Pal 4 and a nearby compact high-velocity cloud cannot be ruled out altogether. New, more stringent upper limits were derived for the other three clusters: M 3, NGC 5466, and Pal 13. We briefly discuss the fate of globular cluster gas and the interaction of compact clouds with the Galactic Halo gas.

  18. Distant, delayed and ancient earthquake-induced landslides

    Science.gov (United States)

    Havenith, Hans-Balder; Torgoev, Almaz; Braun, Anika; Schlögel, Romy; Micu, Mihai

    2016-04-01

    On the basis of a new classification of seismically induced landslides we outline particular effects related to the delayed and distant triggering of landslides. Those cannot be predicted by state-of-the-art methods. First, for about a dozen events the 'predicted' extension of the affected area is clearly underestimated. The most problematic cases are those for which far-distant triggering of landslides had been reported, such as for the 1988 Saguenay earthquake. In Central Asia reports for such cases are known for areas marked by a thick cover of loess. One possible contributing effect could be a low-frequency resonance of the thick soils induced by distant earthquakes, especially those in the Pamir - Hindu Kush seismic region. Such deep focal and high magnitude (>>7) earthquakes are also found in Europe, first of all in the Vrancea region (Romania). For this area and others in Central Asia we computed landslide event sizes related to scenario earthquakes with M>7.5. The second particular and challenging type of triggering is the one delayed with respect to the main earthquake event: case histories have been reported for the Racha earthquake in 1991 when several larger landslides only started moving 2 or 3 days after the main shock. Similar observations were also made after other earthquake events in the U.S., such as after the 1906 San Francisco, the 1949 Tacoma, the 1959 Hebgen Lake and the 1983 Bora Peak earthquakes. Here, we will present a series of detailed examples of (partly monitored) mass movements in Central Asia that mainly developed after earthquakes, some even several weeks after the main shock: e.g. the Tektonik and Kainama landslides triggered in 1992 and 2004, respectively. We believe that the development of the massive failures is a consequence of the opening of tension cracks during the seismic shaking and their filling up with water during precipitations that followed the earthquakes. The third particular aspect analysed here is the use of large

  19. Focus: Two-dimensional electron-electron double resonance and molecular motions: The challenge of higher frequencies

    Science.gov (United States)

    Franck, John M.; Chandrasekaran, Siddarth; Dzikovski, Boris; Dunnam, Curt R.; Freed, Jack H.

    2015-06-01

    The development, applications, and current challenges of the pulsed ESR technique of two-dimensional Electron-Electron Double Resonance (2D ELDOR) are described. This is a three-pulse technique akin to 2D Exchange Nuclear Magnetic Resonance, but involving electron spins, usually in the form of spin-probes or spin-labels. As a result, it required the extension to much higher frequencies, i.e., microwaves, and much faster time scales, with π/2 pulses in the 2-3 ns range. It has proven very useful for studying molecular dynamics in complex fluids, and spectral results can be explained by fitting theoretical models (also described) that provide a detailed analysis of the molecular dynamics and structure. We discuss concepts that also appear in other forms of 2D spectroscopy but emphasize the unique advantages and difficulties that are intrinsic to ESR. Advantages include the ability to tune the resonance frequency, in order to probe different motional ranges, while challenges include the high ratio of the detection dead time vs. the relaxation times. We review several important 2D ELDOR studies of molecular dynamics. (1) The results from a spin probe dissolved in a liquid crystal are followed throughout the isotropic → nematic → liquid-like smectic → solid-like smectic → crystalline phases as the temperature is reduced and are interpreted in terms of the slowly relaxing local structure model. Here, the labeled molecule is undergoing overall motion in the macroscopically aligned sample, as well as responding to local site fluctuations. (2) Several examples involving model phospholipid membranes are provided, including the dynamic structural characterization of the boundary lipid that coats a transmembrane peptide dimer. Additionally, subtle differences can be elicited for the phospholipid membrane phases: liquid disordered, liquid ordered, and gel, and the subtle effects upon the membrane, of antigen cross-linking of receptors on the surface of plasma membrane

  20. Focus: Two-dimensional electron-electron double resonance and molecular motions: The challenge of higher frequencies

    Energy Technology Data Exchange (ETDEWEB)

    Franck, John M.; Chandrasekaran, Siddarth; Dzikovski, Boris; Dunnam, Curt R.; Freed, Jack H., E-mail: jhf3@cornell.edu [Department of Chemistry and Chemical Biology and National Biomedical Center for Advanced ESR Technology, Cornell University, Ithaca, New York 14853 (United States)

    2015-06-07

    The development, applications, and current challenges of the pulsed ESR technique of two-dimensional Electron-Electron Double Resonance (2D ELDOR) are described. This is a three-pulse technique akin to 2D Exchange Nuclear Magnetic Resonance, but involving electron spins, usually in the form of spin-probes or spin-labels. As a result, it required the extension to much higher frequencies, i.e., microwaves, and much faster time scales, with π/2 pulses in the 2-3 ns range. It has proven very useful for studying molecular dynamics in complex fluids, and spectral results can be explained by fitting theoretical models (also described) that provide a detailed analysis of the molecular dynamics and structure. We discuss concepts that also appear in other forms of 2D spectroscopy but emphasize the unique advantages and difficulties that are intrinsic to ESR. Advantages include the ability to tune the resonance frequency, in order to probe different motional ranges, while challenges include the high ratio of the detection dead time vs. the relaxation times. We review several important 2D ELDOR studies of molecular dynamics. (1) The results from a spin probe dissolved in a liquid crystal are followed throughout the isotropic → nematic → liquid-like smectic → solid-like smectic → crystalline phases as the temperature is reduced and are interpreted in terms of the slowly relaxing local structure model. Here, the labeled molecule is undergoing overall motion in the macroscopically aligned sample, as well as responding to local site fluctuations. (2) Several examples involving model phospholipid membranes are provided, including the dynamic structural characterization of the boundary lipid that coats a transmembrane peptide dimer. Additionally, subtle differences can be elicited for the phospholipid membrane phases: liquid disordered, liquid ordered, and gel, and the subtle effects upon the membrane, of antigen cross-linking of receptors on the surface of plasma membrane

  1. CGCG 480-022: A distant lonesome merger?

    CERN Document Server

    Carretero, C; Gonzalez-Garcia, C; Beckman, J E; Quilis, V

    2006-01-01

    We present a complete analysis, which includes morphology, kinematics, stellar populations and N-body simulations of CGCG 480-022, the most distant (cz=14317 km/s) isolated galaxy studied so far in such detail. The results all support the hypothesis that this galaxy has suffered a major merger event with a companion of ~0.1 times its mass. Morphology reveals the presence of a circumnuclear ring and possibly further ring debris. The radial velocity curve looks symmetrical, whilst the velocity dispersion increases with radius reaching values that do not correspond to a virialized system. Moreover, this galaxy deviates significantly from the Fundamental Plane and the Faber-Jackson relation. The stellar population analysis show that the ring is younger and more metal-rich, which suggest that it has undergone a fairly recent burst of star formation. Both morphological and dynamical results are in broad agreeement with our N-body simulations.

  2. Transplantes cardiopulmonar e pulmonar com doador em localidade distante

    OpenAIRE

    Fragomeni,Luis Sérgio; Bonser,Robert S; Kaye,Michael P; Stuart W Jamieson

    1988-01-01

    Em situações específicas, os transplantes clínicos cardiopulmonar e pulmonar são, hoje, formas estabelecidas de tratamento para estágio final de doença cardiopulmonar e pulmonar. A obtenção de doadores adequados permanece o maior problema e a remoção de órgãos em localidades distantes é, hoje, uma necessidade. Embora muitos métodos de preservação pulmonar possam ser empregados, para períodos isquémicos de até 5 horas, a hipotermia e o uso de solução cardioplégica com infusão da solução de Col...

  3. Distant nodal metastasis: is it always an unresectable disease?

    Science.gov (United States)

    Celotti, Andrea; Molfino, Sarah; Baggi, Paolo; Tarasconi, Antonio; Baronio, Gianluca; Arru, Luca; Gheza, Federico; Tiberio, Guido; Portolani, Nazario

    2017-01-01

    This article aims at analyzing the published literature concerning the treatment of patients with gastric cancer and distant nodal metastases, actually considered metastatic disease. A systematic search was undertaken using Medline, Embase, Cochrane and Web-of-Science libraries. No specific restriction on year of publication was used; preference was given to English papers. Both clinical series and literature reviews were selected. Only 11 papers address the issue of surgery for nodal basins outside the D2 dissection area. From these papers, in selected cases extended surgery may prove useful in prolonging survival, when a comprehensive therapeutic pathway including chemotherapy is scheduled. In conclusion, in presence of nodal metastases outside the loco-regional nodes, surgery may be considered for metastatic nodes in stations 13 and 16, in selected cases. PMID:28217751

  4. Back-Translation for Discovering Distant Protein Homologies

    Science.gov (United States)

    Gîrdea, Marta; Noé, Laurent; Kucherov, Gregory

    Frameshift mutations in protein-coding DNA sequences produce a drastic change in the resulting protein sequence, which prevents classic protein alignment methods from revealing the proteins’ common origin. Moreover, when a large number of substitutions are additionally involved in the divergence, the homology detection becomes difficult even at the DNA level. To cope with this situation, we propose a novel method to infer distant homology relations of two proteins, that accounts for frameshift and point mutations that may have affected the coding sequences. We design a dynamic programming alignment algorithm over memory-efficient graph representations of the complete set of putative DNA sequences of each protein, with the goal of determining the two putative DNA sequences which have the best scoring alignment under a powerful scoring system designed to reflect the most probable evolutionary process. This allows us to uncover evolutionary information that is not captured by traditional alignment methods, which is confirmed by biologically significant examples.

  5. Connecting The Interstellar Gas And Dust Properties Of Distant Galaxies

    Science.gov (United States)

    Kulkarni, Varsha

    The properties of interstellar gas and dust in distant galaxies are fundamental parameters in constraining galaxy evolution models. Quasar absorption systems (QASs), which trace intervening galaxies along the sightlines to luminous background quasars, provide invaluable tools to directly study gas and dust in distant normal galaxies. Recent studies of QASs have found interesting trends in both gas and dust properties, such as correlations in metallicity with redshift and dust depletions. Our Spitzer spectroscopic studies also indicate that silicate dust grains are present in QASs, and in fact, at a level higher than expected for diffuse gas in the Milky Way. Moreover, the silicate dust grains in these distant galaxies may be substantially more crystalline than those in the Milky Way interstellar medium. We now propose a comprehensive study of the gas and dust properties of all QASs with strong Ly-alpha and/or metal absorption lines that have adequate archival IR data to probe the study of dust. Our analysis will include data primarily from the NASA-supported Spitzer, Herschel, HST, and Keck Observatory archives, along with a small amount of VLT/SDSS archival data. Our specific goals are as follows: (1) We will measure a large range of metal absorption lines in high-resolution quasar spectra from Keck, HST, and VLT archives to uniformly determine the metallicity, dust depletions, ionization, and star formation rates in the foreground QASs. In particular, we will study the variations in these quantities with gas velocity, using Voigt profile fitting techniques to determine the velocity structure. This analysis will also allow us to quantify the kinematics of the absorbing gas. (2) We will use archival Spitzer IRS quasar spectra to search for and measure the strengths of the 10 and 18 micron silicate dust absorption features for a much larger sample of QASs than previously studied. (3) We will fit the observed silicate absorption features in the Spitzer archival

  6. Chandra Finds Well-Established Black Holes In Distant Quasars

    Science.gov (United States)

    2002-03-01

    Pushing further back toward the first generation of objects to form in the universe, NASA's Chandra X-ray Observatory has observed the three most distant known quasars and found them to be prodigious producers of X-rays. This indicates that the supermassive black holes powering them were already in place when the Universe was only about one billion years old. "Chandra's superb sensitivity has allowed the detection of X-rays from the dawn of the modern universe, when the first massive black holes and galaxies were forming," said Niel Brandt of Penn State University, leader of one the teams involved. "These results indicate that future X-ray surveys should be able to detect the first black holes to form in the Universe." The three quasars were recently discovered at optical wavelengths by the Sloan Digital Sky Survey and are 13 billion light years from Earth, making them the most distant known quasars. The X-rays Chandra detected were emitted when the universe was only a billion years old, about 7 percent of the present age of the Universe. Since X-rays reveal conditions in the immediate vicinity of supermassive black holes, Brandt proposed that Chandra look at these objects in three snapshots of about two hours each to see if they were different from their older counterparts. The observations on January 29, 2002 were made public immediately and the four different teams quickly went to work on them. Brandt's team concluded that the quasars looked similar to ones that were at least twice as old, so the conditions around the central black hole had not changed much in that time, contrary to some theoretical expectations. A team led by Smita Mathur of Ohio State University reached a similar conclusion. "These young quasars do not appear to be any different from their older cousins, based upon our current understanding and assumptions," said Mathur. "Perhaps the most remarkable thing about them may be that they are so absolutely unremarkable." Jill Bechtold of the

  7. Van der Waals interactions in rare-gas dimers: The role of interparticle interactions

    CERN Document Server

    Chen, Yu-Ting; Chai, Jeng-Da

    2015-01-01

    We investigate the potential energy curves of rare-gas dimers with various ranges and strengths of interparticle interactions (nuclear-electron, electron-electron, and nuclear-nuclear interactions). Our investigation is based on the highly accurate coupled-cluster theory associated with those interparticle interactions. For comparison, the performance of the corresponding Hartree-Fock theory, second-order Moller-Plesset perturbation theory, and density functional theory is also investigated. Our results reveal that when the interparticle interactions retain the long-range Coulomb tails, the nature of van der Waals interactions in the rare-gas dimers remains similar. By contrast, when the interparticle interactions are sufficiently short-range, the conventional van der Waals interactions in the rare-gas dimers completely disappear, yielding purely repulsive potential energy curves.

  8. Transplantes cardiopulmonar e pulmonar com doador em localidade distante Distant donor procurement for heart-lung and lung transplantation

    OpenAIRE

    Luis Sérgio Fragomeni; Bonser,Robert S; Kaye,Michael P; Stuart W Jamieson

    1988-01-01

    Em situações específicas, os transplantes clínicos cardiopulmonar e pulmonar são, hoje, formas estabelecidas de tratamento para estágio final de doença cardiopulmonar e pulmonar. A obtenção de doadores adequados permanece o maior problema e a remoção de órgãos em localidades distantes é, hoje, uma necessidade. Embora muitos métodos de preservação pulmonar possam ser empregados, para períodos isquémicos de até 5 horas, a hipotermia e o uso de solução cardioplégica com infusão da solução de Col...

  9. Transplantes cardiopulmonar e pulmonar com doador em localidade distante Distant donor procurement for heart-lung and lung transplantation

    Directory of Open Access Journals (Sweden)

    Luis Sérgio Fragomeni

    1988-12-01

    Full Text Available Em situações específicas, os transplantes clínicos cardiopulmonar e pulmonar são, hoje, formas estabelecidas de tratamento para estágio final de doença cardiopulmonar e pulmonar. A obtenção de doadores adequados permanece o maior problema e a remoção de órgãos em localidades distantes é, hoje, uma necessidade. Embora muitos métodos de preservação pulmonar possam ser empregados, para períodos isquémicos de até 5 horas, a hipotermia e o uso de solução cardioplégica com infusão da solução de Collins modificada no tronco pulmonar tem sido método simples e eficiente para preservação do bloco coração-pulmão. Descrevemos, aqui, o método corrente que empregamos, com o qual os transplantes cardiopulmonar e pulmonar combinados foram sucedidos de excelente função cárdio-respiratória.In special situations, clinical heart-lung and lung transplantation are today established methods of therapy for end stage cardiopulmonary and pulmonary disease. Adequate donor availability remains a major problem and distant organ procurement is today a necessity. Although many methods of lung preservation can be used, for periods of up to 5 hours, hypothermic storage with cardioplegic arrest and pulmonary artery flush with modified Collins solution has proven to be a simple and reliable method of heart-lung preservation. We here describe our current method of heart-lung block protection, in which heart-lung and double lung transplantation were performed followed by excelent cardiac and pulmonary function.

  10. The Most Distant Object Yet Discovered in the Universe

    Science.gov (United States)

    2009-04-01

    ESO's Very Large Telescope has shown that a faint gamma-ray burst detected last Thursday is the signature of the explosion of the earliest, most distant known object in the Universe (a redshift of 8.2). The explosion apparently took place more than 13 billion years ago, only about 600 million years after the Big Bang. ESO PR Photo 17a/09 Artist's impression of a gamma-ray burst Gamma-ray bursts (GRBs) are powerful flashes of energetic gamma-rays lasting from less than a second to several minutes. They release a tremendous amount of energy in this short time making them the most powerful events in the Universe. They are thought to be mostly associated with the explosion of stars that collapse into black holes. The gamma-ray burst GRB 090423 was detected by the NASA/STFC/ASI Swift satellite during the morning (CEST) of Thursday 23 April 2009. The 10 second burst was located in the constellation of Leo (the Lion). It was soon being followed by a whole range of telescopes on the ground, including the 2.2-metre ESO/MPG telescope at La Silla and ESO's Very Large Telescope (VLT) at Paranal, both in Chile. VLT infrared observations, made 17 hours after the burst detection, allowed astronomers to establish the distance to the explosion. "We find that the light coming from the explosion has been stretched, or redshifted, considerably by the expansion of the Universe", says Nial Tanvir, the leader of the team who made the VLT observations. "With a redshift of 8.2 this is the most remote gamma-ray burst ever detected, and also the most distant object ever discovered -- by some way." Because light moves at a finite speed, looking farther into the Universe means looking back in time. The explosion occurred when the Universe was about 600 million years old, less than 5 percent of its current age. It is believed that the very first stars only formed when the Universe was between 200 and 400 million years old. "This discovery proves the importance of gamma-ray bursts in probing the

  11. Tree-level equivalence between a Lorentz-violating extension of QED and its dual model in electron-electron scattering

    CERN Document Server

    Toniolo, Giuliano R; Brito, L C T; Scarpelli, A P Baêta

    2016-01-01

    S-matrix amplitudes for the electron-electron scattering are calculated in order to verify the quantum equivalence of dual models. We used an extended Quantum Electrodynamics with CPT-even Lorentz-violating kinetic and mass terms, which was used in a process of gauge embedding, known as Noether dualizationn method (NDM), in order to generate its gauge-invariant dual model. The physical equivalence was established at tree-level and the cross section was calculated to second order in the Lorentz-violating parameter.

  12. Aberrant crossed corticospinal facilitation in muscles distant from a spinal cord injury.

    Directory of Open Access Journals (Sweden)

    Karen L Bunday

    Full Text Available Crossed facilitatory interactions in the corticospinal pathway are impaired in humans with chronic incomplete spinal cord injury (SCI. The extent to which crossed facilitation is affected in muscles above and below the injury remains unknown. To address this question we tested 51 patients with neurological injuries between C2-T12 and 17 age-matched healthy controls. Using transcranial magnetic stimulation we elicited motor evoked potentials (MEPs in the resting first dorsal interosseous, biceps brachii, and tibialis anterior muscles when the contralateral side remained at rest or performed 70% of maximal voluntary contraction (MVC into index finger abduction, elbow flexion, and ankle dorsiflexion, respectively. By testing MEPs in muscles with motoneurons located at different spinal cord segments we were able to relate the neurological level of injury to be above, at, or below the location of the motoneurons of the muscle tested. We demonstrate that in patients the size of MEPs was increased to a similar extent as in controls in muscles above the injury during 70% of MVC compared to rest. MEPs remained unchanged in muscles at and within 5 segments below the injury during 70% of MVC compared to rest. However, in muscles beyond 5 segments below the injury the size of MEPs increased similar to controls and was aberrantly high, 2-fold above controls, in muscles distant (>15 segments from the injury. These aberrantly large MEPs were accompanied by larger F-wave amplitudes compared to controls. Thus, our findings support the view that corticospinal degeneration does not spread rostral to the lesion, and highlights the potential of caudal regions distant from an injury to facilitate residual corticospinal output after SCI.

  13. Beyond 3 AU from the Sun: "Hypervolatiles" in Distant Comets

    Science.gov (United States)

    Bonev, Boncho P.; Villanueva, Geronimo Luis; Mumma, Michael J.; DiSanti, Michael A.; Paganini, Lucas; Boehnhardt, Hermann; Lippi, Manuela; Gibb, Erika L.; Bockelee-Morvan, Dominique; de Val-Borro, Miguel; Kawakita, Hideyo; Altwegg, Kathrin

    2016-10-01

    Our understanding of inner coma composition in comets has long been biased towards heliocentric distances (Rh) smaller than 2-3 AU. However, observations far from the Sun are also of high value for better understanding the nucleus structure and outgassing of volatiles. Substantial and very important evidence for the activity of distant comets has been accumulated from photometry and analyses of light curves, but direct detections of primary (parent) volatiles are still rare. For example, comet C/2006 W3 (Christensen) remained outside 3.1 AU throughout its apparition, yet it presented the best opportunity since Hale-Bopp (1997) for detailed spectroscopic studies in a distant comet. C/2006 W3 was observed from several space- and ground-based facilities using both infrared and radio techniques. CO, CH4, and C2H6 were measured via infrared spectroscopy at ESO-VLT at Rh = 3.25 AU. Production rates were found to exceed those measured for each of these species in most other comets, despite those comets being observed much closer to the Sun. With its relatively high CO/CO2 ratio, C/2006 W3 also appears as an outlier in the AKARI comet survey of 18 comets. The detections of H2O (Herschel Space Observatory) and CO (ESO-VLT) allow for constraining the coma abundance ratio H2O/CO at Rh = 5 AU.We will compare the C2H6/CH4/CO ratios in C/2006 W3 with those in other comets spanning a large range in Rh: from D/2012 S1 ISON (~0.7 AU) to 29P/Schwassmann-Wachmann 1 (~ 6.3 AU). Notably in situ measurements by the Rosetta mission were performed in the coma of 67P/Churyumov-Gerasimenko, at a very similar heliocentric distance to C/2006 W3 (3.15 AU). While comparisons of column-integrated remote sensing measurements and abundances from in-situ mass spectrometry (as performed by the ROSINA instrument) are not straightforward, both types of measurement are of high value for constraining models of nucleus outgassing beyond 3 AU from the Sun, where the inferred nucleus structure and

  14. Neutral sheet crossings by ISEE-3 in the distant magnetotail

    Science.gov (United States)

    Heikkila, W. J.; Slavin, J. A.; Smith, E. J.; Baker, D. N.; Zwickl, R. D.

    1986-01-01

    The magnetic field data from ISEE-3 in the distant magnetotail at crossings of the field reversal (or neutral sheet) region are analyzed to determine the instantaneous direction of the normal component B(z) at the crossing. Crossings in the middle of the aberrated magnetotail near the apogee A2 of the first deep-tail orbit of ISEE-3 in January-February, 1983 were selected. Data for an interval of one hour is discussed at length to illustrate some of the difficulties that can occur. One particular smooth crossing at 15:56 UT, February 4, 1983, shows that complicated microstructure can occur in times shorter than one minute; averaging over long times may eliminate essential information for this purpose. By inspecting the magnetic field data at the highest resolution, however, it is shown that the direction of the plasma sheet flows and the sense of B(z) across the neutral sheet do not always agree with the reconnection models. Rather, they indicate that the low latitude boundary layer may play a significant role in the dynamics of the magnetotail.

  15. The life-cycle of star formation in distant clusters

    CERN Document Server

    Barger, A J; Ellis, Richard S; Couch, W J; Smail, I; Sharples, R M

    1995-01-01

    We analyse the detailed distribution of star-forming and post-starburst members in three distant (z = 0.31) galaxy clusters in terms of evolutionary sequences that incorporate secondary bursts of star formation on pre-existing stellar populations. Using the number density of spectroscopically-confirmed members on the EW(H\\delta) versus B-R plane from existing data, and for a larger K'-limited sample on the U-I versus I-K' plane from newly-acquired infrared images, we demonstrate that the proportion of cluster members undergoing secondary bursts of star formation during the last ~2 Gyr prior to the epoch of observation is probably as high as 30 per cent of the member galaxies. A key observation leading to this conclusion is the high proportion of H\\delta strong galaxies in all three clusters. The evolutionary modelling, whilst necessarily approximate, returns the correct proportions of galaxies in various stages of the star formation cycle both in terms of spectral and colour properties. HST images for the thr...

  16. "Neuropeptides in the brain defense against distant organ damage".

    Science.gov (United States)

    Hamasaki, Mike Yoshio; Barbeiro, Hermes Vieira; Barbeiro, Denise Frediani; Cunha, Débora Maria Gomes; Koike, Marcia Kiyomi; Machado, Marcel Cerqueira César; Pinheiro da Silva, Fabiano

    2016-01-15

    Delirium, or acute confusional state, is a common manifestation in diseases that originate outside the central nervous system, affecting 30-40% of elderly hospitalized patients and up to 80% of the critically ill, even though it remains unclear if severe systemic inflammation is able or not to induce cellular disturbances and immune activation in the brain. Neuropeptides are pleotropic molecules heterogeneously distributed throughout the brain and possess a wide spectrum of functions, including regulation of the inflammatory response, so we hypothesized that they would be the major alarm system in the brain before overt microglia activation. In order to investigate this hypothesis, we induced acute pancreatitis in 8-10week old rats and collected brain tissue, 12 and 24h following pancreatic injury, to measure neuropeptide and cytokine tissue levels. We found significantly higher levels of β-endorphin, orexin and oxytocin in the brain of rats submitted to pancreatic injury, when compared to healthy controls. Interestingly, these differences were not associated with increased local cytokine levels, putting in evidence that neuropeptide release occurred independently of microglia activation and may be a pivotal alarm system to initiate neurologic reactions to distant inflammatory non-infectious aggression.

  17. BLAST: the far-infrared/radio correlation in distant galaxies

    CERN Document Server

    Ivison, R J; Biggs, Andy D; Brandt, W N; Chapin, Edward L; Coppin, Kristen E K; Devlin, Mark J; Dickinson, Mark; Dunlop, James; Dye, Simon; Eales, Stephen A; Frayer, David T; Halpern, Mark; Hughes, David H; Ibar, Edo; Kovács, A; Marsden, Gaelen; Moncelsi, L; Netterfield, Calvin B; Pascale, Enzo; Patanchon, Guillaume; Rafferty, D A; Rex, Marie; Schinnerer, Eva; Scott, Douglas; Semisch, C; Smail, Ian; Swinbank, A M; Truch, Matthew D P; Tucker, Gregory S; Viero, Marco P; Walter, Fabian; Weiss, Axel; Wiebe, Donald V; Xue, Y Q

    2009-01-01

    We investigate the correlation between FIR and radio luminosities in distant galaxies, a lynchpin of modern astronomy. We use data from BLAST, Spitzer, LABOCA, the VLA and the GMRT in the ECDFS. For a catalogue of BLAST 250um-selected galaxies, we re-measure the 70-870um flux densities at the positions of their most likely 24um counterparts, which have a median [interquartile] redshift of 0.74 [0.25, 1.57]. From these, we determine the monochromatic flux density ratio, q_250 (= log_10 [S_250um/S_1,400MHz]), and the bolometric equivalent, q_IR. At z~0.6, where our 250um filter probes rest-frame 160um emission, we find no evolution relative to q_160 for local galaxies. We also stack the FIR and submm images at the positions of 24um- and radio-selected galaxies. The difference between q_IR seen for 250um- and radio-selected galaxies suggests star formation provides most of the IR luminosity in <~100uJy radio galaxies, but rather less for those in the mJy regime. For the 24um sample, the radio spectral index i...

  18. Possible signature of distant foreground in the Planck data

    CERN Document Server

    Yershov, V N; Raikov, A A

    2014-01-01

    By using the Planck map of the cosmic microwave background (CMB) radiation we have checked and confirmed the existence of a correlation between supernova (SN) redshifts, $z_{\\rm SN}$, and CMB temperature fluctuations at the SNe locations, $T_{\\rm SN}$, which we previously reported for the Wilkinson Microwave Anisotropy Probe data. The Pearson correlation coefficient for the Planck data is $r=+0.38\\pm 0.08$ which indicates that the correlation is statistically significant (the signal is about $5\\sigma$ above the noise level). The correlation becomes even stronger for the type Ia subsample of SNe, $r_{\\rm Ia}=+0.45\\pm 0.09$, whereas for the rest of the SNe it is vanishing. By checking the slopes of the regression lines $T_{\\rm SN} / z_{\\rm SN}$ for Planck's different frequency bands we have also excluded the possibility of this anomaly being caused by the Sunyaev-Zeldovich effect. The remaining possibility is some, unaccounted for, contribution to the CMB from distant ($z>0.3$) foreground through either the int...

  19. Chemical abundances of distant extremely metal-poor unevolved stars

    CERN Document Server

    Bonifacio, P; Caffau, E; Ludwig, H -G; Spite, M; Hernández, J I González; Behara, N T

    2012-01-01

    Aims: The purpose of our study is to determine the chemical composition of a sample of 16 candidate Extremely Metal-Poor (EMP) dwarf stars, extracted from the Sloan Digital Sky Survey (SDSS). There are two main purposes: in the first place to verify the reliability of the metallicity estimates derived from the SDSS spectra; in the second place to see if the abundance trends found for the brighter nearer stars studied previously also hold for this sample of fainter, more distant stars. Methods: We used the UVES at the VLT to obtain high-resolution spectra of the programme stars. The abundances were determined by an automatic analysis with the MyGIsFOS code, with the exception of lithium, for which the abundances were determined from the measured equivalent widths of the Li I resonance doublet. Results: All candidates are confirmed to be EMP stars, with [Fe/H]<= -3.0. The chemical composition of the sample of stars is similar to that of brighter and nearer samples. We measured the lithium abundance for 12 st...

  20. Limiting the dimming of distant type Ia supernovae

    CERN Document Server

    Ostman, L; Ostman, Linda; Mortsell, Edvard

    2005-01-01

    Distant supernovae have been observed to be fainter than what is expected in a matter dominated universe. The most likely explanation is that the universe is dominated by an energy component with negative pressure -- dark energy. However, there are several astrophysical processes that could, in principle, affect the measurements and in order to be able to take advantage of the growing supernova statistics, the control of systematic effects is crucial. We discuss two of these; extinction due to intergalactic grey dust and dimming due to photon-axion oscillations and show how their effect on supernova observations can be constrained using observed quasar colours and spectra. For a wide range of intergalactic dust models, we are able to rule out any dimming larger than 0.2 magnitudes for a type Ia supernova at z=1. The corresponding limit for intergalactic Milky Way type dust is 0.03 mag. For the more speculative model of photons mixing with axions, we find that the effect is independent of photon energy for cer...

  1. The Science Case for PILOT II: the Distant Universe

    CERN Document Server

    Lawrence, J S; Bunker, A; Bouwens, R; Burgarella, D; Burton, M G; Gehrels, N; Glazebrook, K; Pimbblet, K; Quimby, R; Saunders, W; Storey, J W V; Wheeler, J C

    2009-01-01

    PILOT (the Pathfinder for an International Large Optical Telescope) is a proposed 2.5 m optical/infrared telescope to be located at Dome C on the Antarctic plateau. The atmospheric conditions at Dome C deliver a high sensitivity, high photometric precision, wide-field, high spatial resolution, and high-cadence imaging capability to the PILOT telescope. These capabilities enable a unique scientific potential for PILOT, which is addressed in this series of papers. The current paper presents a series of projects dealing with the distant (redshift >) Universe, that have been identified as key science drivers for the PILOT facility. The potential for PILOT to detect the first populations of stars to form in the early Universe, via infrared projects searching for pair-instability supernovae and gamma-ray burst afterglows, is investigated. Two projects are proposed to examine the assembly and evolution of structure in the Universe: an infrared survey searching for the first evolved galaxies at high redshift, and an ...

  2. Realigning Thunder and Lightning: Temporal Adaptation to Spatiotemporally Distant Events

    Science.gov (United States)

    Navarra, Jordi; Fernández-Prieto, Irune; Garcia-Morera, Joel

    2013-01-01

    The brain is able to realign asynchronous signals that approximately coincide in both space and time. Given that many experience-based links between visual and auditory stimuli are established in the absence of spatiotemporal proximity, we investigated whether or not temporal realignment arises in these conditions. Participants received a 3-min exposure to visual and auditory stimuli that were separated by 706 ms and appeared either from the same (Experiment 1) or from different spatial positions (Experiment 2). A simultaneity judgment task (SJ) was administered right afterwards. Temporal realignment between vision and audition was observed, in both Experiment 1 and 2, when comparing the participants’ SJs after this exposure phase with those obtained after a baseline exposure to audiovisual synchrony. However, this effect was present only when the visual stimuli preceded the auditory stimuli during the exposure to asynchrony. A similar pattern of results (temporal realignment after exposure to visual-leading asynchrony but not after exposure to auditory-leading asynchrony) was obtained using temporal order judgments (TOJs) instead of SJs (Experiment 3). Taken together, these results suggest that temporal recalibration still occurs for visual and auditory stimuli that fall clearly outside the so-called temporal window for multisensory integration and appear from different spatial positions. This temporal realignment may be modulated by long-term experience with the kind of asynchrony (vision-leading) that we most frequently encounter in the outside world (e.g., while perceiving distant events). PMID:24391928

  3. Estimating sizes of faint, distant galaxies in the submillimetre regime

    CERN Document Server

    Lindroos, L; Fan, L; Conway, J; Coppin, K; Decarli, R; Drouart, G; Hodge, J A; Karim, A; Simpson, J M; Wardlow, J

    2016-01-01

    We measure the sizes of redshift ~2 star-forming galaxies by stacking data from the Atacama Large Millimeter/submillimeter Array (ALMA). We use a uv-stacking algorithm in combination with model fitting in the uv-domain and show that this allows for robust measures of the sizes of marginally resolved sources. The analysis is primarily based on the 344 GHz ALMA continuum observations centred on 88 sub-millimeter galaxies in the LABOCA ECDFS Submillimeter Survey (ALESS). We study several samples of galaxies at z~2 with $M_* \\sim{} 5\\times{}10^{10} $ M$_\\odot$ , selected using near-infrared photometry (distant red galaxies, extremely red objects, sBzK-galaxies, and galaxies selected on photometric redshift). We find that the typical sizes of these galaxies are ~0.6 arcsec which corresponds to ~5 kpc at z~2, this agrees well with the median sizes measured in the near-infrared z-band (~0.6 arcsec). We find errors on our size estimates of ~0.1-0.2 arcsec, which agree well with the expected errors for model fitting a...

  4. Realigning thunder and lightning: temporal adaptation to spatiotemporally distant events.

    Directory of Open Access Journals (Sweden)

    Jordi Navarra

    Full Text Available The brain is able to realign asynchronous signals that approximately coincide in both space and time. Given that many experience-based links between visual and auditory stimuli are established in the absence of spatiotemporal proximity, we investigated whether or not temporal realignment arises in these conditions. Participants received a 3-min exposure to visual and auditory stimuli that were separated by 706 ms and appeared either from the same (Experiment 1 or from different spatial positions (Experiment 2. A simultaneity judgment task (SJ was administered right afterwards. Temporal realignment between vision and audition was observed, in both Experiment 1 and 2, when comparing the participants' SJs after this exposure phase with those obtained after a baseline exposure to audiovisual synchrony. However, this effect was present only when the visual stimuli preceded the auditory stimuli during the exposure to asynchrony. A similar pattern of results (temporal realignment after exposure to visual-leading asynchrony but not after exposure to auditory-leading asynchrony was obtained using temporal order judgments (TOJs instead of SJs (Experiment 3. Taken together, these results suggest that temporal recalibration still occurs for visual and auditory stimuli that fall clearly outside the so-called temporal window for multisensory integration and appear from different spatial positions. This temporal realignment may be modulated by long-term experience with the kind of asynchrony (vision-leading that we most frequently encounter in the outside world (e.g., while perceiving distant events.

  5. Dam removal increases American eel abundance in distant headwater streams

    Science.gov (United States)

    Hitt, Nathaniel P.; Eyler, Sheila; Wofford, John E.B.

    2012-01-01

    American eel Anguilla rostrata abundances have undergone significant declines over the last 50 years, and migration barriers have been recognized as a contributing cause. We evaluated eel abundances in headwater streams of Shenandoah National Park, Virginia, to compare sites before and after the removal of a large downstream dam in 2004 (Embrey Dam, Rappahannock River). Eel abundances in headwater streams increased significantly after the removal of Embrey Dam. Observed eel abundances after dam removal exceeded predictions derived from autoregressive models parameterized with data prior to dam removal. Mann–Kendall analyses also revealed consistent increases in eel abundances from 2004 to 2010 but inconsistent temporal trends before dam removal. Increasing eel numbers could not be attributed to changes in local physical habitat (i.e., mean stream depth or substrate size) or regional population dynamics (i.e., abundances in Maryland streams or Virginia estuaries). Dam removal was associated with decreasing minimum eel lengths in headwater streams, suggesting that the dam previously impeded migration of many small-bodied individuals (dams may influence eel abundances in headwater streams up to 150 river kilometers distant, and that dam removal may provide benefits for eel management and conservation at the landscape scale.

  6. Distant Compact Clusters of Galaxies from the BMW survey

    Science.gov (United States)

    Dell'Antonio, Ian; Guzzo, Luigi; Longhetti, Marcella; Moretti, Alberto; Campana, Sergio; Lazzati, Davide; Panzera, Mariarosa; Tagliaferri, Gianpiero

    2002-02-01

    We propose to use SQIID to identify high-redshift clusters of galaxies from the BMW, an X-ray selected sample of serendipitously detected extended sources from the ROSAT HRI archive. The BMW survey is unique because of the superior angular resolution of the HRI. In fact, this is the only modern sample of distant clusters available that is not based on the low-resolution PSPC. Using 4m optical imaging, we have already identified several high-redshift clusters, two of which have z> 0.8, thus confirming the ability of the survey to peer efficiently into the z~ 1 regime, where only a handful of X-ray clusters are known. To test the evolution of the cluster abundance, we must increase the number of clusters known in this redshift regime. The BMW survey provides us with the only current opportunity to study compact clusters missing in all PSPC surveys. Because z~ 1 ellipticals have very red colors, K-band imaging is the most effective way of identifying these clusters. With SQIID, we also can obtain redshift estimates via the J-K red sequence. We propose near-IR imaging in J,H,K of 30 highest-z cluster candidates from the BMW survey, as indicated by their small size and low flux. This will allow efficient use of 8-meter spectroscopy to follow up the high-end tail of the redshift distribution.

  7. Endogenous Arabidopsis messenger RNAs transported to distant tissues.

    Science.gov (United States)

    Thieme, Christoph J; Rojas-Triana, Monica; Stecyk, Ewelina; Schudoma, Christian; Zhang, Wenna; Yang, Lei; Miñambres, Miguel; Walther, Dirk; Schulze, Waltraud X; Paz-Ares, Javier; Scheible, Wolf-Rüdiger; Kragler, Friedrich

    2015-03-23

    The concept that proteins and small RNAs can move to and function in distant body parts is well established. However, non-cell-autonomy of small RNA molecules raises the question: To what extent are protein-coding messenger RNAs (mRNAs) exchanged between tissues in plants? Here we report the comprehensive identification of 2,006 genes producing mobile RNAs in Arabidopsis thaliana. The analysis of variant ecotype transcripts that were present in heterografted plants allowed the identification of mRNAs moving between various organs under normal or nutrient-limiting conditions. Most of these mobile transcripts seem to follow the phloem-dependent allocation pathway transporting sugars from photosynthetic tissues to roots via the vasculature. Notably, a high number of transcripts also move in the opposite, root-to-shoot direction and are transported to specific tissues including flowers. Proteomic data on grafted plants indicate the presence of proteins from mobile RNAs, allowing the possibility that they may be translated at their destination site. The mobility of a high number of mRNAs suggests that a postulated tissue-specific gene expression profile might not be predictive for the actual plant body part in which a transcript exerts its function.

  8. Weak lensing mass reconstructions of the ESO Distant Cluster Survey

    CERN Document Server

    Clowe, D; Aragón-Salamanca, A; Bremer, M; De Lucia, G; Halliday, C; Jablonka, P; Milvang-Jensen, B; Pellò, R; Poggianti, B M; Rudnick, G; Saglia, R; Simard, L; White, S; Zaritsky, D

    2005-01-01

    We present weak lensing mass reconstructions for the 20 high-redshift clusters i n the ESO Distant Cluster Survey. The weak lensing analysis was performed on deep, 3-color optical images taken with VLT/FORS2, using a composite galaxy catalog with separate shape estimators measured in each passband. We find that the EDisCS sample is composed primarily of clusters that are less massive than t hose in current X-ray selected samples at similar redshifts, but that all of the fields are likely to contain massive clusters rather than superpositions of low mass groups. We find that 7 of the 20 fields have additional massive structures which are not associated with the clusters and which can affect the weak lensing mass determination. We compare the mass measurements of the remaining 13 clusters with luminosity measurements from cluster galaxies selected using photometric redshifts and find evidence of a dependence of the cluster mass-to-light ratio with redshift. Finally we determine the noise level in the shear meas...

  9. Radio Selection of the Most Distant Galaxy Clusters

    Science.gov (United States)

    Daddi, E.; Jin, S.; Strazzullo, V.; Sargent, M. T.; Wang, T.; Ferrari, C.; Schinnerer, E.; Smolčić, V.; Calabró, A.; Coogan, R.; Delhaize, J.; Delvecchio, I.; Elbaz, D.; Gobat, R.; Gu, Q.; Liu, D.; Novak, M.; Valentino, F.

    2017-09-01

    We show that the most distant X-ray-detected cluster known to date, Cl J1001 at {z}{spec}=2.506, hosts a strong overdensity of radio sources. Six of them are individually detected (within 10\\prime\\prime ) in deep 0\\buildrel{\\prime\\prime}\\over{.} 75 resolution VLA 3 GHz imaging, with {S}3{GHz}> 8 μ {Jy}. Of the six, an active galactic nucleus (AGN) likely affects the radio emission in two galaxies, while star formation is the dominant source powering the remaining four. We searched for cluster candidates over the full COSMOS 2 deg2 field using radio-detected 3 GHz sources and looking for peaks in {{{Σ }}}5 density maps. Cl J1001 is the strongest overdensity by far with > 10σ , with a simple {z}{phot}> 1.5 preselection. A cruder photometric rejection of zgeneration of forming galaxy clusters. In these remarkable structures, widespread star formation and AGN activity of massive galaxy cluster members, residing within the inner cluster core, will ultimately lead to radio continuum as one of the most effective means for their identification, with detection rates expected in the ballpark of 0.1–1 per square degree at z≳ 2.5. Samples of hundreds such high-redshift clusters could potentially constrain cosmological parameters and test cluster and galaxy formation models.

  10. Linear temperature behavior of thermopower and strong electron-electron scattering in thick F-doped SnO{sub 2} films

    Energy Technology Data Exchange (ETDEWEB)

    Lang, Wen-Jing; Li, Zhi-Qing, E-mail: zhiqingli@tju.edu.cn [Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, Department of Physics, Tianjin University, Tianjin 300072 (China)

    2014-07-28

    Both the semi-classical and quantum transport properties of F-doped SnO{sub 2} thick films (∼1 μm) were investigated experimentally. We found that the resistivity caused by the thermal phonons obeys Bloch-Grüneisen law from ∼90 to 300 K, while only the diffusive thermopower, which varies linearly with temperature from 300 down to 10 K, can be observed. The phonon-drag thermopower is completely suppressed due to the long electron-phonon relaxation time in the compound. These observations, together with the fact that the carrier concentration has negligible temperature dependence, indicate that the conduction electrons in F-doped SnO{sub 2} films possess free-electron-like characteristics. At low temperatures, the electron-electron scattering dominates over the electron-phonon scattering and governs the inelastic scattering process. The theoretical predications of scattering rates of large- and small-energy-transfer electron-electron scattering processes, which are negligibly weak in three-dimensional disordered conventional conductors, are quantitatively tested in this lower carrier concentration and free-electron-like highly degenerate semiconductor.

  11. Sistema interactivo de aprendizaje como elemento de apoyo a los procesos de sustentabilidad y educación inclusiva, aplicado en comunidades lejanas de la República Democrática del Congo Interactive learning system as a support in processes of sustainability and inclusive education, applied in distant communities of the Democratic Republic of Congo

    Directory of Open Access Journals (Sweden)

    Gilmar Rolando Anaguano Jiménez

    2010-01-01

    Full Text Available El presente es un artículo de reflexión, el cual resalta la importancia de los ambientes virtuales de aprendizaje como estrategia de apoyo a los lineamientos actuales de las Naciones Unidas, relacionados con los procesos de sustentabilidad global y educación inclusiva. Contiene la reflexión y descripción, de una investigación realizada por dos integrantes del grupo ARKADIUS del programa en Ingeniería de Sistemas de la Universidad de Medellín, cuyo objetivo general consistió en diseñar un sistema interactivo de aprendizaje para La República Democrática del Congo - África. Metodológicamente fue una investigación de tipo aplicativo-experimental la cual generó un prototipo de software diseñado a la medida para apoyar las estrategias postuladas por la teoría de aprendizaje mixto (B-Learning. El modelo pedagógico sugerido, las herramientas tecnológicas utilizadas y la movilización de un equipo investigativo internacional interdisciplinario constituyen igualmente, un aporte a los procesos de internacionalización y proyección social de la educación.This document is a reflection, which highlights the importance of the virtual learning environments as strategy to support the current tendencies of the United Nations, related to the processes of global sustainability and inclusive education. It contains the reflection and description of a research carried out by two members of the ARKADIUS research group of Computer Science Engineering program of Universidad de Medellín; which general target consisted of designing an interactive learning system for the Democratic Republic of Congo - Africa. Methodologically it was an applicative-experimental research, which generated a prototype of software tailored to support the strategies stated by the theory of Blended Learning. The pedagogic model suggested, technological tools used, and the mobilization of an international and interdisciplinary research team, can be considered as a

  12. 76 FR 31351 - Safety Requirements and Manning Exemption Eligibility on Distant Water Tuna Fleet Vessels

    Science.gov (United States)

    2011-05-31

    ... SECURITY Coast Guard Safety Requirements and Manning Exemption Eligibility on Distant Water Tuna Fleet... availability of Office of Vessel Activities Policy Letter 11-05 regarding Distant Water Tuna Fleet vessels manning exemption eligibility and safety requirements. This final policy clarifies the requirements...

  13. Lire de près, de loin: close vs distant reading

    NARCIS (Netherlands)

    Laurel, M.H.A.; Jesus Cabral, M. de; Schuerewegen, F.M.J.

    2014-01-01

    Since the work of Franco Moretti, 'distant reading' has become a research method in literature departments. But what is at stake in this kind of reading? Are 'close reading' and 'distant reading' really opposites or can both these approaches be employed at the same time?

  14. Automatic Camera Control System for a Distant Lecture with Videoing a Normal Classroom.

    Science.gov (United States)

    Suganuma, Akira; Nishigori, Shuichiro

    The growth of a communication network technology enables students to take part in a distant lecture. Although many lectures are conducted in universities by using Web contents, normal lectures using a blackboard are still held. The latter style lecture is good for a teacher's dynamic explanation. A way to modify it for a distant lecture is to…

  15. PSF subtraction to search for distant Jupiters with SPITZER

    Science.gov (United States)

    Rameau, Julien; Artigau, Etienne; Baron, Frédérique; Lafrenière, David; Doyon, Rene; Malo, Lison; Naud, Marie-Eve; Delorme, Philippe; Janson, Markus; Albert, Loic; Gagné, Jonathan; Beichman, Charles

    2015-12-01

    In the course of the search for extrasolar planets, a focus has been made towards rocky planets very close (within few AUs) to their parent stars. However, planetary systems might host gas giants as well, possibly at larger separation from the central star. Direct imaging is the only technique able to probe the outer part of planetary systems. With the advent of the new generation of planet finders like GPI and SPHERE, extrasolar systems are now studied at the solar system scale. Nevertheless, very extended planetary systems do exist and have been found (Gu Ps, AB Pic b, etc.). They are easier to detect and characterize. They are also excellent proxy for close-in gas giants that are detected from the ground. These planets have no equivalent in our solar system and their origin remain a matter of speculation. In this sense, studying planetary systems from its innermost to its outermost part is therefore mandatory to have a clear understanding of its architecture, hence hints of its formation and evolution. We are carrying out a space-based survey using SPITZER to search for distant companions around a well-characterized sample of 120 young and nearby stars. We designed an observing strategy that allows building a very homogeneous PSF library. With this library, we perform a PSF subtraction to search for planets from 10’’ down to 1’’. In this poster, I will present the library, the different algorithms used to subtract the PSF, and the promising detection sensitivity that we are able to reach with this survey. This project to search for the most extreme planetary systems is unique in the exoplanet community. It is also the only realistic mean of directly imaging and subsequently obtaining spectroscopy of young Saturn or Jupiter mass planets in the JWST-era.

  16. A numerical experiment on light pollution from distant sources

    Science.gov (United States)

    Kocifaj, M.

    2011-08-01

    To predict the light pollution of the night-time sky realistically over any location or measuring point on the ground presents quite a difficult calculation task. Light pollution of the local atmosphere is caused by stray light, light loss or reflection of artificially illuminated ground objects or surfaces such as streets, advertisement boards or building interiors. Thus it depends on the size, shape, spatial distribution, radiative pattern and spectral characteristics of many neighbouring light sources. The actual state of the atmospheric environment and the orography of the surrounding terrain are also relevant. All of these factors together influence the spectral sky radiance/luminance in a complex manner. Knowledge of the directional behaviour of light pollution is especially important for the correct interpretation of astronomical observations. From a mathematical point of view, the light noise or veil luminance of a specific sky element is given by a superposition of scattered light beams. Theoretical models that simulate light pollution typically take into account all ground-based light sources, thus imposing great requirements on CPU and MEM. As shown in this paper, a contribution of distant sources to the light pollution might be essential under specific conditions of low turbidity and/or Garstang-like radiative patterns. To evaluate the convergence of the theoretical model, numerical experiments are made for different light sources, spectral bands and atmospheric conditions. It is shown that in the worst case the integration limit is approximately 100 km, but it can be significantly shortened for light sources with cosine-like radiative patterns.

  17. PN populations in the local group and distant stellar populations

    Science.gov (United States)

    Reid, Warren

    2016-08-01

    Our understanding of galactic structure and evolution is far from complete. Within the past twelve months we have learnt that the Milky Way is about 50% wider than was previously thought. As a consequence, new models are being developed that force us to reassess the kinematic structure of our Galaxy. Similarly, we need to take a fresh look at the halo structure of external galaxies in our Local Group. Studies of stellar populations, star-forming regions, clusters, the interstellar medium, elemental abundances and late stellar evolution are all required in order to understand how galactic assembly has occurred as we see it. PNe play an important role in this investigation by providing a measure of stellar age, mass, abundances, morphology, kinematics and synthesized matter that is returned to the interstellar medium (ISM). Through a method of chemical tagging, halo PNe can reveal evidence of stellar migration and galactic mergers. This is an outline of the advances that have been made towards uncovering the full number of PNe in our Local Group galaxies and beyond. Current numbers are presented and compared to total population estimates based on galactic mass and luminosity. A near complete census of PNe is crucial to understanding the initial-to-final mass relation for stars with mass >1 to mass of the sun. It also allows us to extract more evolutionary information from luminosity functions and compare dust-to-gas ratios from PNe in different galactic locations. With new data provided by the Gaia satellite, space-based telescopes and the rise of giant and extra-large telescopes, we are on the verge of observing and understanding objects such as PNe in distant galaxies with the same detail we expected from Galactic observations only a decade ago.

  18. APPLICATION OF MICROPHONE ARRAYS FOR DISTANT SPEECH CAPTURE

    Directory of Open Access Journals (Sweden)

    M. B. Stolbov

    2015-07-01

    Full Text Available Application of microphone arrays and beamforming techniques for speech information collection has significant advantages compared to systems operating with a single microphone. This paper presents a brief overview of microphone array systems for collecting distant speech information. The paper is based on an analysis of publications on the use of microphone arrays for speech information collection tasks, as well as on the author’s experience in the development and practical application of planar microphone arrays. The paper describes the main stages of the development of systems for remote capture of audio information. It provides a review of the main applications of microphone arrays, the basic types of microphone arrays and their features. The bulk of the paper deals with planar microphone arrays. We analyze the work of microphone arrays in different acoustic environments. The paper contains the basic equations for calculating the parameters of equidistant planar microphone arrays. Some methods of designing non-equidistant arrays are also mentioned (a list of references is included. We also provide a list of basic digital signal processing algorithms for planar microphone arrays, as well as a list of references on processing algorithms in the frequency domain. The paper includes a list of foreign companies offering systems based on microphone arrays for a wide range of tasks associated with the processing of speech and audio signals. We describe some state-of-the-art speech information collection systems based on microphone arrays. Some promising directions for the development of speech information collection systems using microphone arrays are described in conclusion. The material of the review is usable in designing of microphone arrays for specific practical applications.

  19. Waiting for Shadows from the Distant Solar System

    Science.gov (United States)

    Kohler, Susanna

    2016-03-01

    How can we hope to measure the hundreds of thousands of objects in our distant solar system? A team of astronomers is harnessing citizen science to begin to tackle this problem!A light curve from an occultation collected by a RECON site in Quincy, California. As the objects shadow passes, the background stars light dims. [RECON/Charley Arrowsmith (Feather River College)]Occultation InformationEstimates currently place the number of Kuiper belt objects larger than 100 km across at over 100,000. Knowing the sizes and characteristics of these objects is important for understanding the composition of the outer solar system and constraining models of the solar systems formation and evolution.Unfortunately, measuring small, dim bodies at large distances is incredibly difficult! One of the best ways to obtain the sizes of these objects is to watch as they occult a distant star. Timing the object as it passes across the face of the star can give us a good measure of its size and shape, when observed from multiple stations in the path of the shadow.An Extended NetworkOccultations by nearby objects (like main-belt asteroids) can be predicted fairly accurately, but those by trans-Neptunian objects are much more poorly constrained. Only ~900 trans-Neptunian objects have approximately known paths, and occultation-shadow predictions for these objects are often only accurate to ~1000km on the Earths surface. So how can we ensure that theres a telescope in the right location, ready to observe when an occultation occurs?Map of the 56 RECON sites distributed over 2000 km in the western United States. [Buie et al. 2016]The simplest answer is to set up a huge network of observing stations, and wait for the shadows to come to the network. With this approach, even if the predicted path isnt precisely known, some of the stations will still observe the occultation.Due to the number of stations needed, this project lends itself perfectly to citizen science. In a recently published paper by

  20. Most Distant Group of Galaxies Known in the Universe

    Science.gov (United States)

    2002-04-01

    New VLT Discovery Pushes Back the Beginnings Summary Using the ESO Very Large Telescope (VLT) , a team of astronomers from The Netherlands, Germany, France and the USA [1] have discovered the most distant group of galaxies ever seen , about 13.5 billion light-years away. It has taken the light now recorded by the VLT about nine-tenths of the age of the Universe to cover the huge distance. We therefore observe those galaxies as they were at a time when the Universe was only about 10% of its present age . The astronomers conclude that this group of early galaxies will develop into a rich cluster of galaxies, such as those seen in the nearby Universe. The newly discovered structure provides the best opportunity so far for studying when and how galaxies began to form clusters after the initial Big Bang , one of the greatest puzzles in modern cosmology. PR Photo 11a/02 : Sky field with the distant cluster of galaxies. PR Photo 11b/02 : Spectra of some of the galaxies in the cluster. Radio Galaxies as cosmic signposts A most intriguing question in modern astronomy is how the first groupings or "clusters" of galaxies emerged from the gas produced in the Big Bang. Some theoretical models predict that densely populated galaxy clusters ("rich clusters" in current astronomical terminology) are built up through a step-wise process. Clumps develop in the primeval gas, and stars condense out of these clumps to form small galaxies. Then these small galaxies merge together to form larger units. The peculiar class of "radio galaxies" is particularly important for investigating such scenarios. They are called so because their radio emission - a result of violent processes believed to be related to massive black holes located at the centres of these galaxies - is stronger by 5 - 10 orders of magnitude than that of our own Milky Way galaxy. In fact, this radio emission is often so intense that the galaxies can be spotted at extremely large distances, and thus at the remote epoch when

  1. Farthest Neighbor: The Distant Milky Way Satellite Eridanus II

    Energy Technology Data Exchange (ETDEWEB)

    Li, T. S.; Simon, J. D.; Drlica-Wagner, A.; Bechtol, K.; Wang, M. Y.; García-Bellido, J.; Frieman, J.; Marshall, J. L.; James, D. J.; Strigari, L.; Pace, A. B.; Balbinot, E.; Zhang, Y.; Abbott, T. M. C.; Allam, S.; Benoit-Lévy, A.; Bernstein, G. M.; Bertin, E.; Brooks, D.; Burke, D. L.; Rosell, A. Carnero; Kind, M. Carrasco; Carretero, J.; Cunha, C. E.; D’Andrea, C. B.; Costa, L. N. da; DePoy, D. L.; Desai, S.; Diehl, H. T.; Eifler, T. F.; Flaugher, B.; Goldstein, D. A.; Gruen, D.; Gruendl, R. A.; Gschwend, J.; Gutierrez, G.; Krause, E.; Kuehn, K.; Lin, H.; Maia, M. A. G.; March, M.; Menanteau, F.; Miquel, R.; Plazas, A. A.; Romer, A. K.; Sanchez, E.; Santiago, B.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Sobreira, F.; Suchyta, E.; Tarle, G.; Thomas, D.; Tucker, D. L.; Walker, A. R.; Wechsler, R. H.; Wester, W.; Yanny, B.

    2017-03-17

    We present Magellan/IMACS spectroscopy of the recently-discovered Milky Way satellite Eridanus II (Eri II). We identify 28 member stars in Eri II, from which we measure a systemic radial velocity of $v_{\\rm hel} = 75.6 \\pm 1.3~\\mbox{(stat.)} \\pm 2.0~\\mbox{(sys.)}~\\mathrm{km\\,s^{-1}}$ and a velocity dispersion of $6.9^{+1.2}_{-0.9}~\\mathrm{km\\,s^{-1}}$. Assuming that Eri~II is a dispersion-supported system in dynamical equilibrium, we derive a mass within the half-light radius of Eri II is $1.2^{+0.4}_{-0.3} \\times 10^{7}~\\mathrm{M_\\odot}$, indicating a mass-to-light ratio of $420^{+210}_{-140}~\\mathrm{M_\\odot}/\\mathrm{L_\\odot}$ and confirming that it is a dark matter-dominated dwarf galaxy. From the equivalent width measurements of the CaT lines of 16 red giant member stars, we derive a mean metallicity of ${\\rm [Fe/H]} = -2.38 \\pm 0.13$ and a metallicity dispersion of $\\sigma_{\\rm [Fe/H]} = 0.47 ^{+0.12}_{-0.09}$. The velocity of Eri II in the Galactic Standard of Rest frame is $v_{\\rm GSR} = -66.6~\\mathrm{km\\,s^{-1}}$, indicating that either Eri II is falling into the Milky Way potential for the first time or it has passed the apocenter of its orbit on a subsequent passage. At a Galactocentric distance of $\\sim$370 kpc, Eri II is one of the Milky Way's most distant satellites known. Additionally, we show that the bright blue stars previously suggested to be a young stellar population are not associated with Eri II. The lack of gas and recent star formation in Eri II is surprising given its mass and distance from the Milky Way, and may place constraints on models of quenching in dwarf galaxies and on the distribution of hot gas in the Milky Way halo. Furthermore, the large velocity dispersion of Eri II can be combined with the existence of a central star cluster to constrain MACHO dark matter with mass $\\gtrsim10~\\mathrm{M_\\odot}$.

  2. Local full-waveform inversion using distant data

    Science.gov (United States)

    Masson, Yder; Romanowicz, Barbara; Zhao Zheng, Allen

    2014-05-01

    Imaging remote objects in the deep Earth, such as, subducting slabs, mantle plumes, or large low shear velocity provinces and ultra low velocity zones is key for understanding Earth's structure and the geodynamical processes involved as it cools. In order to image these structures, we developed a strategy for performing regional-scale full-waveform inversions at arbitrary location inside the Earth [1]. Our approach is to confine wave propagation computations inside the region to be imaged. This local wavefield modeling is used in combination with wavefield extrapolation techniques in order to obtain synthetic seismograms at the surface of the Earth [2]. This allows us to evaluate a misfit functional and sensitivity kernels can then be computed locally using the adjoint state method [3]. The Green's functions needed for extrapolating the wavefield are computed once for all in a 3D reference Earth model using the spectral element software Specfem/3DGLOBE. We will present benchmark tests demonstrating that the proposed method allows us to image 3D localized structures - this without having to model wave propagation in the entire Earth at each iteration, which is prohibitively costly, thus improving the feasibility of accurate imaging of regional structures anywhere in the Earth using numerical methods. We will show that our method permits to account for additional data in regional inversions, that is to account for distant earthquakes that are located outside the region of the study - preliminary results for the tomography of the north American continent will be presented. [1] Masson, Yder, Paul Cupillard, Yann Capdeville, and Barbara Romanowicz. On the numerical im- plementation of time-reversal mirrors for tomographic imaging. Geophysical Journal International, 2013. [2] J. O. A. Robertsson, S. Ryan-Grigor, C. M. Sayers, and C. H. Chapman. A finite-difference injection approach to modeling seismic fluid flow monitoring. Geophysics, 65(3):896-906, 2000. [3] R

  3. Generation of heralded entanglement between distant quantum dot hole spins

    Science.gov (United States)

    Delteil, Aymeric

    Entanglement plays a central role in fundamental tests of quantum mechanics as well as in the burgeoning field of quantum information processing. Particularly in the context of quantum networks and communication, some of the major challenges are the efficient generation of entanglement between stationary (spin) and propagating (photon) qubits, the transfer of information from flying to stationary qubits, and the efficient generation of entanglement between distant stationary (spin) qubits. In this talk, I will present such experimental implementations achieved in our team with semiconductor self-assembled quantum dots.Not only are self-assembled quantum dots good single-photon emitters, but they can host an electron or a hole whose spin serves as a quantum memory, and then present spin-dependent optical selection rules leading to an efficient spin-photon quantum interface. Moreover InGaAs quantum dots grown on GaAs substrate can profit from the maturity of III-V semiconductor technology and can be embedded in semiconductor structures like photonic cavities and Schottky diodes.I will report on the realization of heralded quantum entanglement between two semiconductor quantum dot hole spins separated by more than five meters. The entanglement generation scheme relies on single photon interference of Raman scattered light from both dots. A single photon detection projects the system into a maximally entangled state. We developed a delayed two-photon interference scheme that allows for efficient verification of quantum correlations. Moreover the efficient spin-photon interface provided by self-assembled quantum dots allows us to reach an unprecedented rate of 2300 entangled spin pairs per second, which represents an improvement of four orders of magnitude as compared to prior experiments carried out in other systems.Our results extend previous demonstrations in single trapped ions or neutral atoms, in atom ensembles and nitrogen vacancy centers to the domain of

  4. Farthest Neighbor: The Distant Milky Way Satellite Eridanus II

    Science.gov (United States)

    Li, T. S.; Simon, J. D.; Drlica-Wagner, A.; Bechtol, K.; Wang, M. Y.; García-Bellido, J.; Frieman, J.; Marshall, J. L.; James, D. J.; Strigari, L.; Pace, A. B.; Balbinot, E.; Zhang, Y.; Abbott, T. M. C.; Allam, S.; Benoit-Lévy, A.; Bernstein, G. M.; Bertin, E.; Brooks, D.; Burke, D. L.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Cunha, C. E.; D’Andrea, C. B.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Eifler, T. F.; Flaugher, B.; Goldstein, D. A.; Gruen, D.; Gruendl, R. A.; Gschwend, J.; Gutierrez, G.; Krause, E.; Kuehn, K.; Lin, H.; Maia, M. A. G.; March, M.; Menanteau, F.; Miquel, R.; Plazas, A. A.; Romer, A. K.; Sanchez, E.; Santiago, B.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Sobreira, F.; Suchyta, E.; Tarle, G.; Thomas, D.; Tucker, D. L.; Walker, A. R.; Wechsler, R. H.; Wester, W.; Yanny, B.; (DES Collaboration

    2017-03-01

    We present Magellan/IMACS spectroscopy of the recently discovered Milky Way satellite Eridanus II (Eri II). We identify 28 member stars in Eri II, from which we measure a systemic radial velocity of {v}{hel}=75.6+/- 1.3 {{(stat.)}} +/- 2.0 {{(sys.)}} {km} {{{s}}}-1 and a velocity dispersion of {6.9}-0.9+1.2 {km} {{{s}}}-1. Assuming that Eri II is a dispersion-supported system in dynamical equilibrium, we derive a mass within the half-light radius of {1.2}-0.3+0.4× {10}7 {M}ȯ , indicating a mass-to-light ratio of {420}-140+210 {M}ȯ /{L}ȯ and confirming that it is a dark matter-dominated dwarf galaxy. From the equivalent width measurements of the Ca triplet lines of 16 red giant member stars, we derive a mean metallicity of [Fe/H] = ‑2.38 ± 0.13 and a metallicity dispersion of {σ }{{[Fe/H]}}={0.47}-0.09+0.12. The velocity of Eri II in the Galactic standard of rest frame is v GSR = ‑66.6 {km} {{{s}}}-1, indicating that either Eri II is falling into the Milky Way potential for the first time or that it has passed the apocenter of its orbit on a subsequent passage. At a Galactocentric distance of ∼370 kpc, Eri II is one of the Milky Way’s most distant satellites known. Additionally, we show that the bright blue stars previously suggested to be a young stellar population are not associated with Eri II. The lack of gas and recent star formation in Eri II is surprising given its mass and distance from the Milky Way, and may place constraints on models of quenching in dwarf galaxies and on the distribution of hot gas in the Milky Way halo. Furthermore, the large velocity dispersion of Eri II can be combined with the existence of a central star cluster to constrain massive compact halo object dark matter with mass ≳10 {M}ȯ . This paper includes data gathered with the 6.5 meter Magellan Telescopes located at Las Campanas Observatory, Chile.

  5. Conformational state of the MscS mechanosensitive channel in solution revealed by pulsed electron-electron double resonance (PELDOR) spectroscopy.

    Science.gov (United States)

    Pliotas, Christos; Ward, Richard; Branigan, Emma; Rasmussen, Akiko; Hagelueken, Gregor; Huang, Hexian; Black, Susan S; Booth, Ian R; Schiemann, Olav; Naismith, James H

    2012-10-02

    The heptameric mechanosensitive channel of small conductance (MscS) provides a critical function in Escherichia coli where it opens in response to increased bilayer tension. Three approaches have defined different closed and open structures of the channel, resulting in mutually incompatible models of gating. We have attached spin labels to cysteine mutants on key secondary structural elements specifically chosen to discriminate between the competing models. The resulting pulsed electron-electron double resonance (PELDOR) spectra matched predicted distance distributions for the open crystal structure of MscS. The fit for the predictions by structural models of MscS derived by other techniques was not convincing. The assignment of MscS as open in detergent by PELDOR was unexpected but is supported by two crystal structures of spin-labeled MscS. PELDOR is therefore shown to be a powerful experimental tool to interrogate the conformation of transmembrane regions of integral membrane proteins.

  6. Communication: Multipole approximations of distant pair energies in local correlation methods with pair natural orbitals

    Science.gov (United States)

    Werner, Hans-Joachim

    2016-11-01

    The accuracy of multipole approximations for distant pair energies in local second-order Møller-Plesset perturbation theory (LMP2) as introduced by Hetzer et al. [Chem. Phys. Lett. 290, 143 (1998)] is investigated for three chemical reactions involving molecules with up to 92 atoms. Various iterative and non-iterative approaches are compared, using different energy thresholds for distant pair selection. It is demonstrated that the simple non-iterative dipole-dipole approximation, which has been used in several recent pair natural orbitals (PNO)-LMP2 and PNO-LCCSD (local coupled-cluster with singles and doubles) methods, may underestimate the distant pair energies by up to 50% and can lead to significant errors in relative energies, unless very tight thresholds are used. The accuracy can be much improved by including higher multipole orders and by optimizing the distant pair amplitudes iteratively along with all other amplitudes. A new approach is presented in which very small special PNO domains for distant pairs are used in the iterative approach. This reduces the number of distant pair amplitudes by 3 orders of magnitude and keeps the additional computational effort for the iterative optimization of distant pair amplitudes minimal.

  7. Creating New Germplasm by Distant Hybridization in Stone Fruits: I. Effectsof Different Treatments on Cross Compatibility of Distant Hybridization inStone Fruits

    Institute of Scientific and Technical Information of China (English)

    YANGHong-hua; CHENXue-sen; LIYu-hui; FENGBao-chun; MUXiu-jia

    2004-01-01

    The effects of different treatments on cross compatibility in distant hybridization were studied in 69 cross combinations among 9 cultivars of stone fruits. The results showed that the setting percentage in balloon stage was obviously higher than that in early blooming stage. The differences of fruit set between positive and reverse crosses were significant. Female parent affected cross compatibility more remarkably than male parent in distant hybridization. The appropriate electrostatic field, He-Ne laser combined treatment with 60Co γ-ray and He-Ne laser could improve the pollen germination rate in vitro effectively, the fruit set percentage was higher than control, while 60Co γ-ray treatment reduced the pollen germination rate in vitro, and the fruit set percentageob tained by distant hybridization was lower than control.

  8. Creating New Germplasm by Distant Hybridization in Stone Fruits:Ⅰ.Effects of Different Treatments on Cross Compatibility of Distant Hybridization in Stone Fruits

    Institute of Scientific and Technical Information of China (English)

    YANG Hong-hua; CHEN Xue-sen; LI Yu-hui; FENG Bao-chun; MU Xiu-jia

    2004-01-01

    The effects of different treatments on cross compatibility in distant hybridization were studied in 69 cross combinations among 9 cultivars of stone fruits. The results showed that the setting percentage in balloon stage was obviously higher than that in early blooming stage. The differences of fruit set between positive and reverse crosses were significant. Female parent affected cross compatibility more remarkably than male parent in distant hybridization. The appropriate electrostatic field, He-Ne laser combined treatment with 60Co γ -ray and He-Ne laser could improve the pollen germination rate in vitro effectively, the fruit set percentage was higher than control, while 60Co γ -ray treatment reduced the pollen germination rate in vitro, and the fruit set percentage obtained by distant hybridization was lower than control.

  9. Risk Factors for Distant Metastasis in Patients with Minimally Invasive Follicular Thyroid Carcinoma.

    Directory of Open Access Journals (Sweden)

    Yu-Mi Lee

    Full Text Available Although patients with minimally invasive follicular thyroid carcinoma (MIFTC generally have an excellent prognosis, distant metastasis occurs in some patients. Risk factors for distant metastasis have been reported, none has been found to be conclusive. This study evaluated risk factors for distant metastasis, including protein markers, in patients with MIFTC.A review of patient records identified 259 patients who underwent surgery at Asan Medical Center from 1996 to 2010 and were subsequently diagnosed with MIFTC. After review of pathological slides, 120 patients with paraffin blocks suited for tissue microarrays (TMA were included in this study. Immunohistochemical stain of TMA slides was performed by protein markers; β-catenin, C-MET, CK19, estrogen receptor (ER α, ER β, HBME-1, MMP2, PPAR γ and progesterone receptor.120 patients included 28 males (23.3% and 92 females (76.7%, of mean age 41.5±10.8 years (range, 13-74 years. Eight patients (6.7% had distant metastases during follow-up. Univariate analysis showed that age (≥45 years, male sex, and extensive vascular invasion (≥4 foci were associated with distant metastasis. Multivariate regression analysis showed that extensive vascular invasion was the only independent risk factor for distant metastasis (p = 0.012. Although no protein markers on TMA analysis were directly related to distant metastasis of MIFTC, CK19 expression was more frequent in patients with than without extensive vascular invasion (p = 0.036.Extensive vascular invasion was the only independent risk factor for distant metastasis of MIFTC. No proteins markers were directly related to distant metastasis, but CK19 was associated with extensive vascular invasion.

  10. DISTANT IN-COMPANY FOREIGN LANGUAGE LEARNING INVOLVING UNIVERSITY STUDENTS-TUTORS

    Directory of Open Access Journals (Sweden)

    Alfiya Rafisovna Masalimova

    2014-01-01

    Full Text Available The peculiarities of distant in-company occupation-oriented foreign language learning technology for oil industry professionals under the conditions of business and education integration in the framework of corporate education and its implementing via Electron Corporate University is taken into consideration in this article. The technology proposed suggests university students as tutors and moderators involving in on-line forums for in-company foreign language learning of oil industry professionals. The purpose of this technology is its dual focus: On the one hand, it is directed on of enterprises experts’ foreign language competence forming, on the other hand-on students competence improving. Such online interaction between students, teachers and specialists of the company also contributes to students’ career path realization, to enterprises cultural norms accumulation, all the participants corporate culture forming. Steps and stages for its development ensuring integrity and continuity of oil industry professionals language learning are suggested and its major blocks or modules are presented and its advantages in managing, pedagogic, personal and economic aspect are revealed and presented as for company representatives so for university teachers and students.

  11. The role of plasma instabilities in the propagation of gamma-rays from distant Blazars

    Energy Technology Data Exchange (ETDEWEB)

    Saveliev, A.; Evoli, C.; Sigl, G. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2013-11-15

    The observation in the GeV band of distant blazars has been recently used to put constraints on the Extragalactic Background Light (EBL) and Extragalactic Magnetic Fields (EGMF). To support such claims one has to assume that the leptonic component of the electromagnetic cascade initiated by blazar gamma-rays is deflected away by strong enough EGMF, suppressing the signal in the Fermi window. Apart from magnetic fields, the development of such a cascade might be affected by plasma instabilities due to interactions with the ionized component of the Intergalactic Medium (IGM). In this paper we model the electromagnetic cascade through a Monte Carlo simulation in which both effects are taken into account separately, and we derive constraints on these scenarios from the combined Fermi-HESS data set. In the specific case of 1ES 0229+200 observations, we show that both explanations of the GeV flux suppression are compatible with the available data, specifically by assuming a magnetic field of B >or similar 10{sup -16} G or an IGM temperature of T

  12. Establishing and storing of deterministic quantum entanglement among three distant atomic ensembles.

    Science.gov (United States)

    Yan, Zhihui; Wu, Liang; Jia, Xiaojun; Liu, Yanhong; Deng, Ruijie; Li, Shujing; Wang, Hai; Xie, Changde; Peng, Kunchi

    2017-09-28

    It is crucial for the physical realization of quantum information networks to first establish entanglement among multiple space-separated quantum memories and then, at a user-controlled moment, to transfer the stored entanglement to quantum channels for distribution and conveyance of information. Here we present an experimental demonstration on generation, storage, and transfer of deterministic quantum entanglement among three spatially separated atomic ensembles. The off-line prepared multipartite entanglement of optical modes is mapped into three distant atomic ensembles to establish entanglement of atomic spin waves via electromagnetically induced transparency light-matter interaction. Then the stored atomic entanglement is transferred into a tripartite quadrature entangled state of light, which is space-separated and can be dynamically allocated to three quantum channels for conveying quantum information. The existence of entanglement among three released optical modes verifies that the system has the capacity to preserve multipartite entanglement. The presented protocol can be directly extended to larger quantum networks with more nodes.Continuous-variable encoding is a promising approach for quantum information and communication networks. Here, the authors show how to map entanglement from three spatial optical modes to three separated atomic samples via electromagnetically induced transparency, releasing it later on demand.

  13. Clearing the Cosmic Fog - The Most Distant Galaxy Ever Measured

    Science.gov (United States)

    2010-10-01

    distances to such faint and remote objects is an enormous challenge and can only reliably be done using spectroscopy from very large ground-based telescopes [4], by measuring the redshift of the galaxy's light. Matt Lehnert takes up the story: "After the announcement of the candidate galaxies from Hubble we did a quick calculation and were excited to find that the immense light collecting power of the VLT, when combined with the sensitivity of the infrared spectroscopic instrument, SINFONI, and a very long exposure time might just allow us to detect the extremely faint glow from one of these remote galaxies and to measure its distance." On special request to ESO's Director General they obtained telescope time on the VLT and observed a candidate galaxy called UDFy-38135539 [5] for 16 hours. After two months of very careful analysis and testing of their results, the team found that they had clearly detected the very faint glow from hydrogen at a redshift of 8.6, which makes this galaxy the most distant object ever confirmed by spectroscopy. A redshift of 8.6 corresponds to a galaxy seen just 600 million years after the Big Bang. Co-author Nicole Nesvadba (Institut d'Astrophysique Spatiale) sums up this work, "Measuring the redshift of the most distant galaxy so far is very exciting in itself, but the astrophysical implications of this detection are even more important. This is the first time we know for sure that we are looking at one of the galaxies that cleared out the fog which had filled the very early Universe." One of the surprising things about this discovery is that the glow from UDFy-38135539 seems not to be strong enough on its own to clear out the hydrogen fog. "There must be other galaxies, probably fainter and less massive nearby companions of UDFy-38135539, which also helped make the space around the galaxy transparent. Without this additional help the light from the galaxy, no matter how brilliant, would have been trapped in the surrounding hydrogen fog and we

  14. Super-distant molecular hybridization of plant seeds by ion beam-mediated gene cluster

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The N beam-mediated distant molecular hybridization between Ginkgo biloba I and watermelon was studied. The results showed that the ester gene of Ginkgo biloba L was successfully expressed in two varieties of watermelon. 3-16 and SR2-14-2, in both of which the ester quantities were measured as 17.0756 μg/g and 45.9998 μg/g respectively. Meanwhile, superoxide dismutase (SOD) activity in leaves of the watennelon expressing ester gene was increased twofold as compared to that of the control, showing that ion beam could mediate distant and/or super-distant donor gene expression in the cells of a receptor. Furthermore, the molecular nechanism of distant hybridization was analyzed.

  15. A new species of the leafhopper genus Bhatia Distant (Hemiptera: Cicadellidae: Deltocephalinae) from China.

    Science.gov (United States)

    Lu, Lin; Zhang, Yalin

    2015-01-01

    A new leafhopper species Bhatia multispinosa Lu & Zhang is described from the Emei Mountains in China. A checklist to the species of Bhatia Distant from China is provided, together with a key for their separation.

  16. Distant metastases from head and neck squamous cell carcinoma. Part III. Treatment

    NARCIS (Netherlands)

    Haigentz, Missak; Hartl, Dana M.; Silver, Carl E.; Langendijk, Johannes A.; Strojan, Primoz; Paleri, Vinidh; de Bree, Remco; Machiels, Jean-Pascal; Hamoir, Marc; Rinaldo, Alessandra; Paccagnella, Daniela; Shaha, Ashok R.; Takes, Robert P.; Ferlito, Alfio

    2012-01-01

    Distant metastases from head and neck squamous cell carcinoma (HNSCC), though rare at initial presentation, remain an important manifestation of cancer recurrence and mortality. Although generally considered incurable with a dismal prognosis despite palliative therapy, highly selected patients with

  17. Dissecting the complex environment of a distant quasar with MUSE

    CERN Document Server

    Husband, K; Stanway, E R; Lehnert, M D

    2015-01-01

    High redshift quasars can be used to trace the early growth of massive galaxies and may be triggered by galaxy-galaxy interactions. We present MUSE science verification data on one such interacting system consisting of the well-studied z=3.2 PKS1614+051 quasar, its AGN companion galaxy and bridge of material radiating in Lyalpha between the quasar and its companion. We find a total of four companion galaxies (at least two galaxies are new discoveries), three of which reside within the likely virial radius of the quasar host, suggesting that the system will evolve into a massive elliptical galaxy by the present day. The MUSE data are of sufficient quality to split the extended Lyalpha emission line into narrow velocity channels. In these the gas can be seen extending towards each of the three neighbouring galaxies suggesting that the emission-line gas originates in a gravitational interaction between the galaxies and the quasar host. The photoionization source of this gas is less clear but is probably dominate...

  18. Mechanisms for exchange of image data to support distant medical consultation.

    OpenAIRE

    Dayhoff, R. E.; Maloney, D. L.; Hirz, L.; Majurski, W. J.; Kuzmak, P. M.; Bradley, D.

    1993-01-01

    The VA has developed an integrated infrastructure to support the exchange of medical data, including images and text report data, between medical centers. This capability is expected to support teleconsulting and meet a variety of existing medical staffing and consultation needs. Consultation from distant locations requires at least the same complete integrated patient record available to onsite physicians. Several mechanisms are being explored to support distant medical consultation. Multime...

  19. Prognostic aspects of dynamic contrast-enhanced magnetic resonance imaging in synchronous distant metastatic rectal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Jing; Xu, Qing; Song, Jia-Cheng; Li, Yan; Xu, Lu-Lu; Shi, Hai-Bin [First Affiliated Hospital of Nanjing Medical University, Department of Radiology, Nanjing (China); Huang, Dong-Ya [First Affiliated Hospital of Nanjing Medical University, Department of General Surgery, Nanjing (China)

    2017-05-15

    To explore the correlations between DCE-MRI quantitative parameters and synchronous distant metastasis and the clinicopathological factors in rectal cancers. Sixty-three patients with rectal cancer (synchronous distant metastasis, n = 31; non-metastasis, n = 32) were enrolled in this study. Student's t test and ANOVA were used to compare DCE-MRI parameters (K{sup trans}, K{sub ep} and V{sub e}). The receiver operating characteristic (ROC) analysis was used to find the reasonable threshold of DCE-MRI parameters to differentiate lesions with synchronous distant metastasis from those without metastasis. The K{sup trans}, K{sub ep}, and V{sub e} value were significantly higher in the lesions with distant metastasis than in the lesions without distant metastasis (0.536 ± 0.242 vs. 0.299 ± 0.118 min{sup -1}, p < 0.001; 1.598 ± 0.477 vs. 1.341 ± 0.390 min{sup -1}, p = 0.022; and 0.324 ± 0.173 vs. 0.249 ± 0.091, p = 0.034; respectively). The K{sup trans} showed the highest AUCs of 0.788 (p < 0.001), with sensitivity of 61.29 % and specificity of 87.5 %, respectively. DCE-MRI parameters may represent a prognostic indicator for synchronous distant metastases in patients with rectal cancer. (orig.)

  20. Competition between dihydrogen bond and beryllium bond in complexes between HBeH and HArF: a huge blue shift of distant H-Ar stretch.

    Science.gov (United States)

    Li, Qingzhong; Liu, Xiaofeng; Li, Ran; Cheng, Jianbo; Li, Wenzuo

    2012-05-01

    A novel interaction mechanism between HArF and BeH(2) has been validated and characterized with quantum chemical calculations at the MP2/aug-cc-pVQZ level. They can interact through beryllium bonding formed between the positively charged Be atom in BeH(2) and the negatively charged F atom in HArF, besides through dihydrogen bonding. The former (61.3 kcal/mol) is much stronger than the latter (5.9 kcal/mol). The red shift is found for the associated H-Ar stretch in the dihydrogen bonding, whereas the big blue shift is observed for the distant H-Ar stretch in the beryllium bonding. The blue shift of the distant H-Ar stretch is affected greatly by computational methods. It is calculated to be 712 cm(-1) at the CCSD(T)/6-311++G(3df,2p) level, which appears to be the largest blue shift validated for any weakly bound complex yet. The substitution effect on the beryllium bond is similar to that on hydrogen bonds. The Kr atom makes the beryllium bond weaken and the distant blue shift decrease. The nature and properties of beryllium bond have been analyzed with natural bond orbital (NBO), atoms in molecules (AIM), and energy decomposition.

  1. First Results from the 7 Ms Chandra Deep Field-South Survey: A Good Hard Look at Growing Supermassive Black Holes in the Distant Universe

    Science.gov (United States)

    Brandt, William; Chandra Deep Fields Team

    2017-01-01

    Sensitive cosmic X-ray surveys with the Chandra, XMM-Newton, and now NuSTAR observatories have revolutionized our ability to find and study distant active galactic nuclei (AGNs), the main sites of supermassive black hole growth in the Universe. I will describe some recent discoveries about the demographics, physics, and ecology of distant AGNs coming from the deepest Chandra survey to date, the 7 Ms Chandra Deep Field-South. Some specific topics covered will include (1) robust X-ray spectral and variability characterization of the AGNs producing most of cosmic accretion power; (2) the demographics of AGNs in the first galaxies as revealed by direct detection and stacking; and (3) AGN/galaxy interactions as investigated via the host properties of X-ray AGNs. I will also briefly describe other remarkable discoveries coming from this survey; e.g., measurements of the evolving X-ray binary populations of normal and starburst galaxies.

  2. Entangling distant resonant exchange qubits via circuit quantum electrodynamics

    Science.gov (United States)

    Srinivasa, V.; Taylor, J. M.; Tahan, Charles

    2016-11-01

    We investigate a hybrid quantum system consisting of spatially separated resonant exchange qubits, defined in three-electron semiconductor triple quantum dots, that are coupled via a superconducting transmission line resonator. Drawing on methods from circuit quantum electrodynamics and Hartmann-Hahn double resonance techniques, we analyze three specific approaches for implementing resonator-mediated two-qubit entangling gates in both dispersive and resonant regimes of interaction. We calculate entangling gate fidelities as well as the rate of relaxation via phonons for resonant exchange qubits in silicon triple dots and show that such an implementation is particularly well suited to achieving the strong coupling regime. Our approach combines the favorable coherence properties of encoded spin qubits in silicon with the rapid and robust long-range entanglement provided by circuit QED systems.

  3. The determination of pair-distance distribution by double electron-electron resonance: regularization by the length of distance discretization with Monte Carlo calculations

    Science.gov (United States)

    Dzuba, Sergei A.

    2016-08-01

    Pulsed double electron-electron resonance technique (DEER, or PELDOR) is applied to study conformations and aggregation of peptides, proteins, nucleic acids, and other macromolecules. For a pair of spin labels, experimental data allows for the determination of their distance distribution function, P(r). P(r) is derived as a solution of a first-kind Fredholm integral equation, which is an ill-posed problem. Here, we suggest regularization by increasing the distance discretization length to its upper limit where numerical integration still provides agreement with experiment. This upper limit is found to be well above the lower limit for which the solution instability appears because of the ill-posed nature of the problem. For solving the integral equation, Monte Carlo trials of P(r) functions are employed; this method has an obvious advantage of the fulfillment of the non-negativity constraint for P(r). The regularization by the increasing of distance discretization length for the case of overlapping broad and narrow distributions may be employed selectively, with this length being different for different distance ranges. The approach is checked for model distance distributions and for experimental data taken from literature for doubly spin-labeled DNA and peptide antibiotics.

  4. The influence of halides in polyoxotitanate cages; dipole moment, splitting and expansion of d-orbitals and electron-electron repulsion.

    Science.gov (United States)

    Hanf, Schirin; Matthews, Peter D; Li, Ning; Luo, He-Kuan; Wright, Dominic S

    2017-01-03

    Metal-doped polyoxotitanate (M-POT) cages have been shown to be efficient single-source precursors to metal-doped titania [TiO2(M)] (state-of-the-art photocatalytic materials) as well as molecular models for the behaviour of dopant metal ions in bulk titania. Here we report the influence halide ions have on the optical and electronic properties of a series of halide-only, and cobalt halide-'doped' POT cages. In this combined experimental and computational study we show that halide ions can have several effects on the band gaps of halide-containing POT cages, influencing the dipole moment (hole-electron separation) and the structure of the valance band edge. Overall, the band gap behaviour stems from the effects of increasing orbital energy moving from F to I down Group 17, as well as crystal-field splitting of the d-orbitals, the potential effects of the Nephelauxetic influence of the halides and electron-electron repulsion.

  5. Cosmic X-ray Surveys of Distant Active Galaxies: The Demographics, Physics, and Ecology of Growing Supermassive Black Holes

    CERN Document Server

    Brandt, W N

    2015-01-01

    We review results from cosmic X-ray surveys of active galactic nuclei (AGNs) over the past ~ 15 yr that have dramatically improved our understanding of growing supermassive black holes (SMBHs) in the distant universe. First, we discuss the utility of such surveys for AGN investigations and the capabilities of the missions making these surveys, emphasizing Chandra, XMM-Newton, and NuSTAR. Second, we briefly describe the main cosmic X-ray surveys, the essential roles of complementary multiwavelength data, and how AGNs are selected from these surveys. We then review key results from these surveys on the AGN population and its evolution ("demographics"), the physical processes operating in AGNs ("physics"), and the interactions between AGNs and their environments ("ecology"). We conclude by describing some significant unresolved questions and prospects for advancing the field.

  6. Magnetization of a parabolic quantum dot in the presence of Rashba and Dresselhaus spin-orbit interactions

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, D. Sanjeev, E-mail: sanjeevchs@gmail.com; Chatterjee, Ashok [School of Physics, University of Hyderabad, Hyderabad 500046 (India); Mukhopadhyay, Soma [Department of Physics, DVR College of Engineering and Technology, Kashipur, Sangareddy Mandal, Hyderabad 502 285 (India)

    2015-05-15

    The magnetization of a parabolic quantum dot has been studied as a function of temperature and external magnetic field in the presence of Rashba, Dresselhaus Spin Orbit Interactions (SOI) and the electron-electron interactions. By the introduction of a simple and physically reasonable model potential, the problem has been solved exactly up to second order in both the SOI terms. Both the SOI found to be showing considerable effects on the magnetization of the quantum dot. The effect of electron-electron interaction on the magnetization also has been studied.

  7. rCBF to distant areas in the acute and chronic stages of unilateral cerebrovascular disease

    Energy Technology Data Exchange (ETDEWEB)

    Onoda, Toru; Tamada, Tsutomu; Gyoten, Masayuki; Imai, Shigeki; Kajihara, Yasumasa [Kawasaki Medical School, Kurashiki, Okayama (Japan). School of Medicine; Fukuda, Atsuhiro [Kawasaki Medical School, Kurashiki, Okayama (Japan). Clinical Care Center; Miyanoki, Syo [Kobe Univ. (Japan). School of Medicine

    2002-09-01

    In 14 patients with unilateral cerebrovascular disease, regional cerebral blood flow (CBF) to distant areas in the acute and chronic stages was evaluated by SPECT with {sup 123}I-IMP. In the acute stage, rCBF in distant areas was decreased in all patients. In the chronic stage, a decrease in rCBF was observed in the contralateral cerebellar hemisphere in 50% of unilateral cerebral hemispheric lesions, in the ipsilateral thalamus in 42.9% of cerebral cortical lesions, and in the ipsilateral cortex in 57.1% of subcortical lesions. The decreased rCBF in distant areas even in the chronic stage suggested the involvement of organic changes in the pathologic condition in this stage. (author)

  8. A method of real-time detection for distant moving obstacles by monocular vision

    Science.gov (United States)

    Jia, Bao-zhi; Zhu, Ming

    2013-12-01

    In this paper, we propose an approach for detection of distant moving obstacles like cars and bicycles by a monocular camera to cooperate with ultrasonic sensors in low-cost condition. We are aiming at detecting distant obstacles that move toward our autonomous navigation car in order to give alarm and keep away from them. Method of frame differencing is applied to find obstacles after compensation of camera's ego-motion. Meanwhile, each obstacle is separated from others in an independent area and given a confidence level to indicate whether it is coming closer. The results on an open dataset and our own autonomous navigation car have proved that the method is effective for detection of distant moving obstacles in real-time.

  9. Summary of IAU GA SpS5 - I. Obscured and distant clusters

    CERN Document Server

    Hanson, M M; Martins, F; Chene, A -N; Rosslowe, C; Herrero, A; Kim, H -J

    2012-01-01

    This first part of Special Session 5 explored the current status of infrared-based observations of obscured and distant stellar clusters in the Milky Way galaxy. Recent infrared surveys, either serendipitously or using targeted searches, have uncovered a rich population of young and massive clusters. However, cluster characterization is more challenging as it must be obtained often entirely in the infrared due to high line-of-sight extinction. Despite this, much is to be gained through the identification and careful analysis of these clusters, as they allow for the early evolution of massive stars to be better constrained. Further, they act as beacons delineating the Milky Way's structure and as nearby, resolved analogues to the distant unresolved massive clusters studied in distant galaxies.

  10. Breaks in gamma-ray spectra of distant blazars and transparency of the Universe

    Science.gov (United States)

    Rubtsov, G. I.; Troitsky, S. V.

    2014-11-01

    Energetic gamma rays scatter on soft background radiation when propagating through the Universe, producing electron-positron pairs (A.I. Nikishov, Sov. Phys. JETP 14, 393 (1962)). Gamma rays with energies between 100 GeV and a few TeV interact mostly with infrared background photons whose amount is poorly known experimentally but safely constrained from below by account of the contribution of observed light from known galaxies (R.C. Keenan, A.J. Barger, L.L. Cowie, and W.-H. Wang, Astrophys. J. 723, 40 (2010); arXiv: 1102.2428). The expected opacity of the intergalactic space limits the mean free path of TeV gamma rays to dozens of Megaparsecs. However, TeV photons from numerous more distant sources have been detected (S.P. Wakely and D. Horan, http://tevcat.uchicago.edu/). This might be interpreted, in each particular case, in terms of hardening of the emitted spectrum caused by presently unknown mechanisms at work in the sources (S. Archambault et al. (VERITAS and Fermi LAT Collaborations), Astrophys. J. 785, L16 (2014); arXiv: 1403.4308). Here we show that this interpretation is not supported by the analysis of the ensemble of all observed sources. In the frameworks of an infrared-background model with the lowest opacity (R.C. Gilmore, R.S. Somerville, J.R. Primack, and A. Dominguez, Mon. Not. Roy. Astron. Soc. 422, 3189 (2012); arXiv: 1104.0671), we reconstruct the emitted spectra of distant blazars and find that upward spectral breaks appear precisely at those energies where absorption effects are essential. Since these energies are very different for similar sources located at various distances, we conclude that the breaks are artefacts of the incorrect account of absorption and, therefore, the opacity of the Universe for gamma rays is overestimated even in the most conservative model. This implies that some novel physical or astrophysical phenomena should affect long-distance propagation of gamma rays. A scenario in which a part of energetic photons is

  11. Simultaneous observation of small- and large-energy-transfer electron-electron scattering in three-dimensional indium oxide thick films

    Science.gov (United States)

    Yang, Yang; Liu, Xin-Dian; Li, Zhi-Qing

    2016-05-01

    In three-dimensional (3D) disordered metals, the electron-phonon (e-ph) scattering is the sole significant inelastic process. Thus the theoretical prediction concerning the electron-electron (e\\text-e) scattering rate 1/τ_\\varphi as a function of temperature T in 3D disordered metal has not been fully tested thus far, though it was proposed 40 years ago (Schmid A., Z. Phys., 271 (1974) 251). We report here the simultaneous observation of small- and large-energy-transfer e\\text-e scattering in 3D indium oxide thick films. In the temperature region T≳100 \\text{K} , the temperature dependence of resistivity of each film obeys Bloch-Grüneisen law, indicating that the films possess degenerate-semiconductor characteristics in electrical transport property. In the low-temperature regime, 1/τ_\\varphi as a function of T for each film can not be ascribed to e-ph scattering. To quantitatively describe the temperature behavior of 1/τ_\\varphi , both the 3D small- and large-energy-transfer e\\text-e scattering processes should be considered. (The small- and large-energy-transfer e\\text-e scattering rates are proportional to T3/2 and T 2, respectively.) In addition, the experimental prefactors of T3/2 and T 2 are proportional to k_F-5/2 \\ell-3/2 and E_F-1 (k F is the Fermi wave number, ℓ is the electron elastic mean free path, and E F is the Fermi energy), respectively, which are completely consistent with the theoretical predictions. Our experimental results fully demonstrate the validity of the theoretical predictions concerning both small- and large-energy-transfer e\\text-e scattering rates.

  12. Electron transfer flavoprotein domain II orientation monitored using double electron-electron resonance between an enzymatically reduced, native FAD cofactor, and spin labels.

    Science.gov (United States)

    Swanson, Michael A; Kathirvelu, Velavan; Majtan, Tomas; Frerman, Frank E; Eaton, Gareth R; Eaton, Sandra S

    2011-03-01

    Human electron transfer flavoprotein (ETF) is a soluble mitochondrial heterodimeric flavoprotein that links fatty acid β-oxidation to the main respiratory chain. The crystal structure of human ETF bound to medium chain acyl-CoA dehydrogenase indicates that the flavin adenine dinucleotide (FAD) domain (αII) is mobile, which permits more rapid electron transfer with donors and acceptors by providing closer access to the flavin and allows ETF to accept electrons from at least 10 different flavoprotein dehydrogenases. Sequence homology is high and low-angle X-ray scattering is identical for Paracoccus denitrificans (P. denitrificans) and human ETF. To characterize the orientations of the αII domain of P. denitrificans ETF, distances between enzymatically reduced FAD and spin labels in the three structural domains were measured by double electron-electron resonance (DEER) at X- and Q-bands. An FAD to spin label distance of 2.8 ± 0.15 nm for the label in the FAD-containing αII domain (A210C) agreed with estimates from the crystal structure (3.0 nm), molecular dynamics simulations (2.7 nm), and rotamer library analysis (2.8 nm). Distances between the reduced FAD and labels in αI (A43C) were between 4.0 and 4.5 ± 0.35 nm and for βIII (A111C) the distance was 4.3 ± 0.15 nm. These values were intermediate between estimates from the crystal structure of P. denitrificans ETF and a homology model based on substrate-bound human ETF. These distances suggest that the αII domain adopts orientations in solution that are intermediate between those which are observed in the crystal structures of free ETF (closed) and ETF bound to a dehydrogenase (open).

  13. Model of training of computer science teachers by means of distant education technologies

    Directory of Open Access Journals (Sweden)

    Т А Соловьева

    2009-03-01

    Full Text Available Training of future computer science teachers in conditions of informatization of education is analyzed. Distant educational technologies (DET and traditional process of training, their advantages and disadvantages are considered, active functions of DET as the basis of the model of training by means of DET is stressed. It is shown that mixed education combining both distant ant traditional technologies takes place on the basis of the created model. Practical use of the model is shown on the example of the course «Recursion» for future computer science teachers.

  14. Distant Metastases in Head-and-Neck Squamous Cell Carcinoma Treated With Intensity-Modulated Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Yao Min, E-mail: min.yao@uhhospitals.org [Department of Radiation Oncology, University Hospitals Case Medical Center, Cleveland, OH (United States); Lu Minggen [School of Public Health, University of Nevada at Reno, Reno, NV (United States); Savvides, Panayiotis S. [Department of Medicine, University Hospitals Case Medical Center, Cleveland, OH (United States); Rezaee, Rod; Zender, Chad A.; Lavertu, Pierre [Department of Otolaryngology-Head and Neck Surgery, University Hospitals Case Medical Center, Cleveland, OH (United States); Buatti, John M. [Department of Radiation Oncology, University of Iowa, Iowa City, IA (United States); Machtay, Mitchell [Department of Radiation Oncology, University Hospitals Case Medical Center, Cleveland, OH (United States)

    2012-06-01

    Purpose: To determine the pattern and risk factors for distant metastases in head-and-neck squamous cell carcinoma (HNSCC) after curative treatment with intensity-modulated radiotherapy (IMRT). Methods and Materials: This was a retrospective study of 284 HNSCC patients treated in a single institution with IMRT. Sites included were oropharynx (125), oral cavity (70), larynx (55), hypopharynx (17), and unknown primary (17). American Joint Committee on Cancer stage distribution includes I (3), II (19), III (42), and IV (203). There were 224 males and 60 females with a median age of 57. One hundred eighty-six patients were treated with definitive IMRT and 98 postoperative IMRT. One hundred forty-nine patients also received concurrent cisplatin-based chemotherapy. Results: The median follow-up for all patients was 22.8 months (range, 0.07-77.3 months) and 29.5 months (4.23-77.3 months) for living patients. The 3-year local recurrence-free survival, regional recurrence-free survival, locoregional recurrence-free survival, distant metastasis-free survival, and overall survival were 94.6%, 96.4%, 92.5%, 84.1%, and 68.95%, respectively. There were 45 patients with distant metastasis. In multivariate analysis, distant metastasis was strongly associated with N stage (p = 0.046), T stage (p < 0.0001), and pretreatment maximum standardized uptake value of the lymph node (p = 0.006), but not associated with age, gender, disease sites, pretreatment standardized uptake value of the primary tumor, or locoregional control. The freedom from distant metastasis at 3 years was 98.1% for no factors, 88.6% for one factor, 68.3% for two factors, and 41.7% for three factors (p < 0.0001 by log-rank test). Conclusion: With advanced radiation techniques and concurrent chemotherapy, the failure pattern has changed with more patients failing distantly. The majority of patients with distant metastases had no local or regional failures, indicating that these patients might have microscopic distant

  15. Characterization of two distant double-slits by chaotic light second-order interference

    CERN Document Server

    D'Angelo, Milena; Pepe, Francesco V; Garuccio, Augusto; Tamma, Vincenzo

    2016-01-01

    We present the experimental characterization of two distant double-slit masks illuminated by chaotic light, in the absence of first-order imaging and interference. The scheme exploits second-order interference of light propagating through two indistinguishable pairs of disjoint optical paths passing through the masks of interest. The proposed technique leads to a deeper understanding of biphoton interference and coherence, and opens the way to the development of novel schemes for retrieving information on the relative position and the spatial structure of distant objects, which is of interest in remote sensing, biomedical imaging, as well as monitoring of laser ablation, when first-order imaging and interference are not feasible.

  16. Model of distant improvement of professional skill of the Ukrainian coaches

    Directory of Open Access Journals (Sweden)

    Petrova O.A.

    2012-03-01

    Full Text Available In article the conceptual model of organization and introduction of distant improvement of professional skill of coaches is developed and analyzed. Advantages of its introduction to coaches training, teachers and higher educational institutions which carry out a professional training for physical training and sports sphere are defined. It is developed the budgetary program project of distant improvement of professional skill of coaches on an example of National university of physical education and sports of Ukraine that consists of three stages: daily organizationally-adjusting session, independent telecommuting and daily final session with attestation.

  17. Explained: Why many surveys of distant galaxies miss 90% of their targets

    Science.gov (United States)

    2010-03-01

    Astronomers have long known that in many surveys of the very distant Universe, a large fraction of the total intrinsic light was not being observed. Now, thanks to an extremely deep survey using two of the four giant 8.2-metre telescopes that make up ESO's Very Large Telescope (VLT) and a unique custom-built filter, astronomers have determined that a large fraction of galaxies whose light took 10 billion years to reach us have gone undiscovered. The survey also helped uncover some of the faintest galaxies ever found at this early stage of the Universe. Astronomers frequently use the strong, characteristic "fingerprint" of light emitted by hydrogen known as the Lyman-alpha line, to probe the amount of stars formed in the very distant Universe [1]. Yet there have long been suspicions that many distant galaxies go unnoticed in these surveys. A new VLT survey demonstrates for the first time that this is exactly what is happening. Most of the Lyman-alpha light is trapped within the galaxy that emits it, and 90% of galaxies do not show up in Lyman-alpha surveys. "Astronomers always knew they were missing some fraction of the galaxies in Lyman-alpha surveys," explains Matthew Hayes, the lead author of the paper, published this week in Nature, "but for the first time we now have a measurement. The number of missed galaxies is substantial." To figure out how much of the total luminosity was missed, Hayes and his team used the FORS camera at the VLT and a custom-built narrowband filter [2] to measure this Lyman-alpha light, following the methodology of standard Lyman-alpha surveys. Then, using the new HAWK-I camera, attached to another VLT Unit Telescope, they surveyed the same area of space for light emitted at a different wavelength, also by glowing hydrogen, and known as the H-alpha line. They specifically looked at galaxies whose light has been travelling for 10 billion years (redshift 2.2 [3]), in a well-studied area of the sky, known as the GOODS-South field. "This is

  18. UltraVISTA : A VISTA Public Survey of the Distant Universe

    NARCIS (Netherlands)

    McCracken, H. J.; Milvang-Jensen, B.; Dunlop, J.; Franx, M.; Fynbo, J. P. U.; Le Fèvre, O.; Holt, J.; Caputi, K. I.; Goranova, Y.; Buitrago, F.; Emerson, J.; Freudling, W.; Herent, O.; Hudelot, P.; López-Sanjuan, C.; Magnard, F.; Muzzin, A.; Mellier, Y.; Møller, P.; Nilsson, K. K.; Sutherland, W.; Tasca, L.; Zabl, J.

    2013-01-01

    Large samples of distant galaxies covering degree-scale areas are an unparalleled source of information concerning the first sources that ionised the Universe and the origin of cosmic structures. The UltraVISTA public survey, using the unique capabilities of the VISTA telescope, aims to assemble a u

  19. UltraVISTA: A VISTA Public Survey of the Distant Universe

    NARCIS (Netherlands)

    McCracken, H. J.; Milvang-Jensen, B.; Dunlop, J.; Franx, M.; Fynbo, J. P. U.; Le Fèvre, O.; Holt, J.; Caputi, K. I.; Goranova, Y.; Buitrago, F.; Emerson, J.; Freudling, W.; Herent, O.; Hudelot, P.; López-Sanjuan, C.; Magnard, F.; Muzzin, A.; Mellier, Y.; Møller, P.; Nilsson, K. K.; Sutherland, W.; Tasca, L.; Zabl, J.

    2013-01-01

    Large samples of distant galaxies covering degree-scale areas are an unparalleled source of information concerning the first sources that ionised the Universe and the origin of cosmic structures. The UltraVISTA public survey, using the unique capabilities of the VISTA telescope, aims to assemble a u

  20. Prognosis and determinants of outcome following locoregional or distant recurrence in patients with cutaneous melanoma

    NARCIS (Netherlands)

    Francken, Anne Brecht; Accortt, Neil A.; Shaw, Helen M.; Wiener, Martin; Soong, Seng-jaw; Hoekstra, Harald J.; Thompson, John F.

    Objective: Information on prognosis for patients with cutaneous melanoma after locoregional or distant recurrence is sparse and controversial. The aim of this study was to analyze factors influencing outcome after the development of a first relapse. Methods: Information was extracted from the Sydney

  1. [Distant migration of a broken Nystrom-Szulc nail used for hip arthrodesis].

    Science.gov (United States)

    Pizio, Z; Wieczorek, M

    1994-01-01

    A series of 14 arthritic patients who underwent Dickson hip arthrodesis with the use of Nyström-Szulc nail has been reviewed. In three patients these solid nails were broken and the fragments have migrated distantly. These cases are reported.

  2. Diversity between and within: Approaches to Teaching about Distant Place in the Secondary School Curriculum

    Science.gov (United States)

    Taylor, Liz

    2014-01-01

    This study outlines some challenges of teaching about distant place and demonstrates how different strategies can influence school students' framings of diversity. The analysis is based on an interpretive case study of 13-14?year-old students learning about Japan in a UK school. Their changing representations of Japan were tracked in detail over a…

  3. Singlet aided infinite resource reduction in the comparison of distant fields

    CERN Document Server

    Bose, S; Plenio, M B

    2001-01-01

    We present a task which can be faithfully solved with finite resources only when aided by particles prepared in a particular entangled state: the singlet state. The task consists of identifying the mutual parallelity or orthogonality of weak distant magnetic fields whose absolute directions are completely unknown.

  4. ECA39 is a novel distant metastasis-related biomarker in colorectal cancer

    Institute of Scientific and Technical Information of China (English)

    Reigetsu Yoshikawa; Haruki Okamura; Yoshiro Nakano; Tomonori Morinaga; Tomoko Hashimoto-Tamaoki; Hidenori Yanagi; Chun-Shen Shen; Yoshinori Fujiwara; Masafumi Noda; Toshihiko Yagyu; Makoto Gega; Tsutomu Oshima; Takehira Yamamura

    2006-01-01

    AIM: To investigate the possible role of polysaccharide-K (PSK) -related markers in predicting distant metastasis and in the clinical outcome of colorectal cancer (CRC).METHODS: Firstly, we used protein microarrays to analyze the in vitro expression profiles of potential PSKrelated markers in the human colorectal adenocarcinoma cell line SW480, which carries a mutant p53 gene. Then,we investigated the clinical implications of these markers in the prognosis of CRC patients.RESULTS: ECA39, a direct target of c-Myc, was identified as a candidate protein affected by the anti-metastatic effects of PSK. Immunohistochemistry revealed that ECA39 was expressed at significantly higher levels in tumor tissues with distant metastases compared to those without (P < 0.00001). Positive ECA39 expression was shown to be highly reliable for the prediction of distant metastases (sensitivity: 86.7%, specificity: 90%, positive predictive value: 86.7%, negative predictive value:90%). A significantly higher cumulative 5-yr disease free survival rate was observed in the ECA39-negative patient group (77.3%) compared with the ECA39-positive patient group (25.8%) (P < 0.05).CONCLUSION: Our results suggest that ECA39 is a dominant predictive factor for distant metastasis in patients with advanced CRC and that its suppression by PSK might represent a useful application of immunotherapy as part of a program of integrated medicine.

  5. Investigation of the response of the lower ionosphere to distant powerful earthquakes

    Science.gov (United States)

    Garmash, K. P.; Gokov, A. M.; Gritchin, A. I.; Misiura, V. A.; Chernogor, L. F.

    The method of partial reflections was used in an experimental investigation of disturbances in the lower ionosphere accompanying distant powerful earthquakes. This method makes it possible to obtain vertical profiles of the parameters of the signal and of the lower ionosphere with a high time resolution. The results suggest that the observed disturbances are in fact caused by the earthquakes.

  6. Detection of distant metastases in patients with oesophageal or gastric cardia cancer: A diagnostic decision analysis

    NARCIS (Netherlands)

    E.P.M. van Vliet (Evelyn); E.W. Steyerberg (Ewout); M.J.C. Eijkemans (René); E.J. Kuipers (Ernst); P.D. Siersema (Peter)

    2007-01-01

    textabstractComputed tomography (CT) is presently a standard procedure for the detection of distant metastases in patients with oesophageal or gastric cardia cancer. We aimed to determine the additional diagnostic value of alternative staging investigations. We included 569 oesophageal or gastric

  7. Phoneme Class Based Adaptation for Mismatch Acoustic Modeling of Distant Noisy Speech (Preprint)

    Science.gov (United States)

    2012-03-01

    microphone acoustic model and distant data MFCCs. First by investigating the close talk microphone acoustic model, the English phonemes were divided...Acoustic- Phonetic Continuous Speech Corpus” Linguistic Data Consortium, Philadelphia, 1993. [5] Smith, L. I., “A Tutorial on Principal Components

  8. Diversity between and within: Approaches to Teaching about Distant Place in the Secondary School Curriculum

    Science.gov (United States)

    Taylor, Liz

    2014-01-01

    This study outlines some challenges of teaching about distant place and demonstrates how different strategies can influence school students' framings of diversity. The analysis is based on an interpretive case study of 13-14?year-old students learning about Japan in a UK school. Their changing representations of Japan were tracked in detail over a…

  9. The CfA-Rosat Survey of Distant Clusters of Galaxies

    Science.gov (United States)

    McNamara, Brian

    1998-01-01

    We (Vikhlinin, McNamara, Forman, Jones, Hornstrup, Quintana) have completed a new survey of distant clusters of galaxies, which we use to to study cluster evolution over cosmological timescales. The clusters were identified as extended X-ray sources in 650 ROSAT PSPC images of high Galactic latitude fields. Our catalog of approximately 230 extended X-ray sources covers 160 square degrees on the sky. Ours is the largest of the several ROSAT serendipitous cluster surveys in progress (e.g. SHARC, Rosati, WARPS etc.). Using V,R,I imagery obtained at several observatories, we find that greater than 90% of the X-ray sources are associated with distant clusters of galaxies. We have obtained spectroscopic redshifts for nearly 80 clusters in our catalog, and we have measured photometric redshifts for the remaining clusters. Our sample contains more than 20 clusters at z > 0.5. I will discuss the logN-logS relationship for our clusters. Because our large survey area, we are able to confirm the evolution of the most luminous distant clusters first seen in the Einstein Extended Medium Sensitivity Survey. In addition, I will discuss the relationships between optical richness, core radius, and X-ray luminosity for distant, X-ray-selected clusters.

  10. UltraVISTA : A VISTA Public Survey of the Distant Universe

    NARCIS (Netherlands)

    McCracken, H. J.; Milvang-Jensen, B.; Dunlop, J.; Franx, M.; Fynbo, J. P. U.; Le Fèvre, O.; Holt, J.; Caputi, K. I.; Goranova, Y.; Buitrago, F.; Emerson, J.; Freudling, W.; Herent, O.; Hudelot, P.; López-Sanjuan, C.; Magnard, F.; Muzzin, A.; Mellier, Y.; Møller, P.; Nilsson, K. K.; Sutherland, W.; Tasca, L.; Zabl, J.

    2013-01-01

    Large samples of distant galaxies covering degree-scale areas are an unparalleled source of information concerning the first sources that ionised the Universe and the origin of cosmic structures. The UltraVISTA public survey, using the unique capabilities of the VISTA telescope, aims to assemble a u

  11. Proposed Training Module on Goal Setting and Decision-Making Skills for Distant Learners

    Science.gov (United States)

    Ibrahim, Aminu Kazeem; Tanglang, Nebath

    2015-01-01

    Inappropriate goal setting and decision-making skills are threat to distant learners' completion of academic programme, development and social well-being. This was realised following two related studies carried out by the authors of this write-up in addition to facts from reviewed literatures as one of the factors responsible for low retention and…

  12. Modern imaging techniques for preoperative detection of distant metastases in gastric cancer

    NARCIS (Netherlands)

    Kwee, Robert M.; Kwee, Thomas C.

    2015-01-01

    A substantial portion of patients with newly diagnosed gastric cancer has distant metastases (M1 disease). These patients have a very poor prognosis and it is generally accepted that they should be treated with noncurative intent. Because it dramatically changes prognosis and treatment plans, it is

  13. The fates of Solar system analogues with one additional distant planet

    CERN Document Server

    Veras, Dimitri

    2016-01-01

    The potential existence of a distant planet ("Planet Nine") in the Solar system has prompted a re-think about the evolution of planetary systems. As the Sun transitions from a main sequence star into a white dwarf, Jupiter, Saturn, Uranus and Neptune are currently assumed to survive in expanded but otherwise unchanged orbits. However, a sufficiently-distant and sufficiently-massive extra planet would alter this quiescent end scenario through the combined effects of Solar giant branch mass loss and Galactic tides. Here, I estimate bounds for the mass and orbit of a distant extra planet that would incite future instability in systems with a Sun-like star and giant planets with masses and orbits equivalent to those of Jupiter, Saturn, Uranus and Neptune. I find that this boundary is diffuse and strongly dependent on each of the distant planet's orbital parameters. Nevertheless, I claim that instability occurs more often than not when the planet is as massive as Jupiter and harbours a semimajor axis exceeding abo...

  14. EDisCS -- the ESO Distant Cluster Survey -- Sample Definition and Optical Photometry

    CERN Document Server

    White, S D M; Simard, L; Rudnick, G; De Lucia, G; Aragón-Salamanca, A; Bender, R; Best, P; Bremer, M; Charlot, S; Dalcanton, J; Dantel, M; Desai, V; Fort, B; Halliday, C; Jablonka, P; Kauffmann, G; Mellier, Y; Milvang-Jensen, B; Pellò, R; Poggianti, B M; Poirier, S; Rottgering, H; Saglia, R; Schneider, P; Zaritsky, D

    2005-01-01

    We present the ESO Distant Cluster Survey (EDisCS) a survey of 20 fields containing distant galaxy clusters with redshifts ranging from 0.4 to almost 1.0. Candidate clusters were chosen from among the brightest objects identified in the Las Campanas Distant Cluster Survey, half with estimated redshift z_est~0.5 and half with z_est~0.8. They were confirmed by identifying red sequences in moderately deep two colour data from VLT/FORS2. For confirmed candidates we have assembled deep three-band optical photometry using VLT/FORS2, deep near-infrared photometry in one or two bands using NTT/SOFI, deep optical spectroscopy using VLT/FORS2, wide field imaging in two or three bands using the ESO Wide Field Imager, and HST/ACS mosaic images for 10 of the most distant clusters. This first paper presents our sample and the VLT photometry we have obtained. We present images, colour-magnitude diagrams and richness estimates for our clusters, as well as giving redshifts and positions for the brightest cluster members. Subs...

  15. Threat by association : Do distant intergroup threats carry-over into local intolerance?

    NARCIS (Netherlands)

    Bouman, Thijs; van Zomeren, Martijn; Otten, Sabine

    2014-01-01

    Individuals are often confronted with intergroup threats, yet many of these threats emanate from distant groups that most individuals are unlikely to encounter in their local environment. An important yet unanswered question is whether reactions to those threats, such as intolerance towards the thre

  16. Computer-Mediated Communication with Distant Friends: Relations with Adjustment during Students' First Semester in College

    Science.gov (United States)

    Ranney, John D.; Troop-Gordon, Wendy

    2012-01-01

    Because of recent technological innovations, college freshmen can readily communicate with friends who they see infrequently (e.g., friends from home). The current study addressed whether computer-mediated communication with these distant friends can compensate for a lack of high-quality on-campus friendships during students' first semester of…

  17. Prognosis and determinants of outcome following locoregional or distant recurrence in patients with cutaneous melanoma

    NARCIS (Netherlands)

    Francken, Anne Brecht; Accortt, Neil A.; Shaw, Helen M.; Wiener, Martin; Soong, Seng-jaw; Hoekstra, Harald J.; Thompson, John F.

    2008-01-01

    Objective: Information on prognosis for patients with cutaneous melanoma after locoregional or distant recurrence is sparse and controversial. The aim of this study was to analyze factors influencing outcome after the development of a first relapse. Methods: Information was extracted from the Sydney

  18. Augmentation of blood circulation to the fingers by warming distant body areas

    Science.gov (United States)

    Koscheyev, V. S.; Leon, G. R.; Paul, S.; Tranchida, D.; Linder, I. V.

    2000-01-01

    Future activities in space will require greater periods of time in extreme environments in which the body periphery will be vulnerable to chilling. Maintaining the hands and fingers in comfortable conditions enhances finger flexibility and dexterity, and thus effects better work performance. We have evaluated the efficacy of promoting heat transfer and release by the extremities by increasing the blood flow to the periphery from more distant parts of the body. The experimental garment paradigm developed by the investigators was used to manipulate the temperature of different body areas. Six subjects, two females and four males, were evaluated in a stage-1 baseline condition, with the inlet temperature of the circulating water in the liquid cooling/warming garment (LCWG) at 33 degrees C. At stage 2 the total LCWG water inlet temperature was cooled to 8 degrees C, and at stage 3 the inlet water temperature in specific segments of the LCWG was warmed (according to protocol) to 45 degrees C, while the inlet temperature in the rest of the LCWG was maintained at 8 degrees C. The following four body-area-warming conditions were studied in separate sessions: (1) head, (2) upper torso/arm, (3) upper torso/arm/head, and (4) legs/feet. Skin temperature, heat flux and blood perfusion of the fingers, and subjective perception of thermal sensations and overall physical comfort were assessed. Finger temperature (T(fing)) analyses showed a statistically significant condition x stage interaction. Post-hoc comparisons (T(fing)) indicated that at stage 3, the upper torso/arm/head warming condition was significantly different from the head, upper torso/arm and legs/feet conditions, showing an increase in T(fing). There was a significant increase in blood perfusion in the fingers at stage 3 in all conditions. Subjective perception of hand warmth, and overall physical comfort level significantly increased in the stage 3 upper torso/arm/head condition. The findings indicate that

  19. [Lymph node and distant metastases of thyroid gland cancer. Metastases in the thyroid glands].

    Science.gov (United States)

    Schmid, K W

    2015-11-01

    The different biological features of the various major entities of thyroid cancer, e.g. papillary, follicular, poorly differentiated, anaplastic and medullary, depend to a large extent on their different metastatic spread. Papillary thyroid cancer (PTC) has a propensity for cervical lymphatic spread that occurs in 20-50 % of patients whereas distant metastasis occurs in thyroid cancer (FTC) has a marked propensity for vascular but not lymphatic invasion and 10-20 % of FTC develop distant metastases. At the time of diagnosis approximately one third of medullary thyroid cancer (MTC) cases show lymph node metastases, in 10-15 % distant metastases and 25 % develop metastases during the course of the disease. Poorly differentiated (PDTC) and anaplastic thyroid cancer (ATC) spread via both lymphatic and vascular invasion. Thus distant metastases are relatively uncommon in DTC and when they occur, long-term stable disease is the typical clinical course. The major sites of distant metastases are the lungs and bone. Metastases to the brain, breasts, liver, kidneys, muscle and skin are relatively rare or even rare. The thyroid gland itself can be a site of metastases from a variety of other tumors. In autopsy series of patients with disseminated cancer disease, metastases to the thyroid gland were found in up to 10 % of cases. Metastases from other primary tumors to the thyroid gland have been reported in 1.4-3 % of patients who have surgery for suspected cancer of the thyroid gland. The most common primary cancers that metastasize to the thyroid gland are renal cell (48.1 %), colorectal (10.4 %), lung (8.3 %) and breast cancer (7.8 %) and surprisingly often sarcomas (4.0 %).

  20. Distant Neighbors

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    China strives to establish a closer rapport with Latin American countries Latin America is in with China. Chinese Vice President Xi Jinping’s recent tour to five Latin American Icountries is the latest testament to their growing relations. From February 8 to February 22, Xi traveled to Mexico Jamaica, Colombia

  1. One shot, one kill: the forces delivered by archer fish shots to distant targets.

    Science.gov (United States)

    Burnette, Morgan F; Ashley-Ross, Miriam A

    2015-10-01

    Archer fishes are skillful hunters of terrestrial prey, firing jets of water that dislodge insects perched on overhead vegetation. In the current investigation, we sought an answer to the question: are distant targets impractical foraging choices? Targets far from the shooter might not be hit with sufficient force to cause them to fall. However, observations from other investigators show that archer fish fire streams of water that travel in a non-ballistic fashion, which is thought to keep on-target forces high, even to targets that are several body lengths distant from the fish. We presented targets at different distances and investigated three aspects of foraging behavior: (i) on-target forces, (ii) shot velocity, (iii) a two-target choice assay to determine if fish would show any preference for downing closer targets or more distant targets. In general, shots from our fish (Toxotes chatareus) showed a mild decrease (less than 15% on average) in on-target forces at our most distant target offered (5.8 body lengths) with respect to the closest target offered (2.3 body lengths). One individual in our investigation showed slightly, but significantly, greater on-target forces as target distance increased. Forces on the furthest targets offered were found to double that of attachment forces for 200mg insects, even for individuals whose on-target forces showed mild decreases with increases in target distance. High-speed video analysis of jet impact with the target revealed that the shot was traveling in a non-ballistic manner, even to our most distant target offered, corroborating previous suppositions that on-target forces should remain high. Fish were able to accomplish this without large changes to shot velocity, but we did find evidence that the water jets appeared to differ in the timing of their acceleration as target distance increased. Our two-target choice experiment revealed that fish show preference for downing the closer target first, even though impact

  2. Local and distant recurrences in rectal cancer patients are predicted by the nonspecific immune response; specific immune response has only a systemic effect - a histopathological and immunohistochemical study

    Directory of Open Access Journals (Sweden)

    Mulder-Stapel Adri

    2001-07-01

    Full Text Available Abstract Background Invasion and metastasis is a complex process governed by the interaction of genetically altered tumor cells and the immunological and inflammatory host reponse. Specific T-cells directed against tumor cells and the nonspecific inflammatory reaction due to tissue damage, cooperate against invasive tumor cells in order to prevent recurrences. Data concerning involvement of individual cell types are readily available but little is known about the coordinate interactions between both forms of immune response. Patients and methods The presence of inflammatory infiltrate and eosinophils was determined in 1530 patients with rectal adenocarcinoma from a multicenter trial. We selected 160 patients to analyze this inflammatory infiltrate in more detail using immunohistochemistry. The association with the development of local and distant relapses was determined using univariate and multivariate log rank testing. Results Patients with an extensive inflammatory infiltrate around the tumor had lower recurrence rates (3.4% versus 6.9%, p = 0.03, showing the importance of host response against tumor cells. In particular, peritumoral mast cells prevent local and distant recurrence (44% versus 15%, p = 0.007 and 86% versus 21%, p Conclusions We showed that next to properties of tumor cells, the amount and type of inflammation is also relevant in the control of rectal cancer. Knowledge of the factors involved may lead to new approaches in the management of rectal cancer.

  3. On the absence of plasma wave emissions and the magnetic field orientation in the distant magnetosheath

    Energy Technology Data Exchange (ETDEWEB)

    Coroniti, F.V.; Greenstadt, E.W.; Moses, S.L. [TRW Space and Electronics Group, Redondo Beach, CA (United States); Tsurutani, B.T.; Smith, E.J. [California Institute of Technology, Pasadena, CA (United States)

    1994-12-01

    In early September, 1983 ISEE-3 made a long traversal of the distant dawnside magnetosheath starting near x = {minus}150 R{sub E} downstream. The distant magnetosheath often contains moderately intense plasma wave emissions at frequencies from several hundred Hz to 5 kHz. However, over time scales of many days, a clear correlation exists between the occurrence of the plasma waves and the cone angle ({theta}{sub xB}) between the magnetic field and the plasma flow velocity (x-direction). For {theta}{sub xB} large (small), the plasma wave amplitudes are near background (high). Sudden (<1 minute) changes in the local magnetic field orientation produce correspondingly sudden changes in the wave amplitudes. Statistically, the wave amplitudes decrease continuously with increasing {theta}{sub xB}. 7 refs., 5 figs.

  4. Precision Measurement of The Most Distant Spectroscopically-Confirmed Supernova Ia with the Hubble Space Telescope

    CERN Document Server

    Rubin, D; Rykoff, E; Aldering, G; Amanullah, R; Barbary, K; Burns, M S; Conley, A; Connolly, N; Deustua, S; Fadeyev, V; Fakhouri, H K; Fruchter, A S; Gibbons, R A; Goldhaber, G; Goobar, A; Hsiao, E Y; Huang, X; Kowalski, M; Lidman, C; Meyers, J; Nordin, J; Perlmutter, S; Saunders, C; Spadafora, A L; Stanishev, V; Suzuki, N; Wang, L

    2012-01-01

    We report the discovery of a redshift 1.71 supernova in the GOODS North field. The Hubble Space Telescope (HST) ACS spectrum has almost negligible contamination from the host or neighboring galaxies, allowing us to confirm it as a Type Ia. A serendipitous HST WFC3 IR spectrum, taken after the supernova had faded, gives a host-galaxy redshift of 1.713 +/- 0.007 which matches the SN redshift. In addition to being the most distant SN Ia with spectroscopic confirmation, this is the most distant Ia with a precision color measurement. We present the ACS WFC and NICMOS 2 photometry and ACS and WFC3 spectroscopy. Our derived supernova distance is in agreement with the prediction of LambdaCDM.

  5. Mechanisms for exchange of image data to support distant medical consultation.

    Science.gov (United States)

    Dayhoff, R E; Maloney, D L; Hirz, L; Majurski, W J; Kuzmak, P M; Bradley, D

    1993-01-01

    The VA has developed an integrated infrastructure to support the exchange of medical data, including images and text report data, between medical centers. This capability is expected to support teleconsulting and meet a variety of existing medical staffing and consultation needs. Consultation from distant locations requires at least the same complete integrated patient record available to onsite physicians. Several mechanisms are being explored to support distant medical consultation. Multimedia extensions to the VA's electronic mail system have been developed to allow images and other data objects to be included in electronic mail messages. Another approach that has been prototyped is to extend existing local imaging networks to produce more widely distributed imaging systems. These approaches will be described and discussed.

  6. Distant skeletal muscle metastasis from intrahepatic cholangiocarcinoma presenting as Budd-Chiari syndrome

    Institute of Scientific and Technical Information of China (English)

    Oh Sung Kwon; Young Sook Park; Jong Eun Joo; Dae Won Jun; Sang Heum Kim; Mee Yeon Chung; Nam In Kim; Moon Hee Song; Han Hyo Lee; Seung Hwan Kim; Yoon Ju Jo

    2007-01-01

    Intrahepatic cholangiocarcinoma is a malignant neoplasm arising from the biliary epithelium, which frequently invades adjacent organs or metastasizes to other visceral organs such as the lungs, bones, adrenals, and brain. However, distant skeletal muscle metastasis of cholangiocarcinoma has never been described before to the best of our knowledge and, furthermore, Budd-Chiari syndrome secondary to intrahepatic cholangiocarcinoma is also extremely rare. Here we present the first case overall of distant muscle metastasis from intrahepatic cholangiocarcinoma presenting as Budd-Chiari syndrome. A 44-year-old man admitted to the hospital with complaints of abdominal distension, edema of both legs, back pain and anorexia of 30 o" duration. Computed tomography and ultrasonography-guided percutaneous muscle biopsy established intrahepatic cholangiocarcinoma with disseminated thrombosis from inferior vena cava to bilateral iliac and femoral veins, and multiple skeletal muscle metastases in bilateral buttock and erector spinal muscle.

  7. Quantum logic operations on two distant atoms trapped in two optical-fibre-connected cavities

    Institute of Scientific and Technical Information of China (English)

    Zhang Ying-Qiao; Zhang Shou; Yeon Kyu-Hwang; Yu Seong-Cho

    2011-01-01

    Based on the coupling of two distant three-level atoms in two separate optical cavities connected with two optical fibres,schemes on the generation of several two-qubit logic gates are discussed under the conditions of △ =δ -2v cos πk/2 (》) g/2 and (v~ g).Discussion and analysis of the fidelity,gate time and experimental setups show that our schemes are feasible with current optical cavity,atomic trap and optical fibre techniques.Moreover,the atom-cavityfibre coupling can be used to generate an N-qubit nonlocal entanglement and transfer quantum information among N distant atoms by arranging N atom-cavity assemblages in a line and connecting each two adjacent cavities with two optical fibres.

  8. Malignant ameloblastoma: concurrent presentation of primary and distant disease and review of the literature.

    Science.gov (United States)

    Berger, Aaron J; Son, Ji; Desai, Nikhil K

    2012-10-01

    Malignant ameloblastoma is a rare tumor of odontogenic origin with a metastatic focus. Distant metastatic disease is found most commonly in the lungs. A review of the literature shows that most cases of malignant ameloblastoma involve a disease-free period from primary tumor extirpation to the discovery of metastasis. This report describes the case of a 56-year-old man presenting with ameloblastoma of the maxilla and a solitary pulmonary metastasis concurrently. This represents a rare case in which there is a simultaneous diagnosis of primary ameloblastoma and a metastatic lesion. Appropriate workup for ameloblastoma includes surveillance for metastatic disease. Surgical resection of primary and distant disease is recommended. Chemotherapy and radiation may play a role in palliation when resection of metastatic disease is not feasible. Copyright © 2012 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  9. TIMING AND INTERSTELLAR SCATTERING OF 35 DISTANT PULSARS DISCOVERED IN THE PALFA SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Nice, D. J. [Department of Physics, Lafayette College, Easton, PA 18042 (United States); Altiere, E.; Farrington, D.; Popa, L.; Wang, Y. [Department of Physics, Bryn Mawr College, Bryn Mawr, PA 19010 (United States); Bogdanov, S.; Camilo, F. [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Cordes, J. M.; Brazier, A.; Chatterjee, S. [Astronomy Department, Cornell University, Ithaca, NY 14853 (United States); Hessels, J. W. T. [ASTRON, The Netherlands Institute for Radio Astronomy, Postbus 2, 7990-AA Dwingeloo (Netherlands); Kaspi, V. M. [Department of Physics, McGill University, Montreal, QC H3A 2T8 (Canada); Lyne, A. G.; Stappers, B. W. [Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom); Ransom, S. M. [NRAO, Charlottesville, VA 22903 (United States); Sanpa-arsa, S. [Department of Astronomy, University of Virginia, Charlottesville, VA 22903 (United States); Allen, B. [Max-Planck-Institut fuer Gravitationsphysik, D-30167 Hannover (Germany); Bhat, N. D. R. [Center for Astrophysics and Supercomputing, Swinburne University, Hawthorn, Victoria 3122 (Australia); Champion, D. J. [Max-Planck-Institut fuer Radioastronomie, D-53121 Bonn (Germany); Crawford, F. [Department of Physics and Astronomy, Franklin and Marshall College, Lancaster, PA 17604-3003 (United States); and others

    2013-07-20

    We have made extensive observations of 35 distant slow (non-recycled) pulsars discovered in the ongoing Arecibo PALFA pulsar survey. Timing observations of these pulsars over several years at Arecibo Observatory and Jodrell Bank Observatory have yielded high-precision positions and measurements of rotation properties. Despite being a relatively distant population, these pulsars have properties that mirror those of the previously known pulsar population. Many of the sources exhibit timing noise, and one underwent a small glitch. We have used multifrequency data to measure the interstellar scattering properties of these pulsars. We find scattering to be higher than predicted along some lines of sight, particularly in the Cygnus region. Finally, we present XMM-Newton and Chandra observations of the youngest and most energetic of the pulsars, J1856+0245, which has previously been associated with the GeV-TeV pulsar wind nebula HESS J1857+026.

  10. Retention of Highly Skilled Workers in Science and Technology: Distant Regional Employers’ Point of View

    Directory of Open Access Journals (Sweden)

    Catherine Beaudry

    2014-05-01

    Full Text Available This exploratory research focuses on the retention of highly skilled workers in science and technology (HSWST in the distant regions of Canada.  Indeed, the human resource shortage forces them to seek more stability in their employment relationships. Our first objective is to analyze the point of view of distant regional employers regarding their retention capacity of HSWST and the reasons behind voluntary turnover in this group of workers. Our second objective is to analyze the retention strategies and practices implemented by these employers. This study uses a qualitative approach, which is to say the case study of businesses hiring HSWST in the Lower St. Lawrence Region of Canada. Results show that employers generally think they have good retention capacity. Employers believe that departures are chiefly due to personal reasons or working conditions. In addition, employers generally have no formal or planned strategies or practices with respect to retention.

  11. Distant horizontal gene transfer is rare for multiple families of prokaryotic insertion sequences.

    Science.gov (United States)

    Wagner, Andreas; de la Chaux, Nicole

    2008-11-01

    Horizontal gene transfer in prokaryotes is rampant on short and intermediate evolutionary time scales. It poses a fundamental problem to our ability to reconstruct the evolutionary tree of life. Is it also frequent over long evolutionary distances? To address this question, we analyzed the evolution of 2,091 insertion sequences from all 20 major families in 438 completely sequenced prokaryotic genomes. Specifically, we mapped insertion sequence occurrence on a 16S rDNA tree of the genomes we analyzed, and we also constructed phylogenetic trees of the insertion sequence transposase coding sequences. We found only 30 cases of likely horizontal transfer among distantly related prokaryotic clades. Most of these horizontal transfer events are ancient. Only seven events are recent. Almost all of these transfer events occur between pairs of human pathogens or commensals. If true also for other, non-mobile DNA, the rarity of distant horizontal transfer increases the odds of reliable phylogenetic inference from sequence data.

  12. Using lunar boulders to distinguish primary from distant secondary impact craters

    Science.gov (United States)

    Bart, Gwendolyn D.; Melosh, H. J.

    2007-04-01

    A high-resolution study of 18 lunar craters, including both primary and distant secondary craters, shows that the secondary craters produce larger ejecta fragments at a given crater size than do the primary craters. The maximum boulder diameter (B) increases with crater size (D) according to the power law B = KD 2/3; for primary craters, when B and D are in meters, K is 0.29, whereas for secondary craters, we find that K is 0.46 (60% larger). Next we show that impact fracture theory predicts that secondary craters, because of their lower impact velocity, will produce larger ejecta fragments than primary craters. This result provides an opportunity for distinguishing between primary and secondary craters in high resolution planetary images. The ability to identify distant secondary craters will help constrain primary production rates of small craters and improve surface age determination of small areas based on small crater counts.

  13. A NEW DISTANT MILKY WAY GLOBULAR CLUSTER IN THE PAN-STARRS1 3π SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Laevens, Benjamin P. M.; Martin, Nicolas F. [Observatoire astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l' Université, F-67000 Strasbourg (France); Sesar, Branimir; Rix, Hans-Walter; Schlafly, Edward F. [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Bernard, Edouard J.; Ferguson, Annette M. N. [Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ (United Kingdom); Slater, Colin T.; Bell, Eric F. [Department of Astronomy, University of Michigan, 500 Church St., Ann Arbor, MI 48109 (United States); Burgett, William S.; Chambers, Kenneth C.; Denneau, Larry; Kaiser, Nicholas; Kudritzki, Rolf-Peter; Magnier, Eugene A.; Morgan, Jeffrey S.; Sweeney, William E. [Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822 (United States); Draper, Peter W.; Metcalfe, Nigel [Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom); Price, Paul A., E-mail: benjamin.laevens@astro.unistra.fr [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); and others

    2014-05-01

    We present a new satellite in the outer halo of the Galaxy, the first Milky Way satellite found in the stacked photometric catalog of the Panoramic Survey Telescope and Rapid Response System 1 (Pan-STARRS1) Survey. From follow-up photometry obtained with WFI on the MPG/ESO 2.2 m telescope, we argue that the object, located at a heliocentric distance of 145 ± 17 kpc, is the most distant Milky Way globular cluster yet known. With a total magnitude of M{sub V} = –4.3 ± 0.2 and a half-light radius of 20 ± 2 pc, it shares the properties of extended globular clusters found in the outer halo of our Galaxy and the Andromeda galaxy. The discovery of this distant cluster shows that the full spatial extent of the Milky Way globular cluster system has not yet been fully explored.

  14. A new distant Milky Way globular cluster in the Pan-STARRS1 3{\\pi} survey

    CERN Document Server

    Laevens, Benjamin P M; Sesar, Branimir; Bernard, Edouard J; Rix, Hans-Walter; Slater, Colin T; Bell, Eric F; Ferguson, Annette M N; Schlafly, Edward F; Burgett, William S; Chambers, Kenneth C; Denneau, Larry; Draper, Peter W; Kaiser, Nicholas; Kudritzki, Rolf-Peter; Magnier, Eugene A; Metcalfe, Nigel; Morgan, Jeffrey S; Price, Paul A; Sweeney, William E; Tonry, John L; Wainscoat, Richard J; Waters, Christopher

    2014-01-01

    We present a new satellite in the outer halo of the Galaxy, the first Milky Way satellite found in the stacked photometric catalog of the Panoramic Survey Telescope and Rapid Response System 1 (Pan-STARRS1) Survey. From follow-up photometry obtained with WFI on the MPG/ESO 2.2m telescope, we argue that the object, located at a heliocentric distance of 145+/-17 kpc, is the most distant Milky Way globular cluster yet known. With a total magnitude of M_V=-4.3+/-0.2 and a half-light radius of 20+/-2 pc, it shares the properties of extended globular clusters found in the outer halo of our Galaxy and the Andromeda galaxy. The discovery of this distant cluster shows that the full spatial extent of the Milky Way globular cluster system has not yet been fully explored.

  15. Invasive duct carcinoma of the forearm: a rare case of distant, isolated 'carcinoma en cuirasse'.

    Science.gov (United States)

    Farahat, Ahmed; Mohamed, Samah; Vijay, Adarsh; Magdy, Nesreen; Elaffandi, Ahmed

    2015-06-17

    Cutaneous metastasis (carcinoma en cuirasse) is a condition that results from a tumor spreading via lymphatic or vascular embolization, direct implant during surgery or skin involvement by contiguity. Contralateral distant cutaneous breast cancer has never been reported before and hence, the nature and management of such rare cases remains challenging. We aim to present a case of left-sided 'distant' cutaneous metastatic invasive duct carcinoma affecting the distal upper extremity (contralateral side) two and half years (disease-free) following treatment for right breast cancer (right mastectomy + chemoradiation). A complete metastatic work-up excluded the presence of any underlying disease. Clinical examination revealed a fungating, irregular ulcer that bled easily on touch involving the left forearm. The ulcer was excised totally and the raw area reconstructed using a split thickness graft. The patient had uneventful postoperative course and now remains disease-free for almost 1 year with no evidence of local recurrence.

  16. Timing and Interstellar Scattering of Thirty-five Distant Pulsars Discovered in the PALFA Survey

    CERN Document Server

    Nice, D J; Bogdanov, S; Cordes, J M; Farrington, D; Hessels, J W T; Kaspi, V M; Lyne, A G; Popa, L; Ransom, S M; Sanpa-arsa, S; Stappers, B W; Wang, Y; Allen, B; Bhat, N D R; Brazier, A; Camilo, F; Champion, D J; Chatterjee, S; Crawford, F; Deneva, J S; Desvignes, G; Freire, P C C; Jenet, F A; Knispel, B; Lazarus, P; Lee, K J; van Leeuwen, J; Lorimer, D R; Lynch, R; McLaughlin, M A; Scholz, P; Siemens, X; Stairs, I H; Stovall, K; Venkataraman, A; Zhu, W

    2013-01-01

    We have made extensive observations of 35 distant slow (non-recycled) pulsars discovered in the ongoing Arecibo PALFA pulsar survey. Timing observations of these pulsars over several years at Arecibo Observatory and Jodrell Bank Observatory have yielded high-precision positions and measurements of rotation properties. Despite being a relatively distant population, the properties of these pulsars mirror those of the previously known pulsar population. Many of the sources exhibit timing noise, and one underwent a small glitch. We have used multifrequency data to measure the interstellar scattering properties of these pulsars. We find scattering to be higher than predicted along some lines of sight, particularly in the Cygnus region. Lastly, we present XMM-Newton and Chandra observations of the youngest and most energetic of the pulsars, J1856+0245, which has previously been associated with the GeV-TeV pulsar wind nebula HESS J1857+026.

  17. SALT2: using distant supernovae to improve the use of Type Ia supernovae as distance indicators

    CERN Document Server

    Guy, J; Baumont, S; Hardin, D; Pain, R; Regnault, N; Basa, S; Carlberg, R G; Conley, A; Fabbro, S; Fouchez, D; Hook, I M; Howell, D A; Perrett, K; Pritchet, C J; Rich, J; Sullivan, M; Antilogus, P; Aubourg, E; Bazin, G; Bronder, J; Filiol, M; Palanque-Delabrouille, Nathalie; Ripoche, P; Ruhlmann-Kleider, V

    2007-01-01

    We present an empirical model of Type Ia supernovae spectro-photometric evolution with time. The model is built using a large data set including light-curves and spectra of both nearby and distant supernovae, the latter being observed by the SNLS collaboration. We derive the average spectral sequence of Type Ia supernovae and their main variability components including a color variation law. The model allows us to measure distance moduli in the spectral range 2500-8000 A with calculable uncertainties, including those arising from variability of spectral features. Thanks to the use of high-redshift SNe to model the rest-frame UV spectral energy distribution, we are able to derive improved distance estimates for SNe Ia in the redshift range 0.8distant Type Ia supernovae.

  18. Threat by association: do distant intergroup threats carry-over into local intolerance?

    Science.gov (United States)

    Bouman, Thijs; van Zomeren, Martijn; Otten, Sabine

    2014-09-01

    Individuals are often confronted with intergroup threats, yet many of these threats emanate from distant groups that most individuals are unlikely to encounter in their local environment. An important yet unanswered question is whether reactions to those threats, such as intolerance towards the threatening group, carry over to other groups that individuals actually do encounter in their local environment (e.g., immigrants). The main goal of our studies was to experimentally identify this carry-over effect of intergroup threat. Specifically, we hypothesized that (by definition relatively abstract) symbolic threats (e.g., threats to the ingroup's worldview) have an especially strong carry-over potential because those threats can be easily attributed to other outgroups. We tested these predictions in one correlational and two experimental studies. The results of all three studies confirmed our hypothesis that particularly distant symbolic threats were predictive of intolerance towards local outgroups.

  19. ChIP-seq Mapping of Distant-Acting Enhancers and Their In Vivo Activities

    Energy Technology Data Exchange (ETDEWEB)

    Visel, Axel; Pennacchio, Len A.

    2011-06-01

    The genomic location and function of most distant-acting transcriptional enhancers in the human genome remains unknown We performed ChIP-seq for various transcriptional coactivator proteins (such as p300) directly from different embryonic mouse tissues, identifying thousands of binding sitesTransgenic mouse experiments show that p300 and other co-activator peaks are highly predictive of genomic location AND tissue-specific activity patterns of distant-acting enhancersMost enhancers are active only in one or very few tissues Genomic location of tissue-specific p300 peaks correlates with tissue-specific expression of nearby genes Most binding sites are conserved, but the global degree of conservation varies between tissues

  20. Solar wind-magnetosphere coupling and the distant magnetotail: ISEE-3 observations

    Energy Technology Data Exchange (ETDEWEB)

    Slavin, J.A.; Smith, E.J.; Sibeck, D.G.; Baker, D.N.; Zwickl, R.D.; Akasofu, S.I.; Lepping, R.P.

    1985-09-01

    ISEE-3 Geotail observations are used to investigate the relationship between the interplanetary magnetic field, substorm activity, and the distant magnetotail. Magnetic field and plasma observations are used to present evidence for the existence of a quasi-permanent, curved reconnection neutral line in the distant tail. The distance to the neutral line varies from absolute value of X = 120 to 140 R/sub e/ near the center of the tail to beyond absolute value of X = 200 R/sub e/ at the flanks. Downstream of the neutral line the plasma sheet magnetic field is shown to be negative and directly proportional to negative B/sub z/ in the solar wind as observed by IMP-8. V/sub x/ in the distant plasma sheet is also found to be proportional to IMF B/sub z/ with southward IMF producing the highest anti-solar flow velocities. A global dayside reconnection efficiency of 20 +- 5% is derived from the ISEE-3/IMP-8 magnetic field comparisons. Substorm activity, as measured by the AL index, produces enhanced negative B/sub z/ and tailward V/sub x/ in the distant plasma sheet in agreement with the basic predictions of the reconnection-based models of substorms. The rate of magnetic flux transfer out of the tail as a function of AL is found to be consistent with previous near-earth studies. Similarly, the mass and energy fluxes carried by plasma sheet flow down the tail are consistent with theoretical mass and energy budgets for an open magnetosphere. In summary, the ISEE-3 Geotail observations appear to provide good support for reconnection models of solar wind-magnetosphere coupling and substorm energy rates. 40 refs., 5 figs.

  1. Solar wind-magnetosphere coupling and the distant magnetotail - ISEE-3 observations

    Science.gov (United States)

    Slavin, J. A.; Smith, E. J.; Sibeck, D. G.; Baker, D. N.; Zwickl, R. D.; Akasofu, S.-I.; Lepping, R. P.

    1986-01-01

    ISEE-3 Geotail observations are used to investigate the relationship between the interplanetary magnetic field, substorm activity, and the distant magnetotail. Magnetic field and plasma observations are used to present evidence for the existence of a quasi-permanent, curved reconnection neutral line in the distant tail. The distance to the neutral line varies from absolute value of X = 120 to 140 R/sub e near the center of the tail to beyond absolute value of X = 200 R/sub e at the flanks. Downstream of the neutral line the plasma sheet magnetic field is shown to be negative and directly proportional to negative B/sub z in the solar wind as observed by IMP-8. V/sub x in the distant plasma sheet is also found to be proportional to IMF B/sub z with southward IMF producing the highest anti-solar flow velocities. A global dayside reconnection efficiency of 20 + or - 5 percent is derived from the ISEE-3/IMP-8 magnetic field comparisons. Substorm activity, as measured by the AL index, produces enhanced negative B/sub z and tailward V/sub x in the distant plasma sheet in agreement with the basic predictions of the reconnection-based models of substorms. The rate of magnetic flux transfer out of the tail as a function of AL is found to be consistent with previous near-earth studies. Similarly, the mass and energy fluxes carried by plasma sheet flow down the tail are consistent with theoretical mass and energy budgets for an open magnetosphere. In summary, the ISEE-3 Geotail observations appear to provide good support for reconnection models of solar wind-magnetosphere coupling and substorm energy rates.

  2. Solar wind-magnetosphere coupling and the distant magnetotail: ISEE-3 observations

    Science.gov (United States)

    Slavin, J. A.; Smith, E. J.; Sibeck, D. G.; Baker, D. N.; Zwickl, R. D.; Akasofu, S. I.; Lepping, R. P.

    1985-01-01

    ISEE-3 Geotail observations are used to investigate the relationship between the interplanetary magnetic field, substorm activity, and the distant magnetotail. Magnetic field and plasma observations are used to present evidence for the existence of a quasi-permanent, curved reconnection neutral line in the distant tail. The distance to the neutral line varies from absolute value of X = 120 to 140 R/sub e near the center of the tail to beyond absolute value of X = 200 R/sub e at the flanks. Downstream of the neutral line the plasma sheet magnetic field is shown to be negative and directly proportional to negative B/sub z in the solar wind as observed by IMP-8. V/sub x in the distant plasma sheet is also found to be proportional to IMF B/sub z with southward IMF producing the highest anti-solar flow velocities. A global dayside reconnection efficiency of 20 +- 5% is derived from the ISEE-3/IMP-8 magnetic field comparisons. Substorm activity, as measured by the AL index, produces enhanced negative B/sub z and tailward V/sub x in the distant plasma sheet in agreement with the basic predictions of the reconnection-based models of substorms. The rate of magnetic flux transfer out of the tail as a function of AL is found to be consistent with previous near-Earth studies. Similarly, the mass and energy fluxes carried by plasma sheet flow down the tail are consistent with theoretical mass and energy budgets for an open magnetosphere. In summary, the ISEE-3 Geotail observations appear to provide good support for reconnection models of solar wind-magnetosphere coupling and substorm energy rates.

  3. drs (Distantly Related sic) Gene Polymorphisms among emm12-Type Streptococcus pyogenes Isolates

    OpenAIRE

    Brandt, Claudia M.; Haase, Gerhard; Spellerberg, Barbara; Holland, Regina; Lütticken, Rudolf

    2003-01-01

    Twenty-eight emm12-type Streptococcus pyogenes isolates from patients with invasive and noninvasive infections or from asymptomatic carriers were genetically typed. Sequencing of drs (distantly related sic [streptococcal inhibitor of complement]) genes identified two novel alleles and revealed a polymorphism for drs similar to that of sic. No association was observed between the five different drs alleles and the five restriction patterns of the vir regulon for the isolates studied. These dat...

  4. Entanglement between Two Distant Observables of Quantum Current as the Mechanism of Radiation

    CERN Document Server

    Park, Jeong-Wan

    2016-01-01

    In this paper, it will be demonstrated that entanglement between two distant observables of quantum electron current enables electromagnetic radiation of free-electron lasers even though the amplified quadrature and the radiated quadrature are out of phase. This is supported by the previously observed sub-Poisson photon intensity fluctuations in the coherent spontaneous harmonic radiation generated by an infrared free-electron laser.

  5. Incorporating distant sequence features and radial basis function networks to identify ubiquitin conjugation sites.

    Directory of Open Access Journals (Sweden)

    Tzong-Yi Lee

    Full Text Available Ubiquitin (Ub is a small protein that consists of 76 amino acids about 8.5 kDa. In ubiquitin conjugation, the ubiquitin is majorly conjugated on the lysine residue of protein by Ub-ligating (E3 enzymes. Three major enzymes participate in ubiquitin conjugation. They are E1, E2 and E3 which are responsible for activating, conjugating and ligating ubiquitin, respectively. Ubiquitin conjugation in eukaryotes is an important mechanism of the proteasome-mediated degradation of a protein and regulating the activity of transcription factors. Motivated by the importance of ubiquitin conjugation in biological processes, this investigation develops a method, UbSite, which uses utilizes an efficient radial basis function (RBF network to identify protein ubiquitin conjugation (ubiquitylation sites. This work not only investigates the amino acid composition but also the structural characteristics, physicochemical properties, and evolutionary information of amino acids around ubiquitylation (Ub sites. With reference to the pathway of ubiquitin conjugation, the substrate sites for E3 recognition, which are distant from ubiquitylation sites, are investigated. The measurement of F-score in a large window size (-20∼+20 revealed a statistically significant amino acid composition and position-specific scoring matrix (evolutionary information, which are mainly located distant from Ub sites. The distant information can be used effectively to differentiate Ub sites from non-Ub sites. As determined by five-fold cross-validation, the model that was trained using the combination of amino acid composition and evolutionary information performs best in identifying ubiquitin conjugation sites. The prediction sensitivity, specificity, and accuracy are 65.5%, 74.8%, and 74.5%, respectively. Although the amino acid sequences around the ubiquitin conjugation sites do not contain conserved motifs, the cross-validation result indicates that the integration of distant sequence

  6. Distant Cutaneous Metastases of Prostate Cancer: A Report of 2 Cases.

    Science.gov (United States)

    Rodríguez-Lojo, R; Castiñeiras, I; Rey-Sanjurjo, J L; Fernández-Díaz, M L

    2016-09-01

    Cutaneous metastases of prostate cancer are extremely rare. We present 2 cases of distant cutaneous metastases at atypical locations of prostate adenocarcinoma, and highlight the value of 2 immunohistochemical stains-prostatic acid phosphatase and prostate-specific membrane antigen-that can aid diagnosis, particularly in cases with negative staining for prostate-specific antigen. Copyright © 2016 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

  7. Incorporating distant sequence features and radial basis function networks to identify ubiquitin conjugation sites.

    Science.gov (United States)

    Lee, Tzong-Yi; Chen, Shu-An; Hung, Hsin-Yi; Ou, Yu-Yen

    2011-03-09

    Ubiquitin (Ub) is a small protein that consists of 76 amino acids about 8.5 kDa. In ubiquitin conjugation, the ubiquitin is majorly conjugated on the lysine residue of protein by Ub-ligating (E3) enzymes. Three major enzymes participate in ubiquitin conjugation. They are E1, E2 and E3 which are responsible for activating, conjugating and ligating ubiquitin, respectively. Ubiquitin conjugation in eukaryotes is an important mechanism of the proteasome-mediated degradation of a protein and regulating the activity of transcription factors. Motivated by the importance of ubiquitin conjugation in biological processes, this investigation develops a method, UbSite, which uses utilizes an efficient radial basis function (RBF) network to identify protein ubiquitin conjugation (ubiquitylation) sites. This work not only investigates the amino acid composition but also the structural characteristics, physicochemical properties, and evolutionary information of amino acids around ubiquitylation (Ub) sites. With reference to the pathway of ubiquitin conjugation, the substrate sites for E3 recognition, which are distant from ubiquitylation sites, are investigated. The measurement of F-score in a large window size (-20∼+20) revealed a statistically significant amino acid composition and position-specific scoring matrix (evolutionary information), which are mainly located distant from Ub sites. The distant information can be used effectively to differentiate Ub sites from non-Ub sites. As determined by five-fold cross-validation, the model that was trained using the combination of amino acid composition and evolutionary information performs best in identifying ubiquitin conjugation sites. The prediction sensitivity, specificity, and accuracy are 65.5%, 74.8%, and 74.5%, respectively. Although the amino acid sequences around the ubiquitin conjugation sites do not contain conserved motifs, the cross-validation result indicates that the integration of distant sequence features of Ub

  8. Groundwater seepage landscapes from distant and local sources in experiments and on Mars

    Science.gov (United States)

    Marra, W. A.; McLelland, S. J.; Parsons, D. R.; Murphy, B. J.; Hauber, E.; Kleinhans, M. G.

    2015-08-01

    Valleys with theater-shaped heads can form due to the seepage of groundwater and as a result of knickpoint (waterfall) erosion generated by overland flow. This ambiguity in the mechanism of formation hampers the interpretation of such valleys on Mars, particularly since there is limited knowledge of material properties. Moreover, the hydrological implications of a groundwater or surface water origin are important for our understanding of the evolution of surface features on Mars, and a quantification of valley morphologies at the landscape scale may provide diagnostic insights on the formative hydrological conditions. However, flow patterns and the resulting landscapes produced by different sources of groundwater are poorly understood. We aim to improve the understanding of the formation of entire valley landscapes through seepage processes from different groundwater sources that will provide a framework of landscape metrics for the interpretation of such systems. We study groundwater seepage from a distant source of groundwater and from infiltration of local precipitation in a series of sandbox experiments and combine our results with previous experiments and observations of the Martian surface. Key results are that groundwater flow piracy acts on valleys fed by a distant groundwater source and results in a sparsely dissected landscape of many small and a few large valleys. In contrast, valleys fed by a local groundwater source, i.e., nearby infiltration, result in a densely dissected landscape. In addition, valleys fed by a distant groundwater source grow towards that source, while valleys with a local source grow in a broad range of directions and have a strong tendency to bifurcate, particularly on flatter surfaces. We consider these results with respect to two Martian cases: Louros Valles shows properties of seepage by a local source of groundwater and Nirgal Vallis shows evidence of a distant source, which we interpret as groundwater flow from Tharsis.

  9. Searching for distant blazars with GLAST and the Large Millimeter Telescope

    Directory of Open Access Journals (Sweden)

    Alberto Carramiñana

    2008-01-01

    Full Text Available El Gran Telescopio Milimétrico estudiará el universo a altos corrimientos al rojo, incluyendo la formación de las primeras galaxias masivas y sus núcleos activos. El GTM puede ser usado en conjunto con GLAST en la búsqueda de los blazares más distantes para explorar la época de formación de los primeros hoyos negros.

  10. Immunohistochemical markers of distant metastasis in laryngeal and hypopharyngeal squamous cell carcinomas.

    Science.gov (United States)

    Rodrigo, Juan P; Martínez, Patricia; Allonca, Eva; Alonso-Durán, Laura; Suárez, Carlos; Astudillo, Aurora; García-Pedrero, Juana María

    2014-03-01

    Metastasis remains a major cause of mortality in head and neck squamous cell carcinoma (HNSCC). Current clinicopathological features have shown limited predictability for the risk of distant metastasis in individual patients, and therefore more accurate and reliable markers are needed. The aim of this study was to investigate the ability of various molecular markers present in primary tumors to predict the risk of developing distant metastasis. Restrictive clinical criteria were applied for patient selection in order to carry out a case-control study with comparable clinical features on a group-wide basis and a similar risk of metastasis. All patients were surgically treated (with postoperative radiotherapy when appropriate) and classified as stage IV disease. Immunohistochemical analysis was performed for a panel of proteins known to participate in cellular processes relevant to metastatic dissemination (E-cadherin, annexin A2, cortactin, FAK, EGFR, p53, and p-AKT). Results showed that the loss of E-cadherin expression was significantly correlated with the risk of distant metastasis (P = 0.002; log-rank test), while the loss of annexin A2 expression was nearly statistically significant (P = 0.06). None of the other protein markers assessed were associated with the development of distant metastasis. Therefore, according to our data the loss of epithelial adhesion seems to play a central role in the development of metastasis in HNSCC, and more importantly, immunohistochemical assessment of key proteins involved in cell adhesion regulation, such as E-cadherin could represent a useful tool to evaluate easily and routinely the metastatic potential of these carcinomas.

  11. Bidirectional electron anisotropies in the distant tail - ISEE 3 observations of polar rain

    Science.gov (United States)

    Baker, D. N.; Bame, S. J.; Feldman, W. C.; Gosling, J. T.; Zwickl, R. D.; Slavin, J. A.; Smith, E. J.

    1987-01-01

    A detailed observational treatment of bidirectional electrons (50 approx. 500 eV) in the distant magnetotail (or greater than or equal to 100 R sub E) is presented. It is found that electrons in this energy range commonly exhibit strong, field aligned anisotropies in the tail lobes. Because of large tail motions, the ISEE-3 data provide extensive sampling of both the north and south lobes in rapid succession, demonstrating directly the strong asymetries that exist between the north and south lobes at any one time. The bidirectional fluxes are found to occur predominantly in the lobe directy connected to the sunward IMF in the open magnetosphere model (north lobe for away sectors and south lobe for toward sectors). Electron anisotropy and magnetic field data are presented which show the transition from unidirectional (sheath) electron populations to bidirectional (lobe) populations. Taken together, the present evidence suggests that the bidirectional electrons that we observe in the distant tail are closely related to the Polar rain electrons observed previously at lower altitudes. Furthermore, these data provide strong evidence that the distant tail is comprised largely of open magnetic field lines in contra distinction to some recently advanced models.

  12. Observations of bidirectional electrons in the distant tail lobes: GEOTAIL results

    Science.gov (United States)

    Baker, D. N.; Nishida, A.; Mukai, T.; Yamamoto, T.; Saito, Y.; Matsuno, Y.; Kokubun, S.; Pulkkinen, T. I.

    ISEE-3 demonstrated the relatively frequent occurrence of low-energy (50 ∼ 500 eV) electron flux enhancements within the distant magnetotail lobes. These electrons were found to be “bidirectional” in the sense that intensities were highest parallel (and antiparallel) to the lobe magnetic field lines. It was concluded that these electrons must enter the tail lobes along open field lines at the distant magnetopause and that this population would constitute the source for polar rain electrons at low altitudes in the polar cap regions. Similar plasma electron features have been found using the Low Energy Particle (LEP) sensor system onboard the GEOTAIL spacecraft. Remarkably close correspondences of low-energy (≲ 2 keV) ion tailward flow enhancements are found to occur when bidirectional electron fluxes suddenly intensify. Such ion plasma measurements were not available with ISEE-3 and, thus, a new aspect of solar wind entry and overall plasma dynamics is revealed by these GEOTAIL measurements in the distant tail. Other ISTP data (e.g., IMP-8 and CANOPUS) are used to analyze selected periods.

  13. Bidirectional electron anisotropies in the distant tail: ISEE-3 observations of polar rain

    Energy Technology Data Exchange (ETDEWEB)

    Baker, D.N.; Bame, S.J.; Feldman, W.C.; Gosling, J.T.; Zwickl, R.D.; Slavin, J.A.; Smith, E.J.

    1985-01-01

    A detailed observational treatment of bidirectional electrons (50 approx.500 eV) in the distant magnetotail (r greater than or equal to 100 R/sub E/) is presented. It is found that electrons in this energy range commonly exhibit strong, field-aligned anisotropies in the tail lobes. Because of large tail motions, the ISEE-3 data provide extensive sampling of both the north and south lobes in rapid succession, demonstrating directly the strong asymmetries that exist between the north and south lobes at any one time. The bidirectional fluxes are found to occur predominantly in the lobe directly connected to the sunward IMF in the open magnetosphere model (north lobe for away sectors and south lobe for toward sectors). Electron anisotropy and magnetic field data are presented which show the transition from unidirectional (sheath) electron populations to bidirectional (lobe) populations. Taken together, the present evidence suggests that the bidirectional electrons that we observe in the distant tail are closely related to the polar rain electrons observed previously at lower altitudes. Furthermore, these data provide strong evidence that the distant tail is comprised largely of open magnetic field lines in contradistinction to some recently advanced models.

  14. A wandering mind does not stray far from home: the value of metacognition in distant search.

    Science.gov (United States)

    Kudesia, Ravi S; Baer, Markus; Elfenbein, Hillary Anger

    2015-01-01

    When faced with a problem, how do individuals search for potential solutions? In this article, we explore the cognitive processes that lead to local search (i.e., identifying options closest to existing solutions) and distant search (i.e., identifying options of a qualitatively different nature than existing solutions). We suggest that mind wandering is likely to lead to local search because it operates by spreading activation from initial ideas to closely associated ideas. This reduces the likelihood of accessing a qualitatively different solution. However, instead of getting lost in thought, individuals can also step back and monitor their thoughts from a detached perspective. Such mindful metacognition, we suggest, is likely to lead to distant search because it redistributes activation away from initial ideas to other, less strongly associated, ideas. This hypothesis was confirmed across two studies. Thus, getting lost in thoughts is helpful when one is on the right track and needs only a local search whereas stepping back from thoughts is helpful when one needs distant search to produce a change in perspective.

  15. A wandering mind does not stray far from home: the value of metacognition in distant search.

    Directory of Open Access Journals (Sweden)

    Ravi S Kudesia

    Full Text Available When faced with a problem, how do individuals search for potential solutions? In this article, we explore the cognitive processes that lead to local search (i.e., identifying options closest to existing solutions and distant search (i.e., identifying options of a qualitatively different nature than existing solutions. We suggest that mind wandering is likely to lead to local search because it operates by spreading activation from initial ideas to closely associated ideas. This reduces the likelihood of accessing a qualitatively different solution. However, instead of getting lost in thought, individuals can also step back and monitor their thoughts from a detached perspective. Such mindful metacognition, we suggest, is likely to lead to distant search because it redistributes activation away from initial ideas to other, less strongly associated, ideas. This hypothesis was confirmed across two studies. Thus, getting lost in thoughts is helpful when one is on the right track and needs only a local search whereas stepping back from thoughts is helpful when one needs distant search to produce a change in perspective.

  16. The Evolution of the Hubble Sequence: morpho-kinematics of distant galaxies

    CERN Document Server

    Delgado-Serrano, Rodney

    2012-01-01

    The main objective of my thesis was to provide us, for the first time, with a reliable view of the distant Hubble sequence, and its evolution over the past 6 Gyr. To achieve this goal, we have created a new morphological classification method which (1) includes all the available observational data, (2) can be easily reproduced, and (3) presents a negligible subjectivity. This method allows us to study homogeneously the morphology of local and distant galaxies. The first step has been to study the evolution of galaxies using the IMAGES survey. This survey allowed us to establish the kinematic state of distant galaxies, to study the chemical evolution of galaxies over the past 8 Gyr, and to test important dynamical relations such as the Tully-Fisher relation. The information gained from kinematics is, indeed, crucial to guarantee a robust understanding of the different physical processes leading to the present day Hubble sequence. Using Integral Field Spectroscopy, we have been able to test our new morphologica...

  17. Multi-objective radiomics model for predicting distant failure in lung SBRT

    Science.gov (United States)

    Zhou, Zhiguo; Folkert, Michael; Iyengar, Puneeth; Westover, Kenneth; Zhang, Yuanyuan; Choy, Hak; Timmerman, Robert; Jiang, Steve; Wang, Jing

    2017-06-01

    Stereotactic body radiation therapy (SBRT) has demonstrated high local control rates in early stage non-small cell lung cancer patients who are not ideal surgical candidates. However, distant failure after SBRT is still common. For patients at high risk of early distant failure after SBRT treatment, additional systemic therapy may reduce the risk of distant relapse and improve overall survival. Therefore, a strategy that can correctly stratify patients at high risk of failure is needed. The field of radiomics holds great potential in predicting treatment outcomes by using high-throughput extraction of quantitative imaging features. The construction of predictive models in radiomics is typically based on a single objective such as overall accuracy or the area under the curve (AUC). However, because of imbalanced positive and negative events in the training datasets, a single objective may not be ideal to guide model construction. To overcome these limitations, we propose a multi-objective radiomics model that simultaneously considers sensitivity and specificity as objective functions. To design a more accurate and reliable model, an iterative multi-objective immune algorithm (IMIA) was proposed to optimize these objective functions. The multi-objective radiomics model is more sensitive than the single-objective model, while maintaining the same levels of specificity and AUC. The IMIA performs better than the traditional immune-inspired multi-objective algorithm.

  18. Cost of wind energy: comparing distant wind resources to local resources in the midwestern United States.

    Science.gov (United States)

    Hoppock, David C; Patiño-Echeverri, Dalia

    2010-11-15

    The best wind sites in the United States are often located far from electricity demand centers and lack transmission access. Local sites that have lower quality wind resources but do not require as much power transmission capacity are an alternative to distant wind resources. In this paper, we explore the trade-offs between developing new wind generation at local sites and installing wind farms at remote sites. We first examine the general relationship between the high capital costs required for local wind development and the relatively lower capital costs required to install a wind farm capable of generating the same electrical output at a remote site,with the results representing the maximum amount an investor should be willing to pay for transmission access. We suggest that this analysis can be used as a first step in comparing potential wind resources to meet a state renewable portfolio standard (RPS). To illustrate, we compare the cost of local wind (∼50 km from the load) to the cost of distant wind requiring new transmission (∼550-750 km from the load) to meet the Illinois RPS. We find that local, lower capacity factor wind sites are the lowest cost option for meeting the Illinois RPS if new long distance transmission is required to access distant, higher capacity factor wind resources. If higher capacity wind sites can be connected to the existing grid at minimal cost, in many cases they will have lower costs.

  19. Extracting PICO Sentences from Clinical Trial Reports using Supervised Distant Supervision.

    Science.gov (United States)

    Wallace, Byron C; Kuiper, Joël; Sharma, Aakash; Zhu, Mingxi Brian; Marshall, Iain J

    2016-01-01

    Systematic reviews underpin Evidence Based Medicine (EBM) by addressing precise clinical questions via comprehensive synthesis of all relevant published evidence. Authors of systematic reviews typically define a Population/Problem, Intervention, Comparator, and Outcome (a PICO criteria) of interest, and then retrieve, appraise and synthesize results from all reports of clinical trials that meet these criteria. Identifying PICO elements in the full-texts of trial reports is thus a critical yet time-consuming step in the systematic review process. We seek to expedite evidence synthesis by developing machine learning models to automatically extract sentences from articles relevant to PICO elements. Collecting a large corpus of training data for this task would be prohibitively expensive. Therefore, we derive distant supervision (DS) with which to train models using previously conducted reviews. DS entails heuristically deriving 'soft' labels from an available structured resource. However, we have access only to unstructured, free-text summaries of PICO elements for corresponding articles; we must derive from these the desired sentence-level annotations. To this end, we propose a novel method - supervised distant supervision (SDS) - that uses a small amount of direct supervision to better exploit a large corpus of distantly labeled instances by learning to pseudo-annotate articles using the available DS. We show that this approach tends to outperform existing methods with respect to automated PICO extraction.

  20. Do neutrophils play a role in establishing liver abscesses and distant metastases caused by Klebsiella pneumoniae?

    Science.gov (United States)

    Lin, Jung-Chung; Chang, Feng-Yee; Fung, Chang-Phone; Yeh, Kuo-Ming; Chen, Chiung-Tong; Tsai, Yu-Kuo; Siu, L Kristopher

    2010-11-30

    Serotype K1 Klebsiella pneumoniae is a major cause of liver abscesses and endophthalmitis. This study was designed to identify the role of neutrophils in the development of distant metastatic complications that were caused by serotype K1 K. pneumoniae. An in vitro cellular model was used to assess serum resistance and neutrophil-mediated killing. BALB/c mice were injected with neutrophils containing phagocytosed K. pneumoniae. Serotype K1 K. pneumoniae was significantly more resistant to serum killing, neutrophil-mediated phagocytosis and intra-cellular killing than non-K1 isolates (pneutrophils containing phagocytosed serotype K1 K. pneumoniae led to abscess formation in multiple sites including the subcutaneous tissue, lung, and liver, whereas no abscess formation was observed in mice injected with non-K1 isolates. The resistance of serotype K1 K. pneumoniae to complement- and neutrophil-mediated intracellular killing results in the dissemination of K. pneumoniae via the bloodstream. Escape from neutrophil intracellular killing may contribute to the dissemination and establishment of distant metastases. Thus, neutrophils play a role as a vehicle for helping K. pneumoniae and contributing to the establishment of liver abscess and distant metastatic complications.

  1. Plasma fibrinogen levels are correlated with postoperative distant metastasis and prognosis in esophageal squamous cell carcinoma.

    Science.gov (United States)

    Zhang, Danhong; Zhou, Xia; Bao, Wuan; Chen, Ying; Cheng, Lei; Qiu, Guoqin; Sheng, Liming; Ji, Yongling; Du, Xianghui

    2015-11-10

    This study investigated the correlation of preoperative plasma fibrinogen level with distant metastasis and prognosis in esophageal squamous cell carcinoma (ESCC). A total of 255 patients with ESCC who underwent surgery in Zhejiang cancer hospital (Hangzhou, China), between October 2006 and December 2009, were evaluated in this retrospective study. Population controls were selected from a pool of cancer-free subjects in the same region. Each patient and cancer-free people provided 3-mL pretreatment blood. Plasma fibrinogen level was measured by the Clauss method. The effects of hyperfibrinogenemia on locoregional relapse-free survival (LRFS), distant metastasis-free survival (DMFS), relapse-free survival (RFS), and overall survival (OS) were assessed using Kaplan-Meier analysis. Independent prognostic factors were identified in the multivariate Cox analysis. The proportion of hyperfibrinogenemia was higher in ESCC patients than those in controls (40.4% vs 13.6%). Subjects with hyperfibrinogenemia had a significantly higher risk of ESCC than those with normal plasma fibrinogen level (adjust OR = 4.61; 95% CI = 3.02-7.01, P fibrinogen level were independent prognostic factors of ESCC (P fibrinogen level was significantly associated with elevated risk of ESCC. Preoperative plasma fibrinogen level was a predictor of distant metastasis and independently associated with prognosis of patients with ESCC.

  2. Multiple distant origins for green sea turtles aggregating off Gorgona Island in the Colombian eastern Pacific.

    Directory of Open Access Journals (Sweden)

    Diego F Amorocho

    Full Text Available Mitochondrial DNA analyses have been useful for resolving maternal lineages and migratory behavior to foraging grounds (FG in sea turtles. However, little is known about source rookeries and haplotype composition of foraging green turtle aggregations in the southeastern Pacific. We used mitochondrial DNA control region sequences to identify the haplotype composition of 55 green turtles, Chelonia mydas, captured in foraging grounds of Gorgona National Park in the Colombian Pacific. Amplified fragments of the control region (457 bp revealed the presence of seven haplotypes, with haplotype (h and nucleotide (π diversities of h = 0.300±0.080 and π = 0.009±0.005 respectively. The most common haplotype was CMP4 observed in 83% of individuals, followed by CMP22 (5%. The genetic composition of the Gorgona foraging population primarily comprised haplotypes that have been found at eastern Pacific rookeries including Mexico and the Galapagos, as well as haplotypes of unknown stock origin that likely originated from more distant western Pacific rookeries. Mixed stock analysis suggests that the Gorgona FG population is comprised mostly of animals from the Galapagos rookery (80%. Lagrangian drifter data showed that movement of turtles along the eastern Pacific coast and eastward from distant western and central Pacific sites was possible through passive drift. Our results highlight the importance of this protected area for conservation management of green turtles recruited from distant sites along the eastern Pacific Ocean.

  3. Interpretation of distant focal accumulations revealed by bone scintigraphy using Tc-99m HMDP in patients with oral malignant tumors

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Tsuyoshi; Morita, Yasuhiko; Iwashita, Youichirou; Kawabata, Yoshihiro; Noikura, Takenori [Kagoshima Univ. (Japan). Dental School

    2000-06-01

    Focal accumulations in the skeleton were analyzed in order evaluate the usefulness of bone scintigraphy in the detection of distant skeletal metastases originating from malignant oral tumors. Of 350 patients who underwent bone scintigraphy, 62 patients who showed distant focal accumulations in the skeleton were selected. Observations were performed on 12 skeletal regions: the skull, facial bone, clavicle, rib, scapula, sternum, cervical spine, thoracic spine, lumbar spine, pelvis, upper, and lower extremities. Distant focal accumulations were classified into 3 degrees: very hot, moderately hot and warm. A diagnosis of metastatic focal accumulation was made with reference to the CT, MR, X-ray and Ga-67 images, clinical features, and laboratory data. Four of the 350 cases showed skeletal metastases (1.1%). Sixty-two of the 350 patients showed 106 distant focal accumulations, with 10 accumulations proving to be skeletal metastases. The common sites of the skeletal metastases were the lumbar spine, rib, cervical spine, and sternum. Patients with skeletal metastases had a tendency to show distant focal accumulations of very hot images in some skeletal sites, and these focal accumulations were usually accompanied by severe pain. The most common cause of distant focal accumulations except metastasis was traumatic injury. The results in the present study indicate that the distant focal accumulations accompanied by severe pain and simultaneously observed in more than one skeletal site can be interpreted as skeletal metastases. (author)

  4. Distinguishing synchronous from metachronous manifestation of distant metastases: a prognostic feature in differentiated thyroid carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Sabet, Amir [University Duisburg-Essen, Department of Nuclear Medicine, Essen (Germany); Saarland University Hospital, Department of Nuclear Medicine, Homburg (Germany); Binse, Ina; Koch, Andrea; Rosenbaum-Krumme, Sandra J. [University Duisburg-Essen, Department of Nuclear Medicine, Essen (Germany); Dogan, Semih; Biersack, Hans-Juergen [University Hospital, Department of Nuclear Medicine, Bonn (Germany); Biermann, Kim [University Hospital, Department of Nuclear Medicine, Bonn (Germany); Confessional Hospital ' ' Barmherzige Brueder' ' , Department of Radiology and Nuclear Medicine, Trier (Germany); Ezziddin, Samer [Saarland University Hospital, Department of Nuclear Medicine, Homburg (Germany); University Hospital, Department of Nuclear Medicine, Bonn (Germany)

    2017-02-15

    Distant metastasis has a negative impact on survival in differentiated thyroid carcinoma (DTC). The timing of this manifestation, however, is of unknown prognostic relevance. The aim of this retrospective study was to investigate the potential significance of discriminating synchronous versus metachronous distant metastases (SDM vs. MDM) for the outcome of patients with DTC. We retrospectively analyzed a consecutive cohort of n = 89 patients with distant metastases of DTC (43 with follicular, 46 with papillary DTC histology; mean age 52.6 ± 17.7 years) undergoing radioiodine treatment at our institution. All patients were treated with the same protocol consisting of ablative radioiodine therapy (RIT, 3.7 GBq) and one post-ablation treatment after 3 months (3.7-11.1 GBq). Further cycles of RIT were administered for recurrent, progressive or newly developed metastatic disease. We distinguished 2 types of distant metastases according to the time of manifestation: SDM (within ≤12 months after DTC diagnosis) and MDM (occurring >12 months after diagnosis). Tumor-related survival was analyzed using the Kaplan-Meier method. Uni- and multivariate analyses including the Cox proportional hazards model were performed with a significance level of p < 0.05. The mean follow-up period was 13.8 ± 1.2 years. SDM were present in 49 (55.1 %), MDM in 40 (44.9 %) patients. MDM were associated with shorter tumor-related survival (p = 0.002). 5-year and 10-year survival rates were 68.5 % and 34.8 % for MDM, and 84.3 % and 66.9 % for SDM, respectively. Within both age subgroups of <45 and ≥45 years, SDM were also linked with longer survival. No effect on tumor-related survival was found for the co-variables sex, lymph node metastases and histologic type. Distinguishing synchronous from metachronous manifestation of distant metastases may add an important prognostic feature to risk stratification in DTC, as proven metachronous appearance is associated with impaired survival. (orig.)

  5. Predictors of distant relapse in patients with FIGO stage IIB-IVA cervical cancer treated with definitive radiotherapy.

    Science.gov (United States)

    Okazawa-Sakai, Mika; Mabuchi, Seiji; Isohashi, Fumiaki; Kawashima, Atsushi; Yokoi, Eriko; Ogawa, Kazuhiko; Kimura, Tadashi

    2017-08-17

    To investigate the predictors of distant relapse in International Federation of Gynecology and Obstetrics (FIGO) stage IIB-IVA cervical cancer patients treated with definitive radiotherapy (RT). The clinical data of 219 patients with FIGO stage IIB-IVA cervical cancer treated with definitive RT between January 1997 and December 2011 were retrospectively reviewed. The cumulative distant relapse, progression-free survival (PFS) and overall survival (OS) rates were calculated using the Kaplan-Meier method and compared using the log-rank test. A Cox proportional hazards regression model was used to investigate the predictors of distant relapse in patients. Following treatment with definitive RT, 61 of the 219 (27.9%) patients developed distant relapse with median PFS and OS rates of 9.9 and 32.8 months, and estimated five-year PFS and OS rates of 4.9% and 21.3%, respectively. Multivariate analysis revealed that pelvic node metastasis, pretreatment leukocytosis and pretreatment neutrophilia were significant predictors of distant relapse. The risk of developing distant relapse was found to be associated with the number of predictors that the patients displayed: the estimated five-year distant relapse rates of the patients with no predictors, one predictor and two predictors were 20.3%, 35.5% and 88.9%, respectively. Roughly 28% of patients with FIGO stage IIB-IVA cervical cancer developed distant relapse after definitive RT. Pelvic lymph node metastasis and pretreatment leukocytosis/neutrophilia are independent predictors of distant relapse. © 2017 Japan Society of Obstetrics and Gynecology.

  6. Wolves (Canis lupus) and Dogs (Canis familiaris) Differ in Following Human Gaze Into Distant Space But Respond Similar to Their Packmates’ Gaze

    Science.gov (United States)

    Werhahn, Geraldine; Virányi, Zsófia; Barrera, Gabriela; Sommese, Andrea; Range, Friederike

    2017-01-01

    Gaze following into distant space is defined as visual co-orientation with another individual’s head direction allowing the gaze follower to gain information on its environment. Human and nonhuman animals share this basic gaze following behavior, suggested to rely on a simple reflexive mechanism and believed to be an important prerequisite for complex forms of social cognition. Pet dogs differ from other species in that they follow only communicative human gaze clearly addressed to them. However, in an earlier experiment we showed that wolves follow human gaze into distant space. Here we set out to investigate whether domestication has affected gaze following in dogs by comparing pack-living dogs and wolves raised and kept under the same conditions. In Study 1 we found that in contrast to the wolves, these dogs did not follow minimally communicative human gaze into distant space in the same test paradigm. In the observational Study 2 we found that pack-living dogs and wolves, similarly vigilant to environmental stimuli, follow the spontaneous gaze of their conspecifics similarly often. Our findings suggest that domestication did not affect the gaze following ability of dogs itself. The results raise hypotheses about which other dog skills might have been altered through domestication that may have influenced their performance in Study 1. Because following human gaze in dogs might be influenced by special evolutionary as well as developmental adaptations to interactions with humans, we suggest that comparing dogs to other animal species might be more informative when done in intraspecific social contexts. PMID:27244538

  7. BRAFV600E mutation is not a positive predictor for distant metastasis in sporadic papillary thyroid carcinoma

    Institute of Scientific and Technical Information of China (English)

    JING Fan-jing; LIANG Jun; LIANG Zhi-yong; MENG Chao; LONG Wen; LI Xiao-yi; LIN Yan-song

    2013-01-01

    Background BRAFV600E mutation is correlated with local aggressive clinicopathological features in papillary thyroid carcinoma; yet the relationship between this genetic variation and distant papillary thyroid carcinoma metastasis was unclear.This study aimed to investigate whether BRAFV600E is predictive for distant metastasis in the Chinese population.Methods One hundred and seven patients with papillary thyroid carcinoma were enrolled in this study,including 43 patients with distant metastasis and 64 patients without.Quantitative real-time polymerase chain reaction was used to detect BRAFV600E mutation,while immunohistochemistry was performed to detect vascular endothelial growth factor (VEGF) expression.The associations between distant metastasis and BRAFV600E mutation,and VEGF expression as well as local clinicopathological factors were determined.Results A total of 28.6% of the patients in the distant metastasis group harbored BRAFV600E mutation,which was significantly lower than in the without distant metastasis group (68.8%,P <0.001).BRAFV600E mutation was negatively correlated with positive VEGF expression (P=0.001).Furthermore,52.2% of the patients with distant metastasis exhibited VEGF expression,compared with 25.0% of those without.Higher levels of VEGF expression were also observed in the distant metastasis group.Tumor size,extra-thyroid invasion,and BRAFV600E mutation were independent predictors for distant metastasis according to multivariate analysis (odds ratios were 2.8,12.4,and 0.3; 95% CI 1.483-5.334,and 2.950-52.407,0.100-0.890; P=0.002,0.001,and 0.030,respectively).BRAFV600E mutation was negatively correlated with distant metastasis in adult subgroup analysis (P=0.005) but was not an independent parameter.Conclusions BRAFV600E mutation is predictive for distant metastasis in papillary thyroid carcinoma but not positively.VEGF may be involved in the pathogenesis of distant metastasis.

  8. Effect of Rashba and Dresselhaus interactions on the energy spectrum, chemical potential, addition energy and spin-splitting in a many-electron parabolic GaAs quantum dot in a magnetic field

    Science.gov (United States)

    Kumar, D. Sanjeev; Mukhopadhyay, Soma; Chatterjee, Ashok

    2016-11-01

    The effect of electron-electron interaction and the Rashba and Dresselhaus spin-orbit interactions on the electronic properties of a many-electron system in a parabolically confined quantum dot placed in an external magnetic field is studied. With a simple and physically reasonable model potential for electron-electron interaction term, the problem is solved exactly to second-order in the spin-orbit coupling constants to obtain the energy spectrum, the chemical potential, addition energy and the spin-splitting energy.

  9. A modified radiofrequency ablation approach for treating distant lymph node metastasis in two patients with late-stage cancer

    Institute of Scientific and Technical Information of China (English)

    Ru-Hai Zou; Qi-Jiong Li; Ji-Liang Qiu; Ya-Di Liao; Yun-Fei Yuan; An-Hua Li

    2013-01-01

    Patients with late-stage cancer commonly have distant lymph node metastasis;however, poor health often contraindicates surgical treatment. Although the quality of life and overal survival for these patients are low, there is neither a consensus nor a guide for treatment. Ablation technique and surrounding tissue damage are two possible reasons for limited study of radiofrequency ablation in patients with superficial distant lymph node metastasis. Here, we report two patients treated successfully with ultrasound-guided radiofrequency ablation for superficial distant lymph node metastasis. In these patients, deionized water was injected to the surrounding tissues of the lymph node to decrease heat injury. Results from these patients suggest that radiofrequency ablation may play an important role in the treatment of patients with distant lymph node metastasis.

  10. Contributions to Proceedings from the NATO Advanced Research Workshop on the Seismology of the Sun and the Distant Stars

    Science.gov (United States)

    1985-01-01

    Advanced research results on the seismology of the Sun and distant stars is presented. Topics presented include: (1) detection of global convective wave flows; (2) observation of low degree p-mode oscillations; and (3) techniques for spectral deconvolution.

  11. Nottingham prognostic index plus (NPI+) predicts risk of distant metastases in primary breast cancer.

    Science.gov (United States)

    Green, Andrew R; Soria, D; Powe, D G; Nolan, C C; Aleskandarany, M; Szász, M A; Tőkés, A M; Ball, G R; Garibaldi, J M; Rakha, E A; Kulka, J; Ellis, I O

    2016-05-01

    The Nottingham prognostic index plus (NPI+) is based on the assessment of biological class combined with established clinicopathologic prognostic variables providing improved patient outcome stratification for breast cancer superior to the traditional NPI. This study aimed to determine prognostic capability of the NPI+ in predicting risk of development of distant disease. A well-characterised series of 1073 primary early-stage BC cases treated in Nottingham and 251 cases from Budapest were immunohistochemically assessed for cytokeratin (Ck)5/6, Ck18, EGFR, oestrogen receptor (ER), progesterone receptor, HER2, HER3, HER4, Mucin 1 and p53 expression. NPI+ biological class and prognostic scores were assigned using individual algorithms for each biological class incorporating clinicopathologic parameters and investigated in terms of prediction of distant metastases-free survival (MFS). The NPI+ identified distinct prognostic groups (PG) within each molecular class which were predictive of MFS providing improved patient outcome stratification superior to the traditional NPI. NPI+ PGs, between series, were comparable in predicting patient outcome between series in luminal A, basal p53 altered and HER2+/ER+ (p > 0.01) tumours. The low-risk groups were similarly validated in luminal B, luminal N, basal p53 normal tumours (p > 0.01). Due to small patient numbers the remaining PGs could not be validated. NPI+ was additionally able to predict a higher risk of metastases at certain distant sites. This study may indicate the NPI+ as a useful tool in predicting the risk of metastases. The NPI+ provides accurate risk stratification allowing improved individualised clinical decision making for breast cancer.

  12. Localized experimental bone metastasis drives osteolysis and sensory hypersensitivity at distant non-tumor-bearing sites.

    Science.gov (United States)

    Abdelaziz, Dareen M; Stone, Laura S; Komarova, Svetlana V

    2015-08-01

    Patients with breast cancer metastasis to bone suffer from inadequate pain relief. Animal models provide increased understanding of cancer-induced bone and sensory alterations. The objective of this study was to investigate the measures of pain at distant non-tumor-bearing sites in animals with localized bone metastasis. Immunocompetent BALB/c mice are injected intra-tibially with murine mammary carcinoma cells (4T1) or saline, and the sensitivity to mechanical and thermal stimuli in the contralateral paw was examined. In addition to previously demonstrated development of osteolysis and hypersensitivity to mechanical and thermal stimuli in the cancer-injected tibia, these animals exhibited an increase in sensory hypersensitivity in the contralateral limb. No bone lesions were evident on radiographs of the contralateral limbs. Histomorphometry detected decreased bone volume per tissue volume and increased osteoclast number in the contralateral tibia and vertebral bones of cancer-bearing animals. Neuroplasticity was examined by immunofluorescence for calcitonin gene-related peptide (CGRP) in sensory neurons and glial fibrillary acidic protein (GFAP) in lumbar spinal cords. CGRP-immunoreactivity and GFAP-immunoreactivity were significantly elevated both ipsilateral and contralateral in tumor-bearing animals. The anti-inflammatory and osteolysis-targeting drug rapamycin reduced hypersensitivity to mechanical and cold stimuli, attenuated GFAP over-expression, and lowered osteoclast number. The osteoclast-targeting drug pamidronate reduced sensitivity to cold and protected against bone loss. Localized bone cancer drives hypersensitivity, bone remodeling, and sensory neuron plasticity at sites distant from the primary tumor area. Drugs targeting these mechanisms may be useful in the treatment of pain distant from the primary tumor site.

  13. Progressive APOBEC3B mRNA expression in distant breast cancer metastases

    Science.gov (United States)

    Dalm, Simone U.; de Weerd, Vanja; Moelans, Cathy B.; ter Hoeve, Natalie; van Diest, Paul J.; Martens, John W. M.; van Deurzen, Carolien H. M.

    2017-01-01

    Background APOBEC3B was recently identified as a gain-of-function enzymatic source of mutagenesis, which may offer novel therapeutic options with molecules that specifically target this enzyme. In primary breast cancer, APOBEC3B mRNA is deregulated in a substantial proportion of cases and its expression is associated with poor prognosis. However, its expression in breast cancer metastases, which are the main causes of breast cancer-related death, remained to be elucidated. Patients and methods RNA was isolated from 55 primary breast cancers and paired metastases, including regional lymph node (N = 20) and distant metastases (N = 35). APOBEC3B mRNA levels were measured by RT-qPCR. Expression levels of the primary tumors and corresponding metastases were compared, including subgroup analysis by estrogen receptor (ER/ESR1) status. Results Overall, APOBEC3B mRNA levels of distant metastases were significantly higher as compared to the corresponding primary breast tumor (P = 0.0015), an effect that was not seen for loco-regional lymph node metastases (P = 0.23). Subgroup analysis by ER-status showed that increased APOBEC3B levels in distant metastases were restricted to metastases arising from ER-positive primary breast cancers (P = 0.002). However, regarding ER-negative primary tumors, only loco-regional lymph node metastases showed increased APOBEC3B expression when compared to the corresponding primary tumor (P = 0.028). Conclusion APOBEC3B mRNA levels are significantly higher in breast cancer metastases as compared to the corresponding ER-positive primary tumors. This suggests a potential role for APOBEC3B in luminal breast cancer progression, and consequently, a promising role for anti-APOBEC3B therapies in advanced stages of this frequent form of breast cancer. PMID:28141868

  14. Influence of road network and population demand assumptions in evacuation modeling for distant tsunamis

    Science.gov (United States)

    Henry, Kevin; Wood, Nathan J.; Frazier, Tim G.

    2017-01-01

    Tsunami evacuation planning in coastal communities is typically focused on local events where at-risk individuals must move on foot in a matter of minutes to safety. Less attention has been placed on distant tsunamis, where evacuations unfold over several hours, are often dominated by vehicle use and are managed by public safety officials. Traditional traffic simulation models focus on estimating clearance times but often overlook the influence of varying population demand, alternative modes, background traffic, shadow evacuation, and traffic management alternatives. These factors are especially important for island communities with limited egress options to safety. We use the coastal community of Balboa Island, California (USA), as a case study to explore the range of potential clearance times prior to wave arrival for a distant tsunami scenario. We use a first-in–first-out queuing simulation environment to estimate variations in clearance times, given varying assumptions of the evacuating population (demand) and the road network over which they evacuate (supply). Results suggest clearance times are less than wave arrival times for a distant tsunami, except when we assume maximum vehicle usage for residents, employees, and tourists for a weekend scenario. A two-lane bridge to the mainland was the primary traffic bottleneck, thereby minimizing the effect of departure times, shadow evacuations, background traffic, boat-based evacuations, and traffic light timing on overall community clearance time. Reducing vehicular demand generally reduced clearance time, whereas improvements to road capacity had mixed results. Finally, failure to recognize non-residential employee and tourist populations in the vehicle demand substantially underestimated clearance time.

  15. Radioactive iodine (RAI) therapy for distantly metastatic differentiated thyroid cancer (DTC) in juvenile versus adult patients.

    Science.gov (United States)

    Kammori, Makoto; Fukumori, Tatsuya; Sugishita, Yoshiyuki; Hoshi, Masae; Shimizu, Kazuo; Yamada, Tetsu

    2015-01-01

    In general, juvenile differentiated thyroid carcinoma (DTC) demonstrate indolent characteristics and favorable prognosis are observed in comparison with many other carcinomas. However, recurrence is frequent, necessitating additional treatment, including radioactive iodine (RAI) therapy. In this report, the probability of recurrence, prognostic factors, treatment, and outcomes in both juvenile- and adult-onset DTC were analyzed and compared. At our institution, a total of 1552 DTC patients underwent thyroidectomy and/or lymph node dissection. The patients included 23 in their teens, 118 in their twenties, and 1412 in their thirties or older. The risk factors for distant metastases for DTC were male gender, follicular carcinoma, size of the PTC primary tumor, cervical lymph node metastases from PTC, and the presence of more than two distant metastatic foci. Patients with the highest risk underwent RAI ablation in line with institutional guidelines. Although the overall outcome in our juvenile patients was excellent, during follow-up, 4 (17.4%) of the 23 patients developed recurrent disease: 91.3% achieved complete remission, 4.35% partial remission, and 4.35% stable disease, with no disease-related deaths. Among the 118 patients in their twenties to thirties, 1 (0.8%) experienced progressive disease and disease-related death. A younger age at diagnosis and less radical primary surgery without subsequent RAI ablation are factors strongly predictive of distant metastases in patients with juvenile-onset DTC. To reduce the rate of relapse and improve surveillance for recurrent disease, total thyroidectomy followed by RAI appears to be the most beneficial initial treatment for patients with high- and intermediate-risk juvenile DTC.

  16. Literature mining of protein-residue associations with graph rules learned through distant supervision

    Directory of Open Access Journals (Sweden)

    Ravikumar KE

    2012-10-01

    Full Text Available Abstract Background We propose a method for automatic extraction of protein-specific residue mentions from the biomedical literature. The method searches text for mentions of amino acids at specific sequence positions and attempts to correctly associate each mention with a protein also named in the text. The methods presented in this work will enable improved protein functional site extraction from articles, ultimately supporting protein function prediction. Our method made use of linguistic patterns for identifying the amino acid residue mentions in text. Further, we applied an automated graph-based method to learn syntactic patterns corresponding to protein-residue pairs mentioned in the text. We finally present an approach to automated construction of relevant training and test data using the distant supervision model. Results The performance of the method was assessed by extracting protein-residue relations from a new automatically generated test set of sentences containing high confidence examples found using distant supervision. It achieved a F-measure of 0.84 on automatically created silver corpus and 0.79 on a manually annotated gold data set for this task, outperforming previous methods. Conclusions The primary contributions of this work are to (1 demonstrate the effectiveness of distant supervision for automatic creation of training data for protein-residue relation extraction, substantially reducing the effort and time involved in manual annotation of a data set and (2 show that the graph-based relation extraction approach we used generalizes well to the problem of protein-residue association extraction. This work paves the way towards effective extraction of protein functional residues from the literature.

  17. Beclin 1 Expression is Closely Linked to Colorectal Carcinogenesis and Distant Metastasis of Colorectal Carcinoma

    Directory of Open Access Journals (Sweden)

    Mei-Ying Zhang

    2014-08-01

    Full Text Available Beclin 1 participates in development, autophagy, differentiation, anti- apoptosis, neurodegeneration, tumorigenesis and cancer progression. The roles of Beclin 1 in colorectal carcinogenesis and its subsequent progression are still unclear. Here, the mRNA and protein expression of Beclin 1 were determined in colorectal carcinoma and matched mucosa by Reverse transcriptase-polymerase chain reaction and Western blot. Immunohistochemistry and in situ hybridization (ISH were performed on tissue microarryer with colorectal carcinoma, adenoma and mucosa. The expression of Beclin 1 mRNA and protein was found to be higher in colorectal carcinoma than matched mucosa by real-time PCR and Western blot (p < 0.05. According to the ISH data, Beclin 1 expression was lower in colorectal non-neoplastic mucosa (NNM than adenoma and carcinoma (p < 0.05. Immunohistochemically, primary carcinoma showed stronger Beclin 1 expression than NNM and metastatic carcinoma in the liver (p < 0.05. Beclin 1 protein expression was negatively related to liver and distant metastasis (p < 0.05, but not correlated with age, sex, depth of invasion, lymphatic or venous invasion, lymph node metastasis, tumor-node-metastasis (TNM staging, differentiation or serum carcinoembryonic antigen (CEA concentration (p > 0.05. Survival analysis indicated that Beclin 1 expression was not linked to favorable prognosis of the patients with colorectal carcinoma (p > 0.05. Cox’s model indicated that depth of invasion and distant metastasis were independent prognostic factors for colorectal carcinomas (p < 0.05. It was suggested that Beclin 1 expression is closely linked to colorectal carcinogenesis and distant metastasis of colorectal carcinoma.

  18. Distant and new mutations in CTX-M-1 beta-lactamase affect cefotaxime hydrolysis.

    Science.gov (United States)

    Pérez-Llarena, Francisco José; Kerff, Frédéric; Abián, Olga; Mallo, Susana; Fernández, María Carmen; Galleni, Moreno; Sancho, Javier; Bou, Germán

    2011-09-01

    The CTX-M β-lactamases are an increasingly prevalent group of extended-spectrum β-lactamases (ESBL). Point mutations in CTX-M β-lactamases are considered critical for enhanced hydrolysis of cefotaxime. In order to clarify the structural determinants of the activity against cefotaxime in CTX-M β-lactamases, screening for random mutations was carried out to search for decreased activity against cefotaxime, with the CTX-M-1 gene as a model. Thirteen single mutants with a considerable reduction in cefotaxime MICs were selected for biochemical and stability studies. The 13 mutated genes of the CTX-M-1 β-lactamase were expressed, and the proteins were purified for kinetic studies against cephalothin and cefotaxime (as the main antibiotics). Some of the positions, such as Val103Asp, Asn104Asp, Asn106Lys, and Pro107Ser, are located in the (103)VNYN(106) loop, which had been described as important in cefotaxime hydrolysis, although this has not been experimentally confirmed. There are four mutations located close to catalytic residues-Thr71Ile, Met135Ile, Arg164His, and Asn244Asp-that may affect the positioning of these residues. We show here that some distant mutations, such as Ala219Val, are critical for cefotaxime hydrolysis and highlight the role of this loop at the top of the active site. Other distant substitutions, such as Val80Ala, Arg191, Ala247Ser, and Val260Leu, are in hydrophobic cores and may affect the dynamics and flexibility of the enzyme. We describe here, in conclusion, new residues involved in cefotaxime hydrolysis in CTX-M β-lactamases, five of which are in positions distant from the catalytic center.

  19. Detecting changes of a distant gas source with an array of MOX gas sensors.

    Science.gov (United States)

    Pashami, Sepideh; Lilienthal, Achim J; Trincavelli, Marco

    2012-11-27

    We address the problem of detecting changes in the activity of a distant gas source from the response of an array of metal oxide (MOX) gas sensors deployed in an open sampling system. The main challenge is the turbulent nature of gas dispersion and the response dynamics of the sensors. We propose a change point detection approach and evaluate it on individual gas sensors in an experimental setup where a gas source changes in intensity, compound, or mixture ratio. We also introduce an efficient sensor selection algorithm and evaluate the change point detection approach with the selected sensor array subsets.

  20. Detection and genetic characterization of a novel parvovirus distantly related to human bufavirus in domestic pigs.

    Science.gov (United States)

    Hargitai, Renáta; Pankovics, Péter; Kertész, Attila Mihály; Bíró, Hunor; Boros, Ákos; Phan, Tung Gia; Delwart, Eric; Reuter, Gábor

    2016-04-01

    In this study, a novel parvovirus (strain swine/Zsana3/2013/HUN, KT965075) was detected in domestic pigs and genetically characterized by viral metagenomics and PCR methods. The novel parvovirus was distantly related to the human bufaviruses and was detected in 19 (90.5 %) of the 21 and five (33.3 %) of the 15 faecal samples collected from animals with and without cases of posterior paraplegia of unknown etiology from five affected farms and one control farm in Hungary, respectively. Swine/Zsana3/2013/HUN is highly prevalent in domestic pigs and potentially represents a novel parvovirus species in the subfamily Parvovirinae.

  1. drs (Distantly Related sic) Gene Polymorphisms among emm12-Type Streptococcus pyogenes Isolates

    Science.gov (United States)

    Brandt, Claudia M.; Haase, Gerhard; Spellerberg, Barbara; Holland, Regina; Lütticken, Rudolf

    2003-01-01

    Twenty-eight emm12-type Streptococcus pyogenes isolates from patients with invasive and noninvasive infections or from asymptomatic carriers were genetically typed. Sequencing of drs (distantly related sic [streptococcal inhibitor of complement]) genes identified two novel alleles and revealed a polymorphism for drs similar to that of sic. No association was observed between the five different drs alleles and the five restriction patterns of the vir regulon for the isolates studied. These data suggest that drs sequencing may be useful for further differentiation of S. pyogenes isolates with emm12 and identical vir regulon restriction patterns. PMID:12682191

  2. Establishment of Entanglement for Two Atoms Trapped in Two Distant Bad Cavities

    Institute of Scientific and Technical Information of China (English)

    LU Dao-Ming; ZHENG Shi-Biao

    2007-01-01

    A scheme is presented for generation of entangled states for two atoms trapped in two distant bad cavities.The scheme can work with bad cavities with the coupling strength smaller than the cavity decay rate, which is important from the viewpoint of experiment. In the scheme the atoms have no probability of being populated in the excited state and thus the atomic spontaneous emission is suppressed, which increases the probability of success. The fidelity of the entangled state is not affected by the detection efficiency. Furthermore, the scheme does not require the detection of the left-polarized photon and right-polarized photon at the same time.

  3. Virtual-photon-induced quantum phase gates for two distant atoms trapped in separate cavities

    CERN Document Server

    Zheng, Shi-Biao

    2012-01-01

    We propose a scheme for implementing quantum gates for two atoms trapped in distant cavities connected by an optical fiber. The effective long-distance coupling between the two distributed qubits is achieved without excitation and transportation of photons through the optical fiber. Since the cavity modes and fiber mode are never populated and the atoms undergo no transitions, the gate operation is insensitive to the decoherence effect when the thermal photons in the environment are negligible. The scheme opens promising perspectives for networking quantum information processors and implementing distributed and scalable quantum computation.

  4. The imprint of China's first emperor on the distant realm of eastern Shandong.

    Science.gov (United States)

    Feinman, Gary M; Nicholas, Linda M; Hui, Fang

    2010-03-16

    Imperial expansion is recurrent in human history. For early empires, such as in ancient China, this process generally is known from texts that glorify and present the perspective of vectors. The legacy of the Qin king, Shihuangdi, who first unified China in 221 BC, remains vital, but we have few details about the consequences of his distant conquests or how they changed the path of local histories. We integrate documentary accounts with the findings of a systematic regional survey of archaeological sites to provide a holistic context for this imperialistic episode and the changes that followed in coastal Shandong.

  5. The imprint of China’s first emperor on the distant realm of eastern Shandong

    Science.gov (United States)

    Feinman, Gary M.; Nicholas, Linda M.; Hui, Fang

    2010-01-01

    Imperial expansion is recurrent in human history. For early empires, such as in ancient China, this process generally is known from texts that glorify and present the perspective of victors. The legacy of the Qin king, Shihuangdi, who first unified China in 221 BC, remains vital, but we have few details about the consequences of his distant conquests or how they changed the path of local histories. We integrate documentary accounts with the findings of a systematic regional survey of archaeological sites to provide a holistic context for this imperialistic episode and the changes that followed in coastal Shandong. PMID:20194758

  6. Detailed chemical abundances of distant RR Lyrae stars in the Virgo Stellar Stream

    CERN Document Server

    Duffau, S; Vivas, A K; Hansen, C J; Zoccali, M; Catelan, M; Minniti, D; Grebel, E K

    2016-01-01

    We present the first detailed chemical abundances for distant RR Lyrae stars members of the Virgo Stellar Stream (VSS), derived from X-Shooter medium-resolution spectra. Sixteen elements from carbon to barium have been measured in six VSS RR Lyrae stars, sampling all main nucleosynthetic channels. For the first time we will be able to compare in detail the chemical evolution of the VSS progenitor with those of Local Group dwarf spheroidal galaxies (LG dSph) as well as the one of the smooth halo.

  7. Photo-acoustic and video-acoustic methods for sensing distant sound sources

    Science.gov (United States)

    Slater, Dan; Kozacik, Stephen; Kelmelis, Eric

    2017-05-01

    Long range telescopic video imagery of distant terrestrial scenes, aircraft, rockets and other aerospace vehicles can be a powerful observational tool. But what about the associated acoustic activity? A new technology, Remote Acoustic Sensing (RAS), may provide a method to remotely listen to the acoustic activity near these distant objects. Local acoustic activity sometimes weakly modulates the ambient illumination in a way that can be remotely sensed. RAS is a new type of microphone that separates an acoustic transducer into two spatially separated components: 1) a naturally formed in situ acousto-optic modulator (AOM) located within the distant scene and 2) a remote sensing readout device that recovers the distant audio. These two elements are passively coupled over long distances at the speed of light by naturally occurring ambient light energy or other electromagnetic fields. Stereophonic, multichannel and acoustic beam forming are all possible using RAS techniques and when combined with high-definition video imagery it can help to provide a more cinema like immersive viewing experience. A practical implementation of a remote acousto-optic readout device can be a challenging engineering problem. The acoustic influence on the optical signal is generally weak and often with a strong bias term. The optical signal is further degraded by atmospheric seeing turbulence. In this paper, we consider two fundamentally different optical readout approaches: 1) a low pixel count photodiode based RAS photoreceiver and 2) audio extraction directly from a video stream. Most of our RAS experiments to date have used the first method for reasons of performance and simplicity. But there are potential advantages to extracting audio directly from a video stream. These advantages include the straight forward ability to work with multiple AOMs (useful for acoustic beam forming), simpler optical configurations, and a potential ability to use certain preexisting video recordings. However

  8. Does distant homology with Evf reveal a lipid binding site in Bacillus thuringiensis cytolytic toxins?

    Science.gov (United States)

    Rigden, Daniel J

    2009-05-19

    The Cry and Cyt classes of insecticidal toxins derived from the sporulating bacterium Bacillus thuringiensis are valuable substitutes for synthetic pesticides in agricultural contexts. Crystal structures and many biochemical data have provided insights into their molecular mechanisms, generally thought to involve oligomerization and pore formation, but have not localised the site on Cyt toxins responsible for selective binding of phospholipids containing unsaturated fatty acids. Here, distant homology between the structure of Cyt toxins and Erwinia virulence factor (Evf) is demonstrated which, along with sequence conservation analysis, allows a putative lipid binding site to be localised in the toxins.

  9. Optical depth for VHE gamma-rays from distant sources from a generic EBL density

    OpenAIRE

    Raue, M.; Mazin, D.

    2008-01-01

    Very-high-energy (VHE; E>100GeV) gamma-rays from distant sources suffer attenuation through pair-production with low energy photons from the diffuse extragalactic photon fields in the ultraviolet (UV) to far-infrared (FIR) (commonly referred to as Extragalactic Background Light; EBL). When modeling the intrinsic spectra of the VHE gamma-ray sources it is crucial to correctly account for the attenuation. Unfortunately, direct measurements of the EBL are difficult and the knowledge about the EB...

  10. When threats foreign turn domestic: Two ways for distant realistic intergroup threats to carry over into local intolerance.

    Science.gov (United States)

    Bouman, Thijs; van Zomeren, Martijn; Otten, Sabine

    2015-09-01

    In times of economic downturn, perceived realistic intergroup threats (e.g., labour competition) often dominate political and media discourse. Although local outgroups (e.g., local immigrants) can be experienced as sources of realistic threats, we propose that such threats can also be perceived to be caused by distant outgroups (e.g., European Union members perceiving Greece to threaten their economies) and that such distant threats can carry over into local intolerance (e.g., increasing intolerance towards local immigrant groups). We predicted and found in two studies that perceived distant realistic threats carried over into local intolerance via two different pathways. First, direct reactions towards the distant outgroup can generalize to culturally similar local outgroups (the group-based association pathway). Secondly, Study 2 indicated that when the distant threat was attributed to stereotypical outgroup traits (e.g., being lazy), distant realistic threats activated local realistic threats, which subsequently influenced local intolerance (the threat-based association pathway). Taken together, our studies indicate that perceived realistic threats foreign can turn domestic, but in two different ways.

  11. Effects of temperature and food on the development of Dysdercus maurus Distant (Hemiptera, Pyrrhocoridae); Efeitos da temperatura e do alimento no desenvolvimento de Dysdercus maurus Distant (Hemiptera, Pyrrhocoridae)

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Fabio Souto [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropedica, RJ (Brazil). Dept. de Ciencias Ambientais], e-mail: fbio_almeida@yahoo.com.br; Goncalves, Lenicio [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropedica, RJ (Brazil). Dept. de Biologia Animal. Area de Biologia], e-mail: lencygon@globo.com

    2007-10-15

    Dysdercus maurus Distant, 1901 (Hemiptera, Pyrrhocoridae) is an important pest on Gossypium spp. (cotton tree), Citrus sinensis Osbeck (Rutaceae) and Citrus reticulata Blanco (Rutaceae) crops. This insect also feeds on seeds of Chorisia speciosa St. Hil. (Bombacaceae). This work aimed to evaluate the effects of temperature and food on the development of D. maurus. Eight treatments were carried out, in six of them bugs were fed with seeds of C. speciosa and kept at 15, 18, 20, 25 and 30 {+-} 1 deg C, 80 {+-} 3% RH and 12h photo phase or in laboratory conditions (23.5 {+-} 2.6 deg C, 73.3 {+-} 9.9 % RH), and in the other two treatments bugs were fed with seeds of cotton variety IAC-22 and kept at 25 or 30 deg C. In all treatments five immature stages were observed. The increase of temperature caused reduction in the developmental time. The temperature of 15 deg C disabled nymphal eclosion and was also lethal to those nymphs ecloded at other temperatures. The lower mortality of nymphs occurred in the temperature of 25 deg C with cotton as food (24.07%). The lower threshold temperature (Tb) occurred for the first instar (11.54 deg C) and the higher for the second instar (15.33 deg C). The females of D. maurus required more degree-days (329.93 degree-days) than males (300.49 degree-days) until adult emergence. (author)

  12. Historically aggressive types of follicular cell-derived thyroid cancer often have radioactive avid distant metastases: a study of 314 patients with distant metastases at a single institution

    Energy Technology Data Exchange (ETDEWEB)

    Tala, H.P.; Rondeau, G.; Fagin, J.A.; Tuttle, R.M. [Endocrinology Division, Department of Medicine, Nuclear Medicine Division, Memorial Sloan Kettering Cancer Center, New-York (United States); Ghossein, R.A. [Pathology Department, Nuclear Medecine Division, Memorial Sloan Kettering Cancer Center, New-York (United States); Grewal, R.K.; Larson, S.M. [Radiology Department, Nuclear Medicine Division, Memorial Sloan Kettering Cancer Center, New-York (United States)

    2012-07-01

    Radioactive iodine (RAI) remains one of the primary treatment options for metastatic, follicular cell derived thyroid cancers. The aim of this study was to determine the likelihood that metastatic lesions arising from one of the aggressive thyroid cancer histologies [tall cell variant of papillary thyroid carcinoma (TCV-PTC), poorly differentiated thyroid carcinoma (PDTC) and Hurthle cell carcinoma (HCC)] would demonstrate sufficient RAI avidity for visualization on RAI scanning and therefore could potentially benefit from RAI therapy. The study shows that in patients selected for RAI scanning or therapy at our center, RAI avid lesions can be identified in more than two thirds of the patients with distant metastases arising in the setting of C-PTC, WD-FTC, FV-PTC, TCV-PTC, or PDTC primary tumors. While RAI avidity on a post-therapy scan does not always correlate with clinically significant tumor killing activity, it is likely that some of these patients with RAI avid metastatic disease did obtain a clinical benefit

  13. Interaction corrections at intermediate temperatures: magneto-resistance in parallel field

    OpenAIRE

    Zala, Gabor; Narozhny, B. N.; Aleiner, I. L.

    2001-01-01

    We consider the correction to conductivity of a 2D electron gas due to electron-electron interaction in the parallel magnetic field at arbitrary relation between temperature and the elastic mean free time. The correction exhibits non-trivial dependence on both temperature and the field. This dependence is determined by the Fermi liquid constant, which accounts for the spin-exchange interaction. In particular, the sign of the slope of the temperature dependence is not universal and can change ...

  14. APEX Snaps First Close-up of Star Factories in Distant Universe

    Science.gov (United States)

    2010-03-01

    For the first time, astronomers have made direct measurements of the size and brightness of regions of star-birth in a very distant galaxy, thanks to a chance discovery with the APEX telescope. The galaxy is so distant, and its light has taken so long to reach us, that we see it as it was 10 billion years ago. A cosmic "gravitational lens" is magnifying the galaxy, giving us a close-up view that would otherwise be impossible. This lucky break reveals a hectic and vigorous star-forming life for galaxies in the early Universe, with stellar nurseries forming one hundred times faster than in more recent galaxies. The research is published online today in the journal Nature. Astronomers were observing a massive galaxy cluster [1] with the Atacama Pathfinder Experiment (APEX) telescope, using submillimetre wavelengths of light, when they found a new and uniquely bright galaxy, more distant than the cluster and the brightest very distant galaxy ever seen at submillimetre wavelengths. It is so bright because the cosmic dust grains in the galaxy are glowing after being heated by starlight. The new galaxy has been given the name SMM J2135-0102. "We were stunned to find a surprisingly bright object that wasn't at the expected position. We soon realised it was a previously unknown and more distant galaxy being magnified by the closer galaxy cluster," says Carlos De Breuck from ESO, a member of the team. De Breuck was making the observations at the APEX telescope on the plateau of Chajnantor at an altitude of 5000 m in the Chilean Andes. The new galaxy SMM J2135-0102 is so bright because of the massive galaxy cluster that lies in the foreground. The vast mass of this cluster bends the light of the more distant galaxy, acting as a gravitational lens [2]. As with a telescope, it magnifies and brightens our view of the distant galaxy. Thanks to a fortuitous alignment between the cluster and the distant galaxy, the latter is strongly magnified by a factor of 32. "The magnification

  15. Conserved Noncoding Elements in the Most Distant Genera of Cephalochordates: The Goldilocks Principle

    Science.gov (United States)

    Yue, Jia-Xing; Kozmikova, Iryna; Ono, Hiroki; Nossa, Carlos W.; Kozmik, Zbynek; Putnam, Nicholas H.; Yu, Jr-Kai; Holland, Linda Z.

    2016-01-01

    Cephalochordates, the sister group of vertebrates + tunicates, are evolving particularly slowly. Therefore, genome comparisons between two congeners of Branchiostoma revealed so many conserved noncoding elements (CNEs), that it was not clear how many are functional regulatory elements. To more effectively identify CNEs with potential regulatory functions, we compared noncoding sequences of genomes of the most phylogenetically distant cephalochordate genera, Asymmetron and Branchiostoma, which diverged approximately 120–160 million years ago. We found 113,070 noncoding elements conserved between the two species, amounting to 3.3% of the genome. The genomic distribution, target gene ontology, and enriched motifs of these CNEs all suggest that many of them are probably cis-regulatory elements. More than 90% of previously verified amphioxus regulatory elements were re-captured in this study. A search of the cephalochordate CNEs around 50 developmental genes in several vertebrate genomes revealed eight CNEs conserved between cephalochordates and vertebrates, indicating sequence conservation over >500 million years of divergence. The function of five CNEs was tested in reporter assays in zebrafish, and one was also tested in amphioxus. All five CNEs proved to be tissue-specific enhancers. Taken together, these findings indicate that even though Branchiostoma and Asymmetron are distantly related, as they are evolving slowly, comparisons between them are likely optimal for identifying most of their tissue-specific cis-regulatory elements laying the foundation for functional characterizations and a better understanding of the evolution of developmental regulation in cephalochordates. PMID:27412606

  16. Distant thermography and analysis of pupillary reactions in diagnostics of primary openangle glaucoma

    Directory of Open Access Journals (Sweden)

    Sagaidachny A.A.

    2012-06-01

    Full Text Available Research objective: comparative analysis of distant thermography, Doppler ultrasound and pupillary reactions in patients with primary open-angle glaucoma at various stages of the disease with compensated intraocular pressure. Materials. 129 patients (216 eyes with diagnosis of POAG at various stages ofthe disease (the main group have been examined. Intraocular pressure has been normalized with medications, or with medications + laser surgery. The control group has consisted of patients with initial and immature cataract of similar age and sex (30 patients — 52 eyes. All patients have experienced thermal, Doppler study, and a study of pupil response to light. Results. It has been revealed that the temperature ofthe open optic fissure in patients with POAG correlated with hemodynamics in the central retinal artery and short posterior ciliary arteries. It has been also noted the reduction of pupillary reaction in the progression of glaucoma optic neuropathy. Conclusion. Data of distant thermography, Doppler ultrasound and video recording of pupillary reaction are different with various stages of glaucoma process. The investigation allows to use these methods for monitoring of patients with primary open-angle glaucoma

  17. Two Distant Halo Velocity Groups Discovered by the Palomar Transient Factory

    CERN Document Server

    Sesar, B; Levitan, D; Grillmair, C J; Juric, M; Kirby, E N; Laher, R R; Ofek, E O; Surace, J A; Kulkarni, S R; Prince, T A

    2012-01-01

    We report the discovery of two new halo velocity groups (Cancer groups A and B) traced by 8 distant RR Lyrae stars and observed by the Palomar Transient Factory (PTF) survey at R.A.~129 deg, Dec~20 deg (l~205 deg, b~32 deg). Located at 92 kpc from the Galactic center (86 kpc from the Sun), these are some of the most distant substructures in the Galactic halo known to date. Follow-up spectroscopic observations with the Palomar Observatory 5.1-m Hale telescope and W. M. Keck Observatory 10-m Keck I telescope indicate that the two groups are moving away from the Galaxy at v_{gsr} = 78.0+-5.6 km/s (Cancer group A) and v_{gsr} = 16.3+-7.1 km/s (Cancer group B). The groups have velocity dispersions of \\sigma_{v_{gsr}}=12.4+-5.0 km/s and \\sigma_{v_{gsr}}=14.9+-6.2 km/s, and are spatially extended (about several kpc) making it very unlikely that they are bound systems, and are more likely to be debris of tidally disrupted dwarf galaxies or globular clusters. Both groups are metal-poor (median metallicities of [Fe/H] ...

  18. All-optical link for direct comparison of distant optical clocks

    CERN Document Server

    Fujieda, Miho; Nagano, Shigeo; Yamaguchi, Atsushi; Hachisu, Hidekazu; Ido, Tetsuya

    2011-01-01

    We developed an all-optical link system for making remote comparisons of two distant ultra-stable optical clocks. An optical carrier transfer system based on a fiber interferometer was employed to compensate the phase noise accumulated during the propagation through a fiber link. Transfer stabilities of $2\\times10^{-15}$ at 1 second and $4\\times10^{-18}$ at 1000 seconds were achieved in a 90-km link. An active polarization control system was additionally introduced to maintain the transmitted light in an adequate polarization, and consequently, a stable and reliable comparison was accomplished. The instabilities of the all-optical link system, including those of the erbium doped fiber amplifiers (EDFAs) which are free from phase-noise compensation, were below $2\\times10^{-15}$ at 1 second and $7\\times10^{-17}$ at 1000 seconds. The system was available for the direct comparison of two distant $^{87}$Sr lattice clocks via an urban fiber link of 60 km. This technique will be essential for the measuring the repro...

  19. Plasma and magnetic field variations in the distant magnetotail associated with near-earth substorm effects

    Science.gov (United States)

    Baker, D. N.; Bame, S. J.; Mccomas, D. J.; Zwickl, R. D.; Slavin, J. A.; Smith, E. J.

    1987-01-01

    Examination of many individual event periods in the ISEE 3 deep-tail data set has suggested that magnetospheric substorms produce a characteristic pattern of effects in the distant magnetotail. During the growth, or tail-energy-storage phase of substorms, the magnetotail appears to grow diametrically in size, often by many earth radii. Subsequently, after the substorm expansive phase onset at earth, the distant tail undergoes a sequence of plasma, field, and energetic-particle variations as large-scale plasmoids move rapidly down the tail following their disconnection from the near-earth plasma sheet. ISEE 3 data are appropriate for the study of these effects since the spacecraft remained fixed within the nominal tail location for long periods. Using newly available auroral electrojet indices (AE and AL) and Geo particle data to time substorm onsets at earth, superposed epoch analyses of ISEE 3 and near-earth data prior to, and following, substorm expansive phase onsets have been performed. These analyses quantify and extend substantially the understanding of the deep-tail pattern of response to global substorm-induced dynamical effects.

  20. Extracting microRNA-gene relations from biomedical literature using distant supervision.

    Science.gov (United States)

    Lamurias, Andre; Clarke, Luka A; Couto, Francisco M

    2017-01-01

    Many biomedical relation extraction approaches are based on supervised machine learning, requiring an annotated corpus. Distant supervision aims at training a classifier by combining a knowledge base with a corpus, reducing the amount of manual effort necessary. This is particularly useful for biomedicine because many databases and ontologies have been made available for many biological processes, while the availability of annotated corpora is still limited. We studied the extraction of microRNA-gene relations from text. MicroRNA regulation is an important biological process due to its close association with human diseases. The proposed method, IBRel, is based on distantly supervised multi-instance learning. We evaluated IBRel on three datasets, and the results were compared with a co-occurrence approach as well as a supervised machine learning algorithm. While supervised learning outperformed on two of those datasets, IBRel obtained an F-score 28.3 percentage points higher on the dataset for which there was no training set developed specifically. To demonstrate the applicability of IBRel, we used it to extract 27 miRNA-gene relations from recently published papers about cystic fibrosis. Our results demonstrate that our method can be successfully used to extract relations from literature about a biological process without an annotated corpus. The source code and data used in this study are available at https://github.com/AndreLamurias/IBRel.

  1. Instanton induced Yukawa couplings from distant E3 and E(-1) instantons

    Energy Technology Data Exchange (ETDEWEB)

    Goodsell, Mark D. [Sorbonne Universités, UPMC Univ Paris 06, UMR 7589, LPTHE,F-75005, Paris (France); CNRS, UMR 7589, LPTHE,F-75005, Paris (France); Witkowski, Lukas T. [Institute for Theoretical Physics, University of Heidelberg,Philosophenweg 19, 69120 Heidelberg (Germany)

    2016-01-07

    We calculate non-perturbative contributions to Yukawa couplings on D3-branes at orbifold singularities due to E3 and fractional E(-1) instantons which do not intersect the visible sector branes. While distant E3 instantons on bulk cycles typically contribute to Yukawa couplings, we find that distant fractional E(-1) can also give rise to new Yukawa couplings. However, fractional E(-1) instantons only induce Yukawa couplings if they are located at a singularity which shares a collapsed homologous two-cycle with the singularity supporting the visible sector. The non-perturbative contributions to Yukawa couplings exhibit a different flavour structure than the tree-level Yukawa couplings and, as a result, they can be sources of flavour violation. This is particularly relevant for schemes of moduli stabilisation which rely on superpotential contributions from E3 instantons, such as KKLT or the Large Volume Scenario. As a byproduct of our analysis, we shed some new light on the properties of annulus diagrams with matter field insertions in stringy instanton calculus.

  2. Imaging polarimetry of distant comets at the 6-m BTA telescope of the SAO RAS

    Science.gov (United States)

    Ivanova, Oleksandra; Afanasiev, Viktor; Rosenbush, Vera; Kiselev, Nikolai

    2016-07-01

    Results of the recent polarimetric observations of distant comets C/2013 V4 (Catalina), C/2014 A4 (SONEAR), C/2010 S1 (LINEAR), C/2010 R1 (LINEAR), and 29P/Schwassmann-Wachmann 1 are presented together with analysis of their photometry and spectroscopy. Observations were carried out at the 6-m telescope BTA of the SAO RAS with the multi-mode focal reducer SCORPIO-2 from 2011 to 2015. Comets were observed in the range of heliocentric distances from 4.2 to 7.0 AU and phase angles from 4.9 to 9.4 degrees. The maps of intensity and linear polarization over the coma are derived. The comets observed show a considerable activity at heliocentric distances far exceeding a zone of water sublimation. Molecular emissions were only detected in the spectra of comet 29P/Schwassmann-Wachmann 1. The linear polarization of distant comets with a high level of activity is the first ever measured at the heliocentric distances larger than 5 AU. The degree of linear polarization (from -2 to -3.7%) for these comets is significantly higher (in absolute value) than the typical value of the whole coma polarization (about -1.5 %) at the minimum of negative polarization branch for close to the Sun comets.

  3. Cryptic distant relatives are common in both isolated and cosmopolitan genetic samples.

    Directory of Open Access Journals (Sweden)

    Brenna M Henn

    Full Text Available Although a few hundred single nucleotide polymorphisms (SNPs suffice to infer close familial relationships, high density genome-wide SNP data make possible the inference of more distant relationships such as 2(nd to 9(th cousinships. In order to characterize the relationship between genetic similarity and degree of kinship given a timeframe of 100-300 years, we analyzed the sharing of DNA inferred to be identical by descent (IBD in a subset of individuals from the 23andMe customer database (n = 22,757 and from the Human Genome Diversity Panel (HGDP-CEPH, n = 952. With data from 121 populations, we show that the average amount of DNA shared IBD in most ethnolinguistically-defined populations, for example Native American groups, Finns and Ashkenazi Jews, differs from continentally-defined populations by several orders of magnitude. Via extensive pedigree-based simulations, we determined bounds for predicted degrees of relationship given the amount of genomic IBD sharing in both endogamous and 'unrelated' population samples. Using these bounds as a guide, we detected tens of thousands of 2(nd to 9(th degree cousin pairs within a heterogenous set of 5,000 Europeans. The ubiquity of distant relatives, detected via IBD segments, in both ethnolinguistic populations and in large 'unrelated' populations samples has important implications for genetic genealogy, forensics and genotype/phenotype mapping studies.

  4. Motion of a distant solid particle in a shear flow along a porous slab

    Science.gov (United States)

    Khabthani, S.; Sellier, A.; Feuillebois, F.

    2013-12-01

    The motion of a solid and no-slipping particle immersed in a shear flow along a sufficiently porous slab is investigated. The fluid flow outside and inside of the slab is governed by the Stokes and Darcy equations, respectively, and the so-called Beavers and Joseph slip boundary conditions are enforced on the slab surface. The problem is solved for a distant particle with length scale a in terms of the small parameter a/ d where d designates the large particle-slab separation. This is achieved by asymptotically inverting a relevant boundary-integral equation on the particle surface, which has been recently proposed for any particle location (distant or close particle) in Khabthani et al. (J Fluid Mech 713:271-306, 2012). It is found that at order O( a/ d) the slab behaves for any particle shape as a solid plane no-slip wall while the slab properties (thickness, permeability, associated slip length) solely enter at O(( a/ d)2). Moreover, for a spherical particle, the numerical results published in Khabthani et al. (J Fluid Mech 713:271-306, 2012) perfectly agree with the present asymptotic analysis.

  5. Extracting microRNA-gene relations from biomedical literature using distant supervision

    Science.gov (United States)

    Clarke, Luka A.; Couto, Francisco M.

    2017-01-01

    Many biomedical relation extraction approaches are based on supervised machine learning, requiring an annotated corpus. Distant supervision aims at training a classifier by combining a knowledge base with a corpus, reducing the amount of manual effort necessary. This is particularly useful for biomedicine because many databases and ontologies have been made available for many biological processes, while the availability of annotated corpora is still limited. We studied the extraction of microRNA-gene relations from text. MicroRNA regulation is an important biological process due to its close association with human diseases. The proposed method, IBRel, is based on distantly supervised multi-instance learning. We evaluated IBRel on three datasets, and the results were compared with a co-occurrence approach as well as a supervised machine learning algorithm. While supervised learning outperformed on two of those datasets, IBRel obtained an F-score 28.3 percentage points higher on the dataset for which there was no training set developed specifically. To demonstrate the applicability of IBRel, we used it to extract 27 miRNA-gene relations from recently published papers about cystic fibrosis. Our results demonstrate that our method can be successfully used to extract relations from literature about a biological process without an annotated corpus. The source code and data used in this study are available at https://github.com/AndreLamurias/IBRel. PMID:28263989

  6. Using distant supervised learning to identify protein subcellular localizations from full-text scientific articles.

    Science.gov (United States)

    Zheng, Wu; Blake, Catherine

    2015-10-01

    Databases of curated biomedical knowledge, such as the protein-locations reflected in the UniProtKB database, provide an accurate and useful resource to researchers and decision makers. Our goal is to augment the manual efforts currently used to curate knowledge bases with automated approaches that leverage the increased availability of full-text scientific articles. This paper describes experiments that use distant supervised learning to identify protein subcellular localizations, which are important to understand protein function and to identify candidate drug targets. Experiments consider Swiss-Prot, the manually annotated subset of the UniProtKB protein knowledge base, and 43,000 full-text articles from the Journal of Biological Chemistry that contain just under 11.5 million sentences. The system achieves 0.81 precision and 0.49 recall at sentence level and an accuracy of 57% on held-out instances in a test set. Moreover, the approach identifies 8210 instances that are not in the UniProtKB knowledge base. Manual inspection of the 50 most likely relations showed that 41 (82%) were valid. These results have immediate benefit to researchers interested in protein function, and suggest that distant supervision should be explored to complement other manual data curation efforts.

  7. Analysis of lightning-ionosphere interaction using simultaneous records of source current and 380 km distant electric field

    Science.gov (United States)

    Azadifar, Mohammad; Li, Dongshuai; Rachidi, Farhad; Rubinstein, Marcos; Diendorfer, Gerhard; Schulz, Wolfgang; Pichler, Hannes; Rakov, Vladimir A.; Paolone, Mario; Pavanello, Davide

    2017-06-01

    We present simultaneous current and wideband electric field waveforms at 380 km associated with upward lightning flashes initiated from the Säntis Tower, Switzerland. To the best of our knowledge, the dataset presented in this study includes the first simultaneous records of lightning currents and associated fields featuring ionospheric reflections for natural upward flashes, and the longest distance at which natural upward lightning fields have been measured simultaneously with their causative currents. The intervals between the groundwave and skywave arrival times are used to estimate ionospheric reflection heights during day and night times using the so-called zero-to-zero and peak-to-peak methods. During daytime, the mean ionospheric reflection heights, obtained using the two different delay estimation approaches, are about 78 and 76 km, corresponding to the D layer. The mean reflection height at nighttime is about 90 and 89 km, corresponding to the E layer. We present a full-wave, finite-difference time-domain (FDTD) analysis of the electric field propagation including the effect of the ionospheric reflections. The FDTD simulation results are compared with the measured fields associated with upward flashes initiated from the Säntis Tower. It is found that the model reproduces reasonably well the measured waveforms and the times of arrival of the one-hop and two-hop skywaves relative to the groundwave.

  8. Distant Metastases Following Permanent Interstitial Brachytherapy for Patients With Clinically Localized Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Taira, Al V. [Western Radiation Oncology, Mountain View, California (United States); Merrick, Gregory S., E-mail: gmerrick@urologicresearchinstitute.org [Schiffler Cancer Center, Wheeling Jesuit University, Wheeling, West Virginia (United States); Galbreath, Robert W.; Butler, Wayne M.; Lief, Jonathan [Schiffler Cancer Center, Wheeling Jesuit University, Wheeling, West Virginia (United States); Adamovich, Edward [Department of Pathology, Wheeling Hospital, Wheeling, West Virginia (United States); Wallner, Kent E. [Puget Sound Healthcare Corporation, Group Health Cooperative, University of Washington, Seattle, Washington (United States)

    2012-02-01

    Purpose: Recent publications have suggested high-risk patients undergoing radical prostatectomy have a lower risk of distant metastases and improved cause-specific survival (CSS) than patients receiving definitive external beam radiation therapy (XRT). To date, none of these studies has compared distant metastases and CSS in brachytherapy patients. In this study, we evaluate such parameters in a consecutive cohort of brachytherapy patients. Methods and Materials: From April 1995 to June 2007, 1,840 consecutive patients with clinically localized prostate cancer were treated with brachytherapy. Risk groups were stratified according to National Comprehensive Cancer Network ( (www.nccn.org)) guidelines. Subgroups of 658, 893, and 289 patients were assigned to low, intermediate, and high-risk categories. Median follow-up was 7.2 years. Along with brachytherapy implantation, 901 (49.0%) patients received supplemental XRT, and 670 (36.4%) patients received androgen deprivation therapy (median duration, 4 months). The mode of failure (biochemical, local, or distant) was determined for each patient for whom therapy failed. Cause of death was determined for each deceased patient. Multiple parameters were evaluated for impact on outcome. Results: For the entire cohort, metastases-free survival (MFS) and CSS at 12 years were 98.1% and 98.2%, respectively. When rates were stratified by low, intermediate, and high-risk groups, the 12-year MFS was 99.8%, 98.1%, and 93.8% (p < 0.001), respectively. CSS rates were 99.8%, 98.0%, and 95.3% (p < 0.001) for low, intermediate, and high-risk groups, respectively. Biochemical progression-free survival was 98.7%, 95.9% and 90.4% for low, intermediate, and high-risk patients, respectively (p < 0.001). In multivariate Cox-regression analysis, MFS was mostly closely related to Gleason score and year of treatment, whereas CSS was most closely associated with Gleason score. Conclusions: Excellent CSS and MFS rates are achievable with high

  9. The Distant Outer Gas Arm between l=35 and l=45

    Science.gov (United States)

    Su, Yang; Sun, Yan; Li, Chong; Zhang, Shaobo; Zhou, Xin; Fang, Min; Yang, Ji; Chen, Xuepeng

    2016-09-01

    The Galactic plane has been mapped from l = 34.°75 to 45.°25 and b = -5.°25 to 5.°25 in the CO (J = 1-0) emission with the 13.7 m telescope of the Purple Mountain Observatory. The unbiased survey covers a large area of 110 square degrees sampled every 30″ with a velocity resolution of ˜ 0.2 {km} {{{s}}}-1. In this paper, we present the result of an unbiased CO survey of this longitude and latitude range in the velocity range from -60 to -10 {km} {{{s}}}-1. Over 500 molecular clouds (MCs) are picked out from the 12CO (J = 1-0) emission, and 131 of these MCs are associated with 13CO emission. The distant MCs, which lie beyond the solar circle and are mostly concentrated in the Galactic plane, trace the large-scale molecular gas structure over 10 degrees of Galactic azimuth. We find that the distribution of the distant MCs can be well fitted by a Gaussian function with a full width at half maximum (FWHM) of 0.°7 with the Galactic latitude. We suggest that the CO emission of the segment is from the Outer Arm. The physical mid-plane traced by the Outer Arm seems to be slightly displaced from the IAU-defined plane on a large scale, which could be explained by the warped plane at large Galactocentric distances of ≳10 kpc and the apparent tilted mid-plane to the projected IAU-defined plane caused by the Sun’s z-height above the disk for distances near and within the Solar circle. After removing the effect of the warp and tilted structure, the scale height of the MCs in the Outer Arm is about 0.°6 or 160 pc at a heliocentric distance of 15 kpc. If the inner plane of our Galaxy is flat, we can derive an upper limit of the Sun’s offset of ˜17.1 pc above the physical mid-plane of the Milky Way. We also discuss the correlations between the physical parameters of the distant MCs, which is quite consistent with the result of other studies of this parameter.

  10. Frequency and Correlates of Distant Visual Impairment in Patients with Schizophrenia, Bipolar Disorder, and Major Depressive Disorder.

    Science.gov (United States)

    Zheng, W; Tang, L R; Correll, C U; Ungvari, G S; Chiu, H F K; Xiang, Y Q; Xiang, Y T

    2015-09-01

    Distant visual impairment in the severely mentally ill is under-researched. This study aimed to assess the frequency and correlates of distant visual impairment in a cohort of Chinese psychiatric patients, including its effect on their quality of life. Adult psychiatric inpatients with schizophrenia, bipolar disorder, and major depressive disorder consecutively admitted to a psychiatric hospital in Beijing, China underwent assessments of psychopathology (Brief Psychiatric Rating Scale, 16-item Quick Inventory of Depressive Symptomatology [Self-Report]), quality of life (12-item Short-Form Medical Outcomes Study [SF-12], 25-item National Eye Institute Visual Function Questionnaire [NEI-VFQ25]), adverse effects (Udvalg for Kliniske Undersøgelser Side Effect Rating Scale), and presenting (as opposed to uncorrected) distant visual acuity (Logarithm of the Minimum Angle of Resolution [LogMAR] chart with patients wearing spectacles, if they owned them). Distant visual impairment was defined as binocular distant visual acuity of a LogMAR score of ≥ 0.5 (visual impairment was 12.6% (15.2% with schizophrenia, 11.9% with bipolar disorder, 8.8% with major depressive disorder). In multiple logistic regression analysis, distant visual impairment was significantly associated with ocular disease only (p = 0.002, odds ratio = 3.2, 95% confidence interval = 1.5-6.7). Controlling for the confounding effect of ocular disease, patients with distant visual impairment had a lower quality of life in the general vision domain of the NEI-VFQ25 (F[2, 353] = 9.5, p = 0.002) compared with those without. No differences in the physical and mental domains of the SF-12 and in other domains of the NEI-VFQ25 were noted in these 2 groups. One-eighth of middle-aged severely mentally ill patients had distant visual impairment. Considering the impact of distant visual impairment on daily functioning, severely mentally ill patients need to be screened for impaired eyesight as part of their

  11. Electromyographic studies regarding denervation potentials in skeletal muscles at sites near and distant from the burn in rats.

    Science.gov (United States)

    Sajadi, Simin; Mansoori, Korosh; Forogh, Bijan; Fatemi, Mohammad Javad; Ahadi, Tannaz; Chahardoli Razji, Mahnaz

    2016-04-01

    Changes in membrane AChRs in skeletal muscles located near or distant from burn injury similar to denervated muscles may make electrodiagnostic features indistinguishable from true neuropathic changes. The aim of this study was to examine electrodiagnostic changes of muscles at sites local and distant from the burn after thermal injuries due to neuromuscular junction dysfunction. A total of 40 adult male rats were randomly allocated to four groups. Rats in group 1 received thermal burn injury over gastrocnemius muscle of one leg and sham burn on the other leg. A 20-25% and 30-35% surface body area burn and also 30-35% surface body area sham burn were produced at distant site from gastrocnemius muscle in group 2, 3 and 4, respectively. To explore any fibrillation potential, the rats underwent serial electromyographic studies of bilateral gastrocnemius muscles over 5 weeks after burn injury. There were no denervation potentials either in muscles at sites distant from 20-25% and 30-35% of total body surface area burns or in muscles beneath the burn. In the present study on rats, thermal burn injury could not make fibrillation potentials in the electrodiagnostic study of muscles located near and distant from the burn site.

  12. Distant (200-238 Rsub(e)) magnetotail lobe characteristics during quiet solar wind conditions

    Energy Technology Data Exchange (ETDEWEB)

    Tsurutani, B.T.; Burton, M.E.; Smith, E.J.; Jones, D.E.; Lepping, R.P.; Lazarus, A.J.

    1987-03-01

    The distance (X = 200-238 Rsub(e)) tail lobe average properties under quiet solar wind conditions have been determined using simultaneous ISEE-3 magnetic field and IMP-8 magnetic field and plasma observations. Under external solar wind pressures of Psub(ext) B/sup 2/8..pi.. + Nk(Tsub(e) + Tsub(i) <5x10/sup -10/ dynes cm/sup -2/, an average tail lobe field strength of 7.1 + - 1.2 nT and average plasma beta (8..pi.. nk T/B/sup 2/) of 0.3 are determined. It is concluded that under quiet solar wind conditions, the distant tail lobes are typically dominated by the magnetic field pressure.

  13. A Ninth Planet Would Produce a Distinctly Different Distant Kuiper Belt

    CERN Document Server

    Lawler, S M; Kaib, N; Bannister, M T; Gladman, B; Kavelaars, J J

    2016-01-01

    The orbital element distribution of trans-Neptunian objects (TNOs) with large pericenters has been suggested to be influenced by the presence of an undetected, large planet at 200 or more AU from the Sun. We perform 4 Gyr N-body simulations with the currently known Solar System planetary architecture, plus a 10 Earth mass planet with similar orbital parameters to those suggested by Batygin and Brown (2016) or Trujillo and Sheppard (2014), and a hundred thousand test particles in an initial planetesimal disk. We find that including a distant superearth-mass ninth planet produces a substantially different orbital distribution for the scattering and detached TNOs, raising the pericenters and inclinations of moderate semimajor axis (50 < a < 500 AU) objects. We test whether this signature is detectable via a simulator with the observational characteristics of four precisely characterized TNO surveys. We find that the qualitatively very distinct Solar System models that include a ninth planet are essentially...

  14. Hyperparathyroidism caused by distant pulmonary lesions and parathyromatosis after ethanol injection/parathyroidectomy for secondary hyperparathyroidism.

    Science.gov (United States)

    Nakamura, Michio; Tanaka, Kiho; Fujii, Takeshi

    2017-01-11

    Secondary hyperparathyroidism (SHPT) treatment includes parathyroidectomy and percutaneous ethanol injection therapy (PEIT), which are invasive procedures. The condition in which benign hyperfunctioning parathyroid tissue is distributed throughout the neck and mediastinum is termed parathyromatosis. Here, we present the case of a 51-year-old woman who began hemodialysis in 1986 due to chronic kidney disease of unknown etiology and developed SHPT in 1999. She underwent 6 rounds of PEIT followed by total a parathyroidectomy with partial forearm autotransplantation. Between 2011 and 2013, surgeons removed several nodules from her pulmonary and cervical regions and the transplanted masses from her forearm; all showed hyperplasia but exhibited no histological evidence of malignancy. Damage to the parathyroid capsule after repeated PEITs may cause local cervical recurrence and pulmonary lesions, although distant lesions are extremely rare in SHPT. This case is of interest due to the possible association between PEIT and parathyromatosis and distal lesions.

  15. Shaggy Photoreceptors with Subfoveal Fluid Associated with a Distant Choroidal Melanoma

    Directory of Open Access Journals (Sweden)

    Ann Q. Tran

    2015-01-01

    Full Text Available Purpose. To describe the enhanced depth imaging optical coherence tomography (EDI-OCT findings in a patient with an extra macula choroidal melanoma before and after treatment. Methods. Observational case report. Results. A 45 year-old Caucasian male patient was referred to retina clinic for management of choroidal melanoma. Examination revealed a nasal choroidal melanoma while EDI-OCT illustrated subfoveal fluid pocket with elongated shaggy photoreceptors distant and separate from the tumor. The patient was treated with plaque brachytherapy and intravitreal bevacizumab. One week after plaque removal, there was a dramatic reduction in the shaggy photoreceptors. Conclusion. Choroidal melanomas have effects that are not localized to the area of the tumor. This loculated pocket of subretinal fluid and coinciding changes to photoreceptor morphology may be related to global changes in choroidal function or release of tumor related cytokines.

  16. Acute Reciprocal Changes Distant from the Site of Spinal Osteotomies Affect Global Postoperative Alignment

    Directory of Open Access Journals (Sweden)

    Eric Klineberg

    2011-01-01

    Full Text Available Introduction. Three-column vertebral resections are frequently applied to correct sagittal malalignment; their effects on distant unfused levels need to be understood. Methods. 134 consecutive adult PSO patients were included (29 thoracic, 105 lumbar. Radiographic analysis included pre- and postoperative regional curvatures and pelvic parameters, with paired independent t-tests to evaluate changes. Results. A thoracic osteotomy with limited fusion leads to a correction of the kyphosis and to a spontaneous decrease of the unfused lumbar lordosis (−8°. When the fusion was extended, the lumbar lordosis increased (+8°. A lumbar osteotomy with limited fusion leads to a correction of the lumbar lordosis and to a spontaneous increase of the unfused thoracic kyphosis (+13°. When the fusion was extended, the thoracic kyphosis increased by 6°. Conclusion. Data from this study suggest that lumbar and thoracic resection leads to reciprocal changes in unfused segments and requires consideration beyond focal corrections.

  17. Galaxy evolution. Quasar quartet embedded in giant nebula reveals rare massive structure in distant universe.

    Science.gov (United States)

    Hennawi, Joseph F; Prochaska, J Xavier; Cantalupo, Sebastiano; Arrigoni-Battaia, Fabrizio

    2015-05-15

    All galaxies once passed through a hyperluminous quasar phase powered by accretion onto a supermassive black hole. But because these episodes are brief, quasars are rare objects typically separated by cosmological distances. In a survey for Lyman-α emission at redshift z ≈ 2, we discovered a physical association of four quasars embedded in a giant nebula. Located within a substantial overdensity of galaxies, this system is probably the progenitor of a massive galaxy cluster. The chance probability of finding a quadruple quasar is estimated to be ∼10(-7), implying a physical connection between Lyman-α nebulae and the locations of rare protoclusters. Our findings imply that the most massive structures in the distant universe have a tremendous supply (≃10(11) solar masses) of cool dense (volume density ≃ 1 cm(-3)) gas, which is in conflict with current cosmological simulations. Copyright © 2015, American Association for the Advancement of Science.

  18. Quantum repeaters based on deterministic storage of a single photon in distant atomic ensembles

    Energy Technology Data Exchange (ETDEWEB)

    Aghamalyan, D. [Institute for Physical Research, Armenian National Academy of Sciences, Ashtarak-2 0203 (Armenia); Malakyan, Yu. [Institute for Physical Research, Armenian National Academy of Sciences, Ashtarak-2 0203 (Armenia); Centre of Strong Field Physics, Yerevan State University, 1 A. Manukian Street, Yerevan 0025 (Armenia)

    2011-10-15

    Quantum repeaters hold the promise to prevent the photon losses in communication channels. Most recently, the serious efforts have been applied to achieve scalable distribution of entanglement over long distances. However, the probabilistic nature of entanglement generation and realistic quantum memory storage times make the implementation of quantum repeaters an outstanding experimental challenge. We propose a quantum repeater protocol based on the deterministic storage of a single photon in atomic ensembles confined in distant high-finesse cavities and show that this system is capable of distributing the entanglement over long distances with a much higher rate as compared to previous protocols, thereby alleviating the limitations on the quantum memory lifetime by several orders of magnitude. Our scheme is robust with respect to phase fluctuations in the quantum channel, while the fidelity imperfection is fixed and negligibly small at each step of entanglement swapping.

  19. X makes nine: a distant ice giant in the solar system.

    Science.gov (United States)

    van den Berg, Hugo A

    2016-06-01

    Ever since Pluto lost its status as one of the main planets of our solar system and was demoted to just another frozen denizen of the Kuiper belt, we have had to make do with eight, albeit in a pleasing symmetry, with four rocky ones this side of the asteroid belt and four giants on the far side. Now it looks like number nine is back on the slate: the existence of a large planet, about ten times as massive as Earth and hundreds of times more distant from the Sun than Earth itself, has been postulated to explain the curiously bunched-up orbits of several small celestial bodies, far beyond the orbit of Neptune. To date, we have only "proof by simulation" and we are yet to observe this massive planet in the backyard of our solar system by more direct means. However, powerful new telescopes should provide visual evidence within the next few decades.

  20. Jaufré Rudel's 'love from afar' and distant love via chat; a metaphorical approach

    Directory of Open Access Journals (Sweden)

    Pau Gerez

    2006-05-01

    Full Text Available Love for an unknown person in a distant location has featured spectacularly throughout the history of literature. One of the emblematic authors who dealt with falling in love in such a blind fashion was the troubadour Jaufré Rudel, to the extent that he may be considered to be a literary paradigm. When analysing his work and its repercussions, it is impossible to escape a comparison with the type of amorous relationships that can be established via chat, the common denominator of which is that the interlocutor is unknown. In addition to the mystery, related to a high component of idealisation, we believe that there are other comparative links from a metaphorical perspective, such as distance, the identity of the participants and the specific nature of the code used. In this article, we will set out some ideas with a view to stimulating further analyses in that respect.

  1. The evolution of planetary nebulae VII. Modelling planetary nebulae of distant stellar systems

    CERN Document Server

    Schönberner, D; Sandin, C; Steffen, M

    2010-01-01

    By means of hydrodynamical models we do the first investigations of how the properties of planetary nebulae are affected by their metal content and what can be learned from spatially unresolved spectrograms of planetary nebulae in distant stellar systems. We computed a new series of 1D radiation-hydrodynamics planetary nebulae model sequences with central stars of 0.595 M_sun surrounded by initial envelope structures that differ only by their metal content. At selected phases along the evolutionary path, the hydrodynamic terms were switched off, allowing the models to relax for fixed radial structure and radiation field into their equilibrium state with respect to energy and ionisation. The analyses of the line spectra emitted from both the dynamical and static models enabled us to systematically study the influence of hydrodynamics as a function of metallicity and evolution. We also recomputed selected sequences already used in previous publications, but now with different metal abundances. These sequences w...

  2. The contribution of distant hybridization with decaploid Agropyron elongatum to wheat improvement in China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Wheat is a staple food crop in the world as well as in China. Because of the progress of wheat breeding and other agricultural sci-technologies, the wheat grain yield per unit area has increased more than five folds from 1952 to 2006 in China. The first part of this article briefly reviews the history of wheat breeding in China. Second, the establishment of "Triticum aestivum-Agropyron" distant hybridization system and its contribution to wheat production and breeding in China are summarized. Finally, the future challenges of wheat breeding are discussed, which include how to increase the utilization efficiencies of water, soil nutrient and light energy through breeding.As an example, our research progress on how to increase light use efficiency in wheat through breeding is introduced and discussed.

  3. Gas-Rich Local Dwarf Star-Forming Galaxies and their connection with the Distant Universe

    CERN Document Server

    Kunth, D

    1998-01-01

    I discuss the properties of gas-rich forming galaxies. I particularly emphasize the latest results on Lyman alpha emission that are relevant to the search of distant young galaxies. The interdependance of the Lyman alpha escape with the properties of the ISM in starburst galaxies is outlined. A new model from G. Tenorio-Tagle and his collaborators explaining Lyman alpha profiles in starburst galaxies from the hydrodynamics of superbubbles powered by massive stars is presented. I stress again that since Lyman alpha is primarely a diagnostic of the ISM, it is mandatory to understand how the ISM and Lyman alpha are related to firmly relate Lyman alpha to the cosmic star-formation rate.

  4. Gas-rich Local Dwarf Star-Forming Galaxies and Their Connection With the Distant Universe

    Science.gov (United States)

    Kunth, D.

    1999-07-01

    I discuss the properties of gas-rich forming galaxies. I particularlyemphasize the latest results on Lyα emission that are relevant to the search of distant young galaxies. The interdependance of the Lyα escape with the properties of the ISM in starburst galaxies is outlined. A new modelfrom G. Tenorio-Tagle and his collaborators explains Lyα profiles instarburst galaxies from the hydrodynamics of superbubbles powered by massivestars. I stress again that since Lyα is primarely a diagnostic ofthe ISM, it is mandatory to understand how the ISM and Lyα arerelated to firmly relate Lyα to the cosmic star-formation rate.

  5. Responses of a tall building in Los Angeles, California as inferred from local and distant earthquakes

    Science.gov (United States)

    Celebi, Mehmet; Hasan Ulusoy,; Nori Nakata,

    2016-01-01

    Increasing inventory of tall buildings in the United States and elsewhere may be subjected to motions generated by near and far seismic sources that cause long-period effects. Multiple sets of records that exhibited such effects were retrieved from tall buildings in Tokyo and Osaka ~ 350 km and 770 km from the epicenter of the 2011 Tohoku earthquake. In California, very few tall buildings have been instrumented. An instrumented 52-story building in downtown Los Angeles recorded seven local and distant earthquakes. Spectral and system identification methods exhibit significant low frequencies of interest (~0.17 Hz, 0.56 Hz and 1.05 Hz). These frequencies compare well with those computed by transfer functions; however, small variations are observed between the significant low frequencies for each of the seven earthquakes. The torsional and translational frequencies are very close and are coupled. Beating effect is observed in at least two of the seven earthquake data.

  6. Daytime Sleepiness Is Associated With Reduced Integration of Temporally Distant Outcomes on the Iowa Gambling Task.

    Science.gov (United States)

    Olson, Elizabeth A; Weber, Mareen; Rauch, Scott L; Killgore, William D S

    2016-01-01

    Sleep deprivation is associated with performance decrements on some measures of executive functioning. For instance, sleep deprivation results in altered decision making on the Iowa Gambling Task. However, it is unclear which component processes of the task may be driving the effect. In this study, Iowa Gambling task performance was decomposed using the Expectancy-Valence model. Recent sleep debt and greater daytime sleepiness were associated with higher scores on the updating parameter, which reflects the extent to which recent experiences are emphasized over remote ones. Findings suggest that the effects of insufficient sleep on IGT performance are due to shortening of the time horizon over which decisions are integrated. These findings may have clinical implications in that individuals with sleep problems may not integrate more temporally distant information when making decisions.

  7. Water-level changes induced by local and distant earthquakes at Long Valley caldera, California

    Science.gov (United States)

    Roeloffs, E.; Sneed, M.; Galloway, D.L.; Sorey, M.L.; Farrar, C.D.; Howle, J.F.; Hughes, J.

    2003-01-01

    Distant as well as local earthquakes have induced groundwater-level changes persisting for days to weeks at Long Valley caldera, California. Four wells open to formations as deep as 300 m have responded to 16 earthquakes, and responses to two earthquakes in the 3-km-deep Long Valley Exploratory Well (LVEW) show that these changes are not limited to weathered or unconsolidated near-surface rocks. All five wells exhibit water-level variations in response to earth tides, indicating they can be used as low-resolution strainmeters. Earthquakes induce gradual water-level changes that increase in amplitude for as long as 30 days, then return more slowly to pre-earthquake levels. The gradual water-level changes are always drops at wells LKT, LVEW, and CH-10B, and always rises at well CW-3. At a dilatometer just outside the caldera, earthquake-induced strain responses consist of either a step followed by a contractional strain-rate increase, or a transient contractional signal that reaches a maximum in about seven days and then returns toward the pre-earthquake value. The sizes of the gradual water-level changes generally increase with earthquake magnitude and decrease with hypocentral distance. Local earthquakes in Long Valley produce coseismic water-level steps; otherwise the responses to local earthquakes and distant earthquakes are indistinguishable. In particular, water-level and strain changes in Long Valley following the 1992 M7.3 Landers earthquake, 450 km distant, closely resemble those initiated by a M4.9 local earthquake on November 22, 1997, during a seismic swarm with features indicative of fluid involvement. At the LKT well, many of the response time histories are identical for 20 days after each earthquake, and can be matched by a theoretical solution giving the pore pressure as a function of time due to diffusion of a nearby, instantaneous, pressure drop. Such pressure drops could be produced by accelerated inflation of the resurgent dome by amounts too

  8. Quasar Quartet Embedded in Giant Nebula Reveals Rare Massive Structure in Distant Universe

    CERN Document Server

    Hennawi, Joseph F; Cantalupo, Sebastiano; Arrigoni-Battaia, Fabrizio

    2015-01-01

    All galaxies once passed through a hyperluminous quasar phase powered by accretion onto a supermassive black hole. But because these episodes are brief, quasars are rare objects typically separated by cosmological distances. In a survey for Lyman-alpha emission at redshift z ~ 2, we discovered a physical association of four quasars embedded in a giant nebula. Located within a substantial overdensity of galaxies, this system is probably the progenitor of a massive galaxy cluster. The chance probability of finding a quadruple quasar is estimated to be ~10^-7, implying a physical connection between Lyman-alpha nebulae and the locations of rare protoclusters. Our findings imply that the most massive structures in the distant universe have a tremendous supply (~ 10^11 solar masses) of cool dense (volume density ~1 cm^-3) gas, which is in conflict with current cosmological simulations.

  9. Photometry of distant clusters of galaxies: evolutionary features in the cluster 2158 + 0351 (z = 0. 45)

    Energy Technology Data Exchange (ETDEWEB)

    Molinari, E. (Milan Univ. (Italy)); Chincarini, G. (Milan Univ. (Italy) Osservatorio Astronomico di Brera, Milano (Italy)); Buzzoni, A. (Osservatorio Astronomico di Brera, Milano (Italy))

    1990-10-15

    Results of detailed three-colour photometry of the distant cluster 2158+0351 (z=0.445) are presented. A photometric catalogue has been produced using the INVENTORY package. In total we measured Gunn g, r, i magnitudes for 294 objects, down to r=23.5, with a typical error of 0.1 mag. On the basis of a statistical analysis, about 60 per cent of these are suggested to be cluster members. Luminosity functions are shown along with colour-magnitude and two-colour diagrams. We find that the bright-cluster galaxy population is dominated by ellipticals, while a population of spirals becomes relevant at the faint luminosities. Such an overabundance of faint spirals leads us to calculate a high fraction of blue objects, according to the Butcher-Oemler effect. We evidence possible photometric effects on magnitudes and colours due to galactic evolution. (author).

  10. The Physics and Mass Assembly of distant galaxies with the E-ELT

    CERN Document Server

    Puech, M; Toft, S; Cimatti, A; Neichel, B; Fusco, T

    2009-01-01

    One of the main science goal of the future European Extremely Large Telescope will be to understand the mass assembly process in galaxies as a function of cosmic time. To this aim, a multi-object, AO-assisted integral field spectrograph will be required to map the physical and chemical properties of very distant galaxies. In this paper, we examine the ability of such an instrument to obtain spatially resolved spectroscopy of a large sample of massive (0.15) redshift bin. We find that a survey of Ngal galaxies that fulfil the range of science goals can be achieved with a ~90 nights program on the E-ELT, provided a multiplex capability M Ngal/8.

  11. Interpretation of the Global Anisotropy in the Radio Polarizations of Cosmologically Distant Sources

    Indian Academy of Sciences (India)

    Pankaj Jain; S. Sarala

    2006-12-01

    We present a detailed statistical study of the observed anisotropy in radio polarizations from distant extragalactic objects. This anisotropy was earlier found by Birch (1982) and reconfirmed by Jain and Ralston (1999) in a larger data set. A very strong signal was seen after imposing the cut $|RM-\\overline{RM}| \\gt 6$ rad/m2, where RM is the rotation measure and $\\overline{RM}$ its mean value. In this paper, we show that there are several indications that this anisotropy cannot be attributed to bias in the data. We also find that a generalized statistic shows a very strong signal in the entire data without imposing the RM dependent cut. Finally we argue that an anisotropic background pseudoscalar field can explain the observations.

  12. Distant Solar System Objects identified in the Pan-STARRS1 survey

    CERN Document Server

    Weryk, R J; Chastel, S; Denneau, L; Jedicke, R; Magnier, E; Wainscoat, R J; Chambers, K; Flewelling, H; Huber, M E; Waters, C; Builders, the PS1

    2016-01-01

    We present a method to identify distant solar system objects in long-term wide-field asteroid survey data, and conduct a search for them in the Pan-STARRS1 (PS1) image data acquired from 2010 to mid-2015. We demonstrate that our method is able to find multi-opposition orbital links, and we present the resulting orbital distributions which consist of 154 Centaurs, 255 classical Trans-Neptunian Objects (TNOs), 121 resonant TNOs, 89 Scattered Disc Objects (SDOs) and 10 comets. Our results show more than half of these are new discoveries, including a newly discovered 19th magnitude TNO. Our identified objects do not show clustering in their argument of perihelia, which if present, might support the existence of a large unknown planetary-sized object in the outer solar system.

  13. Can brane dark energy model be probed observationally by distant supernovae?

    CERN Document Server

    Szydlowski, M; Szydlowski, Marek; Godlowski, Wlodzimierz

    2006-01-01

    The recent astronomical measurements of distant supernovae as well as other observations indicate that our universe is presently accelerating. There are different proposals for the explanation of this acceleration. Most of these proposals require the existence of exotic matter with negative pressure violating the strong energy condition. On the other hand, there have appeared many models which offer dramatically different mechanism for the current acceleration, in which dark energy emerges from the gravity sector rather than from the matter sector. In this paper, we compare the concordance $\\Lambda$CDM model with the braneworld models of dark energy by using Akaike and Bayesian informative critera. We show that, although this model has extra parameters (the fundamental constants of the bulk space) resulting in an improved fit to the SNIa data, these new parameters are actually not important for description of present acceleration epoch. With the example of the Sahni--Shtanov braneworld model \\cite{Shtanov03},...

  14. Organizational questions for distant trainings of health personnel at remote health units on Emergency Medicine

    Directory of Open Access Journals (Sweden)

    Orlov O.I

    2016-12-01

    Full Text Available The aim: to study possibilities of application of telemedical methods using for the organization of the system of distance learning for medical staff training in network of remote health centers with modern methods of providing emergency medical care. The use of telemedicine technology enables application of common standards of modern emergency medical care in a major industrial companies in which health care is based on the outsourcing of medical services. Technical training was implemented using a multi-point video conferencing between the head office and remote enterprises, included in its structure, implemented on the basis of corporate communications. Block-modular training infrastructure has been formed, which included both theoretical components, realized in the form of video lectures, and demonstration part including presentations, video demonstration of techniques of care. The applied technique has been realized over a short period for distant training of more than 300 health care workers providing care to 48 enterprises.

  15. Far-out thinking: generating solutions to distant analogies promotes relational thinking.

    Science.gov (United States)

    Vendetti, Michael S; Wu, Aaron; Holyoak, Keith J

    2014-04-01

    Is it possible to induce a mind-set that will affect relational thinking in a subsequent reasoning task involving unrelated materials? We investigated whether evaluating the validity of verbal analogies (Experiment 1a) or generating solutions for them (Experiment 1b) could induce a relational mind-set that would transfer to an unrelated picture-mapping task. The verbal analogies were based on either near or far semantic relations. We found that generating (but not evaluating) solutions for semantically distant analogies increased the proportion of relational mappings on the transfer task, even after we controlled for fluid intelligence and response time. Solving near analogies did not produce transfer. Generation of solutions to far analogies appears to provide a potent method for triggering a mind-set that can enhance relational thinking in a different task.

  16. The ESO Distant Cluster Sample: galaxy evolution and environment out to z=1

    CERN Document Server

    Poggianti, Bianca M; Bamford, Steven; Barazza, Fabio; Best, Philip; Clowe, Douglas; Dalcanton, Julianne; De Lucia, Gabriella; Desai, Vandana; Finn, Rose; Halliday, Claire; Jablonka, Pascale; Johnson, Olivia; Milvang-Jensen, Bo; Moustakas, John; Noll, Stefan; Nowak, Nina; Pello, Roser; Poirier, Sebastien; Rudnick, Gregory; Saglia, Roberto; Sanchez-Blazquez, Patricia; Simard, Luc; Varela, Jesus; von der Linden, Anja; Whiley, Ian; White, Simon D M; Zaritsky, Dennis

    2009-01-01

    The ESO Distant Cluster Survey (EDisCS, P.I. Simon D.M. White, LP 166.A-0162) is an ESO large programme aimed at studying clusters and cluster galaxies at z=0.4-1. How different is the evolution of the star formation activity in clusters, in groups and in the field? Does it depend on cluster mass and/or the local galaxy density? How relevant are starburst and post-starburst galaxies in the different environments? Is there an evolution in the galaxies' structures, and if so, is this related to the changes in their star formation activity? These are some of the main questions that have been investigated using the EDisCS dataset.

  17. Phylogenetic and molecular clock inferences of cyanobacterial strains within Rivulariaceae from distant environments.

    Science.gov (United States)

    Domínguez-Escobar, Julia; Beltrán, Yislem; Bergman, Birgitta; Díez, Beatriz; Ininbergs, Karolina; Souza, Valeria; Falcón, Luisa I

    2011-03-01

    Heterocyst-forming cyanobacteria are important players at both evolutionary and ecological scales, but to date it has been difficult to establish their phylogenetic affiliations. We present data from a phylogenetic and molecular clock analysis of heterocystous cyanobacteria within the family Rivulariaceae, including the genera Calothrix, Rivularia, Gloeotrichia and Tolypothrix. The strains were isolated from distant geographic regions including fresh and brackish water bodies, microbial mats from beach rock, microbialites, pebble beaches, plus PCC strains 7103 and 7504. Phylogenetic inferences (distance, likelihood and Bayesian) suggested the monophyly of genera Calothrix and Rivularia. Molecular clock estimates indicate that Calothrix and Rivularia originated ∼1500 million years ago (MYA) ago and species date back to 400-300 MYA while Tolypothrix and Gloeotrichia are younger genera (600-400 MYA).

  18. Core Needle Biopsy of Breast Cancer Tumors Increases Distant Metastases in a Mouse Model12

    Science.gov (United States)

    Mathenge, Edward Gitau; Dean, Cheryl Ann; Clements, Derek; Vaghar-Kashani, Ahmad; Photopoulos, Steffany; Coyle, Krysta Mila; Giacomantonio, Michael; Malueth, Benjamin; Nunokawa, Anna; Jordan, Julie; Lewis, John D.; Gujar, Shashi Ashok; Marcato, Paola; Lee, Patrick W.K.; Giacomantonio, Carman Anthony

    2014-01-01

    INTRODUCTION: Incisional biopsies, including the diagnostic core needle biopsy (CNB), routinely performed before surgical excision of breast cancer tumors are hypothesized to increase the risk of metastatic disease. In this study, we experimentally determined whether CNB of breast cancer tumors results in increased distant metastases and examine important resultant changes in the primary tumor and tumor microenvironment associated with this outcome. METHOD: To evaluate the effect of CNB on metastasis development, we implanted murine mammary 4T1 tumor cells in BALB/c mice and performed CNB on palpable tumors in half the mice. Subsequently, emulating the human scenario, all mice underwent complete tumor excision and were allowed to recover, with attendant metastasis development. Tumor growth, lung metastasis, circulating tumor cell (CTC) levels, variation in gene expression, composition of the tumor microenvironment, and changes in immunologic markers were compared in biopsied and non-biopsied mice. RESULTS: Mice with biopsied tumors developed significantly more lung metastases compared to non-biopsied mice. Tumors from biopsied mice contained a higher frequency of myeloid-derived suppressor cells (MDSCs) accompanied by reduced CD4 + T cells, CD8 + T cells, and macrophages, suggesting biopsy-mediated development of an increasingly immunosuppressive tumor microenvironment. We also observed a CNB-dependent up-regulation in the expression of SOX4, Ezh2, and other key epithelial-mesenchymal transition (EMT) genes, as well as increased CTC levels among the biopsy group. CONCLUSION: CNB creates an immunosuppressive tumor microenvironment, increases EMT, and facilitates release of CTCs, all of which likely contribute to the observed increase in development of distant metastases. PMID:25425969

  19. Pitch angle distributions of energetic ions in the lobes of the distant geomagnetic tail

    Energy Technology Data Exchange (ETDEWEB)

    Owen, C.J.; Cowley, S.W.H.; Richardson, I.G.; Balogh, A. (Imperial Coll. of Science and Technology, London (UK). Blackett Lab.)

    1990-07-01

    Analysis of energetic (> 35 keV) ion data from the ISEE-3 spacecraft obtained during 1982-1983, when the spacecraft made a series of traversals of the distant geomagnetic tail (X{sub GSE} > - 230 R{sub E}), indicates that the pitch angle distribution of energetic ions in the distant tail lobes is usually highly anisotropic, being peaked closely perpendicular to the magnetic field direction, but with a small net flow in the antisunward direction. In this paper we present a model, based on the motion of single particles into and within the tail lobes, which accounts for these observed distributions. This model assumes that the lobe ions originate in the magnetosheath, where the energetic ion population consists of two components; a spatially uniform ''solar'' population, and a population of ''terrestrial'' origin, which decreases in strength with downtail distance. The pitch angle distribution at any point within the lobe may be constructed, assuming that the value of the distribution function along the particle trajectory is conserved. In general, those ions with a large field-aligned component to their motion enter the lobes in the deep tail, where the ''terrestrial'' source is weak, whilst those moving closely perpendicular to the field enter the lobes at positions much closer to the Earth, where the source is strong. The fluxes of these latter ions are therefore much enhanced above the rest of the pitch angle distribution, and are shown to account for the form of the observed distributions. The model also accounts for the more isotropic ion population observed in the lobe during solar particle events, when the ''terrestrial'' component of the magnetosheath source may be considered negligible in comparison to the enhanced ''solar'' component. (author).

  20. Relationship between the inflammatory molecular profile of breast carcinomas and distant metastasis development.

    Directory of Open Access Journals (Sweden)

    Noemí Eiró

    Full Text Available Inflammatory conditions may promote tumor progression and aggressiveness. In previous reports, we found a group of breast cancer tumors characterized by metalloprotease-11 (MMP-11 expression by intratumoral mononuclear inflammatory cells (MICs, which was associated with distant metastasis development. Thus, in the present study we evaluated the relationship between MMP-11 expression by MICs, distant metastasis development, and a wide panel of inflammatory factors in breast carcinoma. In an initial approach, we analyzed 65 factors associated with tumor progression and inflammation, in a tumor population classified in good or bad prognosis, based on MMP-11 expression by intratumoral MICs. The most differentially expressed factors were then analyzed in a wider tumor population classified according to MMP-11 expression by MICs and also according to metastasis development. These analyses were carried out by Real-time PCR. The results showed that of the 65 starting factors analyzed, those related with MMP-11 expression by MICs were: IL-1, -5, -6, -8, -17, -18, MMP-1, TIMP-1, ADAM-8, -10, -15, -23, ADAMTS-1, -2, -15, Annexin A2, IFNβ, Claudin-3, CCL-3, MyD88, IRAK-4 and NFκB. Of them, factors more differentially expressed between both groups of tumors were IL-1, IL-5, IL-6, IL-17, IFNβ and NFκB. Thereafter, we confirmed in the wider tumor population, that there is a higher expression of those factors in tumors infiltrated by MMP-11 positive MICs. Altogether these results indicate that tumors developing worse prognosis and identified by MMP-11 expression by intratumoral MICs, shows an up-regulation of inflammatory-related genes.

  1. A role of aerosol particles in forming urban skyglow and skyglow from distant cities

    Science.gov (United States)

    Kocifaj, Miroslav; Kómar, Ladislav

    2016-05-01

    Aerosol particles may represent the largest uncertainty about skyglow change in many locations under clear-sky conditions. This is because aerosols are ubiquitous in the atmosphere and influence the ground-reaching radiation in different ways depending on their concentrations, origins, shapes, sizes, and compositions. Large particles tend to scatter in Fraunhofer diffraction regime, while small particles can be treated in terms of Rayleigh formalism. However, the role of particle microphysics in forming the skyglow still remains poorly quantified. We have shown in this paper that the chemistry is somehow important for backscattering from large particles that otherwise work as efficient attenuators of light pollution if composed of absorbing materials. The contribution of large particles to the urban skyglow diminishes as they become more spherical in shape. The intensity of backscattering from non-absorbing particles is more-or-less linearly decreasing function of particle radius even if number size distribution is inversely proportional to the fourth power of particle radius. This is due to single particle backscattering that generally increases steeply as the particle radius approaches large values. Forward scattering depends on the particle shape but is independent of the material composition, thus allowing for a simplistic analytical model of skyglow from distant cities. The model we have developed is based on mean value theorem for integrals and incorporates the parametrizable Garstang's emission pattern, intensity decay along optical beam path, and near-forward scattering in an atmospheric environment. Such model can be used by modellers and experimentalists for rapid estimation of skyglow from distant light sources.

  2. Observational Signatures of a Massive Distant Planet on the Scattering Disk

    Science.gov (United States)

    Lawler, S. M.; Shankman, C.; Kaib, N.; Bannister, M. T.; Gladman, B.; Kavelaars, J. J.

    2017-01-01

    The orbital element distribution of trans-Neptunian objects (TNOs) with large pericenters has been suggested to be influenced by the presence of an undetected, large planet at >200 au from the Sun. To find additional observables caused by this scenario, we present here the first detailed emplacement simulation in the presence of a massive ninth planet on the distant Kuiper Belt. We perform 4 Gyr N-body simulations with the currently known solar system planetary architecture, plus a 10 M⊕ planet with similar orbital parameters to those suggested by Trujillo & Sheppard or Batygin & Brown, and 105 test particles in an initial planetesimal disk. We find that including a distant super-Earth-mass planet produces a substantially different orbital distribution for the scattering and detached TNOs, raising the pericenters and inclinations of moderate semimajor axis (50 test whether this signature is detectable via a simulator with the observational characteristics of four precisely characterized TNO surveys. We find that the qualitatively very distinct solar system models that include a ninth planet are essentially observationally indistinguishable from an outer solar system produced solely by the four giant planets. We also find that the mass of the Kuiper Belt’s current scattering and detached populations is required to be 3–10 times larger in the presence of an additional planet. We do not find any evidence for clustering of orbital angles in our simulated TNO population. Wide-field, deep surveys targeting inclined high-pericenter objects will be required to distinguish between these different scenarios.

  3. OSSOS. V. Diffusion in the Orbit of a High-perihelion Distant Solar System Object

    Science.gov (United States)

    Bannister, Michele T.; Shankman, Cory; Volk, Kathryn; Chen, Ying-Tung; Kaib, Nathan; Gladman, Brett J.; Jakubik, Marian; Kavelaars, J. J.; Fraser, Wesley C.; Schwamb, Megan E.; Petit, Jean-Marc; Wang, Shiang-Yu; Gwyn, Stephen D. J.; Alexandersen, Mike; Pike, Rosemary E.

    2017-06-01

    We report the discovery of the minor planet 2013 SY99 on an exceptionally distant, highly eccentric orbit. With a perihelion of 50.0 au, 2013 SY99’s orbit has a semimajor axis of 730 ± 40 au, the largest known for a high-perihelion trans-Neptunian object (TNO), and well beyond those of (90377) Sedna and 2012 VP113. Yet, with an aphelion of 1420 ± 90 au, 2013 SY99’s orbit is interior to the region influenced by Galactic tides. Such TNOs are not thought to be produced in the current known planetary architecture of the solar system, and they have informed the recent debate on the existence of a distant giant planet. Photometry from the Canada-France-Hawaii Telescope, Gemini North, and Subaru indicate 2013 SY99 is ˜250 km in diameter and moderately red in color, similar to other dynamically excited TNOs. Our dynamical simulations show that Neptune’s weak influence during 2013 SY99’s perihelia encounters drives diffusion in its semimajor axis of hundreds of astronomical units over 4 Gyr. The overall symmetry of random walks in the semimajor axis allows diffusion to populate 2013 SY99’s orbital parameter space from the 1000 to 2000 au inner fringe of the Oort cloud. Diffusion affects other known TNOs on orbits with perihelia of 45 to 49 au and semimajor axes beyond 250 au. This provides a formation mechanism that implies an extended population, gently cycling into and returning from the inner fringe of the Oort cloud.

  4. Detecting remotely triggered microseismicity around Changbaishan Volcano following nuclear explosions in North Korea and large distant earthquakes around the world

    Science.gov (United States)

    Liu, Guoming; Li, Chenyu; Peng, Zhigang; Li, Xuemei; Wu, Jing

    2017-05-01

    We conduct a systematic survey on locally triggered earthquakes by large distant earthquakes in Changbaishan Volcano, an active intraplate volcano on the border between China and North Korea. We examine waveforms of distant earthquakes recorded at broadband station Changbaishan (CBS) near the volcano with estimated dynamic stresses over 5 kPa between 2000 and 2016. Out of 26 selected distant earthquakes, three of them show positive evidence of triggering during large-amplitude surface waves. The earthquakes that had positive or possible evidences of triggering generated larger long-period surface waves, indicating that they are more efficient in triggering microseismicity. In addition, since 2006 North Korea has conducted five underground nuclear explosion (UNE) tests only 140 km away from Changbaishan Volcano. By systematically examining waveforms of these UNEs recorded at station CBS, we find that none of them have triggered microearthquakes in Changbaishan Volcano.

  5. Expression of IL-1α correlates with distant metastasis in patients with head and neck squamous cell carcinoma

    Science.gov (United States)

    León, Xavier; Bothe, Carolina; García, Jacinto; Parreño, Matilde; Alcolea, Sonia; Quer, Miquel

    2015-01-01

    The presence of IL-1 in human cancers is associated with aggressive tumor biology but its prognostic value is unknown. We studied whether IL-1α expression is a prognostic marker of distant metastasis in patients with head and neck squamous cell carcinoma (HNSCC). IL-1α mRNA and protein levels were determined in tumor samples and cancer cell lines using RT-PCR and ELISA. The effects of constitutive IL-1α expression by tumor lines were characterized. IL-1α mRNA and protein secretion were higher in tumor samples from patients who later developed distant metastasis than in patients who did not. By using distant metastasis as a dependent variable, patients were classified into two categories of IL-1α transcript-levels. The high-IL-1α group had a significantly lower five-year distant metastasis-free survival than the low-IL-1α group [70.0% (CI 95%: 55.9-84.1%) vs 94.7% (CI 95%:90.2-99.2%)]. When IL-1α transcript-levels were combined with clinical factors related to tumor metastasis, the predictive power of the model increased significantly. Additionally, transcript levels of IL-1α correlated significantly with those of the IL-1 family genes and genes related to the metastatic process. IL-1 treatment of microvascular endothelial cells increased adhesion of HNSCC cells but no differences were found based on constitutive IL-1α expression by tumor cells. Nevertheless, IL-1α produced by tumor cells effectively increased their transmigration across the endothelium. We found a significant relationship between IL-1α expression and development of distant metastasis in HNSCC patients. IL-1α expression could help to define a subset of patients at high risk of distant metastasis who could benefit from adjuvant treatment. PMID:26460957

  6. Comparative study of the use of non-ionizing and ionizing radiation in the cure of epoxy resin: microwave versus electron electron

    Energy Technology Data Exchange (ETDEWEB)

    Kersting, Daniel, E-mail: daniel.kersting@usp.br [Centro Tecnologico da Marinha em Sao Paulo (CTMSP/USP), Sao Paulo, SP (Brazil); Wiebeck, Helio, E-mail: hwiebeck@usp.br [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Escola Politecnica. Dept. de Engenharia Metalurgica; Marinucci, Gerson; Silva, Leonardo G.A. e, E-mail: marinuci@ipen.br, E-mail: gasilva@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Several processes for curing epoxy resins were developed over the years. Two methods are discussed in this paper, in order to present the main advantages and disadvantages of using microwave radiation (non-ionizing radiation) and electron beam radiation (ionizing radiation). The microwave radiation is a non-ionizing radiation, with great power of penetration and transfer of heat in microwave absorbing materials, or materials with microwave absorbing fillers. The frequency usually used in research and development is 2.45 GHz, the same available in commercial equipment. The microwave effect provides increase on the collision velocity between the reactant which, combined with energy absorbed by the reaction system, accelerates the curing reaction. None modifications in the epoxy system are required to use microwave heating for the curing process.On the other hand, the electron beam is a form of ionizing radiation in which the high energy electrons have the ability to interact with the irradiated material and produce ions, free radicals, and molecules in excited state, which can be used to initiate and propagate a polymerization. Specific initiators are necessary for an effective cure of the resin. In this study, a DGEBA epoxy resin with initiators based on anhydride and amine was used under the same conditions indicated by the manufacturer. The curing of the catalyzed system was performed in a domestic microwave oven adapted for laboratory use. The degradation and glass transition temperatures were evaluated by thermal analysis techniques. For comparative purposes, it was used data available in the literature for electron beam irradiation. (author)

  7. Voyager observations in the distant heliosheath: An analogy with ISEE-3 observations in the deep geomagnetic tail

    OpenAIRE

    Richardson, Ian G.

    2016-01-01

    We suggest an analogy between energetic particle and magnetic field observations made by the Voyager 1 spacecraft in the distant heliosheath at 122 AU in August 2012, and those made in the distant geomagnetic tail by the ISEE 3 spacecraft in 1982-1983, despite large differences in the time and distance scales. The analogy suggests that in August, 2012, Voyager 1 may not have moved from the anomalous cosmic ray (ACR)-dominated heliosheath into the interstellar medium but into a region equivale...

  8. Quality of fresh retail pork cuts stored in modified atmosphere under temperature conditions simulating export to distant markets.

    Science.gov (United States)

    McMullen, L M; Stiles, M E

    1994-01-01

    The effect of storage temperature on microbial and sensory quality of retail cuts of pork was determined on samples stored under temperature regimens designed to simulate conditions that could be encountered in accessing distant markets with retail-ready product. Samples were packaged in modified atmosphere with 100% CO(2) and export of retail-ready pork cuts to distant markets with a three-week time for delivery to market at -1·5°C can be achieved with one to two weeks of marketing time at retail market at 4 to 7°C.

  9. VRML在图学教育软件中的应用技术%The Application Technology of VRML to Distant Graphic Education SoftwareC

    Institute of Scientific and Technical Information of China (English)

    温俊文; 冯开平

    2001-01-01

    With practical examples of implementation, this paper introduces the key techniques of virtual reality in simulating real scene, real-time interactive behavior and constructing interactive interface based on web. The situation that users can only do their learning by passively following the model and animation designed by the software programmer is changed. It presents a successful sample for developing the interactive distant education software of engineering graphics.%通过实例介绍虚拟现实场景模拟、实时交互行为和构建基于Web的虚拟现实交互界面等关键技术,改变以往CAI用户对软件制作者事先设计的一幅幅模型与动画,只能跟着制作者的思路进行学习的被动局面,为开发工程图学的远程教育软件提供了成功的范例。

  10. Concepts relating magnetic interactions, intertwined electronic orders, and strongly correlated superconductivity.

    Science.gov (United States)

    Davis, J C Séamus; Lee, Dung-Hai

    2013-10-29

    Unconventional superconductivity (SC) is said to occur when Cooper pair formation is dominated by repulsive electron-electron interactions, so that the symmetry of the pair wave function is other than an isotropic s-wave. The strong, on-site, repulsive electron-electron interactions that are the proximate cause of such SC are more typically drivers of commensurate magnetism. Indeed, it is the suppression of commensurate antiferromagnetism (AF) that usually allows this type of unconventional superconductivity to emerge. Importantly, however, intervening between these AF and SC phases, intertwined electronic ordered phases (IP) of an unexpected nature are frequently discovered. For this reason, it has been extremely difficult to distinguish the microscopic essence of the correlated superconductivity from the often spectacular phenomenology of the IPs. Here we introduce a model conceptual framework within which to understand the relationship between AF electron-electron interactions, IPs, and correlated SC. We demonstrate its effectiveness in simultaneously explaining the consequences of AF interactions for the copper-based, iron-based, and heavy-fermion superconductors, as well as for their quite distinct IPs.

  11. TWO DISTANT HALO VELOCITY GROUPS DISCOVERED BY THE PALOMAR TRANSIENT FACTORY

    Energy Technology Data Exchange (ETDEWEB)

    Sesar, Branimir; Cohen, Judith G.; Levitan, David; Kirby, Evan N.; Kulkarni, Shrinivas R.; Prince, Thomas A. [Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Grillmair, Carl J.; Laher, Russ R.; Surace, Jason A. [Spitzer Science Center, California Institute of Technology, Pasadena, CA 91125 (United States); Juric, Mario [Large Synoptic Survey Telescope Corp., 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Ofek, Eran O., E-mail: bsesar@astro.caltech.edu [Benoziyo Center for Astrophysics, Weizmann Institute of Science, 76100 Rehovot (Israel)

    2012-08-20

    We report the discovery of two new halo velocity groups (Cancer groups A and B) traced by eight distant RR Lyrae stars and observed by the Palomar Transient Factory survey at R.A. {approx} 129 Degree-Sign , decl. {approx} 20 Degree-Sign (l {approx} 205 Degree-Sign , b {approx} 32 Degree-Sign ). Located at 92 kpc from the Galactic center (86 kpc from the Sun), these are some of the most distant substructures in the Galactic halo known to date. Follow-up spectroscopic observations with the Palomar Observatory 5.1 m Hale telescope and W. M. Keck Observatory 10 m Keck I telescope indicate that the two groups are moving away from the Galaxy at v-bar{sub gsr}{sup A} = 78.0{+-}5.6 km s{sup -1} (Cancer group A) and v-bar{sub gsr}{sup B} = 16.3{+-}7.1 km s{sup -1} (Cancer group B). The groups have velocity dispersions of {sigma}{sub v{sub g{sub s{sub r}{sup A}}}} = 12.4{+-}5.0 km s{sup -1} and {sigma}B{sub v{sub g{sub s{sub r}{sup B}}}} =14.9{+-}6.2 km s{sup -1} and are spatially extended (about several kpc), making it very unlikely that they are bound systems, and more likely to be debris of tidally disrupted dwarf galaxies or globular clusters. Both groups are metal-poor (median metallicities of [Fe/H]{sup A} = -1.6 dex and [Fe/H]{sup B} = -2.1 dex) and have a somewhat uncertain (due to small sample size) metallicity dispersion of {approx}0.4 dex, suggesting dwarf galaxies as progenitors. Two additional RR Lyrae stars with velocities consistent with those of the Cancer groups have been observed {approx}25 Degree-Sign east, suggesting possible extension of the groups in that direction.

  12. Neuronal Heterotopias Affect the Activities of Distant Brain Areas and Lead to Behavioral Deficits.

    Science.gov (United States)

    Ishii, Kazuhiro; Kubo, Ken-ichiro; Endo, Toshihiro; Yoshida, Keitaro; Benner, Seico; Ito, Yukiko; Aizawa, Hidenori; Aramaki, Michihiko; Yamanaka, Akihiro; Tanaka, Kohichi; Takata, Norio; Tanaka, Kenji F; Mimura, Masaru; Tohyama, Chiharu; Kakeyama, Masaki; Nakajima, Kazunori

    2015-09-01

    Neuronal heterotopia refers to brain malformations resulting from deficits of neuronal migration. Individuals with heterotopias show a high incidence of neurological deficits, such as epilepsy. More recently, it has come to be recognized that focal heterotopias may also show a range of psychiatric problems, including cognitive and behavioral impairments. However, because focal heterotopias are not always located in the brain areas responsible for the symptoms, the causal relationship between the symptoms and heterotopias remains elusive. In this study, we showed that mice with focal heterotopias in the somatosensory cortex generated by in utero electroporation exhibited spatial working memory deficit and low competitive dominance behavior, which have been shown to be closely associated with the activity of the medial prefrontal cortex (mPFC) in rodents. Analysis of the mPFC activity revealed that the immediate-early gene expression was decreased and the local field potentials of the mPFC were altered in the mice with heterotopias compared with the control mice. Moreover, activation of these ectopic and overlying sister neurons using the DREADD (designer receptor exclusively activated by designer drug) system improved the working memory deficits. These findings suggest that cortical regions containing focal heterotopias can affect distant brain regions and give rise to behavioral abnormalities. Significance statement: Recent studies reported that patients with heterotopias have a variety of clinical symptoms, such as cognitive disturbance, psychiatric symptoms, and autistic behavior. However, the causal relationship between the symptoms and heterotopias remains elusive. Here we showed that mice with focal heterotopias in the somatosensory cortex generated by in utero electroporation exhibited behavioral deficits that have been shown to be associated with the mPFC activity in rodents. The existence of heterotopias indeed altered the neural activities of the mPFC, and

  13. Corralling a distant unseen planet with extreme resonant Kuiper belt objects

    Science.gov (United States)

    Malhotra, Renu; Volk, Kathryn; Wang, Xianyu

    2016-10-01

    Several recent studies have appealed to the clustering of the angular orbital elements of very distant, extreme Kuiper belt objects (eKBOs) to argue for the existence of a large planet in the distant solar system. We identify other properties of eKBOs that may support the existence of such an unseen planet. We observe that several eKBOs have orbital periods close to integer ratios with each other. These would be dynamically significant only if the eKBOs are in mean motion resonances (MMRs) with an unseen massive planet. If such MMRs are true, then their resonant dynamics can provide constraints on the planet's parameters and its current location in its orbital path. We calculate that a hypothetical planet with orbital period ~17,117 years (semimajor axis ~665 AU), could have small integer period ratios (of the form N/1 or N/2) with the four longest period eKBOs. Our calculations suggest two possibilities for the planet's orbit plane: a plane moderately close to the ecliptic (i~18°) or an inclined plane (i~48°). The former offers dynamical stability of the high-eccentricity eKBOs by means of libration of the relative longitudes, and the latter offers enhanced dynamical stability by means of additional libration of the argument of perihelion, ω. Standard theory of MMRs breaks down for the extremely high orbital eccentricities (~0.7-0.9) of the eKBOs. We developed asymptotic analytical approximations, supported by numerical analysis of the circular restricted three body problem, to estimate that a planet of mass >~10 M♀ has MMR widths large enough that the current orbital uncertainties of the eKBOs allow libration in the hypothesized MMRs, as well as libration of ω in the inclined planet case. Our calculations indicate that the planet's orbital eccentricity is unlikely to exceed ~0.3 for stable resonant librations of the eKBOs. Libration of critical resonant angles of the hypothesized MMRs of the eKBOs define exclusion zones of the current location of the planet

  14. Comprehensive transcriptome analysis using synthetic long-read sequencing reveals molecular co-association of distant splicing events.

    Science.gov (United States)

    Tilgner, Hagen; Jahanbani, Fereshteh; Blauwkamp, Tim; Moshrefi, Ali; Jaeger, Erich; Chen, Feng; Harel, Itamar; Bustamante, Carlos D; Rasmussen, Morten; Snyder, Michael P

    2015-07-01

    Alternative splicing shapes mammalian transcriptomes, with many RNA molecules undergoing multiple distant alternative splicing events. Comprehensive transcriptome analysis, including analysis of exon co-association in the same molecule, requires deep, long-read sequencing. Here we introduce an RNA sequencing method, synthetic long-read RNA sequencing (SLR-RNA-seq), in which small pools (≤1,000 molecules/pool, ≤1 molecule/gene for most genes) of full-length cDNAs are amplified, fragmented and short-read-sequenced. We demonstrate that these RNA sequences reconstructed from the short reads from each of the pools are mostly close to full length and contain few insertion and deletion errors. We report many previously undescribed isoforms (human brain: ∼13,800 affected genes, 14.5% of molecules; mouse brain ∼8,600 genes, 18% of molecules) and up to 165 human distant molecularly associated exon pairs (dMAPs) and distant molecularly and mutually exclusive pairs (dMEPs). Of 16 associated pairs detected in the mouse brain, 9 are conserved in human. Our results indicate conserved mechanisms that can produce distant but phased features on transcript and proteome isoforms.

  15. Metastasectomy for Distant Metastatic Melanoma : Analysis of Data from the First Multicenter Selective Lymphadenectomy Trial (MSLT-I)

    NARCIS (Netherlands)

    Howard, J. Harrison; Thompson, John F.; Mozzillo, Nicola; Nieweg, Omgo E.; Hoekstra, Harald J.; Roses, Daniel F.; Sondak, Vernon K.; Reintgen, Douglas S.; Kashani-Sabet, Mohammed; Karakousis, Constantine P.; Coventry, Brendon J.; Kraybill, William G.; Smithers, B. Mark; Elashoff, Robert; Stern, Stacey L.; Cochran, Alistair J.; Faries, Mark B.; Morton, Donald L.

    2012-01-01

    For stage IV melanoma, systemic medical therapy (SMT) is used most frequently; surgery is considered an adjunct in selected patients. We retrospectively compared survival after surgery with or without SMT versus SMT alone for melanoma patients developing distant metastases while enrolled in the firs

  16. Omentum: An unusual site for distant metastasis for post-surgery radiotherapy treated squamous cell carcinoma larynx

    Directory of Open Access Journals (Sweden)

    Tamalika Kundu

    2016-01-01

    Full Text Available Squamous cell carcinoma of the larynx is the most common histologic type, accounting for up to 90% of cancers with more predilections to spread locoregionally to the cervical lymph nodes. Distant metastasis, usually to lungs, bone, and liver is seen much less frequently, with an overall incidence of 6.5–7.3%. A case of 55-year-old male with the previous history of surgery and radiotherapy treated squamous cell carcinoma of the larynx, presenting with a chief complaint of pain abdomen is hereby reported for its unusual diagnosis of metastatic deposits of squamous cell carcinoma in the omentum. Though there are reference available for peritoneum as the distant metastatic site for hypopharyngeal carcinoma, reference for laryngeal carcinoma metastasizing to omentum were not found even with an extensive search of literature. Awareness of unusual sites of distant metastasis such as omentum must be kept in mind for treated laryngeal carcinoma patients presenting with non-specific symptoms like pain abdomen. And also, chances of involvement of unusual site of the distant metastasis increases with advanced tumor-node-metastasis stage and nodal status.

  17. Information and Communication Technology Skills of Students Using the Distant Education Management System to Complete Their Theology Undergraduate Education

    Science.gov (United States)

    Yalman, Murat; Basaran, Bulent; Gonen, Selehattin

    2016-01-01

    Considering several variables, the present study aimed at examining the information and communication technology skills of university students taking their courses with the distant education system. In the study, the singular and relational survey model, one of general survey models, was used. The research sample was made up of 381 students…

  18. When curiosity kills no cat - but mediates the relation between distant future thoughts and global processing across sensory modalities

    NARCIS (Netherlands)

    Förster, J.; Becker, D.

    2012-01-01

    Four studies examined the effect of primed temporal distance on global versus local perception, using auditory, haptic, gustatory, and olfactory stimuli. The studies show that thinking of the more distant (versus proximal) future facilitated Gestalt perception and impaired perception of details acro

  19. Study of Co-Located and Distant Collaboration with Symbolic Support via a Haptics-Enhanced Virtual Reality Task

    Science.gov (United States)

    Yeh, Shih-Ching; Hwang, Wu-Yuin; Wang, Jin-Liang; Zhan, Shi-Yi

    2013-01-01

    This study intends to investigate how multi-symbolic representations (text, digits, and colors) could effectively enhance the completion of co-located/distant collaborative work in a virtual reality context. Participants' perceptions and behaviors were also studied. A haptics-enhanced virtual reality task was developed to conduct…

  20. Bethe-Heitler cascades as a plausible origin of hard spectra in distant TeV blazars

    CERN Document Server

    Zheng, Y G; Kang, S J

    2016-01-01

    Context. Very high-energy (VHE) $\\gamma$-ray measurements of distant TeV blazars can be nicely explained by TeV spectra induced by ultra high-energy cosmic rays. Aims. We develop a model for a plausible origin of hard spectra in distant TeV blazars. Methods. In the model, the TeV emission in distant TeV blazars is dominated by two mixed components. The first is the internal component with the photon energy around 1 TeV produced by inverse Compton scattering of the relativistic electrons on the synchrotron photons (SSC) with a correction for extragalactic background light absorbtion and the other is the external component with the photon energy more than 1 TeV produced by the cascade emission from high-energy protons propagating through intergalactic space. Results. Assuming suitable model parameters, we apply the model to observed spectra of distant TeV blazars of 1ES 0229+200. Our results show that 1) the observed spectrum properties of 1ES 0229+200, especially the TeV $\\gamma$-ray tail of the observed spect...

  1. The opacity of Spiral Disks IV : Radial Extinction Profiles from Counts of Distant Galaxies seen through Foreground Disks

    NARCIS (Netherlands)

    Holwerda, B. W.; González, R. A.; Allen, R. J.; Kruit, P.C. van der

    2004-01-01

    Dust extinction can be determined from the number of distant field galaxies seen through a spiral disk. To calibrate this number for the crowding and confusion introduced by the foreground image, Gonzalez et al. (1998) and Holwerda et al. (2005a) developed the ``Synthetic Field Method'' (SFM), which

  2. The opacity of spiral galaxy disks. IV. Radial extinction profiles from counts of distant galaxies seen through foreground disks

    NARCIS (Netherlands)

    Holwerda, BW; Gonzalez, RA; Allen, RJ; van der Kruit, PC

    2005-01-01

    Dust extinction can be determined from the number of distant field galaxies seen through a spiral disk. To calibrate this number for the crowding and confusion introduced by the foreground image, Gonzalez et al. and Holwerda et al. developed the Synthetic Field Method (SFM), which analyzes synthetic

  3. Study of Co-Located and Distant Collaboration with Symbolic Support via a Haptics-Enhanced Virtual Reality Task

    Science.gov (United States)

    Yeh, Shih-Ching; Hwang, Wu-Yuin; Wang, Jin-Liang; Zhan, Shi-Yi

    2013-01-01

    This study intends to investigate how multi-symbolic representations (text, digits, and colors) could effectively enhance the completion of co-located/distant collaborative work in a virtual reality context. Participants' perceptions and behaviors were also studied. A haptics-enhanced virtual reality task was developed to conduct…

  4. Four-terminal resistance of an interacting quantum wire with weakly invasive contacts

    OpenAIRE

    Aita, Hugo; Arrachea, Liliana; Naón, Carlos

    2011-01-01

    We analyze the behavior of the four-terminal resistance, relative to the two-terminal resistance of an interacting quantum wire with an impurity, taking into account the invasiveness of the voltage probes. We consider a one-dimensional Luttinger model of spinless fermions for the wire. We treat the coupling to the voltage probes perturbatively, within the framework of non-equilibrium Green function techniques. Our investigation unveils the combined effect of impurities, electron-electron inte...

  5. Structural and dynamical aspects of the distant magnetotail determined from ISEE-3 plasma measurements

    Energy Technology Data Exchange (ETDEWEB)

    Hones, E.W.; Zwicki, R.D.; Fritz, T.A.; Bame, S.J.

    1986-10-01

    Large lateral displacements of the magnetotail at ISEE-3 orbital distances can result from the angular variations of solar wind flow that occur frequently. To determine the tail's shape and structure from the ISEE-3 measurements it is desirable to determine quantitatively the tail's displacement during such measurements. Three-dimensional solar wind measurements by IMP-8 have been used together with a new coordinate system, the Geocentric Solar Wind (GSW) system, which reflects solar wind direction changes (as well as earth dipole motion), to estimate the location of ISEE-3 within the tail cross-section. Preliminary tests suggest that at least those changes of satellite location within the tail resulting from long term (few hour) solar wind changes can be determined by the method. Energetic ion spectra, measured in plasmoids by ISEE-3 in the distant tail and by ISEE-2 at the time of the plasmoid's departure from the near tail, have the same exponential form, distinctly different from the power law form that has earlier been ascribed to plasma sheet ion spectra. The ions are trapped in the closed loops of the plasmoid and the major anisotropy that they show is due to their convective motion with the moving plasmoid, not to field-aligned streaming.

  6. A close-pair binary in a distant triple supermassive black hole system.

    Science.gov (United States)

    Deane, R P; Paragi, Z; Jarvis, M J; Coriat, M; Bernardi, G; Fender, R P; Frey, S; Heywood, I; Klöckner, H-R; Grainge, K; Rumsey, C

    2014-07-03

    Galaxies are believed to evolve through merging, which should lead to some hosting multiple supermassive black holes. There are four known triple black hole systems, with the closest black hole pair being 2.4 kiloparsecs apart (the third component in this system is at 3 kiloparsecs), which is far from the gravitational sphere of influence (about 100 parsecs for a black hole with mass one billion times that of the Sun). Previous searches for compact black hole systems concluded that they were rare, with the tightest binary system having a separation of 7 parsecs (ref. 10). Here we report observations of a triple black hole system at redshift z = 0.39, with the closest pair separated by about 140 parsecs and significantly more distant from Earth than any other known binary of comparable orbital separation. The effect of the tight pair is to introduce a rotationally symmetric helical modulation on the structure of the large-scale radio jets, which provides a useful way to search for other tight pairs without needing extremely high resolution observations. As we found this tight pair after searching only six galaxies, we conclude that tight pairs are more common than hitherto believed, which is an important observational constraint for low-frequency gravitational wave experiments.

  7. A distant cis acting intronic element induces site-selective RNA editing

    DEFF Research Database (Denmark)

    Daniel, Chammiran; Venø, Morten Trillingsgaard; Ekdahl, Ylva

    2012-01-01

    Transcripts have been found to be site selectively edited from adenosine-to-inosine (A-to-I) in the mammalian brain, mostly in genes involved in neurotransmission. While A-to-I editing occurs at double-stranded structures, other structural requirements are largely unknown. We have investigated...... the requirements for editing at the I/M site in the Gabra-3 transcript of the GABA(A) receptor. We identify an evolutionarily conserved intronic duplex, 150 nt downstream of the exonic hairpin where the I/M site resides, which is required for its editing. This is the first time a distant RNA structure has been...... shown to be important for A-to-I editing. We demonstrate that the element also can induce editing in related but normally not edited RNA sequences. In human, thousands of genes are edited in duplexes formed by inverted repeats in non-coding regions. It is likely that numerous such duplexes can induce...

  8. Comparative molecular analysis of evolutionarily distant glyceraldehyde-3-phosphate dehydrogenase from Sardina pilchardus and Octopus vulgaris.

    Science.gov (United States)

    Baibai, Tarik; Oukhattar, Laila; Mountassif, Driss; Assobhei, Omar; Serrano, Aurelio; Soukri, Abdelaziz

    2010-12-01

    The NAD(+)-dependent cytosolic glyceraldehyde-3-phosphate dehydrogenase (GAPDH, EC 1.2.1.12), which is recognized as a key to central carbon metabolism in glycolysis and gluconeogenesis and as an important allozymic polymorphic biomarker, was purified from muscles of two marine species: the skeletal muscle of Sardina pilchardus Walbaum (Teleost, Clupeida) and the incompressible arm muscle of Octopus vulgaris (Mollusca, Cephalopoda). Comparative biochemical studies have revealed that they differ in their subunit molecular masses and in pI values. Partial cDNA sequences corresponding to an internal region of the GapC genes from Sardina and Octopus were obtained by polymerase chain reaction using degenerate primers designed from highly conserved protein motifs. Alignments of the deduced amino acid sequences were used to establish the 3D structures of the active site of two enzymes as well as the phylogenetic relationships of the sardine and octopus enzymes. These two enzymes are the first two GAPDHs characterized so far from teleost fish and cephalopod, respectively. Interestingly, phylogenetic analyses indicated that the sardina GAPDH is in a cluster with the archetypical enzymes from other vertebrates, while the octopus GAPDH comes together with other molluscan sequences in a distant basal assembly closer to bacterial and fungal orthologs, thus suggesting their different evolutionary scenarios.

  9. The Damage Capacity of Mahanarva spectabilis (Distant, 1909 (Hemiptera: Cercopidae Adults on Brachiaria ruziziensis Pasture

    Directory of Open Access Journals (Sweden)

    Tiago Teixeira Resende

    2013-01-01

    Full Text Available The aim of this study was to determine the damage caused by adult Mahanarva spectabilis (Distant, 1909 (Hemiptera: Cercopidae on Brachiaria ruziziensis (Germain & Evard under field conditions. A total of 0, 4, 8, 12, or 16 M. spectabilis adults per plot were maintained for 6 days. Thereafter, the insects were removed from the plant, and the following parameters were evaluated: chlorophyll content, damage score, dry as well as fresh weights, percentage of shoots’ dry matter, and the forage’s ability to regrow. The chlorophyll content was significantly reduced; the damage score and percentage of dry matter in plants increased depending on the increased insect infestation density after 6 days of exposure. In contrast, no change was observed on the B. ruziziensis fresh and dry weights as well as the regrowth capacity depending on the M. spectabilis infestation densities. Attacks by 8 adult M. spectabilis per clump of B. ruziziensis with an average of 80 tillers for 6 days were sufficient to reduce the chlorophyll content and the functional plant loss index. This density can be a reference for spittlebug integrated management in Brachiaria.

  10. Distant Retrograde Orbits for space-based Near Earth Objects detection

    Science.gov (United States)

    Stramacchia, Michele; Colombo, Camilla; Bernelli-Zazzera, Franco

    2016-09-01

    We analyse a concept for the detection of Potentially Hazardous Asteroids (PHAs) from a space-based network of telescopes on retrograde Distant Periodic Orbits. Planar periodic orbits are designed in the Sun-Earth circular restricted three-body problem, starting from initial conditions in the Hill's problem available from the literature. A family of retrograde orbits centred at the Earth is selected as baseline, based on their maximum distance from Earth, larger than the Earth-L2 distance. Indeed, spacecraft on such orbits can detect PHAs incoming from the Sun direction, which could not otherwise be monitored from current Earth-based systems. A trade-off on the orbit amplitude, asteroid diameter to be detected, and the constellation size is performed considering current visible sensor telescope technology. The Chelyabinsk meteor scenario is studied and the potential warning time that could be gained with a space-based survey system with respect to an Earth based-survey system is shown.

  11. DISCOVERY OF THREE DISTANT, COLD BROWN DWARFS IN THE WFC3 INFRARED SPECTROSCOPIC PARALLELS SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Masters, D.; Siana, B. [Department of Physics and Astronomy, University of California, Riverside, CA 92521 (United States); McCarthy, P.; Hathi, N. P.; Dressler, A. [Observatories of the Carnegie Institution of Washington, Pasadena, CA 91101 (United States); Burgasser, A. J. [Center for Astrophysics and Space Science, University of California, San Diego, La Jolla, CA 92093 (United States); Malkan, M.; Ross, N. R. [Department of Physics and Astronomy, UCLA, Los Angeles, CA 90095 (United States); Scarlata, C. [Astronomy Department, University of Minnesota, Minneapolis, MN 55455 (United States); Henry, A. [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Colbert, J.; Atek, H. [Spitzer Science Center, Caltech, Pasadena, CA 91125 (United States); Rafelski, M.; Teplitz, H. [Infrared Processing and Analysis Center, Caltech, Pasadena, CA 91125 (United States); Bunker, A. [Department of Physics, University of Oxford, Oxford (United Kingdom)

    2012-06-10

    We present the discovery of three late-type ({>=}T4.5) brown dwarfs, including a probable Y dwarf, in the WFC3 Infrared Spectroscopic Parallels (WISP) survey. We use the G141 grism spectra to determine the spectral types of the dwarfs and derive distance estimates based on a comparison with nearby T dwarfs with known parallaxes. These are the most distant spectroscopically confirmed T/Y dwarfs, with the farthest at an estimated distance of {approx}400 pc. We compare the number of cold dwarfs found in the WISP survey with simulations of the brown dwarf mass function. The number found is generally consistent with an initial stellar mass function dN/dM{proportional_to}M{sup -{alpha}} with {alpha} = 0.0-0.5, although the identification of a Y dwarf is somewhat surprising and may be indicative of either a flatter absolute magnitude/spectral-type relation than previously reported or an upturn in the number of very-late-type brown dwarfs in the observed volume.

  12. Discovery of Three Distant, Cold Brown Dwarfs in the WFC3 Infrared Spectroscopic Parallels Survey

    CERN Document Server

    Masters, Daniel; Burgasser, Adam J; Hathi, Nimish P; Malkan, Matthew; Ross, Nathaniel R; Siana, Brian; Scarlata, Claudia; Henry, Alaina; Colbert, James; Atek, Hakim; Rafelski, Marc; Teplitz, Harry; Bunker, Andrew; Dressler, Alan

    2012-01-01

    We present the discovery of three late type (>T4) brown dwarfs, including a probable Y dwarf, in the WFC3 Infrared Spectroscopic Parallels (WISP) Survey. We use the G141 grism spectra to determine the spectral types of the dwarfs and derive distance estimates based on a comparison with nearby T dwarfs with known parallaxes. These are the most distant spectroscopically confirmed T/Y dwarfs, with the farthest at an estimated distance of ~400 pc. We compare the number of cold dwarfs found in the WISP survey with simulations of the brown dwarf mass function. The number found is generally consistent with an initial stellar mass function dN/dM \\propto M^{-\\alpha} with \\alpha = 0.0--0.5, although the identification of a Y dwarf is somewhat surprising and may be indicative of either a flatter absolute magnitude/spectral type relation than previously reported or an upturn in the number of very late type brown dwarfs in the observed volume.

  13. Long-Term X-ray Variability of Typical Active Galactic Nuclei in the Distant Universe

    CERN Document Server

    Yang, G; Luo, B; Xue, Y; Bauer, F; Sun, M; Kim, S; Schulze, S; Zheng, X; Paolillo, M; Shemmer, O; Liu, T; Schneider, D; Vignali, C; Vito, F; Wang, J -X

    2016-01-01

    We perform long-term ($\\approx 15$ yr, observed-frame) X-ray variability analyses of the 68 brightest radio-quiet active galactic nuclei (AGNs) in the 6 Ms $Chandra$ Deep Field-South (CDF-S) survey; the majority are in the redshift range of $0.6-3.1$, providing access to penetrating rest-frame X-rays up to $\\approx 10-30$ keV. Twenty-four of the 68 sources are optical spectral type I AGNs, and the rest (44) are type II AGNs. The time scales probed in this work are among the longest for X-ray variability studies of distant AGNs. Photometric analyses reveal widespread photon-flux variability: $90\\%$ of AGNs are variable above a 95% confidence level, including many X-ray obscured AGNs and several optically classified type II quasars. We characterize the intrinsic X-ray luminosity ($L_{\\rm{X}}$) and absorption ($N_{\\rm{H}}$) variability via spectral fitting. Most (74%) sources show $L_{\\rm{X}}$ variability; the variability amplitudes are generally smaller for quasars. A Compton-thick candidate AGN shows variabili...

  14. Non-invasive brain stimulation in neurorehabilitation: local and distant effects for motor recovery.

    Science.gov (United States)

    Liew, Sook-Lei; Santarnecchi, Emilliano; Buch, Ethan R; Cohen, Leonardo G

    2014-01-01

    Non-invasive brain stimulation (NIBS) may enhance motor recovery after neurological injury through the causal induction of plasticity processes. Neurological injury, such as stroke, often results in serious long-term physical disabilities, and despite intensive therapy, a large majority of brain injury survivors fail to regain full motor function. Emerging research suggests that NIBS techniques, such as transcranial magnetic (TMS) and direct current (tDCS) stimulation, in association with customarily used neurorehabilitative treatments, may enhance motor recovery. This paper provides a general review on TMS and tDCS paradigms, the mechanisms by which they operate and the stimulation techniques used in neurorehabilitation, specifically stroke. TMS and tDCS influence regional neural activity underlying the stimulation location and also distant interconnected network activity throughout the brain. We discuss recent studies that document NIBS effects on global brain activity measured with various neuroimaging techniques, which help to characterize better strategies for more accurate NIBS stimulation. These rapidly growing areas of inquiry may hold potential for improving the effectiveness of NIBS-based interventions for clinical rehabilitation.

  15. Swift observations of GRB050904: the most distant cosmic explosion ever observed

    CERN Document Server

    Cusumano, G; Chincarini, G; Panaitescu, A; Burrows, D N; La Parola, V; Sakamoto, T; Campana, S; Mineo, T; Tagliaferri, G; Angelini, L; Barthelemy, S D; Beardmore, A P; Boyd, P T; Cominsky, L; Gronwall, C; Fenimore, E E; Gehrels, N; Giommi, P; Goad, M; Hurley, K; Immler, S; Kennea, J A; Mason, K O; Marshall, F; Mészáros, P; Nousek, J A; Osborne, J P; Palmer, D M; Roming, P W A; Wells, A; White, N E; Zhang, B

    2006-01-01

    Swift discovered the high redshift (z=6.29) GRB050904 with the Burst Alert Telescope (BAT) and began observing with its narrow field instruments 161 s after the burst onset. This gamma-ray burst is the most distant cosmic explosion ever observed. Because of its high redshift, the X-ray Telescope (XRT) and BAT simultaneous observations provide 4 orders of magnitude of spectral coverage (0.2-150 keV; 1.4-1090 keV in the source rest frame) at a very early source-frame time (22 s). GRB050904 was a long, multi-peaked, bright GRB with strong variability during its entire evolution. The light curve observed by the XRT is characterized by the presence of a long flaring activity lasting up to 1-2 hours after the burst onset in the burst rest frame, with no evidence of a smooth power-law decay following the prompt emission as seen in other GRBs. However, the BAT tail extrapolated to the XRT band joins the XRT early light curve and the overall behavior resembles that of a very long GRB prompt. The spectral energy distri...

  16. Similar lymphocytic infiltration pattern in primary breast cancer and their corresponding distant metastases.

    Science.gov (United States)

    Sobottka, Bettina; Pestalozzi, Bernhard; Fink, Daniel; Moch, Holger; Varga, Zsuzsanna

    2016-06-01

    Tumor infiltrating lymphocytes in primary breast cancer (TIL) are acknowledged measures of disease free survival (DFS) in adjuvant and neoadjuvant settings. Little is known about the biology of metastasis infiltrating lymphocytes (mTIL) although the local immunity of the metastatic site may critically influence the infiltrate composite. To address this question, we compared mTIL with their matched TIL in 87 breast cancer patients and their corresponding distant metastasis at four different anatomical locations. Sections of surgical specimen were immunohistochemically analyzed for CD4(+), CD8(+) and CD20(+) lymphocytes in three different tumor compartments: intratumoral lymphocytes (iTIL) defined as lymphocytes in direct contact with breast cancer cells, stromal lymphocytes (sTIL) located within the intratumoral stromal tissue and invasive-margin lymphocytes (imTIL). Overall, we found fewer (p iTIL both within metastases and the matched primary tumors (PT) (p < 0.001). CD4(+) T cells were more numerous than CD8(+) T cells and CD20(+) B cells (p < 0.001). There was a similar pattern in PT and their corresponding metastasis. Only patients with brain metastases differed from the others displaying less CD20(+) B cells at the infiltrative margin of the PT (p < 0.05). In summary, mTIL were significantly reduced within metastases but still mirrored the infiltrate pattern of the PT, interestingly regardless of the metastatic anatomical locations investigated. Our results suggest that the PT assigns the infiltrating lymphocyte pattern resumed at the metastatic site.

  17. Strangers on the Doorstep: Hostility and Hospitality in A Distant Shore

    Directory of Open Access Journals (Sweden)

    Lin Ching-Huan

    2016-12-01

    Full Text Available This article focuses on the rising hostility against immigrants / refugees and growing demand for hospitality, in both regional and transnational senses, in Caryl Phillips’s novel A Distant Shore, set in a local place in North England. I think that the author, in examining the parallel conditions of being a stranger in a village and an outsider to the nation, shows that the demands of hospitality are similarly urgent whether sought by nationals or foreigners though these are calibrated differently in terms of scales of belonging. My broader argument is that hospitality is an ethical practice of everyday life that requires continual renegotiation. Inspired by Levinasian ethics, I turn to Derrida’s and Rosello’s meditations on hospitality, which emphasise the metaphorical nature of the host-guest relationship and the tension it inscribes between the finiteness of politics and the infinity of ethics. By exploring the complex relationship between politics and ethics as this is made manifest in the literary representations of ordinary British citizens’ everyday practices, I suggest that this novel not only deals with the UK’s domestic tensions of multiculturalism and ethnic conflict, but also critically reflects on its bewildered (but hardly new attitude toward the ongoing transnational integration of the new Europe in the postwar period.

  18. Physical properties of distant red galaxies in the COSMOS/UltraVISTA field

    CERN Document Server

    Ma, Zhongyang; Kong, Xu; Fan, Lulu

    2015-01-01

    We present a study on physical properties for a large distant red galaxy (DRG) sample, using the $K$-selected multi-band photometry catalog of the COSMOS/UltraVISTA field and the CANDELS NIR data. Our sample includes 4485 DRGs with $(J-K)_\\mathrm{AB}>1.16$ and $K_\\mathrm{AB}<$23.4 mag, and 132 DRGs have HST/WFC3 morphological measurements. The results of nonparametric measurements of DRG morphology are consistent with our rest-frame UVJ color classification: quiescent DRGs are generally compact while star-forming DRGs tend to have extended structures. We find the star formation rate (SFR) and the stellar mass of star-forming DRGs present tight "main sequence" relations in all redshift bins. Moreover, the specific SFR (sSFR) of DRGs increase with redshift in all stellar mass bins and DRGs with higher stellar masses generally have lower sSFRs, which indicates that galaxies were much more active on average in the past, and star formation contributes more to the mass growth of low-mass galaxies than to high-ma...

  19. Cerebellum as Initial Site of Distant Metastasis from Papillary Carcinoma of Thyroid: Review of Three Cases

    Directory of Open Access Journals (Sweden)

    Mutahir A. Tunio

    2015-01-01

    Full Text Available Background. The cerebellum as initial site of distant metastasis from differentiated thyroid carcinoma (DTC including papillary (PTC and follicular thyroid carcinoma (FTC is rare manifestation. Case Presentations. Herein, we present three cases of cerebellar metastasis (CBM of PTC. Mean age of patients was 67 years (range: 64–72, and mean duration between initial diagnosis and CBM was 49.6 months (range: 37–61. Frequent location was left cerebellar hemisphere and was associated with hydrocephalus. All patients underwent suboccipital craniectomy, and in two patients postoperative intensity modulated radiation therapy (IMRT was given to deliver 5000 cGy in 25 fractions to residual lesions. Patient without postoperative IMRT had cerebellar recurrence along with lung and bone metastasis after 38 months. However, two patients were found alive and free of disease at the time of last follow-up. Conclusion. CBM from PTC is a rare clinical entity and is often associated with hydrocephalus. Histopathological diagnosis is important to initiate effective treatment, which relies on multidisciplinary approach to prolong the disease-free and overall survival rates.

  20. Connecting the Interstellar Gas and Dust Properties in Distant Galaxies Using Quasar Absorption Systems

    Science.gov (United States)

    Aller, Monique C.; Dwek, Eliahu; Kulkarni, Varsha P.; York, Donald G.; Welty, Daniel E.; Vladilo, Giovanni; Som, Debopam; Lackey, Kyle; Dwek, Eli; Beiranvand, Nassim; hide

    2016-01-01

    Gas and dust grains are fundamental components of the interstellar medium and significantly impact many of the physical processes driving galaxy evolution, such as star-formation, and the heating, cooling, and ionization of the interstellar material. Quasar absorption systems (QASs), which trace intervening galaxies along the sightlines to luminous quasars, provide a valuable tool to directly study the properties of the interstellar gas and dust in distant, normal galaxies. We have established the presence of silicate dust grains in at least some gas-rich QASs, and find that they exist at higher optical depths than expected for diffuse gas in the Milky Way. Differences in the absorption feature shapes additionally suggest variations in the silicate dust grain properties, such as in the level of grain crystallinity, from system-to-system. We present results from a study of the gas and dust properties of QASs with adequate archival IR data to probe the silicate dust grain properties. We discuss our measurements of the strengths of the 10 and 18 micron silicate dust absorption features in the QASs, and constraints on the grain properties (e.g., composition, shape, crystallinity) based on fitted silicate profile templates. We investigate correlations between silicate dust abundance, reddening, and gas metallicity, which will yield valuable insights into the history of star formation and chemical enrichment in galaxies.

  1. Internal kinematics of spiral galaxies in distant clusters III. Velocity fields from FORS2/MXU spectroscopy

    CERN Document Server

    Kutdemir, E; Peletier, R F; Da Rocha, C; Kronberger, T; Kapferer, W; Schindler, S; Böhm, A; Jäger, K; Kuntschner, Harald; Verdugo, M

    2008-01-01

    (Abridged) We study the impact of cluster environment on the evolution of spiral galaxies by examining their structure and kinematics. Rather than two-dimensional rotation curves, we observe complete velocity fields by placing three adjacent and parallel FORS2 MXU slits on each object, yielding several emission and absorption lines. The gas velocity fields are reconstructed and decomposed into circular rotation and irregular motions using kinemetry. To quantify irregularities in the gas kinematics, we define three parameters: sigma_{PA} (standard deviation of the kinematic position angle), Delta phi (the average misalignment between kinematic and photometric position angles) and k_{3,5} (squared sum of the higher order Fourier terms). Using local, undistorted galaxies from SINGS, these can be used to establish the regularity of the gas velocity fields. Here we present the analysis of 22 distant galaxies in the MS0451.6-0305 field with 11 members at z=0.54. In this sample we find both field (4 out of 8) and cl...

  2. Evolutionary Status of Early-Type Galaxies in Distant Poor Clusters

    CERN Document Server

    Fritz, A

    2004-01-01

    We introduce our project that investigates the kinematic properties of early-type galaxies in 6 distant poor clusters at z~0.25. This study represents a continuation of our efforts to understand galaxy evolution in low-density environments. Higher-resolution MOSCA spectra have been obtained at the Calar Alto 3.5-m telescope with which we can measure absorption line strengths and velocity dispersions. In conjunction with our HST/F702W images of all the clusters, we are able to construct the Fundamental Plane of ellipticals and S0 galaxies in poor clusters at a look-back time of ~3 Gyrs. For galaxies outside the HST field, we concentrate our analysis on the Mg-sigma and Faber-Jackson relations. With the line strength diagrams age/metallicity distributions can be derived in densities between the field and rich cluster environments. Comparing with our rich clusters at the same cosmic epochs, the dependence of galaxy formation models on the local environment can be tested more quantitatively.

  3. The Distant Outer Gas Arm Between l=35d and l=45d

    CERN Document Server

    Su, Yang; Li, Chong; Zhang, Shaobo; Zhou, Xin; Fang, Min; Yang, Ji; Chen, Xuepeng

    2016-01-01

    The Galactic plane has been mapped from l=34.75d to 45.25d and b=-5.25d to 5.25d in the CO (J=1-0) emission with the 13.7 m telescope of the Purple Mountain Observatory. The unbiased survey covers a large area of 100 square degrees sampled every 30" with a velocity resolution of ~0.2km/s. In this paper, we present the result of an unbiased CO survey of this longitude and latitude range in the velocity range from -60km/s to -10km/s. Over 500 molecular clouds (MCs) are picked out from the 12CO emission, and 131 of these MCs are associated with 13CO emission.The distant MCs, which lie beyond the solar circle and are mostly concentrated in the Galactic plane, trace the large-scale molecular gas structure over 10 degrees of Galactic azimuth. We suggest that the CO emission of the segment is from the Outer Arm. The physical mid-plane traced by the Outer Arm seems to be slightly displaced from the IAU-defined plane on a large scale, which could be explained by the warped plane at large Galactocentric distances of >~...

  4. Noninvasive brain stimulation in neurorehabilitation: Local and distant effects for motor recovery

    Directory of Open Access Journals (Sweden)

    Sook-Lei eLiew

    2014-06-01

    Full Text Available Noninvasive brain stimulation (NIBS may enhance motor recovery after neurological injury through the causal induction of plasticity processes. Neurological injury, such as stroke, often results in serious long-term physical disabilities, and despite intensive therapy, a large majority of brain injury survivors fail to regain full motor function. Emerging research suggests that NIBS techniques, such as transcranial magnetic (TMS and direct current (tDCS stimulation, in association with customarily used neurorehabilitative treatments, may enhance motor recovery. This paper provides a general review on TMS and tDCS paradigms, the mechanisms by which they operate and the stimulation techniques used in neurorehabilitation, specifically stroke. TMS and tDCS influence regional neural activity underlying the stimulation location and also distant interconnected network activity throughout the brain. We discuss recent studies that document NIBS effects on global brain activity measured with various neuroimaging techniques, which help to characterize better strategies for more accurate NIBS stimulation. These rapidly growing areas of inquiry may hold potential for improving the effectiveness of NIBS-based interventions for clinical rehabilitation.

  5. Solar system constraints on planetary Coriolis-type effects induced by rotation of distant masses

    CERN Document Server

    Iorio, Lorenzo

    2010-01-01

    We phenomenologically put local constraints on the rotation of distant masses by using the planets of the solar system. First, we analytically compute the orbital secular precessions induced on the motion of a test particle about a massive primary by a Coriolis-like force, treated as a small perturbation, in the case of a constant angular velocity vector \\Psi directed along a generic direction in space. The semimajor axis a and the eccentricity e of the test particle do not secularly precess, contrary to the inclination I, the longitude of the ascending node \\Omega, the longitude of the pericenter \\varpi and the mean anomaly M. Then, we compare our prediction for with the corrections \\Delta\\dot\\varpi to the usual perihelion precessions of the inner planets recently estimated by fitting long data sets with different versions of the EPM ephemerides. We obtain |\\Psi_z| <= 0.0006-0.013 arcsec cty^-1, |\\Psi_x| <= 0.1-2.7 arcsec cty-1, |\\Psi_y| <= 0.3-2.3 arcsec cty^-1. Interpreted in terms of models of s...

  6. Bioinformatics analyses provide insight into distant homology of the Keap1-Nrf2 pathway.

    Science.gov (United States)

    Gacesa, Ranko; Dunlap, Walter C; Long, Paul F

    2015-11-01

    An essential requirement for the evolution of early eukaryotic life was the development of effective means to protect against metabolic oxidative stress and exposure to environmental toxicants. In present-day mammals, the master transcription factor Nrf2 regulates basal level homeostasis and inducible expression of numerous detoxifying and antioxidant genes. To examine early evolution of the Keap1-Nrf2 pathway, we present bioinformatics analyses of distant homology of mammalian Keap1 and Nrf2 proteins across the Kingdoms of Life. Software written for this analysis is made freely available on-line. Furthermore, utilizing protein modeling and virtual screening methods, we demonstrate potential for Nrf2 activation by competitive inhibition of its binding to Keap1, specifically by UV-protective fungal mycosporines and marine mycosporine-like amino acids (MAAs). We contend that coevolution of Nrf2-activating secondary metabolites by fungi and other extant microbiota may provide prospective compound leads for the design of new therapeutics to target activation of the human Keap1-Nrf2 pathway for treating degenerative diseases of ageing.

  7. Cedratvirus, a Double-Cork Structured Giant Virus, is a Distant Relative of Pithoviruses

    Science.gov (United States)

    Andreani, Julien; Aherfi, Sarah; Bou Khalil, Jacques Yaacoub; Di Pinto, Fabrizio; Bitam, Idir; Raoult, Didier; Colson, Philippe; La Scola, Bernard

    2016-01-01

    Most viruses are known for the ability to cause symptomatic diseases in humans and other animals. The discovery of Acanthamoeba polyphaga mimivirus and other giant amoebal viruses revealed a considerable and previously unknown area of uncharacterized viral particles. Giant viruses have been isolated from various environmental samples collected from very distant geographic places, revealing a ubiquitous distribution. Their morphological and genomic features are fundamental elements for classifying them. Herein, we report the isolation and draft genome of Cedratvirus, a new amoebal giant virus isolated in Acanthamoeba castellanii, from an Algerian environmental sample. The viral particles are ovoid-shaped, resembling Pithovirus sibericum, but differing notably in the presence of two corks at each extremity of the virion. The draft genome of Cedratvirus—589,068 base pairs in length—is a close relative of the two previously described pithoviruses, sharing 104 and 113 genes with P. sibericum and Pithovirus massiliensis genomes, respectively. Interestingly, analysis of these viruses’ core genome reveals that only 21% of Cedratvirus genes are involved in best reciprocal hits with the two pithoviruses. Phylogeny reconstructions and comparative genomics indicate that Cedratvirus is most closely related to pithoviruses, and questions their membership in an enlarged putative Pithoviridae family. PMID:27827884

  8. Cedratvirus, a Double-Cork Structured Giant Virus, is a Distant Relative of Pithoviruses

    Directory of Open Access Journals (Sweden)

    Julien Andreani

    2016-11-01

    Full Text Available Most viruses are known for the ability to cause symptomatic diseases in humans and other animals. The discovery of Acanthamoeba polyphaga mimivirus and other giant amoebal viruses revealed a considerable and previously unknown area of uncharacterized viral particles. Giant viruses have been isolated from various environmental samples collected from very distant geographic places, revealing a ubiquitous distribution. Their morphological and genomic features are fundamental elements for classifying them. Herein, we report the isolation and draft genome of Cedratvirus, a new amoebal giant virus isolated in Acanthamoeba castellanii, from an Algerian environmental sample. The viral particles are ovoid-shaped, resembling Pithovirus sibericum, but differing notably in the presence of two corks at each extremity of the virion. The draft genome of Cedratvirus—589,068 base pairs in length—is a close relative of the two previously described pithoviruses, sharing 104 and 113 genes with P. sibericum and Pithovirus massiliensis genomes, respectively. Interestingly, analysis of these viruses’ core genome reveals that only 21% of Cedratvirus genes are involved in best reciprocal hits with the two pithoviruses. Phylogeny reconstructions and comparative genomics indicate that Cedratvirus is most closely related to pithoviruses, and questions their membership in an enlarged putative Pithoviridae family.

  9. Gall bladder carcinoma: Aggressive malignancy with protean loco-regional and distant spread.

    Science.gov (United States)

    Dwivedi, Amit Nandan Dhar; Jain, Shivi; Dixit, Ruhi

    2015-03-16

    The most common malignancy of biliary tract is gallbladder cancer (GBC) which is the third most common cancer in gastrointestinal tract. It is a lethal disease for most patients in spite of growing awareness and improved diagnostic techniques. GBC has a very poor prognosis and the 5 year survival rate is loco-regional rather than distant. It spreads by lymphatic, vascular, neural, intraperitoneal, and intraductal routes. Sonography is usually the most common imaging test to evaluate symptoms of biliary tract disease including suspected GC. With recent advances in imaging modalities like multi-detector computed tomography (CT) scanners, magnetic resonance imaging-positron emission tomography/CT diagnosis of gallbladder cancer has improved. Studies have also targeted molecular and genetic pathways. Treatment options have included extended and radical surgeries and adjuvant chemotherapy. This review article deals in detail with important aspects of carcinoma gallbladder and its manifestations and challenges. Role of various imaging modalities in characterization and accurate staging has been discussed. The loco-regional spread of this aggressive malignancy is dealt explicitly.

  10. A distant coilin homologue is required for the formation of cajal bodies in Arabidopsis.

    Science.gov (United States)

    Collier, Sarah; Pendle, Alison; Boudonck, Kurt; van Rij, Tjeerd; Dolan, Liam; Shaw, Peter

    2006-07-01

    Cajal bodies (CBs) are subnuclear bodies that are widespread in eukaryotes, being found in mammals, many other vertebrates and in all plant species so far examined. They are mobile structures, moving, fusing, and budding within the nucleus. Here we describe a screen for Arabidopsis mutants with altered CBs and describe mutants that have smaller Cajal bodies (ncb-2, ncb-3), lack them altogether (ncb-1), have increased numbers of CBs (pcb) or have flattened CBs (ccb). We have identified the gene affected in the ncb mutants as a distant homolog of the vertebrate gene that encodes coilin (At1g13030) and have termed the resulting protein Atcoilin. A T-DNA insertional mutant in this gene (ncb-4) also lacks Cajal bodies. Overexpression of Atcoilin cDNA in ncb-1 restores Cajal bodies, which recruit U2B'' as in the wild type, but which are, however, much larger than in the wild type. Thus we have shown that At1g13030 is required for Cajal body formation in Arabidopsis, and we hypothesize that the level of its expression is correlated with Cajal body size. The Atcoilin gene is unaffected in pcb and ccb, suggesting that other genes can also affect CBs.

  11. Mercury and its bioconcentration factors in fly agaric (Amanita muscaria) from spatially distant sites in Poland.

    Science.gov (United States)

    Falandysz, J; Lipka, K; Mazur, A

    2007-09-01

    Total mercury content has been determined in the fruiting bodies of fly agaric (Amanita muscaria) and topsoil layer (0-10 cm) collected from 14 spatially distant sites across Poland. Mercury was measured by cold-vapor atomic absorption spectroscopy (CV-AAS) after nitric acid (mushrooms) or nitric acid and sulfuric acid (soil) digestion of the samples. The caps, depending on the site, contained total mercury at mean concentrations from 0.24+/-0.13 to 1.4+/-0.6 microg/g dm (median 0.19-1.4 microg/g dm), and stalks from 0.18+/-0.06 to 0.71+/-0.26 microg/g dm (median 0.18-0.67 microg/g dm). An overall-mean the total mercury content for 204 caps and stalks was, respectively, 0.73+/-0.55 (0.05-3.3 microg/g dm) and 0.43+/-0.33 (0.09-2.3 microg/g dm).

  12. Discovery of VHE gamma-rays from the distant BL Lac 1ES 0347-121

    CERN Document Server

    Aharonian, F; Barres de Almeida, U; Bazer-Bachi, A R; Behera, B; Beilicke, M; Benbow, W; Bernlöhr, K; Boisson, C; Bolz, O; Borrel, V; Braun, I; Brion, E; Brown, A M; Buhler, R; Bulik, T; Büsching, I; Boutelier, T; Carrigan, S; Chadwick, P M; Chounet, L M; Clapson, A C; Coignet, G; Cornils, R; Costamante, L; Dalton, M; Degrange, B; Dickinson, H J; Djannati-Ata:, A; Domainko, W; O'Connor-Drury, L; Dubois, F; Dubus, G; Dyks, J; Egberts, K; Emmanoulopoulos, D; Espigat, P; Farnier, C; Feinstein, F; Fiasson, A; Förster, A; Fontaine, G; Funk, Seb; Fuling, M; Gallant, Y A; Giebels, B; Glicenstein, J F; Glück, B; Goret, P; Hadjichristidis, C; Hauser, D; Hauser, M; Heinzelmann, G; Henri, G; Hermann, G; Hinton, J A; Hoffmann, A; Hofmann, W; Holleran, M; Hoppe, S; Horns, D; Jacholkowska, A; De Jager, O C; Jung, I; Katarzynski, K; Kendziorra, E; Kerschhaggl, M; Khelifi, B; Keogh, D; Komin, Nu; Kosack, K; Lamanna, G; Latham, I J; Lemiere, A; Lemoine-Goumard, M; Lenain, J P; Lohse, T; Martin, J M; Martineau-Huynh, O; Marcowith, A; Masterson, C; Maurin, D; Maurin, G; McComb, T J L; Moderski, R; Moulin, E; De Naurois, Mathieu; Nedbal, D; Nolan, S J; Ohm, S; Olive, J P; De Ona Wilhelmi, E; Orford, K J; Osborne, J L; Ostrowski, M; Panter, M; Pedaletti, G; Pelletier, G; Petrucci, P O; Pita, S; Pühlhofer, G; Punch, M; Ranchon, S; Raubenheimer, B C; Raue, M; Rayner, S M; Renaud, M; Ripken, J; Rob, L; Rolland, L; Rosier-Lees, S; Rowell, G; Rudak, B; Ruppel, J; Sahakian, V V; Santangelo, A; Schlickeiser, R; Schock, F; Schroder, R; Schwanke, U; Schwarzburg, S; Schwemmer, S; Shalchi, A; Sol, H; Spangler, D; Stawarz,; Steenkamp, R; Stegmann, C; Superina, G; Tam, P H; Tavernet, J P; Terrier, R; Van Eldik, C; Vasileiadis, G; Venter, C; Vialle, J P; Vincent, P; Vivier, M; Völk, H J; Volpe, F; Wagner, S J; Ward, M; Zdziarski, A A; Zech, A

    2007-01-01

    Aims: Our aim is to study the production mechanism for very-high-energy (VHE; >100GeV) gamma-rays in distant active galactic nuclei (AGN) and use the observed VHE spectrum to derive limits on the Extragalactic Background Light (EBL). We also want to determine physical quantities through the modeling of the object's broad-band spectral energy distribution (SED). Methods: VHE observations (~25h live time) of the BL Lac 1ES 0347-121 (redshift z=0.188) were conducted with the High Energy Stereoscopic System (H.E.S.S.) between August and December 2006. Contemporaneous X-ray and UV/optical observations from the SWIFT satellite are used to interpret the SED of the source in terms of a synchrotron self Compton (SSC) model. Results: An excess of 327 events, corresponding to a statistical significance of 10.1 standard deviations, is detected from 1ES 0347-121. Its photon spectrum, ranging from ~250GeV to ~3TeV, is well described by a power law with a photon index of Gamma = 3.10 +/- 0.23_stat +/- 0.10_sys. The integral...

  13. Effect of clarythromycin on the distant metastases of human lung cancer cells in SCID mice.

    Science.gov (United States)

    Parajuli, P; Yano, S; Hanibuchi, M; Nokihara, H; Shinohara, T; Sone, S

    1998-02-01

    Recently, the use of macrolides is suggested to be therapeutically effective in prolonging the survival of patients with inoperable non-small cell lung cancer. The purpose of this study was to examine therapeutic effects of a macrolide, clarythromycin (CAM) on the metastastic developments of two different human non-small cell lung cancers (squamous cell lung carcinoma RERF-LC-AI, and adenocarcinoma PC-14) in severe combined immunodeficient (SCID) mice depleted or undepleted of natural killer (NK) cells, respectively. CAM, injected subcutaneously at doses of 5 and 10 mg/kg body weight/day from day 7 to 41 after i.v. inoculation of human lung cancer cells, was not effective in inhibiting their distant organ metastases in SCID mice. CAM at concentrations of less than 10 micrograms/ml did not have a direct influence on the proliferation of these tumor cells in vitro. Although CAM alone was not effective in augmenting NK activity, it augmented the IL-2-induced killer (LAK) activity against Daudi cells in vitro. These results suggest that CAM alone may not be enough to control the spread of non-small cell lung cancer in the patient with T cell dysfunction.

  14. Multiple-angle 3D video technology for distant live concerts

    Science.gov (United States)

    Inoue, Tetsuri; Komiya, Kazumi; Momose, Keiko; Urano, Yoshiyori; Tominaga, Hideyoshi

    2002-03-01

    We are developing a multiple-angle 3D-video system that will allow an audience to enjoy a concert in real time at a distant location by simultaneously shooting multiple stereoscopic images from different angles and transmitting them through a high-speed network. At the receiving side, a decoder restores the original image signals from the received data, and different video images are shown on multiple stereoscopic displays. As a result, the audience can enjoy multiple images of a concert at the same time. The purpose of this system is to give a remote audience the opportunity to enjoy a live concert as though they were at the concert site. This paper examines the technical requirements for the camera arrangement and the transmission rate needed to transmit images of a musical performance with this system. We have built an experimental system with four stereo cameras, and have experimentally transmitted musical performance images to test the system performance. In this paper, we also propose a method for transmitting multiple camera images more efficiently.

  15. A close-pair binary in a distant triple supermassive black-hole system

    CERN Document Server

    Deane, R P; Jarvis, M J; Coriat, M; Bernardi, G; Fender, R P; Frey, S; Heywood, I; Klöckner, H -R; Grainge, K; Rumsey, C

    2014-01-01

    Galaxies are believed to evolve through merging, which should lead to multiple supermassive black holes in some. There are four known triple black hole systems, with the closest pair being 2.4 kiloparsecs apart (the third component is more distant at 3 kiloparsecs), which is far from the gravitational sphere of influence of a black hole with mass $\\sim$10$^9$ M$_\\odot$ (about 100 parsecs). Previous searches for compact black hole systems concluded that they were rare, with the tightest binary system having a separation of 7 parsecs. Here we report observations of a triple black hole system at redshift z=0.39, with the closest pair separated by $\\sim$140 parsecs. The presence of the tight pair is imprinted onto the properties of the large-scale radio jets, as a rotationally-symmetric helical modulation, which provides a useful way to search for other tight pairs without needing extremely high resolution observations. As we found this tight pair after searching only six galaxies, we conclude that tight pairs ar...

  16. Ultrastructure of the spermatozoa of Psammotettix striatus (Linnaeus) and Exitianus nanus (Distant) (Hemiptera: Auchenorrhyncha: Cicadellidae: Deltocephalinae).

    Science.gov (United States)

    Su, Mei; Dietrich, Christopher H; Zhang, Yalin; Dai, Wu

    2014-11-01

    Previous studies of insect spermatozoa indicate that these specialized cells have undergone significant morphological evolution and exhibit traits useful for reconstructing phylogenetic relationships. Although leafhoppers (Cicadellidae) are among the largest and most economically important insect families, few comparative studies of their spermatozoa have been published. Here, the ultrastructure of mature spermatozoa of two leafhoppers Psammotettix striatus (Linnaeus) and Exitianus nanus (Distant), representing two different tribes of the largest leafhopper subfamily, Deltocephalinae, was examined by light and transmission electron microscopy. The shape and ultrastructure of spermatozoa of the two species are very similar to those of other Cicadellidae as well as other Auchenorrhyncha, comprising a conical acrosome invaginated to form a subacrosomal space, a filiform homogeneously condensed nucleus, a lamellate centriolar adjunct connecting the nucleus with the mid-piece/flagellum, a long flagellum with a 9 + 9 + 2 axoneme pattern and two symmetrical mitochondrial derivatives with an orderly array of peripheral cristae, and two drop-shaped accessory bodies. They may be distinguished by the size of the sperm, and the shape of the nucleus, accessory bodies, and paracrystalline region of mitochondrial derivatives. The fine morphology and ultrastructure of spermatozoon in P. striatus and E. nanus are illustrated, along with a brief discussion of the implications for classification and phylogenetic analyses of the subfamily.

  17. An isoprenylation and palmitoylation motif promotes intraluminal vesicle delivery of proteins in cells from distant species.

    Science.gov (United States)

    Oeste, Clara L; Pinar, Mario; Schink, Kay O; Martínez-Turrión, Javier; Stenmark, Harald; Peñalva, Miguel A; Pérez-Sala, Dolores

    2014-01-01

    The C-terminal ends of small GTPases contain hypervariable sequences which may be posttranslationally modified by defined lipid moieties. The diverse structural motifs generated direct proteins towards specific cellular membranes or organelles. However, knowledge on the factors that determine these selective associations is limited. Here we show, using advanced microscopy, that the isoprenylation and palmitoylation motif of human RhoB (-CINCCKVL) targets chimeric proteins to intraluminal vesicles of endolysosomes in human cells, displaying preferential co-localization with components of the late endocytic pathway. Moreover, this distribution is conserved in distant species, including cells from amphibians, insects and fungi. Blocking lipidic modifications results in accumulation of CINCCKVL chimeras in the cytosol, from where they can reach endolysosomes upon release of this block. Remarkably, CINCCKVL constructs are sorted to intraluminal vesicles in a cholesterol-dependent process. In the lower species, neither the C-terminal sequence of RhoB, nor the endosomal distribution of its homologs are conserved; in spite of this, CINCCKVL constructs also reach endolysosomes in Xenopus laevis and insect cells. Strikingly, this behavior is prominent in the filamentous ascomycete fungus Aspergillus nidulans, in which GFP-CINCCKVL is sorted into endosomes and vacuoles in a lipidation-dependent manner and allows monitoring endosomal movement in live fungi. In summary, the isoprenylated and palmitoylated CINCCKVL sequence constitutes a specific structure which delineates an endolysosomal sorting strategy operative in phylogenetically diverse organisms.

  18. A Statistical Study of Distant Consequences of Large Solar Energetic Events

    CERN Document Server

    Schrijver, Carolus J

    2015-01-01

    Large solar flares and eruptions may influence remote regions through perturbations in the outer-atmospheric magnetic field, leading to causally related events outside of the primary or triggering eruptions that are referred to as "sympathetic events." We quantify the occurrence of sympathetic events using the full-disk observations by the Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory associated with all flares of GOES class M5 or larger from 01 May 2010 through 31 December 2014. Using a superposed-epoch analysis, we find an increase in the rate of flares, filament eruptions, and substantial sprays and surges more than 20 degrees away from the primary flares within the first four hours at a significance of 1.8 standard deviations. We also find that the rate of distant events drops by two standard deviations, or a factor of 1.2, when comparing intervals between 4 hours and 24 hours before and after the start times of the primary large flares. We discuss the evidence for the concluding hyp...

  19. A Distant Echo of Milky Way Central Activity closes the Galaxy's Baryon Census

    CERN Document Server

    Nicastro, F; Krongold, Y; Mathur, S; Elvis, M

    2016-01-01

    We report on the presence of large amounts of million-degree gas in the Milky Way's interstellar and circum-galactic medium. This gas (1) permeates both the Galactic plane and the halo, (2) extends to distances larger than 60-200 kpc from the center, and (3) its mass is sufficient to close the Galaxy's baryon census. Moreover, we show that a vast, $\\sim 6$ kpc radius, spherically-symmetric central region of the Milky Way above and below the 0.16 kpc thick plane, has either been emptied of hot gas or the density of this gas within the cavity has a peculiar profile, increasing from the center up to a radius of $\\sim 6$ kpc, and then decreasing with a typical halo density profile. This, and several other converging pieces of evidence, suggest that the current surface of the cavity, at 6 kpc from the Galaxy's center, traces the distant echo of a period of strong nuclear activity of our super-massive black-hole, occurred about 6 Myrs ago.

  20. Evidence of unique and generalist microbes in distantly related sympatric intertidal marine sponges (Porifera: Demospongiae).

    Science.gov (United States)

    Alex, Anoop; Silva, Vitor; Vasconcelos, Vitor; Antunes, Agostinho

    2013-01-01

    The diversity and specificity of microbial communities in marine environments is a key aspect of the ecology and evolution of both the eukaryotic hosts and their associated prokaryotes. Marine sponges harbor phylogenetically diverse and complex microbial lineages. Here, we investigated the sponge bacterial community and distribution patterns of microbes in three sympatric intertidal marine demosponges, Hymeniacidon perlevis, Ophlitaspongia papilla and Polymastia penicillus, from the Atlantic coast of Portugal using classical isolation techniques and 16S rRNA gene clone libraries. Microbial composition assessment, with nearly full-length 16S rRNA gene sequences (ca. 1400 bp) from the isolates (n = 31) and partial sequences (ca. 280 bp) from clone libraries (n = 349), revealed diverse bacterial communities and other sponge-associated microbes. The majority of the bacterial isolates were members of the order Vibrionales and other symbiotic bacteria like Pseudovibrio ascidiaceiocola, Roseobacter sp., Hahellaceae sp. and Cobetia sp. Extended analyses using ecological metrics comprising 142 OTUs supported the clear differentiation of bacterial community profiles among the sponge hosts and their ambient seawater. Phylogenetic analyses were insightful in defining clades representing shared bacterial communities, particularly between H. perlevis and the geographically distantly-related H. heliophila, but also among other sponges. Furthermore, we also observed three distinct and unique bacterial groups, Betaproteobactria (~81%), Spirochaetes (~7%) and Chloroflexi (~3%), which are strictly maintained in low-microbial-abundance host species O. papilla and P. penicillus. Our study revealed the largely generalist nature of microbial associations among these co-occurring intertidal marine sponges.