WorldWideScience

Sample records for activated flux motion

  1. Active-flux based motion sensorless vector control of biaxial excitation generator/motor for automobiles (BEGA)

    DEFF Research Database (Denmark)

    Coroban-Schramel, Vasile; Boldea, Ion; Andreescu, Gheorghe-Daniel

    2009-01-01

    This paper proposes a novel, active-flux based, motion-sensorless vector control structure for biaxial excitation generator for automobiles (BEGA) for wide speed range operation. BEGA is a hybrid excited synchronous machine having permanent magnets on q-axis and a dc excitation on daxis. Using th...... electrical degrees in less than 2 ms test time....

  2. Critical currents and thermally activated flux motion in high-temperature superconductors

    NARCIS (Netherlands)

    Palstra, T.T.M.; Batlogg, B.; Dover, R.B. van; Schneemeyer, L.F.; Waszczak, J.V.

    1989-01-01

    We have measured the resistance below Tc of single crystals of the high-temperature superconductors Ba2YCu3O7 and Bi2.2Sr2Ca0.8Cu2O8+δ in magnetic fields up to 12 T. The resistive transition of both compounds is dominated by intrinsic dissipation which is thermally activated, resulting in an

  3. Simulation of Field Dependence of Critical Current Densities of Bulk High Tc Superconducting Materials regarding Thermally Activated Flux Motion

    Science.gov (United States)

    Santosh, M.; Naik, S. Pavan Kumar; Koblischka, M. R.

    2017-07-01

    In the upcoming generation, bulk high temperature superconductors (HTS) will play a crucial and a promising role in numerous industrial applications ranging from Maglev trains to magnetic resonance imaging, etc. Especially, the bulk HTS as permanent magnets are suitable due to the fact that they can trap magnetic fields being several orders of magnitude higher than those of the best hard ferromagnets. The bulk HTS LREBa2Cu3O7-δ (LREBCO or LRE-123, LRE: Y, Gd, etc.,) materials could obtain very powerful compact superconducting super-magnets, which can be operated at the cheaper liquid nitrogen temperature or below due to higher critical temperatures (i.e., ∼90 K). As a result, the new advanced technology can be utilized in a more attractive manner for a variety of technological and medical applications which have the capacity to revolutionize the field. An understanding of the magnetic field dependence of the critical current density (J c(H)) is important to develop better adapted materials. To achieve this goal, a variety of Jc (H) behaviours of bulk LREBCO samples were modelled regarding thermally activated flux motion. In essence, the Jc (H) curves follows a certain criterion where an exponential model is applied. However, to fit the complete Jc (H) curve of the LRE-123 samples an unique model is necessary to explain the behavior at low and high fields. The modelling of the various superconducting materials could be understood in terms of the pinning mechanisms.

  4. Correlated electron motion, flux states and superconductivity

    International Nuclear Information System (INIS)

    Lederer, P.; Poilblanc, D.; Rice, T.K.

    1989-01-01

    This paper discusses how, when the on-site correlation is strong, electrons can move by usual hopping only on to empty sites but they can exchange position with their neighbors by a correlated motion. The phase in the former process is fixed and it favors Bloch states. When the concentration of empty sites is small then the latter process dominates and one is free to introduce a phase provided it is chosen to be the same for ↑ and ↓-spin electrons. Since for a partly filled band of non-interacting electrons the introduction of a uniform commensurate flux lowers the energy, the correlated motion can lead to a physical mechanism to generate flux states. These states have a collective gauge variable which is the same for ↑ and ↓-spins and superconducting properties are obtained by expanding around the optimum gauge determined by the usual kinetic energy term. If this latter term has singularities at special fillings then these may affect the superconducting properties

  5. Flux motion and dissipation in high temperature superconductors

    International Nuclear Information System (INIS)

    Tinkham, M.

    1991-01-01

    Two quite different motivations spark the study of flux motion and resistance in the new high-temperature superconductors. Achievement of usefully low resistance at usefully large current densities is the key to most practical applications, but conceptual understanding of the idealized resistive behavior in the O current limit motivates much theoretical work. Some analyses emphasize the pinning of individual flux lines to inhomogeneities in the underlying material; others emphasize the collective aspects of the interacting flux lines, whether liquid, solid, crystalline, or glassy; still others emphasize the concept of percolative Josephson coupling between grains. In this paper an overview is given of these various approaches, their interrelation, and the experiment evidence, including some new results on flux motion in large SNS arrays, treated as a model system

  6. Automatic solar image motion measurements. [electronic disk flux monitoring

    Science.gov (United States)

    Colgate, S. A.; Moore, E. P.

    1975-01-01

    The solar seeing image motion has been monitored electronically and absolutely with a 25 cm telescope at three sites along the ridge at the southern end of the Magdalena Mountains west of Socorro, New Mexico. The uncorrelated component of the variations of the optical flux from two points at opposite limbs of the solar disk was continually monitored in 3 frequencies centered at 0.3, 3 and 30 Hz. The frequency band of maximum signal centered at 3 Hz showed the average absolute value of image motion to be somewhat less than 2sec. The observer estimates of combined blurring and image motion were well correlated with electronically measured image motion, but the observer estimates gave a factor 2 larger value.

  7. IPMSM Motion-Sensorless Direct Torque and Flux Control

    DEFF Research Database (Denmark)

    Pitict, Christian Ilie; Andreescu, Gheorghe-Daniel; Blaabjerg, Frede

    2005-01-01

    The paper presents a rather comprehensive implementation of a wide speed motion-sensorless control of IPMSM drives via direct torque and flux control (DTFC) with space vector modulation (SVM). Signal injection with only one D-module vector filter and phase-locked loop (PLL) observer is used at low...... provides for a smooth current waveform even at 1 rpm. The paper demonstrates through ample experiments a 1750 rpm 1 1 rpm speed range full-loaded with sensorless DTFC-SVM....

  8. Ross sea ice motion, area flux, and deformation

    Science.gov (United States)

    kwok, Ron

    2005-01-01

    The sea ice motion, area export, and deformation of the Ross Sea ice cover are examined with satellite passive microwave and RADARSAT observations. The record of high-resolution synthetic aperture radar (SAR) data, from 1998 and 2000, allows the estimation of the variability of ice deformation at the small scale (10 km) and to assess the quality of the longer record of passive microwave ice motion. Daily and subdaily deformation fields and RADARSAT imagery highlight the variability of motion and deformation in the Ross Sea. With the passive microwave ice motion, the area export at a flux gate positioned between Cape Adare and Land Bay is estimated. Between 1992 and 2003, a positive trend can be seen in the winter (March-November) ice area flux that has a mean of 990 x 103 km2 and ranges from a low of 600 x 103 km2 in 1992 to a peak of 1600 x 103 km2 in 2001. In the mean, the southern Ross Sea produces almost twice its own area of sea ice during the winter. Cross-gate sea level pressure (SLP) gradients explain 60% of the variance in the ice area flux. A positive trend in this gradient, from reanalysis products, suggests a 'spinup' of the Ross Sea Gyre over the past 12 yr. In both the NCEP-NCAR and ERA-40 surface pressure fields, longer-term trends in this gradient and mean SLP between 1979 and 2002 are explored along with positive anomalies in the monthly cross-gate SLP gradient associated with the positive phase of the Southern Hemisphere annular mode and the extrapolar Southern Oscillation.

  9. Flux motion and dissipation in high-temperature superconductors

    International Nuclear Information System (INIS)

    Gray, K.E.; Kim, D.H.

    1991-08-01

    The effects on flux motion and dissipation of interlayer coupling of the Cu-O planes along the c-axis are considered for the high- temperature superconductors (HTS). It is argued that for the highly-anisotropic HTS, the weak interlayer coupling plays a dominant role that can be described by incoherent Josephson tunneling between superconducting Cu-O bi- or tri-layers. In YBa 2 Cu 3 O 7 , the layers are strongly coupled, presumably because the conducting Cu-O chains short circuit the Josephson tunneling, so that these effects are weak or missing

  10. Internal friction of flux motion in Hg-system high-Tc superconductors

    International Nuclear Information System (INIS)

    Tian, W.; Zhu, J.S.; Shao, H.M.; Li, J.; Wang, Y.N.

    1996-01-01

    The internal friction(IF) and modulus as functions of temperature were measured for several Hg-system high-Tc superconductors(Hg1201, Hg1223, Hg1223 doped with Fe and Pb), under the applied magnetic field, with vibrating reed technique. An IF peak associated with flux motion can be found below Tc for all samples. The temperature of the IF peak increases with reducing vibrating amplitude. This amplitude dependence of IF indicates that the flux motion is characterized by nonlinear behavior. No apparent shift of IF peak position can be detected by varying the frequency in the range from 10 2 Hz to 10 3 Hz. Furthermore, the IF peak height satisfies a scaling law Q -1 ∝ω -n . This may be originated from phase transition of flux line lattice(FLL) rather than a thermally activated diffusion process. (orig.)

  11. Vertical motions in an intense magnetic flux tube

    International Nuclear Information System (INIS)

    Roberts, B.; Webb, A.R.

    1978-01-01

    The recent discovery of localised intense magnetic fields in the solar photosphere is one of the major surprises of the past few years. Here the theoretical nature of small amplitude motions in such an intense magnetic flux tube, within which the field strength may reach 2 kG is considered. A systematic derivation of the governing 'expansion' equations is given for a vertical slender tube, taking into account the dependence upon height of the buoyancy, compressibility and magnetic forces. Several special cases (e.g. the isothermal atmosphere) are considered as well as a more realistic, non-isothermal, solar atmosphere. The expansion procedure is shown to give good results in the special case of a uniform basic-state (in which gravity is negligible) and for which a more exact treatment is possible. (Auth.)

  12. Flux motion and dissipation in high-temperature superconductors

    International Nuclear Information System (INIS)

    Gray, K.E.; Kim, D.H.

    1991-01-01

    The effects on flux motion and dissipation of interlayer coupling of the Cu-O planes along the c-axis are considered for the high-temperature superconductors (HTS). It is argued that for the highly-anisotropic HTS, the weak interlayer coupling plays a dominant role that can be described by incoherent Josephson tunneling between superconducting Cu-O bi- or tri-layers. In YBa 2 Cu 3 O 7 , the layers are strongly coupled, presumably because the conducting Cu-O chains short circuit the Josephson tunneling, so that these effects are weak or missing. Recently, the effects of anisotropy and fluctuations on critical current densities, J c (T,H) and the field-induced broadening of resistivity transitions, ρ(T,H), have been studied in high-temperature superconductors (HTS). Although the broadening looks similar for the applied field, H, oriented either parallel to the superconducting Cu-O layers (H parallel ab) or parallel to the c-axis (H parallel c), its width and the detailed shape of ρ(T,H) are different. The explanations given in this paper for the highly anisotropic HTS differ in detail for the two cases, but have a crucial feature in common: they result from fluctuations affecting the Josephson coupling across the interlayer junctions

  13. Prediction of Critical Heat Flux under Rolling Motion

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Jinseok; Lee, Yeongun; Park, Gooncherl [Seoul National Univ., Seoul (Korea, Republic of)

    2013-05-15

    The aim to this paper may be summarized as follows: identify the flow regime compare with existing void-quality relationship and void fraction at OAF derived from the vapor superficial velocity obtained by the churn-to annular flow criterion, develop and evaluate the correlation for accurate prediction of CHF ratio under rolling motion. Experimentally measured CHF results from the previous study were not well-predicted by existing CHF correlations developed for wide range of pressure under rolling motion in vertical tube. Specifically, existing correlations do not account for the dynamic motion parameter, such as tangential and centrifugal force. This study reviewed some existing correlation and experimental studies related to reduction and enhancement of CHF and heat transfer and flow behavior under heaving and rolling motion, and developed a CHF ratio correlation for upward flow vertical tube under rolling motion. Based upon dimensionless groups, equations and interpolation factor, an empirical CHF correlation has been developed which is consistent with experimental data for uniformly heated tubes internally cooled by R-134 under rolling motion. Flow regime was determined through the prediction method for annular flow. Non-dimensional number and function were decided by CHF mechanism of each region. Interaction of LFD and DNB regions is taken into account by means of power interpolation which is reflected void fraction at OAF. The suggested correlation predicted the CHF Ratio with reasonable accuracy, showing an average error of -0.59 and 2.51% for RMS. Rolling motion can affect bubble motion and liquid film behavior complexly by combination of tangential and centrifugal forces and mass flow than heaving motion. Through a search of literature and a comparison of previous CHF ratio results, this work can contribute to the study of boiling heat transfer and CHF for the purpose of enhancement or reduction the CHF of dynamic motion system, such as marine reactor.

  14. Motion of a compact toroid inside a cylindrical flux conserver

    Energy Technology Data Exchange (ETDEWEB)

    Jarboe, T.R.; Henins, I.; Hoida, H.W.; Linford, R.K.; Marshall, J.; Platts, D.A.; Sherwood, A.R.

    1980-10-13

    Compact toroids have been generated in a cylindrical resistive flux conserver. They are observed to rotate so that their major axis is perpendicular to the axis of the flux conserver. Subsequently they remain stationary and their magnetic fields decay with a time constant of about 100 ..mu..s. This is the first observation of the predicted tipping mode and its saturation when no external fields are present. The compact toroids contain toroidal fields and are initially prolate in shape.

  15. Motion of a compact toroid inside a cylindrical flux conserver

    International Nuclear Information System (INIS)

    Jarboe, T.R.; Henins, I.; Hoida, H.W.; Linford, R.K.; Marshall, J.; Platts, D.A.; Sherwood, A.R.

    1980-01-01

    Compact toroids have been generated in a cylindrical resistive flux conserver. They are observed to rotate so that their major axis is perpendicular to the axis of the flux conserver. Subsequently they remain stationary and their magnetic fields decay with a time constant of about 100 μs. This is the first observation of the predicted tipping mode and its saturation when no external fields are present. The compact toroids contain toroidal fields and are initially prolate in shape

  16. Thermally activated flux creep in A15 lattice superconductor microbridges

    International Nuclear Information System (INIS)

    Lykov, A.N.; Prishchepa, S.L.

    1984-01-01

    Current-voltage characteristics were measured for bridges of superconductors having A15 lattices at low voltages; it was found that the characteristics are then exponential, the exponential range being proportional to the resistivity of the films. The existence of thermally activated flux creep in such contacts was demonstrated by experiment. The temperature dependence of the critical bridge current was measured. It was shown that flux creep considerably affects this current. Several parameters of Abrikosov vortex motion were estimated, taking into account the interaction with pinning centers

  17. Vertical motions in an intense magnetic flux tube. Pt. 5

    International Nuclear Information System (INIS)

    Webb, A.R.; Roberts, B.

    1980-01-01

    It is of interest to examine the effect of radiative relaxation on the propagation of waves in an intense magnetic flux tube embedded in a stratified atmosphere. The radiative energy loss (assuming Newton's law of cooling) leads to a decrease in the vertical phase-velocity of the waves, and to a damping of the amplitude for those waves with frequencies greater than the adiabatic value (ωsub(upsilon)) of the tube cut-off frequency. The cut-off frequency is generalized to include the effects of radiative relaxation, and allows the waves to be classified as mainly progressive or mainly damped. The phase-shift between velocity oscillations at two different levels and the phase-difference between temperature and velocity perturbations are compared with the available observations. Radiative dissipation of waves propagating along an intense flux tube may be the cause of the high temperature (and excess brightness) observed in the network. (orig.)

  18. Vertical motions in an intense magnetic flux tube. Pt. 4

    International Nuclear Information System (INIS)

    Webb, A.R.; Roberts, B.

    1980-01-01

    Radiative damping of waves is important in the upper photosphere. It is thus of interest to examine the effect of radiative relaxation on the propagation of waves in an intense magnetic flux tube embedded in a uniform atmosphere. Assuming Newton's law of cooling, it is shown that the radiative energy loss leads to wave damping. Both the damping per wavelength and the damping per period reach maximum value when the sound and radiative timescales are comparable. The stronger the magnetic field, the greater is the damping. (orig.)

  19. Active Brownian motion models and applications to ratchets

    Science.gov (United States)

    Fiasconaro, A.; Ebeling, W.; Gudowska-Nowak, E.

    2008-10-01

    We give an overview over recent studies on the model of Active Brownian Motion (ABM) coupled to reservoirs providing free energy which may be converted into kinetic energy of motion. First, we present an introduction to a general concept of active Brownian particles which are capable to take up energy from the source and transform part of it in order to perform various activities. In the second part of our presentation we consider applications of ABM to ratchet systems with different forms of differentiable potentials. Both analytical and numerical evaluations are discussed for three cases of sinusoidal, staircaselike and Mateos ratchet potentials, also with the additional loads modelled by tilted potential structure. In addition, stochastic character of the kinetics is investigated by considering perturbation by Gaussian white noise which is shown to be responsible for driving the directionality of the asymptotic flux in the ratchet. This stochastically driven directionality effect is visualized as a strong nonmonotonic dependence of the statistics of the right versus left trajectories of motion leading to a net current of particles. Possible applications of the ratchet systems to molecular motors are also briefly discussed.

  20. Flux motion and anisotropy in melt-processed YBa2Cu3O7-δ

    International Nuclear Information System (INIS)

    Koblischka, M.R.; Schuster, Th.; Kuhn, H.; Gluecker, M.; Dalen, A.J.J. van; Griessen, R.; Kronmueller, H.

    1993-01-01

    The melt-processing of YBa 2 Cu 3 O 7-δ - and Bi 2 Sr 2 CaCu 2 O 8+δ -samples offers a promising way to achieve high critical current densities also in bulk materials. This is of main interest for strong current applications of high-T c superconductors. Interesting basic features can also be studied using melt-processed samples, from which good quality crystals can be cut out. For example, such samples make it possible to do measurements in various angular positions without drastically changing the demagnetizing factors along the main crystallographic axes. Usually, most measurements studying the influence of intrinsic pinning have been carried out on thin films (1). To observe flux distributions in superconductors, we use the High Resolution Faraday (HRF) technique. This enables one to local observations of flux distributions, combining a high spatial resolution (∼0.8 μm) with the unique possibility to observe dynamic processes in the flux distribution such as flux motion due to flux creep (2,3). Additionally, torque measurements up to 7 T in the temperature range 10 - 77 K have been carried out on the identical sample for a comparison of the local HRF data with integral critcal current torque data. (orig.)

  1. Classical dynamics with curl forces, and motion driven by time-dependent flux

    International Nuclear Information System (INIS)

    Berry, M V; Shukla, Pragya

    2012-01-01

    For position-dependent forces whose curl is non-zero (‘curl forces’), there is no associated scalar potential and therefore no obvious Hamiltonian or Lagrangean and, except in special cases, no obvious conserved quantities. Nevertheless, the motion is nondissipative (measure-preserving in position and velocity). In a class of planar motions, some of which are exactly solvable, the curl force is directed azimuthally with a magnitude varying with radius, and the orbits are usually spirals. If the curl is concentrated at the origin (for example, the curl force could be an electric field generated by a changing localized magnetic flux, as in the betatron), a Hamiltonian does exist but violates the rotational symmetry of the force. In this case, reminiscent of the Aharonov–Bohm effect, the spiralling is extraordinarily slow. (paper)

  2. Motion of flux transfer events: a test of the Cooling model

    Directory of Open Access Journals (Sweden)

    R. C. Fear

    2007-07-01

    Full Text Available The simple model of reconnected field line motion developed by Cooling et al. (2001 has been used in several recent case studies to explain the motion of flux transfer events across the magnetopause. We examine 213 FTEs observed by all four Cluster spacecraft under a variety of IMF conditions between November 2002 and June 2003, when the spacecraft tetrahedron separation was ~5000 km. Observed velocities were calculated from multi-spacecraft timing analysis, and compared with the velocities predicted by the Cooling model in order to check the validity of the model. After excluding three categories of FTEs (events with poorly defined velocities, a significant velocity component out of the magnetopause surface, or a scale size of less than 5000 km, we were left with a sample of 118 events. 78% of these events were consistent in both direction of motion and speed with one of the two model de Hoffmann-Teller (dHT velocities calculated from the Cooling model (to within 30° and a factor of two in the speed. We also examined the plasma signatures of several magnetosheath FTEs; the electron signatures confirm the hemisphere of connection indicated by the model in most cases. This indicates that although the model is a simple one, it is a useful tool for identifying the source regions of FTEs.

  3. Flux motion in Y-Ba-Cu-O bulk superconductors during pulse field magnetization

    International Nuclear Information System (INIS)

    Yoshizawa, K; Nariki, S; Sakai, N; Murakami, M; Hirabayasi, I; Takizawa, T

    2004-01-01

    We have studied the relationship between the magnetization and temperature change in Y-Ba-Cu-O bulk superconductor during pulse field magnetization (PFM). The flux motion was monitored using both Hall sensors and pick-up coils that are placed on a surface of a Y-Ba-Cu-O disc having dimensions of 15 mm in diameter and 0.95 mm in thickness. The peak value of the field was varied from 0.2 to 0.8 T. The effect of the static bias field was also studied in the range of 0-3 T. The temperature of the sample surface was measured using a resistance temperature sensor. The temperature increased with the magnitude of the applied pulsed magnetic field, and the amount of temperature rise decreased with increasing static bias field

  4. From Cannibalism to Active Motion of Groups

    Science.gov (United States)

    Romanczuk, Pawel; Schimansky-Geier, Lutz

    2008-03-01

    The detailed mechanisms leading to collective dynamics in groups of animals and insect are still poorly understood. A recent study by Simpson et. al. suggests cannibalism as a driving mechanism for coordinated migration of mormon crickets [1]. Based on this result we propose a simple generic model of brownian particles interacting by asymmetric, non-conservative collisions accounting for cannibalistic behavior and the corresponding avoidance strategy. We discuss our model in one and two dimensions and show that a certain type of collisions drives the system out of equilibrium and leads to coordinated active motion of groups.[1] Stephen J. Simpson, Gregory A. Sword, Patrick D. Lorch and Iain D. Couzin: Cannibal crickets on a forced march for protein and salt, PNAS, 103:4152-4156, 2006

  5. Formation and Initiation of Erupting Flux Rope and Embedded Filament Driven by Photospheric Converging Motion

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Xiaozhou; Gan, Weiqun [Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, 210008 Nanjing (China); Xia, Chun; Keppens, Rony, E-mail: zhaoxz@pmo.ac.cn, E-mail: wqgan@pmo.ac.cn, E-mail: chun.xia@kuleuven.be, E-mail: rony.keppens@kuleuven.be [Centre for mathematical Plasma Astrophysics, Department of Mathematics, KU Leuven, Celestijnenlaan 200B, 3001 Leuven (Belgium)

    2017-06-01

    In this paper, we study how a flux rope (FR) is formed and evolves into the corresponding structure of a coronal mass ejection (CME) numerically driven by photospheric converging motion. A two-and-a-half-dimensional magnetohydrodynamics simulation is conducted in a chromosphere-transition-corona setup. The initial arcade-like linear force-free magnetic field is driven by an imposed slow motion converging toward the magnetic inversion line at the bottom boundary. The convergence brings opposite-polarity magnetic flux to the polarity inversion, giving rise to the formation of an FR by magnetic reconnection and eventually to the eruption of a CME. During the FR formation, an embedded prominence gets formed by the levitation of chromospheric material. We confirm that the converging flow is a potential mechanism for the formation of FRs and a possible triggering mechanism for CMEs. We investigate the thermal, dynamical, and magnetic properties of the FR and its embedded prominence by tracking their thermal evolution, analyzing their force balance, and measuring their kinematic quantities. The phase transition from the initiation phase to the acceleration phase of the kinematic evolution of the FR was observed in our simulation. The FR undergoes a series of quasi-static equilibrium states in the initiation phase; while in the acceleration phase the FR is driven by Lorentz force and the impulsive acceleration occurs. The underlying physical reason for the phase transition is the change of the reconnection mechanism from the Sweet–Parker to the unsteady bursty regime of reconnection in the evolving current sheet underneath the FR.

  6. Early capillary flux homogenization in response to neural activation.

    Science.gov (United States)

    Lee, Jonghwan; Wu, Weicheng; Boas, David A

    2016-02-01

    This Brief Communication reports early homogenization of capillary network flow during somatosensory activation in the rat cerebral cortex. We used optical coherence tomography and statistical intensity variation analysis for tracing changes in the red blood cell flux over hundreds of capillaries nearly at the same time with 1-s resolution. We observed that while the mean capillary flux exhibited a typical increase during activation, the standard deviation of the capillary flux exhibited an early decrease that happened before the mean flux increase. This network-level data is consistent with the theoretical hypothesis that capillary flow homogenizes during activation to improve oxygen delivery. © The Author(s) 2015.

  7. Using Kinesthetic Activities to Teach Ptolemaic and Copernican Retrograde Motion

    Science.gov (United States)

    Richards, Ted

    2012-01-01

    This paper describes a method for teaching planetary retrograde motion, and the Ptolemaic and Copernican accounts of retrograde motion, by means of a series kinesthetic learning activities (KLAs). In the KLAs described, the students literally walk through the motions of the planets in both systems. A retrospective statistical analysis shows that…

  8. Calculating the Motion and Direction of Flux Transfer Events with Cluster

    Science.gov (United States)

    Collado-Vega, Y. M.; Sibeck, D. G.

    2012-01-01

    For many years now, the interactions of the solar wind plasma with the Earth's magnetosphere has been one of the most important problems for Space Physics. It is very important that we understand these processes because the high-energy particles and also the solar wind energy that cross the magneto sphere could be responsible for serious damage to our technological systems. The solar wind is inherently a dynamic medium, and the particles interaction with the Earth's magnetosphere can be steady or unsteady. Unsteady interaction include transient processes like bursty magnetic reconnection. Flux Transfer Events (FTEs) are magnetopause signatures that usually occur during transient times of reconnection. They exhibit bipolar signatures in the normal component of the magnetic field. We use multi-point timing analysis to determine the orientation and motion of ux transfer events (FTEs) detected by the four Cluster spacecraft on the high-latitude dayside and flank magnetopause during 2002 and 2003. During these years, the distances between the Cluster spacecraft were greater than 1000 km, providing the tetrahedral configuration needed to select events and determine velocities. Each velocity and location will be examined in detail and compared to the velocities and locations determined by the predictions of the component and antiparallel reconnection models for event formation, orientation, motion, and acceleration for a wide range of spacecraft locations and solar wind conditions.

  9. "Active Flux" DTFC-SVM Sensorless Control of IPMSM

    DEFF Research Database (Denmark)

    Boldea, Ion; Codruta Paicu, Mihaela; Gheorghe-Daniel, Andreescu,

    2009-01-01

    This paper proposes an implementation of a motionsensorless control system in wide speed range based on "active flux" observer, and direct torque and flux control with space vector modulation (DTFC-SVM) for the interior permanent magnet synchronous motor (IPMSM), without signal injection....... The concept of "active flux" (or "torque producing flux") turns all the rotor salient-pole ac machines into fully nonsalient-pole ones. A new function for Lq inductance depending on torque is introduced to model the magnetic saturation. Notable simplification in the rotor position and speed estimation...

  10. Unwinding motion of a twisted active region filament

    Energy Technology Data Exchange (ETDEWEB)

    Yan, X. L.; Xue, Z. K.; Kong, D. F. [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China); Liu, J. H. [Department of Physics, Shijiazhuang University, Shijiazhuang 050035 (China); Xu, C. L. [Yunnan Normal University, Kunming 650092 (China)

    2014-12-10

    To better understand the structures of active region filaments and the eruption process, we study an active region filament eruption in active region NOAA 11082 in detail on 2010 June 22. Before the filament eruption, the opposite unidirectional material flows appeared in succession along the spine of the filament. The rising of the filament triggered two B-class flares at the upper part of the filament. As the bright material was injected into the filament from the sites of the flares, the filament exhibited a rapid uplift accompanying the counterclockwise rotation of the filament body. From the expansion of the filament, we can see that the filament consisted of twisted magnetic field lines. The total twist of the filament is at least 5π obtained by using a time slice method. According to the morphology change during the filament eruption, it is found that the active region filament was a twisted flux rope and its unwinding motion was like a solar tornado. We also find that there was a continuous magnetic helicity injection before and during the filament eruption. It is confirmed that magnetic helicity can be transferred from the photosphere to the filament. Using the extrapolated potential fields, the average decay index of the background magnetic fields over the filament is 0.91. Consequently, these findings imply that the mechanism of solar filament eruption could be due to the kink instability and magnetic helicity accumulation.

  11. Charged particle motion in a time-dependent flux-driven ring: an exactly solvable model

    International Nuclear Information System (INIS)

    Luan, P-G; Tang, C-S

    2007-01-01

    We consider a charged particle driven by a time-dependent flux threading a quantum ring. The dynamics of the charged particle is investigated using a classical treatment, a Fourier expansion technique, a time-evolution method, and the Lewis-Riesenfeld approach. We have shown that, by properly managing the boundary conditions, a time-dependent wavefunction can be obtained using a general non-Hermitian time-dependent invariant, which is a specific linear combination of initial angular-momentum and azimuthal-angle operators. It is shown that the linear invariant eigenfunction can be realized as a Gaussian-type wavepacket with a peak moving along the classical angular trajectory, while the distribution of the wavepacket is determined by the ratio of the coefficient of the initial angle to that of the initial canonical angular momentum. From the topologically nontrivial nature as well as the classical trajectory and angular momentum, one can determine the dynamical motion of the wavepacket. It should be noted that the peak position is no longer an expectation value of the angle operator, and hence the Ehrenfest theorem is not directly applicable in such a topologically nontrivial system

  12. Using Kinesthetic Activities to Teach Ptolemaic and Copernican Retrograde Motion

    Science.gov (United States)

    Richards, Ted

    2012-06-01

    This paper describes a method for teaching planetary retrograde motion, and the Ptolemaic and Copernican accounts of retrograde motion, by means of a series kinesthetic learning activities (KLAs). In the KLAs described, the students literally walk through the motions of the planets in both systems. A retrospective statistical analysis shows that students who participated in these activities performed better on examination questions pertaining to retrograde motion than students who did not. Potential explanations for this result, including the breaking of classroom routine, the effect of body movement on conceptual memory, and egocentric spatial proprioception, are considered.

  13. Transendothelial albumin flux: evidence against active transport of albumin

    International Nuclear Information System (INIS)

    Siflinger-Birnboim, A.; Del Vecchio, P.J.; Cooper, J.A.; Malik, A.B.

    1986-01-01

    The authors studied whether albumin is actively transported across cultured pulmonary endothelium by comparing the transendothelial flux of 125 I-albumin from the luminal-to-abluminal side to the flux from the abluminal-to-luminal side. Bovine pulmonary artery endothelial cells were grown to confluence on gelatinized polycarbonated filters separating abluminal from luminal compartments. Each compartment had an albumin concentration of 1 g/100 ml to equalize oncotic pressure gradients. The effect of hydrostatic pressure was eliminated by maintaining an equal level of fluid in both compartments. The transendothelial flux of albumin across the monolayer was measured by placing 125 I-albumin tracer either on the luminal or the abluminal side. Equal fluxes of 125 I-albumin from luminal-to-abluminal side and from abluminal-to-luminal side were observed. The results indicate that the pulmonary endothelium behaves symmetrically for albumin, indicating the absence of active transport of albumin

  14. Successive Homologous Coronal Mass Ejections Driven by Shearing and Converging Motions in Solar Active Region NOAA 12371

    International Nuclear Information System (INIS)

    Vemareddy, P.

    2017-01-01

    We study the magnetic field evolution in AR 12371, related to its successive eruptive nature. During the disk transit of seven days, the active region (AR) launched four sequential fast coronal mass ejections (CMEs), which are associated with long duration M-class flares. Morphological study delineates a pre-eruptive coronal sigmoid structure above the polarity inversion line (PIL) similar to Moore et al.’s study. The velocity field derived from tracked magnetograms indicates persistent shear and converging motions of polarity regions about the PIL. While these shear motions continue, the crossed arms of two sigmoid elbows are being brought to interaction by converging motions at the middle of the PIL, initiating the tether-cutting reconnection of field lines and the onset of the CME explosion. The successive CMEs are explained by a cyclic process of magnetic energy storage and release referred to as “sigmoid-to-arcade-to-sigmoid” transformation driven by photospheric flux motions. Furthermore, the continued shear motions inject helicity flux with a dominant negative sign, which contributes to core field twist and its energy by building a twisted flux rope (FR). After a limiting value, the excess coronal helicity is expelled by bodily ejection of the FR, which is initiated by some instability as realized by intermittent CMEs. This AR is in contrast with the confined AR 12192 with a predominant negative sign and larger helicity flux, but much weaker (−0.02 turns) normalized coronal helicity content. While predominant signed helicity flux is a requirement for CME eruption, our study suggests that the magnetic flux normalized helicity flux is a necessary condition accommodating the role of background flux and appeals to a further study of a large sample of ARs.

  15. Successive Homologous Coronal Mass Ejections Driven by Shearing and Converging Motions in Solar Active Region NOAA 12371

    Energy Technology Data Exchange (ETDEWEB)

    Vemareddy, P., E-mail: vemareddy@iiap.res.in [Indian Institute of Astrophysics, II Block, Koramangala, Bengalure-560034 (India)

    2017-08-10

    We study the magnetic field evolution in AR 12371, related to its successive eruptive nature. During the disk transit of seven days, the active region (AR) launched four sequential fast coronal mass ejections (CMEs), which are associated with long duration M-class flares. Morphological study delineates a pre-eruptive coronal sigmoid structure above the polarity inversion line (PIL) similar to Moore et al.’s study. The velocity field derived from tracked magnetograms indicates persistent shear and converging motions of polarity regions about the PIL. While these shear motions continue, the crossed arms of two sigmoid elbows are being brought to interaction by converging motions at the middle of the PIL, initiating the tether-cutting reconnection of field lines and the onset of the CME explosion. The successive CMEs are explained by a cyclic process of magnetic energy storage and release referred to as “sigmoid-to-arcade-to-sigmoid” transformation driven by photospheric flux motions. Furthermore, the continued shear motions inject helicity flux with a dominant negative sign, which contributes to core field twist and its energy by building a twisted flux rope (FR). After a limiting value, the excess coronal helicity is expelled by bodily ejection of the FR, which is initiated by some instability as realized by intermittent CMEs. This AR is in contrast with the confined AR 12192 with a predominant negative sign and larger helicity flux, but much weaker (−0.02 turns) normalized coronal helicity content. While predominant signed helicity flux is a requirement for CME eruption, our study suggests that the magnetic flux normalized helicity flux is a necessary condition accommodating the role of background flux and appeals to a further study of a large sample of ARs.

  16. Determination of average activating thermal neutron flux in bulk samples

    International Nuclear Information System (INIS)

    Doczi, R.; Csikai, J.; Doczi, R.; Csikai, J.; Hassan, F. M.; Ali, M.A.

    2004-01-01

    A previous method used for the determination of the average neutron flux within bulky samples has been applied for the measurements of hydrogen contents of different samples. An analytical function is given for the description of the correlation between the activity of Dy foils and the hydrogen concentrations. Results obtained by the activation and the thermal neutron reflection methods are compared

  17. INITIATION AND ERUPTION PROCESS OF MAGNETIC FLUX ROPE FROM SOLAR ACTIVE REGION NOAA 11719 TO EARTH-DIRECTED CME

    Energy Technology Data Exchange (ETDEWEB)

    Vemareddy, P. [Udaipur Solar Observatory, Physical Research Laboratory, Badi Road, Dewali, Udaipur 313 001 (India); Zhang, J., E-mail: vema@prl.res.in [School of Physics, Astronomy and Computational Sciences, George Mason University, Fairfax, VA 22030 (United States)

    2014-12-20

    An eruption event launched from the solar active region (AR) NOAA 11719 is investigated based on coronal EUV observations and photospheric magnetic field measurements obtained from the Solar Dynamic Observatory. The AR consists of a filament channel originating from a major sunspot and its south section is associated with an inverse-S sigmoidal system as observed in Atmospheric Imaging Assembly passbands. We regard the sigmoid as the main body of the flux rope (FR). There also exists a twisted flux bundle crossing over this FR. This overlying flux bundle transforms in shape similar to kink-rise evolution, which corresponds with the rise motion of the FR. The emission measure and temperature along the FR exhibits an increasing trend with its rising motion, indicating reconnection in the thinning current sheet underneath the FR. Net magnetic flux of the AR, evaluated at north and south polarities, showed decreasing behavior whereas the net current in these fluxes exhibits an increasing trend. Because the negative (positive) flux has a dominant positive (negative) current, the chirality of AR flux system is likely negative (left handed) in order to be consistent with the chirality of inverse S-sigmoidal FR. This analysis of magnetic fields of the source AR suggests that the cancelling fluxes are prime factors of the monotonous twisting of the FR system, reaching to a critical state to trigger kink instability and rise motion. This rise motion may have led to the onset of the torus instability, resulting in an Earth-directed coronal mass ejection, and the progressive reconnection in the thinning current sheet beneath the rising FR led to the M6.5 flare.

  18. INITIATION AND ERUPTION PROCESS OF MAGNETIC FLUX ROPE FROM SOLAR ACTIVE REGION NOAA 11719 TO EARTH-DIRECTED CME

    International Nuclear Information System (INIS)

    Vemareddy, P.; Zhang, J.

    2014-01-01

    An eruption event launched from the solar active region (AR) NOAA 11719 is investigated based on coronal EUV observations and photospheric magnetic field measurements obtained from the Solar Dynamic Observatory. The AR consists of a filament channel originating from a major sunspot and its south section is associated with an inverse-S sigmoidal system as observed in Atmospheric Imaging Assembly passbands. We regard the sigmoid as the main body of the flux rope (FR). There also exists a twisted flux bundle crossing over this FR. This overlying flux bundle transforms in shape similar to kink-rise evolution, which corresponds with the rise motion of the FR. The emission measure and temperature along the FR exhibits an increasing trend with its rising motion, indicating reconnection in the thinning current sheet underneath the FR. Net magnetic flux of the AR, evaluated at north and south polarities, showed decreasing behavior whereas the net current in these fluxes exhibits an increasing trend. Because the negative (positive) flux has a dominant positive (negative) current, the chirality of AR flux system is likely negative (left handed) in order to be consistent with the chirality of inverse S-sigmoidal FR. This analysis of magnetic fields of the source AR suggests that the cancelling fluxes are prime factors of the monotonous twisting of the FR system, reaching to a critical state to trigger kink instability and rise motion. This rise motion may have led to the onset of the torus instability, resulting in an Earth-directed coronal mass ejection, and the progressive reconnection in the thinning current sheet beneath the rising FR led to the M6.5 flare

  19. SNS Sample Activation Calculator Flux Recommendations and Validation

    Energy Technology Data Exchange (ETDEWEB)

    McClanahan, Tucker C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Spallation Neutron Source (SNS); Gallmeier, Franz X. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Spallation Neutron Source (SNS); Iverson, Erik B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Spallation Neutron Source (SNS); Lu, Wei [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Spallation Neutron Source (SNS)

    2015-02-01

    The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL) uses the Sample Activation Calculator (SAC) to calculate the activation of a sample after the sample has been exposed to the neutron beam in one of the SNS beamlines. The SAC webpage takes user inputs (choice of beamline, the mass, composition and area of the sample, irradiation time, decay time, etc.) and calculates the activation for the sample. In recent years, the SAC has been incorporated into the user proposal and sample handling process, and instrument teams and users have noticed discrepancies in the predicted activation of their samples. The Neutronics Analysis Team validated SAC by performing measurements on select beamlines and confirmed the discrepancies seen by the instrument teams and users. The conclusions were that the discrepancies were a result of a combination of faulty neutron flux spectra for the instruments, improper inputs supplied by SAC (1.12), and a mishandling of cross section data in the Sample Activation Program for Easy Use (SAPEU) (1.1.2). This report focuses on the conclusion that the SAPEU (1.1.2) beamline neutron flux spectra have errors and are a significant contributor to the activation discrepancies. The results of the analysis of the SAPEU (1.1.2) flux spectra for all beamlines will be discussed in detail. The recommendations for the implementation of improved neutron flux spectra in SAPEU (1.1.3) are also discussed.

  20. Orbit-averaged quantities, the classical Hellmann-Feynman theorem, and the magnetic flux enclosed by gyro-motion

    Energy Technology Data Exchange (ETDEWEB)

    Perkins, R. J., E-mail: rperkins@pppl.gov; Bellan, P. M. [Applied Physics and Materials Science, California Institute of Technology, Pasadena, California 91125 (United States)

    2015-02-15

    Action integrals are often used to average a system over fast oscillations and obtain reduced dynamics. It is not surprising, then, that action integrals play a central role in the Hellmann-Feynman theorem of classical mechanics, which furnishes the values of certain quantities averaged over one period of rapid oscillation. This paper revisits the classical Hellmann-Feynman theorem, rederiving it in connection to an analogous theorem involving the time-averaged evolution of canonical coordinates. We then apply a modified version of the Hellmann-Feynman theorem to obtain a new result: the magnetic flux enclosed by one period of gyro-motion of a charged particle in a non-uniform magnetic field. These results further demonstrate the utility of the action integral in regards to obtaining orbit-averaged quantities and the usefulness of this formalism in characterizing charged particle motion.

  1. Flux

    DEFF Research Database (Denmark)

    Ravn, Ib

    . FLUX betegner en flyden eller strømmen, dvs. dynamik. Forstår man livet som proces og udvikling i stedet for som ting og mekanik, får man et andet billede af det gode liv end det, som den velkendte vestlige mekanicisme lægger op til. Dynamisk forstået indebærer det gode liv den bedst mulige...... kanalisering af den flux eller energi, der strømmer igennem os og giver sig til kende i vore daglige aktiviteter. Skal vores tanker, handlinger, arbejde, samvær og politiske liv organiseres efter stramme og faste regelsæt, uden slinger i valsen? Eller skal de tværtimod forløbe ganske uhindret af regler og bånd...

  2. Measurement of a thermal neutron flux using air activation; Mesure de flux de neutrons thermiques par activation d'air

    Energy Technology Data Exchange (ETDEWEB)

    Guyonvarh, M; Lecomte, P; Le Meur, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1967-07-01

    It is necessary to know, in irradiation loops, the thermal neutron flux after the irradiation device has been introduced and without being obliged to wait for the discharge of this device. In order to measure the flux and to control it continuously, one possible method is to place in the flux a coiled steel tube through which air passes. By measuring the activity of argon 41, and with a knowledge of the flow rate and the temperature of the air, it is possible to calculate the flux. An air-circulation flux controller is described and the relationship between the flux and the count rate is established The accuracy of an absolute measurement is about 14 per cent; that of a relative measurement is about 3 per cent. The measurement can be carried out equally well whether the reactor is operating at maximum or at low power. The measurement range goes from 10{sup 9} to lO{sup 15} n.cm{sup -2}.sec{sup -1}, and it would be possible after a few modifications to measure fluxes between 10{sup 5} and 10{sup 15} n.cm{sup -2}.sec{sup -1}. Finally, the method is very safe to operate: there is little risk of irradiation because of the low specific activity of the argon-41 formed, and no risk of contamination because the decay product of argon-41 is stable. This method, which is now being used in loops, is thus very practical. (authors) [French] Sur des boucles d'irradiation il est necessaire de connaitre le flux de neutrons thermiques apres mise en place du dispositif d'irradiation et sans etre oblige d'attendre le detournement de ce dispositif. Pour mesurer le flux et le controler en permanence, une methode consiste a placer sous flux un serpentin en acier dans lequel on fait circuler de l'air. La mesure d'activite d'argon 41 permet de calculer le flux, connaissant le debit et la temperature de l'air. Un controleur de flux par circulation d'air est decrit et la relation entre le flux et le taux de comptage est etablie. La precision d'une mesure absolue est de l'ordre de 14 pour

  3. Companion classroom activities for "stop faking it!" force and motion

    CERN Document Server

    Robertson, William C

    2011-01-01

    Never has it been so easy for educators to learn to teach physical science with confidence. Award-winning author Bill Robertson launched his bestselling Stop Faking It! series in 2002 with Force and Motion--offering elementary and middle school teachers a jargon-free way to learn the background for teaching physical science with confidence. Combining easy-to-understand if irreverent explanations and quirky diagrams, Stop Faking It! Force and Motion helped thousands of teachers, parents, and homeschoolers conquer topics from Newton s laws to the physics of space travel. Now Companion Classroom Activities for Stop Faking It! Force and Motion proves an ideal supplement to the original book or a valuable resource of its own. The hands-on activities and highly readable explanations allow students to first investigate concepts, then discuss learned concepts, and finally apply the concepts to everyday situations. Robertson's wit and humor are sure to keep students and teachers entertained while they tackle topics ...

  4. Stochastic line motion and stochastic flux conservation for nonideal hydromagnetic models

    International Nuclear Information System (INIS)

    Eyink, Gregory L.

    2009-01-01

    We prove that smooth solutions of nonideal (viscous and resistive) incompressible magnetohydrodynamic (MHD) equations satisfy a stochastic law of flux conservation. This property implies that the magnetic flux through a surface is equal to the average of the magnetic fluxes through an ensemble of surfaces advected backward in time by the plasma velocity perturbed with a random white noise. Our result is an analog of the well-known Alfven theorem of ideal MHD and is valid for any value of the magnetic Prandtl number. A second stochastic conservation law is shown to hold at unit Prandtl number, a random version of the generalized Kelvin theorem derived by Bekenstein and Oron for ideal MHD. These stochastic conservation laws are not only shown to be consequences of the nonideal MHD equations but are proved in fact to be equivalent to those equations. We derive similar results for two more refined hydromagnetic models, Hall MHD and the two-fluid plasma model, still assuming incompressible velocities and isotropic transport coefficients. Finally, we use these results to discuss briefly the infinite-Reynolds-number limit of hydromagnetic turbulence and to support the conjecture that flux conservation remains stochastic in that limit.

  5. Examination of faults active motion on buried pipelines | Parish ...

    African Journals Online (AJOL)

    ... lateral spreading, landslides and slope failures. Since the pipelines are widely spread, and in some areas necessarily cross through the areas with faults, therefore, improvement study of pipelines in areas with faults is very important. This article explores faults active motion on buried pipelines. Keywords: water utilities ...

  6. A combined system for measuring animal motion activities.

    Science.gov (United States)

    Young, M S; Young, C W; Li, Y C

    2000-01-31

    In this study, we have developed a combined animal motion activity measurement system that combines an infrared light matrix subsystem with an ultrasonic phase shift subsystem for animal activity measurement. Accordingly, in conjunction with an IBM PC/AT compatible personal computer, the combined system has the advantages of both infrared and ultrasonic subsystems. That is, it can at once measure and directly analyze detailed changes in animal activity ranging from locomotion to tremor. The main advantages of this combined system are that it features real time data acquisition with the option of animated real time or recorded display/playback of the animal's motion. Additionally, under the multi-task operating condition of IBM PC, it can acquire and process behavior using both IR and ultrasound systems simultaneously. Traditional systems have had to make separate runs for gross and fine movement recording. This combined system can be profitably employed for normative behavioral activity studies and for neurological and pharmacological research.

  7. Active Control Does Not Eliminate Motion-Induced Illusory Displacement

    Directory of Open Access Journals (Sweden)

    Ian M. Thornton

    2011-05-01

    Full Text Available When the sine-wave grating of a Gabor patch drifts to the left or right, the perceived position of the entire object is shifted in the direction of local motion. In the current work we explored whether active control of the physical position of the patch overcomes such motion induced illusory displacement. In Experiment 1 we created a simple computer game and asked participants to continuously guide a Gabor patch along a randomly curving path using a joystick. When the grating inside the Gabor patch was stationary, participants could perform this task without error. When the grating drifted to either left or right, we observed systematic errors consistent with previous reports of motion-induced illusory displacement. In Experiment 2 we created an iPad application where the built-in accelerometer tilt control was used to steer the patch through as series of “gates”. Again, we observed systematic guidance errors that depended on the direction and speed of local motion. In conclusion, we found no evidence that participants could adapt or compensate for illusory displacement given active control of the target.

  8. The Importance of Spatiotemporal Information in Biological Motion Perception: White Noise Presented with a Step-like Motion Activates the Biological Motion Area.

    Science.gov (United States)

    Callan, Akiko; Callan, Daniel; Ando, Hiroshi

    2017-02-01

    Humans can easily recognize the motion of living creatures using only a handful of point-lights that describe the motion of the main joints (biological motion perception). This special ability to perceive the motion of animate objects signifies the importance of the spatiotemporal information in perceiving biological motion. The posterior STS (pSTS) and posterior middle temporal gyrus (pMTG) region have been established by many functional neuroimaging studies as a locus for biological motion perception. Because listening to a walking human also activates the pSTS/pMTG region, the region has been proposed to be supramodal in nature. In this study, we investigated whether the spatiotemporal information from simple auditory stimuli is sufficient to activate this biological motion area. We compared spatially moving white noise, having a running-like tempo that was consistent with biological motion, with stationary white noise. The moving-minus-stationary contrast showed significant differences in activation of the pSTS/pMTG region. Our results suggest that the spatiotemporal information of the auditory stimuli is sufficient to activate the biological motion area.

  9. Manifestation of solar activity in solar wind particle flux density

    International Nuclear Information System (INIS)

    Kovalenko, V.A.

    1988-01-01

    An analysis has been made of the origin of long-term variations in flux density of solar wind particles (nv) for different velocity regimes. The study revealed a relationship of these variations to the area of the polar coronal holes (CH). It is shown that within the framework of the model under development, the main longterm variations of nv are a result of the latitude redistribution of the solar wind mass flux in the heliosphere and are due to changes in the large-scale geometry of the solar plasma flow in the corona. A study has been made of the variations of nv for high speed solar wind streams. It is found that nv in high speed streams which are formed in CH, decreases from minimum to maximum solar activity. The analysis indicates that this decrease is attributable to the magnetic field strength increase in coronal holes. It has been found that periods of rapid global changes of background magnetic fields on the Sun are accompanied by a reconfiguration of coronal magnetic fields, rapid changes in the length of quiescent filaments, and by an increase in the density of the particle flux of a high speed solar wind. It has been established that these periods precede the formation of CH, corresponding to the increase in solar wind velocity near the Earth and to enhancement of the level of geomagnetic disturbance. (author)

  10. Hybrid magnetic mechanism for active locomotion based on inchworm motion

    International Nuclear Information System (INIS)

    Kim, Sung Hoon; Hashi, Shuichiro; Ishiyama, Kazushi

    2013-01-01

    Magnetic robots have been studied in the past. Insect-type micro-robots are used in various biomedical applications; researchers have developed inchworm micro-robots for endoscopic use. A biological inchworm has a looping locomotion gait. However, most inchworm micro-robots depend on a general bending, or bellows, motion. In this paper, we introduce a new robotic mechanism using magnetic force and torque control in a rotating magnetic field for a looping gait. The proposed robot is controlled by the magnetic torque, attractive force, and body mechanisms (two stoppers, flexible body, and different frictional legs). The magnetic torque generates a general bending motion. In addition, the attractive force and body mechanisms produce the robot’s looping motion within a rotating magnetic field and without the use of an algorithm for field control. We verified the device’s performance and analyzed the motion through simulations and various experiments. The robot mechanism can be applied to active locomotion for various medical robots, such as wireless endoscopes. (technical note)

  11. Motion Sensor Reactivity in Physically Active Young Adults

    Science.gov (United States)

    Behrens, Timothy K.; Dinger, Mary K.

    2007-01-01

    The purpose of this study was to examine whether young adults changed their physical activity (PA) behavior when wearing motion sensors. PA patterns of 119 young adults (M age = 20.82 years, SD = 1.50, M body mass index = 23.93 kg/m[superscript 2] , SD = 4.05) were assessed during 2 consecutive weeks. In Week 1, participants wore an accelerometer.…

  12. Effects of parabolic motion on an isothermal vertical plate with constant mass flux

    Directory of Open Access Journals (Sweden)

    R. Muthucumaraswamy

    2014-12-01

    Full Text Available An analytical study of free convection flow near a parabolic started infinite vertical plate with isothermal in the presence of uniform mass flux was considered. The mathematical model is reduced to a system of linear partial differential equations for the velocity, the concentration and the temperature; the closed form exact solutions were obtained by the Laplace transform technique. The velocity, temperature and concentration profiles for the different parameters as thermal Grashof number Gr, mass Grashof number Gc, Prandtl number Pr, Schmidt number Sc and time t were graphed and the numerical values for the skin friction were as tabulated. It is observed that the velocity is enhanced as the time increased and the velocity is decreased as the Prandtl number increased.

  13. Motion sickness and tilts of the inertial force environment: active suspension systems vs. active passengers

    NARCIS (Netherlands)

    Golding, J.F.; Bles, W.; Bos, J.E.; Haynes, T.; Gresty, M.A.

    2003-01-01

    Maneuvering in vehicles exposes occupants to low frequency forces (<1 Hz) which can provoke motion sickness. Hypothesis: Aligning with the tilting inertial resultant (gravity + imposed horizontal acceleration: gravito-inertial force (GIF)) may reduce motion sickness when tilting is either 'active'

  14. Autonomous Motion Learning for Intra-Vehicular Activity Space Robot

    Science.gov (United States)

    Watanabe, Yutaka; Yairi, Takehisa; Machida, Kazuo

    Space robots will be needed in the future space missions. So far, many types of space robots have been developed, but in particular, Intra-Vehicular Activity (IVA) space robots that support human activities should be developed to reduce human-risks in space. In this paper, we study the motion learning method of an IVA space robot with the multi-link mechanism. The advantage point is that this space robot moves using reaction force of the multi-link mechanism and contact forces from the wall as space walking of an astronaut, not to use a propulsion. The control approach is determined based on a reinforcement learning with the actor-critic algorithm. We demonstrate to clear effectiveness of this approach using a 5-link space robot model by simulation. First, we simulate that a space robot learn the motion control including contact phase in two dimensional case. Next, we simulate that a space robot learn the motion control changing base attitude in three dimensional case.

  15. Active superconducting DC fault current limiter based on flux compensation

    International Nuclear Information System (INIS)

    Shi Jing; Tang Yuejin; Wang, Chen; Zhou Yusheng; Li Jingdong; Ren Li; Chen Shijie

    2006-01-01

    With the extensive application of DC power systems, suppression of DC fault current is an important subject that guarantees system security. This paper presents an active superconducting DC fault current limiter (DC-SFCL) based on flux compensation. The DC-SFCL is composed of two superconducting windings wound on a single iron core, the primary winding is in series with DC power system, and the second winding is connected with AC power system through a PWM converter. In normal operating state, the flux in the iron core is compensated to zero, and the SFCL has no influence on DC power system. In the case of DC system accident, through regulating the active power exchange between the SFCL's second winding and the AC power system, the current on the DC side can be limited to different level complying with the system demand. Moreover, the PWM converter that interface the DC system and AC system can be controlled as a reactive power source to supply voltage support for the AC side, which has little influence on the performance of SFCL. Using MATLAB SIMULINK, the mathematic model of the DC-SFCL is created, simulation results validate the dynamics of system, and the performance of DC-SFCL is confirmed

  16. Photothermally activated motion and ignition using aluminum nanoparticles

    International Nuclear Information System (INIS)

    Abboud, Jacques E.; Chong Xinyuan; Zhang Mingjun; Zhang Zhili; Jiang Naibo; Roy, Sukesh; Gord, James R.

    2013-01-01

    The aluminum nanoparticles (Al NPs) are demonstrated to serve as active photothermal media, to enhance and control local photothermal energy deposition via the photothermal effect activated by localized surface plasmon resonance (LSPR) and amplified by Al NPs oxidation. The activation source is a 2-AA-battery-powered xenon flash lamp. The extent of the photothermally activated movement of Al NPs can be ∼6 mm. Ignition delay can be ∼0.1 ms. Both scanning electron microscopy and energy-dispersive X-ray spectroscopy measurements of motion-only and after-ignition products confirm significant Al oxidation occurs through sintering and bursting after the flash exposure. Simulations suggest local heat generation is enhanced by LSPR. The positive-feedback effects from the local heat generation amplified by Al oxidation produce a large increase in local temperature and pressure, which enhances movement and accelerates ignition.

  17. Comparison of the Danish Physical Activity Questionnaire with a validated position and motion instrument

    DEFF Research Database (Denmark)

    Matthiessen, Jeppe; Biltoft-Jensen, Anja Pia; Rasmussen, Lone Banke

    2008-01-01

    Objective To compare the Danish Physical Activity Questionnaire (DPAQ) estimating physical activity energy expenditure (PAEE) and physical activity level (PAL) and the pattern of physical activity (including health-related physical activity) with measurements from a validated position and motion ...

  18. Bayesian calibration of reactor neutron flux spectrum using activation detectors measurements: Application to CALIBAN reactor

    International Nuclear Information System (INIS)

    Cartier, J.; Casoli, P.; Chappert, F.

    2013-01-01

    In this paper, we present calibration methods in order to estimate reactor neutron flux spectrum and its uncertainties by using integral activation measurements. These techniques are performed using Bayesian and MCMC framework. These methods are applied to integral activation experiments in the cavity of the CALIBAN reactor. We estimate the neutron flux and its related uncertainties. The originality of this work is that these uncertainties take into account measurements uncertainties, cross-sections uncertainties and model error. In particular, our results give a very good approximation of the total flux and indicate that neutron flux from MCNP simulation for energies above about 5 MeV seems to overestimate the 'real flux'. (authors)

  19. Variability of the Lyman alpha flux with solar activity

    International Nuclear Information System (INIS)

    Lean, J.L.; Skumanich, A.

    1983-01-01

    A three-component model of the solar chromosphere, developed from ground based observations of the Ca II K chromospheric emission, is used to calculate the variability of the Lyman alpha flux between 1969 and 1980. The Lyman alpha flux at solar minimum is required in the model and is taken as 2.32 x 10 11 photons/cm 2 /s. This value occurred during 1975 as well as in 1976 near the commencement of solar cycle 21. The model predicts that the Lyman alpha flux increases to as much as 5 x 10 11 photons/cm 2 /s at the maximum of the solar cycle. The ratio of the average fluxes for December 1979 (cycle maximum) and July 1976 (cycle minimum) is 1.9. During solar maximum the 27-day solar rotation is shown to cause the Lyman alpha flux to vary by as much as 40% or as little as 5%. The model also shows that the Lyman alpha flux varies over intermediate time periods of 2 to 3 years, as well as over the 11-year sunspot cycle. We conclude that, unlike the sunspot number and the 10.7-cm radio flux, the Lyman alpha flux had a variability that was approximately the same during each of the past three cycles. Lyman alpha fluxes calculated by the model are consistent with measurements of the Lyman alpha flux made by 11 of a total of 14 rocket experiments conducted during the period 1969--1980. The model explains satisfactorily the absolute magnitude, long-term trends, and the cycle variability seen in the Lyman alpha irradiances by the OSO 5 satellite experiment. The 27-day variability observed by the AE-E satellite experiment is well reproduced. However, the magntidue of the AE-E 1 Lyman alpha irradiances are higher than the model calculations by between 40% and 80%. We suggest that the assumed calibration of the AE-E irradiances is in error

  20. Oxyanion flux characterization using passive flux meters: Development and field testing of surfactant-modified granular activated carbon

    Science.gov (United States)

    Lee, Jimi; Rao, P. S. C.; Poyer, Irene C.; Toole, Robyn M.; Annable, M. D.; Hatfield, K.

    2007-07-01

    We report here on the extension of Passive Flux Meter (PFM) applications for measuring fluxes of oxyanions in groundwater, and present results for laboratory and field studies. Granular activated carbon, with and without impregnated silver (GAC and SI-GAC, respectively), was modified with a cationic surfactant, hexadecyltrimethylammonium (HDTMA), to enhance the anion exchange capacity (AEC). Langmuir isotherm sorption maxima for oxyanions measured in batch experiments were in the following order: perchlorate >> chromate > selenate, consistent with their selectivity. Linear sorption isotherms for several alcohols suggest that surfactant modification of GAC and SI-GAC reduced (˜ 30-45%) sorption of alcohols by GAC. Water and oxyanion fluxes (perchlorate and chromate) measured by deploying PFMs packed with surfactant-modified GAC (SM-GAC) or surfactant-modified, silver-impregnated GAC (SM-SI-GAC) in laboratory flow chambers were in close agreement with the imposed fluxes. The use of SM-SI-GAC as a PFM sorbent was evaluated at a field site with perchlorate contamination of a shallow unconfined aquifer. PFMs packed with SM-SI-GAC were deployed in three existing monitoring wells with a perchlorate concentration range of ˜ 2.5 to 190 mg/L. PFM-measured, depth-averaged, groundwater fluxes ranged from 1.8 to 7.6 cm/day, while depth-averaged perchlorate fluxes varied from 0.22 to 1.7 g/m 2/day. Groundwater and perchlorate flux distributions measured in two PFM deployments closely matched each other. Depth-averaged Darcy fluxes measured with PFMs were in line with an estimate from a borehole dilution test, but much smaller than those based on hydraulic conductivity and head gradients; this is likely due to flow divergence caused by well-screen clogging. Flux-averaged perchlorate concentrations measured with PFM deployments matched concentrations in groundwater samples taken from one well, but not in two other wells, pointing to the need for additional field testing. Use of

  1. Collective motion of active Brownian particles with polar alignment.

    Science.gov (United States)

    Martín-Gómez, Aitor; Levis, Demian; Díaz-Guilera, Albert; Pagonabarraga, Ignacio

    2018-04-04

    We present a comprehensive computational study of the collective behavior emerging from the competition between self-propulsion, excluded volume interactions and velocity-alignment in a two-dimensional model of active particles. We consider an extension of the active brownian particles model where the self-propulsion direction of the particles aligns with the one of their neighbors. We analyze the onset of collective motion (flocking) in a low-density regime (10% surface area) and show that it is mainly controlled by the strength of velocity-alignment interactions: the competition between self-propulsion and crowding effects plays a minor role in the emergence of flocking. However, above the flocking threshold, the system presents a richer pattern formation scenario than analogous models without alignment interactions (active brownian particles) or excluded volume effects (Vicsek-like models). Depending on the parameter regime, the structure of the system is characterized by either a broad distribution of finite-sized polar clusters or the presence of an amorphous, highly fluctuating, large-scale traveling structure which can take a lane-like or band-like form (and usually a hybrid structure which is halfway in between both). We establish a phase diagram that summarizes collective behavior of polar active brownian particles and propose a generic mechanism to describe the complexity of the large-scale structures observed in systems of repulsive self-propelled particles.

  2. Primary visual cortex activity along the apparent-motion trace reflects illusory perception.

    Directory of Open Access Journals (Sweden)

    Lars Muckli

    2005-08-01

    Full Text Available The illusion of apparent motion can be induced when visual stimuli are successively presented at different locations. It has been shown in previous studies that motion-sensitive regions in extrastriate cortex are relevant for the processing of apparent motion, but it is unclear whether primary visual cortex (V1 is also involved in the representation of the illusory motion path. We investigated, in human subjects, apparent-motion-related activity in patches of V1 representing locations along the path of illusory stimulus motion using functional magnetic resonance imaging. Here we show that apparent motion caused a blood-oxygenation-level-dependent response along the V1 representations of the apparent-motion path, including regions that were not directly activated by the apparent-motion-inducing stimuli. This response was unaltered when participants had to perform an attention-demanding task that diverted their attention away from the stimulus. With a bistable motion quartet, we confirmed that the activity was related to the conscious perception of movement. Our data suggest that V1 is part of the network that represents the illusory path of apparent motion. The activation in V1 can be explained either by lateral interactions within V1 or by feedback mechanisms from higher visual areas, especially the motion-sensitive human MT/V5 complex.

  3. AmeriFlux Network Data Activities: updates, progress and plans

    Science.gov (United States)

    Yang, B.; Boden, T.; Krassovski, M.; Song, X.

    2013-12-01

    The Carbon Dioxide Information Analysis Center (CDIAC) at the Oak Ridge National Laboratory serves as the long-term data repository for the AmeriFlux network. Datasets currently available include hourly or half-hourly meteorological and flux observations, biological measurement records, and synthesis data products. In this presentation, we provide an update of this network database including a comprehensive review and evaluation of the biological data from about 70 sites, development of a new product for flux uncertainty estimates, and re-formatting of Level-2 standard files. In 2013, we also provided data support to two synthesis studies --- 2012 drought synthesis and FACE synthesis. Issues related to data quality and solutions in compiling datasets for these synthesis studies will be discussed. We will also present our work plans in developing and producing other high-level products, such as derivation of phenology from the available measurements at flux sites.

  4. Does historical wildfire activity alter metal fluxes to northern lakes?

    Science.gov (United States)

    Pelletier, N.; Chetelat, J.; Vermaire, J. C.; Palmer, M.; Black, J.; Pellisey, J.; Tracz, B.; van der Wielen, S.

    2017-12-01

    Current drought conditions in northwestern Canada are conducive to more frequent and severe wildfires that may mobilize mercury and other metals accumulated in soil and biomass. There is evidence that wildfires can remobilize and transport mercury within and outside catchments by atmospheric volatilization, particulate emissions and catchment soil erosion. However, the effect of fires on mercury fluxes to nearby lake sediments remains unclear. In this study, we use a combination of 10 dated lake sediment cores and four nearby ombrotrophic peatland cores to investigate the effects of wildfires on mercury fluxes to lake sediments. Lakes varying in catchment size and distance from recent fire events were sampled. Mercury concentrations in the environmental archives were measured, and macroscopic charcoal particles (>100 um) were counted at high resolution in the sediments to observe the co-variation of the local fire history and mercury fluxes. Mercury flux recorded in ombrotrophic peat cores provided an estimate of the historical atmospheric mercury flux from local and regional atmospheric deposition. The mercury flux recorded in lake sediments corresponds to the sum of direct atmospheric deposition and catchment transport. In combination, these archives will allow for the partitioning of mercury loading attributable to catchment transport from direct atmospheric deposition. After correcting the fluxes for particle focusing and terragenic elements input, flux from different lakes will be compared based on their catchment size and their temporal and spatial proximity known fire events. Altogether, our preliminary results using these paleolimnological methods will provide new insights on mercury transport processes that are predicted to become more important under a changing climate.

  5. Rough terrain motion planning for actively reconfigurable mobile robots

    Energy Technology Data Exchange (ETDEWEB)

    Brunner, Michael

    2015-02-05

    In the aftermath of the Tohoku earthquake and the nuclear meltdown at the power plant of Fukushima Daiichi in 2011, reconfigurable robots like the iRobot Packbot were deployed. Instead of humans, the robots were used to investigate contaminated areas. Other incidents are the two major earthquakes in Northern Italy in May 2012. Besides many casualties, a large number of historical buildings was severely damaged. Due to the imminent danger of collapse, it was too dangerous for rescue personnel to enter many of the buildings. Therefore, the sites were inspected by reconfigurable robots, which are able to traverse the rubble and debris of the partially destroyed buildings. This thesis develops a navigation system enabling wheeled and tracked robots to safely traverse rough terrain and challenging structures. It consists of a planning mechanism and a controller. The focus of this thesis, however, is on the contribution to motion planning. The planning scheme employs a hierarchical approach to motion planning for actively reconfigurable robots in rough environments. Using a map of the environment the algorithm estimates the traversability under the consideration of uncertainties. Based on this analysis, an initial path search determines an approximate solution with respect to the robot's operating limits.Subsequently, a detailed planning step refines the initial path where it is required. The refinement step considers the robot's actuators and stability in addition to the quantities of the first search. Determining the robot-terrain interaction is very important in rough terrain. This thesis presents two path refinement approaches: a deterministic and a randomized approach. The experimental evaluation investigates the separate components of the planning scheme, the robot-terrain interaction for instance.In simulation as well as in real world experiments the evaluation demonstrates the necessity of such a planning algorithm in rough terrain and it provides

  6. Rough terrain motion planning for actively reconfigurable mobile robots

    International Nuclear Information System (INIS)

    Brunner, Michael

    2015-01-01

    In the aftermath of the Tohoku earthquake and the nuclear meltdown at the power plant of Fukushima Daiichi in 2011, reconfigurable robots like the iRobot Packbot were deployed. Instead of humans, the robots were used to investigate contaminated areas. Other incidents are the two major earthquakes in Northern Italy in May 2012. Besides many casualties, a large number of historical buildings was severely damaged. Due to the imminent danger of collapse, it was too dangerous for rescue personnel to enter many of the buildings. Therefore, the sites were inspected by reconfigurable robots, which are able to traverse the rubble and debris of the partially destroyed buildings. This thesis develops a navigation system enabling wheeled and tracked robots to safely traverse rough terrain and challenging structures. It consists of a planning mechanism and a controller. The focus of this thesis, however, is on the contribution to motion planning. The planning scheme employs a hierarchical approach to motion planning for actively reconfigurable robots in rough environments. Using a map of the environment the algorithm estimates the traversability under the consideration of uncertainties. Based on this analysis, an initial path search determines an approximate solution with respect to the robot's operating limits.Subsequently, a detailed planning step refines the initial path where it is required. The refinement step considers the robot's actuators and stability in addition to the quantities of the first search. Determining the robot-terrain interaction is very important in rough terrain. This thesis presents two path refinement approaches: a deterministic and a randomized approach. The experimental evaluation investigates the separate components of the planning scheme, the robot-terrain interaction for instance.In simulation as well as in real world experiments the evaluation demonstrates the necessity of such a planning algorithm in rough terrain and it provides

  7. Formation of a double-decker magnetic flux rope in the sigmoidal solar active region 11520

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, X.; Ding, M. D.; Zhang, J.; Guo, Y. [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China); Sun, X. D. [W. W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305 (United States); Wang, Y. M. [School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026 (China); Kliem, B. [Institute of Physics and Astronomy, University of Potsdam, D-14476 Potsdam (Germany); Deng, Y. Y., E-mail: xincheng@nju.edu.cn [Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

    2014-07-10

    In this paper, we address the formation of a magnetic flux rope (MFR) that erupted on 2012 July 12 and caused a strong geomagnetic storm event on July 15. Through analyzing the long-term evolution of the associated active region observed by the Atmospheric Imaging Assembly and the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory, it is found that the twisted field of an MFR, indicated by a continuous S-shaped sigmoid, is built up from two groups of sheared arcades near the main polarity inversion line a half day before the eruption. The temperature within the twisted field and sheared arcades is higher than that of the ambient volume, suggesting that magnetic reconnection most likely works there. The driver behind the reconnection is attributed to shearing and converging motions at magnetic footpoints with velocities in the range of 0.1-0.6 km s{sup –1}. The rotation of the preceding sunspot also contributes to the MFR buildup. Extrapolated three-dimensional non-linear force-free field structures further reveal the locations of the reconnection to be in a bald-patch region and in a hyperbolic flux tube. About 2 hr before the eruption, indications of a second MFR in the form of an S-shaped hot channel are seen. It lies above the original MFR that continuously exists and includes a filament. The whole structure thus makes up a stable double-decker MFR system for hours prior to the eruption. Eventually, after entering the domain of instability, the high-lying MFR impulsively erupts to generate a fast coronal mass ejection and X-class flare; while the low-lying MFR remains behind and continuously maintains the sigmoidicity of the active region.

  8. Formation of a double-decker magnetic flux rope in the sigmoidal solar active region 11520

    International Nuclear Information System (INIS)

    Cheng, X.; Ding, M. D.; Zhang, J.; Guo, Y.; Sun, X. D.; Wang, Y. M.; Kliem, B.; Deng, Y. Y.

    2014-01-01

    In this paper, we address the formation of a magnetic flux rope (MFR) that erupted on 2012 July 12 and caused a strong geomagnetic storm event on July 15. Through analyzing the long-term evolution of the associated active region observed by the Atmospheric Imaging Assembly and the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory, it is found that the twisted field of an MFR, indicated by a continuous S-shaped sigmoid, is built up from two groups of sheared arcades near the main polarity inversion line a half day before the eruption. The temperature within the twisted field and sheared arcades is higher than that of the ambient volume, suggesting that magnetic reconnection most likely works there. The driver behind the reconnection is attributed to shearing and converging motions at magnetic footpoints with velocities in the range of 0.1-0.6 km s –1 . The rotation of the preceding sunspot also contributes to the MFR buildup. Extrapolated three-dimensional non-linear force-free field structures further reveal the locations of the reconnection to be in a bald-patch region and in a hyperbolic flux tube. About 2 hr before the eruption, indications of a second MFR in the form of an S-shaped hot channel are seen. It lies above the original MFR that continuously exists and includes a filament. The whole structure thus makes up a stable double-decker MFR system for hours prior to the eruption. Eventually, after entering the domain of instability, the high-lying MFR impulsively erupts to generate a fast coronal mass ejection and X-class flare; while the low-lying MFR remains behind and continuously maintains the sigmoidicity of the active region.

  9. Activity-based exploitation of Full Motion Video (FMV)

    Science.gov (United States)

    Kant, Shashi

    2012-06-01

    Video has been a game-changer in how US forces are able to find, track and defeat its adversaries. With millions of minutes of video being generated from an increasing number of sensor platforms, the DOD has stated that the rapid increase in video is overwhelming their analysts. The manpower required to view and garner useable information from the flood of video is unaffordable, especially in light of current fiscal restraints. "Search" within full-motion video has traditionally relied on human tagging of content, and video metadata, to provision filtering and locate segments of interest, in the context of analyst query. Our approach utilizes a novel machine-vision based approach to index FMV, using object recognition & tracking, events and activities detection. This approach enables FMV exploitation in real-time, as well as a forensic look-back within archives. This approach can help get the most information out of video sensor collection, help focus the attention of overburdened analysts form connections in activity over time and conserve national fiscal resources in exploiting FMV.

  10. Ambulatory measurement of knee motion and physical activity: preliminary evaluation of a smart activity monitor

    Directory of Open Access Journals (Sweden)

    Malchau Henrik

    2006-09-01

    Full Text Available Abstract Background There is currently a paucity of devices available for continuous, long-term monitoring of human joint motion. Non-invasive, inexpensive devices capable of recording human activity and joint motion have many applications for medical research. Such a device could be used to quantify range of motion outside the gait laboratory. The purpose of this study was to test the accuracy of the modified Intelligent Device for Energy Expenditure and Activity (IDEEA in measuring knee flexion angles, to detect different physical activities, and to quantify how often healthy subjects use deep knee flexion in the ambulatory setting. Methods We compared Biomotion Laboratory (BML "gold standard" data to simultaneous IDEEA measures of knee motion and gait, step up/down, and stair descent in 5 healthy subjects. In addition, we used a series of choreographed physical activities outside the BML to confirm the IDEEA's ability to accurately measure 7 commonly-performed physical activities. Subjects then continued data collection during ordinary activities outside the gait laboratory. Results Pooled correlations between the BML and IDEEA knee flexion angles were .97 +/- .03 for step up/down, .98 +/- .02 for stair descent, and .98 +/- .01 for gait. In the BML protocol, the IDEEA accurately identified gait, but was less accurate in identifying step up/down and stair descent. During sampling outside the BML, the IDEEA accurately detected walking, running, stair ascent, stair descent, standing, lying, and sitting. On average, subjects flexed their knees >120° for 0.17% of their data collection periods outside the BML. Conclusion The modified IDEEA system is a useful clinical tool for evaluating knee motion and multiple physical activities in the ambulatory setting. These five healthy subjects rarely flexed their knees >120°.

  11. Magnetic flux motion in (PrxY1−xBa2Cu3O7−δ polycrystal samples sintered in Ar and O2 atmospheres

    Directory of Open Access Journals (Sweden)

    S. Favre

    2016-09-01

    Full Text Available We present a comparative study of the magnetic flux motion in ceramic pellets made of (PrxY1−xBa2Cu3O7−δ as a function of their composition and morphology. Samples produced in Ar or O2 atmosphere present noticeable differences in their magnetic response that we explain in terms of their structural parameters. The material’s parameters that most influence the flux dynamics are morphology and oxygen content, that change dramatically with the sintering atmosphere. Moderate changes are also observed as a function of the Pr content. Magnetic pinning efficiency is discussed in terms of intergranular couplings and effective activation energies, estimated from AC-susceptibility and magnetoresistance measurements.

  12. Reduced flux motion via flux creep annealing in high- Jc single-crystal Y1Ba2Cu3O7

    International Nuclear Information System (INIS)

    Thompson, J.R.; Sun, Y.R.; Malozemoff, A.P.; Christen, D.K.; Kerchner, H.R.; Ossandon, J.G.; Marwick, A.D.; Holtzberg, F.

    1991-01-01

    We investigated the stabilization of magnetic flux in a high-temperature superconductor (a proton-irradiated Y 1 Ba 2 Cu 3 O 7 crystal), by operating with subcritical current density J. Using the thermal history to obtain an induced current density J≤J c , we observed a drastically reduced relaxation rate dM/dt (M=magnetization), after ''flux creep annealing.'' The results show that the field gradient ∼J∼M determined the relaxation rate, independent of the sample's H-T history, in agreement with recent theory

  13. Very low speed performance of active flux based sensorless control: interior permanent magnet synchronous motor vector control versus direct torque and flux control

    DEFF Research Database (Denmark)

    Paicu, M. C.; Boldea, I.; Andreescu, G. D.

    2009-01-01

    This study is focused on very low speed performance comparison between two sensorless control systems based on the novel ‘active flux' concept, that is, the current/voltage vector control versus direct torque and flux control (DTFC) for interior permanent magnet synchronous motor (IPMSM) drives...... with space vector modulation (SVM), without signal injection. The active flux, defined as the flux that multiplies iq current in the dq-model torque expression of all ac machines, is easily obtained from the stator-flux vector and has the rotor position orientation. Therefore notable simplification...

  14. Comparison of flux motion in type-II superconductors including pinning centers with the shapes of nano-rods and nano-particles by using 3D-TDGL simulation

    International Nuclear Information System (INIS)

    Ito, Shintaro; Ichino, Yusuke; Yoshida, Yutaka

    2015-01-01

    Highlights: • We constructed the 3D-TDGL simulator to calculate the flux motion. • We assumed two superconductors including only nano-rods and only nano-particles. • We succeeded to simulate the flux motion for various magnetic field angles. • If anyone introduce nano-rod, controlling the “single-kink” motion is very important. • The introduction of nano-particles is effective to pin the “single-kink” motion. - Abstract: Time-dependent Ginzburg–Landau (TDGL) equations are very useful method for simulation of the motion of flux quanta in type-II superconductors. We constructed the 3D-TDGL simulator and succeeded to simulate the motion of flux quanta in 3-dimension. We carried out the 3D-TDGL simulation to compare two superconductors which included only pinning centers with the shape of nano-rods and only nano-particle-like pinning centers in the viewpoint of the flux motion. As a result, a motion of “single-kink” caused the whole motion of a flux quantum in the superconductor including only the nano-rods. On the other hand, in the superconductor including the nano-particles, the flux quanta were pinned by the nano-particles in the various magnetic field applied angles. As the result, no “single-kink” occurred in the superconductor including the nano-particles. Therefore, the nano-particle-like pinning centers are effective shape to trap flux quanta for various magnetic field applied angles.

  15. Implied motion because of instability in Hokusai Manga activates the human motion-sensitive extrastriate visual cortex: an fMRI study of the impact of visual art.

    Science.gov (United States)

    Osaka, Naoyuki; Matsuyoshi, Daisuke; Ikeda, Takashi; Osaka, Mariko

    2010-03-10

    The recent development of cognitive neuroscience has invited inference about the neurosensory events underlying the experience of visual arts involving implied motion. We report functional magnetic resonance imaging study demonstrating activation of the human extrastriate motion-sensitive cortex by static images showing implied motion because of instability. We used static line-drawing cartoons of humans by Hokusai Katsushika (called 'Hokusai Manga'), an outstanding Japanese cartoonist as well as famous Ukiyoe artist. We found 'Hokusai Manga' with implied motion by depicting human bodies that are engaged in challenging tonic posture significantly activated the motion-sensitive visual cortex including MT+ in the human extrastriate cortex, while an illustration that does not imply motion, for either humans or objects, did not activate these areas under the same tasks. We conclude that motion-sensitive extrastriate cortex would be a critical region for perception of implied motion in instability.

  16. Active control of divertor heat and particle fluxes in EAST towards advanced steady state operations

    Energy Technology Data Exchange (ETDEWEB)

    Wang, L., E-mail: lwang@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Dalian University of Technology, Dalian 116024 (China); Guo, H.Y. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); General Atomics, P. O. Box 85608, San Diego, CA 92186 (United States); Li, J.; Wan, B.N.; Gong, X.Z.; Zhang, X.D.; Hu, J.S. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Liang, Y. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Association EURATOM-FZJ, D-52425 Jülich (Germany); Xu, G.S. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Zou, X.L. [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Loarte, A. [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul Lez Durance (France); Maingi, R.; Menard, J.E. [Princeton Plasma Physics Laboratory, Princeton, NJ 08543 (United States); Luo, G.N.; Gao, X.; Hu, L.Q.; Gan, K.F.; Liu, S.C.; Wang, H.Q.; Chen, R. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); and others

    2015-08-15

    Significant progress has been made in EAST towards advanced steady state operations by active control of divertor heat and particle fluxes. Many innovative techniques have been developed to mitigate transient ELM and stationary heat fluxes on the divertor target plates. It has been found that lower hybrid current drive (LHCD) can lead to edge plasma ergodization, striation of the stationary heat flux and lower ELM transient heat and particle fluxes. With multi-pulse supersonic molecular beam injection (SMBI) to quantitatively regulate the divertor particle flux, the divertor power footprint pattern can be actively modified. H-modes have been extended over 30 s in EAST with the divertor peak heat flux and the target temperature being controlled well below 2 MW/m{sup 2} and 250 °C, respectively, by integrating these new methods, coupled with advanced lithium wall conditioning and internal divertor pumping, along with an edge coherent mode to provide continuous particle and power exhaust.

  17. A triboelectric motion sensor in wearable body sensor network for human activity recognition.

    Science.gov (United States)

    Hui Huang; Xian Li; Ye Sun

    2016-08-01

    The goal of this study is to design a novel triboelectric motion sensor in wearable body sensor network for human activity recognition. Physical activity recognition is widely used in well-being management, medical diagnosis and rehabilitation. Other than traditional accelerometers, we design a novel wearable sensor system based on triboelectrification. The triboelectric motion sensor can be easily attached to human body and collect motion signals caused by physical activities. The experiments are conducted to collect five common activity data: sitting and standing, walking, climbing upstairs, downstairs, and running. The k-Nearest Neighbor (kNN) clustering algorithm is adopted to recognize these activities and validate the feasibility of this new approach. The results show that our system can perform physical activity recognition with a successful rate over 80% for walking, sitting and standing. The triboelectric structure can also be used as an energy harvester for motion harvesting due to its high output voltage in random low-frequency motion.

  18. STUDY OF THE POYNTING FLUX IN ACTIVE REGION 10930 USING DATA-DRIVEN MAGNETOHYDRODYNAMIC SIMULATION

    International Nuclear Information System (INIS)

    Fan, Y. L.; Wang, H. N.; He, H.; Zhu, X. S.

    2011-01-01

    Powerful solar flares are closely related to the evolution of magnetic field configuration on the photosphere. We choose the Poynting flux as a parameter in the study of magnetic field changes. We use time-dependent multidimensional MHD simulations around a flare occurrence to generate the results, with the temporal variation of the bottom boundary conditions being deduced from the projected normal characteristic method. By this method, the photospheric magnetogram could be incorporated self-consistently as the bottom condition of data-driven simulations. The model is first applied to a simulation datum produced by an emerging magnetic flux rope as a test case. Then, the model is used to study NOAA AR 10930, which has an X3.4 flare, the data of which has been obtained by the Hinode/Solar Optical Telescope on 2006 December 13. We compute the magnitude of Poynting flux (S total ), radial Poynting flux (S z ), a proxy for ideal radial Poynting flux (S proxy ), Poynting flux due to plasma surface motion (S sur ), and Poynting flux due to plasma emergence (S emg ) and analyze their extensive properties in four selected areas: the whole sunspot, the positive sunspot, the negative sunspot, and the strong-field polarity inversion line (SPIL) area. It is found that (1) the S total , S z , and S proxy parameters show similar behaviors in the whole sunspot area and in the negative sunspot area. The evolutions of these three parameters in the positive area and the SPIL area are more volatile because of the effect of sunspot rotation and flux emergence. (2) The evolution of S sur is largely influenced by the process of sunspot rotation, especially in the positive sunspot. The evolution of S emg is greatly affected by flux emergence, especially in the SPIL area.

  19. A low-frequency wave motion mechanism enables efficient energy transport in carbon nanotubes at high heat fluxes.

    Science.gov (United States)

    Zhang, Xiaoliang; Hu, Ming; Poulikakos, Dimos

    2012-07-11

    The great majority of investigations of thermal transport in carbon nanotubes (CNTs) in the open literature focus on low heat fluxes, that is, in the regime of validity of the Fourier heat conduction law. In this paper, by performing nonequilibrium molecular dynamics simulations we investigated thermal transport in a single-walled CNT bridging two Si slabs under constant high heat flux. An anomalous wave-like kinetic energy profile was observed, and a previously unexplored, wave-dominated energy transport mechanism is identified for high heat fluxes in CNTs, originated from excited low frequency transverse acoustic waves. The transported energy, in terms of a one-dimensional low frequency mechanical wave, is quantified as a function of the total heat flux applied and is compared to the energy transported by traditional Fourier heat conduction. The results show that the low frequency wave actually overtakes traditional Fourier heat conduction and efficiently transports the energy at high heat flux. Our findings reveal an important new mechanism for high heat flux energy transport in low-dimensional nanostructures, such as one-dimensional (1-D) nanotubes and nanowires, which could be very relevant to high heat flux dissipation such as in micro/nanoelectronics applications.

  20. A Trap Motion in Validating Muscle Activity Prediction from Musculoskeletal Model using EMG

    NARCIS (Netherlands)

    Wibawa, A. D.; Verdonschot, N.; Halbertsma, J.P.K.; Burgerhof, J.G.M.; Diercks, R.L.; Verkerke, G. J.

    2016-01-01

    Musculoskeletal modeling nowadays is becoming the most common tool for studying and analyzing human motion. Besides its potential in predicting muscle activity and muscle force during active motion, musculoskeletal modeling can also calculate many important kinetic data that are difficult to measure

  1. A Comparison of the Performance Improvement by Collocated and Noncollocated Active Damping in Motion Systems

    NARCIS (Netherlands)

    Babakhani, B.; de Vries, Theodorus J.A.; van Amerongen, J.

    2012-01-01

    In this paper, both collocated and noncollocated active vibration control (AVC) of a the vibrations in a motion system are considered. Pole-zero plots of both the AVC loop and the motion-control (MC) loop are used to analyze the effect of the applied active damping on the system dynamics. Using

  2. Application of inertial sensors and flux-gate magnetometer to real-time human body motion capture

    OpenAIRE

    Frey, William.

    1996-01-01

    Human body tracking for synthetic environment interface has become a significant human- computer interface challenge. There are several different types of motion capture systems currently available. Inherent problems, most resulting from the use of artificially-generated source signals, plague these systems. A proposed motion capture system is being developed at the Naval Postgraduate School which utilizes a combination of inertial sensors to overcome these difficulties. However, the current ...

  3. Thermally activated dislocation motion including inertial effects in solid solutions

    International Nuclear Information System (INIS)

    Isaac, R.D.

    1977-01-01

    Dislocation motion through an array of obstacles is considered in terms of the potential energy of the dislocation as it moves through the array. The obstacles form a series of potential wells and barriers which can trap the dislocations. The effect of thermal fluctuations and of a viscous drag on the motion of the dislocation is investigated by analogy with Brownian motion in a field of force. The rate of escape of a trapped dislocation is found to depend on the damping coefficient only for a large viscous drag. The probability that a dislocation will be trapped by a well or barrier is found to depend on the damping coefficient for a small viscous drag. This inertial effect determines how far a dislocation will travel after breaking away from an obstacle

  4. Bayesian calibration of reactor neutron flux spectrum using activation detectors measurements: Application to CALIBAN reactor

    Energy Technology Data Exchange (ETDEWEB)

    Cartier, J. [Commissariat a l' Energie Atomique et aux Energies Alternatives CEA, DAM, DIF, F-91297 Arpajon (France); Casoli, P. [Commissariat a l' Energie Atomique et aux Energies Alternatives CEA, DAM, Valduc, F-21120 Is sur Tille (France); Chappert, F. [Commissariat a l' Energie Atomique et aux Energies Alternatives CEA, DAM, DIF, F-91297 Arpajon (France)

    2013-07-01

    In this paper, we present calibration methods in order to estimate reactor neutron flux spectrum and its uncertainties by using integral activation measurements. These techniques are performed using Bayesian and MCMC framework. These methods are applied to integral activation experiments in the cavity of the CALIBAN reactor. We estimate the neutron flux and its related uncertainties. The originality of this work is that these uncertainties take into account measurements uncertainties, cross-sections uncertainties and model error. In particular, our results give a very good approximation of the total flux and indicate that neutron flux from MCNP simulation for energies above about 5 MeV seems to overestimate the 'real flux'. (authors)

  5. The general setting for the zero-flux condition: The lagrangian and zero-flux conditions that give the heisenberg equation of motion.

    Science.gov (United States)

    Anderson, James S M; Ayers, Paul W

    2018-06-30

    Generalizing our recent work on relativistic generalizations of the quantum theory of atoms in molecules, we present the general setting under which the principle of stationary action for a region leads to open quantum subsystems. The approach presented here is general and works for any Hamiltonian, and when a reasonable Lagrangian is selected, it often leads to the integral of the Laplacian of the electron density on the region vanishing as a necessary condition for the zero-flux surface. Alternatively, with this method, one can design a Lagrangian that leads to a surface of interest (though this Lagrangian may not be, and indeed probably will not be, "reasonable"). For any reasonable Lagrangian for the electronic wave function and any two-component method (related by integration by parts to the Hamiltonian) considered, the Bader definition of an atom is recaptured. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

  6. Thermal, intermediate and fast neutron flux measurements using activation detectors; Mesure des flux de neutrons thermiques, intermediaires et rapides au moyen de detecteurs par activation

    Energy Technology Data Exchange (ETDEWEB)

    Brisbois, J; Lott, M; Manent, G [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1964-07-01

    The problem of neutron flux measurements using activation detectors is studied in the particular case of protection research. It is shown how it possible, it is possible, using a known thermal flux, to organise a coherent calibration system for all the detectors. The rapid neutron detectors are calibrated with respect to a reference detector (phosphorus) in a natural uranium converter; the intermediate neutron detectors with respect to gold in the axial channel of ZOE. This method makes it possible to minimise the errors due to the activation cross-sections. A brief description is given of the counting room of the Pile Safety Study Service, as well of the practical utilisation characteristics of the counters employed. (authors) [French] Le probleme de la mesure des flux de neutrons au moyen de detecteurs par activation est etudie dans le cas particulier des etudes de protections. On montre comment, a partir d'un flux thermique connu, on peut organiser un systeme coherent d'etalonnage de tous les detecteurs. Les detecteurs de neutrons rapides sont etalonnes par rapport a un detecteur de reference (phosphore) dans un convertisseur en uranium naturel; les detecteurs de neutrons intermediaires, par rapport a l'or dans le canal axial de ZOE, Cette methode permet de minimiser les erreurs dues aux sections efficaces d'activation. On decrit sommairement la salle de comptage du Service d'Etudes de Protections de Piles et on indique les caracteristiques d'emploi pratique des detecteurs utilises. (auteurs)

  7. MAGNETIC FLUX TRANSPORT AND THE LONG-TERM EVOLUTION OF SOLAR ACTIVE REGIONS

    International Nuclear Information System (INIS)

    Ugarte-Urra, Ignacio; Upton, Lisa; Warren, Harry P.; Hathaway, David H.

    2015-01-01

    With multiple vantage points around the Sun, Solar Terrestrial Relations Observatory (STEREO) and Solar Dynamics Observatory imaging observations provide a unique opportunity to view the solar surface continuously. We use He ii 304 Å data from these observatories to isolate and track ten active regions and study their long-term evolution. We find that active regions typically follow a standard pattern of emergence over several days followed by a slower decay that is proportional in time to the peak intensity in the region. Since STEREO does not make direct observations of the magnetic field, we employ a flux-luminosity relationship to infer the total unsigned magnetic flux evolution. To investigate this magnetic flux decay over several rotations we use a surface flux transport model, the Advective Flux Transport model, that simulates convective flows using a time-varying velocity field and find that the model provides realistic predictions when information about the active region's magnetic field strength and distribution at peak flux is available. Finally, we illustrate how 304 Å images can be used as a proxy for magnetic flux measurements when magnetic field data is not accessible

  8. Short communication: Assessment of activity patterns of growing rabbits in a flux-controlled chamber

    Directory of Open Access Journals (Sweden)

    Irene Olivas

    2013-06-01

    Full Text Available Flux-controlled and metabolic chambers are often used for nutritional and environmental studies. However, the potential alterations of animal behaviour and welfare are so far not fully understood. In consequence, this study had 2 main objectives: to assess potential alterations of animal activity pattern and time budget inside a flux chamber, and to assess the importance of the “rearing up” behaviour. To this end, 10 growing rabbits of different ages (from 1 to 5 wk of the growing period were housed inside a flux chamber. Their activity was continuously recorded and assessed, determining the frequency and duration of 8 different behaviours: lying, sleeping, sitting, eating, drinking, walking, rearing up and others. Nocturnal rabbit behaviour and time budget were not altered inside the chamber if compared to previously described rabbit activity under conventional cages. In addition, rabbits in this experiment presented a tendency to perform “rearing up” when housed inside the flux chamber.

  9. Localized, Non-Harmonic Active Flap Motions for Low Frequency In-Plane Rotor Noise Reduction

    Science.gov (United States)

    Sim, Ben W.; Potsdam, Mark; Kitaplioglu, Cahit; LeMasurier, Philip; Lorber, Peter; Andrews, Joseph

    2012-01-01

    A first-of-its-kind demonstration of the use of localized, non-harmonic active flap motions, for suppressing low frequency, in-plane rotor noise, is reported in this paper. Operational feasibility is verified via testing of the full-scale AATD/Sikorsky/UTRC active flap demonstration rotor in the NFAC's 40- by 80-Foot anechoic wind tunnel. Effectiveness of using localized, non-harmonic active flap motions are compared to conventional four-per-rev harmonic flap motions, and also active flap motions derived from closed-loop acoustics implementations. All three approaches resulted in approximately the same noise reductions over an in-plane three-by-three microphone array installed forward and near in-plane of the rotor in the nearfield. It is also reported that using an active flap in this localized, non-harmonic manner, resulted in no more that 2% rotor performance penalty, but had the tendency to incur higher hub vibration levels.

  10. Motion direction estimation based on active RFID with changing environment

    Science.gov (United States)

    Jie, Wu; Minghua, Zhu; Wei, He

    2018-05-01

    The gate system is used to estimate the direction of RFID tags carriers when they are going through the gate. Normally, it is difficult to achieve and keep a high accuracy in estimating motion direction of RFID tags because the received signal strength of tag changes sharply according to the changing electromagnetic environment. In this paper, a method of motion direction estimation for RFID tags is presented. To improve estimation accuracy, the machine leaning algorithm is used to get the fitting function of the received data by readers which are deployed inside and outside gate respectively. Then the fitted data are sampled to get the standard vector. We compare the stand vector with template vectors to get the motion direction estimation result. Then the corresponding template vector is updated according to the surrounding environment. We conducted the simulation and implement of the proposed method and the result shows that the proposed method in this work can improve and keep a high accuracy under the condition of the constantly changing environment.

  11. Integrated thermal infrared imaging and Structure-from-Motion photogrametry to map apparent temperature and radiant hydrothermal heat flux at Mammoth Mountain, CA USA

    Science.gov (United States)

    Lewis, Aaron; George Hilley,; Lewicki, Jennifer L.

    2015-01-01

    This work presents a method to create high-resolution (cm-scale) orthorectified and georeferenced maps of apparent surface temperature and radiant hydrothermal heat flux and estimate the radiant hydrothermal heat emission rate from a study area. A ground-based thermal infrared (TIR) camera was used to collect (1) a set of overlapping and offset visible imagery around the study area during the daytime and (2) time series of co-located visible and TIR imagery at one or more sites within the study area from pre-dawn to daytime. Daytime visible imagery was processed using the Structure-from-Motion photogrammetric method to create a digital elevation model onto which pre-dawn TIR imagery was orthorectified and georeferenced. Three-dimensional maps of apparent surface temperature and radiant hydrothermal heat flux were then visualized and analyzed from various computer platforms (e.g., Google Earth, ArcGIS). We demonstrate this method at the Mammoth Mountain fumarole area on Mammoth Mountain, CA. Time-averaged apparent surface temperatures and radiant hydrothermal heat fluxes were observed up to 73.7 oC and 450 W m-2, respectively, while the estimated radiant hydrothermal heat emission rate from the area was 1.54 kW. Results should provide a basis for monitoring potential volcanic unrest and mitigating hydrothermal heat-related hazards on the volcano.

  12. Bayesian statistics applied to neutron activation data for reactor flux spectrum analysis

    International Nuclear Information System (INIS)

    Chiesa, Davide; Previtali, Ezio; Sisti, Monica

    2014-01-01

    Highlights: • Bayesian statistics to analyze the neutron flux spectrum from activation data. • Rigorous statistical approach for accurate evaluation of the neutron flux groups. • Cross section and activation data uncertainties included for the problem solution. • Flexible methodology applied to analyze different nuclear reactor flux spectra. • The results are in good agreement with the MCNP simulations of neutron fluxes. - Abstract: In this paper, we present a statistical method, based on Bayesian statistics, to analyze the neutron flux spectrum from the activation data of different isotopes. The experimental data were acquired during a neutron activation experiment performed at the TRIGA Mark II reactor of Pavia University (Italy) in four irradiation positions characterized by different neutron spectra. In order to evaluate the neutron flux spectrum, subdivided in energy groups, a system of linear equations, containing the group effective cross sections and the activation rate data, has to be solved. However, since the system’s coefficients are experimental data affected by uncertainties, a rigorous statistical approach is fundamental for an accurate evaluation of the neutron flux groups. For this purpose, we applied the Bayesian statistical analysis, that allows to include the uncertainties of the coefficients and the a priori information about the neutron flux. A program for the analysis of Bayesian hierarchical models, based on Markov Chain Monte Carlo (MCMC) simulations, was used to define the problem statistical model and solve it. The first analysis involved the determination of the thermal, resonance-intermediate and fast flux components and the dependence of the results on the Prior distribution choice was investigated to confirm the reliability of the Bayesian analysis. After that, the main resonances of the activation cross sections were analyzed to implement multi-group models with finer energy subdivisions that would allow to determine the

  13. Filament Activation in Response to Magnetic Flux Emergence and Cancellation in Filament Channels

    Science.gov (United States)

    Li, Ting; Zhang, Jun; Ji, Haisheng

    2015-06-01

    We conducted a comparative analysis of two filaments that showed a quite different activation in response to the flux emergence within the filament channels. The observations from the Solar Dynamics Observatory (SDO) and Global Oscillation Network Group (GONG) were made to analyze the two filaments on 2013 August 17 - 20 (SOL2013-08-17) and September 29 (SOL2013-09-29). The first event showed that the main body of the filament was separated into two parts when an active region (AR) emerged with a maximum magnetic flux of about 6.4×1021 Mx underlying the filament. The close neighborhood and common direction of the bright threads in the filament and the open AR fan loops suggest a similar magnetic connectivity of these two flux systems. The equilibrium of the filament was not destroyed three days after the start of the emergence of the AR. To our knowledge, similar observations have never been reported before. In the second event, the emerging flux occurred nearby a barb of the filament with a maximum magnetic flux of 4.2×1020 Mx, about one order of magnitude lower than that of the first event. Two patches of parasitic polarity in the vicinity of the barb merged, then cancelled with nearby network fields. About 20 hours after the onset of the emergence, the filament erupted. Our findings imply that the location of emerging flux within the filament channel is probably crucial to filament evolution. If the flux emergence appears nearby the barbs, it is highly likely that the emerging flux and the filament magnetic fields will cancel, which may lead to the eruption of the filament. The comparison of the two events shows that the emergence of a small AR may still not be enough to disrupt the stability of a filament system, and the actual eruption only occurs after the flux cancellation sets in.

  14. Measurements of flux pumping activation of trapped field magnets

    Energy Technology Data Exchange (ETDEWEB)

    Weinstein, Roy; Parks, Drew; Sawh, Ravi-Persad [Texas Center for Superconductivity, 202 Houston Science Center, University of Houston, Houston, TX 77204-5002 (United States); Davey, Kent [Physics Department, 617 Science and Research Building I, University of Houston, Houston, TX 77204-5005 (United States)

    2010-11-15

    Large grains of high temperature superconducting (HTS) material can be utilized as trapped field magnets (TFMs). Persistent currents are set up in the HTS when it is cooled in a magnetic field, or exposed to a magnetic field after cooling. TFMs have been improved over the past two decades by the efforts of a large number of worldwide research groups. However, applications using TFMs have lagged, in part due to the problem of high fields needed for activation. We describe herein experiments designed to observe the behaviour of TFM activation using repeated applications of low fields (called 'pumping'). Significant partial activation is obtained using a non-uniform pumping field (e.g., a small permanent magnet) which is higher in the centre of the HTS than at the periphery. Cooling in zero field followed by pumping with such a field results in trapping the full applied field, in comparison to half of the applied field being trapped by cooling in zero field followed by application of a uniform field. We find that for partial activation by cooling in a field and subsequent activation by pumping, the resulting fields are additive. We also conclude that for activation by fluxoid pumping, creep assists the process.

  15. Sunspot proper motions in active region NOAA 2372 and its flare activity during SMY period of 1980 April 4-13

    International Nuclear Information System (INIS)

    Ambastha, A.; Bhatnagar, A.

    1988-01-01

    Solar Active Region NOAA 2372 was observed extensively by the Solar Maximum Mission (SMM) satellite and several ground-based observatories during 1980 April 4-13 in the Solar Maximum Year. After its birth around April 4, it underwent a rapid growth and produced a reported 84 flares in the course of its disc passage. In this paper, photospheric and chromospheric observations of this active region have been studied together with Marshall Space Flight Center magnetograms and X-ray data from HXIS aboard the SMM satellite. In particular, the relationship of the flare-productivity with sunspot proper motions and emergence of new regions of magnetic flux in the active region from its birth to its disappearance at the W-limb has been discussed. (author). 7 figures, 2 tables, 29 refs

  16. Active motions of Brownian particles in a generalized energy-depot model

    International Nuclear Information System (INIS)

    Zhang Yong; Koo Kim, Chul; Lee, Kong-Ju-Bock

    2008-01-01

    We present a generalized energy-depot model in which the rate of conversion of the internal energy into motion can be dependent on the position and velocity of a particle. When the conversion rate is a general function of the velocity, the active particle exhibits diverse patterns of motion, including a braking mechanism and a stepping motion. The phase trajectories of the motion are investigated in a systematic way. With a particular form of the conversion rate dependent on the position and velocity, the particle shows a spontaneous oscillation characterizing a negative stiffness. These types of active behaviors are compared with similar phenomena observed in biology, such as the stepping motion of molecular motors and amplification in the hearing mechanism. Hence, our model can provide a generic understanding of the active motion related to the energy conversion and also a new control mechanism for nano-robots. We also investigate the effect of noise, especially on the stepping motion, and observe random walk-like behavior as expected.

  17. Autophagic flux is highly active in early mitosis and differentially regulated throughout the cell cycle.

    Science.gov (United States)

    Li, Zhiyuan; Ji, Xinmiao; Wang, Dongmei; Liu, Juanjuan; Zhang, Xin

    2016-06-28

    Mitosis is a fast process that involves dramatic cellular remodeling and has a high energy demand. Whether autophagy is active or inactive during the early stages of mitosis in a naturally dividing cell is still debated. Here we aimed to use multiple assays to resolve this apparent discrepancy. Although the LC3 puncta number was reduced in mitosis, the four different cell lines we tested all have active autophagic flux in both interphase and mitosis. In addition, the autophagic flux was highly active in nocodazole-induced, double-thymidine synchronization released as well as naturally occurring mitosis in HeLa cells. Multiple autophagy proteins are upregulated in mitosis and the increased Beclin-1 level likely contributes to the active autophagic flux in early mitosis. It is interesting that although the autophagic flux is active throughout the cell cycle, early mitosis and S phase have relatively higher autophagic flux than G1 and late G2 phases, which might be helpful to degrade the damaged organelles and provide energy during S phase and mitosis.

  18. Studies on the weldability, microstructure and mechanical properties of activated flux TIG weldments of Inconel 718

    International Nuclear Information System (INIS)

    Ramkumar, K. Devendranath; Kumar, B. Monoj; Krishnan, M. Gokul; Dev, Sidarth; Bhalodi, Aman Jayesh; Arivazhagan, N.; Narayanan, S.

    2015-01-01

    This research article addresses the joining of 5 mm thick plates of Inconel 718 by activated flux tungsten inert gas (A-TIG) welding process using SiO 2 and TiO 2 fluxes. Microstructure studies inferred the presence of Nb rich eutectics and/or laves phase in the fusion zone of the A-TIG weldments. Tensile studies corroborated that the ultimate tensile strength of TiO 2 flux assisted weldments (885 MPa) was better compared to SiO 2 flux assisted weldments (815 MPa) and the failure was observed in the parent metal for both the cases. Impact test results portrayed that both the weldments were inferior in toughness as compared to the parent metal, which was due to the presence of oxide inclusions. Also, the study investigated the structure–property relationships of the A-TIG weldments of Inconel 718

  19. Studies on the weldability, microstructure and mechanical properties of activated flux TIG weldments of Inconel 718

    Energy Technology Data Exchange (ETDEWEB)

    Ramkumar, K. Devendranath, E-mail: ramdevendranath@gmail.com; Kumar, B. Monoj; Krishnan, M. Gokul; Dev, Sidarth; Bhalodi, Aman Jayesh; Arivazhagan, N.; Narayanan, S.

    2015-07-15

    This research article addresses the joining of 5 mm thick plates of Inconel 718 by activated flux tungsten inert gas (A-TIG) welding process using SiO{sub 2} and TiO{sub 2} fluxes. Microstructure studies inferred the presence of Nb rich eutectics and/or laves phase in the fusion zone of the A-TIG weldments. Tensile studies corroborated that the ultimate tensile strength of TiO{sub 2} flux assisted weldments (885 MPa) was better compared to SiO{sub 2} flux assisted weldments (815 MPa) and the failure was observed in the parent metal for both the cases. Impact test results portrayed that both the weldments were inferior in toughness as compared to the parent metal, which was due to the presence of oxide inclusions. Also, the study investigated the structure–property relationships of the A-TIG weldments of Inconel 718.

  20. Experience gained from high heat flux actively cooled PFCs in Tore Supra

    International Nuclear Information System (INIS)

    Grosman, A.; Bayetti, P.; Brosset, C.; Bucalossi, J.; Cordier, J.J.; Durocher, A.; Escourbiac, F.; Ghendrih, Ph.; Guilhem, D.; Gunn, J.; Loarer, T.; Lipa, M.; Mitteau, R.; Pegourie, B.; Reichle, R.; Schlosser, J.; Tsitrone, E.; Vallet, J.C.

    2005-01-01

    The implementation of actively cooled high heat flux plasma facing components (PFCs) is one of the major ingredients required for operating the Tore Supra tokamak with very long pulses. A pioneering activity has been developed in this field from the very beginning of the device operation that is today culminating with the routine operation of an actively cooled toroidal pumped limiter (TPL) capable to sustain up to 10 MW/m 2 of nominal convected heat flux. Technical information is drawn from the whole development up to the industrialisation and focuses on a number of critical issues, such as bonding technology analysis, manufacture processes, repair processes, destructive and non-destructive testing. The actual experience in Tore Supra allows to address the question of D retention on carbon walls. Redeposition on surfaces without plasma flux is suspected to cause the final 'burial' of about half of the injected gas during long discharges

  1. Console video games, postural activity, and motion sickness during passive restraint.

    Science.gov (United States)

    Chang, Chih-Hui; Pan, Wu-Wen; Chen, Fu-Chen; Stoffregen, Thomas A

    2013-08-01

    We examined the influence of passive restraint on postural activity and motion sickness in individuals who actively controlled a potentially nauseogenic visual motion stimulus (a driving video game). Twenty-four adults (20.09 ± 1.56 years; 167.80 ± 7.94 cm; 59.02 ± 9.18 kg) were recruited as participants. Using elastic bands, standing participants were passively restrained at the head, shoulders, hips, and knees. During restraint, participants played (i.e., controlled) a driving video game (a motorcycle race), for 50 min. During game play, we recorded the movement of the head and torso, using a magnetic tracking system. Following game play, participants answered a forced choice, yes/no question about whether they were motion sick, and were assigned to sick and well groups on this basis. In addition, before and after game play, participants completed the Simulator Sickness Questionnaire, which provided numerical ratings of the severity of individual symptoms. Five of 24 participants (20.83 %) reported motion sickness. Participants moved despite being passively restrained. Both the magnitude and the temporal dynamics of movement differed between the sick and well groups. The results show that passive restraint of the body can reduce motion sickness when the nauseogenic visual stimulus is under participants' active control and confirm that motion sickness is preceded by distinct patterns of postural activity even during passive restraint.

  2. Kinematic model of some types of motion of matter in active regions

    International Nuclear Information System (INIS)

    Platov, Yu.V.

    1983-01-01

    The kinematics of matter motion in variable magnetic fields of active regions on the Sun in the MHD approximation of a strong field and cold plasma is investigated. It is shown that the variation of sunspot magnetic moments lead to the development of different active phenomena in the solar atmosphere. The development of such phenomena at first can occur at the phase of active region growth, when new sunspots together with developed sunspots emerge in an active region or relative motions take place in a sunspot group

  3. Motion sickness and tilts of the inertial force environment : Active suspension systems vs. active passengers

    NARCIS (Netherlands)

    Golding, J. F.; van der Bles, W.; Bos, J. E.; Haynes, T.; Gresty, M. A.

    2003-01-01

    Background: Maneuvering in vehicles exposes occupants to low frequency forces (<1 Hz) which can provoke motion sickness. Hypothesis: Aligning with the tilting inertial resultant (gravity + imposed horizontal acceleration: gravito-inertial force (GIF)) may reduce motion sickness when tilting is

  4. Development of high flux thermal neutron generator for neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Vainionpaa, Jaakko H., E-mail: hannes@adelphitech.com [Adelphi Technology, 2003 E Bayshore Rd, Redwood City, CA 94063 (United States); Chen, Allan X.; Piestrup, Melvin A.; Gary, Charles K. [Adelphi Technology, 2003 E Bayshore Rd, Redwood City, CA 94063 (United States); Jones, Glenn [G& J Jones Enterprice, 7486 Brighton Ct, Dublin, CA 94568 (United States); Pantell, Richard H. [Department of Electrical Engineering, Stanford University, Stanford, CA (United States)

    2015-05-01

    The new model DD110MB neutron generator from Adelphi Technology produces thermal (<0.5 eV) neutron flux that is normally achieved in a nuclear reactor or larger accelerator based systems. Thermal neutron fluxes of 3–5 · 10{sup 7} n/cm{sup 2}/s are measured. This flux is achieved using four ion beams arranged concentrically around a target chamber containing a compact moderator with a central sample cylinder. Fast neutron yield of ∼2 · 10{sup 10} n/s is created at the titanium surface of the target chamber. The thickness and material of the moderator is selected to maximize the thermal neutron flux at the center. The 2.5 MeV neutrons are quickly thermalized to energies below 0.5 eV and concentrated at the sample cylinder. The maximum flux of thermal neutrons at the target is achieved when approximately half of the neutrons at the sample area are thermalized. In this paper we present simulation results used to characterize performance of the neutron generator. The neutron flux can be used for neutron activation analysis (NAA) prompt gamma neutron activation analysis (PGNAA) for determining the concentrations of elements in many materials. Another envisioned use of the generator is production of radioactive isotopes. DD110MB is small enough for modest-sized laboratories and universities. Compared to nuclear reactors the DD110MB produces comparable thermal flux but provides reduced administrative and safety requirements and it can be run in pulsed mode, which is beneficial in many neutron activation techniques.

  5. Dosimetry of mixed gamma - neutron fluxes in the active zone of working reactor and gamma-flux after quenching

    International Nuclear Information System (INIS)

    Mussaeva, M.A.; Zinov'ev, V.; Ibragimova, E.M.; Muminov, M.I.

    2006-01-01

    Full text: For carrying out experiments in the channels of nuclear reactor, it is necessary to know the distribution of neutron flux and the intensity of accompanying gamma-radiation both in the working and quenched regimes. Dosimetric parameter of transparent dielectrics is based on the effect of monotonous changing of optical absorption or luminescence under neutrons and/or gamma-radiation. While the radioactivity induced in an element monitor is proportional only to a neutron fluence beginning from a threshold energy. Therefore the aim of this work was to determine the values of neutron and gamma-component fluxes separately and evaluate the contribution of each into the defect production in dielectrics. We used very pure quartz glass of KU-1 type, produced in Russian State Optical Institute by fusion from SiCl 4 in the mixed flow of O 2 +H 2 (impurities of Cl and OH up to 10 -2 % and the rest - below 10 -4 %), SiO 2 glasses with 30 % Ba, and also pure Ni wire. Since under irradiation in the working reactor samples were undergone mixed neutron and gamma fluxes, we suggested determination of intensity of gamma-radiation from radio-nuclides (products of uranium fission) after quenching the reactor by the current of ionization chamber and glass dosimeters. Samples of SiO 2 -BaO together with Ni monitors were irradiated for 1 hour in 18 channels of the active zone of the working reactor both in the sealed ampoules and in the contact with water of the 1-st cooling circuit at 40 deg C. The linear dependence of the induced optical density on the absorbed dose of n 0 + γ-radiation was obtained. Ni -monitors not sensitive to γ-radiation gained the induced radioactivity proportional to the absorbed energy of neutron flux above 1 MeV. Neutron fluxes in the 18 channels varied from 9.53·10 11 to 1.21·10 13 cm -2 s -1 corresponding to fluences from 3.43·10 15 to 4.3·10 16 cm -2 . Optical density of band 215 nm ascertained to E ' - center, which is ≡ Si * near oxygen

  6. Neutron activation analysis: Modelling studies to improve the neutron flux of Americium-Beryllium source

    Energy Technology Data Exchange (ETDEWEB)

    Didi, Abdessamad; Dadouch, Ahmed; Tajmouati, Jaouad; Bekkouri, Hassane [Advanced Technology and Integration System, Dept. of Physics, Faculty of Science Dhar Mehraz, University Sidi Mohamed Ben Abdellah, Fez (Morocco); Jai, Otman [Laboratory of Radiation and Nuclear Systems, Dept. of Physics, Faculty of Sciences, Tetouan (Morocco)

    2017-06-15

    Americium–beryllium (Am-Be; n, γ) is a neutron emitting source used in various research fields such as chemistry, physics, geology, archaeology, medicine, and environmental monitoring, as well as in the forensic sciences. It is a mobile source of neutron activity (20 Ci), yielding a small thermal neutron flux that is water moderated. The aim of this study is to develop a model to increase the neutron thermal flux of a source such as Am-Be. This study achieved multiple advantageous results: primarily, it will help us perform neutron activation analysis. Next, it will give us the opportunity to produce radio-elements with short half-lives. Am-Be single and multisource (5 sources) experiments were performed within an irradiation facility with a paraffin moderator. The resulting models mainly increase the thermal neutron flux compared to the traditional method with water moderator.

  7. Neutron flux variations near the Earth’s crust. A possible tectonic activity detection

    Directory of Open Access Journals (Sweden)

    B. M. Kuzhevskij

    2003-01-01

    Full Text Available The present work contains some results of observations of neutron flux variations near the Earth’s surface. The Earth’s crust is determined to be a significant source of thermal and slow neutrons, originated from the interaction between the nuclei of the elements of the Earth’s crust and the atmosphere and α-particles, produced by decay of radioactive gases (Radon, Thoron and Actinon. In turn, variations of radioactive gases exhalation is connected with geodynamical processes in the Earth’s crust, including tectonic activity. This determined relation between the processes in the Earth’s crust and neutrons’ flux allow to use variations of thermal and slow neutrons’ flux in order to observe increasing tectonic activity and to develop methods for short-term prediction of natural hazards.

  8. Airborne particulate concentrations and fluxes at an active uranium mill tailings site

    International Nuclear Information System (INIS)

    Sehmel, G.A.

    1978-01-01

    Direct measurements of airborne particulate concentrations and fluxes of transported mill tailing materials were measured at an active mill tailings site. Experimental measurement equipment consisted of meteorological instrumentation to automatically activate total particulate air samplers as a function of wind speed increments and direction, as well as particle cascade impactors to measure airborne respirable concentrations as a function of particle size. In addition, an inertial impaction device measured nonrespirable fluxes of airborne particles. Caclulated results are presented in terms of the airborne solid concentration in g/m 3 , the horizontal airborne mass flux in g/(m 2 -day) for total collected nonrespirable particles and the radionuclide concentrations in dpm/g as a function of particle diameter for respirable and nonrespirable particles

  9. Visuotactile motion congruence enhances gamma-band activity in visual and somatosensory cortices.

    Science.gov (United States)

    Krebber, Martin; Harwood, James; Spitzer, Bernhard; Keil, Julian; Senkowski, Daniel

    2015-08-15

    When touching and viewing a moving surface our visual and somatosensory systems receive congruent spatiotemporal input. Behavioral studies have shown that motion congruence facilitates interplay between visual and tactile stimuli, but the neural mechanisms underlying this interplay are not well understood. Neural oscillations play a role in motion processing and multisensory integration. They may also be crucial for visuotactile motion processing. In this electroencephalography study, we applied linear beamforming to examine the impact of visuotactile motion congruence on beta and gamma band activity (GBA) in visual and somatosensory cortices. Visual and tactile inputs comprised of gratings that moved either in the same or different directions. Participants performed a target detection task that was unrelated to motion congruence. While there were no effects in the beta band (13-21Hz), the power of GBA (50-80Hz) in visual and somatosensory cortices was larger for congruent compared with incongruent motion stimuli. This suggests enhanced bottom-up multisensory processing when visual and tactile gratings moved in the same direction. Supporting its behavioral relevance, GBA was correlated with shorter reaction times in the target detection task. We conclude that motion congruence plays an important role for the integrative processing of visuotactile stimuli in sensory cortices, as reflected by oscillatory responses in the gamma band. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Unified theory of dislocation motion including thermal activation and inertial effects

    International Nuclear Information System (INIS)

    Isaac, R.D.; Granato, A.V.

    1979-01-01

    Transition-state rate theory has generally been used to explain the temperature dependence of the flow stress of a crystal. However, the existence of a change in the flow stress during the superconducting transition indicates the presence of inertial effects in which dislocations overcome obstacles mechanically rather than thermally. It is shown here that the thermally activated and the inertial overcoming of obstacles are not unrelated but can both be derived from principles of stochastic motion. This leads to a theory of dislocation motion that includes both thermal activation and inertial effects. It is also shown that a distribution of activation energies must be considered to account for the experimental data

  11. Successive X-class Flares and Coronal Mass Ejections Driven by Shearing Motion and Sunspot Rotation in Active Region NOAA 12673

    Science.gov (United States)

    Yan, X. L.; Wang, J. C.; Pan, G. M.; Kong, D. F.; Xue, Z. K.; Yang, L. H.; Li, Q. L.; Feng, X. S.

    2018-03-01

    We present a clear case study on the occurrence of two successive X-class flares, including a decade-class flare (X9.3) and two coronal mass ejections (CMEs) triggered by shearing motion and sunspot rotation in active region NOAA 12673 on 2017 September 6. A shearing motion between the main sunspots with opposite polarities began on September 5 and lasted even after the second X-class flare on September 6. Moreover, the main sunspot with negative polarity rotated around its umbral center, and another main sunspot with positive polarity also exhibited a slow rotation. The sunspot with negative polarity at the northwest of the active region also began to rotate counterclockwise before the onset of the first X-class flare, which is related to the formation of the second S-shaped structure. The successive formation and eruption of two S-shaped structures were closely related to the counterclockwise rotation of the three sunspots. The existence of a flux rope is found prior to the onset of two flares by using nonlinear force-free field extrapolation based on the vector magnetograms observed by Solar Dynamics Observatory/Helioseismic and Magnetic Image. The first flux rope corresponds to the first S-shaped structures mentioned above. The second S-shaped structure was formed after the eruption of the first flux rope. These results suggest that a shearing motion and sunspot rotation play an important role in the buildup of the free energy and the formation of flux ropes in the corona that produces solar flares and CMEs.

  12. Complex Human Activity Recognition Using Smartphone and Wrist-Worn Motion Sensors

    NARCIS (Netherlands)

    Shoaib, M.; Bosch, S.; Durmaz, O.; Scholten, Johan; Havinga, Paul J.M.

    2016-01-01

    The position of on-body motion sensors plays an important role in human activity recognition. Most often, mobile phone sensors at the trouser pocket or an equivalent position are used for this purpose. However, this position is not suitable for recognizing activities that involve hand gestures, such

  13. Activity Recognition Invariant to Sensor Orientation with Wearable Motion Sensors.

    Science.gov (United States)

    Yurtman, Aras; Barshan, Billur

    2017-08-09

    Most activity recognition studies that employ wearable sensors assume that the sensors are attached at pre-determined positions and orientations that do not change over time. Since this is not the case in practice, it is of interest to develop wearable systems that operate invariantly to sensor position and orientation. We focus on invariance to sensor orientation and develop two alternative transformations to remove the effect of absolute sensor orientation from the raw sensor data. We test the proposed methodology in activity recognition with four state-of-the-art classifiers using five publicly available datasets containing various types of human activities acquired by different sensor configurations. While the ordinary activity recognition system cannot handle incorrectly oriented sensors, the proposed transformations allow the sensors to be worn at any orientation at a given position on the body, and achieve nearly the same activity recognition performance as the ordinary system for which the sensor units are not rotatable. The proposed techniques can be applied to existing wearable systems without much effort, by simply transforming the time-domain sensor data at the pre-processing stage.

  14. Gamma-ray-spectroscopy following high-flux 14-MeV neutron activation

    Energy Technology Data Exchange (ETDEWEB)

    Williams, R.E.

    1981-10-12

    The Rotating Target Neutron Source (RTNS-I), a high-intensity source of 14-MeV neutrons at the Lawrence Livermore National Laboratory (LLNL), has been used for applications in activation analysis, inertial-confinement-fusion diagnostic development, and fission decay-heat studies. The fast-neutron flux from the RTNS-I is at least 50 times the maximum fluxes available from typical neutron generators, making these applications possible. Facilities and procedures necessary for gamma-ray spectroscopy of samples irradiated at the RTNS-I were developed.

  15. Gamma-ray-spectroscopy following high-flux 14-MeV neutron activation

    International Nuclear Information System (INIS)

    Williams, R.E.

    1981-01-01

    The Rotating Target Neutron Source (RTNS-I), a high-intensity source of 14-MeV neutrons at the Lawrence Livermore National Laboratory (LLNL), has been used for applications in activation analysis, inertial-confinement-fusion diagnostic development, and fission decay-heat studies. The fast-neutron flux from the RTNS-I is at least 50 times the maximum fluxes available from typical neutron generators, making these applications possible. Facilities and procedures necessary for gamma-ray spectroscopy of samples irradiated at the RTNS-I were developed

  16. Use of Germanium as comparator and integral monitor of neutron flux in activation analysis

    International Nuclear Information System (INIS)

    Furnari, Juan C.; Cohen, Isaac M.; Arribere, Maria A.; Kestelman, Abraham J.

    1997-01-01

    The possibility of using germanium as monitor of the thermal and epithermal components of the neutron flux, and comparator in parametric activation analysis, is discussed. The advantages and drawbacks associated to the use of this element are commented on, and the comparison with zirconium, in terms of the determination relative error, is performed. The utilisation of germanium as integral flux monitor, including the fast component of the neutron spectrum, is also discussed. Data corresponding to measurements of k 0 factor for the most relevant gamma transitions from Ge-75 and Be-77 are presented, as well as the results of the reference material analysis, employing germanium as flux monitor and comparator in a simultaneous way. (author). 8 refs., 3 figs., 2 tabs

  17. Determination of neutron flux with an arbitrary energy distribution by measurement of irradiated foils activity

    International Nuclear Information System (INIS)

    Ljubenov, V.; Milosevic, M.

    2003-01-01

    A procedure for the neutron flux determination in a neutron field with an arbitrary energy spectrum, based on the using of standard methods for the measurement of irradiated foils activity and on the application of the SCALE-4.4a code system for averaged cross section calculation is described in this paper. Proposed procedure allows to include the energy spectrum of neutron flux reestablished in the location of irradiated foils and the resonance self-shielding effects in the foils also. Example application of this procedure is given for the neutron flux determination inside the neutron filter with boron placed in the centre of heavy water critical assembly RB at the Vinca Institute (author)

  18. Anomalous high-frequency wave activity flux preceding anomalous changes in the Northern polar jet

    Science.gov (United States)

    Nakamura, Mototaka; Kadota, Minoru; Yamane, Shozo

    2010-05-01

    Anomalous forcing by quasi-geostrophic (QG) waves has been reported as an important forcing factor in the Northern Annular Mode (NAM) in recent literatures. In order to shed a light on the dynamics of the NAM from a different angle, we have examined anomalous behavior of the winter jets in the upper troposphere and stratosphere by focusing our diagnosis on not the anomalous geopotential height (Z) itself, but on the anomalous change in the Z (dZ) between two successive months and preceding transient QG wave activity flux during the cold season. We calculated EOFs of dZ between two successive months at 150hPa for a 46-year period, from 1958 to 2003, using the monthly mean NCEP reanalysis data. We then formed anomaly composites of changes in Z and the zonal velocity (U), as well as the preceding and following wave activity flux, Z, U, and temperature at various heights, for both positive and negative phases of the first EOF. For the wave forcing fields, we adopted the diagnostic system for the three-dimensional QG transient wave activity flux in the zonally-varying three-dimensional mean flow developed by Plumb (1986) with a slight modification in its application to the data. Our choice of the Plumb86 is based on the fact that the winter mean flow in the Northern Hemisphere is characterized by noticeable zonal asymmetry, and has a symbiotic relationship with waves in the extra-tropics. The Plumb86 flux was calculated for high-frequency (period of 2 to 7 days) and low-frequency (period of 10 to 20 days) waves with the ultra-low-frequency (period of 30 days or longer) flow as the reference state for each time frame of the 6 hourly NCEP reanalysis data from 1958 to 2003. By replacing the mean flow with the ultra-low-frequency flow in the application of the Plumb86 formula, the flux fields were calculated as time series at 6 hour intervals. The time series of the wave activity flux was then averaged for each month. The patterns of composited anomalous dZ and dU clearly

  19. DEFINITION AND ANALYSIS OF MOTION ACTIVITY AFTER-STROKE PATIENT FROM THE VIDEO STREAM

    Directory of Open Access Journals (Sweden)

    M. Yu. Katayev

    2014-01-01

    Full Text Available This article describes an approach to the assessment of motion activity of man in after-stroke period, allowing the doctor to get new information to give a more informed recommendations on rehabilitation treatment than in traditional approaches. Consider description of the hardware-software complex for determination and analysis of motion activity after-stroke patient for the video stream. The article provides a description of the complex, its algorithmic filling and the results of the work on the example of processing of the actual data. The algorithms and technology to significantly accelerate the gait analysis and improve the quality of diagnostics post-stroke patients.

  20. Indirect wrist MR arthrography: the effects of passive motion versus active exercise

    Energy Technology Data Exchange (ETDEWEB)

    Schweitzer, M.E.; Natale, P.; Winalski, C.S.; Culp, R. [Thomas Jefferson University Hospital, Department of Radiology, Philadelphia, PA (United States)

    2000-01-01

    Purpose. In the wrist, to determine whether passive motion or active exercise yields a better indirect MR arthrographic effect following intravenous gadolinium administration.Design and patients. Twenty-six consecutive patients were studied by indirect wrist MR arthrography. In half active exercise and in half passive motion was performed. Four regions of interest were studied including the distal radioulnar joint, the radiocarpal joint, the midcarpal joint, and the triangular fibrocartilage. Ranges and means of signal intensity were calculated. Surgical follow-up was performed in 22 patients.Results. The joint fluid intensity was greatest in the distal radioulnar joint. Fluid signal intensity was greater and more consistent in the passive motion group although the results did not achieve statistical significance. Imaging accuracy appeared similar in the two groups and was excellent for the triangular fibrocartilage (100%) and scapholunate ligaments (96%).Conclusion. Active exercise and passive motion yield similar degrees of wrist arthrographic effect, but the effect of passive motion is somewhat more consistent. Preliminary data show good accuracy for internal derangements. (orig.)

  1. Self-shielding coefficient and thermal flux depression factor of voluminous sample in neutron activation analysis

    International Nuclear Information System (INIS)

    Noorddin Ibrahim; Rosnie Akang

    2009-01-01

    Full text: One of the major problems encountered during the irradiation of large inhomogeneous samples in performing activation analysis using neutron is the perturbation of the neutron field due to absorption and scattering of neutron within the sample as well as along the neutron guide in the case of prompt gamma activation analysis. The magnitude of this perturbation shown by self-shielding coefficient and flux depression depend on several factors including the average neutron energy, the size and shape of the sample, as well as the macroscopic absorption cross section of the sample. In this study, we use Monte Carlo N-Particle codes to simulate the variation of neutron self-shielding coefficient and thermal flux depression factor as a function of the macroscopic thermal absorption cross section. The simulation works was carried out using the high performance computing facility available at UTM while the experimental work was performed at the tangential beam port of Reactor TRIGA PUSPATI, Malaysia Nuclear Agency. The neutron flux measured along the beam port is found to be in good agreement with the simulated data. Our simulation results also reveal that total flux perturbation factor decreases as the value of absorption increases. This factor is close to unity for low absorbing sample and tends towards zero for strong absorber. In addition, sample with long mean chord length produces smaller flux perturbation than the shorter mean chord length. When comparing both the graphs of self-shielding factor and total disturbance, we can conclude that the total disturbance of the thermal neutron flux on the large samples is dominated by the self-shielding effect. (Author)

  2. Measurement of thermal, epithermal and fast neutron flux in the IEA-R1 reactor by the foil activation method

    International Nuclear Information System (INIS)

    Koskinas, M.F.

    1979-01-01

    Experimental and theoretical details of the foil activation method applied to neutrons flux measurements at the IEA-R1 reactor are presented. The thermal - and epithermal - neutron flux were determined form activation measurements of gold, cobalt and manganese foils; and for the fast neutron flux determination, aluminum, iron and nickel foils were used. The measurements of the activity induced in the metal foils were performed using a Ge-Li gamma spectrometry system. In each energy range of the reactor neutron spectrum, the agreement among the experimental flux values obtained using the three kind of materials, indicates the consistency of the theoretical approach and of the nuclear parameters selected. (Author) [pt

  3. Extending Counter-streaming Motion from an Active Region Filament to a Sunspot Light Bridge

    Science.gov (United States)

    Wang, Haimin; Liu, Rui; Li, Qin; Liu, Chang; Deng, Na; Xu, Yan; Jing, Ju; Wang, Yuming; Cao, Wenda

    2018-01-01

    We analyze high-resolution observations from the 1.6 m telescope at Big Bear Solar Observatory that cover an active region filament. Counter-streaming motions are clearly observed in the filament. The northern end of the counter-streaming motions extends to a light bridge, forming a spectacular circulation pattern around a sunspot, with clockwise motion in the blue wing and counterclockwise motion in the red wing, as observed in the Hα off-bands. The apparent speed of the flow is around 10–60 km s‑1 in the filament, decreasing to 5–20 km s‑1 in the light bridge. The most intriguing results are the magnetic structure and the counter-streaming motions in the light bridge. Similar to those in the filament, the magnetic fields show a dominant transverse component in the light bridge. However, the filament is located between opposed magnetic polarities, while the light bridge is between strong fields of the same polarity. We analyze the power of oscillations with the image sequences of constructed Dopplergrams, and find that the filament’s counter-streaming motion is due to physical mass motion along fibrils, while the light bridge’s counter-streaming motion is due to oscillation in the direction along the line-of-sight. The oscillation power peaks around 4 minutes. However, the section of the light bridge next to the filament also contains a component of the extension of the filament in combination with the oscillation, indicating that some strands of the filament are extended to and rooted in that part of the light bridge.

  4. Can origin of the 2400-year cycle of solar activity be caused by solar inertial motion?

    Directory of Open Access Journals (Sweden)

    I. Charvátová

    Full Text Available A solar activity cycle of about 2400 years has until now been of uncertain origin. Recent results indicate it is caused by solar inertial motion. First we describe the 178.7-year basic cycle of solar motion. The longer cycle, over an 8000 year interval, is found to average 2402.2 years. This corresponds to the Jupiter/Heliocentre/Barycentre alignments (9.8855 × 243. Within each cycle an exceptional segment of 370 years has been found characterized by a looping pattern by a trefoil or quasitrefoil geometry. Solar activity, evidenced by 14C tree-ring proxies, shows the same pattern. Solar motion is computable in advance, so this provides a basis for future predictive assessments. The next 370-year segment will occur between AD 2240 and 2610.

    Key words: Solar physics (celestial mechanics

  5. COSANI-2, Gamma Doses from SABINE Calculation, Activity from ANISN Flux Calculation

    International Nuclear Information System (INIS)

    Dupont, C.

    1975-01-01

    1 - Nature of physical problem solved: Retrieval of SABINE and/or ANISN results. Calculates in case of SABINE results the individual contributions of capture gamma rays in each region to the total gamma dose and to the total gamma heating may calculate in case of ANISN new activity rates starting from ANISN flux saved on tape and activity cross sections taken on an ANISN binary library tape. The program can draw on a BENSON plotter any of the following quantities: - group flux; - activity rates; - dose rates; - neutron spectra for SABINE; - neutron or gamma direct or adjoint spectra for ANISN; - gamma heating and dose rate for SABINE including individual contributions from each region. Several ANISN and/or SABINE cases can be drawn on the same graph for comparison purposes. 2 - Restrictions on the complexity of the problem: Maximum number of: - tapes containing ANISN and/or SABINE results: 5; - curves per graph: 3; - regions: 40; - points per curve: 500; - energy groups: 200

  6. Solar activity associated with an unusual series of microwave flux decreases

    International Nuclear Information System (INIS)

    Sawyer, C.

    1976-01-01

    East-limb passage of an activity complex in the spring of 1974 was accompanied by a remarkable series of microwave flux decreases. Within an interval of four days, two post-burst decreases and five 'absorption' events occurred, along with two oscillations. Hα patrol films and a spectrogram show a surge and flare sprays with an unusually large velocity of approach at the time of the first post-burst decrease. Two other 'absorption' events were loosely associated with prominence activations, but no outstanding Hα activity was seen at the time of the oscillations. These observations, along with published data, show that the flux decreases followed only flares that lay westward of the major microwave source; ejections from this location would likely have overlain the source while the region was near the east limb. Absorption by flare-ejected material is a plausible, though not exclusive, explanation of these events. (author)

  7. Image-based synchronization of force and bead motion in active electromagnetic microrheometry

    International Nuclear Information System (INIS)

    Park, Chang-Young; Saleh, Omar A

    2014-01-01

    In the past, electromagnetic tweezers have been used to make active microrheometers. An active microrheometer measures the dynamic mechanical properties of a material from the motion of embedded particles under external force, e.g. a sinusoidal magnetic force generated by a sinusoidal current on a coil. The oscillating amplitude and the phase lag of the motion are then used to estimate the material’s dynamic mechanical properties. The phase lag, in particular, requires precise synchronization of the particle motion with the external force. In previous works, synchronization difficulties have arisen from measuring two parameters with two instruments, one of them being a camera. We solved the synchronization issue by measuring two parameters with a single instrument, the camera alone. From captured images, particles can be tracked in three dimensions through an image-analysis algorithm while the current on the coil can be measured from the brightness of the image; this enables simultaneous synchronization of the phases of the driving current on the electromagnet coil and the motion of the magnetic probe particle. We calibrate the phase delay between the magnetic force and the particle’s motion in glycerol and confirm the calibration with a Hall probe. The technique is further tested by measuring the shear modulus of a polyacrylamide gel, and comparing the results to those obtained using a conventional rheometer. (paper)

  8. EVOLUTION OF SPINNING AND BRAIDING HELICITY FLUXES IN SOLAR ACTIVE REGION NOAA 10930

    Energy Technology Data Exchange (ETDEWEB)

    Ravindra, B. [Indian Institute of Astrophysics, Koramangala, Bangalore 560 034 (India); Yoshimura, Keiji [Department of Physics, Montana State University Bozeman, MT 59717 (United States); Dasso, Sergio, E-mail: ravindra@iiap.res.in, E-mail: yosimura@solar.physics.montana.edu, E-mail: dasso@df.uba.ar [Instituto de Astronomia y Fisica del Espacio (CONICET-UBA), 1428 Buenos Aires (Argentina)

    2011-12-10

    The line-of-sight magnetograms from Solar Optical Telescope Narrowband Filter Imager observations of NOAA Active Region 10930 have been used to study the evolution of spinning and braiding helicities over a period of five days starting from 2006 December 9. The north (N) polarity sunspot was the follower and the south (S) polarity sunspot was the leader. The N-polarity sunspot in the active region was rotating in the counterclockwise direction. The rate of rotation was small during the first two days of observations and it increased up to 8 Degree-Sign hr{sup -1} on the third day of the observations. On the fourth and fifth days it remained at 4 Degree-Sign hr{sup -1} with small undulations in its magnitude. The sunspot rotated about 260 Degree-Sign in the last three days. The S-polarity sunspot did not complete more than 20 Degree-Sign in five days. However, it changed its direction of rotation five times over a period of five days and injected both the positive and negative type of spin helicity fluxes into the corona. Through the five days, both the positive and negative sunspot regions injected equal amounts of spin helicity. The total injected helicity is predominantly negative in sign. However, the sign of the spin and braiding helicity fluxes computed over all the regions were reversed from negative to positive five times during the five-day period of observations. The reversal in spinning helicity flux was found before the onset of the X3.4-class flare, too. Though, the rotating sunspot has been observed in this active region, the braiding helicity has contributed more to the total accumulated helicity than the spinning helicity. The accumulated helicity is in excess of -7 Multiplication-Sign 10{sup 43} Mx{sup 2} over a period of five days. Before the X3.4-class flare that occurred on 2006 December 13, the rotation speed and spin helicity flux increased in the S-polarity sunspot. Before the flare, the total injected helicity was larger than -6

  9. Parkinson-related changes of activation in visuomotor brain regions during perceived forward self-motion.

    Directory of Open Access Journals (Sweden)

    Anouk van der Hoorn

    Full Text Available Radial expanding optic flow is a visual consequence of forward locomotion. Presented on screen, it generates illusionary forward self-motion, pointing at a close vision-gait interrelation. As particularly parkinsonian gait is vulnerable to external stimuli, effects of optic flow on motor-related cerebral circuitry were explored with functional magnetic resonance imaging in healthy controls (HC and patients with Parkinson's disease (PD. Fifteen HC and 22 PD patients, of which 7 experienced freezing of gait (FOG, watched wide-field flow, interruptions by narrowing or deceleration and equivalent control conditions with static dots. Statistical parametric mapping revealed that wide-field flow interruption evoked activation of the (pre-supplementary motor area (SMA in HC, which was decreased in PD. During wide-field flow, dorsal occipito-parietal activations were reduced in PD relative to HC, with stronger functional connectivity between right visual motion area V5, pre-SMA and cerebellum (in PD without FOG. Non-specific 'changes' in stimulus patterns activated dorsolateral fronto-parietal regions and the fusiform gyrus. This attention-associated network was stronger activated in HC than in PD. PD patients thus appeared compromised in recruiting medial frontal regions facilitating internally generated virtual locomotion when visual motion support falls away. Reduced dorsal visual and parietal activations during wide-field optic flow in PD were explained by impaired feedforward visual and visuomotor processing within a magnocellular (visual motion functional chain. Compensation of impaired feedforward processing by distant fronto-cerebellar circuitry in PD is consistent with motor responses to visual motion stimuli being either too strong or too weak. The 'change'-related activations pointed at covert (stimulus-driven attention.

  10. sEMG during Whole-Body Vibration Contains Motion Artifacts and Reflex Activity

    Directory of Open Access Journals (Sweden)

    Karin Lienhard

    2015-01-01

    Full Text Available The purpose of this study was to determine whether the excessive spikes observed in the surface electromyography (sEMG spectrum recorded during whole-body vibration (WBV exercises contain motion artifacts and/or reflex activity. The occurrence of motion artifacts was tested by electrical recordings of the patella. The involvement of reflex activity was investigated by analyzing the magnitude of the isolated spikes during changes in voluntary background muscle activity. Eighteen physically active volunteers performed static squats while the sEMG was measured of five lower limb muscles during vertical WBV using no load and an additional load of 33 kg. In order to record motion artifacts during WBV, a pair of electrodes was positioned on the patella with several layers of tape between skin and electrodes. Spectral analysis of the patella signal revealed recordings of motion artifacts as high peaks at the vibration frequency (fundamental and marginal peaks at the multiple harmonics were observed. For the sEMG recordings, the root mean square of the spikes increased with increasing additional loads (p < 0.05, and was significantly correlated to the sEMG signal without the spikes of the respective muscle (r range: 0.54 - 0.92, p < 0.05. This finding indicates that reflex activity might be contained in the isolated spikes, as identical behavior has been found for stretch reflex responses evoked during direct vibration. In conclusion, the spikes visible in the sEMG spectrum during WBV exercises contain motion artifacts and possibly reflex activity.

  11. Effect of body orientation on proprioception during active and passive motions

    NARCIS (Netherlands)

    Niessen, M.H.M.; Veeger, H.E.J.; Janssen, T.W.J.

    2009-01-01

    Objective: To investigate whether passive and active reproduction of joint position, as well as detection of passive motion (as measures of a subject's proprioception) of the shoulder differ while sitting compared with lying supine. Design: Shoulder proprioception of 28 healthy subjects (age, 22.2 ±

  12. Complex Human Activity Recognition Using Smartphone and Wrist-Worn Motion Sensors.

    Science.gov (United States)

    Shoaib, Muhammad; Bosch, Stephan; Incel, Ozlem Durmaz; Scholten, Hans; Havinga, Paul J M

    2016-03-24

    The position of on-body motion sensors plays an important role in human activity recognition. Most often, mobile phone sensors at the trouser pocket or an equivalent position are used for this purpose. However, this position is not suitable for recognizing activities that involve hand gestures, such as smoking, eating, drinking coffee and giving a talk. To recognize such activities, wrist-worn motion sensors are used. However, these two positions are mainly used in isolation. To use richer context information, we evaluate three motion sensors (accelerometer, gyroscope and linear acceleration sensor) at both wrist and pocket positions. Using three classifiers, we show that the combination of these two positions outperforms the wrist position alone, mainly at smaller segmentation windows. Another problem is that less-repetitive activities, such as smoking, eating, giving a talk and drinking coffee, cannot be recognized easily at smaller segmentation windows unlike repetitive activities, like walking, jogging and biking. For this purpose, we evaluate the effect of seven window sizes (2-30 s) on thirteen activities and show how increasing window size affects these various activities in different ways. We also propose various optimizations to further improve the recognition of these activities. For reproducibility, we make our dataset publicly available.

  13. Thermally Activated Motion of Sodium Cations in Insulating Parent Low-Silica X Zeolite

    Science.gov (United States)

    Igarashi, Mutsuo; Jeglič, Peter; Mežnaršič, Tadej; Nakano, Takehito; Nozue, Yasuo; Watanabe, Naohiro; Arčon, Denis

    2017-07-01

    We report a 23Na spin-lattice relaxation rate, T1 - 1, in low-silica X zeolite. T1 - 1 follows multiple BPP-type behavior as a result of thermal motion of sodium cations in insulating material. The estimated lowest activation energy of 15 meV is much lower than 100 meV observed previously for sodium motion in heavily Na-loaded samples and is most likely attributed to short-distance jumps of sodium cations between sites within the same supercage.

  14. Enhancing the smoothness of joint motion induced by functional electrical stimulation using co-activation strategies

    Directory of Open Access Journals (Sweden)

    Ruppel Mirjana

    2017-09-01

    Full Text Available The motor precision of today’s neuroprosthetic devices that use artificial generation of limb motion using Functional Electrical Stimulation (FES is generally low. We investigate the adoption of natural co-activation strategies as present in antagonistic muscle pairs aiming to improve motor precision produced by FES. In a test in which artificial knee-joint movements were generated, we could improve the smoothness of FES-induced motion by 513% when applying co-activation during the phases in which torque production is switched between muscles – compared to no co-activation. We further demonstrated how the co-activation level influences the joint stiffness in a pendulum test.

  15. SHREDI, Neutron Flux and Neutron Activation in 2-D Shields by Removal Diffusion

    International Nuclear Information System (INIS)

    Daneri, A.; Toselli, G.

    1976-01-01

    1 - Nature of physical problem solved: SHREDI is a removal - diffusion neutron shielding code. The program computes neutron fluxes and activations in bidimensional sections (x,y or r,z) of the shield. It is also possible to consider shielding points with the same y or z coordinate (mono-dimensional problems). 2 - Method of solution: The integrals which define the removal fluxes are computed in some shield points by means of a particular algorithm based on the Simpson's and trapezoidal rules. For the diffusion calculation the finite difference method is used. The removal sources are interpolated in all diffusion points by Chebyshev polynomials. 3 - Restrictions on the complexity of the problem: Maxima: number of removal energy groups NGR = 40; number of diffusion energy groups NGD = 40; number of the reactor core and shield materials NCMP = 50; number of core mesh points in r (or x) direction for integral calculation = 75; number of core mesh points in z (or y) direction for integral calculation = 75; number of core mesh points in theta (or z) direction for integral calculation = 75; number of shield mesh points for the neutron flux calculation in r (or x) direction NPX = 200; number of shield mesh points for the neutron flux calculation in z (or y) direction NPY = 200; n.b. (NPX * NPY) le 12000

  16. Sensorless sliding mode torque control of an IPMSM drive based on active flux concept

    Directory of Open Access Journals (Sweden)

    A.A. Hassan

    2012-03-01

    Full Text Available This paper investigates a novel direct torque control of a sensorless interior permanent magnet synchronous motor based on a sliding mode technique. The speed and position of the interior permanent magnet synchronous motor are estimated online based on active flux concept. To overcome the large ripple content associated with the direct torque, a torque/flux sliding mode controller has been employed. Two integral surface functions are used to construct the sliding mode controller. The command voltage is estimated from the torque and flux errors based on the two switching functions. The idea of the total sliding mode is used to eliminate the problem of reaching phase stability. The space vector modulation is combined with the sliding mode controller to ensure minimum torque and flux ripples and provides high resolution voltage control. The proposed scheme has the advantages of simple implementation, and does not require an external signal injection. In addition, it combines the merits of the direct torque control, sliding mode controller, and space vector modulation besides to the sensorless control. Simulation works are carried out to demonstrate the ability of the proposed scheme at different operating conditions. The results confirm the high performance of the proposed scheme at standstill, low and high speeds including load disturbance and parameters variation.

  17. Active contour-based visual tracking by integrating colors, shapes, and motions.

    Science.gov (United States)

    Hu, Weiming; Zhou, Xue; Li, Wei; Luo, Wenhan; Zhang, Xiaoqin; Maybank, Stephen

    2013-05-01

    In this paper, we present a framework for active contour-based visual tracking using level sets. The main components of our framework include contour-based tracking initialization, color-based contour evolution, adaptive shape-based contour evolution for non-periodic motions, dynamic shape-based contour evolution for periodic motions, and the handling of abrupt motions. For the initialization of contour-based tracking, we develop an optical flow-based algorithm for automatically initializing contours at the first frame. For the color-based contour evolution, Markov random field theory is used to measure correlations between values of neighboring pixels for posterior probability estimation. For adaptive shape-based contour evolution, the global shape information and the local color information are combined to hierarchically evolve the contour, and a flexible shape updating model is constructed. For the dynamic shape-based contour evolution, a shape mode transition matrix is learnt to characterize the temporal correlations of object shapes. For the handling of abrupt motions, particle swarm optimization is adopted to capture the global motion which is applied to the contour in the current frame to produce an initial contour in the next frame.

  18. Relationships between Paraspinal Muscle Activity and Lumbar Inter-Vertebral Range of Motion

    OpenAIRE

    du Rose, Alister; Breen, Alan

    2016-01-01

    Abstract: Control of the lumbar spine requires contributions from both the active and passive sub-systems. Identifying interactions between these systems may provide insight into the mechanisms of low back pain. However, as a first step it is important to investigate what is normal. The purpose of this study was to explore the relationships between the lumbar inter-vertebral range of motion and paraspinal muscle activity during weight-bearing flexion in healthy controls using quantitative flu...

  19. Production of high-specific activity radionuclides using SM high-flux reactor

    International Nuclear Information System (INIS)

    Karelin, Ye.A.; Toporov, Yu.G.; Filimonov, V.T.; Vakhetov, F.Z.; Tarasov, V.A.; Kuznetsov, R.A.; Lebedev, V.M.; Andreev, O.I.; Melnik, M.I.; Gavrilov, V.D.

    1997-01-01

    The development of High Specific Activity (HSA) radionuclides production technologies is one of the directions of RIAR activity, and the high flux research reactor SM, having neutron flux density up to 2.10 15 cm -2 s 1 in a wide range of neutron spectra hardness, plays the principal role in this development. The use of a high-flux reactor for radionuclide production provides the following advantages: production of radionuclides with extremely high specific activity, decreasing of impurities content in irradiated targets (both radioactive and non-radioactive), cost-effective use of expensive isotopically enriched target materials. The production technologies of P-33, Gd-153, W-188, Ni-63, Fe-55,59, Sn-113,117m,119m, Sr- 89, applied in industry, nuclear medicine, research, etc, were developed by RIAR during the last 5-10 years. The research work included the development of calculation procedures for radionuclide reactor accumulation forecast, experimental determination of neutron cross-sections, the development of irradiated materials reprocessing procedures, isolation and purification of radionuclides. The principal results are reviewed in the paper. (authors)

  20. Increase in MST activity correlates with visual motion learning: A functional MRI study of perceptual learning.

    Science.gov (United States)

    Larcombe, Stephanie J; Kennard, Chris; Bridge, Holly

    2018-01-01

    Repeated practice of a specific task can improve visual performance, but the neural mechanisms underlying this improvement in performance are not yet well understood. Here we trained healthy participants on a visual motion task daily for 5 days in one visual hemifield. Before and after training, we used functional magnetic resonance imaging (fMRI) to measure the change in neural activity. We also imaged a control group of participants on two occasions who did not receive any task training. While in the MRI scanner, all participants completed the motion task in the trained and untrained visual hemifields separately. Following training, participants improved their ability to discriminate motion direction in the trained hemifield and, to a lesser extent, in the untrained hemifield. The amount of task learning correlated positively with the change in activity in the medial superior temporal (MST) area. MST is the anterior portion of the human motion complex (hMT+). MST changes were localized to the hemisphere contralateral to the region of the visual field, where perceptual training was delivered. Visual areas V2 and V3a showed an increase in activity between the first and second scan in the training group, but this was not correlated with performance. The contralateral anterior hippocampus and bilateral dorsolateral prefrontal cortex (DLPFC) and frontal pole showed changes in neural activity that also correlated with the amount of task learning. These findings emphasize the importance of MST in perceptual learning of a visual motion task. Hum Brain Mapp 39:145-156, 2018. © 2017 Wiley Periodicals, Inc. © 2017 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

  1. FORMATION AND ERUPTION OF A FLUX ROPE FROM THE SIGMOID ACTIVE REGION NOAA 11719 AND ASSOCIATED M6.5 FLARE: A MULTI-WAVELENGTH STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, Bhuwan; Kushwaha, Upendra; Dhara, Sajal Kumar [Udaipur Solar Observatory, Physical Research Laboratory, Udaipur 313001 (India); Veronig, Astrid M. [Kanzelhöhe Observatory/Institute of Physics, University of Graz, Universitätsplatz 5, A-8010 Graz (Austria); Shanmugaraju, A. [Department of Physics, Arul Anandhar College, Karumathur, Tamilnadu 625514 (India); Moon, Yong-Jae, E-mail: bhuwan@prl.res.in [School of Space Research, Kyung Hee University, Yongin, Gyeonggi-Do, 446-701 (Korea, Republic of)

    2017-01-01

    We investigate the formation, activation, and eruption of a flux rope (FR) from the sigmoid active region NOAA 11719 by analyzing E(UV), X-ray, and radio measurements. During the pre-eruption period of ∼7 hr, the AIA 94 Å images reveal the emergence of a coronal sigmoid through the interaction between two J-shaped bundles of loops, which proceeds with multiple episodes of coronal loop brightenings and significant variations in the magnetic flux through the photosphere. These observations imply that repetitive magnetic reconnections likely play a key role in the formation of the sigmoidal FR in the corona and also contribute toward sustaining the temperature of the FR higher than that of the ambient coronal structures. Notably, the formation of the sigmoid is associated with the fast morphological evolution of an S-shaped filament channel in the chromosphere. The sigmoid activates toward eruption with the ascent of a large FR in the corona, which is preceded by the decrease in photospheric magnetic flux through the core flaring region, suggesting tether-cutting reconnection as a possible triggering mechanism. The FR eruption results in a two-ribbon M6.5 flare with a prolonged rise phase of ∼21 minutes. The flare exhibits significant deviation from the standard flare model in the early rise phase, during which a pair of J-shaped flare ribbons form and apparently exhibit converging motions parallel to the polarity inversion line, which is further confirmed by the motions of hard X-ray footpoint sources. In the later stages, the flare follows the standard flare model and the source region undergoes a complete sigmoid-to-arcade transformation.

  2. Variation of radon flux along active fault zones in association with earthquake occurrence

    International Nuclear Information System (INIS)

    Papastefanou, C.

    2010-01-01

    Radon flux measurements were carried out at three radon stations along an active fault zone in the Langadas basin, Northern Greece by various techniques for earthquake prediction studies. Specially made devices with alpha track-etch detectors (ATDs) were installed by using LR-115, type II, non-strippable cellulose nitrate films (integrating method of measurements). Continuous monitoring of radon gas exhaling from the ground was also performed by using silicon diode detectors, Barasol and Clipperton type, in association with various probes and sensors including simultaneously registration of the meteorological parameters, such as precipitation height (rainfall events), temperature and barometric pressure. The obtained radon data were studied in parallel with the data of seismic events, such as the magnitude, M L of earthquakes, the epicentral distance, the hypocentral distance and the energy released during the earthquake event occurred at the fault zone during the period of measurements to find out any association between the rad on flux and the meteorological and seismological parameters. Seismic events with magnitude M L ≥ 4.0 appeared to be preceded by large precursory signals produced a well-defined 'anomaly' (peak) of radon flux prior to the event. In the results, the radon peaks in the obtained spectra appeared to be sharp and narrow. The rise time of a radon peak, that is the time period from the onset of a radon peak until the time of radon flux maximum is about a week, while the after time, that is the time interval between the time of radon flux maximum and the time of a seismic event ranges from about 3 weeks or more.

  3. Relationships between Microbial Activities and Subduction-related Outgassing and Volatile Flux at Aleutian Arc Volcanoes

    Science.gov (United States)

    Miller, H.; Lopez, T. M.; Fischer, T. P.; Schrenk, M. O.

    2016-12-01

    Subduction-related processes, including the movement and alteration of carbon compounds, are an important component of global geochemical cycles. Actively degassing volcanoes of the Aleutian Island arc offer interesting opportunities to not only characterize the composition and abundance of volatiles, but also to identify the origin of the discharging gases (e.g. mantle, organic matter, or carbonates). Taking this approach a step further, microbial activities in and around volcanic fumarole areas may impact the composition and flux of reduced volcanic gases, either through their modification or their assimilation into fixed biomass. Microbiological studies of these systems can be used to develop predictive models to complement those based upon geochemical data while providing greater understanding of the causal relationships between microbial populations and their environment, and ultimately refine estimates of volcanic outgassing. Coupled fumarole soil and gas samples were collected from several Aleutian Island volcanoes in 2015 (Gareloi, Kanaga, Kiska, Little Sitkin) and 2016 (Okmok, Resheschnoi). DNA was extracted from the soil and used to describe microbial community composition, while gas samples were analyzed through chromatography and mass spectrometry. Preliminary data suggests a relationship between the abundance of specific groups of prokaryotes known to metabolize reduced gases, such as sulfur-oxidizers and methanotrophs, and the abundances of the degassing volatiles, including sulfur dioxide and methane. Ongoing studies aimed at investigating the relationship between the genomic composition of the fumarolic microbial community and the physical and chemical properties of the soil (i.e. mineralogy, bulk geochemistry, nutrient concentration, gas flux, and environmental measurements) are underway. These data will be used to evaluate the potential for microbial communities to remove volcanic carbon and store it as biomass, or to modify the volatile carbon

  4. YANA – a software tool for analyzing flux modes, gene-expression and enzyme activities

    Directory of Open Access Journals (Sweden)

    Engels Bernd

    2005-06-01

    Full Text Available Abstract Background A number of algorithms for steady state analysis of metabolic networks have been developed over the years. Of these, Elementary Mode Analysis (EMA has proven especially useful. Despite its low user-friendliness, METATOOL as a reliable high-performance implementation of the algorithm has been the instrument of choice up to now. As reported here, the analysis of metabolic networks has been improved by an editor and analyzer of metabolic flux modes. Analysis routines for expression levels and the most central, well connected metabolites and their metabolic connections are of particular interest. Results YANA features a platform-independent, dedicated toolbox for metabolic networks with a graphical user interface to calculate (integrating METATOOL, edit (including support for the SBML format, visualize, centralize, and compare elementary flux modes. Further, YANA calculates expected flux distributions for a given Elementary Mode (EM activity pattern and vice versa. Moreover, a dissection algorithm, a centralization algorithm, and an average diameter routine can be used to simplify and analyze complex networks. Proteomics or gene expression data give a rough indication of some individual enzyme activities, whereas the complete flux distribution in the network is often not known. As such data are noisy, YANA features a fast evolutionary algorithm (EA for the prediction of EM activities with minimum error, including alerts for inconsistent experimental data. We offer the possibility to include further known constraints (e.g. growth constraints in the EA calculation process. The redox metabolism around glutathione reductase serves as an illustration example. All software and documentation are available for download at http://yana.bioapps.biozentrum.uni-wuerzburg.de. Conclusion A graphical toolbox and an editor for METATOOL as well as a series of additional routines for metabolic network analyses constitute a new user

  5. Mirror neuron activation of musicians and non-musicians in response to motion captured piano performances

    DEFF Research Database (Denmark)

    Hou, Jiancheng; Rajmohan, Ravi; Fang, Dan

    2017-01-01

    Mirror neurons (MNs) activate when performing an action and when an observer witnesses the same action performed by another individual. Functional magnetic resonance imaging (fMRI) and presentation of motion captured piano performances were used to identify differences in MN activation...... pronounced in the “Enjoyment” mode. Our findings suggest that activation of MNs is not only initiated by the imagined action of an observed movement, but such activation is modulated by the level of musical expertise and knowledge of associated motor movements that the observer brings to the viewing...

  6. Application of the IEAF-2001 activation data library to activation analyses of the IFMIF high flux test module

    International Nuclear Information System (INIS)

    Fischer, U.; Wilson, P.P.H.; Leichtle, D.; Simakov, S.P.; Moellendorff, U. von; Konobeev, A.; Korovin, Yu.; Pereslavtsev, P.; Schmuck, I.

    2002-01-01

    A complete activation data library IEAF-2001 (intermediate energy activation file) has been developed in standard ENDF-6 format with neutron-induced activation cross sections for 679 target nuclides from Z=1 (hydrogen) to Z=84 (polonium) and incident neutron energies up to 150 MeV. Using the NJOY processing code, an IEAF-2001 working library has been prepared in a 256 energy group structure for enabling activation analyses of the International Fusion Material Irradiation Facility (IFMIF) D-Li neutron source. This library was applied to the activation analysis of the IFMIF high flux test module using the recent Analytical and Laplacian Adaptive Radioactivity Analysis activation code which is capable of handling the variety of reaction channels open in the energy domain above 20 MeV. The IEAF-2001 activation library was thus shown to be suitable for activation analyses in fusion technology and intermediate energy applications such as the IFMIF D-Li neutron source

  7. High heat flux actively cooled plasma facing components development, realization and first results in Tore Supra

    International Nuclear Information System (INIS)

    Grosman, A.

    2004-01-01

    The development, design, manufacture and testing of actively cooled high heat flux plasma facing components (PFC) has been an essential stage towards long powerful tokamak operations for Tore-Supra, it lasted about 10 years. This paper deals with the toroidal pumped limiter (TPL) that is able to sustain up to 10 MW/m 2 of nominal heat flux. This device is based on hardened copper alloy heat sink structures covered by a carbon fiber composite armour, it resulted in the manufacturing of 600 elementary components, called finger elements, to achieve the 7.6 m 2 TPL. This assembly has been operating in Tore-Supra since spring 2002. Some difficulties occurred during the manufacturing phase, the valuable industrial experience is summarized in the section 2. The permanent monitoring of PFC surface temperature all along the discharge is performed by a set of 6 actively cooled infrared endoscopes. The heat flux monitoring and control issue but also the progress made in our understanding of the deuterium retention in long discharges are described in the section 3. (A.C.)

  8. High heat flux actively cooled plasma facing components development, realization and first results in Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Grosman, A. [Association Euratom-CEA, Centre d' Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee

    2004-07-01

    The development, design, manufacture and testing of actively cooled high heat flux plasma facing components (PFC) has been an essential stage towards long powerful tokamak operations for Tore-Supra, it lasted about 10 years. This paper deals with the toroidal pumped limiter (TPL) that is able to sustain up to 10 MW/m{sup 2} of nominal heat flux. This device is based on hardened copper alloy heat sink structures covered by a carbon fiber composite armour, it resulted in the manufacturing of 600 elementary components, called finger elements, to achieve the 7.6 m{sup 2} TPL. This assembly has been operating in Tore-Supra since spring 2002. Some difficulties occurred during the manufacturing phase, the valuable industrial experience is summarized in the section 2. The permanent monitoring of PFC surface temperature all along the discharge is performed by a set of 6 actively cooled infrared endoscopes. The heat flux monitoring and control issue but also the progress made in our understanding of the deuterium retention in long discharges are described in the section 3. (A.C.)

  9. Measure of thermal neutron flux in the IPEN/MB-01 reactor using 197 Au wire activation detectors

    International Nuclear Information System (INIS)

    Marques, Andre Luis Ferreira

    1995-01-01

    This dissertation has aimed at developing a neutron flux measurement technique by means of detectors activation analysis. The main task of this work was the implementation of this thermal neutron flux measurement technique, using gold wires as activation detectors in the IPEN/MB-01 reactor core. The neutron thermal flux spatial distribution was obtained by gold wire activation technique, with wire diameters of 0.125 mm and 0.250 mm in seven selected reactor experimental channels. The values of thermal flux were about 10 9 neutrons/cm 2 .s. This experiment has been the first one conducted with gold wires in the IPEN/MB-01 reactor, being this technique implemented for use by experiments in flux mapping of the core

  10. Analysis of traces at ORNL's new high-flux neutron activation laboratory

    International Nuclear Information System (INIS)

    Ricci, E.; Handley, T.H.; Dyer, F.F.

    1974-01-01

    The investigations are outlined, which are carried out in order to develop (preferably instrumental) methods for multielement analysis of various trace elements. For this reason a new High-Flux NAA Laboratory was constructed at ORNL's. A general review is given on the Laboratory, further some methods and applications are shown. In the field of comparator activation analysis comparative data are given on mercury determinations in various matrices, and on arsenic determination in grasshoppers. This later method was used to trace the transport of arsenic containing pesticides. Some data are given on absolute activation analysis of Na, Ci, Mn, Br, and Au, too. (K.A.)

  11. Thermal decomposition of solder flux activators under simulated wave soldering conditions

    DEFF Research Database (Denmark)

    Piotrowska, Kamila; Jellesen, Morten Stendahl; Ambat, Rajan

    2017-01-01

    /methodology/approach: Changes in the chemical structure of the activators were studied using Fourier transform infrared spectroscopy technique and were correlated to the exposure temperatures within the range of wave soldering process. The amount of residue left on the surface was estimated using standardized acid-base...... titration method as a function of temperature, time of exposure and the substrate material used. Findings: The study shows that there is a possibility of anhydride-like species formation during the thermal treatment of fluxes containing weak organic acids (WOAs) as activators (succinic and DL...

  12. Accounting for the thermal neutron flux depression in voluminous samples for instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Overwater, R.M.W.; Hoogenboom, J.E.

    1994-01-01

    At the Delft University of Technology Interfaculty Reactor Institute, a facility has been installed to irradiate cylindrical samples with diameters up to 15 cm and weights up to 50 kg for instrumental neutron activation analysis (INAA) purposes. To be able to do quantitative INAA on voluminous samples, it is necessary to correct for gamma-ray absorption, gamma-ray scattering, neutron absorption, and neutron scattering in the sample. The neutron absorption and the neutron scattering are discussed. An analytical solution is obtained for the diffusion equation in the geometry of the irradiation facility. For samples with known composition, the neutron flux--as a function of position in the sample--can be calculated directly. Those of unknown composition require additional flux measurements on which least-squares fitting must be done to obtain both the thermal neutron diffusion coefficient D s and the diffusion length L s of the sample. Experiments are performed to test the theory

  13. Active flux tungsten inert gas welding of austenitic stainless steel AISI 304

    Directory of Open Access Journals (Sweden)

    D. Klobčar

    2016-10-01

    Full Text Available The paper presents the effects of flux assisted tungsten inert gas (A-TIG welding of 4 (10 mm thick austenitic stainless steel EN X5CrNi1810 (AISI 304 in the butt joint. The sample dimensions were 300 ´ 50 mm, and commercially available active flux QuickTIG was used for testing. In the planned study the influence of welding position and weld groove shape was analysed based on the penetration depth. A comparison of microstructure formation, grain size and ferrit number between TIG welding and A-TIG welding was done. The A-TIG welds were subjected to bending test. A comparative study of TIG and A-TIG welding shows that A-TIG welding increases the weld penetration depth.

  14. Average energetic ion flux variations associated with geomagnetic activity from EPIC/STICS on Geotail

    Science.gov (United States)

    Christon, S. P.; Gloeckler, G.; Eastman, T. E.; McEntire, R. W.; Roelef, E. C.; Lui, A. T. Y.; Williams, D. J.; Frank, L. A.; Paterson, W. R.; Kokubun, S.; hide

    1996-01-01

    The magnetotail ion flux measurements from the Geotail spacecraft are analyzed both with and without the application of selection criteria that identify the plasma regime in which an observation is obtained. The different results are compared with each other. The initial results on the changes of energetic ion flux and composition correlated to average substorm activity in different magnetotail plasma regimes are discussed. The energetic ions are measured using the energetic particles and ion composition (EPIC) experiment and the suprathermal ion composition spectrometer (STICS). The plasma, wave and field instruments of the Geotail satellite were used to identify the principle magnetotail plasma regimes of plasma sheet, lobe, and magnetospheric boundary layer, as well as the magnetosheath and solar wind. Energetic O and H ions were observed in all the plasma regimes.

  15. Use of CITATION code for flux calculation in neutron activation analysis with voluminous sample using an Am-Be source

    International Nuclear Information System (INIS)

    Khelifi, R.; Idiri, Z.; Bode, P.

    2002-01-01

    The CITATION code based on neutron diffusion theory was used for flux calculations inside voluminous samples in prompt gamma activation analysis with an isotopic neutron source (Am-Be). The code uses specific parameters related to the energy spectrum source and irradiation system materials (shielding, reflector). The flux distribution (thermal and fast) was calculated in the three-dimensional geometry for the system: air, polyethylene and water cuboidal sample (50x50x50 cm). Thermal flux was calculated in a series of points inside the sample. The results agreed reasonably well with observed values. The maximum thermal flux was observed at a distance of 3.2 cm while CITATION gave 3.7 cm. Beyond a depth of 7.2 cm, the thermal flux to fast flux ratio increases up to twice and allows us to optimise the detection system position in the scope of in-situ PGAA

  16. Quasi-biennial modulation of solar neutrino flux: connections with solar activity

    Science.gov (United States)

    Vecchio, A.; Laurenza, M.; D'alessi, L.; Carbone, V.; Storini, M.

    2011-12-01

    A quasi-biennial periodicity has been recently found (Vecchio et al., 2010) in the solar neutrino flux, as detected at the Homestake experiment, as well as in the flux of solar energetic protons, by means of the Empirical Modes Decomposition technique. Moreover, both fluxes have been found to be significantly correlated at the quasi-biennial timescale, thus supporting the hypothesis of a connection between solar neutrinos and solar activity. The origin of this connection is investigated, by modeling how the standard Mikheyev-Smirnov-Wolfenstein (MSW) effect (the process for which the well-known neutrino flavor oscillations are modified in passing through the material) could be influenced by matter fluctuations. As proposed by Burgess et al., 2004, by introducing a background magnetic field in the helioseismic model, density fluctuations can be excited in the radiative zone by the resonance between helioseismic g-modes and Alfvén waves. In particular, with reasonable values of the background magnetic field (10-100 kG), the distance between resonant layers could be of the same order of neutrino oscillation length. We study the effect over this distance of a background magnetic field which is variable with a ~2 yr period, in agreement with typical variations of solar activity. Our findings suggest that the quasi-biennial modulation of the neutrino flux is theoretically possible as a consequence of the magnetic field variations in the solar interior. A. Vecchio, M. Laurenza, V. Carbone, M. Storini, The Astrophysical Journal Letters, 709, L1-L5 (2010). C. Burgess, N. S. Dzhalilov, T. I. Rashba, V., B.Semikoz, J. W. F. Valle, Mon. Not. R. Astron. Soc., 348, 609-624 (2004).

  17. Combination of Accumulated Motion and Color Segmentation for Human Activity Analysis

    Directory of Open Access Journals (Sweden)

    Briassouli Alexia

    2008-01-01

    Full Text Available Abstract The automated analysis of activity in digital multimedia, and especially video, is gaining more and more importance due to the evolution of higher-level video processing systems and the development of relevant applications such as surveillance and sports. This paper presents a novel algorithm for the recognition and classification of human activities, which employs motion and color characteristics in a complementary manner, so as to extract the most information from both sources, and overcome their individual limitations. The proposed method accumulates the flow estimates in a video, and extracts "regions of activity" by processing their higher-order statistics. The shape of these activity areas can be used for the classification of the human activities and events taking place in a video and the subsequent extraction of higher-level semantics. Color segmentation of the active and static areas of each video frame is performed to complement this information. The color layers in the activity and background areas are compared using the earth mover's distance, in order to achieve accurate object segmentation. Thus, unlike much existing work on human activity analysis, the proposed approach is based on general color and motion processing methods, and not on specific models of the human body and its kinematics. The combined use of color and motion information increases the method robustness to illumination variations and measurement noise. Consequently, the proposed approach can lead to higher-level information about human activities, but its applicability is not limited to specific human actions. We present experiments with various real video sequences, from sports and surveillance domains, to demonstrate the effectiveness of our approach.

  18. Combination of Accumulated Motion and Color Segmentation for Human Activity Analysis

    Directory of Open Access Journals (Sweden)

    Ioannis Kompatsiaris

    2008-03-01

    Full Text Available The automated analysis of activity in digital multimedia, and especially video, is gaining more and more importance due to the evolution of higher-level video processing systems and the development of relevant applications such as surveillance and sports. This paper presents a novel algorithm for the recognition and classification of human activities, which employs motion and color characteristics in a complementary manner, so as to extract the most information from both sources, and overcome their individual limitations. The proposed method accumulates the flow estimates in a video, and extracts “regions of activity” by processing their higher-order statistics. The shape of these activity areas can be used for the classification of the human activities and events taking place in a video and the subsequent extraction of higher-level semantics. Color segmentation of the active and static areas of each video frame is performed to complement this information. The color layers in the activity and background areas are compared using the earth mover's distance, in order to achieve accurate object segmentation. Thus, unlike much existing work on human activity analysis, the proposed approach is based on general color and motion processing methods, and not on specific models of the human body and its kinematics. The combined use of color and motion information increases the method robustness to illumination variations and measurement noise. Consequently, the proposed approach can lead to higher-level information about human activities, but its applicability is not limited to specific human actions. We present experiments with various real video sequences, from sports and surveillance domains, to demonstrate the effectiveness of our approach.

  19. Uncertainties in measuring trace amounts of cobalt and europium with low-flux neutron activation analysis

    Directory of Open Access Journals (Sweden)

    Burnham Steven

    2017-01-01

    Full Text Available Neutron activation analysis is widely used for identification of elements and their quantities even in trace amounts in the samples of almost any type. The challenges in detecting trace amounts of particular elements are often associated with the neutron flux produced at the research reactors. Low-flux neutron activation analysis usually presents the biggest challenge when analyzing trace quantities of elements with lower magnitude of radiative capture cross-sections. In this paper, we present the methodology and the quantified uncertainties associated with the detection of trace amounts of cobalt and europium, using as an example concrete aggregates. Recent growing interest is in improving structural concrete (increasing its strength but reducing its activation in nuclear power plant environments. Aside from buildings, structural concrete is also used as a biological shield in nuclear power plant that become radioactive after exposure to neutron flux. Due to radiative capture interactions, artificial radionuclides are generated to high enough concentrations that classify concrete as low-level radioactive waste at the time of the plant's decommissioning. Disposal of this concrete adds to the expense of nuclear power plant financing and its construction. Three radionuclides, 60Co, 152Eu, and 154Eu, account for 99 % of total residual radioactivity of nuclear power plant decommissioned concrete. IAEA document RS-G-1.7, Application of the Concepts of Exclusion, Exemption, and Clearance, specifies clearance levels of radionuclides specific activities: a specific activity lower than 0.1 Bqg-1 for 60Co and 152Eu, and 154Eu allows for a concrete to be recycled after decommissioning of the nuclear power plant. Therefore, low-flux neutron activation analysis is used to test the detection limits of trace elements in samples of cement, coarse, and fine concrete aggregates. These samples are irradiated at the University of Utah's 100 kW TRIGA Reactor at

  20. The use of active breathing control (ABC) to reduce margin for breathing motion

    International Nuclear Information System (INIS)

    Wong, John W.; Sharpe, Michael B.; Jaffray, David A.; Kini, Vijay R.; Robertson, John M.; Stromberg, Jannifer S.; Martinez, Alavro A.

    1999-01-01

    Purpose: For tumors in the thorax and abdomen, reducing the treatment margin for organ motion due to breathing reduces the volume of normal tissues that will be irradiated. A higher dose can be delivered to the target, provided that the risk of marginal misses is not increased. To ensure safe margin reduction, we investigated the feasibility of using active breathing control (ABC) to temporarily immobilize the patient's breathing. Treatment planning and delivery can then be performed at identical ABC conditions with minimal margin for breathing motion. Methods and Materials: An ABC apparatus is constructed consisting of 2 pairs of flow monitor and scissor valve, 1 each to control the inspiration and expiration paths to the patient. The patient breathes through a mouth-piece connected to the ABC apparatus. The respiratory signal is processed continuously, using a personal computer that displays the changing lung volume in real-time. After the patient's breathing pattern becomes stable, the operator activates ABC at a preselected phase in the breathing cycle. Both valves are then closed to immobilize breathing motion. Breathing motion of 12 patients were held with ABC to examine their acceptance of the procedure. The feasibility of applying ABC for treatment was tested in 5 patients by acquiring volumetric scans with a spiral computed tomography (CT) scanner during active breath-hold. Two patients had Hodgkin's disease, 2 had metastatic liver cancer, and 1 had lung cancer. Two intrafraction ABC scans were acquired at the same respiratory phase near the end of normal or deep inspiration. An additional ABC scan near the end of normal expiration was acquired for 2 patients. The ABC scans were also repeated 1 week later for a Hodgkin's patient. In 1 liver patient, ABC scans were acquired at 7 different phases of the breathing cycle to facilitate examination of the liver motion associated with ventilation. Contours of the lungs and livers were outlined when applicable

  1. Activity and Kinematics of White Dwarf-M Dwarf Binaries from the SUPERBLINK Proper Motion Survey

    Science.gov (United States)

    Skinner, Julie N.; Morgan, Dylan P.; West, Andrew A.; Lépine, Sébastien; Thorstensen, John R.

    2017-09-01

    We present an activity and kinematic analysis of high proper motion white dwarf-M dwarf binaries (WD+dMs) found in the SUPERBLINK survey, 178 of which are new identifications. To identify WD+dMs, we developed a UV-optical-IR color criterion and conducted a spectroscopic survey to confirm each candidate binary. For the newly identified systems, we fit the two components using model white dwarf spectra and M dwarf template spectra to determine physical parameters. We use Hα chromospheric emission to examine the magnetic activity of the M dwarf in each system, and investigate how its activity is affected by the presence of a white dwarf companion. We find that the fraction of WD+dM binaries with active M dwarfs is significantly higher than their single M dwarf counterparts at early and mid-spectral types. We corroborate previous studies that find high activity fractions at both close and intermediate separations. At more distant separations, the binary fraction appears to approach the activity fraction for single M dwarfs. Using derived radial velocities and the proper motions, we calculate 3D space velocities for the WD+dMs in SUPERBLINK. For the entire SUPERBLINK WD+dMs, we find a large vertical velocity dispersion, indicating a dynamically hotter population compared to high proper motion samples of single M dwarfs. We compare the kinematics for systems with active M dwarfs and those with inactive M dwarfs, and find signatures of asymmetric drift in the inactive sample, indicating that they are drawn from an older population. Based on observations obtained at the MDM Observatory operated by Dartmouth College, Columbia University, The Ohio State University, and the University of Michigan.

  2. Activity and Kinematics of White Dwarf-M Dwarf Binaries from the SUPERBLINK Proper Motion Survey

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, Julie N. [Institute for Astrophysical Research, Boston University, 725 Commonwealth Avenue, Boston, MA 02215 (United States); Morgan, Dylan P.; West, Andrew A. [Department of Astronomy, Boston University, 725 Commonwealth Avenue, Boston, MA 02215 (United States); Lépine, Sébastien [Department of Physics and Astronomy, Georgia State University, 25 Park Place NE, Atlanta, GA, 30303 (United States); Thorstensen, John R., E-mail: jskinner@bu.edu [Department of Physics and Astronomy, 6127 Wilder Laboratory, Dartmouth College, Hanover, NH 03755 (United States)

    2017-09-01

    We present an activity and kinematic analysis of high proper motion white dwarf-M dwarf binaries (WD+dMs) found in the SUPERBLINK survey, 178 of which are new identifications. To identify WD+dMs, we developed a UV–optical–IR color criterion and conducted a spectroscopic survey to confirm each candidate binary. For the newly identified systems, we fit the two components using model white dwarf spectra and M dwarf template spectra to determine physical parameters. We use H α chromospheric emission to examine the magnetic activity of the M dwarf in each system, and investigate how its activity is affected by the presence of a white dwarf companion. We find that the fraction of WD+dM binaries with active M dwarfs is significantly higher than their single M dwarf counterparts at early and mid-spectral types. We corroborate previous studies that find high activity fractions at both close and intermediate separations. At more distant separations, the binary fraction appears to approach the activity fraction for single M dwarfs. Using derived radial velocities and the proper motions, we calculate 3D space velocities for the WD+dMs in SUPERBLINK. For the entire SUPERBLINK WD+dMs, we find a large vertical velocity dispersion, indicating a dynamically hotter population compared to high proper motion samples of single M dwarfs. We compare the kinematics for systems with active M dwarfs and those with inactive M dwarfs, and find signatures of asymmetric drift in the inactive sample, indicating that they are drawn from an older population.

  3. Activity and Kinematics of White Dwarf-M Dwarf Binaries from the SUPERBLINK Proper Motion Survey

    International Nuclear Information System (INIS)

    Skinner, Julie N.; Morgan, Dylan P.; West, Andrew A.; Lépine, Sébastien; Thorstensen, John R.

    2017-01-01

    We present an activity and kinematic analysis of high proper motion white dwarf-M dwarf binaries (WD+dMs) found in the SUPERBLINK survey, 178 of which are new identifications. To identify WD+dMs, we developed a UV–optical–IR color criterion and conducted a spectroscopic survey to confirm each candidate binary. For the newly identified systems, we fit the two components using model white dwarf spectra and M dwarf template spectra to determine physical parameters. We use H α chromospheric emission to examine the magnetic activity of the M dwarf in each system, and investigate how its activity is affected by the presence of a white dwarf companion. We find that the fraction of WD+dM binaries with active M dwarfs is significantly higher than their single M dwarf counterparts at early and mid-spectral types. We corroborate previous studies that find high activity fractions at both close and intermediate separations. At more distant separations, the binary fraction appears to approach the activity fraction for single M dwarfs. Using derived radial velocities and the proper motions, we calculate 3D space velocities for the WD+dMs in SUPERBLINK. For the entire SUPERBLINK WD+dMs, we find a large vertical velocity dispersion, indicating a dynamically hotter population compared to high proper motion samples of single M dwarfs. We compare the kinematics for systems with active M dwarfs and those with inactive M dwarfs, and find signatures of asymmetric drift in the inactive sample, indicating that they are drawn from an older population.

  4. Neutron flux measurements at the TRIGA reactor in Vienna for the prediction of the activation of the biological shield

    International Nuclear Information System (INIS)

    Merz, Stefan; Djuricic, Mile; Villa, Mario; Boeck, Helmuth; Steinhauser, Georg

    2011-01-01

    The activation of the biological shield is an important process for waste management considerations of nuclear facilities. The final activity can be estimated by modeling using the neutron flux density rather than the radiometric approach of activity measurements. Measurement series at the TRIGA reactor Vienna reveal that the flux density next to the biological shield is in the order of 10 9 cm -2 s -1 at maximum power; but it is strongly influenced by reactor installations. The data allow the estimation of the final waste categorization of the concrete according to the Austrian legislation. - Highlights: → Neutron activation is an important process for the waste management of nuclear facilities. → Biological shield of the TRIGA reactor Vienna has been topic of investigation. → Flux values allow a categorization of the concrete concerning radiation protection legislation. → Reactor installations are of great importance as neutron sources into the biological shield. → Every installation shows distinguishable flux profiles.

  5. Theoretical Insights Reveal Novel Motions in Csk's SH3 Domain That Control Kinase Activation.

    Directory of Open Access Journals (Sweden)

    Sulyman Barkho

    Full Text Available The Src family of tyrosine kinases (SFKs regulate numerous aspects of cell growth and differentiation and are under the principal control of the C-terminal Src Kinase (Csk. Although Csk and SFKs share conserved kinase, SH2 and SH3 domains, they differ considerably in three-dimensional structure, regulatory mechanism, and the intrinsic kinase activities. Although the SH2 and SH3 domains are known to up- or down-regulate tyrosine kinase function, little is known about the global motions in the full-length kinase that govern these catalytic variations. We use a combination of accelerated Molecular Dynamics (aMD simulations and experimental methods to provide a new view of functional motions in the Csk scaffold. These computational studies suggest that high frequency vibrations in the SH2 domain are coupled through the N-terminal lobe of the kinase domain to motions in the SH3 domain. The effects of these reflexive movements on the kinase domain can be viewed using both Deuterium Exchange Mass Spectrometry (DXMS and steady-state kinetic methods. Removal of several contacts, including a crystallographically unobserved N-terminal segment, between the SH3 and kinase domains short-circuit these coupled motions leading to reduced catalytic efficiency and stability of N-lobe motifs within the kinase domain. The data expands the model of Csk's activation whereby separate domains productively interact with two diametrically opposed surfaces of the kinase domain. Such reversible transitions may organize the active structure of the tyrosine kinase domain of Csk.

  6. On the area expansion of magnetic flux tubes in solar active regions

    Energy Technology Data Exchange (ETDEWEB)

    Dudík, Jaroslav [DAMTP, CMS, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom); Dzifčáková, Elena [Astronomical Institute of the Academy of Sciences of the Czech Republic, Fričova 298, 251 65 Ondřejov (Czech Republic); Cirtain, Jonathan W., E-mail: J.Dudik@damtp.cam.ac.uk, E-mail: elena@asu.cas.cz [NASA Marshall Space Flight Center, VP 62, Huntsville, AL 35812 (United States)

    2014-11-20

    We calculated the three-dimensional (3D) distribution of the area expansion factors in a potential magnetic field, extrapolated from the high-resolution Hinode/SOT magnetogram of the quiescent active region NOAA 11482. Retaining only closed loops within the computational box, we show that the distribution of area expansion factors show significant structure. Loop-like structures characterized by locally lower values of the expansion factor are embedded in a smooth background. These loop-like flux tubes have squashed cross-sections and expand with height. The distribution of the expansion factors show an overall increase with height, allowing an active region core characterized by low values of the expansion factor to be distinguished. The area expansion factors obtained from extrapolation of the Solar Optical Telescope magnetogram are compared to those obtained from an approximation of the observed magnetogram by a series of 134 submerged charges. This approximation retains the general flux distribution in the observed magnetogram, but removes the small-scale structure in both the approximated magnetogram and the 3D distribution of the area expansion factors. We argue that the structuring of the expansion factor can be a significant ingredient in producing the observed structuring of the solar corona. However, due to the potential approximation used, these results may not be applicable to loops exhibiting twist or to active regions producing significant flares.

  7. Some analyses on the plasma motion in the space active region of the axial symmetry

    International Nuclear Information System (INIS)

    Li Zhongyuan; Hu Wenrui.

    1986-04-01

    In general, the potential magnetic field may gradually be twisted into the force-free magnetic field with the current produced by plasma rotation. In this paper, it is pointed out that if the magnetic field has no singularity on the symmetric axis, then the potential magnetic field cannot be twisted into the force-free magnetic field. Namely, it is not a perfect approach that the energy storage is only caused by the pure azimuthal motion in the active region. Besides the pure spiral motion, the unsteady coupling process between the magnetic field and both the toroidal and the poloidal velocity components should be analyzed. Finally, in the present note, some features of the kinematical force-free magnetic field of the axial symmetry are presented by the authors. (author)

  8. Relationship between massive chronic rotator cuff tear pattern and loss of active shoulder range of motion.

    Science.gov (United States)

    Collin, Philippe; Matsumura, Noboru; Lädermann, Alexandre; Denard, Patrick J; Walch, Gilles

    2014-08-01

    Management of massive chronic rotator cuff tears remains controversial, with no clearly defined clinical presentation as yet. The purpose of the study was to evaluate the effect of tear size and location on active motion in patients with chronic and massive rotator cuff tears with severe muscle degeneration. One hundred patients with massive rotator cuff tears accompanied by muscle fatty infiltration beyond Goutallier stage 3 were prospectively included in this study. All patients were divided into 5 groups on the basis of tear pattern (supraspinatus, superior subscapularis, inferior subscapularis, infraspinatus, and teres minor). Active range of shoulder motion was assessed in each group and differences were analyzed. Active elevation was significantly decreased in patients with 3 tear patterns involved. Pseudoparalysis was found in 80% of the cases with supraspinatus and complete subscapularis tears and in 45% of the cases with tears involving the supraspinatus, infraspinatus, and superior subscapularis. Loss of active external rotation was related to tears involving the infraspinatus and teres minor; loss of active internal rotation was related to tears of the subscapularis. This study revealed that dysfunction of the entire subscapularis and supraspinatus or 3 rotator cuff muscles is a risk factor for pseudoparalysis. For function to be preserved in patients with massive chronic rotator cuff tears, it may be important to avoid fatty infiltration with anterior extension into the lower subscapularis or involvement of more than 2 rotator cuff muscles. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

  9. Activation of retinal glial (Müller cells by extracellular ATP induces pronounced increases in extracellular H+ flux.

    Directory of Open Access Journals (Sweden)

    Boriana K Tchernookova

    Full Text Available Small alterations in extracellular acidity are potentially important modulators of neuronal signaling within the vertebrate retina. Here we report a novel extracellular acidification mechanism mediated by glial cells in the retina. Using self-referencing H+-selective microelectrodes to measure extracellular H+ fluxes, we show that activation of retinal Müller (glial cells of the tiger salamander by micromolar concentrations of extracellular ATP induces a pronounced extracellular H+ flux independent of bicarbonate transport. ADP, UTP and the non-hydrolyzable analog ATPγs at micromolar concentrations were also potent stimulators of extracellular H+ fluxes, but adenosine was not. The extracellular H+ fluxes induced by ATP were mimicked by the P2Y1 agonist MRS 2365 and were significantly reduced by the P2 receptor blockers suramin and PPADS, suggesting activation of P2Y receptors. Bath-applied ATP induced an intracellular rise in calcium in Müller cells; both the calcium rise and the extracellular H+ fluxes were significantly attenuated when calcium re-loading into the endoplasmic reticulum was inhibited by thapsigargin and when the PLC-IP3 signaling pathway was disrupted with 2-APB and U73122. The anion transport inhibitor DIDS also markedly reduced the ATP-induced increase in H+ flux while SITS had no effect. ATP-induced H+ fluxes were also observed from Müller cells isolated from human, rat, monkey, skate and lamprey retinae, suggesting a highly evolutionarily conserved mechanism of potential general importance. Extracellular ATP also induced significant increases in extracellular H+ flux at the level of both the outer and inner plexiform layers in retinal slices of tiger salamander which was significantly reduced by suramin and PPADS. We suggest that the novel H+ flux mediated by ATP-activation of Müller cells and of other glia as well may be a key mechanism modulating neuronal signaling in the vertebrate retina and throughout the brain.

  10. Robotic Assistance of Human Motion Using Active-Backdrivability on a Geared Electromagnetic Motor

    Directory of Open Access Journals (Sweden)

    Mario Jorge Claros

    2016-03-01

    Full Text Available In this research, we describe an actuation and control system designed for geared electromagnetic motors, which is characterized by its simple implementation, fast response to external input loads, reliable human-machine interaction features, no need for previous set-up or calibration from user to user and high portability due to the reduction of weight and space used. By the implementation of the proposed system, an electromagnetic motor can become a multitasking, wearable actuation system capable of: detecting the user's intentions regarding motion, tracking the limbs with minimal force interaction within a wide bandwidth and also providing controllable assistance and resistance forces to the user's movements, without the use of any biological signal. Validation of the proposed approach is shown by the construction of a powered orthosis for the knee, used to test the system's performance under real human motion conditions. The proposed system was tested on one healthy subject by measuring electromyographic levels both with and without the orthosis, under controlled flexion and extension cycles. Experimental results demonstrate the effectiveness of the proposed approach in detecting the user's intentions regarding motion, reducing and increasing muscular activity when configured for assistance and resistance, respectively, and also increasing the transparency of the actuation system when perfect tracking of the limbs is needed.

  11. A unified internal model theory to resolve the paradox of active versus passive self-motion sensation.

    Science.gov (United States)

    Laurens, Jean; Angelaki, Dora E

    2017-10-18

    Brainstem and cerebellar neurons implement an internal model to accurately estimate self-motion during externally generated ('passive') movements. However, these neurons show reduced responses during self-generated ('active') movements, indicating that predicted sensory consequences of motor commands cancel sensory signals. Remarkably, the computational processes underlying sensory prediction during active motion and their relationship to internal model computations during passive movements remain unknown. We construct a Kalman filter that incorporates motor commands into a previously established model of optimal passive self-motion estimation. The simulated sensory error and feedback signals match experimentally measured neuronal responses during active and passive head and trunk rotations and translations. We conclude that a single sensory internal model can combine motor commands with vestibular and proprioceptive signals optimally. Thus, although neurons carrying sensory prediction error or feedback signals show attenuated modulation, the sensory cues and internal model are both engaged and critically important for accurate self-motion estimation during active head movements.

  12. Development of Kinematic Graphs of Median Nerve during Active Finger Motion: Implications of Smartphone Use.

    Directory of Open Access Journals (Sweden)

    Hoi-Chi Woo

    Full Text Available Certain hand activities cause deformation and displacement of the median nerve at the carpal tunnel due to the gliding motion of tendons surrounding it. As smartphone usage escalates, this raises the public's concern whether hand activities while using smartphones can lead to median nerve problems.The aims of this study were to 1 develop kinematic graphs and 2 investigate the associated deformation and rotational information of median nerve in the carpal tunnel during hand activities.Dominant wrists of 30 young adults were examined with ultrasonography by placing a transducer transversely on their wrist crease. Ultrasound video clips were recorded when the subject performing 1 thumb opposition with the wrist in neutral position, 2 thumb opposition with the wrist in ulnar deviation and 3 pinch grip with the wrist in neutral position. Six still images that were separated by 0.2-second intervals were then captured from the ultrasound video for the determination of 1 cross-sectional area (CSA, 2 flattening ratio (FR, 3 rotational displacement (RD and 4 translational displacement (TD of median nerve in the carpal tunnel, and these collected information of deformation, rotational and displacement of median nerve were compared between 1 two successive time points during a single hand activity and 2 different hand motions at the same time point. Finally, kinematic graphs were constructed to demonstrate the mobility of median nerve during different hand activities.Performing different hand activities during this study led to a gradual reduction in CSA of the median nerve, with thumb opposition together with the wrist in ulnar deviation causing the greatest extent of deformation of the median nerve. Thumb opposition with the wrist in ulnar deviation also led to the largest extent of TD when compared to the other two hand activities of this study. Kinematic graphs showed that the motion pathways of median nerve during different hand activities were complex

  13. Effect of Ca doping on thermally activated flux flow in the ...

    Indian Academy of Sciences (India)

    Administrator

    attracted much attention.10,11 Resistivity measurements under magnetic fields ... The flux line dynamics can be divided into three regimes (i) flux flow, J > Jc; .... energy dissipation occurs when the driving Lorentz force is increased with the ...

  14. Relationships between Paraspinal Muscle Activity and Lumbar Inter-Vertebral Range of Motion

    Directory of Open Access Journals (Sweden)

    Alister du Rose

    2016-01-01

    Full Text Available Control of the lumbar spine requires contributions from both the active and passive sub-systems. Identifying interactions between these systems may provide insight into the mechanisms of low back pain. However, as a first step it is important to investigate what is normal. The purpose of this study was to explore the relationships between the lumbar inter-vertebral range of motion and paraspinal muscle activity during weight-bearing flexion in healthy controls using quantitative fluoroscopy (QF and surface electromyography (sEMG. Contemporaneous lumbar sEMG and QF motion sequences were recorded during controlled active flexion of 60° using electrodes placed over Longissimus thoracis pars thoracis (TES, Longissimus thoracis pars lumborum (LES, and Multifidus (LMU. Normalised root mean square (RMS sEMG amplitude data were averaged over five epochs, and the change in amplitude between epochs was calculated. The sEMG ratios of LMU/LES LMU/TES and LES/TES were also determined. QF was used to measure the maximum inter-vertebral range of motion from L2-S1, and correlation coefficients were calculated between sEMG amplitude variables and these measurements. Intra- and inter-session sEMG amplitude repeatability was also assessed for all three paraspinal muscles. The sEMG amplitude measurements were highly repeatable, and sEMG amplitude changes correlated significantly with L4-5 and L5-S1 IV-RoMmax (r = −0.47 to 0.59. The sEMG amplitude ratio of LES/TES also correlated with L4-L5 IV-RoMmax (r = −0.53. The relationships found may be important when considering rehabilitation for low back pain.

  15. Relationships between Paraspinal Muscle Activity and Lumbar Inter-Vertebral Range of Motion.

    Science.gov (United States)

    du Rose, Alister; Breen, Alan

    2016-01-05

    Control of the lumbar spine requires contributions from both the active and passive sub-systems. Identifying interactions between these systems may provide insight into the mechanisms of low back pain. However, as a first step it is important to investigate what is normal. The purpose of this study was to explore the relationships between the lumbar inter-vertebral range of motion and paraspinal muscle activity during weight-bearing flexion in healthy controls using quantitative fluoroscopy (QF) and surface electromyography (sEMG). Contemporaneous lumbar sEMG and QF motion sequences were recorded during controlled active flexion of 60° using electrodes placed over Longissimus thoracis pars thoracis (TES), Longissimus thoracis pars lumborum (LES), and Multifidus (LMU). Normalised root mean square (RMS) sEMG amplitude data were averaged over five epochs, and the change in amplitude between epochs was calculated. The sEMG ratios of LMU/LES LMU/TES and LES/TES were also determined. QF was used to measure the maximum inter-vertebral range of motion from L2-S1, and correlation coefficients were calculated between sEMG amplitude variables and these measurements. Intra- and inter-session sEMG amplitude repeatability was also assessed for all three paraspinal muscles. The sEMG amplitude measurements were highly repeatable, and sEMG amplitude changes correlated significantly with L4-5 and L5-S1 IV-RoMmax (r = -0.47 to 0.59). The sEMG amplitude ratio of LES/TES also correlated with L4-L5 IV-RoMmax (r = -0.53). The relationships found may be important when considering rehabilitation for low back pain.

  16. Radiographic x-ray flux monitoring during explosive experiments by copper activation

    International Nuclear Information System (INIS)

    Goosman, D.R.

    1986-01-01

    During radiographic experiments involving explosives, it is valuable to have a method of monitoring the X-ray flux ratio between the dynamic experiment and an X-ray taken of a static object for comparison. The standard method of monitoring with thermoluminescent detectors suffers the disadvantages of being sensitive to temperature, shock, UV radiation, cleanliness and saturation. We are studying an additional flux monitoring system which is not subject to any of the above disadvantages and is based upon the 63 Cu(photon,n) 62 Cu reaction. The 62 Cu has a 10 min. half-life and is counted by a nuclear pulse-counting system within a few minutes of an explosive test. 170 MicroCoulomb of 19.3 MeV electrons hitting 1.18mm of Ta produces X-rays which illuminate a 0.8mm thick by 1.6cm diameter Cu disk placed 46cm from the Ta. The activated Cu is placed in a counting system with a window between 400-600 keV and produces about 42500 counts in the first 100 sec counting period. Less than 0.2% of the initial activity is due to other reactions. Photo-induced neutrons in Be parts of the system are shown to produce a negligible effect in the Cu. The main disadvantage of the Cu activation is its sensitivity to electron energy. Monte-Carlo calculations of the excitation function for our accelerator are shown, along with excitation functions for three other configurations

  17. Radiographic x-ray flux monitoring during explosive experiments by copper activation

    International Nuclear Information System (INIS)

    Goosman, D.R.

    1986-01-01

    During radiographic experiments involving explosives, it is valuable to have a method of monitoring the x-ray flux ratio between the dynamic experiment and an x-ray taken of a static object for comparison. The standard method of monitoring with thermoluminescent detectors suffers the disadvantages of being sensitive to temperature, shock, uv radiation, cleanliness and saturation. A flux monitoring system is being studied which is not subject to any of the above disadvantages and is based upon the 63Cu(photon,n)62Cu reaction. The 62Cu has a 10 min half life and is counted by a nuclear pulse counting system within a few minutes of an explosive test. 170 microcoulomb of 19.3 MeV electrons hitting 1.18 mm of Ta produces x-rays which illuminate a 0.8mm thick by 1.6 cm diameter Cu disk placed 46 cm from the Ta. The activated Cu is placed in a counting system with a window between 400 to 600 keV and produces about 42,500 counts in the first 100 sec. counting period. Less than 0.2% of the initial activity is due to other reactions. Photo-induced neutrons in Be parts of the system are shown to produce a negligible effect in the Cu. The main disadvantage of the Cu activation is its sensitivity to electron energy. Monte-Carlo calculations of the excitation function for our accelerator are shown, along with excitation functions for three other configurations

  18. Extract the Relational Information of Static Features and Motion Features for Human Activities Recognition in Videos

    Directory of Open Access Journals (Sweden)

    Li Yao

    2016-01-01

    Full Text Available Both static features and motion features have shown promising performance in human activities recognition task. However, the information included in these features is insufficient for complex human activities. In this paper, we propose extracting relational information of static features and motion features for human activities recognition. The videos are represented by a classical Bag-of-Word (BoW model which is useful in many works. To get a compact and discriminative codebook with small dimension, we employ the divisive algorithm based on KL-divergence to reconstruct the codebook. After that, to further capture strong relational information, we construct a bipartite graph to model the relationship between words of different feature set. Then we use a k-way partition to create a new codebook in which similar words are getting together. With this new codebook, videos can be represented by a new BoW vector with strong relational information. Moreover, we propose a method to compute new clusters from the divisive algorithm’s projective function. We test our work on the several datasets and obtain very promising results.

  19. Effects of high-frequency activity on latent heat flux of MJO

    Science.gov (United States)

    Gao, Yingxia; Hsu, Pang-Chi; Li, Tim

    2018-04-01

    The effect of high-frequency (HF) variability on latent heat flux (LHF) associated with the Madden-Julian Oscillation (MJO) during the boreal winter is investigated through diagnosis using two reanalysis datasets and numerical experiments of an atmospheric general circulation model (AGCM). The diagnostic results show that the HF activities exert an impact on the variability of MJO LHF mainly through their interactions with the longer than 90-day low-frequency background state (LFBS). The contribution of intraseasonal LHF induced by the interactions between LFBS and HF activities accounts for more than 20% of the total intraseasonal LHF over active MJO regions. The intraseasonal LHF induced by the LFBS-HF interaction is in phase with the MJO convection, while the total intraseasonal LHF appears at and to the west of the MJO convection center. This suggests that the intraseasonal LHF via the feedback of HF activity interacting with LFBS is conducive to the maintenance and eastward propagation of MJO convection. To confirm the role of HF disturbances in MJO convection activity, we carry out a series of experiments using the AGCM of ECHAM4, which captures well the general features of MJO. We select a number of MJO cases with enhanced convective signals and significant eastward propagation from a 30-year climatological simulation. Once the HF components of surface wind and moisture fields in LHF are excluded in model integration for each MJO case, most of the simulated MJO convection shows weakened activity and a slower propagation speed compared to the simulations containing all time-scale components. The outputs of these sensitivity experiments support the diagnostic results that HF activities contribute to the maintenance and propagation of MJO convection through the intraseasonal LHF induced by the scale interaction of HF activities with lower frequency variability.

  20. Design of an actively cooled plate calorimeter for the investigation of pool fire heat fluxes

    International Nuclear Information System (INIS)

    Koski, J.A.; Keltner, N.R.; Nicolette, V.F.; Wix, S.D.

    1993-01-01

    In order to better measure local heat fluxes in open pool fires, an actively cooled calorimeter has been designed and analyzed. As this paper is being prepared, the calorimeter is in fabrication. Following fabrication, testing in a radiant heat facility is planned to assure proper performance before introduction into the pool fire environment. Initially, testing in the SMERF facility will assure reproducibility of tests by removing wind effects. As the program progresses, tests in open facilities, and with different geometries are anticipated. Experimental data from the initial tests will be compared continuously to the gray gas model, and as experiments proceed, the gray gas analytical model will be refined with the goal of improving finite element code analysis of shipping containers. (J.P.N.)

  1. Flux balance modeling to predict bacterial survival during pulsed-activity events

    Science.gov (United States)

    Jose, Nicholas A.; Lau, Rebecca; Swenson, Tami L.; Klitgord, Niels; Garcia-Pichel, Ferran; Bowen, Benjamin P.; Baran, Richard; Northen, Trent R.

    2018-04-01

    Desert biological soil crusts (BSCs) are cyanobacteria-dominated surface soil microbial communities common to plant interspaces in arid environments. The capability to significantly dampen their metabolism allows them to exist for extended periods in a desiccated dormant state that is highly robust to environmental stresses. However, within minutes of wetting, metabolic functions reboot, maximizing activity during infrequent permissive periods. Microcoleus vaginatus, a primary producer within the crust ecosystem and an early colonizer, initiates crust formation by binding particles in the upper layer of soil via exopolysaccharides, making microbial dominated biological soil crusts highly dependent on the viability of this organism. Previous studies have suggested that biopolymers play a central role in the survival of this organism by powering resuscitation, rapidly forming compatible solutes, and fueling metabolic activity in dark, hydrated conditions. To elucidate the mechanism of this phenomenon and provide a basis for future modeling of BSCs, we developed a manually curated, genome-scale metabolic model of Microcoleus vaginatus (iNJ1153). To validate this model, gas chromatography-mass spectroscopy (GC-MS) and liquid chromatography-mass spectroscopy (LC-MS) were used to characterize the rate of biopolymer accumulation and depletion in in hydrated Microcoleus vaginatus under light and dark conditions. Constraint-based flux balance analysis showed agreement between model predictions and experimental reaction fluxes. A significant amount of consumed carbon and light energy is invested into storage molecules glycogen and polyphosphate, while β-polyhydroxybutyrate may function as a secondary resource. Pseudo-steady-state modeling suggests that glycogen, the primary carbon source with the fastest depletion rate, will be exhausted if M. vaginatus experiences dark wetting events 4 times longer than light wetting events.

  2. Atypical activation of the mirror neuron system during perception of hand motion in autism.

    Science.gov (United States)

    Martineau, Joëlle; Andersson, Frédéric; Barthélémy, Catherine; Cottier, Jean-Philippe; Destrieux, Christophe

    2010-03-12

    Disorders in the autism spectrum are characterized by deficits in social and communication skills such as imitation, pragmatic language, theory of mind, and empathy. The discovery of the "mirror neuron system" (MNS) in macaque monkeys may provide a basis from which to explain some of the behavioral dysfunctions seen in individuals with autism spectrum disorders (ASD).We studied seven right-handed high-functioning male autistic and eight normal subjects (TD group) using functional magnetic resonance imaging during observation and execution of hand movements compared to a control condition (rest). The between group comparison of the contrast [observation versus rest] provided evidence of a bilateral greater activation of inferior frontal gyrus during observation of human motion than during rest for the ASD group than for the TD group. This hyperactivation of the pars opercularis (belonging to the MNS) during observation of human motion in autistic subjects provides strong support for the hypothesis of atypical activity of the MNS that may be at the core of the social deficits in autism. Copyright 2010 Elsevier B.V. All rights reserved.

  3. Activation of sea urchin sperm motility is accompanied by an increase in the creatine kinase exchange flux

    NARCIS (Netherlands)

    Dorsten, van F.A.; Wyss, M.; Wallimann, T.; Nicolaij, K.

    1997-01-01

    The kinetics of the creatine kinase (CK) reaction were studied in suspensions of quiescent and active, intact sea-urchin spermatozoa in artificial seawater, using 31P-NMR magnetization transfer. In inactive sperm, no CK-mediated exchange flux was detected, whereas in activated motile sperm, the

  4. Invasion from a cell aggregate—the roles of active cell motion and mechanical equilibrium

    International Nuclear Information System (INIS)

    Szabó, A; Varga, K; Czirók, A; Garay, T; Hegedűs, B

    2012-01-01

    Cell invasion from an aggregate into a surrounding extracellular matrix (ECM) is an important process during development disease, e.g., vascular network assembly or tumor progression. To describe the behavior emerging from autonomous cell motility, cell–cell adhesion and contact guidance by ECM filaments, we propose a suitably modified cellular Potts model. We consider an active cell motility process in which internal polarity is governed by a positive feedback from cell displacements, a mechanism that can result in highly persistent motion when constrained by an oriented ECM structure. The model allows us to explore the interplay between haptotaxis, matrix degradation and active cell movement. We show that for certain conditions the cells are able to both invade the ECM and follow the ECM tracks. Furthermore, we argue that enforcing mechanical equilibrium within a bulk cell mass is of key importance in multicellular simulations

  5. QUANTIFYING THE TOPOLOGY AND EVOLUTION OF A MAGNETIC FLUX ROPE ASSOCIATED WITH MULTI-FLARE ACTIVITIES

    International Nuclear Information System (INIS)

    Yang, Kai; Guo, Yang; Ding, M. D.

    2016-01-01

    Magnetic flux ropes (MFRs) play an important role in solar activities. The quantitative assessment of the topology of an MFR and its evolution is crucial for a better understanding of the relationship between the MFR and associated activities. In this paper, we investigate the magnetic field of active region (AR) 12017 from 2014 March 28–29, during which time 12 flares were triggered by intermittent eruptions of a filament (either successful or confined). Using vector magnetic field data from the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory , we calculate the magnetic energy and helicity injection in the AR, and extrapolate the 3D magnetic field with a nonlinear force-free field model. From the extrapolations, we find an MFR that is cospatial with the filament. We further determine the configuration of this MFR from the closed quasi-separatrix layer (QSL) around it. Then, we calculate the twist number and the magnetic helicity for the field lines composing the MFR. The results show that the closed QSL structure surrounding the MFR becomes smaller as a consequence of flare occurrence. We also find that the flares in our sample are mainly triggered by kink instability. Moreover, the twist number varies more sensitively than other parameters with the occurrence of flares.

  6. Quantifying the Topology and Evolution of a Magnetic Flux Rope Associated with Multi-flare Activities

    Science.gov (United States)

    Yang, Kai; Guo, Yang; Ding, M. D.

    2016-06-01

    Magnetic flux ropes (MFRs) play an important role in solar activities. The quantitative assessment of the topology of an MFR and its evolution is crucial for a better understanding of the relationship between the MFR and associated activities. In this paper, we investigate the magnetic field of active region (AR) 12017 from 2014 March 28-29, during which time 12 flares were triggered by intermittent eruptions of a filament (either successful or confined). Using vector magnetic field data from the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory, we calculate the magnetic energy and helicity injection in the AR, and extrapolate the 3D magnetic field with a nonlinear force-free field model. From the extrapolations, we find an MFR that is cospatial with the filament. We further determine the configuration of this MFR from the closed quasi-separatrix layer (QSL) around it. Then, we calculate the twist number and the magnetic helicity for the field lines composing the MFR. The results show that the closed QSL structure surrounding the MFR becomes smaller as a consequence of flare occurrence. We also find that the flares in our sample are mainly triggered by kink instability. Moreover, the twist number varies more sensitively than other parameters with the occurrence of flares.

  7. QUANTIFYING THE TOPOLOGY AND EVOLUTION OF A MAGNETIC FLUX ROPE ASSOCIATED WITH MULTI-FLARE ACTIVITIES

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Kai; Guo, Yang; Ding, M. D., E-mail: dmd@nju.edu.cn [School of Astronomy and Space Science, Nanjing University, Nanjing 210023 (China)

    2016-06-20

    Magnetic flux ropes (MFRs) play an important role in solar activities. The quantitative assessment of the topology of an MFR and its evolution is crucial for a better understanding of the relationship between the MFR and associated activities. In this paper, we investigate the magnetic field of active region (AR) 12017 from 2014 March 28–29, during which time 12 flares were triggered by intermittent eruptions of a filament (either successful or confined). Using vector magnetic field data from the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory , we calculate the magnetic energy and helicity injection in the AR, and extrapolate the 3D magnetic field with a nonlinear force-free field model. From the extrapolations, we find an MFR that is cospatial with the filament. We further determine the configuration of this MFR from the closed quasi-separatrix layer (QSL) around it. Then, we calculate the twist number and the magnetic helicity for the field lines composing the MFR. The results show that the closed QSL structure surrounding the MFR becomes smaller as a consequence of flare occurrence. We also find that the flares in our sample are mainly triggered by kink instability. Moreover, the twist number varies more sensitively than other parameters with the occurrence of flares.

  8. Scientific feedback from high heat flux actively cooled PFCs development, realization and first results in Tore Supra

    International Nuclear Information System (INIS)

    Grosman, A.; Bayetti, P.; Brosset, C.; Bucalossi, J.; Cordier, J.J.; Durocher, A.; Escourbiac, F.; Ghendrih, Ph.; Guilhem, D.; Gunn, J.; Loarer, T.; Lipa, M.; Mitteau, R.; Pegourie, B.; Reichle, R.; Schlosser, J.; Tsitrone, E.; Vallet, J.C.

    2004-01-01

    The implementation of actively cooled high heat flux plasma facing components (PFCs) are one of the major ingredients required for operating the Tore Supra tokamak with very long pulses. A pioneering activity has been developed in this field from the very beginning of the device operation that is today culminating with the routine operation of an actively cooled toroidal pumped limiter (TPL) capable to sustain up to 10 MW.m -2 of nominal convected heat flux. A technical feedback is given from the whole development up to the industrialization and focuses on a number of critical issues, such as bonding technology analysis, manufacture processes, repair processes, destructive and non destructive testing. The actual experience in Tore Supra allows to address the question of D retention on carbon walls. Redeposition on surfaces without plasma flux is suspected to cause the final 'burial' of about the injected gas during long discharges. (authors)

  9. Scientific feedback from high heat flux actively cooled PFCs development, realization and first results in Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Grosman, A.; Bayetti, P.; Brosset, C.; Bucalossi, J.; Cordier, J.J.; Durocher, A.; Escourbiac, F.; Ghendrih, Ph.; Guilhem, D.; Gunn, J.; Loarer, T.; Lipa, M.; Mitteau, R.; Pegourie, B.; Reichle, R.; Schlosser, J.; Tsitrone, E.; Vallet, J.C

    2004-07-01

    The implementation of actively cooled high heat flux plasma facing components (PFCs) are one of the major ingredients required for operating the Tore Supra tokamak with very long pulses. A pioneering activity has been developed in this field from the very beginning of the device operation that is today culminating with the routine operation of an actively cooled toroidal pumped limiter (TPL) capable to sustain up to 10 MW.m{sup -2} of nominal convected heat flux. A technical feedback is given from the whole development up to the industrialization and focuses on a number of critical issues, such as bonding technology analysis, manufacture processes, repair processes, destructive and non destructive testing. The actual experience in Tore Supra allows to address the question of D retention on carbon walls. Redeposition on surfaces without plasma flux is suspected to cause the final 'burial' of about the injected gas during long discharges. (authors)

  10. Effects of temperature and UVR on organic matter fluxes and the metabolic activity of Acropora muricata

    Directory of Open Access Journals (Sweden)

    Lucile Courtial

    2017-08-01

    Full Text Available Coral bleaching events are predicted to occur more frequently in the coming decades with global warming. The susceptibility of corals to bleaching during thermal stress episodes depends on many factors, including the magnitude of thermal stress and irradiance. The interactions among these two factors, and in particular with ultra-violet radiation (UVR, the most harmful component of light, are more complex than assumed, and are not yet well understood. This paper explores the individual and combined effects of temperature and UVR on the metabolism of Acropora muricata, one of the most abundant coral species worldwide. Particulate and dissolved organic matter (POM/DOM fluxes and organic matter (OM degradation by the mucus-associated bacteria were also monitored in all conditions. The results show that UVR exposure exacerbated the temperature-induced bleaching, but did not affect OM fluxes, which were only altered by seawater warming. Temperature increase induced a shift from POM release and DOM uptake in healthy corals to POM uptake and DOM release in stressed ones. POM uptake was linked to a significant grazing of pico- and nanoplankton particles during the incubation, to fulfil the energetic requirements of A. muricata in the absence of autotrophy. Finally, OM degradation by mucus-associated bacterial activity was unaffected by UVR exposure, but significantly increased under high temperature. Altogether, our results demonstrate that seawater warming and UVR not only affect coral physiology, but also the way corals interact with the surrounding seawater, with potential consequences for coral reef biogeochemical cycles and food webs.

  11. Spatial distribution of the neutron flux in the IEA-R1 reactor core obtained by means of foil activation

    International Nuclear Information System (INIS)

    Mestnik Filho, J.

    1979-01-01

    A three-dimensional distribution of the neutron flux in IEA-R1 reactor, obtained by activating gold foils, is presented. The foils of diameter 8mm and thickness 0,013mm were mounted on lucite plates and located between the fuel element plates. Foil activities were measured using a 3x3 inches Nal(Tl) scintilation detector calibrated against a 4πβγ coincidence detector. Foil positions were chosen to minimize the errors of measurement; the overall estimated error on the measured flux is 5%. (Author) [pt

  12. Initial experience with active breathing control of liver motion during ventilation

    International Nuclear Information System (INIS)

    Robertson, John M.; Sharpe, Michael B.; Jaffray, David A.; Wong, John W.

    1997-01-01

    Purpose: Recent evidence has shown that some patients with hepatic tumors can be safely irradiated to a dose well over twice the whole liver tolerance dose if portions of normal liver are spared. Correction during treatment planning for the ventilatory motion of the liver can add a large volume of normal liver to the planning target volume. Any reduction in ventilatory motion has the potential to allow a higher dose of radiation to be given safely. Active Breathing Control (ABC) can be used to temporarily stop the airflow to a patient, thus immobilizing the liver, at any part of a patient's ventilatory cycle. ABC during helical CT scanning can be used to study the full three dimensional motion of the liver and other abdominal organs during ventilation. Ultimately, if the use of ABC is found to be clinically feasible, tolerable for patients, and, most importantly, reproducible over time, then ABC may be used during radiation treatment. Materials and Methods: An ABC apparatus was constructed using a flow monitor and scissor valves on both the inhalation and exhalation paths to the patient. The patient breathed through either a mouthpiece or facemask during the procedure. The ventilatory cycle was displayed in real time. When a stable breathing pattern was observed, the ABC was activated at a specific lung volume, closing both scissors valves, and preventing ventilation. The length of time for comfortable activation of the ABC machine for the individual patient was determined during a teaching and practice period prior to CT scanning. Helical CT scans (slice thickness 0.5 cm) to assess the potential benefit of immobilizing breathing were obtained for normal breathing, end-inspiration and end-expiration. The reproducibility of ABC over time was assessed by repeating the end-inspiration scan both immediately and one week later. The contours of the liver and kidneys were entered for each study. Results: Five patients have undergone ABC study of the abdomen. End

  13. Envelope statistics of self-motion signals experienced by human subjects during everyday activities: Implications for vestibular processing.

    Science.gov (United States)

    Carriot, Jérome; Jamali, Mohsen; Cullen, Kathleen E; Chacron, Maurice J

    2017-01-01

    There is accumulating evidence that the brain's neural coding strategies are constrained by natural stimulus statistics. Here we investigated the statistics of the time varying envelope (i.e. a second-order stimulus attribute that is related to variance) of rotational and translational self-motion signals experienced by human subjects during everyday activities. We found that envelopes can reach large values across all six motion dimensions (~450 deg/s for rotations and ~4 G for translations). Unlike results obtained in other sensory modalities, the spectral power of envelope signals decreased slowly for low (2 Hz) temporal frequencies and thus was not well-fit by a power law. We next compared the spectral properties of envelope signals resulting from active and passive self-motion, as well as those resulting from signals obtained when the subject is absent (i.e. external stimuli). Our data suggest that different mechanisms underlie deviation from scale invariance in rotational and translational self-motion envelopes. Specifically, active self-motion and filtering by the human body cause deviation from scale invariance primarily for translational and rotational envelope signals, respectively. Finally, we used well-established models in order to predict the responses of peripheral vestibular afferents to natural envelope stimuli. We found that irregular afferents responded more strongly to envelopes than their regular counterparts. Our findings have important consequences for understanding the coding strategies used by the vestibular system to process natural second-order self-motion signals.

  14. High-resolution digital movies of emerging flux and horizontal flows in active regions on the sun

    Science.gov (United States)

    Topka, K.; Ferguson, S.; Frank, Z.; Tarbell, T.; Title, A.

    1988-01-01

    High-resolution observations of active regions in many wavelength bands obtained at the Vacuum Tower Telescope of NSO/Sunspot (Sacramento Peak) are presented. The SOUP tunable filter, HRSO 1024 x 1024 CCD camera, and a sunspot tracker for image stabilization were used. Subarrays of 512 x 512 pixels were processed digitally and recorded on videodisk in movie format. The movies with 0.5 to 1 arcsecond resolution of the following simultaneous observations were shown: green continuum, longitudinal magnetogram, Doppler velocity, Fe I 5576 A line center, H alpha wings, and H alpha line center. The best set of movies show a 90 x 90 arcsecond field-of-view of an active region at S29, W11. When viewed at speeds of a few thousand times real-time, the photospheric movies clearly show the active region fields being distorted by a remarkable combination of systematic flows and small eruptions of new flux. Flux emergence is most easily discovered in line center movies: an elongated dark feature appears first, followed soon after by bright points at one or both ends. A brief, strong upflow is seen when the dark feature first appears; downflow in the bright points persists much longer. The magnetic flux appears to increase gradually over this extended period. Some of the flux emergence events were studied in detail, with measurements of horizontal and vertical velocities and magnetic flux versus time within one footpoint of the loop.

  15. High-resolution digital movies of emerging flux and horizontal flows in active regions on the sun

    International Nuclear Information System (INIS)

    Topka, K.; Ferguson, S.; Frank, Z.; Tarbell, T.; Title, A.

    1988-01-01

    High-resolution observations of active regions in many wavelength bands obtained at the Vacuum Tower Telescope of NSO/Sunspot (Sacramento Peak) are presented. The SOUP tunable filter, HRSO 1024 x 1024 CCD camera, and a sunspot tracker for image stabilization were used. Subarrays of 512 x 512 pixels were processed digitally and recorded on videodisk in movie format. The movies with 0.5 to 1 arcsecond resolution of the following simultaneous observations were shown: green continuum, longitudinal magnetogram, Doppler velocity, Fe I 5576 A line center, H alpha wings, and H alpha line center. The best set of movies show a 90 x 90 arcsecond field-of-view of an active region at S29, W11. When viewed at speeds of a few thousand times real-time, the photospheric movies clearly show the active region fields being distorted by a remarkable combination of systematic flows and small eruptions of new flux. Flux emergence is most easily discovered in line center movies: an elongated dark feature appears first, followed soon after by bright points at one or both ends. A brief, strong upflow is seen when the dark feature first appears; downflow in the bright points persists much longer. The magnetic flux appears to increase gradually over this extended period. Some of the flux emergence events were studied in detail, with measurements of horizontal and vertical velocities and magnetic flux versus time within one footpoint of the loop

  16. High-resolution digital movies of emerging flux and horizontal flows in active regions on the sun

    Science.gov (United States)

    Topka, K.; Ferguson, S.; Frank, Z.; Tarbell, T.; Title, A.

    1988-11-01

    High-resolution observations of active regions in many wavelength bands obtained at the Vacuum Tower Telescope of NSO/Sunspot (Sacramento Peak) are presented. The SOUP tunable filter, HRSO 1024 x 1024 CCD camera, and a sunspot tracker for image stabilization were used. Subarrays of 512 x 512 pixels were processed digitally and recorded on videodisk in movie format. The movies with 0.5 to 1 arcsecond resolution of the following simultaneous observations were shown: green continuum, longitudinal magnetogram, Doppler velocity, Fe I 5576 A line center, H alpha wings, and H alpha line center. The best set of movies show a 90 x 90 arcsecond field-of-view of an active region at S29, W11. When viewed at speeds of a few thousand times real-time, the photospheric movies clearly show the active region fields being distorted by a remarkable combination of systematic flows and small eruptions of new flux. Flux emergence is most easily discovered in line center movies: an elongated dark feature appears first, followed soon after by bright points at one or both ends. A brief, strong upflow is seen when the dark feature first appears; downflow in the bright points persists much longer. The magnetic flux appears to increase gradually over this extended period. Some of the flux emergence events were studied in detail, with measurements of horizontal and vertical velocities and magnetic flux versus time within one footpoint of the loop.

  17. Understanding and Visualizing Multitasking and Task Switching Activities: A Time Motion Study to Capture Nursing Workflow.

    Science.gov (United States)

    Yen, Po-Yin; Kelley, Marjorie; Lopetegui, Marcelo; Rosado, Amber L; Migliore, Elaina M; Chipps, Esther M; Buck, Jacalyn

    2016-01-01

    A fundamental understanding of multitasking within nursing workflow is important in today's dynamic and complex healthcare environment. We conducted a time motion study to understand nursing workflow, specifically multitasking and task switching activities. We used TimeCaT, a comprehensive electronic time capture tool, to capture observational data. We established inter-observer reliability prior to data collection. We completed 56 hours of observation of 10 registered nurses. We found, on average, nurses had 124 communications and 208 hands-on tasks per 4-hour block of time. They multitasked (having communication and hands-on tasks simultaneously) 131 times, representing 39.48% of all times; the total multitasking duration ranges from 14.6 minutes to 109 minutes, 44.98 minutes (18.63%) on average. We also reviewed workflow visualization to uncover the multitasking events. Our study design and methods provide a practical and reliable approach to conducting and analyzing time motion studies from both quantitative and qualitative perspectives.

  18. Control of a Virtual Vehicle Influences Postural Activity and Motion Sickness

    Science.gov (United States)

    Dong, Xiao; Yoshida, Ken; Stoffregen, Thomas A.

    2011-01-01

    Everyday experience suggests that drivers are less susceptible to motion sickness than passengers. In the context of inertial motion (i.e., physical displacement), this effect has been confirmed in laboratory research using whole body motion devices. We asked whether a similar effect would occur in the context of simulated vehicles in a visual…

  19. Ambulatory activity monitoring: Progress in measurement of activity, posture, and specific motion patterns in daily life

    NARCIS (Netherlands)

    J.B.J. Bussmann (Hans); U.W. Ebner-Priemer (Ulrich); J. Fahrenberg (Jochen)

    2009-01-01

    textabstractBehavior is central to psychology in almost any definition. Although observable activity is a core aspect of behavior, assessment strategies have tended to focus on emotional, cognitive, or physiological responses. When physical activity is assessed, it is done so mostly with

  20. Photoneutron Flux Measurement via Neutron Activation Analysis in a Radiotherapy Bunker with an 18 MV Linear Accelerator

    Science.gov (United States)

    Çeçen, Yiğit; Gülümser, Tuğçe; Yazgan, Çağrı; Dapo, Haris; Üstün, Mahmut; Boztosun, Ismail

    2017-09-01

    In cancer treatment, high energy X-rays are used which are produced by linear accelerators (LINACs). If the energy of these beams is over 8 MeV, photonuclear reactions occur between the bremsstrahlung photons and the metallic parts of the LINAC. As a result of these interactions, neutrons are also produced as secondary radiation products (γ,n) which are called photoneutrons. The study aims to map the photoneutron flux distribution within the LINAC bunker via neutron activation analysis (NAA) using indium-cadmium foils. Irradiations made at different gantry angles (0°, 90°, 180° and 270°) with a total of 91 positions in the Philips SLI-25 linear accelerator treatment room and location-based distribution of thermal neutron flux was obtained. Gamma spectrum analysis was carried out with high purity germanium (HPGe) detector. Results of the analysis showed that the maximum neutron flux in the room occurred at just above of the LINAC head (1.2x105 neutrons/cm2.s) which is compatible with an americium-beryllium (Am-Be) neutron source. There was a 90% decrease of flux at the walls and at the start of the maze with respect to the maximum neutron flux. And, just in front of the LINAC door, inside the room, neutron flux was measured less than 1% of the maximum.

  1. Photoneutron Flux Measurement via Neutron Activation Analysis in a Radiotherapy Bunker with an 18 MV Linear Accelerator

    Directory of Open Access Journals (Sweden)

    Çeçen Yiğit

    2017-01-01

    Full Text Available In cancer treatment, high energy X-rays are used which are produced by linear accelerators (LINACs. If the energy of these beams is over 8 MeV, photonuclear reactions occur between the bremsstrahlung photons and the metallic parts of the LINAC. As a result of these interactions, neutrons are also produced as secondary radiation products (γ,n which are called photoneutrons. The study aims to map the photoneutron flux distribution within the LINAC bunker via neutron activation analysis (NAA using indium-cadmium foils. Irradiations made at different gantry angles (0°, 90°, 180° and 270° with a total of 91 positions in the Philips SLI-25 linear accelerator treatment room and location-based distribution of thermal neutron flux was obtained. Gamma spectrum analysis was carried out with high purity germanium (HPGe detector. Results of the analysis showed that the maximum neutron flux in the room occurred at just above of the LINAC head (1.2x105 neutrons/cm2.s which is compatible with an americium-beryllium (Am-Be neutron source. There was a 90% decrease of flux at the walls and at the start of the maze with respect to the maximum neutron flux. And, just in front of the LINAC door, inside the room, neutron flux was measured less than 1% of the maximum.

  2. Neutron activation analysis: Modelling studies to improve the neutron flux of Americium–Beryllium source

    Directory of Open Access Journals (Sweden)

    Abdessamad Didi

    2017-06-01

    Full Text Available Americium–beryllium (Am-Be; n, γ is a neutron emitting source used in various research fields such as chemistry, physics, geology, archaeology, medicine, and environmental monitoring, as well as in the forensic sciences. It is a mobile source of neutron activity (20 Ci, yielding a small thermal neutron flux that is water moderated. The aim of this study is to develop a model to increase the neutron thermal flux of a source such as Am-Be. This study achieved multiple advantageous results: primarily, it will help us perform neutron activation analysis. Next, it will give us the opportunity to produce radio-elements with short half-lives. Am-Be single and multisource (5 sources experiments were performed within an irradiation facility with a paraffin moderator. The resulting models mainly increase the thermal neutron flux compared to the traditional method with water moderator.

  3. A Long Decay of X-Ray Flux and Spectral Evolution in the Supersoft Active Galactic Nucleus GSN 069

    Science.gov (United States)

    Shu, X. W.; Wang, S. S.; Dou, L. M.; Jiang, N.; Wang, J. X.; Wang, T. G.

    2018-04-01

    GSN 069 is an optically identified very low-mass active galactic nuclei (AGN) that shows supersoft X-ray emission. The source is known to exhibit a huge X-ray outburst, with flux increased by more than a factor of ∼240 compared to the quiescence state. We report its long-term evolution in the X-ray flux and spectral variations over a timescale of ∼decade, using both new and archival X-ray observations from the XMM-Newton and Swift. The new Swift observations detected the source in its lowest level of X-ray activity since the outburst, a factor of ∼4 lower in the 0.2–2 keV flux than that obtained with the XMM-Newton observations nearly eight years ago. Combining with the historical X-ray measurements, we find that the X-ray flux is decreasing slowly. There seemed to be spectral softening associated with the drop of X-ray flux. In addition, we find evidence for the presence of a weak, variable, hard X-ray component, in addition to the dominant thermal blackbody emission reported before. The long decay of X-ray flux and spectral evolution, as well as the supersoft X-ray spectra, suggest that the source could be a tidal disruption event (TDE), though a highly variable AGN cannot be fully ruled out. Further continued X-ray monitoring would be required to test the TDE interpretation, by better determining the flux evolution in the decay phase.

  4. Inferring 222Rn soil fluxes from ambient 222Rn activity and eddy covariance measurements of CO2

    Directory of Open Access Journals (Sweden)

    S. van der Laan

    2016-11-01

    Full Text Available We present a new methodology, which we call Single Pair of Observations Technique with Eddy Covariance (SPOT-EC, to estimate regional-scale surface fluxes of 222Rn from tower-based observations of 222Rn activity concentration, CO2 mole fractions and direct CO2 flux measurements from eddy covariance. For specific events, the regional (222Rn surface flux is calculated from short-term changes in ambient (222Rn activity concentration scaled by the ratio of the mean CO2 surface flux for the specific event to the change in its observed mole fraction. The resulting 222Rn surface emissions are integrated in time (between the moment of observation and the last prior background levels and space (i.e. over the footprint of the observations. The measurement uncertainty obtained is about ±15 % for diurnal events and about ±10 % for longer-term (e.g. seasonal or annual means. The method does not provide continuous observations, but reliable daily averages can be obtained. We applied our method to in situ observations from two sites in the Netherlands: Cabauw station (CBW and Lutjewad station (LUT. For LUT, which is an intensive agricultural site, we estimated a mean 222Rn surface flux of (0.29 ± 0.02 atoms cm−2 s−1 with values  > 0.5 atoms cm−2 s−1 to the south and south-east. For CBW we estimated a mean 222Rn surface flux of (0.63 ± 0.04 atoms cm−2 s−1. The highest values were observed to the south-west, where the soil type is mainly river clay. For both stations good agreement was found between our results and those from measurements with soil chambers and two recently published 222Rn soil flux maps for Europe. At both sites, large spatial and temporal variability of 222Rn surface fluxes were observed which would be impractical to measure with a soil chamber. SPOT-EC, therefore, offers an important new tool for estimating regional-scale 222Rn surface fluxes. Practical applications furthermore include

  5. Recommended survey designs for occupancy modelling using motion-activated cameras: insights from empirical wildlife data

    Directory of Open Access Journals (Sweden)

    Graeme Shannon

    2014-08-01

    Full Text Available Motion-activated cameras are a versatile tool that wildlife biologists can use for sampling wild animal populations to estimate species occurrence. Occupancy modelling provides a flexible framework for the analysis of these data; explicitly recognizing that given a species occupies an area the probability of detecting it is often less than one. Despite the number of studies using camera data in an occupancy framework, there is only limited guidance from the scientific literature about survey design trade-offs when using motion-activated cameras. A fuller understanding of these trade-offs will allow researchers to maximise available resources and determine whether the objectives of a monitoring program or research study are achievable. We use an empirical dataset collected from 40 cameras deployed across 160 km2 of the Western Slope of Colorado, USA to explore how survey effort (number of cameras deployed and the length of sampling period affects the accuracy and precision (i.e., error of the occupancy estimate for ten mammal and three virtual species. We do this using a simulation approach where species occupancy and detection parameters were informed by empirical data from motion-activated cameras. A total of 54 survey designs were considered by varying combinations of sites (10–120 cameras and occasions (20–120 survey days. Our findings demonstrate that increasing total sampling effort generally decreases error associated with the occupancy estimate, but changing the number of sites or sampling duration can have very different results, depending on whether a species is spatially common or rare (occupancy = ψ and easy or hard to detect when available (detection probability = p. For rare species with a low probability of detection (i.e., raccoon and spotted skunk the required survey effort includes maximizing the number of sites and the number of survey days, often to a level that may be logistically unrealistic for many studies. For common

  6. Active Head Motion Compensation of TMS Robotic System Using Neuro-Fuzzy Estimation

    Directory of Open Access Journals (Sweden)

    Wan Zakaria W.N.

    2016-01-01

    Full Text Available Transcranial Magnetic Stimulation (TMS allows neuroscientist to study human brain behaviour and also become an important technique for changing the activity of brain neurons and the functions they sub serve. However, conventional manual procedure and robotized TMS are currently unable to precisely position the TMS coil because of unconstrained subject’s head movement and excessive contact force between the coil and subject’s head. This paper addressed this challenge by proposing an adaptive neuro-fuzzy force control to enable low contact force with a moving target surface. A learning and adaption mechanism is included in the control scheme to improve position disturbance estimation. The results show the ability of the proposed force control scheme to compensate subject’s head motions while maintaining desired contact force, thus allowing for more accurate and repeatable TMS procedures.

  7. The calcium feedback loop and T cell activation: how cytoskeleton networks control intracellular calcium flux.

    Science.gov (United States)

    Joseph, Noah; Reicher, Barak; Barda-Saad, Mira

    2014-02-01

    During T cell activation, the engagement of a T cell with an antigen-presenting cell (APC) results in rapid cytoskeletal rearrangements and a dramatic increase of intracellular calcium (Ca(2+)) concentration, downstream to T cell antigen receptor (TCR) ligation. These events facilitate the organization of an immunological synapse (IS), which supports the redistribution of receptors, signaling molecules and organelles towards the T cell-APC interface to induce downstream signaling events, ultimately supporting T cell effector functions. Thus, Ca(2+) signaling and cytoskeleton rearrangements are essential for T cell activation and T cell-dependent immune response. Rapid release of Ca(2+) from intracellular stores, e.g. the endoplasmic reticulum (ER), triggers the opening of Ca(2+) release-activated Ca(2+) (CRAC) channels, residing in the plasma membrane. These channels facilitate a sustained influx of extracellular Ca(2+) across the plasma membrane in a process termed store-operated Ca(2+) entry (SOCE). Because CRAC channels are themselves inhibited by Ca(2+) ions, additional factors are suggested to enable the sustained Ca(2+) influx required for T cell function. Among these factors, we focus here on the contribution of the actin and microtubule cytoskeleton. The TCR-mediated increase in intracellular Ca(2+) evokes a rapid cytoskeleton-dependent polarization, which involves actin cytoskeleton rearrangements and microtubule-organizing center (MTOC) reorientation. Here, we review the molecular mechanisms of Ca(2+) flux and cytoskeletal rearrangements, and further describe the way by which the cytoskeletal networks feedback to Ca(2+) signaling by controlling the spatial and temporal distribution of Ca(2+) sources and sinks, modulating TCR-dependent Ca(2+) signals, which are required for an appropriate T cell response. This article is part of a Special Issue entitled: Reciprocal influences between cell cytoskeleton and membrane channels, receptors and transporters

  8. Practical Wide-speed-range Sensorless Control System for Permanent Magnet Reluctance Synchronous Motor Drives via Active Flux Model

    DEFF Research Database (Denmark)

    Ancuti, Mihaela Codruta; Tutelea, Lucian; Andreescu, Gheorghe-Daniel

    2014-01-01

    This article introduces a control strategy to obtain near-maximum available torque in a wide speed range with sensorless operation via the active flux concept for permanent magnet-reluctance synchronous motor drives. A new torque dq current reference calculator is proposed, with reference torque...

  9. Bioturbation and dissolved organic matter enhance contaminant fluxes from sediment treated with powdered and granular activated carbon

    NARCIS (Netherlands)

    Kupryianchyk, D.; Noori, A.; Rakowska, M.I.; Grotenhuis, J.T.C.; Koelmans, A.A.

    2013-01-01

    Sediment amendment with activated carbon (AC) is a promising technique for in situ sediment remediation. To date it is not clear whether this technique sufficiently reduces sediment-to-water fluxes of sediment-bound hydrophobic organic chemicals (HOCs) in the presence of bioturbators. Here, we

  10. Comparison of electromyographic activity and range of neck motion in violin students with and without neck pain during playing.

    Science.gov (United States)

    Park, Kyue-nam; Kwon, Oh-yun; Ha, Sung-min; Kim, Su-jung; Choi, Hyun-jung; Weon, Jong-hyuck

    2012-12-01

    Neck pain is common in violin students during a musical performance. The purpose of this study was to compare electromyographic (EMG) activity in superficial neck muscles with neck motion when playing the violin as well as neck range of motion (ROM) at rest, between violin students with and without neck pain. Nine violin students with neck pain and nine age- and gender-matched subjects without neck pain were recruited. Muscle activity of the bilateral upper trapezius, sternocleidomastoid, and superficial cervical extensor muscles was measured using surface EMG. Kinematic data on neck motion while playing and active neck ROM were also measured using a three-dimensional motion analysis system. Independent t-tests were used to compare EMG activity with kinematic data between groups. These analyses revealed that while playing, both the angle of left lateral bending and leftward rotation of the cervical spine were significantly greater in the neck pain group than among those without neck pain. Similarly, EMG activity of the left upper trapezius, both cervical extensors, and both sternocleidomastoid muscles were significantly greater in the neck pain group. The active ROM of left axial rotation was significantly lower in the neck pain group. These results suggest that an asymmetric playing posture and the associated increased muscle activity as well as decreased neck axial rotation may contribute to neck pain in violin students.

  11. Activation analysis of stainless steel flux monitors using 252Cf neutron sources

    International Nuclear Information System (INIS)

    Williams, J.G.; Newton, T.H. Jr.; Cogburn, C.O.

    1984-01-01

    Activation analysis was performed on stainless steel beads from a chain which is used in reactor pressure vessel surveillance experiments at the Arkansas Power and Light Company reactors. The beads allow monitoring of two fast and three thermal neutron induced reactions: 58 Ni(n,p) 58 Co, 54 Fe(n,p) 54 Mn, 58 Fe(n,γ) 59 Fe, 59 Co(n,γ) 60 Co and 50 Cr(n,γ) 51 Cr. The analysis was performed using 12 beads from various positions along 5 different batches of chain and standard materials in an H 2 O moderator tank using two intense californium sources which had a total neutron emission rate of 3.97 x 10 10 /s. Semiconductor gamma spectrometers were used to count the products of the above reactions in the specimens. The percentage by weight of the iron, chromium and cobalt in the beads were found to be 62.1%, 20.2% and 0.120%, respectively. The excellent uniformity found in the bead compositions demonstrates the reproducibility of the experimental techniques and enhances considerably the value of the beads as neutron flux montitors

  12. Wearable motion sensors to continuously measure real-world physical activities.

    Science.gov (United States)

    Dobkin, Bruce H

    2013-12-01

    Rehabilitation for sensorimotor impairments aims to improve daily activities, walking, exercise, and motor skills. Monitoring of practice and measuring outcomes, however, is usually restricted to laboratory-based procedures and self-reports. Mobile health devices may reverse these confounders of daily care and research trials. Wearable, wireless motion sensor data, analyzed by activity pattern-recognition algorithms, can describe the type, quantity, and quality of mobility-related activities in the community. Data transmission from the sensors to a cell phone and the Internet enable continuous monitoring. Remote access to laboratory quality data about walking speed, duration and distance, gait asymmetry and smoothness of movements, as well as cycling, exercise, and skills practice, opens new opportunities to engage patients in progressive, personalized therapies with feedback about the performance. Clinical trial designs will be able to include remote verification of the integrity of complex physical interventions and compliance with practice, as well as capture repeated, ecologically sound, ratio scale outcome measures. Given the progressively falling cost of miniaturized wearable gyroscopes, accelerometers, and other physiologic sensors, as well as inexpensive data transmission, sensing systems may become as ubiquitous as cell phones for healthcare. Neurorehabilitation can develop these mobile health platforms for daily care and clinical trials to improve exercise and fitness, skills learning, and physical functioning.

  13. Active Deformation in the Overriding Plate Associated with Temporal Changes of the Philippine Sea Plate Motion

    Science.gov (United States)

    Ishiyama, T.; Sato, H.; Van Horne, A.

    2015-12-01

    We present detailed geologic evidence linking changes over time in Philippine Sea plate (PHS) motion and intracontinental deformation in central and southwest (SW) Japan during the Pliocene and after. In the early Pliocene, subduction of the PHS plate under SW Japan restarted in a northerly direction after period of deceleration or cessation. Later, motion changed to a more westerly direction. Corresponding geological changes found in the overriding plate include unconformities in the forearc basins, changes in slip sense on faults, depocenter migration, re-organization of drainage systems and volcanism. Quaternary intraplate deformation is prominent north of the Median Tectonic Line (MTL) inactive segment, above a shallow flat slab. In contrast, less Quaternary tectonic activity is found north of the MTL active segment which lies over a steadily-slipping portion of the subducting slab that behaves as a less-deformed rigid block. Depocenters and active thrusting have migrated north/northwestward over the past 5 My above the shallow flat slab segment of the PHS. We reconstructed the Plio-Pleistocene migration history using Neogene stratigraphy and shallow seismic reflection profiles. We see shallow PHS slab contact with the lower continental crust in our deep seismic reflection profiles, which may explain its enhanced downward drag of the overriding plate and synchronous strong compression in the crust. We find evidence of more westerly PHS plate subduction since the middle Pleistocene in (1) unconformities in the Kumano forearc basin deposits in SW Japan, (2) drastic stream captures in Shikoku, and (3) concordant changes in fault slip sense from thrust to dextral slip along the MTL. Oblique subduction could have induced stronger horizontal stress in the overriding plate above the shallow flat slab which could account for the increasing geologic slip rate observed on active structures. During four repetitions of megathrust earthquake sequences since the 17th century

  14. Fault-tolerant feature-based estimation of space debris rotational motion during active removal missions

    Science.gov (United States)

    Biondi, Gabriele; Mauro, Stefano; Pastorelli, Stefano; Sorli, Massimo

    2018-05-01

    One of the key functionalities required by an Active Debris Removal mission is the assessment of the target kinematics and inertial properties. Passive sensors, such as stereo cameras, are often included in the onboard instrumentation of a chaser spacecraft for capturing sequential photographs and for tracking features of the target surface. A plenty of methods, based on Kalman filtering, are available for the estimation of the target's state from feature positions; however, to guarantee the filter convergence, they typically require continuity of measurements and the capability of tracking a fixed set of pre-defined features of the object. These requirements clash with the actual tracking conditions: failures in feature detection often occur and the assumption of having some a-priori knowledge about the shape of the target could be restrictive in certain cases. The aim of the presented work is to propose a fault-tolerant alternative method for estimating the angular velocity and the relative magnitudes of the principal moments of inertia of the target. Raw data regarding the positions of the tracked features are processed to evaluate corrupted values of a 3-dimentional parameter which entirely describes the finite screw motion of the debris and which primarily is invariant on the particular set of considered features of the object. Missing values of the parameter are completely restored exploiting the typical periodicity of the rotational motion of an uncontrolled satellite: compressed sensing techniques, typically adopted for recovering images or for prognostic applications, are herein used in a completely original fashion for retrieving a kinematic signal that appears sparse in the frequency domain. Due to its invariance about the features, no assumptions are needed about the target's shape and continuity of the tracking. The obtained signal is useful for the indirect evaluation of an attitude signal that feeds an unscented Kalman filter for the estimation of

  15. AMPK activation protects cells from oxidative stress-induced senescence via autophagic flux restoration and intracellular NAD(+) elevation.

    Science.gov (United States)

    Han, Xiaojuan; Tai, Haoran; Wang, Xiaobo; Wang, Zhe; Zhou, Jiao; Wei, Xiawei; Ding, Yi; Gong, Hui; Mo, Chunfen; Zhang, Jie; Qin, Jianqiong; Ma, Yuanji; Huang, Ning; Xiang, Rong; Xiao, Hengyi

    2016-06-01

    AMPK activation is beneficial for cellular homeostasis and senescence prevention. However, the molecular events involved in AMPK activation are not well defined. In this study, we addressed the mechanism underlying the protective effect of AMPK on oxidative stress-induced senescence. The results showed that AMPK was inactivated in senescent cells. However, pharmacological activation of AMPK by metformin and berberine significantly prevented the development of senescence and, accordingly, inhibition of AMPK by Compound C was accelerated. Importantly, AMPK activation prevented hydrogen peroxide-induced impairment of the autophagic flux in senescent cells, evidenced by the decreased p62 degradation, GFP-RFP-LC3 cancellation, and activity of lysosomal hydrolases. We also found that AMPK activation restored the NAD(+) levels in the senescent cells via a mechanism involving mostly the salvage pathway for NAD(+) synthesis. In addition, the mechanistic relationship of autophagic flux and NAD(+) synthesis and the involvement of mTOR and Sirt1 activities were assessed. In summary, our results suggest that AMPK prevents oxidative stress-induced senescence by improving autophagic flux and NAD(+) homeostasis. This study provides a new insight for exploring the mechanisms of aging, autophagy and NAD(+) homeostasis, and it is also valuable in the development of innovative strategies to combat aging. © 2016 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  16. Modulation of intracellular calcium waves and triggered activities by mitochondrial ca flux in mouse cardiomyocytes.

    Directory of Open Access Journals (Sweden)

    Zhenghang Zhao

    Full Text Available Recent studies have suggested that mitochondria may play important roles in the Ca(2+ homeostasis of cardiac myocytes. However, it is still unclear if mitochondrial Ca(2+ flux can regulate the generation of Ca(2+ waves (CaWs and triggered activities in cardiac myocytes. In the present study, intracellular/cytosolic Ca(2+ (Cai (2+ was imaged in Fluo-4-AM loaded mouse ventricular myocytes. Spontaneous sarcoplasmic reticulum (SR Ca(2+ release and CaWs were induced in the presence of high (4 mM external Ca(2+ (Cao (2+. The protonophore carbonyl cyanide p-(trifluoromethoxyphenylhydrazone (FCCP reversibly raised basal Cai (2+ levels even after depletion of SR Ca(2+ in the absence of Cao (2+ , suggesting Ca(2+ release from mitochondria. FCCP at 0.01 - 0.1 µM partially depolarized the mitochondrial membrane potential (Δψ m and increased the frequency and amplitude of CaWs in a dose-dependent manner. Simultaneous recording of cell membrane potentials showed the augmentation of delayed afterdepolarization amplitudes and frequencies, and induction of triggered action potentials. The effect of FCCP on CaWs was mimicked by antimycin A (an electron transport chain inhibitor disrupting Δψ m or Ru360 (a mitochondrial Ca(2+ uniporter inhibitor, but not by oligomycin (an ATP synthase inhibitor or iodoacetic acid (a glycolytic inhibitor, excluding the contribution of intracellular ATP levels. The effects of FCCP on CaWs were counteracted by the mitochondrial permeability transition pore blocker cyclosporine A, or the mitochondrial Ca(2+ uniporter activator kaempferol. Our results suggest that mitochondrial Ca(2+ release and uptake exquisitely control the local Ca(2+ level in the micro-domain near SR ryanodine receptors and play an important role in regulation of intracellular CaWs and arrhythmogenesis.

  17. Decreased cortical activation in response to a motion stimulus in anisometropic amblyopic eyes using functional magnetic resonance imaging.

    Science.gov (United States)

    Bonhomme, Gabrielle R; Liu, Grant T; Miki, Atsushi; Francis, Ellie; Dobre, M-C; Modestino, Edward J; Aleman, David O; Haselgrove, John C

    2006-12-01

    Motion perception abnormalities and extrastriate abnormalities have been suggested in amblyopia. Functional MRI (fMRI) and motion stimuli were used to study whether interocular differences in activation are detectable in motion-sensitive cortical areas in patients with anisometropic amblyopia. We performed fMRI at 1.5 T 4 control subjects (20/20 OU), 1 with monocular suppression (20/25), and 2 with anisometropic amblyopia (20/60, 20/800). Monocular suppression was thought to be form fruste of amblyopia. The experimental stimulus consisted of expanding and contracting concentric rings, whereas the control condition consisted of stationary concentric rings. Activation was determined by contrasting the 2 conditions for each eye. Significant fMRI activation and comparable right and left eye activation was found in V3a and V5 in all control subjects (Average z-values in L vs R contrast 0.42, 0.43) and in the subject with monocular suppression (z = 0.19). The anisometropes exhibited decreased extrastriate activation in their amblyopic eyes compared with the fellow eyes (zs = 2.12, 2.76). Our data suggest motion-sensitive cortical structures may be less active when anisometropic amblyopic eyes are stimulated with moving rings. These results support the hypothesis that extrastriate cortex is affected in anisometropic amblyopia. Although suggestive of a magnocellular defect, the exact mechanism is unclear.

  18. Slow motion in films and video clips: Music influences perceived duration and emotion, autonomic physiological activation and pupillary responses.

    Science.gov (United States)

    Wöllner, Clemens; Hammerschmidt, David; Albrecht, Henning

    2018-01-01

    Slow motion scenes are ubiquitous in screen-based audiovisual media and are typically accompanied by emotional music. The strong effects of slow motion on observers are hypothetically related to heightened emotional states in which time seems to pass more slowly. These states are simulated in films and video clips, and seem to resemble such experiences in daily life. The current study investigated time perception and emotional response to media clips containing decelerated human motion, with or without music using psychometric and psychophysiological testing methods. Participants were presented with slow-motion scenes taken from commercial films, ballet and sports footage, as well as the same scenes converted to real-time. Results reveal that slow-motion scenes, compared to adapted real-time scenes, led to systematic underestimations of duration, lower perceived arousal but higher valence, lower respiration rates and smaller pupillary diameters. The presence of music compared to visual-only presentations strongly affected results in terms of higher accuracy in duration estimates, higher perceived arousal and valence, higher physiological activation and larger pupillary diameters, indicating higher arousal. Video genre affected responses in addition. These findings suggest that perceiving slow motion is not related to states of high arousal, but rather affects cognitive dimensions of perceived time and valence. Music influences these experiences profoundly, thus strengthening the impact of stretched time in audiovisual media.

  19. A DOUBLE-RING ALGORITHM FOR MODELING SOLAR ACTIVE REGIONS: UNIFYING KINEMATIC DYNAMO MODELS AND SURFACE FLUX-TRANSPORT SIMULATIONS

    International Nuclear Information System (INIS)

    Munoz-Jaramillo, Andres; Martens, Petrus C. H.; Nandy, Dibyendu; Yeates, Anthony R.

    2010-01-01

    The emergence of tilted bipolar active regions (ARs) and the dispersal of their flux, mediated via processes such as diffusion, differential rotation, and meridional circulation, is believed to be responsible for the reversal of the Sun's polar field. This process (commonly known as the Babcock-Leighton mechanism) is usually modeled as a near-surface, spatially distributed α-effect in kinematic mean-field dynamo models. However, this formulation leads to a relationship between polar field strength and meridional flow speed which is opposite to that suggested by physical insight and predicted by surface flux-transport simulations. With this in mind, we present an improved double-ring algorithm for modeling the Babcock-Leighton mechanism based on AR eruption, within the framework of an axisymmetric dynamo model. Using surface flux-transport simulations, we first show that an axisymmetric formulation-which is usually invoked in kinematic dynamo models-can reasonably approximate the surface flux dynamics. Finally, we demonstrate that our treatment of the Babcock-Leighton mechanism through double-ring eruption leads to an inverse relationship between polar field strength and meridional flow speed as expected, reconciling the discrepancy between surface flux-transport simulations and kinematic dynamo models.

  20. Overview of results of the first phase of validation activities for the IFMIF High Flux Test Module

    Energy Technology Data Exchange (ETDEWEB)

    Arbeiter, Frederik, E-mail: frederik.arbeiter@kit.edu [Karlsruhe Institute of Technology, Karlsruhe (Germany); Chen Yuming; Dolensky, Bernhard; Freund, Jana; Heupel, Tobias; Klein, Christine; Scheel, Nicola; Schlindwein, Georg [Karlsruhe Institute of Technology, Karlsruhe (Germany)

    2012-08-15

    Highlights: Black-Right-Pointing-Pointer Validation of computational fluid dynamics (CFD) modeling approach for application in the IFMIF High Flux Test Module. Black-Right-Pointing-Pointer Fabrication of prototypes of the irradiation capsules of the IFMIF High Flux Test Module. - Abstract: The international fusion materials irradiation facility (IFMIF) is projected to create an experimentally validated database of material properties relevant for fusion reactor designs. The IFMIF High Flux Test Module is the dedicated experiment to irradiate alloys in the temperature range 250-550 Degree-Sign C and up to 50 displacements per atom per irradiation cycle. The High Flux Test Module is developed to maximize the specimen payload in the restricted irradiation volume, and to minimize the temperature spread within each specimen bundle. Low pressure helium mini-channel cooling is used to offer a high integration density. Due to the demanding thermo-hydraulic and mechanical conditions, the engineering design process (involving numerical neutronic, thermo-hydraulic and mechanical analyses) is supported by extensive experimental validation activities. This paper reports on the prototype manufacturing, thermo-hydraulic modeling experiments and component tests, as well as on mechanical testing. For the testing of the 1:1 prototype of the High Flux Test Module, a dedicated test facility, the Helium Loop Karlsruhe-Low Pressure (HELOKA-LP) has been taken into service.

  1. Overview of results of the first phase of validation activities for the IFMIF High Flux Test Module

    International Nuclear Information System (INIS)

    Arbeiter, Frederik; Chen Yuming; Dolensky, Bernhard; Freund, Jana; Heupel, Tobias; Klein, Christine; Scheel, Nicola; Schlindwein, Georg

    2012-01-01

    Highlights: ► Validation of computational fluid dynamics (CFD) modeling approach for application in the IFMIF High Flux Test Module. ► Fabrication of prototypes of the irradiation capsules of the IFMIF High Flux Test Module. - Abstract: The international fusion materials irradiation facility (IFMIF) is projected to create an experimentally validated database of material properties relevant for fusion reactor designs. The IFMIF High Flux Test Module is the dedicated experiment to irradiate alloys in the temperature range 250–550 °C and up to 50 displacements per atom per irradiation cycle. The High Flux Test Module is developed to maximize the specimen payload in the restricted irradiation volume, and to minimize the temperature spread within each specimen bundle. Low pressure helium mini-channel cooling is used to offer a high integration density. Due to the demanding thermo-hydraulic and mechanical conditions, the engineering design process (involving numerical neutronic, thermo-hydraulic and mechanical analyses) is supported by extensive experimental validation activities. This paper reports on the prototype manufacturing, thermo-hydraulic modeling experiments and component tests, as well as on mechanical testing. For the testing of the 1:1 prototype of the High Flux Test Module, a dedicated test facility, the Helium Loop Karlsruhe-Low Pressure (HELOKA-LP) has been taken into service.

  2. Development of Novel High Temperature Superconducting Detectors Based on Flux Activation and Ultrafast Dynamics

    National Research Council Canada - National Science Library

    Frankel, Anatoly

    1998-01-01

    It is proposed to study quasiparticle (QP) relaxation dynamics and flux mechanism of HTS using pump/probe femtosecond spectroscopy and nonequilibrium photoresponse in the presence of a magnetic field (and/or bias current...

  3. Timing of electromyographic activity and ranges of motion during simple motor tasks of upper extremities

    Directory of Open Access Journals (Sweden)

    Syczewska Małgorzata

    2017-10-01

    Full Text Available Study aim: Improvement of the upper extremities’ performance is one of the key aims in the rehabilitation process. In order to achieve high effectiveness of this process the amount of functional improvement achieved by a patient during the therapy needs to be assessed. The aim of this study was to obtain electromyographic (EMG activity profiles of the upper extremity muscles during execution of simple tasks in healthy subjects. Additionally the ranges of wrist, elbow and shoulder joints were measured and reported during performed trials. The second aim was to determine whether the movement execution and ranges of move­ments and muscular activity depend on age. Material and methods: Twenty-eight healthy adults, age range 21 to 65 years old, participated in the study. Surface electrodes were placed bilaterally on 7 upper extremity muscles. To obtain information about the beginning and end of the movement task and ranges of upper extremity joints, 13 markers were placed on the elbows and wrists of both upper extremities. The move­ments of the segments were calculated (distal vs proximal in five simple functional tasks (each task involved only one joint, performed while sitting. Kinematic data were collected by the VICON 460 system, and electromyographic data with the Mo­tion Lab EMG system. Results: Charts of timing of EMG activity of the upper extremity muscles together with ranges of upper extremity joint motion were obtained. Conclusion: The results show that the number of muscles activated and the time (or percentage of the task during which they are active depend on the type of the task and age. These data can be used as a reference in evaluation of functional deficits of patients.

  4. Clustering of Emerging Flux

    Science.gov (United States)

    Ruzmaikin, A.

    1997-01-01

    Observations show that newly emerging flux tends to appear on the Solar surface at sites where there is flux already. This results in clustering of solar activity. Standard dynamo theories do not predict this effect.

  5. Measurement of thermal, epithermal and fast neutrons fluxes by the activation foil method at IEA-R1 reactor

    International Nuclear Information System (INIS)

    Dias, M.S.; Koskinas, M.F.; Berretta, J.R.; Fratin, L.; Botelho, S.

    1990-01-01

    The thermal, epithermal and fast neutron fluxes have been determined experimentally by the activation foil method at position GI, located near the IEA-R1 reactor core. The reactions used were 197 Au (n,gamma) 198 Au, for thermal and epithermal neutrons and 27 Na (n,alpha) 24 Na, for fast neutrons. The activities were measured by the 4π(PC)β-γ coincidence method. (author)

  6. Measuring radon flux across active faults: Relevance of excavating and possibility of satellite discharges

    Energy Technology Data Exchange (ETDEWEB)

    Richon, Patrick, E-mail: patrick.richon@cea.f [CEA, DAM, DIF, F-91297 Arpajon (France); Institut de Physique du Globe de Paris, Equipe Geologie des Systemes Volcaniques, 4 place Jussieu, UMR-7154 CNRS, F-75005 Paris (France); Klinger, Yann; Tapponnier, Paul [Institut de Physique du Globe de Paris, Equipe de Seismotectonique, 4 place Jussieu, UMR-7154 CNRS, F-75005 Paris (France); Li Chenxia [Institute of Geology, Chinese Earthquake Administration, P.O. Box 9803, 100029 Beijing (China); Van Der Woerd, Jerome [Institut de Physique du Globe de Strasbourg, CNRS, UMR-7516, INSU, Universite Louis Pasteur, Strasbourg I, 5 Rue Rene Descartes, F-67084 Strasbourg Cedex (France); Perrier, Frederic [Institut de Physique du Globe de Paris, Equipe de Geomagnetisme, 4 place Jussieu, UMR-7154 CNRS et Universite Paris 7 Denis-Diderot, F-75005 Paris (France)

    2010-02-15

    Searching for gas exhalation around major tectonic contacts raises important methodological issues such as the role of the superficial soil and the possible long distance transport. These effects have been studied on the Xidatan segment of the Kunlun Fault, Qinghai Province, China, using measurement of the radon-222 and carbon dioxide exhalation flux. A significant radon flux, reaching up to 538 +- 33 mBq m{sup -2} s{sup -1} was observed in a 2-3 m deep trench excavated across the fault. On the soil surface, the radon flux varied from 7 to 38 mBq m{sup -2} s{sup -1}, including on the fault trace, with an average value of 14.1 +- 1.0 mBq m{sup -2} s{sup -1}, similar to the world average. The carbon dioxide flux on the soil surface, with an average value of 12.9 +- 3.3 g m{sup -2} day{sup -1}, also remained similar to regular background values. It showed no systematic spatial variation up to a distance of 1 km from the fault, and no clear enhancement in the trench. However, a high carbon dioxide flux of 421 +- 130 g m{sup -2} day{sup -1} was observed near subvertical fractured phyllite outcrops on a hill located about 3 km north of the fault, at the boundary of the large-scale pull-apart basin associated with the fault. This high carbon dioxide flux was associated with a high radon flux of 607 +- 35 mBq m{sup -2} s{sup -1}. These preliminary results indicate that, at the fault trace, it can be important to measure gas flux at the bottom of a trench to remove superficial soil layers. In addition, gas discharges need to be investigated also at some distance from the main fault, in zones where morphotectonics features support associated secondary fractures.

  7. Design of an actively cooled plate calorimeter for the investigation of pool fire heat fluxes

    International Nuclear Information System (INIS)

    Koski, J.A.; Keltner, N.R.; Nicolette, V.F.; Wix, S.D.

    1992-01-01

    For final qualification of shipping containers for transport of hazardous materials, thermal testing in accordance with regulations such as 10CFR71 must be completed. Such tests typically consist of 30 minute exposures with the container fully engulfed in flames from a large, open pool of JP4 jet engine fuel. Despite careful engineering analyses of the container, testing often reveals design problems that must be solved by modification and expensive retesting of the container. One source of this problem is the wide variation in surface heat flux to the container that occurs in pool fires. Average beat fluxes of 50 to 60 kW/m 2 are typical and close the values implied by the radiation model in 10CFR71, but peak fluxes up to 150 kW/m 2 are routinely observed in fires (Keltner, et al,1990). Heat fluxes in pool fires have been shown to be a function of surface temperature of the container, height above the pool, surface orientation, wind, and other variables. If local variations in the surface heat flux to the container can be better predicted, design analyses will become more accurate, and fewer problems will be uncovered during testing. The objective of the calorimeter design described in this paper is to measure accurately pool fire heat fluxes under controlled conditions, and to provide data for calibration of improved analytical models of local flame-surface interactions

  8. Design of an actively cooled plate calorimeter for the investigation of pool fire heat fluxes

    International Nuclear Information System (INIS)

    Koski, J.A.; Keltner, N.R.; Nicolette, V.F.; Wix, S.D.

    1992-01-01

    For final qualification of shipping containers for transport of hazardous materials, thermal testing in accordance with regulations such as 10CFR71 must be completed. Such tests typically consist of 30 minute exposures with the container fully engulfed in flames from a large, open pool of JP4 jet engine fuel. Despite careful engineering analyses of the container, testing often reveals design problems that must be solved by modification and expensive retesting of the container. One source of this problem is the wide variation in surface heat flux to the container that occurs in pool fires. Average heat fluxes of 50 to 60 kW/m 2 are typical and close the values implied by the radiation model in 10CFR71, but peak fluxes up to 150 kW/m 2 are routinely observed in fires. Heat fluxes in pool fires have been shown to be a function of surface temperature of the container, height above the pool, surface orientation, wind, and other variables. If local variations in the surface heat flux to the container could be better predicted, design analyses would become more accurate, and fewer problems will be uncovered during testing. The objective of the calorimeter design described in this paper is to measure accurately pool fire heat fluxes under controlled conditions, and to provide data for calibration of improved analytical models of local flame-surface interactions

  9. Two-dimensional nature of the active Brownian motion of catalytic microswimmers at solid and liquid interfaces

    International Nuclear Information System (INIS)

    Dietrich, Kilian; Renggli, Damian; Zanini, Michele; Buttinoni, Ivo; Isa, Lucio; Volpe, Giovanni

    2017-01-01

    Colloidal particles equipped with platinum patches can establish chemical gradients in H 2 O 2 -enriched solutions and undergo self-propulsion due to local diffusiophoretic migration. In bulk (3D), this class of active particles swim in the direction of the surface heterogeneities introduced by the patches and consequently reorient with the characteristic rotational diffusion time of the colloids. In this article, we present experimental and numerical evidence that planar 2D confinements defy this simple picture. Instead, the motion of active particles both on solid substrates and at flat liquid–liquid interfaces is captured by a 2D active Brownian motion model, in which rotational and translational motion are constrained in the xy -plane. This leads to an active motion that does not follow the direction of the surface heterogeneities and to timescales of reorientation that do not match the free rotational diffusion times. Furthermore, 2D-confinement at fluid–fluid interfaces gives rise to a unique distribution of swimming velocities: the patchy colloids uptake two main orientations leading to two particle populations with velocities that differ up to one order of magnitude. Our results shed new light on the behavior of active colloids in 2D, which is of interest for modeling and applications where confinements are present. (paper)

  10. Cortical activation to object shape and speed of motion during the first year.

    Science.gov (United States)

    Wilcox, Teresa; Hawkins, Laura B; Hirshkowitz, Amy; Boas, David A

    2014-10-01

    A great deal is known about the functional organization of cortical networks that mediate visual object processing in the adult. The current research is part of a growing effort to identify the functional maturation of these pathways in the developing brain. The current research used near-infrared spectroscopy to investigate functional activation of the infant cortex during the processing of featural information (shape) and spatiotemporal information (speed of motion) during the first year of life. Our investigation focused on two areas that were implicated in previous studies: anterior temporal cortex and posterior parietal cortex. Neuroimaging data were collected with 207 infants across three age groups: 3-6 months (Experiment 1), 7-8 months (Experiment 2), and 10-12 months (Experiments 3 and 4). The neuroimaging data revealed age-related changes in patterns of activation to shape and speed information, mostly involving posterior parietal areas, some of which were predicted and others that were not. We suggest that these changes reflect age-related differences in the perceptual and/or cognitive processes engaged during the task. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Evolution of Muscle Activity Patterns Driving Motions of the Jaw and Hyoid during Chewing in Gnathostomes

    Science.gov (United States)

    Konow, Nicolai; Herrel, Anthony; Ross, Callum F.; Williams, Susan H.; German, Rebecca Z.; Sanford, Christopher P. J.; Gintof, Chris

    2011-01-01

    Although chewing has been suggested to be a basal gnathostome trait retained in most major vertebrate lineages, it has not been studied broadly and comparatively across vertebrates. To redress this imbalance, we recorded EMG from muscles powering anteroposterior movement of the hyoid, and dorsoventral movement of the mandibular jaw during chewing. We compared muscle activity patterns (MAP) during chewing in jawed vertebrate taxa belonging to unrelated groups of basal bony fishes and artiodactyl mammals. Our aim was to outline the evolution of coordination in MAP. Comparisons of activity in muscles of the jaw and hyoid that power chewing in closely related artiodactyls using cross-correlation analyses identified reorganizations of jaw and hyoid MAP between herbivores and omnivores. EMG data from basal bony fishes revealed a tighter coordination of jaw and hyoid MAP during chewing than seen in artiodactyls. Across this broad phylogenetic range, there have been major structural reorganizations, including a reduction of the bony hyoid suspension, which is robust in fishes, to the acquisition in a mammalian ancestor of a muscle sling suspending the hyoid. These changes appear to be reflected in a shift in chewing MAP that occurred in an unidentified anamniote stem-lineage. This shift matches observations that, when compared with fishes, the pattern of hyoid motion in tetrapods is reversed and also time-shifted relative to the pattern of jaw movement. PMID:21705368

  12. Altered Coupling between Motion-Related Activation and Resting-State Brain Activity in the Ipsilesional Sensorimotor Cortex after Cerebral Stroke

    Directory of Open Access Journals (Sweden)

    Jianping Hu

    2017-07-01

    Full Text Available Functional connectivity maps using resting-state functional magnetic resonance imaging (rs-fMRI can closely resemble task fMRI activation patterns, suggesting that resting-state brain activity may predict task-evoked activation or behavioral performance. However, this conclusion was mostly drawn upon a healthy population. It remains unclear whether the predictive ability of resting-state brain activity for task-evoked activation would change under different pathological conditions. This study investigated dynamic changes of coupling between patterns of resting-state functional connectivity (RSFC and motion-related activation in different stages of cerebral stroke. Twenty stroke patients with hand motor function impairment were involved. rs-fMRI and hand motion-related fMRI data were acquired in the acute, subacute, and early chronic stages of cerebral stroke on a 3-T magnetic resonance (MR scanner. Sixteen healthy participants were enrolled as controls. For each subject, an activation map of the affected hand was first created using general linear model analysis on task fMRI data, and then an RSFC map was determined by seeding at the peak region of hand motion activation during the intact hand task. We then measured the extent of coupling between the RSFC maps and motion-related activation maps. Dynamic changes of the coupling between the two fMRI maps were estimated using one-way repeated measures analysis of variance across the three stages. Moreover, imaging parameters were correlated with motor performances. Data analysis showed that there were different coupling patterns between motion-related activation and RSFC maps associating with the affected motor regions during the acute, subacute, and early chronic stages of stroke. Coupling strengths increased as the recovery from stroke progressed. Coupling strengths were correlated with hand motion performance in the acute stage, while coupling recovery was negatively correlated with the recovery

  13. Comparison between different flux traps assembled in the core of the nuclear reactor IPEN/MB-01 by measuring of the thermal and epithermal neutron fluxes using activation foils

    International Nuclear Information System (INIS)

    Mura, Luiz Ernesto Credidio; Bitelli, Ulysses d'Utra; Mura, Luis Felipe Liambos; Carluccio, Thiago; Andrade, Graciete Simoes de

    2011-01-01

    The production of radioisotopes is one of the most important applications of nuclear research reactors. This study investigated a method called Flux Trap, which is used to increase the yield of production of radioisotopes in nuclear reactors. The method consists in the rearrangement of the fuel rods to allow the increase of the thermal neutron flux in the irradiation region inside the reactor core, without changing the standard reactor power level. Various configurations were assembled with the objective of finding the configuration with the highest thermal neutron flux in the region of irradiation. The method of activation analysis was used to measure the thermal neutron flux and determine the most efficient reactor core configuration . It was found that there was an increase in the thermal neutron flux of 337% in the most efficient configuration, which demonstrates the effectiveness of the method. (author)

  14. Bioturbation and dissolved organic matter enhance contaminant fluxes from sediment treated with powdered and granular activated carbon.

    Science.gov (United States)

    Kupryianchyk, D; Noori, A; Rakowska, M I; Grotenhuis, J T C; Koelmans, A A

    2013-05-21

    Sediment amendment with activated carbon (AC) is a promising technique for in situ sediment remediation. To date it is not clear whether this technique sufficiently reduces sediment-to-water fluxes of sediment-bound hydrophobic organic chemicals (HOCs) in the presence of bioturbators. Here, we report polychlorobiphenyl (PCB) pore water concentrations, fluxes, mass transfer coefficients, and survival data of two benthic species, for four treatments: no AC addition (control), powdered AC addition, granular AC addition and addition and subsequent removal of GAC (sediment stripping). AC addition decreased mass fluxes but increased apparent mass transfer coefficients because of dissolved organic carbon (DOC) facilitated transport across the benthic boundary layer (BBL). In turn, DOC concentrations depended on bioturbator activity which was high for the PAC tolerant species Asellus aquaticus and low for AC sensitive species Lumbriculus variegatus. A dual BBL resistance model combining AC effects on gradients, DOC facilitated transport and biodiffusion was evaluated against the data and showed how the type of resistance differs with treatment and chemical hydrophobicity. Data and simulations illustrate the complex interplay between AC and contaminant toxicity to benthic organisms and how differences in species tolerance affect mass fluxes from sediment to the water column.

  15. Body mass index and active range of motion exercise treatment after intra-articular injection in adhesive capsulitis

    Directory of Open Access Journals (Sweden)

    Hsi-Hsien Lin

    2013-04-01

    Conclusion: Active range of motion exercise after an intra-articular injection of corticosteroid and lidocaine improved pain and functional outcome at 8 weeks in normal-weight (BMI < 25 kg/m2 patients with primary adhesive capsulitis. Manipulation under anesthesia may be considered a priority in overweight patients.

  16. Fluxes of methane and nitrogen oxides in various boreal mire ecosystems. Effects of land-use activities and environmental changes

    International Nuclear Information System (INIS)

    Martikainen, P.J.; Nykaenen, H.; Regina, K.; Alm, J.; Silvola, J.

    1996-01-01

    Atmospheric impact of peatlands is a sum of their gas fluxes. In contrast to carbon dioxide, peatlands are net sources for methane (CH 4 ). Methane is an end product in the anaerobic decomposition processes and it has greater capacity to absorb infrared radiation than carbon dioxide. Most of the data on the CH 4 release from northern peatlands is from North America. The total amount of methane released from wetlands is calculated to be 110 Tg yr -1 of which 34 percent (38 Tg yr -1 ) is estimated to be emitted from the northern peatlands. Peat with high content of nitrogen is a potential source for gaseous nitrogen oxides, i.e. nitrous oxide (N 2 O) and nitric oxide (NO). However, the importance of peatlands in producing these trace gases is poorly known. Nitrous oxide and nitric oxide are important components in the atmospheric chemistry and N 2 O also is an effective greenhouse gas. Land-use activities and environmental changes can affect the atmospheric impacts of peatlands by modifying their biogeochemistry. This article presents a short summary of the studies whose objectives were: (1) to measure fluxes of CH 4 and N 2 O on wide range of natural mires in Finland, (2) to study the short- and long-term changes in fluxes of CH 4 , N 2 O and NO on boreal peatlands after lowering their water table. Peatlands used for agriculture, forestry and peat mining were included in the studies. The results from mires drained for forestry may reflect the possible changes in the trace gas fluxes if water table will drop in the northern peatlands as a result of drier climate, (3) to study the effects of nitrogen load on the fluxes of CH 4 , N 2 O and NO, (4) to identify the microbiological processes important for the fluxes of N 2 O, NO and CH 4 , and to study the environmental factors regulating these microbial processes

  17. A Method for the neutron flux determination during the activation process

    International Nuclear Information System (INIS)

    Maayouf, R.M.A.; Khalil, M.I.

    2000-01-01

    The present work deals with an accurate method for determining the neutron flux coming out from a neutron source during the experimental measurements. Accordingly, a suitable detector, followed by preamplifier and amplifier, is connected to a data acquisition system designed specially for this purpose; and the number of neutrons detected during every sampling period is stored in the PC. The historical file can be used to compute the average or the integral flux during any time period; considering the detector efficiency, geometrical arrangement and the amplification gain

  18. Energetic performance is improved by specific activation of K+ fluxes through K(Ca) channels in heart mitochondria

    DEFF Research Database (Denmark)

    Aon, Miguel A; Cortassa, Sonia; Wei, An-Chi

    2009-01-01

    Mitochondrial volume regulation depends on K+ movement across the inner membrane and a mitochondrial Ca2+-dependent K+ channel (mitoK(Ca)) reportedly contributes to mitochondrial K+ uniporter activity. Here we utilize a novel K(Ca) channel activator, NS11021, to examine the role of mito...... similar nonspecific (toxin-insensitive) effects at high concentrations. The results indicate that activating K+ flux through mitoK(Ca) mediates a beneficial effect on energetics that depends on mitochondrial swelling with maintained DeltaPsi(m)....

  19. Determination of nitrogen in wheat flour through Activation analysis using Fast neutron flux of a Thermal nuclear reactor

    International Nuclear Information System (INIS)

    Ramirez G, T.

    1976-01-01

    In this work is done a technical study for determining Nitrogen (protein) and other elements in wheat flour Activation analysis, with Fast neutrons from a Thermal nuclear reactor. Initially it is given an introduction about the basic principles of the methods of analysis. Equipment used in Activation analysis and a brief description of the neutron source (Thermal nuclear reactor). The realized experiments for determining the flux form in the irradiation site, the half life of N-13 and the interferences due to the sample composition are included too. Finally, the obtained results by Activation and the Kjeldahl method are tabulated. (Author)

  20. MOJAVE. X. PARSEC-SCALE JET ORIENTATION VARIATIONS AND SUPERLUMINAL MOTION IN ACTIVE GALACTIC NUCLEI

    Energy Technology Data Exchange (ETDEWEB)

    Lister, M. L.; Richards, J. L. [Department of Physics, Purdue University, 525 Northwestern Avenue, West Lafayette, IN 47907 (United States); Aller, M. F.; Aller, H. D. [Department of Astronomy, University of Michigan, 817 Dennison Building, Ann Arbor, MI 48109 (United States); Homan, D. C. [Department of Physics, Denison University, Granville, OH 43023 (United States); Kellermann, K. I. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Kovalev, Y. Y. [Astro Space Center of Lebedev Physical Institute, Profsoyuznaya 84/32, 117997 Moscow (Russian Federation); Pushkarev, A. B.; Ros, E.; Savolainen, T., E-mail: mlister@purdue.edu [Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn (Germany)

    2013-11-01

    We describe the parsec-scale kinematics of 200 active galactic nucleus (AGN) jets based on 15 GHz Very Long Baseline Array (VLBA) data obtained between 1994 August 31 and 2011 May 1. We present new VLBA 15 GHz images of these and 59 additional AGNs from the MOJAVE and 2 cm Survey programs. Nearly all of the 60 most heavily observed jets show significant changes in their innermost position angle over a 12-16 yr interval, ranging from 10° to 150° on the sky, corresponding to intrinsic variations of ∼0.°5 to ∼2°. The BL Lac jets show smaller variations than quasars. Roughly half of the heavily observed jets show systematic position angle trends with time, and 20 show indications of oscillatory behavior. The time spans of the data sets are too short compared to the fitted periods (5-12 yr), however, to reliably establish periodicity. The rapid changes and large jumps in position angle seen in many cases suggest that the superluminal AGN jet features occupy only a portion of the entire jet cross section and may be energized portions of thin instability structures within the jet. We have derived vector proper motions for 887 moving features in 200 jets having at least five VLBA epochs. For 557 well-sampled features, there are sufficient data to additionally study possible accelerations. We find that the moving features are generally non-ballistic, with 70% of the well-sampled features showing either significant accelerations or non-radial motions. Inward motions are rare (2% of all features), are slow (<0.1 mas yr{sup –1}), are more prevalent in BL Lac jets, and are typically found within 1 mas of the unresolved core feature. There is a general trend of increasing apparent speed with distance down the jet for both radio galaxies and BL Lac objects. In most jets, the speeds of the features cluster around a characteristic value, yet there is a considerable dispersion in the distribution. Orientation variations within the jet cannot fully account for the

  1. Long-term kinematics and sediment flux of an active earthflow, Eel River, California

    Science.gov (United States)

    B. H. Mackey; J. J. Roering; J. A. McKean

    2009-01-01

    Although earthflows are the dominant erosion mechanism in many mountainous landscapes, estimates of long-term earthflow-driven sediment flux remain elusive because landslide displacement data are typically limited to contemporary time periods. Combining high-resolution topography from airborne LiDAR (light detection and ranging), total station surveying, orthorectified...

  2. A Study to Increase Weld Penetration in P91 Steel During TIG Welding by using Activating Fluxes

    Science.gov (United States)

    Singh, Akhilesh Kumar; Kumar, Mayank; Dey, Vidyut; Naresh Rai, Ram

    2017-08-01

    Activated Flux TIG (ATIG) welding is a unique joining process, invented at Paton Institute of electric welding in 1960. ATIG welding process is also known as flux zoned TIG (FZTIG). In this process, a thin layer of activating flux is applied along the line on the surface of the material where the welding is to be carries out. The ATIG process aids to increase the weld penetration in thick materials. Activating fluxes used in the literature show the use of oxides like TiO2, SiO2, Cr2O3, ZnO, CaO, Fe2O3, and MnO2 during welding of steels. In the present study, ATIG was carried out on P-91 steel. Though, Tungsten Inert Gas welding gives excellent quality welds, but the penetration obtained in such welding is still demanding. P91 steel which is ferritic steel is used in high temperature applications. As this steel is, generally, used in thick sections, fabrication of such structures with TIG welding is limited, due to its low depth of penetration. To increase the depth of penetration in P91while welding with ATIG, the role of various oxides were investigated. Apart from the oxides mentioned above, in the present study the role of B2O3, V2O5 and MgO, during ATIG welding of P91 was investigated. It was seen that, compared to TIG welding, there was phenomenal increase in weld penetration during ATIG welding. Amongst all the oxides used in this study, maximum penetration was achieved in case of B2O3. The measurements of weld penetration, bead width and heat affected zone of the weldings were carried out using an image analysis technique.

  3. The importance of using the mixed neutron flux in activation analysis of D-3He fueled reactors

    International Nuclear Information System (INIS)

    Khater, H.Y.; Sawan, M.E.

    1992-01-01

    This paper reports on the D-D and D-T secondary reactions in D- 3 He reactors which provide the neutron source term for most of the radioactivity produced in the structure of the reactor. radionuclides are produced as a result of neutron interactions with their parent nuclides. The amount of activity produced by any radionuclide depends on the number of its parent atoms present at any given time. One approach to account for the activity induced by both neutron sources in any activation analysis is to add their individual contributions. Performing two separate calculations for the D-D and D-T neutron flux components and adding their contributions yields conservative results due to underestimating the destruction of the parent atoms. The overestimation is more pronounced for short and intermediate lived nuclides, long operation time, large neutron flux and large destruction cross section for the parent atoms. In the steel first wall of a typical d- 3 He reactor, adding the individual contributions of the tow neutron sources results in overestimating the activities produced by most of the radioactive isotopes of Ag, Lu, Ta, W and Re. After 30 years of reactor operation, the activity of 187 W, which is a major source of safety concern in case of an accident, is more than an order of magnitude higher than its value if the mixed neutron flux is used. The activity of 188 Re, which is an important source of offsite does in case of accidental release, is overestimated by more than a factor of two

  4. Nitrogen determination in wheat by neutron activation analysis using fast neutron flux from a thermal nuclear reactor

    International Nuclear Information System (INIS)

    Ramirez G, T.

    1976-01-01

    This is a study of the technique for the determination of nitrogen and other elements in wheat flour through activation analysis with fast neutrons from a thermal nuclear reactor. The study begins with an introduction about the basis of the analytical methods, the equipment used in activation analysis and a brief description of the neutrons source. In the study are included the experiments carried out in order to determine the flux form in the site of irradiation, the N-13 half life and the interference due to the sample composition. (author)

  5. Interplanetary Magnetic Flux Ropes as Agents Connecting Solar Eruptions and Geomagnetic Activities

    Science.gov (United States)

    Marubashi, K.; Cho, K.-S.; Ishibashi, H.

    2017-12-01

    We investigate the solar wind structure for 11 cases that were selected for the campaign study promoted by the International Study of Earth-affecting Solar Transients (ISEST) MiniMax24 Working Group 4. We can identify clear flux rope signatures in nine cases. The geometries of the nine interplanetary magnetic flux ropes (IFRs) are examined with a model-fitting analysis with cylindrical and toroidal force-free flux rope models. For seven cases in which magnetic fields in the solar source regions were observed, we compare the IFR geometries with magnetic structures in their solar source regions. As a result, we can confirm the coincidence between the IFR orientation and the orientation of the magnetic polarity inversion line (PIL) for six cases, as well as the so-called helicity rule as regards the handedness of the magnetic chirality of the IFR, depending on which hemisphere of the Sun the IFR originated from, the northern or southern hemisphere; namely, the IFR has right-handed (left-handed) magnetic chirality when it is formed in the southern (northern) hemisphere of the Sun. The relationship between the orientation of IFRs and PILs can be taken as evidence that the flux rope structure created in the corona is in most cases carried through interplanetary space with its orientation maintained. In order to predict magnetic field variations on Earth from observations of solar eruptions, further studies are needed about the propagation of IFRs because magnetic fields observed at Earth significantly change depending on which part of the IFR hits the Earth.

  6. Strong ground motion prediction applying dynamic rupture simulations for Beppu-Haneyama Active Fault Zone, southwestern Japan

    Science.gov (United States)

    Yoshimi, M.; Matsushima, S.; Ando, R.; Miyake, H.; Imanishi, K.; Hayashida, T.; Takenaka, H.; Suzuki, H.; Matsuyama, H.

    2017-12-01

    We conducted strong ground motion prediction for the active Beppu-Haneyama Fault zone (BHFZ), Kyushu island, southwestern Japan. Since the BHFZ runs through Oita and Beppy cities, strong ground motion as well as fault displacement may affect much to the cities.We constructed a 3-dimensional velocity structure of a sedimentary basin, Beppu bay basin, where the fault zone runs through and Oita and Beppu cities are located. Minimum shear wave velocity of the 3d model is 500 m/s. Additional 1-d structure is modeled for sites with softer sediment: holocene plain area. We observed, collected, and compiled data obtained from microtremor surveys, ground motion observations, boreholes etc. phase velocity and H/V ratio. Finer structure of the Oita Plain is modeled, as 250m-mesh model, with empirical relation among N-value, lithology, depth and Vs, using borehole data, then validated with the phase velocity data obtained by the dense microtremor array observation (Yoshimi et al., 2016).Synthetic ground motion has been calculated with a hybrid technique composed of a stochastic Green's function method (for HF wave), a 3D finite difference (LF wave) and 1D amplification calculation. Fault geometry has been determined based on reflection surveys and active fault map. The rake angles are calculated with a dynamic rupture simulation considering three fault segments under a stress filed estimated from source mechanism of earthquakes around the faults (Ando et al., JpGU-AGU2017). Fault parameters such as the average stress drop, a size of asperity etc. are determined based on an empirical relation proposed by Irikura and Miyake (2001). As a result, strong ground motion stronger than 100 cm/s is predicted in the hanging wall side of the Oita plain.This work is supported by the Comprehensive Research on the Beppu-Haneyama Fault Zone funded by the Ministry of Education, Culture, Sports, Science, and Technology (MEXT), Japan.

  7. Activity-dependent branching ratios in stocks, solar x-ray flux, and the Bak-Tang-Wiesenfeld sandpile model

    Science.gov (United States)

    Martin, Elliot; Shreim, Amer; Paczuski, Maya

    2010-01-01

    We define an activity-dependent branching ratio that allows comparison of different time series Xt . The branching ratio bx is defined as bx=E[ξx/x] . The random variable ξx is the value of the next signal given that the previous one is equal to x , so ξx={Xt+1∣Xt=x} . If bx>1 , the process is on average supercritical when the signal is equal to x , while if bxmarket hypothesis.” For stock volumes, solar x-ray flux intensities, and the Bak-Tang-Wiesenfeld (BTW) sandpile model, bx is supercritical for small values of activity and subcritical for the largest ones, indicating a tendency to return to a typical value. For stock volumes this tendency has an approximate power-law behavior. For solar x-ray flux and the BTW model, there is a broad regime of activity where bx≃1 , which we interpret as an indicator of critical behavior. This is true despite different underlying probability distributions for Xt and for ξx . For the BTW model the distribution of ξx is Gaussian, for x sufficiently larger than 1, and its variance grows linearly with x . Hence, the activity in the BTW model obeys a central limit theorem when sampling over past histories. The broad region of activity where bx is close to one disappears once bulk dissipation is introduced in the BTW model—supporting our hypothesis that it is an indicator of criticality.

  8. Interpretation of scrape-off layer profile evolution and first-wall ion flux statistics on JET using a stochastic framework based on fillamentary motion

    Science.gov (United States)

    Walkden, N. R.; Wynn, A.; Militello, F.; Lipschultz, B.; Matthews, G.; Guillemaut, C.; Harrison, J.; Moulton, D.; Contributors, JET

    2017-08-01

    This paper presents the use of a novel modelling technique based around intermittent transport due to filament motion, to interpret experimental profile and fluctuation data in the scrape-off layer (SOL) of JET during the onset and evolution of a density profile shoulder. A baseline case is established, prior to shoulder formation, and the stochastic model is shown to be capable of simultaneously matching the time averaged profile measurement as well as the PDF shape and autocorrelation function from the ion-saturation current time series at the outer wall. Aspects of the stochastic model are then varied with the aim of producing a profile shoulder with statistical measurements consistent with experiment. This is achieved through a strong localised reduction in the density sink acting on the filaments within the model. The required reduction of the density sink occurs over a highly localised region with the timescale of the density sink increased by a factor of 25. This alone is found to be insufficient to model the expansion and flattening of the shoulder region as the density increases, which requires additional changes within the stochastic model. An example is found which includes both a reduction in the density sink and filament acceleration and provides a consistent match to the experimental data as the shoulder expands, though the uniqueness of this solution can not be guaranteed. Within the context of the stochastic model, this implies that the localised reduction in the density sink can trigger shoulder formation, but additional physics is required to explain the subsequent evolution of the profile.

  9. Calculation of heat fluxes induced by radio frequency heating on the actively cooled protections of ion cyclotron resonant heating (ICRH) and lower hybrid (LH) antennas in Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Ritz, G., E-mail: Guillaume.ritz@gmail.com [CEA, Institut de la Recherche sur la Fusion Magnétique (IRFM), 13108 Saint Paul-lez-Durance (France); Corre, Y., E-mail: Yann.corre@cea.fr [CEA, Institut de la Recherche sur la Fusion Magnétique (IRFM), 13108 Saint Paul-lez-Durance (France); Rault, M.; Missirlian, M. [CEA, Institut de la Recherche sur la Fusion Magnétique (IRFM), 13108 Saint Paul-lez-Durance (France); Portafaix, C. [ITER Organization, Route de Vinon-sur-Verdon, 13115 Saint Paul-lez-Durance (France); Martinez, A.; Ekedahl, A.; Colas, L.; Guilhem, D.; Salami, M.; Loarer, T. [CEA, Institut de la Recherche sur la Fusion Magnétique (IRFM), 13108 Saint Paul-lez-Durance (France)

    2013-10-15

    Highlights: ► The heat flux generated by radiofrequency (RF) heating was calculated using Tore Supra's heating antennas. ► The highest heat flux value, generated by ions accelerated in RF-rectified sheath potentials, was 5 MW/m{sup 2}. ► The heat flux on the limiters of antennas was in the same order of magnitude as that on the toroidal pumping limiter. -- Abstract: Lower hybrid current drive (LHCD) and ion cyclotron resonance heating (ICRH) are recognized as important auxiliary heating and current drive methods for present and next step fusion devices. However, these radio frequency (RF) systems generate a heat flux up to several MW/m{sup 2} on the RF antennas during plasma operation. This paper focuses on the determination of the heat flux deposited on the lateral protections of the RF antennas in Tore Supra. The heat flux was calculated by finite element method (FEM) using a model of the lateral protection. The FEM calculation was based on surface temperature measurements using infrared cameras monitoring the RF antennas. The heat flux related to the acceleration of electrons in front of the LHCD grills (LHCD active) and to the acceleration of ions in RF-rectified sheath potentials (ICRH active) were calculated. Complementary results on the heat flux related to fast ions (ICRH active with a relatively low magnetic field) are also reported in this paper.

  10. Fluxes of methane and nitrogen oxides in various boreal mire ecosystems. Effects of land-use activities and environmental changes

    Energy Technology Data Exchange (ETDEWEB)

    Martikainen, P.J.; Nykaenen, H.; Regina, K. [National Public Health Inst., Kuopio (Finland). Lab. of Environmental Microbiology; Alm, J.; Silvola, J. [Joensuu Univ. (Finland). Dept. of Biology

    1996-12-31

    Atmospheric impact of peatlands is a sum of their gas fluxes. In contrast to carbon dioxide, peatlands are net sources for methane (CH{sub 4}). Methane is an end product in the anaerobic decomposition processes and it has greater capacity to absorb infrared radiation than carbon dioxide. Most of the data on the CH{sub 4} release from northern peatlands is from North America. The total amount of methane released from wetlands is calculated to be 110 Tg yr{sup -1} of which 34 percent (38 Tg yr{sup -1}) is estimated to be emitted from the northern peatlands. Peat with high content of nitrogen is a potential source for gaseous nitrogen oxides, i.e. nitrous oxide (N{sub 2}O) and nitric oxide (NO). However, the importance of peatlands in producing these trace gases is poorly known. Nitrous oxide and nitric oxide are important components in the atmospheric chemistry and N{sub 2}O also is an effective greenhouse gas. Land-use activities and environmental changes can affect the atmospheric impacts of peatlands by modifying their biogeochemistry. This article presents a short summary of the studies whose objectives were: (1) to measure fluxes of CH{sub 4} and N{sub 2}O on wide range of natural mires in Finland, (2) to study the short- and long-term changes in fluxes of CH{sub 4}, N{sub 2}O and NO on boreal peatlands after lowering their water table. Peatlands used for agriculture, forestry and peat mining were included in the studies. The results from mires drained for forestry may reflect the possible changes in the trace gas fluxes if water table will drop in the northern peatlands as a result of drier climate, (3) to study the effects of nitrogen load on the fluxes of CH{sub 4}, N{sub 2}O and NO, (4) to identify the microbiological processes important for the fluxes of N{sub 2}O, NO and CH{sub 4}, and to study the environmental factors regulating these microbial processes

  11. Fluxes of methane and nitrogen oxides in various boreal mire ecosystems. Effects of land-use activities and environmental changes

    Energy Technology Data Exchange (ETDEWEB)

    Martikainen, P J; Nykaenen, H; Regina, K [National Public Health Inst., Kuopio (Finland). Lab. of Environmental Microbiology; Alm, J; Silvola, J [Joensuu Univ. (Finland). Dept. of Biology

    1997-12-31

    Atmospheric impact of peatlands is a sum of their gas fluxes. In contrast to carbon dioxide, peatlands are net sources for methane (CH{sub 4}). Methane is an end product in the anaerobic decomposition processes and it has greater capacity to absorb infrared radiation than carbon dioxide. Most of the data on the CH{sub 4} release from northern peatlands is from North America. The total amount of methane released from wetlands is calculated to be 110 Tg yr{sup -1} of which 34 percent (38 Tg yr{sup -1}) is estimated to be emitted from the northern peatlands. Peat with high content of nitrogen is a potential source for gaseous nitrogen oxides, i.e. nitrous oxide (N{sub 2}O) and nitric oxide (NO). However, the importance of peatlands in producing these trace gases is poorly known. Nitrous oxide and nitric oxide are important components in the atmospheric chemistry and N{sub 2}O also is an effective greenhouse gas. Land-use activities and environmental changes can affect the atmospheric impacts of peatlands by modifying their biogeochemistry. This article presents a short summary of the studies whose objectives were: (1) to measure fluxes of CH{sub 4} and N{sub 2}O on wide range of natural mires in Finland, (2) to study the short- and long-term changes in fluxes of CH{sub 4}, N{sub 2}O and NO on boreal peatlands after lowering their water table. Peatlands used for agriculture, forestry and peat mining were included in the studies. The results from mires drained for forestry may reflect the possible changes in the trace gas fluxes if water table will drop in the northern peatlands as a result of drier climate, (3) to study the effects of nitrogen load on the fluxes of CH{sub 4}, N{sub 2}O and NO, (4) to identify the microbiological processes important for the fluxes of N{sub 2}O, NO and CH{sub 4}, and to study the environmental factors regulating these microbial processes

  12. Parkinson-Related Changes of Activation in Visuomotor Brain Regions during Perceived Forward Self-Motion

    NARCIS (Netherlands)

    van der Hoorn, Anouk; Renken, Remco J.; Leenders, Klaus L.; de Jong, Bauke M.

    2014-01-01

    Radial expanding optic flow is a visual consequence of forward locomotion. Presented on screen, it generates illusionary forward self-motion, pointing at a close vision-gait interrelation. As particularly parkinsonian gait is vulnerable to external stimuli, effects of optic flow on motor-related

  13. Epithermal neutron flux characterization of the TRIGA Mark III reactor, Salazar, Mexico, for use in Internal Neutron Activation Analysis

    International Nuclear Information System (INIS)

    Diaz Rizo, O.; Herrera Peraza, E.

    1996-01-01

    The non ideality of the epithermal neutron flux distribution at a reactor site parameter (made, using Chloramine-T method. Radiochemical purity and stability of the labelled product were determined by radiochromatography. The labelled Melagenine-II showed two radioactive fractions thermal-to-epithermal neutron ratio (f) were determined in the 3 typical irradiations positions of the TRIGA Mark III reactor of the National Nuclear Research Institute, Salazar, Mexico, using the Cd-ratio for multi monitor and bare bi-isotopic monitor methods respectively. This characterization is of use in the K o - method of neutron activation analysis, recently introduced at the Institute

  14. Active-Flux-Based, V/f-with-Stabilizing-Loops Versus Sensorless Vector Control of IPMSM Drives

    DEFF Research Database (Denmark)

    Moldovan, Ana; Blaabjerg, Frede; Boldea, Ion

    2011-01-01

    . By this control strategy, a fast dynamic speed response, without steady state error and without speed or current regulators, for all AC machines is obtained. The second control method is a sensorless vector control strategy which also has been implemented and tested, just for comparison.......This paper proposes two control methods for Interior Permanent Magnet Synchronous Motor (IPMSM) Drives. The first one is a V/f control with two stabilizing loops: one loop based on active flux balance for voltage magnitude correction and a second, based on speed error, with voltage phase correction...

  15. [Effects of brackish water irrigation on soil enzyme activity, soil CO2 flux and organic matter decomposition].

    Science.gov (United States)

    Zhang, Qian-qian; Wang, Fei; Liu, Tao; Chu, Gui-xin

    2015-09-01

    Brackish water irrigation utilization is an important way to alleviate water resource shortage in arid region. A field-plot experiment was set up to study the impact of the salinity level (0.31, 3.0 or 5.0 g · L(-1) NaCl) of irrigated water on activities of soil catalase, invertase, β-glucosidase, cellulase and polyphenoloxidase in drip irrigation condition, and the responses of soil CO2 flux and organic matter decomposition were also determined by soil carbon dioxide flux instrument (LI-8100) and nylon net bag method. The results showed that in contrast with fresh water irrigation treatment (CK), the activities of invertase, β-glucosidase and cellulase in the brackish water (3.0 g · L(-1)) irrigation treatment declined by 31.7%-32.4%, 29.7%-31.6%, 20.8%-24.3%, respectively, while soil polyphenoloxidase activity was obviously enhanced with increasing the salinity level of irrigated water. Compared to CK, polyphenoloxidase activity increased by 2.4% and 20.5%, respectively, in the brackish water and saline water irrigation treatments. Both soil microbial biomass carbon and microbial quotient decreased with increasing the salinity level, whereas, microbial metabolic quotient showed an increasing tendency with increasing the salinity level. Soil CO2 fluxes in the different treatments were in the order of CK (0.31 g · L(-1)) > brackish water irrigation (3.0 g · L(-1)) ≥ saline water irrigation (5.0 g · L(-1)). Moreover, CO2 flux from plastic film mulched soil was always much higher than that from no plastic film mulched soil, regardless the salinity of irrigated water. Compared with CK, soil CO2 fluxes in the saline water and brackish water treatments decreased by 29.8% and 28.2% respectively in the boll opening period. The decomposition of either cotton straw or alfalfa straw in the different treatments was in the sequence of CK (0.31 g · L(-1)) > brackish water irrigation (3.0 g · L(-1)) > saline water treatment (5.0 g · L(-1)). The organic matter

  16. Multi-pulse chaotic motions of a rotor-active magnetic bearing system with time-varying stiffness

    International Nuclear Information System (INIS)

    Zhang, W.; Yao, M.H.; Zhan, X.P.

    2006-01-01

    In this paper, we investigate the Shilnikov type multi-pulse chaotic dynamics for a rotor-active magnetic bearings (AMB) system with 8-pole legs and the time-varying stiffness. The stiffness in the AMB is considered as the time-varying in a periodic form. The dimensionless equation of motion for the rotor-AMB system with the time-varying stiffness in the horizontal and vertical directions is a two-degree-of-freedom nonlinear system with quadratic and cubic nonlinearities and parametric excitation. The asymptotic perturbation method is used to obtain the averaged equations in the case of primary parametric resonance and 1/2 subharmonic resonance. It is found from the numerical results that there are the phenomena of the Shilnikov type multi-pulse chaotic motions for the rotor-AMB system. A new jumping phenomenon is discovered in the rotor-AMB system with the time-varying stiffness

  17. Superfine powdered activated carbon (S-PAC) coatings on microfiltration membranes: Effects of milling time on contaminant removal and flux.

    Science.gov (United States)

    Amaral, Pauline; Partlan, Erin; Li, Mengfei; Lapolli, Flavio; Mefford, O Thompson; Karanfil, Tanju; Ladner, David A

    2016-09-01

    In microfiltration processes for drinking water treatment, one method of removing trace contaminants is to add powdered activated carbon (PAC). Recently, a version of PAC called superfine PAC (S-PAC) has been under development. S-PAC has a smaller particle size and thus faster adsorption kinetics than conventionally sized PAC. Membrane coating performance of various S-PAC samples was evaluated by measuring adsorption of atrazine, a model micropollutant. S-PACs were created in-house from PACs of three different materials: coal, wood, and coconut shell. Milling time was varied to produce S-PACs pulverized with different amounts of energy. These had different particles sizes, but other properties (e.g. oxygen content), also differed. In pure water the coal based S-PACs showed superior atrazine adsorption; all milled carbons had over 90% removal while the PAC had only 45% removal. With addition of calcium and/or NOM, removal rates decreased, but milled carbons still removed more atrazine than PAC. Oxygen content and specific external surface area (both of which increased with longer milling times) were the most significant predictors of atrazine removal. S-PAC coatings resulted in loss of filtration flux compared to an uncoated membrane and smaller particles caused more flux decline than larger particles; however, the data suggest that NOM fouling is still more of a concern than S-PAC fouling. The addition of calcium improved the flux, especially for the longer-milled carbons. Overall the data show that when milling S-PAC with different levels of energy there is a tradeoff: smaller particles adsorb contaminants better, but cause greater flux decline. Fortunately, an acceptable balance may be possible; for example, in these experiments the coal-based S-PAC after 30 min of milling achieved a fairly high atrazine removal (overall 80%) with a fairly low flux reduction (under 30%) even in the presence of NOM. This suggests that relatively short duration (low energy

  18. The spectral analysis of motion: An "open field" activity test example

    Directory of Open Access Journals (Sweden)

    Obradović Z.

    2013-01-01

    Full Text Available In this work we have described the new mathematical approach, with spectral analysis of the data to evaluate position and motion in the „„open field““ experiments. The aim of this work is to introduce several new parameters mathematically derived from experimental data by means of spectral analysis, and to quantitatively estimate the quality of the motion. Two original software packages (TRACKER and POSTPROC were used for transforming a video data to a log file, suitable for further computational analysis, and to perform analysis from the log file. As an example, results obtained from the experiments with Wistar rats in the „open field“ test are included. The test group of animals was treated with diazepam. Our results demonstrate that all the calculated parameters, such as movement variability, acceleration and deceleration, were significantly lower in the test group compared to the control group. We believe that the application of parameters obtained by spectral analysis could be of great significance in assessing the locomotion impairment in any kind of motion. [Projekat Ministarstva nauke Republike Srbije, br. III41007 i br. ON174028

  19. Pre-coincidence brain activity predicts the perceptual outcome of streaming/bouncing motion display.

    Science.gov (United States)

    Zhao, Song; Wang, Yajie; Jia, Lina; Feng, Chengzhi; Liao, Yu; Feng, Wenfeng

    2017-08-18

    When two identical visual discs move toward each other on a two-dimensional visual display, they can be perceived as either "streaming through" or "bouncing off" each other after their coincidence. Previous studies have observed a strong bias toward the streaming percept. Additionally, the incidence of the bouncing percept in this ambiguous display could be increased by various factors, such as a brief sound at the moment of coincidence and a momentary pause of the two discs. The streaming/bouncing bistable motion phenomenon has been studied intensively since its discovery. However, little is known regarding the neural basis underling the perceptual ambiguity in the classic version of the streaming/bouncing motion display. The present study investigated the neural basis of the perception disambiguating underling the processing of the streaming/bouncing bistable motion display using event-related potential (ERP) recordings. Surprisingly, the amplitude of frontal central P2 (220-260 ms) that was elicited by the moving discs ~200 ms before the coincidence of the two discs was observed to be predictive of subsequent streaming or bouncing percept. A larger P2 amplitude was observed for streaming percept than the bouncing percept. These findings suggest that the streaming/bouncing bistable perception may have been disambiguated unconsciously ~200 ms before the coincidence of the two discs.

  20. Co-factor engineering in lactobacilli: Effects of uncoupled ATPase activity on metabolic fluxes in Lactobacillus (L.) plantarum and L. sakei

    DEFF Research Database (Denmark)

    Rud, Ida; Solem, Christian; Jensen, Peter Ruhdal

    2008-01-01

    The hydrolytic F-1-part of the F1F0-ATPase was over-expressed in Lactobacillus (L.) plantarum NC8 and L. sakei Lb790x during fermentation of glucose or ribose, in order to study how changes in the intracellular levels of ATP and ADP affect the metabolic fluxes. The uncoupled ATPase activity...... resulted in a decrease in intracellular energy level (ATP/ADP ratio), biomass yield and growth rate. Interestingly, the glycolytic and ribolytic flux increased in L. plantarum with uncoupled ATPase activity compared to the reference strain by up to 20% and 50%, respectively. The ATP demand was estimated...... to have approximately 80% control on both the glycolytic and ribolytic flux in L. plantarum under these conditions. In contrast, the glycolytic and ribolytic flux decreased in L. sakei with uncoupled ATPase activity. (C) 2008 Elsevier Inc. All rights reserved....

  1. Graphene oxide quantum dots disrupt autophagic flux by inhibiting lysosome activity in GC-2 and TM4 cell lines

    International Nuclear Information System (INIS)

    Ji, Xiaoli; Xu, Bo; Yao, Mengmeng; Mao, Zhilei; Zhang, Yuqing; Xu, Guofeng; Tang, Qiusha; Wang, Xinru; Xia, Yankai

    2016-01-01

    Graphene oxide quantum dots (GOQDs) have broad application prospects in many areas including bioimaging, drug delivery, DNA cleavage system, sensors and photocatalyst. Recently, increasing concerns have been raised about their biocompatibility, but studies about the effects of GOQDs on male reproductive system are still lacking. In this work, we explored the effects and molecular mechanisms of GOQDs on GC-2 and TM4 cells. We found autophagosome accumulation in GC-2 and TM4 cells after GOQDs treatment. Both LC3-II/LC3-I ratio and p62 levels increased, and the chloroquine-induced accumulation of LC3-II didn’t enhance in the presence of GOQDs, which indicated that GOQDs blocked autophagic flux. Further studies found that the fusion between autophagosome and lysosome was not inhibited by GOQDs, but the proteolytic capacity of lysosome was weakened and both the expression and activity of cathepsin B reduced. Taken together, these results suggested that GOQDs blocked autophagic flux by decreasing the amount and enzymatic activity of cathepsin B and inhibiting lysosome proteolytic capacity in GC-2 and TM4 cells, which might have a potential hazard to male reproduction.

  2. The retraction of the protoplast during PCD is an active, and interruptible, calcium-flux driven process.

    Science.gov (United States)

    Kacprzyk, Joanna; Brogan, Niall P; Daly, Cara T; Doyle, Siamsa M; Diamond, Mark; Molony, Elizabeth M; McCabe, Paul F

    2017-07-01

    The protoplast retracts during apoptosis-like programmed cell death (AL-PCD) and, if this retraction is an active component of AL-PCD, it should be used as a defining feature for this type of programmed cell death. We used an array of pharmacological and genetic tools to test if the rates of protoplast retraction in cells undergoing AL-PCD can be modulated. Disturbing calcium flux signalling, ATP synthesis and mitochondrial permeability transition all inhibited protoplast retraction and often also the execution of the death programme. Protoplast retraction can precede loss of plasma membrane integrity and cell death can be interrupted after the protoplast retraction had already occurred. Blocking calcium influx inhibited the protoplast retraction, reduced DNA fragmentation and delayed death induced by AL-PCD associated stresses. At higher levels of stress, where cell death occurs without protoplast retraction, blocking calcium flux had no effect on the death process. The results therefore strongly suggest that retraction of the protoplast is an active biological process dependent on an early Ca 2+ -mediated trigger rather than cellular disintegration due to plasma membrane damage. Therefore this morphologically distinct cell type is a quantifiable feature, and consequently, reporter of AL-PCD. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Activity-dependent branching ratios in stocks, solar x-ray flux, and the Bak-Tang-Wiesenfeld sandpile model.

    Science.gov (United States)

    Martin, Elliot; Shreim, Amer; Paczuski, Maya

    2010-01-01

    We define an activity-dependent branching ratio that allows comparison of different time series X(t). The branching ratio b(x) is defined as b(x)=E[xi(x)/x]. The random variable xi(x) is the value of the next signal given that the previous one is equal to x, so xi(x)=[X(t+1) | X(t)=x]. If b(x)>1, the process is on average supercritical when the signal is equal to x, while if b(x)efficient market hypothesis." For stock volumes, solar x-ray flux intensities, and the Bak-Tang-Wiesenfeld (BTW) sandpile model, b(x) is supercritical for small values of activity and subcritical for the largest ones, indicating a tendency to return to a typical value. For stock volumes this tendency has an approximate power-law behavior. For solar x-ray flux and the BTW model, there is a broad regime of activity where b(x) approximately equal 1, which we interpret as an indicator of critical behavior. This is true despite different underlying probability distributions for X(t) and for xi(x). For the BTW model the distribution of xi(x) is Gaussian, for x sufficiently larger than 1, and its variance grows linearly with x. Hence, the activity in the BTW model obeys a central limit theorem when sampling over past histories. The broad region of activity where b(x) is close to one disappears once bulk dissipation is introduced in the BTW model-supporting our hypothesis that it is an indicator of criticality.

  4. Controls on gross fluxes of nitrous oxide and methane from an active agricultural ecosystem

    Science.gov (United States)

    Yang, W. H.; Silver, W. L.

    2013-12-01

    Agricultural soils can be a significant source of greenhouse gas emissions. Most research on the dynamics of these gases measure net fluxes across the soil-atmosphere interface. This approach limits our ability to determine driving variables because production and consumption processes occur simultaneously, and may be controlled by different factors. We used the trace gas stable isotope pool dilution technique to simultaneously measure field rates of gross production and consumption of N2O and CH4 during the growing season in a corn field located in the Sacramento-San Joaquin Delta, California. We also measured net nitrogen (N) mineralization and nitrification rates, soil temperature, soil moisture, and soil carbon dioxide (CO2) emissions to explore their role as drivers of greenhouse gas fluxes. Across five sampling dates spanning from seeding to senescence, net N2O fluxes ranged from 0 - 4.5 mg N m-2 d-1 and averaged 1.6 × 0.2 mg N m-2 d-1 (n = 112). Gross N2O production ranged from 0.09 - 6.6 mg N m-2 d-1 and gross N2O reduction rates ranged from 0.00 - 0.95 mg N m-2 d-1. The N2O yield averaged 0.68 × 0.02 (n = 40). At peak growth (days after seeding 59 and 94), 89 % of the variability in gross N2O production rates was predicted by the combination of soil moisture, soil temperature, net N mineralization, and CO2 emissions (n = 15, p seeding 11, 24, and 171), gross N2O production was most strongly correlated with soil temperature (R2 = 0.20, n = 24, p = 0.03), and gross N2O reduction rates were best predicted by CO2 emissions (R2 = 0.80, n =24, p production in 36 out of 37 measurements. Gross CH4 production reached as high as 5.4 mg C m-2 d-1 with rates trending higher throughout the growing season. Gross CH4 production rates were marginally significantly higher in rows than in inter-rows (p = 0.10). Gross CH4 oxidation did not differ significantly among sampling dates (Figure 2b), averaging 1.1 × 0.2 mg C m-2 d-1 across all measurements (n = 37). However

  5. Design and damping force characterization of a new magnetorheological damper activated by permanent magnet flux dispersion

    Science.gov (United States)

    Lee, Tae-Hoon; Han, Chulhee; Choi, Seung-Bok

    2018-01-01

    This work proposes a novel type of tunable magnetorheological (MR) damper operated based solely on the location of a permanent magnet incorporated into the piston. To create a larger damping force variation in comparison with the previous model, a different design configuration of the permanent-magnet-based MR (PMMR) damper is introduced to provide magnetic flux dispersion in two magnetic circuits by utilizing two materials with different magnetic reluctance. After discussing the design configuration and some advantages of the newly designed mechanism, the magnetic dispersion principle is analyzed through both the formulated analytical model of the magnetic circuit and the computer simulation based on the magnetic finite element method. Sequentially, the principal design parameters of the damper are determined and fabricated. Then, experiments are conducted to evaluate the variation in damping force depending on the location of the magnet. It is demonstrated that the new design and magnetic dispersion concept are valid showing higher damping force than the previous model. In addition, a curved structure of the two materials is further fabricated and tested to realize the linearity of the damping force variation.

  6. Manufacturing and thermomechanical testing of actively cooled all beryllium high heat flux test pieces

    International Nuclear Information System (INIS)

    Vasiliev, N.N.; Sokolov, Yu.A.; Shatalov, G.E.

    1995-01-01

    One of the problems affiliated to ITER high heat flux elements development is a problem of interface of beryllium protection with heat sink routinely made of copper alloys. To get rid of this problem all beryllium elements could be used as heat receivers in places of enhanced thermal loads. In accordance with this objectives four beryllium test pieces of two types have been manufactured in open-quotes Institute of Berylliumclose quotes for succeeding thermomechanical testing. Two of them were manufactured in accordance with JET team design; they are round open-quotes hypervapotron typeclose quotes test pieces. Another two ones are rectangular test sections with a twisted tape installed inside of the circular channel. Preliminary stress-strain analysis have been performed for both type of the test pieces. Hypervapotrons have been shipped to JET where they were tested on JET test bed. Thermomechanical testing of pieces of the type of open-quotes swirl tape inside of tubeclose quotes have been performed on Kurchatov Institute test bed. Chosen beryllium grade properties, some details of manufacturing, results of preliminary stress-strain analysis and thermomechanical testing of the test pieces open-quotes swirl tape inside of tubeclose quotes type are given in this report

  7. Using motion-sensor camera technology to infer seasonal activity and thermal niche of the desert tortoise (Gopherus agassizii)

    Science.gov (United States)

    Agha, Mickey; Augustine, Benjamin; Lovich, Jeffrey E.; Delaney, David F.; Sinervo, Barry; Murphy, Mason O.; Ennen, Joshua R.; Briggs, Jessica R.; Cooper, Robert J.; Price, Steven J.

    2015-01-01

    Understanding the relationships between environmental variables and wildlife activity is an important part of effective management. The desert tortoise (Gopherus agassizii), an imperiled species of arid environments in the southwest US, may have increasingly restricted windows for activity due to current warming trends. In summer 2013, we deployed 48 motion sensor cameras at the entrances of tortoise burrows to investigate the effects of temperature, sex, and day of the year on the activity of desert tortoises. Using generalized estimating equations, we found that the relative probability of activity was associated with temperature (linear and quadratic), sex, and day of the year. Sex effects showed that male tortoises are generally more active than female tortoises. Temperature had a quadratic effect, indicating that tortoise activity was heightened at a range of temperatures. In addition, we found significant support for interactions between sex and day of the year, and sex and temperature as predictors of the probability of activity. Using our models, we were able to estimate air temperatures and times (days and hours) that were associated with maximum activity during the study. Because tortoise activity is constrained by environmental conditions such as temperature, it is increasingly vital to conduct studies on how tortoises vary their activity throughout the Sonoran Desert to better understand the effects of a changing climate.

  8. Global N Cycle: Fluxes and N2O Mixing Ratios Originating from Human Activity

    Data.gov (United States)

    National Aeronautics and Space Administration — Nitrogen is a major nutrient in terrestrial ecosystems and an important catalyst in tropospheric photochemistry. Over the last century human activities have...

  9. Global N Cycle: Fluxes and N2O Mixing Ratios Originating from Human Activity

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: Nitrogen is a major nutrient in terrestrial ecosystems and an important catalyst in tropospheric photochemistry. Over the last century human activities...

  10. Study on electron fluxes with Esub(e)=40-500 keV in quiet periods of solar activity by means of correlation and spectral analysis technique

    International Nuclear Information System (INIS)

    Zel'dovich, M.A.; Trebukhovskaya, G.A.

    1982-01-01

    Background fluxes of low-energy electrons (Esub(e)=40-500 keV), observed in the interplanetary space in the absence of solar cosmic ray flares using the ''Prognoz-3'' artificial satellite during 1973-1974, are under study. Fluctuation power spectra and correlation functions of simultaneous series of fluxes of above electrons, galactic cosmic rays are calculated along with some parameters characterizing solar activity and interplanetary medium state. The mentioned analysis points to possible solar origin of background low-energy electron fluxes

  11. Semi-active Control of Shallow Cables with Magnetorheological Dampers under Harmonic Axial Support Motion

    DEFF Research Database (Denmark)

    Zhou, Q.; Nielsen, Søren R.K.; Qu, W.L.

    2007-01-01

    amplitude is located in a certain range for the case OE2o1/3, the original zero out-of-plane vibration of the cable should be changed to the stable in-plane and out-of-plane coupled oscillation by using the optimal passive viscous damper or the MR damper with the SA-1 rule. It is also observed...... to the first in-plane eigenmode of the cable. The numerical results show that the MR damper with the SA-1 rule and the optimal viscous damper perform similarly to mitigate the vibration of the cable under axial periodic support motion, and, in some cases, the SA-2 rule is more favourable in suppressing...... the cable vibration compared with the SA-1 rule. In the final analysis, both the MR damper and the viscous damper can effectively mitigate the out-of-plane component of the cable, while having little effect on the reduction of the in-plane response in most cases. Furthermore, when the support motion...

  12. Two-point active microrheology in a viscous medium exploiting a motional resonance excited in dual-trap optical tweezers

    Science.gov (United States)

    Paul, Shuvojit; Kumar, Randhir; Banerjee, Ayan

    2018-04-01

    Two-point microrheology measurements from widely separated colloidal particles approach the bulk viscosity of the host medium more reliably than corresponding single-point measurements. In addition, active microrheology offers the advantage of enhanced signal to noise over passive techniques. Recently, we reported the observation of a motional resonance induced in a probe particle in dual-trap optical tweezers when the control particle was driven externally [Paul et al., Phys. Rev. E 96, 050102(R) (2017), 10.1103/PhysRevE.96.050102]. We now demonstrate that the amplitude and phase characteristics of the motional resonance can be used as a sensitive tool for active two-point microrheology to measure the viscosity of a viscous fluid. Thus, we measure the viscosity of viscous liquids from both the amplitude and phase response of the resonance, and demonstrate that the zero crossing of the phase response of the probe particle with respect to the external drive is superior compared to the amplitude response in measuring viscosity at large particle separations. We compare our viscosity measurements with those using a commercial rheometer and obtain an agreement ˜1 % . The method can be extended to viscoelastic material where the frequency dependence of the resonance may provide further accuracy for active microrheological measurements.

  13. Measurement of solar neutrinos flux in Russian-American gallium experiment SAGE for half 22-years cycle of solar activity

    International Nuclear Information System (INIS)

    Abdurashitov, D.N.; Veretenkin, E.P.; Vermul, V.M.

    2002-01-01

    The results of measuring the solar neutrino capture on the metallic gallium in the Russian-American experiment SAGE for the period slightly exceeding the half of the 22-year cycle of solar activity, are presented. The results of new measurements since April 1998 are quoted and the analysis of all the measurements, performed by years, months and two-year periods, beginning since 1990 are also presented. Simple analysis of the SAGE results together with the results of other solar neutrino experiments leads to estimating the value of the flux of the pp-neutrinos, reaching the Earth without change in their around, equal to (4.6 ± 1.2) x 10 10 neutrino/(cm 2 s). The value of the flux of the pp-neutrinos, originating in the Sun thermonuclear reactions, is equal to (7.6 ± 2.0) x 10 10 neutrino/(cm 2 s), which agrees well with the standard solar model (5.95 ± 0.6) x 10 10 neutrino/(cm 2 s) [ru

  14. VEGF-A isoform-specific regulation of calcium ion flux, transcriptional activation and endothelial cell migration.

    Science.gov (United States)

    Fearnley, Gareth W; Bruns, Alexander F; Wheatcroft, Stephen B; Ponnambalam, Sreenivasan

    2015-04-24

    Vascular endothelial growth factor A (VEGF-A) regulates many aspects of vascular physiology such as cell migration, proliferation, tubulogenesis and cell-cell interactions. Numerous isoforms of VEGF-A exist but their physiological significance is unclear. Here we evaluated two different VEGF-A isoforms and discovered differential regulation of cytosolic calcium ion flux, transcription factor localisation and endothelial cell response. Analysis of VEGF-A isoform-specific stimulation of VEGFR2-dependent signal transduction revealed differential capabilities for isoform activation of multiple signal transduction pathways. VEGF-A165 treatment promoted increased phospholipase Cγ1 phosphorylation, which was proportional to the subsequent rise in cytosolic calcium ions, in comparison to cells treated with VEGF-A121. A major consequence of this VEGF-A isoform-specific calcium ion flux in endothelial cells is differential dephosphorylation and subsequent nuclear translocation of the transcription factor NFATc2. Using reverse genetics, we discovered that NFATc2 is functionally required for VEGF-A-stimulated endothelial cell migration but not tubulogenesis. This work presents a new mechanism for understanding how VEGF-A isoforms program complex cellular outputs by converting signal transduction pathways into transcription factor redistribution to the nucleus, as well as defining a novel role for NFATc2 in regulating the endothelial cell response. © 2015. Published by The Company of Biologists Ltd.

  15. VEGF-A isoform-specific regulation of calcium ion flux, transcriptional activation and endothelial cell migration

    Directory of Open Access Journals (Sweden)

    Gareth W. Fearnley

    2015-07-01

    Full Text Available Vascular endothelial growth factor A (VEGF-A regulates many aspects of vascular physiology such as cell migration, proliferation, tubulogenesis and cell-cell interactions. Numerous isoforms of VEGF-A exist but their physiological significance is unclear. Here we evaluated two different VEGF-A isoforms and discovered differential regulation of cytosolic calcium ion flux, transcription factor localisation and endothelial cell response. Analysis of VEGF-A isoform-specific stimulation of VEGFR2-dependent signal transduction revealed differential capabilities for isoform activation of multiple signal transduction pathways. VEGF-A165 treatment promoted increased phospholipase Cγ1 phosphorylation, which was proportional to the subsequent rise in cytosolic calcium ions, in comparison to cells treated with VEGF-A121. A major consequence of this VEGF-A isoform-specific calcium ion flux in endothelial cells is differential dephosphorylation and subsequent nuclear translocation of the transcription factor NFATc2. Using reverse genetics, we discovered that NFATc2 is functionally required for VEGF-A-stimulated endothelial cell migration but not tubulogenesis. This work presents a new mechanism for understanding how VEGF-A isoforms program complex cellular outputs by converting signal transduction pathways into transcription factor redistribution to the nucleus, as well as defining a novel role for NFATc2 in regulating the endothelial cell response.

  16. Thermally activated flux creep in strongly layered high-temperature superconductors

    International Nuclear Information System (INIS)

    Chakravarty, S.; Ivlev, B.I.; Ovchinnikov, Y.N.

    1990-01-01

    Thermal activation energies for single vortices and vortex bundles in the presence of a magnetic field parallel to the layers are calculated. The pinning considered is intrinsic and is due to the strongly layered structure of high-temperature superconductors. The magnetic field and the current dependence of the activation energy are studied in detail. The calculation of the activation energy is used to determine the current-voltage characteristic. It may be possible to observe the effects discussed in this paper in a pure enough sample

  17. Asymmetry of neck motion and activation of the cervical paraspinal muscles during prone neck extension in subjects with unilateral posterior neck pain.

    Science.gov (United States)

    Park, Kyue-Nam; Kwon, Oh-Yun; Kim, Su-Jung; Kim, Si-Hyun

    2017-01-01

    Although unilateral posterior neck pain (UPNP) is more prevalent than central neck pain, little is known about how UPNP affects neck motion and the muscle activation pattern during prone neck extension. To investigate whether deviation in neck motion and asymmetry of activation of the bilateral cervical paraspinal muscles occur during prone neck extension in subjects with UPNP compared to subjects without UPNP. This study recruited 20 subjects with UPNP and 20 age- and sex-matched control subjects without such pain. Neck motion and muscle onset time during prone neck extension were measured using a three-dimensional motion-analysis system and surface electromyography. The deviation during prone neck extension was greater in the UPNP group than in the controls (p cervical extensor muscle activation in the UPNP group was significantly delayed on the painful side during prone neck extension (p cervical extensors, triggering a need for specific evaluation and exercises in the management of patients with UPNP.

  18. Solar activity simulation and forecast with a flux-transport dynamo

    Science.gov (United States)

    Macario-Rojas, Alejandro; Smith, Katharine L.; Roberts, Peter C. E.

    2018-06-01

    We present the assessment of a diffusion-dominated mean field axisymmetric dynamo model in reproducing historical solar activity and forecast for solar cycle 25. Previous studies point to the Sun's polar magnetic field as an important proxy for solar activity prediction. Extended research using this proxy has been impeded by reduced observational data record only available from 1976. However, there is a recognised need for a solar dynamo model with ample verification over various activity scenarios to improve theoretical standards. The present study aims to explore the use of helioseismology data and reconstructed solar polar magnetic field, to foster the development of robust solar activity forecasts. The research is based on observationally inferred differential rotation morphology, as well as observed and reconstructed polar field using artificial neural network methods via the hemispheric sunspot areas record. Results show consistent reproduction of historical solar activity trends with enhanced results by introducing a precursor rise time coefficient. A weak solar cycle 25, with slow rise time and maximum activity -14.4% (±19.5%) with respect to the current cycle 24 is predicted.

  19. Potential indirect effects of aerosol on tropical cyclone intensity: convective fluxes and cold-pool activity

    Science.gov (United States)

    Krall, G. M.; Cottom, W. R.

    2012-01-01

    Observational and model evidence suggest that a 2008 Western Pacific typhoon (NURI) ingested elevated concentrations of aerosol as it neared the Chinese coast. This study uses a regional model with two-moment bin-emulating microphysics to simulate the typhoon as it enters the field of elevated aerosol concentrations. A clean maritime field of cloud condensation nuclei (CCN) was prescribed as marine background CCN concentrations and then based on satellite and global aerosol model output, increased to pollution levels and further enhanced in sensitivity tests. The typhoon was simulated for 96 h beginning 17 August 2008. During the final 60 h CCN concentrations were enhanced as it neared the Philippines and coastal China. The model was initialized with both global reanalysis model data and irregularly spaced dropsonde data from the 2008 T-PARC observational campaign using an objective analysis routine. At 36 h, the internal nudging of the model was switched off and allowed to freely evolve on its own. As the typhoon encountered the elevated CCN in the sensitivity tests, a significant perturbation of windspeed, convective fluxes, and hydrometeor species behavior was simulated. Early during the ingestion of enhanced CCN, precipitation was reduced due to suppressed collision and coalescence, and storm winds increased in strength. Subsequently, owing to reduced fall speeds of the smaller drops, greater amounts of condensate were thrust into supercooled levels where the drops froze releasing greater amounts of latent heat of freezing. Convection thereby intensified which resulted in enhanced rainfall and more vigorous convectively-produced downdrafts. As the convection intensified in the outer rainbands the storm drifted over the developing cold-pools. The enhanced cold-pools blocked the inflow of warm, moist air into the core of the typhoon which led to a weakening of the typhoon with significantly reduced low level wind speeds. The very high amounts of pollution

  20. Evaluation on activation activity of reactor in JRR-2 applied 3 dimensional model to neutron flux calculation

    International Nuclear Information System (INIS)

    Kishimoto, Katsumi; Arigane, Kenji

    2005-03-01

    Revaluation to activation activity of reactor evaluated at the notification of dismantling submitted in 1997 was carried out in JRR-2 where decommissioning was advanced now. In the revaluation, estimation accuracy on neutron streaming at various horizontal experimental tubes was improved by applying 3 dimensional model to neutron transport calculation that had been carried out by 2 dimensional model, and calculating with TORT. As the result, excessive overestimations on horizontal experimental tubes and biological shield that had greatly contributed to total activation activity in evaluation at the notification of dismantling was revised, sum of their activation activities in the revaluation decreased to 1/18 (case after 1 year from the permanent shutdown of reactor) of evaluation at the notification of dismantling, and the structural materials that had large activation activity were changed. By the above, it was shown that introducing 3 dimensional model was effective in evaluation on activation activity of the research reactor that had a lot of various experimental tubes. Total activation activity of reactor by the revaluation depended on control rods, thermal shield plates and horizontal experimental tubes, and the value after 1 year from the permanent shutdown of reactor was 1.9x10 14 Bq. (author)

  1. Results of gas flux records in the seismically active area of Val d'Agri (Southern Italy

    Directory of Open Access Journals (Sweden)

    V. Lapenna

    2005-06-01

    Full Text Available The Val d Agri area is well-known for oil exploration. An old 500 m deep exploration well in the northern part of this area has been used for long-term hydrogeochemical investigations. The well is characterized by a discharge of about 500 L/min of thermal water (27.8°C and a simultaneous methane gas emission of about 200 L/min. Gas analyses gave evidence that the methane come from a multiple deep reservoir. Continuous records of gas emission showed some anomalous variations occurred during the past three years. The gas flux anomalies were in a distinctive coincidence with self-potential anomalies of one station close to the hydrogeochemical station. The present paper describes the interpretation of these anomalies in relation to the geodynamic activity in the area.

  2. Active Power and Flux Control of a Self-Excited Induction Generator for a Variable-Speed Wind Turbine Generation

    Energy Technology Data Exchange (ETDEWEB)

    Na, Woonki; Muljadi, Eduard; Leighty, Bill; Kim, Jonghoon

    2017-05-11

    A Self-Excited Induction Generation (SEIG) for a variable speed wind turbine generation(VS-WG) is normally considered to be a good candidate for implementation in stand-alone applications such as battery charging, hydrogenation, water pumping, water purification, water desalination, and etc. In this study, we have examined a study on active power and flux control strategies for a SEIG for a variable speed wind turbine generation. The control analysis for the proposed system is carried out by using PSCAD software. In the process, we can optimize the control design of the system, thereby enhancing and expediting the control design procedure for this application. With this study, this control design for a SEIG for VS-WG can become the industry standard for analysis and development in terms of SEIG.

  3. Twofold reduction of phosphofructokinase activity in Lactococcus lactis results in strong decreases in growth rate and in glycolytic flux

    DEFF Research Database (Denmark)

    Andersen, Heidi Winterberg; Solem, Christian; Hammer, Karin

    2001-01-01

    reduced. Surprisingly, the mutants still showed homolactic fermentation, which indicated that the limitation was different from standard glucose-limited conditions, One explanation could be that the reduced activity of phosphofructokinase resulted in the accumulation of sugar-phosphates. Indeed, when one...... kinase and lactate dehydrogenase remained closer to the wild-type level. In defined medium supplemented with glucose, the growth rate of the mutants was reduced to 57 to 70% of wild-type levels and the glycolytic flux was reduced to 62 to 76% of wild-type levels. In complex medium growth was even further...... of the mutants was starved for glucose in glucose-limited chemostat, the growth rate could gradually be increased to 195% of the growth fate observed in glucose-saturated batch culture, suggesting that phosphofructokinase does affect the concentration of upstream metabolites. The pools of glucose-6- phosphate...

  4. MAGNETIC NON-POTENTIALITY OF SOLAR ACTIVE REGIONS AND PEAK X-RAY FLUX OF THE ASSOCIATED FLARES

    International Nuclear Information System (INIS)

    Tiwari, Sanjiv Kumar; Venkatakrishnan, P.; Gosain, Sanjay

    2010-01-01

    Predicting the severity of solar eruptive phenomena such as flares and coronal mass ejections remains a great challenge despite concerted efforts to do so over the past several decades. However, the advent of high-quality vector magnetograms obtained from Hinode (SOT/SP) has increased the possibility of meeting this challenge. In particular, the spatially averaged signed shear angle (SASSA) seems to be a unique parameter for quantifying the non-potentiality of active regions. We demonstrate the usefulness of the SASSA for predicting flare severity. For this purpose, we present case studies of the evolution of magnetic non-potentiality using 115 vector magnetograms of four active regions, namely, ARs NOAA 10930, 10960, 10961, and 10963 during 2006 December 8-15, 2007 June 3-10, 2007 June 28-July 5, and 2007 July 10-17, respectively. The NOAA ARs 10930 and 10960 were very active and produced X and M class flares, respectively, along with many smaller X-ray flares. On the other hand, the NOAA ARs 10961 and 10963 were relatively less active and produced only very small (mostly A- and B-class) flares. For this study, we have used a large number of high-resolution vector magnetograms obtained from Hinode (SOT/SP). Our analysis shows that the peak X-ray flux of the most intense solar flare emanating from the active regions depends on the magnitude of the SASSA at the time of the flare. This finding of the existence of a lower limit of the SASSA for a given class of X-ray flares will be very useful for space weather forecasting. We have also studied another non-potentiality parameter called the mean weighted shear angle (MWSA) of the vector magnetograms along with the SASSA. We find that the MWSA does not show such distinction as the SASSA for upper limits of the GOES X-ray flux of solar flares; however, both the quantities show similar trends during the evolution of all active regions studied.

  5. Complexity reduction in the H.264/AVC using highly adaptive fast mode decision based on macroblock motion activity

    Science.gov (United States)

    Abdellah, Skoudarli; Mokhtar, Nibouche; Amina, Serir

    2015-11-01

    The H.264/AVC video coding standard is used in a wide range of applications from video conferencing to high-definition television according to its high compression efficiency. This efficiency is mainly acquired from the newly allowed prediction schemes including variable block modes. However, these schemes require a high complexity to select the optimal mode. Consequently, complexity reduction in the H.264/AVC encoder has recently become a very challenging task in the video compression domain, especially when implementing the encoder in real-time applications. Fast mode decision algorithms play an important role in reducing the overall complexity of the encoder. In this paper, we propose an adaptive fast intermode algorithm based on motion activity, temporal stationarity, and spatial homogeneity. This algorithm predicts the motion activity of the current macroblock from its neighboring blocks and identifies temporal stationary regions and spatially homogeneous regions using adaptive threshold values based on content video features. Extensive experimental work has been done in high profile, and results show that the proposed source-coding algorithm effectively reduces the computational complexity by 53.18% on average compared with the reference software encoder, while maintaining the high-coding efficiency of H.264/AVC by incurring only 0.097 dB in total peak signal-to-noise ratio and 0.228% increment on the total bit rate.

  6. 3D Orthogonal Woven Triboelectric Nanogenerator for Effective Biomechanical Energy Harvesting and as Self-Powered Active Motion Sensors.

    Science.gov (United States)

    Dong, Kai; Deng, Jianan; Zi, Yunlong; Wang, Yi-Cheng; Xu, Cheng; Zou, Haiyang; Ding, Wenbo; Dai, Yejing; Gu, Bohong; Sun, Baozhong; Wang, Zhong Lin

    2017-10-01

    The development of wearable and large-area energy-harvesting textiles has received intensive attention due to their promising applications in next-generation wearable functional electronics. However, the limited power outputs of conventional textiles have largely hindered their development. Here, in combination with the stainless steel/polyester fiber blended yarn, the polydimethylsiloxane-coated energy-harvesting yarn, and nonconductive binding yarn, a high-power-output textile triboelectric nanogenerator (TENG) with 3D orthogonal woven structure is developed for effective biomechanical energy harvesting and active motion signal tracking. Based on the advanced 3D structural design, the maximum peak power density of 3D textile can reach 263.36 mW m -2 under the tapping frequency of 3 Hz, which is several times more than that of conventional 2D textile TENGs. Besides, its collected power is capable of lighting up a warning indicator, sustainably charging a commercial capacitor, and powering a smart watch. The 3D textile TENG can also be used as a self-powered active motion sensor to constantly monitor the movement signals of human body. Furthermore, a smart dancing blanket is designed to simultaneously convert biomechanical energy and perceive body movement. This work provides a new direction for multifunctional self-powered textiles with potential applications in wearable electronics, home security, and personalized healthcare. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. The activL® Artificial Disc: a next-generation motion-preserving implant for chronic lumbar discogenic pain

    Directory of Open Access Journals (Sweden)

    Yue JJ

    2016-05-01

    Full Text Available James J Yue,1 Rolando Garcia Jr,2 Larry E Miller3 1Department of Orthopaedic Surgery, Yale School of Medicine, New Haven, CT, 2Orthopedic Care Center, Miami, FL, 3Miller Scientific Consulting, Inc., Asheville, NC, USA Abstract: Degeneration of the lumbar intervertebral discs is a leading cause of chronic low back pain in adults. Treatment options for patients with chronic lumbar discogenic pain unresponsive to conservative management include total disc replacement (TDR or lumbar fusion. Until recently, only two lumbar TDRs had been approved by the US Food and Drug Administration - the Charité Artificial Disc in 2004 and the ProDisc-L Total Disc Replacement in 2006. In June 2015, a next-generation lumbar TDR received Food and Drug Administration approval - the activL® Artificial Disc (Aesculap Implant Systems. Compared to previous-generation lumbar TDRs, the activL® Artificial Disc incorporates specific design enhancements that result in a more precise anatomical match and allow a range of motion that better mimics the healthy spine. The results of mechanical and clinical studies demonstrate that the activL® Artificial Disc results in improved mechanical and clinical outcomes versus earlier-generation artificial discs and compares favorably to lumbar fusion. The purpose of this report is to describe the activL® Artificial Disc including implant characteristics, intended use, surgical technique, postoperative care, mechanical testing, and clinical experience to date. Keywords: activL® Artificial Disc, artificial disc, degenerative disc disease, discogenic, implant, lumbar, motion preservation, pain

  8. Activity, size, and flux of resuspended particles from Rocky Flats soil

    International Nuclear Information System (INIS)

    Langer, G.

    1982-01-01

    Wind erosion processes that resuspend soil from Rocky Flats (rf) sites known as the pad field and the east field were studied. The soil in these sites contains above background amounts of Pu and Am. The following five major areas of concern were studied: Pu levels in source area soil; total Pu activity and activity-particle size relationship in the wind resuspended dust; culpability of suspected source areas for Pu activity reported by the RF surveillance samplers; Pu activity in the respirable and coarse fraction of wind resuspended dust; Pu activity in resuspended dust from wind tunnel simulations of wind erosion. Results indicate that Pu attached to wind blown dust from the pad field and the east field at rf does not present a health hazard. The Pu carrying dust particles are too large (> 3 μm) to be respirable and most are above the inhalable size (> 10 μm). For the July 1981 to March 1982 period, 90% of the Pu collected by the surveillance samplers east of the pad field originated from this field. For those months 90% of the winds over 14 m/s originated from the two western quadrants. Winds over 14 m/s resuspend most of the dust. From April to June 1982 there were no winds over 14 m/s and Pu originated about equally from the pad and east field. Wind tunnel resuspension of dust varied as the 2.8 to 4.2 power of wind speed for a soil moisture range of 14 to 1% respectively. Above 14% moisture little dust was resuspended. No measurable respirable particles (< 3 μm) were resuspended

  9. Toying with Motion.

    Science.gov (United States)

    Galus, Pamela J.

    2002-01-01

    Presents a variety of activities that support the development of an understanding of Newton's laws of motion. Activities use toy cars, mobile roads, and a seat-of-nails. Includes a scoring rubric. (DDR)

  10. Observation-based modelling of permafrost carbon fluxes with accounting for deep carbon deposits and thermokarst activity

    Science.gov (United States)

    Schneider von Deimling, T.; Grosse, G.; Strauss, J.; Schirrmeister, L.; Morgenstern, A.; Schaphoff, S.; Meinshausen, M.; Boike, J.

    2015-06-01

    High-latitude soils store vast amounts of perennially frozen and therefore inert organic matter. With rising global temperatures and consequent permafrost degradation, a part of this carbon stock will become available for microbial decay and eventual release to the atmosphere. We have developed a simplified, two-dimensional multi-pool model to estimate the strength and timing of future carbon dioxide (CO2) and methane (CH4) fluxes from newly thawed permafrost carbon (i.e. carbon thawed when temperatures rise above pre-industrial levels). We have especially simulated carbon release from deep deposits in Yedoma regions by describing abrupt thaw under newly formed thermokarst lakes. The computational efficiency of our model allowed us to run large, multi-centennial ensembles under various scenarios of future warming to express uncertainty inherent to simulations of the permafrost carbon feedback. Under moderate warming of the representative concentration pathway (RCP) 2.6 scenario, cumulated CO2 fluxes from newly thawed permafrost carbon amount to 20 to 58 petagrams of carbon (Pg-C) (68% range) by the year 2100 and reach 40 to 98 Pg-C in 2300. The much larger permafrost degradation under strong warming (RCP8.5) results in cumulated CO2 release of 42 to 141 Pg-C and 157 to 313 Pg-C (68% ranges) in the years 2100 and 2300, respectively. Our estimates only consider fluxes from newly thawed permafrost, not from soils already part of the seasonally thawed active layer under pre-industrial climate. Our simulated CH4 fluxes contribute a few percent to total permafrost carbon release yet they can cause up to 40% of total permafrost-affected radiative forcing in the 21st century (upper 68% range). We infer largest CH4 emission rates of about 50 Tg-CH4 per year around the middle of the 21st century when simulated thermokarst lake extent is at its maximum and when abrupt thaw under thermokarst lakes is taken into account. CH4 release from newly thawed carbon in wetland

  11. Observation-based modelling of permafrost carbon fluxes with accounting for deep carbon deposits and thermokarst activity

    Directory of Open Access Journals (Sweden)

    T. Schneider von Deimling

    2015-06-01

    Full Text Available High-latitude soils store vast amounts of perennially frozen and therefore inert organic matter. With rising global temperatures and consequent permafrost degradation, a part of this carbon stock will become available for microbial decay and eventual release to the atmosphere. We have developed a simplified, two-dimensional multi-pool model to estimate the strength and timing of future carbon dioxide (CO2 and methane (CH4 fluxes from newly thawed permafrost carbon (i.e. carbon thawed when temperatures rise above pre-industrial levels. We have especially simulated carbon release from deep deposits in Yedoma regions by describing abrupt thaw under newly formed thermokarst lakes. The computational efficiency of our model allowed us to run large, multi-centennial ensembles under various scenarios of future warming to express uncertainty inherent to simulations of the permafrost carbon feedback. Under moderate warming of the representative concentration pathway (RCP 2.6 scenario, cumulated CO2 fluxes from newly thawed permafrost carbon amount to 20 to 58 petagrams of carbon (Pg-C (68% range by the year 2100 and reach 40 to 98 Pg-C in 2300. The much larger permafrost degradation under strong warming (RCP8.5 results in cumulated CO2 release of 42 to 141 Pg-C and 157 to 313 Pg-C (68% ranges in the years 2100 and 2300, respectively. Our estimates only consider fluxes from newly thawed permafrost, not from soils already part of the seasonally thawed active layer under pre-industrial climate. Our simulated CH4 fluxes contribute a few percent to total permafrost carbon release yet they can cause up to 40% of total permafrost-affected radiative forcing in the 21st century (upper 68% range. We infer largest CH4 emission rates of about 50 Tg-CH4 per year around the middle of the 21st century when simulated thermokarst lake extent is at its maximum and when abrupt thaw under thermokarst lakes is taken into account. CH4 release from newly thawed carbon in

  12. Procedures for multielement analysis using high-flux fast-neutron activation

    International Nuclear Information System (INIS)

    Williams, R.E.; Hopke, P.K.; Meyer, R.A.

    1981-06-01

    Improvements have been made in the rabbit system used for multi-element fast-neutron activation analysis at the Lawrence Livermore National Laboratory Rotating Target Neutron Source, RTNS-I. Procedures have been developed for the analysis of 20 to 25 elements in samples with an inorganic matrix and 10 to 15 elements in biological samples, without the need for prohibitively expensive, long irradiations. Results are presented for the analysis of fly ash, orchard leaves, and bovine liver

  13. THE FORMATION OF AN INVERSE S-SHAPED ACTIVE-REGION FILAMENT DRIVEN BY SUNSPOT MOTION AND MAGNETIC RECONNECTION

    Energy Technology Data Exchange (ETDEWEB)

    Yan, X. L.; Xue, Z. K.; Wang, J. C.; Yang, L. H. [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China); Priest, E. R. [Mathematics Institute, University of St Andrews, St Andrews, KY16 9SS (United Kingdom); Guo, Q. L., E-mail: yanxl@ynao.ac.cn [College of Mathematics Physics and Information Engineering, Jiaxing University, Jiaxing 314001 (China)

    2016-11-20

    We present a detailed study of the formation of an inverse S-shaped filament prior to its eruption in active region NOAA 11884 from 2013 October 31 to November 2. In the initial stage, clockwise rotation of a small positive sunspot around the main negative trailing sunspot formed a curved filament. Then the small sunspot cancelled with the negative magnetic flux to create a longer active-region filament with an inverse S-shape. At the cancellation site a brightening was observed in UV and EUV images and bright material was transferred to the filament. Later the filament erupted after cancellation of two opposite polarities below the upper part of the filament. Nonlinear force-free field extrapolation of vector photospheric fields suggests that the filament may have a twisted structure, but this cannot be confirmed from the current observations.

  14. Effect of B+ Flux on the electrical activation of ultra-shallow B+ implants in Ge

    DEFF Research Database (Denmark)

    Yates, B.R.; Darby, B.L.; Petersen, Dirch Hjorth

    2012-01-01

    + implants at 2 keV to a dose of 5.0×1014 cm-2 at beam currents ranging from 0.4 to 6.4 mA has been studied using micro Hall effect measurements after annealing at 400°C for 60 s. It has been shown that the sheet number increases with beam current across the investigated range with electrical activation......The residual implanted dose of ultra-shallow B+ implants in Ge was characterized using elastic recoil detection and was determined to correlate well with simulations with a dose loss of 23% due to ion backscattering for 2 keV implants in Ge. The electrical characterization of ultra-shallow B...... being 76% higher at 6.4 mA as compared to 0.4mA. However, at 6.4 mA, the electrically active fraction remained low at 11.4%. Structural characterization revealed that the implanted region remained crystalline and amorphization is not able to explain the increased activation. The results suggest...

  15. Determination of GMPE functional form for an active region with limited strong motion data: application to the Himalayan region

    Science.gov (United States)

    Bajaj, Ketan; Anbazhagan, P.

    2018-01-01

    Advancement in the seismic networks results in formulation of different functional forms for developing any new ground motion prediction equation (GMPE) for a region. Till date, various guidelines and tools are available for selecting a suitable GMPE for any seismic study area. However, these methods are efficient in quantifying the GMPE but not for determining a proper functional form and capturing the epistemic uncertainty associated with selection of GMPE. In this study, the compatibility of the recent available functional forms for the active region is tested for distance and magnitude scaling. Analysis is carried out by determining the residuals using the recorded and the predicted spectral acceleration values at different periods. Mixed effect regressions are performed on the calculated residuals for determining the intra- and interevent residuals. Additionally, spatial correlation is used in mixed effect regression by changing its likelihood function. Distance scaling and magnitude scaling are respectively examined by studying the trends of intraevent residuals with distance and the trend of the event term with magnitude. Further, these trends are statistically studied for a respective functional form of a ground motion. Additionally, genetic algorithm and Monte Carlo method are used respectively for calculating the hinge point and standard error for magnitude and distance scaling for a newly determined functional form. The whole procedure is applied and tested for the available strong motion data for the Himalayan region. The functional form used for testing are five Himalayan GMPEs, five GMPEs developed under NGA-West 2 project, two from Pan-European, and one from Japan region. It is observed that bilinear functional form with magnitude and distance hinged at 6.5 M w and 300 km respectively is suitable for the Himalayan region. Finally, a new regression coefficient for peak ground acceleration for a suitable functional form that governs the attenuation

  16. Identification of Flap Motion Parameters for Vibration Reduction in Helicopter Rotors with Multiple Active Trailing Edge Flaps

    Directory of Open Access Journals (Sweden)

    Uğbreve;ur Dalli

    2011-01-01

    Full Text Available An active control method utilizing the multiple trailing edge flap configuration for rotorcraft vibration suppression and blade loads control is presented. A comprehensive model for rotor blade with active trailing edge flaps is used to calculate the vibration characteristics, natural frequencies and mode shapes of any complex composite helicopter rotor blade. A computer program is developed to calculate the system response, rotor blade root forces and moments under aerodynamic forcing conditions. Rotor blade system response is calculated using the proposed solution method and the developed program depending on any structural and aerodynamic properties of rotor blades, structural properties of trailing edge flaps and properties of trailing edge flap actuator inputs. Rotor blade loads are determined first on a nominal rotor blade without multiple active trailing edge flaps and then the effects of the active flap motions on the existing rotor blade loads are investigated. Multiple active trailing edge flaps are controlled by using open loop controllers to identify the effects of the actuator signal output properties such as frequency, amplitude and phase on the system response. Effects of using multiple trailing edge flaps on controlling rotor blade vibrations are investigated and some design criteria are determined for the design of trailing edge flap controller that will provide actuator signal outputs to minimize the rotor blade root loads. It is calculated that using the developed active trailing edge rotor blade model, helicopter rotor blade vibrations can be reduced up to 36% of the nominal rotor blade vibrations.

  17. Direct and indirect effects of ammonia, ammonium and nitrate on phosphatase activity and carbon fluxes from decomposing litter in peatland

    International Nuclear Information System (INIS)

    Johnson, David; Moore, Lucy; Green, Samuel; Leith, Ian D.; Sheppard, Lucy J.

    2010-01-01

    Here we investigate the response of soils and litter to 5 years of experimental additions of ammonium (NH 4 ), nitrate (NO 3 ), and ammonia (NH 3 ) to an ombrotrophic peatland. We test the importance of direct (via soil) and indirect (via litter) effects on phosphatase activity and efflux of CO 2 . We also determined how species representing different functional types responded to the nitrogen treatments. Our results demonstrate that additions of NO 3 , NH 4 and NH 3 all stimulated phosphatase activity but the effects were dependent on species of litter and mechanism (direct or indirect). Deposition of NH 3 had no effect on efflux of CO 2 from Calluna vulgaris litter, despite it showing signs of stress in the field, whereas both NO 3 and NH 4 reduced CO 2 fluxes. Our results show that the collective impacts on peatlands of the three principal forms of nitrogen in atmospheric deposition are a result of differential effects and mechanisms on individual components. - We found that nitrogen deposition affects microbial activity associated with litter through both indirect and direct mechanisms, but these effects were dependent on the chemical form of inorganic nitrogen compounds.

  18. Cell interactions in concanavalin A activated cation flux and DNA synthesis of mouse lymphocytes

    DEFF Research Database (Denmark)

    Owens, T; Kaplan, J G

    1980-01-01

    Co-culture at constant cell density of nude mouse spleen cells (by themselves unresponsive to the T-cell mitogen concanavalin A (Con A)), with congenic T-enriched lymphocyte suspensions and Con A caused anomalously high activation of K+ transport (measured by 86Rb uptake) and of incorporation...... cells. Attempts to demonstrate a diffusible factor in the supernatants of stimulated T cells were unsuccessful. The measured interaction is sufficient to explain our previous paradoxical findings that enrichment of T cells as measured by membrane markers did not cause a corresponding enrichment...

  19. Epithermal neutron flux distribution and its impact on (n, γ) activation analysis result

    International Nuclear Information System (INIS)

    Jovanovich, S.; Pukotich, P.; Zejnilovich, R.; Corte, F. de; Moens, L.; Hoste, J.; Simonitis, A.

    1985-01-01

    The differences are discussed between the simplified model, introduced to derive the generally accepted ideal 1/E - law, and the conditions existing in an actual reactor. For absolute and comparator types of (n, γ) activation analysis (NAA), the semiempirical 1/Esup(1+α) form is a better approximation - necessary to introduce, but sufficient for practical purposes. Parameter α, being a measure of the epithermal nonideality, is a characteristics of the reactor site. The impact of this nonideality on NAA result is outlined, together with the method for appropriate correction

  20. Myocardial metabolism, perfusion, wall motion and electrical activity in Duchenne muscular dystrophy

    International Nuclear Information System (INIS)

    Perloff, J.K.; Henze, E.; Schelbert, H.R.

    1982-01-01

    The cardiomyopathy of Duchenne's muscular dystrophy originates in the posterobasal left ventricle and extends chiefly to the contiguous lateral wall. Ultrastructural abnormalities in these regions precede connective tissue replacement. We postulated that a metabolic fault coincided with or antedated the subcellular abnormality. Accordingly, regional left ventricular metabolism, perfusion and wall motion were studied using positron computed tomography and metabolic isotopes supplemented by thallium perfusion scans, equilibrium radionuclide angiography and M-mode and two-dimensional echocardiography. To complete the assessment, electrocardiograms, vectorcardiograms, 24 hour taped electrocardiograms and chest x-rays were analyzed. Positron computed tomography utilizing F-18 2-fluoro 2-deoxyglucose (FDG) provided the first conclusive evidence supporting the hypothesis of a premorphologic regional metabolic fault. Thus, cardiac involvement in duchenne dystrophy emerges as a unique form of heart disease, genetically targeting specific regions of ventricular myocardium for initial metabolic and subcellular changes. Reported ultrastructural abnormalities of the impulse and conduction systems provide, at least in part, a basis for the clinically observed sinus node, intraatrial, internodal, AV nodal and infranodal disorders

  1. SIGNATURES OF RELATIVISTIC HELICAL MOTION IN THE ROTATION MEASURES OF ACTIVE GALACTIC NUCLEUS JETS

    Energy Technology Data Exchange (ETDEWEB)

    Broderick, Avery E [Canadian Institute for Theoretical Astrophysics, 60 St. George Street, Toronto, ON M5S 3H8 (Canada); Loeb, Abraham [Institute for Theory and Computation, Harvard University, Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2009-10-01

    Polarization has proven to be an invaluable tool for probing magnetic fields in relativistic jets. Maps of the intrinsic polarization vectors have provided the best evidence to date for uniform, toroidally dominated magnetic fields within jets. More recently, maps of the rotation measure (RM) in jets have for the first time probed the field geometry of the cool, moderately relativistic surrounding material. In most cases, clear signatures of the toroidal magnetic field are detected, corresponding to gradients in RM profiles transverse to the jet. However, in many objects, these profiles also display marked asymmetries that are difficult to explain in simple helical jet models. Furthermore, in some cases, the RM profiles are strongly frequency and/or time dependent. Here we show that these features may be naturally accounted for by including relativistic helical motion in the jet model. In particular, we are able to reproduce bent RM profiles observed in a variety of jets, frequency-dependent RM profile morphologies, and even the time dependence of the RM profiles of knots in 3C 273. Finally, we predict that some sources may show reversals in their RM profiles at sufficiently high frequencies, depending upon the ratio of the components of jet sheath velocity transverse and parallel to the jet. Thus, multi-frequency RM maps promise a novel way in which to probe the velocity structure of relativistic outflows.

  2. Flare activity, sunspot motions, and the evolution of vector magnetic fields in Hale region 17244

    Science.gov (United States)

    Neidig, Donald F.; Hagyard, Mona J.; Machado, Marcos E.; Smith, Jesse B., Jr.

    1986-01-01

    The magnetic and dynamical circumstances leading to the 1B/M4 flare of November 5, 1980 are studied, and a strong association is found between the buildup of magnetic shear and the onset of flare activity within the active region. The development of shear, as observed directly in vector magnetograms, is consistent in detail with the dynamical history of the active region and identifies the precise location of the optical and hard-X-ray kernels of the flare emission.

  3. Correlation of shoulder range of motion limitations at discharge with limitations in activities and participation one year later in persons with spinal cord injury.

    Science.gov (United States)

    Eriks-Hoogland, Inge E; de Groot, Sonja; Post, Marcel W M; van der Woude, Lucas H V

    2011-02-01

    To study the correlation between limited shoulder range of motion in persons with spinal cord injury at discharge and the performance of activities, wheeling performance, transfers and participation one year later. Multicentre prospective cohort study. A total of 146 newly injured subjects with spinal cord injury. Shoulder range of motion was measured at discharge. One year later, Functional Independence Measure (FIM), transfer ability, wheelchair circuit and Physical Activity Scale for Individuals with Physical Disabilities (PASIPD) were assessed. Corrections were made for possible confounding factors (age, gender, level and completeness of injury, time since injury and shoulder pain). All subjects with limited shoulder range of motion at discharge had a lower FIM motor score and were less likely (total group 5 times, and subjects with tetraplegia 10 times less likely) to be able to perform an independent transfer one year later. Subjects with limited shoulder range of motion in the total group needed more time to complete the wheelchair circuit. No significant associations with the PASIPD were found in either group. Persons with spinal cord injury and limited shoulder range of motion at discharge are more limited in their activities one year later than those without limited shoulder range of motion.

  4. The reverse-mode NCX1 activity inhibitor KB-R7943 promotes prostate cancer cell death by activating the JNK pathway and blocking autophagic flux.

    Science.gov (United States)

    Long, Zhou; Chen, BaiJun; Liu, Qian; Zhao, Jiang; Yang, ZhenXing; Dong, XingYou; Xia, LiuBin; Huang, ShengQuan; Hu, XiaoYan; Song, Bo; Li, LongKun

    2016-07-05

    We explored the effects of KB-R7943, an inhibitor of reverse-mode NCX1 activity, in prostate cancer (PCa). NCX1 was overexpressed in PCa tissues and cell lines, and higher NCX1 levels were associated higher PCa grades. At concentrations greater than 10 μM, KB-R7943 dose-dependently decreased PC3 and LNCaP cell viability. KB-R7943 also increased cell cycle G1/S phase arrest and induced apoptosis in PC3 cells. KB-R7943 increased autophagosome accumulation in PCa cells as indicated by increases in LC3-II levels and eGFP-LC3 puncta. Combined treatment with chloroquine (CQ) and KB-R7943 decreased P62 and increased LC3-II protein levels in PC3 cells, indicating that KB-R7943 blocked autophagic flux. KB-R7943 induced autophagosome accumulation mainly by downregulating the PI3K/AKT/m-TOR pathway and upregulating the JNK pathway. In xenograft experiments, KB-R7943 inhibited tumor growth. Combined treatment with KB-R7943 and an autophagy inhibitor inhibited growth and increased apoptosis. These results indicate that KB-R7943 promotes cell death in PCa by activating the JNK signaling pathway and blocking autophagic flux.

  5. Safe-Taipei a Program Project for Strong Motions, Active Faults, and Earthquakes in the Taipei Metropolitan Area

    Science.gov (United States)

    Wang, Jeen-Hwa

    Strong collision between the Eurasian and Philippine Sea Plates causes high seismicity in the Taiwan region, which is often attacked by large earthquakes. Several cities, including three mega-cities, i.e., Taipei, Taichung, and Kaoshung, have been constructed on western Taiwan, where is lying on thick sediments. These cities, with a high-population density, are usually a regional center of culture, economics, and politics. Historically, larger-sized earthquakes, e.g. the 1935 Hsingchu—Taichung earthquake and the 1999 Chi—Chi earthquake, often caused serious damage on the cities. Hence, urban seismology must be one of the main subjects of Taiwan's seismological community. Since 2005, a program project, sponsored by Academia Sinica, has been launched to investigate seismological problems in the Taipei Metropolitan Area. This program project is performed during the 2005—2007 period. The core research subjects are: (1) the deployment of the Taipei Down-hole Seismic Array; (2) the properties of earthquakes and active faults in the area; (3) the seismogenic-zone structures, including the 3-D velocity and Q structures, of the area; (4) the characteristics of strong-motions and sites affects; and (5) strong-motion prediction. In addition to academic goals, the results obtained from the program project will be useful for seismic hazard mitigation not only for the area but also for others.

  6. CURRENT BUILDUP IN EMERGING SERPENTINE FLUX TUBES

    International Nuclear Information System (INIS)

    Pariat, E.; Masson, S.; Aulanier, G.

    2009-01-01

    The increase of magnetic flux in the solar atmosphere during active-region formation involves the transport of the magnetic field from the solar convection zone through the lowest layers of the solar atmosphere, through which the plasma β changes from >1 to <1 with altitude. The crossing of this magnetic transition zone requires the magnetic field to adopt a serpentine shape also known as the sea-serpent topology. In the frame of the resistive flux-emergence model, the rising of the magnetic flux is believed to be dynamically driven by a succession of magnetic reconnections which are commonly observed in emerging flux regions as Ellerman bombs. Using a data-driven, three-dimensional (3D) magnetohydrodynamic numerical simulation of flux emergence occurring in active region 10191 on 2002 November 16-17, we study the development of 3D electric current sheets. We show that these currents buildup along the 3D serpentine magnetic-field structure as a result of photospheric diverging horizontal line-tied motions that emulate the observed photospheric evolution. We observe that reconnection can not only develop following a pinching evolution of the serpentine field line, as usually assumed in two-dimensional geometry, but can also result from 3D shearing deformation of the magnetic structure. In addition, we report for the first time on the observation in the UV domain with the Transition Region and Coronal Explorer (TRACE) of extremely transient loop-like features, appearing within the emerging flux domain, which link several Ellermam bombs with one another. We argue that these loop transients can be explained as a consequence of the currents that build up along the serpentine magnetic field.

  7. Energy Through Motion: An Activity Intervention for Cancer-Related Fatigue in an Ambulatory Infusion Center
.

    Science.gov (United States)

    Abbott, Linda; Hooke, Mary Catherine

    2017-10-01

    Cancer-related fatigue (CRF) occurs in most people with cancer undergoing chemotherapy. Physical activity (PA) is safe and effective in reducing CRF in people with cancer. 
. This project involved the implementation and evaluation of a three-month PA program to maintain or improve CRF and quality of life.
. Activity trackers and resistance bands were provided to participants. Verbal instruction, printed material, activity videos, and text messages were used in this program. Participants completed a fatigue assessment; self-reported PA measure; and measure of attitudes, beliefs, and knowledge about sustaining regular PA pre- and postimplementation.
. 51 patients enrolled in the study, and 39 completed the program. Participants' fatigue did not worsen significantly during the three months, and self-reported activity levels increased, but not significantly. The activity tracker, text messages, and personal connection with nursing staff were reported to be helpful.

  8. The origin of two X-class flares in active region NOAA 12673. Shear flows and head-on collision of new and preexisting flux

    Science.gov (United States)

    Verma, Meetu

    2018-05-01

    Flare-prolific active region NOAA 12673 produced consecutive X2.2 and X9.3 flares on the 6 September 2017. To scrutinize the morphological, magnetic, and horizontal flow properties associated with these flares, a seven-hour time series was used consisting of continuum images, line-of-sight and vector magnetograms, and 1600 Å UV images. These data were acquired with the Helioseismic and Magnetic Imager (HMI) and the Atmospheric Imaging Assembly (AIA). The white-light flare emission differed for both flares, while the X2.2 flare displayed localized, confined flare kernels, the X9.3 flare exhibited a two-ribbon structure. In contrast, the excess UV emission exhibited a similar structure for both flares, but with larger areal extent for the X9.3 flare. These two flares represented a scenario in which the first confined flare acted as precursor, setting up the stage for the more extended flare. Difference maps for continuum and magnetograms revealed locations of significant changes, that is, penumbral decay and umbral strengthening. The curved magnetic polarity inversion line in the δ-spot was the fulcrum of most changes. Horizontal proper motions were computed using the differential affine velocity estimator for vector magnetograms (DAVE4VM). Persistent flow features included (1) strong shear flows along the polarity inversion line, where the negative, parasitic polarity tried to bypass the majority, positive-polarity part of the δ-spot in the north, (2) a group of positive-polarity spots, which moved around the δ-spot in the south, moving away from the δ-spot with significant horizontal flow speeds, and (3) intense moat flows partially surrounding the penumbra of several sunspots, which became weaker in regions with penumbral decay. The enhanced flare activity has its origin in the head-on collision of newly emerging flux with an already existing regular, α-spot. Umbral cores of emerging bipoles were incorporated in its penumbra, creating a δ-configuration with

  9. Low-Enriched Uranium Fuel Conversion Activities for the High Flux Isotope Reactor, Annual Report for FY 2011

    Energy Technology Data Exchange (ETDEWEB)

    Renfro, David G [ORNL; Cook, David Howard [ORNL; Freels, James D [ORNL; Griffin, Frederick P [ORNL; Ilas, Germina [ORNL; Sease, John D [ORNL; Chandler, David [ORNL

    2012-03-01

    This report describes progress made during FY11 in ORNL activities to support converting the High Flux Isotope Reactor (HFIR) from high-enriched uranium (HEU) fuel to low-enriched uranium (LEU) fuel. Conversion from HEU to LEU will require a change in fuel form from uranium oxide to a uranium-molybdenum (UMo) alloy. With both radial and axial contouring of the fuel foil and an increase in reactor power to 100 MW, calculations indicate that the HFIR can be operated with LEU fuel with no degradation in performance to users from the current levels achieved with HEU fuel. Studies are continuing to demonstrate that the fuel thermal safety margins can be preserved following conversion. Studies are also continuing to update other aspects of the reactor steady state operation and accident response for the effects of fuel conversion. Technical input has been provided to Oregon State University in support of their hydraulic testing program. The HFIR conversion schedule was revised and provided to the GTRI program. In addition to HFIR conversion activities, technical support was provided directly to the Fuel Fabrication Capability program manager.

  10. Low-Enriched Uranium Fuel Conversion Activities for the High Flux Isotope Reactor, Annual Report for FY 2011

    International Nuclear Information System (INIS)

    Renfro, David G.; Cook, David Howard; Freels, James D.; Griffin, Frederick P.; Ilas, Germina; Sease, John D.; Chandler, David

    2012-01-01

    This report describes progress made during FY11 in ORNL activities to support converting the High Flux Isotope Reactor (HFIR) from high-enriched uranium (HEU) fuel to low-enriched uranium (LEU) fuel. Conversion from HEU to LEU will require a change in fuel form from uranium oxide to a uranium-molybdenum (UMo) alloy. With both radial and axial contouring of the fuel foil and an increase in reactor power to 100 MW, calculations indicate that the HFIR can be operated with LEU fuel with no degradation in performance to users from the current levels achieved with HEU fuel. Studies are continuing to demonstrate that the fuel thermal safety margins can be preserved following conversion. Studies are also continuing to update other aspects of the reactor steady state operation and accident response for the effects of fuel conversion. Technical input has been provided to Oregon State University in support of their hydraulic testing program. The HFIR conversion schedule was revised and provided to the GTRI program. In addition to HFIR conversion activities, technical support was provided directly to the Fuel Fabrication Capability program manager.

  11. Flux Pinning in Superconductors

    CERN Document Server

    Matsushita, Teruo

    2007-01-01

    The book covers the flux pinning mechanisms and properties and the electromagnetic phenomena caused by the flux pinning common for metallic, high-Tc and MgB2 superconductors. The condensation energy interaction known for normal precipitates or grain boundaries and the kinetic energy interaction proposed for artificial Nb pins in Nb-Ti, etc., are introduced for the pinning mechanism. Summation theories to derive the critical current density are discussed in detail. Irreversible magnetization and AC loss caused by the flux pinning are also discussed. The loss originally stems from the ohmic dissipation of normal electrons in the normal core driven by the electric field induced by the flux motion. The readers will learn why the resultant loss is of hysteresis type in spite of such mechanism. The influence of the flux pinning on the vortex phase diagram in high Tc superconductors is discussed, and the dependencies of the irreversibility field are also described on other quantities such as anisotropy of supercondu...

  12. Installation of a digital, wireless, strong-motion network for monitoring seismic activity in a western Colorado coal mining region

    Energy Technology Data Exchange (ETDEWEB)

    Peter Swanson; Collin Stewart; Wendell Koontz [NIOSH, Spokane, WA (USA). Spokane Research Laboratory

    2007-01-15

    A seismic monitoring network has recently been installed in the North Fork Valley coal mining region of western Colorado as part of a NIOSH mine safety technology transfer project with two longwall coal mine operators. Data recorded with this network will be used to characterize mining related and natural seismic activity in the vicinity of the mines and examine potential hazards due to ground shaking near critical structures such as impoundment dams, reservoirs, and steep slopes. Ten triaxial strong-motion accelerometers have been installed on the surface to form the core of a network that covers approximately 250 square kilometers (100 sq. miles) of rugged canyon-mesa terrain. Spread-spectrum radio networks are used to telemeter continuous streams of seismic waveform data to a central location where they are converted to IP data streams and ported to the Internet for processing, archiving, and analysis. 4 refs.

  13. Superluminal motion of extragalactic objects

    Energy Technology Data Exchange (ETDEWEB)

    Matveenko, L.I. (AN SSSR, Moscow. Inst. Kosmicheskikh Issledovanij)

    1983-07-01

    Extragalactic objects with active nuclei are reviewed. Experimental data are obtained with the method of superfar radiointerferometry. The main peculiarities of the complex structure of Seyfert galaxies, quasars and lacertae objects are considered: the distribution of radiobrightness, spectra, alteration of the density of radiation flux and the distance between the components of sources. The superluminal velocities of component divergence observed are explained by different reasons: fast motion of components considerable difference of the Hubble component or non-cosmologic nature of the red shift of objects, effect of echoreflection of radiation, gravitation lens, systematic alteration of the optical thickness of the object, synchronouys radiation of electrons in the dipole magnetic field, as well as different kinematic illusions connected with the final time of signal propagation.

  14. Superluminal motion of extragalactic objects

    International Nuclear Information System (INIS)

    Matveenko, L.I.

    1983-01-01

    Extragalactic objects with active nuclei are reviewed. Experimental data are obtained with the method of superfar radiointerferometry. The main peculiarities of the complex strUcture of Seyfert galaxies quasars and lacertae ob ects are considered: the distribution of radiobrightness, spectra, alteration of the density of radiation flux and the distance between the components of sources. The superluminal velocities of component divergence observed are explained by different reasons: fast motion of components considerable difference of the Hubble component or non-cosmologic nature of the red shift of objects, effect of echoreflection of radiation, gravitation lens, systematic alteration of the optical thickness of the object, synchronoUs radiation of electrons in the dipole magnetic field, as well as different kinematic illusions connected with the final time of signal propagation

  15. The activL® Artificial Disc: a next-generation motion-preserving implant for chronic lumbar discogenic pain

    Science.gov (United States)

    Yue, James J; Garcia, Rolando; Miller, Larry E

    2016-01-01

    Degeneration of the lumbar intervertebral discs is a leading cause of chronic low back pain in adults. Treatment options for patients with chronic lumbar discogenic pain unresponsive to conservative management include total disc replacement (TDR) or lumbar fusion. Until recently, only two lumbar TDRs had been approved by the US Food and Drug Administration − the Charité Artificial Disc in 2004 and the ProDisc-L Total Disc Replacement in 2006. In June 2015, a next-generation lumbar TDR received Food and Drug Administration approval − the activL® Artificial Disc (Aesculap Implant Systems). Compared to previous-generation lumbar TDRs, the activL® Artificial Disc incorporates specific design enhancements that result in a more precise anatomical match and allow a range of motion that better mimics the healthy spine. The results of mechanical and clinical studies demonstrate that the activL® Artificial Disc results in improved mechanical and clinical outcomes versus earlier-generation artificial discs and compares favorably to lumbar fusion. The purpose of this report is to describe the activL® Artificial Disc including implant characteristics, intended use, surgical technique, postoperative care, mechanical testing, and clinical experience to date. PMID:27274317

  16. Heat flux microsensor measurements

    Science.gov (United States)

    Terrell, J. P.; Hager, J. M.; Onishi, S.; Diller, T. E.

    1992-01-01

    A thin-film heat flux sensor has been fabricated on a stainless steel substrate. The thermocouple elements of the heat flux sensor were nickel and nichrome, and the temperature resistance sensor was platinum. The completed heat flux microsensor was calibrated at the AEDC radiation facility. The gage output was linear with heat flux with no apparent temperature effect on sensitivity. The gage was used for heat flux measurements at the NASA Langley Vitiated Air Test Facility. Vitiated air was expanded to Mach 3.0 and hydrogen fuel was injected. Measurements were made on the wall of a diverging duct downstream of the injector during all stages of the hydrogen combustion tests. Because the wall and the gage were not actively cooled, the wall temperature reached over 1000 C (1900 F) during the most severe test.

  17. Effect of Activated Flux on the Microstructure, Mechanical Properties, and Residual Stresses of Modified 9Cr-1Mo Steel Weld Joints

    Science.gov (United States)

    Maduraimuthu, V.; Vasudevan, M.; Muthupandi, V.; Bhaduri, A. K.; Jayakumar, T.

    2012-02-01

    A novel variant of tungsten inert gas (TIG) welding called activated-TIG (A-TIG) welding, which uses a thin layer of activated flux coating applied on the joint area prior to welding, is known to enhance the depth of penetration during autogenous TIG welding and overcomes the limitation associated with TIG welding of modified 9Cr-1Mo steels. Therefore, it is necessary to develop a specific activated flux for enhancing the depth of penetration during autogeneous TIG welding of modified 9Cr-1Mo steel. In the current work, activated flux composition is optimized to achieve 6 mm depth of penetration in single-pass TIG welding at minimum heat input possible. Then square butt weld joints are made for 6-mm-thick and 10-mm-thick plates using the optimized flux. The effect of flux on the microstructure, mechanical properties, and residual stresses of the A-TIG weld joint is studied by comparing it with that of the weld joints made by conventional multipass TIG welding process using matching filler wire. Welded microstructure in the A-TIG weld joint is coarser because of the higher peak temperature in A-TIG welding process compared with that of multipass TIG weld joint made by a conventional TIG welding process. Transverse strength properties of the modified 9Cr-1Mo steel weld produced by A-TIG welding exceeded the minimum specified strength values of the base materials. The average toughness values of A-TIG weld joints are lower compared with that of the base metal and multipass weld joints due to the presence of δ-ferrite and inclusions in the weld metal caused by the flux. Compressive residual stresses are observed in the fusion zone of A-TIG weld joint, whereas tensile residual stresses are observed in the multipass TIG weld joint.

  18. Integration of canal and otolith inputs by central vestibular neurons is subadditive for both active and passive self-motion: implication for perception.

    Science.gov (United States)

    Carriot, Jerome; Jamali, Mohsen; Brooks, Jessica X; Cullen, Kathleen E

    2015-02-25

    Traditionally, the neural encoding of vestibular information is studied by applying either passive rotations or translations in isolation. However, natural vestibular stimuli are typically more complex. During everyday life, our self-motion is generally not restricted to one dimension, but rather comprises both rotational and translational motion that will simultaneously stimulate receptors in the semicircular canals and otoliths. In addition, natural self-motion is the result of self-generated and externally generated movements. However, to date, it remains unknown how information about rotational and translational components of self-motion is integrated by vestibular pathways during active and/or passive motion. Accordingly, here, we compared the responses of neurons at the first central stage of vestibular processing to rotation, translation, and combined motion. Recordings were made in alert macaques from neurons in the vestibular nuclei involved in postural control and self-motion perception. In response to passive stimulation, neurons did not combine canal and otolith afferent information linearly. Instead, inputs were subadditively integrated with a weighting that was frequency dependent. Although canal inputs were more heavily weighted at low frequencies, the weighting of otolith input increased with frequency. In response to active stimulation, neuronal modulation was significantly attenuated (∼ 70%) relative to passive stimulation for rotations and translations and even more profoundly attenuated for combined motion due to subadditive input integration. Together, these findings provide insights into neural computations underlying the integration of semicircular canal and otolith inputs required for accurate posture and motor control, as well as perceptual stability, during everyday life. Copyright © 2015 the authors 0270-6474/15/353555-11$15.00/0.

  19. The influence of conformational fluctuations on enzymatic activity: modelling the functional motion of β-secretase

    International Nuclear Information System (INIS)

    Neri, M; Cascella, M; Micheletti, C

    2005-01-01

    Considerable insight into the functional activity of proteins and enzymes can be obtained by studying the low energy conformational distortions that the biopolymer can sustain. We carry out the characterization of these large scale structural changes for a protein of considerable pharmaceutical interest, the human β-secretase. Starting from the crystallographic structure of the protein, we use the recently introduced β-Gaussian model to identify, with negligible computational expenditure, the most significant distortions occurring in thermal equilibrium and the associated timescales. The application of this strategy helps us to gain considerable insight into the putative functional movements and, furthermore, allows us to identify a handful of key regions in the protein which have an important mechanical influence on the enzymatic activity despite being spatially distant from the active site. The results obtained within the Gaussian model are validated through an extensive comparison against an all-atom molecular dynamics simulation

  20. Interactive modeling activities in the classroom—rotational motion and smartphone gyroscopes

    Science.gov (United States)

    Pörn, Ray; Braskén, Mats

    2016-11-01

    The wide-spread availability of smartphones makes them a valuable addition to the measurement equipment in both the physics classroom and the instructional laboratory, encouraging an active interaction between measurements and modeling activities. In this paper we illustrate this interaction by making use of the internal gyroscope of a smartphone to study and measure the rotational dynamics of objects rotating about a fixed axis. The workflow described in this paper has been tested in a classroom setting and found to encourage an exploratory approach to both data collecting and modeling.

  1. Analyzing Science Activities in Force and Motion Concepts: A Design of an Immersion Unit

    Science.gov (United States)

    Ayar, Mehmet C.; Aydeniz, Mehmet; Yalvac, Bugrahan

    2015-01-01

    In this paper, we analyze the science activities offered at 7th grade in the Turkish science and technology curriculum along with addressing the curriculum's original intent. We refer to several science education researchers' ideas, including Chinn & Malhotra's (Science Education, 86:175--218, 2002) theoretical framework and Edelson's (1998)…

  2. Happiness in Motion: Emotions, Well-Being, and Active School Travel

    Science.gov (United States)

    Ramanathan, Subha; O'Brien, Catherine; Faulkner, Guy; Stone, Michelle

    2014-01-01

    Background: A pan-Canadian School Travel Planning intervention promoted active school travel (AST). A novel component was exploring emotion, well-being, and travel mode framed by the concept of "sustainable happiness." Relationships between travel mode and emotions, parent perceptions of their child's travel mode on well-being, and…

  3. Moms in motion: a group-mediated cognitive-behavioral physical activity intervention

    Directory of Open Access Journals (Sweden)

    Brawley Lawrence R

    2006-08-01

    Full Text Available Abstract Background When examining the prevalence of physical inactivity by gender and age, women over the age of 25 are at an increased risk for sedentary behavior. Childbearing and motherhood have been explored as one possible explanation for this increased risk. Post natal exercise studies to date demonstrate promising physical and psychological outcomes, however few physical activity interventions have been theory-driven and tailored to post natal exercise initiates. The purpose of this study was to compare the effects of a group-mediated cognitive behavioral intervention based upon social-cognitive theory and group dynamics (GMCB to a standard care postnatal exercise program (SE. Method A randomized, two-arm intervention design was used. Fifty-seven post natal women were randomized to one of two conditions: (1 a standard exercise treatment (SE and (2 a standard exercise treatment plus group-mediated cognitive behavioral intervention (GMCB. Participants in both conditions participated in a four-week intensive phase where participants received standard exercise training. In addition, GMCB participants received self-regulatory behavioral skills training via six group-mediated counseling sessions. Following the intensive phase, participants engaged in a four-week home-based phase of self-structured exercise. Measures of physical activity, barrier efficacy, and proximal outcome expectations were administered and data were analyzed using ANCOVA procedures. Results and discussion ANCOVA of change scores for frequency, minutes, and volume of physical activity revealed significant treatment effects over the intensive and home-based phases (p's Conclusion While both exercise programs resulted in improvements to exercise participation, the GMCB intervention produced greater improvement in overall physical activity, barrier efficacy and proximal outcome expectations.

  4. Evaluation of Children Playing a New-Generation Motion-Sensitive Active Videogame by Accelerometry and Indirect Calorimetry.

    Science.gov (United States)

    Reading, Stacey A; Prickett, Karel

    2013-06-01

    New-generation active videogames (AVGs) use motion-capture video cameras to connect a player's arm, leg, and body movements through three-dimensional space to on-screen activity. We sought to determine if the whole-body movements required to play the AVG elicited moderate-intensity physical activity (PA) in children. A secondary aim was to examine the utility of using accelerometry to measure the activity intensity of AVG play in this age group. The PA levels of boys (n=26) and girls (n=15) 5-12 years of age were measured by triaxial accelerometry (n=25) or accelerometry and indirect calorimetry (IC) (n=16) while playing the "Kinect Adventures!" videogame for the Xbox Kinect (Microsoft(®), Redmond, WA) gaming system. The experiment simulated a typical 20-minute in-home free-play gaming session. Using 10-second recording epochs, the average (mean±standard deviation) PA intensity over 20 minutes was 4.4±0.9, 3.2±0.7, and 3.3±0.6 metabolic equivalents (METs) when estimated by IC or vertical axis (Crouter et al. intermittent lifestyle equation for vertical axis counts/10 seconds [Cva2RM]) and vector magnitude (Crouter et al. intermittent lifestyle equation for vector magnitude counts/10 seconds [Cvm2RM]) accelerometry. In total, 16.9±3.2 (IC), 10.6±4.5 (Cva2RM), and 11.1±3.9 (Cvm2RM) minutes of game playing time were at a 3 MET intensity or higher. In this study, children played the Xbox Kinect AVG at moderate-intensity PA levels. The study also showed that current accelerometry-based methods underestimated the PA of AVG play compared with IC. With proper guidance and recommendations for use, video motion-capture AVG systems could reduce sedentary screen time and increase total daily moderate PA levels for children. Further study of these AVG systems is warranted.

  5. Effect of restricted motion in high temperature on enzymatic activity of the pancreas

    Science.gov (United States)

    Abdusattarov, A.; Smirnova, G. I.

    1980-01-01

    Effects of 30 day hypodynamia coupled with high temperature (35-36 C) on enzymatic activity of the pancreas of male adult rats were studied. The test animals were divided into four groups. Group one served as controls (freedom of movement and a temperature of 25-26 C, considered optimal). The remaining animals were divided into three additional groups: Group two freedom of movement but high temperature (35-36 C); group three hypodynamia but an optimal temperature; group four hypodynamia and 35-36 C. Considerable change in the enzymatic activity in the pancreas of the four groups is observed in three experimental groups (two, three, and four) as compared to the control (group one). The results indicate that adaption of the organism to the thermal factor and restricted movement is accompanied by a change in the enzymatic spectrum of the pancreas. With the combined effect of these two stresses under conditions of the adaption of the organism especially sharp shifts occur in the enzymatic activity.

  6. The AmeriFlux data activity and data system: an evolving collection of data management techniques, tools, products and services

    Science.gov (United States)

    Boden, T. A.; Krassovski, M.; Yang, B.

    2013-06-01

    The Carbon Dioxide Information Analysis Center (CDIAC) at Oak Ridge National Laboratory (ORNL), USA has provided scientific data management support for the US Department of Energy and international climate change science since 1982. Among the many data archived and available from CDIAC are collections from long-term measurement projects. One current example is the AmeriFlux measurement network. AmeriFlux provides continuous measurements from forests, grasslands, wetlands, and croplands in North, Central, and South America and offers important insight about carbon cycling in terrestrial ecosystems. To successfully manage AmeriFlux data and support climate change research, CDIAC has designed flexible data systems using proven technologies and standards blended with new, evolving technologies and standards. The AmeriFlux data system, comprised primarily of a relational database, a PHP-based data interface and a FTP server, offers a broad suite of AmeriFlux data. The data interface allows users to query the AmeriFlux collection in a variety of ways and then subset, visualize and download the data. From the perspective of data stewardship, on the other hand, this system is designed for CDIAC to easily control database content, automate data movement, track data provenance, manage metadata content, and handle frequent additions and corrections. CDIAC and researchers in the flux community developed data submission guidelines to enhance the AmeriFlux data collection, enable automated data processing, and promote standardization across regional networks. Both continuous flux and meteorological data and irregular biological data collected at AmeriFlux sites are carefully scrutinized by CDIAC using established quality-control algorithms before the data are ingested into the AmeriFlux data system. Other tasks at CDIAC include reformatting and standardizing the diverse and heterogeneous datasets received from individual sites into a uniform and consistent network database

  7. The AmeriFlux data activity and data system: an evolving collection of data management techniques, tools, products and services

    Directory of Open Access Journals (Sweden)

    T. A. Boden

    2013-06-01

    Full Text Available The Carbon Dioxide Information Analysis Center (CDIAC at Oak Ridge National Laboratory (ORNL, USA has provided scientific data management support for the US Department of Energy and international climate change science since 1982. Among the many data archived and available from CDIAC are collections from long-term measurement projects. One current example is the AmeriFlux measurement network. AmeriFlux provides continuous measurements from forests, grasslands, wetlands, and croplands in North, Central, and South America and offers important insight about carbon cycling in terrestrial ecosystems. To successfully manage AmeriFlux data and support climate change research, CDIAC has designed flexible data systems using proven technologies and standards blended with new, evolving technologies and standards. The AmeriFlux data system, comprised primarily of a relational database, a PHP-based data interface and a FTP server, offers a broad suite of AmeriFlux data. The data interface allows users to query the AmeriFlux collection in a variety of ways and then subset, visualize and download the data. From the perspective of data stewardship, on the other hand, this system is designed for CDIAC to easily control database content, automate data movement, track data provenance, manage metadata content, and handle frequent additions and corrections. CDIAC and researchers in the flux community developed data submission guidelines to enhance the AmeriFlux data collection, enable automated data processing, and promote standardization across regional networks. Both continuous flux and meteorological data and irregular biological data collected at AmeriFlux sites are carefully scrutinized by CDIAC using established quality-control algorithms before the data are ingested into the AmeriFlux data system. Other tasks at CDIAC include reformatting and standardizing the diverse and heterogeneous datasets received from individual sites into a uniform and consistent

  8. Motion or activity: their role in intra- and inter-subject variation in fMRI

    DEFF Research Database (Denmark)

    Lund, Torben E; Nørgaard, Minna D; Rostrup, Egill

    2005-01-01

    MRI to pre-surgical planning because of a higher requirement for intra-subject precision. The purpose of this study was to investigate the impact of residual movement artefacts on intra-subject and inter-subject variability in the observed fMRI activation. Ten subjects were examined using three different...... word-generation tasks. Two of the subjects were examined 10 times on 10 different days using the same paradigms. We systematically investigated one approach of correcting for residual movement effects: the inclusion of regressors describing movement-related effects in the design matrix of a General...

  9. Concurrent validity and interrater reliability of a new smartphone application to assess 3D active cervical range of motion in patients with neck pain.

    Science.gov (United States)

    Stenneberg, Martijn S; Busstra, Harm; Eskes, Michel; van Trijffel, Emiel; Cattrysse, Erik; Scholten-Peeters, Gwendolijne G M; de Bie, Rob A

    2018-04-01

    There is a lack of valid, reliable, and feasible instruments for measuring planar active cervical range of motion (aCROM) and associated 3D coupling motions in patients with neck pain. Smartphones have advanced sensors and appear to be suitable for these measurements. To estimate the concurrent validity and interrater reliability of a new iPhone application for assessing planar aCROM and associated 3D coupling motions in patients with neck pain, using an electromagnetic tracking device as a reference test. Cross-sectional study. Two samples of neck pain patients were recruited; 30 patients for the validity study and 26 patients for the reliability study. Validity was estimated using intraclass correlation coefficients (ICCs), and by calculating 95% limits of agreement (LoA). To estimate interrater reliability, ICCs were calculated. Cervical 3D coupling motions were analyzed by calculating the cross-correlation coefficients and ratio between the main motions and coupled motions for both instruments. ICCs for concurrent validity and interrater reliability ranged from 0.90 to 0.99. The width of the 95% LoA ranged from about 5° for right lateral bending to 11° for total rotation. No significant differences were found between both devices for associated coupling motion analysis. The iPhone application appears to be a useful discriminative tool for the measurement of planar aCROM and associated coupling motions in patients with neck pain. It fulfills the need for a valid, reliable, and feasible instrument in clinical practice and research. Therapists and researchers should consider measurement error when interpreting scores. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Accretion disc dynamo activity in local simulations spanning weak-to-strong net vertical magnetic flux regimes

    Science.gov (United States)

    Salvesen, Greg; Simon, Jacob B.; Armitage, Philip J.; Begelman, Mitchell C.

    2016-03-01

    Strongly magnetized accretion discs around black holes have attractive features that may explain enigmatic aspects of X-ray binary behaviour. The structure and evolution of these discs are governed by a dynamo-like mechanism, which channels part of the accretion power liberated by the magnetorotational instability (MRI) into an ordered toroidal magnetic field. To study dynamo activity, we performed three-dimensional, stratified, isothermal, ideal magnetohydrodynamic shearing box simulations. The strength of the self-sustained toroidal magnetic field depends on the net vertical magnetic flux, which we vary across almost the entire range over which the MRI is linearly unstable. We quantify disc structure and dynamo properties as a function of the initial ratio of mid-plane gas pressure to vertical magnetic field pressure, β _0^mid = p_gas / p_B. For 10^5 ≥ β _0^mid ≥ 10 the effective α-viscosity parameter scales as a power law. Dynamo activity persists up to and including β _0^mid = 10^2, at which point the entire vertical column of the disc is magnetic pressure dominated. Still stronger fields result in a highly inhomogeneous disc structure, with large density fluctuations. We show that the turbulent steady state βmid in our simulations is well matched by the analytic model of Begelman et al. describing the creation and buoyant escape of toroidal field, while the vertical structure of the disc can be broadly reproduced using this model. Finally, we discuss the implications of our results for observed properties of X-ray binaries.

  11. Happiness in motion: emotions, well-being, and active school travel.

    Science.gov (United States)

    Ramanathan, Subha; O'Brien, Catherine; Faulkner, Guy; Stone, Michelle

    2014-08-01

    A pan-Canadian School Travel Planning intervention promoted active school travel (AST). A novel component was exploring emotion, well-being, and travel mode framed by the concept of "sustainable happiness." Relationships between travel mode and emotions, parent perceptions of their child's travel mode on well-being, and factors related to parent perceptions were examined. Questionnaires were administered to families (N = 5423) from 76 elementary schools. Explanatory variables were demographics (age and sex), school travel measures (mode, distance, accompaniment by an adult, safety, and barriers), and emotions (parent and child). Outcomes examined parent perceived benefits of travel mode on dimensions of well-being (physical, emotional, community, and environmental). Descriptive statistics, chi-square tests and hierarchical regression were used. Parents and children who used AST reported more positive emotions versus passive travelers. Parents of active travelers reported stronger connections to dimensions of well-being. AST had the strongest association with parents' perceptions of their child's well-being, and positive emotions (parent and child) were also significantly related to well-being on the trip to school. As an additional potential benefit of AST, interventions should raise awareness of the positive emotional experiences for children and their parents. Future research should experimentally examine if AST causes these emotional benefits. © 2014, American School Health Association.

  12. Reliability of Using Motion Sensors to Measure Children’s Physical Activity Levels in Exergaming

    Directory of Open Access Journals (Sweden)

    Nan Zeng

    2018-05-01

    Full Text Available Objectives: This study examined the reliability of two objective measurement tools in assessing children’s physical activity (PA levels in an exergaming setting. Methods: A total of 377 children (190 girls, Mage = 8.39, SD = 1.55 attended the 30-min exergaming class every other day for 18 weeks. Children’s PA levels were concurrently measured by NL-1000 pedometer and ActiGraph GT3X accelerometer, while children’s steps per min and time engaged in sedentary, light, and moderate-to-vigorous PA were estimated, respectively. Results: The results of intraclass correlation coefficient (ICC indicated a low degree of reliability (single measures ICC = 0.03 in accelerometers. ANOVA did detect a possible learning effect for 27 classes (p < 0.01, and the single measures ICC was 0.20 for pedometers. Moreover, there was no significant positive relationship between steps per min and time spent in moderate-to-vigorous physical activity (MVPA. Finally, only 1.3% variance was explained by pedometer as a predictor using Hierarchical Linear Modeling to further explore the relationship between pedometer and accelerometer data. Conclusions: The NL-1000 pedometers and ActiGraph GT3X accelerometers have low reliability in assessing elementary school children’s PA levels during exergaming. More research is warranted in determining the reliable and accurate measurement information regarding the use of modern devices in exergaming setting.

  13. Nonlinear mathematical modeling of vibrating motion of nanomechanical cantilever active probe

    Directory of Open Access Journals (Sweden)

    Reza Ghaderi

    Full Text Available Nonlinear vibration response of nanomechanical cantilever (NMC active probes in atomic force microscope (AFM application has been studied in the amplitude mode. Piezoelectric layer is placed piecewise and as an actuator on NMC. Continuous beam model has been chosen for analysis with regard to the geometric discontinuities of piezoelectric layer attachment and NMC's cross section. The force between the tip and the sample surface is modeled using Leonard-Jones potential. Assuming that cantilever is inclined to the sample surface, the effect of nonlinear force on NMC is considered as a shearing force and the concentrated bending moment is regarded at the end. Nonlinear frequency response of NMC is obtained close to the sample surface using the dynamic modeling. It is then become clear that the distance and angle of NMC, the probe length, and the geometric dimensions of piezoelectric layer can affect frequency response bending of the curve.

  14. Assessment of energetic costs of AhR activation by β-naphthoflavone in rainbow trout (Oncorhynchus mykiss) hepatocytes using metabolic flux analysis

    International Nuclear Information System (INIS)

    Nault, Rance; Abdul-Fattah, Hiba; Mironov, Gleb G.; Berezovski, Maxim V.; Moon, Thomas W.

    2013-01-01

    Exposure to environmental contaminants such as activators of the aryl hydrocarbon receptor (AhR) leads to the induction of defense and detoxification mechanisms. While these mechanisms allow organisms to metabolize and excrete at least some of these environmental contaminants, it has been proposed that these mechanisms lead to significant energetic challenges. This study tests the hypothesis that activation of the AhR by the model agonist β-naphthoflavone (βNF) results in increased energetic costs in rainbow trout (Oncorhynchus mykiss) hepatocytes. To address this hypothesis, we employed traditional biochemical approaches to examine energy allocation and metabolism including the adenylate energy charge (AEC), protein synthesis rates, Na + /K + -ATPase activity, and enzyme activities. Moreover, we have used for the first time in a fish cell preparation, metabolic flux analysis (MFA) an in silico approach for the estimation of intracellular metabolic fluxes. Exposure of trout hepatocytes to 1 μM βNF for 48 h did not alter hepatocyte AEC, protein synthesis, or Na + /K + -ATPase activity but did lead to sparing of glycogen reserves and changes in activities of alanine aminotransferase and citrate synthase suggesting altered metabolism. Conversely, MFA did not identify altered metabolic fluxes, although we do show that the dynamic metabolism of isolated trout hepatocytes poses a significant challenge for this type of approach which should be considered in future studies. - Highlights: • Energetic costs of AhR activation by βNF was examined in rainbow trout hepatocytes. • Metabolic flux analysis was performed on a fish cell preparation for the first time. • Exposure to βNF led to sparing of glycogen reserves and altered enzyme activities. • Adenylate energy charge was maintained despite temporal changes in metabolism

  15. Assessment of energetic costs of AhR activation by β-naphthoflavone in rainbow trout (Oncorhynchus mykiss) hepatocytes using metabolic flux analysis

    Energy Technology Data Exchange (ETDEWEB)

    Nault, Rance, E-mail: naultran@msu.edu [Ottawa-Carleton Institute of Biology, Department of Biology and Centre for Advanced Research in Environmental Genomics, University of Ottawa, Ottawa, Ontario, K1N 6N5 (Canada); Abdul-Fattah, Hiba [Ottawa-Carleton Institute of Biology, Department of Biology and Centre for Advanced Research in Environmental Genomics, University of Ottawa, Ottawa, Ontario, K1N 6N5 (Canada); Mironov, Gleb G.; Berezovski, Maxim V. [Ottawa-Carleton Institute of Biology, Department of Biology and Centre for Advanced Research in Environmental Genomics, University of Ottawa, Ottawa, Ontario, K1N 6N5 (Canada); Department of Chemistry, University of Ottawa, Ottawa, Ontario, K1N 6N5 (Canada); Moon, Thomas W. [Ottawa-Carleton Institute of Biology, Department of Biology and Centre for Advanced Research in Environmental Genomics, University of Ottawa, Ottawa, Ontario, K1N 6N5 (Canada)

    2013-08-15

    Exposure to environmental contaminants such as activators of the aryl hydrocarbon receptor (AhR) leads to the induction of defense and detoxification mechanisms. While these mechanisms allow organisms to metabolize and excrete at least some of these environmental contaminants, it has been proposed that these mechanisms lead to significant energetic challenges. This study tests the hypothesis that activation of the AhR by the model agonist β-naphthoflavone (βNF) results in increased energetic costs in rainbow trout (Oncorhynchus mykiss) hepatocytes. To address this hypothesis, we employed traditional biochemical approaches to examine energy allocation and metabolism including the adenylate energy charge (AEC), protein synthesis rates, Na{sup +}/K{sup +}-ATPase activity, and enzyme activities. Moreover, we have used for the first time in a fish cell preparation, metabolic flux analysis (MFA) an in silico approach for the estimation of intracellular metabolic fluxes. Exposure of trout hepatocytes to 1 μM βNF for 48 h did not alter hepatocyte AEC, protein synthesis, or Na{sup +}/K{sup +}-ATPase activity but did lead to sparing of glycogen reserves and changes in activities of alanine aminotransferase and citrate synthase suggesting altered metabolism. Conversely, MFA did not identify altered metabolic fluxes, although we do show that the dynamic metabolism of isolated trout hepatocytes poses a significant challenge for this type of approach which should be considered in future studies. - Highlights: • Energetic costs of AhR activation by βNF was examined in rainbow trout hepatocytes. • Metabolic flux analysis was performed on a fish cell preparation for the first time. • Exposure to βNF led to sparing of glycogen reserves and altered enzyme activities. • Adenylate energy charge was maintained despite temporal changes in metabolism.

  16. Differences in active range of motion measurements in the upper extremity of patients with writer's cramp compared with healthy controls.

    Science.gov (United States)

    Srivanitchapoom, Prachaya; Shamim, Ejaz A; Diomi, Pierre; Hattori, Takaaki; Pandey, Sanjay; Vorbach, Sherry; Park, Jung E; Wu, Tianxia; Auh, Sungyoung; Hallett, Mark

    Exploratory case-control study. Writer's cramp (WC) is a type of focal hand dystonia. The central nervous system plays a role in its pathophysiology, but abnormalities in the affected musculoskeletal components may also be relevant. We compared the active range of motion (ROM) in patients with WC and healthy volunteers (HVs) and correlated the findings with disease duration and severity. Affected limb joints were measured with goniometers. Patients were assessed at least 3 months after their last botulinum toxin (botulinum neurotoxin) injection, and strength was clinically normal. t tests were used to compare the ROMs of WC with matched HVs. The Spearman correlation coefficient assessed the relationship of active ROMs to the disease duration and handwriting subscore of the Dystonia Disability Scale. ROMs of D1 metacarpophalangeal (MCP) joint extension as well as D2 and D5 MCP flexion were significantly smaller in WC, and distal interphalangeal joint extension in D3 and D5 was significantly greater compared with HVs. There were negative correlations between D2 MCP flexion and disease duration and with Dystonia Disability Scale. Abnormalities in ROMs in WC were found. Severity and disease duration correlated with reduced D2 MCP flexion. This may be related to intrinsic biomechanical abnormalities, co-contraction of muscles, or a combination of subclinical weakness and atrophy from repeated botulinum neurotoxin injections. Hand biomechanical properties should not be ignored in the pathophysiology of WC. 2c. Copyright © 2016 Hanley & Belfus. All rights reserved.

  17. Non-equilibrium thermodynamical description of rhythmic motion patterns of active systems: a canonical-dissipative approach.

    Science.gov (United States)

    Dotov, D G; Kim, S; Frank, T D

    2015-02-01

    We derive explicit expressions for the non-equilibrium thermodynamical variables of a canonical-dissipative limit cycle oscillator describing rhythmic motion patterns of active systems. These variables are statistical entropy, non-equilibrium internal energy, and non-equilibrium free energy. In particular, the expression for the non-equilibrium free energy is derived as a function of a suitable control parameter. The control parameter determines the Hopf bifurcation point of the deterministic active system and describes the effective pumping of the oscillator. In analogy to the equilibrium free energy of the Landau theory, it is shown that the non-equilibrium free energy decays as a function of the control parameter. In doing so, a similarity between certain equilibrium and non-equilibrium phase transitions is pointed out. Data from an experiment on human rhythmic movements is presented. Estimates for pumping intensity as well as the thermodynamical variables are reported. It is shown that in the experiment the non-equilibrium free energy decayed when pumping intensity was increased, which is consistent with the theory. Moreover, pumping intensities close to zero could be observed at relatively slow intended rhythmic movements. In view of the Hopf bifurcation underlying the limit cycle oscillator model, this observation suggests that the intended limit cycle movements were actually more similar to trajectories of a randomly perturbed stable focus. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  18. Dynamic Three-Dimensional Shoulder Mri during Active Motion for Investigation of Rotator Cuff Diseases.

    Directory of Open Access Journals (Sweden)

    Christine Tempelaere

    Full Text Available MRI is the standard methodology in diagnosis of rotator cuff diseases. However, many patients continue to have pain despite treatment, and MRI of a static unloaded shoulder seems insufficient for best diagnosis and treatment. This study evaluated if Dynamic MRI provides novel kinematic data that can be used to improve the understanding, diagnosis and best treatment of rotator cuff diseases.Dynamic MRI provided real-time 3D image series and was used to measure changes in the width of subacromial space, superior-inferior translation and anterior-posterior translation of the humeral head relative to the glenoid during active abduction. These measures were investigated for consistency with the rotator cuff diseases classifications from standard MRI.The study included: 4 shoulders with massive rotator cuff tears, 5 shoulders with an isolated full-thickness supraspinatus tear, 5 shoulders with tendinopathy and 6 normal shoulders. A change in the width of subacromial space greater than 4mm differentiated between rotator cuff diseases with tendon tears (massive cuff tears and supraspinatus tear and without tears (tendinopathy (p = 0.012. The range of the superior-inferior translation was higher in the massive cuff tears group (6.4mm than in normals (3.4mm (p = 0.02. The range of the anterior-posterior translation was higher in the massive cuff tears (9.2 mm and supraspinatus tear (9.3 mm shoulders compared to normals (3.5mm and tendinopathy (4.8mm shoulders (p = 0.05.The Dynamic MRI enabled a novel measure; 'Looseness', i.e. the translation of the humeral head on the glenoid during an abduction cycle. Looseness was better able at differentiating different forms of rotator cuff disease than a simple static measure of relative glenohumeral position.

  19. Global Distribution and Variations of NO Infrared Radiative Flux and Its Responses to Solar Activity and Geomagnetic Activity in the Thermosphere

    Science.gov (United States)

    Tang, Chaoli; Wei, Yuanyuan; Liu, Dong; Luo, Tao; Dai, Congming; Wei, Heli

    2017-12-01

    The global distribution and variations of NO infrared radiative flux (NO-IRF) are presented during 2002-2016 in the thermosphere covering 100-280 km altitude based on Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) data set. For investigating the spatial variations of the mutual relationship between NO-IRF and solar activity, the altitude ranges from 100 km to 280 km are divided into 90 altitude bins, and the latitude regions of 83°S-83°N are divided into 16 latitude bins. By processing about 1.8E9 NO-IRF observation values from about 5E6 vertical nighttime profiles recorded in SABER data set, we obtained more than 4.1E8 samples of NO-IRF. The annual-mean values of NO-IRF are then calculated by all available NO-IRF samples within each latitude and altitude bin. Local latitudinal maxima in NO-IRF are found between 120 and 145 km altitude, and the maximum NO-IRF located at polar regions are 3 times more than that of the minimum at equatorial region. The influences of solar and geomagnetic activity on the spatial variations of NO-IRF are investigated. Both the NO-IRF and its response to solar and geomagnetic activity show nearly symmetric distribution between the two hemispheres. It is demonstrated that the observed changes in NO-IRF at altitudes between 100 and 225 km correlate well with the changes in solar activity. The NO-IRF at solar maximum is about 4 times than that at solar minimum, and the current maximum of NO-IRF in 2014 is less than 70% of the prior maximum in 2001. For the first time, the response ranges of the NO-IRF to solar and geomagnetic activity at different altitudes and latitudes are reported.

  20. Reasons for the lack of benefit of immediate angioplasty during recombinant tissue plasminogen activator therapy for acute myocardial infarction: a regional wall motion analysis. European Cooperative Study Group

    NARCIS (Netherlands)

    Arnold, A. E.; Serruys, P. W.; Rutsch, W.; Simoons, M. L.; de Bono, D. P.; Tijssen, J. G.; Lubsen, J.; Verstraete, M.

    1991-01-01

    Regional ventricular wall motion analysis utilizing three different methods was performed on predischarge left ventriculograms from 291 of 367 patients enrolled in a randomized trial of single chain recombinant tissue-type plasminogen activator (rt-PA), aspirin and heparin with and without immediate

  1. Correlation of shoulder range of motion limitations at discharge with limitations in activities and participation one year later in persons with spinal cord injury

    NARCIS (Netherlands)

    Eriks-Hoogland, Inge E.; de Groot, Sonja; Post, Marcel W. M.; van der Woude, Lucas H. V.

    Objective: To study the correlation between limited shoulder range of motion in persons with spinal cord injury at discharge and the performance of activities, wheeling performance, transfers and participation one year later. Design: Multicentre prospective cohort study. Subjects: A total of 146

  2. The Effect of Motion Analysis Activities in a Video-Based Laboratory in Students' Understanding of Position, Velocity and Frames of Reference

    Science.gov (United States)

    Koleza, Eugenia; Pappas, John

    2008-01-01

    In this article, we present the results of a qualitative research project on the effect of motion analysis activities in a Video-Based Laboratory (VBL) on students' understanding of position, velocity and frames of reference. The participants in our research were 48 pre-service teachers enrolled in Education Departments with no previous strong…

  3. A PC-program for the calculation of neutron flux and element contents using the ki-method of neutron activation analysis

    International Nuclear Information System (INIS)

    Boulyga, E.G.; Boulyga, S.F.

    2000-01-01

    A computer program is described, which calculates the induced activities of isotopes after irradiation in a known neutron field, thermal and epithermal neutron fluxes from the measured induced activities and from nuclear data of 2-4 monitor nuclides as well as the element concentrations in samples irradiated together with the monitors. The program was developed for operation in Windows 3.1 (or higher). The application of the program for neutron activation analysis allows to simplify the experimental procedure and to reduce the time. The program was tested by measuring different types of standard reference materials at the FRJ-2 (Research Centre, Juelich, Germany) and Triga (University Mainz, Germany) reactors. Comparison of neutron flux parameters calculated by this program with those calculated by a VAX program developed at the Research Centre, Juelich was done. The results of testing seem to be satisfactory. (author)

  4. Developmental axon stretch stimulates neuron growth while maintaining normal electrical activity, intracellular calcium flux, and somatic morphology.

    Science.gov (United States)

    Loverde, Joseph R; Pfister, Bryan J

    2015-01-01

    Elongation of nerve fibers intuitively occurs throughout mammalian development, and is synchronized with expansion of the growing body. While most tissue systems enlarge through mitosis and differentiation, elongation of nerve fibers is remarkably unique. The emerging paradigm suggests that axons undergo stretch as contiguous tissues enlarge between the proximal and distal segments of spanning nerve fibers. While stretch is distinct from growth, tension is a known stimulus which regulates the growth of axons. Here, we hypothesized that the axon stretch-growth process may be a natural form of injury, whereby regenerative processes fortify elongating axons in order to prevent disconnection. Harnessing the live imaging capability of our axon stretch-growth bioreactors, we assessed neurons both during and following stretch for biomarkers associated with injury. Utilizing whole-cell patch clamp recording, we found no evidence of changes in spontaneous action potential activity or degradation of elicited action potentials during real-time axon stretch at strains of up to 18% applied over 5 min. Unlike traumatic axonal injury, functional calcium imaging of the soma revealed no shifts in free intracellular calcium during axon stretch. Finally, the cross-sectional areas of nuclei and cytoplasms were normal, with no evidence of chromatolysis following week-long stretch-growth limited to the lower of 25% strain or 3 mm total daily stretch. The neuronal growth cascade coupled to stretch was concluded to be independent of the changes in membrane potential, action potential generation, or calcium flux associated with traumatic injury. While axon stretch-growth is likely to share overlap with regenerative processes, we conclude that developmental stretch is a distinct stimulus from traumatic axon injury.

  5. Developmental Axon Stretch Stimulates Neuron Growth While Maintaining Normal Electrical Activity, Intracellular Calcium Flux, and Somatic Morphology

    Directory of Open Access Journals (Sweden)

    Joseph R Loverde

    2015-08-01

    Full Text Available Elongation of nerve fibers intuitively occurs throughout mammalian development, and is synchronized with expansion of the growing body. While most tissue systems enlarge through mitosis and differentiation, elongation of nerve fibers is remarkably unique. The emerging paradigm suggests that axons undergo stretch as contiguous tissues enlarge between the proximal and distal segments of spanning nerve fibers. While stretch is distinct from growth, tension is a known stimulus which regulates the growth of axons. Here, we hypothesized that the axon stretch-growth process may be a natural form of injury, whereby regenerative processes fortify elongating axons in order to prevent disconnection. Harnessing the live imaging capability of our axon stretch-growth bioreactors, we assessed neurons both during and following stretch for biomarkers associated with injury. Utilizing whole-cell patch clamp recording, we found no evidence of changes in spontaneous action potential activity or degradation of elicited action potentials during real-time axon stretch at strains of up to 18 % applied over 5 minutes. Unlike traumatic axonal injury, functional calcium imaging of the soma revealed no shifts in free intracellular calcium during axon stretch. Finally, the cross-sectional areas of nuclei and cytoplasms were normal, with no evidence of chromatolysis following week-long stretch-growth limited to the lower of 25 % strain or 3 mm total daily stretch. The neuronal growth cascade coupled to stretch was concluded to be independent of the changes in membrane potential, action potential generation, or calcium flux associated with traumatic injury. While axon stretch-growth is likely to share overlap with regenerative processes, we conclude that developmental stretch is a distinct stimulus from traumatic axon injury.

  6. Statistical mechanics of flux lines in high-temperature superconductors

    International Nuclear Information System (INIS)

    Dasgupta, C.

    1992-01-01

    The shortness of the low temperature coherence lengths of high T c materials leads to new mechanisms of pinning of flux lines. Lattice periodic modulations of the order parameters itself acts to pin vortex lines in regions of the unit cell were the order parameter is small. A presentation of flux creep and flux noise at low temperature and magnetic fields in terms of motion of simple metastable defects on flux lines is made, with a calculation of flux lattice melting. 12 refs

  7. Beyond visual, aural and haptic movement perception: hMT+ is activated by electrotactile motion stimulation of the tongue in sighted and in congenitally blind individuals

    DEFF Research Database (Denmark)

    Matteau, Isabelle; Kupers, Ron; Ricciardi, Emiliano

    2010-01-01

    imaging (fMRI), we investigated brain responses in eight congenitally blind and nine sighted volunteers who had been trained to use the tongue display unit (TDU), a sensory substitution device which converts visual information into electrotactile pulses delivered to the tongue, to resolve a tactile motion...... discrimination task. Stimuli consisted of either static dots, dots moving coherently or dots moving in random directions. Both groups learned the task at the same rate and activated the hMT+ complex during tactile motion discrimination, although at different anatomical locations. Furthermore, the congenitally...

  8. Research Note:Effects of human activities on the Yangtze River suspended sediment flux into the estuary in the last century

    Directory of Open Access Journals (Sweden)

    S. L. Yang

    2004-01-01

    Full Text Available The surface erosion area in the Yangtze River basin increased from 364×103 km2 in the 1950s to 707×103 km2 in 2001 due to a great increase in population. Based on the regression relationship between surface erosion area and population, the surface erosion area was predicted to be about 280×103 km2 at the beginning of the 20th century. The sediment yield, which increased by about 30% during the first six decades of the 20th century, was closely related to the surface erosion area in this river basin. The Yangtze annual suspended sediment flux into the estuary was about 395×106 t a-1 at the beginning of the century, and this gradually increased to an average of 509×106 t a-1 in the 1960s. The increase in the suspended sediment flux into the estuary was accelerated in the 1950s and the 1960s due to the rapid increase in population and land use immediately after the Second World War and the Liberation War. After the riverine suspended sediment flux reached its maximum in the 1960s, it decreased to 6 t a-1 in 2003. Construction of dams was found to be the principal cause for this decreasing trend because, during the same period, (a the riverine water discharge did not show a decreasing trend, (b water diversion was not influential and (c sedimentation in lakes and canals of the middle and lower reaches did not increase. The total storage capacity of reservoirs has increased dramatically over the past half century. The amount of sediment trapped in reservoirs has increased to more than half a billion t a-1. As a result, the suspended sediment flux into the estuary dramatically decreased, even though the sediment yield from many areas of the basin increased in recent decades. Human activities gradually increased the suspended sediment flux into the estuary before the 1960s and then rapidly decreased it. The last century was a period when the Yangtze suspended sediment flux into the estuary was dramatically affected by human activities. Keywords

  9. Sediment-water oxygen, ammonium and soluble reactive phosphorus fluxes in a turbid freshwater estuary (Curonian lagoon, Lithuania: evidences of benthic microalgal activity

    Directory of Open Access Journals (Sweden)

    Marco Bartoli

    2012-07-01

    Full Text Available Seasonal measurements of total and diffusive benthic fluxes were performed during the ice-free period in the Curonian Lagoon (Lithuania. This mostly freshwater hypertrophic basin exhibits wide seasonal variations of water temperature (1-22°C and inorganic nitrogen availability and it is subjected to dramatic blooms of diatoms and cyanobacteria (>100 μg chl a l-1. In this shallow lagoon, nutrient exchanges at the sediment-water interface and the regulating factors have been poorly explored. Overall aim of the present work is to demonstrate that the activity of benthic microalgae, generally neglected in turbid systems, can be a relevant regulator of sedimentary processes. To this purpose, light and dark fluxes of oxygen, ammonium and soluble reactive phosphorus were measured seasonally by intact core laboratory incubation and diffusive fluxes were calculated from sediment profiles. We investigated sandy sediments that were collected from the central area lagoon, that is representative of the most of the shallower lagoon area. Oxygen and ammonium fluxes were significantly different under light and dark incubations, suggesting an active role of benthic microalgae at the sediment-water interface. In the light net oxygen production was measured in three out of four samplings, with July as only exception, and ammonium was retained within sediments. In the dark sediment respiration displayed a temperature-dependent pattern while ammonium efflux increased from March to October. Fluxes of reactive phosphorus varied significantly with sampling seasons but were less affected by the incubation condition. Diffusive fluxes peaked in July, where highest concentration gradients at the interface and theoretical efflux of ammonium and reactive phosphorous were calculated. The marked differences between diffusive and total nutrient fluxes are probably due to photosynthetic activity by benthic microalgae, and thus oxygen production, enhancement of aerobic

  10. Effects of body temperature, passive limb motion and level of anesthesia on the activity of the inspiratory muscles.

    Science.gov (United States)

    D'Angelo, E

    1984-04-01

    The relationships between relative tidal activity (moving average EMG) of the diaphragm (AdiT) and of the external intercostal or parasternal muscles (AicT) and between the rate of rise of these activities (Adi and Aic) were assessed during rebreathing in rabbits with various body temperatures (BT: 34-41 degrees C) before and after vagotomy (VGT), at rest and during passive limb motion (PLM), and in vagotomized rabbits with or without thoracic dorsal rhizotomy (TDR) under light (LBA) or deep barbiturate anesthesia (DBA). Both relationships had the form AicT = a AdiTb and Aic = a' Adib'. In intact normothermic animals under LBA mean values for b and b' were 1.47 and 1.37, a and a' being unity by definition. No changes in b or b' occurred even with TDR: this suggests that the relation between the central command to phrenic and to inspiratory intercostal alpha-motoneurones was the same under all conditions. Neither BT nor PLM modified a', but a changed owing to BT and PLM dependence of the relation between central inspiratory drive and off-switch threshold. Both VGT, independently of BT, and DBA decreased a and a' before but not after TDR, when a and a' reached the lowest values (0.12 and 0.22). Hence VGT and DBA, but not BT and PLM, change the relation between the central command to inspiratory intercostal alpha- and gamma-motoneurones, the multiplicative effect of alpha-gamma linkage on AicT and Aic being prevented by TDR.

  11. An investigation of the neutron flux in bone-fluorine phantoms comparing accelerator based in vivo neutron activation analysis and FLUKA simulation data

    International Nuclear Information System (INIS)

    Mostafaei, F.; McNeill, F.E.; Chettle, D.R.; Matysiak, W.; Bhatia, C.; Prestwich, W.V.

    2015-01-01

    We have tested the Monte Carlo code FLUKA for its ability to assist in the development of a better system for the in vivo measurement of fluorine. We used it to create a neutron flux map of the inside of the in vivo neutron activation analysis irradiation cavity at the McMaster Accelerator Laboratory. The cavity is used in a system that has been developed for assessment of fluorine levels in the human hand. This study was undertaken to (i) assess the FLUKA code, (ii) find the optimal hand position inside the cavity and assess the effects on precision of a hand being in a non-optimal position and (iii) to determine the best location for our γ-ray detection system within the accelerator beam hall. Simulation estimates were performed using FLUKA. Experimental measurements of the neutron flux were performed using Mn wires. The activation of the wires was measured inside (1) an empty bottle, (2) a bottle containing water, (3) a bottle covered with cadmium and (4) a dry powder-based fluorine phantom. FLUKA was used to simulate the irradiation cavity, and used to estimate the neutron flux in different positions both inside, and external to, the cavity. The experimental results were found to be consistent with the Monte Carlo simulated neutron flux. Both experiment and simulation showed that there is an optimal position in the cavity, but that the effect on the thermal flux of a hand being in a non-optimal position is less than 20%, which will result in a less than 10% effect on the measurement precision. FLUKA appears to be a code that can be useful for modeling of this type of experimental system

  12. Effectiveness of a School-Based Physical Activity Intervention on Cognitive Performance in Danish Adolescents: LCoMotion-Learning, Cognition and Motion

    DEFF Research Database (Denmark)

    Tarp, Jakob; Domazet, Sidsel Louise; Froberg, Karsten

    2016-01-01

    an executive functions test of inhibition (flanker task) with the primary outcomes being accuracy and reaction time on congruent and incongruent trials. Secondary outcomes included mathematics performance, physical activity levels, body-mass index, waist-circumference and cardiorespiratory fitness. RESULTS....../m2 (95% CI: -0.39-0.05). Contrary to our predictions, a significantly larger change in interference control for reaction time was found in favor of the control group (5.0 milliseconds (95% CI: 0-9). Baseline to mid-intervention changes in physical activity levels did not differ significantly between...

  13. Critical current density, irreversibility line, and flux creep activation energy in silver-sheathed Bi2Sr2Ca2Cu3Ox superconducting tapes

    International Nuclear Information System (INIS)

    Shi, D.; Wang, Z.; Sengupta, S.; Smith, M.; Goodrich, L.F.; Dou, S.X.; Liu, H.K.; Guo, Y.C.

    1992-08-01

    Transport data, magnetic hysteresis and flux creep activation energy experimental results are presented for silver-sheathed high-T c Bi 2 Sr 2 Ca 2 Cu 3 O x superconducting tapes. The 110 K superconducting phase was formed by lead doping in a Bi-Sr-Ca-Cu-0 system. The transport critical current density was measured at 4.0 K to be 0.7 x 10 5 A/cm 2 (the corresponding critical current is 74 A) at zero field and 1.6 x 10 4 A/cm 2 at 12 T for H parallel ab. Excellent grain alignment in the a-b plane was achieved by a short-melting method, which considerably improved the critical current density and irreversibility line. Flux creep activation energy as a function of current is obtained based on the magnetic relaxation measurements

  14. Effects of Fatigue on Frontal Plane Knee Motion, Muscle Activity, and Ground Reaction Forces In Men and Women During Landing

    OpenAIRE

    Smith, Michael P.; Sizer, Phillip S.; James, C. Roger

    2009-01-01

    Women tear their Anterior Cruciate Ligament (ACL) 2-8 times more frequently than men. Frontal plane knee motion can produce a pathological load in the ACL. During a state of fatigue the muscles surrounding the knee joint may lose the ability to protect the joint during sudden deceleration while landing. The purpose of this study was to investigate the effects of fatigue and gender on frontal plane knee motion, EMG amplitudes, and GRF magnitudes during drop- jump landing. Pretest-posttest comp...

  15. Effectiveness of a School-Based Physical Activity Intervention on Cognitive Performance in Danish Adolescents: LCoMotion-Learning, Cognition and Motion - A Cluster Randomized Controlled Trial.

    Directory of Open Access Journals (Sweden)

    Jakob Tarp

    Full Text Available Physical activity is associated not only with health-related parameters, but also with cognitive and academic performance. However, no large scale school-based physical activity interventions have investigated effects on cognitive performance in adolescents. The aim of this study was to describe the effectiveness of a school-based physical activity intervention in enhancing cognitive performance in 12-14 years old adolescents.A 20 week cluster randomized controlled trial was conducted including seven intervention and seven control schools. A total of 632 students (mean (SD age: 12.9 (0.6 years completed the trial with baseline and follow-up data on primary or secondary outcomes (74% of randomized subjects. The intervention targeted physical activity during academic subjects, recess, school transportation and leisure-time. Cognitive performance was assessed using an executive functions test of inhibition (flanker task with the primary outcomes being accuracy and reaction time on congruent and incongruent trials. Secondary outcomes included mathematics performance, physical activity levels, body-mass index, waist-circumference and cardiorespiratory fitness.No significant difference in change, comparing the intervention group to the control group, was observed on the primary outcomes (p's>0.05 or mathematics skills (p>0.05. An intervention effect was found for cardiorespiratory fitness in girls (21 meters (95% CI: 4.4-38.6 and body-mass index in boys (-0.22 kg/m2 (95% CI: -0.39-0.05. Contrary to our predictions, a significantly larger change in interference control for reaction time was found in favor of the control group (5.0 milliseconds (95% CI: 0-9. Baseline to mid-intervention changes in physical activity levels did not differ significantly between groups (all p's>0.05.No evidence was found for effectiveness of a 20-week multi-faceted school-based physical activity intervention for enhancing executive functioning or mathematics skills compared

  16. Effectiveness of a School-Based Physical Activity Intervention on Cognitive Performance in Danish Adolescents: LCoMotion-Learning, Cognition and Motion - A Cluster Randomized Controlled Trial.

    Science.gov (United States)

    Tarp, Jakob; Domazet, Sidsel Louise; Froberg, Karsten; Hillman, Charles H; Andersen, Lars Bo; Bugge, Anna

    2016-01-01

    Physical activity is associated not only with health-related parameters, but also with cognitive and academic performance. However, no large scale school-based physical activity interventions have investigated effects on cognitive performance in adolescents. The aim of this study was to describe the effectiveness of a school-based physical activity intervention in enhancing cognitive performance in 12-14 years old adolescents. A 20 week cluster randomized controlled trial was conducted including seven intervention and seven control schools. A total of 632 students (mean (SD) age: 12.9 (0.6) years) completed the trial with baseline and follow-up data on primary or secondary outcomes (74% of randomized subjects). The intervention targeted physical activity during academic subjects, recess, school transportation and leisure-time. Cognitive performance was assessed using an executive functions test of inhibition (flanker task) with the primary outcomes being accuracy and reaction time on congruent and incongruent trials. Secondary outcomes included mathematics performance, physical activity levels, body-mass index, waist-circumference and cardiorespiratory fitness. No significant difference in change, comparing the intervention group to the control group, was observed on the primary outcomes (p's>0.05) or mathematics skills (p>0.05). An intervention effect was found for cardiorespiratory fitness in girls (21 meters (95% CI: 4.4-38.6) and body-mass index in boys (-0.22 kg/m2 (95% CI: -0.39-0.05). Contrary to our predictions, a significantly larger change in interference control for reaction time was found in favor of the control group (5.0 milliseconds (95% CI: 0-9). Baseline to mid-intervention changes in physical activity levels did not differ significantly between groups (all p's>0.05). No evidence was found for effectiveness of a 20-week multi-faceted school-based physical activity intervention for enhancing executive functioning or mathematics skills compared to a

  17. I-f Starting and Active Flux Based Sensorless Vector Control of Reluctance Synchronous Motors, with Experiments

    DEFF Research Database (Denmark)

    Agarlita, Sorin-Christian; Fatu, M.; Tutelea, L. N.

    2010-01-01

    This paper presents a novel, hybrid, motion sensorless control of an axially laminated anisotropic (ALA) reluctance synchronous machine (RSM). By separately controlling Id and Iq currents with the reference currents Id*, Iq* being held constant, and ramping the reference frequency, the motor starts...

  18. Effects of nano-particles strengthening activating flux on the microstructures and mechanical properties of TIG welded AZ31 magnesium alloy joints

    International Nuclear Information System (INIS)

    Xie, Xiong; Shen, Jun; Cheng, Liang; Li, Yang; Pu, Yayun

    2015-01-01

    Highlights: • Increased nano-particles strengthening activating flux degraded TIGed seams. • The reaction between SiC particles and Mg alloy produced Al 4 C 3 and Mg 2 Si phases. • Al 4 C 3 and SiC particles promoted the nucleation and suppressed the growth of α-Mg. • Refined α-Mg grains, precipitated phase and SiC particles enhanced TIGed joints. - Abstract: In this paper, AZ31 magnesium alloy joints were processed by nano-particles strengthening activating flux tungsten inert gas (NSA-TIG) welding, which was achieved by the mixed TiO 2 and nano-SiC particles coated on the samples before welding tests. The macro/micro structural observation and mechanical properties evaluation of the welding joints were conducted by using optical microscope, scanning electron microscope, energy dispersive X-ray spectroscopy, X-ray diffraction and tension and microhardness tests. The results showed that nano-particles strengthening activating flux effective improved the microstructure, microhardness in fusion zone, ultimate tensile strength of the TIG welding joints. In addition, the chemical reaction between part of SiC particles and AZ31 magnesium alloy produced Al 4 C 3 and Mg 2 Si in the joints. The Al 4 C 3 performed as nucleating agents for α-Mg and the dispersed Mg 2 Si and SiC particles enhanced the mechanical properties of the NSA-TIG welding joints. However, large heat input induced by the increase of the surface coating density of the nano-particles strengthening activating flux, increased the α-Mg grain sizes and weakened the mechanical properties of the welded joints. Therefore, the grain size of α-Mg, distribution of β-Mg 17 Al 12 , Mg 2 Si and SiC particles together influenced the evolution of the mechanical properties of the NSA-TIG welded AZ31 magnesium alloy joints

  19. Variations of daytime and nighttime electron temperature and heat flux in the upper ionosphere, topside ionosphere and lower plasmasphere for low and high solar activity

    Czech Academy of Sciences Publication Activity Database

    Truhlík, Vladimír; Třísková, Ludmila; Bilitza, D.; Podolská, Kateřina

    2009-01-01

    Roč. 71, 17-18 (2009), s. 2055-2063 ISSN 1364-6826 R&D Projects: GA AV ČR IAA300420603 Grant - others: NASA (US) NNH06CD17C Institutional research plan: CEZ:AV0Z30420517 Keywords : Electron temperature * Solar activity variation * Latitudinal and field aligned profiles * Heat flux Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.643, year: 2009

  20. Investigations on structure–property relationships of activated flux TIG weldments of super-duplex/austenitic stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Devendranath Ramkumar, K., E-mail: ramdevendranath@gmail.com; Bajpai, Ankur; Raghuvanshi, Shubham; Singh, Anshuman; Chandrasekhar, Aditya; Arivarasu, M.; Arivazhagan, N.

    2015-06-25

    This research work articulated the effect of SiO{sub 2} flux assisted tungsten inert gas (TIG) welding on the microstructure and mechanical properties of marine grade stainless steel weldments, such as super-duplex stainless steel (UNS S32750) and austenitic stainless steel (AISI 316L). The studies showed that the use of flux decreased the heat input required to obtain complete penetration. Microstructure studies revealed the presence of ferrite at the heat affected zone of AISI 316L and the fusion zone which obviated the hot cracking tendency. Tensile studies corroborated that the joint strength was sufficiently greater than that of the parent metals. Impact toughness slightly impoverished owing to the presence of large platelets of Widmanstätten austenite in the fusion zone. The study also explored the structure–property relationships of the flux assisted weldments using the combined techniques of optical and scanning electron microscopy analysis. Owing to the better metallurgical and mechanical properties, this study recommends the use of SiO{sub 2} flux for joining the dissimilar metals involving austenitic and super-duplex stainless steels.

  1. Investigations on structure–property relationships of activated flux TIG weldments of super-duplex/austenitic stainless steels

    International Nuclear Information System (INIS)

    Devendranath Ramkumar, K.; Bajpai, Ankur; Raghuvanshi, Shubham; Singh, Anshuman; Chandrasekhar, Aditya; Arivarasu, M.; Arivazhagan, N.

    2015-01-01

    This research work articulated the effect of SiO 2 flux assisted tungsten inert gas (TIG) welding on the microstructure and mechanical properties of marine grade stainless steel weldments, such as super-duplex stainless steel (UNS S32750) and austenitic stainless steel (AISI 316L). The studies showed that the use of flux decreased the heat input required to obtain complete penetration. Microstructure studies revealed the presence of ferrite at the heat affected zone of AISI 316L and the fusion zone which obviated the hot cracking tendency. Tensile studies corroborated that the joint strength was sufficiently greater than that of the parent metals. Impact toughness slightly impoverished owing to the presence of large platelets of Widmanstätten austenite in the fusion zone. The study also explored the structure–property relationships of the flux assisted weldments using the combined techniques of optical and scanning electron microscopy analysis. Owing to the better metallurgical and mechanical properties, this study recommends the use of SiO 2 flux for joining the dissimilar metals involving austenitic and super-duplex stainless steels

  2. Comparison of erector spinae and hamstring muscle activities and lumbar motion during standing knee flexion in subjects with and without lumbar extension rotation syndrome.

    Science.gov (United States)

    Kim, Si-hyun; Kwon, Oh-yun; Park, Kyue-nam; Kim, Moon-Hwan

    2013-12-01

    The aim of this study was to compare the activity of the erector spinae (ES) and hamstring muscles and the amount and onset of lumbar motion during standing knee flexion between individuals with and without lumbar extension rotation syndrome. Sixteen subjects with lumbar extension rotation syndrome (10 males, 6 females) and 14 healthy subjects (8 males, 6 females) participated in this study. During the standing knee flexion, surface electromyography (EMG) was used to measure muscle activity, and surface EMG electrodes were attached to both the ES and hamstring (medial and lateral) muscles. A three-dimensional motion analysis system was used to measure kinematic data of the lumbar spine. An independent-t test was conducted for the statistical analysis. The group suffering from lumbar extension rotation syndrome exhibited asymmetric muscle activation of the ES and decreased hamstring activity. Additionally, the group with lumbar extension rotation syndrome showed greater and earlier lumbar extension and rotation during standing knee flexion compared to the control group. These data suggest that asymmetric ES muscle activation and a greater amount of and earlier lumbar motion in the sagittal and transverse plane during standing knee flexion may be an important factor contributing to low back pain. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. The microscopic investigation of structures of moving flux lines by ...

    Indian Academy of Sciences (India)

    Abstract. We have used a variety of microscopic techniques to reveal the structure and motion of flux line arrangements, when the flux lines in low Tc type II superconductors are caused to move by a transport current. Using small-angle neutron scattering by the flux line lattice (FLL), we are able to demonstrate directly the ...

  4. Solar proton fluxes since 1956

    International Nuclear Information System (INIS)

    Reedy, R.C.

    1977-01-01

    The fluxes of protons emitted during solar flares since 1956 were evaluated. The depth-versus-activity profiles of 56 Co in several lunar rocks are consistent with the solar-proton fluxes detected by experiments on several satellites. Only about 20% of the solar-proton-induced activities of 22 Na and 55 Fe in lunar rocks from early Apollo missions were produced by protons emitted from the sun during solar cycle 20 (1965--1975). The depth-versus-activity data for these radionuclides in several lunar rocks were used to determine the fluxes of protons during solar cycle 19 (1954--1964). The average proton fluxes for cycle 19 are about five times those for both the last million years and for cycle 20. These solar-proton flux variations correlate with changes in sunspot activity

  5. MCT1 and MCT4 expression and lactate flux activity increase during white and brown adipogenesis and impact adipocyte metabolism

    DEFF Research Database (Denmark)

    Petersen, Charlotte; Nielsen, Mette D.; Andersen, Elise S.

    2017-01-01

    RNA and protein levels of the lactate-H+ transporter MCT1 and the Na+,HCO3 - cotransporter NBCe1 were upregulated in mouse interscapular brown and inguinal white adipose tissue upon cold induction of thermogenesis and browning. MCT1, MCT4, and NBCe1 were furthermore strongly upregulated at the mRNA and protein...... level upon differentiation of cultured pre-adipocytes. Adipocyte differentiation was accompanied by increased plasma membrane lactate flux capacity, which was reduced by MCT inhibition and by MCT1 knockdown. Finally, in differentiated brown adipocytes, glycolysis (assessed as ECAR), and after...... noradrenergic stimulation also oxidative metabolism (OCR), was decreased by MCT inhibition. We suggest that upregulation of MCT1- and MCT4-mediated lactate flux capacity and NBCe1-mediated HCO3 -/pH homeostasis are important for the physiological function of mature adipocytes....

  6. SMALL-SCALE AND GLOBAL DYNAMOS AND THE AREA AND FLUX DISTRIBUTIONS OF ACTIVE REGIONS, SUNSPOT GROUPS, AND SUNSPOTS: A MULTI-DATABASE STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Muñoz-Jaramillo, Andrés; Windmueller, John C.; Amouzou, Ernest C.; Longcope, Dana W. [Department of Physics, Montana State University, Bozeman, MT 59717 (United States); Senkpeil, Ryan R. [Department of Physics, Purdue University, West Lafayette, IN 47907 (United States); Tlatov, Andrey G. [Kislovodsk Mountain Astronomical Station of the Pulkovo Observatory, Kislovodsk 357700 (Russian Federation); Nagovitsyn, Yury A. [Pulkovo Astronomical Observatory, Russian Academy of Sciences, St. Petersburg 196140 (Russian Federation); Pevtsov, Alexei A. [National Solar Observatory, Sunspot, NM 88349 (United States); Chapman, Gary A.; Cookson, Angela M. [San Fernando Observatory, Department of Physics and Astronomy, California State University Northridge, Northridge, CA 91330 (United States); Yeates, Anthony R. [Department of Mathematical Sciences, Durham University, South Road, Durham DH1 3LE (United Kingdom); Watson, Fraser T. [National Solar Observatory, Tucson, AZ 85719 (United States); Balmaceda, Laura A. [Institute for Astronomical, Terrestrial and Space Sciences (ICATE-CONICET), San Juan (Argentina); DeLuca, Edward E. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Martens, Petrus C. H., E-mail: munoz@solar.physics.montana.edu [Department of Physics and Astronomy, Georgia State University, Atlanta, GA 30303 (United States)

    2015-02-10

    In this work, we take advantage of 11 different sunspot group, sunspot, and active region databases to characterize the area and flux distributions of photospheric magnetic structures. We find that, when taken separately, different databases are better fitted by different distributions (as has been reported previously in the literature). However, we find that all our databases can be reconciled by the simple application of a proportionality constant, and that, in reality, different databases are sampling different parts of a composite distribution. This composite distribution is made up by linear combination of Weibull and log-normal distributions—where a pure Weibull (log-normal) characterizes the distribution of structures with fluxes below (above) 10{sup 21}Mx (10{sup 22}Mx). Additionally, we demonstrate that the Weibull distribution shows the expected linear behavior of a power-law distribution (when extended to smaller fluxes), making our results compatible with the results of Parnell et al. We propose that this is evidence of two separate mechanisms giving rise to visible structures on the photosphere: one directly connected to the global component of the dynamo (and the generation of bipolar active regions), and the other with the small-scale component of the dynamo (and the fragmentation of magnetic structures due to their interaction with turbulent convection)

  7. Emergence of Magnetic Flux Generated in a Solar Convective Dynamo. I. The Formation of Sunspots and Active Regions, and The Origin of Their Asymmetries

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Feng; Rempel, Matthias; Fan, Yuhong, E-mail: chenfeng@ucar.edu [High Altitude Observatory, NCAR, P.O. Box 3000, Boulder, CO, 80307 (United States)

    2017-09-10

    We present a realistic numerical model of sunspot and active region formation based on the emergence of flux bundles generated in a solar convective dynamo. To this end, we use the magnetic and velocity fields in a horizontal layer near the top boundary of the solar convective dynamo simulation to drive realistic radiative-magnetohydrodynamic simulations of the uppermost layers of the convection zone. The main results are as follows. (1) The emerging flux bundles rise with the mean speed of convective upflows and fragment into small-scale magnetic elements that further rise to the photosphere, where bipolar sunspot pairs are formed through the coalescence of the small-scale magnetic elements. (2) Filamentary penumbral structures form when the sunspot is still growing through ongoing flux emergence. In contrast to the classical Evershed effect, the inflow seems to prevail over the outflow in a large part of the penumbra. (3) A well-formed sunspot is a mostly monolithic magnetic structure that is anchored in a persistent deep-seated downdraft lane. The flow field outside the spot shows a giant vortex ring that comprises an inflow below 15 Mm depth and an outflow above 15 Mm depth. (4) The sunspots successfully reproduce the fundamental properties of the observed solar active regions, including the more coherent leading spots with a stronger field strength, and the correct tilts of bipolar sunspot pairs. These asymmetries can be linked to the intrinsic asymmetries in the magnetic and flow fields adapted from the convective dynamo simulation.

  8. Research Note:Effects of human activities on the Yangtze River suspended sediment flux into the estuary in the last century

    Science.gov (United States)

    Yang, S. L.; Shi, Z.; Zhao, H. Y.; Li, P.; Dai, S. B.; Gao, A.

    The surface erosion area in the Yangtze River basin increased from 364×103 km2 in the 1950s to 707×103 km2 in 2001 due to a great increase in population. Based on the regression relationship between surface erosion area and population, the surface erosion area was predicted to be about 280×103 km2 at the beginning of the 20th century. The sediment yield, which increased by about 30% during the first six decades of the 20th century, was closely related to the surface erosion area in this river basin. The Yangtze annual suspended sediment flux into the estuary was about 395×106 t a-1 at the beginning of the century, and this gradually increased to an average of 509×106 t a-1 in the 1960s. The increase in the suspended sediment flux into the estuary was accelerated in the 1950s and the 1960s due to the rapid increase in population and land use immediately after the Second World War and the Liberation War. After the riverine suspended sediment flux reached its maximum in the 1960s, it decreased to cause for this decreasing trend because, during the same period, (a) the riverine water discharge did not show a decreasing trend, (b) water diversion was not influential and (c) sedimentation in lakes and canals of the middle and lower reaches did not increase. The total storage capacity of reservoirs has increased dramatically over the past half century. The amount of sediment trapped in reservoirs has increased to more than half a billion t a-1. As a result, the suspended sediment flux into the estuary dramatically decreased, even though the sediment yield from many areas of the basin increased in recent decades. Human activities gradually increased the suspended sediment flux into the estuary before the 1960s and then rapidly decreased it. The last century was a period when the Yangtze suspended sediment flux into the estuary was dramatically affected by human activities.

  9. Studies of vertical fluxes of horizontal momentum in the lower atmosphere using the MU-radar

    Directory of Open Access Journals (Sweden)

    F. S. Kuo

    2008-11-01

    Full Text Available We study the momentum flux of the atmospheric motions in the height ranges between 6 and 22 km observed using the MU radar at Shigaraki in Japan during a 3 day period in January 1988. The data were divided by double Fourier transformation into data set of waves with downward- phase- velocity and data set of waves with upward-phase-velocity for independent momentum flux calculation. The result showed that both the 72 h averaged upward flux and downward flux of zonal momentum were negative at nearly each height, meaning that the upward flux was dominated by westward propagating waves while the downward flux was dominated by eastward propagating waves. The magnitude of the downward flux was approximately a factor of 1.5 larger than the upward flux for waves in the 2~7 h and 7~24 h period bands, and about equal to the upward flux in the 10–30 min and 30 min–2 h period bands. It is also observed that the vertical flux of zonal momentum tended to be small in each frequency band at the altitudes below the jet maximum (10~12 km, and the flux increased toward more negative values to reach a negative maximum at some altitude well above the jet maximum. Daily averaged flux showed tremendous variation: The 1st 24 h (quiet day was relatively quiet, and the fluxes of the 2nd and 3rd 24 h (active days increased sharply. Moreover, the upward fluxes of zonal momentum below 17 km in the quiet day for each period band (10~30 min, 30 min~2 h, 2~7 h, and 7~24 h were dominantly positive, while the corresponding downward fluxes were dominantly negative, meaning that the zonal momentum below 17 km in each period band under study were dominantly eastward (propagating along the mean wind. In the active days, both the upward fluxes and downward fluxes in each frequency band were dominantly negative throughout the whole altitude range 6.1–18.95 km.

  10. Magma production rate along the Ninetyeast Ridge and its relationship to Indian plate motion and Kerguelen hot spot activity

    Digital Repository Service at National Institute of Oceanography (India)

    Sreejith, K.M.; Krishna, K.S.

    production rate along the Walvis Ridge in the Atlantic Ocean. The present study suggests that variations in the Indian plate motion and frequent ridge jumps have a major role in controlling the magma production, particularly on long-period cycles (~16 Myr...

  11. FINE-SCALE STRUCTURES OF FLUX ROPES TRACKED BY ERUPTING MATERIAL

    Energy Technology Data Exchange (ETDEWEB)

    Li Ting; Zhang Jun, E-mail: liting@nao.cas.cn, E-mail: zjun@nao.cas.cn [Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

    2013-06-20

    We present Solar Dynamics Observatory observations of two flux ropes tracked out by material from a surge and a failed filament eruption on 2012 July 29 and August 4, respectively. For the first event, the interaction between the erupting surge and a loop-shaped filament in the east seems to 'peel off' the filament and add bright mass into the flux rope body. The second event is associated with a C-class flare that occurs several minutes before the filament activation. The two flux ropes are, respectively, composed of 85 {+-} 12 and 102 {+-} 15 fine-scale structures, with an average width of about 1.''6. Our observations show that two extreme ends of the flux rope are rooted in opposite polarity fields and each end is composed of multiple footpoints (FPs) of fine-scale structures. The FPs of the fine-scale structures are located at network magnetic fields, with magnetic fluxes from 5.6 Multiplication-Sign 10{sup 18} Mx to 8.6 Multiplication-Sign 10{sup 19} Mx. Moreover, almost half of the FPs show converging motion of smaller magnetic structures over 10 hr before the appearance of the flux rope. By calculating the magnetic fields of the FPs, we deduce that the two flux ropes occupy at least 4.3 Multiplication-Sign 10{sup 20} Mx and 7.6 Multiplication-Sign 10{sup 20} Mx magnetic fluxes, respectively.

  12. Microtremor Array Measurement Survey and Strong Ground Motion Observation Activities of The MarDiM (SATREPS) Project

    Science.gov (United States)

    Ozgur Citak, Seckin; Karagoz, Ozlem; Chimoto, Kosuke; Ozel, Oguz; Yamanaka, Hiroaki; Aksahin, Bengi; Arslan, Safa; Hatayama, Ken; Ohori, Michihiro; Hori, Muneo

    2015-04-01

    Since 1939, devastating earthquakes with magnitude greater than seven ruptured North Anatolian Fault (NAF) westward, starting from 1939 Erzincan (Ms=7.9) at the eastern Turkey and including the latest 1999 Izmit-Golcuk (Ms=7.4) and the Duzce (Ms=7.2) earthquakes in the eastern Marmara region, Turkey. On the other hand, the west of the Sea of Marmara an Mw7.4 earthquake ruptured the NAF' s Ganos segment in 1912. The only un-ruptured segments of the NAF in the last century are within the Sea of Marmara, and are identified as a "seismic gap" zone that its rupture may cause a devastating earthquake. In order to unravel the seismic risks of the Marmara region a comprehensive multidisciplinary research project The MarDiM project "Earthquake And Tsunami Disaster Mitigation in The Marmara Region and Disaster Education in Turkey", has already been started since 2003. The project is conducted in the framework of "Science and Technology Research Partnership for Sustainable Development (SATREPS)" sponsored by Japan Science and Technology Agency (JST) and Japan International Cooperation Agency (JICA). One of the main research field of the project is "Seismic characterization and damage prediction" which aims to improve the prediction accuracy of the estimation of the damages induced by strong ground motions and tsunamis based on reliable source parameters, detailed deep and shallow velocity structure and building data. As for detailed deep and shallow velocity structure microtremor array measurement surveys were conducted in Zeytinburnu district of Istanbul and Tekirdag province at about 81 sites on October 2013 and September 2014. Also in September 2014, 11 accelerometer units were installed mainly in public buildings in both Zeytinburnu and Tekirdag area and are currently in operation. Each accelerometer unit compose of a Network Sensor (CV-374A2) by Tokyo Sokushin, post processing PC for data storage and power supply unit. The Network Sensor (CV-374A2) consist of three servo

  13. Microtremor Array Measurement Survey and Strong Ground Motion observation activities of The SATREPS, MarDiM project -Part 2-

    Science.gov (United States)

    Citak, Seckin; Karagoz, Ozlem; Chimoto, Kosuke; Ozel, Oguz; Yamanaka, Hiroaki; Arslan, Safa; Aksahin, Bengi; Hatayama, Ken; Ohori, Michihiro; Hori, Muneo

    2016-04-01

    Since 1939, devastating earthquakes with magnitude greater than seven ruptured North Anatolian Fault (NAF) westward, starting from 1939 Erzincan (Ms=7.9) at the eastern Turkey and including the latest 1999 Izmit-Golcuk (Ms=7.4) and the Duzce (Ms=7.2) earthquakes in the eastern Marmara region, Turkey. On the other hand, the west of the Sea of Marmara an Mw7.4 earthquake ruptured the NAF' s Ganos segment in 1912. The only un-ruptured segments of the NAF in the last century are within the Sea of Marmara, and are identified as a "seismic gap" zone that its rupture may cause a devastating earthquake. In order to unravel the seismic risks of the Marmara region a comprehensive multidisciplinary research project The MarDiM project "Earthquake And Tsunami Disaster Mitigation in The Marmara Region and Disaster Education in Turkey", has already been started since 2003. The project is conducted in the framework of "Science and Technology Research Partnership for Sustainable Development (SATREPS)" sponsored by Japan Science and Technology Agency (JST) and Japan International Cooperation Agency (JICA). One of the main research field of the project is "Seismic characterization and damage prediction" which aims to improve the prediction accuracy of the estimation of the damages induced by strong ground motions and tsunamis based on reliable source parameters, detailed deep and shallow velocity structure and building data. As for detailed deep and shallow velocity structure microtremor array measurement surveys were conducted in Zeytinburnu district of Istanbul, Tekirdag, Canakkale and Edirne provinces at about 109 sites on October 2013, September 2014 and 2015. Also in September 2014, 11 accelerometer units were installed mainly in public buildings in both Zeytinburnu and Tekirdag area and are currently in operation. Each accelerometer unit compose of a Network Sensor (CV-374A) by Tokyo Sokushin, post processing PC for data storage and power supply unit. The Network Sensor (CV-374

  14. Microtremor Array Measurement Survey and Strong Ground Motion observation activities of The SATREPS, MarDiM project -Part 3-

    Science.gov (United States)

    Citak, Seckin; Safa Arslan, Mehmet; Karagoz, Ozlem; Chimoto, Kosuke; Ozel, Oguz; Yamanaka, Hiroaki; Behiye Aksahin, Bengi; Hatayama, Ken; Sahin, Abdurrahman; Ohori, Michihiro; Safak, Erdal; Hori, Muneo

    2017-04-01

    Since 1939, devastating earthquakes with magnitude greater than seven ruptured North Anatolian Fault (NAF) westward, starting from 1939 Erzincan (Ms=7.9) at the eastern Turkey and including the latest 1999 Izmit-Golcuk (Ms=7.4) and the Duzce (Ms=7.2) earthquakes in the eastern Marmara region, Turkey. On the other hand, the west of the Sea of Marmara an Mw7.4 earthquake ruptured the NAF' s Ganos segment in 1912. The only un-ruptured segments of the NAF in the last century are within the Sea of Marmara, and are identified as a "seismic gap" zone that its rupture may cause a devastating earthquake. In order to unravel the seismic risks of the Marmara region a comprehensive multidisciplinary research project The MarDiM project "Earthquake And Tsunami Disaster Mitigation in The Marmara Region and Disaster Education in Turkey", has already been started since 2003. The project is conducted in the framework of "Science and Technology Research Partnership for Sustainable Development (SATREPS)" sponsored by Japan Science and Technology Agency (JST) and Japan International Cooperation Agency (JICA). One of the main research field of the project is "Seismic characterization and damage prediction" which aims to improve the prediction accuracy of the estimation of the damages induced by strong ground motions and tsunamis based on reliable source parameters, detailed deep and shallow velocity structure and building data. As for detailed deep and shallow velocity structure microtremor array measurement surveys were conducted in Zeytinburnu district of Istanbul, Tekirdag, Canakkale and Edirne provinces at about 140 sites on October 2013, September 2014, 2015 and 2016. Also in September 2014, 11 accelerometer units were installed mainly in public buildings in both Zeytinburnu and Tekirdag area and are currently in operation. Each accelerometer unit compose of a Network Sensor (CV-374A) by Tokyo Sokushin, post processing PC for data storage and power supply unit. The Network Sensor

  15. Knee joint motion and muscle activation patterns are altered during gait in individuals with moderate hip osteoarthritis compared to asymptomatic cohort.

    Science.gov (United States)

    Rutherford, Derek; Moreside, Janice; Wong, Ivan

    2015-07-01

    Knee replacements are common after hip replacement for end stage osteoarthritis. Whether abnormal knee mechanics exist in moderate hip osteoarthritis remains undetermined and has implications for understanding early osteoarthritis joint mechanics. The purpose of this study was to determine whether three-dimensional (3D) knee motion and muscle activation patterns in individuals with moderate hip osteoarthritis differ from an asymptomatic cohort and whether these features differ between contra- and ipsilateral knees. 3D motions and medial and lateral quadriceps and hamstring surface electromyography were recorded on 20 asymptomatic individuals and 20 individuals with moderate hip osteoarthritis during treadmill walking, using standardized collection and processing procedures. Principal component analysis was used to derive electromyographic amplitude and temporal waveform features. 3D stance-phase range of motion was calculated. A 2-factor repeated analysis of variance determined significant within-group leg and muscle differences. Student's t-tests identified between group differences, with Bonferroni corrections where applicable (α=0.05). Lower sagittal plane motion between early and mid/late stance (5°, P=0.004, effect size: 0.96) and greater mid-stance quadriceps activity was found in the osteoarthritis group (P=0.01). Compared to the ipsilateral knee, a borderline significant increase in mid-stance hamstring activity was found in the contra-lateral knee of the hip osteoarthritis group (P=0.018). Bilateral knee mechanics were altered, suggesting potentially increased loads and knee muscle fatigue. There was no indication that one knee is more susceptible to osteoarthritis than the other, thus clinicians should include bilateral knee analysis when treating patients with hip osteoarthritis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Determination of Mercury in Aqueous Samples by Means of Neutron Activation Analysis with an Account of Flux Disturbances

    Energy Technology Data Exchange (ETDEWEB)

    Brune, D; Jirlow, K

    1967-08-15

    The technique of low temperature neutron irradiation combined with isotopic exchange separation technique has been applied in the determination of mercury in aqueous samples. The kinetics of the isotopic exchange reaction has been studied for various sample volumes. The effect of the flux perturbation caused by aqueous samples has been investigated for samples of various size and geometry in a central position in a well moderated heavy water reactor. The effect has been studied both theoretically and experimentally. The 'Thermos' code has been used in the calculations.

  17. Determination of Mercury in Aqueous Samples by Means of Neutron Activation Analysis with an Account of Flux Disturbances

    International Nuclear Information System (INIS)

    Brune, D.; Jirlow, K.

    1967-08-01

    The technique of low temperature neutron irradiation combined with isotopic exchange separation technique has been applied in the determination of mercury in aqueous samples. The kinetics of the isotopic exchange reaction has been studied for various sample volumes. The effect of the flux perturbation caused by aqueous samples has been investigated for samples of various size and geometry in a central position in a well moderated heavy water reactor. The effect has been studied both theoretically and experimentally. The 'Thermos' code has been used in the calculations

  18. Development of low-activation design method for reduction of radioactive waste (2). Precise neutron flux and activation estimation of nuclear power plants using MATXSLIB-J33T10

    International Nuclear Information System (INIS)

    Uematsu, Mikio; Hayashi, Katsumi; Nemezawa, Shigeki; Ogata, Tomohiro; Nakata, Mikihiro; Kinno, Masaharu; Yamaguchi, Katsuyoshi; Saito, Minoru; Hasegawa, Akira

    2008-01-01

    We have been developing low-activation concrete for biological shielding wall of nuclear power plants, for the purpose of reducing large amount of radioactive waste. Based on measurement of Eu and Co content in various aggregate candidates, limestone and electro-fused alumina were selected as the most feasible aggregate for low activation concrete. Induced activity in shielding wall was calculated for both low activation concrete and ordinary concrete using neutron flux obtained from DORT two-dimensional calculation made for typical ABWR and APWR models. We have prepared new cross section library named 'MATXSLIB-J33T10 that has multi-group structure in thermal energy. The library was processed from evaluated cross section library JENDL 3.3 by using NJOY 99.83. Activation cross section library for ORIGEN-79 code is prepared for each activation calculation case by collapsing JENDL-3.3 originated 183-group constants into 3-group activation cross section using 183-group neutron flux. One-group activation cross section was also prepared in the same manner for ORIGEN2 calculation. The ΣD/C value results for low-activation concrete was sufficiently low comparing to the ordinary concrete. By using the developed low-activation concrete, activation level of biological shielding wall concrete will be effectively decreased. The use of the developed low-activation concrete will contribute to economization of nuclear power plants decommissioning by reducing large amount of radioactive concrete waste. (author)

  19. Elementary school science teachers' reflection for nature of science: Workshop of NOS explicit and reflective on force and motion learning activity

    Science.gov (United States)

    Patho, Khanittha; Yuenyong, Chokchai; Chamrat, Suthida

    2018-01-01

    The nature of science has been part of Thailand's science education curriculum since 2008. However, teachers lack of understanding about the nature of science (NOS) and its teaching, particularly element school science teachers. In 2012, the Science Institute of Thailand MOE, started a project of Elementary Science Teacher Professional Development to enhance their thinking about the Nature of Science. The project aimed to enhance teachers' understanding of NOS, science teaching for explicit and reflective NOS, with the aim of extending their understanding of NOS to other teachers. This project selected 366 educational persons. The group was made up of a teacher and a teacher supervisor from 183 educational areas in 74 provinces all Thailand. The project provided a one week workshop and a year's follow up. The week-long workshop consisted of 11 activities of science teaching for explicit reflection on 8 aspects of NOS. Workshop of NOS explicit and reflective on force and motion learning activity is one of eight activities. This activity provided participants to learn force and motion and NOS from the traditional toy "Bang-Poh". The activity tried to enhance participants to explicit NOS for 5 aspects including empirical basis, subjectivity, creativity, observation and inference, and sociocultural embeddedness. The explicit NOS worksheet provided questions to ask participants to reflect their existing ideas about NOS. The paper examines elementary school science teachers' understanding of NOS from the force and motion learning activity which provided explicit reflection on 5 NOS aspects. An interpretive paradigm was used to analyse the teachers' reflections in a NOS worksheet. The findings indicated that majority of them could reflect about the empirical basis of science and creativity but few reflected on observation and inference, or sociocultural embeddedness. The paper will explain the teachers' NOS thinking and discuss the further enhancing of their understanding

  20. POLAMI: Polarimetric Monitoring of Active Galactic Nuclei at Millimetre Wavelengths - III. Characterization of total flux density and polarization variability of relativistic jets

    Science.gov (United States)

    Agudo, Iván; Thum, Clemens; Ramakrishnan, Venkatessh; Molina, Sol N.; Casadio, Carolina; Gómez, José L.

    2018-01-01

    We report on the first results of the POLAMI (Polarimetric Monitoring of AGNs with Millimetre Wavelengths) programme, a simultaneous 3.5 and 1.3 mm full-Stokes-polarization monitoring of a sample of 36 of the brightest active galactic nuclei in the northern sky with the IRAM 30 m telescope. Through a systematic statistical study of data taken from 2006 October (from 2009 December for the case of the 1.3 mm observations) to 2014 August, we characterize the variability of the total flux density and linear polarization. We find that all sources in the sample are highly variable in total flux density at both 3.5 and 1.3 mm, as well as in spectral index, which (except in particularly prominent flares) is found to be optically thin between these two wavelengths. The total flux-density variability at 1.3 mm is found, in general, to be faster, and to have larger fractional amplitude and flatter power-spectral-density slopes than at 3.5 mm. The polarization degree is on average larger at 1.3 mm than at 3.5 mm, by a factor of 2.6. The variability of linear polarization degree is faster and has higher fractional amplitude than for total flux density, with the typical time-scales during prominent polarization peaks being significantly faster at 1.3 mm than at 3.5 mm. The polarization angle at both 3.5 and 1.3 mm is highly variable. Most of the sources show one or two excursions of >180° on time-scales from a few weeks to about a year during the course of our observations. The 3.5 and 1.3 mm polarization angle evolution follows each other rather well, although the 1.3 mm data show a clear preference to more prominent variability on the short time-scales, i.e. weeks. The data are compatible with multizone models of conical jets involving smaller emission regions for the shortest-wavelength emitting sites. Such smaller emitting regions should also be more efficient in energising particle populations, as implied by the coherent evolution of the spectral index and the total flux

  1. Assessment of shoulder external rotation range-of-motion on throwing athletes: the effects of testing end-range determination (active versus passive).

    Science.gov (United States)

    Ribeiro, A; Pascoal, A

    2015-07-01

    The purpose of this study was to compare the effects of active or passive end-range determination (supine position) for external rotation range of motion (ROM) in overhead throwing athletes and verify if athletes' ROM is similar to non-athletes. Kinematic data from the dominant shoulder of 24 healthy male subjects, divided into two groups (12 athletes and 12 non-athletes) were recorded at end-range external rotation, thoracohumeral and glenohumeral external rotation angles were compared and a 2-way repeated-measures ANOVA was used to calculate the effects of end-range determination (passive versus active) across groups (athlete and non-athlete). A significant main effect (p external end-range angles was observed while the highest end-range determination values were associated with passive motion. No differences were observed between the athletic or non-athletic groups for either thoracohumeral (p = 0.784) or glenohumeral (p = 0.364) motion.

  2. The impact of respiratory motion and active breathing control on the displacement of target area in patients with gastric cancer treated with post-operative radiotherapy

    International Nuclear Information System (INIS)

    Yu Xiaoli; Zhang Zhen; Gu Weilie; Hu Weigang; Zhu Ji; Cai Gang; Li Guichao; He Shaoqin

    2010-01-01

    Objective: To assess the impact of respiratory motion on the displacement of target area and to analyze the discrimination between free breathing and active breathing control (ABC) in patients with gastric cancer treated with post-operative radiotherapy. Methods: From January 2005 to November 2006, 22 patients with post-operatively confirmed gastric cancer were enrolled in this study. All diseases were T 3 / N +, staging II - IV. Patients were CT scanned and treated by radiation with the use of ABC. Image J software was used in image processing, motion measurement and data analysis. Surgical clips were implanted as fiducial marks in the tumor bed and lymphatic drainage area. The motion range of each clip was measured in the resultant-projection image. Motions of the clips in superior-inferior (S-I), right-left (R-L) and anterior-posterior (A-P) directions were determined from fluoroscopy movies obtained in the treatment position. Results: The motion ranges in S-I, R-L and A-P directions were 11.1 mam, 1.9 mm and 2.5 mm (F = 85.15, P = 0. 000) under free breathing, with 2.2 mm, 1.1 mm and 1.7 nun under ABC (F = 17.64, P = 0. 000), and the reduction of motion ranges was significant in both S-I and A-P directions (t = 4.36, P = 0. 000;t = 3.73,P = 0.000). When compared with under free-breathing, the motion ranges under ABC were kept unchanged in the same breathing phase of the same treatment fraction, while significant increased in different breathing phase in all three directions (t = - 4.36, P = 0. 000; t = - 3.52, P = 0.000; t =-3.79, P = 0. 000), with a numerical value of 3.7 mm, 1.6 mm and 2.8 mm, respectively (F = 19.46, P = 0. 000) . With ABC between different treatment fractions , the maximum displacements were 2.7 mm, 1.7 mm and 2.5 mm for the centre of the clip cluster (F =4.07,P =0. 019), and were 4.6 mm, 3.1 mm and 4.2 mm for the clips (F =5.17 ,P =0.007). The motion ranges were significant increased in all the three directions (t = - 4.09, P=0.000 ; t =-4

  3. The Implementation of Problem-Solving Based Laboratory Activities to Teach the Concept of Simple Harmonic Motion in Senior High School

    Science.gov (United States)

    Iradat, R. D.; Alatas, F.

    2017-09-01

    Simple harmonic motion is considered as a relatively complex concept to be understood by students. This study attempts to implement laboratory activities that focus on solving contextual problems related to the concept. A group of senior high school students participated in this pre-experimental method from a group’s pretest-posttest research design. Laboratory activities have had a positive impact on improving students’ scientific skills, such as, formulating goals, conducting experiments, applying laboratory tools, and collecting data. Therefore this study has added to the theoretical and practical knowledge that needs to be considered to teach better complicated concepts in physics learning.

  4. Thermally activated flux flow effects in single crystalline Bi2Sr2CaCu2O8 observed via magnetic measurements

    International Nuclear Information System (INIS)

    Vandenberg, J.; Vanderbeek, C.J.; Koorevaar, P.; Kes, P.H.; Mydosh, J.A.; Menken, M.J.V.; Menovsky, A.A.

    1989-01-01

    In this paper the authors present time-dependent magnetization and high-temperature, low-field critical-current measurements on single crystalline Bi 2 Sr 2 CaCu 2 O 8 . A short introduction to thermally activated flux-flow theory (TAFF) is given based on solving a continuity equation for fluxlines with several boundary conditions. A comparison between this theory and experiments indicates the self consistency of the TAFF model, by relating the temperature dependences of J c and of the typical relaxation time τ 0 of M(t). Furthermore, values for the pinning potential U are obtained at several temperatures

  5. On the Ability of Space-Based Passive and Active Remote Sensing Observations of CO2 to Detect Flux Perturbations to the Carbon Cycle

    Science.gov (United States)

    Crowell, Sean M. R.; Randolph Kawa, S.; Browell, Edward V.; Hammerling, Dorit M.; Moore, Berrien; Schaefer, Kevin; Doney, Scott C.

    2018-01-01

    Space-borne observations of CO2 are vital to gaining understanding of the carbon cycle in regions of the world that are difficult to measure directly, such as the tropical terrestrial biosphere, the high northern and southern latitudes, and in developing nations such as China. Measurements from passive instruments such as GOSAT and OCO-2, however, are constrained by solar zenith angle limitations as well as sensitivity to the presence of clouds and aerosols. Active measurements such as those in development for the Active Sensing of CO2 Emissions over Nights, Days and Seasons (ASCENDS) mission show strong potential for making measurements in the high-latitude winter and in cloudy regions. In this work we examine the enhanced flux constraint provided by the improved coverage from an active measurement such as ASCENDS. The simulation studies presented here show that with sufficient precision, ASCENDS will detect permafrost thaw and fossil fuel emissions shifts at annual and seasonal time scales, even in the presence of transport errors, representativeness errors, and biogenic flux errors. While OCO-2 can detect some of these perturbations at the annual scale, the seasonal sampling provided by ASCENDS provides the stronger constraint.

  6. CHROMOSPHERIC MASS MOTIONS AND INTRINSIC SUNSPOT ROTATIONS FOR NOAA ACTIVE REGIONS 10484, 10486, AND 10488 USING ISOON DATA

    International Nuclear Information System (INIS)

    Hardersen, Paul S.; Balasubramaniam, K. S.; Shkolyar, Svetlana

    2013-01-01

    This work utilizes Improved Solar Observing Optical Network continuum (630.2 nm) and Hα (656.2 nm) data to: (1) detect and measure intrinsic sunspot rotations occurring in the photosphere and chromosphere, (2) identify and measure chromospheric filament mass motions, and (3) assess any large-scale photospheric and chromospheric mass couplings. Significant results from 2003 October 27-29, using the techniques of Brown et al., indicate significant counter-rotation between the two large sunspots in NOAA AR 10486 on October 29, as well as discrete filament mass motions in NOAA AR 10484 on October 27 that appear to be associated with at least one C-class solar flare

  7. Critical flux determination by flux-stepping

    DEFF Research Database (Denmark)

    Beier, Søren; Jonsson, Gunnar Eigil

    2010-01-01

    In membrane filtration related scientific literature, often step-by-step determined critical fluxes are reported. Using a dynamic microfiltration device, it is shown that critical fluxes determined from two different flux-stepping methods are dependent upon operational parameters such as step...... length, step height, and.flux start level. Filtrating 8 kg/m(3) yeast cell suspensions by a vibrating 0.45 x 10(-6) m pore size microfiltration hollow fiber module, critical fluxes from 5.6 x 10(-6) to 1.2 x 10(-5) m/s have been measured using various step lengths from 300 to 1200 seconds. Thus......, such values are more or less useless in itself as critical flux predictors, and constant flux verification experiments have to be conducted to check if the determined critical fluxes call predict sustainable flux regimes. However, it is shown that using the step-by-step predicted critical fluxes as start...

  8. Mass balance of arsenic fluxes in rivers impacted by gold mining activities in Paracatu (Minas Gerais State, Brazil).

    Science.gov (United States)

    Bidone, Edison; Cesar, Ricardo; Santos, Maria Carla; Sierpe, Ricardo; Silva-Filho, Emmanuel Vieira; Kutter, Vinicius; Dias da Silva, Lílian I; Castilhos, Zuleica

    2018-03-01

    Arsenic (As) is a dangerous and carcinogenic element and drinking water is its main pathway of human exposure. Gold mines are widely recognized as important sources of As pollution. This work proposes the assessment of As distribution along watersheds surrounding "Morro do Ouro" gold mine (Paracatu, southeastern Brazil). A balance approach between filtered As fluxes (As river segments was applied. Ultrafiltration procedure was used to categorize As into the following classes: particulate > 0.1 μm, colloidal  10 kDa, dissolved  1 kDa, and truly dissolved river segment that suggests As accumulation in sediments along the rivers in both urban and rural areas, mainly due to SPM sedimentation and sorption by Fe oxyhydroxides. Ultrafiltration shattering showed concentrations of decreasing As with particle size; the SPM load (> 0.1 μm) was almost one order higher to dissolved load (< 1 kDa).

  9. Initiation and propagation of damage in actively cooled CFC armoured high heat flux components in fusion machines

    International Nuclear Information System (INIS)

    Chevet, G.; Schlosser, J.; Martin, E.; Herb, V.; Camus, G.; Escourbiac, F.

    2009-01-01

    Plasma facing components (PFCs) in magnetic confinement controlled fusion machines are armoured with carbon fibre composite (CFC) bonded to a copper alloy heat sink. The manufacturing process induces high level of residual stresses due to the thermal expansion mismatch between CFC and copper and PFCs have to withstand strong stress ranges during operation. To study the initiation and propagation of damage in the CFC part, the ONERA damage model is used to describe the behaviour of the N11 material. The finite element simulations show that the damage is located near the interface and develops during the manufacturing of the PFCs as a consequence of the high amplitude of shear stresses. Under high heat flux, stresses decrease and the damage does not evolve. Further studies will take into account the damageable behaviour of the composite/copper interface, which will lead to geometrical optimisations and better knowledge of the link between damage and conductivity.

  10. On the Ability of Space- Based Passive and Active Remote Sensing Observations of CO2 to Detect Flux Perturbations to the Carbon Cycle

    Science.gov (United States)

    Crowell, Sean M. R.; Kawa, S. Randolph; Browell, Edward V.; Hammerling, Dorit M.; Moore, Berrien; Schaefer, Kevin; Doney, Scott C.

    2018-01-01

    Space-borne observations of CO2 are vital to gaining understanding of the carbon cycle in regions of the world that are difficult to measure directly, such as the tropical terrestrial biosphere, the high northern and southern latitudes, and in developing nations such as China. Measurements from passive instruments such as GOSAT (Greenhouse Gases Observing Satellite) and OCO-2 (Orbiting Carbon Observatory 2), however, are constrained by solar zenith angle limitations as well as sensitivity to the presence of clouds and aerosols. Active measurements such as those in development for the Active Sensing of CO2 Emissions over Nights, Days and Seasons (ASCENDS) mission show strong potential for making measurements in the high-latitude winter and in cloudy regions. In this work we examine the enhanced flux constraint provided by the improved coverage from an active measurement such as ASCENDS. The simulation studies presented here show that with sufficient precision, ASCENDS will detect permafrost thaw and fossil fuel emissions shifts at annual and seasonal time scales, even in the presence of transport errors, representativeness errors, and biogenic flux errors. While OCO-2 can detect some of these perturbations at the annual scale, the seasonal sampling provided by ASCENDS provides the stronger constraint. Plain Language Summary: Active and passive remote sensors show the potential to provide unprecedented information on the carbon cycle. With the all-season sampling, active remote sensors are more capable of constraining high-latitude emissions. The reduced sensitivity to cloud and aerosol also makes active sensors more capable of providing information in cloudy and polluted scenes with sufficient accuracy. These experiments account for errors that are fundamental to the top-down approach for constraining emissions, and even including these sources of error, we show that satellite remote sensors are critical for understanding the carbon cycle.

  11. EFFECTS OF FATIGUE ON FRONTAL PLANE KNEE MOTION, MUSCLE ACTIVITY, AND GROUND REACTION FORCES IN MEN AND WOMEN DURING LANDING

    Directory of Open Access Journals (Sweden)

    Michael P. Smith

    2009-09-01

    Full Text Available Women tear their Anterior Cruciate Ligament (ACL 2-8 times more frequently than men. Frontal plane knee motion can produce a pathological load in the ACL. During a state of fatigue the muscles surrounding the knee joint may lose the ability to protect the joint during sudden deceleration while landing. The purpose of this study was to investigate the effects of fatigue and gender on frontal plane knee motion, EMG amplitudes, and GRF magnitudes during drop- jump landing. Pretest-posttest comparison group design was used. Twenty-six volunteers (14 women; 12 Men; Mean ± standard deviation age = 24.5 ± 2.7 yrs; height = 1.73 ± 0.09 m; mass = 74.3 ± 11.8 kg participated in the study. Knee frontal plane ranges of motion and positions, ground reaction force peak magnitudes, and surface EMG RMS amplitudes from five lower extremity muscles (vastus medialis, vastus lateralis, medial hamstring, lateral hamstring, and lateral gastrocnemius were obtained during the landing phase of a drop-jump. MANOVA and ANOVA indicated that peak GRF significantly (p < 0.05; 2.50 ± 0.75 BW vs. 2.06 ± 0.93 BW decreased during fatigued landings. No other variables exhibited a fatigue main effect, although there was a significant (p < 0.05 fatigue by gender interaction for the frontal plane range of motion from initial contact to max knee flexion variable. Follow-up analyses failed to reveal significant gender differences at the different levels of fatigue for this variable. Additionally, no variables exhibited a significant gender main effect. Single subject analysis indicated that fatigue significantly altered frontal plane knee motion, peak GRF, and EMG in some subjects and the direction of differences varied by individual. Fatigue altered some aspects of landing performance in both men and women, but there were no gender differences. Additionally, both group and single subject analyses provided valuable but different information about factors representing

  12. Evaluation of the combined effects of target size, respiratory motion and background activity on 3D and 4D PET/CT images

    International Nuclear Information System (INIS)

    Park, Sang-June; Ionascu, Dan; Killoran, Joseph; Chin, Lee; Berbeco, Ross; Mamede, Marcelo; Gerbaudo, Victor H

    2008-01-01

    Gated (4D) PET/CT has the potential to greatly improve the accuracy of radiotherapy at treatment sites where internal organ motion is significant. However, the best methodology for applying 4D-PET/CT to target definition is not currently well established. With the goal of better understanding how to best apply 4D information to radiotherapy, initial studies were performed to investigate the effect of target size, respiratory motion and target-to-background activity concentration ratio (TBR) on 3D (ungated) and 4D PET images. Using a PET/CT scanner with 4D or gating capability, a full 3D-PET scan corrected with a 3D attenuation map from 3D-CT scan and a respiratory gated (4D) PET scan corrected with corresponding attenuation maps from 4D-CT were performed by imaging spherical targets (0.5-26.5 mL) filled with 18 F-FDG in a dynamic thorax phantom and NEMA IEC body phantom at different TBRs (infinite, 8 and 4). To simulate respiratory motion, the phantoms were driven sinusoidally in the superior-inferior direction with amplitudes of 0, 1 and 2 cm and a period of 4.5 s. Recovery coefficients were determined on PET images. In addition, gating methods using different numbers of gating bins (1-20 bins) were evaluated with image noise and temporal resolution. For evaluation, volume recovery coefficient, signal-to-noise ratio and contrast-to-noise ratio were calculated as a function of the number of gating bins. Moreover, the optimum thresholds which give accurate moving target volumes were obtained for 3D and 4D images. The partial volume effect and signal loss in the 3D-PET images due to the limited PET resolution and the respiratory motion, respectively were measured. The results show that signal loss depends on both the amplitude and pattern of respiratory motion. However, the 4D-PET successfully recovers most of the loss induced by the respiratory motion. The 5-bin gating method gives the best temporal resolution with acceptable image noise. The results based on the 4D

  13. The influence of the number of activation detectors on the Seibersdorf - Milano intercomparison of neutron flux density spectra by WINDOWS code

    International Nuclear Information System (INIS)

    Ertek, C.

    1981-02-01

    This work is a continuation of the work performed within the IAEA programme on standardization of reactor radiation measurements, one of the important objectives of which is the assistance to laboratories in Member States to implement or intercompare the multiple foil activation techniques for different neutron field measurements. The importance of these techniques is well recognized. In CESNEF-FERMI Politecnico di Milano, Italy, they have installed near the core of a water boiler of 50kW, a neutron filter made of B 4 C in order to obtain a neutron flux density spectrum that could be of utility in intercalibration problems connected with irradiation in fast assemblies. Dr. V. Sangiust from CESNEF kindly sent the input guess neutron flux density spectrum and a series of measured reaction rates to be treated by the IAEA Seibersdorf laboratory using the SAND-II and the WINDOWS unfolding codes. The meaningful comparison using partly the same ENDF/B IV cross section data is performed. In the present work we extended the investiga tion using WINDOWS unfolding code for different numbers of activation fo ils or reaction rates

  14. FLUX CANCELLATION AND THE EVOLUTION OF THE ERUPTIVE FILAMENT OF 2011 JUNE 7

    Energy Technology Data Exchange (ETDEWEB)

    Yardley, S. L.; Green, L. M.; Williams, D. R.; Van Driel-Gesztelyi, L.; Valori, G.; Dacie, S., E-mail: stephanie.yardley.13@ucl.ac.uk [Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey RH5 6NT (United Kingdom)

    2016-08-20

    We investigate whether flux cancellation is responsible for the formation of a very massive filament resulting in the spectacular eruption on 2011 June 7. We analyze and quantify the amount of flux cancellation that occurs in NOAA AR 11226 and its two neighboring active regions (ARs 11227 and 11233) using line-of-sight magnetograms from the Heliospheric Magnetic Imager. During a 3.6 day period building up to the eruption of the filament, 1.7 × 10{sup 21} Mx, 21% of AR 11226's maximum magnetic flux, was canceled along the polarity inversion line (PIL) where the filament formed. If the flux cancellation continued at the same rate up until the eruption then up to 2.8 × 10{sup 21} Mx (34% of the AR flux) may have been built into the magnetic configuration that contains the filament plasma. The large flux cancellation rate is due to an unusual motion of the positive-polarity sunspot, which splits, with the largest section moving rapidly toward the PIL. This motion compresses the negative polarity and leads to the formation of an orphan penumbra where one end of the filament is rooted. Dense plasma threads above the orphan penumbra build into the filament, extending its length, and presumably injecting material into it. We conclude that the exceptionally strong flux cancellation in AR 11226 played a significant role in the formation of its unusually massive filament. In addition, the presence and coherent evolution of bald patches in the vector magnetic field along the PIL suggest that the magnetic field configuration supporting the filament material is that of a flux rope.

  15. Communication: On the calculation of time-dependent electron flux within the Born-Oppenheimer approximation: A flux-flux reflection principle

    Science.gov (United States)

    Albert, Julian; Hader, Kilian; Engel, Volker

    2017-12-01

    It is commonly assumed that the time-dependent electron flux calculated within the Born-Oppenheimer (BO) approximation vanishes. This is not necessarily true if the flux is directly determined from the continuity equation obeyed by the electron density. This finding is illustrated for a one-dimensional model of coupled electronic-nuclear dynamics. There, the BO flux is in perfect agreement with the one calculated from a solution of the time-dependent Schrödinger equation for the coupled motion. A reflection principle is derived where the nuclear BO flux is mapped onto the electronic flux.

  16. Regarding "Semi-active control of the rocking motion of monolithic art objects" [Journal of Sound and Vibration, 374 (2016) 1-16

    Science.gov (United States)

    Cartmell, Matthew P.

    2016-09-01

    The Editor wishes to make the reader aware that the paper "Semi-active control of the rocking motion of monolithic art objects" by R. Ceravolo, M.L. Pecorelli, and L.Z. Fragonara, did not contain a direct citation of the fundamental and original work by D. Konstantinidis and N. Makris entitled "Experimental and analytical studies on the seismic response of free-standing and anchored laboratory equipment", Report No. PEER 2005/07. Pacific Earthquake Engineering Research (PEER) Center, University of California, Berkeley, 2005. The Editor regrets that this omission was not noted at the time that the above paper was accepted and published.

  17. Effect of post weld heat treatment on the microstructure and tensile properties of activated flux TIG welds of Inconel X750

    Energy Technology Data Exchange (ETDEWEB)

    Ramkumar, K. Devendranath, E-mail: ramdevendranath@gmail.com; Ramanand, R.; Ameer, Ajmal; Simon, K. Aghil; Arivazhagan, N.

    2016-03-21

    This study addresses the effect of post weld heat treatment on the fusion zone microstructure and the mechanical properties of activated flux tungsten inert gas (A-TIG) weldments of Inconel X750. In this study, a compound flux of 50% SiO{sub 2}+50% MoO{sub 3} was used for A-TIG welding of the samples. Comparative studies on the microstructure and mechanical properties have been made on the weldments both in the as-welded and post weld heat treated conditions. Direct ageing post weld heat treatment (PWHT) was carried out at 705 °C for 22 h on the A-TIG weldment to assess the structure–property relationships. It was inferred that direct ageing post weld heat treatment resulted in better tensile strength (1142 MPa) compared to the as-welded coupons (736 MPa). The joint efficiencies of the as-welded and post weld heat treated conditions were found to be 60.7% and 94.07% respectively. The impact toughness of the as-welded coupons were found to be greater than the post weld heat treated samples; however the impact toughness of the welds are greater than the parent metal employed in both the cases. This study also attested the detailed structure–property relationships of A-TIG weldments using the combined techniques of optical and scanning electron microscopy, Electron Dispersive X-ray Analysis (EDAX) techniques.

  18. Effect of post weld heat treatment on the microstructure and tensile properties of activated flux TIG welds of Inconel X750

    International Nuclear Information System (INIS)

    Ramkumar, K. Devendranath; Ramanand, R.; Ameer, Ajmal; Simon, K. Aghil; Arivazhagan, N.

    2016-01-01

    This study addresses the effect of post weld heat treatment on the fusion zone microstructure and the mechanical properties of activated flux tungsten inert gas (A-TIG) weldments of Inconel X750. In this study, a compound flux of 50% SiO_2+50% MoO_3 was used for A-TIG welding of the samples. Comparative studies on the microstructure and mechanical properties have been made on the weldments both in the as-welded and post weld heat treated conditions. Direct ageing post weld heat treatment (PWHT) was carried out at 705 °C for 22 h on the A-TIG weldment to assess the structure–property relationships. It was inferred that direct ageing post weld heat treatment resulted in better tensile strength (1142 MPa) compared to the as-welded coupons (736 MPa). The joint efficiencies of the as-welded and post weld heat treated conditions were found to be 60.7% and 94.07% respectively. The impact toughness of the as-welded coupons were found to be greater than the post weld heat treated samples; however the impact toughness of the welds are greater than the parent metal employed in both the cases. This study also attested the detailed structure–property relationships of A-TIG weldments using the combined techniques of optical and scanning electron microscopy, Electron Dispersive X-ray Analysis (EDAX) techniques.

  19. Feasibility of Using Low-Cost Motion Capture for Automated Screening of Shoulder Motion Limitation after Breast Cancer Surgery.

    Directory of Open Access Journals (Sweden)

    Valeriya Gritsenko

    Full Text Available To determine if a low-cost, automated motion analysis system using Microsoft Kinect could accurately measure shoulder motion and detect motion impairments in women following breast cancer surgery.Descriptive study of motion measured via 2 methods.Academic cancer center oncology clinic.20 women (mean age = 60 yrs were assessed for active and passive shoulder motions during a routine post-operative clinic visit (mean = 18 days after surgery following mastectomy (n = 4 or lumpectomy (n = 16 for breast cancer.Participants performed 3 repetitions of active and passive shoulder motions on the side of the breast surgery. Arm motion was recorded using motion capture by Kinect for Windows sensor and on video. Goniometric values were determined from video recordings, while motion capture data were transformed to joint angles using 2 methods (body angle and projection angle.Correlation of motion capture with goniometry and detection of motion limitation.Active shoulder motion measured with low-cost motion capture agreed well with goniometry (r = 0.70-0.80, while passive shoulder motion measurements did not correlate well. Using motion capture, it was possible to reliably identify participants whose range of shoulder motion was reduced by 40% or more.Low-cost, automated motion analysis may be acceptable to screen for moderate to severe motion impairments in active shoulder motion. Automatic detection of motion limitation may allow quick screening to be performed in an oncologist's office and trigger timely referrals for rehabilitation.

  20. Feasibility of Using Low-Cost Motion Capture for Automated Screening of Shoulder Motion Limitation after Breast Cancer Surgery.

    Science.gov (United States)

    Gritsenko, Valeriya; Dailey, Eric; Kyle, Nicholas; Taylor, Matt; Whittacre, Sean; Swisher, Anne K

    2015-01-01

    To determine if a low-cost, automated motion analysis system using Microsoft Kinect could accurately measure shoulder motion and detect motion impairments in women following breast cancer surgery. Descriptive study of motion measured via 2 methods. Academic cancer center oncology clinic. 20 women (mean age = 60 yrs) were assessed for active and passive shoulder motions during a routine post-operative clinic visit (mean = 18 days after surgery) following mastectomy (n = 4) or lumpectomy (n = 16) for breast cancer. Participants performed 3 repetitions of active and passive shoulder motions on the side of the breast surgery. Arm motion was recorded using motion capture by Kinect for Windows sensor and on video. Goniometric values were determined from video recordings, while motion capture data were transformed to joint angles using 2 methods (body angle and projection angle). Correlation of motion capture with goniometry and detection of motion limitation. Active shoulder motion measured with low-cost motion capture agreed well with goniometry (r = 0.70-0.80), while passive shoulder motion measurements did not correlate well. Using motion capture, it was possible to reliably identify participants whose range of shoulder motion was reduced by 40% or more. Low-cost, automated motion analysis may be acceptable to screen for moderate to severe motion impairments in active shoulder motion. Automatic detection of motion limitation may allow quick screening to be performed in an oncologist's office and trigger timely referrals for rehabilitation.

  1. Two activities with a simple model of the solar system: discovering Kepler’s 3rd law and investigating apparent motion of Venus

    Science.gov (United States)

    Rovšek, Barbara; Guštin, Andrej

    2018-01-01

    An astronomy ‘experiment’ composed of three parts is described in the article. Being given necessary data a simple model of inner planets of the solar system is made in the first part with planets’ circular orbits using appropriate scale. In the second part revolution of the figurines used as model representations of the planets along their orbits is observed. In the third part of activity apparent motion of Venus with respect to the observer on the Earth is studied. In the second part of the paper problems are given, which relate to experimental activities and are designed to test if learning outcomes of the experiment have been achieved: if correlation between orbital radius and orbital velocity has been perceived, concepts related to motion of Venus as observed from the Earth have been acquired and periodicity recognized. Described astronomy ‘experiment’ was one of the three science experiments given to 11 and 12 years old students prior to Slovene science competition in 2017 (the call for competition is at www.dmfa.si, guidelines for the experiment (in Slovene) can be found at www.kresnickadmfa.si/files/2016/07/poskus_1617_r67p1_S.pdf). At the end of the paper the results obtained at competition are presented.

  2. Absolute measurement of a standard thermal-neutron flux using gold-detector activation; Mesure absolue d'un flux etalon de neutrons thermiques par activation de detecteurs d'or

    Energy Technology Data Exchange (ETDEWEB)

    Paternot, Y [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1967-02-15

    The density of neutrons in a standard stacking is determined between the zero-energy and the cut-off energy of 1 mm thick cadmium unit using a gold detector. Its absolute activity is measured using a 4 {pi} {beta} counter calibrated for 4 {pi} {beta},{gamma} coincidence by counting strongly active sources. The correction factor F due to the disintegration process for the gold is determined experimentally. {phi}{sub 0} = N{sub 0} {sup E}Cd{sub V0} = 6495 {+-} 1.5 per cent n/cm{sup 2}/s. (author) [French] La densite de neutrons dans un empilement etalon est determinee entre l'energie zero et l'energie de coupure d'un boitier de cadmium de 1 mm d'epaisseur au moyen d'un detecteur d'or. Son activite absolue est mesuree a l'aide d'un compteur 4 {pi} {beta} etalonne en coincidence 4 {pi} {beta},{gamma} par comptage de sources fortement actives. Le facteur de correction F d au schema de desintegration de l'or est determine experimentalement. {phi}{sub 0} = N{sub 0} {sup E}Cd{sub V0} = 6495 {+-} 1.5 pour cent n/cm{sup 2}/s. (auteur)

  3. Notes on neutron flux measurement

    International Nuclear Information System (INIS)

    Alcala Ruiz, F.

    1984-01-01

    The main purpose of this work is to get an useful guide to carry out topical neutron flux measurements. Although the foil activation technique is used in the majority of the cases, other techniques, such as those based on fission chambers and self-powered neutron detectors, are also shown. Special interest is given to the description and application of corrections on the measurement of relative and absolute induced activities by several types of detectors (scintillators, G-M and gas proportional counters). The thermal arid epithermal neutron fluxes, as determined in this work, are conventional or effective (West cots fluxes), which are extensively used by the reactor experimentalists; however, we also give some expressions where they are related to the integrated neutron fluxes, which are used in neutron calculations. (Author) 16 refs

  4. Biological Motion induced mu suppression is reduced in Early Psychosis (EP) patients with active negative symptoms and Autism Spectrum Disorders (ASD).

    Science.gov (United States)

    Minichino, Amedeo; Singh, Fiza; Pineda, Jaime; Friederich, Elisabeth; Cadenhead, Kristin S

    2016-04-30

    There is evidence of genetic and neural system overlap in Autism Spectrum Disorder (ASD) and Early Psychosis (EP). Five datasets were pooled to compare mu suppression index (MSI), a proxy of mirror neuron activity, in EP, high functioning ASD, and healthy subjects (HS). ASDs and EPs with "active" negative symptoms showed significant differences in mu suppression, in response to Biological Motion/point-light display animation, compared to HS. Preliminary findings suggest that similar neural network deficits in ASD and EP could be driven by the expression of negative symptoms in the latter group of patients. These findings may aid future studies on EP and ASD and facilitate the formulation of new hypotheses regarding their pathophysiology. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  5. LIGHT BRIDGE IN A DEVELOPING ACTIVE REGION. II. NUMERICAL SIMULATION OF FLUX EMERGENCE AND LIGHT BRIDGE FORMATION

    International Nuclear Information System (INIS)

    Toriumi, Shin; Katsukawa, Yukio; Cheung, Mark C. M.

    2015-01-01

    Light bridges, the bright structure dividing umbrae in sunspot regions, show various activity events. In Paper I, we reported on an analysis of multi-wavelength observations of a light bridge in a developing active region (AR) and concluded that the activity events are caused by magnetic reconnection driven by magnetconvective evolution. The aim of this second paper is to investigate the detailed magnetic and velocity structures and the formation mechanism of light bridges. For this purpose, we analyze numerical simulation data from a radiative magnetohydrodynamics model of an emerging AR. We find that a weakly magnetized plasma upflow in the near-surface layers of the convection zone is entrained between the emerging magnetic bundles that appear as pores at the solar surface. This convective upflow continuously transports horizontal fields to the surface layer and creates a light bridge structure. Due to the magnetic shear between the horizontal fields of the bridge and the vertical fields of the ambient pores, an elongated cusp-shaped current layer is formed above the bridge, which may be favorable for magnetic reconnection. The striking correspondence between the observational results of Paper I and the numerical results of this paper provides a consistent physical picture of light bridges. The dynamic activity phenomena occur as a natural result of the bridge formation and its convective nature, which has much in common with those of umbral dots and penumbral filaments

  6. Validity of a combined heart rate and motion sensor for the measurement of free-living energy expenditure in very active individuals.

    Science.gov (United States)

    Santos, Diana A; Silva, Analiza M; Matias, Catarina N; Magalhães, João P; Fields, David A; Minderico, Cláudia S; Ekelund, Ulf; Sardinha, Luís B

    2014-07-01

    The correct assessment of energy expenditure in very active individuals is important to ensure that dietary energy intake is sufficient. We aimed to validate a combined heart rate (HR) and motion sensor in estimating total (TEE) and activity energy expenditure (AEE) in males and females with high physical activity levels. Cross-sectional. Doubly-labelled water (DLW) was used to assess 7-day TEE in 12 male and female elite junior basketball players, aged 16-17 years. Resting energy expenditure (REE) was assessed with indirect calorimetry and AEE was calculated (AEE=TEE-RMR-0.1×TEE). Simultaneously, TEE and AEE were measured by combined HR and motion sensing. Individual HR calibration was performed with step-test. TEE and AEE were estimated from accelerometry and HR with individual (ACC+HRstep) and group calibration (ACC+HRgroup). No mean differences were found between TEE and AEE from the ACC+HRstep and ACC+HRgroup with DLW. TEE values (kJ/day) from ACC+HRgroup and ACC+HRstep explained TEE from DLW by ∼60% and 53%, respectively whereas AEE (kJ/day) estimated by ACC+HRgroup and ACC+HRstep explained 53% and 41% of the variability of AEE from the reference method. Concordance correlation coefficients for TEE and AEE using ACC+HRgroup were 0.74 and 0.69, correspondingly while for ACC+HRstep values of 0.69 and 0.45 were found. Large limits of agreement were found for TEE and AEE using both ACC+HRgroup and ACC+HRstep. ACC+HR models are a valid alternative to estimate TEE but not AEE in a group of highly active individuals however the considerable rate of equipment failure (∼50%) limits its usefulness. Copyright © 2013 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  7. Four-collector flux sensor

    International Nuclear Information System (INIS)

    Wiegand, W.J. Jr.; Bullis, R.H.; Mongeon, R.J.

    1980-01-01

    A flowmeter based on ion drift techniques was developed for measuring the rate of flow of a fluid through a given cross-section. Ion collectors are positioned on each side of an immediately adjacent to ion source. When air flows axially through the region in which ions are produced and appropriate electric fields are maintained between the collectors, an electric current flows to each collector due to the net motion of the ions. The electric currents and voltages and other parameters which define the flow are combined in an electric circuit so that the flux of the fluid can be determined. (DN)

  8. Simulated Microgravity Reduces TNF-Alpha Activity, Suppresses Glucose Uptake and Enhances Arginine Flux in Pancreatic Islets of Langerhans

    Science.gov (United States)

    Tobin, Brian W.; Leeper-Woodford, Sandra K.; Hashemi, Brian B.; Smith, Scott M.; Sams, Clarence F.; Paloski, W. H. (Technical Monitor)

    2000-01-01

    The present studies were designed to determine effects of microgravity upon lipopolysaccharide (LPS) stimulated tumor necrosis factor alpha (TNF - alpha) activity and indices of insulin and fuel homeostasis of pancreatic islets of Langerhans. Islets (1726+/-117,150 u IEU) from Wistar Furth rats were treated as: 1) HARV (High Aspect Ratio Vessel cell culture) , 2) HARV plus LPS 3) static culture, 4) static culture plus LPS TNF-alpha (L929 cytotoxicity assay) was significantly increased in LPS-induced HARV and static cultures, yet the increase was more pronounced in the static culture group (palpha production of pancreatic islets of Langerhans, favoring a lesser TNF activity in the HARV paradigm. These alterations in fuel homeostasis may be promulgated by gravity averaged cell culture methods or by three dimensional cell assembly.

  9. Proton Fluxes Measured by the PAMELA Experiment from the Minimum to the Maximum Solar Activity for Solar Cycle 24

    Science.gov (United States)

    Martucci, M.; Munini, R.; Boezio, M.; Di Felice, V.; Adriani, O.; Barbarino, G. C.; Bazilevskaya, G. A.; Bellotti, R.; Bongi, M.; Bonvicini, V.; Bottai, S.; Bruno, A.; Cafagna, F.; Campana, D.; Carlson, P.; Casolino, M.; Castellini, G.; De Santis, C.; Galper, A. M.; Karelin, A. V.; Koldashov, S. V.; Koldobskiy, S.; Krutkov, S. Y.; Kvashnin, A. N.; Leonov, A.; Malakhov, V.; Marcelli, L.; Marcelli, N.; Mayorov, A. G.; Menn, W.; Mergè, M.; Mikhailov, V. V.; Mocchiutti, E.; Monaco, A.; Mori, N.; Osteria, G.; Panico, B.; Papini, P.; Pearce, M.; Picozza, P.; Ricci, M.; Ricciarini, S. B.; Simon, M.; Sparvoli, R.; Spillantini, P.; Stozhkov, Y. I.; Vacchi, A.; Vannuccini, E.; Vasilyev, G.; Voronov, S. A.; Yurkin, Y. T.; Zampa, G.; Zampa, N.; Potgieter, M. S.; Raath, J. L.

    2018-02-01

    Precise measurements of the time-dependent intensity of the low-energy (solar activity periods, i.e., from minimum to maximum, are needed to achieve comprehensive understanding of such physical phenomena. The minimum phase between solar cycles 23 and 24 was peculiarly long, extending up to the beginning of 2010 and followed by the maximum phase, reached during early 2014. In this Letter, we present proton differential spectra measured from 2010 January to 2014 February by the PAMELA experiment. For the first time the GCR proton intensity was studied over a wide energy range (0.08–50 GeV) by a single apparatus from a minimum to a maximum period of solar activity. The large statistics allowed the time variation to be investigated on a nearly monthly basis. Data were compared and interpreted in the context of a state-of-the-art three-dimensional model describing the GCRs propagation through the heliosphere.

  10. High-flux white neutron source based on p(35)-Be reactions for activation experiments at NPI

    Czech Academy of Sciences Publication Activity Database

    Štefánik, Milan; Bém, Pavel; Götz, Miloslav; Katovsky, K.; Majerle, Mitja; Novák, Jan; Šimečková, Eva

    2014-01-01

    Roč. 104, NOV (2014), s. 306-309 ISSN 0969-806X. [1st International Conference on Dosimetry and its Applications (ICDA). Prague, 23.6.2013-28.6.2013] R&D Projects: GA MŠk(XE) LM2011019 Institutional support: RVO:61389005 Keywords : neutron generator * accelerator * dosimetry foils activation method * neutron spectrometry * Gamma-spectrometry * reaction rate Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.380, year: 2014

  11. Dissociation from DNA of Type III Restriction–Modification enzymes during helicase-dependent motion and following endonuclease activity

    Science.gov (United States)

    Tóth, Júlia; van Aelst, Kara; Salmons, Hannah; Szczelkun, Mark D.

    2012-01-01

    DNA cleavage by the Type III Restriction–Modification (RM) enzymes requires the binding of a pair of RM enzymes at two distant, inversely orientated recognition sequences followed by helicase-catalysed ATP hydrolysis and long-range communication. Here we addressed the dissociation from DNA of these enzymes at two stages: during long-range communication and following DNA cleavage. First, we demonstrated that a communicating species can be trapped in a DNA domain without a recognition site, with a non-specific DNA association lifetime of ∼200 s. If free DNA ends were present the lifetime became too short to measure, confirming that ends accelerate dissociation. Secondly, we observed that Type III RM enzymes can dissociate upon DNA cleavage and go on to cleave further DNA molecules (they can ‘turnover’, albeit inefficiently). The relationship between the observed cleavage rate and enzyme concentration indicated independent binding of each site and a requirement for simultaneous interaction of at least two enzymes per DNA to achieve cleavage. In light of various mechanisms for helicase-driven motion on DNA, we suggest these results are most consistent with a thermally driven random 1D search model (i.e. ‘DNA sliding’). PMID:22523084

  12. Enhanced particle fluxes and heterotrophic bacterial activities in Gulf of Mexico bottom waters following storm-induced sediment resuspension

    Science.gov (United States)

    Ziervogel, K.; Dike, C.; Asper, V.; Montoya, J.; Battles, J.; D`souza, N.; Passow, U.; Diercks, A.; Esch, M.; Joye, S.; Dewald, C.; Arnosti, C.

    2016-07-01

    Bottom nepheloid layers (BNLs) in the deep sea transport and remobilize considerable amounts of particulate matter, enhancing microbial cycling of organic matter in cold, deep water environments. We measured bacterial abundance, bacterial protein production, and activities of hydrolytic enzymes within and above a BNL that formed in the deep Mississippi Canyon, northern Gulf of Mexico, shortly after Hurricane Isaac had passed over the study area in late August 2012. The BNL was detected via beam attenuation in CTD casts over an area of at least 3.5 km2, extending up to 200 m above the seafloor at a water depth of 1500 m. A large fraction of the suspended matter in the BNL consisted of resuspended sediments, as indicated by high levels of lithogenic material collected in near-bottom sediment traps shortly before the start of our sampling campaign. Observations of suspended particle abundance and sizes throughout the water column, using a combined camera-CTD system (marine snow camera, MSC), revealed the presence of macroaggregates (>1 mm in diameter) within the BNL, indicating resuspension of canyon sediments. A distinct bacterial response to enhanced particle concentrations within the BNL was evident from the observation that the highest enzymatic activities (peptidase, β-glucosidase) and protein production (3H-leucine incorporation) were found within the most particle rich sections of the BNL. To investigate the effects of enhanced particle concentrations on bacterial activities in deep BNLs more directly, we conducted laboratory experiments with roller bottles filled with bottom water and amended with experimentally resuspended sediments from the study area. Macroaggregates formed within 1 day from resuspended sediments; by day 4 of the incubation bacterial cell numbers in treatments with resuspended sediments were more than twice as high as in those lacking sediment suspensions. Cell-specific enzymatic activities were also generally higher in the sediment

  13. Auditory Motion Elicits a Visual Motion Aftereffect

    Directory of Open Access Journals (Sweden)

    Christopher C. Berger

    2016-12-01

    Full Text Available The visual motion aftereffect is a visual illusion in which exposure to continuous motion in one direction leads to a subsequent illusion of visual motion in the opposite direction. Previous findings have been mixed with regard to whether this visual illusion can be induced cross-modally by auditory stimuli. Based on research on multisensory perception demonstrating the profound influence auditory perception can have on the interpretation and perceived motion of visual stimuli, we hypothesized that exposure to auditory stimuli with strong directional motion cues should induce a visual motion aftereffect. Here, we demonstrate that horizontally moving auditory stimuli induced a significant visual motion aftereffect—an effect that was driven primarily by a change in visual motion perception following exposure to leftward moving auditory stimuli. This finding is consistent with the notion that visual and auditory motion perception rely on at least partially overlapping neural substrates.

  14. Auditory Motion Elicits a Visual Motion Aftereffect.

    Science.gov (United States)

    Berger, Christopher C; Ehrsson, H Henrik

    2016-01-01

    The visual motion aftereffect is a visual illusion in which exposure to continuous motion in one direction leads to a subsequent illusion of visual motion in the opposite direction. Previous findings have been mixed with regard to whether this visual illusion can be induced cross-modally by auditory stimuli. Based on research on multisensory perception demonstrating the profound influence auditory perception can have on the interpretation and perceived motion of visual stimuli, we hypothesized that exposure to auditory stimuli with strong directional motion cues should induce a visual motion aftereffect. Here, we demonstrate that horizontally moving auditory stimuli induced a significant visual motion aftereffect-an effect that was driven primarily by a change in visual motion perception following exposure to leftward moving auditory stimuli. This finding is consistent with the notion that visual and auditory motion perception rely on at least partially overlapping neural substrates.

  15. Auditory motion capturing ambiguous visual motion

    Directory of Open Access Journals (Sweden)

    Arjen eAlink

    2012-01-01

    Full Text Available In this study, it is demonstrated that moving sounds have an effect on the direction in which one sees visual stimuli move. During the main experiment sounds were presented consecutively at four speaker locations inducing left- or rightwards auditory apparent motion. On the path of auditory apparent motion, visual apparent motion stimuli were presented with a high degree of directional ambiguity. The main outcome of this experiment is that our participants perceived visual apparent motion stimuli that were ambiguous (equally likely to be perceived as moving left- or rightwards more often as moving in the same direction than in the opposite direction of auditory apparent motion. During the control experiment we replicated this finding and found no effect of sound motion direction on eye movements. This indicates that auditory motion can capture our visual motion percept when visual motion direction is insufficiently determinate without affecting eye movements.

  16. Active ankle motion may result in changes to the talofibular interval in individuals with chronic ankle instability and ankle sprain copers: a preliminary study.

    Science.gov (United States)

    Croy, Theodore; Cosby, Nicole L; Hertel, Jay

    2013-08-01

    Alterations in talocrural joint arthrokinematics related to repositioning of the talus or fibula following ankle sprain have been reported in radiological and clinical studies. It is unclear if these changes can result from normal active ankle motion. The study objective was to determine if active movement created changes in the sagittal plane talofibular interval in ankles with a history of lateral ankle sprain and instability. Three subject groups [control (n = 17), ankle sprain copers (n = 20), and chronic ankle instability (n = 20)] underwent ultrasound imaging of the anterolateral ankle gutter to identify the lateral malleolus and talus over three trials. Between trials, subjects actively plantar and dorsiflexed the ankle three times. The sagittal plane talofibular interval was assessed by measuring the anteroposterior distance (mm) between the lateral malleolus and talus from an ultrasound image. Between group and trial differences were analyzed with repeated measures analysis of variance and post-hoc t-tests. Fifty-seven subjects participated. A significant group-by-trial interaction was observed (F4,108 = 3.5; P = 0.009). The talofibular interval was increased in both copers [2.4±3.6 mm; 95% confidence interval (CI): 0.73-4.1; P = 0.007] and chronic ankle instability (4.1±4.6 mm; 95% CI: 1.9-6.2; P = 0.001) at trial 3 while no changes were observed in control ankle talar position (0.06±2.8mm; 95% CI: -1.5-1.4; P = 0.93). The talofibular interval increased only in subjects with a history of lateral ankle sprain with large clinical effect sizes observed. These findings suggest that an alteration in the position of the talus or fibula occurred with non-weight bearing sagittal plane motion. These findings may have diagnostic and therapeutic implications for manual therapists.

  17. Axial and radial distribution of neutron fluxes in the irradiation channels of the Ghana Research Reactor-1 using foil activation analysis and Monte Carlo

    International Nuclear Information System (INIS)

    Abrefah, G.R.

    2009-02-01

    The Monte-Carlo method and experimental methods were used to determine the neutron fluxes in the irradiation channels of the Ghana Research Reactor -1. The MCNP5 code was used for this purpose to simulate the radial and axial distribution of the neutron fluxes within all the ten irradiation channels. The results obtained were compared with the experimental results. After the MCNP simulation and experimental procedure, it was observed that axially, the fluxes rise to a peak before falling and then finally leveling out. Axially and radially, it was also observed that the fluxes in the centre of the channels were lower than on the sides. Radially, the fluxes dip in the centre while it increases steadily towards the sides of the channels. The results have shown that there are flux variations within the irradiation channels both axially and radially. (au)

  18. Magnetic-flux pump

    Science.gov (United States)

    Hildebrandt, A. F.; Elleman, D. D.; Whitmore, F. C. (Inventor)

    1966-01-01

    A magnetic flux pump is described for increasing the intensity of a magnetic field by transferring flux from one location to the magnetic field. The device includes a pair of communicating cavities formed in a block of superconducting material, and a piston for displacing the trapped magnetic flux into the secondary cavity producing a field having an intense flux density.

  19. Radon flux measurement methodologies

    International Nuclear Information System (INIS)

    Nielson, K.K.; Rogers, V.C.

    1984-01-01

    Five methods for measuring radon fluxes are evaluated: the accumulator can, a small charcoal sampler, a large-area charcoal sampler, the ''Big Louie'' charcoal sampler, and the charcoal tent sampler. An experimental comparison of the five flux measurement techniques was also conducted. Excellent agreement was obtained between the measured radon fluxes and fluxes predicted from radium and emanation measurements

  20. Motion control report

    CERN Document Server

    2013-01-01

    Please note this is a short discount publication. In today's manufacturing environment, Motion Control plays a major role in virtually every project.The Motion Control Report provides a comprehensive overview of the technology of Motion Control:* Design Considerations* Technologies* Methods to Control Motion* Examples of Motion Control in Systems* A Detailed Vendors List

  1. Effects of McGill stabilization exercises and conventional physiotherapy on pain, functional disability and active back range of motion in patients with chronic non-specific low back pain.

    Science.gov (United States)

    Ghorbanpour, Arsalan; Azghani, Mahmoud Reza; Taghipour, Mohammad; Salahzadeh, Zahra; Ghaderi, Fariba; Oskouei, Ali E

    2018-04-01

    [Purpose] The aim of this study was to compare the effects of "McGill stabilization exercises" and "conventional physiotherapy" on pain, functional disability and active back flexion and extension range of motion in patients with chronic non-specific low back pain. [Subjects and Methods] Thirty four patients with chronic non-specific low back pain were randomly assigned to McGill stabilization exercises group (n=17) and conventional physiotherapy group (n=17). In both groups, patients performed the corresponding exercises for six weeks. The visual analog scale (VAS), Quebec Low Back Pain Disability Scale Questionnaire and inclinometer were used to measure pain, functional disability, and active back flexion and extension range of motion, respectively. [Results] Statistically significant improvements were observed in pain, functional disability, and active back extension range of motion in McGill stabilization exercises group. However, active back flexion range of motion was the only clinical symptom that statistically increased in patients who performed conventional physiotherapy. There was no significant difference between the clinical characteristics while compared these two groups of patients. [Conclusion] The results of this study indicated that McGill stabilization exercises and conventional physiotherapy provided approximately similar improvement in pain, functional disability, and active back range of motion in patients with chronic non-specific low back pain. However, it appears that McGill stabilization exercises provide an additional benefit to patients with chronic non-specific low back, especially in pain and functional disability improvement.

  2. Terahertz Generation & Vortex Motion Control in Superconductors

    Science.gov (United States)

    Nori, Franco

    2005-03-01

    A grand challenge is to controllably generate electromagnetic waves in layered superconducting compounds because of its Terahertz frequency range. We propose [1] four experimentally realizable devices for generating continuous and pulsed THz radiation in a controllable frequency range. We also describe [2-4] several novel devices for controlling the motion of vortices in superconductors, including a reversible rectifier made of a magnetic-superconducting hybrid structure [4]. Finally, we summarize a study [5] of the friction force felt by moving vortices. 1) S. Savel'ev, V. Yampol'skii, A. Rakhmanov, F. Nori, Tunable Terahertz radiation from Josephson vortices, preprint 2) S. Savel'ev and F. Nori, Experimentally realizable devices for controlling the motion of magnetic flux quanta, Nature Mat. 1, 179 (2002) 3) S. Savel'ev, F. Marchesoni, F. Nori, Manipulating small particles, PRL 92, 160602 (2004); B. Zhu, F. Marchesoni, F. Nori, Controlling the motion of magnetic flux quanta, PRL 92, 180602 (2004) 4) J.E. Villegas, et al., Reversible Rectifier that Controls the Motion of Magnetic Flux Quanta, Science 302, 1188 (2003) 5) A. Maeda, et al., Nano-scale friction: kinetic friction of magnetic flux quanta and charge density waves, preprint

  3. Correction Factor Analysis Of Foil Activation And The Effect Of Neglecting The Correction On Neutron Flux And Spectrum Measurement; ANALISIS FAKTOR KOREKSI KEPING AKTIVASI DAN PENGARUH PENGABAIANNYA PADA PENGUKURAN FLUKS DAN SPEKTRUM NEUTRON

    Energy Technology Data Exchange (ETDEWEB)

    Radiyanti, Ita Budi; Hamzah, Amir; Pinem, Surian [Multipurpose Reactor Centre Indonesia, Serpong, (Indonesia)

    1996-04-15

    Foil activation method is commonly used in flux and neutron spectrum measurement in nuclear reactor and other research. The effect of the thickness, type of foil material and neutron spectrum shape on the self shielding correction and activities correction on the edges of the foil have been analyzed. Also the effect of neglecting those correction factors on neutron flux and spectrum measurement were analyzed. The calculation of the correction factor has been done by using the program which had been verified for several foils. The foils used are Au, In. Cu, Co and Dy of 0.00254 cm -0.127 cm thickness and 1.27 cm diameter. The result showed that the correction factor foils were not similar due to the variation of activation cross section and neutron spectrum shape. For the neutron spectrum in RS-2 multi purpose reactor GAS using foils of 0.00254 cm thick. The effect of neglecting correction factor on thermal flux measurement for Au, In, Co and Cu were less than -6%, for Dy was about -25%. On epithermal flux measurement for Au and In were about -60%, Co and Dy was -12% and -6%, for Cu less than -2%. The effect of neglecting correction factor on spectrum measurement was the change on the neutron flux density values along neutron energy region.

  4. Aeolian dune sediment flux heterogeneity in Meridiani Planum, Mars.

    Science.gov (United States)

    Chojnacki, Matthew; Urso, Anna; Fenton, Lori K; Michaels, Timothy I

    2017-06-01

    It is now known unambiguously that wind-driven bedform activity is occurring on the surface of Mars today, including early detections of active sand dunes in Meridiani Planum's Endeavour crater. Many of these reports are only based on a few sets of observations of relatively isolated bedforms and lack regional context. Here, we investigate aeolian activity across central Meridiani Planum and test the hypothesis that dune sites surrounding Endeavour crater are also active and part of region-wide sediment migration driven by northwesterly winds. All 13 dune fields investigated clearly showed evidence for activity and the majority exhibited dune migration (average rates of 0.6 m/Earth-year). Observations indicate substantial geographic and temporal heterogeneity of dune crest fluxes across the area and per site. Locations with multiple time steps indicate dune sand fluxes can vary by a factor of five, providing evidence for short periods of rapid migration followed by near-stagnation. In contrast, measurements at other sites are nearly identical, indicating that some dunes are in a steady-state as they migrate. The observed sediment transport direction was consistent with a regional northeasterly-to-northwesterly wind regime, revealing more variations than were appreciated from earlier, more localized studies. Craters containing shallow, degraded, flat-floored interiors tended to have dunes with high sediment fluxes/activity, whereas local kilometer-scale topographic obstructions (e.g., central peaks, yardangs) were found to be inversely correlated with dune mobility. Finally, the previous, more limited detections of dune activity in Endeavour crater have been shown to be representative of a broader, region-wide pattern of dune motion.

  5. Identification of Flap Motion Parameters for Vibration Reduction in Helicopter Rotors with Multiple Active Trailing Edge Flaps

    OpenAIRE

    Dalli, Uğbreve;ur; Yüksel, Şcedilefaatdin

    2011-01-01

    An active control method utilizing the multiple trailing edge flap configuration for rotorcraft vibration suppression and blade loads control is presented. A comprehensive model for rotor blade with active trailing edge flaps is used to calculate the vibration characteristics, natural frequencies and mode shapes of any complex composite helicopter rotor blade. A computer program is developed to calculate the system response, rotor blade root forces and moments under aerodynamic forcing condit...

  6. Effects of balance training by knee joint motions on muscle activity in adult men with functional ankle instability.

    Science.gov (United States)

    Nam, Seung-Min; Kim, Won-Bok; Yun, Chang-Kyo

    2016-05-01

    [Purpose] This study examined the effects of balance training by applying knee joint movements on muscle activity in male adults with functional ankle instability. [Subjects and Methods] 28 adults with functional ankle instability, divided randomly into an experimental group, which performed balance training by applying knee joint movements for 20 minutes and ankle joint exercises for 10 minutes, and a control group, which performed ankle joint exercise for 30 minutes. Exercises were completed three times a week for 8 weeks. Electromyographic values of the tibialis anterior, peroneus longus, peroneus brevis, and the lateral gastrocnemius muscles were obtained to compare and analyze muscle activity before and after the experiments in each group. [Results] The experimental group had significant increases in muscle activity in the tibialis anterior, peroneus longus, and lateral gastrocnemius muscles, while muscle activity in the peroneus brevis increased without significance. The control group had significant increases in muscle activity in the tibialis anterior and peroneus longus, while muscle activity in the peroneus brevis and lateral gastrocnemius muscles increased without significance. [Conclusion] In conclusion, balance training by applying knee joint movements can be recommended as a treatment method for patients with functional ankle instability.

  7. Long-term predictive assessments of solar and geomagnetic activities made on the basis of the close similarity between the solar inertial motions in the intervals 1840–1905 and 1980–2045

    Czech Academy of Sciences Publication Activity Database

    Charvátová, Ivanka

    2009-01-01

    Roč. 14, č. 1 (2009), s. 25-30 ISSN 1384-1076 R&D Projects: GA AV ČR(CZ) IAA300120608 Institutional research plan: CEZ:AV0Z30120515 Keywords : solar inertial motion * solar activity * geomagnetic activity * long-term predictive assessments Subject RIV: DE - Earth Magnetism, Geodesy, Geography Impact factor: 1.675, year: 2009

  8. The SH2 Domain Regulates c-Abl Kinase Activation by a Cyclin-Like Mechanism and Remodulation of the Hinge Motion

    Science.gov (United States)

    Dölker, Nicole; Górna, Maria W.; Sutto, Ludovico; Torralba, Antonio S.; Superti-Furga, Giulio; Gervasio, Francesco L.

    2014-01-01

    Regulation of the c-Abl (ABL1) tyrosine kinase is important because of its role in cellular signaling, and its relevance in the leukemiogenic counterpart (BCR-ABL). Both auto-inhibition and full activation of c-Abl are regulated by the interaction of the catalytic domain with the Src Homology 2 (SH2) domain. The mechanism by which this interaction enhances catalysis is not known. We combined computational simulations with mutagenesis and functional analysis to find that the SH2 domain conveys both local and global effects on the dynamics of the catalytic domain. Locally, it regulates the flexibility of the αC helix in a fashion reminiscent of cyclins in cyclin-dependent kinases, reorienting catalytically important motifs. At a more global level, SH2 binding redirects the hinge motion of the N and C lobes and changes the conformational equilibrium of the activation loop. The complex network of subtle structural shifts that link the SH2 domain with the activation loop and the active site may be partially conserved with other SH2-domain containing kinases and therefore offer additional parameters for the design of conformation-specific inhibitors. PMID:25299346

  9. The SH2 domain regulates c-Abl kinase activation by a cyclin-like mechanism and remodulation of the hinge motion.

    Science.gov (United States)

    Dölker, Nicole; Górna, Maria W; Sutto, Ludovico; Torralba, Antonio S; Superti-Furga, Giulio; Gervasio, Francesco L

    2014-10-01

    Regulation of the c-Abl (ABL1) tyrosine kinase is important because of its role in cellular signaling, and its relevance in the leukemiogenic counterpart (BCR-ABL). Both auto-inhibition and full activation of c-Abl are regulated by the interaction of the catalytic domain with the Src Homology 2 (SH2) domain. The mechanism by which this interaction enhances catalysis is not known. We combined computational simulations with mutagenesis and functional analysis to find that the SH2 domain conveys both local and global effects on the dynamics of the catalytic domain. Locally, it regulates the flexibility of the αC helix in a fashion reminiscent of cyclins in cyclin-dependent kinases, reorienting catalytically important motifs. At a more global level, SH2 binding redirects the hinge motion of the N and C lobes and changes the conformational equilibrium of the activation loop. The complex network of subtle structural shifts that link the SH2 domain with the activation loop and the active site may be partially conserved with other SH2-domain containing kinases and therefore offer additional parameters for the design of conformation-specific inhibitors.

  10. The SH2 domain regulates c-Abl kinase activation by a cyclin-like mechanism and remodulation of the hinge motion.

    Directory of Open Access Journals (Sweden)

    Nicole Dölker

    2014-10-01

    Full Text Available Regulation of the c-Abl (ABL1 tyrosine kinase is important because of its role in cellular signaling, and its relevance in the leukemiogenic counterpart (BCR-ABL. Both auto-inhibition and full activation of c-Abl are regulated by the interaction of the catalytic domain with the Src Homology 2 (SH2 domain. The mechanism by which this interaction enhances catalysis is not known. We combined computational simulations with mutagenesis and functional analysis to find that the SH2 domain conveys both local and global effects on the dynamics of the catalytic domain. Locally, it regulates the flexibility of the αC helix in a fashion reminiscent of cyclins in cyclin-dependent kinases, reorienting catalytically important motifs. At a more global level, SH2 binding redirects the hinge motion of the N and C lobes and changes the conformational equilibrium of the activation loop. The complex network of subtle structural shifts that link the SH2 domain with the activation loop and the active site may be partially conserved with other SH2-domain containing kinases and therefore offer additional parameters for the design of conformation-specific inhibitors.

  11. Force and motion

    CERN Document Server

    Robertson, William C

    2002-01-01

    Intimidated by inertia? Frightened by forces? Mystified by Newton s law of motion? You re not alone and help is at hand. The stop Faking It! Series is perfect for science teachers, home-schoolers, parents wanting to help with homework all of you who need a jargon-free way to learn the background for teaching middle school physical science with confidence. With Bill Roberton as your friendly, able but somewhat irreverent guide, you will discover you CAN come to grips with the basics of force and motion. Combining easy-to-understand explanations with activities using commonly found equipment, this book will lead you through Newton s laws to the physics of space travel. The book is as entertaining as it is informative. Best of all, the author understands the needs of adults who want concrete examples, hands-on activities, clear language, diagrams and yes, a certain amount of empathy. Ideas For Use Newton's laws, and all of the other motion principles presented in this book, do a good job of helping us to underst...

  12. [Relationship between muscle activity and kinematics of the lower extremity in slow motions of squats in humans].

    Science.gov (United States)

    Khorievin, V I; Horkovenko, A V; Vereshchaka, I V

    2013-01-01

    Squatting can be performed on ankle strategy when ankle joint is flexed more than a hip joint and on hip strategy when large changes occur at the hip joint. The relationships between changes ofjoint angles and electromyogram (EMG) of the leg muscles were studied in five healthy men during squatting that was performed at the ankle and hip strategies with a slow changes in the knee angle of 40 and 60 degrees. It is established that at ankle strategy the ankle muscles were activated ahead of joint angle changes and shifting the center of pressure (CT) on stabilographic platform, whereas activation of the thigh muscles began simultaneously with the change of the joint angles, showing the clear adaptation in successive trials and a linear relationships between the static EMG component and the angle changes of the ankle joint. In the case of hip strategy of squatting the thigh muscles were activated simultaneously with the change in the joint angles and the displacement of CT, whereas the ankle muscles were activated later than the thigh muscles, especially the muscle tibialis anterior, showing some adaptations in consecutive attempts. At the ankle strategy the EMG amplitude was greatest in thigh muscles, reproducing contour of changes in joint angles, whereas the ankle muscles were activated only slightly during changes of joint angles. In the case of hip strategy dominated the EMG amplitude of the muscle tibialis anterior, which was activated when driving down the trunk and fixation of the joint angles that was accompanied by a slight coactivation of the calf muscles with the step-like increase in the amplitude of the EMG of the thigh muscles. Choice of leg muscles to start the squatting on both strategies occurred without a definite pattern, which may indicate the existence of a wide range of options for muscle activity in a single strategy.

  13. Triode for magnetic flux quanta.

    Science.gov (United States)

    Vlasko-Vlasov, Vitalii; Colauto, Fabiano; Benseman, Timothy; Rosenmann, Daniel; Kwok, Wai-Kwong

    We designed a magnetic vortex triode using an array of closely spaced soft magnetic Py strips on top of a Nb superconducting film. The strips act similar to the grid electrode in an electronic triode, where the electron flow is regulated by the grid potential. In our case, we tune the vortex motion by the magnetic charge potential of the strip edges, using a small magnetic field rotating in the film plane. The magnetic charges emerging at the stripe edges and proportional to the magnetization component perpendicular to the edge direction, form linear potential barriers or valleys for vortex motion in the superconducting layer. We directly imaged the normal flux penetration into the Py/Nb films and observed retarded or accelerated entry of the normal vortices depending on the in-plane magnetization direction in the stripes. The observed flux behavior is explained by interactions between magnetically charged lines and magnetic monopoles of vortices similar to those between electrically charged strings and point charges. We discuss the possibility of using our design for manipulation of individual vortices in high-speed, low-power superconducting electronic circuits. This work was supported by the U.S. DOE, Office of Science, Materials Sciences and Engineering Division, and Office of BES (contract DE-AC02-06CH11357). F. Colauto thanks the Sao Paulo Research Foundation FAPESP (Grant No. 2015/06.085-3).

  14. Thigh muscle activity, knee motion, and impact force during side-step pivoting in agility-trained female basketball players.

    Science.gov (United States)

    Wilderman, Danielle R; Ross, Scott E; Padua, Darin A

    2009-01-01

    Improving neuromuscular control of hamstrings muscles might have implications for decreasing anterior cruciate ligament injuries in females. To examine the effects of a 6-week agility training program on quadriceps and hamstrings muscle activation, knee flexion angles, and peak vertical ground reaction force. Prospective, randomized clinical research trial. Sports medicine research laboratory. Thirty female intramural basketball players with no history of knee injury (age = 21.07 +/- 2.82 years, height = 171.27 +/- 4.66 cm, mass = 66.36 +/- 7.41 kg). Participants were assigned to an agility training group or a control group that did not participate in agility training. Participants in the agility training group trained 4 times per week for 6 weeks. We used surface electromyography to assess muscle activation for the rectus femoris, vastus medialis oblique, medial hamstrings, and lateral hamstrings for 50 milliseconds before initial ground contact and while the foot was in contact with the ground during a side-step pivot maneuver. Knee flexion angles (at initial ground contact, maximum knee flexion, knee flexion displacement) and peak vertical ground reaction force also were assessed during this maneuver. Participants in the training group increased medial hamstrings activation during ground contact after the 6-week agility training program. Both groups decreased their vastus medialis oblique muscle activation during ground contact. Knee flexion angles and peak vertical ground reaction force did not change for either group. Agility training improved medial hamstrings activity in female intramural basketball players during a side-step pivot maneuver. Agility training that improves hamstrings activity might have implications for reducing anterior cruciate ligament sprain injury associated with side-step pivots.

  15. Generating energy dependent neutron flux maps for effective ...

    African Journals Online (AJOL)

    For activation analysis and irradiation scheme of miniature neutron source reactor, designers or engineers usually require information on thermal neutron flux levels and other energy group flux levels (such as fast, resonance and epithermal). A methodology for readily generating such flux maps and flux profiles for any ...

  16. Dynamo generation of magnetic fields in three-dimensional space: Solar cycle main flux tube formation and reversals

    International Nuclear Information System (INIS)

    Yoshimura, H.

    1983-01-01

    Dynamo processes as a magnetic field generation mechanism in astrophysics can be described essentially by movement and deformation of magnetic field lines due to plasma fluid motions. A basic element of the processes is a kinematic problem. As an important prototype of these processes, we investigate the case of the solar magnetic cycle. To follow the movement and deformation, we solve magnetohydrodynamic (MHD) equations by a numerical method with a prescribed velocity field. A simple combination of differential rotation and global convection, given by a linear analysis of fluid dynamics in a rotating sphere, can perpetually create and reverse great magnetic flux tubes encircling the Sun. We call them the main flux tubes of the solar cycle. They are progenitors of small-scale flux ropes of the solar activity. This shows that magnetic field generation by fluid motions is, in fact, possible and that MHD equations have a new type of oscillatory solution. The solar cycle can be identified with one of such oscillatory solutions. This means that we can follow detailed stages of the field generation and reversal processes of the dynamo by continuously observing the Sun. It is proposed that the magnetic flux tube formation by streaming plasma flows exemplified here could be a universal mechanism of flux tube formation in astrophysics

  17. Biomechanical Modeling, Simulation, and Comparison of Human Arm Motion to Mitigate Astronaut Task during Extra Vehicular Activity

    OpenAIRE

    B. Vadiraj; S. N. Omkar; B. Kapil Bharadwaj; Yash Vardhan Gupta

    2016-01-01

    During manned exploration of space, missions will require astronaut crewmembers to perform Extra Vehicular Activities (EVAs) for a variety of tasks. These EVAs take place after long periods of operations in space, and in and around unique vehicles, space structures and systems. Considering the remoteness and time spans in which these vehicles will operate, EVA system operations should utilize common worksites, tools and procedures as much as possible to increase the efficiency of training and...

  18. Women with fibromyalgia's experience with three motion-controlled video game consoles and indicators of symptom severity and performance of activities of daily living.

    Science.gov (United States)

    Mortensen, Jesper; Kristensen, Lola Qvist; Brooks, Eva Petersson; Brooks, Anthony Lewis

    2015-01-01

    Little is known of Motion-Controlled Video Games (MCVGs) as an intervention for people with chronic pain. The aim of this study was to explore the experience women with fibromyalgia syndrome (FMS) had, using commercially available MCVGs; and to investigate indicators of symptom severity and performance of activities of daily living (ADL). Of 15 female participants diagnosed with FMS, 7 completed a program of five sessions with Nintendo Wii (Wii), five sessions with PlayStation 3 Move (PS3 Move) and five sessions with Microsoft Xbox Kinect (Xbox Kinect). Interviews were conducted at baseline and post-intervention and were supported by data from observation and self-reported assessment. Participants experienced play with MCVGs as a way to get distraction from pain symptoms while doing fun and manageable exercise. They enjoyed the slow pace and familiarity of Wii, while some considered PS3 Move to be too fast paced. Xbox Kinect was reported as the best console for exercise. There were no indication of general improvement in symptom severity or performance of ADL. This study demonstrated MCVG as an effective healthcare intervention for the women with FMS who completed the program, with regards to temporary pain relief and enjoyable low impact exercise. Implications for Rehabilitation Exercise is recommended in the management of fibromyalgia syndrome (FMS). People with FMS often find it counterintuitive to exercise because of pain exacerbation, which may influence adherence to an exercise program. Motion-controlled video games may offer temporary pain relief and fun low impact exercise for women with FMS.

  19. Surface flux transport simulations: Effect of inflows toward active regions and random velocities on the evolution of the Sun's large-scale magnetic field

    Science.gov (United States)

    Martin-Belda, D.; Cameron, R. H.

    2016-02-01

    Aims: We aim to determine the effect of converging flows on the evolution of a bipolar magnetic region (BMR), and to investigate the role of these inflows in the generation of poloidal flux. We also discuss whether the flux dispersal due to turbulent flows can be described as a diffusion process. Methods: We developed a simple surface flux transport model based on point-like magnetic concentrations. We tracked the tilt angle, the magnetic flux and the axial dipole moment of a BMR in simulations with and without inflows and compared the results. To test the diffusion approximation, simulations of random walk dispersal of magnetic features were compared against the predictions of the diffusion treatment. Results: We confirm the validity of the diffusion approximation to describe flux dispersal on large scales. We find that the inflows enhance flux cancellation, but at the same time affect the latitudinal separation of the polarities of the bipolar region. In most cases the latitudinal separation is limited by the inflows, resulting in a reduction of the axial dipole moment of the BMR. However, when the initial tilt angle of the BMR is small, the inflows produce an increase in latitudinal separation that leads to an increase in the axial dipole moment in spite of the enhanced flux destruction. This can give rise to a tilt of the BMR even when the BMR was originally aligned parallel to the equator.

  20. D'' Layer Activation via Tidal Dissipation: A Link Between Non-Hydrostatic Ellipticity, Non-Chondritic Heat Flux, and Non-Plume Head Generation of Flood Basalts

    Science.gov (United States)

    Hager, B. H.; Mazarico, E.; Touma, J.; Wisdom, J.

    2003-12-01

    Quantitative understanding of Earth's heat budget has eluded a list of distinguished physicists and geochemists ranging from Lord Kelvin to Don L Anderson. The global heat flux is substantially greater than that generated by the estimated inventory of radioactive heat sources, so simple energy balance considerations demand an additional heat source. Secular cooling is commonly invoked to balance Earth's energy budget, but the required cooling rates are difficult to reconcile with both traditional convection calculations and petrologic estimates of ancient upper mantle temperatures. A non-geochemical heat source seems plausible. Indeed, Tuoma and Wisdom (Astron. J., 122, 2001) showed that tidal dissipation of rotational energy associated with resonant coupling could provide a substantial heat pulse to the CMB. D'' Layer Activation (DLA) by dumping of rotational energy could have important geodynamical consequences that we explore here. DLA could lead to a sudden (but modest) increase in the temperature of preexisting plumes, leading to a sudden increase in melt volume without the need for a troublesome plume head. The dissipation depends on non-hydrostatic CMB ellipticity, which itself is a result of mantle convection, leading to the possibility of an important feedback mechanism - DLA would lead to an increase in CMB ellipticity, further increasing the geodynamic importance of DLA.

  1. MotionFlow: Visual Abstraction and Aggregation of Sequential Patterns in Human Motion Tracking Data.

    Science.gov (United States)

    Jang, Sujin; Elmqvist, Niklas; Ramani, Karthik

    2016-01-01

    Pattern analysis of human motions, which is useful in many research areas, requires understanding and comparison of different styles of motion patterns. However, working with human motion tracking data to support such analysis poses great challenges. In this paper, we propose MotionFlow, a visual analytics system that provides an effective overview of various motion patterns based on an interactive flow visualization. This visualization formulates a motion sequence as transitions between static poses, and aggregates these sequences into a tree diagram to construct a set of motion patterns. The system also allows the users to directly reflect the context of data and their perception of pose similarities in generating representative pose states. We provide local and global controls over the partition-based clustering process. To support the users in organizing unstructured motion data into pattern groups, we designed a set of interactions that enables searching for similar motion sequences from the data, detailed exploration of data subsets, and creating and modifying the group of motion patterns. To evaluate the usability of MotionFlow, we conducted a user study with six researchers with expertise in gesture-based interaction design. They used MotionFlow to explore and organize unstructured motion tracking data. Results show that the researchers were able to easily learn how to use MotionFlow, and the system effectively supported their pattern analysis activities, including leveraging their perception and domain knowledge.

  2. Contribution of social isolation, restraint, and hindlimb unloading to changes in hemodynamic parameters and motion activity in rats.

    Directory of Open Access Journals (Sweden)

    Darya Tsvirkun

    Full Text Available The most accepted animal model for simulation of the physiological and morphological consequences of microgravity on the cardiovascular system is one of head-down hindlimb unloading. Experimental conditions surrounding this model include not only head-down tilting of rats, but also social and restraint stresses that have their own influences on cardiovascular system function. Here, we studied levels of spontaneous locomotor activity, blood pressure, and heart rate during 14 days under the following experimental conditions: cage control, social isolation in standard rat housing, social isolation in special cages for hindlimb unloading, horizontal attachment (restraint, and head-down hindlimb unloading. General activity and hemodynamic parameters were continuously monitored in conscious rats by telemetry. Heart rate and blood pressure were both evaluated during treadmill running to reveal cardiovascular deconditioning development as a result of unloading. The main findings of our work are that: social isolation and restraint induced persistent physical inactivity, while unloading in rats resulted in initial inactivity followed by normalization and increased locomotion after one week. Moreover, 14 days of hindlimb unloading showed significant elevation of blood pressure and slight elevation of heart rate. Hemodynamic changes in isolated and restrained rats largely reproduced the trends observed during unloading. Finally, we detected no augmentation of tachycardia during moderate exercise in rats after 14 days of unloading. Thus, we concluded that both social isolation and restraint, as an integral part of the model conditions, contribute essentially to cardiovascular reactions during head-down hindlimb unloading, compared to the little changes in the hydrostatic gradient.

  3. Motion in radiotherapy

    DEFF Research Database (Denmark)

    Korreman, Stine Sofia

    2012-01-01

    This review considers the management of motion in photon radiation therapy. An overview is given of magnitudes and variability of motion of various structures and organs, and how the motion affects images by producing artifacts and blurring. Imaging of motion is described, including 4DCT and 4DPE...

  4. SU-G-BRA-10: Marker Free Lung Tumor Motion Tracking by An Active Contour Model On Cone Beam CT Projections for Stereotactic Body Radiation Therapy of Lung Cancer

    International Nuclear Information System (INIS)

    Chao, M; Yuan, Y; Lo, Y; Wei, J

    2016-01-01

    Purpose: To develop a novel strategy to extract the lung tumor motion from cone beam CT (CBCT) projections by an active contour model with interpolated respiration learned from diaphragm motion. Methods: Tumor tracking on CBCT projections was accomplished with the templates derived from planning CT (pCT). There are three major steps in the proposed algorithm: 1) The pCT was modified to form two CT sets: a tumor removed pCT and a tumor only pCT, the respective digitally reconstructed radiographs DRRtr and DRRto following the same geometry of the CBCT projections were generated correspondingly. 2) The DRRtr was rigidly registered with the CBCT projections on the frame-by-frame basis. Difference images between CBCT projections and the registered DRRtr were generated where the tumor visibility was appreciably enhanced. 3) An active contour method was applied to track the tumor motion on the tumor enhanced projections with DRRto as templates to initialize the tumor tracking while the respiratory motion was compensated for by interpolating the diaphragm motion estimated by our novel constrained linear regression approach. CBCT and pCT from five patients undergoing stereotactic body radiotherapy were included in addition to scans from a Quasar phantom programmed with known motion. Manual tumor tracking was performed on CBCT projections and was compared to the automatic tracking to evaluate the algorithm accuracy. Results: The phantom study showed that the error between the automatic tracking and the ground truth was within 0.2mm. For the patients the discrepancy between the calculation and the manual tracking was between 1.4 and 2.2 mm depending on the location and shape of the lung tumor. Similar patterns were observed in the frequency domain. Conclusion: The new algorithm demonstrated the feasibility to track the lung tumor from noisy CBCT projections, providing a potential solution to better motion management for lung radiation therapy.

  5. SU-G-BRA-10: Marker Free Lung Tumor Motion Tracking by An Active Contour Model On Cone Beam CT Projections for Stereotactic Body Radiation Therapy of Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chao, M; Yuan, Y; Lo, Y [The Mount Sinai Medical Center, New York, NY (United States); Wei, J [City College of New York, New York, NY (United States)

    2016-06-15

    Purpose: To develop a novel strategy to extract the lung tumor motion from cone beam CT (CBCT) projections by an active contour model with interpolated respiration learned from diaphragm motion. Methods: Tumor tracking on CBCT projections was accomplished with the templates derived from planning CT (pCT). There are three major steps in the proposed algorithm: 1) The pCT was modified to form two CT sets: a tumor removed pCT and a tumor only pCT, the respective digitally reconstructed radiographs DRRtr and DRRto following the same geometry of the CBCT projections were generated correspondingly. 2) The DRRtr was rigidly registered with the CBCT projections on the frame-by-frame basis. Difference images between CBCT projections and the registered DRRtr were generated where the tumor visibility was appreciably enhanced. 3) An active contour method was applied to track the tumor motion on the tumor enhanced projections with DRRto as templates to initialize the tumor tracking while the respiratory motion was compensated for by interpolating the diaphragm motion estimated by our novel constrained linear regression approach. CBCT and pCT from five patients undergoing stereotactic body radiotherapy were included in addition to scans from a Quasar phantom programmed with known motion. Manual tumor tracking was performed on CBCT projections and was compared to the automatic tracking to evaluate the algorithm accuracy. Results: The phantom study showed that the error between the automatic tracking and the ground truth was within 0.2mm. For the patients the discrepancy between the calculation and the manual tracking was between 1.4 and 2.2 mm depending on the location and shape of the lung tumor. Similar patterns were observed in the frequency domain. Conclusion: The new algorithm demonstrated the feasibility to track the lung tumor from noisy CBCT projections, providing a potential solution to better motion management for lung radiation therapy.

  6. Use of Germanium as comparator and integral monitor of neutron flux in activation analysis; Utilizacion del germanio como comparador y monitor integral de flujo neutronico en analisis por activacion

    Energy Technology Data Exchange (ETDEWEB)

    Furnari, Juan C.; Cohen, Isaac M. [Comision Nacional de Energia Atomica, Buenos Aires (Argentina). Centro Atomico Ezeiza; Arribere, Maria A.; Kestelman, Abraham J. [Comision Nacional de Energia Atomica, San Carlos de Bariloche (Argentina). Centro Atomico Bariloche

    1997-10-01

    The possibility of using germanium as monitor of the thermal and epithermal components of the neutron flux, and comparator in parametric activation analysis, is discussed. The advantages and drawbacks associated to the use of this element are commented on, and the comparison with zirconium, in terms of the determination relative error, is performed. The utilisation of germanium as integral flux monitor, including the fast component of the neutron spectrum, is also discussed. Data corresponding to measurements of k{sub 0} factor for the most relevant gamma transitions from Ge-75 and Be-77 are presented, as well as the results of the reference material analysis, employing germanium as flux monitor and comparator in a simultaneous way. (author). 8 refs., 3 figs., 2 tabs.

  7. Motion Capturing Emotions

    OpenAIRE

    Wood Karen; Cisneros Rosemary E.; Whatley Sarah

    2017-01-01

    The paper explores the activities conducted as part of WhoLoDancE: Whole Body Interaction Learning for Dance Education which is an EU-funded Horizon 2020 project. In particular, we discuss the motion capture sessions that took place at Motek, Amsterdam as well as the dancers’ experience of being captured and watching themselves or others as varying visual representations through the HoloLens. HoloLens is Microsoft’s first holographic computer that you wear as you would a pair of glasses. The ...

  8. Patellofemoral joint motion

    International Nuclear Information System (INIS)

    Stanford, W.; Phelan, J.; Albright, J.; Kathol, M.; Rooholamini, S.A.; El-Khoury, G.Y.; Palutsis, G.R.

    1988-01-01

    This paper describes the use of ultrafast computed tomography (CT) to obtain dynamic images of the patellofemoral joint during active motion. Thirty-eight patients underwent measurements of tangent offset, bisect offset, congruence angle, patellar tilt angle, lateral patellofemoral angle, sulcus angle, and sulcus depth made during leg movement. Selected parameters were compared with Merchant views. Significant correlations were obtained between Merchant views and comparable ultrafast CT views for all parameters except sulcus angle. Correlations between the other parameters were poor. Cine strips showed two patterns of movement; the patella remained centered either throughout excursion or until the last 20 0 of full extension, when it would sublux laterally

  9. Motion Transplantation Techniques: A Survey

    NARCIS (Netherlands)

    van Basten, Ben; Egges, Arjan

    2012-01-01

    During the past decade, researchers have developed several techniques for transplanting motions. These techniques transplant a partial auxiliary motion, possibly defined for a small set of degrees of freedom, on a base motion. Motion transplantation improves motion databases' expressiveness and

  10. Does Early Versus Delayed Active Range of Motion Affect Rotator Cuff Healing After Surgical Repair? A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Kluczynski, Melissa A; Isenburg, Maureen M; Marzo, John M; Bisson, Leslie J

    2016-03-01

    The timing of passive range of motion (ROM) after surgical repair of the rotator cuff (RC) has been shown to affect healing. However, it is unknown if early or delayed active ROM affects healing. To determine whether early versus delayed active ROM affects structural results of RC repair surgery. Systematic review and meta-analysis. A systematic review of articles published between January 2004 and April 2014 was conducted. Structural results were compared for early (repair method. A total of 37 studies (2251 repairs) were included in the analysis, with 10 (649 repairs) in the early group and 27 (1602 repairs) in the delayed group. For tears ≤3 cm, the risk of a structural tendon defect was higher in the early versus delayed group for transosseous plus single-row suture anchor repairs (39.7% vs 24.3%; RR, 1.63 [95% CI, 1.28-2.08]). For tears >3 cm, the risk of a structural tendon defect was higher in the early versus delayed group for suture bridge repairs (48% vs 17.5%; RR, 2.74 [95% CI, 1.59-4.73]) and all repair methods combined (40.5% vs 26.7%; RR, 1.52 [95% CI, 1.17-1.97]). For tears >5 cm, the risk of structural tendon defect was higher in the early versus delayed group for suture bridge repairs (100% vs 16.7%; RR, 6.00 [95% CI, 1.69-21.26]). There were no statistically significant associations for tears measuring ≤1, 1-3, or 3-5 cm. Early active ROM was associated with increased risk of a structural defect for small and large RC tears, and thus might not be advisable after RC repair. © 2015 The Author(s).

  11. High heat flux facility GLADIS

    International Nuclear Information System (INIS)

    Greuner, H.; Boeswirth, B.; Boscary, J.; McNeely, P.

    2007-01-01

    The new ion beam facility GLADIS started the operation at IPP Garching. The facility is equipped with two individual 1.1 MW power ion sources for testing actively cooled plasma facing components under high heat fluxes. Each ion source generates heat loads between 3 and 55 MW/m 2 with a beam diameter of 70 mm at the target position. These parameters allow effective testing from probes to large components up to 2 m length. The high heat flux allows the target to be installed inclined to the beam and thus increases the heated surface length up to 200 mm for a heat flux of 15 MW/m 2 in the standard operating regime. Thus the facility has the potential capability for testing of full scale ITER divertor targets. Heat load tests on the WENDELSTEIN 7-X pre-series divertor targets have been successfully started. These tests will validate the design and manufacturing for the production of 950 elements

  12. Flux lattice commensurability and the resistive transition of wire networks

    International Nuclear Information System (INIS)

    Wilks, C.W.

    1992-01-01

    The commensurability of one structure with one length scale with that of another with a different length scale is a familiar problem. For a superconducting wire network in a magnetic field the two competing length scales are that of the network and that of the magnetic flux lattice. The superconducting to normal state phase boundary, Tc(H), of a periodic network shows periodic oscillations with a period of H 0 = Φ 0 /A where Φ 0 = hc/2e and A is the area of the elementary tile. These oscillations are due to flux quantization around the individual tiles of the network. In addition, within each period, there is structure at H = (p/q)H 0 (p,q integers) which is due to the vortices forming energetically favorable commensurate arrangements on top of the underlying lattice. The authors have studied the broadening of the zero field resistive transition with the application of a magnetic field for networks of various geometries. This was done by either directly measuring the resistive transitions at the commensurate fields or by using a technique that utilizes phase boundary measurements and yields the field induced width of the resistive transition as a continued function of the field. There is a striking dependence of the field induced width on whether or not the field is commensurate with the network. The broadening at the commensurate flux filling is well described by thermally activated vortex motion using the formalism of Ambegoakar and Halperin which allows us to extract numbers for the pinning potentials at the various commensurate states. The authors have found that the size of the discontinuity in the slope of the phase boundary at a commensurate filling is related to the strength of the lattice and therefore to the broadening of the transition at that filling so that by just looking at the phase boundary of a network one can gauge the relative broadening of the resistive transitions at the commensurate flux fillings

  13. Monitoring core barrel motion by neutron noise diagnostics

    International Nuclear Information System (INIS)

    Por, G.

    1985-08-01

    The core barrel motion is detected by ionization chambers located around the reactor vessel. The method is based on the measurement of the neutron flux fluctuations. Calculations to determine the direction and the size of the motion are discussed. The identification of core barrel motion and its connection with the error of one of the main circulating pumps in the Rheinsberg nuclear power plant are described. Core barrel motion of 10 Hz with an amplitude less than 50 μm could be diagnozed at the Paks-1 reactor using the Dutch high accuracy evaluation system. (V.N.)

  14. Investigation of wire motion in superconducting magnets

    International Nuclear Information System (INIS)

    Ogitsu, T.; Tsuchiya, K.; Devred, A.

    1990-09-01

    The large Lorentz forces occuring during the excitation of superconducting magnets can provoke sudden motions of wire, which eventually release enough energy to trigger a quench. These wire motions are accompanied by two electromagnetic effects: an induced emf along the moved wire, and a local change in flux caused by the minute dislocation of current. Both effects cause spikes in the coil voltage. Voltage data recorded during the excitation of a superconducting quadrupole magnet which early exhibit such events are here reported. Interpretations of the voltage spikes in terms of energy release are also presented, leading to insights on the spectrum of the disturbances which occur in real magnets. 15 refs

  15. Dynamics of warped flux compactifications

    International Nuclear Information System (INIS)

    Shiu, Gary; Underwood, Bret; Torroba, Gonzalo; Douglas, Michael R.

    2008-01-01

    We discuss the four dimensional effective action for type IIB flux compactifications, and obtain the quadratic terms taking warp effects into account. The analysis includes both the 4-d zero modes and their KK excitations, which become light at large warping. We identify an 'axial' type gauge for the supergravity fluctuations, which makes the four dimensional degrees of freedom manifest. The other key ingredient is the existence of constraints coming from the ten dimensional equations of motion. Applying these conditions leads to considerable simplifications, enabling us to obtain the low energy lagrangian explicitly. In particular, the warped Kaehler potential for metric moduli is computed and it is shown that there are no mixings with the KK fluctuations and the result differs from previous proposals. The four dimensional potential contains a generalization of the Gukov-Vafa-Witten term, plus usual mass terms for KK modes.

  16. Sun's pole-equator flux differences

    Energy Technology Data Exchange (ETDEWEB)

    Belvedere, G [Istituto di Astronomia dell' Universita di Catania, Italy; Paterno, L [Osservatorio Astrofisico di Catania, Italy

    1977-04-01

    The possibility that large flux differences between the poles and the equator at the bottom of the solar convective zone are compatible with the small differences observed at the surface is studied. The consequences of increasing the depth of the convective zone due to overshooting are explored. A Boussinesq model is used for the convective zone and it is assumed that the interaction of the global convection with rotation is modelled through a convective flux coefficient whose perturbed part is proportional to the local Taylor number. The numerical integration of the equations of motion and energy shows that coexistence between large pole-equator flux differences at the bottom and small ones at the surface is possible if the solar convective zone extends to a depth of 0.4 R(Sun). The angular velocity distribution inside the convective zone is in agreement with the ..cap alpha omega..-dynamo theories of the solar cycle.

  17. Robot motion control in mobile environment

    Institute of Scientific and Technical Information of China (English)

    Iliya V Miroshnik; HUANG Xian-lin(黄显林); HE Jie(贺杰)

    2003-01-01

    With the problem of robot motion control in dynamic environment represented by mobile obstacles,working pieces and external mechanisms considered, a relevant control actions design procedure has been pro-posed to provide coordination of robot motions with respect to the moving external objects so that an extension ofrobot spatial motion techniques and active robotic strategies based on approaches of nonlinear control theory canbe achieved.

  18. STABILITY OF MOTION OF MOBILE MODULE OF EXPERIMENTAL SETUP IN THE STUDY OF ACTIVE ROTARY WORKING OF MACHINES FOR SOIL TREATMENT

    Directory of Open Access Journals (Sweden)

    Vladimir F. Kupryashkin

    2016-06-01

    Full Text Available Introduction. The paper is devoted to the theoretical study of stability of movement of the movable unit of the experimental setup intended for the exploration of the active rotational working organs of the car for soil treatment. This takes into account the design features of the mobile unit and features active rotary force interaction of working bodies with the soil. From the analysis of previously conducted both theoretical and experimental studies of this type of working bodies noted the possibility of breaking the stability of the mobile stroke unit, which in turn will have a negative impact on the enforcement of a given method of the experiment program. From the analysis of previous studies shows that the assumptions under which they were made, not allow you to fully take into account the nature of the effect occurring dynamic processes of interaction of active rotary working bodies with the soil on the experimental setup truck driving stability. Materials and Methods. To address the shortcomings in the research, based on a synthesis of the main provisions and laws of mechanics and the experimental data of active rotary force interaction of working bodies with the soil, carried out theoretical studies of stability of movement of the movable unit of the experimental setup in view of its design features and conditions of the experiment. Results. A theoretical study was composed of loading trolley design scheme of the experimental setup with regard to its design features and power factors acting on its working elements, namely, the wheel bearing and studied active rotary working bodies. Processing results of the study allowed the weary twist zone of stable and unstable movement of the movable unit Expo tal installation. The presence of unstable movement zone carts at-leads to a breach of the conditions set by the plan of experimental-governmental research and a negative impact on their quality and purity. Discussion and Conclusions. All of

  19. Attitude Motion of Cylindrical Space Debris during Its Removal by Ion Beam

    Directory of Open Access Journals (Sweden)

    Vladimir S. Aslanov

    2017-01-01

    Full Text Available The paper is devoted to the problem of space debris mitigation. Contactless method of the space debris deorbiting is considered. It is assumed that ion thrusters on the active spacecraft create the ion flow, which blows the debris and slows it down. The objectives of this work are the development of mathematical models and the research of space debris motion under the action of the ion flow. It is supposed that the space debris is a rigid body of a cylindrical shape. Calculation of ion beam force and torque was performed for a self-similar model of plasma plume expansion using the hypothesis of ion fully diffused reflection from a surface. A mathematical model describing plane motions of the cylindrical space debris under the influence of gravity gradient torque and the ion flux was constructed. It was shown that motion of the space debris around its center of mass has a significant effect on its removal time. Phase portraits, describing the motion of the space debris relative to its center of mass, were constructed. Comparison of the descent times in different motion modes was carried out. The results can be used to create new effective systems of large space debris removal.

  20. Attention and apparent motion.

    Science.gov (United States)

    Horowitz, T; Treisman, A

    1994-01-01

    Two dissociations between short- and long-range motion in visual search are reported. Previous research has shown parallel processing for short-range motion and apparently serial processing for long-range motion. This finding has been replicated and it has also been found that search for short-range targets can be impaired both by using bicontrast stimuli, and by prior adaptation to the target direction of motion. Neither factor impaired search in long-range motion displays. Adaptation actually facilitated search with long-range displays, which is attributed to response-level effects. A feature-integration account of apparent motion is proposed. In this theory, short-range motion depends on specialized motion feature detectors operating in parallel across the display, but subject to selective adaptation, whereas attention is needed to link successive elements when they appear at greater separations, or across opposite contrasts.

  1. OpenFLUX: efficient modelling software for 13C-based metabolic flux analysis

    Directory of Open Access Journals (Sweden)

    Nielsen Lars K

    2009-05-01

    Full Text Available Abstract Background The quantitative analysis of metabolic fluxes, i.e., in vivo activities of intracellular enzymes and pathways, provides key information on biological systems in systems biology and metabolic engineering. It is based on a comprehensive approach combining (i tracer cultivation on 13C substrates, (ii 13C labelling analysis by mass spectrometry and (iii mathematical modelling for experimental design, data processing, flux calculation and statistics. Whereas the cultivation and the analytical part is fairly advanced, a lack of appropriate modelling software solutions for all modelling aspects in flux studies is limiting the application of metabolic flux analysis. Results We have developed OpenFLUX as a user friendly, yet flexible software application for small and large scale 13C metabolic flux analysis. The application is based on the new Elementary Metabolite Unit (EMU framework, significantly enhancing computation speed for flux calculation. From simple notation of metabolic reaction networks defined in a spreadsheet, the OpenFLUX parser automatically generates MATLAB-readable metabolite and isotopomer balances, thus strongly facilitating model creation. The model can be used to perform experimental design, parameter estimation and sensitivity analysis either using the built-in gradient-based search or Monte Carlo algorithms or in user-defined algorithms. Exemplified for a microbial flux study with 71 reactions, 8 free flux parameters and mass isotopomer distribution of 10 metabolites, OpenFLUX allowed to automatically compile the EMU-based model from an Excel file containing metabolic reactions and carbon transfer mechanisms, showing it's user-friendliness. It reliably reproduced the published data and optimum flux distributions for the network under study were found quickly ( Conclusion We have developed a fast, accurate application to perform steady-state 13C metabolic flux analysis. OpenFLUX will strongly facilitate and

  2. Characteristics of heat flux and particle flux to the divertor in H-mode of JT-60U

    International Nuclear Information System (INIS)

    Itami, K.; Hosogane, N.; Asakura, N.; Kubo, H.; Tsuji, S.; Shimada, M.

    1995-01-01

    Heat flux and particle flux behavior in H-mode is studied in a comparative manner. It was confirmed that the multiple peak structure of heat flux during ELM activity has a role in reducing the average value of a peak heat flux at the divertor. In order to characterize heat and particle flux during ELM activity, the ELM part and the steady state part of heat flux and particle flux were determined and statistically analyzed. A large in-out asymmetry of peak ELM heat flux density was found. The asymmetry is almost unaffected by the ion grad-B drift direction. In-out asymmetry of both ELM and steady-state parts of the particle flux were found to be similar. ((orig.))

  3. Determination of nitrogen in wheat flour through Activation analysis using Fast neutron flux of a Thermal nuclear reactor; Determinacion de nitrogeno en harina de trigo mediante analisis por activacion empleando el flujo de neutrones rapidos de un reactor nuclear termico

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez G, T

    1976-07-01

    In this work is done a technical study for determining Nitrogen (protein) and other elements in wheat flour Activation analysis, with Fast neutrons from a Thermal nuclear reactor. Initially it is given an introduction about the basic principles of the methods of analysis. Equipment used in Activation analysis and a brief description of the neutron source (Thermal nuclear reactor). The realized experiments for determining the flux form in the irradiation site, the half life of N-13 and the interferences due to the sample composition are included too. Finally, the obtained results by Activation and the Kjeldahl method are tabulated. (Author)

  4. Compact neutron flux monitor

    International Nuclear Information System (INIS)

    Madhavi, V.; Phatak, P.R.; Bahadur, C.; Bayala, A.K.; Jakati, R.K.; Sathian, V.

    2003-01-01

    Full text: A compact size neutron flux monitor has been developed incorporating standard boards developed for smart radiation monitors. The sensitivity of the monitors is 0.4cps/nV. It has been tested up to 2075 nV flux with standard neutron sources. It shows convincing results even in high flux areas like 6m away from the accelerator in RMC (Parel) for 106/107 nV. These monitors have a focal and remote display, alarm function with potential free contacts for centralized control and additional provision of connectivity via RS485/Ethernet. This paper describes the construction, working and results of the above flux monitor

  5. Objects in Motion

    Science.gov (United States)

    Damonte, Kathleen

    2004-01-01

    One thing scientists study is how objects move. A famous scientist named Sir Isaac Newton (1642-1727) spent a lot of time observing objects in motion and came up with three laws that describe how things move. This explanation only deals with the first of his three laws of motion. Newton's First Law of Motion says that moving objects will continue…

  6. Motion compensated digital tomosynthesis

    NARCIS (Netherlands)

    van der Reijden, Anneke; van Herk, Marcel; Sonke, Jan-Jakob

    2013-01-01

    Digital tomosynthesis (DTS) is a limited angle image reconstruction method for cone beam projections that offers patient surveillance capabilities during VMAT based SBRT delivery. Motion compensation (MC) has the potential to mitigate motion artifacts caused by respiratory motion, such as blur. The

  7. Kinesthetic information disambiguates visual motion signals.

    Science.gov (United States)

    Hu, Bo; Knill, David C

    2010-05-25

    Numerous studies have shown that extra-retinal signals can disambiguate motion information created by movements of the eye or head. We report a new form of cross-modal sensory integration in which the kinesthetic information generated by active hand movements essentially captures ambiguous visual motion information. Several previous studies have shown that active movement can bias observers' percepts of bi-stable stimuli; however, these effects seem to be best explained by attentional mechanisms. We show that kinesthetic information can change an otherwise stable perception of motion, providing evidence of genuine fusion between visual and kinesthetic information. The experiments take advantage of the aperture problem, in which the motion of a one-dimensional grating pattern behind an aperture, while geometrically ambiguous, appears to move stably in the grating normal direction. When actively moving the pattern, however, the observer sees the motion to be in the hand movement direction. Copyright 2010 Elsevier Ltd. All rights reserved.

  8. Mass motions in a quiescent filament

    International Nuclear Information System (INIS)

    Malherbe, J.M.; Mein, P.; Schmieder, B.

    1982-01-01

    Observations are presented of the sudden disappearance of a filament (N2O, E35) above an active region with the Multichannel Substractive Double Pass Spectrograph operating on the Meudon Solar Tower, France, from 10:45 UT to 13:30 UT on June 22, 1981. Measurements of the velocity fields and intensity fluctuations were obtained. It was found that the sudden disappearance did not take place simultaneously in all parts of the filament: thin threads with upward radial velocities reaching about 50 km/s were successively observed inside the prominence from the south to north regions. It is suggested that these motions corresponded to the rise of material along magnetic loops closely related to the prominence structure. An investigation of the dynamics inside such a magnetic loop shows a strongly accelerated high speed flow and a deformation of the flux tube, probably due to the centrifugal forces exerted by the flow on the magnetic lines. In addition, it is shown that the present theoretical models cannot account for the prominence structure as a cold H-alpha loop system and the acceleration process of material inside such loops

  9. On the higher order derivatives in the laws of motion and their application to an active force generator and to condition monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Lahdelma, S.

    1995-12-31

    The current paper commences with a review of the history of classical mechanics. The problems connected with condition monitoring and the construction of high-speed machines are so difficult that a knowledge of the fundamentals of mechanics is essential for solving them. It is thus natural that careful attention should be paid to the starting points and assumptions upon which earlier measurement and calculation methods have relied, for it is only after this than one can deduce whether certain simplifications are due to inadequate measurement technology, inflexibility of ideas, a level of precision that is restricted to simple applications or efforts towards simple models merely in order to avoid calculation work. The historical section contains citations from the original sources, which will be useful for those wishing to examine the topic in more detail. The actual textual part is written in such a way that the fundamental content of the works quoted becomes clear even though not all the individual points are translated word for word. The general practice of utilizing the original notations is observed in this section. The paper contains a new way of deriving the laws of motion in classical mechanics from the fundamental law presented in Section 3. Original sources are employed in interpretations regarding terminology, particularly in the case of Lagrange`s function and Hamilton`s principle. The experimental section involves an examination of a two-particle system composed of an active force generator controlled by the first and second time derivatives of the accelerations and by the fractional time derivatives of the particles. This also enables resonance vibrations to be reduced considerably and highly stable solutions to be found

  10. PERFORMANCE OF HIGH SCHOOL FOOTBALL PLAYERS ON CLINICAL MEASURES OF DEEP CERVICAL FLEXOR ENDURANCE AND CERVICAL ACTIVE RANGE OF MOTION: IS HISTORY OF CONCUSSION A FACTOR?

    Science.gov (United States)

    Smith, Laura; Ruediger, Thomas; Alsalaheen, Bara; Bean, Ryan

    2016-04-01

    More than one million adolescent athletes participated in organized high school sanctioned football during the 2014-15 season. These athletes are at risk for sustaining concussion. Although cervical spine active range of motion (AROM) and deep neck flexor endurance may serve a preventative role in concussion, and widespread clinical use of measurements of these variables, reference values are not available for this population. Cost effective, clinically relevant methods for measuring neck endurance are also well established for adolescent athletes. The purpose of this study was to report reference values for deep cervical flexor endurance and cervical AROM in adolescent football players and examine whether differences in these measures exist in high school football players with and without a history of concussion. Concussion history, cervical AROM, and deep neck flexor endurance were measured in 122 high school football players. Reference values were calculated for AROM and endurance measures; association were examined between various descriptive variables and concussion. No statistically significant differences were found between athletes with a history of concussion and those without. A modest inverse correlation was seen between body mass and AROM in the sagittal and transverse planes. The results of this study indicate that the participants with larger body mass had less cervical AROM in some directions. While cervical AROM and endurance measurements may not be adequate to identify adolescents with a history of previous concussions among high school football players. However, if a concussion is sustained, these measures can offer a baseline to examine whether cervical AROM is affected as compared to healthy adolescents. 2c.

  11. Mass motions in impulsive flarelike brightenings as observed by OSO 8

    International Nuclear Information System (INIS)

    Bruner, E.C. Jr.; Lites, B.W.

    1979-01-01

    CIV lambda1548 line profiles obtained with the University of Colorado spectrometer aboard OSO 8 reveal transient, redshifted brightenings in the chromosphere-corona transition region above active regions and sunspots. In these events the intensity rises by factors of up to 5 in less than the profile sampling interval of 27 s. These events indicate that the emitting material is moving downward at velocities of up to 30 km s -1 . The increase in line intensity and the amount of motion are consistent with the interpretation of these events as pressure waves propagating down magnetic flux loops

  12. Mass motions in impulsive flarelike brightenings as observed by OSO 8. [mechanism response for solar flares

    Science.gov (United States)

    Bruner, E. C., Jr.; Lites, B. W.

    1979-01-01

    C IV 1548-A line profiles obtained with the University of Colorado spectrometer aboard OSO 8 reveal transient, redshifted brightenings in the chromosphere-corona transition region above active regions and sunspots. In these events the intensity rises by factors of up to 5 in less than the profile sampling interval of 27 sec. These events indicate that the emitting material is moving downward at velocities of up to 30 km/sec. The increase in line intensity and the amount of motion are consistent with the interpretation of these events as pressure waves propagating down magnetic flux loops.

  13. Rolling Shutter Motion Deblurring

    KAUST Repository

    Su, Shuochen

    2015-06-07

    Although motion blur and rolling shutter deformations are closely coupled artifacts in images taken with CMOS image sensors, the two phenomena have so far mostly been treated separately, with deblurring algorithms being unable to handle rolling shutter wobble, and rolling shutter algorithms being incapable of dealing with motion blur. We propose an approach that delivers sharp and undis torted output given a single rolling shutter motion blurred image. The key to achieving this is a global modeling of the camera motion trajectory, which enables each scanline of the image to be deblurred with the corresponding motion segment. We show the results of the proposed framework through experiments on synthetic and real data.

  14. Smoothing Motion Estimates for Radar Motion Compensation.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-07-01

    Simple motion models for complex motion environments are often not adequate for keeping radar data coherent. Eve n perfect motion samples appli ed to imperfect models may lead to interim calculations e xhibiting errors that lead to degraded processing results. Herein we discuss a specific i ssue involving calculating motion for groups of pulses, with measurements only available at pulse-group boundaries. - 4 - Acknowledgements This report was funded by General A tomics Aeronautical Systems, Inc. (GA-ASI) Mission Systems under Cooperative Re search and Development Agre ement (CRADA) SC08/01749 between Sandia National Laboratories and GA-ASI. General Atomics Aeronautical Systems, Inc. (GA-ASI), an affilia te of privately-held General Atomics, is a leading manufacturer of Remotely Piloted Aircraft (RPA) systems, radars, and electro-optic and rel ated mission systems, includin g the Predator(r)/Gray Eagle(r)-series and Lynx(r) Multi-mode Radar.

  15. Curves from Motion, Motion from Curves

    Science.gov (United States)

    2000-01-01

    De linearum curvarum cum lineis rectis comparatione dissertatio geometrica - an appendix to a treatise by de Lalouv~re (this was the only publication... correct solution to the problem of motion in the gravity of a permeable rotating Earth, considered by Torricelli (see §3). If the Earth is a homogeneous...in 1686, which contains the correct solution as part of a remarkably comprehensive theory of orbital motions under centripetal forces. It is a

  16. Primary cosmic ray flux

    Energy Technology Data Exchange (ETDEWEB)

    Stanev, Todor

    2001-05-01

    We discuss the primary cosmic ray flux from the point of view of particle interactions and production of atmospheric neutrinos. The overall normalization of the cosmic ray flux and its time variations and site dependence are major ingredients of the atmospheric neutrino predictions and the basis for the derivation of the neutrino oscillation parameters.

  17. Flux cutting in superconductors

    International Nuclear Information System (INIS)

    Campbell, A M

    2011-01-01

    This paper describes experiments and theories of flux cutting in superconductors. The use of the flux line picture in free space is discussed. In superconductors cutting can either be by means of flux at an angle to other layers of flux, as in longitudinal current experiments, or due to shearing of the vortex lattice as in grain boundaries in YBCO. Experiments on longitudinal currents can be interpreted in terms of flux rings penetrating axial lines. More physical models of flux cutting are discussed but all predict much larger flux cutting forces than are observed. Also, cutting is occurring at angles between vortices of about one millidegree which is hard to explain. The double critical state model and its developments are discussed in relation to experiments on crossed and rotating fields. A new experiment suggested by Clem gives more direct information. It shows that an elliptical yield surface of the critical state works well, but none of the theoretical proposals for determining the direction of E are universally applicable. It appears that, as soon as any flux flow takes place, cutting also occurs. The conclusion is that new theories are required. (perspective)

  18. Structural motion engineering

    CERN Document Server

    Connor, Jerome

    2014-01-01

    This innovative volume provides a systematic treatment of the basic concepts and computational procedures for structural motion design and engineering for civil installations. The authors illustrate the application of motion control to a wide spectrum of buildings through many examples. Topics covered include optimal stiffness distributions for building-type structures, the role of damping in controlling motion, tuned mass dampers, base isolation systems, linear control, and nonlinear control. The book's primary objective is the satisfaction of motion-related design requirements, such as restrictions on displacement and acceleration. The book is ideal for practicing engineers and graduate students. This book also: ·         Broadens practitioners' understanding of structural motion control, the enabling technology for motion-based design ·         Provides readers the tools to satisfy requirements of modern, ultra-high strength materials that lack corresponding stiffness, where the motion re...

  19. Nanoparticle mediated micromotor motion

    Science.gov (United States)

    Liu, Mei; Liu, Limei; Gao, Wenlong; Su, Miaoda; Ge, Ya; Shi, Lili; Zhang, Hui; Dong, Bin; Li, Christopher Y.

    2015-03-01

    In this paper, we report the utilization of nanoparticles to mediate the motion of a polymer single crystal catalytic micromotor. Micromotors have been fabricated by directly self-assembling functional nanoparticles (platinum and iron oxide nanoparticles) onto one or both sides of two-dimensional polymer single crystals. We show that the moving velocity of these micromotors in fluids can be readily tuned by controlling the nanoparticles' surface wettability and catalytic activity. A 3 times velocity increase has been achieved for a hydrophobic micromotor as opposed to the hydrophilic ones. Furthermore, we demonstrate that the catalytic activity of platinum nanoparticles inside the micromotor can be enhanced by their synergetic interactions with iron oxide nanoparticles and an electric field. Both strategies lead to dramatically increased moving velocities, with the highest value reaching ~200 μm s-1. By decreasing the nanoparticles' surface wettability and increasing their catalytic activity, a maximum of a ~10-fold increase in the moving speed of the nanoparticle based micromotor can be achieved. Our results demonstrate the advantages of using nanoparticles in micromotor systems.In this paper, we report the utilization of nanoparticles to mediate the motion of a polymer single crystal catalytic micromotor. Micromotors have been fabricated by directly self-assembling functional nanoparticles (platinum and iron oxide nanoparticles) onto one or both sides of two-dimensional polymer single crystals. We show that the moving velocity of these micromotors in fluids can be readily tuned by controlling the nanoparticles' surface wettability and catalytic activity. A 3 times velocity increase has been achieved for a hydrophobic micromotor as opposed to the hydrophilic ones. Furthermore, we demonstrate that the catalytic activity of platinum nanoparticles inside the micromotor can be enhanced by their synergetic interactions with iron oxide nanoparticles and an electric

  20. Measure of thermal neutron flux in the IPEN/MB-01 reactor using {sup 197} Au wire activation detectors; Medida do fluxo de neutrons termicos do reator IPEN/MB-01 com detectores de ativacao de fios de {sup 197} Au

    Energy Technology Data Exchange (ETDEWEB)

    Marques, Andre Luis Ferreira

    1995-12-31

    This dissertation has aimed at developing a neutron flux measurement technique by means of detectors activation analysis. The main task of this work was the implementation of this thermal neutron flux measurement technique, using gold wires as activation detectors in the IPEN/MB-01 reactor core. The neutron thermal flux spatial distribution was obtained by gold wire activation technique, with wire diameters of 0.125 mm and 0.250 mm in seven selected reactor experimental channels. The values of thermal flux were about 10{sup 9} neutrons/cm{sup 2}.s. This experiment has been the first one conducted with gold wires in the IPEN/MB-01 reactor, being this technique implemented for use by experiments in flux mapping of the core 73 refs., 60 figs., 31 tabs.

  1. Measure of thermal neutron flux in the IPEN/MB-01 reactor using {sup 197} Au wire activation detectors; Medida do fluxo de neutrons termicos do reator IPEN/MB-01 com detectores de ativacao de fios de {sup 197} Au

    Energy Technology Data Exchange (ETDEWEB)

    Marques, Andre Luis Ferreira

    1996-12-31

    This dissertation has aimed at developing a neutron flux measurement technique by means of detectors activation analysis. The main task of this work was the implementation of this thermal neutron flux measurement technique, using gold wires as activation detectors in the IPEN/MB-01 reactor core. The neutron thermal flux spatial distribution was obtained by gold wire activation technique, with wire diameters of 0.125 mm and 0.250 mm in seven selected reactor experimental channels. The values of thermal flux were about 10{sup 9} neutrons/cm{sup 2}.s. This experiment has been the first one conducted with gold wires in the IPEN/MB-01 reactor, being this technique implemented for use by experiments in flux mapping of the core 73 refs., 60 figs., 31 tabs.

  2. Self-organized critical behavior in pinned flux lattices

    International Nuclear Information System (INIS)

    Pla, O.; Nori, F.

    1991-01-01

    We study the response of pinned fluxed lattices, under small perturbations in the driving force, below and close to the pinning-depinning transition. For driving Lorentz forces below F c (the depinning force at which the whole flux lattice slides), the system has instabilities against small force increases, with a power-law distribution characteristic of self-organized criticality. Specifically, D(d)∼d -1,3 , where d is the displacement of a flux line after a very small force increase. We also study the initial stages of the motion of the lattice once the driving force overcomes the pinning forces

  3. The measurements of thermal neutron flux distribution in a paraffin

    Indian Academy of Sciences (India)

    The term `thermal flux' implies a Maxwellian distribution of velocity and energy corresponding to the most probable velocity of 2200 ms-1 at 293.4 K. In order to measure the thermal neutron flux density, the foil activation method was used. Thermal neutron flux determination in paraffin phantom by counting the emitted rays of ...

  4. Transport of Internetwork Magnetic Flux Elements in the Solar Photosphere

    Science.gov (United States)

    Agrawal, Piyush; Rast, Mark P.; Gošić, Milan; Bellot Rubio, Luis R.; Rempel, Matthias

    2018-02-01

    The motions of small-scale magnetic flux elements in the solar photosphere can provide some measure of the Lagrangian properties of the convective flow. Measurements of these motions have been critical in estimating the turbulent diffusion coefficient in flux-transport dynamo models and in determining the Alfvén wave excitation spectrum for coronal heating models. We examine the motions of internetwork flux elements in Hinode/Narrowband Filter Imager magnetograms and study the scaling of their mean squared displacement and the shape of their displacement probability distribution as a function of time. We find that the mean squared displacement scales super-diffusively with a slope of about 1.48. Super-diffusive scaling has been observed in other studies for temporal increments as small as 5 s, increments over which ballistic scaling would be expected. Using high-cadence MURaM simulations, we show that the observed super-diffusive scaling at short increments is a consequence of random changes in barycenter positions due to flux evolution. We also find that for long temporal increments, beyond granular lifetimes, the observed displacement distribution deviates from that expected for a diffusive process, evolving from Rayleigh to Gaussian. This change in distribution can be modeled analytically by accounting for supergranular advection along with granular motions. These results complicate the interpretation of magnetic element motions as strictly advective or diffusive on short and long timescales and suggest that measurements of magnetic element motions must be used with caution in turbulent diffusion or wave excitation models. We propose that passive tracer motions in measured photospheric flows may yield more robust transport statistics.

  5. Gamma-stability and vortex motion in type II superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Kurzke, Matthias; Spirn, Daniel

    2009-07-15

    We consider a time-dependent Ginzburg-Landau equation for superconductors with a strictly complex relaxation parameter, and derive motion laws for the vortices in the case of a finite number of vortices in a bounded magnetic field. The motion laws correspond to the flux-flow Hall effect. As our main tool, we develop a quantitative {gamma}-stability result relating the Ginzburg-Landau energy to the renormalized energy. (orig.)

  6. Gamma-stability and vortex motion in type II superconductors

    International Nuclear Information System (INIS)

    Kurzke, Matthias; Spirn, Daniel

    2009-01-01

    We consider a time-dependent Ginzburg-Landau equation for superconductors with a strictly complex relaxation parameter, and derive motion laws for the vortices in the c