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Sample records for jrvi magnus kallas

  1. Site investigation for Magnus

    SciTech Connect

    Semple, R.M.; Rigden, W.J.

    1983-05-01

    In April 1982, BP's Magnus structure was installed about 150 km northeast of the Shetland Islands. The most northerly, deepest water platform in the North Sea, the steel tower is supported on groups of 2 m diameter piles that were driven, in good accordance with predictions, to an average penetration of 85 m in strong cohesive soils. The paper describes investigations performed at the platform site, and documents soil characteristics for conventional and state of the art pile analyses. Reference is made to several innovative techniques first used at the Magnus site that have since been incorporated into the larger North Sea investigations. Information is given about the geological history of the site. Test results are presented on soil strength and stiffness, including critical state soil mechanics parameters, on residual pore pressures after sampling, and on the effect of sample size on strength characteristics.

  2. Rotary and Magnus balances

    NASA Technical Reports Server (NTRS)

    Malcolm, G. N.

    1981-01-01

    Two wind tunnel techniques for determining part of the aerodynamic information required to describe the dynamic bahavior of various types of vehicles in flight are described. Force and moment measurements are determined with a rotary-balance apparatus in a coning motion and with a Magnus balance in a high-speed spinning motion. Coning motion is pertinent to both aircraft and missiles, and spinning is important for spin stabilized missiles. Basic principles of both techniques are described, and specific examples of each type of apparatus are presented. Typical experimental results are also discussed.

  3. Magnus effect power generator

    SciTech Connect

    Borg, J.L.; Borg, C.J.

    1984-05-01

    Magnus cylinders are mounted for rotation at right angles to shafts that are revolved about a generally vertical axis. The shafts are free to rotate 180/sup 0/. The Magnus cylinders are continuously rotated in the same angular direction. At one position of revolution of the shafts, the cylinders rotate on an axis generally parallel to the axis of revolution of the shafts. When the apparatus is immersed in a fluid flow (gaseous or liquid) a torque of rotation is developed when the shafts are aligned with the fluid flow, and this torque of rotation is reduced as the shaft approaches a position transverse to the fluid flow. As the shafts pass this transverse position, a torque is developed by the rotating cylinder that rotates the shafts 180/sup 0/ until the formerly downwardly depending cylinder is now upright and the formerly upright cylinder is now downwardly depending on its shaft. With two or more shafts to which cylinders are attached, there is a continuous production of torque about the axis of revolution of the shafts.

  4. Magnus air turbine system

    DOEpatents

    Hanson, Thomas F.

    1982-01-01

    A Magnus effect windmill for generating electrical power is disclosed. A large nacelle-hub mounted pivotally (in Azimuth) atop a support tower carries, in the example disclosed, three elongated barrels arranged in a vertical plane and extending symmetrically radially outwardly from the nacelle. The system provides spin energy to the barrels by internal mechanical coupling in the proper sense to cause, in reaction to an incident wind, a rotational torque of a predetermined sense on the hub. The rotating hub carries a set of power take-off rollers which ride on a stationary circular track in the nacelle. Shafts carry the power, given to the rollers by the wind driven hub, to a central collector or accumulator gear assembly whose output is divided to drive the spin mechanism for the Magnus barrels and the main electric generator. A planetary gear assembly is interposed between the collector gears and the spin mechanism functioning as a differential which is also connected to an auxiliary electric motor whereby power to the spin mechanism may selectively be provided by the motor. Generally, the motor provides initial spin to the barrels for start-up after which the motor is braked and the spin mechanism is driven as though by a fixed ratio coupling from the rotor hub. During high wind or other unusual conditions, the auxiliary motor may be unbraked and excess spin power may be used to operate the motor as a generator of additional electrical output. Interposed between the collector gears of the rotating hub and the main electric generator is a novel variable speed drive-fly wheel system which is driven by the variable speed of the wind driven rotor and which, in turn, drives the main electric generator at constant angular speed. Reference is made to the complete specification for disclosure of other novel aspects of the system such as, for example, the aerodynamic and structural aspects of the novel Magnus barrels as well as novel gearing and other power coupling

  5. A note on Magnus formula

    NASA Astrophysics Data System (ADS)

    Prato, D.; Lamberti, P. W.

    1997-03-01

    In this paper we reanalyze the Magnus formula for the time evolution operator in quantum mechanics from an algorithmic point of view. We give some rules to obtain the general term in the expansion as a compact time-ordered integral. These rules are easily applied to higher orders; in particular, we give explicitly the fifth order.

  6. Magnus effects on spinning transonic missiles

    NASA Technical Reports Server (NTRS)

    Seginer, A.; Rosenwasser, I.

    1983-01-01

    Magnus forces and moments were measured on a basic-finner model spinning in transonic flow. Spin was induced by canted fins or by full-span or semi-span, outboard and inboard roll controls. Magnus force and moment reversals were caused by Mach number, reduced spin rate, and angle of attack variations. Magnus center of pressure was found to be independent of the angle of attack but varied with the Mach number and model configuration or reduced spin rate.

  7. STS-112 Crew Interviews - Magnus

    NASA Technical Reports Server (NTRS)

    2002-01-01

    STS-112 Mission Specialist 2 Sandra H. Magnus is seen during a prelaunch interview. She answers questions about her inspiration to become an astronaut and her career path. She gives details on the mission's goals, the most significant of which will be the installation of the S-1 truss structure on the International Space Station (ISS). The installation, one in a series of truss extending missions, will be complicated and will require the use of the robotic arm as well as extravehicular activity (EVA) by astronauts. Magnus also describes her function in the performance of transfer operations. Brief descriptions are given of experiments on board the ISS as well as on board the Shuttle.

  8. [Handwritten documents of 'Antidotarius magnus'].

    PubMed

    Kramer, A; Scheidt, K

    1999-01-01

    The 'Antidotarius magnus'--compiled about 1080 by the archbishop of Salerno, Alphanus--deals with the pharmacological methods of healing and contains nearly 1073 antidots. We have discovered 13 Latin manuscripts of the 'Antidotarius magnus' in the libraries of Basel, Bern, Cambridge, Erfurt, Florence, London, Oxford, Paris and Parma. One should remember that the MS Taurin.I.VI.24 had been totally destroyed in 1904, but this manuscript is still noted in the catalogues of Pasin, Giacosa and Thorndike/Kibre. The most remarkable manuscript--the MS Palat.lat.747--is preserved in the National Library at Florence. The MS Palat.lat.747 is dated to 1153 and seems to be similar to the archetype. We are currently preparing a critical edition based on the oldest manuscripts.

  9. Magnus approximation in neutrino oscillations

    NASA Astrophysics Data System (ADS)

    Acero, Mario A.; Aguilar-Arevalo, Alexis A.; D'Olivo, J. C.

    2011-04-01

    Oscillations between active and sterile neutrinos remain as an open possibility to explain some anomalous experimental observations. In a four-neutrino (three active plus one sterile) mixing scheme, we use the Magnus expansion of the evolution operator to study the evolution of neutrino flavor amplitudes within the Earth. We apply this formalism to calculate the transition probabilities from active to sterile neutrinos with energies of the order of a few GeV, taking into account the matter effect for a varying terrestrial density.

  10. Magnus force effect in optical manipulation

    NASA Astrophysics Data System (ADS)

    Cipparrone, Gabriella; Hernandez, Raul Josue; Pagliusi, Pasquale; Provenzano, Clementina

    2011-07-01

    The effect of the Magnus force in optical micromanipulation has been observed. An ad hoc experiment has been designed based on a one-dimensional optical trap that carries angular momentum. The observed particle dynamics reveals the occurrence of this hydrodynamic force, which is neglected in the common approach. Its measured value is larger than the one predicted by the existing theoretical models for micrometric particles and low Reynolds number, showing that the Magnus force can contribute to unconventional optohydrodynamic trapping and manipulation.

  11. Magnus force effect in optical manipulation

    SciTech Connect

    Cipparrone, Gabriella; Pagliusi, Pasquale; Hernandez, Raul Josue; Provenzano, Clementina

    2011-07-15

    The effect of the Magnus force in optical micromanipulation has been observed. An ad hoc experiment has been designed based on a one-dimensional optical trap that carries angular momentum. The observed particle dynamics reveals the occurrence of this hydrodynamic force, which is neglected in the common approach. Its measured value is larger than the one predicted by the existing theoretical models for micrometric particles and low Reynolds number, showing that the Magnus force can contribute to unconventional optohydrodynamic trapping and manipulation.

  12. General Education at Albertus Magnus College.

    ERIC Educational Resources Information Center

    Savage, Mary

    An alternative general education program for freshmen at Albertus Magnus College is described. The program, an interdisciplinary student-centered introduction to general education, is composed of two parts that the student takes concurrently: (1) a year-long seminar in thought and expression, and (2) a sequence of four (usually 7-week) courses in…

  13. Internal Magnus effects in superfluid 3A

    NASA Astrophysics Data System (ADS)

    Salmelin, R. H.; Salomaa, M. M.; Mineev, V. P.

    1989-08-01

    Orbital angular momentum of the coherently aligned Cooper pairs in superfluid 3A is encountered by an object immersed in the condensate. We evaluate the associated quasiparticle-scattering asymmetry experienced by a negative ion; this leads to a measureable, purely quantum-mechanical reactive force deflecting the ion's trajectory. Possible hydrodynamic Magnus effects are also discussed.

  14. A Pedagogical Approach to the Magnus Expansion

    ERIC Educational Resources Information Center

    Blanes, S.; Casas, F.; Oteo, J. A.; Ros, J.

    2010-01-01

    Time-dependent perturbation theory as a tool to compute approximate solutions of the Schrodinger equation does not preserve unitarity. Here we present, in a simple way, how the "Magnus expansion" (also known as "exponential perturbation theory") provides such unitary approximate solutions. The purpose is to illustrate the importance and…

  15. CFD Prediction of Magnus Effect in Subsonic to Supersonic Flight

    DTIC Science & Technology

    2009-09-01

    CFD Prediction of Magnus Effect in Subsonic to Supersonic Flight by James DeSpirito ARL-TR-4929 September 2009...of Magnus Effect in Subsonic to Supersonic Flight James DeSpirito Weapons and Materials Research Directorate, ARL...TITLE AND SUBTITLE CFD Prediction of Magnus Effect in Subsonic to Supersonic Flight 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT

  16. New twist to steering. [Magnus effect rotors

    SciTech Connect

    Borg, J.L.

    1980-06-01

    The new vessel steering system is based on The Magnus Effect which is defined in simplified terms; if a vertical cylinder immersed in water is rotated, it produces a force at right angles to the direction of the water flowing past it. The Magnus Effect rotor needs only sufficient torque to overcome bearing and surface friction forces, so that the power requirements are very low. Further energy savings are realized because the rotor can develop maximum turning force or can return to zero in a few seconds. Tests with these cylindrical rudders have been conducted to verify the hydrodynamic theory. This concept is in the preliminary stages of development. Results are expected soon from field testing on an 1800-hp pushboat working four barges on the Warrior and Tombigbee Rivers in Alabama and Mississippi.

  17. Magnus force in superfluids and superconductors

    NASA Astrophysics Data System (ADS)

    Sonin, E. B.

    1997-01-01

    The forces on the vortex, transverse to its velocity, are considered. In addition to the superfluid Magnus force from the condensate (superfluid component), there are transverse forces from thermal quasiparticles and external fields violating the Galilean invariance. The forces between quasiparticles and the vortex originate from interference of quasiparticles with trajectories on the left and on the right from the vortex like similar forces for electrons interacting with the thin magnetic-flux tube (the Aharonov-Bohm effect). These forces are derived for phonons from the equations of superfluid hydrodynamics, and for BCS quasiparticles from the Bogolyubov-de Gennes equations. The effect of external fields breaking Galilean invariance is analyzed for vortices in the two-dimensional Josephson junction array. The symmetry analysis of the classical equations for the array shows that the total transverse force on the vortex vanishes. Therefore the Hall effect which is linear in the transverse force is absent also. This means that the Magnus force from the superfluid component exactly cancels with the transverse force from the external fields. The results of other approaches are also brought together for discussion.

  18. Inverse Magnus effect on a rotating sphere

    NASA Astrophysics Data System (ADS)

    Kim, Jooha; Park, Hyungmin; Choi, Haecheon; Yoo, Jung Yul

    2011-11-01

    In this study, we investigate the flow characteristics of rotating spheres in the subcritical Reynolds number (Re) regime by measuring the drag and lift forces on the sphere and the two-dimensional velocity in the wake. The experiment is conducted in a wind tunnel at Re = 0 . 6 ×105 - 2 . 6 ×105 and the spin ratio (ratio of surface velocity to the free-stream velocity) of 0 (no spin) - 0.5. The drag coefficient on a stationary sphere remains nearly constant at around 0.52. However, the magnitude of lift coefficient is nearly zero at Re < 2 . 0 ×105 , but rapidly increases to 0.3 and then remains constant with further increasing Reynolds number. On the other hand, with rotation, the lift coefficient shows negative values, called inverse Magnus effect, depending on the magnitudes of the Reynolds number and spin ratio. The velocity field measured from a particle image velocimetry (PIV) indicates that non-zero lift coefficient on a stationary sphere at Re > 2 . 0 ×105 results from the asymmetry of separation line, whereas the inverse Magnus effect for the rotating sphere results from the differences in the boundary-layer growth and separation along the upper and lower sphere surfaces. Supported by the WCU, Converging Research Center and Priority Research Centers Program, NRF, MEST, Korea.

  19. Magnus force in superfluids and superconductors

    SciTech Connect

    Sonin, E.B. |

    1997-01-01

    The forces on the vortex, transverse to its velocity, are considered. In addition to the superfluid Magnus force from the condensate (superfluid component), there are transverse forces from thermal quasiparticles and external fields violating the Galilean invariance. The forces between quasiparticles and the vortex originate from interference of quasiparticles with trajectories on the left and on the right from the vortex like similar forces for electrons interacting with the thin magnetic-flux tube (the Aharonov-Bohm effect). These forces are derived for phonons from the equations of superfluid hydrodynamics, and for BCS quasiparticles from the Bogolyubov{endash}de Gennes equations. The effect of external fields breaking Galilean invariance is analyzed for vortices in the two-dimensional Josephson junction array. The symmetry analysis of the classical equations for the array shows that the total transverse force on the vortex vanishes. Therefore the Hall effect which is linear in the transverse force is absent also. This means that the Magnus force from the superfluid component {ital exactly} cancels with the transverse force from the external fields. The results of other approaches are also brought together for discussion. {copyright} {ital 1997} {ital The American Physical Society}

  20. Magnus Forces and Statistics in 2 + 1 Dimensions

    NASA Astrophysics Data System (ADS)

    Davis, R. L.

    Spinning vortex solutions to the abelian Higgs model, not Nielsen-Olesen solutions, are appropriate to a Ginzburg-Landau description of superconductivity. The main physical distinction is that spinning vortices experience the Magnus force while Nielsen-Olesen vortices do not. In 2 + 1 dimensional superconductivity without a Chern-Simons interaction, the effect of the Magnus force is equivalent to that of a background fictitious magnetic field. Moreover, the phase obtained an interchanging two quasi-particles is always path-dependent. When a Chern-Simons term is added there is an additional localized Magnus flux at the vortex. For point-like vortices, the Chern-Simons interaction can be seen as defining their intrinsic statistics, but in realistic cases of vortices with finite size in strong Magnus fields the quasi-particle statistics are not well-defined.

  1. Magnus Effect on a Spinning Satellite in Low Earth Orbit

    NASA Technical Reports Server (NTRS)

    Ramjatan, Sahadeo; Fitz-Coy, Norman; Yew, Alvin Garwai

    2016-01-01

    A spinning body in a flow field generates an aerodynamic lift or Magnus effect that displaces the body in a direction normal to the freestream flow. Earth orbiting satellites with substantial body rotation in appreciable atmospheric densities may generate a Magnus force to perturb orbital dynamics. We investigate the feasibility of using this effect for spacecraft at a perigee of 80km using the Systems Tool Kit (STK). Results show that for a satellite of reasonable properties, the Magnus effect doubles the amount of time in orbit. Orbital decay was greatly mitigated for satellites spinning at 10000 and 15000RPM. This study demonstrates that the Magnus effect has the potential to sustain a spacecraft's orbit at a low perigee altitude and could also serve as an orbital maneuver capability.

  2. Magnus forces and statistics in 2 + 1 dimensions

    SciTech Connect

    Davis, R.L. )

    1990-05-10

    Spinning vortex solutions to the abelian Higgs model, not Nielsen-Olesen solutions, are appropriate to a Ginzburg-Landau description of superconductivity. The main physical distinction is that spinning vortices experience the Magnus force while Nielsen-Olesen vortices do not. In 2 + 1 dimensional superconductivity without a Chern-Simons interaction, the effect of the Magnus force is equivalent to that of a background fictitious magnetic field. Moreover, the phase obtained an interchanging two quasi-particles is always path-dependent. When a Chern-Simons term is added there is an additional localized Magnus flux at the vortex. For point-like vortices, the Chern-Simons interaction can be seen as defining their intrinsic statistics, but in realistic cases of vortices with finite size in strong Magnus fields the quasi-particle statistics are not well-defined.

  3. Unravelling the structure of Magnus' pink salt.

    PubMed

    Lucier, Bryan E G; Johnston, Karen E; Xu, Wenqian; Hanson, Jonathan C; Senanayake, Sanjaya D; Yao, Siyu; Bourassa, Megan W; Srebro, Monika; Autschbach, Jochen; Schurko, Robert W

    2014-01-29

    A combination of multinuclear ultra-wideline solid-state NMR, powder X-ray diffraction (pXRD), X-ray absorption fine structure experiments, and first principles calculations of platinum magnetic shielding tensors has been employed to reveal the previously unknown crystal structure of Magnus' pink salt (MPS), [Pt(NH3)4][PtCl4], study the isomeric Magnus' green salt (MGS), [Pt(NH3)4][PtCl4], and examine their synthetic precursors K2PtCl4 and Pt(NH3)4Cl2·H2O. A simple synthesis of MPS is detailed which produces relatively pure product in good yield. Broad (195)Pt, (14)N, and (35)Cl SSNMR powder patterns have been acquired using the WURST-CPMG and BRAIN-CP/WURST-CPMG pulse sequences. Experimentally measured and theoretically calculated platinum magnetic shielding tensors are shown to be very sensitive to the types and arrangements of coordinating ligands as well as intermolecular Pt-Pt metallophilic interactions. High-resolution (195)Pt NMR spectra of select regions of the broad (195)Pt powder patterns, in conjunction with an array of (14)N and (35)Cl spectra, reveal clear structural differences between all compounds. Rietveld refinements of synchrotron pXRD patterns, guided by first principles geometry optimization calculations, yield the space group, unit cell parameters, and atomic positions of MPS. The crystal structure has P-1 symmetry and resides in a pseudotetragonal unit cell with a distance of >5.5 Å between Pt sites in the square-planar Pt units. The long Pt-Pt distances and nonparallel orientation of Pt square planes prohibit metallophilic interactions within MPS. The combination of ultra-wideline NMR, pXRD, and computational methods offers much promise for future investigation and characterization of Pt-containing systems.

  4. Internal Magnus effects in superfluid 3He-A

    NASA Astrophysics Data System (ADS)

    Salmelin, R. H.; Salomaa, M. M.; Mineev, V. P.

    The orbital angular momentum of the coherently aligned Cooper pairs in superfluid (3)He-A is transmitted to an object immersed in the condensate. The authors evaluate the quasiparticle-scattering asymmetry experienced by a negative ion; this leads to a measurable, purely quantum-mechanical Magnus force deflecting the ion's trajectory. Close to T(sub c), possible hydrodynamic Magnus effects are smaller by the factor delta sub A/(k sub B)(T sub c).

  5. The Magnus Effect in Theory and in Reality

    NASA Technical Reports Server (NTRS)

    Ahlborn, F

    1930-01-01

    A discussion of the Flettner rotor is presented from a nautical and economic viewpoint, and although it was a failure, the experimental and theoretical inventions cannot be disregarded. The following critical and experimental investigation will show the relations and applicability of the theories and practical applications. The Magnus effect is described in detail and a discussion and critical review of the Magnus effect is included.

  6. Magnus force in discrete and continuous two-dimensional superfluids

    SciTech Connect

    Gecse, Z.; Khlebnikov, S.

    2005-08-01

    Motion of vortices in two-dimensional superfluids in the classical limit is studied by solving the Gross-Pitaevskii equation numerically on a uniform lattice. We find that, in the presence of a superflow directed along one of the main lattice periods, vortices move with the superflow on fine lattices but perpendicular to it on coarse ones. We interpret this result as a transition from the full Magnus force in a Galilean-invariant limit to vanishing effective Magnus force in a discrete system, in agreement with the existing experiments on vortex motion in Josephson junction arrays.

  7. STS-112 M.S. Magnus suits up for launch

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. --STS-112 Mission Specialist Sandra Magnus dons her space helmet for a final fit check in preparation for her launch to the International Space Station aboard Atlantis. Launch is scheduled for Oct. 2 between 2 and 6 p.m. EDT.

  8. STS-112 M.S. Magnus suits up for launch

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. --STS-112 Mission Specialist Sandra Magnus dons her spacesuit for a final fit check in preparation for her launch to the International Space Station aboard Atlantis. Launch is scheduled for Oct. 2 between 2 and 6 p.m. EDT.

  9. Describing neutrino oscillations in matter with Magnus expansion

    NASA Astrophysics Data System (ADS)

    Ioannisian, A. N.; Smirnov, A. Yu.

    2009-07-01

    We present new formalism for description of the neutrino oscillations in matter with varying density. The formalism is based on the Magnus expansion and has a virtue that the unitarity of the S-matrix is maintained in each order of perturbation theory. We show that the Magnus expansion provides better convergence of series: the restoration of unitarity leads to smaller deviations from the exact results especially in the regions of large transition probabilities. Various expansions are obtained depending on a basis of neutrino states and a way one splits the Hamiltonian into the self-commuting and non-commuting parts. In particular, we develop the Magnus expansion for the adiabatic perturbation theory which gives the best approximation. We apply the formalism to the neutrino oscillations in matter of the Earth and show that for the solar oscillation parameters the second order Magnus adiabatic expansion has better than 1% accuracy for all energies and trajectories. For the atmospheric Δm and small 1-3 mixing the approximation works well (<3% accuracy for sinθ=0.01) outside the resonance region 2.7-8 GeV.

  10. The "Magnus effect" - the principle of the Flettner rotor

    NASA Technical Reports Server (NTRS)

    Betz, A

    1925-01-01

    The phenomenon of the Magnus effect consists in the fact that a revolving body moving relatively to the surrounding fluid (air) is subjected not only to drag (i.e., a force acting in a direction opposite to that of the direction of motion), but also to a lift.

  11. Numerical simulation of negative Magnus force on a rotating sphere

    NASA Astrophysics Data System (ADS)

    Muto, Masaya; Tsubokura, Makoto; Oshima, Nobuyuki

    2010-11-01

    Flow characteristics and fluid force on a sphere rotating along with axis perpendicular to mean air flow were investigated using Large Eddy Simulation at two different Reynolds numbers of 10,000 and 200,000. As a result of simulation, opposite flow characteristics around the sphere and displacement of the separation point were visualized depending on the Reynolds number even though the sphere rotates at the same rotation speed according to the Reynolds number. When Reynolds number is 10,000, flow characteristics agree with the flow field explained in the Magnus effect. However sphere rotates at the same rotation speed while increasing Reynolds number to 200,000, separation point moves in opposite direction and wake appears in the different direction. The reason of the negative Magnus force was discussed in terms of the boundary layer transition on the surface.

  12. Magnus expansion and in-medium similarity renormalization group

    NASA Astrophysics Data System (ADS)

    Morris, T. D.; Parzuchowski, N. M.; Bogner, S. K.

    2015-09-01

    We present an improved variant of the in-medium similarity renormalization group (IM-SRG) based on the Magnus expansion. In the new formulation, one solves flow equations for the anti-Hermitian operator that, upon exponentiation, yields the unitary transformation of the IM-SRG. The resulting flow equations can be solved using a first-order Euler method without any loss of accuracy, resulting in substantial memory savings and modest computational speedups. Since one obtains the unitary transformation directly, the transformation of additional operators beyond the Hamiltonian can be accomplished with little additional cost, in sharp contrast to the standard formulation of the IM-SRG. Ground state calculations of the homogeneous electron gas (HEG) and 16O nucleus are used as test beds to illustrate the efficacy of the Magnus expansion.

  13. A review of the Magnus effect in aeronautics

    NASA Astrophysics Data System (ADS)

    Seifert, Jost

    2012-11-01

    The Magnus effect is well-known for its influence on the flight path of a spinning ball. Besides ball games, the method of producing a lift force by spinning a body of revolution in cross-flow was not used in any kind of commercial application until the year 1924, when Anton Flettner invented and built the first rotor ship Buckau. This sailboat extracted its propulsive force from the airflow around two large rotating cylinders. It attracted attention wherever it was presented to the public and inspired scientists and engineers to use a rotating cylinder as a lifting device for aircraft. This article reviews the application of Magnus effect devices and concepts in aeronautics that have been investigated by various researchers and concludes with discussions on future challenges in their application.

  14. Magnus effects at high angles of attack and critical Reynolds numbers

    NASA Technical Reports Server (NTRS)

    Seginer, A.; Ringel, M.

    1983-01-01

    The Magnus force and moment experienced by a yawed, spinning cylinder were studied experimentally in low speed and subsonic flows at high angles of attack and critical Reynolds numbers. Flow-field visualization aided in describing a flow model that divides the Magnus phenomenon into a subcritical region, where reverse Magnus loads are experienced, and a supercritical region where these loads are not encountered. The roles of the spin rate, angle of attack, and crossflow Reynolds number in determining the boundaries of the subcritical region and the variations of the Magnus loads were studied.

  15. A new 5-alkylresorcinol glucoside derivative from Cybianthus magnus.

    PubMed

    Cabanillas, B; Vásquez-Ocmín, P; Zebiri, I; Rengifo, E; Sauvain, M; Le, H L; Vaisberg, A; Voutquenne-Nazabadioko, L; Haddad, M

    2016-01-01

    One new 5-alkylresorcinol glucoside (1) was isolated from leaves of Cybianthus magnus, along with 12 known compounds (2-13), isolated from four plants belonging to Myrsinaceae family. Their structures were determined on the basis of spectroscopic analysis and by comparison of their spectral data with those reported in the literature. Among the tested molecules, only compound 2 displayed a strong cytotoxic activity with IC50 values ranging between 22 and 100 μM for all cell lines tested. One new 5-alkylresorcinol glucoside (1) was isolated from leaves of Cybianthus magnus, along with 12 known compounds, isolated from four plants belonging to Myrsinaceae family (2, 3 isolated from C. magnus; 4-7, 10 and 11 isolated from Myrsine latifolia; 4, 8 and 9 isolated from Myrsine sessiflora; 6, 7, 10, 12 and 13 isolated from Myrsine congesta). Their structures were determined on the basis of spectroscopic analysis and by comparison of their spectral data with those reported in the literature. So far, only nine 5-alkylresorcinol glucosides were isolated from leaves of Grevillea robusta. Since resorcinols are known to exhibit strong cytotoxic activity, compounds 1 and 2 were tested against cell lines 3T3, H460, DU145 and MCF-7 for cytotoxicity in vitro and compounds 3-13 were tested for their antileishmanial activity. Compound 2 displayed a strong cytotoxic activity with IC50 values ranging between 22 and 100 μM for all tested cell lines. Compounds 3-13 were not active against Leishmania amazonensis amastigotes.

  16. STS-112 M.S. Magnus suits up before launch

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- STS-112 Mission Specialist Sandra Magnus finishes suiting up before launch. STS-112 is the 15th assembly flight to the International Space Station, carrying the S1 Integrated Truss Structure and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts. On the 11-day mission, three spacewalks are planned to attach the S1 truss to the Station. Launch is scheduled for 3:46 p.m. EDT from Launch Pad 39B.

  17. A Magnus Expansion Analysis of Frequency-Dependent Mueller Matrices

    NASA Astrophysics Data System (ADS)

    Reimer, Michael; Yevick, David

    2006-03-01

    We have recently demonstrated that, for any physical system characterized by a non-singular, frequency dependent Jones matrix, the frequency evolution of the corresponding Mueller matrix is described by a differential equation whose general solution can be compactly formulated through the Magnus expansion [M. Reimer, D. Yevick, and D. Dumas, submitted to J. Opt. Soc. Am. A, Photon. Technol. Lett.]. [D. Yevick, T. Lu, W. Huang and W. Bardyszewski to be published in J. Opt. Soc. Am. A]. We subsequently applied our analytic results to optical compensators for communications networks and to the estimation of a system's frequency dependent Mueller matrix based on repeated measurements of the output state of polarization for randomly generated input polarization states [M. Reimer, D. Yevick and D. Dumas, submitted to Photon. Technol. Lett.]. We have also incorporated the Magnus expansion into a Clifford algebra description of polarization evolution. This procedure reformulates numerous physical transformations in a simple and transparent manner [M. Reimer and D. Yevick, submitted to Photon. Technol. Lett.].

  18. Numerical analysis of the Magnus moment on a spin-stabilized projectile

    NASA Astrophysics Data System (ADS)

    Cremins, Michael; Rodebaugh, Gregory; Verhulst, Claire; Benson, Michael; van Poppel, Bret

    2016-11-01

    The Magnus moment is a result of an uneven pressure distribution that occurs when an object rotates in a crossflow. Unlike the Magnus force, which is often small for spin-stabilized projectiles, the Magnus moment can have a strong detrimental effect on flight stability. According to one source, most transonic and subsonic flight instabilities are caused by the Magnus moment [Modern Exterior Ballistics, McCoy], and yet simulations often fail to accurately predict the Magnus moment in the subsonic regime. In this study, we present hybrid Reynolds Averaged Navier Stokes (RANS) and Large Eddy Simulation (LES) predictions of the Magnus moment for a spin-stabilized projectile. Velocity, pressure, and Magnus moment predictions are presented for multiple Reynolds numbers and spin rates. We also consider the effect of a sting mount, which is commonly used when conducting flow measurements in a wind tunnel or water channel. Finally, we present the initial designs for a novel Magnetic Resonance Velocimetry (MRV) experiment to measure three-dimensional flow around a spinning projectile. This work was supported by the Department of Defense High Performance Computing Modernization Program (DoD HPCMP).

  19. Vacancy-rearrangement theory in the first Magnus approximation

    SciTech Connect

    Becker, R.L.

    1984-01-01

    In the present paper we employ the first Magnus approximation (M1A), a unitarized Born approximation, in semiclassical collision theory. We have found previously that the M1A gives a substantial improvement over the first Born approximation (B1A) and can give a good approximation to a full coupled channels calculation of the mean L-shell vacancy probability per electron, p/sub L/, when the L-vacancies are accompanied by a K-shell vacancy (p/sub L/ is obtained experimentally from measurements of K/sub ..cap alpha../-satellite intensities). For sufficiently strong projectile-electron interactions (sufficiently large Z/sub p/ or small v) the M1A ceases to reproduce the coupled channels results, but it is accurate over a much wider range of Z/sub p/ and v than the B1A. 27 references.

  20. Drift of suspended ferromagnetic particles due to the Magnus effect

    NASA Astrophysics Data System (ADS)

    Denisov, S. I.; Pedchenko, B. O.

    2017-01-01

    A minimal system of equations is introduced and applied to study the drift motion of ferromagnetic particles suspended in a viscous fluid and subjected to a time-periodic driving force and a nonuniformly rotating magnetic field. It is demonstrated that the synchronized translational and rotational oscillations of these particles are accompanied by their drift in a preferred direction, which occurs under the action of the Magnus force. We calculate both analytically and numerically the drift velocity of particles characterized by single-domain cores and nonmagnetic shells and show that there are two types of drift, unidirectional and bidirectional, which can be realized in suspensions composed of particles with different core-shell ratios. The possibility of using the phenomenon of bidirectional drift for the separation of core-shell particles in suspensions is also discussed.

  1. Why adductor magnus muscle is large: the function based on muscle morphology in cadavers.

    PubMed

    Takizawa, M; Suzuki, D; Ito, H; Fujimiya, M; Uchiyama, E

    2014-02-01

    The aim of this study was to examine anatomical properties of the adductor magnus through a detailed classification, and to hypothesize its function and size to gather enough information about morphology. Ten cadaveric specimens of the adductor magnus were used. The muscle was separated into four portios (AM1-AM4) based on the courses of the corresponding perforating arteries, and its volume, muscle length, muscle fiber length and physiological cross-sectional area were assessed. The architectural characteristics of these four portions of the adductor magnus were then classified with the aid of principal component analysis. The results led us into demarcating the most proximal part of the adductor magnus (AM1) from the remaining parts (AM2, AM3, and AM4). Classification of the adductor magnus in terms of architectural characteristics differed from the more traditional anatomical distinction. The AM2, AM3, and AM4, having longer muscle fiber lengths than the AM1, appear to be designed as displacers for moving the thigh through a large range of motion. The AM1 appears instead to be oriented principally toward stabilizing the hip joint. The large mass of the adductor magnus should thus be regarded as a complex of functionally differentiable muscle portions.

  2. Role of transverse-momentum currents in the optical Magnus effect in free space

    SciTech Connect

    Luo Hailu; Wen Shuangchun; Shu Weixing; Fan Dianyuan

    2010-05-15

    We establish a general vector field model to describe the role of transverse-momentum currents in the optical Magnus effect in free space. As an analogy of the mechanical Magnus effect, the circularly polarized wave packet in our model acts as the rotating ball, and its rotation direction depends on the polarization state. Based on this model, we demonstrate the existence of an optical polarization-dependent Magnus effect which is significantly different from the conventional optical Magnus effect in that light-matter interaction is not required. Further, we reveal the relation between transverse-momentum currents and the optical Magnus effect, and find that such a polarization-dependent rotation is unavoidable when the wave packet possesses transverse-momentum currents. The physics underlying this intriguing effect is the combined contributions of transverse spin and orbital currents. We predict that this effect may be observed experimentally even in the propagation direction. These findings provide further evidence for the optical Magnus effect in free space and can be extrapolated to other physical systems.

  3. An anatomic and clinical study of the adductor magnus tendon-descending genicular artery bone flap.

    PubMed

    Huang, Dong; Wang, Hai-Wen; Xu, Da-Chuan; Wang, Hong-Gang; Wu, Wei-Zhi; Zhang, Hui-Ru

    2011-01-01

    The composite tissue flap of the descending genicular vessels with the adductor magnus tendon is a newly developed, reliable method to repair the Achilles tendon and relevant skin defects. The aim of this study was to evaluate the anatomy of the adductor magnus tendon-descending genicular artery bone flap, and the feasibility and value for the repair of the Achilles tendon and relevant skin defects. There were 34 adult specimens used for the anatomy of this flap. The descending genicular artery originates 10.5 ± 1.6 cm above the adductor tubercle, with a diameter of 1.8 ± 0.6 mm and a length of 1.2 ± 0.5 cm. Its articular branch is distributed in the adductor magnus tendon and the medial condyle of the femur. The saphenous branch has a diameter of 1.1 ± 0.3 mm and is distributed in the skin of the upper medial calf. A total of 16 cases of trauma-induced Achilles tendon damage and calcaneus and skin defects were repaired with the vascularized adductor magnus tendon bone flap, including the reconstruction of Achilles tendon insertion and repair of relevant skin defects. All of the composite tissue flaps were viable, the skin sensation of the flaps was recovered, and all patients walked with a normal gait. Our results suggested that the adductor magnus tendon-descending genicular artery bone flap is an alternative method to repair composite tissue defects of the Achilles tendon.

  4. Origin of the Magnus force on a vortex in fermion superfluids and superconductors

    SciTech Connect

    Simanek, E.

    1995-10-01

    Starting from the time-dependent version of the Feynman-Hellmann theorem, the Magnus force acting on a vortex in fermion superfluid is expressed via the adiabatic curvature over the space of vortex positions. With use of the Bogoliubov--de Gennes approximation, the Magnus force in a homogeneous superfluid at {ital T}=0 is shown to originate from virtual transitions between the lowest quasiparticle core bound states. Nonadiabatic corrections to the curvature are obtained to second order in vortex velocity. The adiabatic approximation is shown to break down at a critical velocity equal to the vortex velocity in the first Landau level. The effect of elastic scattering on the Magnus force is discussed in terms of the relaxation-time approximation. It is suggested that this approximation is appropriate only for a large-scale vortex motion. In this case, the effective Magnus force is drastically reduced when the elastic-scattering rate exceeds the core excitation frequency. We conjecture that quantum vortex tunneling is governed by a local Magnus force obtained from the Berry phase approach.

  5. Magnus-induced ratchet effects for skyrmions interacting with asymmetric substrates

    NASA Astrophysics Data System (ADS)

    Reichhardt, C.; Ray, D.; Olson Reichhardt, C. J.

    2015-07-01

    We show using numerical simulations that pronounced ratchet effects can occur for ac driven skyrmions moving over asymmetric quasi-one-dimensional substrates. We find a new type of ratchet effect called a Magnus-induced transverse ratchet that arises when the ac driving force is applied perpendicular rather than parallel to the asymmetry direction of the substrate. This transverse ratchet effect only occurs when the Magnus term is finite, and the threshold ac amplitude needed to induce it decreases as the Magnus term becomes more prominent. Ratcheting skyrmions follow ordered orbits in which the net displacement parallel to the substrate asymmetry direction is quantized. Skyrmion ratchets represent a new ac current-based method for controlling skyrmion positions and motion for spintronic applications.

  6. Asymmetry of the Venus nightside ionosphere: Magnus force effects

    NASA Astrophysics Data System (ADS)

    Pérez-de-Tejada, H.

    2008-11-01

    A study of the dawn-dusk asymmetry of the Venus nightside ionosphere is conducted by examining the configuration of the ionospheric trans-terminator flow around Venus and also the dawn-ward displacement of the region where most of the ionospheric holes and the electron density plateau profiles are observed (dawn meaning the west in the retrograde rotation of Venus and that corresponds to the trailing side in its orbital motion). The study describes the position of the holes and the density plateau profiles which occur at neighboring locations in a region that is scanned as the trajectory of the Pioneer Venus Orbiter (PVO) sweeps through the nightside hemisphere with increasing orbit number. The holes are interpreted as crossings through plasma channels that extend downstream from the magnetic polar regions of the Venus ionosphere and the plateau profiles represent cases in which the electron density maintains nearly constant values in the upper ionosphere along the PVO trajectory. From a collection of PVO passes in which these profiles were observed it is found that they appear at neighboring positions of the ionospheric holes in a local solar time (LST) map including cases where only a density plateau profile or an ionospheric hole was detected. It is argued that the ionospheric holes and the density plateau profiles have a common origin at the magnetic polar regions where plasma channels are formed and that the density plateau profiles represent crossings through a friction layer that is adjacent to the plasma channels. It is further suggested that the dawn-dusk asymmetry in the position of both features in the nightside ionosphere results from a fluid dynamic force (Magnus force) that is produced by the combined effects of the trans-terminator flow and the rotational motion of the ionosphere that have been inferred from the PVO measurements.

  7. Systematic Magnus-Based Approach for Suppressing Leakage and Nonadiabatic Errors in Quantum Dynamics

    NASA Astrophysics Data System (ADS)

    Ribeiro, Hugo; Baksic, Alexandre; Clerk, Aashish A.

    2017-01-01

    We present a systematic, perturbative method for correcting quantum gates to suppress errors that take the target system out of a chosen subspace. Our method addresses the generic problem of nonadiabatic errors in adiabatic evolution and state preparation, as well as general leakage errors due to spurious couplings to undesirable states. The method is based on the Magnus expansion: By correcting control pulses, we modify the Magnus expansion of an initially given, imperfect unitary in such a way that the desired evolution is obtained. Applications to adiabatic quantum state transfer, superconducting qubits, and generalized Landau-Zener problems are discussed.

  8. Effect of Magnus force on the scale deposition in geothermal systems

    SciTech Connect

    Michaelides, E.E.

    1981-12-01

    The Magnus lift force acts on solid particles present in vertical flows. The action of this force facilitates the mechanism of deposition. In upward flow (production wells), the turbulent fluctuations are necessary for the mechanism of deposition since they bring the particle into the laminar sublayer. In the downward flow, the Magnus force consistently acts toward the wall and turbulent fluctuations are no longer necessary for the mechanism of deposition. If the particle reaches the laminar sublayer, the forces acting on it will keep it near the wall until it is deposited. 10 refs.

  9. Anisotropic Magnus Force in Type-II Superconductors with Planar Defects

    NASA Astrophysics Data System (ADS)

    Monroy, Ricardo Vega; Gomez, Eliceo Cortés

    2015-02-01

    The effect of planar defects on the Magnus force in type-II superconductors is studied. It is shown that the deformation of the vortex due to the presence of a planar defect leads to a local decrease in the mean free path of electrons in the vortex. This effect reduces the effective Magnus coefficient in normal direction to the planar defect, leading to an anisotropic regime of the Hall effect. The presented developments here can qualitatively explain experimental observations of the anisotropic Hall effect in high- T c superconductors in the mixed state.

  10. Computations of the Magnus effect for slender bodies in supersonic flow

    NASA Technical Reports Server (NTRS)

    Sturek, W. B.; Schiff, L. B.

    1980-01-01

    A recently reported Parabolized Navier-Stokes code has been employed to compute the supersonic flow field about spinning cone, ogive-cylinder, and boattailed bodies of revolution at moderate incidence. The computations were performed for flow conditions where extensive measurements for wall pressure, boundary layer velocity profiles and Magnus force had been obtained. Comparisons between the computational results and experiment indicate excellent agreement for angles of attack up to six degrees. The comparisons for Magnus effects show that the code accurately predicts the effects of body shape and Mach number for the selected models for Mach numbers in the range of 2-4.

  11. Response to Yiannis Miralis, "Manos Hadjidakis: The Story of an Anarchic Youth and a "Magnus Eroticus"

    ERIC Educational Resources Information Center

    Serghi, Lenia

    2004-01-01

    Manos Hadjidakis and his work are like his song, "O Mythos," for they take you from reality to fantasy and bring you back again. In Magnus Eroticus, the combination of lyrics and music is at the highest level of sensibility and the musical style of each song is superb. Music follows the verse to express its deepest meaning while…

  12. Comparison among Magnus/Floquet/Fer expansion schemes in solid-state NMR

    SciTech Connect

    Takegoshi, K. Miyazawa, Norihiro; Sharma, Kshama; Madhu, P. K.

    2015-04-07

    We here revisit expansion schemes used in nuclear magnetic resonance (NMR) for the calculation of effective Hamiltonians and propagators, namely, Magnus, Floquet, and Fer expansions. While all the expansion schemes are powerful methods there are subtle differences among them. To understand the differences, we performed explicit calculation for heteronuclear dipolar decoupling, cross-polarization, and rotary-resonance experiments in solid-state NMR. As the propagator from the Fer expansion takes the form of a product of sub-propagators, it enables us to appreciate effects of time-evolution under Hamiltonians with different orders separately. While 0th-order average Hamiltonian is the same for the three expansion schemes with the three cases examined, there is a case that the 2nd-order term for the Magnus/Floquet expansion is different from that obtained with the Fer expansion. The difference arises due to the separation of the 0th-order term in the Fer expansion. The separation enables us to appreciate time-evolution under the 0th-order average Hamiltonian, however, for that purpose, we use a so-called left-running Fer expansion. Comparison between the left-running Fer expansion and the Magnus expansion indicates that the sign of the odd orders in Magnus may better be reversed if one would like to consider its effect in order.

  13. Negative Magnus lift on a rotating sphere at around the critical Reynolds number

    NASA Astrophysics Data System (ADS)

    Muto, Masaya; Tsubokura, Makoto; Oshima, Nobuyuki

    2012-01-01

    Negative Magnus lift acting on a sphere rotating about the axis perpendicular to an incoming flow was investigated using large-eddy simulation at three Reynolds numbers of 1.0 × 104, 2.0 × 105, and 1.14 × 106. The numerical methods used were first validated on a non-rotating sphere, and the spatial resolution around the sphere was determined so as to reproduce the laminar separation, reattachment, and turbulent transition of the boundary layer observed in the vicinity of the critical Reynolds number. The rotating sphere exhibited a positive or negative Magnus effect depending on the Reynolds number and the imposed rotating speed. At Reynolds numbers in the subcritical or supercritical regimes, the direction of the Magnus lift force was independent of the rotational speed. In contrast, the lift force was negative in the critical regime when particular rotating speeds were imposed. This negative Magnus effect was investigated in the context of suppression or promotion of boundary layer transition around the separation point.

  14. Comparison among Magnus/Floquet/Fer expansion schemes in solid-state NMR

    NASA Astrophysics Data System (ADS)

    Takegoshi, K.; Miyazawa, Norihiro; Sharma, Kshama; Madhu, P. K.

    2015-04-01

    We here revisit expansion schemes used in nuclear magnetic resonance (NMR) for the calculation of effective Hamiltonians and propagators, namely, Magnus, Floquet, and Fer expansions. While all the expansion schemes are powerful methods there are subtle differences among them. To understand the differences, we performed explicit calculation for heteronuclear dipolar decoupling, cross-polarization, and rotary-resonance experiments in solid-state NMR. As the propagator from the Fer expansion takes the form of a product of sub-propagators, it enables us to appreciate effects of time-evolution under Hamiltonians with different orders separately. While 0th-order average Hamiltonian is the same for the three expansion schemes with the three cases examined, there is a case that the 2nd-order term for the Magnus/Floquet expansion is different from that obtained with the Fer expansion. The difference arises due to the separation of the 0th-order term in the Fer expansion. The separation enables us to appreciate time-evolution under the 0th-order average Hamiltonian, however, for that purpose, we use a so-called left-running Fer expansion. Comparison between the left-running Fer expansion and the Magnus expansion indicates that the sign of the odd orders in Magnus may better be reversed if one would like to consider its effect in order.

  15. Comparison among Magnus/Floquet/Fer expansion schemes in solid-state NMR.

    PubMed

    Takegoshi, K; Miyazawa, Norihiro; Sharma, Kshama; Madhu, P K

    2015-04-07

    We here revisit expansion schemes used in nuclear magnetic resonance (NMR) for the calculation of effective Hamiltonians and propagators, namely, Magnus, Floquet, and Fer expansions. While all the expansion schemes are powerful methods there are subtle differences among them. To understand the differences, we performed explicit calculation for heteronuclear dipolar decoupling, cross-polarization, and rotary-resonance experiments in solid-state NMR. As the propagator from the Fer expansion takes the form of a product of sub-propagators, it enables us to appreciate effects of time-evolution under Hamiltonians with different orders separately. While 0th-order average Hamiltonian is the same for the three expansion schemes with the three cases examined, there is a case that the 2nd-order term for the Magnus/Floquet expansion is different from that obtained with the Fer expansion. The difference arises due to the separation of the 0th-order term in the Fer expansion. The separation enables us to appreciate time-evolution under the 0th-order average Hamiltonian, however, for that purpose, we use a so-called left-running Fer expansion. Comparison between the left-running Fer expansion and the Magnus expansion indicates that the sign of the odd orders in Magnus may better be reversed if one would like to consider its effect in order.

  16. Analgesia induced by morphine microinjected into the nucleus raphe magnus: effects on tonic pain.

    PubMed

    Dualé, Christian; Sierralta, Fernando; Dallel, Radhouane

    2007-07-01

    One of the possible sites of action of the analgesic effect of morphine is the Nucleus Raphe Magnus, as morphine injected into this structure induces analgesia in transient pain models. In order to test if morphine in the Nucleus Raphe Magnus is also analgesic in a tonic pain model, 5 microg of morphine or saline (control) were microinjected into the Nucleus Raphe Magnus of the rat. Analgesic effects were assessed following nociceptive stimulation using transient heating of the tail (phasic pain) and subcutaneous orofacial injection of 1.5 % formalin (tonic pain). While morphine was strongly analgesic for the tail-flick response (p <0.0001 compared to control), analgesia on the response to formalin was also observed for both early (p = 0.007) and late responses (p = 0.02). However, the response to formalin was not completely blunted. These results suggest that the Nucleus Raphe Magnus is not the exclusive site of action of morphine-induced analgesia in clinical conditions.

  17. Negative Magnus Effect on a Rotating Sphere at around the Critical Reynolds Number

    NASA Astrophysics Data System (ADS)

    Muto, Masaya; Watanabe, Hiroaki; Tsubokura, Makoto; Oshima, Nobuyuki

    2011-12-01

    Negative Magnus lift acting on a sphere rotating about the axis perpendicular to an incoming flow is investigated using large-eddy simulation at three Reynolds numbers of 1.0× 104, 2.0 × 105, and 1.14 × 106. The numerical methods adopted are first validated on a non-rotating sphere and the spatial resolution around the sphere is determined so as to reproduce the laminar separation, reattachment, and turbulent transition of the boundary layer observed at around the critical Reynolds number. In the rotating sphere, positive or negative Magnus effect is observed depending on the Reynolds number and the rotating speed imposed. At the Reynolds number in the subcritical or supercritical region, the direction of the lift force follows the Magnus effect to be independent of the rotational speed tested here. In contrast, negative lift is observed at the Reynolds number at the critical region when particular rotating speeds are imposed. The negative Magnus effect is discussed in the context of the suppression or promotion of boundary layer transition around the separation point.

  18. Simulation of Effects of the Saffman Force and the Magnus Force on Sand Saltation in Turbulent Flow

    SciTech Connect

    Zheng, Zhongquan C.; Zou, Xueyong; Yang, Xiaofan; Cheng, Hong

    2011-12-11

    The effects of both the Saffman force and Magnus force on sand saltation are investigated. Turbulent flows in a channel and over a barchans dune are considered with sand particles injected into the flow. The results show that both of the forces increase the height and skipping distance of sand saltation, with the Magnus force giving more significant effect on the height. These forces can also increase the sand settling at the lee side of the barchans dune.

  19. The tripartite origins of the tonic neck reflex: Gesell, Gerstmann, and Magnus.

    PubMed

    Shevell, Michael

    2009-03-03

    The standard neurologic examination of the newborn and infant includes the elicitation of the tonic neck reflex. Normally present, its persistence is suggestive of neurologic dysfunction and a prognostic marker highly suggestive of an adverse outcome. Working in different fields, with different approaches and largely independently, three leaders of early 20th century neurosciences (Rudolf Magnus, Josef Gerstmann, and Arnold Gesell) elaborated different aspects of this primitive reflex. Magnus provided the first description in an animal model utilizing a meticulously prepared decerebrate cat correctly identifying the reflex's reliance on proprioceptors in the neck and processing in the upper cervical segment. Gerstmann first described its occurrence in the setting of neurologic disease, providing a meticulous written description in an early description of the index case of what would later be eponymously designated Gerstmann-Straussler-Scheinker syndrome. Gesell initially described the reflex's fundamental occurrence in normal young infants, highlighting its adaptive role in early development and its persistence as a hallmark of neurologic pathology.

  20. [Local GABA-ergic modulation of serotonergic neuron activity in the nucleus raphe magnus].

    PubMed

    Iniushkin, A N; Merkulova, N A; Orlova, A O; Iniushkina, E M

    2009-07-01

    In voltage-clamp experimental on slices of the rat brainstem the effects of 5-HT and GABA on serotonergic neurons of nucleus raphe magnus were investigated. Local applications of 5-HT induced an increase in IPCSs frequency and amplitude in 45% of serotonergic cells. The effect suppressed by the blocker of fast sodium channels tetradotoxin. Antagonist of GABA receptor gabazine blocked IPSCs in neurons both sensitive and non-sensitive to 5-HT action. Applications of GABA induced a membrane current (I(GABA)), which was completely blocked by gabazine. The data suggest self-control of the activity of serotonergic neurons in nucleus raphe magnus by negative feedback loop via local GABAergic interneurons.

  1. The Magnus expansion and the in-medium similarity renormalization group

    NASA Astrophysics Data System (ADS)

    Morris, T. D.; Bogner, S. K.

    2014-10-01

    We present a variant of the in-medium similarity renormalization group(IMSRG) based on the Magnus expansion. In this new variant, the unitary transformation of the IMSRG is constructed explicitly, which allows for the transformation of observables quickly and easily. Additionally, the stiffness of equations encountered by the traditional solution of the IMSRG can be alleviated greatly. We present results and comparisons for the 3d electron gas.

  2. The Magnus-Rademaker Scientific Film Collection: Ethical Issues on Animal Experimentation (1908-1940).

    PubMed

    Koehler, Peter J; Lameris, Bregt

    2016-01-01

    The Magnus-Rademaker scientific film collection (1908-1940) deals with the physiology of body posture by the equilibrium of reflex musculature contractions for which experimental studies were carried out with animals (e.g., labyrinthectomies, cerebellectomies, and brain stem sections) as well as observations done on patients. The films were made for demonstrations at congresses as well as educational objectives and film stills were published in their books. The purpose of the present study is to position these films and their makers within the contemporary discourse on ethical issues and animal rights in the Netherlands and the earlier international debates. Following an introduction on animal rights and antivivisection movements, we describe what Magnus and Rademaker thought about these issues. Their publications did not provide much information in this respect, probably reflecting their adherence to implicit ethical codes that did not need explicit mentioning in publications. Newspaper articles, however, revealed interesting information. Unnecessary suffering of an animal never found mercy in Magnus' opinion. The use of cinematography was expanded to the reduction of animal experimentation in student education, at least in the case of Rademaker, who in the 1930s was involved in a governmental committee for the regulation of vivisection and cooperated with the antivivisection movement. This resulted not only in a propaganda film for the movement but also in films that demonstrate physiological experiments for students with the purpose to avert repetition and to improve the teaching of experiments. We were able to identify the pertinent films in the Magnus-Rademaker film collection. The production of vivisection films with this purpose appears to have been common, as is shown in news messages in European medical journals of the period.

  3. Magnus-induced dynamics of driven skyrmions on a quasi-one-dimensional periodic substrate

    NASA Astrophysics Data System (ADS)

    Reichhardt, C.; Reichhardt, C. J. Olson

    2016-09-01

    We numerically examine driven skyrmions interacting with a periodic quasi-one-dimensional substrate where the driving force is applied either parallel or perpendicular to the substrate periodicity direction. For perpendicular driving, the particles in a purely overdamped system simply slide along the substrate minima; however, for skyrmions where the Magnus force is relevant, we find that a rich variety of dynamics can arise. In the single skyrmion limit, the skyrmion motion is locked along the driving or longitudinal direction for low drives, while at higher drives a transition occurs to a state in which the skyrmion moves both transverse and longitudinal to the driving direction. Within the longitudinally locked phase we find a pronounced speedup effect that occurs when the Magnus force aligns with the external driving force, while at the transition to transverse and longitudinal motion, the skyrmion velocity drops, producing negative differential conductivity. For collectively interacting skyrmion assemblies, the speedup effect is still present and we observe a number of distinct dynamical phases, including a sliding smectic phase, a disordered or moving liquid phase, a moving hexatic phase, and a moving crystal phase. The transitions between the dynamic phases produce distinct features in the structure of the skyrmion lattice and in the velocity-force curves. We map these different phases as a function of the ratio of the Magnus term to the dissipative term, the substrate strength, the commensurability ratio, and the magnitude of the driving force.

  4. Chemical composition, larvicidal action, and adult repellency of Thymus magnus against Aedes albopictus.

    PubMed

    Park, Young-Uk; Koo, Hyun-Na; Kim, Gil-Hah

    2012-09-01

    Thymus magnus, an endemic species, is found in the Republic of Korea. The volatile compounds extracted by SPME from T. magnus were investigated for their chemical composition and electrophysiological response against the Asian tiger mosquito, Aedes albopictus. The volatile compounds of T. magnus as determined by gas chromatography mass spectrometry were gamma-terpinene (33.0%), thymol (29.9%), beta-bisabolene (8.9%), p-cymene (8.3%), alpha-terpinene (5.0%), myrcene (4.7%), beta-caryophyllene (4.0%), alpha-thujene (2.7%), camphene (1.3%), carvacrol (1.2%), and alpha-pinene (1.1%). Among these candidates, thymol exhibited complete (100%) repellent activity against female Ae. albopictus, an effect that was confirmed through evaluating the electrophysiological response on the antenna of Ae. albopictus. The effectiveness of a binary 1:2 mixture of thymol and vanillin (0.05:0.1 microl per cm2) was found to be significantly more effective than thymol alone for a period of 120 min. In addition, thymol, alpha-terpinene, and carvacrol showed high larvicidal activity against on the third-stage larvae with LC50 values of 0.9 microl per 100 ml.

  5. Curveballs in protoplanetary discs - the effect of the Magnus force on planet formation

    NASA Astrophysics Data System (ADS)

    Forbes, John C.

    2015-10-01

    Spinning planetesimals in a gaseous protoplanetary disc may experience a hydrodynamical force perpendicular to their relative velocities. We examine the effect this force has on the dynamics of these objects using analytical arguments based on a simple laminar disc model and numerical integrations of the equations of motion for individual grains. We focus in particular on metre-sized boulders traditionally expected to spiral in to the central star in as little as 100 years from 1 au We find that there are plausible scenarios in which this force extends the lifetime of these solids in the disc by a factor of several. More importantly the velocities induced by the Magnus force can prevent the formation of planetesimals via gravitational instability in the inner disc if the size of the dust particles is larger than of the order of 10 cm. We find that the fastest growing linear modes of the streaming instability may still grow despite the diffusive effect of the Magnus force, but it remains to be seen how the Magnus force will alter the non-linear evolution of these instabilities.

  6. Magnus expansion paradoxes in the study of equilibrium magnetization and entanglement in multi-pulse spin locking

    NASA Astrophysics Data System (ADS)

    Kuznetsova, E. I.; Fel'dman, E. B.; Feldman, D. E.

    2016-06-01

    Divergence of the Magnus expansion leads to paradoxes in the spin dynamics of solid-state NMR and in quantum informatics. This review presents results on quasi-equilibrium magnetization in a system of dipole-dipole (DD) coupled spins at times T_2\\ll t \\ll T1ρ in multiple-pulse spin locking ( T_2 is the transverse spin relaxation time and T1ρ is the rotating-frame spin-lattice relaxation time). It is shown how contradictions between the results obtained with the Magnus expansion and experimental data can be removed. Systems of two and three DD coupled spins in multi-pulse spin locking are considered, and the entanglement evolution is investigated using both the Magnus expansion and the exact solution. The critical temperature for an entangled state is also found.

  7. Floquet-Magnus expansion for general N-coupled spins systems in magic-angle spinning nuclear magnetic resonance spectra

    NASA Astrophysics Data System (ADS)

    Mananga, Eugene Stephane; Charpentier, Thibault

    2015-04-01

    In this paper we present a theoretical perturbative approach for describing the NMR spectrum of strongly dipolar-coupled spin systems under fast magic-angle spinning. Our treatment is based on two approaches: the Floquet approach and the Floquet-Magnus expansion. The Floquet approach is well known in the NMR community as a perturbative approach to get analytical approximations. Numerical procedures are based on step-by-step numerical integration of the corresponding differential equations. The Floquet-Magnus expansion is a perturbative approach of the Floquet theory. Furthermore, we address the " γ -encoding" effect using the Floquet-Magnus expansion approach. We show that the average over " γ " angle can be performed for any Hamiltonian with γ symmetry.

  8. Neurocinematography in Pre-World War II Netherlands: The Magnus-Rademaker Collection.

    PubMed

    Koehler, Peter J; Lameris, Bregt; Hielscher, Eva

    2016-01-01

    Historical films made by neuroscientists have shown up in several countries during past years. Although originally supposed to have been lost, we recently found a collection of films produced between 1909 and 1940 by Rudolf Magnus (1873-1927), professor of pharmacology (Utrecht) and his student Gysbertus Rademaker (1887-1957), professor of physiology (1928, succeeding Willem Einthoven) and neurology (1945, both in Leiden). Both collections deal with the physiology of body posture by the equilibrium of reflex musculature contractions for which experimental studies were done with animals (labyrinthectomies, cerebellectomies, and brainstem sections) and observations on patients. The films demonstrate the results of these studies. Moreover, there are films with babies showing tonic neck reflexes and moving images capturing adults with cerebellar symptoms following cerebellectomies for tumors and several other conditions. Magnus' studies resulted in his well-known Körperstellung (1924, "Body Posture") and Rademaker's research in his Das Stehen (1931, "Standing"). The films probably had an educative and scientific purpose. Magnus demonstrated his films at congresses, including the Eighth International Congress of Physiologists (Vienna, 1910) and Rademaker screened his moving images at meetings of the Amsterdam Neurologists Society (at several occasions as reflected in the Winkler-Monakow correspondence and the Nederlands Tijdschrift voor Geneeskunde). Next to these purposes, the films were used to analyze movement and a series of images from the films were published in articles and books. The films are important historical sources that provide a portrait of the pre-World War II era in neuroscience, partly answering questions on how physicians dealt with patients and researchers with their laboratory animals. Moreover, the films confirm that cinematography was an important scientific tool in neuroscience research.

  9. On the inverse Magnus effect for flow past a rotating cylinder

    NASA Astrophysics Data System (ADS)

    John, Benzi; Gu, Xiao-Jun; Barber, Robert W.; Emerson, David R.

    2016-11-01

    Flow past a rotating cylinder has been investigated using the direct simulation Monte Carlo method. The study focuses on the occurrence of the inverse Magnus effect under subsonic flow conditions. In particular, the variations in the coefficients of lift and drag have been investigated as a function of the Knudsen and Reynolds numbers. Additionally, a temperature sensitivity study has been carried out to assess the influence of the wall temperature on the computed aerodynamic coefficients. It has been found that both the Reynolds number and the cylinder wall temperature significantly affect the drag as well as the onset of lift inversion in the transition flow regime.

  10. The results of adductor magnus tenodesis in adolescents with recurrent patellar dislocation.

    PubMed

    Malecki, Krzysztof; Fabis, Jaroslaw; Flont, Pawel; Niedzielski, Kryspin Ryszard

    2015-01-01

    Recurrent dislocation of the patella is a common orthopaedic problem which occurs in about 44% of cases after first-time dislocation. In most cases of first-time patellar dislocation, the medial patellofemoral ligament (MPFL) becomes damaged. Between 2010 and 2012, 33 children and adolescents (39 knees) with recurrent patellar dislocation were treated with MPFL reconstruction using the adductor magnus tendon. The aim of our study is to assess the effectiveness of this surgical procedure. The outcomes were evaluated functionally (Lysholm knee scale, the Kujala Anterior Knee Pain Scale, and isokinetic examination) and radiographically (Caton index, sulcus angle, congruence angle, and patellofemoral angle). Four patients demonstrated redislocation with MPFL graft failure, despite the fact that patellar tracking was found to be normal before the injury, and the patients had not reported any symptoms. Statistically significant improvements in Lysholm and Kujala scales, in patellofemoral and congruence angle, were seen (P < 0.001). A statistically significant improvement in the peak torque of the quadriceps muscle and flexor was observed for 60°/sec and 180°/sec angular velocities (P = 0.01). Our results confirm the efficacy of MPFL reconstruction using the adductor magnus tendon in children and adolescents with recurrent patellar dislocation.

  11. Effects of the Magnus and Saffman forces on the saltation trajectories of sand grain

    NASA Astrophysics Data System (ADS)

    Zou, Xue-Yong; Cheng, Hong; Zhang, Chun-Lai; Zhao, Yan-Zhi

    2007-10-01

    Saltating sand grains are the primary component of airborne sand and account for 75% of all sand transport flux. The saltation height and horizontal distance traveled by sand grains are key factors in sand-control engineering. In addition to gravity and aerodynamic drag, the Magnus and Saffman forces also play important roles in saltation. To quantify the magnitudes of these forces in saltation we used high-speed multi-flash photography to observe the movement of saltating sand grains in a wind tunnel; this proved to be an efficient technique for determining the movement and rotational velocities of grains of natural sand with grain sizes ranging from 0.2 to 0.3 mm and shear velocities ( u*) of 0.67, 0.83, and 0.87 m s - 1 . The rotational speed of saltating sand grains varied between 200 and 800 rev s - 1 ; mean clockwise and anticlockwise rotational speeds were nearly identical, and both increased with increasing saltation height. With saltation heights divided into 1 cm intervals, the rotational speeds followed a Lorentzian distribution. Calculations based on a saltation model showed that the maximum increases in saltation height and in horizontal distance due to the Magnus force were 10.2 and 24.9%, respectively. The rate of increase of both parameters increased with increasing lift-off angle. The maximum increases in saltation height and horizontal distance of sand grains caused by the Saffman force were only 4.6% and 3.7%, respectively.

  12. Nitric oxide in the nucleus raphe magnus modulates cutaneous blood flow in rats during hypothermia

    PubMed Central

    Arami, Masoumeh Kourosh; zade, Javad Mirnajafi; Komaki, Alireza; Amiri, Mahmood; Mehrpooya, Sara; Jahanshahi, Ali; Jamei, Behnam

    2015-01-01

    Objective(s): Nucleus Raphe Magnus (NRM) that is involved in the regulation of body temperature contains nitric oxide (NO) synthase. Considering the effect of NO on skin blood flow control, in this study, we assessed its thermoregulatory role within the raphe magnus. Materials and Methods: To this end, tail blood flow of male Wistar rats was measured by laser doppler following the induction of hypothermia. Results: Intra-NRM injection of SNP (exogenous NO donor, 0.1- 0.2 μl, 0.2 nM) increased the blood flow. Similarly, unilateral microinjection of glutamate (0.1- 0.2 μl, 2.3 nM) into the nucleus increased the blood flow. This effect of L-glutamate was reduced by prior intra NRM administration of NO synthase inhibitor NG-methyl-L-arginine or NG-nitro-L-arginine methyl ester (L-NAME, 0.1 µl, 100 nM). Conclusion: It is concluded that NO modulates the thermoregulatory response of NRM to hypothermia and may interact with excitatory amino acids in central skin blood flow regulation. PMID:26730333

  13. Numerical investigation of the effect of sphere dimples on the drag crisis and the Magnus effect

    NASA Astrophysics Data System (ADS)

    Li, Jing; Tsubokura, Makoto; Tsunoda, Masaya

    2015-11-01

    The present study investigates the flow over a golf ball and a smooth sphere around the critical Reynolds numbers under both stationary and self-spinning conditions by conducting Large-eddy simulations (LES) based on high resolution unstructured grids. For the stationary cases, the present calculation results validate the promotion of the drag crisis at a relatively lower Reynolds number due to the golf ball dimples. It also shows that the golf ball dimples have a limited effect on the time-dependent lateral force development in the subcritical regime, whereas the dimples are beneficial in suppressing the lateral force oscillations in the supercritical regimes. With spin parameter Γ = 0.1, the drag coefficients for the spinning smooth sphere increase slightly in all Reynolds number regimes when compared to the stationary cases, whereas for the spinning golf ball, the drag force decreases in the critical regime and increases in the supercritical regime. For both spinning models, the inverse Magnus effect was reproduced in the critical regime, whereas in the supercritical regime the ordinary Magnus force was generated. Relatively weaker lift forces were also observed in the cases of the spinning golf balls when compared to the spinning smooth spheres.

  14. 3-D magnetic field calculations for wiggglers using MAGNUS-3D

    SciTech Connect

    Pissanetzky, S.; Tompkins, P.

    1988-01-01

    The recent but steady trend toward increased magnetic and geometric complexity in the design of wigglers and undulators, of which tapered wigglers, hybrid structures, laced electromagnetic wigglers, magnetic cladding, twisters and magic structures are examples, has caused a need for reliable 3-D computer models and a better understanding of the behavior of magnetic systems in three dimensions. The capabilities of the MAGNUS-3D Group of Programs are ideally suited to solve this class of problems and provide insight into 3-D effects. MAGNUS-3D can solve any problem of Magnetostatics involving permanent magnets, linear or nonlinear ferromagnetic materials and electric conductors of any shape in space. The magnetic properties of permanent magnets are described by the complete nonlinear demagnetization curve as provided by the manufacturer, or, at the user's choice, by a simpler approximation involving the coercive force, the residual induction and the direction of magnetization. The ferromagnetic materials are described by a magnetization table and an accurate interpolation relation. An internal library with properties of common industrial steels is available. The conductors are independent of the mesh and are described in terms of conductor elements from an internal library.

  15. Observation of Intrinsic Magnus Force and Direct Detection of Chirality in Superfluid 3He-A

    NASA Astrophysics Data System (ADS)

    Ikegami, Hiroki; Tsutsumi, Yasumasa; Kono, Kimitoshi

    2015-04-01

    We report details of the observation of the intrinsic Magnus (IM) force acting on negative and positive ions trapped just below a free surface of the A phase of superfluid 3He (3He-A). From the transport measurements of the ions along the surface, we found that the IM force acts on both the negative and positive ions. We also demonstrate that the transport measurements could distinguish whether the surface is composed of a chiral monodomain or multiple chiral domains. For multiple chiral domains, the current of the ions was found to be irreproducible and unstable, which was reasonably explained by the formation of the chiral domain structure and the dynamics of the chiral domain walls. For chiral monodomains, the appearance ratio of chirality emerging upon cooling through the superfluid transition temperature was found to depend on the direction of the external magnetic field, which implies the existence of an unknown coupling between the chirality and the magnetic field.

  16. STS-112 M.S. Magnus in white room before launch

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. - -- In the White Room at Launch Pad 39B, STS-112 Mission Specialist Sandra H. Magnus, Ph.D., receives assistance with her spacesuit before boarding Space Shuttle Atlantis. Liftoff is schedued for 3:46 p.m. EDT. Along with a crew of six, Atlantis will carry the S1 Integrated Truss Structure and the Crew and Equipment Translation Aid (CETA) Cart A to the International Space Station (ISS). The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts. On the 11-day mission, three spacewalks are planned to attach the S1 truss.

  17. Magnus Hirschfeld, his biographies and the possibilities and boundaries of "biography" as "doing history.".

    PubMed

    Brennan, Toni; Hegarty, Peter

    2009-12-01

    This article considers the two major biographies of sexologist Magnus Hirschfeld, MD (1868-1935), an early campaigner for "gay rights" avant la lettre. Like him, his first biographer Charlotte Wolff (1897-1986) was a Jewish doctor who lived and worked in Weimar Republic Berlin and fled Germany when the Nazi regime came to power. When researching Hirschfeld's biography (published in English in 1986) Wolff met a librarian and gay activist, Manfred Herzer, who would eventually be a cofounder of the Gay Museum in Berlin and publish (in German, in 1992) the other major Hirschfeld biography currently available. Using, inter alia, the correspondence between Wolff and Herzer, the article aims to explore and interrogate the boundaries and possibilities of "biography" as a form of "doing history."

  18. Textual alchemy: the transformation of pseudo-Albertus Magnus's Semita recta into the Mirror of Lights.

    PubMed

    Grund, Peter

    2009-11-01

    This article explores the strategies of and the reasons behind the reworking of pseudo-Albertus Magnus's Semita recta into the Mirror of Lights. I argue that the redactor sought to provide a more comprehensive defence of the legitimacy of alchemy than found in the Semita recta. In the process of doing so, he reshaped the original text so as to present three units that addressed different parts of the alchemical opus: first, theory and justification of alchemy; second, basic information on substances and procedures; and, third, practice. The redactor employed sophisticated textual tools identical to those seen in scholastic texts. These strategies, I argue, constitute part of the redactor's attempt to bring authority and credibility to his project and to alchemy in general. Certainly, much more attention needs to be paid to these experiments of textual alchemy in order to understand the practice of alchemy in the late medieval period.

  19. Effect of arginine vasopressin in the nucleus raphe magnus on antinociception in the rat.

    PubMed

    Yang, Jun; Chen, Jian-Min; Liu, Wen-Yan; Song, Cao-You; Wang, Cheng-Hai; Lin, Bao-Cheng

    2006-09-01

    Previous work has shown that arginine vasopressin (AVP) regulates antinociception through brain nuclei rather than the spinal cord and peripheral organs. The present study investigated the nociceptive effect of AVP in the nucleus raphe magnus (NRM) of the rat. Microinjection of AVP into the NRM increased pain threshold in a dose-dependent manner, while local administration of AVP-receptor antagonist-d(CH2)5Tyr(Et)DAVP decreased the pain threshold. Pain stimulation elevated AVP concentration in the NRM perfuse liquid. NRM pretreatment with AVP-receptor antagonist completely reversed AVP's effect on pain threshold in the NRM. The data suggest that AVP in the NRM is involved in antinociception.

  20. The adductor part of the adductor magnus is innervated by both obturator and sciatic nerves.

    PubMed

    Takizawa, Megumi; Suzuki, Daisuke; Ito, Hajime; Fujimiya, Mineko; Uchiyama, Eiichi

    2014-07-01

    The hip adductor group, innervated predominantly by the obturator nerve, occupies a large volume of the lower limb. However, case reports of patients with obturator nerve palsy or denervation have described no more than minimal gait disturbance. Those facts are surprising, given the architectural characteristics of the hip adductors. Our aim was to investigate which regions of the adductor magnus are innervated by the obturator nerve and by which sciatic nerve and to consider the clinical implications. Twenty-one lower limbs were examined from 21 formalin-fixed cadavers, 18 males and 3 females. The adductor magnus was dissected and was divided into four parts (AM1-AM4) based on the locations of the perforating arteries and the adductor hiatus. AM1 was supplied solely by the obturator nerve. AM2, AM3, and AM4 received innervation from both the posterior branch of the obturator nerve and the tibial nerve portion of the sciatic nerve in 2 (9.5%), 20 (95.2%), and 6 (28.6%) of the cadavers, respectively. The double innervation in more than 90% of the AM3s is especially noteworthy. Generally, AM1-AM3 corresponds to the adductor part, traditionally characterized as innervated by the obturator nerve, and AM4 corresponds to the hamstrings part, innervated by the sciatic nerve. Here, we showed that the sciatic nerve supplies not only the hamstrings part but also the adductor part. These two nerves spread more widely than has generally been believed, which could have practical implications for the assessment and treatment of motor disability.

  1. Metamaterials with tunable negative refractive index fabricated from nanoamorphous ferromagnetic microwires and Magnus optical effect

    NASA Astrophysics Data System (ADS)

    Ivanov, A.; Shalygin, A.; Galkin, V.; Vedyayev, A.; Rozanov, K.; Ivanov, V.

    2008-08-01

    For inhomogeneous mediums the optical Magnus effect has been derived. The metamaterials fabricated from amorphous ferromagnet Co-Fe-Cr-B-Si microwires are shown to exhibit a negative refractive index for electromagnetic waves over wide scale of GHz frequencies. Optical properties and optical Magnus effect of such metamaterials are tunable by an external magnetic field. Microwave permeability of glass-coated ferromagnetic amorphous microwire exhibiting a weak negative magnetostriction has been studied. The diameter of the microwire was about 20 μm and the diameter of the metal core was about 12 μm. The microwire was wound to comprise a 7/3 washer-shaped composite sample with the volume fraction of magnetic constituent of about 10%. The permeability of the composite sample was measured in a coaxial line in the frequency range from 0.1 to 10 GHz. The composite was found to exhibit a negative permeability within the frequency range from approximately 0.7 to 1.5 GHz, with the permeability being as low as -0.4. Therefore, microwire-based composites, particularly, crossed arrays of microwires may be employed to develop metamaterials for microwave applications. In the composite, the negative microwave permeability is due to the natural ferromagnetic resonance and the negative microwave permittivity is due to the inherent inductance of the wire. Such metamaterials are advantageous in simple design, isotropic in-plane performance, and possible tunability of performance by external magnetic bias. However, for a feasible metamaterial fabricated from microwire arrays, the wires have to exhibit higher magnitude of the ferromagnetic resonance, higher quality factor, and higher resonance frequency.

  2. Floquet–Magnus theory and generic transient dynamics in periodically driven many-body quantum systems

    SciTech Connect

    Kuwahara, Tomotaka; Mori, Takashi; Saito, Keiji

    2016-04-15

    This work explores a fundamental dynamical structure for a wide range of many-body quantum systems under periodic driving. Generically, in the thermodynamic limit, such systems are known to heat up to infinite temperature states in the long-time limit irrespective of dynamical details, which kills all the specific properties of the system. In the present study, instead of considering infinitely long-time scale, we aim to provide a general framework to understand the long but finite time behavior, namely the transient dynamics. In our analysis, we focus on the Floquet–Magnus (FM) expansion that gives a formal expression of the effective Hamiltonian on the system. Although in general the full series expansion is not convergent in the thermodynamics limit, we give a clear relationship between the FM expansion and the transient dynamics. More precisely, we rigorously show that a truncated version of the FM expansion accurately describes the exact dynamics for a certain time-scale. Our theory reveals an experimental time-scale for which non-trivial dynamical phenomena can be reliably observed. We discuss several dynamical phenomena, such as the effect of small integrability breaking, efficient numerical simulation of periodically driven systems, dynamical localization and thermalization. Especially on thermalization, we discuss a generic scenario on the prethermalization phenomenon in periodically driven systems. -- Highlights: •A general framework to describe transient dynamics for periodically driven systems. •The theory is applicable to generic quantum many-body systems including long-range interacting systems. •Physical meaning of the truncation of the Floquet–Magnus expansion is rigorously established. •New mechanism of the prethermalization is proposed. •Revealing an experimental time-scale for which non-trivial dynamical phenomena can be reliably observed.

  3. Investigation of the effect of finite pulse errors on the BABA pulse sequence using the Floquet-Magnus expansion approach

    NASA Astrophysics Data System (ADS)

    Mananga, Eugene S.; Reid, Alicia E.

    2013-01-01

    This paper presents a study of finite pulse widths for the BABA pulse sequence using the Floquet-Magnus expansion (FME) approach. In the FME scheme, the first order ? is identical to its counterparts in average Hamiltonian theory (AHT) and Floquet theory (FT). However, the timing part in the FME approach is introduced via the ? function not present in other schemes. This function provides an easy way for evaluating the spin evolution during the time in between' through the Magnus expansion of the operator connected to the timing part of the evolution. The evaluation of ? is particularly useful for the analysis of the non-stroboscopic evolution. Here, the importance of the boundary conditions, which provide a natural choice of ? , is ignored. This work uses the ? function to compare the efficiency of the BABA pulse sequence with ? and the BABA pulse sequence with finite pulses. Calculations of ? and ? are presented.

  4. Floquet resonant states and validity of the Floquet-Magnus expansion in the periodically driven Friedrichs models

    NASA Astrophysics Data System (ADS)

    Mori, Takashi

    2015-02-01

    The Floquet eigenvalue problem is analyzed for periodically driven Friedrichs models on discrete and continuous space. In the high-frequency regime, there exists a Floquet bound state consistent with the Floquet-Magnus expansion in the discrete Friedrichs model, while it is not the case in the continuous model. In the latter case, however, the bound state predicted by the Floquet-Magnus expansion appears as a metastable state whose lifetime diverges in the limit of large frequencies. We obtain the lifetime by evaluating the imaginary part of the quasienergy of the Floquet resonant state. In the low-frequency regime, there is no Floquet bound state and instead the Floquet resonant state with exponentially small imaginary part of the quasienergy appears, which is understood as the quantum tunneling in the energy space.

  5. A mini-invasive adductor magnus tendon transfer technique for medial patellofemoral ligament reconstruction: a technical note.

    PubMed

    Sillanpää, Petri J; Mäenpää, Heikki M; Mattila, Ville M; Visuri, Tuomo; Pihlajamäki, Harri

    2009-05-01

    Patellar dislocations are associated with injuries to the medial patellofemoral ligament (MPFL). Several techniques for MPFL reconstruction have been recently published with some disadvantages involved, including large skin incisions and donor site morbidity. Arthroscopic stabilizing techniques carry the potential of inadequate restoration of MPFL function. We present a minimally invasive technique for MPFL reconstruction using adductor magnus tendon autograft. This technique is easily performed, safe, and provides a stabilizing effect equal to current MPFL reconstructions. Skin incision of only 3-4 cm is located at the level of the proximal half of the patella. After identifying the distal insertion of the adductor magnus tendon, a tendon harvester is introduced to harvest the medial two-thirds of the tendon, while the distal insertion is left intact. The adductor magnus tendon is cut at 12-14 cm from its distal insertion and transferred into the patellar medial margin. Two suture anchors are inserted through the same incision at the superomedial aspect of the patella in the anatomic MPFL origin. The graft is tightened at 30 degrees knee flexion. Aftercare includes 4 weeks of brace treatment with restricted range of motion.

  6. Interaction of the topological phase and the Magnus effect in a multimode fiber

    NASA Astrophysics Data System (ADS)

    Aleksiev, A.; Modnikova, E.; Fadeyeva, Tatyana A.; Lapayeva, S. N.; Volyar, Alexander V.

    1996-04-01

    The phenomenon of a light topological birefringence in a multimode fiber has been discussed in papers. The physical mechanism of the topological birefringence, as expected earlier is determined by the interaction of the two effects, namely, the topological Berry's phase and the optical Magnus effect. So, for a square distribution of a refractive index in a fiber cross section the near-meridianal local waves propagate along ray trajectories represented by strongly stretched ellipses of an elliptical helix. A plane made by a fiber axis and a major axis of a ray elliptical helix undergoes a rotation into the fiber, and the rotation hand of this plane is defined by a sign of the wave polarization circularity. If a linear polarized light drops into a fiber input its left-hand polarized component will rotate the major axis of the elliptical helix counterclockwise, and the right-hand polarized component rotates clockwise. Since the angular rates of this rotation are slightly different one from another forthcoming the local waves having counter circulation of a polarization should be collapsed in a single linear polarized local wave. However if the local wave trajectory doesn't lie in a plane then it is a space curve.

  7. Introduction of the Floquet-Magnus expansion in solid-state nuclear magnetic resonance spectroscopy.

    PubMed

    Mananga, Eugène S; Charpentier, Thibault

    2011-07-28

    In this article, we present an alternative expansion scheme called Floquet-Magnus expansion (FME) used to solve a time-dependent linear differential equation which is a central problem in quantum physics in general and solid-state nuclear magnetic resonance (NMR) in particular. The commonly used methods to treat theoretical problems in solid-state NMR are the average Hamiltonian theory (AHT) and the Floquet theory (FT), which have been successful for designing sophisticated pulse sequences and understanding of different experiments. To the best of our knowledge, this is the first report of the FME scheme in the context of solid state NMR and we compare this approach with other series expansions. We present a modified FME scheme highlighting the importance of the (time-periodic) boundary conditions. This modified scheme greatly simplifies the calculation of higher order terms and shown to be equivalent to the Floquet theory (single or multimode time-dependence) but allows one to derive the effective Hamiltonian in the Hilbert space. Basic applications of the FME scheme are described and compared to previous treatments based on AHT, FT, and static perturbation theory. We discuss also the convergence aspects of the three schemes (AHT, FT, and FME) and present the relevant references.

  8. Vision and cognition in the natural philosophy of Albert the Great (Albertus Magnus).

    PubMed

    Theiss, P; Grüsser, O J

    1994-01-01

    Albert the Great (Albertus Magnus, ca. 1197-1280) descended from a nobleman's family in Upper Suebia and studied natural philosophy and theology at the University of Padova, where he joined the Dominican order. Confronted with Aristotelian thought mainly in its Arabic modification (Avicenna, Al-Farabi, Averroes, Alhazen, Costa ben Luca and others) from his days in Padova, he elaborated in several books on the principles of natural philosophy, biology, brain and sense functions and psychology in addition to his theological and exegetic works. His observations and concepts on vision are discussed in detail. It is pointed out that Albert discovered some phenomena of vision not before known such as vestibular nystagmus and rod monochromacy, i.e. total colour blindness accompanied by photophobia. Based on clinical observations Albert also postulated a decussation of the optic nerve fibres at the optic chiasm. Albert's concept of higher order cognitive function is discussed and some of his explanations of dreams and neuropsychiatric disease on the basis of his cognitive model are mentioned. Albert's thoughts on vision and other sense perceptions, higher brain functions and cognition are considered as progressive elaborations of Galenic concepts as adapted by some Patristic theologians and the Arabic natural scientists and philosophers of the 9th-11th century.

  9. Metamaterials with tunable refractive index fabricated from amorphous ferromagnetic microwires and optical Magnus effect

    NASA Astrophysics Data System (ADS)

    Ivanov, Andrey; Vedyayev, Anatoly; Galkin, Vladimir; Shalygin, Alexander; Ivanov, Valery

    2009-03-01

    For homogeneous NPVM (negative phase--velocity mediums) [V. G. Veselago, Soviet Physics - Uspekhi 10 (1968) 509; T. G. Mackay, A. Lakhtakia, Phys. Rev. E 69 (2004) 026602] anomalous effects such as negative refraction, light pressure, Doppler shift, Cherenkov-Vavilov radiation, Goos-Hanchen effect have been discovered in different frequency ranges. In this presentation the optical circular polarized effect is calculated for inhomogeneous mediums (optical Magnus effect) and it is shown that it is anomalous in NPVM with respect to ``right-handed'' materials. The proposed metamaterials fabricated from glass coated amorphous ferromagnetic Co-Fe-Cr-B-Si microwires are shown to exhibit a negative refractive index for electromagnetic waves over scale of GHz frequencies [A.V. Ivanov, A.N. Shalygin, A.V. Vedyayev, V.A. Ivanov, JETP Letters 85 (2007) 565]. The magnetostatic interaction between microwires has been taken into account. The phase and group velocities in proposed metamaterial have been calculated. The ratio of thereof depends monotonically on the size of the microwires. Optical properties of such metamaterials are tunable by an external magnetic field and mechanical stress.

  10. The Sexologist Albert Moll – between Sigmund Freud and Magnus Hirschfeld

    PubMed Central

    Sigusch, Volkmar

    2012-01-01

    Albert Moll was one of the most influential sexologists during the first three decades of the twentieth century. In contrast to his rivals Sigmund Freud and Magnus Hirschfeld, his achievements have not yet been recognised adequately. The author gives a comparative account of the work of these three protagonists. This shows that Moll formed some ideas which are regarded as psychoanalytical today before Freud, and that he, in contrast to Hirschfeld, was able to reflect critically on contemporary discourses, such as the debates on racial improvement through eugenics. As scientific theories, Freud’s psychoanalysis represented the unconscious, fantasy, experience and latency, while Moll’s sexology represented consciousness, ontological reality, behaviour and manifestation. Moll’s major disagreement with Hirschfeld’s sexology was his advocacy of apolitical and impartial science, whereas Hirschfeld’s aim was to achieve sexual reforms politically. Added to these differences were strong personal animosities. Freud called Moll a ‘beast’ and ‘pettifogger’; and Moll complained about Hirschfeld’s ‘problematic’ character. When Hirschfeld escaped the Nazi terror and went to Paris, Moll denounced him in order to prevent him rebuilding a new existence in exile. PMID:23002292

  11. An analysis of texture, timbre, and rhythm in relation to form in Magnus Lindberg's "Gran Duo"

    NASA Astrophysics Data System (ADS)

    Wolfe, Brian Thomas

    Gran Duo (1999-2000) by Magnus Lindberg (b. 1958) is the result of a commission by Sir Simon Rattle, former conductor of the City of Birmingham (England) Symphony Orchestra, and the Royal Festival Hall to commemorate the third millennium. Composed for twenty-four woodwinds and brass, Lindberg divides the woodwind and brass families into eight characters that serve as participants in an attentive twenty-minute conversation. The document includes biographical information about the composition to further understand Lindberg's writing style. The composer's use of computer-assisted composition techniques inspires an alternative structural analysis of Gran Duo. Spectral graphs provide a supplementary tool for score study assisting with the verification of formal structural elements. A tempo chart allows the conductor to easily identify form and tempo relationships between each of the nineteen sections throughout the five-movement composition. In order to reveal character areas and their relation to the structure of the work, the analysis of texture, timbre, and rhythm reveal the formal structure of the composition, which reflects a conversation between the brass and woodwinds in this setting for wind instruments.

  12. Black holes and fundamental fields: Hair, kicks, and a gravitational Magnus effect

    NASA Astrophysics Data System (ADS)

    Okawa, Hirotada; Cardoso, Vitor

    2014-11-01

    Scalar fields pervade theoretical physics and are a fundamental ingredient to solve the dark matter problem, to realize the Peccei-Quinn mechanism in QCD or the string-axiverse scenario. They are also a useful proxy for more complex matter interactions, such as accretion disks or matter in extreme conditions. Here, we study the collision between scalar "clouds" and rotating black holes. For the first time we are able to compare analytic estimates and strong field, nonlinear numerical calculations for this problem. As the black hole pierces through the cloud it accretes according to the Bondi-Hoyle prediction, but is deflected through a purely kinematic gravitational "anti-Magnus" effect, which we predict to be present also during the interaction of black holes with accretion disks. After the interaction is over, we find large recoil velocities in the transverse direction. The end-state of the process belongs to the vacuum Kerr family if the scalar is massless, but can be a hairy black hole when the scalar is massive.

  13. The sexologist Albert Moll--between Sigmund Freud and Magnus Hirschfeld.

    PubMed

    Sigusch, Volkmar

    2012-04-01

    Albert Moll was one of the most influential sexologists during the first three decades of the twentieth century. In contrast to his rivals Sigmund Freud and Magnus Hirschfeld, his achievements have not yet been recognised adequately. The author gives a comparative account of the work of these three protagonists. This shows that Moll formed some ideas which are regarded as psychoanalytical today before Freud, and that he, in contrast to Hirschfeld, was able to reflect critically on contemporary discourses, such as the debates on racial improvement through eugenics. As scientific theories, Freud's psychoanalysis represented the unconscious, fantasy, experience and latency, while Moll's sexology represented consciousness, ontological reality, behaviour and manifestation. Moll's major disagreement with Hirschfeld's sexology was his advocacy of apolitical and impartial science, whereas Hirschfeld's aim was to achieve sexual reforms politically. Added to these differences were strong personal animosities. Freud called Moll a 'beast' and 'pettifogger'; and Moll complained about Hirschfeld's 'problematic' character. When Hirschfeld escaped the Nazi terror and went to Paris, Moll denounced him in order to prevent him rebuilding a new existence in exile.

  14. Magnus Expansion Approach to Parametric Oscillator Systems in a Thermal Bath

    NASA Astrophysics Data System (ADS)

    Zhu, Beilei; Rexin, Tobias; Mathey, Ludwig

    2016-10-01

    We develop a Magnus formalism for periodically driven systems which provides an expansion both in the driving term and in the inverse driving frequency, applicable to isolated and dissipative systems. We derive explicit formulas for a driving term with a cosine dependence on time, up to fourth order. We apply these to the steady state of a classical parametric oscillator coupled to a thermal bath, which we solve numerically for comparison. Beyond dynamical stabilisation at second order, we find that the higher orders further renormalise the oscillator frequency, and additionally create a weakly renormalised effective temperature. The renormalised oscillator frequency is quantitatively accurate almost up to the parametric instability, as we confirm numerically. Additionally, a cut-off dependent term is generated, which indicates the break down of the hierarchy of time scales of the system, as a precursor to the instability. Finally, we apply this formalism to a parametrically driven chain, as an example for the control of the dispersion of a many-body system.

  15. Opioid microinjection into raphe magnus modulates cardiorespiratory function in mice and rats.

    PubMed

    Hellman, Kevin M; Mendelson, Scott J; Mendez-Duarte, Marco A; Russell, James L; Mason, Peggy

    2009-11-01

    The raphe magnus (RM) participates in opioid analgesia and contains pain-modulatory neurons with respiration-related discharge. Here, we asked whether RM contributes to respiratory depression, the most prevalent lethal effect of opioids. To investigate whether opioidergic transmission in RM produces respiratory depression, we microinjected a mu-opioid receptor agonist, DAMGO, or morphine into the RM of awake rodents. In mice, opioid microinjection produced sustained decreases in respiratory rate (170 to 120 breaths/min), as well as heart rate (520 to 400 beats/min). Respiratory sinus arrhythmia, indicative of enhanced parasympathetic activity, was prevalent in mice receiving DAMGO microinjection. We performed similar experiments in rats but observed no changes in breathing rate or heart rate. Both rats and mice experienced significantly more episodes of bradypnea, indicative of impaired respiratory drive, after opioid microinjection. During spontaneous arousals, rats showed less tachycardia after opioid microinjection than before microinjection, suggestive of an attenuated sympathetic tone. Thus, activation of opioidergic signaling within RM produces effects beyond analgesia, including the unwanted destabilization of cardiorespiratory function. These adverse effects on homeostasis consequent to opioid microinjection imply a role for RM in regulating the balance of sympathetic and parasympathetic tone.

  16. Floquet-Magnus theory and generic transient dynamics in periodically driven many-body quantum systems

    NASA Astrophysics Data System (ADS)

    Kuwahara, Tomotaka; Mori, Takashi; Saito, Keiji

    2016-04-01

    This work explores a fundamental dynamical structure for a wide range of many-body quantum systems under periodic driving. Generically, in the thermodynamic limit, such systems are known to heat up to infinite temperature states in the long-time limit irrespective of dynamical details, which kills all the specific properties of the system. In the present study, instead of considering infinitely long-time scale, we aim to provide a general framework to understand the long but finite time behavior, namely the transient dynamics. In our analysis, we focus on the Floquet-Magnus (FM) expansion that gives a formal expression of the effective Hamiltonian on the system. Although in general the full series expansion is not convergent in the thermodynamics limit, we give a clear relationship between the FM expansion and the transient dynamics. More precisely, we rigorously show that a truncated version of the FM expansion accurately describes the exact dynamics for a certain time-scale. Our theory reveals an experimental time-scale for which non-trivial dynamical phenomena can be reliably observed. We discuss several dynamical phenomena, such as the effect of small integrability breaking, efficient numerical simulation of periodically driven systems, dynamical localization and thermalization. Especially on thermalization, we discuss a generic scenario on the prethermalization phenomenon in periodically driven systems.

  17. Authigenic albite formation due to water-rock interactions - Case study: Magnus oilfield (UK, Northern North Sea)

    NASA Astrophysics Data System (ADS)

    Mu, Nana; Fu, Yunjiao; Schulz, Hans-Martin; van Berk, Wolfgang

    2016-01-01

    It is the aim of this contribution to test whether organic-inorganic interactions could induce the formation of authigenic albite. This concept and related results are being compared with modelling scenarios which are purely based on inorganic geochemical reactions. In order to unravel the pathway of authigenic albite formation, this paper presents results of a multidisciplinary study from imaging, geochemistry, mineralogy, and hydrogeochemical modelling. The Jurassic reservoir sandstones of the Magnus oilfield (UK, North Sea) were chosen as a test site. Albite occurs with 4-18 wt.% in the Magnus sandstones and its contents vary with depth. However, albite contents increase with increasing K-feldspar contents and decreasing grain size. It occurs in three forms: (1) as lamellae in perthite, (2) as overgrowth on/in corroded feldspar, and, (3) as cloudy replacing albite patches in K-feldspar. The albite overgrowth has the highest chemical purity (100% albite) whilst albite lamellae and replacing albite patches are slightly less pure (containing 1-4% anorthite). Albite appears non-altered, and has a euhedral morphology and dull cathodoluminescence. It commonly co-occurs with corroded K-feldspar grains. The precipitation of diagenetic albite in the Magnus sandstones is attributed to deep burial 80 Ma ago and may have continued until today at temperatures between 90-120 °C. The results of hydrogeochemical modelling offer two possible pathways for the authigenic albite formation: (1) Dissolution of unstable minerals (such as kaolinite and chalcedony) coupled to reduction of ferric iron minerals by products generated during oil generation, migration and degradation; (2) Dissolution of non-end member feldspar, such as K-feldspar with 10% albite, coupled to illite formation can account for trace amounts of albite due to an elevated Na+/K+ activity ratio in the pore water.

  18. Decrease in serotonin concentration in raphe magnus nucleus and attenuation of morphine analgesia in two mice models of neuropathic pain.

    PubMed

    Sounvoravong, Sourisak; Nakashima, Mihoko N; Wada, Mitsuhiro; Nakashima, Kenichiro

    2004-01-26

    The alleviation of neuropathic pain cannot be satisfactorily achieved by treatment with opioids. There is much evidence to indicate that the active site of morphine for inducing effective analgesia is in the raphe magnus nucleus, where serotonin (5-HT, 5-hydroxytryptamine) acts as a primary transmitter. Therefore, we developed the hypothesis that 5-HT released in the raphe magnus nucleus could be related to the effectiveness of morphine in two mice models of neuropathic pain, diabetic (DM)-induced neuropathy and sciatic nerve ligation (SL). Two weeks after a single administration of streptozotocin, or 10 days after sciatic nerve ligation, mice were subcutaneously (s.c.) injected with morphine at 3, 5 and 10 mg/kg. The antinociceptive effect of morphine was estimated in the tail-pinch test; 5-HT content was measured after induction of neuropathic pain by microdialysis followed by high-performance liquid chromatography with electrochemical detection (HPLC-ECD). Morphine produced as insufficient antinociceptive effect in SL mice at all doses compared with that in sham-operated mice, while in DM mice, morphine given s.c. at 5 and 10 mg/kg produced antinociceptive effects compared with those in non-diabetic mice, but not at 3 mg/kg. The 5-HT content of dialysates, expressed as AUC for 75 min, in SL and DM mice was less than that in control mice. However, morphine given s.c. at 5 mg/kg did not significantly affect 5-HT levels in both mice models compared to their controls. These results suggest that the decrease in 5-HT levels in the raphe magnus nucleus may be related to attenuation of the analgesic effect of morphine caused by the abnormal pain state found in diabetes and partial peripheral nerve injury.

  19. Neurotensin excitation of serotonergic neurons in the rat nucleus raphe magnus: ionic and molecular mechanisms.

    PubMed

    Li, A H; Yeh, T H; Tan, P P; Hwang, H M; Wang, H L

    2001-06-01

    To understand the cellular and molecular mechanisms by which neurotensin (NT) induces an analgesic effect in the nucleus raphe magnus (NRM), whole-cell patch-clamp recordings were performed to investigate the electrophysiological effects of NT on acutely dissociated NRM neurons. Two subtypes of neurons, primary serotonergic and secondary non-serotonergic cells, were identified from acutely isolated NRM neurons. During current-clamp recordings, NT depolarized NRM serotonergic neurons and evoked action potentials. Voltage-clamp recordings showed that NT excited serotonergic neurons by enhancing a voltage-insensitive and non-selective cationic conductance. Both SR48692, a selective antagonist of subtype 1 neurotensin receptor (NTR-1), and SR 142948A, a non-selective antagonist of NTR-1 and subtype 2 neurotensin receptor (NTR-2), failed to prevent neurotensin from exciting NRM serotonergic neurons. NT-evoked cationic current was inhibited by the intracellular administration of GDP-beta-S. NT failed to induce cationic currents after dialyzing serotonergic neurons with the anti-G(alphaq/11) antibody. Cellular Ca(2+) imaging study using fura-2 showed that NT induced the calcium release from the intracellular store. NT-evoked current was blocked after the internal perfusion of heparin, an IP(3) receptor antagonist, or BAPTA, a fast Ca(2+) chelator. It is concluded that neurotensin enhancement of the cationic conductance of NRM serotonergic neurons is mediated by a novel subtype of neurotensin receptors. The coupling mechanism via G(alphaq/11) proteins is likely to involve the generation of IP(3), and subsequent IP(3)-evoked Ca(2+) release from intracellular stores results in activating the non-selective cationic conductance.

  20. Tolerance to Non-Opioid Analgesics is Opioid Sensitive in the Nucleus Raphe Magnus.

    PubMed

    Tsagareli, Merab G; Nozadze, Ivliane; Tsiklauri, Nana; Gurtskaia, Gulnaz

    2011-01-01

    Repeated injection of opioid analgesics can lead to a progressive loss of effect. This phenomenon is known as tolerance. Several lines of investigations have shown that systemic, intraperitoneal administration or the microinjection of non-opioid analgesics, non-steroidal anti-inflammatory drugs (NSAIDs) into the midbrain periaqueductal gray matter induces antinociception with some effects of tolerance. Our recent study has revealed that microinjection of three drugs analgin, ketorolac, and xefocam into the central nucleus of amygdala produce tolerance to them and cross-tolerance to morphine. Here we report that repeated administrations of these NSAIDs into the nucleus raphe magnus (NRM) in the following 4 days result in progressively less antinociception compare to the saline control, i.e., tolerance develops to these drugs in male rats. Special control experiments showed that post-treatment with the μ-opioid antagonist naloxone into the NRM significantly decreased antinociceptive effects of NSAIDs on the first day of testing in the tail-flick (TF) reflex and hot plate (HP) latency tests. On the second day, naloxone generally had trend effects in both TF and HP tests and impeded the development of tolerance to the antinociceptive effect of non-opioid analgesics. These findings strongly support the suggestion of endogenous opioid involvement in NSAIDs antinociception and tolerance in the descending pain-control system. Moreover, repeated injections of NSAIDs progressively lead to tolerance to them, cross-tolerance to morphine, and the risk of a withdrawal syndrome. Therefore, these results are important for human medicine too.

  1. Increased glutamate synaptic transmission in the nucleus raphe magnus neurons from morphine-tolerant rats.

    PubMed

    Bie, Bihua; Pan, Zhizhong Z

    2005-02-09

    Currently, opioid-based drugs are the most effective pain relievers that are widely used in the treatment of pain. However, the analgesic efficacy of opioids is significantly limited by the development of tolerance after repeated opioid administration. Glutamate receptors have been reported to critically participate in the development and maintenance of opioid tolerance, but the underlying mechanisms remain unclear. Using whole-cell voltage-clamp recordings in brainstem slices, the present study investigated chronic morphine-induced adaptations in glutamatergic synaptic transmission in neurons of the nucleus raphe magnus (NRM), a key supraspinal relay for pain modulation and opioid analgesia. Chronic morphine significantly increased glutamate synaptic transmission exclusively in one class of NRM cells that contains mu-opioid receptors in a morphine-tolerant state. The adenylyl cyclase activator forskolin and the cAMP analog 8-bromo-cAMP mimicked the chronic morphine effect in control neurons and their potency in enhancing the glutamate synaptic current was significantly increased in neurons from morphine-tolerant rats. MDL12330a, an adenylyl cyclase inhibitor, and H89, a protein kinase A (PKA) inhibitor, reversed the increase in glutamate synaptic transmission induced by chronic morphine. In addition, PMA, a phorbol ester activator of protein kinase C (PKC), also showed an increased potency in enhancing the glutamate synaptic current in these morphine-tolerant cells. The PKC inhibitor GF109203X attenuated the chronic morphine effect. Taken together, these results suggest that chronic morphine increases presynaptic glutamate release in mu receptor-containing NRM neurons in a morphine-tolerant state, and that the increased glutamate synaptic transmission appears to involve an upregulation of both the cAMP/PKA pathway and the PKC pathway. This glutamate-mediated activation of these NRM neurons that are thought to facilitate spinal pain transmission may contribute to

  2. Influence of the magnus force on the motion of a spherical solid with a large angular velocity

    NASA Astrophysics Data System (ADS)

    Naumov, V. A.; Solomenko, A. D.; Yatsenko, V. P.

    1993-09-01

    The influence of the initial angular velocity imparted by an electric motor to a spherical solid on its deviation from the vertical in fall is investigated experimentally. Values of the coefficient CM in the formula for the Magnus force at which the trajectories of sphere motion are in agreement with the experimental data are found by calculation. It is established that as the Reynolds number Reω grows the coefficient CM decreases; with Reω˜3·104 CM is 10% of the quantity C{M/0} found by Rubinov and Keller for small Reynolds numbers.

  3. Vortex currents in turbulent superfluid and classical fluid channel flow, the magnus effect, and Goldstone boson fields

    SciTech Connect

    Huggins, E.R. )

    1994-09-01

    Expressing hydrodynamics in terms of the flow of vorticity, using the vortex current tensor, helps unify the picture of turbulent channel flow for viscous fluids and for superfluids. In both, eddy viscosity plays a major role in energy dissipation, and in both there is a similar cross stream flow of vorticity, which in the case of superfluids leads to the Josephson frequency. The vortex current tensor, which was introduced in an earlier paper to derive an exact three dimensional Magnus effect formula, turns out to be the classical hydrodynamic limit of the vortex current that is the source for a classical Goldstone-boson field.

  4. Reproductive cycle of Ensis magnus in the Ría de Pontevedra (NW Spain): Spatial variability and fisheries management implications

    NASA Astrophysics Data System (ADS)

    Hernández-Otero, A.; Martínez-Castro, C.; Vázquez, E.; Macho, G.

    2014-08-01

    Mesoscale differences in the reproductive cycle of the commercial sword razor clam Ensis magnus (Schumacher, 1817) were studied in six shellfish beds in the Ría de Pontevedra (NW Spain) between March 2008 and July 2010. The GCI accurately described the reproductive cycle as indicated by the histological analysis. Both methods showed that the reproductive cycle was similar at different sites and was characterized by a resting stage during summer and early autumn, initiation of gametogenesis in autumn and a period of successive spawning interspersed with gonad recovery during winter and spring. However, a 15-day to one month delay in advanced stages of gametogenesis and maturation was observed between the inner and the outermost site of the ria, as well as an extended spawning period in the outermost area. Lower bottom seawater temperatures at the outermost sites appeared to delay maturation and to prolong the spawning periods, whereas salinity fluctuations at the innermost sites appeared to reduce the length of the cycle. This study provides the first estimation of the size at which E. magnus reaches sexual maturity in the Iberian Peninsula, determined in 79 mm, and it is also the first work in determining the mesoscale variation in gonadal development of any species of the superfamily Solenoidea. The results highlight the importance of carrying out mesoscale studies of the reproductive biology in coastal fisheries resources. Some of the findings of the present study have already been applied in the rotation scheme of the fishery harvesting plan.

  5. Raphe magnus and reticulospinal actions on primary afferent depolarization of group I muscle afferents in the cat.

    PubMed

    Quevedo, J; Eguibar, J R; Jiménez, I; Rudomin, P

    1995-02-01

    1. In the anaesthetized cat, electrical stimulation of the bulbar reticular formation produced a short latency (2.1 +/- 0.3 ms) positive potential in the cord dorsum. In contrast, stimulation of the nucleus raphe magnus with strengths below 50 microA evoked a slow negative potential with a mean latency of 5.5 +/- 0.6 ms that persisted after sectioning the contralateral pyramid and was abolished by sectioning the ipsilateral dorsolateral funiculus. 2. The field potentials evoked by stimulation of the bulbar reticular formation and of the nucleus raphe magnus had a different intraspinal distribution, suggesting activation of different sets of segmental interneurones. 3. Stimulation of these two supraspinal nuclei produced primary afferent depolarization (PAD) in single Ib fibres and inhibited the PAD elicited by group I volleys in single Ia fibres. The inhibition of the PAD of Ia fibres produced by reticulospinal and raphespinal inputs appears to be exerted on different interneurones along the PAD pathway. 4. It is concluded that, although reticulospinal and raphespinal pathways have similar inhibitory effects on PAD of Ia fibres, and similar excitatory effects on the PAD of Ib fibres, their actions are conveyed by partly independent pathways. This would allow their separate involvement in the control of posture and movement.

  6. Raphe magnus and reticulospinal actions on primary afferent depolarization of group I muscle afferents in the cat.

    PubMed Central

    Quevedo, J; Eguibar, J R; Jiménez, I; Rudomin, P

    1995-01-01

    1. In the anaesthetized cat, electrical stimulation of the bulbar reticular formation produced a short latency (2.1 +/- 0.3 ms) positive potential in the cord dorsum. In contrast, stimulation of the nucleus raphe magnus with strengths below 50 microA evoked a slow negative potential with a mean latency of 5.5 +/- 0.6 ms that persisted after sectioning the contralateral pyramid and was abolished by sectioning the ipsilateral dorsolateral funiculus. 2. The field potentials evoked by stimulation of the bulbar reticular formation and of the nucleus raphe magnus had a different intraspinal distribution, suggesting activation of different sets of segmental interneurones. 3. Stimulation of these two supraspinal nuclei produced primary afferent depolarization (PAD) in single Ib fibres and inhibited the PAD elicited by group I volleys in single Ia fibres. The inhibition of the PAD of Ia fibres produced by reticulospinal and raphespinal inputs appears to be exerted on different interneurones along the PAD pathway. 4. It is concluded that, although reticulospinal and raphespinal pathways have similar inhibitory effects on PAD of Ia fibres, and similar excitatory effects on the PAD of Ib fibres, their actions are conveyed by partly independent pathways. This would allow their separate involvement in the control of posture and movement. Images Figure 6 PMID:7738852

  7. Investigation of the Effect of Finite Pulse Errors on BABA Pulse Sequence Using Floquet-Magnus Expansion Approach.

    PubMed

    Mananga, Eugene S; Reid, Alicia E

    This paper presents the study of finite pulse widths for the BABA pulse sequence using the Floquet-Magnus expansion (FME) approach. In the FME scheme, the first order F1 is identical to its counterparts in average Hamiltonian theory (AHT) and Floquet theory (FT). However, the timing part in the FME approach is introduced via the Λ1 (t) function not present in other schemes. This function provides an easy way for evaluating the spin evolution during "the time in between" through the Magnus expansion of the operator connected to the timing part of the evolution. The evaluation of Λ1 (t) is useful especially for the analysis of the non-stroboscopic evolution. Here, the importance of the boundary conditions, which provides a natural choice of Λ1 (0) is ignored. This work uses the Λ1 (t) function to compare the efficiency of the BABA pulse sequence with δ - pulses and the BABA pulse sequence with finite pulses. Calculations of Λ1 (t) and F1 are presented.

  8. Modified geometrical optics of a smoothly inhomogeneous isotropic medium: the anisotropy, Berry phase, and the optical Magnus effect.

    PubMed

    Bliokh, K Yu; Bliokh, Yu P

    2004-08-01

    We present a modification of the geometrical optics method, which allows one to properly separate the complex amplitude and the phase of the wave solution. Appling this modification to a smoothly inhomogeneous isotropic medium, we show that in the first geometrical optics approximation the medium is weakly anisotropic. The refractive index, being dependent on the direction of the wave vector, contains the correction, which is proportional to the Berry geometric phase. Two independent eigenmodes of right-hand and left-hand circular polarizations exist in the medium. Their group velocities and phase velocities differ. The difference in the group velocities results in the shift of the rays of different polarizations (the optical Magnus effect). The difference in the phase velocities causes an increase of the Berry phase along with the interference of two modes leading to the familiar Rytov law about the rotation of the polarization plane of a wave. The theory developed suggests that both the optical Magnus effect and the Berry phase are accompanying nonlocal topological effects. In this paper the Hamilton ray equations giving a unified description for both of these phenomena have been derived and also a novel splitting effect for a ray of noncircular polarization has been predicted. Specific examples are also discussed.

  9. Applications of Floquet-Magnus expansion, average Hamiltonian theory and Fer expansion to study interactions in solid state NMR when irradiated with the magic-echo sequence

    PubMed Central

    Mananga, Eugene Stephane

    2015-01-01

    This work presents the possibility of applying the Floquet-Magnus expansion and the Fer expansion approaches to the most useful interactions known in solid-state nuclear magnetic resonance using the magic-echo scheme. The results of the effective Hamiltonians of these theories and average Hamiltonian theory are presented. PMID:24034855

  10. Applications of Floquet-Magnus expansion, average Hamiltonian theory and Fer expansion to study interactions in solid state NMR when irradiated with the magic-echo sequence.

    PubMed

    Mananga, Eugene Stephane

    2013-01-01

    This work presents the possibility of applying the Floquet-Magnus expansion and the Fer expansion approaches to the most useful interactions known in solid-state nuclear magnetic resonance using the magic-echo scheme. The results of the effective Hamiltonians of these theories and average Hamiltonian theory are presented.

  11. [On the quest for the right way--life and work of Magnus Schmid (1918-1977), historian of medicine].

    PubMed

    Mildenberger, Florian

    2008-01-01

    Magnus Schmid seems to have been an "ordinary historian of medicine" from 1950 to 1977 in Munich and Erlangen. Following his death he became forgotten by his colleagues. But despite the fact, that he did not publish great books, he modernized the subject and was open to new interpretations of history of medicine and to intercultural views on history. For more than 20 years he seemed to be a quite liberal researcher, but following the changes in society after the 1968/69 revolt, he became a fighter for a new conservatism. Schmid was unwilling to accept that people decided freely about their body and health, without consulting doctors like him while he believed in an unchangeable foundation of ethics in medicine (e. g. abortion). So Schmid, in the last years of his life to the fact, made his valuable scientific works disappear behind his dubious campaigning against the modernized western German society.

  12. Distinct effect of orphanin FQ in nucleus raphe magnus and nucleus reticularis gigantocellularis on the rat tail flick reflex.

    PubMed

    Yang, Z; Zhang, Y; Wu, G

    2001-06-22

    The aim of the present study is to investigate the effects of orphanin FQ (OFQ) microinjected into the nucleus raphe magnus (NRM) and the nucleus reticularis gigantocellularis (NGC) on pain modulation. The tail-flick latency (TFL) was used as a behavioral index of nociceptive responsiveness. The result showed microinjection of OFQ into the NRM significantly increased the TFL, whereas microinjection of OFQ into the NGC decreased the TFL, suggesting the analgesic effect of OFQ in the NRM and the hyperalgesic effect of OFQ in the NGC. As there are three classes of putative pain modulating neurons in the rostral ventromedial medulla (RVM), the hyperalgesic or analgesic effect of OFQ in the RVM might depend upon the different class of the neurons being acted.

  13. Progress in spin dynamics solid-state nuclear magnetic resonance with the application of Floquet-Magnus expansion to chemical shift anisotropy.

    PubMed

    Mananga, Eugene Stephane

    2013-01-01

    The purpose of this article is to present an historical overview of theoretical approaches used for describing spin dynamics under static or rotating experiments in solid state nuclear magnetic resonance. The article gives a brief historical overview for major theories in nuclear magnetic resonance and the promising theories. We present the first application of Floquet-Magnus expansion to chemical shift anisotropy when irradiated by BABA pulse sequence.

  14. Progress in Spin Dynamics Solid-State Nuclear Magnetic Resonance with the Application of Floquet-Magnus Expansion to Chemical Shift Anisotropy

    PubMed Central

    Mananga, Eugene Stephane

    2013-01-01

    The purpose of this article is to present an historical overview of theoretical approaches used for describing spin dynamics under static or rotating experiments in solid state nuclear magnetic resonance. The article gives a brief historical overview for major theories in nuclear magnetic resonance and the promising theories. We present the first application of Floquet-Magnus expansion to chemical shift anisotropy when irradiated by BABA pulse sequence. PMID:23711337

  15. A remarkable new species of the magnus species-group of Cryptocellus (Arachnida, Ricinulei) from Ecuador, with observations on the taxonomy of the New World genera.

    PubMed

    Botero-Trujillo, Ricardo; Valdez-Mondragón, Alejandro

    2016-05-03

    A new ricinuleid species, Cryptocellus chimaera sp. nov., is described based on a male specimen from Northwest Ecuador (Esmeraldas, Reserva Ecológica Mache-Chindul, Estación Biológica Bilsa). This species is unique among all Cryptocellus in having very large longitudinal carapacial translucent areas together with a markedly incrassate femur of leg II. Representing only the second species of the order described from Ecuador, C. chimaera sp. nov. is assigned to the magnus species-group of Cryptocellus Westwood, 1874. Cryptocellus chimaera sp. nov. is remarkable, for its morphology resembles that of Cryptocellus magnus Ewing, 1929, especially with regard to the male copulatory apparatus, although both resemble Pseudocellus Platnick, 1980, due to the presence of diffuse longitudinal carapacial translucent areas. Along with the new species description, a comparative diagnosis and supplementary images are provided for C. magnus. Based on direct observations of some species belonging to the five species-groups of Cryptocellus, we discuss on the occurrence of different morphologies of carapacial translucent areas within the genus. We deem it important to continue the survey of morphological characters, especially within Cryptocellus, in order to increase our understanding of the species-groups and to unravel their relationships.

  16. Role of the red nucleus in suppressing the jaw-opening reflex following stimulation of the raphe magnus nucleus.

    PubMed

    Satoh, Yoshihide; Ishizuka, Ken'Ichi; Iwasaki, Shin-ichi

    2014-08-01

    In a previous study, we found that electrical and chemical stimulation of the red nucleus (RN) suppressed the high-threshold afferent-evoked jaw-opening reflex (JOR). It has been reported that the RN receives bilaterally projection fibers from the raphe magnus nucleus (RMg), and that stimulation of the RMg inhibits the tooth pulp-evoked nociceptive JOR. These facts imply that RMg-induced inhibition of the JOR could be mediated via the RN. The present study first examines whether stimulation of the RMg suppresses the high-threshold afferent-evoked JOR. The JOR was evoked by electrical stimulation of the inferior alveolar nerve (IAN), and was recorded as the electromyographic response of the anterior belly of the digastric muscle. The stimulus intensity was 4.0 (high-threshold) times the threshold. Conditioning electrical stimulation of the RMg significantly suppressed the JOR. A further study then examined whether electrically induced lesions of the RN or microinjection of muscimol into the RN affects RMg-induced suppression of the JOR. Electrically induced lesions of the bilateral RN and microinjection of muscimol into the bilateral RN both reduced the RMg-induced suppression of the JOR. These results suggest that RMg-induced suppression of the high-threshold afferent-evoked JOR is mediated by a relay in the RN.

  17. On the nameless love and infinite sexualities: John Henry Mackay, Magnus Hirschfeld and the origins of the sexual emancipation movement.

    PubMed

    Bauer, J Edgar

    2005-01-01

    Two prominent representatives of the sexual emancipation movement in Germany, John Henry Mackay (1864-1933) and Magnus Hirschfeld (1868-1935) launched significant attacks on sexual binarism and its combinatories. Although Mackay defended the nameless love against seminal Christian and subsequent secularised misconstructions of its nature, he was unable to overcome the fundamental scheme of binomic sexuality. Hirschfeld, however, resolved the theoretical issue through his doctrine of sexual intermediaries (Zwischenstufenlehre) which purports that-without exception- all human beings are intersexual variants, i.e. unique composites of different proportions of masculinity and femininity. Since these proportions vary from one sexual layer of description to another in the same individual and can alter or be altered in time, it is sensu stricto not possible implies a radical deconstruction of not only binomic sexuality but its supplementation through a third sex. It offers a meta-theoretical framework for rethinking sexual difference beyond the fictional schemes and categorial closures of Western traditions of sexual identity. His assumption of potentially infinite sexualities anticipates some of the basic tenets forwarded by the philosophical and political agendas of queer studies. to postulate discrete sexual categories. Hirschfeld's doctrine.

  18. Antinociceptive role of oxytocin in the nucleus raphe magnus of rats, an involvement of mu-opioid receptor.

    PubMed

    Wang, Jing-Wen; Lundeberg, Thomas; Yu, Long-Chuan

    2003-10-15

    Recent studies showed that oxytocin plays an important role in nociceptive modulation in the central nervous system. The present study was undertaken to investigate the role of oxytocin in antinociception in the nucleus raphe magnus (NRM) of rats and the possible interaction between oxytocin and the opioid systems. Intra-NRM injection of oxytocin induced dose-dependent increases in hindpaw withdrawal latencies (HWLs) to noxious thermal and mechanical stimulation in rats. The antinociceptive effect of oxytocin was significantly attenuated by subsequent intra-NRM injection of the oxytocin antagonist 1-deamino-2-D-Tyr-(Oet)-4-Thr-8-Orn-oxytocin. Intra-NRM injection of naloxone dose-dependently antagonized the increased HWLs induced by preceding intra-NRM injection of oxytocin, indicating an involvement of opioid receptors in oxytocin-induced antinociception in the NRM of rats. Furthermore, the antinociceptive effect of oxytocin was dose-dependently attenuated by subsequent intra-NRM injection of the mu-opioid antagonist beta-funaltrexamine (beta-FNA), but not by the kappa-opioid antagonist nor-binaltorphimine (nor-BNI) or the delta-opioid antagonist naltrindole. The results demonstrated that oxytocin plays an antinociceptive role in the NRM of rats through activating the oxytocin receptor. Moreover, mu-opioid receptors, not kappa and delta receptors, are involved in the oxytocin-induced antinociception in the NRM of rats.

  19. Role of opioidergic and GABAergic neurotransmission of the nucleus raphe magnus in the modulation of tonic immobility in guinea pigs.

    PubMed

    da Silva, Luis Felipe Souza; Menescal-de-Oliveira, Leda

    2007-04-02

    Tonic immobility (TI) is an inborn defensive behavior characterized by a temporary state of profound and reversible motor inhibition elicited by some forms of physical restraint. Previous results from our laboratory have demonstrated that nucleus raphe magnus (NRM) is also a structure involved in the modulation of TI behavior, as chemical stimulation through carbachol decreases the duration of TI in guinea pigs. In view of the fact that GABAergic and opioidergic circuits participate in the regulation of neuronal activity in the NRM and since these neurotransmitters are also involved in the modulation of TI, the objective of the present study was to evaluate the role of these circuits of the NRM in the modulation of the behavioral TI response. Microinjection of morphine (4.4 nmol/0.2 microl) or bicuculline (0.4 nmol/0.2 microl) into the NRM increased the duration of TI episodes while muscimol (0.5 nmol/0.2 microl) decreased it. The effect of morphine injection into the NRM was blocked by previous microinjection of naloxone (2.7 nmol/0.2 microl). Muscimol at 0.25 nmol did not produce any change in TI duration; however, it blocked the increased response induced by morphine. Our results indicate a facilitatory role of opioidergic neurotransmission in the modulation of the TI response within the NRM, whereas GABAergic activity plays an inhibitory role. In addition, in the present study the modulation of TI in the NRM possibly occurred via an interaction between opioidergic and GABAergic systems, where the opioidergic effect might be due to inhibition of tonically active GABAergic interneurons.

  20. Total syntheses of (±)-spiroindimicins B and C enabled by a late-stage Schöllkopf-Magnus-Barton-Zard (SMBZ) reaction.

    PubMed

    Blair, Lachlan M; Sperry, Jonathan

    2016-01-14

    The spiroindimicins are a family of structurally unprecedented alkaloids isolated from the deep-sea-derived marine actinomycete Streptomyces sp. SCSIO 03032. The total syntheses of (±)-spiroindimicins B and C are disclosed, the first of any member of this family. Central to the successful strategy was installing the spirocentre using a mild intramolecular Heck reaction, the assembly of a pentacyclic spirobisindole by Fischer indolization and a late-stage Schöllkopf-Magnus-Barton-Zard (SMBZ) reaction to construct the trisubstituted pyrrole.

  1. Mercury and sulphur among the High Medieval alchemists: from Rāzī and Avicenna to Albertus Magnus and pseudo-Roger Bacon.

    PubMed

    Newman, William R

    2014-11-01

    This essay challenges the often expressed view that the principles of metals, namely mercury and sulphur, were generally viewed by alchemists as being of a 'metaphysical' character that made them inaccessible to the tools and operations of the laboratory. By examining a number of Arabo-Latin and Latin alchemical texts in circulation before the end of the thirteenth century, the author presents evidence that most alchemists of the period considered mercury and sulphur to be materials subject to techniques of purification in the same way that naturally occurring salts and minerals could be freed of their impurities or dross. The article also points to the immense influence of Avicenna and Albertus Magnus in formulating the theory that mercury and sulphur were compounds of different materials, containing both fixed and unfixed components. Finally, the author briefly examines the relationship between this materialist approach to the principles and the chymical atomism of early modern authors who were deeply aware of medieval alchemical literature.

  2. Efficient theory of dipolar recoupling in solid-state nuclear magnetic resonance of rotating solids using Floquet-Magnus expansion: application on BABA and C7 radiofrequency pulse sequences.

    PubMed

    Mananga, Eugene S; Reid, Alicia E; Charpentier, Thibault

    2012-02-01

    This article describes the use of an alternative expansion scheme called Floquet-Magnus expansion (FME) to study the dynamics of spin system in solid-state NMR. The main tool used to describe the effect of time-dependent interactions in NMR is the average Hamiltonian theory (AHT). However, some NMR experiments, such as sample rotation and pulse crafting, seem to be more conveniently described using the Floquet theory (FT). Here, we present the first report highlighting the basics of the Floquet-Magnus expansion (FME) scheme and hint at its application on recoupling sequences that excite more efficiently double-quantum coherences, namely BABA and C7 radiofrequency pulse sequences. The use of Λ(n)(t) functions available only in the FME scheme, allows the comparison of the efficiency of BABA and C7 sequences.

  3. Anti-nociceptive effects of calcitonin gene-related peptide in nucleus raphe magnus of rats: an effect attenuated by naloxone.

    PubMed

    Huang, Y; Brodda-Jansen, G; Lundeberg, T; Yu, L C

    2000-08-04

    The present study investigated the role of calcitonin gene-related peptide (CGRP) on nociception in nucleus raphe magnus (NRM) and the interaction between CGRP and opioid peptides in NRM of rats. CGRP-like immunoreactivity was found at a concentration of 6.0+/-0. 77 pmol/g in NRM tissue of ten samples of rats, suggesting that it may contribute to physiological responses orchestrated by the NRM. The hindpaw withdrawal latency (HWL) to thermal and mechanical stimulation increased significantly after intra-NRM administration of 0.5 or 1 nmol of CGRP in rats, but not 0.25 nmol. The anti-nociceptive effect induced by CGRP was antagonized by following intra-NRM injection of 1 nmol of the CGRP receptor antagonist CGRP8-37. Furthermore, the CGRP-induced anti-nociceptive effect was attenuated by following intra-NRM administration of 6 nmol of naloxone. The results indicate that CGRP and its receptors play an important role in anti-nociception, and there is a possible interaction between CGRP and opioid peptides in NRM of rats.

  4. Effects of electroacupuncture on orphanin FQ immunoreactivity and preproorphanin FQ mRNA in nucleus of raphe magnus in the neuropathic pain rats.

    PubMed

    Ma, Fei; Xie, Hong; Dong, Zhi-Qiang; Wang, Yan-Qing; Wu, Gen-Cheng

    2004-07-15

    Orphanin FQ (OFQ) is an endogenous ligand for opioid receptor-like-1 (ORL1) receptor. Previous studies have shown that both OFQ immunoreactivity and preproorphanin FQ (ppOFQ) mRNA expression could be observed in the brain regions involved in pain modulation, e.g., nucleus of raphe magnus (NRM), dorsal raphe nucleus (DRN), and ventrolateral periaqueductal gray (vlPAG). It was reported that electroacupuncture (EA) has analgesic effect on neuropathic pain, and the analgesic effect was mediated by the endogenous opioid peptides. In the present study, we investigated the effects of EA on the changes of OFQ in the neuropathic pain rats. In the sciatic nerve chronic constriction injury (CCI) model, we investigated the changes of ppOFQ mRNA and OFQ immunoreactivity in NRM after EA by in situ hybridization (ISH) and immunohistochemistry methods, respectively. Then, the ppOFQ mRNA-positive and OFQ immunoreactive cells were counted under a computerized image analysis system. The results showed that expression of ppOFQ mRNA decreased and OFQ immunoreactivity increased after EA treatment in the neuropathic pain rats. These results indicated that EA modulated OFQ synthesis and OFQ peptide level in NRM of the neuropathic pain rats.

  5. TMJ inflammation increases Fos expression in the nucleus raphe magnus induced by subsequent formalin injection of the masseter or hindpaw of rats.

    PubMed

    Oh, Sang-Hoon; Imbe, Hiroki; Iwai-Liao, Yasutomo

    2006-08-01

    The study was designed to examine the effect of persistent temporomandibular joint (TMJ) inflammation on neuronal activation in the descending pain modulatory system in response to noxious stimulus. Formalin was injected into the left masseter muscle or hindpaw of rats 10 days after injection of the left TMJ with saline or complete Freund's adjuvant (CFA). The results showed that 10-day persistent TMJ inflammation (induced by CFA) alone did not induce a significant increase in Fos-like immunoreactive (Fos-LI) neurons in the rostral ventromedial medulla (RVM) or locus coeruleus (LC), but that formalin injection of the masseter muscle or hindpaw induced a significant increase in Fos-LI neurons in the RVM and LC of rats with and without TMJ inflammation (P < 0.05). However, persistent TMJ inflammation significantly increased Fos-LI neurons in the nucleus raphe magnus (NRM) induced by subsequent formalin injection of the masseter muscle and hindpaw (70.2% increase and 53.8% increase, respectively, over the control TMJ-saline-injected rats; P < 0.05). The results suggest that persistent TMJ inflammation increases neuronal activity, in particularly in the NRM, by the plastic change of the descending pain modulatory system after ipsilateral application of a noxious stimulus to either orofacial area or a spatially remote body area.

  6. Role of glutamatergic receptors located in the nucleus raphe magnus on antinociceptive effect of morphine microinjected into the nucleus cuneiformis of rat.

    PubMed

    Haghparast, Abbas; Soltani-Hekmat, Ava; Khani, Abbas; Komaki, Alireza

    2007-10-29

    Neurons in the nucleus cuneiformis (CnF), located just ventrolateral to the periaqueductal gray, project to medullary nucleus raphe magnus (NRM), which is a key medullary relay for descending pain modulation and is critically involved in opioid-induced analgesia. Previous studies have shown that antinociceptive response of CnF-microinjected morphine can be modulated by the specific subtypes of glutamatergic receptors within the CnF. In this study, we evaluated the role of NMDA and kainate/AMPA receptors that are widely distributed within the NRM on morphine-induced antinociception elicited from the CnF. Hundred and five male Wistar rats weighing 250-300 g were used. Morphine (10, 20 and 40 microg) and NMDA receptor antagonist, MK-801 (10 microg) or kainate/AMPA receptor antagonist, DNQX (0.5 microg) in 0.5 microl saline were stereotaxically microinjected into the CnF and NRM, respectively. The latency of tail-flick response was measured at set intervals (2, 7, 12, 17, 22, 27 min after microinjection) by using an automated tail-flick analgesiometer. The results showed that morphine microinjection into the CnF dose-dependently causes increase in tail-flick latency (TFL). MK-801 microinjected into the NRM, just 1 min before morphine injection into the CnF, significantly attenuated antinociceptive effects of morphine. On the other hand, DNQX microinjected into the NRM, significantly increased TFL after local application of morphine into the CnF. We suggest that morphine related antinociceptive effect elicited from the CnF is mediated, in part, by NMDA receptor at the level of the NRM whereas kainite/AMPA receptor has a net inhibitory influence at the same pathway.

  7. Electrolytic lesion of the nucleus raphe magnus reduced the antinociceptive effects of bilateral morphine microinjected into the nucleus cuneiformis in rats.

    PubMed

    Haghparast, Abbas; Ordikhani-Seyedlar, Mehdi; Ziaei, Maryam

    2008-06-27

    Several lines of investigation show that the rostral ventromedial medulla is a critical relay for midbrain regions, including the nucleus cuneiformis (CnF), which control nociception at the spinal cord. There is some evidence that local stimulation or morphine administration into the CnF produces the effective analgesia through the nucleus raphe magnus (NRM). The present study tries to determine the effect of morphine-induced analgesia following microinjection into the CnF in the absence of NRM. Seven days after the cannulae implantation, morphine was microinjected bilaterally into the CnF at the doses of 0.25, 1, 2.5, 5, 7.5 and 10 microg/0.3 microl saline per side. The morphine-induced antinociceptive effect measured by tail-flick test at 30, 60, 90 and 120 min after microinjection. The results showed that bilateral microinjection of morphine into the CnF dose-dependently causes increase in tail-flick latency (TFL). The 50% effective dose of morphine was determined and microinjected into the CnF (2.5 microg/0.3 microl saline per side) in rats after NRM electrolytic lesion (1 mA, 30 s). Lesion of the NRM significantly decreased TFLs, 30 (P<0.01) and 60 (P<0.05) but not 90-120 min after morphine microinjection into the CnF, compared with sham-lesion group. We concluded that morphine induces the analgesic effects through the opioid receptors in the CnF. It is also appeared that morphine-induced antinociception decreases following the NRM lesion but it seems that there are some other descending pain modulatory pathways that activate in the absence of NRM.

  8. Antinociception induced by intravenous dipyrone (metamizol) upon dorsal horn neurons: involvement of endogenous opioids at the periaqueductal gray matter, the nucleus raphe magnus, and the spinal cord in rats.

    PubMed

    Vazquez, Enrique; Hernandez, Norma; Escobar, William; Vanegas, Horacio

    2005-06-28

    Microinjection of dipyrone (metamizol) into the periaqueductal gray matter (PAG) in rats causes antinociception. This is mediated by endogenous opioidergic circuits located in the PAG itself, in the nucleus raphe magnus and adjacent structures, and in the spinal cord. The clinical relevance of these findings, however, is unclear. Therefore, in the present study, dipyrone was administered intravenously, and the involvement of endogenous opioidergic circuits in the so-induced antinociception was investigated. In rats, responses of dorsal spinal wide-dynamic range neurons to mechanical noxious stimulation of a hindpaw were strongly inhibited by intravenous dipyrone (200 mg/kg). This effect was abolished by microinjection of naloxone (0.5 microg/0.5 microl) into the ventrolateral and lateral PAG or into the nucleus raphe magnus or by direct application of naloxone (50 microg/50 microl) onto the spinal cord surface above the recorded neuron. These results show that dipyrone, a non-opioid analgesic with widespread use in Europe and Latin America, when administered in a clinically relevant fashion causes antinociception by activating endogenous opioidergic circuits along the descending pain control system.

  9. Physiological characteristics of the projection pathway from the medial preoptic to the nucleus raphe magnus of the rat and its modulation by the periaqueductal gray.

    PubMed

    Jiang, M; Behbehani, M M

    2001-11-01

    Anatomical studies have shown a strong projection from the medial preoptic nucleus of the hypothalamus (MPO) to both the periaqueductal gray (PAG) and nucleus raphe magnus (NRM). In this study, we examined the physiological characteristics of MPO to NRM connections and examined how blockade of neuronal transmission and of the glutamatergic system within the PAG modifies this pathway. In deeply anesthetized rats, recordings were made from NRM neurons that were identified by their response to peripheral mechanical stimulation and designated as "E", "I", or "N" if they were excited, inhibited, or not activated by noxious stimulation. In addition, cells were identified as spinally projecting if they could be antidromically activated by stimulation of the dorsolateral funiculus at the thoracic level. The responses of 204 NRM neurons to electrical and 87 cells to both chemical and electrical stimulation of MPO were recorded. The response of NRM neurons to MPO stimulation was highly dependent on the sensory class of these cells. Chemical stimulation of MPO inhibited 50% (16/32) and excited 16% (5/32) of the I-cells. In contrast, 23% (9/39) of the E-cells were inhibited and 49% (19/39) were excited by chemical stimulation of MPO. Electrical stimulation at intensities below 80 microA at 100Hz had similar effects on the two classes of cells; 62% (24/39) of the E-cells and 31% (10/32) of the I cells were excited, and 31% (12/39) of the E-cells and 59% (19/32) of the I-cells were inhibited. The excitatory response to chemical stimulation lasted for an average of 136.8+/-73.2s and inhibitory response lasted for an average of 143.8+/-102.1s. Electrical stimulation of MPO at 1Hz excited 27%, inhibited 3%, and had no effect on 70% of NRM cells. The mean latency to peak excitation was 9.6+/-6.6ms. Antidromic activation of MPO neurons by NRM stimulation showed an average latency of 6.3+/-3.4ms. Blocking the glutamatergic transmission within the PAG (by injecting kynurenic acid (KYN

  10. Magnus and Iordanskii Forces in Superfluids

    SciTech Connect

    Wexler, C.

    1997-08-01

    The transverse force acting on a quantized vortex in a superfluid is a problem that has eluded a complete understanding for more than three decades. In this Letter I calculate the {ital superfluid } velocity part of the transverse force in a way closely related to Laughlin{close_quote}s argument for the quantization of conductance in the quantum Hall effect. A combination of this result, the {ital vortex} velocity part of the transverse force found by Thouless, Ao, and Niu [Phys.Rev.Lett.{bold 76}, 3758 (1996)], and Galilean invariance shows that there cannot be a transverse force proportional to the normal fluid velocity. {copyright} {ital 1997} {ital The American Physical Society}

  11. 5-Hydroxytryptamine2A/2C receptors of nucleus raphe magnus and gigantocellularis/paragigantocellularis pars α reticular nuclei modulate the unconditioned fear-induced antinociception evoked by electrical stimulation of deep layers of the superior colliculus and dorsal periaqueductal grey matter.

    PubMed

    de Oliveira, Ricardo; de Oliveira, Rithiele Cristina; Falconi-Sobrinho, Luiz Luciano; da Silva Soares, Raimundo; Coimbra, Norberto Cysne

    2017-01-01

    The electrical stimulation of the dorsolateral columns of the periaquedutal grey matter (dlPAG) or deep layers of the superior colliculus (dlSC) evokes defensive behaviours followed by an antinociceptive response. Monoaminergic brainstem reticular nuclei are suggested to comprise the endogenous pain modulatory system. The aim of the present work was to investigate the role played by 5-HT2 subfamily of serotonergic receptors of the nucleus raphe magnus (NRM) and the gigantocellularis/paragigantocellularis pars α reticular nuclei (Gi/PGiα) in the elaboration of instinctive fear-induced antinociception elicited by electrical stimulation of dlPAG or of dlSC. The nociceptive thresholds were measured by the tail-flick test in Wistar rats. The 5-HT2A/2C-serotonergic receptors antagonist ritanserin was microinjected at different concentrations (0.05, 0.5 and 5.0μg/0.2μL) either in Gi/PGiα or in NRM. The blockade of 5-HT2 receptors in both Gi/PGiα and NRM decreased the innate fear-induced antinociception elicited by electrical stimulation of the dlSC or the dlPAG. These findings indicate that serotonin is involved in the hypo-algesia induced by unconditioned fear-induced behavioural responses and the 5-HT2A/2C-serotonergic receptor subfamily in neurons situated in the Gi/PGiα complex and NRM are critically recruited in pain modulation during the panic-like emotional behaviour.

  12. [The Tractatus de austuribus and its adoption by Albertus Magnus].

    PubMed

    Giese, Martina

    2009-01-01

    Probably in the 60s of the 13th century Albert the Great (dagger 1280) terminated his De animalibus libri XXVI, mainly a commentary on Aristotle's Animals but a milestone in medieval zoology. In the extensive chapter De falconibus of the 23rd book, which was written around 1250 and is probably the oldest part of the whole treatise, Albert used medieval tracts on birds of prey as source material. In the article one of these tracts, the anonymous Tractatus de austuribus on the healing of hawks, is analysed and for the first time presented in a critical synoptic edition (after the Codex unicus Bethesda [MD, USA], National Library of Medicine, 73, fol. 1ra-8ra) together with the insert in Albert's De animalibus and the modern German translation of Johann Erhard Pacius (1715-1796). Pacius' German translation of De falconibus was printed as an appendix together with his translation of Frederick's II famous De arte venandi cum avibus in the year 1756. It was partly based on the German translation of book 22-26 of De animalibus published by Walther Ryff in Frankfurt/M. in 1545.

  13. One-dimensional Magnus-type platinum double salts

    PubMed Central

    Hendon, Christopher H.; Walsh, Aron; Akiyama, Norinobu; Konno, Yosuke; Kajiwara, Takashi; Ito, Tasuku; Kitagawa, Hiroshi; Sakai, Ken

    2016-01-01

    Interest in platinum-chain complexes arose from their unusual oxidation states and physical properties. Despite their compositional diversity, isolation of crystalline chains has remained challenging. Here we report a simple crystallization technique that yields a series of dimer-based 1D platinum chains. The colour of the Pt2+ compounds can be switched between yellow, orange and blue. Spontaneous oxidation in air is used to form black Pt2.33+ needles. The loss of one electron per double salt results in a metallic state, as supported by quantum chemical calculations, and displays conductivity of 11 S cm−1 at room temperature. This behaviour may open up a new avenue for controllable platinum chemistry. PMID:27320502

  14. How Magnus Bends the Flying Ball - Experimenting and Modeling

    NASA Astrophysics Data System (ADS)

    Timková, V.; Ješková, Z.

    2017-02-01

    Students are well aware of the effect of the deflection of sports balls when they have been given a spin. A volleyball, tennis, or table tennis ball served with topspin results in an additional downward force that makes the ball difficult to catch and return. In soccer, the effect of sidespin causes the ball to curve unexpectedly sideways, resulting in a so-called banana kick that can confuse the goalkeeper. These surprising effects attract students' attention such that the motion of sports balls can be used to capture the interest of students towards the physics behind it. However, to study and analyze the motion of a real ball kicked in a playfield is not an easy task. Instead of the large-scale full-size sports ball motion, there can be designed and studied simpler experiments that can be carried out in the classroom. Moreover, digital technologies that are available at schools enable students to collect data from the experiment easily in a reasonable time. The mathematical model based on the analysis of forces acting on the ball flying in the air can be used to simulate the motion in order to understand the basic physical principles of the motion so that the best correspondence may be found.

  15. Improved Magnus` form approximation of saturation vapor pressure

    SciTech Connect

    Alduchov, O.A.; Eskridge, R.E.

    1997-11-01

    Relative humidity is usually measured in aerological observations and dew point depression is usually reported in upper-air reports. These variables must frequently be converted to other moisture variables in meteorological analysis. If relative humidity is converted to vapor pressure, most humidity variables can then be determined. Elliott and Gaffen reviewed the practices and procedures of the US radiosonde system. In their paper, a comparison of the relative errors was made between the saturation vapor pressure formulations of Tetens (1930), Goff-Gratch (1946), Wexler (1976), and Buck (1981). In this paper, the authors will expand the analysis of Elliott and Gaffen by deriving several new saturation vapor pressure formulas, and reviewing the various errors in these formulations. They will show that two of the new formulations of vapor pressure over water and ice are superior to existing formulas. Upper air temperature data are found to vary from about +50 C to {minus}80 C. This large variation requires a saturation vapor pressure equation to be accurate over a large temperature range. While the errors introduced by the use of relatively inaccurate conversion equations are smaller than the errors due to the instruments, dewpoint coding errors, and dewpoint conversion algorithms (Elliott and Gaffen, 1993); they introduce additional systematic errors in humidity data. The most precise formulation of vapor pressure over a plane surface of water was given by Wexler (1976). The relative errors of Tetens` (1930) formula and one due to Buck (1981) (Buck`s equation is recommended in the Federal Meteorological Handbook No. 3, 1991) are shown. The relative errors in this table are the predicted value minus the Wexler value divided by the Wexler value.

  16. 75 FR 74128 - Manual on Uniform Traffic Control Devices (MUTCD) Compliance Dates

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-30

    ... INFORMATION CONTACT: For questions about the program discussed herein, contact Mr. Hari Kalla, MUTCD Team Leader, FHWA Office of Operations, (202) 366-5915, or via e-mail at hari.kalla@dot.gov . For...

  17. A case of Finegoldia magna (formerly Peptostreptococcus magnus) infection mimicking disseminated malignancy.

    PubMed

    Basu, Pallavi; Williams, Anwen; O'Brien, Matthew T; Brouns, Mattheus; Edwards, Paul

    2016-12-01

    A 44-year-old alcoholic (and therefore immunocompromised) hospital cleaner presented with general malaise, weight loss, and erythematous skin nodules. Computed tomography scanning revealed a neck mass invading the thyroid gland, pulmonary infiltrates, liver lesions, and deposits on the anterior abdominal wall, consistent with disseminated malignancy. However, tissue diagnosis showed a necro-inflammatory process with no evidence of malignancy. Microscopy and culture of samples failed to detect any infectious pathogen, but after an extended incubation period, Finegoldia magna was isolated. This case study illustrates the importance of tissue diagnosis in suspected disseminated malignancy and raises the risk of acquiring the rarer bacteria amongst hospital staff.

  18. Manos Hadjidakis: The Story of an Anarchic Youth and a "Magnus Eroticus"

    ERIC Educational Resources Information Center

    Miralis, Yiannis

    2004-01-01

    The name of Manos Hadjidakis is probably unknown to contemporary musicians and music educators. After all, the Greek composer achieved his international fame back in 1961 when he won an Oscar for his soundtrack of the movie, "Never on Sunday." Numerous other awards followed from England, Krance, Germany, and of course, Greece. After his…

  19. Estimating the magnus moment effect on stability of 30-mm boomed projectiles

    NASA Astrophysics Data System (ADS)

    Byers, R. H.; Cobb, K.

    1985-08-01

    This report documents the results obtained from a comparison of free-flight spark range tests and PRODASMAGNUS computer stability results for 30mm spin stabilized projectiles. Two configurations were considered, each with the same boom diameter of 0.5, 1.0 inch and 1.25 inch boom lengths. The results show that PRODASMAGNUS can accurately predict the effects of a boom's presence on projectile stability.

  20. Magnus Effect: An Overview of Its Past and Future Practical Applications. Volumes 1 and 2

    DTIC Science & Technology

    1986-01-01

    points of reversal and the 2.30ś,4181 1/1943 McDonaid ............................... 416/4 ueto of hr s cnbea Utd.-~ 2.753.006 7/1956 Franz ...42O 5]£0KL (56) Refereacm Cked oo m ofn ess zfi d UN3TED STATES PATEMT wings for ak-,hf and hydrofoil boa :, and rotary 3,S6.54 /171 Hsayr. 4440 b.adcs

  1. Response to Yiannis Miralis, "Manos Hadjidakis: The Story of an Anarchic Youth and a "Magnus Eroticus""

    ERIC Educational Resources Information Center

    Helfer, Jason

    2004-01-01

    There are two issues that struck the author, Jason Helfer, as essential from his consideration of Miralis' paper and the ideas of Manos Hadjidakis: Eros as a pedagogical idea and learner interactions in the music classroom. These ideas developed from his interpretation of Miralis' paper, from his experiences in teacher training, and teaching in…

  2. Albertus, "Magnus" or Magus? Magic, natural philosophy, and religious reform in the late middle ages.

    PubMed

    Collins, David J

    2010-01-01

    This article analyzes the fifteenth-century attempt by the Dominican order, especially in Cologne, to win canonization for the thirteenth-century natural philosopher Albert the Great. It shows how Albert's thought on natural philosophy and magic was understood and variously applied, how the Dominicans at Cologne composed his vitae, and how the order's Observant movement participated in these developments. It situates the canonization attempt at the intersection of two significant trends in which the order was a leading participant: first, the late medieval efforts to reform Christian society beginning with the religious life of monks and mendicants; second, the increasing concerns about the practice of learned and demonic mafic that laid groundwork for the witch-hunting of the early modern period. This article aims to shed light on intersections of science and religion -- their apprehension and negotiation -- at a decisive moment in European history for both fields of human endeavor.

  3. A Wind Tunnel Study of Magnus Effects on a Differentially Rotating Missile

    DTIC Science & Technology

    1992-12-01

    design ideas and knowledge of electronics enabled me to design the model. Finally, my thanks to my husband, Dan, for encouraging me and putting up with my...rA0 V~ E6 SL~L SQf (P IQ N C (M V (D C .5.a 0 0 0 6-26I (0 (E6 00 e 0- in fn7 CP ý IT 4 L0 0009 9909 V 6-27 Go L L Sc+ L& 4n. 6-28L LI I L L 6-28 0

  4. Effects of Small Nose Bluntness on Static Stability and Magnus Characteristics of a Projectile Shape at Mach 0.91 and 3.03.

    DTIC Science & Technology

    1986-07-01

    34 • - - ,-- - --’ - . - t,- . . .j, .;. ate .. J .- .. - -, - . L. ... - .L .. . . - . .. 2.. ! 4 I111IL2 1. 4 L:__ MICROCOPY RESOLUTION TESi CHART NATI(INAL PUR[AU OF...Stokes Computations are being used for transonic flowfields, including base flows. These computations can often be facilitated by the use of a sharp nose...106 at Mach 0.91 and 2.2 x 106 at Mach 3.02 based on the model length. Data for the static stability phase of the program was acquired by pitching

  5. Experimental Magnus and Static Stability Characteristics of Ballistic Projectiles with Various Boattail Angles and Lengths at Mach Numbers from 0.5 Through 2.5

    DTIC Science & Technology

    1975-08-01

    BOATTAIL ANGLES AND LENGTHS AT MACH NUMBERS FROM 0.5 THROUGH 2.5 I m m I PROPULSION WIND TUNNEL FACILITY ARNOLD ENGINEERING DEVELOPMENT CENTER AIR... Wind T u n n e l ( 4 T ) , P r o p u l s i o n Wind T u n n e l F a c i l i t y (PWT). The t e s t s w e r e p a r t o f a c o n t i n u i...with a variable stagnation pressure from 2.1 to 23.6 psia at all Mach numbers. The test section is 4 ft square and 12.5 ft long with variable ~orosity

  6. Magnus and Roll-Damping Characteristics of the Fixed-Fin and Inflatable Stabilizer Retarder Configurations of the MK-82 Store at Transonic Speeds

    DTIC Science & Technology

    1975-12-01

    model in the wind tunnel. D O -J 01 01 to Tachometer Clutch Turbiner Typical / Model Tachometer Ring Balance -Model Support Can Sting...TRANSONIC SPEEDS PROPULSION WIND TUNNEL FACILITY ARNOLD ENGINEERING DEVELOPMENT CENTER AIR FORCE SYSTEMS COMMAND ARNOLD AIR FORCE STATION...forward end of the sting. The turbine is used to spin the model to some’desired speed and then is disengaged with an air-operated sliding clutch to

  7. Interaction of ultrasound with vortices in type-II superconductors

    SciTech Connect

    Sonin, E.B.

    1996-04-01

    The theory of ultrasound in the mixed state of type-II superconductors is suggested which takes into account the Magnus force on vortices, the anti-Magnus force on ions, and diamagnetism of the mixed state. The acoustic Faraday effect (rotation of polarization of the transverse ultrasonic wave propagating along vortices) is linear in the Magnus force in any regime of the flux flow for wavelengths now used in the ultrasound experiments. Therefore, in contrast to previous predictions, the Faraday effect should be looked for only in clean superconductors with a strong Magnus force. {copyright} {ital 1996 The American Physical Society.}

  8. Transverse forces on a vortex in lattice models of superfluids

    NASA Astrophysics Data System (ADS)

    Sonin, E. B.

    2013-12-01

    The paper derives the transverse forces (the Magnus and the Lorentz forces) in the lattice models of superfluids in the continuous approximation. The continuous approximation restores translational invariance absent in the original lattice model, but the theory is not Galilean invariant. As a result, calculation of the two transverse forces on the vortex, Magnus force and Lorentz force, requires the analysis of two balances, for the true momentum of particles in the lattice (Magnus force) and for the quasimomentum (Lorentz force) known from the Bloch theory of particles in the periodic potential. While the developed theory yields the same Lorentz force, which was well known before, a new general expression for the Magnus force was obtained. The theory demonstrates how a small Magnus force emerges in the Josephson-junction array if the particle-hole symmetry is broken. The continuous approximation for the Bose-Hubbard model close to the superfluid-insulator transition was developed, which was used for calculation of the Magnus force. The theory shows that there is an area in the phase diagram for the Bose-Hubbard model, where the Magnus force has an inverse sign with respect to that which is expected from the sign of velocity circulation.

  9. On the non-linear vibrations of a projectile

    NASA Astrophysics Data System (ADS)

    Rath, P. C.; Sharma, S. M.

    1981-08-01

    The Nonlinear Magnus effect on the nutational oscillations of a missile has been studied. In particular the existence of self-sustained vibrations has been proved. A numerical method is suggested to obtain the limit cycles wherever they exist.

  10. Final Shuttle Crew Recaps Mission for Dryden Staff

    NASA Video Gallery

    STS-135 crew members, commander Chris Ferguson, pilot Doug Hurley and mission specialists Sandy Magnus and Rex Walheim, recalled personal highlights of the final shuttle mission and their involveme...

  11. Sir Paul McCartney Wake-up Song and Greeting

    NASA Video Gallery

    Paul McCartney and Beatles favorite "Good Day Sunshine" greet the Atlantis crew of Chris Ferguson, Doug Hurley, Sandy Magnus and Rex Walheim first thing on Flight Day 8. Sir Paul and the Beatles’...

  12. Stennis Space Center Wakes STS-135 Crew

    NASA Video Gallery

    The Flight Day 10 wakeup music was “Celebration” by Kool and the Gang, which was played for Mission Specialist Sandy Magnus. The song was accompanied by a special good morning message recorded ...

  13. 75 FR 33662 - Commercial Driver's License (CDL) Standards; Volvo Trucks North America, Inc.'s Exemption...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-14

    ... the requisite CDL issued by one of the States. Magnus Ericsson and Conny Harlin are part of a team of... of the exemption would be inconsistent with the goals and objectives of 49 U.S.C. 31315 and...

  14. An analytical treatment for three neutrino oscillations in the Earth

    NASA Astrophysics Data System (ADS)

    Aguilar-Arevalo, A. A.; D'Olivo, J. C.; Supanitsky, A. D.

    2012-08-01

    A simple, and at the same time accurate, description of the Earth matter effects on the oscillations between three neutrino flavors is given in terms of the Magnus expansion for the evolution operator.

  15. Effect of polarization on the trajectory of dissipative solitons

    NASA Astrophysics Data System (ADS)

    Sadykov, N. R.

    2009-01-01

    We show that the optical Magnus effect for dissipative solitons is determined not only by the helicity but also by the topological index, i.e., by the magnetic quantum number or by the projection of the soliton orbital moment on its trajectory. In the case of inhomogeneous media, we find a relation between the optical Magnus effect and the nonholonomy of the field of unit vectors tangent to the trajectory.

  16. Spin-Orbit Interaction of a Photon in AN Inhomogeneous Medium

    NASA Astrophysics Data System (ADS)

    Liberman, V. S.; Zel'Dovich, B. Ya.

    The following sections are included: * Introduction * Transverse Shift of the Circularly Polarized Beam (CPB) due to Refraction * Differential Equations for a Trajectory and Polarization of the Ray. Hamilton's Form of the Equations * Optical Magnus Effect in a Graded-Index Waveguide * Optical Ping-Pong Effect in a Step-Like Index Waveguide * Paraxial Approximation for Maxwell's Equations * Spin-Orbit Corrections to the Paraxial Approximation: Hermitian Interaction Hamiltonian * The Wave Description of the Optical Magnus Effect * Conclusion * Acknowledgement * References

  17. Coiled tubing solves multiple downhole problems

    SciTech Connect

    Bedford, S. ); Smith, I. )

    1994-11-01

    Declining reservoir pressure and water breakthrough in the UK North Sea Magnus field has coincided with general advances in application of coiled tubing and a continuous drive to reduce operating costs, particularly in a climate of weak oil prices. These factors have led to a dramatic increase in diversity and volume of coiled tubing interventions. In the following article, coiled tubing interventions, and results of those interventions, are discussed. An assessment of future coiled tubing activity on Magnus field is provided.

  18. The H-Function and Probability Density Functions of Certain Algebraic Combinations of Independent Random Variables with H-Function Probability Distribution

    DTIC Science & Technology

    1981-05-01

    functions and the H- function," Boletin do la Academia de Ciencias Fisicas Matematicas v Naturales (Caracas), 31, 95- 102 (1971). 120. Jain, U. C...Society, 37, 329- 334 (1973). 32. Oliver, M. L., and S. L. Kalla, "On the derivative of Fox’s H- function," (Spanish) Acta 14,dlcana de Ciencia -v...34 Universidade de Lisboa Revista de Faculdade de Ciencias FMatematicas, II, Series A, 13, 109-114 (1969-70). 92. Bajpai, S. D., "On some results involving Fox’s H

  19. Simulation of aeolian sand saltation with rotational motion

    NASA Astrophysics Data System (ADS)

    Huang, Ning; Wang, Cong; Pan, Xiying

    2010-11-01

    In this work, we propose a theoretical model based on the distribution functions of initial liftoff velocity and angular velocity of sand grains to describe a sand saltation process in which both wind field-sand grain coupling and the Magnus force experienced by saltating sand grains have been incorporated. The computation results showed that the Magnus force had significant effects on sand grain saltation. In particular, when the Magnus force was incorporated, the calculated sand transport fluxes and sand transport rate per unit width were closer to the experimental value than when this force was excluded. The sand transport flux is enhanced because the Magnus force owing to particle rotation causes the particles to have higher and longer trajectories, so the particles can get more speed and energy from the wind, which leads to a larger sand transport flux. In addition, it was found that when taking the Magnus force into account, the probability density of the impact velocity and angular velocity of saltating sand grains followed an exponential distribution and a unimodal asymmetric distribution, respectively. Moreover, the sand energy flux increased with the height above the sand surface until the energy flux reached its maximum and then decreased. Furthermore, the energy flux near the ground surface decreased as the grain diameter increased, but beyond a specific height the energy flux increased with the grain diameter. Finally, for the same sand grain diameter, the energy flux increased with the friction velocity.

  20. Vortices in superconducting films: Statistics and fractional quantum Hall effect

    SciTech Connect

    Dziarmaga, J.

    1996-03-01

    We present a derivation of the Berry phase picked up during exchange of parallel vortices. This derivation is based on the Bogolubov{endash}de Gennes formalism. The origin of the Magnus force is also critically reanalyzed. The Magnus force can be interpreted as an interaction with the effective magnetic field. The effective magnetic field may be even of the order 10{sup 6}{ital T}/A. We discuss a possibility of the fractional quantum Hall effect (FQHE) in vortex systems. As the real magnetic field is varied to drive changes in vortex density, the vortex density will prefer to stay at some quantized values. The mere existence of the FQHE does not depend on vortex quantum statistics, although the pattern of the plateaux does. We also discuss how the density of anyonic vortices can lower the effective strengh of the Magnus force, what might be observable in measurements of Hall resistivity. {copyright} {ital 1996 The American Physical Society.}

  1. STS-112 Post Flight Presentation

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The STS-112 post flight presentation begins with a shot of the moonrise over the Earth's Limb. A photograph of the STS-112 crew is shown. The crew consists of Mission Specialists Sandy Magnus, David Wolf, Piers Sellers and Fodor Yurchikhin, Pilot Pam Melroy and Commander Jeff Ashby. The crew departs from the Operations and Control Building to the launch pad at Kennedy Space Center in Florida. Sandy Magnus is shown preparing to board the Space Shuttle Atlantis. The actual STS-112 launch with flight deck activity during rendezvous with the International Space Station is also presented.

  2. STS-112 Flight Day 8 Highlights

    NASA Technical Reports Server (NTRS)

    2002-01-01

    On this eighth day of the STS-112 mission, the crew members of Atlantis (Commander Jeff Ashby; Pilot Pam Melroy; Mission Specialists Sandy Magnus, Piers Sellers, Dave Wolf, and Fyodor Yurchikhin) are seen preparing for the mission's third extravehicular activity (EVA). Magnus is shown reviewing instructions for operation of the International Space Station's (ISS) robot arm. Wolf and Sellers are seen successfully attaching cable connections to the S1 truss during the EVA. Scenes shown include: the ISS's robot arm, the Crew Equipment Translation Aid (CETA) cart and the deployment of the central radiator panel of the S1 truss.

  3. Effects of Base Cavity Depth on a Free Spinning Wrap-Around Fin Missile Configuration

    DTIC Science & Technology

    1995-12-01

    cases . One study which claimed advantageous force changes due to base cavities was the STRIX report (18). During the late 1980’s, Swedish Ordnance and...rotation, as seen from the rear, and the spin rate has no effect on this Magnus moment. In many cases this particular Magnus moment is much larger than the...and the sting/model aligned in the tunnel to read a near zero yaw moment. A zero reading was recorded, followed by a test run for the non- spinning case

  4. A new species of sesarmid crab of the genus Chiromantes (Crustacea: Decapoda: Brachyura) from the Ogasawara Islands, Japan.

    PubMed

    Komai, Tomoyuki; Ng, Peter K L

    2013-01-01

    A new species of sesarmid crab, Chiromantes magnus, is described from the Ogasawara (Bonin) Is., Japan. The new species was previously confused with C. dehaani (H. Milne Edwards, 1853). The different carapace shape, proportionally longer ambulatory legs, large adult size and the distinct live coloration distinguish the new species from its two closest congeners, C. dehaani and C. neglectus (De Man, 1887). Available information indicates that C. magnus n. sp. is endemic to the Ogasawara Is.; there is no evidence of the occurrence of the true C. dehaani in the Ogasawara Is.

  5. Interaction of vortex lattice with ultrasound and the acoustic Faraday effect

    SciTech Connect

    Dominguez, D.; Bulaevskii, L.; Ivlev, B.; Maley, M.; Bishop, A.R. |

    1995-03-27

    The interaction of sound with the vortex lattice is considered for high-{ital T}{sub {ital c}} superconductors, taking into account pinning and electrodynamic forces between vortices and crystal displacements. At low temperatures the Magnus force results in the acoustic Faraday effect; the velocity of sound propagating along the magnetic field depends on the polarization. This effect is linear in the Magnus force and magnetic field in crystals with equivalent {ital a} and {ital b} axes for a field parallel to the {ital c} axis. In the thermally activated flux flow regime, the Faraday effect is caused by electric and magnetic fields induced by vortices and acting on ions.

  6. Viscous flow over spinning cones at angle of attack.

    NASA Technical Reports Server (NTRS)

    Lin, T. C.; Rubin, S. G.

    1973-01-01

    A numerical finite-difference method is developed for evaluating the Magnus coefficients on spinning cones in laminar flow. The merged layer, the strong interaction region, and the downstream boundary layer are all considered. The numerical method is a predictor-corrector scheme developed for three-dimensional flows with or without crossflow diffusion. This method is particularly useful in problems in which a symmetry plane does not exist. Several contributions to the Magnus force and moments are considered. These include asymmetries in displacement thickness, centrifugal force and crossflow shear, and the effects of crossflow separation and vortex formation. Comparisons are made with experimental data and other analyses.

  7. Hypersonic Laminar Viscous Flow Past Spinning Cones at Angle of Attack

    NASA Technical Reports Server (NTRS)

    Agarwal, Ramesh; Rakich, John V.

    1982-01-01

    Computational results are presented for hypersonic viscous flow past spinning sharp and blunt cones of angle of attack, obtained with a parabolic Navier-Stokes marching code. The code takes into account the asymmetries in the flowfield resulting from spinning motion and computes the asymmetric shock shape, cross-flow and streamwise shear, heat transfer, cross-flow separation, and vortex structure. The Magnus force and moments are also computed. Comparisons are made with other theoretical analyses based on boundary-layer and boundary-region equations, and an anomaly is discovered in the displacement thickness contribution to the Magnus force when compared with boundary-layer results.

  8. Numerical simulation of steady supersonic flow over spinning bodies of revolution

    NASA Technical Reports Server (NTRS)

    Sturek, W. B.; Schiff, L. B.

    1982-01-01

    A recently reported parabolized Navier-Stokes code has been employed to compute the supersonic flowfield about a spinning cone and spinning and nonspinning ogive cylinder and boattailed bodies of revolution at moderate incidence. The computations were performed for flow conditions where extensive measurements for wall pressure, boundary-layer velocity profiles, and Magnus force had been obtained. Comparisons between the computational results and experiment indicate excellent agreement for angles of attack up to 6 deg. At angles greater than 6 deg discrepancies are noted which are tentatively attributed to turbulence modeling errors. The comparisons for Magnus effects show that the code accurately predicts the effects of body shape for the selected models.

  9. Efficient methods for linear Schrödinger equation in the semiclassical regime with time-dependent potential

    NASA Astrophysics Data System (ADS)

    Bader, Philipp; Iserles, Arieh; Kropielnicka, Karolina; Singh, Pranav

    2016-09-01

    We build efficient and unitary (hence stable) methods for the solution of the linear time-dependent Schrödinger equation with explicitly time-dependent potentials in a semiclassical regime. The Magnus-Zassenhaus schemes presented here are based on a combination of the Zassenhaus decomposition (Bader et al. 2014 Found. Comput. Math. 14, 689-720. (doi:10.1007/s10208-013-9182-8)) with the Magnus expansion of the time-dependent Hamiltonian. We conclude with numerical experiments.

  10. Joint Replacement Aircraft: The Case for a Single Multi-Mission HMLA Platform

    DTIC Science & Technology

    1999-01-01

    David S. Capt (USMC) The UH-1N Upgrade: At a Crossroads. Marine Corps Gazette, May 1996. 44-45. 41 Magnus, Robert. BGen (Asst. DCSA, USMC...51 Jane’s Land Based Air Defence. 228 52 Alexander, David R. Capt USA. Helicopter...53 Attenborough , Keith. Coupling Between Airborne Sound and the

  11. Postoperative Mediastinitis Due to Finegoldia magna with Negative Blood Cultures▿

    PubMed Central

    Kernéis, Solen; Matta, Matta; Hoï, Annie Buu; Podglajen, Isabelle; Gutmann, Laurent; Novara, Ana; Latremouille, Christian; Mainardi, Jean-Luc

    2009-01-01

    We report a case of Finegoldia magna (formerly known as Peptostreptococcus magnus) mediastinitis following coronary artery bypass in a 50-year-old patient. Even if staphylococci remain the main causative organism of postoperative mediastinitis, the responsibility of anaerobic bacteria must be considered in cases of fever and sternal drainage with negative blood cultures. PMID:19812272

  12. A Participants' DSS for a Management Game with a DSS Generator.

    ERIC Educational Resources Information Center

    Yeo, Gee Kin; Nah, Fui Hoon

    1992-01-01

    Describes the design of a decision support system (DSS) for a management game called MAGNUS (Management Game for National University of Singapore). Built-in models for performance analysis and decision making are explained; database query and model building are described; and future work is discussed. (11 references) (LRW)

  13. History as an Introduction to Science.

    ERIC Educational Resources Information Center

    Patterson, Elizabeth C.

    1980-01-01

    Discusses the controversy regarding the role of history of science in a liberal education, presenting two issues: What properly constitutes the subject and whether history of science has a place in the undergraduate curriculum. Describes a college course taught at Albertus Magnus College, New Haven, CT. (CS)

  14. Techniques Class: September 12, 2001.

    ERIC Educational Resources Information Center

    More, William; Corsetti, Patricia L.; Endleman, Orna; Julian, Sarah; Lindemann, Evie; Spinelli, Laura

    2002-01-01

    On September 12, 2001, the Techniques in Art Therapy class in the art therapy program at Albertus Magnus College met at its normal Wednesday evening time. This article describes the class session through the words and images of several class members who found the class useful in their own process of beginning to deal with the attacks and their…

  15. The Liberation Arts

    ERIC Educational Resources Information Center

    Pelikan, Jaroslav

    1973-01-01

    Text of a 1973 commencement address given at Albertus Magnus College concerning the goals of a liberal education (historical remembrance, critical reflection, moral resolve, and thoughtful reverence) that alone can truly liberate women and, through them, mankind as a whole. (Editor/PG)

  16. Squeezing the Calendar.

    ERIC Educational Resources Information Center

    Shea, Christopher

    1994-01-01

    Albertus Magnus College (Connecticut) has addressed the problem of declining enrollment offering a bachelor's degree program compressed into three years. Three full semesters are squeezed into an academic year. The semester is shortened by two weeks, but class time is lengthened. The third semester's tuition each year is discounted. (MSE)

  17. Heart and Reason: A Comparison of John Dewey's "A Common Faith" and His "Religious" Poems

    ERIC Educational Resources Information Center

    Miedema, Siebren

    2010-01-01

    In this article a comparison is drawn between the way in which the pragmatist philosopher and pedagogue John Dewey addressed religious issues and his view on Religious Education in his poetic narratives and in his scholarly writings, especially in his "magnus opus" on religion, "A Common Faith". Do we gain deeper insight into Dewey's view on…

  18. Post-Lie Algebras and Isospectral Flows

    NASA Astrophysics Data System (ADS)

    Ebrahimi-Fard, Kurusch; Lundervold, Alexander; Mencattini, Igor; Munthe-Kaas, Hans Z.

    2015-11-01

    In this paper we explore the Lie enveloping algebra of a post-Lie algebra derived from a classical R-matrix. An explicit exponential solution of the corresponding Lie bracket flow is presented. It is based on the solution of a post-Lie Magnus-type differential equation.

  19. BOOM: A Computer-Aided Engineering Tool for Exterior Ballistics of Smart Projectiles

    DTIC Science & Technology

    2011-06-01

    run on PC, Unix, or Mac systems. 15. SUBJECT TERMS projectiles, trajectory , aeroballistics, flight mechanics, smart projectiles 16. SECURITY...system model are provided. The procedure for running BOOM is also outlined, with input data files described in the appendices. Example trajectories ...in equation 9, the aerodynamic forces on the projectile are split into standard steady (SA) and Magnus (MA) terms as follows

  20. NCEL (Naval Civil Engineering Lab.) Ocean Platforms Seminar.

    DTIC Science & Technology

    1983-11-01

    type platforms. Both Cerveza and the Cerveza Ligera platforms[ 7] were launched in one piece and installed in 935 ft and 925 ft of water respectively...6. Magnus Jacket Takes Heavy Honors, Offshore V 42, No. 5, pp 189, 191- 193, May 1982. 7. Tannahill, C. A, W. M. Isenhower, D. D. Engle, Cerveza - A

  1. Vortex pair production and decay of a two-dimensional supercurrent by a quantum-field-theory approach

    NASA Astrophysics Data System (ADS)

    Iengo, Roberto; Jug, Giancarlo

    1995-09-01

    We investigate the phenomenon of the decay of a supercurrent through homogeneous nucleation of vortex-antivortex pairs in a two-dimensional (2D) like superconductor or superfluid by means of a quantum electrodynamic formulation for the decay of the 2D vacuum. The case in which both externally driven current and Magnus force are present is treated exactly, taking the vortex activation energy and its inertial mass as independent parameters. Quantum dissipation is included through the formulation introduced by Caldeira and Leggett. The most relevant consequence of quantum dissipation is the elimination of the threshold for vortex production due to the Magnus force. In the dissipation-dominated case, corresponding formally to the limit of zero intertial mass, an exact formula for the pair production rate is given. If however the inertial mass is strictly zero we find that vortex production is inhibited by a quantum effect related to the Magnus force. The possibility of including vortex pinning is investigated by means of an effective harmonic potential. While an additional term in the vortex activation energy can account for the effect of a finite barrier in the direction perpendicular to the current, pinning along the current depresses the role of the Magnus force in the dissipation-dominated dynamics, except for the above-mentioned quantum effect. A possible description of vortex nucleation due to the combined effects of temperature and externally driven currents is also presented along with an evaluation of the resulting voltage drop.

  2. The Bernoulli or Coanda Conundrum and Other Classical Demonstration Myths

    NASA Astrophysics Data System (ADS)

    Stille, Dale

    2009-11-01

    Lecture Demonstration professionals have recently taken a closer look at demonstrations that were traditionally labeled ``Bernoulli Demonstrations'' in most textbooks. This examination has shown that in most cases the Coanda Effect, Magnus Effect, and Entrainment may be better explanations for most of these classic demonstrations. A discussion of other similarly classic demonstrations and some of their problems or misconceptions will also be presented.

  3. Transverse forces on vortices in superfluids in a periodic potential

    NASA Astrophysics Data System (ADS)

    Sonin, E. B.

    2016-08-01

    The paper analyzes the transverse forces (the Magnus and the Lorentz forces) on vortices in superfluids put into periodic potentials at T =0 . The case of weak potential and the tight-binding limit described by the Bose-Hubbard model were addressed. The analysis was based on the balance of true momentum and quasimomentum. A special attention was paid to the superfluid close to the superfluid-insulator transition. In this area of the phase diagram the theory predicts the particle-hole symmetry line where the Magnus force changes sign with respect to that expected from the sign of velocity circulation. Our analysis has shown that the magnitude of the Magnus force is a continuous function at crossing the particle-hole symmetry line. This challenges the theory connecting the magnitude of the Magnus force with topological Chern numbers and predicting a jump at crossing this line. Disagreement is explained by the role of intrinsic pinning and guided vortex motion ignored in the topological approach. It is one more evidence that in general topological arguments are not sufficient for derivation of equations of vortex motion.

  4. [Astrologic and medical manuscript of the 18th Century].

    PubMed

    Kugener, Henri

    2010-01-01

    We present a manuscript from the 18th century, an extract taken from the "Great and the Little Albert" attributed to Albertus Magnus. The linguistic variety in the paper is typical for a text composed in Luxembourg. Added to this text are two incantations and a short cartomancy paper.

  5. Landing Day Wake Up Song and Greeting

    NASA Video Gallery

    Kate Smith’s rendition of Irving Berlin’s “God Bless America” woke Commander Chris Ferguson, Pilot Doug Hurley and Mission Specialists Sandy Magnus and Rex Walheim. But unlike most wakeup s...

  6. Registration of ‘Zenith' black bean

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘Zenith’ black bean (Phaseolus vulgaris L.) (Reg. no. CV- , PI -), developed by Michigan State University AgBioResearch was released in 2014 as an upright, full-season cultivar with anthracnose [caused by Colletotrichum lindemuthianum (Sacc. et Magnus) Lams.-Scrib] resistance and excellent canning q...

  7. Clausius-Clapeyron Equation and Saturation Vapour Pressure: Simple Theory Reconciled with Practice

    ERIC Educational Resources Information Center

    Koutsoyiannis, Demetris

    2012-01-01

    While the Clausius-Clapeyron equation is very important as it determines the saturation vapour pressure, in practice it is replaced by empirical, typically Magnus-type, equations which are more accurate. It is shown that the reduced accuracy reflects an inconsistent assumption that the latent heat of vaporization is constant. Not only is this…

  8. Finishing High School: Alternative Pathways and Dropout Recovery

    ERIC Educational Resources Information Center

    Tyler, John H.; Lofstrom, Magnus

    2009-01-01

    John Tyler and Magnus Lofstrom take a close look at the problems posed when students do not complete high school. The authors begin by discussing the ongoing, sometimes heated, debate over how prevalent the dropout problem is. They note that one important reason for discrepancies in reported dropout rates is whether holders of the General…

  9. Turbulence Modulation and Dense-Spray Structure

    DTIC Science & Technology

    1988-08-01

    experiments. Finally, Magnus and Saffman-lift forces and static pressure gradients can be ignored with little error (Faeth, 1977, 1983, 1988). Under...full-cone sprays. Recent Advances in Gas ] DInamics (C. Casci, ed.), Plenum Publishing Corporation, New York 78 Chehroudi, B., Onuma, Y., Chen, S.-H

  10. Chemical, Biochemical, and Genetic Approaches to Arsenic Metabolism" -An overview of arsenic metabolism and toxicity- A series of five papers to appear together in Current Protocols in Toxicology

    EPA Science Inventory

    The toxic properties of arsenic (As) were recognized long before Albertus Magnus in the 13th century prepared its elemental form (Buchanan, 1962). Its use as a poison has played lethal and decisive roles in domestic and dynastic intrigues throughout history (Cullen, 2008). Inorga...

  11. Overuse Injury Assessment Model

    DTIC Science & Technology

    2005-03-01

    et al. 1975)1 trabecular human Inelastic buckling 11.38 wet (Williams and Lewis 1982)1 trabecular human Back -calculating from finite element...superficialis Hip (Pelvis) Flexion Iliopsoas complex, rectus femoris, tensor fasciae latae, sartorius, pectineus Extension Semitendinosus, semimembranosus...digitorum superficialis Hip Flexion Iliopsoas complex, rectus femoris, tensor fasciae latae, sartorius, pectineus, adductor magnus, adductor longus

  12. Noncommuting Momenta of Topological Solitons

    NASA Astrophysics Data System (ADS)

    Watanabe, Haruki; Murayama, Hitoshi

    2014-05-01

    We show that momentum operators of a topological soliton may not commute among themselves when the soliton is associated with the second cohomology H2 of the target space. The commutation relation is proportional to the winding number, taking a constant value within each topological sector. The noncommutativity makes it impossible to specify the momentum of a topological soliton, and induces a Magnus force.

  13. Recent Experiments at the Gottingen Aerodynamic Institute

    NASA Technical Reports Server (NTRS)

    Ackeret, J

    1925-01-01

    This report presents the results of various experiments carried out at the Gottingen Aerodynamic Institute. These include: experiments with Joukowski wing profiles; experiments on an airplane model with a built-in motor and functioning propeller; and the rotating cylinder (Magnus Effect).

  14. Beckham as Physicist?

    ERIC Educational Resources Information Center

    Ireson, Gren

    2001-01-01

    If football captures the interest of students, it can be used to teach physics. In this case, a Beckham free-kick can be used to introduce concepts such as drag, the Bernoulli principle, Reynolds number, and the Magnus effect by asking the simple question: How does he curve the ball so much? Introduces basic mechanics along the way. (Author/ASK)

  15. Nonadiabatic three-neutrino oscillations in matter

    SciTech Connect

    DOlivo, J.C.; Oteo, J.A.

    1996-07-01

    Oscillations of three neutrinos in matter are analyzed by using the Magnus expansion for the time-evolution operator. We derive a simple expression for the electron-neutrino survival probability which is applied to the examination of the effect of a third neutrino on the nonadiabatic flavor transformations. {copyright} {ital 1996 The American Physical Society.}

  16. Direct numerical simulation of moderate-Reynolds-number flow past arrays of rotating spheres

    NASA Astrophysics Data System (ADS)

    Zhou, Qiang; Fan, Liang-Shih

    2015-07-01

    Direct numerical simulations with an immersed boundary-lattice Boltzmann method are used to investigate the effects of particle rotation on flows past random arrays of mono-disperse spheres at moderate particle Reynolds numbers. This study is an extension of a previous study of the authors [Q. Zhou and L.-S. Fan, "Direct numerical simulation of low-Reynolds-number flow past arrays of rotating spheres," J. Fluid Mech. 765, 396-423 (2015)] that explored the effects of particle rotation at low particle Reynolds numbers. The results of this study indicate that as the particle Reynolds number increases, the normalized Magnus lift force decreases rapidly when the particle Reynolds number is in the range lower than 50. For the particle Reynolds number greater than 50, the normalized Magnus lift force approaches a constant value that is invariant with solid volume fractions. The proportional dependence of the Magnus lift force on the rotational Reynolds number (based on the angular velocity and the diameter of the spheres) observed at low particle Reynolds numbers does not change in the present study, making the Magnus lift force another possible factor that can significantly affect the overall dynamics of fluid-particle flows other than the drag force. Moreover, it is found that both the normalized drag force and the normalized torque increase with the increase of the particle Reynolds number and the solid volume fraction. Finally, correlations for the drag force, the Magnus lift force, and the torque in random arrays of rotating spheres at arbitrary solids volume fractions, rotational Reynolds numbers, and particle Reynolds numbers are formulated.

  17. Flight dynamics of a spinning projectile descending on a parachute

    SciTech Connect

    Benedetti, G.A.

    1989-02-01

    During the past twenty years Sandia National Laboratories and the US Army have vertically gun launched numerous 155mm and eight-inch diameter flight test projectiles. These projectiles are subsequently recovered using an on-board parachute recovery system which is attached to the forward case structure of the projectile. There have been at least five attempts to describe, through analytical and numerical simulations, the translational and rotational motions of a spinning projectile descending on a parachute. However, none of these investigations have correctly described the large nutational motion of the projectile since all of them overlooked the fundamental mechanism which causes these angular motions. Numerical simulations as well as a closed form analytical solution show conclusively that the Magnus moment is responsible for the large nutational motion of the projectile. That is, when the center of pressure for the Magnus force is aft of the center of mass for the projectile, the Magnus moment causes an unstable (or large) nutational motion which always tends to turn the spinning projectile upside down while it is descending on the parachute. Conversely, when the center of mass for the projectile is aft of the center of pressure for the Magnus force, the Magnus moment stabilizes the nutational motion tending to always point the base of the spinning projectile down. The results of this work are utilized to render projectile parachute recovery systems more reliable and to explain what initially may appear to be strange gyrodynamic behavior of a spinning projectile descending on a parachute. 14 refs., 20 figs.

  18. Hamiltonian Engineering for High Fidelity Quantum Operations

    NASA Astrophysics Data System (ADS)

    Ribeiro, Hugo; Baksic, Alexandre; Clerk, Aashish

    High-fidelity gates and operations are crucial to almost every aspect of quantum information processing. In recent experiments, fidelity is mostly limited by unwanted couplings with states living out of the logical subspace. This results in both leakage and phase errors. Here, we present a general method to deal simultaneously with both these issues and improve the fidelity of quantum gates and operations. Our method is applicable to a wide variety of systems. As an example, we can correct gates for superconducting qubits, improve coherent state transfer between a single NV centre electronic spin and a single nitrogen nuclear spin, improve control over a nuclear spin ensemble, etc. Our method is intimately linked to the Magnus expansion. By modifying the Magnus expansion of an initially given Hamiltonian Hi, we find analytically additional control Hamiltonians Hctrl such that Hi +Hctrl leads to the desired gate while minimizing both leakage and phase errors.

  19. Magnetic bilayer-skyrmions without skyrmion Hall effect.

    PubMed

    Zhang, Xichao; Zhou, Yan; Ezawa, Motohiko

    2016-01-19

    Magnetic skyrmions might be used as information carriers in future advanced memories, logic gates and computing devices. However, there exists an obstacle known as the skyrmion Hall effect (SkHE), that is, the skyrmion trajectories bend away from the driving current direction due to the Magnus force. Consequently, the skyrmions in constricted geometries may be destroyed by touching the sample edges. Here we theoretically propose that the SkHE can be suppressed in the antiferromagnetically exchange-coupled bilayer system, since the Magnus forces in the top and bottom layers are exactly cancelled. We show that such a pair of SkHE-free magnetic skyrmions can be nucleated and be driven by the current-induced torque. Our proposal provides a promising means to move magnetic skyrmions in a perfectly straight trajectory in ultra-dense devices with ultra-fast processing speed.

  20. Computation of hypersonic laminar viscous flow past spinning sharp and blunt cones at high angle of attack

    NASA Technical Reports Server (NTRS)

    Agarwal, R.; Rakich, J. V.

    1978-01-01

    Computational results, obtained with a parabolic Navier-Stokes marching code, are presented for hypersonic viscous flow past spinning sharp and blunt cones at angle of attack. The code takes into account the asymmetries in the flow field resulting from spinning motion and computes the asymmetric shock shape, crossflow and streamwise shear, heat transfer, crossflow separation, and vortex structure. The Magnus force and moments are also computed. Comparisons are made with other theoretical analyses based on boundary-layer and boundary-region equations, and an anomaly is discovered in the displacement thickness contribution to the Magnus force when compared with boundary-layer results. In addition, a new criterion for defining crossflow separation behind spinning bodies is introduced which generalizes the Moore-Rott-Sears criterion for two-dimensional unsteady separation. A condition which characterizes the onset of separation in the flow field is defined.

  1. Byzantine doctrines on uroscopy in the Liber Orinalibus of Hermogenes (codex 69 Montecassino).

    PubMed

    Iorio, Luigi; Lamagna, Mario

    2011-01-01

    The Liber medicine orinalibus (codex 69 Montecassino) of Hermogenes is the first known manuscript to have a Latin translation from the original Greek work of Magnus of Emesa (or Nisibis). The particular text here translated, from the so-called Commentatio, mentions direct transliteration of Greek concepts such as chyma and hypostasis, suggesting that the Latin text derived directly from the Greek original, without the intermediation of Arabic translations. The implementation of our text is considered to have been undertaken in the city of Ravenna, which housed a medical school during the sixth century ad, or in southern Italy, with its scriptoria. Evidence of the presence of Latin translations of Greek medical texts in Calabria during the Gothic age is provided by Cassiodorus (Inst. 1, 31, 2). The Greek to Latin workshops testify to an uninterrupted activity of copying from Greek medical texts, with particular attention to the Iatrosophists of the Alexandrian school, of which Magnus was a representative.

  2. Numerical algorithms for highly oscillatory dynamic system based on commutator-free method

    NASA Astrophysics Data System (ADS)

    Li, Wencheng; Deng, Zichen; Zhang, Suying

    2007-04-01

    In the present paper, an efficiently improved modified Magnus integrator algorithm based on commutator-free method is proposed for the second-order dynamic systems with time-dependent high frequencies. Firstly, the second-order dynamic systems are transferred to the frame of reference by introducing new variable so that highly oscillatory behaviour inherited from the entries. Then the modified Magnus integrator method based on local linearization is appropriately designed for solving the above new form. And some optimized strategies for reducing the number of function evaluations and matrix operations are also suggested. Finally, several numerical examples for highly oscillatory dynamic systems, such as Airy equation, Bessel equation, Mathieu equation, are presented to demonstrate the validity and effectiveness of the proposed method.

  3. STS-112 crew walks out of O&C building before launch

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- Still waving at spectators, the STS-112 crew heads for the Astrovan that will take them to Launch Pad 39B and Space Shuttle Atlantis. Liftoff is scheduled for 3:46 p.m. EDT. From left are Mission Specialists Fyodor Yurchikhin David Wolf, and Piers Sellers; Pilot Pamela Melroy; Mission Specialist Sandra Magnus; and Commander Jeffrey Ashby. Sellers, Magnus and Yurchikhin are making their first Shuttle flights. STS-112 is the 15th assembly flight to the International Space Station, carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts. On the 11-day mission, three spacewalks are planned to attach the S1 truss to the Station.

  4. STS-112 crew after arrival at SLF for launch

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- The STS-112 crew pauses for a photo after their arrival at the KSC Shuttle Landing Facility. Standing, left to right, are Mission Specialist Piers Sellers, Pilot Pamela Melroy, Commander Jeffrey Ashby, and Mission Specialists David Wolf, Sandra Magnus and cosmonaut Fyodor Yurchikhin. Sellers, Magnus and Yurchikhin are making their first Shuttle flights. STS-112, aboard Space Shuttle Atlantis, is the 15th assembly mission to the International Space Station. Atlantis will be carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts. The 11-day mission includes three spacewalks. Launch is scheduled for Oct. 2 between 2 and 6 p.m.

  5. Paradoxical pop-ups: Why are they difficult to catch?

    NASA Astrophysics Data System (ADS)

    McBeath, Michael K.; Nathan, Alan M.; Bahill, A. Terry; Baldwin, David G.

    2008-08-01

    Professional baseball players occasionally find it difficult to gracefully approach seemingly routine pop-ups. We describe a set of towering pop-ups with trajectories that exhibit cusps and loops near the apex. For a normal fly ball the horizontal velocity continuously decreases due to drag caused by air resistance. For pop-ups the Magnus force is larger than the drag force. In these cases the horizontal velocity initially decreases like a normal fly ball, but after the apex, the Magnus force accelerates the horizontal motion. We refer to this class of pop-ups as paradoxical because they appear to misinform the typically robust optical control strategies used by fielders and lead to systematic vacillation in running paths, especially when a trajectory terminates near the fielder. Former major league infielders confirm that our model agrees with their experiences.

  6. Magnetic bilayer-skyrmions without skyrmion Hall effect

    PubMed Central

    Zhang, Xichao; Zhou, Yan; Ezawa, Motohiko

    2016-01-01

    Magnetic skyrmions might be used as information carriers in future advanced memories, logic gates and computing devices. However, there exists an obstacle known as the skyrmion Hall effect (SkHE), that is, the skyrmion trajectories bend away from the driving current direction due to the Magnus force. Consequently, the skyrmions in constricted geometries may be destroyed by touching the sample edges. Here we theoretically propose that the SkHE can be suppressed in the antiferromagnetically exchange-coupled bilayer system, since the Magnus forces in the top and bottom layers are exactly cancelled. We show that such a pair of SkHE-free magnetic skyrmions can be nucleated and be driven by the current-induced torque. Our proposal provides a promising means to move magnetic skyrmions in a perfectly straight trajectory in ultra-dense devices with ultra-fast processing speed. PMID:26782905

  7. Collective Transport Properties of Driven Skyrmions with Random Disorder

    NASA Astrophysics Data System (ADS)

    Reichhardt, C.; Ray, D.; Reichhardt, C. J. Olson

    2015-05-01

    We use particle-based simulations to examine the static and driven collective phases of Skyrmions interacting with random quenched disorder. We show that nondissipative effects due to the Magnus term reduce the depinning threshold and strongly affect the Skyrmion motion and the nature of the dynamic phases. The quenched disorder causes the Hall angle to become drive dependent in the moving Skyrmion phase, while different flow regimes produce distinct signatures in the transport curves. For weak disorder, the Skyrmions form a pinned crystal and depin elastically, while for strong disorder the system forms a pinned amorphous state that depins plastically. At high drives the Skyrmions can dynamically reorder into a moving crystal, with the onset of reordering determined by the strength of the Magnus term.

  8. Computation of supersonic turbulent flow past a spinning cone

    NASA Technical Reports Server (NTRS)

    Agarwal, R. K.

    1982-01-01

    Computational results are presented for supersonic laminar and turbulent flow past a pointed cone at angle of attack obtained with a parabolic Navier-Stokes marching code. The code takes into account the asymmetries in the flowfield resulting from spinning motion and computes the asymmetric shock shape, crossflow and streamwise shear, heat transfer, crossflow separation, and vortex structure. The Magnus force and moments are also computed. Comparisons are made with other analyses based on boundary-layer equations. For certain laminar flow conditions, an anomaly is discovered in the displacement thickness contribution to the Magnus force when compared with boundary-layer results. For turbulent flow, at small angles of attack, good agreement is obtained with the experimental data and other theoretical results.

  9. Magnetic bilayer-skyrmions without skyrmion Hall effect

    NASA Astrophysics Data System (ADS)

    Zhang, Xichao; Zhou, Yan; Ezawa, Motohiko

    2016-01-01

    Magnetic skyrmions might be used as information carriers in future advanced memories, logic gates and computing devices. However, there exists an obstacle known as the skyrmion Hall effect (SkHE), that is, the skyrmion trajectories bend away from the driving current direction due to the Magnus force. Consequently, the skyrmions in constricted geometries may be destroyed by touching the sample edges. Here we theoretically propose that the SkHE can be suppressed in the antiferromagnetically exchange-coupled bilayer system, since the Magnus forces in the top and bottom layers are exactly cancelled. We show that such a pair of SkHE-free magnetic skyrmions can be nucleated and be driven by the current-induced torque. Our proposal provides a promising means to move magnetic skyrmions in a perfectly straight trajectory in ultra-dense devices with ultra-fast processing speed.

  10. Vortex dynamics in self-dual Chern-Simons-Higgs systems

    SciTech Connect

    Kim, Y. ); Lee, K. )

    1994-02-15

    We consider vortex dynamics in self-dual Chern-Simons-Higgs systems. We show that the naive Aharonov-Bohm phase is the inverse of the statistical phase expected from the vortex spin, and that the self-dual configurations of vortices are degenerate in energy but not in angular momentum. We also use the path integral formalism to derive the dual formulation of Chern-Simons-Higgs systems in which vortices appear as charged particles. We argue that in addition to the electromagnetic interaction, there is an additional interaction between vortices, the so-called Magnus force, and that these forces can be put together into a single dual electromagnetic'' interaction. This dual electromagnetic interaction leads to the right statistical phase. We also derive and study the effective action for slowly moving vortices, which contains terms both linear and quadratic in the vortex velocity. We show that vortices can be bounded to each other by the Magnus force.

  11. Exploring unconventional capabilities of holographic tweezers

    NASA Astrophysics Data System (ADS)

    Hernandez, R. J.; Pagliusi, P.; Provenzano, C.; Cipparrone, G.

    2011-06-01

    We report an investigation of manipulation and trapping capabilities of polarization holographic tweezers. A polarization gradient connected with a modulation of the ellipticity shows an optical force related to the polarization of the light that can influence optically isotropic particles. While in the case of birefringent particles an unconventional trapping in circularly polarized fringes is observed. A liquid crystal emulsion has been adopted to investigate the capabilities of the holographic tweezers. The unusual trapping observed for rotating bipolar nematic droplets has suggested the involvement of the lift hydrodynamic force responsible of the Magnus effect, originating from the peculiar optical force field. We show that the Magnus force which is ignored in the common approach can contribute to unconventional optohydrodynamic trapping and manipulation.

  12. JPRS Report, West Europe

    DTIC Science & Technology

    2007-11-02

    Economy Through 1989 (Jan Magnus Fahlstrom; DAGENS NYHETER, 9 Apr 87) 98 SOCIAL SWEDEN Lapps Weigh Emigration Following Chernobyl Devastation...after Chernobyl the Soviet state is a bogeyman for the rest of the world—in human terms, economically and in the area of envir- onmental technology...election year." 11798 , CS0: 3650/102 99 „«„■P»T SWEDEN SOCIAL LAPPS WEIGH EMIGRATION FOLLOWING CHERNOBYL DEVASTATION Stockholm DAGENS NYHETER

  13. STS-112 takes part in post-landing briefing for the media

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- The STS-112 crew takes part in a post-landing briefing for the media. From left are Mission Specialists David Wolf, Sandra Magnus, responding to a question, and Piers Sellers. Mission STS-112 was the 15th assembly flight to the International Space Station, installing the S1 truss. The landing was the 60th at KSC in the history of the Shuttle program.

  14. Efficient numerical integration of neutrino oscillations in matter

    NASA Astrophysics Data System (ADS)

    Casas, F.; D'Olivo, J. C.; Oteo, J. A.

    2016-12-01

    A special purpose solver, based on the Magnus expansion, well suited for the integration of the linear three neutrino oscillations equations in matter is proposed. The computations are speeded up to two orders of magnitude with respect to a general numerical integrator, a fact that could smooth the way for massive numerical integration concomitant with experimental data analyses. Detailed illustrations about numerical procedure and computer time costs are provided.

  15. Polarization effects due to the mutual influence of trajectory parameters and polarization

    NASA Astrophysics Data System (ADS)

    Sadykov, N. R.

    2006-10-01

    In the geometric optics approximation, we comparatively analyze the polarization effects resulting from the influence of polarization on the beam trajectory. We show that the beam trajectory equations describing the optical Magnus effect that are obtained from the canonical Hamilton equations, Fermat principle, and truncated vector wave equations give the same result, coincident with the result in the mode approach. We explain the reasons underlying the previously derived results.

  16. A Review: Numerical Modeling of the Debris Throw of Reinforced Concrete Structures Under Internal Explosions

    DTIC Science & Technology

    2010-07-15

    especially in the early stage of the trajectory is questionable. TNO study on debris cloud • Debris spinning creating the “ Magnus Effect” Spinning...launch; debris trajectory and post ground impact. Results from the simulations of the various stages have been presented and discussed in previous...launch, 4) debris trajectory and 5) post ground impact. It must be recognised that these 5 phases are not cleanly demarcated in time and they are

  17. Theoretical Studies of Gas Phase Elementary Reactions

    DTIC Science & Technology

    2009-11-30

    matrix propagation and the Magnus expansion of the time evolution operator. The scheme combines formally accurate quantum propagation of electrons...beginning of the N3 trajectory , and the large grey dots the conical intersections encountered. [sa(4)- CASSCF(15e/12o)/aug-cc-pVTZ level]. 3 as...photodissociation dynamics of H2CO is known to involve S1, T1 and S0. Recent quasiclassical trajectory (QCT) calculations in conjunction with

  18. The Ecology and Environmental Impacts of Hydrilla

    DTIC Science & Technology

    1992-10-15

    guadalupensis (Spreng.) Magnus) and egeria ( Egeria densa ) were the dominant submersed weeds. The other aquatic plants were found only in small areas of...naiad and egeria became a problem in several areas of the lake; but by late fall, the submersed weed growth was still a minor problem. Local state...species having the greatest frequencies of occurrence were egeria , southern naiad, and hydrilla. A second survey was made on May 28, 1974 to record

  19. Dynamics of skyrmions in chiral magnets: Dynamic phase transitions and equation of motion

    SciTech Connect

    Lin, Shi-Zeng Reichhardt, Charles; Batista, Cristian D.; Saxena, Avadh

    2014-05-07

    We study the dynamics of skyrmions in a metallic chiral magnet. First, we show that skyrmions can be created dynamically by destabilizing the ferromagnetic background state through a spin polarized current. We then treat skyrmions as rigid particles and derive the corresponding equation of motion. The dynamics of skyrmions is dominated by the Magnus force, which accounts for the weak pinning of skyrmions observed in experiments. Finally, we discuss the quantum motion of skyrmions.

  20. Control Mechanism Strategies for Spin-Stabilized Projectiles

    DTIC Science & Technology

    2008-09-01

    maneuver footprint shape was dictated by the angle -of-fall and yaw of repose . Shallow angles -of-fall produced footprint ellipses, with a major axis...Magnus moments and yaw of repose . Adding a control mechanism such as fins to guide a spin- stabilized projectile further complicates the resulting...ratio), and the roll window over which the pulsed controller operated. The metrics of this analysis were the maneuver footprint, total angle of attack

  1. Proceedings of the International Symposium on the Application of Fundamental Theory to Problems of Biology and Pharmacology, Volume 70 No. 6

    DTIC Science & Technology

    2007-11-02

    Technion, Haifa, Israel John A. Pople Northwestern University at Evanston, Illinois, USA Alberte Pullman Institut de Biologie Physico - Chimique ...University at Evanston, Illinois, USA Alberte Pullman Institut de Biologie Physico - Chimique , Paris, France Paul von Rague Schleyer Universität...Seattle, USA Sten Rettrup H. C. ßrsted Institut, Copenhagen, Denmark C. Magnus L Rittby 7exas Christian University at Fort Worth, USA Michael Robb

  2. International Journal of Quantum Chemistry, Quantum Biology Symposium No. 24. Proceedings of the International Symposium on the Application of Fundamental Theory to Problems of Biology and Pharmacology, Held at Ponce de Leon Resort, St. Augustine, Florida on March 1-7, 1997. Volume 65, No. 6, 1997.

    DTIC Science & Technology

    1997-03-01

    Technion, Haifa, Israel John A. Pople Northwestern University at Evanston, Illinois, USA Alberte Pullman Institut de Biologie Physico - Chimique , Paris...Institut de Biologie Physico - Chimique , Paris, France Paul von Raguö Schleyer Universität Erlangen-Nürnberg, Erlangen, Germany Harrison Shull Naval...Au William Reinhardt University of Washington at Sean Sten Rettrup H. C. Orsted Institut, Copenhagen C. Magnus L Rittby Texas Christian

  3. The importance of soft tissue stabilization in trans-femoral amputation : English version.

    PubMed

    Gottschalk, F

    2016-03-01

    Transfemoral amputations with more proximal amputation levels have the problem of secondary development into flexion and abduction contractures. This is induced by muscle imbalance, especially the loss of adductor muscle insertions when abductor muscle insertions are preserved. This causes considerable problems when fitting prosthetics. Myodesis with insertion of the distally detached adductor magnus muscle to the lateral femoral cortex, introduced here, results in a stronger stump with good muscle balance, and prosthetics fitting is significantly improved.

  4. STS-112 Crew Portrait

    NASA Technical Reports Server (NTRS)

    2002-01-01

    JOHNSON SPACE CENTER, HOUSTON, TEXAS -- (STS112-S-002) These five astronauts and cosmonaut take a break from training to pose for the STS-112 crew portrait. Astronauts Pamela A. Melroy and Jeffrey S. Ashby, pilot and commander respectively, are in the cen ter of the photo. The mission specialists are from left to right, astronauts Sandra H. Magnus, David A. Wolf and Piers J. Sellers, and cosmonaut Fyodor Yurchikhin, who represents Rosaviakosmos.

  5. Fußball mit Wissenschaftlichem Maß: Bananenflanken, Flatterbälle, Kopfballkämpfe

    NASA Astrophysics Data System (ADS)

    Mathelitsch, Leopold; Thaller, Sigrid

    2006-05-01

    Die physikalische Betrachtung des Fußballs liefert spannende Resultate. Wegen der geringen Torzahl spielt der Zufall bei Sieg oder Niederlage stärker mit als in anderen Sportarten. Fußball ist daher mit gewissen statistischen Eigenschaften radioaktiver Quellen vergleichbar. Gleich mehrere physikalische Effekte beeinflussen die Flugbahn des Balls. Der Magnus-Effekt zum Beispiel ermöglicht erst Bananenflanken. Pfeift ein Schiedsrichter falsch, dann wird er nicht selten von seiner Sehperspektive getäuscht.

  6. [Book review] The Sound Approach to Birding: A Guide to Understanding Bird Sound. --Mark Constantine and The Sound Approach. 2006. Poole, Dorset, United Kingdom.192 pp. + 2 CDs

    USGS Publications Warehouse

    Robbins, C.S.

    2007-01-01

    What is the ?Sound Approach?? It is a trio of enthusiastic bird-sound recordists?analysts (Arnoud B. van den Berg, Mark Constantine, and Magnus Robb) who, with friends, traveled to 42 countries in a massive effort to record all the songs and calls of the birds of the Western Palearctic. The recordings in this guide are selected from the 30,000 or so recorded digitally with stereo microphones by the authors since the year 2000.

  7. US Army War College Information Operations Primer

    DTIC Science & Technology

    2009-11-01

    Steve Iatrou from the Information Operations Center of Excellence, Naval Postgraduate School: Mr. Paul Palmer and COL Mike Dominique USA, both...International Transformation Conference, June 3, 2009). 5 Cebrowski, 7. 6 Magnus Ekman et al., An In-Depth Look at Computer Performance Growth, Technical...Dominique Program Manage/Deputy Mr. Paul Palmer; YC-02 OPERATIONS Chief of Operations Mr. Cameron M. Wesson; YC-02 Information Engagements Ms

  8. Clinics in diagnostic imaging (71). Left iliopsoas abscess secondary to vertebral osteomyelitis.

    PubMed

    Muttarak, M; Peh, W C G

    2002-03-01

    A 26-year-old woman presented with a progressively painful lump at her left groin and upper thigh for five months. She also had intermittent back pain for three years. Radiographs and CT showed osteolytic destruction of the several contiguous thoracolumbar vertebrae with a large left iliopsoas abscess that extended to involve the left gluteus maximus and adductor magnus muscles. She responded well to a course of antibiotics. The role of imaging and imaging features of iliopsoas abscesses are discussed, together

  9. New Numerical Integrators Based on Solvability and Splitting

    DTIC Science & Technology

    2007-11-02

    display a currently valid OMB control number. 1. REPORT DATE 03 JAN 2005 2. REPORT TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE New...Group Methods And Control Theory Workshop Held on 28 June 2004 - 1 July 2004., The original document contains color images. 14. ABSTRACT 15...Mechanics, NMR spectroscopy, infrared divergences in QED, control theory,... 1.1 Magnus expansion (IV) NEW NUMERICAL INTEGRATORS BASED ON SOLVABILITY AND

  10. Removing Boundary Layer by Suction

    NASA Technical Reports Server (NTRS)

    Ackeret, J

    1927-01-01

    Through the utilization of the "Magnus effect" on the Flettner rotor ship, the attention of the public has been directed to the underlying physical principle. It has been found that the Prandtl boundary-layer theory furnishes a satisfactory explanation of the observed phenomena. The present article deals with the prevention of this separation or detachment of the flow by drawing the boundary layer into the inside of a body through a slot or slots in its surface.

  11. Physical optics in a uniform gravitational field

    NASA Astrophysics Data System (ADS)

    Hacyan, Shahen

    2012-01-01

    The motion of a (quasi-)plane wave in a uniform gravitational field is studied. It is shown that the energy of an elliptically polarized wave does not propagate along a geodesic, but in a direction that is rotated with respect to the gravitational force. The similarity with the walk-off effect in anisotropic crystals or the optical Magnus effect in inhomogeneous media is pointed out.

  12. The algebraic criteria for the stability of control systems

    NASA Technical Reports Server (NTRS)

    Cremer, H.; Effertz, F. H.

    1986-01-01

    This paper critically examines the standard algebraic criteria for the stability of linear control systems and their proofs, reveals important previously unnoticed connections, and presents new representations. Algebraic stability criteria have also acquired significance for stability studies of non-linear differential equation systems by the Krylov-Bogoljubov-Magnus Method, and allow realization conditions to be determined for classes of broken rational functions as frequency characteristics of electrical network.

  13. Quantum depinning in layered superconductors with defects produced by irradiation

    SciTech Connect

    Bulaevskii, L.N.; Larkin, A.I.; Maley, M.P.; Vinokur, V.M.

    1995-10-01

    We consider Magnus force vortex dynamics in superclean superconductors and calculate the quantum tunneling rate of the pancake vortex creep from the pinning cites in the nondissipative limit. The consideration is based on the exact representation of the one-particle wave functions in the magnetic and electric fields. The obtained results are compared to the experimental data and the possibility of the observation of the discrete structure of the pinned pancake energy levels is discussed.

  14. Earth matter effect on active-sterile neutrino oscillations

    NASA Astrophysics Data System (ADS)

    Acero, Mario A.; Aguilar-Arevalo, Alexis A.; D'Olivo, J. C.

    2011-08-01

    Oscillations between active and sterile neutrinos remain as an open possibility to explain some experimental observations. In a four-neutrino mixing scheme, we use the Magnus expansion of the evolution operator to study the evolution of neutrino flavor amplitudes within the Earth. We apply this formalism to calculate the transition probabilities from active to sterile neutrinos taking into account the matter effect for a varying terrestrial density.

  15. Substitution of Wax and Grease Cleaners With Biodegradable Solvents: Phase 1. Part 2

    DTIC Science & Technology

    1989-09-01

    FREMONT INDUSTRIES GAF CORP. GAMAGET EQUIPMENT, DIV SYBRON CHEMICALS INC. GENERAL TEXAS CORP. 68 GETTY REFINING CO. GIVANDEN CORP. GOODRICH PROJUCT DIV...CHEMICAL PRODUCTS LUFKIN CORP. M-OIL-FREE CO. MACDER!MID CORP. MADISON BIONICS MAGIE BROS. OIL CO. MAGNA IND. CO. LTD. MAGNUS DIV OF ECONOOMICAL LABORATORY...CO. STARKEY CHEMICAL PROCESS CO. STEPAN CO. STERLING-CLARK-LURTON CORP. 71 SUN REFINING & MARKETING CO. SURFACE DYNAMICS USA INC. SUTTON CORP. SWI

  16. Anatomy of the septomarginal trabecula in goat hearts.

    PubMed

    Leão, Camila Ribeiro; Pacha, Diego Lago; Cyriaco, Thiago; da Silva, Cavalcante; Wafae, Nader; Pereira, Heloisa Maria Lemes; Ruiz, Cristiane Regina

    2010-01-01

    Our aim in this study was to examine the right septomarginal trabecula of goats regarding the frequency, origin course of the septal and free component, attachment to the papillaris magnus muscle and size . The material used consisted in 32 hearts from non-pedigree goats of both sexes, preserved in 10% formalin. The right septomarginal trabecula was present in all hearts. It could also present a prominence in the form of a cord in the septum before detaching and going towards the wall or the papillary muscle. We called this a septal component and found it in 69% of all hearts studied. In the remaining specimens, the exit of the septomarginal trabecula was abrupt, without presenting a septal component. It could be attached solely to the papillaris magnus muscle or to the papillary muscle and the ventricle wall, originated in the cranial third of the septum, and was attached to the middle third of the papillary muscle or its caudal third. Its free part, from the septum to the papillaris magnus muscle, ranged in length from 1.3 cm to 2.6 cm. The mean value was 1.7 cm, and the most frequent values were 1.9 and 1.5 cm. In conclusion, in goats, the septomarginal trabecula is a constant and invariable structure.

  17. Reactive high power impulse magnetron sputtering

    NASA Astrophysics Data System (ADS)

    Gudmundsson, J. T.; Magnus, F.; Tryggvason, T. K.; Sveinsson, O. B.; Olafsson, S.

    2012-10-01

    Here we discuss reactive high power impulse magnetron sputtering sputtering (HiPIMS) [1] of Ti target in an Ar/N2 and Ar/O2 atmosphere. The discharge current waveform is highly dependent on both the pulse repetition frequency and discharge voltage. The discharge current increases with decreasing frequency or voltage. This we attribute to an increase in the secondary electron emission yield during the self-sputtering phase of the pulse, as nitride [2] or oxide [3] forms on the target. We also discuss the growth of TiN films on SiO2 at temperatures of 22-600 ^oC. The HiPIMS process produces denser films at lower growth temperature and the surface is much smoother and have a significantly lower resistivity than dc magnetron sputtered films on SiO2 at all growth temperatures due to reduced grain boundary scattering [4].[4pt] [1] J. T. Gudmundsson, N. Brenning, D. Lundin and U. Helmersson, J. Vac. Sci. Technol. A, 30 030801 (2012)[0pt] [2] F. Magnus, O. B. Sveinsson, S. Olafsson and J. T. Gudmundsson, J. Appl. Phys., 110 083306 (2011)[0pt] [3] F. Magnus, T. K. Tryggvason, S. Olafsson and J. T. Gudmundsson, J. Vac. Sci. Technol., submitted 2012[0pt] [4] F. Magnus, A. S. Ingason, S. Olafsson and J. T. Gudmundsson, IEEE Elec. Dev. Lett., accepted 2012

  18. Ratchet Effects, Negative Mobility, and Phase Locking for Skyrmions on Periodic Substrates

    NASA Astrophysics Data System (ADS)

    Reichhardt, Charles; Ray, Dipanjan; Olson Reichhardt, Cynthia

    We examine the dynamics of skyrmions interacting with 1D and 2D periodic substrates in the presence of dc and ac drives. We find that the Magnus term strongly affects the skyrmion dynamics and that new kinds of phenomena can occur which are absent for overdamped ac and dc driven particles interacting with similar substrates. We show that it is possible to realize a Magnus induced ratchet for skyrmions interacting with an asymmetric potential, where the application of an ac drive can produce quantized dc motion of the skyrmions even when the ac force is perpendicular to the substrate asymmetry direction. For symmetric substrates it is also possible to achieve a negative mobility effect where the net skyrmion motion runs counter to an applied dc drive. Here, as a function of increasing dc drive, the velocity-force curves show a series of locking phases that have different features from the classic Shapiro steps found in overdamped systems. In the phase locking and ratcheting states, the skyrmions undergo intricate 2D orbits induced by the Magnus term.

  19. STS-112 Crew Training Clip

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Footage shows the crew of STS-112 (Jeffrey Ashby, Commander; Pamela Melroy, Pilot; David Wolf, Piers Sellers, Sandra Magnus, and Fyodor Yurchikhin, Mission Specialists) during several parts of their training. The video is arranged into short segments. In 'Topside Activities at the NBL', Wolf and Sellers are fitted with EVA suits for pool training. 'Pre-Launch Bailout Training in CCT II' shows all six crew members exiting from the hatch on a model of a shuttle orbiter cockpit. 'EVA Training in the VR Lab' shows a crew member training with a virtual reality simulator, interspersed with footage of Magnus, and Wolf with Melroy, at monitors. There is a 'Crew Photo Session', and 'Pam Melroy and Sandy Magnus at the SES Dome' also features a virtual reality simulator. The final two segments of the video involve hands-on training. 'Post Landing Egress at the FFT' shows the crew suiting up into their flight suits, and being raised on a harness, to practice rapelling from the cockpit hatch. 'EVA Prep and Post at the ISS Airlock' shows the crew assembling an empty EVA suit onboard a model of a module. The crew tests oxygen masks, and Sellers is shown on an exercise bicycle with an oxygen mask, with his heart rate monitored (not shown).

  20. Investigation on heavy liquid metal cooling of ADS fuel pin assemblies

    NASA Astrophysics Data System (ADS)

    Litfin, K.; Batta, A.; Class, A. G.; Wetzel, Th.; Stieglitz, R.

    2011-08-01

    In the framework of accelerator driven sub-critical reactor systems heavy liquid metals are considered as coolant for the reactor core and the spallation target. In particular lead or lead bismuth eutectic (LBE) exhibit efficient heat removal properties and high production rate of neutrons. However, the excellent heat conductivity of LBE-flows expressed by a low molecular Prandtl number of the order 10 -2 requires improved modeling of the turbulent heat transfer. Although various models for thermal hydraulics of LBE flows are existing, validated heat transfer correlations for ADS-relevant conditions are still missing. In order to validate the sub-channel codes and computational fluid dynamics codes used to design fuel assemblies, the comparison with experimental data is inevitable. Therefore, an experimental program composed of three major experiments, a single electrically heated rod, a 19-pin hexagonal water rod bundle and a LBE rod bundle, has been initiated at the Karlsruhe Liquid metal Laboratory (KALLA) of the Karlsruhe Institute of Technology, in order to quantify and separate the individual phenomena occurring in the momentum and energy transfer of a fuel assembly.

  1. ConnesFusionTensorProduct/Photon GluonFusion in Mitochondria

    NASA Astrophysics Data System (ADS)

    Wh-Maksoed, Prodi Of Physics Ui, Depok 16415-Indonesia; Ssi, Wh-Maksoed

    2016-05-01

    As in AJ Wassermann distinguished of classical invariant theory & quantum invariant theory subfactor, in S. Palcoux:``From Neveu-Schwarz Subfactors & Connes Fusion'' described the subfactor theory & Witt-algebra whereas Andreas Thom's explanation about ConnesFusionTensorProduct/CFTP related Connes fusion to composition of homomorphism (i). classical tensor product O-X adds the changes,(ii). Relative tensor product H-X preserve the changes. For photonGluonFusion/PGF defined:''photon is the gauge boson of QED, the simplest of all boson'' devotes to CFT as ``quantum field theory which are invariant under conformal transformation & in 2D there are infinite dimensional algebra. Alain Connes states theirselves Connes fusion as ``associative tensor operation'' to be in coincidences with ``their dynamic behavior driven by the balance in mitochondrial fusion & fission (Carveney, 2007) from Peter Alexander Williams: ``Retinal neuronal remodeling in a model of Optic Atrophy'', Dec, 2011. Great acknowledged to the VicePresident of the R.I, HE.Mr. Drs. M. JUSUF KALLA.

  2. Quantized transport for a skyrmion moving on a two-dimensional periodic substrate

    NASA Astrophysics Data System (ADS)

    Reichhardt, C.; Ray, D.; Reichhardt, C. J. Olson

    2015-03-01

    We examine the dynamics of a skyrmion moving over a two-dimensional periodic substrate utilizing simulations of a particle-based skyrmion model. We specifically examine the role of the nondissipative Magnus term on the driven motion and the resulting skyrmion velocity-force curves. In the overdamped limit, there is a depinning transition into a sliding state in which the skyrmion moves in the same direction as the external drive. When there is a finite Magnus component in the equation of motion, a skyrmion in the absence of a substrate moves at an angle with respect to the direction of the external driving force. When a periodic substrate is added, the direction of motion or Hall angle of the skyrmion is dependent on the amplitude of the external drive, only approaching the substrate-free limit for higher drives. Due to the underlying symmetry of the substrate the direction of skyrmion motion does not change continuously as a function of drive, but rather forms a series of discrete steps corresponding to integer or rational ratios of the velocity components perpendicular ( ) and parallel ( ) to the external drive direction: / =n /m , where n and m are integers. The skyrmion passes through a series of directional locking phases in which the motion is locked to certain symmetry directions of the substrate for fixed intervals of the drive amplitude. Within a given directionally locked phase, the Hall angle remains constant and the skyrmion moves in an orderly fashion through the sample. Signatures of the transitions into and out of these locked phases take the form of pronounced cusps in the skyrmion velocity versus force curves, as well as regions of negative differential mobility in which the net skyrmion velocity decreases with increasing external driving force. The number of steps in the transport curve increases when the relative strength of the Magnus term is increased. We also observe an overshoot phenomena in the directional locking

  3. Advances in Theory of Solid-State Nuclear Magnetic Resonance.

    PubMed

    Mananga, Eugene S; Moghaddasi, Jalil; Sana, Ajaz; Akinmoladun, Andrew; Sadoqi, Mostafa

    Recent advances in theory of solid state nuclear magnetic resonance (NMR) such as Floquet-Magnus expansion and Fer expansion, address alternative methods for solving a time-dependent linear differential equation which is a central problem in quantum physics in general and solid-state NMR in particular. The power and the salient features of these theoretical approaches that are helpful to describe the time evolution of the spin system at all times are presented. This review article presents a broad view of manipulations of spin systems in solid-state NMR, based on milestones theories including the average Hamiltonian theory and the Floquet theory, and the approaches currently developing such as the Floquet-Magnus expansion and the Fer expansion. All these approaches provide procedures to control and describe the spin dynamics in solid-state NMR. Applications of these theoretical methods to stroboscopic and synchronized manipulations, non-synchronized experiments, multiple incommensurated frequencies, magic-angle spinning samples, are illustrated. We also reviewed the propagators of these theories and discussed their convergences. Note that the FME is an extension of the popular Magnus Expansion and Average Hamiltonian Theory. It aims is to bridge the AHT to the Floquet Theorem but in a more concise and efficient formalism. Calculations can then be performed in a finite-dimensional Hilbert space instead of an infinite dimensional space within the so-called Floquet theory. We expected that the FME will provide means for more accurate and efficient spin dynamics simulation and for devising new RF pulse sequence.

  4. Phylogeny and species delineation in European species of the genus Steganacarus (Acari, Oribatida) using mitochondrial and nuclear markers.

    PubMed

    Kreipe, Victoria; Corral-Hernández, Elena; Scheu, Stefan; Schaefer, Ina; Maraun, Mark

    2015-06-01

    Species of the genus Steganacarus are soil-living oribatid mites (Acari, Phthiracaridae) with a ptychoid body. The phylogeny and species status of the species of Steganacarus are not resolved, some authors group all ten German species of Steganacarus within the genus Steganacarus whereas others split them into three subgenera, Steganacarus, Tropacarus and Atropacarus. Additionally, two species, S. magnus and T. carinatus, comprise morphotypes of questionable species status. We investigated the phylogeny and species status of ten European Steganacarus species, i.e. S. applicatus, S. herculeanus, S. magnus forma magna, S. magnus forma anomala, S. spinosus, Tropacarus brevipilus, T. carinatus forma carinata, T. carinatus forma pulcherrima, Atropacarus striculus and Rhacaplacarus ortizi. We used two molecular markers, a 251 bp fragment of the nuclear gene 28S rDNA (D3) and a 477 bp fragment of the mitochondrial COI region. The phylogeny based on a combined analysis of D3 and COI separated four subgenera (Steganacarus, Tropacarus and Atropacarus, Rhacaplacarus) indicating that they form monophyletic groups. The COI region separated all ten species of the genus Steganacarus and showed variation within some species often correlating with the geographic origin of the species. Resolution of the more conserved D3 region was limited, indicating that radiation events are rather recent. Overall, our results indicate that both genes alone cannot be used for phylogeny and barcoding since variation is too low in D3 and too high in COI. However, when used in combination these genes provide reliable insight into the phylogeny, radiation and species status of taxa of the genus Steganacarus.

  5. Enstrophy-based proper orthogonal decomposition of flow past rotating cylinder at super-critical rotating rate

    NASA Astrophysics Data System (ADS)

    Sengupta, Tapan K.; Gullapalli, Atchyut

    2016-11-01

    Spinning cylinder rotating about its axis experiences a transverse force/lift, an account of this basic aerodynamic phenomenon is known as the Robins-Magnus effect in text books. Prandtl studied this flow by an inviscid irrotational model and postulated an upper limit of the lift experienced by the cylinder for a critical rotation rate. This non-dimensional rate is the ratio of oncoming free stream speed and the surface speed due to rotation. Prandtl predicted a maximum lift coefficient as CLmax = 4π for the critical rotation rate of two. In recent times, evidences show the violation of this upper limit, as in the experiments of Tokumaru and Dimotakis ["The lift of a cylinder executing rotary motions in a uniform flow," J. Fluid Mech. 255, 1-10 (1993)] and in the computed solution in Sengupta et al. ["Temporal flow instability for Magnus-robins effect at high rotation rates," J. Fluids Struct. 17, 941-953 (2003)]. In the latter reference, this was explained as the temporal instability affecting the flow at higher Reynolds number and rotation rates (>2). Here, we analyze the flow past a rotating cylinder at a super-critical rotation rate (=2.5) by the enstrophy-based proper orthogonal decomposition (POD) of direct simulation results. POD identifies the most energetic modes and helps flow field reconstruction by reduced number of modes. One of the motivations for the present study is to explain the shedding of puffs of vortices at low Reynolds number (Re = 60), for the high rotation rate, due to an instability originating in the vicinity of the cylinder, using the computed Navier-Stokes equation (NSE) from t = 0 to t = 300 following an impulsive start. This instability is also explained through the disturbance mechanical energy equation, which has been established earlier in Sengupta et al. ["Temporal flow instability for Magnus-robins effect at high rotation rates," J. Fluids Struct. 17, 941-953 (2003)].

  6. Advances in Theory of Solid-State Nuclear Magnetic Resonance

    PubMed Central

    Mananga, Eugene S.; Moghaddasi, Jalil; Sana, Ajaz; Akinmoladun, Andrew; Sadoqi, Mostafa

    2015-01-01

    Recent advances in theory of solid state nuclear magnetic resonance (NMR) such as Floquet-Magnus expansion and Fer expansion, address alternative methods for solving a time-dependent linear differential equation which is a central problem in quantum physics in general and solid-state NMR in particular. The power and the salient features of these theoretical approaches that are helpful to describe the time evolution of the spin system at all times are presented. This review article presents a broad view of manipulations of spin systems in solid-state NMR, based on milestones theories including the average Hamiltonian theory and the Floquet theory, and the approaches currently developing such as the Floquet-Magnus expansion and the Fer expansion. All these approaches provide procedures to control and describe the spin dynamics in solid-state NMR. Applications of these theoretical methods to stroboscopic and synchronized manipulations, non-synchronized experiments, multiple incommensurated frequencies, magic-angle spinning samples, are illustrated. We also reviewed the propagators of these theories and discussed their convergences. Note that the FME is an extension of the popular Magnus Expansion and Average Hamiltonian Theory. It aims is to bridge the AHT to the Floquet Theorem but in a more concise and efficient formalism. Calculations can then be performed in a finite-dimensional Hilbert space instead of an infinite dimensional space within the so-called Floquet theory. We expected that the FME will provide means for more accurate and efficient spin dynamics simulation and for devising new RF pulse sequence. PMID:26878063

  7. Bioactive Mimetics of Conotoxins and other Venom Peptides

    PubMed Central

    Duggan, Peter J.; Tuck, Kellie L.

    2015-01-01

    Ziconotide (Prialt®), a synthetic version of the peptide ω-conotoxin MVIIA found in the venom of a fish-hunting marine cone snail Conus magnus, is one of very few drugs effective in the treatment of intractable chronic pain. However, its intrathecal mode of delivery and narrow therapeutic window cause complications for patients. This review will summarize progress in the development of small molecule, non-peptidic mimics of Conotoxins and a small number of other venom peptides. This will include a description of how some of the initially designed mimics have been modified to improve their drug-like properties. PMID:26501323

  8. New Staphylinidae (Coleoptera) records with new collection data from New Brunswick, Canada: Omaliinae, Micropeplinae, Phloeocharinae, Olisthaerinae, and Habrocerinae

    PubMed Central

    Webster, Reginald P.; Sweeney, Jon D.; DeMerchant, Ian

    2012-01-01

    Abstract Eleven species of Omaliinae are newly recorded from New Brunswick, bringing the total number of species known from the province to 32 described species. Supporting data are presented for the New Brunswick record of Geodromicus strictus (Fauvel) reported by Majka et al. (2011). Micropeplus browni Campbell, Micropeplus laticollis Mäklin (Micropeplinae), Charyhyphus picipennis (LeConte) (Phloeocharinae), Olisthaerus substriatus (Paykull) (Olisthaerinae), Habrocerus capillaricornis (Gravenhorst), Habrocerus magnus LeConte, and Habrocerus schwarzi Horn (Habrocerinae) are also newly recorded for New Brunswick. These are the first records of the latter four subfamilies from New Brunswick. Collection and bionomic data are presented for each species and discussed. PMID:22577316

  9. A revision of the Chinese Aulacidae (Hymenoptera, Evanioidea)

    PubMed Central

    Chen, Hua-yan; Turrisi, Giuseppe Fabrizio; Xu, Zai-fu

    2016-01-01

    Abstract The Chinese Aulacidae are revised, keyed and illustrated for the first time. In total twenty-five species are recorded from China, included within two genera Aulacus Jurine, 1807 and Pristaulacus Kieffer, 1900, with five and twenty species respectively. Among the treated species, six are newly described for science: Aulacus magnus sp. n., Pristaulacus calidus sp. n., Pristaulacus centralis sp. n., Pristaulacus fopingi sp. n., Pristaulacus obscurus sp. n., and Pristaulacus pseudoiosephi sp. n. Three species are newly recorded from China: Pristaulacus excisus Turner, 1922, Pristaulacus iosephi Turrisi & Madl, 2013, and Pristaulacus rufobalteatus Cameron, 1907. PMID:27408528

  10. Involvement of medullary serotonergic groups in multiple system atrophy.

    PubMed

    Benarroch, Eduardo E; Schmeichel, Ann M; Low, Phillip A; Parisi, Joseph E

    2004-03-01

    We sought to determine whether medullary serotonergic neurons were affected in multiple system atrophy (MSA). Immunostaining for tryptophan hydroxylase was performed on serial 50 microm sections of the medulla of brains obtained at autopsy from six control subjects, eight subjects with clinical diagnosis of MSA, and four with Parkinson's disease. There was a severe depletion of serotonergic neurons in the nucleus raphe magnus, raphe obscurus, raphe pallidus, and ventrolateral medulla in MSA. Depletion of serotonergic neurons may contribute to impaired control of sympathetic outflow and other abnormalities in MSA.

  11. STS-112 crew post-landing briefing for the media

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- The STS-112 crew takes part in a post-landing briefing for the media. Moderating, at left, is George Diller, with the NASA News Center. The crew, from left, are Commander Jeffrey Ashby, Pilot Pamela Melroy and Mission Specialists David Wolf, Sandra Magnus, Piers Sellers and cosmonaut Fyodor Yurchikhin. Mission STS-112 was the 15th assembly flight to the International Space Station, installing the S1 truss. The landing was the 60th at KSC in the history of the Shuttle program.

  12. Rigorous Bound on Energy Absorption and Generic Relaxation in Periodically Driven Quantum Systems

    NASA Astrophysics Data System (ADS)

    Mori, Takashi; Kuwahara, Tomotaka; Saito, Keiji

    2016-03-01

    We discuss the universal nature of relaxation in isolated many-body quantum systems subjected to global and strong periodic driving. Our rigorous Floquet analysis shows that the energy of the system remains almost constant up to an exponentially long time in frequency for arbitrary initial states and that an effective Hamiltonian obtained by a truncation of the Floquet-Magnus expansion is a quasiconserved quantity in a long time scale. These two general properties lead to an intriguing classification on the initial stage of relaxation, one of which is similar to the prethermalization phenomenon in nearly integrable systems.

  13. Kato expansion in quantum canonical perturbation theory

    NASA Astrophysics Data System (ADS)

    Nikolaev, Andrey

    2016-06-01

    This work establishes a connection between canonical perturbation series in quantum mechanics and a Kato expansion for the resolvent of the Liouville superoperator. Our approach leads to an explicit expression for a generator of a block-diagonalizing Dyson's ordered exponential in arbitrary perturbation order. Unitary intertwining of perturbed and unperturbed averaging superprojectors allows for a description of ambiguities in the generator and block-diagonalized Hamiltonian. We compare the efficiency of the corresponding computational algorithm with the efficiencies of the Van Vleck and Magnus methods for high perturbative orders.

  14. Quantum skyrmions in two-dimensional chiral magnets

    NASA Astrophysics Data System (ADS)

    Takashima, Rina; Ishizuka, Hiroaki; Balents, Leon

    2016-10-01

    We study the quantum mechanics of magnetic skyrmions in the vicinity of the skyrmion-crystal to ferromagnet phase boundary in two-dimensional magnets. We show that the skyrmion excitation has an energy dispersion that splits into multiple bands due to the combination of magnus force and the underlying lattice. Condensation of the skyrmions can give rise to an intermediate phase between the skyrmion crystal and ferromagnet: a quantum liquid, in which skyrmions are not spatially localized. We show that the critical behavior depends on the spin size S and the topological number of the skyrmion. Experimental signatures of quantum skyrmions in inelastic neutron-scattering measurements are also discussed.

  15. Quasi-Periodically Driven Quantum Systems

    NASA Astrophysics Data System (ADS)

    Verdeny, Albert; Puig, Joaquim; Mintert, Florian

    2016-10-01

    Floquet theory provides rigorous foundations for the theory of periodically driven quantum systems. In the case of non-periodic driving, however, the situation is not so well understood. Here, we provide a critical review of the theoretical framework developed for quasi-periodically driven quantum systems. Although the theoretical footing is still under development, we argue that quasi-periodically driven quantum systems can be treated with generalisations of Floquet theory in suitable parameter regimes. Moreover, we provide a generalisation of the Floquet-Magnus expansion and argue that quasi-periodic driving offers a promising route for quantum simulations.

  16. Dynamics of two-dimensional vortex pairs in a spatially varying potential

    NASA Astrophysics Data System (ADS)

    Lee, H. H.; Gunn, J. M. F.

    1992-10-01

    We consider the dynamics of vortices in a superfluid 4He film flowing over a substrate at zero temperature. The vortex trajectories are assumed to be governed by the Magnus-force equation with the effect of the substrate incorporated via the gradient of a potential. We use an equivalent Hamiltonian formulation to show that two vortices in a slowly varying potential can exhibit stochastic behavior. In this regard, there are differences between the cases of two vortices of the same sign and those of the opposite sign, the latter becoming stochastic more readily.

  17. Time-dependent perturbation theory for inelastic scattering

    NASA Astrophysics Data System (ADS)

    Cross, R. J.

    1982-08-01

    We show by numerical integration that the first-order, time-dependent, Magnus approximation agrees with the first-order, exponential, distorted-wave approximation to within a few percent, provided that the trajectory used for the time-dependent calculation is characterized by the arithmetic mean of the initial and final velocities and the arithmetic mean of the initial and final orbital angular momenta. Calculations are done for rotational energy transfer from an exponentially repulsive potential characteristic of He+H2 and for a Lennard-Jones potential characteristic of Ar+N2.

  18. Symmetric missile dynamic instabilities: A review

    NASA Astrophysics Data System (ADS)

    Murphy, C. H.

    1980-03-01

    Dynamic instabilities observed for symmetric missiles and projectiles arise from a large variety of causes. These include unstable linear damping moments, and different nonlinear in-plane and out-of-plane damping moments for nonspinning re-entry vehicles, nonlinear Magnus moments for spinning missiles, and internal resonance with moving payload components. If aerodynamic trim is present, linear spin-yaw resonance can occur as well as nonlinear subharmonic motions and a number of other limit motions. This report gives a complete survey of these possibilities with a number of actual case histories.

  19. Troposcatter at the KU Band

    DTIC Science & Technology

    1994-06-01

    Band by Magnus Wennemyr 1 Introduction Appendix Page no. 1 1.1 Introduction I 1.2 Transhorizonal Microwave Propagation n the Troposphere I 1.3 The...1.7.1 Diurnal and Seasonal variations 4 1.7.2 Modes of Propagation 5 1.8 Conclusions 5 2 Effect of the Troposphere on Microwave Propagation 6 2.1...allowing for transhorizonal communication in the microwave ranges. This study tests the viability of using the higher frequency ranges (the test

  20. Follow-up investigations of GPHS motion during heat pulse intervals of reentries from gravity-assist trajectories

    SciTech Connect

    Sharbaugh, R.C.

    1992-03-23

    Motion studies of the General Purpose Heat Source Module, GPHS, which were conducted in the heat pulse intervals associated with entries from earth gravity assist trajectories. The APL six-degree-of-freedom reentry program designated TMAGRA6C was used. The objectives of the studies were to (1) determine whether the GPHS module entering the earth's atmosphere from an earth-gravity-assist trajectory has a preferred orientation during the heat pulse of reentry, (2) determine the effect of magnus force on the roll rate and angle of attack of the GPHS during an EGA entry, (3) determine the effect of the magnitude of pitch and roll damping on the GPHS motion.

  1. Exploring the Scope of Controlling Quantum Phenomena

    DTIC Science & Technology

    2012-12-12

    known, then HE‐OD can also identify the transition amplitudes of the various  Dyson  expansion  orders contributing to the controlled dynamics. The...robust implementation of a target gate. Comparison of these conditions with those obtained from the Magnus expansion and  Dyson  series shows that

  2. International sexual reform and sexology in Europe, 1897-1933.

    PubMed

    Matte, Nicholas

    2005-01-01

    This paper looks at the relationship of sex reformers and sexology to social reform in Europe in the 20th century prior to the outbreak of World War I. It considers a variety of emerging sexual classification systems and national reform efforts, with special attention to Magnus Hirschfeld and the Institute for Sexual Science in Berlin, which was destroyed by the Nazis in 1933. It argues that during this time period the international connections between individual reformers and sexologists developed into a transnational network that was able, to a certain extent, to protect and encourage the rights of sexual minorities both within and beyond national borders.

  3. Good result after surgical treatment of Pellegrini-Stieda syndrome.

    PubMed

    Theivendran, Kanthan; Lever, Caroline J; Hart, William J

    2009-10-01

    Ossification of the femoral attachment of the medial collateral ligament (MCL) of the knee with associated pain and restricted movements is rare and is characteristic of the Pellegrini-Stieda (PS) syndrome. Although in mild cases conservative treatment is often successful, patients with more significant bone formation and persistent symptoms require surgical excision. We describe a case of PS syndrome with a description of the surgical technique consisting of excision of the bony lesion and reconstruction of the MCL by using the adductor magnus tendon.

  4. Toluene alters p75NTR expression in the rat brainstem.

    PubMed

    Pascual, Jesús; Morón, Lena; Zárate, Jon; Gutiérrez, Arantza; Churruca, Itziar; Echevarría, Enrique

    2004-01-01

    Toluene is a neurotoxic organic solvent widely used in industry. Acute toluene administration in rats induced a significant increase in the numbers of neural cells immunostained for p75NTR in several brainstem regions, such as the raphe magnus and the nucleus of the solitary tract, as well as in the lateral reticular, gigantocellular, vestibular and ventral cochlear nuclei, without any in the facial and spinal trigeminal nuclei and the dorsal horn of the spinal cord. These data suggest that p75NTR could be involved in toluene-induced neurotoxic efffects in the rat brainstem.

  5. Neurophysiology of temperature regulation: problems and perspectives.

    PubMed

    Hellon, R F

    1981-12-01

    The neuronal basis of thermal regulation has been intensively studied. Certain neurons in the hypothalamus and elsewhere are extremely sensitive to changes in local and/or external temperature. Recent in vitro work indicates that membrane potentials rather than synaptic events may be the basis of the local sensitivity. Other central sites outside the central nervous system are also now being recognized as sources of thermal information to the thermoregulatory system. The skin thermal input relays to the nucleus raphe magnus and probably passes from there to the hypothalamus. There is still much uncertainty about how and when the skin and deep thermal receptors provide input to the temperature controller.

  6. Analysis of NMR self-diffusion measurements by a density matrix calculation

    NASA Astrophysics Data System (ADS)

    Stepišnik, J.

    1981-04-01

    The density matrix formalism with the Magnus expansion of the time evolution operator is used to study the nmr response in a pulsed magnetic field gradient (mfg) spin-echo experiment. The results show that the spin-echo cannot only measure the self-diffusion coefficient but can determine the spectrum of the single-particle velocity autocorrelation function as well. The proper combination of rf and mfg pulse sequences are proposed for measuring self-diffusion in spin systems with strong dipolar coupling where the classical method fails.

  7. Numerical Predictions of Static-Pressure-Error Corrections for a Modified T-38C Aircraft

    DTIC Science & Technology

    2014-12-15

    pc = pressure correction sic = static indicated corrected ∞ = freestream ⊥ = wall normal I. Introduction T HE fleet of T-38C aircraft at the U.S. Air...but the more modern work of Latif et al. [11] demonstrated that compensated Pitot-static probes can be simulated accurately for subsonic and...Cosmic Gas Dynamics,” Astronomy and Astrophysics , Vol. 108, No. 1, 1982, pp. 76–84. [26] Magnus, R., andYoshihara,H., “Inviscid Transonic FlowoverAirfoils

  8. Testing the Accuracy of a Projectile Motion Apparatus

    NASA Astrophysics Data System (ADS)

    Henderson, Bret; Martell, Eric

    2013-03-01

    The purpose of this research is to predict where a ball would land given initial velocity, angular velocity, and atmospheric conditions. A spinning spherical object flying through air is affected by gravity, quadratic drag forces, and the Magnus force. Mathematica was used to numerically solve predictions for the equations of motion. These predictions were compared with experimental data gathered by launching tennis balls, baseballs, and/or soccer balls from a machine we designed to propel the balls with a pre-determined initial velocity and initial angular velocity.

  9. Synthese De Diols Copolyesters (Synthesis of Copolyester Diols)

    DTIC Science & Technology

    1979-05-01

    complate de l’acide. On 6vapora les maonomeres r ~ siduels par chauffage sous pressiorl r ~duite. On d~termine le contenu en acide .Esiduel, la...trois monom ~ res , d’un 6ther cyclique, d’un. anhydride de diacide et do l’c-caprolactone. Ces pr6polymares possadent diff6rents substituents is long...Polyuxethane Foams from Lactone Monomer ", U.K. Energy Authority, At Weapons Res . Estab.,. Rept AWRE 0-93-64, 1964. S. Magnus, G., "Poly-e-Caprolactone

  10. Vortex motion in YBCO thin films

    NASA Astrophysics Data System (ADS)

    Shapiro, V.; Verdyan, A.; Lapsker, I.; Azoulay, J.

    1999-09-01

    Hall resistivity measurements as function of temperature in the vicinity of Tc were carried out on a thin films YBCO superconductors. A sign reversal of Hall voltage with external magnetic field applied along c axis have been observed upon crossing Tc. Hall voltage in the mixed state was found to be insensitive to the external magnetic field inversion. These effects are discussed and explained in terms of vortex motion under the influence of Magnus force balanced by large damping force. It is argued that in this model the flux-line velocity has component opposite to the superfluid current direction thus yielding a negative Hall voltage.

  11. Effects of time ordering in quantum nonlinear optics

    NASA Astrophysics Data System (ADS)

    Quesada, Nicolás; Sipe, J. E.

    2014-12-01

    We study time-ordering corrections to the description of spontaneous parametric down-conversion (SPDC), four-wave mixing (SFWM), and frequency conversion using the Magnus expansion. Analytic approximations to the evolution operator that are unitary are obtained. They are Gaussian preserving, and allow us to understand order-by-order the effects of time ordering. We show that the corrections due to time ordering vanish exactly if the phase-matching function is sufficiently broad. The calculation of the effects of time ordering on the joint spectral amplitude of the photons generated in SPDC and SFWM are reduced to quadrature.

  12. Unfolding of Vortices into Topological Stripes in a Multiferroic Material

    NASA Astrophysics Data System (ADS)

    Wang, X.; Mostovoy, M.; Han, M. G.; Horibe, Y.; Aoki, T.; Zhu, Y.; Cheong, S.-W.

    2014-06-01

    Multiferroic hexagonal RMnO3 (R =rare earths) crystals exhibit dense networks of vortex lines at which six domain walls merge. While the domain walls can be readily moved with an applied electric field, the vortex cores so far have been impossible to control. Our experiments demonstrate that shear strain induces a Magnus-type force pulling vortices and antivortices in opposite directions and unfolding them into a topological stripe domain state. We discuss the analogy between this effect and the current-driven dynamics of vortices in superconductors and superfluids.

  13. Second-order shaped pulsed for solid-state quantum computation

    SciTech Connect

    Sengupta, Pinaki

    2008-01-01

    We present the construction and detailed analysis of highly optimized self-refocusing pulse shapes for several rotation angles. We characterize the constructed pulses by the coefficients appearing in the Magnus expansion up to second order. This allows a semianalytical analysis of the performance of the constructed shapes in sequences and composite pulses by computing the corresponding leading-order error operators. Higher orders can be analyzed with the numerical technique suggested by us previously. We illustrate the technique by analyzing several composite pulses designed to protect against pulse amplitude errors, and on decoupling sequences for potentially long chains of qubits with on-site and nearest-neighbor couplings.

  14. Force balance on two-dimensional superconductors with a single moving vortex

    NASA Astrophysics Data System (ADS)

    Chung, Chun Kit; Arahata, Emiko; Kato, Yusuke

    2014-03-01

    We study forces on two-dimensional superconductors with a single moving vortex based on a recent fully self-consistent calculation of DC conductivity in an s-wave superconductor (E. Arahata and Y. Kato, arXiv:1310.0566). By considering momentum balance of the whole liquid, we attempt to identify various contributions to the total transverse force on the vortex. This provides an estimation of the effective Magnus force based on the quasiclassical theory generalized by Kita [T. Kita, Phys. Rev. B, 64, 054503 (2001)], which allows for the Hall effect in vortex states.

  15. Survival of Rydberg atoms in intense laser fields and the role of nondipole effects

    NASA Astrophysics Data System (ADS)

    Klaiber, Michael; Dimitrovski, Darko

    2015-02-01

    We consider the interaction of Rydberg atoms with strong infrared laser pulses using an approach based on the Magnus expansion of the time evolution operator. First-order corrections beyond the electric dipole approximation are also included in the theory. We illustrate the dynamics of the interaction at the parameters of the experiment [Eichmann et al., Phys. Rev. Lett. 110, 203002 (2013), 10.1103/PhysRevLett.110.203002]. It emerges that the depletion of Rydberg atoms in this regime comes predominantly from the nondipole effects.

  16. STS-112 crew in front of Launch Pad 39B before launch

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. - Members of the STS-112 crew pose in front of Launch Pad 39B during a tour of Kennedy Space Center prior to launch. From left, they are Mission Specialist Sandra H. Magnus, Commander Jeffrey S. Ashby, Pilot Pamela Ann Melroy, a nd Mission Specialists David A. Wolf, Fyodor N. Yurchikhin of the Russian Space Agency, and Piers J. Sellers. The launch of Space Shuttle Atlantis was postponed today to no earlier than Thursday, Oct. 3, while weather forecasters and the mission managemen t team assess the possible effect Hurricane Lili may have on the Mission Control Center located at the Lyndon B. Johnson Space Center in Houston, Texas.

  17. Hydrodynamic Aspects of the Toms Effect

    NASA Astrophysics Data System (ADS)

    Strel‧nikova, S. A.; Tkachenko, G. V.; Uryukov, B. A.

    2015-11-01

    The physicomathematical model of migration of polymers in a liquid turbulent flow in a pipe is based on a comparison of forces transverse to the motion of the mainstream flow: the Saffman, Magnus, and turbophoresis forces. It has been shown that the polymer particles are grouped near a certain boundary within the limits of the boundary layer. On this basis, the authors have made assumptions on the mechanism of suppression of turbulent pulsations and decrease in the viscous friction near the wall, which makes up the Toms effect. The proposed model satisfies, at least, qualitatively, various actually observed manifestations of the effect.

  18. STS-112 Pilot Melroy inspects cables prior to launch

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. - STS-112 Pilot Pamela Ann Melroy (left) conducts a last-minute inspection of some cables inside Space Shuttle Atlantis at Launch Pad 39B prior to the launch of her mission. The STS-112 crew also includes Commander Jeffrey S. Ashby and Mission Specialists David A. Wolf, Sandra H. Magnus, Piers J. Sellers, and Fyodor N. Yurchikhin of the Russian Space Agency. Launch of the mission was postponed today to no earlier than Thursday, Oct. 3, while weather forecasters and the mission management team assess the possible effect Hurricane Lili may have on the Mission Control Center located at the Lyndon B. Johnson Space Center in Houston, Texas.

  19. Improving the In-Medium Similarity Renormalization Group via approximate inclusion of three-body effects

    NASA Astrophysics Data System (ADS)

    Morris, Titus; Bogner, Scott

    2016-09-01

    The In-Medium Similarity Renormalization Group (IM-SRG) has been applied successfully to the ground state of closed shell finite nuclei. Recent work has extended its ability to target excited states of these closed shell systems via equation of motion methods, and also complete spectra of the whole SD shell via effective shell model interactions. A recent alternative method for solving of the IM-SRG equations, based on the Magnus expansion, not only provides a computationally feasible route to producing observables, but also allows for approximate handling of induced three-body forces. Promising results for several systems, including finite nuclei, will be presented and discussed.

  20. Skyrmionic spin Seebeck effect via dissipative thermomagnonic torques

    NASA Astrophysics Data System (ADS)

    Kovalev, Alexey A.

    2014-06-01

    We derive thermomagnonic torque and its "β-type" dissipative correction from the stochastic Landau-Lifshitz-Gilbert equation. The β-type dissipative correction describes viscous coupling between magnetic dynamics and magnonic current and it stems from spin mistracking of the magnetic order. We show that thermomagnonic torque is important for describing temperature gradient induced motion of skyrmions in helical magnets while dissipative correction plays an essential role in generating transverse Magnus force. We propose to detect such skyrmionic motion by employing the transverse spin Seebeck effect geometry.

  1. Dynamics of bubbles in a two-component Bose-Einstein condensate

    NASA Astrophysics Data System (ADS)

    Sasaki, Kazuki; Suzuki, Naoya; Saito, Hiroki

    2011-03-01

    The dynamics of a phase-separated two-component Bose-Einstein condensate are investigated, in which a bubble of one component moves through the other component. Numerical simulations of the Gross-Pitaevskii equation reveal a variety of dynamics associated with the creation of quantized vortices. In two dimensions, a circular bubble deforms into an ellipse and splits into fragments with vortices, which undergo the Magnus effect. The Bénard-von Kármán vortex street is also generated. In three dimensions, a spherical bubble deforms into toruses with vortex rings. When two rings are formed, they exhibit leapfrogging dynamics.

  2. Improving the In-Medium Similarity Renormalization Group via approximate inclusion of three-body effects

    NASA Astrophysics Data System (ADS)

    Morris, Titus; Bogner, Scott

    2015-10-01

    The In-Medium Similarity Renormalization Group (IM-SRG) has been applied successfully not only to several closed shell finite nuclei, but has recently been used to produce effective shell model interactions that are competitive with phenomenological interactions in the SD shell. A recent alternative method for solving of the IM-SRG equations, called the Magnus expansion, not only provides a computationally feasible route to producing observables, but also allows for approximate handling of induced three-body forces. Promising results for several systems, including finite nuclei, will be presented and discussed.

  3. STS-112 Flight Day 7 Highlights

    NASA Technical Reports Server (NTRS)

    2002-01-01

    On this seventh day of STS-112 mission members of the crew (Commander Jeff Ashby; Pilot Pam Melroy; Mission Specialist Sandy Magnus, Piers Sellers, Dave Wolf, and Fyodor Yurchikhin) along with the Expedition Five crew (Commander Valery Korzun; Flight Engineer Peggy Whitson, and Sergei Treschev) are seen answering questions during the mission's press interview and photo opportunity. They answered various questions regarding the mission's objectives, the onboard science experiments, the extravehicular activities (EVAs) and the effects of living in space. Shots of the test deployment of the S1 truss radiator and Canadarm rotor joint are also shown.

  4. Dynamics of bubbles in a two-component Bose-Einstein condensate

    SciTech Connect

    Sasaki, Kazuki; Suzuki, Naoya; Saito, Hiroki

    2011-03-15

    The dynamics of a phase-separated two-component Bose-Einstein condensate are investigated, in which a bubble of one component moves through the other component. Numerical simulations of the Gross-Pitaevskii equation reveal a variety of dynamics associated with the creation of quantized vortices. In two dimensions, a circular bubble deforms into an ellipse and splits into fragments with vortices, which undergo the Magnus effect. The Benard-von Karman vortex street is also generated. In three dimensions, a spherical bubble deforms into toruses with vortex rings. When two rings are formed, they exhibit leapfrogging dynamics.

  5. Cycloid motions of grains in a dust plasma

    NASA Astrophysics Data System (ADS)

    Yong-Liang, Zhang; Fan, Feng; Fu-Cheng, Liu; Li-Fang, Dong; Ya-Feng, He

    2016-02-01

    Hypocycloid and epicycloid motions of irregular grains (pine pollen) are observed for the first time in a dust plasma in a two-dimensional (2D) horizontal plane. These cycloid motions can be regarded as a combination of a primary circle and a secondary circle. An inverse Magnus force originating from the spin of the irregular grain gives rise to the primary circle. Radial confinement resulting from the electrostatic force and the ion drag force, together with inverse Magnus force, plays an important role in the formation of the secondary circle. In addition, the cyclotron radius is seen to change periodically during the cycloid motion. Force analysis and comparison experiments have shown that the cycloid motions are distinctive features of an irregular grain immersed in a plasma. Project supported by the National Natural Science Foundation of China (Grant Nos. 11205044 and 11405042), the Natural Science Foundation of Hebei Province, China (Grant Nos. A2011201006 and A2012201015), the Research Foundation of Education Bureau of Hebei Province, China (Grant No. Y2012009), the Program for Young Principal Investigators of Hebei Province, and the Midwest Universities Comprehensive Strength Promotion Project.

  6. [Allelopathy of aqueous extract from Ligularia virgaurea, a dominant weed in psychro-grassland, on pasture plants].

    PubMed

    Ma, Ruijun; Wang, Mingli; Zhao, Kun; Guo, Shoujun; Zhao, Qingfang; Sun, Kun

    2006-05-01

    Ligularia virgaurea is a noxious weed widely distributed in the alpine grassland of east Qinghai-Tibet Plateau of China. This paper studied the allelopathy of its aqueous extract on the pasture plants Festuca sinensis, Bromus magnus, Elymus nutans, Poa annua, and F. ovina in the region. The mean response index (RI) values of the pasture plants were calculated, and used to quantitatively assess the allelopathic sensitivity of the receptors at three levels, i. e., growth items, development stages, and species. Corresponding values of the weed were also treated in similar way to assess the allelopathic potential of the donor. The results showed that the allelopathic sensitivity was in the order of P. annua > B. magnus > F. sinensis > F. ovina > E. nutans. Both the seed germination and the seedling growth of test pasture plants were inhibited at species level, suggesting that rain eluviation was one of the means by which the weed released allelochemicals. The aqueous extracts from L. virgaurea root and leaf had a significant inhibitory effect at species level, and the effect of root extract was stronger than that of leaf extract, suggesting the competition among species on the underground resources in natural grassland. Allelopathy played an important role in L. virgaurea invasion, and might be responsible to the formation of mono-dominant community and the degeneration of grassland.

  7. Systematic improvements of ab-initio in-medium similarity renormalization group calculations

    NASA Astrophysics Data System (ADS)

    Morris, Titus Dan

    The In-Medium Similarity Renormalization Group (IM-SRG) is an ab initio many-body method that has enjoyed increasing prominence in nuclear theory, due to its soft polynomial scaling with system size, and the flexibility to target ground and excited states of both closed- and open-shell systems. Despite many successful applications of the IM-SRG to microscopic calculations of medium-mass nuclei in recent years, the conventional formulation of the method suffers a number of limitations. Key amongst these are i) large memory demands that limit calculations in heavier systems and render the calculation of observables besides energy spectra extremely difficult, and ii) the lack of a computationally feasible sequence of improved approximations that converge to the exact solution in the appropriate limit, thereby verifying that the IM-SRG is systematically improvable. In this thesis, I present a novel formulation of the IM-SRG based on the Magnus expansion. I will show that this improved formulation, guided by intuition gleaned from a diagrammatic analysis of the perturbative content of different truncations and parallels with coupled-cluster theory, allows one to bypass the computational limitations of traditional implementations, and provides computationally viable approximations that go beyond the truncations used to date. The effectiveness of the new Magnus formulation is illustrated for several many-nucleon and many-electron systems.

  8. STS-112 Flight Day 1 Highlights

    NASA Technical Reports Server (NTRS)

    2002-01-01

    On the first day of STS-112 the crew (Commander Jeff Ashby, Pilot Pam Melroy and Mission Specialists Sandy Magnus, Piers Sellers, David Wolf and Fyodor Yurchikhin) are shown preparing for launch at Kennedy Space Center, being transported to the Space Shuttle Atlantis at its launch pad, and being seated in the Orbiter. During the launch, the External Tank (ET) camera, mounted to the top of Atlantis's ET and aimed downward) will provide never before seen footage of the shuttle during lift-off. Following the final countdown and liftoff, the ET camera provides footage as Atlantis quickly leaves the Earth behind, at speeds over 2,800 miles per hour. Following orbital insertion, the shuttle's payload bay doors are shown opening in footage provided by a payload bay camera. Sellers and Magnus narrate their thoughts during a replay of the initial launch sequence, shortly after entering orbit. Following the tape, they are shown in the crewcabin with the rest of the crew, and they each share brief thoughts.

  9. The distribution and morphological characteristics of serotonergic cells in the brain of monotremes.

    PubMed

    Manger, P R; Fahringer, H M; Pettigrew, J D; Siegel, J M

    2002-01-01

    The distribution and cellular morphology of serotonergic neurons in the brain of two species of monotremes are described. Three clusters of serotonergic neurons were found: a hypothalamic cluster, a cluster in the rostral brainstem and a cluster in the caudal brainstem. Those in the hypothalamus consisted of two groups, the periventricular hypothalamic organ and the infundibular recess, that were intimately associated with the ependymal wall of the third ventricle. Within the rostral brainstem cluster, three distinct divisions were found: the dorsal raphe nucleus (with four subdivisions), the median raphe nucleus and the cells of the supralemniscal region. The dorsal raphe was within and adjacent to the periaqueductal gray matter, the median raphe was associated with the midline ventral to the dorsal raphe, and the cells of the supralemniscal region were in the tegmentum lateral to the median raphe and ventral to the dorsal raphe. The caudal cluster consisted of three divisions: the raphe obscurus nucleus, the raphe pallidus nucleus and the raphe magnus nucleus. The raphe obscurus nucleus was associated with the dorsal midline at the caudal-most part of the medulla oblongata. The raphe pallidus nucleus was found at the ventral midline of the medulla around the inferior olive. Raphe magnus was associated with the midline of the medulla and was found rostral to both the raphe obscurus and raphe pallidus. The results of our study are compared in an evolutionary context with those reported for other mammals and reptiles.

  10. Radial transport processes as a precursor to particle deposition in drinking water distribution systems.

    PubMed

    van Thienen, P; Vreeburg, J H G; Blokker, E J M

    2011-02-01

    Various particle transport mechanisms play a role in the build-up of discoloration potential in drinking water distribution networks. In order to enhance our understanding of and ability to predict this build-up, it is essential to recognize and understand their role. Gravitational settling with drag has primarily been considered in this context. However, since flow in water distribution pipes is nearly always in the turbulent regime, turbulent processes should be considered also. In addition to these, single particle effects and forces may affect radial particle transport. In this work, we present an application of a previously published turbulent particle deposition theory to conditions relevant for drinking water distribution systems. We predict quantitatively under which conditions turbophoresis, including the virtual mass effect, the Saffman lift force, and the Magnus force may contribute significantly to sediment transport in radial direction and compare these results to experimental observations. The contribution of turbophoresis is mostly limited to large particles (>50 μm) in transport mains, and not expected to play a major role in distribution mains. The Saffman lift force may enhance this process to some degree. The Magnus force is not expected to play any significant role in drinking water distribution systems.

  11. STS-112 Crew exit O&C building before launch

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- The STS-112 crew eagerly exit the Operations and Checkout Building for their ride to Launch Pad 39B and the launch scheduled 3:46 p.m. EDT. Leading the way are Pilot Pamela Melroy and Commander Jeffrey Ashby. In the second row are Mission Specialists David Wolf (left) and Sandra Magnus. Behind them are Mission Specialists Fyodor Yurchikhin and Piers Sellers. Sellers, Magnus and Yurchikhin are making their first Shuttle flights. STS-112 is the 15th assembly flight to the International Space Station, carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts. On the 11-day mission, three spacewalks are planned to attach the S1 truss to the Station. [Photo courtesy of Scott Andrews

  12. STS-112 crew walks out of O&C building before launch

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- The STS-112 crew wave to spectators as they exit the Operations and Checkout Building for their ride to Launch Pad 39B and the launch scheduled 3:46 p.m. EDT. Leading the way are Pilot Pamela Melroy and Commander Jeffrey Ashby. In the second row are Mission Specialists David Wolf (left) and Sandra Magnus. Behind them are Mission Specialists Fyodor Yurchikhin and Piers Sellers. Sellers, Magnus and Yurchikhin are making their first Shuttle flights. STS-112 is the 15th assembly flight to the International Space Station, carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts. On the 11-day mission, three spacewalks are planned to attach the S1 truss to the Station.

  13. CYTOCHEMICAL LOCALIZATION OF TWO GLYCOLYTIC DEHYDROGENASES IN WHITE SKELETAL MUSCLE

    PubMed Central

    Fahimi, H. Dariush; Karnovsky, Morris J.

    1966-01-01

    The cytochemical localization, by conventional methods, of lactate and glyceraldehyde-3-phosphate dehydrogenases is limited, firstly, by the solubility of these enzymes in aqueous media and, secondly, by the dependence of the final electron flow from reduced nicotinamide-adenine dinucleotide (NADH) to the tetrazolium on tissue diaphorase activity: localization is therefore that of the diaphorase, which in rabbit adductor magnus is mitochondrial. NADH has been found to have great affinity to bind in the sarcoplasmic reticulum, and, therefore, if it is generated freely in the incubation media containing 2,2',5,5'-tetra-p-nitrophenyl-3,3'-(3,3'-dimethoxy-4,4'-phenylene)-ditetrazolium chloride (TNBT) and N-methyl phenazonium methyl sulfate (PMS), it can bind there and cause a false staining. Since such a production of NADH can readily occur in the incubation media for glycolytic dehydrogenases due to diffusion of these soluble enzymes from tissue sections, the prevention of enzyme solubilization is extremely important. Fixation in formaldehyde prevented such enzyme diffusion, while at the same time sufficient activity persisted to allow for adequate staining. The incubation media contained PMS, so that the staining system was largely independent of tissue diaphorase activity. Application of these methods to adductor magnus of rabbit revealed by light microscopy, for both enzymes, a fine network which was shown by electron microscopy to represent staining of the sarcoplasmic reticulum. Mitochondria also reacted. These findings add further support for the notion that the sarcoplasmic reticulum is probably involved in glycolytic activity. PMID:4288329

  14. Topological dynamics and current-induced motion in a skyrmion lattice

    NASA Astrophysics Data System (ADS)

    Martinez, J. C.; Jalil, M. B. A.

    2016-03-01

    We study the Thiele equation for current-induced motion in a skyrmion lattice through two soluble models of the pinning potential. Comprised by a Magnus term, a dissipative term and a pinning force, Thiele’s equation resembles Newton’s law but in virtue of the topological character to the first, it differs significantly from Newtonian mechanics and because the Magnus force is dominant, unlike its mechanical counterpart—the Coriolis force—skyrmion trajectories do not necessarily have mechanical counterparts. This is important if we are to understand skyrmion dynamics and tap into its potential for data-storage technology. We identify a pinning threshold velocity for the one-dimensional pinning potential and for a two-dimensional attractive potential we find a pinning point and the skyrmion trajectories toward that point are spirals whose frequency (compare Kepler’s second law) and amplitude-decay depend only on the Gilbert constant and potential at the pinning point. Other scenarios, e.g. other choices of initial spin velocity, a repulsive potential, etc are also investigated.

  15. [The fake lady on trial: transvestitism in psychiatry and the sexual sciences, or the regulation of public dress-code].

    PubMed

    Herrn, Rainer

    2014-01-01

    With the publication of Carl Westphal's "die conträre Sexualempfindung" or "the Contrary Sexual Feeling" (1870), non-conform sexual/gender behavior, such as wearing clothing from the opposite gender, fell within psychiatry's field of activity; psychiatrists cooperated with law enforcement to maintain the public ordering of the sexes. On the basis of the Charité's medical records of a male patient, reported to have publically appeared in women's clothing and thereby making headlines in 1910 as the 'fake lady', the positions of psychiatrist Theodor Ziehen and sexual scientist Magnus Hirschfeld stand in contrast to one another--a development, which affected their forensic argumentation. As Hirschfeld had, in the same year 1910, introduced the concept of transvestitism to describe this very phenomenon, a transfer of competing interpretations out of sexual science and into psychiatry can be studied. The circulation of Magnus Hirschfeld's questionnaire to the vita sexualis allows for an investigation of the effects of such on the collective, biographical narration of sexual minorities, as well as on diagnostic capacity in psychiatry, in reference to transvestitism. An analysis of press-reports on the case and trials of the 'fake lady' approaches the question, how non-conform sexual behavior was to be recognized or identified in public and, for the sake of prevention, how it was explained. Such an analysis also investigates the role of the press in the popularization of Hirschfield's transvestitism concept.

  16. Spin-Orbit Torques and Anisotropic Magnetization Damping in Skyrmion Crystals

    NASA Astrophysics Data System (ADS)

    Hals, Kjetil; Brataas, Arne

    2014-03-01

    We theoretically study the effects of reactive and dissipative homogeneous spin-orbit torques and anisotropic damping on the current-driven skyrmion dynamics in cubic chiral magnets. Our results demonstrate that spin-orbit torques play a significant role in the current-induced skyrmion velocity. The dissipative spin-orbit torque generates a relativistic Magnus force on the skyrmions, whereas the reactive spin-orbit torque yields a correction to both the drift velocity along the current direction and the transverse velocity associated with the Magnus force. The spin-orbit torque corrections to the velocity scale linearly with the skyrmion size, which is inversely proportional to the spin-orbit coupling. Consequently, the reactive spin-orbit torque correction can be the same order of magnitude as the non-relativistic contribution. More importantly, the dissipative spin-orbit torque can be the dominant force that causes a deflected motion of the skyrmions if the torque exhibits a linear or quadratic relationship with the spin-orbit coupling. In addition, we demonstrate that the skyrmion velocity is determined by anisotropic magnetization damping parameters governed by the skyrmion size.

  17. Spin-orbit torques and anisotropic magnetization damping in skyrmion crystals

    NASA Astrophysics Data System (ADS)

    Hals, Kjetil M. D.; Brataas, Arne

    2014-02-01

    The length scale of the magnetization gradients in chiral magnets is determined by the relativistic Dzyaloshinskii-Moriya interaction. Thus, even conventional spin-transfer torques are controlled by the relativistic spin-orbit coupling in these systems, and additional relativistic corrections to the current-induced torques and magnetization damping become important for a complete understanding of the current-driven magnetization dynamics. We theoretically study the effects of reactive and dissipative homogeneous spin-orbit torques and anisotropic damping on the current-driven skyrmion dynamics in cubic chiral magnets. Our results demonstrate that spin-orbit torques play a significant role in the current-induced skyrmion velocity. The dissipative spin-orbit torque generates a relativistic Magnus force on the skyrmions, whereas the reactive spin-orbit torque yields a correction to both the drift velocity along the current direction and the transverse velocity associated with the Magnus force. The spin-orbit torque corrections to the velocity scale linearly with the skyrmion size, which is inversely proportional to the spin-orbit coupling. Consequently, the reactive spin-orbit torque correction can be the same order of magnitude as the nonrelativistic contribution. More importantly, the dissipative spin-orbit torque can be the dominant force that causes a deflected motion of the skyrmions if the torque exhibits a linear or quadratic relationship with the spin-orbit coupling. In addition, we demonstrate that the skyrmion velocity is determined by anisotropic magnetization damping parameters governed by the skyrmion size.

  18. Interaction of vortices with ultrasound and the acoustic Faraday effect in type-II superconductors

    SciTech Connect

    Dominguez, D.; Bulaevskii, L.; Ivlev, B. |; Maley, M.; Bishop, A.R.

    1996-03-01

    We study the interaction of sound waves with vortices in type-II superconductors, taking into account pinning and electrodynamic forces between vortices and crystal displacements. We propose ultrasound techniques as a method for obtaining information about vortex dynamics. This is particularly appropiate at low temperatures where transport measurements are ineffective. The changes in sound velocity and attenuation due to vortices, can provide information on the elastic constants of the vortex system and on vortex dissipation, respectively. At low temperatures the Magnus force acting on vortices leads to the {ital acoustic} {ital Faraday} {ital effect}: there is a rotation of the polarization plane of tranverse sound waves propagating along the magnetic field. This effect is linear in the Magnus force and magnetic field in crystals with equivalent {ital a} and {ital b} axes for a field parallel to the {ital c} axis. We discuss how this effect can be measured by means of either pulse-echo techniques or standing sound waves. Also, we show that an ac electromagnetic field acting on the vortex system can generate ultrasound. We calculate the amplitude of the generated sound waves in the linear regime and compare with recent experiments. {copyright} {ital 1996 The American Physical Society.}

  19. Aerodynamics in the classroom and at the ball park

    NASA Astrophysics Data System (ADS)

    Cross, Rod

    2012-04-01

    Experiments suitable for classroom projects or demonstrations are described concerning the aerodynamics of polystyrene balls. A light ball with sufficient backspin can curve vertically upward through the air, defying gravity and providing a dramatic visual demonstration of the Magnus effect. A ball projected with backspin can also curve downward with a vertical acceleration greater than that due to gravity if the Magnus force is negative. These effects were investigated by filming the flight of balls projected in an approximately horizontal direction so that the lift and drag forces could be easily measured. The balls were also fitted with artificial raised seams and projected with backspin toward a vertical target in order to measure the sideways deflection over a known horizontal distance. It was found that (a) a ball with a seam on one side can deflect either left or right depending on its launch speed and (b) a ball with a baseball seam can also deflect sideways even when there is no sideways component of the drag or lift forces acting on the ball. Depending on the orientations of the seam and the spin axis, a sideways force on a baseball can arise either if there is rough patch on one side of the ball or if there is a smooth patch. A scuff ball with a rough patch on one side is illegal in baseball. The effect of a smooth patch is a surprising new observation.

  20. Dynamics of antiferromagnetic skyrmion driven by the spin Hall effect

    NASA Astrophysics Data System (ADS)

    Jin, Chendong; Song, Chengkun; Wang, Jianbo; Liu, Qingfang

    2016-10-01

    Magnetic skyrmion moved by the spin-Hall effect is promising for the application of the generation racetrack memories. However, the Magnus force causes a deflected motion of skyrmion, which limits its application. Here, we create an antiferromagnetic skyrmion by injecting a spin-polarized pulse in the nanostripe and investigate the spin Hall effect-induced motion of antiferromagnetic skyrmion by micromagnetic simulations. In contrast to ferromagnetic skyrmion, we find that the antiferromagnetic skyrmion has three evident advantages: (i) the minimum driving current density of antiferromagnetic skyrmion is about two orders smaller than the ferromagnetic skyrmion; (ii) the velocity of the antiferromagnetic skyrmion is about 57 times larger than the ferromagnetic skyrmion driven by the same value of current density; (iii) antiferromagnetic skyrmion can be driven by the spin Hall effect without the influence of Magnus force. In addition, antiferromagnetic skyrmion can move around the pinning sites due to its property of topological protection. Our results present the understanding of antiferromagnetic skyrmion motion driven by the spin Hall effect and may also contribute to the development of antiferromagnetic skyrmion-based racetrack memories.

  1. Activation energy distributions predicted by dispersive kinetic models for nucleation and denucleation: anomalous diffusion resulting from quantization.

    PubMed

    Skrdla, Peter J

    2011-06-23

    The activation energy distributions underpinning the two complementary dispersive kinetic models described by the author in a recent work (Skrdla, P. J. J. Phys. Chem. A 2009, 113, 9329) are derived and investigated. In the case of nucleation rate-limited conversions, which exhibit "acceleratory" sigmoidal transients (a kind of S-shaped stretched exponential conversion profile), an activation energy distribution visually similar to the Maxwell-Boltzmann (M-B) distribution is recovered, consistent with the original derivation of that model. In the case of predominantly "deceleratory" conversions, the activation energy distribution is skewed from normal in the opposite direction. While the "M-B-like" activation energy distribution supports the empirical observation of a rate enhancement as a function of the conversion time in nucleation rate-limited processes, the complementary distribution, with its pronounced low-energy tail, reflects a slow-down in the specific rate as the conversion progresses, consistent with experimentally observed denucleation rate-limited conversions. Activation energy distributions were also plotted for real-world data (Qu, H.; Louhi-Kultanen, M.; Kallas, J. Cryst. Growth Des. 2007, 7, 724), depicting the impact of various additives on the nucleation rate-limited kinetics of the solvent-mediated phase transformation of the crystalline drug carbamazepine. Last, by coupling the author's dispersive kinetic description of the time-dependent activation energy for nucleation to the classical description of the critical nucleus energy provided by the Kelvin equation, an accelerated hopping mechanism for the diffusion of monomers to the growing embryo surface was observed. That hopping mechanism was rationalized by modifying the Einstein-Smoluchowski (E-S) equation to allow it to describe the "supra-brownian" molecular motion thought to lie at the heart of nucleation kinetics.

  2. STS-112 crew with President of Ajara in Georgia (Russia)

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- In the Operations and Checkout Building, Aslan Abashidze (right), President of the Autonomous Republic of Ajara in Georgia (Russia), visits with the STS-112 crew. From left, they are Mission Specialist Piers J. Sellers; Pilot Pamela Ann Melroy; Mission Specialist Fyodor N. Yurchikhin, a cosmonaut with the Russian Space Agency; Mission Specialist Sandra H. Magnus; and CommanderJeffrey S. Ashby. Mission Specialist David A. Wolf, not pictured, is also a member of the crew. The crew is awaiting launch on mission STS-112 to the International Space Station aboard Space Shuttle Atlantis. The launch has been postponed to no earlier than Monday, Oct. 7, so that the Mission Control Center, located at the Lyndon B. Johnson Space Center in Houston, Texas, can be secured and protected from potential storm impacts from Hurricane Lili.

  3. General Transfer-Function Approach to Noise Filtering in Open-Loop Quantum Control

    NASA Astrophysics Data System (ADS)

    Paz-Silva, Gerardo A.; Viola, Lorenza

    2014-12-01

    We present a general transfer-function approach to noise filtering in open-loop Hamiltonian engineering protocols for open quantum systems. We show how to identify a computationally tractable set of fundamental filter functions, out of which arbitrary transfer filter functions may be assembled up to arbitrary high order in principle. Besides avoiding the infinite recursive hierarchy of filter functions that arises in general control scenarios, this fundamental filter-function set suffices to characterize the error suppression capabilities of the control protocol in both the time and the frequency domain. We prove that the resulting notion of filtering order reveals conceptually distinct, albeit complementary, features of the controlled dynamics as compared to the order of error cancellation, traditionally defined in the Magnus sense. Examples and implications are discussed.

  4. STS-112 Atlantis landing at KSC's shuttle landing facility

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. - Its shadow precedes it as Space Shuttle Atlantis drops to the runway at the Shuttle Landing Facility, completing the 4.5-million-mile journey to the International Space Station. Main gear touchdown occurred at 11:43:40 a.m. EDT; nose gear touchdown at 11:43:48 a.m.; and wheel stop at 11:44:35 a.m. Mission elapsed time was 10:19:58:44. Mission STS-112 expanded the size of the Station with the addition of the S1 truss segment. The returning crew of Atlantis are Commander Jeffrey Ashby, Pilot Pamela Melroy, and Mission Specialists David Wolf, Piers Sellers, Sandra Magnus and Fyodor Yurchikhin. This landing is the 60th at KSC in the history of the Shuttle program. .

  5. STS-112 Atlantis landing at KSC's shuttle landing facility

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- Space Shuttle Atlantis casts a needle-shaped shadow as it drops to the runway at the Shuttle Landing Facility, completing the 4.5-million-mile journey to the International Space Station. Main gear touchdown occurred at 11:43:40 a.m. EDT; nose gear touchdown at 11:43:48 a.m.; and wheel stop at 11:44:35 a.m. Mission elapsed time was 10:19:58:44. Mission STS-112 expanded the size of the Station with the addition of the S1 truss segment. The returning crew of Atlantis are Commander Jeffrey Ashby, Pilot Pamela Melroy, and Mission Specialists David Wolf, Piers Sellers, Sandra Magnus and Fyodor Yurchikhin. This landing is the 60th at KSC in the history of the Shuttle program.

  6. Three-loop master integrals for ladder-box diagrams with one massive leg

    NASA Astrophysics Data System (ADS)

    Di Vita, Stefano; Mastrolia, Pierpaolo; Schubert, Ulrich; Yundin, Valery

    2014-09-01

    The three-loop master integrals for ladder-box diagrams with one massive leg are computed from an eighty-five by eighty-five system of differential equations, solved by means of Magnus exponential. The results of the considered box-type integrals, as well as of the tower of vertex- and bubble-type master integrals associated to subtopologies, are given as a Taylor series expansion in the dimensional regulator parameter ɛ = (4 - d)/2. The coefficients of the series are expressed in terms of uniform weight combinations of multiple polylogarithms and transcendental constants up to weight six. The considered integrals enter the next-to-next-to-next-to-leading order virtual corrections to scattering processes like the three-jet production mediated by vector boson decay, V * → jjj, as well as the Higgs plus one-jet production in gluon fusion, pp → Hj.

  7. Vortex annihilation and inverse cascades in two dimensional superfluid turbulence

    NASA Astrophysics Data System (ADS)

    Lucas, Andrew; Chesler, Paul M.

    2015-03-01

    The dynamics of a dilute mixture of vortices and antivortices in a turbulent two-dimensional superfluid at finite temperature is well described by first order Hall-Vinen-Iordanskii equations, or dissipative point vortex dynamics. These equations are governed by a single dimensionless parameter: the ratio of the strength of drag forces to Magnus forces on vortices. When this parameter is small, we demonstrate using numerical simulations that the resulting superfluid enjoys an inverse energy cascade where small scale stirring leads to large scale vortex clustering. We argue analytically and numerically that the vortex annihilation rate in a laminar flow may be parametrically smaller than the rate in a turbulent flow with an inverse cascade. This suggests a new way to detect inverse cascades in experiments on two-dimensional superfluid turbulence using cold atomic gases, where traditional probes of turbulence such as the energy spectrum are not currently accessible.

  8. Long-time Behavior of Isolated Periodically Driven Interacting Lattice Systems

    NASA Astrophysics Data System (ADS)

    D'Alessio, Luca; Rigol, Marcos

    2014-10-01

    We study the dynamics of isolated interacting spin chains that are periodically driven by sudden quenches. Using full exact diagonalization of finite chains, we show that these systems exhibit three distinct regimes. For short driving periods, the Floquet Hamiltonian is well approximated by the time-averaged Hamiltonian, while for long periods, the evolution operator exhibits properties of random matrices of a circular ensemble (CE). In between, there is a crossover regime. Based on a finite-size scaling analysis and analytic arguments, we argue that, for thermodynamically large systems and nonvanishing driving periods, the evolution operator always exhibits properties of the CE of random matrices. Consequently, the Floquet Hamiltonian is a nonlocal Hamiltonian with multispin interaction terms, and the driving leads to the equivalent of an infinite temperature state at long times. These results are connected to the breakdown of the Magnus expansion and are expected to hold beyond the specific lattice model considered.

  9. STS-112 Flight Day 2 Highlights

    NASA Technical Reports Server (NTRS)

    2002-01-01

    On the second flight day of STS-112 (Commander Jeff Ashby, Pilot Pam Melroy and Mission Specialists Sandy Magnus, Piers Sellers, David Wolf and Fyodor Yurchikhin), video footage is shown of the Space Shuttle Atlantis's payload bay, which contains the International Space Station's (ISS) S1 (S-One) truss section, which will be installed on the ISS by Sellers and Wolf during EVAs (extravehicular activities) following Atlantis's docking with the station. Also shown, via a camera on the shuttle's robotic arm, are the three radiators that reside on the truss structure and will provide cooling capability for the entire station. During this flight day, Atlantis passes over Southern California, Nevada, Wyoming, South Dakota, and Minnesota in a track that will eventually bring it over Newfoundland and Labrador.

  10. STS-112 Atlantis landing at KSC's shuttle landing facility

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- Space Shuttle Atlantis kicks up dust as it touches down at the Shuttle Landing Facility, completing the 4.5-million-mile journey to the International Space Station. Main gear touchdown occurred at 11:43:40 a.m. EDT; nose gear touchdown at 11:43:48 a.m.; and wheel stop at 11:44:35 a.m. Mission elapsed time was 10:19:58:44. Mission STS-112 expanded the size of the Station with the addition of the S1 truss segment. The returning crew of Atlantis are Commander Jeffrey Ashby, Pilot Pamela Melroy, and Mission Specialists David Wolf, Piers Sellers, Sandra Magnus and Fyodor Yurchikhin. This landing is the 60th at KSC in the history of the Shuttle program.

  11. High-frequency approximation for periodically driven quantum systems from a Floquet-space perspective

    NASA Astrophysics Data System (ADS)

    Eckardt, André; Anisimovas, Egidijus

    2015-09-01

    We derive a systematic high-frequency expansion for the effective Hamiltonian and the micromotion operator of periodically driven quantum systems. Our approach is based on the block diagonalization of the quasienergy operator in the extended Floquet Hilbert space by means of degenerate perturbation theory. The final results are equivalent to those obtained within a different approach (Rahav et al 2003 Phys. Rev. A 68 013820), (Goldman and Dalibard 2014 Phys. Rev. X 4 031027) and can also be related to the Floquet-Magnus expansion (Casas et al 2001 J. Phys. A 34 3379). We discuss that the dependence on the driving phase, which plagues the latter, can lead to artifactual symmetry breaking. The high-frequency approach is illustrated using the example of a periodically driven Hubbard model. Moreover, we discuss the nature of the approximation and its limitations for systems of many interacting particles.

  12. STS-112 Atlantis landing at KSC's shuttle landing facility

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- Space Shuttle Atlantis approaches the runway at the Shuttle Landing Facility, completing the 4.5-million-mile journey to the International Space Station. Main gear touchdown occurred at 11:43:40 a.m. EDT; nose gear touchdown at 11:43:48 a.m.; and wheel stop at 11:44:35 a.m. Mission elapsed time was 10:19:58:44. Mission STS-112 expanded the size of the Station with the addition of the S1 truss segment. The returning crew of Atlantis are Commander Jeffrey Ashby, Pilot Pamela Melroy, and Mission Specialists David Wolf, Piers Sellers, Sandra Magnus and Fyodor Yurchikhin. This landing is the 60th at KSC in the history of the Shuttle program. .

  13. STS-112 crew leave the crew transport vehicle after landing

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- As the STS-112 crew leaves the crew transport vehicle, they are greeted by mission managers and guests. The crew, from left, are Mission Specialists David Wolf, Fyodor Yurchikhin and Sandra Magnus; Pilot Pamela Melroy; Piers Sellers (talking to Acting Deputy Director JoAnn Morgan) and Commander Jeffrey Ashby (talking to Launch Director Mike Leinbach). Morgan is also Director of External Relations and Business Development. The crew returned to KSC after completing a 4.5-million-mile journey to the International Space Station. Main gear touchdown occurred at 11:43:40 a.m. EDT; nose gear touchdown at 11:43:48 a.m.; and wheel stop at 11:44:35 a.m. Mission elapsed time was 10:19:58:44. Mission STS-112 expanded the size of the Station with the addition of the S1 truss segment. .

  14. Effective theory of vortices in two-dimensional spinless chiral p -wave superfluids

    NASA Astrophysics Data System (ADS)

    Ariad, Daniel; Grosfeld, Eytan; Seradjeh, Babak

    2015-07-01

    We propose a U (1 ) ×Z2 effective gauge theory for vortices in a px+i py superfluid in two dimensions. The combined gauge transformation binds U (1 ) and Z2 defects so that the total transformation remains single-valued and manifestly preserves the particle-hole symmetry of the action. The Z2 gauge field introduces a complete Chern-Simons term in addition to a partial one associated with the U (1 ) gauge field. The theory reproduces the known physics of vortex dynamics such as a Magnus force proportional to the superfluid density. More importantly, it predicts a universal Abelian phase, exp(i π /8 ) , upon the exchange of two vortices. This phase is modified by nonuniversal corrections due to the partial Chern-Simon term, which are nevertheless screened in a charged superfluid at distances that are larger than the penetration depth.

  15. STS-112 Atlantis landing at KSC's shuttle landing facility

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- Its drag chute deployed, Space Shuttle Atlantis slows to a stop after touchdown on Runway 33 at the Shuttle Landing Facility, completing the 4.5-million-mile journey to the International Space Station. Main gear touchdown occurred at 11:43:40 a.m. EDT; nose gear touchdown at 11:43:48 a.m.; and wheel stop at 11:44:35 a.m. Mission elapsed time was 10:19:58:44. Mission STS-112 expanded the size of the Station with the addition of the S1 truss segment. The returning crew of Atlantis are Commander Jeffrey Ashby, Pilot Pamela Melroy, and Mission Specialists David Wolf, Piers Sellers, Sandra Magnus and Fyodor Yurchikhin. This landing is the 60th at KSC in the history of the Shuttle program. .

  16. STS-112 crew in front of Atlantis after landing at KSC

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- After a flawless landing on runway 33 of the Shuttle Landing Facility, the STS-112 crew poses in front of Atlantis. From left are Mission Specialists Piers Sellers and Sandra Magnus, Pilot Pamela Melroy, Commander Jeffrey Ashby, and Mission Specialists David Wolf and Fyodor Yurchikhin, who represents the Russian Space Agency. Main gear touchdown occurred at 11:43:40 a.m. EDT; nose gear touchdown at 11:43:48 a.m.; and wheel stop at 11:44:35 a.m. Mission elapsed time was 10:19:58:44. STS-112 expanded the size of the Station with the addition of the S1 truss segment.

  17. Some Aspects of the Physics of Shooting a Basketball

    NASA Astrophysics Data System (ADS)

    Fontanella, John J.

    2006-12-01

    The flight of a basketball is considered.1 Video analysis of the path and spin for several shots was carried out. It is shown that four forces are required to reproduce the trajectory: gravity, buoyancy, the drag force and the Magnus force. The relative contribution of each force is determined. The model is used to evaluate what it is that good shooters do. For a foul shot, the approach speed (speed when the basketball is just above the rim), launch speed, and launch angle were calculated. It is found that the minimum in the approach speed occurs at a launch angle closer to the experimental values for good shooters than does the minimum in the launch speed. This suggests the hoopothesis that a good shooter strives for the “softest” shot. 1. J. J. Fontanella, The Physics of Basketball, The Johns Hopkins University Press, Baltimore, 2006.

  18. Dynamics of vortices in neutral superfluids with noninteracting phonons

    NASA Astrophysics Data System (ADS)

    Fortin, Jean-Yves

    2001-05-01

    The transverse force on an isolated and moving vortex in a neutral superfluid at rest is evaluated at finite temperature in the case of noninteracting phonons. Using the Thouless, Ao, Niu (TAN) [Phys. Rev. Lett. 76, 3758 (1996)] general theory, we show that the transverse force is exactly equal to the superfluid Magnus force. We extend this theory in the case of a slowly moving vortex on a circular trajectory, and find an additional contribution coming from the centrifugal reaction. This term gives a negative vortex mass due to the phonons and diverges logarithmically at low frequency. The friction force is also evaluated for zero and finite frequencies, and compared with the scattering theory.

  19. On the modification of particle dispersion in isotropic turbulence by free rotation of particle

    NASA Astrophysics Data System (ADS)

    Park, Yongnam; Lee, Changhoon

    2008-11-01

    Effect of a particle's spin is investigated numerically by considering the effect of lift occurring due to difference of rotations of a particle and of fluid such as the Saffman lift and Magnus force. These lift forces have been neglected in many previous works on particle-laden turbulence. The trajectory of particles can be changed by the lift forces, resulting in significant modification of the stochastic characteristics of heavy particles. Probability density functions and autocorrelations are examined of velocity, acceleration of solid particle and acceleration of fluid at the position of solid particle. Changes in velocity statistics are negligible but statistics related with acceleration are a little bit changed by particle's rotation. When a laden particle encounters with coherent structures during the motion, the particle's rotation might significantly affects the motion due to intermittently large fluid acceleration near coherent structures. The result can be used for development of stochastic model for particle dispersion. Detailed physical interpretation will be presented in the meeting.

  20. The aerodynamics of tennis balls-The topspin lob

    NASA Astrophysics Data System (ADS)

    Štěpánek, Antonín

    1988-02-01

    A general description is presented of the calculation of the ballistic trajectory of a flying spinning ball acted on, in addition to the forces of gravity and drag, by the so-called Magnus force. By applying the regression analysis to results of wind-tunnel measurement of the drag and lift coefficients of a spinning ball, a calculation of the nonlinear differential equation of the hodograph was carried out by means of the Runge-Kutta method. The theoretical results that can be used to calculate the ballistic trajectories for any ball game were applied to one of the most difficult and most interesting tennis strokes, i.e., to the topspin lob. Practical results obtained for various distances are presented in a table as well as in graphical form. UFAJP

  1. How Far Would a Home Run Really Have Gone?

    NASA Astrophysics Data System (ADS)

    Sherwin, W. G.; Cheng, Y. C.; Chunko, J. D.; Eagan, T. P.; Brown, R. W.

    2002-04-01

    A controversial issue in professional baseball arises from attempts to estimate how far home run balls would have traveled if they had not hit some obstruction, such as a scoreboard or bleacher seating. A Runge-Kutta numerical simulation model is developed for baseball trajectories including the effects of velocity-dependent drag forces, velocity-dependent Magnus spin forces (including a model for the decrease of the spin rate over the trajectory), and the wind. The computational model is used to build a numerical catalog for the combination of initial ball speeds and angles that give rise to a set of trajectories that have the same final impact point (e.g., on the scoreboard). The data required by an observer to estimate the actual home run range are discussed. A homerun hit by Mark McGwire against the Cleveland Indians on 30 April 1997 that dented the Jacobs Field scoreboard is analyzed.

  2. Liouville-von Neumann molecular dynamics

    NASA Astrophysics Data System (ADS)

    Jakowski, Jacek; Morokuma, Keiji

    2009-06-01

    We present a novel first principles molecular dynamics scheme, called Liouville-von Neumann molecular dynamics, based on Liouville-von Neumann equation for density matrices propagation and Magnus expansion of the time-evolution operator. The scheme combines formally accurate quantum propagation of electrons represented via density matrices and a classical propagation of nuclei. The method requires a few iterations per each time step where the Fock operator is formed and von Neumann equation is integrated. The algorithm (a) is free of constraint and fictitious parameters, (b) avoids diagonalization of the Fock operator, and (c) can be used in the case of fractional occupation as in metallic systems. The algorithm is very stable, and has a very good conservation of energy even in cases when a good quality conventional Born-Oppenheimer molecular dynamics trajectories is difficult to obtain. Test simulations include initial phase of fullerene formation from gaseous C2 and retinal system.

  3. Model for fast, nonadiabatic collisions between alkali atoms and diatomic molecules

    NASA Astrophysics Data System (ADS)

    Hickman, A. P.

    1980-11-01

    Equations for collisions involving two potential surfaces are presented in the impact parameter approximation. In this approximation, a rectilinear classical trajectory is assumed for the translational motion, leading to a time-dependent Schroedinger's equation for the remaining degrees of freedom. Model potentials are considered for collisions of alkali atoms with diatomic molecules that lead to a particularly simple form of the final equations. Using the Magnus approximation, these equations are solved for parameters chosen to model the process Cs+O2→Cs++O2-, and total cross sections for ion-pair formation are obtained as a function of energy. The results exhibit oscillations that correspond qualitatively to those seen in recent measurements. In addition, the model predicts that the oscillations will become less pronounced as the initial vibrational level of O2 is increased.

  4. Exponential time-dependent perturbation theory in rotationally inelastic scattering

    NASA Astrophysics Data System (ADS)

    Cross, R. J.

    1983-08-01

    An exponential form of time-dependent perturbation theory (the Magnus approximation) is developed for rotationally inelastic scattering. A phase-shift matrix is calculated as an integral in time over the anisotropic part of the potential. The trajectory used for this integral is specified by the diagonal part of the potential matrix and the arithmetic average of the initial and final velocities and the average orbital angular momentum. The exponential of the phase-shift matrix gives the scattering matrix and the various cross sections. A special representation is used where the orbital angular momentum is either treated classically or may be frozen out to yield the orbital sudden approximation. Calculations on Ar+N2 and Ar+TIF show that the theory generally gives very good agreement with accurate calculations, even where the orbital sudden approximation (coupled-states) results are seriously in error.

  5. Passive scalar mixing in vortex rings

    NASA Astrophysics Data System (ADS)

    Sau, Rajes; Mahesh, Krishnan

    2006-11-01

    Direct numerical simulations of passive scalar mixing in vortex rings are performed, with and without crossflow. The simulation results without crossflow agree well with experimental data for `formation number', total circulation, trajectory and entrainment fraction. Scalar profiles, mixedness and volume of scalar carrying fluid are used to quantify mixing, whose characteristics are quite different in the formation and propagation phases of the ring. These results are explained in terms of entrainment by the ring. The simulations with crossflow show that the ring tilts and deforms. When the stroke ratio is greater than formation number, the ring tilts in the direction of the crossflow. On the other hand, when the stroke ratio is less than formation number, the ring tilts in the opposite direction, such that its induced velocity opposes the crossflow. The Magnus effect may be used to provide a simple explanation. The impact of this behavior on mixing will be discussed.

  6. Experimental determination of baseball spin and lift.

    PubMed

    Alaways, L W; Hubbard, M

    2001-05-01

    The aim of this study was to develop a new method for the determination of lift on spinning baseballs. Inertial trajectories of (a) ball surface markers during the first metre of flight and (b) the centre of mass trajectory near home-plate were measured in a pitch using high-speed video. A theoretical model was developed, incorporating aerodynamic Magnus-Robins lift, drag and cross forces, which predicts the centre of mass and marker trajectories. Parameters including initial conditions and aerodynamic coefficients were estimated iteratively by minimizing the error between predicted and measured trajectories. We compare the resulting lift coefficients and spin parameter values with those of previous studies. Lift on four-seam pitches can be as much as three times that of two-seam pitches, although this disparity is reduced for spin parameters greater than 0.4.

  7. Non-Abelian evolution of electromagnetic waves in a weakly anisotropic inhomogeneous medium

    NASA Astrophysics Data System (ADS)

    Bliokh, K. Yu.; Frolov, D. Yu.; Kravtsov, Yu. A.

    2007-05-01

    A theory of electromagnetic wave propagation in a weakly anisotropic smoothly inhomogeneous medium is developed, based on the quantum-mechanical diagonalization procedure applied to Maxwell equations. The equations of motion for the translational (ray) and intrinsic (polarization) degrees of freedom are derived ab initio. The ray equations take into account the optical Magnus effect (spin Hall effect of photons) as well as trajectory variations owing to the medium anisotropy. Polarization evolution is described by the precession equation for the Stokes vector. In the generic case, the evolution of wave turns out to be non-Abelian: it is accompanied by mutual conversion of the normal modes and periodic oscillations of the ray trajectories analogous to electron zitterbewegung. The general theory is applied to examples of wave evolution in media with circular and linear birefringence.

  8. Judging where a ball will go: the case of curved free kicks in football.

    PubMed

    Craig, Cathy M; Berton, Eric; Rao, Guillaume; Fernandez, Laure; Bootsma, Reinoud J

    2006-02-01

    This study examined whether adding spin to a ball in the free kick situation in football affects a professional footballer's perception of the ball's future arrival position. Using a virtual reality set-up, participants observed the flight paths of aerodynamically realistic free kicks with (+/-600 rpm) and without sidespin. With the viewpoint being fixed in the centre of the goal, participants had to judge whether the ball would have ended up in the goal or not. Results show that trajectories influenced by the Magnus force caused by sidespin gave rise to a significant shift in the percentage of goal responses. The resulting acceleration that causes the ball to continually change its heading direction as the trajectory unfolds does not seem to be taken into account by the participants when making goal judgments. We conclude that the visual system is not attuned to such accelerated motion, which may explain why goalkeepers appear to misjudge the future arrival point of such curved free kicks.

  9. International Program and Local Organizing Committees

    NASA Astrophysics Data System (ADS)

    2012-12-01

    International Program Committee Dionisio Bermejo (Spain) Roman Ciurylo (Poland) Elisabeth Dalimier (France) Alexander Devdariani (Russia) Milan S Dimitrijevic (Serbia) Robert Gamache (USA) Marco A Gigosos (Spain) Motoshi Goto (Japan) Magnus Gustafsson (Sweden) Jean-Michel Hartmann (France) Carlos Iglesias (USA) John Kielkopf (USA) John C Lewis (Canada) Valery Lisitsa (Russia) Eugene Oks (USA) Christian G Parigger (USA) Gillian Peach (UK) Adriana Predoi-Cross (Canada) Roland Stamm (Germany) Local Organizing Committee Nikolay G Skvortsov (Chair, St Petersburg State University) Evgenii B Aleksandrov (Ioffe Physico-Technical Institute, St Petersburg) Vadim A Alekseev (Scientific Secretary, St Petersburg State University) Sergey F Boureiko (St.Petersburg State University) Yury N Gnedin (Pulkovo Observatory, St Petersburg) Alexander Z Devdariani (Deputy Chair, St Petersburg State University) Alexander P Kouzov (Deputy Chair, St Petersburg State University) Nikolay A Timofeev (St Petersburg State University)

  10. Yeasts in high Arctic glaciers: the discovery of a new habitat for eukaryotic microorganisms.

    PubMed

    Butinar, Lorena; Spencer-Martins, Isabel; Gunde-Cimerman, Nina

    2007-04-01

    Recently a new habitat for microbial life has been discovered at the base of polythermal glaciers. In ice from these subglacial environments so far only non-photosynthetic bacterial communities were discovered, but no eukaryotic microorganisms. We found high numbers of yeast cells, amounting to a maximum of 4,000 CFU ml(-1) of melt ice, in four different high Arctic glaciers. Twenty-two distinct species were isolated, including two new yeast species. Basidiomycetes predominated, among which Cryptococcus liquefaciens was the dominant species (ca. 90% of total). Other frequently occurring species were Cryptococcus albidus, Cryptococcus magnus, Cryptococcus saitoi and Rhodotorula mucilaginosa. The dominant yeast species were psychrotolerant, halotolerant, freeze-thaw resistant, unable to form mycelium, relatively small-sized and able to utilize a wide range of carbon and nitrogen sources. This is the first report on the presence of yeast populations in subglacial ice.

  11. STS-112 crew on SLF after landing

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- STS-112 Pilot Pamela Melroy (left) and Mission Specialist Sandra Magnus (center) talk to Acting Deputy Director JoAnn Morgan (right) after the crew's return to KSC. A flawless landing of Space Shuttle Atlantis completed a 4.5 -million-mile journey to the International Space Station. Other crew members are Commander Jeffrey Ashby and Mission Specialists David Wolf, Fyodor Yurchikhin and Piers Sellers. Main gear touchdown occurred at 11:43:40 a.m. EDT; nose gear touchdown at 11: 43:48 a.m.; and wheel stop at 11:44:35 a.m. Mission elapsed time was 10:19:58:44. Mission STS-112 expanded the size of the Station with the addition of the S1 truss segment.

  12. STS-112 Atlantis landing at KSC's shuttle landing facility

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. - Space Shuttle Atlantis approaches the runway at the Shuttle Landing Facility, completing the 4.5-million-mile journey to the International Space Station. Main gear touchdown occurred at 11:43:40 a.m. EDT; nose gear touchdown at 11:43:48 a.m.; and wheel stop at 11:44:35 a.m. Mission elapsed time was 10:19:58:44. Mission STS-112 expanded the size of the Station with the addition of the S1 truss segment. The returning crew of Atlantis are Commander Jeffrey Ashby, Pilot Pamela Melroy, and Mission Specialists David Wolf, Piers Sellers, Sandra Magnus and Fyodor Yurchikhin. This landing is the 60th at KSC in the history of the Shuttle program.

  13. Geometrical optics of beams with vortices: Berry phase and orbital angular momentum Hall effect.

    PubMed

    Bliokh, Konstantin Yu

    2006-07-28

    We consider propagation of a paraxial beam carrying the spin angular momentum (polarization) and intrinsic orbital angular momentum (IOAM) in a smoothly inhomogeneous isotropic medium. It is shown that the presence of IOAM can dramatically enhance and rearrange the topological phenomena that previously were considered solely in connection to the polarization of transverse waves. In particular, the appearance of a new type of Berry phase that describes the parallel transport of the beam structure along a curved ray is predicted. We derive the ray equations demonstrating the splitting of beams with different values of IOAM. This is the orbital angular momentum Hall effect, which resembles the Magnus effect for optical vortices. Unlike the spin Hall effect of photons, it can be much larger in magnitude and is inherent to waves of any nature. Experimental means to detect the phenomena are discussed.

  14. Follow-up investigations of GPHS motion during heat pulse intervals of reentries from gravity-assist trajectories. Aerospace Nuclear Safety Program

    SciTech Connect

    Sharbaugh, R.C.

    1992-03-23

    Motion studies of the General Purpose Heat Source Module, GPHS, which were conducted in the heat pulse intervals associated with entries from earth gravity assist trajectories. The APL six-degree-of-freedom reentry program designated TMAGRA6C was used. The objectives of the studies were to (1) determine whether the GPHS module entering the earth`s atmosphere from an earth-gravity-assist trajectory has a preferred orientation during the heat pulse of reentry, (2) determine the effect of magnus force on the roll rate and angle of attack of the GPHS during an EGA entry, (3) determine the effect of the magnitude of pitch and roll damping on the GPHS motion.

  15. High efficiency in mode-selective frequency conversion.

    PubMed

    Quesada, Nicolás; Sipe, J E

    2016-01-15

    Frequency conversion (FC) is an enabling process in many quantum information protocols. Recently, it has been observed that upconversion efficiencies in single-photon, mode-selective FC are limited to around 80%. In this Letter, we argue that these limits can be understood as time-ordering corrections (TOCs) that modify the joint conversion amplitude of the process. Furthermore, using a simple scaling argument, we show that recently proposed cascaded FC protocols that overcome the aforementioned limitations act as "attenuators" of the TOCs. This observation allows us to argue that very similar cascaded architectures can be used to attenuate TOCs in photon generation via spontaneous parametric downconversion. Finally, by using the Magnus expansion, we argue that the TOCs, which are usually considered detrimental for FC efficiency, can also be used to increase the efficiency of conversion in partially mode-selective FC.

  16. On the transgressiveness of ambiguity: Richard Bruce Nugent and the flow of sexuality and race.

    PubMed

    Bauer, J Edgar

    2015-01-01

    The study focuses on the slender corpus of literary work by Harlem Renaissance poet, author and visual artist Richard Bruce Nugent (1906-1987), arguably America's foremost Black aesthete. As an individualist in the footsteps of post-Hegelian and pre-Nietzschean philosopher Max Stirner (1806-1856), Nugent sought to re-think sexuality and race beyond fixed schemes of categorial distribution. To this end, Nugent deployed a strategy of sexual and racial ambiguity that aimed at situating the uniquely sexed and raced individual within the continuities of ever-diversifying Nature. Nugent's deconstructive approach of sexuality and race proves to be convergent with (but not genealogically dependent on) the universalization of sexual intermediariness and racial miscegenation postulated by German-Jewish sexologist Magnus Hirschfeld during the first third of the twentieth century. Nugent's non-identitarian conception of sex acts anticipated by more than a decade comparable insights propounded by Alfred Kinsey.

  17. Semiclassical dynamics of electron wave packet states with phase vortices.

    PubMed

    Bliokh, Konstantin Yu; Bliokh, Yury P; Savel'ev, Sergey; Nori, Franco

    2007-11-09

    We consider semiclassical higher-order wave packet solutions of the Schrödinger equation with phase vortices. The vortex line is aligned with the propagation direction, and the wave packet carries a well-defined orbital angular momentum (OAM) variant Planck's over 2pil (l is the vortex strength) along its main linear momentum. The probability current coils around the momentum in such OAM states of electrons. In an electric field, these states evolve like massless particles with spin l. The magnetic-monopole Berry curvature appears in momentum space, which results in a spin-orbit-type interaction and a Berry/Magnus transverse force acting on the wave packet. This brings about the OAM Hall effect. In a magnetic field, there is a Zeeman interaction, which, can lead to more complicated dynamics.

  18. A Common Miscitation of William Gilbert

    NASA Astrophysics Data System (ADS)

    Sluijs, Marinus Anthony

    2014-04-01

    Dozens of scientific textbooks [e.g., Spaldin, 2011, p. v; Krijgsman and Langereis, 2009, p. 252; Prölls, 2004, p. 211; Merrill et al., 1996, p. 7; Livingston, 1996, p. 27; Blakely, 1996, pp. xiv, 154; Gillmor, 1990, p. 9] attribute the famous dictum magnus magnes ipse est globus terrestris ("the terrestrial globe is itself a big magnet") to the English physician and scientist William Gilbert (1544-1603). It is repeatedly claimed that these words were contained in the title of Gilbert's book or one of his chapters [e.g., Carlowicz and Lopez, 2002, n.p.; Courtillot, 2002, pp. 26, 49; Lang and Whitney, 1991, p. 120]. Certainly, they convey the thrust of Gilbert's De Magnete, in which it was argued for the first time that the Earth sustains its own magnetic dipole field, on the basis of experimentation on magnets.

  19. Anti-scratching behavioral effects of N-stearoyl-phytosphingosine and 4-hydroxysphinganine in mice.

    PubMed

    Ryu, Kwon-Ryeol; Lee, Bomi; Lee, In-Ah; Oh, Sekwan; Kim, Dong-Hyun

    2010-07-01

    N-Stearoyl-phytosphingosine (SPS) and 4-hydroxysphinganine (phytosphingosine, PS), which are sphingolipids frequently found in mammalian skin, plants, and yeast, have been used as ingredients in cosmetics. In mice, treatment with SPS and PS inhibited histamine-induced scratching behavior and vascular permeability. These agents inhibited the expression of the allergic cytokines, IL-4 and TNF-alpha, and the activation of the transcription factors, NF-kappaB and c-jun, in histamine-stimulated skin tissues. These agents also showed potent anti-histamine effects in the Magnus test using guinea pig ileum. Based on these results, SPS and PS may improve scratching behavioral reactions in skin by regulating the action of histamine and the activation of the transcription factors NF-kappaB and c-jun.

  20. Experiments with a wing from which the boundary layer is removed by pressure or suction

    NASA Technical Reports Server (NTRS)

    Wieland, K

    1928-01-01

    With an unsymmetrical wing and a rotating Magnus cylinder, the lift is produced by the superposition of parallel and circulatory flows. An explanation of the circulatory flow is furnished by the boundary-layer theory of Prandtl and the consequent vortex formation. According to this explanation, it must evidently be possible to increase the circulation either by increasing the size of the stronger (lower) vortex or by decreasing the size of the weaker (upper) vortex. In this sense, according to Professor H. Zickendraht, we have a new type of wing from which the boundary layer is removed by forcing air out or sucking it in through openings in the upper surface of the wing near its trailing edge.

  1. STS-112 crew practices emergency egress training during TCDT

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. - During emergency egress practice on the 195-foot level of the Fixed Service Structure, Launch Pad 39B, STS-112 Mission Specialist Sandra Magnus opens her helmet visor. She and the rest of the crew are taking part in Terminal Countdown Demonstration Test activities, which include a simulated launch countdown. Mission STS-112 aboard Space Shuttle Atlantis is scheduled to launch no earlier than Oct. 2, between 2 and 6 p.m. EDT. STS-112 is the 15th assembly mission to the International Space Station. Atlantis will be carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts.

  2. STS-112 crew boarding Atlantis for TCDT

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- In the White Room at Launch Pad 39B, STS-112 Mission Specialist Sandra Magnus, Ph.D., receives assistance with her spacesuit during a simulated launch countdown, part of Terminal Countdown Demonstration Test activities, a dress rehearsal for launch. Launch of STS-112 aboard Space Shuttle Atlantis is scheduled for Oct. 2, between 2 and 6 p.m. EDT. STS-112 is the 15th assembly mission to the International Space Station. Atlantis will be carrying the S1 Integrated Truss Structure, the first starboard truss segment, which will be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts.

  3. STS-112 Crew walkout of O&C building for TCDT

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- The STS-112 crew strides out of the Checkout and Operations Building on their way to the launch pad and a simulated countdown. On the left, front to back, are Pilot Pamela Melroy and Mission Specialists David Wolf and Fyodor Yurchikhin (RSA). On the right, front to back, are Commander Jeffrey Ashby and Mission Specialists Sandra Magnus and Piers Sellers. Mission STS-112 aboard Space Shuttle Atlantis is scheduled to launch no earlier than Oct. 2, between 2 and 6 p.m. EDT. STS-112 is the 15th assembly mission to the International Space Station. Atlantis will be carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts.

  4. STS-112 crew practices emergency egress training during TCDT

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. - STS-112 Mission Specialist Sandra Magnus (left) sits in the slidewire basket basket on the 195-foot level of the Fixed Service Structure, Launch Pad 39B, while Mission Specialist Piers Sellers (right) reaches for the release lever. They and the rest of the crew are practicing emergency egress from the pad during Terminal Countdown Demonstration Test activities. Mission STS-112 aboard Space Shuttle Atlantis is scheduled to launch no earlier than Oct. 2, between 2 and 6 p.m. EDT. STS-112 is the 15th assembly mission to the International Space Station. Atlantis will be carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts.

  5. STS-112 crew take break during TCDT

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- STS-112 Commander Jeffrey Ashby, Mission Specialist Sandra Magnus, and Pilot Pamela Melroy take a momentary break from training at Pad 39B during Terminal Countdown Demonstration Test activities, which include a simulated launch countdown. Launch of STS-112 aboard Space Shuttle Atlantis is scheduled for Oct. 2, between 2 and 6 p.m. EDT. STS-112 is the 15th assembly mission to the International Space Station. Atlantis will be carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts.

  6. STS-112 crew arrives at KSC's SLF for launch

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- STS-112 Mission Specialist Sandra Magnus is happy to return to KSC to prepare for launch. She will be making her first Shuttle flight. STS-112, aboard Space Shuttle Atlantis, is the 15th assembly mission to the International Space Station. Atlantis will be carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts. The 11-day mission includes three spacewalks. Launch is scheduled for Oct. 2 between 2 and 6 p.m.

  7. STS-112 crew practices emergency egress training during TCDT

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- STS-112 Mission Specialist Sandra Magnus takes a break during emergency egress practice on the 195-foot level of the Fixed Service Structure, Launch Pad 39B. She and the rest of the crew are taking part in Terminal Countdown Demonstration Test activities, which include a simulated launch countdown. Mission STS-112 aboard Space Shuttle Atlantis is scheduled to launch no earlier than Oct. 2, between 2 and 6 p.m. EDT. STS-112 is the 15th assembly mission to the International Space Station. Atlantis will be carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts.

  8. STS-112 crew arrives at KSC's SLF for launch

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- After their arrival at the KSC Shuttle Landing Facility, the STS-112 crew members stride happily to the side of the parking apron and a photo opportunity. From left are Commander Jeffrey Ashby, Mission Specialist Piers Sellers, Pilot Pamela Melroy and Mission Specialists David Wolf, Sandra Magnus and Fyodor Yurchikhin, who is with the Russian Space Agency. Launch is scheduled for Oct. 2 between 2 and 6 p.m. STS-112, aboard Space Shuttle Atlantis, is the 15th assembly mission to the International Space Station. Atlantis will be carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts. The 11-day mission includes three spacewalks.

  9. STS-112 Crew walkout of O&C building for TCDT

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- The STS-112 crew heads for the Astrovan and a ride to the launch pad for a simulated countdown. From left are Mission Specialists Fyodor Yurchikhin (RSA), David Wolf and Piers Sellers; Pilot Pamela Melroy; Mission Specialist Sandra Magnus; and Commander Jeffrey Ashby. Mission STS-112 aboard Space Shuttle Atlantis is scheduled to launch no earlier than Oct. 2, between 2 and 6 p.m. EDT. STS-112 is the 15th assembly mission to the International Space Station. Atlantis will be carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts.

  10. STS-112 Atlantis landing at KSC's shuttle landing facility

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. - Space Shuttle Atlantis is close to touchdown at the Shuttle Landing Facility, completing the 4.5-million-mile journey to the International Space Station. Main gear touchdown occurred at 11:43:40 a.m. EDT; nose gear touchdown at 11:43:48 a.m.; and wheel stop at 11:44:35 a.m. Mission elapsed time was 10:19:58:44. Mission STS-112 expanded the size of the Station with the addition of the S1 truss segment. The returning crew of Atlantis are Commander Jeffrey Ashby, Pilot Pamela Melroy, and Mission Specialists David Wolf, Piers Sellers, Sandra Magnus and Fyodor Yurchikhin. This landing is the 60th at KSC in the history of the Shuttle program.

  11. New species and records of Burmagomphus Williamson, 1907 (Odonata, Gomphidae) from China.

    PubMed

    Zhang, Hao-Miao; Kosterin, Oleg E; Cai, Qing-Hua

    2015-08-07

    Four new species of Burmagomphus Williamson, 1907 are described from Southwestern China: B. apricus sp. nov. from Xishuangbanna National Nature Reserve, Menglun Town, Xishuangbanna Dai Autonomous Prefecture, Yunnan Province; B. magnus sp. nov. from Huayudong, Nanxi Town, Hekou County, Hani-Yi Autonomous Prefecture of Honghe, Yunnan Province, B. dentatus sp. nov. from Zhangjiang River in Xiaoqikong scenic spot, altitude 400 m, Libo County, Guizhou Province, and B. latescens sp. nov. from Sifangjing, Mengding Town, Gengma County, Lincang City, Yunnan Province. New records of Burmagomphus spp. in China are provided, with B. asahinai and B. williamsoni williamsoni for the first time reported from China. A revised checklist of Burmagomhus spp. of China is provided which includes 14 species. A doubtful record of B. arboreus and relations of the newly described species are discussed. All types are deposited in the Collection of Aquatic Animals, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan City, Hubei Province, China.

  12. Production of Recombinant Polypeptides Containing One GA-Module and Analysis of Their Ability to Bind to Human Albumin.

    PubMed

    Bormotova, E A; Gupalova, T V

    2016-11-01

    Surface proteins of many bacterial species interact with human serum albumin (HSA) via a special region of amino acid sequence termed GA module. For instance, surface peptostreptococcal albumin-binding protein of anaerobic bacteria Peptostreptococcus magnus contains one HSA-binding GA-module. Protein G from group G and C Streptococcus strains isolated from humans has HSA-binding region consisting of three GA-modules. HSA-binding protein containing two GA-modules was found in strains of group G Streptococcus of animal origin. We obtained two recombinant polypeptides GA1 and GA2 congaing one GA-module each. Recombinant polypeptide with two GA-modules binds HSA with a much higher affinity than polypeptides GA1 and GA2 containing one GA-module. Polypeptide with the second GAmodule more effectively binds HSA than polypeptides with the GA-module.

  13. STS-112 crew during meal before launch

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- The STS-112 crew relaxes at the traditional crew meal before getting ready for launch later in the day. Seated, from left, are Mission Specialist Piers Sellers and Fyodor Yurchikhin, Pilot Pamela Melroy, Commander Jeffrey Ashby, and Mission Specialists Sandra Magnus and David Wolf. STS-112 is the 15th assembly flight to the International Space Station, carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts. On the 11-day mission, three spacewalks are planned to attach the S1 truss to the Station. Launch is scheduled for 3:46 p.m. EDT from Launch Pad 39B.

  14. Guided current-induced skyrmion motion in 1D potential well

    PubMed Central

    Purnama, I.; Gan, W. L.; Wong, D. W.; Lew, W. S.

    2015-01-01

    Magnetic skyrmions are particle-like magnetization configurations which can be found in materials with broken inversion symmetry. Their topological nature allows them to circumvent around random pinning sites or impurities as they move within the magnetic layer, which makes them interesting as information carriers in memory devices. However, when the skyrmion is driven by a current, a Magnus force is generated which leads to the skyrmion moving away from the direction of the conduction electron flow. The deflection poses a serious problem to the realization of skyrmion-based devices, as it leads to skyrmion annihilation at the film edges. Here, we show that it is possible to guide the movement of the skyrmion and prevent it from annihilating by surrounding and compressing the skyrmion with strong local potential barriers. The compressed skyrmion receives higher contribution from the spin transfer torque, which results in the significant increase of the skyrmion speed. PMID:26024469

  15. Shapiro spikes and negative mobility for skyrmion motion on quasi-one-dimensional periodic substrates

    NASA Astrophysics Data System (ADS)

    Reichhardt, C.; Reichhardt, C. J. Olson

    2017-01-01

    Using a simple numerical model of skyrmions in a two-dimensional system interacting with a quasi-one-dimensional periodic substrate under combined dc and ac drives where the dc drive is applied perpendicular to the substrate periodicity, we show that a rich variety of novel phase-locking dynamics can occur due to the influence of the Magnus term on the skyrmion dynamics. Instead of Shapiro steps, the velocity response in the direction of the dc drive exhibits a series of spikes, including extended dc drive intervals over which the skyrmions move in the direction opposite to the dc drive, producing negative mobility. There are also specific dc drive values at which the skyrmions move exactly perpendicular to the dc drive direction, giving a condition of absolute transverse mobility.

  16. Does Kutta lift exist on a vortex ring in a uniform cross flow?

    NASA Astrophysics Data System (ADS)

    Lim, T. T.; Lua, K. B.; Thet, K.

    2008-05-01

    Past works [Y. K. Chang and A. D. Vakili, Phys. Fluids 7, 1583 (1995); R. Sau and K. Mahesh, AIAA Paper No. 2007-1316] show that a vortex ring ejected normal to a cross flow tilts and deforms as it propagates downstream, and they attribute this phenomenon to the Kutta lift or Magnus effect. Here, we show through a controlled experiment that there is no physical evidence of the existence of a Kutta lift when a fully developed vortex ring is exposed to a uniform cross flow. The observed phenomenon could be attributed to the modification of vorticity distribution of the vortex core due to the combined effect of the cross flow itself and the entrainment of boundary layer material during the formation of vortex ring.

  17. STS-112 Atlantis landing at KSC's shuttle landing facility

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. - Space Shuttle Atlantis drops to the runway at the Shuttle Landing Facility, completing the 4.5-million-mile journey to the International Space Station. Main gear touchdown occurred at 11:43:40 a.m. EDT; nose gear touchdown at 11:43:48 a.m.; and wheel stop at 11:44:35 a.m. Mission elapsed time was 10:19:58:44. Mission STS-112 expanded the size of the Station with the addition of the S1 truss segment. The returning crew of Atlantis are Commander Jeffrey Ashby, Pilot Pamela Melroy, and Mission Specialists David Wolf, Piers Sellers, Sandra Magnus and Fyodor Yurchikhin. This landing is the 60th at KSC in the history of the Shuttle program.

  18. Somatostatin-immunoreactive nerve cell bodies and fibers in the medulla oblongata et spinalis.

    PubMed

    Forssmann, W G; Burnweit, C; Shehab, T; Triepel, J

    1979-10-01

    Complete serial sectioning of the medulla oblongata in monkey, cat, guinea pig, and japanese dancing mouse and incubation for somatostatin-immunoreaction was carried out. Numerous regions of the medulla oblongata such as the nucleus reticularis gigantocellularis, nucleus cuneatus et gracillis, nucleus raphe magnus, nucleus tractus solitarius, nucleus vestibularis, and parts of the oliva contain dense networks of somatostatin-immunoreactive nerve fibers. Cell bodies were seen in the nucleus reticularis medullae oblongatae. In the spinal cord the sections from each segment were analyzed, showing the highest concentrations of somatostatinergic fibers in the substantia gelantinosa of the columna dorsalis. Cell bodies were seen in the zona intermedia centralis, especially in the upper cervical segments. Many positive fibers were also seen in the entire zona intermedia and the columna ventralis. Especially prominent was the immunoreactivity in the zona intermediolateralis of the thoracic segments and the columna ventralis of the lower lumbar and sacral segments.

  19. Skyrmion dynamics in a chiral magnet driven by periodically varying spin currents*

    NASA Astrophysics Data System (ADS)

    Zhu, Rui; Zhang, Yin-Yan

    2016-12-01

    In this work, we investigated the spin dynamics in a slab of chiral magnets induced by an alternating (ac) spin current. Periodic trajectories of the skyrmion in real space are discovered under the ac current as a result of the Magnus and viscous forces, which originate from the Gilbert damping, the spin transfer torque, and the β-nonadiabatic torque effects. The results are obtained by numerically solving the Landau-Lifshitz-Gilbert equation and can be explained by the Thiele equation characterizing the skyrmion core motion. Supplementary material in the form of one avi file available from the Journal web page at: http://dx.doi.org/10.1140/epjb/e2016-70467-9

  20. STS-112 crew talks to media after landing

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. - The STS-112 crew pauses at the microphone in front of Atlantis after exiting the crew transport vehicle. From left are Mission Specialist Sandra Magnus, Pilot Pamela Melroy, Commander Jeffrey Ashby, and Mission Specialists David Wolf, Fyodor Yurchikhin and Piers Sellers. The flawless landing of Space Shuttle Atlantis on Runway 33 at KSC completed a 4.5-million-mile journey to the International Space Station. Main gear touchdown occurred at 11:43:40 a.m. EDT; nose gear touchdown at 11:43:48 a.m.; and wheel stop at 11:44:35 a.m. Mission elapsed time was 10:19:58:44. Mission STS-112 expanded the size of the Station with the addition of the S1 truss segment.

  1. STS-112 crew talks to media after landing

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- The STS-112 crew clown for the camera in front of Atlantis after saying a few words about their 4.5-million-mile journey to the International Space Station. From left are Mission Specialist Sandra Magnus, Pilot Pamela Melroy, Commander Jeffrey Ashby, and Mission Specialists David Wolf, Fyodor Yurchikhin and Piers Sellers. The flawless landing of Space Shuttle Atlantis on Runway 33 at KSC completed the 10 day, 19 hour, 58 minute, 44 second- long mission. Main gear touchdown occurred at 11:43:40 a.m. EDT; nose gear touchdown at 11:43:48 a.m.; and wheel stop at 11:44:35 a.m. Mission STS-112 expanded the size of the Station with the addition of the S1 truss segment.

  2. [CCA of water beetles' distribution and environmental factors in lentic samples of north Changbai Mountain].

    PubMed

    We, Yulian; Ji, Lanzhu; Wang, Miao; Zhao, Min

    2002-01-01

    The relationship between 28 species water beetles in 12 lentic samples and environmental factors of North Chang-bai Mountain was studied by Cononical Correspondence Analysis (CCA). The results showed that degree of underwater humus and altitude are the major factors correlated with beetles distribution, and the correlation coefficients of environmental factors and axes of CCA were 0.8371 and 0.7206 respectively, while water temperature and plant density also had certain effects. Under the influence of environmental factors, the water beetles' populations were different in different habitat. Coelambus impressopunctatus, Colymbetes magnus, Helophorus browni, Haliplus spp. distributed in deep water pool. Water temperature was not important for those beetles. Ilybius sp. and Limnebius glabriventris correlated with altitude and humus.

  3. What Is the Best Launch Angle To Hit a Home Run?

    NASA Astrophysics Data System (ADS)

    Kagan, David

    2010-04-01

    Your students will proudly raise their hands and answer, "45 degrees!" They are, however, answering a different question. It is true that in the absence of air resistance, for a given initial speed, the launch angle that maximizes the range is 45°. For a real homer, there are many complicating factors that make the question far more challenging to answer. Here is a partial list: 1. The initial speed off the bat is not fixed. Garvey's law, "The harder you hit it, the further it goes" is definitely at play; 2. Air resistance is a substantial influence on the flight of the ball. ; 3. The backspin on a well-hit ball creates lift due to the Magnus effect.2; 4. Atmospheric conditions such as humidity, temperature, air density, and the wind affect the motion as well.3; 5. Baseball parks are unique in size and shape. So, a home run in one park may not be a home run in another.

  4. Centronuclear myopathy related to dynamin 2 mutations: Clinical, morphological, muscle imaging and genetic features of an Italian cohort

    PubMed Central

    Catteruccia, Michela; Fattori, Fabiana; Codemo, Valentina; Ruggiero, Lucia; Maggi, Lorenzo; Tasca, Giorgio; Fiorillo, Chiara; Pane, Marika; Berardinelli, Angela; Verardo, Margherita; Bragato, Cinzia; Mora, Marina; Morandi, Lucia; Bruno, Claudio; Santoro, Lucio; Pegoraro, Elena; Mercuri, Eugenio; Bertini, Enrico; D’Amico, Adele

    2013-01-01

    Mutations in dynamin 2 (DNM2) gene cause autosomal dominant centronuclear myopathy and occur in around 50% of patients with centronuclear myopathy. We report clinical, morphological, muscle imaging and genetic data of 10 unrelated Italian patients with centronuclear myopathy related to DNM2 mutations. Our results confirm the clinical heterogeneity of this disease, underlining some peculiar clinical features, such as severe pulmonary impairment and jaw contracture that should be considered in the clinical follow-up of these patients. Muscle MRI showed a distinct pattern of involvement, with predominant involvement of soleus and tibialis anterior in the lower leg muscles, followed by hamstring muscles and adductor magnus at thigh level and gluteus maximus. The detection of three novel DNM2 mutations and the first case of somatic mosaicism further expand the genetic spectrum of the disease. PMID:23394783

  5. Electromagnetotoroid Structures in Propulsion and Astrophysics

    NASA Astrophysics Data System (ADS)

    Pinheiro, Mario J.

    2010-01-01

    We introduce the concept of electromagnetotoroid in astrophysics and its role in polar jets, showing that it represents the onset of Abraham's force driven by some external source, such for example, gas fall to star center. We have shown in this paper that the Abraham's force term is the analogue of the Magnus force, and thus represents the formation of vortex structures, of electromagnetic nature, in the fabric of space-time. The proposed concept can be transposed for spaceship propulsion. This study points to prove that major processes for propulsion on Earth (e.g., birds, fishes) and in the Universe (e.g., HH objects) have all the same underlying nature, the formation of vortical structures being at their basis.

  6. Short-range intervortex interaction and interacting dynamics of half-quantized vortices in two-component Bose-Einstein condensates

    NASA Astrophysics Data System (ADS)

    Kasamatsu, Kenichi; Eto, Minoru; Nitta, Muneto

    2016-01-01

    We study the interaction and dynamics of two half-quantized vortices in two-component Bose-Einstein condensates. Using the Padé approximation for the vortex core profile, we calculate the intervortex potential, whose asymptotic form for a large distance has been derived by Eto et al. [Phys. Rev. A 83, 063603 (2011), 10.1103/PhysRevA.83.063603]. Through numerical simulations of the two-dimensional Gross-Pitaevskii equations, we reveal different kinds of dynamical trajectories of the vortices depending on the combinations of signs of circulations and the intercomponent density coupling. Under the adiabatic limit, we derive the equations of motion for the vortex coordinates, in which the motion is caused by the balance between Magnus force and the intervortex forces. The initial velocity of the vortex motion can be explained quantitatively by this point vortex approximation, but understanding the long-time behavior of the dynamics needs more consideration beyond our model.

  7. Direct and indirect pathways to lamina I in the medulla oblongata and spinal cord of the cat

    NASA Technical Reports Server (NTRS)

    Holstege, Gert

    1988-01-01

    The pathways to lamina I in the medulla oblongata and spinal cord of the cat were traced using horse-radish-peroxidase (HRP) and autoradiographic techniques. The HRP results indicated that several neuronal cell groups in the brain stem and hypothalamus project to the spinal cord throughout its total length. The autoradiographic tracing results demonstrated that the strongest projections to lamina I are derived from the following four areas: the caudal nucleus raphe magnus (NRM), the ventral part of the caudal pontine and NRM, the contralaterally projecting lateral pontine or paralemniscal tegmentum, and the paraventricular nucleus of the hypothalamus. In addition, a limited, especially at lumbosacral levels, distinct projection to lamina I was found to originate in the most caudal part of the medullary tegmentum.

  8. High efficiency in Mode Selective Frequency Conversion for Optical Quantum Information Processing

    NASA Astrophysics Data System (ADS)

    Quesada, Nicolas; Sipe, J. E.

    Mode selective Frequency conversion (FC) is an enabling process in many quantum information protocols. Recently, it has been observed that upconversion efficiencies in single-photon, mode-selective FC are limited to around 80%. In this contribution we show that these limits can be understood as time ordering corrections (TOCs) that modify the joint conversion amplitude of the process. Furthermore we show, using a simple scaling argument, that recently proposed cascaded FC protocols that overcome the aforementioned limitations act as ``attenuators'' of the TOCs. This observation allows us to argue that very similar cascaded architectures can be used to attenuate TOCs in photon generation via spontaneous parametric down-conversion. Finally, by using the Magnus expansion, we argue that the TOCs, which are usually considered detrimental for FC efficiency, can also be used to increase the efficiency of conversion in partially mode selective FC.

  9. Antiferromagnetic skyrmions

    NASA Astrophysics Data System (ADS)

    Tretiakov, Oleg; Barker, Joseph

    Skyrmions are topologically protected entities in magnetic materials which have the potential to be used in spintronics for information storage and processing. However, skyrmions in ferromagnets have some intrinsic difficulties which must be overcome to use them for spintronic applications, such as the inability to move straight along current. We show that skyrmions can also be stabilized and manipulated in antiferromagnetic materials. An antiferromagnetic skyrmion is a compound topological object with a similar but of opposite sign spin texture on each sublattice, which e.g. results in a complete cancelation of the Magnus force. We find that the composite nature of antiferromagnetic skyrmions gives rise to different dynamical behavior, both due to an applied current and temperature effects. O.A.T. and J.B. acknowledge support by the Grants-in-Aid for Scientific Research (Nos. 25800184, 25247056, 25220910 and 15H01009) from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan and SpinNet.

  10. Sound guidelines keep Alwyn field N. Sea project on track

    SciTech Connect

    Picard, D.

    1987-04-27

    Key initial guidelines have helped keep the Alwyn North Sea project on track as it heads toward production start-up by the end of 1987. Before detailing the project, elaborating on how these guidelines have shaped it and have been reflected in the work since project conception, some comments on the complex field in British waters and the participants are in order. The Alwyn field is located in the U.K. Blocks 3/9 and 3/4, in the northern North Sea. This is an area which is already quite dense with existing platforms such as Magnus, North Cormorant, Brent, and others. The field is approximately 100 miles northeast of the Shetland Islands, in a water depth of 130 m (422 ft).

  11. STS-112 Atlantis landing at KSC's shuttle landing facility

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. - A fire rescue truck stands by for safety reasons as Space Shuttle Atlantis slows to a stop on Runway 33 at the Shuttle Landing Facility, completing the 4.5-million-mile journey to the International Space Station. Main gear touchdown occurred at 11:43:40 a.m. EDT; nose gear touchdown at 11:43:48 a.m.; and wheel stop at 11:44:35 a.m. Mission elapsed time was 10:19:58:44. Mission STS-112 expanded the size of the Station with the addition of the S1 truss segment. The returning crew of Atlantis are Commander Jeffrey Ashby, Pilot Pamela Melroy, and Mission Specialists David Wolf, Piers Sellers, Sandra Magnus and Fyodor Yurchikhin. This landing is the 60th at KSC in the history of the Shuttle program. .

  12. [SCIENCE AND DREAMS IN THE MIDDLE AGES: IL "DE SOMNIIS" DI BOEZIO DI DACIA].

    PubMed

    Feti, Viola

    2015-01-01

    Boethius of Dacia's opera "De somnis" can be defined as a brief treaty that partially follows the traditional quaestio scheme. It includes a passage that seems to copy Etienne Tempier's proposition number sixty-five, which condemns the importance attributed to astrology by many medieval authors. Boethius moves off Aristotle's "De somno et vigilia" idea of physiological dreams to assert a new kind of oneiric phenomena linked to constellations, that, according to the author, aren't divinely inspired, whereas they are to be considered as natural events. Boethius isn't the only philosopher who writes about this particular type of dream as another medieval author, Albertus Magnus, in his "Speculum Astronomiae", describes astrology and its relationship to medicine.

  13. STS-112 Atlantis landing at KSC's shuttle landing facility

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- Space Shuttle Atlantis stirs up dust as it touches down on Runway 33 at the Shuttle Landing Facility, completing the 4.5-million-mile journey to the International Space Station. Main gear touchdown occurred at 11:43:40 a.m. EDT; nose gear touchdown at 11:43:48 a.m.; and wheel stop at 11:44:35 a.m. Mission elapsed time was 10:19:58:44. Mission STS-112 expanded the size of the Station with the addition of the S1 truss segment. The returning crew of Atlantis are Commander Jeffrey Ashby, Pilot Pamela Melroy, and Mission Specialists David Wolf, Piers Sellers, Sandra Magnus and Fyodor Yurchikhin. This landing is the 60th at KSC in the history of the Shuttle program. .

  14. Higher-order wide-angle split-step spectral method for non-paraxial beam propagation.

    PubMed

    Hokr, Brett H; Clark, C D; Grotheer, Rachel E; Thomas, Robert J

    2013-07-01

    We develop a higher-order method for non-paraxial beam propagation based on the wide-angle split-step spectral (WASSS) method previously reported [Clark and Thomas, Opt. Quantum. Electron., 41, 849 (2010)]. The higher-order WASSS (HOWASSS) method approximates the Helmholtz equation by keeping terms up to third-order in the propagation step size, in the Magnus expansion. A symmetric exponential operator splitting technique is used to simplify the resulting exponential operators. The HOWASSS method is applied to the problem of waveguide propagation, where an analytical solution is known, to demonstrate the performance and accuracy of the method. The performance enhancement gained by implementing the HOWASSS method on a graphics processing unit (GPU) is demonstrated. When highly accurate results are required the HOWASSS method is shown to be substantially faster than the WASSS method.

  15. Theory of K/sup n/L/sup v/ multiple vacancy production by heavy ions

    SciTech Connect

    Becker, R.L.; Ford, A.L.; Reading, J.F.

    1984-01-01

    Observation of intensities of K/sub ..cap alpha../ x-ray or Auger satellites and hyper-satellites together with fluorescence yields provides knowledge of KL/sup v/ and K/sup 2/l/sup v/ vacancy distributions produced by ion-atom collisions. The traditional theory used since approx. 1972 employs a single-particle model and a weak-coupling ionization approximation. We review our recent extensions of the theory to include Paul correlations in the independent Fermi particle model, a unitary collision theory in the first Magnus and coupled-channels approximations, electron transfer to the projectile, and contributions from shakeoff which interfere with the collision-induced amplitudes.

  16. Comparing the dynamics of skyrmions and superconducting vortices

    NASA Astrophysics Data System (ADS)

    Olson Reichhardt, C. J.; Lin, S. Z.; Ray, D.; Reichhardt, C.

    2014-08-01

    Vortices in type-II superconductors have attracted enormous attention as ideal systems in which to study nonequilibrium collective phenomena, since the self-ordering of the vortices competes with quenched disorder and thermal effects. Dynamic effects found in vortex systems include depinning, nonequilibrium phase transitions, creep, structural order-disorder transitions, and melting. Understanding vortex dynamics is also important for applications of superconductors which require the vortices either to remain pinned or to move in a controlled fashion. Recently, topological defects called skyrmions have been realized experimentally in chiral magnets. Here we highlight similarities and differences between skyrmion dynamics and vortex dynamics. Many of the previous ideas and experimental setups that have been applied to superconducting vortices can also be used to study skyrmions. We also discuss some of the differences between the two systems, such as the potentially large contribution of the Magnus force in the skyrmion system that can dramatically alter the dynamics and transport properties.

  17. Semiclassical Dynamics of Electron Wave Packet States with Phase Vortices

    SciTech Connect

    Bliokh, Konstantin Yu.; Bliokh, Yury P.; Savel'ev, Sergey; Nori, Franco

    2007-11-09

    We consider semiclassical higher-order wave packet solutions of the Schroedinger equation with phase vortices. The vortex line is aligned with the propagation direction, and the wave packet carries a well-defined orbital angular momentum (OAM) ({Dirac_h}/2{pi})l (l is the vortex strength) along its main linear momentum. The probability current coils around the momentum in such OAM states of electrons. In an electric field, these states evolve like massless particles with spin l. The magnetic-monopole Berry curvature appears in momentum space, which results in a spin-orbit-type interaction and a Berry/Magnus transverse force acting on the wave packet. This brings about the OAM Hall effect. In a magnetic field, there is a Zeeman interaction, which, can lead to more complicated dynamics.

  18. Transformation of the vector part of the 4-momentum in the Dirac equation and in Maxwell's equations in Majorana form for chiral media

    NASA Astrophysics Data System (ADS)

    Sadykov, N. R.

    2011-03-01

    It is suggested to extend the results obtained for Maxwell's equations in Majorana form (spin-1 particles) for spin particles with a half-integer spin and a nonzero mass. It is shown that in an unbounded "chiral medium" (twisted media) the degeneration existing between particles of different helicities is removed. For ultrarelativistic particles, an analog to the inverse optical Magnus effect follows where the effect is determined by the chirality of the medium. From the inverse scattering problem for the transforms under consideration it follows that the amplitude of the wave function of a particle in a chiral medium can vary with time according to a linear law (for example, the process of neutrino (antineutrino) production or annihilation), and the parameters of the medium satisfy the evolution equation.

  19. Geometrical Optics of Beams with Vortices: Berry Phase and Orbital Angular Momentum Hall Effect

    SciTech Connect

    Bliokh, Konstantin Yu.

    2006-07-28

    We consider propagation of a paraxial beam carrying the spin angular momentum (polarization) and intrinsic orbital angular momentum (IOAM) in a smoothly inhomogeneous isotropic medium. It is shown that the presence of IOAM can dramatically enhance and rearrange the topological phenomena that previously were considered solely in connection to the polarization of transverse waves. In particular, the appearance of a new type of Berry phase that describes the parallel transport of the beam structure along a curved ray is predicted. We derive the ray equations demonstrating the splitting of beams with different values of IOAM. This is the orbital angular momentum Hall effect, which resembles the Magnus effect for optical vortices. Unlike the spin Hall effect of photons, it can be much larger in magnitude and is inherent to waves of any nature. Experimental means to detect the phenomena are discussed.

  20. Rarefaction Effects in Hypersonic Aerodynamics

    NASA Astrophysics Data System (ADS)

    Riabov, Vladimir V.

    2011-05-01

    The Direct Simulation Monte-Carlo (DSMC) technique is used for numerical analysis of rarefied-gas hypersonic flows near a blunt plate, wedge, two side-by-side plates, disk, torus, and rotating cylinder. The role of various similarity parameters (Knudsen and Mach numbers, geometrical and temperature factors, specific heat ratios, and others) in aerodynamics of the probes is studied. Important kinetic effects that are specific for the transition flow regime have been found: non-monotonic lift and drag of plates, strong repulsive force between side-by-side plates and cylinders, dependence of drag on torus radii ratio, and the reverse Magnus effect on the lift of a rotating cylinder. The numerical results are in a good agreement with experimental data, which were obtained in a vacuum chamber at low and moderate Knudsen numbers from 0.01 to 10.

  1. A brief summary of the attempts to develop large wind-electric generating systems in the U.S.

    NASA Technical Reports Server (NTRS)

    Savino, J. M.

    1974-01-01

    Interest in developing large wind-electric generating systems in the United States was stimulated primarily by one man, Palmer C. Putnam. He was responsible for the construction of the largest wind-power system ever built - the 1250 kilowatt Smith-Putnam wind-electric plant. The existence of this system prompted the U.S. Federal Power Commission to investigate the potential of using the winds as a source energy. Also, in 1933 prior to Putnam's effort, there was an abortive attempt by J. D. Madaras to develop a wind system based on the Magnus effect. These three projects comprise the only serious efforts in America to develop large wind driven plants. In this paper, the history of each project is briefly described. Also discussed are some of the reasons why wind energy was not seriously considered as a major source of energy for the U.S.

  2. Static and Dynamical Properties of Antiferromagnetic Skyrmions in the Presence of Applied Current and Temperature

    NASA Astrophysics Data System (ADS)

    Barker, Joseph; Tretiakov, Oleg A.

    2016-04-01

    Skyrmions are topologically protected entities in magnetic materials which have the potential to be used in spintronics for information storage and processing. However, Skyrmions in ferromagnets have some intrinsic difficulties which must be overcome to use them for spintronic applications, such as the inability to move straight along current. We show that Skyrmions can also be stabilized and manipulated in antiferromagnetic materials. An antiferromagnetic Skyrmion is a compound topological object with a similar but of opposite sign spin texture on each sublattice, which, e.g., results in a complete cancellation of the Magnus force. We find that the composite nature of antiferromagnetic Skyrmions gives rise to different dynamical behavior due to both an applied current and temperature effects.

  3. STS-112 crew in front of Launch Pad 39B before launch

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. - STS-112 Commander Jeffrey S. Ashby poses in front of Launch Pad 39B during a tour of Kennedy Space Center prior to launch. Also on the tour were the other members of the crew including Pilot Pamela Ann Melroy and Mission Speci alists David A. Wolf, Sandra H. Magnus, Piers J. Sellers, and Fyodor N. Yurchikhin of the Russian Space Agency. The launch of Space Shuttle Atlantis was postponed today to no earlier than Thursday, Oct. 3, while weather forecasters and the mission managem ent team assess the possible effect Hurricane Lili may have on the Mission Control Center located at the Lyndon B. Johnson Space Center in Houston, Texas.

  4. Non-Abelian evolution of electromagnetic waves in a weakly anisotropic inhomogeneous medium

    SciTech Connect

    Bliokh, K. Yu.; Frolov, D. Yu.; Kravtsov, Yu. A.

    2007-05-15

    A theory of electromagnetic wave propagation in a weakly anisotropic smoothly inhomogeneous medium is developed, based on the quantum-mechanical diagonalization procedure applied to Maxwell equations. The equations of motion for the translational (ray) and intrinsic (polarization) degrees of freedom are derived ab initio. The ray equations take into account the optical Magnus effect (spin Hall effect of photons) as well as trajectory variations owing to the medium anisotropy. Polarization evolution is described by the precession equation for the Stokes vector. In the generic case, the evolution of wave turns out to be non-Abelian: it is accompanied by mutual conversion of the normal modes and periodic oscillations of the ray trajectories analogous to electron zitterbewegung. The general theory is applied to examples of wave evolution in media with circular and linear birefringence.

  5. Multitime correlation functions in nonclassical stochastic processes

    NASA Astrophysics Data System (ADS)

    Krumm, F.; Sperling, J.; Vogel, W.

    2016-06-01

    A general method is introduced for verifying multitime quantum correlations through the characteristic function of the time-dependent P functional that generalizes the Glauber-Sudarshan P function. Quantum correlation criteria are derived which identify quantum effects for an arbitrary number of points in time. The Magnus expansion is used to visualize the impact of the required time ordering, which becomes crucial in situations when the interaction problem is explicitly time dependent. We show that the latter affects the multi-time-characteristic function and, therefore, the temporal evolution of the nonclassicality. As an example, we apply our technique to an optical parametric process with a frequency mismatch. The resulting two-time-characteristic function yields full insight into the two-time quantum correlation properties of such a system.

  6. Edge tunneling of vortices in superconducting thin films

    SciTech Connect

    Iengo, R. |; Jug, G. |

    1996-11-01

    We investigate the phenomenon of the decay of a supercurrent due to the zero-temperature quantum tunneling of vortices from the edge in a thin superconducting film in the absence of an external magnetic field. An explicit formula is derived for the tunneling rate of vortices, which are subject to the Magnus force induced by the supercurrent, through the Coulomb-like potential barrier binding them to the film{close_quote}s edge. Our approach ensues from the nonrelativistic version of a Schwinger-type calculation for the decay of the two-dimensional vacuum previously employed for describing vortex-antivortex pair nucleation in the bulk of the sample. In the dissipation-dominated limit, our explicit edge-tunneling formula yields numerical estimates which are compared with those obtained for bulk nucleation to show that both mechanisms are possible for the decay of a supercurrent. {copyright} {ital 1996 The American Physical Society.}

  7. The Versatile Elastohydrodynamics of a Free Particle near a Thin Soft Wall

    NASA Astrophysics Data System (ADS)

    Salez, Thomas; Saintyves, Baudouin; Mahadevan, L.

    2015-03-01

    We address the free motion of a buoyant particle inside a viscous fluid, in the vicinity of a thin compressible elastic wall. After discussing the main scalings, we obtain analytically the dominant drag forces within the soft lubrication approximation. By including those into the equations of motion of the particle, we establish a general governing system of three coupled nonlinear and singular differential equations, that describe the three essential motions: sedimentation, hydroplaning, and hydrospinning, through four dimensionless control parameters. Numerical integration allows us to predict a wide zoology of exotic solutions - despite the low-Reynolds feature of the flow - including: spontaneous oscillation, Magnus-like effect, enhanced sedimentation, and boomerang-like effect. We compare these predictions to experiments. The presented elementary approach could be of interest in the description of a broad variety of elastohydrodynamical phenomena, including: landslides, ageing of cartilaginous joints, and motion of a cell in a microfluidic channel or in a blood vessel.

  8. Self-propulsion of a body with rigid surface and variable coefficient of lift in a perfect fluid

    NASA Astrophysics Data System (ADS)

    Ramodanov, Sergey M.; Tenenev, Valentin A.; Treschev, Dmitry V.

    2012-11-01

    We study the system of a 2D rigid body moving in an unbounded volume of incompressible, vortex-free perfect fluid which is at rest at infinity. The body is equipped with a gyrostat and a so-called Flettner rotor. Due to the latter the body is subject to a lifting force (Magnus effect). The rotational velocities of the gyrostat and the rotor are assumed to be known functions of time (control inputs). The equations of motion are presented in the form of the Kirchhoff equations. The integrals of motion are given in the case of piecewise continuous control. Using these integrals we obtain a (reduced) system of first-order differential equations on the configuration space. Then an optimal control problem for several types of the inputs is solved using genetic algorithms.

  9. A brief summary of the attempts to develop large wind-electric generating systems in the US

    NASA Technical Reports Server (NTRS)

    Savino, J. M.

    1974-01-01

    Interest in developing large wind-electric generating systems in the United States was simulated primarily by one man, Palmer C. Putnam. He was responsible for the construction of the 1250 kilowatt Smith-Putnam wind-electric plant. The existence of this system prompted the U. S. Federal Power Commission to investigate the potential of using the winds as a source energy. Also, in 1933 prior to Putnam's effort, there was an abortive attempt by J. D. Madaras to develop a wind system based on the Magnus effect. These three projects comprise the only serious efforts in America to develop large wind driven plants. In this paper the history of each project is briefly described. Also discussed are some of the reasons why wind energy was not seriously considered as a major source of energy for the U. S.

  10. Quantum vortex dynamics in two-dimensional neutral superfluids

    SciTech Connect

    Wang, C.-C. Joseph; Duine, R. A.; MacDonald, A. H.

    2010-01-15

    We derive an effective action for the vortex-position degree of freedom in a superfluid by integrating out condensate phase- and density-fluctuation environmental modes. When the quantum dynamics of environmental fluctuations is neglected, we confirm the occurrence of the vortex Magnus force and obtain an expression for the vortex mass. We find that this adiabatic approximation is valid only when the superfluid droplet radius R, or the typical distance between vortices, is very much larger than the coherence length xi. We go beyond the adiabatic approximation numerically, accounting for the quantum dynamics of environmental modes and capturing their dissipative coupling to condensate dynamics. For the case of an optical-lattice superfluid, we demonstrate that vortex motion damping can be adjusted by tuning the ratio between the tunneling energy J and the on-site interaction energy U. We comment on the possibility of realizing vortex-Landau-level physics.

  11. Elastohydrodynamics of a free cylinder near a soft wall

    NASA Astrophysics Data System (ADS)

    Mahadevan, L.; Salez, Thomas

    2015-11-01

    We consider the motion of a fluid-immersed negatively buoyant particle in the vicinity of a thin compressible elastic wall. We use scaling arguments to establish different regimes of settling, sliding, rolling and complement these estimates using thin-film lubrication dynamics to determine an asymptotic theory for the sedimentation, sliding, and spinning motions of a cylinder. Numerical integration of the resulting equations confirms our scaling relations and further yields a range of behaviours such as spontaneously oscillations when sliding, lift via a Magnus-like effect, a spin-induced reversal effect, and an unusual sedimentation singularity. Our description also allows us to address a sedimentation-sliding transition that can lead to the particle coasting over very long distances, similar to certain geophysical phenomena.

  12. Vortex loops: Are they always doomed to die

    SciTech Connect

    Ben-Ya'acov, U. )

    1995-03-15

    The effective equations of motion of relativistic strings in material media are derived and applied to moving rings with a time-dependent radius. The equations contain the Magnus force, due to the motion of the ring relative to the medium, whose eventual effect is the possible stabilization of the ring against shrinking. A constant solution is identified, and small fluctuations around it are bound, demonstrating the stability of the solution. If the string loops created in the cosmological cosmic string scenario interact via this mechanism with a formed-up Higgs particle condensate, then the stabilizing velocities are [similar to][delta][sub loop]/[ital R][sub loop], and the overall effect of this phenomenon is to stabilize large loops and reduce the general disappearance rate of the string loops.

  13. Increases in vocalization and motor reflex thresholds are influenced by the site of morphine microinjection: comparisons following administration into the periaqueductal gray, ventral medulla, and spinal subarachnoid space.

    PubMed

    Borszcz, G S

    1995-06-01

    The relative influence of morphine microinjected into the periaqueductal gray, ventral medulla (nucleus raphé magnus or nucleus reticularis gigantocellularis), or spinal subarachnoid space on the thresholds of responses organized at spinal (spinal motor reflexes, SMRs), medullary (vocalizations elicited during shock, VDSs), and rhinencephalic-diencephalic (vocalization after discharges, VADs) levels of the neuraxis was assessed. Dose-dependent increases in response thresholds differed with the site of morphine injection. These results indicate that the mu-opiate-receptor-linked systems in the mesencephalon, medulla, and spinal cord exert differential antinociceptive effects on pain behaviors organized at different levels of the neuraxis. A hypothesis is offered regarding the mechanisms through which morphine inhibits nociceptive transmission through various levels of the CNS. VADs are promoted as a model system for analyzing the affective-motivational dimension of the pain experience.

  14. An Unusual Course and Termination of Small Saphenous Vein: A Case Report

    PubMed Central

    Shetty, Prakashchandra; D’Souza, Melanie Rose

    2016-01-01

    The superficial veins of the lower limb can vary in their course and termination. We report a relatively rare type of variation in the course and termination of small saphenous vein. The small saphenous vein had normal origin and course in the leg. However, instead of terminating into the popliteal vein, it continued up in the posterior compartment of the thigh and terminated into the femoral vein after piercing the fleshy part of the adductor magnus muscle. This course might lead to varicosity of the small saphenous vein due to the compression by the fleshy fibres of adductor magus near its termination. The case may be of interest to general and plastic surgeons and even cardiothoracic surgeons. PMID:27134850

  15. Direction of spin axis and spin rate of the pitched baseball.

    PubMed

    Jinji, Tsutomu; Sakurai, Shinji

    2006-07-01

    In this study, we aimed to determine the direction of the spin axis and the spin rate of pitched baseballs and to estimate the associated aerodynamic forces. In addition, the effects of the spin axis direction and spin rate on the trajectory of a pitched baseball were evaluated. The trajectories of baseballs pitched by both a pitcher and a pitching machine were recorded using four synchronized video cameras (60 Hz) and were analyzed using direct linear transform (DLT) procedures. A polynomial function using the least squares method was used to derive the time-displacement relationship of the ball coordinates during flight for each pitch. The baseball was filmed immediately after ball release using a high-speed video camera (250 Hz), and the direction of the spin axis and the spin rate (omega) were calculated based on the positional changes of the marks on the ball. The lift coefficient was correlated closely with omegasinalpha (r = 0.860), where alpha is the angle between the spin axis and the pitching direction. The term omegasinalpha represents the vertical component of the velocity vector. The lift force, which is a result of the Magnus effect occurring because of the rotation of the ball, acts perpendicularly to the axis of rotation. The Magnus effect was found to be greatest when the angular and translational velocity vectors were perpendicular to each other, and the break of the pitched baseball became smaller as the angle between these vectors approached 0 degrees. Balls delivered from a pitching machine broke more than actual pitcher's balls. It is necessary to consider the differences when we use pitching machines in batting practice.

  16. STS-112 Flight Day 4 Highlights

    NASA Astrophysics Data System (ADS)

    2002-10-01

    On the fourth day of STS-112, its crew (Jeffrey Ashby, Commander; Pamela Melroy, Pilot; David Wolf, Mission Specialist; Piers Sellers, Mission Specialist; Sandra Magnus, Mission Specialist; Fyodor Yurchikhin, Mission Specialist) onboard Atlantis and the Expedition 5 crew (Valery Korzun, Commander; Peggy Whitson, Flight Engineer; Sergei Treschev, Flight Engineer) onboard the International Space Station (ISS) are seen preparing for the installation of the S1 truss structure. Inside the Destiny Laboratory Module, Korzun and other crewmembers are seen as they busily prepare for the work of the day. Sellers dons an oxygen mask and uses an exercise machine in order to purge the nitrogen from his bloodstream, in preparation for an extravehicular activity (EVA). Whitson uses the ISS's Canadarm 2 robotic arm to grapple the S1 truss and remove it from Atlantis' payload bay, with the assistance of Magnus. Using the robotic arm, Whitson slowly maneuvers the 15 ton truss structure into alignment with its attachment point on the starboard side of the S0 truss structure, where the carefully orchestrated mating procedures take place. There is video footage of the entire truss being rotated and positioned by the arm, and ammonia tank assembly on the structure is visible, with Earth in the background. Following the completion of the second stage capture, the robotic arm is ungrappled from truss. Sellers and Wolf are shown exiting the the Quest airlock hatch to begin their EVA. They are shown performing a variety of tasks on the now attached S1 truss structure, including work on the Crew Equipment Translation Cart (CETA), the S-band Antenna Assembly, and umbilical cables that provide power and remote operation capability to cameras. During their EVA, they are shown using a foot platform on the robotic arm. Significant portions of their activities are shown from the vantage of helmet mounted video cameras. The video closes with a final shot of the ISS and its new S1 truss.

  17. Pluto's plasma wake oriented away from the ecliptic plane

    NASA Astrophysics Data System (ADS)

    Pérez-de-Tejada, H.; Durand-Manterola, H.; Reyes-Ruiz, M.; Lundin, R.

    2015-01-01

    Conditions similar to those observed in the solar wind interaction with Venus and Mars where there is a planetary atmosphere in the absence of a global intrinsic magnetic field may also be applicable to Pluto. With up to 24 μbars inferred for the Pluto atmosphere it is possible that the feeble solar photon radiation flux that reaches by its orbit, equivalent to ∼10-3 that at Earth, is sufficient to produce an ionization component that can be eroded by the solar wind. In view of the reduced solar wind density (∼10-3 with respect to that at 1 AU) that should be available by Pluto its total kinetic energy will be significantly smaller than that at Earth. However, the parameter values that are implied for the interaction process between the solar wind and the local upper ionosphere are sufficient to produce a plasma wake that should extend downstream from Pluto. In view of its low gravity force the plasma wake should have a wider cross-section than that in the Venus and Mars plasma environment. Since Pluto rotates with the axis tilted ∼30° away from the ecliptic plane the plasma wake will be influenced by a Magnus force that has a large component is the north-south solar polar direction. That force will be responsible for propelling the plasma wake with a component that can be directed away from that plane. It is estimated that transport of solar wind momentum to the upper Pluto's ionosphere implies rotation periods smaller than that of the solid body, and thus large values of the Magnus force that can increase the orientation of the plasma wake away from the ecliptic plane.

  18. STS-112 Flight Day 4 Highlights

    NASA Technical Reports Server (NTRS)

    2002-01-01

    On the fourth day of STS-112, its crew (Jeffrey Ashby, Commander; Pamela Melroy, Pilot; David Wolf, Mission Specialist; Piers Sellers, Mission Specialist; Sandra Magnus, Mission Specialist; Fyodor Yurchikhin, Mission Specialist) onboard Atlantis and the Expedition 5 crew (Valery Korzun, Commander; Peggy Whitson, Flight Engineer; Sergei Treschev, Flight Engineer) onboard the International Space Station (ISS) are seen preparing for the installation of the S1 truss structure. Inside the Destiny Laboratory Module, Korzun and other crewmembers are seen as they busily prepare for the work of the day. Sellers dons an oxygen mask and uses an exercise machine in order to purge the nitrogen from his bloodstream, in preparation for an extravehicular activity (EVA). Whitson uses the ISS's Canadarm 2 robotic arm to grapple the S1 truss and remove it from Atlantis' payload bay, with the assistance of Magnus. Using the robotic arm, Whitson slowly maneuvers the 15 ton truss structure into alignment with its attachment point on the starboard side of the S0 truss structure, where the carefully orchestrated mating procedures take place. There is video footage of the entire truss being rotated and positioned by the arm, and ammonia tank assembly on the structure is visible, with Earth in the background. Following the completion of the second stage capture, the robotic arm is ungrappled from truss. Sellers and Wolf are shown exiting the the Quest airlock hatch to begin their EVA. They are shown performing a variety of tasks on the now attached S1 truss structure, including work on the Crew Equipment Translation Cart (CETA), the S-band Antenna Assembly, and umbilical cables that provide power and remote operation capability to cameras. During their EVA, they are shown using a foot platform on the robotic arm. Significant portions of their activities are shown from the vantage of helmet mounted video cameras. The video closes with a final shot of the ISS and its new S1 truss.

  19. Pluto's Plasma Wake Oriented Away from the Ecliptic Plane

    NASA Astrophysics Data System (ADS)

    Perez De Tejada, H. A.; Durand-Manterola, H.; Lundin, R. N.; Reyes-Ruiz, M.

    2013-12-01

    Conditions similar to those observed in the solar wind interaction with Venus and Mars with a planetary atmosphere and in the absence of an intrinsic magnetic field should also be applicable to Pluto. With up to 24 μbars inferred for the Pluto atmosphere it is possible that the feeble solar photon radiation flux that reaches by its orbit, equivalent to ~10-3 of that at earth, is sufficient to produce an ionization component that can be eroded by the solar wind. In view of the reduced solar wind density (~ 10-3 with respect to that by 1 AU) that should be available by Pluto its kinetic energy will be significantly smaller than that by earth. However, the parameter values that are implied for the interaction process between the solar wind and the local upper ionosphere are sufficient to produce a plasma wake that should extend downstream from Pluto. In view of its low gravity force the plasma wake should have a wider cross-section than that in the Venus and Mars plasma environment. Since Pluto rotates with its rotational axis tilted close to its orbital plane the plasma wake will be influenced by a Magnus force that is nearly north-south oriented. That force will be responsible for propelling the plasma wake with a component that can be directed away from the ecliptic plane. It is estimated that transport of solar wind momentum to the upper Pluto's ionosphere implies rotation periods smaller than that of the solid body, and thus larger values of the Magnus force that can increase the orientation of the plasma wake away from the ecliptic plane.

  20. Gram-Positive Anaerobic Cocci

    PubMed Central

    Murdoch, D. A.

    1998-01-01

    Gram-positive anaerobic cocci (GPAC) are a heterogeneous group of organisms defined by their morphological appearance and their inability to grow in the presence of oxygen; most clinical isolates are identified to species in the genus Peptostreptococcus. GPAC are part of the normal flora of all mucocutaneous surfaces and are often isolated from infections such as deep organ abscesses, obstetric and gynecological sepsis, and intraoral infections. They have been little studied for several reasons, which include an inadequate classification, difficulties with laboratory identification, and the mixed nature of the infections from which they are usually isolated. Nucleic acid studies indicate that the classification is in need of radical revision at the genus level. Several species of Peptostreptococcus have recently been described, but others still await formal recognition. Identification has been based on carbohydrate fermentation tests, but most GPAC are asaccharolytic and use the products of protein degradation for their metabolism; the introduction of commercially available preformed enzyme kits affords a physiologically more appropriate method of identification, which is simple and relatively rapid and can be used in routine diagnostic laboratories. Recent reports have documented the isolation in pure culture of several species, notably Peptostreptococcus magnus, from serious infections. Studies of P. magnus have elucidated several virulence factors which correlate with the site of infection, and reveal some similarities to Staphylococcus aureus. P. micros is a strongly proteolytic species; it is increasingly recognized as an important pathogen in intraoral infections, particularly periodontitis, and mixed anaerobic deep-organ abscesses. Comparison of antibiotic susceptibility patterns reveals major differences between species. Penicillins are the antibiotics of choice, although some strains of P. anaerobius show broad-spectrum β-lactam resistance. PMID:9457430

  1. Key Brainstem Structures Activated during Hypoxic Exposure in One-day-old Mice Highlight Characteristics for Modeling Breathing Network in Premature Infants

    PubMed Central

    Joubert, Fanny; Loiseau, Camille; Perrin-Terrin, Anne-Sophie; Cayetanot, Florence; Frugière, Alain; Voituron, Nicolas; Bodineau, Laurence

    2016-01-01

    We mapped and characterized changes in the activity of brainstem cell groups under hypoxia in one-day-old newborn mice, an animal model in which the central nervous system at birth is particularly immature. The classical biphasic respiratory response characterized by transient hyperventilation, followed by severe ventilation decline, was associated with increased c-FOS immunoreactivity in brainstem cell groups: the nucleus of the solitary tract, ventral reticular nucleus of the medulla, retrotrapezoid/parafacial region, parapyramidal group, raphe magnus nucleus, lateral, and medial parabrachial nucleus, and dorsal subcoeruleus nucleus. In contrast, the hypoglossal nucleus displayed decreased c-FOS immunoreactivity. There were fewer or no activated catecholaminergic cells activated in the medulla oblongata, whereas ~45% of the c-FOS-positive cells in the dorsal subcoeruleus were co-labeled. Approximately 30% of the c-FOS-positive cells in the parapyramidal group were serotoninergic, whereas only a small portion were labeled for serotonin in the raphe magnus nucleus. None of the c-FOS-positive cells in the retrotrapezoid/parafacial region were co-labeled for PHOX2B. Thus, the hypoxia-activated brainstem neuronal network of one-day-old mice is characterized by (i) the activation of catecholaminergic cells of the dorsal subcoeruleus nucleus, a structure implicated in the strong depressive pontine influence previously reported in the fetus but not in newborns, (ii) the weak activation of catecholaminergic cells of the ventral reticular nucleus of the medulla, an area involved in hypoxic hyperventilation, and (iii) the absence of PHOX2B-positive cells activated in the retrotrapezoid/parafacial region. Based on these results, one-day-old mice could highlight characteristics for modeling the breathing network of premature infants. PMID:28018238

  2. Electron dynamics in complex environments with real-time time dependent density functional theory in a QM-MM framework.

    PubMed

    Morzan, Uriel N; Ramírez, Francisco F; Oviedo, M Belén; Sánchez, Cristián G; Scherlis, Damián A; Lebrero, Mariano C González

    2014-04-28

    This article presents a time dependent density functional theory (TDDFT) implementation to propagate the Kohn-Sham equations in real time, including the effects of a molecular environment through a Quantum-Mechanics Molecular-Mechanics (QM-MM) hamiltonian. The code delivers an all-electron description employing Gaussian basis functions, and incorporates the Amber force-field in the QM-MM treatment. The most expensive parts of the computation, comprising the commutators between the hamiltonian and the density matrix-required to propagate the electron dynamics-, and the evaluation of the exchange-correlation energy, were migrated to the CUDA platform to run on graphics processing units, which remarkably accelerates the performance of the code. The method was validated by reproducing linear-response TDDFT results for the absorption spectra of several molecular species. Two different schemes were tested to propagate the quantum dynamics: (i) a leap-frog Verlet algorithm, and (ii) the Magnus expansion to first-order. These two approaches were confronted, to find that the Magnus scheme is more efficient by a factor of six in small molecules. Interestingly, the presence of iron was found to seriously limitate the length of the integration time step, due to the high frequencies associated with the core-electrons. This highlights the importance of pseudopotentials to alleviate the cost of the propagation of the inner states when heavy nuclei are present. Finally, the methodology was applied to investigate the shifts induced by the chemical environment on the most intense UV absorption bands of two model systems of general relevance: the formamide molecule in water solution, and the carboxy-heme group in Flavohemoglobin. In both cases, shifts of several nanometers are observed, consistently with the available experimental data.

  3. Three-dimensional modular control of human walking.

    PubMed

    Allen, Jessica L; Neptune, Richard R

    2012-08-09

    Recent studies have suggested that complex muscle activity during walking may be controlled using a reduced neural control strategy organized around the co-excitation of multiple muscles, or modules. Previous computer simulation studies have shown that five modules satisfy the sagittal-plane biomechanical sub-tasks of 2D walking. The present study shows that a sixth module, which contributes primarily to mediolateral balance control and contralateral leg swing, is needed to satisfy the additional non-sagittal plane demands of 3D walking. Body support was provided by Module 1 (hip and knee extensors, hip abductors) in early stance and Module 2 (plantarflexors) in late stance. In early stance, forward propulsion was provided by Module 4 (hamstrings), but net braking occurred due to Modules 1 and 2. Forward propulsion was provided by Module 2 in late stance. Module 1 accelerated the body medially throughout stance, dominating the lateral acceleration in early stance provided by Modules 4 and 6 (adductor magnus) and in late stance by Module 2, except near toe-off. Modules 3 (ankle dorsiflexors, rectus femoris) and 5 (hip flexors and adductors except adductor magnus) accelerated the ipsilateral leg forward in early swing whereas Module 4 decelerated the ipsilateral leg prior to heel-strike. Finally, Modules 1, 4 and 6 accelerated the contralateral leg forward prior to and during contralateral swing. Since the modules were based on experimentally measured muscle activity, these results provide further evidence that a simple neural control strategy involving muscle activation modules organized around task-specific biomechanical functions may be used to control complex human movements.

  4. A review of the genus Neoechinorhynchus (Acanthocephala:Neoechinorhynchidae) from Australia with the description of two new species.

    PubMed

    Smales, L R

    2013-12-01

    Abstract Eight species of Neoechinorhynchus were reported from Australian waters. Neoechinorhynchus vittiformis n. sp. is described from Eleutheronema tetradactylum (Shaw). It can be distinguished from all its congeners by the following combination of characters: long cylindrical trunk without cuticular plaques, globular proboscis, proboscis armature with the anterior circle of hooks larger with simple roots and the middle and posterior hooks the same size and smaller, short neck, lemnisci nearly equal, almost reaching the anterior testis which is more than half the length of the posterior testis. Neoechinorhynchus (Neoechinorhynchus) bryanti n. sp., described from Liza subviridis (Valenciennes), also with an elongated trunk, can be distinguished from its congeners by the combination of a wider anterior trunk without cuticular plaques, a relatively long conical neck, a subglobular proboscis having anterior hooks with manubria, the hooks becoming gradually smaller posteriorly, the lemnisci not reaching level of testes and the anterior testis being longer than posterior testis. Neoechinorhynchus sp. resembled Neoechinorhynchus aldrichettae Edmonds, 1971 but had a rectangular-shaped proboscis with larger anterior hooks. New host and locality records were presented for N. aldrichettae, Neoechinorhynchus (Hebesoma) agilis (Rudolphi) and Neoechinorhynchus tylosuri Yamaguti, 1939 . No additional specimens of either Neoechinorhynchus ningalooensis Pichelin and Cribb, 2001 or the species inquirenda, Neoechinorhynchus magnus Southwell and Macfie, 1925, were available for study. Of the 8 putative species listed here, 5 (N. [N.] bryanti, N. magnus , N. ningalooensis, N. vittiformis, and Neoechinorhynchus sp.) are endemic to Australian waters. By comparison with the North American fauna the Australian fauna was considered impoverished. The morphological and zoogeographical similarities within the group of 8 long, slender neoechinorhynchid species found in the African, Indo

  5. Shapiro steps for skyrmion motion on a washboard potential with longitudinal and transverse ac drives

    NASA Astrophysics Data System (ADS)

    Reichhardt, C.; Reichhardt, C. J. Olson

    2015-12-01

    We numerically study the behavior of two-dimensional skyrmions in the presence of a quasi-one-dimensional sinusoidal substrate under the influence of externally applied dc and ac drives. In the overdamped limit, when both dc and ac drives are aligned in the longitudinal direction parallel to the direction of the substrate modulation, the velocity-force curves exhibit classic Shapiro step features when the frequency of the ac drive matches the washboard frequency that is dynamically generated by the motion of the skyrmions over the substrate, similar to previous observations in superconducting vortex systems. In the case of skyrmions, the additional contribution to the skyrmion motion from a nondissipative Magnus force shifts the location of the locking steps to higher dc drives, and we find that the skyrmions move at an angle with respect to the direction of the dc drive. For a longitudinal dc drive and a perpendicular or transverse ac drive, the overdamped system exhibits no Shapiro steps; however, when a finite Magnus force is present, we find pronounced transverse Shapiro steps along with complex two-dimensional periodic orbits of the skyrmions in the phase-locked regimes. Both the longitudinal and transverse ac drives produce locking steps whose widths oscillate with increasing ac drive amplitude. We examine the role of collective skyrmion interactions and find that additional fractional locking steps occur for both longitudinal and transverse ac drives. At higher skyrmion densities, the system undergoes a series of dynamical order-disorder transitions, with the skyrmions forming a moving solid on the phase locking steps and a fluctuating dynamical liquid in regimes between the steps.

  6. Persistent inflammation-induced up-regulation of brain-derived neurotrophic factor (BDNF) promotes synaptic delivery of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor GluA1 subunits in descending pain modulatory circuits.

    PubMed

    Tao, Wenjuan; Chen, Quan; Zhou, Wenjie; Wang, Yunping; Wang, Lu; Zhang, Zhi

    2014-08-08

    The enhanced AMPA receptor phosphorylation at GluA1 serine 831 sites in the central pain-modulating system plays a pivotal role in descending pain facilitation after inflammation, but the underlying mechanisms remain unclear. We show here that, in the rat brain stem, in the nucleus raphe magnus, which is a critical relay in the descending pain-modulating system of the brain, persistent inflammatory pain induced by complete Freund adjuvant (CFA) can enhance AMPA receptor-mediated excitatory postsynaptic currents and the GluA2-lacking AMPA receptor-mediated rectification index. Western blot analysis showed an increase in GluA1 phosphorylation at Ser-831 but not at Ser-845. This was accompanied by an increase in distribution of the synaptic GluA1 subunit. In parallel, the level of histone H3 acetylation at bdnf gene promoter regions was reduced significantly 3 days after CFA injection, as indicated by ChIP assays. This was correlated with an increase in BDNF mRNA levels and BDNF protein levels. Sequestering endogenous extracellular BDNF with TrkB-IgG in the nucleus raphe magnus decreased AMPA receptor-mediated synaptic transmission and GluA1 phosphorylation at Ser-831 3 days after CFA injection. Under the same conditions, blockade of TrkB receptor functions, phospholipase C, or PKC impaired GluA1 phosphorylation at Ser-831 and decreased excitatory postsynaptic currents mediated by GluA2-lacking AMPA receptors. Taken together, these results suggest that epigenetic up-regulation of BDNF by peripheral inflammation induces GluR1 phosphorylation at Ser-831 sites through activation of the phospholipase C-PKC signaling cascade, leading to the trafficking of GluA1 to pain-modulating neuronal synapses.

  7. Systematic revision of the family Hoplitomerycidae Leinders, 1984 (Artiodactyla: Cervoidea), with the description of a new genus and four new species.

    PubMed

    Van der Geer, Alexandra A E

    2014-08-06

    Six species of the cervoid genus Hoplitomeryx are currently recognized from the Late Miocene sites of Gargano and Scontrone, in Italy: H. matthei Leinders, 1984, H. apruthiensis Mazza & Rustioni, 2011, H. apulicus Mazza & Rustioni, 2011, H. falcidens Mazza & Rustioni, 2011, H. magnus Mazza & Rustioni, 2011, and H. minutus Mazza & Rustioni, 2011. These species are interpreted as members of an anagenetic series in these two localities, which are considered as part of the same bioprovince but with different geological ages. Comparative analysis of postcranial, dental, and cranial material from Hoplitomerycidae resulted in the reinterpretation of this current taxonomic arrangement. Two distinct genera can be distinguished. The new genus Scontromeryx is restricted to Scontrone (Early Tortonian) and is characterised by the presence of second upper and lower premolars and the absence of a nasal (median) horn. Hoplitomeryx is restricted to Gargano (Middle and/or Late Tortonian), and is characterized by the loss of the second premolar and presence of a nasal horn. Both genera are characterized by orbital appendages in some species, but the morphology of these appendages differs between the genera. Six species can be recognized for Scontromeryx gen. n.: S. minutus (type species), S. falcidens, S. apulicus, S. apruthiensis, S. magnus (new combinations) and the newly described S. mazzai sp. n.. Hoplitomeryx is represented by the H. matthei (type species) and 3 newly described species H. devosi sp. n., H. macpheei sp. n. and H. kriegsmani sp. n.. These two multispecies assemblages are best explained as independent adaptive radiations with the two genera as sister taxa. There is no evidence that the two localities were connected during the Late Miocene.

  8. Electron dynamics in complex environments with real-time time dependent density functional theory in a QM-MM framework

    SciTech Connect

    Morzan, Uriel N.; Ramírez, Francisco F.; Scherlis, Damián A. E-mail: mcgl@qb.ffyb.uba.ar; Lebrero, Mariano C. González E-mail: mcgl@qb.ffyb.uba.ar

    2014-04-28

    This article presents a time dependent density functional theory (TDDFT) implementation to propagate the Kohn-Sham equations in real time, including the effects of a molecular environment through a Quantum-Mechanics Molecular-Mechanics (QM-MM) hamiltonian. The code delivers an all-electron description employing Gaussian basis functions, and incorporates the Amber force-field in the QM-MM treatment. The most expensive parts of the computation, comprising the commutators between the hamiltonian and the density matrix—required to propagate the electron dynamics—, and the evaluation of the exchange-correlation energy, were migrated to the CUDA platform to run on graphics processing units, which remarkably accelerates the performance of the code. The method was validated by reproducing linear-response TDDFT results for the absorption spectra of several molecular species. Two different schemes were tested to propagate the quantum dynamics: (i) a leap-frog Verlet algorithm, and (ii) the Magnus expansion to first-order. These two approaches were confronted, to find that the Magnus scheme is more efficient by a factor of six in small molecules. Interestingly, the presence of iron was found to seriously limitate the length of the integration time step, due to the high frequencies associated with the core-electrons. This highlights the importance of pseudopotentials to alleviate the cost of the propagation of the inner states when heavy nuclei are present. Finally, the methodology was applied to investigate the shifts induced by the chemical environment on the most intense UV absorption bands of two model systems of general relevance: the formamide molecule in water solution, and the carboxy-heme group in Flavohemoglobin. In both cases, shifts of several nanometers are observed, consistently with the available experimental data.

  9. Electron dynamics in complex environments with real-time time dependent density functional theory in a QM-MM framework

    NASA Astrophysics Data System (ADS)

    Morzan, Uriel N.; Ramírez, Francisco F.; Oviedo, M. Belén; Sánchez, Cristián G.; Scherlis, Damián A.; Lebrero, Mariano C. González

    2014-04-01

    This article presents a time dependent density functional theory (TDDFT) implementation to propagate the Kohn-Sham equations in real time, including the effects of a molecular environment through a Quantum-Mechanics Molecular-Mechanics (QM-MM) hamiltonian. The code delivers an all-electron description employing Gaussian basis functions, and incorporates the Amber force-field in the QM-MM treatment. The most expensive parts of the computation, comprising the commutators between the hamiltonian and the density matrix—required to propagate the electron dynamics—, and the evaluation of the exchange-correlation energy, were migrated to the CUDA platform to run on graphics processing units, which remarkably accelerates the performance of the code. The method was validated by reproducing linear-response TDDFT results for the absorption spectra of several molecular species. Two different schemes were tested to propagate the quantum dynamics: (i) a leap-frog Verlet algorithm, and (ii) the Magnus expansion to first-order. These two approaches were confronted, to find that the Magnus scheme is more efficient by a factor of six in small molecules. Interestingly, the presence of iron was found to seriously limitate the length of the integration time step, due to the high frequencies associated with the core-electrons. This highlights the importance of pseudopotentials to alleviate the cost of the propagation of the inner states when heavy nuclei are present. Finally, the methodology was applied to investigate the shifts induced by the chemical environment on the most intense UV absorption bands of two model systems of general relevance: the formamide molecule in water solution, and the carboxy-heme group in Flavohemoglobin. In both cases, shifts of several nanometers are observed, consistently with the available experimental data.

  10. [Renowned scientist, pedagogue, and physician dedicated to the memory of the 110th anniversary of Bronius Sidaravicius's birth].

    PubMed

    Laurynaityte, Gryta; Lignugariene, Asta; Valiukeviciene, Skaidra

    2007-01-01

    This year we celebrate the 110th anniversary of Bronius Sidaravicius's (1897-1969) birth. He was a renowned Lithuanian dermato-venereologist, professor, head of the Department of Skin and Venereal Diseases at Vytautas Magnus University (1935-1946, 1956-1969), the founder and the chair of the Lithuanian Society of Dermato-venereologists, coeditor of the prewar journal "Medicina." He is an author of more than 100 articles and the very first course book on dermato-venereology in Lithuanian. He completed a part of his medical studies at universities in Germany. In Vienna University (1930), B. Sidaravicius performed clinical and experimental studies on the passive transmission of skin allergy, which had a major impact on the diagnostics of allergic skin diseases and specific desensibilization. He published the results of his study in the foreign literature and in the doctoral dissertation "Skin allergy and its treatment" in 1931. Thanks to the efforts of B. Sidaravicius and his colleagues, a progressive Law on Control and Prevention of Venereal Diseases was enacted in Lithuania. According to this Law, examinations and treatment of venereal diseases became compulsory and free of charge at state- or municipality-financed venereal outpatient units. This article was prepared on the basis of primary sources: protocols of the Council (the Faculty of Medicine, the University of Lithuania; since 1930 - Vytautas Magnus University) kept at the Museum of the History of Lithuania Medicine and Pharmacy as well as documents preserved at the Lithuanian State Archives and also scientific journals and periodicals both in Lithuanian and foreign languages.

  11. Fluid Mechanics of Cricket and Tennis Balls

    NASA Astrophysics Data System (ADS)

    Mehta, Rabindra D.

    2009-11-01

    Aerodynamics plays a prominent role in defining the flight of a ball that is struck or thrown through the air in almost all ball sports. The main interest is in the fact that the ball can often deviate from its initial straight path, resulting in a curved, or sometimes an unpredictable, flight path. It is particularly fascinating that that not all the parameters that affect the flight of a ball are always under human influence. Lateral deflection in flight, commonly known as swing, swerve or curve, is well recognized in cricket and tennis. In tennis, the lateral deflection is produced by spinning the ball about an axis perpendicular to the line of flight, which gives rise to what is commonly known as the Magnus effect. It is now well recognized that the aerodynamics of sports balls are strongly dependent on the detailed development and behavior of the boundary layer on the ball's surface. A side force, which makes a ball curve through the air, can also be generated in the absence of the Magnus effect. In one of the cricket deliveries, the ball is released with the seam angled, which trips the laminar boundary layer into a turbulent state on that side. The turbulent boundary layer separates relatively late compared to the laminar layer on the other side, thereby creating a pressure difference and hence side force. The fluid mechanics of a cricket ball become very interesting at the higher Reynolds numbers and this will be discussed in detail. Of all the round sports balls, a tennis ball has the highest drag coefficient. This will be explained in terms of the contribution of the ``fuzz" drag and how that changes with Reynolds number and ball surface wear. It is particularly fascinating that, purely through historical accidents, small disturbances on the ball surface, such as the stitching on cricket balls and the felt cover on tennis balls are all about the right size to affect boundary layer transition and development in the Reynolds numbers of interest. The fluid

  12. Alternate arrangement of PpL B3 domain and SpA D domain creates synergistic double-site binding to VH3 and Vkappa regions of fab.

    PubMed

    Jiang, Shaohua H; Wang, Jufang F; Xu, Rong; Liu, Yanjun J; Wang, Xiaoning N; Cao, Jie; Zhao, Ping; Shen, Yijun J; Yang, Tong; Yang, Hua; Jia, Jiaan A; Chen, Qiuli L; Pan, Wei

    2008-08-01

    In our previous study, a kind of novel hybrid immunoglobulin (Ig)-binding proteins (IBPs) was obtained with the characteristic structure of alternately arranged Finegoldia magna (formerly Peptostreptococcus magnus) protein L (P. magnus protein L, PpL) B3 domain (B3) and Staphylococcal protein A (SpA) D domain (D). In this study, two representative molecules of these novel proteins, LD3 (B3-D-B3) and LD5 (B3-D-B3-D-B3) (LD3/5), showed substantially higher affinity for IgG-F(ab')2, IgM, and IgA than 4L (B3-B3-B3-B3) or SpA, which were also demonstrated by surface plasmon resonance detection. Further, LD5 showed much stronger binding to single-chain Fv (scFv) KM38 (V(H)3-V(kappa)I) than to KM41 (V(H)1-V(kappa)III) or KM36 (V(H)3-V(kappa)III). Competitive inhibition studies showed that 4L alone or in combination with SpA (4L + SpA) was a weaker inhibitor than LD3/5 in inhibiting LD3/5's binding to IgG-F(ab')2, IgM, or IgA. The computer modeling suggested that the B3-D arrangement in LD3/5 could simultaneously bind to V(H)3 and V(kappa). Thus, our results indicated for the first time that alternate arrangement of B3 and D domains creates synergistic double-site binding to V(H)3 and V(kappa) regions of fragment of antigen binding. The different competitive inhibition pattern of binding of LD5 to scFv KM38 by 4L + SpA suggested strict use of antibody conformation for this simultaneous double-site binding. The demonstration of this novel binding property would promote to achieve the designed hybrid IBPs for useful immunological applications.

  13. Acute flesinoxan treatment produces a different effect on rat brain serotonin synthesis than chronic treatment: an alpha-methyl-l-tryptophan autoradiographic study.

    PubMed

    Tohyama, Yoshihiro; Mück-Seler, Dorotea; Diksic, Mirko

    2007-12-01

    5-HT(1A) receptor agonists display anxiolytic and anti-depressant properties in clinical studies. In this study, we used the alpha-[(14)C]methyl-l-tryptophan (alpha-MTrp) autoradiographic method to evaluate the effects of the 5-HT(1A) agonist, flesinoxan, on regional 5-HT synthesis in the rat brain, following acute or a 14-day continuous treatment. In the first series of experiments, flesinoxan (5mg/kg; i.p.) was administered 40min before the alpha-MTrp. It resulted in a significant increase of the arterial blood oxygen partial pressure (pO(2)) and a reduction of the regional rate of 5-HT synthesis throughout the brain, with the exception of a few regions (medial geniculate body and thalamus). In the second series of experiments, flesinoxan (5mg/kgday) was administered for 14 days, using an osmotic minipump implanted subcutaneously. When compared to rats treated with saline, there was an overall significant (p<0.05) reduction in the synthesis (one-sample two-tailed t-test). However, there was no significant influence on the 5-HT synthesis rate in the dorsal and median raphe nuclei and the majority of their projection areas. A significant (p<0.05) reduction was observed in the nucleus raphe magnus, medial caudate, ventral thalamus, amygdala, ventral tegmental area, medial forebrain bundle, nucleus accumbens, medial anterior olfactory nucleus and superior olive. The unaltered 5-HT synthesis rates in a large majority of regions following the 14-day treatment of flesinoxan may reflect the normalization (implies to not be different from salne treated control) of synthesis due to a desensitization of 5-HT(1A) autoreceptors on the cell body of 5-HT neurons as well as at postsynaptic sites, which is known to occur following long-term treatment with 5-HT(1A) agonists. It is of some importance to note that the normalization of the synthesis occurred in the majority of the brain limbic structures, the brain areas implicated in affective disorders and the corresponding

  14. Neuroanatomical approaches of the tectum-reticular pathways and immunohistochemical evidence for serotonin-positive perikarya on neuronal substrates of the superior colliculus and periaqueductal gray matter involved in the elaboration of the defensive behavior and fear-induced analgesia.

    PubMed

    Coimbra, N C; De Oliveira, R; Freitas, R L; Ribeiro, S J; Borelli, K G; Pacagnella, R C; Moreira, J E; da Silva, L A; Melo, L L; Lunardi, L O; Brandão, M L

    2006-01-01

    in the pontine reticular formation, gigantocellularis nucleus, and nucleus raphe magnus. The midbrain tectum-gigantocellularis complex and midbrain tectum-nucleus raphe magnus neural pathways may provide an alternative output allowing the organization of the fear-induced anti-nociception by mesencephalic networks.

  15. Crustal composition in southern Norway from active and passive source seismology

    NASA Astrophysics Data System (ADS)

    Stratford, W. R.; Frassetto, A. M.; Thybo, H.

    2010-12-01

    Crustal composition and structure beneath the Fennoscandian shield are highly variable due to the method of crustal accretion and the long history of extensional and compressional tectonics. In southern Norway, the Moho and crust are inferred to be the youngest of the shield, however, it is likely that a large discrepancy between crustal age and Moho age exists beneath the high southern Scandes where the Caledonian orogeny was in effect and beneath the Oslo Graben where 60 million years of rifting and magmatism has altered the crust. Crustal structure in southern Norway was targeted with a multi-disciplinary seismic study (Magnus-Rex - Mantle investigations of Norwegian uplift Structure). Three ~400 km long active source seismic profiles across the southern Norway and a region wide array of broadband seismometers were deployed. P and S-wave arrivals were recorded in the Magnus-Rex project, from which Poisson ratios for the crust in southern Norway are calculated from both active source profiling and receiver functions. Unusually strong S-wave arrivals allow rare insight into crustal Poisson’s ratio structure, within crustal layers, that is not normally available from active source data and are usually determined by earthquake tomography studies where only bulk crustal values are available. An average Poisson’s ratio of 0.25 is calculated for the crust in southern Norway, suggesting it is predominantly of felsic-intermediate composition and lacks any significant mafic lower crust. This differs significantly from the adjacent crust in the Svecofennian domain of the Fennoscandian shield where Moho depths reach ~50 km and an up to 20 km thick mafic lower crust is present. The vast difference in Moho depths in the Fennoscandian shield are, therefore, mostly due to the variation in thickness of the high Vp lower crust. Estimates of crustal composition and the effect of Magma intrusion within the Oslo Graben, and possible delamination of the lowermost crust beneath

  16. Muscle contributions to frontal plane angular momentum during walking.

    PubMed

    Neptune, Richard R; McGowan, Craig P

    2016-09-06

    The regulation of whole-body angular momentum is important for maintaining dynamic balance during human walking, which is particularly challenging in the frontal plane. Whole-body angular momentum is actively regulated by individual muscle forces. Thus, understanding which muscles contribute to frontal plane angular momentum will further our understanding of mediolateral balance control and has the potential to help diagnose and treat balance disorders. The purpose of this study was to identify how individual muscles and gravity contribute to whole-body angular momentum in the frontal plane using a muscle-actuated forward dynamics simulation analysis. A three-dimensional simulation was developed that emulated the average walking mechanics of a group of young healthy adults (n=10). The results showed that a finite set of muscles are the primary contributors to frontal plane balance and that these contributions vary throughout the gait cycle. In early stance, the vasti, adductor magnus and gravity acted to rotate the body towards the contralateral leg while the gluteus medius acted to rotate the body towards the ipsilateral leg. In late stance, the gluteus medius continued to rotate the body towards the ipsilateral leg while the soleus and gastrocnemius acted to rotate the body towards the contralateral leg. These results highlight those muscles that are critical to maintaining dynamic balance in the frontal plane during walking and may provide targets for locomotor therapies aimed at treating balance disorders.

  17. [High prevalence and diversity of blood parasites of passerine birds in Southern Turkmenistan].

    PubMed

    Val'kiunas, G; Ezhova, T A; Mironov, S V

    2001-01-01

    Thirty nine specimens of passerine birds belonging to 19 species and eight families were investigated by blood smear technique in four localities of Southern Turkmenistan in 3-18 August 1991. The overall prevalence of infection was 59%. Protists from the orders Haemosporida (genera Haemoproteus, Plasmodium, Leucocytozoon), Kinetoplastida (Trypanosoma), and Adeleida (Hepatozoon), as well as Microfilaria were found. Haemoproteids (the prevalence of infection is 44%), leucocytozoids (23%), malarial parasites (13%) and trypanosomes (13%) were most frequently recorded. Only low chronic infections (< 1% of infected cells for the great majority of intracellular parasites, and a few trypanosomes and Microfilaria in each blood smear) were seen. Haemoproteus belopolskyi, H. balmorali, H. dolniki, H. magnus, H. minutus, H. fringillae, H. majoris, Leucocytozoon dubreuili, and Trypanosoma avium were recorded for the first time in Turkmenistan. The former five above-mentioned species of haemoproteids are new records for the fauna of Middle Asia. Gametocytes of leucocytozoids in fusiform host cells were found for the first time in passerine birds in the Holarctic. The host is Parus bokharensis. Due to the wide distribution and the opportunity to collect a large parasitological material using harmless for hosts methods, bird haemosporidian parasites can be used as convenient models for ecological and evolutionary biology studies in South Turkmenistan. The heavily infected Orphean Warbler Sylvia hortensis is an especially convenient host for such purposes.

  18. The effect of spin on the flight of a baseball

    NASA Astrophysics Data System (ADS)

    Nathan, Alan M.

    2008-02-01

    Measurements are presented of the Magnus force on a spinning baseball. The experiment utilizes a pitching machine to project the baseball horizontally, a high-speed motion analysis system to determine the initial velocity and angular velocity and to track the trajectory over 5m of flight, and a ruler to measure the total distance traversed. Speeds in the range v =50-110mph and spin rates ω (topspin or backspin) in the range 1500-4500rpm were utilized, corresponding to Reynolds numbers of Re =(1.1-2.4)×105 and spin factors S ≡Rω/v in the range 0.090-0.595. Least-squares fits were used to extract the initial parameters of the trajectory and to determine the lift coefficients. Comparison is made with previous measurements and parametrizations, and implications for the effect of spin on the flight of a baseball are discussed. The lift coefficient CL is found not to depend strongly on v at fixed values of S.

  19. Exfoliative cytology of buccal squames: A quantitative cytomorphometric analysis of patients with diabetes

    PubMed Central

    Sankhla, Bharat; Sharma, Abhishek; Shetty, Raju Singam; Bolla, Sheetal Chowdary; Gantha, Naga Sribala; Reddy, Prasun

    2014-01-01

    Background: Diabetes is a third leading cause of mortality and morbidity in the world. Diabetes is one of the most common endocrine metabolic disorders and its prevalence has been increasing worldwide. Oral exfoliative cytology may be a more appropriate adjunctive diagnostic tool in conditions like diabetes mellitus, where the invasive techniques lose viability. Aims: The purpose of this study is to analyze the cytomorphometric changes in the exfoliated cells of the oral mucosa, as an adjunct to the diagnosis of diabetes. Materials and Methods: Smears were taken from the buccal mucosa of 30 diabetes patients (study group) and 30 healthy individuals (control group). All the smears were stained with rapid Papanicolaou stain (PAP). In the PAP smears, the nuclear area (NA), cytoplasmic area (CA), and cytoplasmic-to-nuclear ratio (CNR) were evaluated for 50 cells in each smear, using the Image Analysis Software (Magnus Pro™) and research microscope (Lawrence and Mayo™). Results: The results showed that the mean NA was significantly higher (P < 0.001) in the study group, whereas, the mean CA did not exhibit a statistically significant difference (P > 0.001). The mean CNR was significantly lower in the study group (P < 0.001). Interpretation and Conclusion: The results associated with the clinical observations suggest that diabetes can produce morphological and functional alterations in the oral epithelial cells, detectable by microscopic and cytomorphometric analysis using exfoliative cytology, which can be used in the diagnosis of the disease. PMID:25374837

  20. Large Eddy Simulation of Transient Flow, Solidification, and Particle Transport Processes in Continuous-Casting Mold

    NASA Astrophysics Data System (ADS)

    Liu, Zhongqiu; Li, Linmin; Li, Baokuan; Jiang, Maofa

    2014-07-01

    The current study developed a coupled computational model to simulate the transient fluid flow, solidification, and particle transport processes in a slab continuous-casting mold. Transient flow of molten steel in the mold is calculated using the large eddy simulation. An enthalpy-porosity approach is used for the analysis of solidification processes. The transport of bubble and non-metallic inclusion inside the liquid pool is calculated using the Lagrangian approach based on the transient flow field. A criterion of particle entrapment in the solidified shell is developed using the user-defined functions of FLUENT software (ANSYS, Inc., Canonsburg, PA). The predicted results of this model are compared with the measurements of the ultrasonic testing of the rolled steel plates and the water model experiments. The transient asymmetrical flow pattern inside the liquid pool exhibits quite satisfactory agreement with the corresponding measurements. The predicted complex instantaneous velocity field is composed of various small recirculation zones and multiple vortices. The transport of particles inside the liquid pool and the entrapment of particles in the solidified shell are not symmetric. The Magnus force can reduce the entrapment ratio of particles in the solidified shell, especially for smaller particles, but the effect is not obvious. The Marangoni force can play an important role in controlling the motion of particles, which increases the entrapment ratio of particles in the solidified shell obviously.

  1. [Nazi Terror against the Danish Medical Profession. The February 20, 1945 Murders in Odense].

    PubMed

    Jeune, Bernard; Hess, Søren; Skytthe, Axel; Stræde, Therkel

    2015-01-01

    On February 20, 1945, during the German occupation of Denmark, members of a notorious Nazi terror organization named the Petergroup murdered four young medical doctors at the city and regional hospital of Odense. On the 70th anniversary of the crime, a symposium was organized at the Odense University Hospital, and a monument revealed close to the site of the murders in commemoration of the four victims of the crime. The young physicians were not known to be connected with the Danish resistance, and they were shot without their murderers even knowing their identities in an attempt to revenge the growing resistance in Denmark's central, third largest city, and as a reprisal for several cases where the hospital had treated wounded resistance fighters, and prevented their being handed over to the German police. The article describes the terror action of February 20, 1945 and its perpetrators, as well as other Nazi attacks on members of the Danish medical profession. It lines out the strong protest voiced by the Danish central administration against the Odense hospital killings which were on the very same day seconded by further killings and a German campaign of blowing up important Odense buildings including two newspaper printing houses. Conclusively, the authors - by way of obituaries and material from relatives of the murdered - portray the four victims of the atrocity Christian Fabricius Møller, Jørgen Hvalkof, Henning Magnus Adelsteen Dalsgaard, and Henning Ørsberg.

  2. Editorial

    NASA Astrophysics Data System (ADS)

    2005-01-01

    COSIRES 2004 was the seventh conference in the series of international conferences on computer simulation of radiation effects in solids. This series started in 1992 in Berlin, Germany, and has since then been held biennially in Santa Barbara, USA; Guildford, UK; Okayama, Japan; State College, USA and Dresden, Germany. In 2004 we were pleased to host 104 persons in Helsinki. The strength of the conference series was reflected in that about half of the attendees were graduate students or young postdocs. The good attendance and success of the meeting was to a large extent made possible by generous financial support from the Academy of Finland, the University of Helsinki, the Vilho, Yrjö and Kalle Väisälä foundation and the Magnus Ehrnrooth foundation. I am very grateful for this support received, as well as the efforts put in for the meeting by the international advisory committee, program committee and most of all the local organizing committee. Without the help of all my 18 local co-organizers the meeting could not have ran as smoothly and pleasantly as it did.

  3. Toledo School of Translators and their influence on anatomical terminology.

    PubMed

    Arráez-Aybar, Luis-Alfonso; Bueno-López, José-L; Raio, Nicolas

    2015-03-01

    Translation facilitates transmission of knowledge between cultures. The fundamental transfer of anatomic terminology from the Ancient Greek and Islamic Golden Age cultures, to medieval Latin Christendom took place in the so-called Toledo School of Translators in the 12th-13th centuries. Translations made in Toledo circulated widely across Europe. They were the foundation of scientific thinking that was born in the boards of first universities. In Toledo, Gerard of Cremona translated Avicenna's Canon of Medicine, the key work of Islamic Golden Age of medicine. Albertus Magnus, Mondino de Luzzi and Guy de Chauliac, the leading authors of anatomical Latin words in the Middle Ages, founded their books on Gerard's translations. The anatomical terms of the Canon retain auctoritas up to the Renaissance. Thus, terms coined by Gerard such as diaphragm, orbit, pupil or sagittal remain relevant in the current official anatomical terminology. The aim of the present paper is to bring new attention to the highly significant influence that the Toledo School of Translators had in anatomical terminology. For this, we shall review here the onomastic origins of a number of anatomical terms (additamentum; coracoid process; coxal; false ribs; femur; panniculus; spondylus; squamous sutures; thorax; xiphoid process, etc.) which are still used today.

  4. Mid-Mesozoic flea-like ectoparasites of feathered or haired vertebrates.

    PubMed

    Gao, Tai-ping; Shih, Chung-kun; Xu, Xing; Wang, Shuo; Ren, Dong

    2012-04-24

    Parasite-host associations among insects and mammals or birds are well attended by neontological studies [1]. An Eocene bird louse compression fossil [2, 3] and several flea specimens from Eocene and Oligocene ambers [4-8], reported to date, are exceptionally similar to living louse and flea taxa. But the origin, morphology, and early evolution of parasites and their associations with hosts are poorly known [9, 10] due to sparse records of putative ectoparasites with uncertain classification in the Mesozoic, most lacking mouthpart information and other critical details of the head morphology [11-15]. Here we present two primitive flea-like species assigned to the Pseudopulicidae Gao, Shih et Ren familia nova (fam. nov.), Pseudopulex jurassicus Gao, Shih et Ren genus novum et species nova (gen. et sp. nov) from the Middle Jurassic [16] and P. magnus Gao, Shih et Ren sp. nov. from the Early Cretaceous in China [17]. They exhibit many features of ectoparasitic insects. Large body size and long serrated stylets for piercing tough and thick skin or hides of hosts suggest that these primitive ectoparasites might have lived on and sucked the blood of relatively large hosts, such as contemporaneous feathered dinosaurs and/or pterosaurs or medium-sized mammals (found in the Early Cretaceous, but not the Middle Jurassic).

  5. Selectivity in multiple quantum nuclear magnetic resonance

    SciTech Connect

    Warren, W.S.

    1980-11-01

    The observation of multiple-quantum nuclear magnetic resonance transitions in isotropic or anisotropic liquids is shown to give readily interpretable information on molecular configurations, rates of motional processes, and intramolecular interactions. However, the observed intensity of high multiple-quantum transitions falls off dramatically as the number of coupled spins increases. The theory of multiple-quantum NMR is developed through the density matrix formalism, and exact intensities are derived for several cases (isotropic first-order systems and anisotropic systems with high symmetry) to shown that this intensity decrease is expected if standard multiple-quantum pulse sequences are used. New pulse sequences are developed which excite coherences and produce population inversions only between selected states, even though other transitions are simultaneously resonant. One type of selective excitation presented only allows molecules to absorb and emit photons in groups of n. Coherent averaging theory is extended to describe these selective sequences, and to design sequences which are selective to arbitrarily high order in the Magnus expansion. This theory and computer calculations both show that extremely good selectivity and large signal enhancements are possible.

  6. The influence of meteorological factors on growth and vegetation process of Perilla frutescens (L.) Britton in Lithuania.

    PubMed

    Ragazinskiene, Ona; Seinauskiene, Erika; Janulis, Valdimaras; Jankauskaite, Lina; Milasius, Arvydas

    2006-01-01

    The results of a study on the dependence of growth and vegetation process of Perilla frutescens (L.) Britton upon meteorological factors are presented in the article. The investigations were conducted at Kaunas Botanical Garden of Vytautas Magnus University during vegetation periods in 2001-2005. The object of investigations was Perilla frutescens (L.) Britton, a medicinal annual herbaceous plant of Lamiaceae Lindl. family, native of Eastern Asia, which passes the whole development cycle under climatic conditions of Central Lithuania. The duration of vegetation period of Perilla frutescens on the average is 167 days. The earliest beginning of vegetation and optimal climatic conditions for growth are when hydrothermic coefficient reaches 1.60-1.80 (conditions of excessive humidity). Optimal climatic conditions for massive flowering and seed maturation are observed when hydrothermic coefficient decreases to 1.20 - then massive flowering starts 10 days earlier and lasts 25 days longer. A strong correlation was found between massive flowering and hydrothermic coefficient (r(2)=0.9408). Using mathematical-statistical methods, the consistent patterns of growth and vegetation process of Perilla frutescens (L.) Britton were determined, specifying the time for raw material preparation what determines its quality and quantity.

  7. Arthur Simons (1877-1942) and Tonic Neck Reflexes With Hemiplegic "Mitbewegungen" (Associated Reactions): Cinematography From 1916-1919.

    PubMed

    Holdorff, Bernd

    2016-01-01

    Tonic neck reflexes were investigated by Rudolf Magnus and Adriaan de Kleijn in animals and men in 1912 and eventually by Arthur Simons, a neurologist in Berlin and coworker of Hermann Oppenheim. Simons studied these reflexes in hemiplegic patients, who were mainly victims of World War I. This work became his most important contribution and remained unsurpassed for many years. The film (Filmarchiv, Bundesarchiv [Film Archive, National Archive] Berlin) with Simons as an examiner shows 11 war casualties with brain lesions that occurred between 1916 and 1919. The injuries reveal asymmetric neck reflexes with "Mitbewegungen," that is, flexion or extension on the hemiplegic side. Mitbewegungen is identical with Francis Walshe's "associated reactions" caused by neck rotation and/or by cocontraction of the nonaffected extremities, for example, by closing of the fist (Walshe). The knowledge of the neck reflexes is important in acute neurology and in rehabilitation therapy of hemiplegics for antispastic positions. Simons' investigations were conducted in the early era of increasing use of cinematography in medical studies. The film had been nearly forgotten until its rediscovery in 2010.

  8. Photoballistics of volcanic jet activity at Stromboli, Italy

    NASA Technical Reports Server (NTRS)

    Chouet, B.; Hamisevicz, N.; Mcgetchin, T. R.

    1974-01-01

    Two night eruptions of the volcano Stromboli were studied through 70-mm photography. Single-camera techniques were used. Particle sphericity, constant velocity in the frame, and radial symmetry were assumed. Properties of the particulate phase found through analysis include: particle size, velocity, total number of particles ejected, angular dispersion and distribution in the jet, time variation of particle size and apparent velocity distribution, averaged volume flux, and kinetic energy carried by the condensed phase. The frequency distributions of particle size and apparent velocities are found to be approximately log normal. The properties of the gas phase were inferred from the fact that it was the transporting medium for the condensed phase. Gas velocity and time variation, volume flux of gas, dynamic pressure, mass erupted, and density were estimated. A CO2-H2O mixture is possible for the observed eruptions. The flow was subsonic. Velocity variations may be explained by an organ pipe resonance. Particle collimation may be produced by a Magnus effect.

  9. Complex dynamics of defective interfering baculoviruses during serial passage in insect cells.

    PubMed

    Zwart, Mark P; Pijlman, Gorben P; Sardanyés, Josep; Duarte, Jorge; Januário, Cristina; Elena, Santiago F

    2013-03-01

    Defective interfering (DI) viruses are thought to cause oscillations in virus levels, known as the 'Von Magnus effect'. Interference by DI viruses has been proposed to underlie these dynamics, although experimental tests of this idea have not been forthcoming. For the baculoviruses, insect viruses commonly used for the expression of heterologous proteins in insect cells, the molecular mechanisms underlying DI generation have been investigated. However, the dynamics of baculovirus populations harboring DIs have not been studied in detail. In order to address this issue, we used quantitative real-time PCR to determine the levels of helper and DI viruses during 50 serial passages of Autographa californica multiple nucleopolyhedrovirus (AcMNPV) in Sf21 cells. Unexpectedly, the helper and DI viruses changed levels largely in phase, and oscillations were highly irregular, suggesting the presence of chaos. We therefore developed a simple mathematical model of baculovirus-DI dynamics. This theoretical model reproduced patterns qualitatively similar to the experimental data. Although we cannot exclude that experimental variation (noise) plays an important role in generating the observed patterns, the presence of chaos in the model dynamics was confirmed with the computation of the maximal Lyapunov exponent, and a Ruelle-Takens-Newhouse route to chaos was identified at decreasing production of DI viruses, using mutation as a control parameter. Our results contribute to a better understanding of the dynamics of DI baculoviruses, and suggest that changes in virus levels over passages may exhibit chaos.

  10. Subsonic Aerodynamics of Spinning and Non-Spinning Type 200 Lightcraft: Progress Report

    NASA Astrophysics Data System (ADS)

    Kenoyer, David A.; Myrabo, Leik N.

    2010-05-01

    A combined experimental and numerical investigation of subsonic aerodynamics for Type 200 laser lightcraft is underway for both spinning and non-spinning cases. A 12.2 cm diameter aluminum model with a "closed" annular airbreathing inlet was fitted to a sting balance in RPI's 61 cm by 61 cm subsonic wind tunnel. Aerodynamic forces and moments were measured first for the non-spinning case vs. angle of attack, at several freestream flow velocities (e.g., 30, 45, and 60 m/s) to assess Reynolds number effects. The CFD analysis was performed for 0-180° angles of attack for a fixed coordinate system (i.e., non-spinning Type 200 model), and predictions compared favorably with the experimental data. In the near future, for the spinning case, a brushless electric motor has been installed to rotate the wind tunnel model at 3000 to 13,000 RPM; Magnus force effects upon the coefficients (Cd, Cl, and Cm) are expected to reveal interesting departures from the non-spinning database in forthcoming experiments.

  11. MALDI-TOF MS for the identification of veterinary non-C. neoformans-C. gattii Cryptococcus spp. isolates from Italy.

    PubMed

    Danesi, Patrizia; Drigo, Ilenia; Iatta, Roberta; Firacative, Carolina; Capelli, Gioia; Cafarchia, Claudia; Meyer, Wieland

    2014-08-01

    Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) offers an effective alternative to phenotypic and molecular methods for the rapid identification of microorganisms. Our aim in this study was to create an in-house library for a set of strains of nine uncommonly reported human and animal cryptococcal species, including Cryptococcus adeliensis, C. albidosimilis, C. albidus, C. aureus, C. carnescens, C. laurentii, C. magnus, C. victoriae and C. uniguttulatus, and to use this library to make timely and correct identifications using MALDI-TOF MS for use in routine laboratory diagnostics. Protein extracts obtained via the formic acid extraction method of 62 veterinary non-C. neoformans-C. gattii cryptococcal isolates were studied. The obtained mass spectra correctly grouped all 62 studied isolates according to species identification previously obtained by internal transcribe spacer sequence analysis. The in-house database was than exported and successfully uploaded to the Microflex LT (Maldi Biotyper; Bruker Daltonics) instrument at a different diagnostic laboratory in Italy. Scores >2.7 obtained from isolates reanalyzed in the latter laboratory supported the high reproducibility of the method. The possibility of creating and transferring an in-house library adds to the usefulness MALDI-TOF MS an important tool for the rapid and inexpensive identification of pathogenic and saprophytic fungi as required for differential diagnosis of human and animal mycoses.

  12. The history and illustration of anatomy in the Middle Ages.

    PubMed

    Gurunluoglu, Raffi; Gurunluoglu, Aslin; Williams, Susan A; Cavdar, Safiye

    2013-11-01

    This article reviews the influence of key figures on the pictorial representation of anatomy and the evolution of anatomical illustration during the Middle Ages until the time of the Renaissance, based on medical history books, journals and ancient medical books. During the early period in the Middle Ages, most illustrations were traditional drawings of emblematic nature, oftentimes unrealistic, not only because the precise knowledge of anatomy was lacking but also because the objective was to elucidate certain principles for teaching purposes. Five figure-series that came down to us through ancient manuscripts and textbooks represent the best examples of such traditional illustrations. With the advent of human dissection in the 13th and 14th centuries, a significant transformation in the depiction of anatomy began to project the practice of human dissection, as we see in the works of Mondino de Luzzi, Henri de Mondeville and Guido de Vigevano. After the invention of book printing in the second half of the 15th century, the reproduction of books was commonly practised and the woodcut made multiplication of pictures easier. Peter of Abano, Hieronymous Brunschwig, Johannes de Ketham, Johannes Peyligk, Gregory Reisch, Magnus Hundt, Laurentius Phryesen and many more included several anatomical illustrations in their treatises that demonstrated the development of anatomical illustration during the later Middle Ages.

  13. STS-112 Mission Highlights Resource Tape, Part 1 of 3

    NASA Technical Reports Server (NTRS)

    2003-01-01

    This video, Part 1 of 3, shows the activities of the STS-112 crew on flight days 1 - 3. The crew included Commander Jeff Ashby, Pilot Pam Melroy, and Mission Specialists Sandy Magnus, David Wolf, Piers Sellers, and Fyodor Yurchikhin. Flight day 1 begins with an introduction of the astronauts, seen during their pre-flight banquet, and suit-up. The ingress of some of the crew into the Space Shuttle Atlantis is shown. The launch footage includes the view from a camera mounted on the shuttle's external fuel tank, as well as replays. The separation of the shuttle's booster rockets is also shown. On flight day 2 a view of the payload bay and orbiter docking mechanism on Atlantis is shown from a camera on the shuttle's robotic arm. The footage of flight day 3 includes the docking of Atlantis and the International Space Station (ISS), and the exchange of greetings between the two spacecrews. Views of Earth include a pass over the western United States on flight day 2, and a night view of China on flight day 3.

  14. Effective Hamiltonians for Rapidly Driven Many-Body Lattice Systems: Induced Exchange Interactions and Density-Dependent Hoppings

    NASA Astrophysics Data System (ADS)

    Itin, A. P.; Katsnelson, M. I.

    2015-08-01

    We consider 1D lattices described by Hubbard or Bose-Hubbard models, in the presence of periodic high-frequency perturbations, such as uniform ac force or modulation of hopping coefficients. Effective Hamiltonians for interacting particles are derived using an averaging method resembling classical canonical perturbation theory. As is known, a high-frequency force may renormalize hopping coefficients, causing interesting phenomena such as coherent destruction of tunneling and creation of artificial gauge fields. We find explicitly additional corrections to the effective Hamiltonians due to interactions, corresponding to nontrivial processes such as single-particle density-dependent tunneling, correlated pair hoppings, nearest neighbor interactions, etc. Some of these processes arise also in multiband lattice models, and are capable of giving rise to a rich variety of quantum phases. The apparent contradiction with other methods, e.g., Floquet-Magnus expansion, is explained. The results may be useful for designing effective Hamiltonian models in experiments with ultracold atoms, as well as in the field of ultrafast nonequilibrium magnetism. An example of manipulating exchange interaction in a Mott-Hubbard insulator is considered, where our corrections play an essential role.

  15. STS-112 Flight Day 6 Highlights

    NASA Technical Reports Server (NTRS)

    2002-01-01

    On the sixth flight day of STS-112 (Atlantis crewmembers include Dave Wolf, Mission Specialists; Sandy Magnus, Mission Specialists; Pam Melroy, Pilot; Jeff Ashby, Commander; Piers Sellers, Mission Specialists; Fyodor Yurchikhin, Mission Specialists), Wolf and Sellers are seen preparing for an EVA (extravehicular activity) during which they will service the ISS (International Space Station) to which Atlantis is docked. This will be the 45th EVA in support of ISS assembly and maintenance and the 20th conducted from the ISS. While the astronauts prepare, video footage is shown of the Sahara desert, over which the ISS is passing in a track that will take it over North Africa and the Mediterranean Sea. During the EVA, the External Television Camera Group will be brought out of the station and attached to the station. As the astronauts work, their helmet mounted cameras provide excellent footage of the ISS with the Shuttle docked at the Destiny Laboratory Module. Multiple shots of the station show several modules including Destiny, Quest, Unity and Zarya, as well as Canadarm 2 and Atlantis. The video closes with a wide angle shot of the ISS.

  16. Calculating Floquet states of large quantum systems: A parallelization strategy and its cluster implementation

    NASA Astrophysics Data System (ADS)

    Laptyeva, T. V.; Kozinov, E. A.; Meyerov, I. B.; Ivanchenko, M. V.; Denisov, S. V.; Hänggi, P.

    2016-04-01

    We present a numerical approach to calculate non-equilibrium eigenstates of a periodically time-modulated quantum system. The approach is based on the use of a chain of single-step propagating operators. Each operator is time-specific and constructed by combining the Magnus expansion of the time-dependent system Hamiltonian with the Chebyshev expansion of an operator exponent. The construction of the unitary Floquet operator, which evolves a system state over the full modulation period, is performed by propagating the identity matrix over the period. The independence of the evolution of basis vectors makes the propagation stage suitable for realization on a parallel cluster. Once the propagation stage is completed, a routine diagonalization of the Floquet matrix is performed. Finally, an additional propagation round, now involving the eigenvectors as the initial states, allows to resolve the time-dependence of the Floquet states and calculate their characteristics. We demonstrate the accuracy and scalability of the algorithm by applying it to calculate the Floquet states of two quantum models, namely (i) a synthesized random-matrix Hamiltonian and (ii) a many-body Bose-Hubbard dimer, both of the size up to 104 states.

  17. Gateable Skyrmion Transport via Field-induced Potential Barrier Modulation

    NASA Astrophysics Data System (ADS)

    Fook, Hiu Tung; Gan, Wei Liang; Lew, Wen Siang

    2016-02-01

    We report on the influence of pinning potentials on current-driven skyrmion dynamics and demonstrate that skyrmions can be gated via either magnetic or electric fields. When encountering pinning potentials, skyrmions are well known to simply skirt around them. However, we show that skyrmions can be depinned much more easily when their driving force is oriented against the pinning site rather that the intuitive option of being oriented away. This observation can be exploited together with the normally undesirable Magnus force for the creation of a skyrmion diode. The phenomenon is explained by the increased skyrmion compression resulting from the spin transfer torque opposing the repulsive potential. The smaller skyrmion size then experiences a reduced pinning potential. For practical low-power device applications, we show that the same skyrmion compression can be recreated by applying either a magnetic or electric field. Our analysis provides an insight on the skyrmion dynamics and manipulation that is critical for the realization of skyrmion-based transistors and low-power memory.

  18. STS-112 Mission Highlights Resource, Part 3 of 3

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The STS-112 Mission begins with a view of the center radiator on the S(1) Truss. A good view of the International Space Station's (ISS) Destiny Laboratory, Soyuz Crew Return Vehicle and Quest Airlock are shown from a video camera located at the end of the S(1) Truss Segment. The ISS Canadarm 2 is shown getting in position for spacewalk three. Highlights of flight day eight begin with Pilot Pam Melroy and Mission Specialist Fyodur Yurchikhin shown inside of the Quest Airlock closing the hatch as spacewalkers David Wolf and Piers Sellers move in the outer compartment of the Airlock to begin Extravehicular Activity 3 (EVA 3). During EVA 3, Dave Wolf and Piers Sellers are installing spool positioning devices on ammonia lines located on the ISS. Robot Arm Operators Peggy Whitson and Sandy Magnus are shown reviewing procedures for operating the robot arm. A view of Piers Seller climbing back into the Quest Airlock is presented. During flight day nine, robot arm operators Pam Melroy, Jeff Ashby and Peggy Whitson are in the process of removing spacesuits worn by David Wolf and Piers Sellers. A final farewell of the nine crewmembers shown inside of the Destiny Laboratory is presented during flight day ten. The undocking of Space Shuttle Atlantis from the International Space Station is shown on flight day eleven. This presentation ends on flight day 12 with a view of head up displays and the actual landing of the Space Shuttle Atlantis.

  19. STS-112 Flight Day 3 Highlights

    NASA Technical Reports Server (NTRS)

    2002-01-01

    During the third flight day of STS-112 (Commander Jeff Ashby, Pilot Pam Melroy and Mission Specialists Sandy Magnus, Piers Sellers, David Wolf and Fyodor Yurchikhin), the Space Shuttle Atlantis begins its final approach to the International Space Station (ISS) with which it will dock. The Chinese mainland is seen, at night, at a height of 242 statute miles. In one section of video from a camera onboard the ISS, Atlantis can be seen to be almost directly below the station, at a distance of several hundred feet. The orbiter's docking system is shown, as it is slowly guided by Ashby towards the forward docking port on the ISS's Destiny Laboratory Module and its forward docking port. Above the docking port, the S0 truss structure can be seen, to which the S1 truss structure in Atlantis' payload bay will be attached during this mission. Also seen are the Unity airlock and other modules. Following the completion of docking, in which an excellent shot of the docking system in hard dock is visible, the hatches between the two crafts are opened and the members of Atlantis are greeted by the very excited members of Expedition 5, who have been aboard the ISS for several months.

  20. A general transfer-function approach to noise filtering in open-loop quantum control

    NASA Astrophysics Data System (ADS)

    Viola, Lorenza

    2015-03-01

    Hamiltonian engineering via unitary open-loop quantum control provides a versatile and experimentally validated framework for manipulating a broad class of non-Markovian open quantum systems of interest, with applications ranging from dynamical decoupling and dynamically corrected quantum gates, to noise spectroscopy and quantum simulation. In this context, transfer-function techniques directly motivated by control engineering have proved invaluable for obtaining a transparent picture of the controlled dynamics in the frequency domain and for quantitatively analyzing performance. In this talk, I will show how to identify a computationally tractable set of ``fundamental filter functions,'' out of which arbitrary filter functions may be assembled up to arbitrary high order in principle. Besides avoiding the infinite recursive hierarchy of filter functions that arises in general control scenarios, this fundamental set suffices to characterize the error suppression capabilities of the control protocol in both the time and frequency domain. I will show, in particular, how the resulting notion of ``filtering order'' reveals conceptually distinct, albeit complementary, features of the controlled dynamics as compared to the ``cancellation order,'' traditionally defined in the Magnus sense. Implications for current quantum control experiments will be discussed. Work supported by the U.S. Army Research Office under Contract No. W911NF-14-1-0682.

  1. Higgsless superconductivity from topological defects in compact BF terms

    NASA Astrophysics Data System (ADS)

    Diamantini, M. Cristina; Trugenberger, Carlo A.

    2015-02-01

    We present a new Higgsless model of superconductivity, inspired from anyon superconductivity but P- and T-invariant and generalisable to any dimension. While the original anyon superconductivity mechanism was based on incompressible quantum Hall fluids as average field states, our mechanism involves topological insulators as average field states. In D space dimensions it involves a (D - 1)-form fictitious pseudovector gauge field which originates from the condensation of topological defects in compact low-energy effective BF theories. In the average field approximation, the corresponding uniform emergent charge creates a gap for the (D - 2)-dimensional branes via the Magnus force, the dual of the Lorentz force. One particular combination of intrinsic and emergent charge fluctuations that leaves the total charge distribution invariant constitutes an isolated gapless mode leading to superfluidity. The remaining massive modes organise themselves into a D-dimensional charged, massive vector. There is no massive Higgs scalar as there is no local order parameter. When electromagnetism is switched on, the photon acquires mass by the topological BF mechanism. Although the charge of the gapless mode (2) and the topological order (4) are the same as those of the standard Higgs model, the two models of superconductivity are clearly different since the origins of the gap, reflected in the high-energy sectors are totally different. In 2D this type of superconductivity is explicitly realised as global superconductivity in Josephson junction arrays. In 3D this model predicts a possible phase transition from topological insulators to Higgsless superconductors.

  2. STS-112/Atlantis/ISS 9A Pre-Launch - Launch On-Orbit - Landing - Crew Egress

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The video starts with an introduction of the crew of Space Shuttle Atlantis on STS-112 at their customary pre-flight meal. The crew consists of Commander Jeffrey Ashby, Pilot Pam Melroy, and Mission Specialists David Wolf, Sandra Magnus, Piers Sellers, and Fyodor Yurchikhin. The crew is then shown during suit-up, while exiting the Operations and Checkout Building to board the Astrovan, and during ingress and seating. Launch views include: Beach Tracker, VAB, PAD-B, Tower-1, DLTR-3, Grandstand, Cocoa Beach DOAMS, Playalinda DOAMS, UCS-23, OTV-170, OTV-171, and External Tank Camera. On-orbit footage includes the Atlantis orbiter docking with the ISS (International Space Station). The video shows clips of extravehicluar activities (EVAs), and some of the tasks performed during the mission. Footage included shows the installation of the S1 Truss onto the ISS with the Space Station Remote Manipulator System (Canadarm 2), Canadarm 2 carrying the Ammonia Tank Assembly prior to connection, the checkout of the Thermal Radiator Rotary Joint, the soft docking of an S-Band antenna, and the deployment of the S1 Radiator. An onboard repair of the ISS humidity separator is also shown. Landing views include: VAB, Tower 1, Mid-Field, Runway South End, Runway North End, Tower-2, Cocoa Beach DOAMS, and PPOV. Kennedy Space Center managers greet the crew upon arrival, and Commander Ashby gives a brief speech while standing with his crew members.

  3. Effective Floquet-Gibbs states for dissipative quantum systems

    NASA Astrophysics Data System (ADS)

    Shirai, Tatsuhiko; Thingna, Juzar; Mori, Takashi; Denisov, Sergey; Hänggi, Peter; Miyashita, Seiji

    2016-05-01

    A periodically driven quantum system, when coupled to a heat bath, relaxes to a non-equilibrium asymptotic state. In the general situation, the retrieval of this asymptotic state presents a rather non-trivial task. It was recently shown that in the limit of an infinitesimal coupling, using the so-called rotating wave approximation (RWA), and under strict conditions imposed on the time-dependent system Hamiltonian, the asymptotic state can attain the Gibbs form. A Floquet-Gibbs state is characterized by a density matrix which is diagonal in the Floquet basis of the system Hamiltonian with the diagonal elements obeying a Gibbs distribution, being parametrized by the corresponding Floquet quasi-energies. Addressing the non-adiabatic driving regime, upon using the Magnus expansion, we employ the concept of a corresponding effective Floquet Hamiltonian. In doing so we go beyond the conventionally used RWA and demonstrate that the idea of Floquet-Gibbs states can be extended to the realistic case of a weak, although finite system-bath coupling, herein termed effective Floquet-Gibbs states.

  4. Judging where a ball will go: the case of curved free kicks in football

    NASA Astrophysics Data System (ADS)

    Craig, Cathy M.; Berton, Eric; Rao, Guillaume; Fernandez, Laure; Bootsma, Reinoud J.

    2006-02-01

    This study examined whether adding spin to a ball in the free kick situation in football affects a professional footballer’s perception of the ball’s future arrival position. Using a virtual reality set-up, participants observed the flight paths of aerodynamically realistic free kicks with (±600 rpm) and without sidespin. With the viewpoint being fixed in the centre of the goal, participants had to judge whether the ball would have ended up in the goal or not. Results show that trajectories influenced by the Magnus force caused by sidespin gave rise to a significant shift in the percentage of goal responses. The resulting acceleration that causes the ball to continually change its heading direction as the trajectory unfolds does not seem to be taken into account by the participants when making goal judgments. We conclude that the visual system is not attuned to such accelerated motion, which may explain why goalkeepers appear to misjudge the future arrival point of such curved free kicks.

  5. Significance of Neglected Hydrodynamic Forces on the Motion of Submerged Particles Acted on by External Body Forces

    NASA Astrophysics Data System (ADS)

    Cooper, Daniel; Charonko, John; Vlachos, Pavlos

    2011-11-01

    Recently, the manipulation of submerged particles using electromagnetic body forces has drawn increasing interest from a variety of fields, particularly medicine, where electrophoretic manipulation in lab-on-a-chip applications and magnetic drug targeting have become important areas of interest. As a direct result of this increasing interest a large number of simulations have been performed investigating the performance of devices and systems whose operation is based upon these physics. In the vast majority of cases, these simulations are based upon a force balance of the applicable body force and Stokes drag. Such simulations neglect additional hydrodynamic forces, including the added mass, Basset, Saffman, and Magnus forces. In the current study, the full equations of motion containing all of the aforementioned terms are nondimensionalized leading to a set of nondimensional parameters governing the behavior of the particle. A parametric investigation is then performed by calculating particle trajectories for both Poiseuille and Womersley flows. This analysis reveals that in many cases, the forces neglected in previous simulations are significant and should not be neglected in future studies.

  6. Nonadiabatic semiclassical scattering: Atom-diatom collisions in self-consistent matrix propagator formalism

    NASA Astrophysics Data System (ADS)

    Herman, Michael F.; Freed, Karl F.

    1983-05-01

    The self-consistent matrix propagator method of Laing and Freed is extended to treat semiclassical nonadiabatic scattering in the collinear atom-diatom system. Applications are made to a model system in which diabatic surfaces are parallel, so the nonadiabatic transitions are not well localized in space, thereby introducing difficulties in some previous nonadiabatic semiclassical methods. In the self-consistent matrix propagator method nonadiabatic transitions occur at the boundaries of Magnus regions, and the relative phases, associated with trajectories undergoing transitions at different boundaries, must accurately be determined. This necessitates the determination of the absolute phases of the uniformized classical S matrix, a phase which is unnecessary in single potential surface semiclassical scattering. Semiclassical calculations are compared with full close coupled quantum calculations of Schmalz. The agreement is very good even at relatively low energies. The largest errors enter, as anticipated, for highly classically forbidden transitions whose overall probabilities are, however, rather small. The self-consistent matrix propagator method becomes simpler to apply and more accurate as the total energy increases, i.e., as the fully quantum calculations become prohibitively large. The method has the physical appeal that the self-consistent trajectories follow essentially adiabatic surfaces in strongly interacting regions and diabatic surfaces in weakly interacting regions, with a self-consistent interpolation between these regions.

  7. Study of Solid Particle Behavior in High Temperature Gas Flows

    NASA Astrophysics Data System (ADS)

    Majid, A.; Bauder, U.; Stindl, T.; Fertig, M.; Herdrich, G.; Röser, H.-P.

    2009-01-01

    The Euler-Lagrangian approach is used for the simulation of solid particles in hypersonic entry flows. For flow field simulation, the program SINA (Sequential Iterative Non-equilibrium Algorithm) developed at the Institut für Raumfahrtsysteme is used. The model for the effect of the carrier gas on a particle includes drag force and particle heating only. Other parameters like lift Magnus force or damping torque are not taken into account so far. The reverse effect of the particle phase on the gaseous phase is currently neglected. Parametric analysis is done regarding the impact of variation in the physical input conditions like position, velocity, size and material of the particle. Convective heat fluxes onto the surface of the particle and its radiative cooling are discussed. The variation of particle temperature under different conditions is presented. The influence of various input conditions on the trajectory is explained. A semi empirical model for the particle wall interaction is also discussed and the influence of the wall on the particle trajectory with different particle conditions is presented. The heat fluxes onto the wall due to impingement of particles are also computed and compared with the heat fluxes from the gas.

  8. Aerodynamics of sports balls

    NASA Astrophysics Data System (ADS)

    Mehta, R. D.

    Research data on the aerodynamic behavior of baseballs and cricket and golf balls are summarized. Cricket balls and baseballs are roughly the same size and mass but have different stitch patterns. Both are thrown to follow paths that avoid a batter's swing, paths that can curve if aerodynamic forces on the balls' surfaces are asymmetric. Smoke tracer wind tunnel tests and pressure taps have revealed that the unbalanced side forces are induced by tripping the boundary layer on the seam side and producing turbulence. More particularly, the greater pressures are perpendicular to the seam plane and only appear when the balls travel at velocities high enough so that the roughness length matches the seam heigh. The side forces, once tripped, will increase with spin velocity up to a cut-off point. The enhanced lift coefficient is produced by the Magnus effect. The more complex stitching on a baseball permits greater variations in the flight path curve and, in the case of a knuckleball, the unsteady flow effects. For golf balls, the dimples trip the boundary layer and the high spin rate produces a lift coefficient maximum of 0.5, compared to a baseball's maximum of 0.3. Thus, a golf ball travels far enough for gravitational forces to become important.

  9. A Six Degree of Freedom Trajectory Analysis of Spin-Stabilized Projectiles

    NASA Astrophysics Data System (ADS)

    Gkritzapis, Dimitrios N.; Panagiotopoulos, Elias E.; Margaris, Dionissios P.; Papanikas, Dimitrios G.

    2007-12-01

    A full six degrees of freedom (6-DOF) flight dynamics model is proposed for the accurate prediction of short and long-range trajectories of high and low spin-stabilized projectiles via atmospheric flight to final impact point. The projectile is assumed to be both rigid (non-flexible), and rotationally symmetric about its spin axis launched at low and high pitch angles. The projectile maneuvering motion depends on the most significant force and moment variations in addition to gravity and Magnus Effect. The computational flight analysis takes into consideration the Mach number and total angle of attack effects by means of the variable aerodynamic coefficients. For the purposes of the present work, linear interpolation has been applied from the tabulated database of McCoy's book. The aforementioned variable flight model is compared with a trajectory atmospheric motion based on appropriate constant mean values of the aerodynamic projectile coefficients. Static stability, also called gyroscopic stability, is examined as a necessary condition for stable flight motion in order to locate the initial spinning projectile rotation. Static stability examination takes into account the overturning moment variations with Mach number flight motion. The developed method gives satisfactory results compared with published data of verified experiments and computational codes on atmospheric dynamics model analysis.

  10. Spinal projections from the lower brain stem in the cat as demonstrated by the horseradish peroxidase technique. II. Projections from the dorsolateral pontine tegmentum and raphe nuclei.

    PubMed

    Tohyama, M; Sakai, K; Touret, M; Salvert, D; Jouvet, M

    1979-11-02

    The descending projections to the spinal cord arising from the dorsolateral pontine tegmentum and brain stem raphe nuclei have been investigated by means of the horseradish peroxidase (HRP) technique. Particular attention was taken to clarify the cells of origin and the funicular trajectory of these spinal projections. After injections of HRP into the spinal cord, a significant of HRP labeled neurons were observed in the following dorsolateral pontine tegmental structures: (1) an area ventral to the nucleus cuneiformis; (2) principal locus coeruleus; (3) locus coeruleus a; (4) locuse subcoeruleus; (5) Kölliker-Fuse nucleus; and (6) nucleus parabrachialis lateralis. As a rule, the projections are ipsilateral and descendaphe-spinal projections, we have demonstrated that the nucleus raphe dorsalis also sends axons to the cervical segment of the spinal cord. Furthermore, in accord with previous reports, HRP labeled cells were also identified in the nucleus raphe magnus, pallidus and obscurus, but not in the nucleus raphe centralis superior and pontis. On the whole the present study further clarified the organization of spinal projections from the dorsolateral pons and raphe nuclei and provided some additional anatomical data for the physiology of the tegmentospinal and raphe-spinal projections.

  11. Ballistic reentry vehicles dispersion due to precession stoppage

    NASA Astrophysics Data System (ADS)

    Lin, T. C.; Grabowsky, W. R.; Yelmgren, K. E.; Landa, M.

    1982-08-01

    Ballistic reentry vehicle (RV) precession stoppage phenomena are investigated analytically and several postulated reasons for its occurrence are discussed. Both analytical solutions and six-degree-of-freedom (6DOF) simulations are presented. In addition to the familiar phenomena of roll through zero (RTZ), roll near zero (RNZ) and angle-of-attack divergence, there are four additional aerodynamic forcing functions that are found to be particularly interesting and significant since they can induce the so-called 'space-fixed-trim' phenomena, i.e., the lift-vector becomes momentarily stationary in space. These four forcing functions are: (1) a shift from body-fixed to wind-fixed trim moment in high freestream dynamic pressure environments; (2) RV with transient unstable aerodynamic stability derivative; (3) trim plane migrations induced by a series of asymmetric nose spallations, and (4) a Magnus-type out-of-plane moment in conjunction with the wind-fixed moment induced by ablation lag phenomena. When this occurs, the trajectory deflection becomes prohibitively large. According to the present analytical/numerical results, the initial spin rate can be crucial for the magnitude as well as the direction of the RV dispersion. Finally, some possible physical mechanisms which would cause RV precession stoppage are suggested.

  12. Dreissena polymorpha Pall. postveligers in submersed macrophyte beds of Put-in-Bay, Ohio, as related to rate and density of settlement, macrophyte preference, water depth, and position within beds

    SciTech Connect

    Moore, D.L.

    1995-06-01

    Increased water clarity due in large part to the invasion and spread of Dreissena polymorpha Pall., has allowed reestablishment of nearly continuous beds of submersed macrophytes in Put-in-Bay, Ohio. These beds now serve as sites for settlement by Dreissena veligers. Four transects extending from a maximum depth of 4.0 m to a minimum depth of 0.5 m were established in 1994, to document the time of recruitment, density of postveliger settlement, preferred macrophyte as a substrate, and effects of water depth and location within transects on recruitment. Settlement densities were determined for 100 g wet weight samples of macrophytes harvested along transects by snorkel and scuba. Peak settlement occurred 23 August, 11 days after the second planktonic veliger peak, but continued until early October. Maximum densities were greatest in 1.5-3.5 m water nearer the lakeward end of the transects and decreased in 1.0 m water or shoreward in dense submersed macrophyte beds. A maximum density of 15,150 Dreissena/100 g macrophyte occurred on the perennial Myriophyllum spicatum L., although mean settlement densities were greatest for the perennials M. spicatum, Ceratophyllum demersum L., and the annuals Vallisneria americana Michx. and Najas quadalupensis (Spreng.) Magnus. Macrophyte preference as a settling substrate is most probably a reflection of relative macrophyte abundance and position within dense beds rather than a particular plant architecture. Assessment of densities after autumnal vegetational growth is not yet complete.

  13. STS-112 crew takes a group photo at the 215-foot level

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. - The STS-112 crew gathers for a group photo on the 215-foot level of the Fixed Service Structure. From left are Mission Specialists Fyodor Yurchikhin, Piers Sellers and David Wolf; Pilot Pamela Melroy; Commander Jeffrey Ashby; and Mission Specialist Sandra Magnus. Behind them at left is seen one of the white solid rocket boosters and the orange external tank on Space Shuttle Atlantis. Mission STS-112 is scheduled to launch no earlier than Oct. 2, between 2 and 6 p.m. EDT. STS-112 is the 15th assembly mission to the International Space Station. Atlantis will be carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts. The 11-day mission is expected to conclude with a landing at KSC Oct. 13.

  14. STS-112 crew group photo at launch pad during TCDT

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- During Terminal Countdown Demonstration Test activities, the STS-112 crew poses for a group photo near the launch pad where Space Shuttle Atlantis waits for launch. Standing left to right are Mission Specialist Piers Sellers, Commander Jeffrey Ashby, Mission Specialist David Wolf, Pilot Pamela Melroy, and Mission Specialists Sandra Magnus and Fyodor Yurchikhin, who is with the Russian Space Agency. The TCDT includes emergency egress training and a simulated launch countdown. Mission STS-112 aboard Space Shuttle Atlantis is scheduled to launch no earlier than Oct. 2, between 2 and 6 p.m. EDT. STS-112 is the 15th assembly mission to the International Space Station. Atlantis will be carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts.

  15. Evaluation of fungal and yeast diversity in Slovakian wine-related microbial communities.

    PubMed

    Brežná, Barbara; Zenišová, Katarína; Chovanová, Katarína; Chebeňová, Viera; Kraková, Lucia; Kuchta, Tomáš; Pangallo, Domenico

    2010-11-01

    Since the yeast flora of Slovakian enology has not previously been investigated by culture-independent methods, this approach was applied to two most common cultivars Frankovka (red wine) and Veltlin (white wine), and complemented by cultivation. Model samples included grapes, initial must, middle fermenting must and must in the end-fermentation phase. The cultured isolates were characterized by length polymorphism of rDNA spacer two region using fluorescence PCR and capillary electrophoresis (f-ITS PCR), and some were identified by sequencing. The microbial DNA extracted directly from the samples without cultivation was analysed by f-ITS PCR, amplicons were cloned and sequenced. The use of universal fungal primers led to detection of both yeasts and filamentous fungi. The amplicon of highest intensity and present in all the samples corresponded to Hanseniaspora uvarum. Other species demonstrated by both approaches included Saccharomyces sp., Metschnikowia pulcherrima or M. chrysoperlae, Candida zemplinina, Cladosporium cladosporioides, Botryotinia fuckeliana, Pichia anomala, Candida railenensis, Cryptococcus magnus, Metschnikowia viticola or Candida kofuensis, Pichia kluyveri or Pichia fermentas, Pichia membranifaciens, Aureobasidium pullulans, Alternaria alternata, Erysiphe necator, Rhodotorula glutinis, Issatchenkia terricola and Debaryomyces hansenii. Endemism of Slovakian enological yeasts was suggested on the level of minor genetic variations of the known species and probably not accounting for novel species. The prevalence of H. uvarum over Saccharomyces sp. in the samples was indicated. This is the first culture-independent study of Slovakian enology and the first time f-ITS PCR profiling was used on wine-related microbial communities.

  16. The medieval origins of the concept of hypertension.

    PubMed

    Heydari, Mojtaba; Dalfardi, Behnam; Golzari, Samad E J; Habibi, Hamzeh; Zarshenas, Mohammad Mehdi

    2014-07-01

    Despite the well-known history of hypertension research in the modern era, like many other cardiovascular concepts, main points in the medieval concept of this disease and its early management methods remain obscure. This article attempts to make a brief review on the medieval origin of the concept of this disease from the Hidayat of Al-Akhawayni (?-983 AD). This article has reviewed the chapter of "Fi al-Imtela" (About the Fullness) from the Hidβyat al-Muta'allimin fi al-Tibb (The Students' Handbook of Medicine) of Al-Akhawayni. The definition, symptoms and treatments presented for the Imtela are compared with the current knowledge on hypertension. Akhawayni believed that Imtela could result from the excessive amount of blood within the blood vessels. It can manifest with symptoms including the presence of a pulsus magnus, sleepiness, weakness, dyspnea, facial blushing, engorgement of the vessels, thick urine, vascular rupture, and hemorrhagic stroke. He also suggested some ways to manage al-Imtela'. These include recommendations of changes in lifestyle (staying away from anger and sexual intercourse) and dietary program for patients (avoiding the consumption of wine, meat, and pastries, reducing the volume of food in a meal, maintaining a low-energy diet and the dietary usage of spinach and vinegar). Al-Akhawayni's description of "Imtela," despite of its numerous differences with current knowledge of hypertension, can be considered as medieval origin of the concept of hypertension.

  17. The backward jump of a box moss mite

    PubMed Central

    Wauthy, G.; Leponce, M.; Bana, N.; Sylin, G.; Lions, J.-C.

    1998-01-01

    Indotritia cf. heterotrichia, a box moss mite 800 μm in length, combines the abilities to curl up and to jump. Despite the lack of specialized legs and of extensor muscles in its knee joints, the backward leap is characterized by a short take-off time (ca. 0.5 ms). This is apparently facilitated by a catch mechanism made up of a small hook on each forefemur that hitches on the rim of the anterior shield of the body and maintains the forelegs in a flexed position during a prejump phase. While the animal is propelled backwards, its body simultaneously spins in a forward direction: it is supposed that, at take-off, the hindlegs initiate a forward rolling of the body, which is powered by internal hydraulic pressure, before the hook disengages from the shield rim and triggers a sudden backward impulse. The non-parabolic trajectory of the flight can be described with a model where the air resistance due to the spin (Magnus effect) and to the translatory motion is taken into account.

  18. 5-HT2A receptor antagonist M100907 reduces serotonin synthesis: An autoradiographic study

    PubMed Central

    Hasegawa, Shu; Fikre-Merid, Maraki; Diksic, Mirko

    2013-01-01

    The effects of the administration of the serotonin (5-HT)2A antagonist, M100907, on 5-HT synthesis rates, were evaluated using the α-[14C]methyl-L-tryptophan (α-MTrp) autoradiographic method. In the treatment study, M100907 (10 mg/kg) was injected intraperitoneally 30 min before the α-MTrp injection (30 μCi over 2 min). A single dose of M100907 caused a significant decrease in the synthesis in the anterior olfactory nucleus, accumbens nucleus, frontal cortex, sensory-motor cortex, cingulate cortex, medial caudate-putamen, dorsal thalamus, substantia nigra, inferior collicus, raphe magnus nucleus, superior olive, and raphe pallidus nucleus. These data suggest that the terminal 5-HT2A receptors are involved in the regulation of 5-HT synthesis in the entire brain. Further, 5-HT synthesis is likely regulated by the 5-HT2A antagonistic property of M100907 in the cortices, anterior olfactory nucleus, caudate putamen, and nucleus accumbens. PMID:22056993

  19. Complete Genome Sequence of Finegoldia magna, an Anaerobic Opportunistic Pathogen

    PubMed Central

    Goto, Takatsugu; Yamashita, Atsushi; Hirakawa, Hideki; Matsutani, Minenosuke; Todo, Kozo; Ohshima, Kenshiro; Toh, Hidehiro; Miyamoto, Kazuaki; Kuhara, Satoru; Hattori, Masahira; Shimizu, Tohru; Akimoto, Shigeru

    2008-01-01

    Finegoldia magna (formerly Peptostreptococcus magnus), a member of the Gram-positive anaerobic cocci (GPAC), is a commensal bacterium colonizing human skin and mucous membranes. Moreover, it is also recognized as an opportunistic pathogen responsible for various infectious diseases. Here, we report the complete genome sequence of F. magna ATCC 29328. The genome consists of a 1 797 577 bp circular chromosome and an 189 163 bp plasmid (pPEP1). The metabolic maps constructed based on the genome information confirmed that most F. magna strains cannot ferment most sugars, except fructose, and have various aminopeptidase activities. Three homologs of albumin-binding protein, a known virulence factor useful for antiphagocytosis, are encoded on the chromosome, and one albumin-binding protein homolog is encoded on the plasmid. A unique feature of the genome is that F. magna encodes many sortase genes, of which substrates may be involved in bacterial pathogenesis, such as antiphagocytosis and adherence to the host cell. The plasmid pPEP1 encodes seven sortase and seven substrate genes, whereas the chromosome encodes four sortase and 19 substrate genes. These plasmid-encoded sortases may play important roles in the pathogenesis of F. magna by enriching the variety of cell wall anchored surface proteins. PMID:18263572

  20. The personal is scientific: Women, gender, and the production of sexological knowledge in Germany and Austria, 1900-1931.

    PubMed

    Leng, Kirsten

    2015-08-01

    This article addresses the roles women and gender played in the production of sexological knowledge in the early 20th century, particularly in German-speaking Europe. Although existing scholarship focuses almost exclusively on the work of "founding fathers" such as Richard von Krafft-Ebing and Magnus Hirschfeld, women in fact made important contributions to the field. Based on analysis of texts written between 1900 and 1931, this article shows how women were able to successfully mobilize their gender as a privileged form of "situated knowledge," and thereby assert their authority over and superior insights into certain subject areas, namely, female sexualities and sexual difference. At the same time, however, this article also highlights the constraints upon women's gendered standpoint. It shows that women's sexological writing was not just informed by their gender but also by their class and race. Moreover, because gender threatened to cast their work as insufficiently objective and scientific, women cleaved to sexology's rules of evidence and argumentation, and adopted the field's ideological trappings in order to participate in discursive contestations over sexual truths. By interrogating gender, this article introduces much-needed nuance into existing understandings of sexology, and reframes sexology itself as a site wherein new sexual subjectivities were imagined, articulated, and debated. However, it also raises fundamental questions about women sexologists' capacity to create knowledge about women and female sexualities that was truer, more correct, and more authentic than that produced by men.

  1. Wave–vortex interactions in the nonlinear Schrödinger equation

    SciTech Connect

    Guo, Yuan Bühler, Oliver

    2014-02-15

    This is a theoretical study of wave–vortex interaction effects in the two-dimensional nonlinear Schrödinger equation, which is a useful conceptual model for the limiting dynamics of superfluid quantum condensates at zero temperature. The particular wave–vortex interaction effects are associated with the scattering and refraction of small-scale linear waves by the straining flows induced by quantized point vortices and, crucially, with the concomitant nonlinear back-reaction, the remote recoil, that these scattered waves exert on the vortices. Our detailed model is a narrow, slowly varying wavetrain of small-amplitude waves refracted by one or two vortices. Weak interactions are studied using a suitable perturbation method in which the nonlinear recoil force on the vortex then arises at second order in wave amplitude, and is computed in terms of a Magnus-type force expression for both finite and infinite wavetrains. In the case of an infinite wavetrain, an explicit asymptotic formula for the scattering angle is also derived and cross-checked against numerical ray tracing. Finally, under suitable conditions a wavetrain can be so strongly refracted that it collapses all the way onto a zero-size point vortex. This is a strong wave–vortex interaction by definition. The conditions for such a collapse are derived and the validity of ray tracing theory during the singular collapse is investigated.

  2. Coastal villas, maritime villas; a perspective from Southern Britain

    NASA Astrophysics Data System (ADS)

    Tomalin, David

    2006-01-01

    The coastal siting of Romano-British villas is generally discussed and attention is particularly focused on the Channel seaboard of Britain. Here, comparison is made with the distribution of those natural harbours and offshore anchorages that have been traditionally favoured by sailing craft. These are clearly described in the first edition of Hobb’s British Channel Pilot of 1859. A relationship is proposed between the rare incidence of leeward anchorages and the siting of villas at Folkestone, Eastbourne, Sidlesham, Weymouth and Honeyditches. Other villas with significant maritime settings are identified at Southwick, Fishbourne, Emsworth, and Brading all of which adjoin harbours or ‘roads’ identified by Hobbs. In the Eastern Solent, anchorages at Spithead, Mother Bank and Cowes Roads are equated with the Magnus Portus described by Ptolemy. At this location some supportive evidence is offered by Roman ceramics recently recovered from the seabed. Attention is also drawn to maritime themes in the mosaics at Fishbourne, Brading and Low Ham where the chosen mythological scenes appear to be an overt expression of contemporary nautical preoccupations.

  3. STS-112 crew practices emergency egress training during TCDT

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- During emergency egress training from the launch pad, the STS-112 crew get instructions on using the slidewire basket. From left, Mission Specialist Piers Sellers (back to camera), Pilot Pamela Melroy, Mission Specialists Sandra Magnus and Fyodor Yurchikhin (with the Russian Space Agency), watch as Commander Jeffrey Ashby (below right) grabs the release lever. Not seen is Mission Specialist David Wolf. The training is part of Terminal Countdown Demonstration Test activities, which include a simulated launch countdown. Mission STS-112 aboard Space Shuttle Atlantis is scheduled to launch no earlier than Oct. 2, between 2 and 6 p.m. EDT. STS-112 is the 15th assembly mission to the International Space Station. Atlantis will be carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts.

  4. Multiple muscular variations including tenuissimus and tensor fasciae suralis muscles in the posterior thigh of a human case.

    PubMed

    Arakawa, Takamitsu; Kondo, Takahiro; Tsutsumi, Masahiro; Watanabe, Yuko; Terashima, Toshio; Miki, Akinori

    2017-03-07

    The posterior thigh muscles on the right side of an 81-year-old male cadaver had multiple variations, denoted muscles I-IV. Muscle I originated from the posteromedial surface of the greater trochanter and divided into two muscle bellies. These muscle bellies fused with the long head of the biceps femoris and were innervated by two branches from muscular branches of the semitendinosus and the long head of the biceps. Muscle II separated from the medial surface of the long head of the biceps in the proximal third and fused with the semitendinosus in the distal fourth. Muscle III was a biventer muscle. Its superior belly separated from the medial surface of the long head of the biceps in the distal third. The inferior belly of this muscle fused with the posterior surface of the crural fascia and was innervated by the tibial nerve. Muscle IV separated from the adductor magnus muscle, passed between the long and short heads of the biceps, fused with the inferior belly of muscle III, and was innervated by the muscular branch of the common fibular nerve to the short head of the biceps. Peeling off the epineurium of the muscular branches to the inferior belly of muscle III showed that this nerve fascicle divided from the common trunk with branches to the gastrocnemius and soleus muscles. The inferior bellies of muscle III and muscle IV were thought to be equivalent to the tensor fasciae suralis and tenuissimus muscles, respectively.

  5. A taxonomic revision of the genus Oxyopomyrmex André, 1881 (Hymenoptera: Formicidae).

    PubMed

    Salata, Sebastian; Borowiec, Lech

    2015-09-30

    Oxyopomyrmex André, 1881 is a small genus of myrmicine ants found in arid grasslands of the Mediterranean region. Here we provide a new taxonomic revision of the genus. Twelve species are recognized, including five new to science: O. laevibus sp. nov. (Greece: Crete), O. magnus sp. nov. (Spain), O. negevensis sp. nov. (Israel) O. polybotesi sp. nov. (Greece: Nisyros, W Turkey) and O. pygmalioni sp. nov. (Cyprus). Oxyopomyrmex santschii var. nigripes Santschi, 1907 and O. santschii var. nitidior Santschi, 1910 are raised to species level. The following new synonymies are proposed: O. krueperi Forel, 1911 = O. lagoi Menozzi, 1936 syn. nov.; O. nigripes Santschi, 1907 = O. sabulonis var. rugocciput Santschi, 1923 syn. nov. = O. emeryi var. brunnescens Santschi, 1929 syn. nov.; O. nitidior Santschi, 1910 = O. emeryi var. laticeps Santschi, 1915 syn. nov. = O. emeryi st. sabulonis Santschi, 1915 syn. nov.; O. saulcyi Emery, 1889 = O. santschii Forel, 1904 syn. nov. = O. santschii var. siciliana Karavaiev, 1912 syn. nov. = O. gaetulus Santschi, 1929 syn. nov. = O. saulcyi var. latinodis Santschi, 1939 syn. nov. A neotype for O. oculatus André, 1881 is designated. An identification key based on the gyne, male and worker caste is provided.

  6. Emerging trends in the diagnosis of human African Trypanosomiasis.

    PubMed

    Radwanska, Magdalena

    2010-12-01

    Human African trypanosomiasis (HAT) or sleeping sickness is caused by protozoan parasites Trypanosoma brucei gambiense and T. b. rhodesiense. Despite the enormous technological progress in molecular parasitology in recent years, the diagnosis of HAT is still problematic due to the lack of specific tools. To date, there are two realities when it comes to HAT; the first one being the world of modern experimental laboratories, equipped with the latest state-of-the-art technology, and the second being the world of HAT diagnosis, where the latest semi-commercial test was introduced 30 years ago (Magnus et al. 1978). Hence, it appears that the lack of progress in HAT diagnosis is not primarily due to a lack of scientific interest or a lack of research funds, but mainly results from the many obstacles encountered in the translation of basic research into field-applicable diagnostics. This review will provide an overview of current diagnostic methods and highlight specific difficulties in solving the shortcomings of these methods. Future perspectives for accurate, robust, affordable diagnostics will be discussed as well.

  7. Host-Pathogen Interactions: II. Parameters Affecting Polysaccharide-degrading Enzyme Secretion by Colletotrichum lindemuthianum Grown in Culture.

    PubMed

    English, P D; Jurale, J B; Albersheim, P

    1971-01-01

    The effect of a number of physiological variables on the secretion of polysaccharide-degrading enzymes by culture-grown Colletotrichum lindemuthianum (Saccardo and Magnus) Scribner was determined. The number of spores used to inoculate cultures grown on isolated bean hypocotyl cell walls affects the time after inoculation at which enzyme secretion occurs, but has no significant effect on the maximal amount of enzyme ultimately secreted. Cell walls isolated from bean leaves, first internodes, or hypocotyls (susceptible to C. lindemuthianum infection), when used as carbon source for C. lindemuthianum growth, stimulate the fungus to secrete more alpha-galactosidase than do cell walls isolated from roots (resistant to infection). The concentration of carbon source used for fungal growth determines the final level of enzyme activity in the culture fluid. The level of enzyme secretion is not proportional to fungal growth; rather, enzyme secretion is induced. Maximal alpha-galactosidase activity in the culture medium is found when the concentration of cell walls used as carbon source is 1% or greater. A higher concentration of cell walls is necessary for maximal alpha-arabinosidase activity. Galactose, when used as the carbon source, stimulates alpha-galactosidase secretion but, at comparable concentrations, is less effective in doing so than are cell walls. Polysaccharide-degrading enzymes are secreted by C. lindemuthianum at different times during growth of the pathogen on isolated cell walls. Pectinase and alpha-arabinosidase are secreted first, followed by beta-xylosidase and cellulase, then beta-glucosidase, and, finally, alpha-galactosidase.

  8. STS-112 crew arrives at KSC's SLF for launch

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. -- STS-112 crew members share a few words after their arrival at the KSC Shuttle Landing Facility to begin launch preparations. In the center are Commander Jeffrey Ashby (left) and Mission Specialist David Wolf (right). With their backs to the camera are Mission Specialists Piers Sellers (far left) and Sandra Magnus (far right). Not shown are Pilot Pamela Melroy and Mission Specialist Fyodor Yurchikhin, who is with the Russian Space Agency. STS-112, aboard Space Shuttle Atlantis, is the 15th assembly mission to the International Space Station. Atlantis will be carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts. The 11-day mission includes three spacewalks. Launch is scheduled for Oct. 2 between 2 and 6 p.m.

  9. Muscle activity during stance phase of walking: comparison of males with transfemoral amputation with osseointegrated fixations to nondisabled male volunteers.

    PubMed

    Pantall, Annette; Ewins, David

    2013-01-01

    A recent development in prosthetics is the osseointegrated fixation (OF), with improvements in comfort, fatigue, hip movement, and ease of prosthetic attachment reported. However, little information is available regarding muscle function. This study reports on selected gait parameters of the residual limb during the stance phase of level overground walking, focusing on muscle activity. Five males with transfemoral amputation (TFA) with OFs were recruited. Ground reaction force (GRF), lower-limb kinematics, and surface electromyography (sEMG) from residual-limb muscles were recorded. sEMG data were also collected from a group of 10 nondisabled male subjects. Interstance variability of gait parameters was assessed by coefficient of multiple correlations. Repeatability of GRF and hip kinematics was high, whereas repeatability of the sEMG was low for four of the five individuals with TFA. Interstance variability of the sEMG for gluteus medius (GMED) was significantly greater in the group with TFA. The main difference in sEMG between the groups was the phase, with GMED and adductor magnus displaying greater differences than their counterparts in the nondisabled group. Results demonstrate that muscles in the residual limb retain aspects of their previous functional pattern.

  10. Two-loop master integrals for the mixed EW-QCD virtual corrections to Drell-Yan scattering

    NASA Astrophysics Data System (ADS)

    Bonciani, Roberto; Di Vita, Stefano; Mastrolia, Pierpaolo; Schubert, Ulrich

    2016-09-01

    We present the calculation of the master integrals needed for the two-loop QCD × EW corrections to q+overline{q}to {l}-+{l}+ and q+overline{q}^'to {l}-+overline{ν} , for massless external particles. We treat the W and Z bosons as degenerate in mass. We identify three types of diagrams, according to the presence of massive internal lines: the no-mass type, the one-mass type, and the two-mass type, where all massive propagators, when occurring, contain the same mass value. We find a basis of 49 master integrals and evaluate them with the method of the differential equations. The Magnus exponential is employed to choose a set of master integrals that obeys a canonical system of differential equations. Boundary conditions are found either by matching the solutions onto simpler integrals in special kinematic configurations, or by requiring the regularity of the solution at pseudothresholds. The canonical master integrals are finally given as Taylor series around d = 4 space-time dimensions, up to order four, with coefficients given in terms of iterated integrals, respectively up to weight four.

  11. Boson-mediated quantum spin simulators in transverse fields: X Y model and spin-boson entanglement

    NASA Astrophysics Data System (ADS)

    Wall, Michael L.; Safavi-Naini, Arghavan; Rey, Ana Maria

    2017-01-01

    The coupling of spins to long-wavelength bosonic modes is a prominent means to engineer long-range spin-spin interactions, and has been realized in a variety of platforms, such as atoms in optical cavities and trapped ions. To date, much of the experimental focus has been on the realization of long-range Ising models, but generalizations to other spin models are highly desirable. In this work, we explore a previously unappreciated connection between the realization of an X Y model by off-resonant driving of a single sideband of boson excitation (i.e., a single-beam Mølmer-Sørensen scheme) and a boson-mediated Ising simulator in the presence of a transverse field. In particular, we show that these two schemes have the same effective Hamiltonian in suitably defined rotating frames, and analyze the emergent effective X Y spin model through a truncated Magnus series and numerical simulations. In addition to X Y spin-spin interactions that can be nonperturbatively renormalized from the naive Ising spin-spin coupling constants, we find an effective transverse field that is dependent on the thermal energy of the bosons, as well as other spin-boson couplings that cause spin-boson entanglement not to vanish at any time. In the case of a boson-mediated Ising simulator with transverse field, we discuss the crossover from transverse field Ising-like to X Y -like spin behavior as a function of field strength.

  12. Peeled mammalian skeletal muscle fibers. Possible stimulation of Ca2+ release via a transverse tubule-sarcoplasmic reticulum mechanism

    PubMed Central

    1985-01-01

    Single muscle fibers from rabbit soleus and adductor magnus and from semitendinosus muscles were peeled to remove the sarcolemma and then stimulated to release Ca2+ by (a) caffeine application or (b) ionic depolarization accomplished via substitution of choline chloride for potassium propionate at constant [K+] X [Cl-] in the bathing solution. Each stimulus, ionic or caffeine, elicited an isometric tension transient that appeared to be due to Ca2+ released from the sarcoplasmic reticulum (SR). The peak magnitude of the ionic (Cl- - induced) tension transient increased with increasing Cl- concentration. The application of ouabain to fibers after peeling had no effect on either type of tension transient. However, soaking the fibers in a ouabain solution before peeling blocked the Cl- -induced but not the caffeine-induced tension transient, which suggests that ouabain's site of action is extracellular, perhaps inside transverse tubules (TTs). Treating the peeled fibers with saponin, which should disrupt TTs to a greater extent than SR membrane, greatly reduced or eliminated the Cl- - induced tension transient without significantly altering the caffeine- induced tension transient. These results suggest that the Cl- -induced tension transient is elicited via stimulation of sealed, polarized TTs rather than via ionic depolarization of the SR. PMID:4056734

  13. Progressive supranuclear palsy: neuronal and glial cytoskeletal pathology in the higher order processing autonomic nuclei of the lower brainstem.

    PubMed

    Rüb, U; Del Tredici, K; Schultz, C; de Vos, R A I; Jansen Steur, E N H; Arai, K; Braak, H

    2002-02-01

    The medial and lateral parabrachial nuclei (MPB, LPB), the gigantocellular reticular nucleus (GI), the raphes magnus (RMG) and raphes obscurus nuclei (ROB), as well as the intermediate reticular zone (IRZ) represent pivotal subordinate brainstem centres, all of which control autonomic functions. In this study, we investigated the occurrence and severity of the neuronal and glial cytoskeletal pathology in these six brainstem nuclei from 17 individuals with clinically diagnosed and neuropathologically confirmed progressive supranuclear palsy (PSP). The association between the severity of the pathology and the duration of the disease was investigated by means of correlation analysis. The brainstem nuclei in all of the PSP cases were affected by the neuronal cytoskeletal pathology, with the IRZ and GI regularly showing severe involvement, the MPB, RMG, and ROB marked involvement, and the LPB mild involvement. In the six nuclear greys studied, glial cells undergo alterations of their cytoskeleton on an irregular basis, whereby diseased oligodendrocytes predominantly presented as coiled bodies and affected astrocytes as thorn-shaped astrocytes. In all six nuclei, the severity of the neuronal or glial cytoskeletal pathology showed no correlation with the duration of PSP. In view of their functional role, the neuronal pathology in the nuclei studied offers a possible explanation for the autonomic dysfunctions that eventually develop in the course of PSP.

  14. Gateable Skyrmion Transport via Field-induced Potential Barrier Modulation

    PubMed Central

    Fook, Hiu Tung; Gan, Wei Liang; Lew, Wen Siang

    2016-01-01

    We report on the influence of pinning potentials on current-driven skyrmion dynamics and demonstrate that skyrmions can be gated via either magnetic or electric fields. When encountering pinning potentials, skyrmions are well known to simply skirt around them. However, we show that skyrmions can be depinned much more easily when their driving force is oriented against the pinning site rather that the intuitive option of being oriented away. This observation can be exploited together with the normally undesirable Magnus force for the creation of a skyrmion diode. The phenomenon is explained by the increased skyrmion compression resulting from the spin transfer torque opposing the repulsive potential. The smaller skyrmion size then experiences a reduced pinning potential. For practical low-power device applications, we show that the same skyrmion compression can be recreated by applying either a magnetic or electric field. Our analysis provides an insight on the skyrmion dynamics and manipulation that is critical for the realization of skyrmion-based transistors and low-power memory. PMID:26883575

  15. The Evolutionary Implications of Hemipenial Morphology of Rattlesnake Crotalus durissus terrificus (Laurent, 1768) (Serpentes: Viperidae: Crotalinae)

    PubMed Central

    Porto, Marcovan; de Oliveira, Marco Antonio; Pissinatti, Lorenzo; Rodrigues, Renata Lopes; Rojas-Moscoso, Julio Alejandro; Cogo, José Carlos; Metze, Konradin; Antunes, Edson; Nahoum, César; Mónica, Fabíola Z.; De Nucci, Gilberto

    2013-01-01

    Most amniotes vertebrates have an intromittent organ to deliver semen. The reptile Sphenodon and most birds lost the ancestral penis and developed a cloaca-cloaca mating. Known as hemipenises, the copulatory organ of Squamata shows unique features between the amniotes intromittent organ. They are the only paired intromittent organs across amniotes and are fully inverted and encapsulated in the tail when not in use. The histology and ultrastructure of the hemipenes of Crotalus durissus rattlesnake is described as the evolutionary implications of the main features discussed. The organization of hemipenis of Crotalus durissus terrificus in two concentric corpora cavernosa is similar to other Squamata but differ markedly from the organization of the penis found in crocodilians, testudinata, birds and mammals. Based on the available data, the penis of the ancestral amniotes was made of connective tissue and the incorporation of smooth muscle in the framework of the sinusoids occurred independently in mammals and Crotalus durissus. The propulsor action of the muscle retractor penis basalis was confirmed and therefore the named should be changed to musculus hemipenis propulsor.The retractor penis magnus found in Squamata has no homology to the retractor penis of mammals, although both are responsible for the retraction of the copulatory organ. PMID:23840551

  16. Occultifur kilbournensis f.a. sp. nov., a new member of the Cystobasidiales associated with maize (Zea mays) cultivation.

    PubMed

    Kurtzman, Cletus P; Robnett, Christie J

    2015-05-01

    During a study of microorganisms associated with maize (Zea mays) cultivation, yeasts were isolated from overwintered stalks, cobs and surrounding soil, which were collected from an agricultural field in south-central Illinois, USA. Predominant among isolates were two species of Cryptococcus (Cr. flavescens, Cr. magnus) and a red yeast that D1/D2 LSU rRNA gene sequences revealed to be a new species of the basidiomycete yeast genus Occultifur. The species, which was not detected in the same field during the growing season, is described here as Occultifur kilbournensis (MycoBank number MB 811259; type strain NRRL Y-63695, CBS 13982, GenBank numbers, D1/D2 LSU rRNA gene, KP413160, ITS, KP413162; allotype strain NRRL Y-63699, CBS 13983). Mixture of the type and allotype strains resulted in formation of hyphae with clamp connections and a small number of apparent basidia following incubation on 5% malt extract agar at 15 °C for 2 months. In view of the uncertainty of the life cycle, the new species is being designated as forma asexualis. From analysis of D1/D2 and ITS nucleotide sequences, the new species is most closely related to Occultifur externus.

  17. Berry curvature and dynamics of a magnetic bubble

    NASA Astrophysics Data System (ADS)

    Koshibae, Wataru; Nagaosa, Naoto

    2016-04-01

    Magnetic bubbles have been the subject of intensive studies aiming to investigate their applications to memory devices. A bubble can be regarded as the closed domain wall and is characterized by the winding number of the in-plane components or the skyrmion number N sk , which are related to the number of Bloch lines (BLs). For the magnetic bubbles without BLs, the Thiele equation assuming no internal distortion describes the center-of-mass motion of the bubbles very well. For the magnetic bubbles with BLs, on the other hand, their dynamics is affected seriously by that of BLs along the domain wall. Here we show theoretically, that the distribution of the Berry curvature b z , i.e., the solid angle formed by the magnetization vectors, in the bubble plays the key role in the dynamics of a bubble with {N}{sk}=0 in a dipolar magnet. In this case, the integral of b z over the space is zero, while the nonuniform distribution of b z and associated Magnus force induce several nontrivial coupled dynamics of the internal deformation and center-of-mass motion as explicitly demonstrated by numerical simulations of Landau-Lifshitz-Gilbert equation. These findings give an alternative view and will pave a new route to design the bubble dynamics.

  18. STS-112 Crew Portrait

    NASA Technical Reports Server (NTRS)

    2002-01-01

    These 5 astronauts and cosmonaut, all members of the STS-112 mission, pose for a crew portrait. Pictured from left to right are: Astronauts Sandra H. Magnus, mission specialist; David A. Wolf, mission specialist; Pamela A. Melroy, pilot; Jeffrey S. Ashby, commander; Piers J. Sellers, mission specialist; and cosmonaut Fyodor Yurchikhin, mission specialist representing Rosaviakosmos. STS-112 launched aboard the Space Shuttle Atlantis October 7, 2002 for an 11-day mission completing three sessions of Extra Vehicular Activity(EVA). Its primary mission was to install the Starboard (S1) Integrated Truss Structure and Equipment Translation Aid (CETA) Cart to the ISS. The S1 truss provides structural support for the orbiting research facility's radiator panels, which use ammonia to cool the Station's complex power system. The S1 truss, attached to the S0 (S Zero) truss installed by the previous STS-110 mission, flows 637 pounds of anhydrous ammonia through three heat rejection radiators. The truss is 45-feet long, 15-feet wide, 10-feet tall, and weighs approximately 32,000 pounds. The CETA is the first of two human-powered carts that will ride along the railway on the ISS providing a mobile work platform for future extravehicular activities by astronauts.

  19. Applied anatomy of the fasciocutaneous branch of the third perforator artery of the deep femoral artery

    PubMed Central

    de Araujo Netto, Belmino Corrêa; Ferreira, Lydia Masako; de Oliveira Santos, Ivan Dunshee Abranches

    2003-01-01

    A study of the anatomy of the fasciocutaneous branch of the third perforator artery of the deep femoral artery was performed to help the elaboration of a fasciocutaneous flap for the reconstruction of skin and subcutaneous and deep fascia of the knee and popliteal region. Forty thighs in 27 fresh cadavers were dissected. In all of the thighs, the third perforator artery was found to arise from the deep femoral artery and reach the posterior aspect of the thigh after perforating the adductor magnus muscle. At that point it was also found that the third perforator artery gives off a branch that emerges through the intermuscular septum between the vast lateral muscle and the long head of the biceps femoral muscle, then crosses the posterior cutaneous nerve and moves directly on to perforate the deep fascia and then to bifurcate into two other branches: one ascending and one descending. The cutaneous area of the flap of the thigh’s posterior region, nourished by the fasciocutaneous branch, was evaluated through the injection of dye. Dying of the upper medial, middle medial, lower medial and lower lateral areas of the flap was not successful in all of the dissected thighs. Nevertheless, the upper lateral and the middle lateral areas were dyed successfully in all 40 dissected thighs of the 27 cadavers. PMID:24115846

  20. Analysis of ITS1 and ITS2 sequences in Ensis razor shells: suitability as molecular markers at the population and species levels, and evolution of these ribosomal DNA spacers.

    PubMed

    Vierna, Joaquín; Martínez-Lage, Andrés; González-Tizón, Ana M

    2010-01-01

    Internal transcribed spacer 1 and 2 (ITS1 and ITS2) sequences were analysed in Ensis razor shells (Mollusca: Bivalvia: Pharidae). We aimed to (1) test ITS1 and ITS2 as molecular markers at the population level in the successful alien E. directus (Conrad, 1843); (2) test these spacers at the species level in E. directus and three other Ensis species, E. siliqua (L., 1758), E. macha (Molina, 1782), and E. magnus (Schumacher, 1817); and (3) analyse the evolutionary processes that may be shaping Ensis ITS1 and ITS2 extant variation. In E. directus, despite the intragenomic divergence detected, ITS1 and ITS2 were informative in differentiating the geographic areas considered (Denmark and Canada) by means of both the insertion-deletion polymorphism and the nucleotide polymorphism. In this species, the 5.8S ribosomal gene (5.8S) showed scarce polymorphism. At the species level, maximum parsimony and maximum likelihood analyses revealed that ITS1 and ITS2 may be suitable to reconstruct Ensis phylogenetic relationships. Finally, the evolutionary models that best fit the long-term evolution of Ensis ITS1-5.8S-ITS2 are discussed. A mixed process of concerted evolution, birth-and-death evolution, and selection is chosen as an option that may reconcile the long-term evolution of Ensis ITS1-5.8S-ITS2 and 5S ribosomal DNA.

  1. Effective Hamiltonians for Rapidly Driven Many-Body Lattice Systems: Induced Exchange Interactions and Density-Dependent Hoppings.

    PubMed

    Itin, A P; Katsnelson, M I

    2015-08-14

    We consider 1D lattices described by Hubbard or Bose-Hubbard models, in the presence of periodic high-frequency perturbations, such as uniform ac force or modulation of hopping coefficients. Effective Hamiltonians for interacting particles are derived using an averaging method resembling classical canonical perturbation theory. As is known, a high-frequency force may renormalize hopping coefficients, causing interesting phenomena such as coherent destruction of tunneling and creation of artificial gauge fields. We find explicitly additional corrections to the effective Hamiltonians due to interactions, corresponding to nontrivial processes such as single-particle density-dependent tunneling, correlated pair hoppings, nearest neighbor interactions, etc. Some of these processes arise also in multiband lattice models, and are capable of giving rise to a rich variety of quantum phases. The apparent contradiction with other methods, e.g., Floquet-Magnus expansion, is explained. The results may be useful for designing effective Hamiltonian models in experiments with ultracold atoms, as well as in the field of ultrafast nonequilibrium magnetism. An example of manipulating exchange interaction in a Mott-Hubbard insulator is considered, where our corrections play an essential role.

  2. The Evolutionary Implications of Hemipenial Morphology of Rattlesnake Crotalus durissus terrificus (Laurent, 1768) (Serpentes: Viperidae: Crotalinae).

    PubMed

    Porto, Marcovan; de Oliveira, Marco Antonio; Pissinatti, Lorenzo; Rodrigues, Renata Lopes; Rojas-Moscoso, Julio Alejandro; Cogo, José Carlos; Metze, Konradin; Antunes, Edson; Nahoum, César; Mónica, Fabíola Z; De Nucci, Gilberto

    2013-01-01

    Most amniotes vertebrates have an intromittent organ to deliver semen. The reptile Sphenodon and most birds lost the ancestral penis and developed a cloaca-cloaca mating. Known as hemipenises, the copulatory organ of Squamata shows unique features between the amniotes intromittent organ. They are the only paired intromittent organs across amniotes and are fully inverted and encapsulated in the tail when not in use. The histology and ultrastructure of the hemipenes of Crotalus durissus rattlesnake is described as the evolutionary implications of the main features discussed. The organization of hemipenis of Crotalus durissus terrificus in two concentric corpora cavernosa is similar to other Squamata but differ markedly from the organization of the penis found in crocodilians, testudinata, birds and mammals. Based on the available data, the penis of the ancestral amniotes was made of connective tissue and the incorporation of smooth muscle in the framework of the sinusoids occurred independently in mammals and Crotalus durissus. The propulsor action of the muscle retractor penis basalis was confirmed and therefore the named should be changed to musculus hemipenis propulsor.The retractor penis magnus found in Squamata has no homology to the retractor penis of mammals, although both are responsible for the retraction of the copulatory organ.

  3. Cytogenetic characterisation of the razor shells Ensis directus (Conrad, 1843) and E. minor (Chenu, 1843) (Mollusca: Bivalvia)

    NASA Astrophysics Data System (ADS)

    González-Tizón, Ana M.; Rojo, Verónica; Vierna, Joaquín; Jensen, K. Thomas; Egea, Emilie; Martínez-Lage, Andrés

    2013-03-01

    The European razor shell Ensis minor (Chenu 1843) and the American E. directus (Conrad 1843) have a diploid chromosome number of 38 and remarkable differences in their karyotypes: E. minor has four metacentric, one metacentric-submetacentric, five submetacentric, one subtelocentric and eight telocentric chromosome pairs, whereas E. directus has three metacentric, two metacentric-submetacentric, six submetacentric, six subtelocentric and two telocentric pairs. Fluorescent in situ hybridisation (FISH) using a major ribosomal DNA probe located the major ribosomal genes on one submetacentric chromosome pair in both species; FISH with a 5S ribosomal DNA (5S rDNA) probe rendered one chromosomal (weak) signal for E. minor and no signal for E. directus, supporting a more dispersed organisation of 5S rDNA compared to the major ribosomal genes. The vertebrate telomeric sequence (TTAGGG) n was located on both ends of each chromosome, and no interstitial signals were detected. In this work, a comparative karyological analysis was also performed between the four Ensis species analysed revealing that the three European species studied so far, namely E. minor, E. siliqua (Linné 1758) and E. magnus Schumacher 1817 show more similarities among them than compared to the American species E. directus. In addition, clear karyotype differences were found between the morphologically similar species E. minor and E. siliqua.

  4. Effects of particle mixing and scattering in the dusty gas flow through moving and stationary cascades of airfoils

    NASA Astrophysics Data System (ADS)

    Tsirkunov, Yu. M.; Romanyuk, D. A.; Panfilov, S. V.

    2011-10-01

    Time-dependent two-dimensional (2D) flow of dusty gas through a set of two cascades of airfoils (blades) has been studied numerically. The first cascade was assumed to move (rotor) and the second one to be immovable (stator). Such a flow can be considered, in some sense, as a flow in the inlet stage of a turbomachine, for example, in the inlet compressor of an aircraft turbojet engine. Dust particle concentration was assumed to be very low, so that the interparticle collisions and the effect of the dispersed phase on the carrier gas were negligible. Flow of the carrier gas was described by full Navier-Stokes equations. In calculations of particle motion, the particles were considered as solid spheres. The particle drag force, transverse Magnus force, and damping torque were taken into account in the model of gas-particle interaction. The impact interaction of particles with blades was considered as frictional and partly elastic. The effects of particle size distribution and particle scattering in the course of particle-blade collisions were investigated. Flow fields of the carrier gas and flow patterns of the particle phase were obtained and discussed.

  5. An Improved Racetrack Structure for Transporting a Skyrmion

    PubMed Central

    Lai, P.; Zhao, G. P.; Tang, H.; Ran, N.; Wu, S. Q.; Xia, J.; Zhang, X.; Zhou, Y.

    2017-01-01

    Magnetic skyrmions are promising building blocks for next generation data storage due to their stability, small size and extremely low currents to drive them, which can be used instead of traditional magnetic domain walls to store information as data bits in metalic racetrack memories. However, skyrmions can drift from the direction of electron flow due to the Magnus force and thus may annihilate at the racetrack edges, resulting in the loss of information. Here we propose a new skyrmion-based racetrack structure by adding high-K materials (materials with high magnetic crystalline anisotropy) at the edges, which confines the skyrmions in the center region of the metalic racetrack efficiently. This design can overcome both the clogging and annihilation of skyrmions according to our micromagnetic simulation, which occur normally for skyrmions moving on a racetrack under small and large driving currents, respectively. Phase diagrams for skyrmion motion on the proposed racetrack with various values of current density and racetrack edge width have been calculated and given, showing that skyrmions can be driven at a high speed (about 300 m/s) in the racetrack under relatively smaller driving currents. This design offers the possiblity of building an ultrafast and energy-efficient skyrmion transport device. PMID:28358009

  6. Delineation of the central melanocortin circuitry controlling the kidneys by a virally mediated transsynaptic tracing study in transgenic mouse model

    PubMed Central

    Liu, Tao Tao; Liu, Bao Wen; He, Zhi Gang; Feng, Li; Liu, San Guang; Xiang, Hong Bing

    2016-01-01

    To examine if brain neurons involved in the efferent control of the kidneys possess melanocortin-4 receptor (MC4-R) and/or tryptophan hydroxylase (TPH). Retrograde tracing pseudorabies virus (PRV)-614 was injected into the kidneys in adult male MC4R-green fluorescent protein (GFP) transgenic mice. After a survival time of 3-7 days, spinal cord and brain were removed and sectioned, and processed for PRV-614 visualization. The neurochemical phenotype of PRV-614-positive neurons was identified using double or triple immunocytochemical labeling against PRV-614, MC4R, or TPH. Double and triple labeling was quantified using microscopy. The majority of PRV-614 immunopositive neurons which also expressed immunoreactivity for MC4R were located in the ipsilateral intermediolateral cell column (IML) of the thoracic spinal cord, the paraventricular nucleus (PVN) of the hypothalamus, and raphe pallidus (RPa), nucleus raphe magnus (NRM) and ventromedial medulla (VMM) of the brainstem. Triple-labeled MC4R/PRV-614/TPH neurons were concentrated in the PVN, RPa, NRM and VMM. These data strongly suggest that central MC4R and TPH are involved in the efferent neuronal control of the kidneys. PMID:27626491

  7. Effectiveness of Selected Fitness Exercises on Stress of Femoral Neck using Musculoskeletal Dynamics Simulations and Finite Element Model.

    PubMed

    Qian, Jing-Guang; Li, Zhaoxia; Zhang, Hong; Bian, Rong; Zhang, Songning

    2014-06-28

    The purpose of the study was to establish a dynamics model and a three-dimensional (3D) finite element model to analyze loading characteristics of femoral neck during walking, squat, single-leg standing, and forward and lateral lunges. One male volunteer performed three trials of the five movements. The 3D kinematic data were captured and imported into the LifeMOD to establish a musculoskeletal dynamics model to obtain joint reaction and muscle forces of iliacus, gluteus medius, gluteus maximus, psoas major and adductor magnus. The loading data LfeMOD were imported and transformed into a hip finite-element model. The results of the finite element femur model showed that stress was localized along the compression arc and the tension arc. In addition, the trabecular bone and tension lines of the Ward's triangle also demonstrated high stress. The compact bone received the greatest peak stress in the forward lunge and the least stress in the squat. However, the spongy bone in the femoral neck region had the greatest stress during the walk and the least stress in the squat. The results from this study indicate that the forward lunge may be an effective method to prevent femoral neck fractures. Walking is another effective and simple method that may improve bone mass of the Ward's triangle and prevent osteoporosis and femoral neck fracture.

  8. The serotonergic anatomy of the developing human medulla oblongata: implications for pediatric disorders of homeostasis.

    PubMed

    Kinney, Hannah C; Broadbelt, Kevin G; Haynes, Robin L; Rognum, Ingvar J; Paterson, David S

    2011-07-01

    The caudal serotonergic (5-HT) system is a critical component of a medullary "homeostatic network" that regulates protective responses to metabolic stressors such as hypoxia, hypercapnia, and hyperthermia. We define anatomically the caudal 5-HT system in the human medulla as 5-HT neuronal cell bodies located in the raphé (raphé obscurus, raphé magnus, and raphé pallidus), extra-raphé (gigantocellularis, paragigantocellularis lateralis, intermediate reticular zone, lateral reticular nucleus, and nucleus subtrigeminalis), and ventral surface (arcuate nucleus). These 5-HT neurons are adjacent to all of the respiratory- and autonomic-related nuclei in the medulla where they are positioned to modulate directly the responses of these effector nuclei. In the following review, we highlight the topography and development of the caudal 5-HT system in the human fetus and infant, and its inter-relationships with nicotinic, GABAergic, and cytokine receptors. We also summarize pediatric disorders in early life which we term "developmental serotonopathies" of the caudal (as well as rostral) 5-HT domain and which are associated with homeostatic imbalances. The delineation of the development and organization of the human caudal 5-HT system provides the critical foundation for the neuropathologic elucidation of its disorders directly in the human brain.

  9. STS-112 Flight Day 10 Highlights

    NASA Technical Reports Server (NTRS)

    2002-01-01

    On Flight Day 10 of the STS-112 mission, its crew (Jeffrey Ashby, Commander; Pamela Melroy, Pilot; David Wolf, Mission Specialist; Piers Sellers, Mission Specialist; Sandra Magnus, Mission Specialist; Fyodor Yurchikhin, Mission Specialist) on the Atlantis and the Expedition 5 crew on the International Space Station (ISS) (Valery Korzun, Commander; Peggy Whitson, Flight Engineer; Sergei Treschev, Flight Engineer) are shown exchanging farewells in the ISS's Destiny Laboratory Module following the completion of a week-long period of docked operations. The Expedition 5 crew is nearing the end of five and a half continuous months aboard the space station. Following the closing of the hatches, the Atlantis Orbiter undocks from the station, and Melroy pilots the shuttle slowly away from the ISS, and engages in a radial fly-around of the station. During the fly-around cameras aboard Atlantis shows ISS from a number of angles. ISS cameras also show Atlantis. There are several shots of each craft with a variety of background settings including the Earth, its limb, and open space. The video concludes with a live interview of Ashby, Melroy and Yurchikhin, still aboard Atlantis, conducted by a reporter on the ground. Questions range from feelings on the conclusion of the mission to the experience of being in space. The primary goal of the mission was the installation of the Integrated Truss Structure S1 on the ISS.

  10. Elimination of high order terms in multiple pulse nuclear magnetic resonance spectroscopy: Application to homonuclear decoupling in solids

    NASA Astrophysics Data System (ADS)

    Hohwy, M.; Nielsen, N. C.

    1997-05-01

    A novel approach to the design of solid state nuclear magnetic resonance multiple pulse experiments is described. Based on time dependent perturbation theory the pulse cycle decoupling principle is extended to fifth order. Furthermore, by analyzing symmetry and commutator relations for high order terms in the average Hamiltonian expansion we introduce so-called z-rotational decoupling accomplished by concatenation of phase shifted pulse cycles. These fundamental tools prove extremely useful for the development of multiple pulse techniques capable of eliminating undesired interactions to high order in the average Hamiltonian expansion. The applicability of the methods is demonstrated by construction of homonuclear multiple-pulse decoupling methods which suppress pure dipolar terms up to fifth order and cross terms between rf inhomogeneity and dipolar coupling to second order in the Magnus expansion. For the dipolar terms this represents an improvement by two orders of magnitude compared to previous homonuclear decoupling sequences. High order truncation decoupling sequences based on the BLEW-12 and magic sandwich pulse cycles are compared to state-of-the-art methods numerically and by preliminary experiments.

  11. Steady motion of skyrmions and domains walls under diffusive spin torques

    NASA Astrophysics Data System (ADS)

    Elías, Ricardo Gabriel; Vidal-Silva, Nicolas; Manchon, Aurélien

    2017-03-01

    We explore the role of the spin diffusion of conducting electrons in two-dimensional magnetic textures (domain walls and skyrmions) with spatial variation of the order of the spin precession length λex. The effect of diffusion reflects in four additional torques that are third order in spatial derivatives of magnetization and bilinear in λex and in the nonadiabatic parameter β'. In order to study the dynamics of the solitons when these diffusive torques are present, we derive the Thiele equation in the limit of steady motion and we compare the results with the nondiffusive limit. When considering a homogenous current these torques increase the longitudinal velocity of transverse domain walls of width Δ by a factor (λex/Δ)2(α/3), α being the magnetic damping constant. In the case of single skyrmions with core radius r0these new contributions tend to increase the Magnus effect in an amount proportional to (λex/r0) 2(1 +2 α β') .

  12. The Flight of a Baseball

    NASA Astrophysics Data System (ADS)

    Nathan, Alan

    2010-03-01

    The trajectory of a baseball moving through the air is very different from the one we teach in our introductory classes in which the only force is that due to gravity. In reality, the aerodynamic drag force (which retards the motion) and the Magnus force on a spinning baseball (which causes the ball to curve) play very important roles that are crucial to many of the subtleties of the game. These forces are governed by three phenomenological quantities: the coefficients of drag, lift, and moment, the latter determining the spin decay time constant. In past years, these quantities were studied mainly in wind tunnel experiments, whereby the forces on the baseball are measured directly. More recently, new tools have been developed that focus on measuring accurate baseball trajectories, from which the forces can be inferred. These tools include high-speed motion analysis, video tracking (the so-called PITCHf/x and HITf/x systems), and Doppler radar tracking via the TrackMan system. In this talk, I will discuss how these new tools work, what they are teaching us about baseball aerodynamics, and how they have the potential to revolutionize the analysis of the game itself.

  13. Why bigger may in fact be better... in the context of table tennis

    NASA Astrophysics Data System (ADS)

    Truscott, Tadd; Pan, Zhao; Belden, Jesse

    2014-11-01

    We submit that table tennis is too fast. Because of the high ball velocities relative to the small table size, players are required to act extremely quickly, often exceeding the limits of human reaction time. Additionally, the Magnus effect resulting from large rotation rates introduces dramatically curved paths and causes rapid direction changes after striking the table or paddle, which effectively reduces reaction time further. Moreover, watching a professional game is often uninteresting and even tiring because the ball is moving too quickly to follow with the naked eye and the action of the players is too subtle to resolve from a distance. These facts isolate table tennis from our quantitatively defined ``fun game club,'' and make it less widely appealing than sports like baseball and soccer. Over the past 100 years, the rules of table tennis have changed several times in an effort to make the game more attractive to players and spectators alike, but the game continues to lose popularity. Here, we experimentally quantify the historic landmark equipment changes of table tennis from a fluid dynamics perspective. Based on theory and observation, we suggest a larger diameter ball for table tennis to make the game more appealing to both spectators and amateur players.

  14. Affinity purification and characterization of a biodegradable plastic-degrading enzyme from a yeast isolated from the larval midgut of a stag beetle, Aegus laevicollis.

    PubMed

    Suzuki, Ken; Sakamoto, Hironori; Shinozaki, Yukiko; Tabata, Jun; Watanabe, Takashi; Mochizuki, Atsushi; Koitabashi, Motoo; Fujii, Takeshi; Tsushima, Seiya; Kitamoto, Hiroko K

    2013-09-01

    Two yeast strains, which have the ability to degrade biodegradable plastic films, were isolated from the larval midgut of a stag beetle, Aegus laevicollis. Both of them are most closely related to Cryptococcus magnus and could degrade biodegradable plastic (BP) films made of poly(butylene succinate) (PBS) and poly(butylene succinate-co-adipate) (PBSA) effectively. A BP-degrading enzyme was purified from the culture broth of one of the isolated strains employing a newly developed affinity purification method based on the binding action of the enzyme to the substrate (emulsified PBSA) and its subsequent degradative action toward the substrate. Partial amino acid sequences of this enzyme suggested that it belongs to the cutinase family, and thus, the enzyme was named CmCut1. It has a molecular mass of 21 kDa and a degradative activity for emulsified PBSA which was significantly enhanced by the simultaneous presence of Ca(2+) or Mg(2+) at a concentration of about 2.5 mM. Its optimal pH was 7.5, and the optimal temperature was 40 °C. It showed a broad substrate specificity for p-nitrophenyl (pNP)-fatty acid esters ranging from pNP-acetate (C2) to pNP-stearate (C18) and films of PBSA, PBS, poly(ε-caprolactone), and poly(lactic acid).

  15. Reversible vector ratchets for skyrmion systems

    NASA Astrophysics Data System (ADS)

    Ma, X.; Reichhardt, C. J. Olson; Reichhardt, C.

    2017-03-01

    We show that ac driven skyrmions interacting with an asymmetric substrate provide a realization of a class of ratchet system which we call a vector ratchet that arises due to the effect of the Magnus term on the skyrmion dynamics. In a vector ratchet, the dc motion induced by the ac drive can be described as a vector that can be rotated clockwise or counterclockwise relative to the substrate asymmetry direction. Up to a full 360∘ rotation is possible for varied ac amplitudes or skyrmion densities. In contrast to overdamped systems, in which ratchet motion is always parallel to the substrate asymmetry direction, vector ratchets allow the ratchet motion to be in any direction relative to the substrate asymmetry. It is also possible to obtain a reversal in the direction of rotation of the vector ratchet, permitting the creation of a reversible vector ratchet. We examine vector ratchets for ac drives applied parallel or perpendicular to the substrate asymmetry direction, and show that reverse ratchet motion can be produced by collective effects. No reversals occur for an isolated skyrmion on an asymmetric substrate. Since a vector ratchet can produce motion in any direction, it could represent a method for controlling skyrmion motion for spintronic applications.

  16. First oilfields of the Central and Northern North Sea

    SciTech Connect

    Swarbrick, R.E. ); Martin, J.A. )

    1991-03-01

    Only 25 years ago the areas now termed the Central and Northern North Sea were the true frontier exploration basins. Stratigraphy and structure were essentially unknown, except inferences drawn from the Mesozoic outcrops of Britain and Denmark. At that time the majority of small British onshore oil fields were reservoired in Paleozoic strata. In the Central North Sea, oil was first discovered in Paleocene deep-water sandstone and Upper Cretaceous chalk reservoirs. The first commercial reserves were proven with the discovery of the Ekofisk field (Upper Cretaceous) in 1969 and Forties field (Paleocene) in 1970, both now classed as giants. Subsequently stratigraphically deeper reservoirs were established, including Jurassic sandstones (Piper field) and Permian carbonates and sandstones (Auk and Argyll fields). Diversity of trap type and reservoir age is now a hallmark of the Central North Sea basin. In the Northern North Sea, the first exploration well in 1971 on the Brent field structure, a true wildcat whose nearest UK well control was 320 mi to the south, found oil in Middle Jurassic deltaic sandstones. A spate of discoveries on similar tilted fault blocks with Middle Jurassic and underlying Triassic alluvial-fluvial sandstone targets followed. Later, Upper Jurassic deep-water sandstones became established as a further significant reservoir with the Brae field and Magnus field discoveries. Original seismic data, well prognoses, and structure maps tell the story of these early discoveries. Public response in Norway and the UK to the emergence of the North Sea oil province on their doorstep will be reviewed.

  17. Rotylenchus castilloi n. sp. (Nematoda: Hoplolaimidae), a new species with long stylet from northern Iran.

    PubMed

    Talezari, Atefeh; Pourjam, Ebrahim; Kheiri, Ahmad; Liébanas, Gracia; Aliramaji, Farzad; Pedram, Majid; Rezaee, Saeed; Atighi, Mohammad Reza

    2015-03-11

    Rotylenchus castilloi n. sp., a new bisexual species is described and illustrated based on morphological, morphometric and molecular data. The new species is characterised by having a hemispherical, continuous lip region with an irregular corncob-like appearance under SEM, very long stylet (62-68 µm), vulva located at 49.7-62.2% of body length from anterior end, with a protruding double epiptygma, a rounded to convex-conoid (rarely bi-lobed) tail with 8-12 annuli and specific sequences of D2-D3 segments of 28S and ITS1-rRNA genes. Differences between the new species and four other species of the genus (R. mesorobustus, R. cazorlaensis, R. magnus and R. jaeni) are discussed. Morphologically, the new species can be separated from these species mostly by its body length, lip region characters, stylet length and location of phasmid. Phylogenetic analyses using 721 bp partial sequences of D2-D3 expansion segments of the 28S and 590 bp ITS1-rRNA genes revealed the new species forming a clade with two isolates of R. eximius and two isolates of R. unisexus, two morphologically unrelated species.

  18. [The yeast community associated with the digestive tract of the German cockroach Blattella germanica L].

    PubMed

    Zheltikova, T M; Glushakova, A M; Alesho, N A

    2011-01-01

    Data on the yeasts colonizing the digestive tract ofa German cockroach have been first obtained. Cockroach cultures are used in the commercial production of allergy vaccines to treat patients sensitized to cockroach allergens. The enteric microflora of the insects can bring nonshared antigens into the composition of the agents manufactured. An investigation established that out of 10 yeast species isolated from the digestive tract of the cockroaches fed sterile food, 6 species (Candida glabrata, Cryptococcus magnus, Debaryomyces hansenii, Metschikowia pulcherrima, Phodo-torula glutinis, Rhodotorula mucilaginosa) were isolated from both the digestive tract and excrements and 4 (Candida oleophila, Candida shehatae, Cryptococcus albidus, Pichia membmnaefciens) were only from the digestive tract. It seems that the yeast is either digested or inactivated in the digestive tract of the insects and loses their capacity to grow When the cockroaches were fed sterile food for a long time (at least a month), all yeasts virtually disappeared from the digestive tract of the insects except for Candida glabrata, C.shehatae, and Rh.mucilaginosa. However, only C.glabrata achieved a great deal (10(7)-10(8) CFU/g) of cockroaches (both imagoes and larvae of 5-7 ages), which statistically significantly decreased by no less than three orders of magnitude in the excrements after passing through the digestive tract.

  19. Brain Injury in Autonomic, Emotional, and Cognitive Regulatory Areas in Patients with Heart Failure

    PubMed Central

    Woo, Mary A.; Kumar, Rajesh; Macey, Paul M.; Fonarow, Gregg C.; Harper, Ronald M.

    2009-01-01

    Background Heart failure (HF) is accompanied by autonomic, emotional, and cognitive deficits, indicating brain alterations. Reduced gray matter volume and isolated white matter infarcts occur in HF, but the extent of damage is unclear. Using magnetic resonance T2 relaxometry, we evaluated the extent of injury across the entire brain in HF. Methods and Results Proton-density and T2-weighted images were acquired from 13 HF (age 54.6 ± 8.3 years; 69% male, LVEF 0.28 ± 0.07) and 49 controls (50.6 ± 7.3 years, 59% male). Whole brain maps of T2 relaxation times were compared at each voxel between groups using analysis of covariance (covariates: age and gender). Higher T2 relaxation values, indicating injured brain areas (p < 0.005), emerged in sites that control autonomic, analgesic, emotional, and cognitive functions (hypothalamus, raphé magnus, cerebellar cortex, deep nuclei and vermis; temporal, parietal, prefrontal, occipital, insular, cingulate, and ventral frontal cortices; corpus callosum; anterior thalamus; caudate nuclei; anterior fornix and hippocampus). No brain areas showed higher T2 values in control vs. HF subjects. Conclusions Brain structural injury emerged in areas involved in autonomic, pain, mood, language, and cognitive function in HF patients. Comorbid conditions accompanying HF may result from neural injury associated with the syndrome. PMID:19327623

  20. The biological soil crusts of the San Nicolas Island: Enigmatic algae from a geographically isolated ecosystem

    USGS Publications Warehouse

    Flechtner, V.R.; Johansen, J.R.; Belnap, J.

    2008-01-01

    Composite soil samples from 7 sites on San Nicolas Island were evaluated quantitatively and qualitatively for the presence of cyanobacteria and eukaryotic microalgae. Combined data demonstrated a rich algal flora with 19 cyanobacterial and 19 eukaryotic microalgal genera being identified, for a total of 56 species. Nine new species were identified and described among the cyanobacteria and the eukaryotic microalgae that were isolated: Leibleinia edaphica, Aphanothece maritima, Chroococcidiopsis edaphica, Cyanosarcina atroveneta, Hassallia californica, Hassallia pseudoramosissima, Microchaete terrestre, Palmellopsis californiens, and Pseudotetracystis compactis. Distinct distributional patterns of algal taxa existed among sites on the island and among soil algal floras of western North America. Some algal taxa appeared to be widely distributed across many desert regions, including Microcoleus vaginatus, Nostoc punctiforme, Nostoc paludosum, and Tolypothrix distorta, Chlorella vulgaris, Diplosphaera cf. chodatii, Myrmecia astigmatica, Myrmecia biatorellae, Hantzschia amphioxys, and Luticola mutica. Some taxa share a distinctly southern distribution with soil algae from southern Arizona, southern California, and Baja California (e.g., Scenedesmus deserticola and Eustigmatos magnus). The data presented herein support the view that the cyanobacterial and microalgal floras of soil crusts possess significant biodiversity, much of it previously undescribed.